JP2000065962A - Rotary weight, watch, and method for manufacturing oscillating weight - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently form parts in one piece with improved look even when an oscillating weight is formed in double-body structure with an oscillating weight body and a rotary heavy weight. SOLUTION: In the case of an oscillating weight 25 of an electronic clock hands type electronic watch, the outer-periphery part of an oscillating weight body 251 and a weight 252 are overlapped in the laser welding process for fixing the oscillating weight body 251 and the weight 252, and a laser beam is applied from the side of the rotary weight body 251 to the center of a recessed part 257 with a through hole 259 formed at the oscillating weight body 251. As a result, even if laser welding conditions are set weakly, the rotary weight body 251 and the weight 252 are securely welded by a laser beam around the bottom part of the through hole 259 out of the bottom part of the recessed part 257, thus preventing welding marks from remaining. Even if the welding marks remain, they are not prominent since they remain at the bottom part of the recessed part 257.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a oscillating weight, a mechanical or electronic timepiece using the oscillating weight, and a method of manufacturing the oscillating weight. More specifically, the present invention relates to a technique for fixing a rotating weight body and a rotating weight in a rotating weight.

[0002]

2. Description of the Related Art In a so-called electronic timepiece using a quartz oscillator or the like as a time reference, a small power generator 20 and a secondary power supply 30 constitute a power supply 10 as shown in FIG. As the step motor 40
Is to be driven. In the stepping motor 40, the timepiece train wheel 50 is connected to the motor rotor 42, and the hands attached to each wheel are driven. The small power generator 20 includes a rotating weight 25 that rotates by an external force, a power generating rotor 21 that rotates by a rotational driving force transmitted from the rotating weight 25, and a power generating rotor 21.
And a power generation coil 23 that forms a magnetic circuit with the power generation stator 22 and the power generation rotor 21, and accelerates the rotation of the rotary weight 25 with respect to the power generation rotor 21. A power train wheel 60 for transmitting the power is formed.

In some cases, the oscillating weight 25 used in such a small power generator 20 is formed as an integrally molded product by a method such as sintering. The portion to be the weight portion on the outer peripheral side is formed of the same material. However, if the oscillating weight 25 is formed of a material having a large specific gravity in order to increase the weight, the spring weight is lost on the rotation center side of the oscillating weight 25.
When an impact is applied to the weight of the weight 5, the rotation center of the rotary weight 25 may be broken. If the rotation center side of the oscillating weight 25 has no springiness, the impact applied to the weight portion of the oscillating weight 25 is directly transmitted to the inside of the electronic timepiece, and the power train 60 and the like may be damaged. .

Therefore, as shown in the example shown in FIG. 1, a portion corresponding to the center of rotation of the oscillating weight 25 is formed of a thin metal plate as an oscillating weight body 251 so as to have a spring property. The portion to be the weight portion is the rotating weight body 25
After forming the heavy rotating weight 252 with a metal having a large specific gravity different from that of the rotating weight 2, the outer peripheral portion of the rotating weight body 251 and the rotating weight 2 are formed.
52, and then, by caulking, resistance welding, or laser welding the overlapping portion, the rotating weight 251
And the weight 252 are being integrated. According to the rotating weight 25 having such a configuration, the rotating weight 2
52, even when an impact is applied to the rotating weight 2
Since the spring 51 relaxes and is absorbed, the rotating weight 251 is not damaged, and the shock applied to the rotating weight 252 is directly transmitted to the inside of the electronic timepiece to damage the power generation wheel train 60 and the like. Not even.

