Electronic component with built-in push switch driven by rotary and pushing operation of an operating knob

Information

  • Patent Grant
  • 6229103
  • Patent Number
    6,229,103
  • Date Filed
    Thursday, August 6, 1998
    26 years ago
  • Date Issued
    Tuesday, May 8, 2001
    23 years ago
Abstract
An operation type electronic component which is used for a remote controller of various electronic equipment and portable electronic equipment and is equipped with a push switch driven by the rotating and push operation of an operation knob. The component can be reduced in size and grounded by a simple construction and can be grounded by merely fitting. A dome-like movable contact (23E) is put on fixed contacts (23A, 23B) disposed on a fitting substrate (22) to form a switch unit (23). An L-shaped actuator is interposed between this switch unit (23) and a driving body (21) so that the driving body (21) returns to the original state after the push operation of an operation knob (6) by the elastic operation force of the dome-like movable contact point (23E)of the switch unit (23). Further, a metal plate (25) equipped integrally with a live current portion (10) and a conductor of an earth portion (26) is fixed by insert-molding to the resin fitting substrate (22) and is electrically isolated so as to interpose a lightning conductor portion (26A) of the earth portion (26) between the live current portion (10) and the operation knob (6). According to this constitution, the number of constituent components can be reduced, the overall size can be reduced, too, and static electricity occurring in the operation knob (6) can be always conducted to the earth.
Description




FIELD OF TECHNOLOGY




The present invention relates to an operation type electronic component with built-in push switch driven by rotating operation and push operation of an operating knob, which operation type electronic component being a component mainly used in remote controllers of various electronic appliances or in portable electronic devices.




BACKGROUND TECHNOLOGIES




A rotary encoder with built-in push switch, which is an embodiment of a prior art operation type electronic component with push switch, is described hereunder referring to

FIGS. 9 through 13

.




A prior art rotary encoder with built-in push switch comprises, as shown in

FIG. 9

(cross sectional view) and

FIG. 10

(partially cutaway top view), a movable member


1


affixed movable to a base board


2


in holding part


1


C, a rotary contact wheel


3


attached revolvable on the movable member


1


and disposed at the middle part of the base board


2


, and a switch


4


disposed at a rear part of base board


2


(at the right in FIGS.


9


-


10


).




The rotary contact wheel


3


is provided at the bottom surface with contact plates


3


A disposed in a radial arrangement for accepting contacts from elastic contact reeds


5


of the base board


2


, and held revolvable at the central hole


3


B by a pillar


1


A of the movable member


1


, with the top covered with an operating knob


6


that rotates together.




As shown in a perspective view of

FIG. 11

, the base board


2


comprises a hole


2


A provided in a side part for holding the movable member


1


movable, a hollow


2


C having a stop wall


2


B for fixing the switch


4


, elastic contact reeds


5


for generating electric signal by having contact with the bottom surface of rotary contact wheel


3


, and terminals


7


for taking the generated electric signal out.




A coil spring


8


, which is positioned by an extrusion


2


D located on the base board


2


at a rear part, pushes a side of the movable member


1


in horizontal direction so that push rod


1


B of the movable member


1


is usually kept off the switch


4


. Switch


4


is, as shown in

FIG. 9

, fixed in the hollow


2


C of base board


2


with the rear end touching to the stop wall


2


B, and a button


4


A facing to the push rod


1


B of movable member


1


.




The operation of the above prior art rotary encoder having push switch is described in the following.




The rotary contact wheel


3


rotates with the pillar


1


A of movable member


1


as the axis when the knob


6


attached on the rotary contact wheel


3


is rotated by a force given in tangential direction indicated with an arrow F in FIG.


10


. The radial contact plates


3


A disposed on the bottom surface of rotary contact wheel


3


slide on the elastic contact reeds


5


of base board


2


, and pulse signals are generated. The pulse signals are outputted through the terminals


7


, thus it works as a rotary encoder.




While the operating knob


6


is being rotated, a pushing force is also given to the knob, but the spring force of said twisted coil spring


8


prevents the push rod


1


B of movable member


1


from pushing the button


4


A of switch


4


.




