This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-207879 filed on Dec. 22, 2021, the entire content of which is incorporated herein by reference.
The present disclosure relates to an electronic device including a solar cell.
Some low-power electronic devices or portable electronic devices, such as electronic watches, are provided with panel-shaped solar cells (solar panels) and operate with electric power generated by the solar cells. Among these, small electronic devices are required to make light efficiently incident on their solar cells and transmit generated electric power to power supply circuits of their circuit boards or the like.
In JP 2013-213719 A, as a technology for easily arranging solar panels with flexibility, there is disclosed a power generating device including: two solar sections each having a plurality of solar panels arranged flatwise; and a bendable coupling section connecting these to one another, wherein the coupling section is integrated with the solar sections.
An electronic device includes:
a solar cell;
a wiring board including a feeder wiring connected to the solar cell;
a connector continuous with the wiring board and including a feeder electrode electrically connected to the feeder wiring;
a first circuit including a first electrode and a first wiring continuous with the first electrode;
a second circuit including a second electrode and a second wiring continuous with the second electrode; and
a fixing member that fixes the feeder electrode, the first electrode and the second electrode in a state in which the electrodes are superposed on top of one another, to electrically connect each one of the electrodes to another one or more of the electrodes.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure, wherein:
Hereinafter, one or more embodiments of the present disclosure will be described with reference to the drawings.
The electronic timepiece 1 includes a case 12, a dial 13, hands 14, a dial cover 15 (parting member), and a board 20 (circuit board). Through the dial cover 15, a solar panel 16 (solar cell) disposed thereunder is visible. The hands 14 are covered, from the above, with a light-transmitting, transparent in this embodiment, crystal 17 (light-transmitting member, shown in
The abovementioned conventional technology has a problem that the area for connecting and fixing a solar cell to a circuit board or the like takes up much space.
The present disclosure is for solving such a problem, and hereinafter an electronic device capable of supplying generated electric power in a more space-saving manner, namely with less space, will be described.
The case 12 is cylindrical with the upper end and the lower end open. In the circular space (i.e., inside the case 12), for example, the following are housed; the dial 13, the hands 14, the dial cover 15 and the board 20, which are mentioned above, and a drive unit including a wheel train mechanism, which is a gear train, and a stepping motor that rotate the hands 14, and a battery 22 (rechargeable battery). The lower end of the case 12 is sealed with the back cover 18 (shown in
The dial 13 is disposed so as to be exposed to the upper end side of the case 12. On the upper surface (exposed surface) of the dial 13, indexes 131 (hour marks) for indicating time are disposed for respective hours (at intervals of 30 degrees). On the upper surface of the dial 13, marks for indicating time in units of minutes and seconds may also be disposed, for example.
The center of the dial 13 is the rotational axis of at least some of the hands 14, for example, an hour hand, a minute hand and a second hand. The other hands 14 may be small hands that rotate in small windows 132 that occupy part of the upper surface of the dial 13.
The dial 13 and the hands 14 constitute a display of this embodiment.
The dial cover 15 is an annular member disposed along the upper end of the inner circumferential surface of the case 12, and defines, from above the dial 13, a visible area of the dial 13 that a user can see. The “along the upper end of the inner circumferential surface” herein does not mean being in contact with the upper end. The upper surface of the dial cover 15 may be disposed lower than the upper end of the case 12. The dial cover 15 of the electronic timepiece 1 of this embodiment is a light-transmitting member, such as resin. The dial cover 15 does not need to be transparent, and may be a colored light-transmitting member.
The solar panel 16 is a solar cell formed of a plurality of solar cells arranged in line to be annular, and disposed under the dial cover 15 to receive light incident thereon through the dial cover 15, thereby generating electric power. The solar panel 16 may be a film-like panel, which is thinner and less rigid than a plate-like panel.