[0005]

However, when the oscillating weight 25 has a two-body structure of the oscillating weight body 251 and the oscillating weight 252, the following problems occur even when integrated using any of the fixing methods described above. There is a point. That is, since the swaged portion remains as it is when swaged and fixed, there is a problem that the appearance is poor. Further, in resistance welding, since the electrode contacts the welding location, deterioration (dirt and wear) of the electrode cannot be avoided. Therefore, the electrodes need to be frequently cleaned, and the working efficiency is low. In addition, in resistance welding, the contact state between the welding location and the electrode directly affects the welding strength, so that there is also a problem that the welding strength tends to vary. Furthermore, in laser welding, since the welding strength tends to decrease when the thickness of the member to be welded is large, the thickness of a metal plate generally used as the rotating weight 251 is:
Welding is performed under considerably stronger conditions. as a result,
A large welding mark remains on the oscillating weight 25, and there is a problem that the appearance tends to be poor, for example, the metal melted during welding scatters and adheres to the oscillating weight 25. However,
If the welding conditions are set weaker in laser welding, sufficient welding strength cannot be ensured.

Among these problems, the problem relating to poor appearance not only deteriorates the quality of the rotating weight 25 as a component, but also causes welding marks and the like on the electronic timepiece when the back cover is opened. , Or in an electronic timepiece whose back cover is made of a transparent material, the quality of the entire electronic timepiece is reduced.

[0007] In view of the above problems, an object of the present invention is to provide:
Manufacture of a oscillating weight, a timepiece and a oscillating weight using the oscillating weight that can efficiently and beautifully integrate these components even when the oscillating weight has a two-body structure of an oscillating weight and a oscillating weight. Is to implement the method.

[0008]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a thin rotating weight disposed on the rotation center side and an outer peripheral portion of the rotating weight overlap with each other. A thick rotary weight fixed to the rotary weight body, and a through hole is formed in the rotary weight body at the overlapping portion, and the rotary weight is formed in both openings of the through hole. The rotating weight body and the rotating weight are fixed by laser welding in a region centered on the opening on the side where the weight is located.

In the present invention, since laser welding is used, unlike resistance welding, cleaning of electrodes is not required.
Work efficiency is good. Also, when the laser beam is irradiated toward the through-hole, the laser beam directly reaches the bottom of the through-hole. The oscillating weight and the oscillating weight are sufficiently heated and melted. Therefore, even if the laser welding conditions are set to a relatively low value, the rotating weight body and the rotating weight can be properly welded, so that sufficient welding strength can be obtained. Therefore, since the laser welding condition can be set weakly, a large welding mark does not remain on the rotating weight body side. Even if welding marks remain, the welding marks are located at the bottom of the through-hole, so that the appearance does not deteriorate. Moreover, even if welding marks remain, they only remain in the through holes, so that the welding marks do not protrude from the surface of the rotating weight. Therefore, the protrusion caused by the welding mark does not hit the back cover or the like. Furthermore, since the portion where the through hole is formed is the scheduled welding position, the welding position is easy to understand,
Welding work becomes easy.

According to the second aspect of the present invention, the thick rotating weight fixed to the rotating weight at an overlapping portion of the thin rotating weight disposed on the rotation center side and the outer peripheral portion of the rotating weight. A weight, and the overlapping portion is formed in a concave portion on the outer surface of the both surfaces of the rotary weight body opposite to the side on which the rotary weight overlaps, and corresponds to a bottom portion of the concave portion The rotating weight body and the rotating weight are fixed in a region by laser welding.

In the present invention, since laser welding is used, unlike resistance welding, there is no need to clean the electrodes.
Work efficiency is good. In addition, since the laser welding portion is a concave portion, the thickness of this portion is thin, so even if the laser output is suppressed, the rotating weight body and the rotating weight are sufficiently heated at the bottom of the concave portion, Melts. Therefore, even if the laser welding conditions are set to a relatively low value, the rotating weight body and the rotating weight can be properly welded, so that sufficient welding strength can be obtained. Therefore, the laser welding conditions can be set weakly,
No large welding marks remain on the side of the oscillating weight. Also,
Even if welding marks remain, the welding marks remain at the bottom of the concave portion, so that the appearance does not deteriorate. Moreover, even if welding marks remain, they remain only in the recesses, so that the welding marks do not protrude from the surface of the rotating weight. Therefore, the protrusion due to the welding mark does not hit the back cover or the like. Furthermore, since the portion where the concave portion is formed is the welding scheduled position, the welding position is easy to understand,
Welding work becomes easy.

