Timepiece having thermoelectric generator unit

Information

  • Patent Grant
  • 6407965
  • Patent Number
    6,407,965
  • Date Filed
    Monday, June 26, 2000
    24 years ago
  • Date Issued
    Tuesday, June 18, 2002
    22 years ago
Abstract
A timepiece has a case back made of a thermally conductive material, an upper case body made of a thermally conductive material and disposed opposite to the case back, and a lower case body made of a thermally insulating material and disposed between the upper case body and the case back. A thermoelectric generator unit generates an electromotive force in accordance with heat conducted from the case back. At least one step-up circuit steps up an electromotive force generated by the thermoelectric generator unit. A storage member stores power and an electromotive force stepped up by the step-up circuit. A timepiece driving circuit is driven by power stored in the storage member or by electromotive force stepped up by the step-up circuit. A power supply operating control circuit controls power flow from the step-up circuit to the storage member and controls whether the electromotive force stepped up by the step-up circuit or the power stored in the storage member is supplied to the timepiece driving circuit. A display member displays time information in accordance with a signal outputted from the timepiece driving circuit.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a timepiece having a thermoelectric generator unit containing electrothermic elements for generating electromotive force based on the Seebeck effect. Particularly, the invention relates to a timepiece constituted to store electromotive force generated by a thermoelectric generator unit containing one or more of electrothermic elements, operate by the electromotive force and operate with a storage member as a power supply and including a flat thermal conductive body.




Further, the invention relates to a portable electronic device constituted to store electromotive force generated by a thermoelectric generator unit containing one or more of electrothermic elements in a storage member, operate by the electromotive force and operate with a storage member as a power supply and including a flat thermal conductive body.




A portable electronic device according to the invention incorporates an analog type electronic timepiece, a digital type electronic timepiece, an analog/digital composite type electronic timepiece, a timer device, an alarm device, an analog type electronic timepiece having a timer and/or an alarm, a digital type electronic timepiece having a timer and/or an alarm or an analog/digital composite type electronic timepiece having a timer and/or an alarm.




BACKGROUND ART




According to a conventional electrothermic wrist watch, as disclosed in, for example, JP-A-55-20483, a thermoelectric type generator comprising a number of individual element parts is arranged between a bottom portion of a casing made of metal and a support ring. According to the thermoelectric type generator (Peltier battery), a hot pole is placed opposedly to the bottom portion of the casing and a cold pole is placed opposed to a cover made of metal. Further, according to other structure, a thermoelectric type generator is held by an intermediary ring via a shock absorber.




According to other electronic timepiece, as disclosed in JP-A-8-43555, a 1st insulating member constitutes a heat absorbing side, a 2nd insulating member constitutes a heat radiating side, electromotive force is provided at an output end portion, the electromotive force is stored in a storage member and time display means is operated by the storage member.




Further, according to a timepiece having conventional power generating elements, as disclosed in JP-A-9-15353, four of electrothermic elements are arranged dividedly at other than a portion occupied by a movement in a space at inside of a wrist watch. According to the electrothermic element, p type, electrothermic members and n type electrothermic members are connected at end portions and form thermocouples. The electrothermic element is constituted by connecting in series all of the thermocouples.




Further, according to a conventional thermoelectric power generating wrist watch, as disclosed in JP-A-7-32590U, a thermoelectric power generating element is arranged between a case back and a module cover. The thermoelectric power generating element includes a number of thermocouples.




None of the conventional literatures discloses a timepiece having a thermoelectric generator unit containing one or more of electrothermic elements.




In an electrothermic element, a force resisting against external fore is weak. Particularly, in an electrothermic element, numbers of p type electrothermic members and n type electrothermic members each in a slender columnar shape are arranged and accordingly, when the p type electrothermic members and the n type electrothermic members are exerted with a force in a direction orthogonal to a longitudinal direction of these, there is a concern of destructing the electrothermic element. Further, also in the case in which the p type electrothermic members and the n type electrothermic members are exerted with a force along the longitudinal direction of these, when the force exceeds a constant magnitude, there is a concern of destructing the electrothermic element.




Conventionally, an electrothermic element is arranged directly in a space at inside of a wrist watch without mounting the electrothermic element as a thermoelectric generator unit and therefore, the strength of the electrothermic element cannot be increased. Further, when a plurality of the electrothermic elements are used, there is needed means for connecting the electrothermic elements.




Further, conventionally, a thermal conductive body provided for transferring heat from a thermoelectric generator unit is provided with a bent portion. Therefore, a transfer path of heat is prolonged and power generating efficiency of the thermoelectric generator unit may be deteriorated.




It is an object of the present invention to provide a timepiece having a thermoelectric generator unit and in which the power generating efficiency of the thermoelectric generator unit is improved by shortening the heat transferring path.




SUMMARY OF THE INVENTION




In order to resolve the above-described problem, a timepiece according to the invention is provided with a chargeable storage member constituting a power supply for operating the timepiece. A timepiece driving circuit for driving the timepiece is constituted to be able to operate by the storage member. Display members such as hands or the like display information in respect of time based on a signal in respect of a time output from the timepiece driving circuit.




The timepiece according to the invention is provided with an upper case body made of a thermally conductive material and a case back made of a thermally conductive material.




A thermoelectric generator unit contains one or more of electrothermic elements for generating electromotive force based on the Seebeck effect, includes a 1st thermally conductive plate constituting a heat absorbing plate and includes a 2nd thermally conductive plate constituting a heat radiating plate. A flat thermal conductive body is made of a thermally conductive material and is arranged to be brought into contact with the second thermally conductive plate. The upper case body is made of a thermally conductive material and is provided with a projected portion projected in a direction in which the case back is disposed. The projected portion is arranged to be capable of conducting heat to the thermal conductive body.




A power supply operation control circuit is installed to store the electromotive force generated by the thermoelectric generator unit in the storage member. A thermal conductive spacer is made of a thermally conductive material. The thermal conductive spacer is arranged to be brought into contact with the 1st thermally conductive plate of the thermoelectric generator unit and an inner side face of the case back. A heat insulating member having a heat insulating function is installed and by the heat insulating member, it is constituted that the case back and the upper case body are thermally insulated from each other.




Further, according to the invention, there is constituted a portable electronic device having a thermoelectric generator unit, the device comprising a thermoelectric generator unit including a 1st thermally conductive plate constituting a heat absorbing plate, electrothermic elements generating an electromotive force by the Seebeck effect and a 2nd thermally conductive plate constituting a heat radiating plate, a case back made of a thermally conductive material, a thermal conductive spacer made of a thermally conductive material and arranged to be capable of conducting heat between the thermal conductive spacer and the case back and the 1st thermally conductive plate, a flat thermal conductive body made of a thermally conductive material and arranged to be capable of conducting heat between the thermal conductive body and the 2nd thermally conductive plate, an upper case body made of a thermally conductive material and having a projected portion projected in a direction in which the case back is disposed and arranged to be capable of conducting heat between the projected portion and the thermal conductive body, a storage member constituting a power supply of the portable electronic device for storing an electromotive force generated by the thermoelectric generator unit, and a display member operated by the storage member or the electromotive force generated by the thermoelectric generator unit for displaying information related to time or a period of time.




Further, according to the invention, in a portable electronic device having a thermoelectric generator unit, the thermoelectric generator unit is constituted to include a 1st thermally conductive plate constituting a heat absorbing plate, electrothermic elements for generating electromotive force by the Seebeck effect and a 2nd thermally conductive plate constituting a heat radiating plate. The portable electronic device is installed with an exterior case for containing constituent parts of a device including the thermoelectric generator unit. The exterior case includes a heat absorbing member made of a thermally conductive material, for example, a case back and a heat radiating member made of a thermally conductive material, for example, an upper case body.




Further, the portable electronic device includes a flat thermal conductive body made of a thermally conductive material and arranged to be capable of conducting heat to the second thermally conductive plate. Further, a heat radiating member is provided with a projected portion projected in a direction in which the absorbing member is disposed and the projected portion is arranged to be capable of conducting heat to the thermal conductive body.




According to the portable electronic device, the thermal conductive spacer made of a thermally conductive and elastically deformable material, is arranged to be capable of conducting heat to the absorbing member and the 1st thermally conductive plate, and the 2nd thermally conductive plate is constituted to be capable of conducting heat to the radiating member.




Further, according to the portable electronic device, a thermal conductive spacer made of a thermally conductive and elastically deformable material, for example, silicone rubber sheet is arranged to be capable of conducting heat between the thermal conductive member and the heat absorbing member and the 1st thermally conductive plate. The thermal conductive spacer is a sheet-like part capable of firmly conducting heat from the heat absorbing member to the 1st thermally conductive plate by being compressed by the heat absorbing member and the 1st thermally conductive plate.




Further, according to the portable electronic device, the 2nd thermally conductive plate is constituted to be capable of conducting heat to the heat radiating member.




When such a portable electronic device is worn by the arm, heat of the arm is transferred to a heat absorbing member such as the case back. Heat transferred to the case back is transferred to the 1st thermally conductive plate of the thermoelectric generator unit via the thermal conductive spacer. By the heat, the electrothermic elements of the thermoelectric generator unit generate electromotive force by the Seebeck effect. Further, heat radiated from the 2nd thermally conductive plate of the thermoelectric generator unit is transferred to a projected portion of a heat radiating member via a thermal conductive body and is radiated to outside air by the radiating member.




By constituting the device in this way, there can be realized a portable electronic device such as timepiece having excellent power generating efficiency of the thermoelectric generator unit since a transfer path of heat is shortened.











BRIEF DESCRIPTION OF DRAWINGS





FIG. 1

is a step diagram showing steps of fabricating a thermoelectric generator unit used in an embodiment of a timepiece having a thermoelectric generator unit according to the invention.





FIG. 2

is a plane view of a 1st thermally conductive plate of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 3

is a sectional view of the 1st thermally conductive plate taken along a line


3


A—


3


A of FIG.


2


.





FIG. 4

is a plane view of a lead substrate of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 5

is a plane view showing a state in which the lead substrate is adhered to the 1st thermally conductive plate in the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 6

is a sectional view taken along a line


6


A—


6


A of

FIG. 5

showing a state in which the lead substrate is adhered to the 1st thermally conductive plate.





FIG. 7

is a side view of an outline of an electrothermic element of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 8

is a plane view of an upper electrothermic element substrate of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 9

is a plane view of a lower electrothermic element substrate of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 10

is a cross-sectional view of the electrothermic elements taken along a line


10


A—


10


A of FIG.


7


.





FIG. 11

is a plane view showing a state in which the electrothermic elements are adhered to the 1st thermally conductive plate in the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit.





FIG. 12

is a sectional view taken along a line


12


A—


12


A of

FIG. 11

showing a state in which the electrothermic elements are adhered to the 1st thermally conductive plate.





FIG. 13

is a plane view showing a state in which terminal patterns of the electrothermic elements and lead patterns of the lead substrate are conducted by wire bonding in the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 14

is a sectional view taken along a line


14


A—


14


A of

FIG. 13

showing a state in which the terminal patterns of the electrothermic elements and the lead pattern of the lead substrate are conducted by wire bonding.





FIG. 15

is a plane view of a unit frame of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 16

is a sectional view of the unit frame of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 17

is a plane view showing a state in which the unit frame is fixed to the 1st thermally conductive plate in the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 18

is a plane view of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 19

is a sectional view of the thermoelectric generator unit used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 20

is a sectional view of an embodiment of a timepiece entity of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 21

is a rear plane view of the embodiment of the timepiece entity of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side by removing the case back and a crown.





