JPH0352919B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a circuit section used in an electronic wristwatch.

[Conventional technology and problems]

Conventionally, the structure of the circuit section used in electronic wristwatches has been constructed by mounting necessary electronic components on a circuit board made of ceramic, glass-epoxy resin, etc., and connecting them by patterns.

However, with the above-mentioned circuit boards, in addition to the thickness of the board itself, the height of the contact points with other components is limited, making it impossible to satisfy the growing need for thinner products. I've come to the point where I can't get it anymore.

Recently, flexible printed circuit boards have appeared in response to this thinning, and good results have been obtained. However, flexible printed circuit boards alone lack rigidity, and therefore have problems with ease of installation and retention after installation. Furthermore, in the case of the above-mentioned circuit board, there is no other suitable method for connecting points with other parts other than using screws, making it impossible to simplify the structure.

[Purpose of the invention]

The present invention has been made in view of the above points, and its object is to provide a circuit structure suitable for a thin watch and having a simple contact portion.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a plan view of the crystal oscillation wristwatch according to the present invention, viewed from the back cover side. At the upper right in the figure, a switching mechanism operated by a crown (not shown) and a needle setting mechanism are mainly arranged. The central part of the winding stem 7 is loosely fitted into a horizontal hole in the main plate 1, and a mandarin duck 8 is provided so as to straddle the winding stem 7. Mandarin duck 8
The cannula 9, which is screwed to and has a lattice 9b, is
The switching lever 10 is swung around the switching lever stud 10a planted on the base plate 1. Small railway car 1
1 and the intermediary wheel 12 that meshes with it are the switching lever 10
It is placed on. Mandarin duck 8 and switching lever 10
A back presser 13 that clamps a part of the
The pin 8a installed in the mandarin duck 8 is connected to two adjacent holes 13a which are determined by the spring force of the pin 8a in the upper and lower directions, and the battery 38 is pressed from the side to establish continuity and stabilize the position of the battery 38. Bending portion 13b
It is fixed to the base plate 1 with two screws. The former is a small and thin mechanism used as a moderation force generating mechanism for pulling out and pushing in the winding stem 7.
In the latter case, the plate thickness of the back presser 13 is just right, and it is effective in terms of cost and space because it can be used as a component. In the mandarin duck 8, a long hole 8b in a direction perpendicular to the axial direction of the winding stem 7 is loosely fitted into a shaft 1c planted in the main plate 1.
This is because, as will be described later, there is little clearance between the engagement portion of the winding stem 7 and the mandrel 8, and it is necessary to provide play in the longitudinal direction of the mandrel 8, that is, in the direction perpendicular to the axial direction of the winding stem 7. Therefore, even in a thin wristwatch like this embodiment, a highly reliable switching mechanism with sufficient engagement between the winding stem 7 and the mandrel 8 can be obtained. Furthermore, the mandarin duck 8 has a (+) spring 8c welded to the (+) lead portion 2 of the flexible sheet 25.
5a, and contacts the contact point 26, which is insulated and implanted in the base plate 1, by the spring force in the direction of its upper and lower surfaces. 1
d is a hole into which the dial leg loosely fits, 35b is a dial screw that presses and fixes the dial leg, and 37 is a mechanical screw that fixes the watch movement to the watch case (not shown). There is another one in a symmetrical position. The above-mentioned switching mechanism mainly includes the winding stem 7, mandrel 8, cannula 9, switching lever 10, back pusher 13, needle turning mechanism mainly consisting of the winding stem 7, small iron wheel 11, intermediate wheel 12, (+) spring 8c, contact 26
The switch mechanism, which is based on This makes the corresponding work easier.