When the operating knob


6


is pressed in the direction of an arrow G in

FIG. 10

with more force than the force due to the coil spring


8


, the entire part of the movable member


1


including the rotary contact wheel


3


is moved to the direction of an arrow H with the holding part


1


C of movable member


1


, or a hole


2


A of the base board


2


, as the axis of movement, causing the push rod


1


B of movable member


1


push the button


4


A to actuate the switch


4


. As soon as the force given to the knob


6


is withdrawn, the force of twisted coil spring


8


pushes the movable member


1


back to the original position.




The above described prior art rotary encoder having push switch employs an independent completed switch for the switch


4


that works on a push of the operating knob


6


, and comprises the coil spring


8


disposed at a rear part of the base board


2


for preventing the push rod


1


B of movable member


1


from pushing the switch


4


while the operating knob


6


is being rotated, as well as for restoring the movable member


1


to the original position when the pushing operation on the operating knob


6


is finished. These result in a higher cost and an increased body size of a rotary encoder having push switch.




In the general trends towards the more compact and lower price of electronic appliances, those electronic components to be incorporated in such appliances are likewise requested to be compact yet have advanced functions, coming in low price. A means to meet the requirement is to make the components available on an automatic production line. A popular solution is introduction of an insert-shaping technique, wherein contact points, terminals and other conductive members are formed on a hoop of metal sheet to be inserted into a resin molded base board, for the later assembly on an automatic assembly machine.




Now in the following, a method of manufacturing a base board containing contacts, terminals and other conductive members is described with reference to

FIG. 12

, using the above mentioned prior art rotary encoder having push switch as the vehicle.





FIG. 12

illustrates a metal sheet hoop showing a set of conductive members formed on the metal sheet and a resin molded base board with the set of conductive members inserted therein. Numeral


9


denotes an electro-conductive metal sheet hoop provided with frame alley


9


A, and


10


conductive members stamped in flat sheet form with each of the members remaining connected with the frame alley


9


A at connecting sections


9


B. Numeral


2


denotes a resin molded base board with the conductive members


10


inserted therein.




In the next step, the base board


2


undergoes a cutting at the joints


10


A of conductive members


10


, and then the conductive members


10


are formed to become elastic contact reeds


5


. Then, the sections


9


B connecting with the frame alley


9


A are cut at cutting lines


9


C, and the terminals


7


are bent downward to complete a base board


2


as shown in FIG.


11


.




The cut surface


11


of electro-conductive metal sheet


9


is exposed out of the surface of base board


2


in the above prior art method. When a rotary encoder


12


having push switch


12


assembled with the above base board


2


is mounted on a circuit board


14


with a part of the operating knob


6


extruding out of outer casing


13


, and the cut surface is positioned at a vicinity of the operating knob


6


, a static electricity generated while the operating knob


6


is rotated with a finger discharges to the cut surface


11


. The discharge affects the signals to be outputted from a rotary encoder having push switch


12


, producing possible causes of erroneous operation of an apparatus.




In prior art methods, therefore, the cut surface


11


had to be covered with a separate metal board


15


electrically coupled with a ground sector


16


of apparatus by means of soldering etc., whenever there is a possibility of the electrostatic problem. This is a substantial drawback that results in an extra parts count and additional assembly steps.




DISCLOSURE OF THE INVENTION




The present invention is intended to solve the above described problems the prior arts had, and to present an operation type electronic component which has a simple structure enabling the reduction of the total dimensions and cost, wherein the grounding work is completed at a same time with a mounting work.




An operation type electronic component according to the present invention comprises a switch which is constituted by providing a dome shape moving contact point on a fixed contact point prepared on base board, and an L-shaped actuator disposed between the switch and a movable member; wherein the elastic force of the dome shape moving contact point is utilized to prevent the movable member from actuating the switch while an operating knob is being rotated, the elastic force is also used to return the movable member to the original position after a push operation to the knob is finished. Further, according to the present invention, the conductive members and the grounding member which are provided on a same metal sheet are fixed in a resin mold base board by means of an insert-shaping technique, and then the electrical coupling between the conductive members and the grounding member is broken; thus the grounding member is placed between the conductive members and the knob.