FIG. 22

is a rear plane view of a generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 23

is a rear plane view (part 1) of enlarged portions of the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 24

is a rear plane view (part 2) of enlarged portions of the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 25

is a rear plane view (part 3) of enlarged portions of the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 26

is a rear plane view (part 4) of enlarged portions of the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 27

is a partial sectional view (part 1) of a generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 28

is a partial sectional view (part 2) of a generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 29

is a plane view of a thermal conductive body included in the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 30

is a plane view of a circuit insulated plate included in the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 31

is a plane view of a generating block frame included in the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 32

is a plane view of a step-up circuit block included in the generating block used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 33

is a sectional view of enlarged portions showing an electric connection portion between a circuit block of a movement and the step-up circuit block according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 34

is a front view of a circuit lead terminal used for electric connection between the circuit block of the movement and the step-up circuit block according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 35

is a plane view of enlarged portions of a pattern of the circuit block of the movement installed for electric connection with the step-up circuit block and the circuit lead terminals arranged to be brought into contact with the pattern according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 36

is a sectional view of enlarged portions of the electric connection portion between the thermoelectric unit and the step-up circuit block according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 37

is a sectional view of enlarged portions showing a portion in which the thermal conductive body is fixed to an upper case body according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 38

is a sectional view of enlarged portions showing a case back, a thermal conductive spacer and the thermoelectric generator unit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 39

is a plane view of a thermal conductive spacer used in the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 40

is a sectional view of enlarged portions showing a portion in which the case back is fixed to the lower case body according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 41

is a plane view of the embodiment of the movement of the timepiece having the thermoelectric generator unit according to the invention viewed from the case back side.





FIG. 42

is an outline block diagram showing a drive portion and a wheel train according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 43

is an outline block diagram showing a constitution of circuits according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 44

is an outline block diagram showing a constitution of a step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 45

is a circuit diagram showing a constitution of an oscillation circuit used in the step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 46

is a circuit diagram showing a constitution of a 1st step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 47

is a circuit diagram showing a constitution of a 2nd step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 48

is a circuit diagram showing a constitution of a 3rd step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 49

is a circuit diagram showing a constitution of a 4th step-up circuit according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 50

is an outline block diagram showing the principle of thermoelectric generation according to the embodiment of the timepiece having the thermoelectric generator unit according to the invention.





FIG. 51

is a sectional view showing an embodiment of a portable electronic device having the thermoelectric generator unit according to the invention.





FIG. 52

is an outline block diagram of the embodiment of the portable electronic device having the thermoelectric generator unit according to the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




An explanation will be given of embodiments according to the invention in reference to the drawings as follows.




(1) A Structure of a Thermoelectric Generator Unit Used in Embodiments of a Timepiece Having a Thermoelectric Generator Unit According to the Invention and a Method of Fabricating Thereof




An explanation will be given of a method of fabricating a thermoelectric generator unit used in a timepiece having a thermoelectric generator unit according to the invention.




In reference to

FIG. 1

, firstly, a 1st thermally conductive plate


120


is prepared (step


101


).




In reference to FIG.


2


and

FIG. 3

, the 1st thermally conductive plate


120


is made of a metal having excellent thermal conductivity, for example, aluminum, copper or the like. When the 1st thermally conductive plate


120


is fabricated by copper, it is preferable to plate the surface with nickel.




The 1st thermally conductive plate


120


is a thin plate member having substantially a rectangular plane shape. The 1st thermally conductive plate


120


is provided with a lead substrate base portion


120




a


for attaching a lead substrate, a lead substrate supporting guide hole


120




b




1


for guiding the lead substrate in attaching the lead substrate, a manufacturing guide hole


120




b




2


and electrothermic element base portions


120




d




1


and


120




d




2


for attaching electrothermic elements.




When 10 of electrothermic elements are used, 5 of electrothermic elements are attached to the electrothermic element base portion


120




d




1


and 5 of electrothermic elements are attached to the electrothermic element base portion


120




d




2


. Accordingly, the plane shape of the electrothermic element base portions


120




d




1


and


120




d




2


is determined in compliance with the plane shape of the electrothermic element. The thickness of the electrothermic element base portions


120




d




1


and


120




d




2


is thinner than the thickness of the electrothermic element base portion


120




a.






In reference to

FIG. 4

, a lead substrate


130


is formed in a shape including a slender portion. The lead substrate


130


may be a glass epoxy substrate or may be a polyimide film substrate.




The lead substrate


130


is installed with lead patterns


130




a




1


through


130




a




9


for wiring in series 10 of electrothermic elements and 2 of output terminal patterns


130




t




1


and


130




t




2


for constituting output terminals of the thermoelectric generator unit.




The lead substrate


130


is installed with supporting guide holes


130




b




1


and


130




b




2


for positioning the lead substrate


130


in attaching the lead substrate


130


to the 1st thermally conductive plate


120


. Further, the lead substrate


130


is installed also with assembling guide holes


130




b




3


and


130




b




4


. The position of the supporting guide hole


130




b




1


is determined in correspondence with the position of the lead substrate supporting guide hole


120




b




1


of the 1st thermally conductive plate


120


.




In reference to

FIG. 1

, successively, an adhesive agent is coated on the lead substrate base portion


120




a


of the 1st thermally conductive plate


120


(step


102


). The adhesive agent is preferably an epoxy-species adhesive agent. The adhesive agent may be an adhesive agent of other kind such as a thermosensible adhesive agent or the like or may be a sheet-like adhesive agent.




In reference to FIG.


5


and

FIG. 6

, successively, the lead substrate supporting guide hole


120




b




1


of the 1st thermally conductive plate


120


and the supporting guide hole


130




b




1


of the lead substrate


130


are aligned and the lead substrate


130


is adhered to the 1st thermally conductive plate


120


by an adhesive agent


132


(step


103


).




In reference to FIG.


7


through

FIG. 9

, an electrothermic element


140


of the thermoelectric generator unit used in a timepiece having the thermoelectric generator unit according to the invention, includes an upper electrothermic element substrate


142


, a lower electrothermic element substrate


144


, a plurality of p-type semiconductors


146


and a plurality of n-type semiconductors


148


.




The upper electrothermic element substrate


142


is provided with a plurality of conducting patterns


142




a


for conducting the p-type semiconductors


146


and the n-type semiconductors


148


. The lower electrothermic element substrate


144


is provided with a plurality of conducting patterns


144




a


for conducting the p-type semiconductors


146


and the n-type semiconductors


148


and terminal patterns


144




b




1


and


144




b




2


of the electrothermic elements


140


.




In reference to FIG.


7


through

FIG. 10

, the plurality of p-type semiconductors


146


and the plurality of n-type semiconductors


148


are connected to the patterns of the upper electrothermic element substrate


142


and the patterns of the lower electrothermic element substrate


144


such that the respective p-type semiconductors


146


and the respective n-type semiconductors


148


are connected alternately in series.




According to the electrothermic element


140


constituted in this way, when, for example, a side having the upper electrothermic element substrate


142


constitutes a heat radiating side and a side having the lower electrothermic element substrate


144


constitutes a heat absorbing side, in the n-type semiconductor


148


, electrons are moved toward the upper electrothermic element substrate


142


on the heat radiating side and in the p-type semiconductor


146


, electrons are moved toward the lower electrothermic element substrate


144


on the heat absorbing side. The respective p-type semiconductors


146


and the respective n-type semiconductors


148


are electrically connected in series via the conducting patterns


142




a


of the upper electrothermic element substrate


142


and the conducting patterns


144




a


of the lower electrothermic element substrate


144


and accordingly, transfer of heat is converted into current in the p-type semiconductors


146


and the n-type semiconductors


148


and an electromotive force is generated between the terminal patterns


144




b




1


and


144




b




2


of the lower electrothermic element substrate


144


.




In reference to FIG.


1


and

FIG. 2

, successively, an adhesive agent is coated on the electrothermic element base portions


120




d




1


and


120




d




2


of the 1st thermally conductive plate


120


(step


104


). The adhesive agent used in step


104


is a thermally conductive adhesive agent of, for example, silver paste. The adhesive agent may be a thermally conductive epoxy-species adhesive agent or may be a thermally conductive adhesive agent of other kind.




In reference to

FIG. 1

, FIG.


11


and

FIG. 12

, successively, 5 of the electrothermic elements


140




a




1


through


140




a




5


are fixedly adhered to one of the electrothermic element base portion


120




d




1


of the 1st thermally conductive plate


120


and 5 of the electrothermic elements


140




a




6


through


140




a




10


are fixedly adhered to other of the electrothermic element base portion


120




d




2


(step


105


). In step


105


, in a state in which the respective terminal patterns


144




b




1


and


144




b




2


of the lower electrothermic element substrates


144


are arranged at a vicinity of the lead substrate


130


, the lower side faces of the lower electrothermic element substrates


140


of the electrothermic elements


144


are adhered to the electrothermic element base portions


120




d




1


and


120




d




2


by a silver paste


134


. Thereby, the lower electrothermic element substrates


144


of the electrothermic elements


140


and the 1st thermally conductive plate


120


are made thermally conductive to each other.




Therefore, as shown by

FIG. 11

, 5 of the electrothermic elements


140




a




1


through


140




a




5


are arranged on one side (right side of drawing) of the lead substrate


130


and 5 of the electrothermic elements


140




a




6


through


140




a




10


are arranged on other side (left side of drawing) of the lead substrate


130


.




Although according to the above-described embodiment of the thermoelectric generator unit, 10 of the electrothermic elements


140




a




1


through


140




a




10


are used, a number of the electrothermic elements


140


may be 1 or 2 or more. Further, although a number of the electrothermic elements


140


is preferably an even number, it may be an odd number.




In reference to

FIG. 1

, successively, the silver paste used in step


105


is dried (step


106


). It is preferable in step


106


that, for example, drying temperature is 120° C. through 150° C. and drying time is 2 hours through 5 hours.




Next, step inspection (


1


) is carried out (step


107


). In step inspection (


1


), resistance of each of the electrothermic elements


140


is measured.




In reference to

FIG. 1

, FIG.


13


and

FIG. 14

, successively, the respective terminal patterns


144




b




1


and


144




b




2


of 10 of the electrothermic elements


140




a




1


through


140




a




10


, lead patterns


130




a




1


through


130




a




9


and the output terminal patterns


130




t




1


and


130




t




2


of the lead substrate


130


, are conducted by wire bonding


150


(step


108


). The wire bonding


150


wires the electrothermic elements


140


such that the plurality of electrothermic elements


140


are connected in series.




In reference to

FIG. 13

, the terminal pattern


144




b




1


of the electrothermic element


140




a




1


and the output terminal pattern


130




t




1


of the lead substrate


130


are conducted by the wire bonding


150


. The terminal pattern


144




b




2


of the electrothermic element


144




a




1


and the lead pattern


130




a




1


of the lead substrate


130


are conducted by the wire bonding


150


. Similarly, the electrothermic element


140




a




1


through the electrothermic element


140




a




5


are wired in series and the electrothermic element


140




a




6


through the electrothermic element


140




a




10


are wired in series by the wire bonding


150


. The electrothermic element


140




a




5


and the electrothermic element


140




a




10


are wired in series via the lead pattern


130




a




9


of the lead substrate


130


by the wire bonding


150


.




The terminal pattern


144




b




1


of the electrothermic element


140




a




6


and the lead pattern


130




a




5


of the lead substrate


130


are conducted by the wire bonding


150


. The terminal pattern


140




b




2


of the electrothermic element


140




a




6


and the output terminal pattern


130




t




2


of the lead substrate


130


are conducted by the wire bonding


150


.