The board 20 is disposed on the back surface side (lower side) in the case 12 (on a plane different from that on which the solar panel 16 is disposed), substantially parallel to the solar panel 16 in this embodiment. To the board 20, a connector 162 continuous with a wiring plate 161, disposed at the tip of the wiring plate 161 in this embodiment, extending from the solar panel 16 is connected and fixed, so that electric power is supplied to the board 20, and electronic components connected thereto operate. The board 20 includes a CPU (microcomputer) or the like. Operation of the CPU includes operation as an electronic timepiece, namely operation as a time counter that counts current time and operation as a display controller that causes the drive unit (motor), which rotates the hands 14 in sync with the current time, to operate to cause the hands 14 to display the current time.
Inside the case 12, the drive unit for the hands 14 and the board 20 are disposed under the dial 13. The open lower surface (lower end) of the case 12 is sealed with the back cover 18. To the upper end of the inner circumferential surface of the case 12, the transparent crystal 17 is fitted.
The upper portion of the inner circumferential surface of the case 12 is stepwise outward, and the upper end of this portion forms an opening (open upper end/surface) of the case 12. The solar panel 16 is disposed on an annular step surface 121 with which the stepwise portion is provided. The inner diameter of the case 12 above the step surface 121 is larger than that of the case 12 under the step surface 121. The dial cover 15 disposed above the solar panel 16 is fitted in the large space, which is above the step surface 121 of the case 12, along the inner circumferential surface of the case 12 via an annular packing 19. That is, the dial cover 15 is not in direct contact with the case 12. The packing 19 is an elastic member and may be waterproof. The packing 19 deforms so as to fill the gap between the case 12 and the dial cover 15, thereby fixing the dial cover 15 to the case 12 appropriately.
The lower end of the packing 19 reaches the step surface 121, and the outer edge of the solar panel 16 is interposed and fixed between the packing 19 and the step surface 121. This makes it unnecessary to use an adhesive, such as glue or double-sided tape, to fix the solar panel 16, and accordingly does not cause deterioration in external appearance of the electronic timepiece 1 due to an adhesive being visible through the dial cover 15. Further, since no adhesive is used, the solar panel 16 hardly slides from its original position, in particular, hardly leaves the step surface 121 and comes into contact with the dial cover 15.
The packing 19 is partly interposed between the solar panel 16 and the dial cover 15, thereby separating the solar panel 16 and the dial cover 15 from one another. For this purpose, the sectional shape of the packing 19 may be L-shaped as shown in
The packing 19 is an elastic member as described above, for example, a resin member, such as rubber. The stepwise portion of the inner circumferential surface of the case 12 has an annular depression 122 in a portion with which the packing 19 comes into contact. The packing 19 pressed by fitting of the dial cover 15 partly expands into the depression 122. This prevents (or reduces) the packing 19 from expanding and protruding upward along the inner circumferential surface of the case 12, and accordingly, if not prevents, reduces deterioration in the external appearance of the electronic timepiece 1 viewed from the above (i.e., from the upper surface side).
To the solar panel 16, the wiring plate 161 (wiring board), one end thereof in this embodiment, is connected, and the wiring plate 161 curvedly extends downward from this one end along the inner circumferential surface of the case 12 in the sectional view. With the wiring plate 161, the connector 162 is continuous, and a (pair of) feeder electrode(s) 1622 (shown in
The board 20 includes a main circuit board 201 (first circuit board) to which the CPU or the like is connected and a motor board 202 (second circuit board) for the motor of the drive unit. The electric power generated by the solar panel 16 is supplied to a power supply circuit of the main circuit board 201 and a power supply circuit of the motor board 202 in parallel via an electrode(s) of the main circuit board 201 and an electrode(s) of the motor board 202.
The wiring plate 161 may be integrated with the solar panel 16. In this embodiment, the solar panel 16 has a notch 1601 in its inner edge, and the wiring plate 161 branches off at and extends from the inside of the notch 1601. That is, where the wiring plate 161 branches off from the solar panel 16 is a position outward from the inner edge of the solar panel 16, which is annular. Hence, the wiring plate 161 does not greatly protrude inward from the inner edge of the solar panel 16, namely does not protrude or, even if it does, protrudes by a small width, without making the minimum value of curvature for the curved shape of the wiring plate 161 significantly small. The wiring plate 161 interferes with arrangement of internal components as little as possible.