An electromechanical converter serving as a prime mover is placed in the upper left portion of FIG. 1. The coil 19 is inserted into a slightly larger hole provided in the main plate 1, and the bent portions of both ends of the winding core 19a are tightly attached to the end portions of the stator 17, which is attached to the dial side of the main plate 1 with screws.
In addition to holding it by fixing it with e, there is a coil holder 2 made of polyacetal resin etc. in the center part.
9 and a silicone rubber 31 sandwiched between the base plate 1 and the coil 19. The structure of the upper left portion prevents deformation of the soft magnetic winding core 19a that occurs upon impact. A magnetic shield plate 30 is fixed with a pin 29a of the coil holder 29, and these integrated pieces are attached to the base plate 1 with screws 29b. 17a is a notch in the stator 17 that determines the initial position of the rotor 6, and is shaped to have the same effect, although it appears less sharply at a symmetrical position. A stator plate 18 is made of brass and has approximately the same shape as the stator 17. 20
is a terminal plate of a printed circuit board attached to a protruding portion of the coil winding core 19a that is remote from the magnetic circuit.

A deceleration wheel train and an indicator wheel train are shown in the center of FIG. 1, and in this embodiment, they are all housed in the lower surface of the main plate 1, that is, in the milled part on the dial side. The roll 6 of the prime mover is rotated by a stator 17 which receives an alternating magnetic flux excited by a coil 19. A fourth wheel & pinion 5, a third wheel & pinion 4, and a second wheel & pinion 3, which are a reduction gear train, decelerate the rotation of the rotor 6. The shaft supports in the upper surface direction of the rotor 6, fourth wheel 5, and third wheel 4 are polyacetal resin push-pieces that are pressed into the main plate 1, and may be used without lubrication, but it is better to apply a very small amount of lubrication to prevent rust. Good results can be obtained even in points. The shaft supports in the lower surface direction of the fourth wheel 5 and the third wheel 4 are bushes similar to those described above, which are embedded in the train wheel bridge 2 screwed to the lower surface of the main plate 1. The center wheel 3 is loosely fitted onto a central shaft 1a planted in the main plate 1. The indicator wheel train 15 and hour wheel 16 receive rotation from the deceleration wheel train. The Hino-ura wheel 15 is located between the main plate 1 and the Hino-ura support 14 screwed to the main plate 1, and is also rotated by the intermediary wheel 12 of the needle turning mechanism when setting the hands. Main plate 1
The hole 1h located at the position overlapping the rotor 6 is for checking the operation. The reduction gear train is almost invisible from the back cover side.

The bottom side of Figure 1 is the electronic circuit section, and the right side is the battery section. The circuit base 21 on which electronic circuit components are placed is
It is made of nickel silver, and a thin flexible conductive sheet 25 having a conductive pattern is attached to the bottom side. The circuit base 21 is placed on the milling part 1j of the base plate 1, and the upper surface of the base plate 1 is at the same height as the upper surface thereof, and is arranged substantially in a plane with the reduction gear train. 22 is a crystal oscillator, 23 is an IC chip,
24 is a temperature compensation capacitor, and 28 is a trimmer capacitor. The crystal oscillator 22 is connected to the circuit board 21
The end surface is pressed and held by the spring force of the bent portion 21e provided at the bridge 21f. Similarly, the temperature compensation capacitor 24 is connected to the bent portion 2.
It is held with a spring force of 1i. trimmer capacitor 2
8 is fixed with solder to the stepped portion 21h of the circuit base 21, which can also bend that part of the conductive sheet 25, and can be adjusted from the top side by removing the back cover. 2
1g is a coil connecting portion in which the conductive sheet 25 also has the same shape, and presses the coil terminal plate 20 made of an inelastic material with spring force. 25a is a + lead portion extending to the contact point 26 of the sheet 25, and 25c is a cable in which a conductive pattern of the conductive sheet 25 that does not fit within the plane of the circuit base 21 is provided along the side surface of the crystal resonator 22. Reference numeral 27 denotes a (-) spring of the battery 38, which is fixed by caulking the studs 27a to the circuit base 21. 21c is a mark carved into the circuit board 21. Utilizing the fact that the circuit board 21 is made of nickel silver, its surface is mirror-finished or has beautiful lines, while the surface of the main board 1 is As mentioned above, since it is spread flat and wide, if the surface of the main plate 1 is finished in the same manner, it can be made to have an extremely high-class feel in the movement state. The circuit base 21 is fixed to the base plate 1 with screws 21a or the like. screw 2
Counterbore processing such as 1a, mark engraving processing,
The material of the circuit base 21 is selected in terms of surface finish, strength as a base, spring function due to bending and planar shape, step formation by drawing and bending that can be freely designed at the height position of the mounted parts, component bonding strength, etc. The effect of using metal is great, and it can also be considered to be used as an electrostatic shield, a reinforcement function for the thin part of the main plate 1, the gear train bridge 2, the Hinoura wheel bridge 14, etc. The milling part 1j of the main plate 1, in which the circuit board 21 is accommodated, has thick parts 1e, 1 on the outer periphery of the main board in accordance with the recess of the circuit board 21.
f and 1g are left, and these contact the inner circumference of the case and have the function of determining the position of the movement in conjunction with other parts. For each 1g thick part,
Mechanical screws and dial screws are provided.