By step


108


, 10 of the electrothermic elements


140




a




1


through


140




a




10


are connected in series and the patterns


130




t




1


and


130




t




2


of the lead substrate


130


constitute the output terminals of the thermoelectric generator unit.




In reference to

FIG. 1

, successively, step inspection (


2


) is carried out (step


109


). In step inspection (


2


), resistance of the thermoelectric generator unit connected in series with 10 of the electrothermic elements


140




a




1


through


140




a




10


is measured.




In reference to FIG.


15


and

FIG. 16

, a unit frame


160


of the thermoelectric generator unit used in a timepiece having the thermoelectric generator unit according to the invention, is a member having a contour substantially in a rectangular shape and is constituted in a shape capable of surrounding 10 of the electrothermic elements


140




a




1


through


140




a




10


. The unit frame


160


is provided with a lower supporting portion


160




d


for attaching the 1st thermally conductive plate


120


, an upper supporting portion


160




e


for attaching a 2nd thermally conductive plate and a lead substrate escaping portion


160




f


for escaping the lead substrate


130


.




A distance between the lower supporting portion


160




d


and the upper supporting portion


160




e


of the unit frame


160


is constituted to produce a gap between a lower face of the 2nd thermally conductive plate


170


and an upper face of the upper electrothermic element substrate


142


of the electrothermic element


140


when the 1st thermally conductive plate


120


and the 2nd thermally conductive plate


170


are attached to the unit frame


160


.




The unit frame


160


is preferably fabricated by plastic such as ABS resin, polycarbonate or acrylic resin.




In reference to FIG.


1


and

FIG. 17

, successively, the unit frame


160


is fixed to the 1st thermally conductive plate


120


such that the unit frame


160


surrounds 10 of the electrothermic elements


140




a




1


through


140




a




10


(step


110


). At this occasion, the lead substrate escaping portion


160




f


of the unit frame


160


is arranged to escape the upper face of the lead substrate


130


.




Fixing of the unit frame


160


to the 1st thermally conductive plate


120


may be carried out by fitting, adhering or melting a portion of the unit frame


160


to adhere to the 1st thermally conductive plate


120


.




In reference to

FIG. 1

, successively, grease is adhered to the upper faces of the upper electrothermic element substrates


142


of 10 of the electrothermic elements


140




a




1


through


140




a




10


(step


111


).




It is preferable that grease used in step


111


is silicone grease having excellent thermal conductivity and, for example, commercial name “Toshiba silicone pound” is used.




In reference to FIG.


18


and

FIG. 19

, successively, the 2nd thermally conductive plate


170


is fixed to the upper supporting portion


160




e


of the unit frame


160


(step


112


). At this occasion, there is a gap between the lower face of the 2nd thermally conductive plate


170


and the upper face of the upper electrothermic element substrate


142


of the electrothermic element


140


and silicone grease


172


is arranged in the gap. Therefore, the 2nd thermally conductive plate


170


and the upper electrothermic element substrate


142


are made thermally conductible to each other by the silicone grease


172


.




The 2nd thermally conductive plate


170


is made of a metal having excellent thermal conductivity, for example, aluminum, copper or the like. When the 2nd thermally conductive plate


170


is made of copper, it is preferable to plate the surface with nickel. The 2nd thermally conductive plate


170


is a thin plate member having a substantially rectangular plane shape. The outer shape of the 2nd thermally conductive plate


170


is formed in dimensions and a shape capable of attaching to the upper supporting portion


160




e


of the unit frame


160


.




Fixing of the 2nd thermally conductive plate


170


to the unit frame


160


may be carried out by fitting, adhering or melting a portion of the unit frame


160


to adhere to the 2nd thermally conductive plate


170


.




By attaching the 2nd thermally conductive plate


170


to the unit frame


160


, 10 of the electrothermic elements


140




a




1


through


140




a




10


contained in the thermoelectric generator unit


180


can firmly be protected.




Guide pins


170




c


and


170




d


which are used for attaching the thermoelectric generator unit


180


to other member are installed on one face of the 2nd thermally conductive plate


170


. The 2nd thermally conductive plate


170


is attached to the unit frame


160


in a state in which the guide pins


170




c


and


170




d


are directed to outside. Although a number of the guide pins is preferably 2, it may be 1 or 3 or more.




In reference to

FIG. 1

, successively, step inspection (


3


) is carried out (step


113


). In step inspection (


3


), resistance of the thermoelectric generator unit


180


is measured.




Next, step inspection (


4


) is carried out (step


114


). In step inspection (


4


), the power generating function of the thermoelectric generator unit is measured. Measurement of the power generating function is carried out by heating one thermally conductive plate of the thermoelectric generator unit by a heater and measuring voltage output from the thermoelectric generator unit


180


by a voltmeter. When the measurement is carried out, a difference between temperature in a chamber where the thermoelectric generator unit


180


is arranged and heating temperature of the heater is maintained constant.




Any of the step inspections may be omitted or additional step inspection may be carried out as necessary.




There is shown as follows an example of sizes of the thermoelectric generator unit


180


used in a timepiece having the thermoelectric generator unit according to the invention and constituent parts used in the thermoelectric generator unit.




Length of thermoelectric generator unit in a longitudinal direction: 15.2 mm




Width of thermoelectric generator unit in a lateral direction: 10.0 mm




Thickness of thermoelectric generator unit: 2.7 mm




Length of electrothermic element in the longitudinal direction: 2.4 mm




Width of electrothermic element in the lateral direction: 2.2 mm




Thickness of electrothermic element: 1.3 mm




Maximum thickness of 1st thermally conductive plate: 0.5 mm




Thickness of 2nd thermally conductive plate: 0.5 mm




Distance between outer side face and inner face of unit frame: 0.8 mm




When voltage is generated by using the thermoelectric generator unit


180


, the 1st thermally conductive plate


120


may constitute a heat absorbing plate and the 2nd thermally conductive plate


170


may constitute a heat radiating plate, or the 1st thermally conductive plate


120


may constitute a heat radiating plate and the 2nd thermally conductive plate


170


may constitute a heat absorbing plate. By way of determining the heat absorbing plate and the heat radiating plate, the polarity of voltage generated between the patterns


130




t




1


and


130




t




2


of the lead substrate


130


is changed.




Further, the thermoelectric generator unit used in a timepiece according to the invention may be fabricated by steps shown below.




The 1st thermally conductive plate is prepared, an epoxy-species adhesive agent is coated on the lead substrate base portion


120




a


of the 1st thermally conductive plate


120


, the lead substrate


130


is adhered to the 1st thermally conductive plate


120


and the unit frame


160


is fixed to the 1st thermally conductive plate


120


.




Next, a thermally conductive adhesive agent such as silver paste is coasted on the electrothermic element base portions


120




d




1


through


120




d




10


of the 1st thermally conductive plate


120


and 10 of the electrothermic elements


140




a




1


through


140




a




10


are respectively adhered fixedly to the electrothermic element base portions


120




d




1


and


120




d




2


of the 1st thermally conductive plate


120


. Next, silver paste used in step


105


mentioned above is dried and resistance of each of the electrothermic elements


140


is measured.




Next, the respective terminal patterns


144




b




1


and


144




b




2


of 10 of the electrothermic elements


140




a




1


through


140




a




10


and the lead patterns


130




a




1


through


130




a




9


and the output terminal patterns


130




t




1


and


130




t




2


of the lead substrate


130


are conducted by the wire bonding


150


. The wire bonding


150


wires the electrothermic elements


140


such that the plurality of electrothermic elements


140


are connected in series.




Next, resistance of the thermoelectric generator unit connected in series with 10 of the electrothermic elements


140




a




1


through


140




a




10


is measured.




Next, silicone grease is attached to the upper face of the upper electrothermic element substrates of 10 of the electrothermic elements


140




a




1


through


140




a




10


.




Next, the 2nd thermally conductive plate


170


is fixed to the upper supporting portion


160




e


of the unit frame


160


. The 2nd thermally conductive plate


170


and the upper electrothermic element substrate


142


are made thermally conductible by the silicone grease


172


.




Next, resistance of the thermoelectric generator unit


180


is measured and the power generating function of the thermoelectric generator unit is measured.




(2) A Structure of an Embodiment of a Case of a Timepiece Having a Thermoelectric Generator Unit According to the Invention




Next, an explanation will be given of a structure of a timepiece having a thermoelectric generator unit according to the invention.




In reference to FIG.


20


and

FIG. 21

, a complete entity of a timepiece having the thermoelectric generator unit according to the invention, that is, a timepiece


200


is provided with a case


202


, a movement


204


, a generating block


206


, a dial


208


, hands


210


, a casing frame


212


and a crown


214


.




The case


202


includes an upper case body


220


, a decorative bezel


222


, a lower case body


224


, a case back


226


and glass


228


. The upper case body


220


is fabricated by a thermally conductive material. It is preferable to fabricate the upper case body


220


by brass, stainless steel or the like. It is preferable to fabricate the decorative bezel


222


by brass or stainless steel. Although the decorative bezel


222


is attached to the upper case body


220


, the decorative bezel


222


may not be provided. The lower case body is constituted by a material having excellent heat insulating performance. That is, the lower case body


224


is constituted by a thermally insulating member for thermally insulating the upper case body


220


from the case back


226


. It is preferable to fabricate the lower case body


224


by plastic of U polymer, ABS resin or the like.




The case back


226


is fabricated by a thermally conductive material. It is preferable to fabricate the case back


226


by a metal of stainless steel or the like. The casing frame


212


is fabricated by, for example, plastic. The glass


228


is attached to the upper case body


220


.




“Movement” signifies a mechanical entity including portions for driving a timepiece. The movement


204


is installed with a power supply, a timepiece driving circuit operated by the power source for driving a timepiece, a converter of a step motor or the like operated by a signal output from the timepiece driving circuit, a wheel train rotated based on the operation of the converter and a switch mechanism for modifying positions of the hands


210


. The hands


210


are attached to the wheel train and display a information in respect of time or a period of time by rotation of the wheel train. The hands


210


include, for example, a hour hand, a minute hand and a second hand.




In respect of the “movement”, a side thereof having a case back


226


is referred to as “case back side” of the “movement” and a side thereof having the glass


228


is referred to as “glass side” of the “movement”.




The dial


208


is disposed on the “glass side” of the movement


204


. The casing frame


212


is attached from the “case back side” of the movement


204


.




(3) Structure of a Generating Block Having the Thermoelectric Generator Unit Used in an Embodiment of a Timepiece Having the Thermoelectric Generator Unit According to the Invention




In reference to FIG.


22


through

FIG. 28

, the generating block


206


including the thermoelectric generator unit used in a timepiece having the thermoelectric generator unit according to the invention, is installed with the thermoelectric generator unit


180


, a step-up circuit block


240


, a circuit insulated plate


242


, a thermal conductive body


244


and a generator block frame


246


.




In reference to

FIG. 29

, the thermal conductive body


244


is a plate-like member having a substantially circular outer peripheral shape and is fabricated by a thermally conductive material. It is preferable to fabricate the thermal conductive body


244


by a metal of copper, brass or the like. It is preferable to fabricate the thermal conductive body


244


in a flat shape which is not subjected to a bending process. By the constitution, the thermal conductive body


244


can be fabricated by simple fabrication steps.