The connector 162, which is continuous with the wiring plate 161, is substantially circular, and has a through hole 1621 in its center for the screw member 23 to pass through. Around the through hole 1621, the feeder electrode 1622 is disposed, and this feeder electrode 1622 is continuous with the feeder wiring 1611 (shown in
The solar panel 16, the wiring plate 161 and the connector 162 constitute a power generator of this embodiment.
As described above, the screw member 23 passes through the through hole 1621 of the connector 162 to fix (co-fasten) the connector 162 and boards, the main circuit board 201 and the motor board 202 in this embodiment, all together (in the state in which they are superposed on top of one another) from the underneath. On both surfaces of the main circuit board 201, which is disposed on a lower side (side close to the connector 162) between these two boards 201, 202, (pairs of) connector electrodes 2011 (first electrodes) are disposed. The connector electrode 2011 on the upper surface of the main circuit board 201 is invisible in
By co-fastening, the connector electrode 2011 on the upper surface of the main circuit board 201 is superposed on and comes into contact with the connector electrode 2021, thereby being electrically connected thereto. The connector electrodes 2011 are continuous with power supply lines 2012 (first wires or first wiring), and these constitute a first circuit 2010. The electric power supplied from the solar panel 16 to the first circuit 2010 via the feeder wiring 1611 of the wiring plate 161 is transmitted to a power supply unit and other components of the main circuit board 201. The connector electrode 2021 is continuous with a power supply line 2022 (second wire or second wiring), and these constitute a second circuit 2020. The electric power supplied from the solar panel 16 to the second circuit 2020 via the feeder wiring 1611 and the connector electrodes 2011 is transmitted to a motor drive unit or the like for the motor board 202. The feeder electrode 1622 is disposed on, of the connector 162, only the side (upper surface) that comes into contact with the board 20 (i.e., main circuit board 201), and the side (lower surface) that comes into contact with the bearing surface of the screw member 23 is made of an insulating member and hence is not electrically connected to the screw member 23.
Since two inter-electrode gaps are fixed together by one screw member 23, electric power can be supplied with certainty, without taking up much space.
In this modification, the solar panel 16a is configured such that a separate wiring plate 161a provided with a connector 162a is attached and fixed to a connector terminal 1602a. In this case, as shown in
As shown in
With the other end (tip) of the wiring plate 161a, the connector 162a is continuous. The connector 162a has a through hole 1621a in its center. The positional relationship between the wiring plate 161a and the connector 162a may be the same as or different from that of the wiring plate 161 and the connector 162.
The connector terminal 220 shown in
In this case, the power supply line(s) 2012 connected to the connector electrode 2011 on the upper surface of the main circuit board 201 and the power supply line(s) 2012 connected to the connector electrode 2011 on the lower surface of the main circuit board 201 are independently connected to the power supply unit (LSI, etc.) on the main circuit board 201. Further, in this case, the screw member 23 is insulating at least on its surface. The power supply unit charges or discharges the battery 22 depending on the magnitude of the output voltage of the battery 22 and the magnitude of the power generation voltage of the solar panel 16, for example. To each component of the main circuit board 201, electric power is supplied from either the battery 22 or the solar panel 16.
As described above, the electronic timepiece 1 of this embodiment includes: the solar panel 16; the wiring plate 161 including the feeder wiring 1161 connected to the solar panel 16; the connector 162 continuous with the wiring plate 161 and including the feeder electrode 1622 electrically connected to the feeder wiring 1611; the first circuit 2010 including the connector electrodes 2011 and the power supply lines 2012 continuous with the connector electrodes 2011; the second circuit 2020 including the connector electrode 2021 and the power supply line 2022 continuous with the connector electrode 2021; and the screw member 23 that fixes the feeder electrode 1622, the connector electrodes 2011 and the connector electrode 2021 in the state in which the electrodes 1622, 2011, 2021 are superposed on top of one another, to electrically connect each one of the electrodes 1622, 2011, 2021 to another one or more of the electrodes 1622, 2011, 2021.