FIG. 2 is a sectional view taken along line A-A in FIG.
The winding stem 7 is loosely fitted into a horizontal hole in the main plate 1, and a stepped portion 7b formed at the raised portion of the tooth split cutter of the tooth portion 7a at the tip engages with the mandarin duck 8. This allows the diameter of the winding stem 7 to be reduced, making it possible to create a thin wristwatch.
By shortening the length of the watch, it is possible to make a small wristwatch. 7c
is a beveled portion at the leading edge of the winding stem 7, which allows the mandarin duck 8 to be pushed up when installing the winding stem 7. Although a large external force is applied to the winding stem 7 from the rear seat (not shown), the tip including the tapered step 7b that engages with the mandarin duck 8 is not loosely fitted into the main plate 1, etc., so that the step 7b is not loosely fitted. There is no risk of breakage, and the winding stem 7 can be designed to have a smaller diameter as described above. The crown gear part of the small iron wheel 11 meshes with the tooth part 7a of the winding stem 7, and since the mandarin pin 8 and the cannula 9 are integrated, they continue to mesh even when the winding stem 7 is pulled out or pushed in, and is switched. Prevents crushing of the teeth, which tends to occur during operation. The small iron car 11 is rotatably placed on the switching lever 10 by a seat 11a and a stud 11b so as to provide an appropriate axial clearance, and the intermediate car 12 is also placed on the switching lever 10 by a stud 12a.
Similarly, it is attached to the switching lever 10. The switching lever 10 is held on the base plate 1 with a stud 10a. The portion 11b' of the stud 11b of the small iron car 11 that protrudes from the switching lever 10 is provided with a reverse slope to prevent it from slipping out from the lattice 9b of the cannula 9. Therefore,
The tilting of the switching lever 10 in the upper surface direction (back cover direction) can be corrected by the lever 9, and disengagement of the tooth part 7a of the winding stem 7 and the small iron wheel 11 is prevented. From the right end of FIG. 2, the magnet 6a inserted into the hole of the stator 17,
A rotor 6 having a pinion 6c fixed thereto via a seat 6b made of nylon resin, and a fourth wheel & pinion 5, a third wheel & pinion 4, and a center wheel & pinion 3 of the reduction gear train are shown. The shaft support of the rotor 6 in the direction of the lower surface (direction of the dial) is a polyacetal resin bush 18b implanted in the stator plate 18. 1h is a hole for confirming the operation of the rotor 6, and 2 is a train wheel bridge near the dial 35. The center shaft 1a is installed perpendicularly to the plane of the main plate 1 with high precision so that the tilting of the center wheel 3 and hour wheel 16, that is, the deflection of the hour hand 33 and minute hand 34, is minimized.
3a is a washer that softens the friction between the hour wheel 16 and the center wheel 3, and 32 is a dial washer. The Hinoura holder 15 moves in three directions approximately equally spaced from its center of rotation.
The three protrusions 14a provided at 4 restrict the downward direction. 39 is the back cover, and 36 is the windshield. When the winding stem 7 is pulled out and rotated, the rotation is transmitted to the rotor 6, and a needle setting operation is performed.