In reference to

FIG. 30

, the circuit insulated plate


242


is a thin plate member having a substantially circular outer peripheral shape and is fabricated by an electrically insulating material. It is preferable to fabricate the circuit insulated plate


242


by plastic of polyimide, polyester or the like.




In reference to

FIG. 31

, the generating block frame


246


is a member having a substantially circular outer peripheral shape and is fabricated by an electrically insulating material. It is preferable to fabricate the generating block frame


246


by plastic of polycarbonate, polyacetal or the like. 3 of screw pins


246




a


through


246




c


are fixed to the generating block frame


246


.




In reference to

FIG. 32

, the step-up circuit block


240


is installed with a step-up circuit substrate


250


having a substantially circular outer peripheral shape. The step-up circuit substrate


250


is constituted by a glass epoxy substrate or a polyimide substrate. The step-up circuit substrate


250


is attached with a step-up integrated circuit


252


for constituting the step-up circuit, a plurality of capacitors


260


, a tantalum capacitor


262


and a plurality of diodes


264


. A detailed explanation will be given later of the constitution of the step-up circuit.




In reference to FIG.


22


through

FIG. 28

again, in fabricating the generating block


206


, in a state in which the guide pins


170




c


and


170




d


are inserted into the thermal conductive body


244


and an outer side face of the 2nd thermally conductive plate


170


is brought into contact with the thermal conductive body


244


, the thermoelectric generator unit


180


is attached to the thermal conductive body


244


. By a thermoelectric generator unit lead terminal support screw


290


, the output terminal patterns


130




t




1


and


130




t




2


of the lead substrate


130


of the thermoelectric generator unit are brought into contact with a pattern of the step-up circuit substrate


250


to thereby fix the lead substrate


130


to the generating block frame


246


. Under the state, the step-up circuit substrate


250


, the circuit insulated plate


242


and the thermal conductive body


244


are interposed between the lead substrate


130


and the generating block frame


246


. As a result, the output terminal patterns


130




t




1


and


130




t




2


of the lead substrate


130


are conducted to the pattern of the step-up circuit substrate


250


. Further, by 2 of thermal conductive body support screws


292


, the thermal conductive body


244


is fixed to the generating block frame


246


.




(4) A Structure of an Embodiment of a Timepiece Having the Thermoelectric Generator Unit According to the Invention




In reference to

FIG. 20

, the movement


204


attached with the dial


208


and the hands


210


is integrated to the upper case body


220


and the casing frame


212


is integrated to the case back side of the movement


204


. The generating block


206


is arranged on the case back side of the movement


204


and is fixed to the upper case body


220


by a generating block support screw


310


.




A thermal conductive spacer


320


is arranged on the case back side of the thermoelectric generator unit


180


. The case back


226


is fixed to the lower case body


224


. Under the state, the thermal conductive spacer


320


is arranged such that one face thereof is brought into contact with the 1st thermally conductive plate


120


of the thermoelectric generator unit


180


and other face thereof is brought into contact with an inner side face of the case back


226


.




In reference to

FIG. 33

, according to an embodiment of a timepiece having the thermoelectric generator unit of the invention, the movement


204


includes a circuit block


350


attached with an integrated circuit for driving the timepiece for controlling operation of the timepiece. A portion of a face of the circuit block


350


on the case back side is arranged to be opposed to a portion of a face of the generating block frame


246


on the glass side.




In reference to

FIG. 34

, a step-up circuit lead terminal


216


is fabricated by an elastic material of spring steel or the like and is provided with a shape of a helical spring.




In reference to

FIG. 33

again, one end of the step-up circuit lead terminal


216


is brought into contact with the pattern of the step-up circuit substrate


250


and other end thereof is brought into contact with the pattern of the circuit block


350


. The step-up circuit lead terminal


216


conducts the pattern of the step-up circuit substrate


250


with the pattern of the circuit block


350


in a compressed state.




In reference to

FIG. 35

, according to an embodiment of a timepiece having the thermoelectric generator unit of the invention, 8 of the step-up circuit lead terminals


216


are installed and the respectives conduct patterns of 8 of the step-up circuit substrates with patterns of 8 of the circuit blocks


350


. According to the step-up circuit lead terminals


216


, two of them are installed for transmitting clock signals for step-up circuits, one of them is installed for transmitting a charge switch signal, one of them is installed for transmitting a generation detecting signal, two of them are installed for transmitting a secondary battery voltage detecting signal, one of them is installed for a plus electrode and one of them is installed for GND (ground).




In reference to

FIG. 36

, under a state in which the step-up circuit substrate


250


of the step-up circuit block


240


, the circuit insulated plate


242


and the thermal conductive body


244


are interposed between the lead substrate


130


and the generating block frame


246


, the lead substrate


130


is fixed to the generating block frame


246


. The lead substrate


130


is fixed to the generating block frame


246


by arranging a lead substrate holding plate


291


on the lead substrate


130


and fastening the thermoelectric generator unit lead terminal support screw


290


to a screw pin


246




a


installed in the generating block frame


246


.




In reference to

FIG. 37

, the upper case body


220


is provided with projected portions


220




a


projected in a direction of the case back. The projected portions


220




a


are formed in a ring-like shape substantially along a circumference. That is, the projected portions


220




a


are arranged on the outer side of the movement substantially along the outer periphery of the movement of the timepiece.




A face of the thermal conductive body


244


on the glass side is brought into contact with the projected portions


220




a


of the upper case body


220


. The thermal conductive body


244


is a flat member and needs not to bend in fabricating the thermal conductive body


244


. The thermal conductive body


244


is fixed to the upper case body


220


by screwing to fasten the thermal conductive body support screws


292


to female screws installed in the upper case body


220


. The thermal conductive body


244


is brought into contact with the upper case body


220


and accordingly, heat transferred from the thermoelectric generator unit


180


is transferred to the projected portions


220




a


of the upper case body


220


via the thermal conductive body


244


.




According to the thermal conductive body


244


used in the timepiece of the invention, the surface area is smaller than that of a conventional thermal conductive body in which bending is carried out. As a result, by using the thermal conductive body


244


, heat can be transferred extremely efficiently from the 2nd thermally conductive plate


170


to the projected portions


220




a


of the upper case body


220


.




In reference to

FIG. 38

, according to the thermal conductive spacer


320


, one face thereof is brought into contact with the 1st thermally conductive plate


120


of the thermoelectric generator unit


180


and other face thereof is brought into contact with the inner side face of the case back


226


.




In reference to

FIG. 39

, the thermal conductive spacer


320


is constituted in a shape in which portions of a circular shape are cut to remove. The shape of the thermal conductive spacer


320


is determined to correspond to the shape of the 1st thermally conductive plate


120


. The thermal conductive spacer


320


is fabricated by a thermally conductive material. It is preferable to fabricate the thermal conductive spacer


320


by a silicone rubber sheet.




Such a silicone rubber sheet can be obtained as, for example, “Heat radiating silicone rubber sheet TC-TH type” by Shinetsu Chemicals Co., Ltd., or “Gap pad” and “Soft pad” of Kitagawa Kogyo Co., Ltd. Such a silicone rubber sheet is soft, compressible and thermally conductive.




In reference to

FIG. 38

, when the thermoelectric generator unit


180


is attached to the timepiece, a gap T


3


between a face


180




f


of the thermoelectric generator unit


180


on the case back side and an inner side face


226




f


of the case back


226


does not become a constant value owing to dispersions in dimensions of related parts. That is, the thickness of the upper case body


220


, the thickness of the thermal conductive body


244


, the thickness of the thermoelectric generator unit


180


, the position of the inner side face


226




f


of the case back


226


and the thickness of the lower case body


224


are respectively provided with tolerances (dispersions in product dimensions) and accordingly, the gap T


3


between the face


180




f


of the thermoelectric generator unit


180


on the case back side and the inner side face


226




f


of the case back


226


is also dispersed. Accordingly, the case back


226


cannot be fixed to the lower case body


224


such that the face


180




f


of the thermoelectric generator unit


180


on the case back side and the inner side face


226




f


of the case back


226


are brought into direct contact with each other. However, the thermal conductive spacer


320


is compressible and accordingly, when the thermal conductive spacer


320


is arranged between the face


180




f


of the thermoelectric generator unit


180


on the case back side and the inner side face


226




f


of the case back


226


, by compressing the thermal conductive spacer


320


, the 1st thermally conductive plate


120


of the thermoelectric generator unit


180


and the case back


226


can be brought into a thermally conductive state.




According to the invention, the thickness of the thermal conductive spacer


320


is constituted to be larger than a maximum value of the gap between the face


180




f


of the thermoelectric generator unit


180


on the case back side and the inner side face


226




f


of the case back


226


in consideration of tolerances of related parts. For example, when the thickness of the thermal conductive spacer


320


is set to 0.5 mm, the thermal conductive spacer


320


is integrated to the timepiece and the case back


226


is fixed to the lower case body


224


, tolerances of relates parts can be determined such that the thickness of the thermal conductive spacer


320


becomes 0.1 mm through 0.4 mm. By such a constitution, heat can efficiently be transferred always from the case back


226


to the 1st thermally conductive plate


120


of the thermoelectric generator unit


180


via the thermal conductive spacer


320


.




In reference to

FIG. 40

, by fastening to screw a case back support screw


372


to a female screw installed in the lower case body


224


, the case back


226


is fixed to the lower case body


224


. It is preferable to provide the case back support screws


372


by a plural number, for example, four. A packing


374


is arranged between the upper case body


220


and the lower case body


224


and a packing


376


is arranged between the case back


226


and the lower case body


224


.




In reference to FIG.


41


and

FIG. 42

, power supply of the timepiece, that is, a secondary battery.


600


is arranged in the movement


204


. The secondary battery


600


constitutes a storage member


420


for storing electromotive force generated by the thermoelectric generator unit


180


. It is preferable to constitute the secondary battery


600


by a chargeable battery such as an ion lithium secondary battery. Such a chargeable battery can be obtained as “Titanium lithium ion secondary battery MT920” (diameter 9.5 mm×thickness 2.0 mm, nominal capacity; 3.0 mAh, nominal voltage; 1.5 vol.) made by Matsushita Denchi Co., Ltd. As a modified example, in place of the secondary battery


600


, a chargeable capacitor can also be utilized.




The movement


204


is installed with the circuit block


350


. A timepiece driving integrated circuit


630


for controlling operation of the timepiece is attached to the circuit block


350


. The timepiece driving integrated circuit


630


includes a timepiece driving circuit


418


. A crystal oscillator


602


constituting an oscillation source is attached to the circuit block


350


. The timepiece driving integrated circuit


630


includes a timepiece driving oscillation circuit, a timepiece driving dividing circuit and a motor driving circuit.




The movement


204


is installed with a switch mechanism including a winding stem


632


, a setting lever (not illustrated), a yoke (not illustrated) and a worm wheel pair (not illustrated), a switcher including a coil block


610


, a stator


612


and a rotor


614


and a wheel train including a fifth wheel & pinion


616


, a fourth wheel & pinion


618


, a third wheel & pinion


620


, a center wheel & pinion


622


, a minute wheel


624


and an hour wheel


626


. A second hand


640


is attached to the fourth wheel and pinion


618


. A minute hand


642


is attached to the center wheel & pinion


622


. An hour hand


646


is attached to the hour wheel


626


. The second hand


640


, the minute hand


642


and the hour hand


646


constitute the hands


210


.




In reference to

FIG. 20

, the crown


214


is attached to the winding stem


632


.