With the above described constitution, the total number of constituent parts including the parts constituting the switch is reduced, which enables the reduction of cost and the overall size of an operation type electronic component, furthermore the static electricity generated at the knob is always discharged to a nearest electro-conductive substance, viz. the grounding member.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a cross sectional view showing a rotary encoder having push switch according to an embodiment of an operation type electronic component of the present invention,





FIG. 2

a partially cutaway top view of the above rotary encoder,





FIG. 3

a perspective view of the key part of the above rotary encoder, viz. base board,





FIG. 4

a perspective view of the key part of the above rotary encoder, viz. L-shaped actuator,





FIG. 5

a cross sectional view of the key part of the above rotary encoder showing how the L-shaped actuator is attached to the base board,





FIG. 6

a cross sectional view of the above rotary encoder showing when the knob is being pushed,





FIG. 7

a top view of metal sheet hoop showing the conductive members and grounding member formed on the hoop, and these members after insert-molded in a resin mold base board,





FIG. 8

a cross sectional side view of the above rotary encoder having push switch mounted in a casing.





FIG. 9

is a cross sectional view showing a prior art rotary encoder having push switch,





FIG. 10

a partially cutaway top view of the above rotary encoder,





FIG. 11

a perspective view of the key part of the above rotary encoder, viz. the base board,





FIG. 12

a top view of prior art metal sheet hoop showing the conductive members formed on the hoop and these members after insert-molded in a resin mold base board,





FIG. 13

a cross sectional side view of the above rotary encoder having push switch mounted in a casing.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




An operation type electronic component according to an embodiment of the present invention is described below using a rotary encoder having push switch as the vehicle, referring to FIG.


1


through FIG.


8


. In the drawings, those constituent parts having the same functions as those of the above described prior art are given with the same symbols, and explanation to which is omitted.




As shown in FIG.


1


and

FIG. 2

, a rotary encoder having built-in push switch according to the present invention comprises a movable member


21


affixed movable to a base board


22


at holding part


21


B, a rotary contact wheel


3


affixed revolvable on the movable member


21


and disposed at the middle part of the base board


22


, and a switch


23


disposed at a rear part of base board


22


(at the right in FIGS.


1


-


2


). This constitution is similar to that of the prior art.




The rotary contact wheel


3


is provided at the bottom surface with contact plates


3


A disposed in a radial arrangement for accepting the contact from elastic contact reeds


5


of the base board


22


, and held revolvable at the central hole


3


B by a pillar


21


A of the movable member


21


with the top covered with an operating knob


6


that rotates together. This constitution is similar to that of the prior art, too.




As shown in perspective view of FIG.


3


. the base board


22


comprises a hole


22


A for holding the movable member


21


movable, elastic contact reeds


5


for generating electric signal by having contact with the bottom surface of rotary contact wheel


3


, and terminals


7


for taking the generated electric signal out. Within a hollow


22


B of the base board


22


, a pair of fixed contact points


23


A and


23


B for switch


23


are provided, and switch terminals


23


C and


23


D electrically coupled respectively with these contact points at an outer circumferential part. A pit


22


C for affixing the L-shaped actuator


24


is provided in a central part of base board


22


at an outskirt of the hollow


22


B. The L-shaped actuator


24


for actuating the switch


23


is comprised of arms of board form


24


A and


24


B, approximately rectangular to each other, and a holding pivot


24


C located at the crossing part, as shown in FIG.


4


.




A method of assembling a rotary encoder having built-in push switch according to the present embodiment is described in the following. A domed movable contact point


23


E is attached on the outer fixed contact point


23


A disposed in the hollow


22


B located at a rear part of base board


22


, covering the inner fixed contact point


23


B, and then a flexible film


23


F for dust-free is applied over the domed movable contact point to complete a switch


23


.




The L-shaped actuator is affixed in the pit


22


C of base board


22


in the following method. The holding pivot


24


C is pushed into the pit


22


C of base board


22


at the enlarged part


22


D (see FIG.