In the invention according to claim 3, in claim 2, the concave portion formed in the rotary weight body has a small diameter on the bottom side and a larger inner diameter on the outer surface side than the bottom side. It is characterized by having.

[0013] For example, in the invention according to claim 4, in claim 3, the inner peripheral surface of the concave portion formed in the oscillating weight body has a small diameter on the bottom side and a smaller diameter on the outer surface side than the bottom side. Is characterized in that it has a conical surface so as to open with a large inner diameter. With this configuration, there is an advantage that even if a welding mark remains in the concave portion, it is not conspicuous.

According to a fifth aspect of the present invention, in any one of the second to fourth aspects, the bottom of the recess formed in the oscillating weight has a through hole smaller than the inner diameter of the outer surface of the recess. It is characterized in that a hole is formed.
With this configuration, the laser beam directly reaches the bottom of the through hole at the bottom of the concave portion, so that the laser output is kept low, as in the case where the member to be welded is made thinner. The rotating weight is sufficiently heated and melted. Therefore, a sufficient welding strength can be obtained even if the laser welding conditions are set to be weaker. Therefore, since the laser welding conditions can be set weaker, no welding marks remain on the rotating weight body side.

According to a sixth aspect of the present invention, in the fifth aspect, the through hole is formed at the center of the bottom of the concave portion.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the overlapping portion of the rotating weight with the rotating weight body is located on the outer peripheral side of the overlapping portion in the rotating weight. It is characterized in that it is a step portion that is thinner than the thickness dimension of the portion to be formed. With this configuration, the weight of the rotating weight can be reduced in thickness even when the rotating weight and the rotating weight body are fixed at the overlapping portion.

For example, in the invention according to claim 8, in claim 7, the stepped portion of the rotary weight body is larger than a thickness dimension of a portion of the rotary weight located on an outer peripheral side of the overlapping portion. It is characterized by being thin by a thickness equivalent to the thickness dimension.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the rotating weight body is made of stainless steel, and the rotating weight is made of tungsten. When such a material is used, sufficient resilience can be imparted to the rotating weight body, and the rotating weight can be formed sufficiently heavy.

According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the laser-welded portion is formed at a plurality of locations along an overlapping portion between the rotary weight and the rotary weight. It is characterized by the following.

According to the eleventh aspect of the present invention, in any one of the first to ninth aspects, the laser welding portion is formed so as to be linearly connected along an overlapping portion between the rotating weight and the rotating weight. It is characterized by having been done.

According to a twelfth aspect of the present invention, there is provided a timepiece having a display mechanism for driving the oscillating weight defined in any one of the first to eleventh aspects with kinetic energy when the oscillating weight is rotated by an external force. It is characterized by being used for.

According to a thirteenth aspect of the present invention, there is provided a power generator for converting kinetic energy into electrical energy when the rotary weight is rotated, the power generator according to any one of the first to eleventh aspects, The present invention is characterized in that it is used for a clock having a secondary power supply for storing generated electric energy and a display device for performing timekeeping with the power supplied from the secondary power supply or the power generation device and displaying the timekeeping result. And

According to a fourteenth aspect of the present invention, in the twelfth or thirteenth aspect, the back cover of the timepiece case is arranged so as to cover the outer surface of the rotating weight body. Even when the back cover is arranged so as to cover the outer surface side of the oscillating weight body, the oscillating weight body and the oscillating weight are fixed to the outer surface of the oscillating weight body by welding in the oscillating weight to which the present invention is applied. Since the welding marks at the time are inconspicuous, even if the user opens the back cover, the appearance is good.