(5) A Construction of a Step-up Circuit Used in an Embodiment of a Timepiece Having the Thermoelectric Generator Unit According to the Invention




In reference to

FIG. 43

, a step-up circuit


410


is installed for stepping up voltage generated by the thermoelectric generator unit


180


. An oscillation circuit


412


is installed for driving the step-up circuit


410


. A Schottky diode


414


is installed for rectifying voltage generated by the thermoelectric generator unit


180


and voltage stepped up by the step-up circuit


410


. A power supply operation control circuit


416


is installed for controlling flow of power from the step-up circuit


410


to a timepiece driving circuit


418


, flow of power from the step-up circuit


410


to the storage member


420


and flow of power from the storage member


420


to the timepiece driving circuit


418


, corresponding to the value of voltage stepped up by the step-up circuit


410


. The storage member


420


is installed for storing power stepped up by the step-up circuit


410


and supplying power to the timepiece driving circuit


418


. The timepiece driving circuit


418


is constituted to operate by power stepped up by the step-up circuit


410


or power stored in the storage member


420


.




An output terminal of the thermoelectric generator unit


180


is connected to a terminal for inputting start voltage of the step-up circuit


410


. A p-type electrode of the Schottky diode


414


is connected to the output terminal of the thermoelectric generator unit


180


. An n-type electrode of the Schottky diode


414


is connected to a terminal for oscillation circuit power supply of the oscillation circuit


412


. A terminal for step-up voltage output of the step-up circuit


410


is connected to an input terminal of the power supply operation control circuit


416


. A storage terminal of the power supply operation control circuit


416


is connected to an input terminal of the storage member


420


. An output terminal of the power supply operation control circuit


416


is connected to a power supply terminal of the timepiece driving circuit


418


.




Voltage at the output terminal of the thermoelectric generator unit


180


is designated by notation Vp. Voltage of the step-up voltage output terminal of the step-up circuit


410


is designated by notation Vpp. Voltage of the power supply terminal of the timepiece driving circuit


418


is designated by notation Vic. Voltage of the input terminal of the storage member


420


is designated by notation Vca.




In reference to

FIG. 44

, FIG.


46


and

FIG. 47

, according to an embodiment of a timepiece having the thermoelectric generator unit of the invention, the step-up circuit


410


is constituted by a step-up circuit of “Switched capacitor system”. The step-up circuit


410


includes a 1st step-up circuit


430


, a 2nd step-up circuit


432


, a 3rd step-up circuit


434


, a 4th step-up circuit


436


, an inverter circuit


438


and smoothing capacitors


440


,


442


and


444


.




A start voltage input terminal


450


of the step-up circuit


410


is connected to an input terminal of the 1st step-up circuit


430


. An output terminal of the 1st step-up circuit


430


is connected to an input terminal of the 2nd step-up circuit


432


and also connected to one electrode of the smoothing capacitor


440


. Other electrode of the smoothing capacitor


440


is connected to a GND terminal. An output terminal of the 2nd step-up circuit


432


is connected to an input terminal of the 3rd step-up circuit


434


and also connected to one electrode of the smoothing capacitor


442


. Other electrode of the smoothing capacitor


442


is connected to a GND terminal. An output terminal of the 3rd step-up circuit


434


is connected to an input terminal of the 4th step-up circuit


436


and also connected to one electrode of the smoothing capacitor


444


. Other electrode of the smoothing capacitor


444


is connected to a GND terminal. An output terminal of the 4th step-up circuit


436


constitutes a step-up voltage output terminal


452


of the step-up circuit


410


.




A pulse signal input terminal


454


for inputting a pulse signal from the oscillation circuit


412


is connected to an input terminal of the inverter circuit


438


and also connected, to a 1st pulse signal input terminal


494


of the 1st step-up circuit


430


, a 1st pulse signal input terminal


524


of the 2nd step-up circuit


432


, a 1st pulse signal input terminal


554


of the 3rd step-up circuit


434


and a 1st pulse signal input terminal


554


of the 4th step-up circuit


436


. The output terminal of the inverter circuit


438


is connected to a 2nd pulse signal input terminal


498


of the 1st step-up circuit


430


, a 2nd pulse signal input terminal


528


of the 2nd step-up circuit


432


, a 2nd pulse signal input terminal


558


of the 3rd step-up circuit


434


and a 2nd pulse signal input terminal


558


of the 4th step-up circuit


436


.




Next, an explanation will be given of operation of the step-up circuit


410


.




The 1st step-up circuit


430


, the 2nd step-up circuit


432


, the 3rd step-up circuit


434


and the 4th step-up circuit


436


input the pulse signal from the oscillation circuit


412


. The 1st step-up circuit


430


steps up to substantially double the voltage input from the start voltage input terminal


450


. The 2nd step-up circuit


432


steps up to substantially double further voltage output from the 1st step-up circuit


430


. The 3rd step-up circuit


434


steps up to substantially double further voltage output from the 2nd step-up circuit


432


. The 4th step-up circuit


436


steps up to substantially double further voltage output from the 3rd step-up circuit


434


. Accordingly, a total of substantially 16 times of step up of voltage is carried out by the 1st step-up circuit


430


, the 2nd step-up circuit


432


, the 3rd step-up circuit


434


and the 4th step-up circuit


436


.




Next, an explanation will be given of the oscillation circuit


412


.




In reference to

FIG. 45

, an output terminal of an inverter circuit


460


is connected to an input terminal of an inverter circuit


462


and connected also to a 1st electrode of a capacitor


464


. An output terminal of the inverter circuit


462


is connected to an input terminal of an inverter circuit


466


and connected to a 1st electrode of a capacitor


468


. An output terminal of the inverter circuit


466


is connected to an input terminal of the inverter circuit


460


, an input terminal of an inverter circuit


470


and a 1st electrode of a capacitor


472


. An output terminal of the inverter circuit


470


is connected to an input terminal of an inverter circuit


474


. An output terminal of the inverter circuit


474


is connected to a pulse signal output terminal


476


. A pulse signal P


1


is constituted to be output from the pulse signal output terminal


476


. 2nd electrodes of the capacitors


464


,


468


and


472


are connected to a GND terminal


478


constituting a low potential electrode of the storage member


420


.




Power supply terminals of the respective inverter circuits are connected to a power supply terminal


480


of the oscillation circuit


412


. Ground terminals of the respective inverter circuits are connected to the GND terminal


478


. By the constitution of the circuits, a pulse signal having duty of about 50 & can be obtained.




In the oscillation circuit


412


, when the threshold voltage of an N-channel type transistor and a P-channel type transistor in the inverter circuit is, for example, 0.3 V, a minimum driving voltage of the oscillation circuit


412


is 0.7 V.




Next, an explanation will be given of the constitution of the 1st step-up circuit


430


.




In reference to

FIG. 46

, the start voltage input terminal


450


of the step-up circuit


410


is connected to the drain of an N-channel type MOS transistor


490


and connected to the source of an N-channel type transistor


492


. The 1st pulse signal input terminal


494


is connected to the gate of the N-channel type MOS transistor


492


and connected to the gate of an N-channel type MOS transistor


496


. The second pulse signal input terminal


498


is connected to the gate of the N-channel type MOS transistor


490


and connected to the gate of an N-channel type MOS transistor


502


. The source of the N-channel type MOS transistor


490


is connected to the drain of the N-channel type MOS transistor


496


and connected to a 2nd electrode of a capacitor


504


. A 1st electrode of the capacitor


504


is connected to the drain of the N-channel type MOS transistor


492


and connected to the source of the N-channel type MOS transistor


502


. An output terminal


506


for outputting the stepped-up voltage is connected to the drain of the N-channel type MOS transistor


502


. A GND terminal


508


is connected to the source of the N-channel type MOS transistor


496


. Therefore, according to the 1st step-up circuit


430


, the stepped-up voltage is constituted to be output from the output terminal


506


.




Next, an explanation will be given of the operation of the 1st step-up circuit


430


.




First, when the 1st pulse signal input from the 1st pulse signal input terminal


494


is “HIGH”, the 2nd pulse signal input from the 2nd pulse signal input terminal


498


becomes “LOW”, the N-channel type MOS transistors


492


and


496


are made ON and the N-channel type MOS transistors


490


and


502


are made OFF. Voltage supplied to the start voltage input terminal


450


is supplied to the 1st electrode of the capacitor


504


via the N-channel type MOS transistor


492


and the 1st electrode of the capacitor


504


is stepped up to voltage Va. GND voltage is supplied to the 2nd electrode of the capacitor


504


via the N-channel type MOS transistor


496


and the 2nd electrode of the capacitor


504


becomes “LOW”.




Next, when the 1st pulse signal input from the 1st pulse signal input terminal


494


is “LOW”, the 2nd pulse signal input from the 2nd pulse signal input terminal


498


becomes “HIGH”, the N-channel type MOS transistors


492


and


496


are made OFF and the N-channel type MOS transistors


490


and


502


are made ON. Voltage supplied to the start voltage input terminal


450


is supplied to the 2nd electrode of the capacitor


504


via the N-channel type MOS transistor


490


and the 2nd electrode of the capacitor


504


is stepped up to voltage Vb. The 1st electrode of the capacitor


504


is stepped up to voltage produced by adding the voltages Va and Vb. The stepped-up voltage is supplied to the output terminal


506


via the N-channel type MOS transistor


502


and voltage of the output terminal


506


is stepped up to Vc.




Values of the voltages Va, Vb and Vc have a relationship with a maximum voltage value which can be flowed between the source and the drain when the N-channel type MOS transistor is made ON. According to the N-channel type MOS transistor, when voltage applied between the source and the drain is equal to or lower than the maximum voltage value, any small voltage can be applied. However, according to the N-channel type MOS transistor, in the case in which the voltage applied between the source and the drain is higher than the maximum voltage value, even when large voltage is applied, only voltage having the maximum voltage value can be applied.




That is, when voltage supplied from the start voltage input terminal


450


is equal to or lower than the maximum voltage value of the N-channel type MOS transistor


492


, voltage supplied from the start voltage input terminal


450


and Va become the same as each other. When the voltage supplied from the start voltage input terminal


450


is higher than the maximum voltage value of the N-channel type MOS transistor


492


, Va becomes the maximum voltage value of the N-channel type MOS transistor


492


.




Further, when the voltage supplied from the start voltage input terminal


450


is equal to or lower than the maximum voltage value of the N-channel type MOS transistor


490


, the voltage supplied from the start voltage input terminal


450


and Vb become the same as each other. When the voltage supplied from the start voltage input terminal


450


is higher than the maximum voltage value of the N-channel type MOS transistor


490


, Vb becomes the maximum voltage value of the N-channel type MOS transistor


490


.




Further, when voltage produced by adding Va and Vb generated at the 1st electrode of the capacitor


504


is equal to or lower than the maximum voltage value of the N-channel type MOS transistor


502


, Vc becomes voltage produced by adding Va and Vb. When the voltage produced by adding Va and Vb generated at the 1st electrode of the capacitor


504


is higher than the maximum voltage value of the N-channel type MOS transistor


502


, Vc becomes the maximum voltage value of the N-channel type MOS transistor


502


.




In this case, the “maximum voltage value” of each of the N-channel type MOS transistors mentioned above is voltage produced by subtracting the threshold voltage from voltage of “HIGH” of each pulse signal input to the gate of each of the N-channel type MOS transistors, that is, voltage applied to the N-channel type MOS transistor.




By constituting the 1st step-up circuit


430


in this way, even when input voltage to be stepped up is low, the 1st step-up circuit


430


can step up the voltage efficiently. The constitution is effective particularly when voltage of the start voltage input terminal


450


is lower than the threshold voltage of the N-channel type MOS transistor.