2


and

FIG. 3

) with the arm


24


A of L-shaped actuator


24


perpendicular to the base board


22


, and the arm


24


B facing to switch


23


, upon reaching the floor


22


E of pit the holding pivot


24


C is made to go horizontally in order to bring the entire body of L-shaped actuator


24


towards the switch


23


. The holding pivot


24


C goes beyond a small bump


22


F to be fixed into a cavity


22


H formed by the pit floor


22


E and a ceiling wall


22


G, as shown with an arrow line in FIG.


5


. In this way the L-shaped actuator


24


is held movable with the holding pivot


24


C as the axis. The bottom surface of arm


24


B keeps touching with the top of the domed movable contact


23


E of said switch


23


via the flexible film


23


F.




The movable member


21


is coupled with the base board


22


by inserting the holding part


21


B of movable member


21


provided at an end into a hole


22


A from underneath which is provided in the base board


22


at an end, then an extrusion


21


D at the end of an arm


21


C located in a rear end of the movable member


21


will touch to an end of arm


24


A of said L-shaped actuator


24


. The rotary contact wheel


3


is attached revolvable to the movable member


21


at pillar


21


A, and then the operating knob


6


is mounted to complete a rotary encoder with built-in push switch according to the present embodiment.




Now in the following, the operation of a rotary encoder with built-in push switch according to the present embodiment is described.




Pulse signals are generated by rotating the operating knob


6


with a force given in the tangential direction as indicated with an arrow J in

FIG. 2

; by the rotation of rotary contact wheel


3


with the pillar


21


A of movable member


21


as the center of rotation the radial contact plates


3


A disposed on the bottom surface of rotary contact wheel


3


slide on the elastic contact reeds


5


of base board


22


to generate the pulse signals. The pulse signals are led to the outside through the terminals


7


providing a function as a rotary encoder. This operation is similar to that in the prior art.




During the above rotating operation of knob


6


. although an element of the force given to the knob in the push-in direction, or the force given to the movable member


21


, reaches the domed movable contact point


23


E of switch


23


via the arm


21


C of movable member


21


and the L-shaped actuator


24


, the switch


23


is not put into operation because the elastic force of domed movable contact


23


E is set to be strong enough to resist the element of force.




When the operating knob


6


is pressed in the direction as indicated by an arrow K in FIG.


2


and

FIG. 6

with a force strong enough to overcome the force due to the elastic force of said domed movable contact


23


E of switch


23


, the rotary contact wheel


3


and the entire movable member


21


move to the direction as indicated by an arrow L with the holding part


21


B of movable member


21


, viz. the hole


22


A of base board


22


, as the axis. Then, the extrusion


21


D provided at the end of arm


21


C of movable member


21


pushes the end of arm


24


A of L-shaped actuator


24


making the L-shaped actuator


24


rotate in the direction shown by an arrow M in

FIG. 6

around the holding pivot


24


C. The end tip of arm


24


B pushes the top of the domed movable contact point


23


E of switch


23


firmly downward. As the result, the domed movable contact point


23


E is reversed with snapping action, and the fixed contact point


23


A and the fixed contact point


23


B, or the switch terminals


23


C and


23


D, are shortcircuited as shown in FIG.


6


.




As soon as the push-in force given to the knob


6


is withdrawn, the arm


24


B of L-shaped actuator


24


is pushed up by the elastic restoring force of the domed movable contact point


23


E, and movable member


21


, rotary contact wheel


3


, and knob


6


are pushed back to the original position as shown in FIG.


1


and FIG.


2


.




The force needed to push the knob


6


in depends on the elastic restoring force of the domed movable contact point


23


E, and the relationship between the push-in force and the push-in stroke of the knob


6


are adjustable through adjustment of the location at which the arm


21


C of movable member


21


presses the arm


24


A of L-shaped actuator


24


, and the location at which the arm


24


B presses the domed movable contact point


23


E of switch


23


. When the arm


21


C is provided at a rear end of movable member


21


and the extrusion


21


D at the end of the arm is made to press the extreme end of arm


24


A of L-shaped actuator


24


, as in the present embodiment, the push-in stroke becomes the largest.




A method of manufacturing the base board


22


according to the present invention is shown in FIG.