FIG. 3 is a sectional view taken along line BB in FIG. A stator plate 1 that determines the plane position including the stator 17 by means of pins 1b planted in the main plate 1.
8 integrates the stator 17 with the extrusion part 17b,
The shaft portion 18a, which is screwed at the end, is connected to the stator 1.
It is pushed into hole 7. Winding core 19 of coil 19
Both bent ends of a are connected to the shaft portion 18a by countersunk screws 19.
It is closely coupled to the stator 17 by e. 19
d is the winding frame. A cross-sectional view perpendicular to the axial direction of the coil 19 shows the outer protective sheet 19b of the coil winding and its coupling surface 19b', and the silicone rubber 3
1. The coil holder 29, the shield plate 30, and their setscrews 29b are also shown. The right end in FIG. 3 is the terminal connection part of the coil 19, and the terminal plate 20 attached to the unbent protrusion 19a' of the coil winding core 19a, which is aligned with the main plate 1, is connected to the circuit board 21. The spring portion 21g presses the flexible conductive sheet 25 via the flexible conductive sheet 25. Note that the coil protection sheet 19b is a more stable and thin protection means than a heat-shrinkable tube or adhesive coating.

FIG. 4 is a sectional view taken along line CC in FIG. 1.
The drawn-out portion 25a of the conductive sheet 25 that has passed through the lower surface of the battery 38 is connected to a contact 26 fixed to the base plate 1 via an insulating bushing 26a with solder 26b. With the mandarin duck shaft 1c as the center of rotation, the back pusher 13
A contact spring 8c spot-welded to the mandarin duck 8 between the base plate 1 and the base plate 1 is in contact with the contact 26 under normal conditions. 35 is a dial plate, 35a is a dial foot, and 35b is a dial screw.

FIG. 5 is a sectional view taken along line D-D in FIG.
A cannula 9 for swinging the small iron car 11 and the like is fastened to the mandarin duck 8 with screws 9a. The portion 8d of the mandarin duck 8 that engages with the stepped portion 7b of the winding back 7 is cut into a semicircle to eliminate incomplete engagement between the winding stem 7 and the mandarin duck 8 as described above. This structure is based on the winding stem 7.
There is a drawback that the mandrel 8 is displaced in a direction perpendicular to the axis of the winding stem 7 when the mandrel shaft 1c is pulled out or pushed in.
is solved by making it an ellipse. 1k is mandarin duck 8
This is a hole into which a jig is inserted to push up the winding stem 7 and disengage it from the winding stem 7. The pin 8a installed in the mandarin duck 8 slides on the edges of the two holes 13a of the back presser 13 and performs a click operation when the winding stem 7 is pulled out or pushed in. 13b is a spring portion that presses the battery 38, and 13d is a set screw of the back presser 13. 38
A is a conductive rubber cushion that is placed on the caulked part of the lid of the battery 38 and absorbs the machining error of the caulked part, and the cross section is approximately triangular with the milling part of the main plate 1 in a space with no gap. Because of this, excessive compression will generate a strong repulsive force, and the dial 35 of the battery 38 will be generated when the watch is dropped.
This has the effect of extremely minimizing movement in this direction. The (-) spring 27, which is electrically connected to the cathode of the battery 38 and presses the battery 38 into the recess 39a of the back cover 39, has an insulating coating on its lower surface, and is attached to the circuit board 21 with studs 27.
It is fixed at a. 27b is solder which further increases this fixation and provides conduction, and 25a is a drawn-out portion of the conductive sheet 25 extending to the contact point 26.