Although the 1st step-up circuit


430


is constituted such that simultaneously with when the MOS transistor which has been made ON is made OFF, the MOS transistor which has been made OFF is made ON, by constituting the 1st step-up circuit


430


such that the MOS transistor which has been made ON is made OFF, thereafter, the MOS transistor which has been made OFF is made ON, feedthrough current can be eliminated and the efficiency of the stepping up voltage can be promoted.




Next, an explanation will be given of the constitution of the 2nd step-up circuit


432


.




In reference to

FIG. 47

, an input terminal


510


of the 2nd step-up circuit


432


connected to the output terminal


506


of the 1st step-up circuit


430


is connected to the drain of an N-channel type MOS transistor


520


and connected to the source of an N-channel type MOS transistor


522


. The 1st pulse signal input terminal


524


is connected to the gate of the N-channel type MOS transistor


522


, connected to the gate of an N-channel type MOS transistor


526


and connected to the gate of a P-channel type MOS transistor


532


. The 2nd pulse signal input terminal


528


is connected to the gate of the N-channel type MOS transistor


520


. The source of the N-channel type MOS transistor


520


is connected to the drain of the N-channel type MOS transistor


526


and connected to a 2nd electrode of a capacitor


534


. A 1st electrode of the capacitor


534


is connected to the drain of the N-channel type MOS transistor


522


and connected to the drain of the P-channel type MOS transistor


536


. An output terminal


536


for outputting stepped-up voltage is connected to the source of the P-channel type MOS transistor


532


grounded to the substrate. A GND terminal


538


is connected to the source of the N-channel type MOS transistor


526


. Therefore, the 2nd step-up circuit


432


is constituted such that stepped-up voltage is output from the output terminal


536


.




Next, an explanation will be given of the operation of the 2nd step-up circuit


432


.




First, when the 1st pulse signal input from the 1st pulse signal input terminal


524


is “HIGH”, the 2nd pulse signal input from the 2nd pulse signal input terminal


528


becomes “LOW”, the N-channel type MOS transistors


522


and


526


are made ON and the N-channel type MOS transistor


520


and the P-channel type MOS transistor


532


are made OFF. Voltage supplied to the input terminal


510


is supplied to the 1st electrode of the capacitor


534


via the N-channel type MOS transistor


522


and the 1st electrode of the capacitor


534


is stepped up to voltage Va


1


. GND voltage is supplied to the 2nd electrode of the capacitor


534


via the N-channel type MOS transistor


526


and the 2nd electrode of the capacitor


534


becomes “LOW”.




Next, when the 1st pulse signal input from the 1st pulse signal input terminal


524


is “LOW”, the 2nd pulse signal input from the 2nd pulse signal input terminal


528


becomes “HIGH”, the N-channel type MOS transistors


522


and


526


are made OFF and the N-channel type MOS transistor


520


and the P-channel type MOS transistor


532


are made ON. The voltage supplied to the input terminal


510


is supplied to the 2nd electrode of the capacitor


534


via the N-channel type MOS transistor


520


and the 2nd electrode of the capacitor


534


is stepped up to voltage Vb


1


. Therefore, the 1st electrode of the capacitor


534


is stepped up to voltage produced by adding the voltages Va


1


and Vb


1


. The stepped-up voltage is supplied to the output terminal


536


via the P-channel type MOS transistor


532


and voltage of the output terminal


536


is stepped up to Vc


1


.




In this case, there are two operational modes in the P-channel type MOS transistor


532


when the voltage of the 1st electrode of the capacitor


534


is lower than a minimum voltage value capable of flowing current between the source and the drain of the P-channel type MOS transistor


532


.




That is, when voltage at the 1st electrode of the capacitor


534


is less than 0.6 V (that is, voltage for flowing current in the forward direction from the drain of the P-channel type MOS transistor


532


toward the substrate), the voltage cannot be supplied to the output terminal


536


. When the voltage at the 1st electrode of the capacitor


534


is equal to or higher than 0.6 V and less than the minimum voltage value capable of flowing current between the source and the drain of the P-channel type MOS transistor


532


, voltage of “(voltage of 1st electrode of capacitor


534


)−(0.6 V)” is supplied to the output terminal


536


.




By contrast, in the case in which the voltage at the 1st electrode of the capacitor


534


is equal to or higher than the minimum voltage value capable of flowing current between the source and the drain of the P-channel type MOS transistor


532


, whatever the voltage at the 1st electrode of the capacitor


534


is, the voltage can be supplied to the output terminal


536


.




In this case, the “minimum voltage value capable of flowing current between the source and the drain of the P-channel type MOS transistor


532


” mentioned above is a value of voltage of the gate of the P-channel type MOS transistor


532


subtracted by the threshold voltage of the P-channel type MOS transistor


532


. Therefore, the “minimum voltage value” of the P-channel type MOS transistor


532


shown by

FIG. 47

is a value produced by subtracting the threshold value from the “LOW” voltage value of the gate of the P-channel type MOS transistor


532


, that is, a value produced by subtracting the threshold voltage from GND potential. As a result, the “minimum voltage value” of the P-channel type MOS transistor


532


becomes “an absolute value of the threshold value voltage”.




By constituting the 2nd step-up circuit


432


in this way, the 2nd step-up circuit


432


is featured in being capable of stepping up voltage efficiently when the voltage of the input terminal is equal to or higher than the minimum voltage value of the P-channel type MOS transistor


532


.




Although the 2nd set-up circuit


432


is constituted such that simultaneously with when the MOS transistor which has been made ON is made OFF, the MOS transistor which has been made OFF is made ON, by constituting the 2nd step-up circuit


432


such that the MOS transistor which has been made ON is made OFF, thereafter, the MOS transistor which has been made OFF is made ON, feedthrough current can be eliminated and the efficiency of the stepping up voltage can be promoted.




Next, an explanation will be given of the constitution of the 3rd step-up circuit


434


.




In reference to

FIG. 48

, an input terminal


540


of the 3rd step-up circuit


434


connected to the output terminal


536


of the 2nd step-up circuit


432


is connected to the source of the P-channel type MOS transistor


550


grounded to the substrate and connected to the drain of a P-channel type MOS transistor


552


. The 1st pulse signal input terminal


554


is connected to the gate of the P-channel type MOS transistor


550


, connected to the gate of the P-channel type MOS transistor


562


and connected to the gate of an N-channel type MOS transistor


556


. The 2nd pulse signal input terminal


558


is connected to the gate of the P-channel type MOS transistor


552


. The drain of the P-channel type MOS transistor


550


is connected to the drain of the N-channel type MOS transistor


556


and connected to a 2nd electrode of a capacitor


564


. A 1st electrode of the capacitor


564


is connected to the source of the P-channel type MOS transistor


552


grounded to the substrate and connected to the drain of the P-channel type MOS transistor


562


. An output terminal


566


for outputting stepped-up voltage is connected to the source of the P-channel type MOS transistor


562


grounded to the substrate. A GND terminal


568


is connected to the source of the N-channel type MOS transistor


556


. Accordingly, the 3rd step-up circuit


434


is constituted such that stepped-up voltage is output from the output terminal


566


.




Next, an explanation will be given of the operation of the 3rd step-up circuit


434


.




First, when the 1st pulse signal input from the 1st pulse signal input terminal


554


is “HIGH”, the 2nd pulse signal input from the 2nd pulse signal input terminal


558


becomes “LOW”, the N-channel type MOS transistor


556


and the P-channel type MOS transistor


552


are made ON and the P-channel type MOS transistors


550


and


562


are made OFF. Voltage supplied to the input terminal


540


is supplied to the 1st electrode of the capacitor


564


via the P-channel type MOS transistor


552


and the 1st electrode of the capacitor


564


is stepped up to voltage Va


2


. GND voltage is supplied to the 2nd electrode of the capacitor


564


via the N-channel type MOS transistor


556


and the 2nd electrode of the capacitor


564


becomes “LOW”.




Next, when the 1st pulse signal input from the 1st pulse signal input terminal


554


is “LOW”, the 2nd pulse signal input from the 2nd pulse signal input terminal


558


becomes “HIGH”, the N-channel type MOS transistor


556


and the P-channel type MOS transistor


552


are made OFF and the P-channel type MOS transistors


550


and


562


are made ON. The voltage supplied to the input terminal


540


is supplied to the 2nd electrode of the capacitor


564


via the P-channel type MOS transistor


550


and the 2nd electrode of the capacitor


564


is stepped up to the voltage Vb


2


. Therefore, the 1st electrode of the capacitor


564


is stepped up to voltage produced by adding together the voltages Va


2


and Vb


2


. The stepped-up voltage is supplied to the output terminal


566


via the P-channel type MOS transistor


562


and voltage of the output terminal


566


is stepped up to Vc


2


.




In this case, when the voltage of the 1st electrode of the capacitor


564


is lower than a minimum voltage capable of flowing current between the source and the drain of the P-channel type MOS transistor, voltage cannot be stepped up efficiently. By contrast, when the voltage at the 1st electrode of the capacitor


564


is higher than the minimum voltage capable of flowing current between the source and the drain of the P-channel type MOS transistor, whatever the voltage at the 1st electrode of the capacitor


564


is, the voltage can be supplied to the output terminal


566


.




Although the 3rd step-up circuit


434


is constituted such that simultaneously with when the MOS transistor which has been made ON is made OFF, the MOS transistor which has been made OFF is made ON, by constituting the 3rd step-up circuit


434


such that the MOS transistor which has been made ON is made OFF, thereafter, the MOS transistor which has been made OFF is made ON, feedthrough current can be eliminated and the efficiency of stepping up voltage can be promoted.




Next, an explanation will be given of the constitution of the 4th step-up circuit


436


.




In reference to

FIG. 49

, an input terminal


570


of the 4th step-up circuit


436


is connected to the output terminal


566


of the 3rd step-up circuit


434


. An output terminal


596


for outputting stepped-up voltage is connected to the source of a P-channel type MOS transistor


562


grounded to the substrate. Therefore, the 4th step-up circuit


436


is constituted such that the stepped-up voltage is output from the output terminal


596


. The constitution of other portion of the 4th step-up circuit


436


is the same as the constitution of that of the 3rd step-up circuit


414


mentioned above. Therefore, a detailed explanation of the constitution of other portion of the 4th step-up circuit


436


will be omitted.




Next, an explanation will be given of the operation of the 4th step-up circuit


436


. The operation of the 4th step-up circuit


436


is the same as the operation of the 3rd step-up circuit


434


mentioned above.




That is, first, when the 1st pulse signal input from the 1st pulse signal input terminal


554


is “HIGH”, the 2nd pulse signal input from the 2nd pulse signal input terminal


558


becomes “LOW”, the N-channel type MOS transistor


556


and the P-channel type MOS transistor


552


are made ON and the P-channel type MOS transistors


550


and


562


are made OFF. Voltage supplied to the input terminal


570


is supplied to the 1st electrode of the capacitor


564


via the P-channel type MOS transistor


552


and the 1st electrode of the capacitor


564


is stepped up to voltage Va


3


. GND voltage is supplied to the 2nd electrode of the capacitor


564


via the N-channel type MOS transistor


556


and the 2nd electrode of the capacitor


564


becomes “LOW”.