7


. Where, numeral


25


denotes a hoop of electro-conductive metal sheet on which a gathering of the conductive members


10


and the grounding part


26


as well as the fixed contact points


23


A and


23


B for switch tied with the frame


25


A and the conductive members


10


by means of the connecting sections


25


B is continually stamped. Numeral


22


denotes a resin-molded base board in which the conductive members


10


, the grounding part


26


, and the fixed contact points


23


A and


23


B for switch are inserted.




In the base board


22


thus formed, the conductive members


10


, the elastic contact reeds


5


, and the terminals


7


are shaped in the same way as in the prior art. And then, the connecting sections


25


B of the grounding part


26


are cut at the cutting places


25


C; of which a plate


26


A to work as a lightning rod is bent upward, while plates


26


B to become grounding terminals are bent downward, and the fixed contact points


23


A and


23


B for the switch are separated by cutting the cutting section


25


D; and a base board


22


as shown in

FIG. 3

is completed.




A rotary encoder with built-in push switch made with the base board


22


is mounted on an apparatus as shown in

FIG. 8

, where the grounding terminals


26


B are electrically coupled with a circuit board


14


of the apparatus at the ground sector


16


, furthermore the grounding part


26


is located at a place closest to the outer surface of apparatus casing


13


. By so mounting, the lightning rod


26


A of grounding part


26


becomes an electro-conductive substance located closest to the operating knob


6


, therefore the static electricity always jumps onto the lightning rod


26


A and escapes to the grounding wire through the grounding terminals


26


B. Thus the grounding is ensured without providing the metal board


15


, which was indispensable with the prior arts.




In FIG.


3


and

FIG. 8

both describe the present embodiment, the plate to become lightning rod


26


A of grounding part


26


is bent upward, while the plates to become the grounding terminals


26


B downward; however, it is of course possible to dispose the plates for lightning rods


26


A up in the right and left, whereas the plate for grounding terminal


26


B down in the middle.




Furthermore, according to the present constitution, as the output terminals


7


, the grounding terminals


26


B, and the switch terminals


23


C/


23


D are taken out to be formed and disposed in a same direction with almost equivalent dimensions, while the grounding part is built in a rotary encoder having push switch, the accuracy of terminal arrangement is high enough to undergo the automatic assembly, which enables to further reduce the number of steps for assembling an apparatus.




In the above embodiment, descriptions have been made using a rotary encoder having built-in push switch, which being an embodiment of the operation type electronic component, as the vehicle. However, it is of course possible to apply the above base board manufacturing method to the manufacture of normal operation type electronic components having no push switch.




USABILITY IN THE INDUSTRY




According to the present invention, a switch is constituted with fixed contact points provided on the base board of an operation type electronic component and a dome shaped movable contact point placed over the fixed contact points, and an L-shaped actuator is disposed between the switch and a movable member having an operating knob; thereby the movable member is prevented from putting the switch into operation during rotating operation of the knob by making use of the elastic force of the dome shaped movable contact point of switch, meanwhile the same elastic force is utilized for returning the movable member to the original position as soon as the push-in operation of knob is over. The conductive members and the grounding parts stamped in a same metal sheet are once fixed in a resin molded base board by means of an insert-molding method, and then electrically separated afterwards; this brings about a grounding part positioned between the conductive members and the operating knob.




By taking the above described constitution, the total number of constituent components including those of the switch are reduced enabling to reduce the cost and the overall size of an operation type electronic component. Furthermore, by simply mounting a base board prepared through the above method on a circuit board of an apparatus an operation type electronic component is presented, wherein the static electricity generated from operating knob always escapes to the grounding part which is an electro-conductive substance located closest to the knob.