Thus, the feeder electrode 1622 and other two or more electrodes are superposed on top of one another and co-fastened by one screw member 23 such that two or more inter-electrode connections are formed. This reduces space required for their connections, and more efficiently supplies electric power to each component of the electronic timepiece 1.
Further, the first circuit 2010 is disposed on the main circuit board 201, the second circuit 2020 is disposed on the motor board 202, and the screw member 23 fixes the connector 162, the main circuit board 201 and the motor board 202 in the state in which the connector 162, the main circuit board 201 and the motor board 202 are superposed on top of one another. Thus, the boards, on which the abovementioned electrodes are disposed, are fixed in the state of being superposed on top of one another. This reduces the number of screw members 23 to be used in the electronic timepiece 1 for connecting the boards having some thicknesses, and accordingly reduces the abovementioned space.
Further, the wiring plate 161 is integrated with the solar panel 16. Forming these components as a single unit is easier than not, and saves time and effort to attach the wiring plate 161 to the solar panel 16. In addition, such a wiring plate 161 is less likely to cause cut-off of electric power supply due to connection failure (e.g., poor contact).
Further, the wiring plate 161 may be bendable. This makes it easy to adjust the wiring path of the wiring plate 161. In particular, this wiring plate 161 can connect the solar panel 16 to the main circuit board 201 or the like even when they are misaligned slightly, and strain that is applied to the wiring plate 161 when they are connected is distributed appropriately. Hence, the wiring plate 161 makes it easy and simple to assemble the electronic timepiece 1. In addition, it is unlikely that durability of the wiring plate 161 greatly decreases.
Further, the solar panel 16 is annular and has the notch 1601 in its inner edge, and the wiring plate 161 extends from the notch 1601.
That is, the wiring plate 161 branches off from the solar panel 16 at a position outward from the inner edge of the solar panel 16. If the wiring plate 161 greatly protrudes inward, it could be an obstacle to arrangement of other electronic components or the like. The wiring plate 161 branching off from the solar panel 161 at a position outward from the inner edge of the solar panel 16 reduces the amount of the inward protrusion without being bent a steep angle, in particular, without being bent discontinuously, in other words, even by being bent gradually or being curved. The wiring plate 161 therefore hardly becomes an obstacle to arrangement of other components in the electronic timepiece 1, and at the same time, prevents trouble, such as cutting of the feeder wiring 1611 of the wiring plate 161.
Further, the fixing member, which fixes the connector 162, is the screw member 23 (threaded member), and the width of the joined portion of the wiring plate 161 and the connector 162 is larger than the width of the wiring plate 161, the widths being substantially perpendicular to the extending direction of the wiring plate 161. When the connector 162 is fixed by the screw member 23, force is likely to be applied to the connector 162 in its rotational direction. Making the root/base of the connector 162 wide improves durability of the connector 162 against the force in the torsional direction, and prevents trouble, such as wiring breakage.
Further, the center of the connector 162 is off the extension of the center line of the wiring plate 161. It is unnecessary for the wiring plate 161 and the connector 162 to form a straight line. Their positions (positional relationship) can be adjusted as appropriate in accordance with a positional relationship between (i) where the wiring plate 161 can pass through between the case 12 and the board 20 and (ii) where the connector 162 is actually fixed to the main circuit board 201. The connector 162 being off from the extension of the center line of the wiring plate 161 enhances durability of the connector 162 and the wiring plate 161 against the force in the torsional direction even if the force is applied to the connector 162 and the wiring plate 161.
The electronic timepiece 1 includes the CPU (microcontroller) on the main circuit board 201 as the time counter that counts the current time, and the display (dial 13 and hands 14) that displays the current time. Electronic timepieces are required to be small/lightweight and perform solid continuous operation. The electronic timepiece 1 is small and can supply electric power with certainty.