Next, when the 1st pulse signal input from the 1st pulse signal input terminal


554


is “LOW”, the 2nd pulse signal input from the 2nd pulse signal input terminal


558


becomes “HIGH”, the N-channel type MOS transistor


556


and the P-channel type MOS transistor


552


are made OFF and the P-channel type MOS transistors


550


and


562


are made ON. The voltage supplied to the input terminal


570


is supplied to the 2nd electrode of the capacitor


564


via the P-channel type MOS transistor


550


and the 2nd electrode of the capacitor


564


is stepped up to voltage Vb


3


. Therefore, the 1st electrode of the capacitor


564


is stepped up to voltage produced by adding together the voltages Va


3


and Vb


3


. The stepped-up voltage is supplied to the output terminal


596


via the P-channel type MOS transistor


562


and voltage at the output terminal


596


is stepped up to Vc


3


.




In this case, when the voltage at the 1st electrode of the capacitor


564


is lower than the minimum voltage capable of flowing current between the source and the drain of the P-channel type MOS transistor, voltage cannot be stepped up efficiently. By contrast, when the voltage at the 1st electrode of the capacitor


564


is higher than the minimum voltage capable of flowing current between the source and the drain of the P-channel type MOS transistor, whatever the voltage at the 1st electrode of the capacitor


564


is, the voltage can be supplied to the output terminal


596


.




Although the 4th step-up circuit


436


is constituted such that simultaneously with when the MOS transistor which has been made ON is made OFF, the MOS transistor which has been made OFF is made ON, by constituting the 4th step-up circuit


436


such that MOS transistor which has been made ON is made OFF and thereafter, the MOS transistor which has been made OFF is made ON, feedthrough current can be eliminated and the efficiency of stepping up voltage can be promoted.




As has been described, the step-up circuit


410


shown by

FIG. 44

is constituted by the 1st step-up circuit


430


, the 2nd step-up circuit


432


, the 3rd step-up circuit


434


and the 4th step-up circuit


436


. According to the step-up circuit


410


constituted in this way, voltage stepped up by the 1st step-up circuit


430


is further stepped up by the 2nd step-up circuit


432


. Voltage stepped up by the 2nd step-up circuit


432


is further stepped up by the 3rd step-up circuit


434


. Voltage stepped up by the 3rd step-up circuit


434


is further stepped up by the 4th step-up circuit


436


.




Further, according to the step-up circuit


410


constituted in this way, the N-channel type MOS transistors and the P-channel type MOS transistors are arranged at pertinent locations in accordance with the features respectively provided to them. As a result, even when the voltage at the start power terminal


450


is equal to or lower than the minimum drive voltage of the oscillation circuit


412


, the voltage at the start power terminal


450


can be stepped up by the 1st step-up circuit


430


and the stepped-up voltage can further be stepped up by the 2nd step-up circuit


432


, the 3rd step-up circuit


434


and the 4th step-up circuit


436


.




In reference to FIG.


43


through

FIG. 45

again, when the output voltage Vp from the thermoelectric generator unit


180


is changed over time from a state in which the output voltage Vp is not output (output voltage=0 V) and exceeds the minimum driving voltage of the oscillation circuit


412


, the output voltage Vp from the thermoelectric generator unit


180


is input to the oscillation circuit power supply terminal


480


of the oscillation circuit


412


via the Schottky diode


414


. Thereby, the oscillation circuit


412


starts operation and oscillation is started.




The oscillation circuit


412


which has started oscillation outputs the pulse signal to the pulse signal output terminal


476


and the output pulse signal is input to the pulse signal input terminal of the step-up circuit


410


. The step-up circuit


410


starts stepping up the output voltage from the thermoelectric generator unit


180


by inputting the pulse signal. Under the state, the step-up voltage output terminal


452


of the step-up circuit


410


and the oscillation circuit power supply terminal


480


of the oscillation circuit


412


are connected to each other and accordingly, the stepped-up voltage constitutes power supply of the oscillation circuit


412


. The Schottky diode


414


is connected between the output terminal of the thermoelectric generator unit


180


and the oscillation circuit power supply terminal


480


and accordingly, once the oscillation circuit


412


is operated and starts stepping up voltage, the oscillation circuit


412


uses voltage stepped up by the step-up circuit


410


as power supply. Accordingly, once the output voltage Vp of the thermoelectric generator unit


180


exceeds the minimum driving voltage of the oscillation circuit


412


, even when the output voltage Vp from the thermoelectric generator unit


180


is changed by elapse of time and becomes lower than the minimum driving voltage of the oscillation circuit


412


, the step-up circuit


410


can continue stepping up voltage.




In the constitution, voltage of the storage member


420


can also be used as oscillation start voltage of the oscillation circuit


412


. In this case, the voltage of the storage member


420


is supplied to the oscillation circuit power supply terminal


480


via the power supply operation control circuit


416


to thereby start oscillation of the oscillation circuit


412


. Once the oscillation circuit


412


is operated to start stepping up voltage, similar to the above-described operation, the oscillation circuit


412


uses the voltage stepped up by the step-up circuit


410


as power supply.




The power supply operation control circuit


416


inputs the stepped-up voltage Vpp and distributes power to the timepiece driving circuit


418


and the storage member


420


in accordance with a value of the stepped-up voltage Vpp.




When the stepped-up voltage Vpp is equal to voltage necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies the timepiece driving circuit


418


with the voltage stepped up by the step-up circuit


410


.




When the stepped-up voltage Vpp is voltage larger than the voltage necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies the voltage stepped up by the step-up circuit


410


to both of the timepiece driving circuit


418


and the storage member


420


.




When the stepped-up voltage Vpp is voltage smaller than the voltage necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies voltage from the storage member


420


to the timepiece driving circuit


418


.




By constituting to operate the power supply operation control circuit


416


in this way, even when the stepped-up voltage Vpp becomes voltage smaller than the voltage capable of driving the timepiece driving circuit


418


, the timepiece driving circuit


418


can continue driving by voltage from the storage member


420


. Accordingly, by the constitution, the output voltage of the thermoelectric generator unit


180


can be utilized efficiently.




(6) Operation of an Embodiment of a Timepiece Having the Thermoelectric Generator Unit According to the Invention




According to an embodiment of a timepiece having the thermoelectric generator unit according to the invention, in reference to

FIG. 42

, the output voltage from the thermoelectric generator unit


180


is input to the step-up circuit


410


or the power supply operation control circuit


416


. The voltage stepped up by the step-up circuit


410


is supplied to the timepiece driving circuit


418


.




The timepiece driving circuit


418


includes a timepiece driving oscillation circuit, a timepiece driving dividing circuit and a motor driving circuit. The crystal oscillator


602


constitutes the oscillation source, is oscillated at, for example, 32,768 Herz and outputs a reference signal to the timepiece driving oscillation circuit. The timepiece driving dividing circuit inputs the output signal from the oscillation circuit, carries out predetermined dividing operation and outputs a signal of, for example, 1 Herz. The motor driving circuit inputs the output signal from the timepiece driving dividing circuit and outputs a drive signal for driving the step motor.




The timepiece driving circuit


418


is operated by voltage stepped up by the step-up circuit


410


or voltage of the secondary battery


600


. The power supply operation control circuit


416


controls to supply voltage stepped up by the step-up circuit


410


to the timepiece driving circuit


418


and supply voltage of the secondary battery


600


to the timepiece driving circuit


418


.




The coil block


610


inputs a drive signal output from the motor driving circuit for driving the step motor and magnetizes a plurality of poles of the stator


612


. The rotor


614


is rotated by magnetic force of the stator


612


. The rotor


614


is rotated by 180 degree per second based on a 1 Herz signal mentioned above.




The fifth wheel & pinion is rotated by rotation of the rotor


614


. The fourth wheel & pinion


618


is rotated by 6 degree per second by rotation of the fifth wheel & pinion


616


. The third wheel & pinion


620


is rotated by rotation of the fourth wheel & pinion


618


. The center wheel & pinion


622


is rotated by rotation of the third wheel & pinion


620


. The minute wheel


624


is rotated by rotation of the center wheel & pinion


622


. The hour wheel


622


is rotated by rotation of the minute wheel


624


.




“Second” is displayed by the second hand


640


attached to the fourth wheel & pinion


618


. “Minute” is displayed by the minute hand


642


attached to the center wheel & pinion


622


. “Hour” is displayed by the hour hand


646


attached to the hour wheel


626


.




In reference to FIG.


20


and

FIG. 50

, when a timepiece having the thermoelectric generator unit according to the invention is worn by the arm, heat of the arm


650


is transferred to the case back


226


. Heat of the case back


226


is transferred to the 1st thermally conductive plate


120


of the thermoelectric generator unit


180


via the thermal conductive spacer


320


. That is, the 1st thermally conductive plate


120


constitutes a heat absorbing plate. The electrothermic elements


140


of the thermoelectric generator unit


180


generates electromotive force by the Seebeck effect. Therefore, the 2nd thermally conductive plate


170


of the thermoelectric generator unit


180


constitutes a heat radiating plate. Heat radiated from the 2nd thermally conductive plate


170


is transferred to the upper case body


220


via the thermal conductive body


244


and is discharged to outside air


652


.




In reference to

FIG. 20

, the thermal conductive body


244


is brought into contact with the projected portions


220




a


of the upper case body


220


. According to the constitution, as mentioned above, by using the flat thermal conductive body


244


, heat can be transferred extremely efficiently from the 2nd thermally conductive plate


170


to the projected portions


220




a


of the upper case body


220


. That is, by the constitution in which the flat thermal conductive body


244


is brought into contact with the projected portions


220




a


of the upper case body


220


, thermal resistance in a heat radiating path can be reduced. Accordingly, the power generating efficiency of the thermoelectric generator unit can be promoted by the constitution.




According to an embodiment of a timepiece having the thermoelectric generator unit of the invention, the electrothermic element


140


is constituted to connect in series, for example, 10 pairs of modules including 50 pairs of PN junctions and the threshold voltage of the transistors included in the oscillation circuit


412


and the step-up circuit


410


is constituted to be 0.3.




According to an embodiment of a timepiece having the thermoelectric generator unit for the invention, a power generation amount of one piece of an electrothermic material element constituting the thermoelectric generator unit


140


is, for example, about 200 μV/° C. Accordingly, when the operation voltage of the timepiece is set to 1.5 V, in order to drive the timepiece directly by the thermoelectric generator unit, when a difference between temperatures of the 1st thermally conductive plate


120


and the 2nd thermally conductive plate


170


is 2° C., there is needed the electrothermic element


140


having 18125 pairs of PN junctions.




However, the embodiment of the timepiece having the thermoelectric generator unit of the invention is constituted to include the step-up circuit


410


, the oscillation circuit


412


and the power supply operation control circuit


416


described above and accordingly, in the case in which power generating voltage immediately after the timepiece is worn by the arm exceeds the minimum drive voltage of the oscillation circuit


412


, even when power generating voltage in a later steady state becomes voltage lower than the minimum drive voltage of the oscillation circuit


412


, voltage can be stepped up by the step-up circuit


410


.




For example, according to an experiment in respect of an embodiment of a timepiece having the thermoelectric generator unit of the invention, the power generating voltage immediately after the timepiece was worn by the arm was 2 V and the power generating voltage in a later steady state was 0.5 V. According to the embodiment of the timepiece having the thermoelectric generator unit of the invention, when the threshold voltage of the transistors included in the oscillation circuit


412


was about 0.3 V, the minimum drive voltage of the oscillation circuit


412


was about 0.7 V.




For example, according to the embodiment of the timepiece having the thermoelectric generator unit of the invention, as mentioned above, the power supply operation control circuit


416


inputs the stepped-up voltage Vpp and distributes power to the timepiece driving circuit


418


and the storage member


420


in accordance with a value of the stepped-up voltage Vpp.