FIG. 6 is a sectional view taken along line E-E in FIG.
The circuit base 21 has a shaped portion that matches the outer circumferential side of the battery 38, and the screw 2 that fits into the counterbore 21b is inserted near the portion.
1j to the main plate 1, and assists in positioning the battery 38. Temperature compensation capacitor 2
Reference numeral 4 indicates that conduction occurs at the folded portion 25b of the conductive sheet 25 supported by the two bent portions 21i of the circuit base 21, and an epoxy resin adhesive is used to supplement the holding function of the capacitor 24 due to the clamping force of that portion. There is 24a. The temperature compensation capacitor 24 made of barium titanate material changes its temperature characteristics even when heated with solder, but this structure does not have this problem, and it is possible to solder long lead material to the capacitor body in advance like in the past. There is a significant difference in time and space required for aging and mounting the capacitor on the board compared to soldering the ends of the lead material without applying heat to the capacitor body. In the center of FIG. 6, a bent conductive sheet cable portion 25c passing outside the crystal resonator 22 is shown, and its conductive pattern is coated with an insulating coating. A trimmer capacitor 28 is fixed by solder 28h to a drawn step 21h of the circuit base 21, which is fixed to the main plate 1 with screws 21k nearby. The trimmer substrate 28d and the trimmer rotor 28c made of dielectric material are connected to the upper and lower springs 28.
e, 28f, the shaft 28a and the stud 28b so as to generate an appropriate sliding torque. The upper spring 28e is fixed to the trimmer rotor 28c with solder 28g, and the trimmer rotor 28c can be rotated together from the direction of the back cover 39. The lower spring 28f comes into contact with the milled portion of the base plate 1, and receives the force directed toward the lower surface generated during the above-mentioned capacitor adjustment work. The position of the stepped portion 21h of the circuit base 21 is as follows:
It can be set according to the standard trimmer capacitor that you want to use commonly for various watches.

FIG. 7 is a sectional view taken along line FF in FIG.
The crystal oscillator 22, which is attached by absorbing the length error by the spring force of the bent portion 21e and the bridge portion 21f of the circuit base 21, is attached to the end of a tube 22b made of Kovar material with a lead sealed with glass 22c. Plate 22f and
A spring 22e fixed to the crystal resonator piece 22a with solder 22g is pressed into contact with a hole 22d' of a ceramic block 22d. 22
h is a vacuum sealing stopper made of metal, and it is also possible to change the structure to a structure in which a concave portion is provided and the structure is firmly fixed to the bent portion 21e. The lead plate 22f of the crystal resonator 22 is connected to the conductive sheet 25 with solder 22i. The right side of FIG. 7 shows an IC chip 23 mounted using a flip-chip method.
23a is an epoxy resin coating.

〔Effect of the invention〕

As described above, according to the present invention, even if a flexible circuit board is assembled into a watch by itself, it has no strength and will undulate, but by supporting this with a metal plate, a thin flexible circuit board can be used, and the watch can be made thinner. In addition, it becomes possible to reduce the cost of circuit blocks by producing hoops, which is possible with thin circuit boards.

Furthermore, when connecting circuit boards and electronic parts including the ground plate, it is extremely difficult to disassemble those joined by soldering, and in the case of connections between the ground plate and crystal resonator tubes, the soldering work itself is difficult. It becomes difficult. On the other hand, even when connecting with screws, there are disadvantages such as an increase in space and cost. There is no need for the contact part itself to have a separate elastic function to obtain contact pressure, the connection structure is simplified, and there is no need to place a connecting body between the contact part of the circuit board and the electrical contact part of the watch component. Since direct connection is possible, the planar and cross-sectional space is small, and this has a great effect on making watches thinner, smaller, and cheaper.

[Brief explanation of drawings]

FIG. 1 is a plan view of a crystal oscillation wristwatch according to an embodiment of the present invention, and FIGS. 2 to 7 are A-A, B-B, CC, D-D, and E- of FIG. 1, respectively. E,
A cross-sectional view along FF. 1...Main plate, 3...Second wheel, 4...Third wheel, 5
...Fourth wheel, 6...Rotor, 21...Circuit base,
35...Dial board, 39...Back cover.

Claims (1)

[Claims] 1. A base plate, a flexible circuit board on which a conductive pattern is formed on the surface facing the base plate and electronic components such as IC chips are connected and fixed thereon, and a flexible circuit board fixed to the base plate and having a size and shape that can cover most of the flexible circuit board. the flexible circuit board is interposed between the base plate and the elastic metal plate, and is in close contact with the elastic metal plate; A contact portion is provided, and a spring portion is formed on the elastic metal plate at a portion corresponding to the electric contact portion, and the elastic metal plate is connected to an inelastic electric contact portion of other watch parts such as a terminal plate of a coil arranged on the main plate. When the elastic metal plate is fixed to the base plate, the electric contact portion formed by the conductive pattern is directly pressed into contact with the elastic metal plate by the elastic pressing force of the spring portion of the elastic metal plate to establish electrical continuity. An electronic wristwatch featuring