Claims
  • 1. An electronic component comprising:a resin mold body in which a conductive member comprised of a contact point and a terminal is housed; an operating knob for switching an electrical signal to be generated at said conductive member by operating an outer circumference portion of said operating knob; and a grounding electro-conductive substance for removing static electricity generated in the operating knob, insert-molded within said resin mold body so as to be positioned near the outer circumference portion of said operating knob between the outer circumference portion of said operating knob and said conductive member.
  • 2. The electronic component of claim 1, wherein said conductive member and said grounding electro-conductive substance are formed on a common metal material to be insert-molded in said resin mold body, and then said conductive member and said grounding electro-conductive substance are electrically separated after being molded in said resin mold body.
  • 3. The electronic component of claim 2, wherein said terminal of said conductive member and a terminal of said grounding electro-conductive substance extend out of the resin mold body in a common directional arrangement at approximately a common length.
  • 4. The electronic component of claim 1, wherein said terminal of said conductive member and a terminal of said grounding electro-conductive substance extend out of the resin mold body in a common directional arrangement at approximately a common length.
  • 5. The electronic component of claim 1, wherein said grounding electro-conductive substance includes a lightning rod terminal extending upward from an upper main surface of said resin mold body, and a grounding terminal extending downward from a lower main surface of said resin mold body.
  • 6. An electronic component comprising:a rotary contact wheel having an operating knob and a plurality of contact elements; a resin mold body in which a conductive member is molded, said resin mold body having an upper main surface and a lower main surface, and said conductive member including an elastic reed for generating an electrical signal by elastically contacting with a contact element of said rotary contact wheel and a terminal for taking said electrical signal out; a movable member which holds said rotary contact wheel removable and is coupled with said resin mold body part so as to be movable in parallel with said upper main surface of the resin mold body; a switch comprised of a fixed contact point molded at an end part of said resin mold body and a dome shaped movable contact point placed over the fixed contact point; an L-shaped actuator for activating said switch and including a first arm perpendicular to the main surface of said resin mold body and touching an edge of said movable member, a second arm extending perpendicular from said first arm, parallel with the main surface of said resin mold body, towards said switch and contacting the dome shaped movable contact point of the switch, and a pivot for revolvably attaching said L-shaped actuator to said resin mold body, said pivot being positioned adjacent where said first and second arms meet; and a grounding electroconductive substance insert-molded within said resin mold body and positioned between an outer circumference of said operating knob and said conductive member, said grounding electro-conductive substance including a lightning rod terminal extending upward from and perpendicular to said upper main surface of said resin mold body, and a grounding terminal extending downward from and perpendicular to said lower main surface.
  • 7. An electronic component comprising:a rotary contact wheel having an operating knob and a plurality of contact points; a resin mold body in which a conductive member is molded, said conductive member including an elastic reed and a terminal for taking an electrical signal out, the electrical signal being generated when the elastic reed elastically contacts with a contact point of said rotary contact wheel; a movable member which holds said rotary contact wheel revolvable and is coupled with said resin mold body so as to be movable in parallel with a main surface of the resin mold body; a switch comprised of a fixed contact point molded at an end part of said resin mold body and a dome shaped movable contact point placed over the fixed contact point; an L-shaped actuator for actuating said switch and including a first arm perpendicular to the main surface of said resin mold body and touching an edge of said movable member, a second arm extending perpendicular from said first arm, parallel with the main surface of said resin mold body, towards said switch and contacting the dome shaped movable contact point of the switch, and a pivot for revolvably attaching said L-shaped actuator to said resin mold body, said pivot being positioned adjacent where said first and second arms meet; and a grounding electro-conductive substance for removing static electricity generated in the operating knob, insert-molded within said resin mold body so as to be positioned near an outer circumference portion of said operating knob between the outer circumference of said operating knob and said conductive member.
  • 8. The electronic component of claim 7, wherein an extrusion is provided at a certain part of an outer circumference of said movable member for contacting with said first arm at an end point of said L-shaped actuator.
  • 9. The electronic component of claim 8, wherein said L-shaped actuator is attached to the resin mold body by first inserting said pivot vertically into a pit provided in said resin mold body and then lightly pushing in a horizontal direction towards said switch.
  • 10. The electronic component of claim 7, wherein said L-shaped actuator is attached to the resin mold body by first inserting said pivot vertically into a pit provided in said resin mold body and then lightly pushing in a horizontal direction towards said switch.
Priority Claims (2)
Number Date Country Kind
7-214391 Aug 1995 JP
8-072702 Mar 1996 JP
PCT Information
Filing Document Filing Date Country Kind 102e Date 371c Date
PCT/JP96/01821 WO 00 8/6/1998 8/6/1998
Publishing Document Publishing Date Country Kind
WO97/08720 3/6/1997 WO A
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