When the stepped-up voltage Vpp falls in a range of voltage of 1.2 V through 1.5 V necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies the timepiece driving circuit


418


with voltage stepped up by the step-up circuit


410


.




When the stepped-up voltage Vpp is voltage larger than voltage 1.5 V necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies voltage stepped-up by the step-up circuit


410


to both of the timepiece driving circuit


418


and the storage member


420


.




When the stepped-up voltage Vpp is voltage smaller than voltage 1.2 V necessary for driving the timepiece driving circuit


418


, the power supply operation control circuit


416


supplies voltage from the secondary battery


600


to the timepiece driving circuit


418


.




By constituting the power supply operation control circuit


416


in this way, even when the stepped-up voltage Vpp becomes voltage smaller than voltage capable of driving the timepiece driving circuit


418


, the timepiece driving circuit


418


can be continued to be driven by voltage from the secondary battery


600


. Accordingly, by the constitution, even when the stepped-up voltage becomes smaller than voltage 1.2 V necessary for driving the timepiece driving circuit


418


, the timepiece can be continued to be driven.




(7) A Structure of an Embodiment of an Electronic Device Having the Thermoelectric Generator Unit According to the Invention




In reference to FIG.


51


and

FIG. 52

, according to an embodiment of a portable electronic device having the thermoelectric generator unit of the invention, a portable electronic device


700


is installed with a liquid crystal panel


710


, a speaker


712


and a lamp


718


.




A drive control circuit


720


is operated by voltage supplied from the power supply operation circuit


416


. According to the embodiment, the constitutions and operations of the thermoelectric generator unit


180


, the step-up circuit


410


, the oscillation circuit


412


, the power supply operation circuit


416


, the secondary battery


600


and the crystal oscillator, are the same as those of the embodiment of the timepiece having the thermoelectric generator unit of the invention mentioned above. Accordingly, a detailed explanation thereof will be omitted.




The drive control circuit


720


is constituted to count information in respect of time, information in respect of alarm time and information in respect of elapsed time based on oscillation of the crystal oscillator


602


. A display control circuit


730


outputs a signal for operating the liquid crystal panel


710


to the liquid crystal panel


710


based on a signal output from the drive control circuit


720


. Accordingly, the liquid crystal panel


710


displays information in respect of time or time period based on a signal output from the display control circuit


730


.




A speaker control circuit


732


outputs a signal for operating the speaker


712


to the speaker


712


based on a signal output from the drive control circuit


720


. The speaker


712


emits alarm sound at time to emit the alarm sound based on a signal output from the speaker control circuit


732


. Sound emitted by the speaker


712


is emitted from a sound emitting hole


712




a


to outside of the portable electronic device


700


.




There are provided 4 of buttons, that is, a 1st button


740


, a 2nd button


742


, a 3rd button


744


and a 4th button


746


for operating the portable electronic device


700


. In

FIG. 51

, only the 1st button is shown. A 1st switch terminal


750


is installed to carry out operation of a switch by pushing to operate the 1st button


740


. A 2nd switch terminal


752


is installed to carry out operation of a switch by pushing to operate the 2nd button


742


. A 3rd switch terminal


754


is installed to carry out operation of a switch by pushing to operate the 3rd button


744


. A 4th switch terminal


756


is installed to carry out operation of a switch by pushing to operate the 4th button


746


. The operation of the switch is carried out when the respective switch terminal provides an input signal to the corresponding switch input terminal of the drive control circuit


720


.




A lamp control circuit


738


outputs a signal for turning on the lamp


718


to the lamp


718


based on a signal output from the drive control circuit


720


. For example, the lamp control circuit


738


is constituted to operate by pushing the 4th button


746


for turning on the lamp


718


.




According to the embodiment of the electronic device having the thermoelectric generator unit of the invention, the portable electronic device


700


may be provided with only the liquid crystal panel


710


, may be provided with the liquid crystal panel


710


and the speaker


712


, may be provided with the liquid crystal panel


710


and the lamp


718


and may be provided with the liquid crystal panel


710


, the speaker


712


and the lamp


718


.




Further, the portable electronic device


700


may further be provided with the timepiece driving circuit shown by FIG.


42


and the hands operated by the timepiece driving circuit. By constituting the portable electronic device


700


in this way, there can be realized a composite display type portable electronic device having both of analog type display and digital type display.




There can be realized a digital wrist watch by constituting the portable electronic device


700


such that time information is displayed on the liquid crystal panel


710


.




Further, there can be realized an alarm or a timepiece having alarm by constituting the portable electronic device


700


such that the speaker


712


emits alarm sound at previously set time.




Further, there can be realized a timer or a timepiece having timer by constituting the portable electronic device


700


such that the speaker


712


emits alarm sound when a previously set period of time has elapsed.




INDUSTRIAL APPLICABILITY




As has been explained above, the invention is constituted such that in the timepiece having the thermoelectric generator unit a heat transferring path of a thermally conductive body is shortened and, accordingly, there is provided a timepiece having a thermoelectric generator unit with excellent power generating efficiency.



Claims
  • 1. A timepiece comprising:a case back made of a thermally conductive material; an upper case body made of a thermally conductive material and disposed opposite to the case back; a lower case body made of a thermally insulating material and disposed between the upper case body and the case back; a thermoelectric generator unit for generating an electromotive force in accordance with heat conducted from the case back; at least one step-up circuit for stepping up the electromotive force generated by the thermoelectric generator unit; a storage member for storing power and for storing the electromotive force stepped up by the step-up circuit; a timepiece driving circuit driven by power stored in the storage member or by electromotive force stepped up by the step-up circuit; a power supply operating control circuit for controlling a power flow from the step-up circuit to the storage member and for controlling whether the electromotive force stepped up by the step-up circuit or the power stored in the storage member is supplied to the timepiece driving circuit; and a display member for displaying time information in accordance with a signal output from the timepiece driving circuit.
  • 2. A timepiece according to claim 1; wherein the power supply operating control circuit supplies the electromotive force stepped up by the step-up circuit to the timepiece driving circuit and the storage member when a voltage of the electromotive force stepped up by the step-up circuit is larger than a driving voltage of the timepiece driving circuit, and supplies the power stored in the storage member to the timepiece driving circuit when the voltage of the electromotive force stepped up by the step-up circuit is smaller than the driving voltage of the timepiece driving circuit.
  • 3. A timepiece according to claim 1; wherein the at least one step-up circuit comprises a plurality of step-up circuits connected to each other.
  • 4. A timepiece according to claim 1; wherein the thermoelectric generator unit comprises at least one thermoelectric element, a first thermally conductive plate, a second thermally conductive plate, and a thermal conductive body made of a thermally conductive material and disposed between and in contact with the second thermally conductive plate and the upper case body.
  • 5. A timepiece according to claim 4; wherein the upper case body has a projecting portion extending in a direction toward the case back for conducting heat to the thermal conductive body.
  • 6. A timepiece according to claim 5; wherein the thermal conductive body is generally plate-shaped.
  • 7. A timepiece according to claim 4; wherein the first thermally conductive plate comprises a heat absorbing plate; and wherein the second thermally conductive plate comprises a heat radiating plate.
  • 8. A timepiece according to claim 1; wherein the thermoelectric generator unit comprises at least one thermoelectric element, a first thermally conductive plate, a second thermally conductive plate, and a thermal conductive spacer made of a thermally conductive material and disposed in contact with and between the first thermally conductive plate and the case back.
  • 9. A timepiece according to claim 8; wherein the thermal conductive spacer is made of a compressible material and is maintained in a compressed state between the first thermally conductive plate and the case back.
  • 10. A timepiece according to claim 8; wherein the first thermally conductive plate comprises a heat absorbing plate; and wherein the second thermally conductive plate comprises a heat radiating plate.
  • 11. A timepiece according to claim 1; wherein the thermoelectric generator unit comprises at least one thermoelectric element, a frame surrounding the thermoelectric element, a first thermally conductive plate disposed on a first side of the frame, and a second thermally conductive plate disposed on a second side of the frame opposite the first side.
  • 12. A timepiece according to claim 11; wherein the first thermally conductive plate comprises a heat absorbing plate; and wherein the second thermally conductive plate comprises a heat radiating plate.
  • 13. A timepiece comprising:a case back made of a thermally conductive material; an upper case body made of a thermally conductive material and having a projecting portion extending towards the case back; a lower case body made of a thermally insulating material for insulating the case back from the upper case body; a thermoelectric generator unit for generating power in accordance with heat conducted from the case back, the thermoelectric generator unit having a first thermally conductive plate and a second thermally conductive plate; a heat conductor disposed in contact with both the projecting portion of the upper case body and the second thermally conductive plate of the thermoelectric generator unit so that heat is conducted between the upper case body and the heat conductor; and a heat conductive spacer disposed in contact with both an inner surface of the case back and the first thermally conductive plate of the thermoelectric generator.
  • 14. A timepiece according to claim 13; further comprising at least one step-up circuit for stepping up the electromotive force generated by the thermoelectric generator unit, a storage member for storing power and for storing the electromotive force stepped up by the step-up circuit, a timepiece driving circuit driven by power stored in the storage member or by electromotive force stepped up by the step-up circuit, a power supply operating control circuit for controlling a power from the step-up circuit to the storage member and for controlling whether the electromotive force stepped up by the step-up circuit or the power stored in the storage member is supplied to the timepiece driving circuit, and a display member for displaying time information in accordance with a signal outputted from the timepiece driving circuit.
  • 15. A timepiece according to claim 14; wherein the power supply operating control circuit supplies the electromotive force stepped up by the step-up circuit to the timepiece driving circuit and the storage member when a voltage of the electromotive force stepped up by the step-up circuit is larger than a driving voltage of the timepiece driving circuit, and supplies the power stored in the storage member to the timepiece driving circuit when the voltage of the electromotive force stepped up by the step-up circuit is smaller than the driving voltage of the timepiece driving circuit.
  • 16. A timepiece according to claim 14; wherein the at least one step-up circuit comprises a plurality of step-up circuits connected to each other.
  • 17. A timepiece according to claim 13; wherein the first thermally conductive plate of the thermoelectric generator comprises a heat absorbing plate; and wherein the second thermally conductive plate of the thermoelectric generator comprises a heat radiating plate.
  • 18. A timepiece according to claim 13; wherein the heat conductive spacer is made of a compressible material and is maintained in a compressed state between the inner surface of the case back and the first thermally conductive plate of the thermoelectric generator.
Priority Claims (4)
Number Date Country Kind
9-280925 Oct 1997 JP
9-358074 Dec 1997 JP
10-42543 Feb 1998 JP
10-249328 Sep 1998 JP
PCT Information
Filing Document Filing Date Country Kind
PCT/JP98/04589 WO 00
Publishing Document Publishing Date Country Kind
WO99/19776 4/22/1999 WO A
US Referenced Citations (12)
Number Name Date Kind
4106279 Martin et al. Aug 1978 A
4213292 Dolezal et al. Jul 1980 A
5705770 Ogasawara et al. Jan 1998 A
5889735 Kawata et al. Mar 1999 A
5974002 Tsubata Oct 1999 A
6075757 Kawata Jun 2000 A
6172943 Yuzuki Jan 2001 B1
6222114 Mitamura Apr 2001 B1
6259656 Kotanagi Jul 2001 B1
6304520 Watanabe Oct 2001 B1
6304521 Kanesaka Oct 2001 B1
6320208 Kanesaka Nov 2001 B1