The present disclosure is not limited to the above embodiment, and various modifications can be made.
For example, in the above embodiment, the wiring plate 161 forms a straight line in its unfolded state, but not limited thereto. The wiring plate 161 may be bent in the unfolded state in its sliding direction.
Further, in the above embodiment, the feeder electrode 1622, the main circuit board 201 and another one type of electrode are co-fastened, but this is not a limitation. The feeder electrode 1622 and three or more types of electrode may be co-fastened. The order of their superposition is not limited to those described above either. For example, the feeder electrode 1622 and electrodes (terminals) may be co-fastened in the state in which the feeder electrode 1622 is interposed between the electrodes.
Further, the widths, thicknesses, sizes and so forth of the wiring plate 161 and the connector 162 may be set as appropriate to be suitable for the arrangement space inside the case 12, for example. Still further, the wiring plate 161 may not be wide partly but wholly. Yet further, the width of the wiring plate 161 may not be uniform. Further, the center of the connector 162 may be on the extension of the center line of the wiring plate 161.
Further, the solar panel 16 being integrated with the wiring plate 161 does not require itself to have the notch 1601. Still further, if there is some room not inside but outside the solar panel 16, the notch 161 may be provided in the outer edge of the solar panel 16.
Further, in the above embodiment, the connector 162 has the through hole 1621 in its center for the screw member 23 to pass through, but not limited thereto. For example, the connector 162 may have a U-shaped notch (recess) for the screw member 23 to pass through.
Further, the wiring board may not be plate-like (belt-shaped) like the wiring plate 161. For example, the sectional shape of the wiring board may be a circle, an oval, two circles joined together, a square, a square with rounded corners, or the like.
Further, the “annular” is not limited to being a perfect circle. The “annular” could indicate a shape having portions of different curvatures, steeply-bent portions (portions having angles) and/or straight portions.
Further, in the above embodiment, the solar panel 16 is disposed under the light-transmitting dial cover 15, but not limited thereto. For example, the solar panel 16 may be disposed under a light-transmitting portion of the dial 13. Still further, the solar panel 16 may be supported not by the step surface 121 of the case 12 but by another member. Yet further, the solar panel 16 may not be fixed by the packing 19 but adhesively fixed by an adhesive. Further, the solar panel 16 may not be completely circumferential or annular, but have some cuts in its annular shape.
Further, in the above embodiment, co-fastening is performed by the screw member 23 as the threaded member. However, even if the connector 162 (feeder electrode 1622), the main circuit board 201 (connector electrodes 2011), the motor board 202 (connector electrode 2021) and/or the like are fixed by another type of fixing member, such as solder, the thickness of these components as a whole can be made smaller, and accordingly the space required for their connections can be reduced.
Further, in the above embodiment, the wiring plate 161 is flexible, so that its curved shape is adjustable. However, if misalignment of the solar panel 16 and the main circuit board 201 or the like is unlikely to occur, the wiring plate 16 may have a fixed shape along the wiring path between, for example, the connection position thereof to the solar panel 16 and the connection position thereof to the main circuit board 201. Still further, the wiring plate 161 may be flat or have some steep bends.
Further, like the modification, if the connector electrodes on the boards 201, 202 that are electrically connected to one another but not to the feeder electrode 1622 are included in those co-fastened (fixed in the state of being superposed on top of one another), the connector electrodes do not transmit electric power therebetween, but may constitute a transmission path of another signal.
Further, although the electronic device of the above embodiment is the electronic timepiece 1, it may be another type of electronic device. Further, the electronic timepiece 1 may not have hands, but have a digital display screen to display time digitally.
Other specific configurations, components, contents and procedures of the processes, and so forth described in the above embodiment can be modified as appropriate without departing from the scope of the present disclosure.
Although one or more embodiments of the present disclosure have been described above, the scope of the present disclosure is not limited to the embodiments, but includes the scope of claims and the scope of their equivalents.
Number | Date | Country | Kind |
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2021-207879 | Dec 2021 | JP | national |