According to a fifteenth aspect of the present invention, in the fourteenth aspect, at least a portion of the back cover of the timepiece case that covers a laser welded portion between the rotating weight and the rotating weight body is transparent. I do. Even when such a transparent back cover is used, in the rotating weight to which the present invention is applied, welding marks when the rotating weight and the rotating weight are fixed to the outer surface of the rotating weight by welding are inconspicuous, We can provide high-quality watches.

According to a sixteenth aspect of the present invention, in manufacturing the oscillating weight defined in any one of the first to eleventh aspects, the laser welding step for fixing the oscillating weight body and the oscillating weight is performed by the laser welding step. After the outer peripheral portion of the oscillating weight and the oscillating weight are overlapped with each other, irradiation is performed by irradiating a laser beam from an outer surface of the both surfaces of the oscillating weight opposite to the side on which the oscillating weight overlaps. It is characterized by the following.

According to the seventeenth aspect of the present invention, in manufacturing the oscillating weight defined in the first aspect, a laser welding step for fixing the oscillating weight and the oscillating weight is performed by the laser welding step. After stacking the outer peripheral part and the rotating weight,
The method is characterized in that the laser beam irradiation is performed from the outer surface of the both surfaces of the oscillating weight body opposite to the side on which the oscillating weights overlap with each other toward the through hole.

According to the eighteenth aspect of the present invention, in manufacturing the oscillating weight defined in the second aspect, the laser welding step for fixing the oscillating weight and the oscillating weight is performed by the laser welding step. After stacking the outer peripheral part and the rotating weight,
The method is characterized in that the laser beam irradiation is performed from the outer surface of the both surfaces of the oscillating weight body opposite to the side on which the oscillating weight is overlapped toward the bottom of the concave portion.

In the invention according to claim 19, in manufacturing the oscillating weight defined in claim 6, the laser welding step for fixing the oscillating weight and the oscillating weight is performed by the laser welding step. After stacking the outer peripheral part and the rotating weight,
It is performed by irradiating a laser beam from the side of the outer surface opposite to the side on which the rotating weight overlaps with the rotating weight to the through hole formed at the bottom of the concave portion of the both surfaces of the rotating weight body. Features.

[0029]

Embodiments of the present invention will be described with reference to the accompanying drawings.

(Overall Configuration) In FIG. 1, a pointer-type electronic timepiece 1 of the present embodiment is an analog crystal wristwatch of a pointer display type, and is based on a signal transmitted from a crystal oscillator 32 mounted on a circuit board 31. The step motor 40 is driven. The step motor 40 is formed by winding a motor rotor 42 made of a permanent magnet magnetized to two poles, a motor stator 43 having a cylindrical rotor arrangement hole 430 in which the motor rotor 42 is arranged, and a coil 41. And a coil block comprising the magnetic core 44.
The third wheel & pinion 5 is connected to the motor rotor 42 via a kana portion.
3, a timepiece train wheel 50 including a second wheel 54, a minute wheel 55, and an hour wheel 56 is connected. A minute hand 69 is fixed to the shaft end of the center wheel & pinion 54, and an hour hand 6 is attached to the tip of the cylindrical shaft of the hour wheel 56.
3 is fixed. In this way, a display device (movement) for performing timekeeping and displaying the timekeeping result is configured, and the display device includes a power supply unit 1 described below.
It is driven by power supply from 0.

The power supply unit 10 for driving the step motor 40 is generally constituted by a small power generator 20 and a secondary power supply 30 (capacitor). Small power generator 2
Numeral 0 denotes a single-piece rotating weight 25 which is rotated by an external force, such as when an arm on which the pointer-type electronic timepiece 1 is fitted is moved, a power-generating rotor 21 which rotates by receiving kinetic energy from the rotating weight 25, A power generation stator 22 sandwiching the power generation rotor 21 and a power generation coil 23 constituting a magnetic circuit with the power generation stator 22 and the power generation rotor 21.

The rotary weight 25 and the power generation rotor 21 are mechanically connected by a power generation wheel train 60 that transmits the rotational operation of the rotary weight 25 at an increased speed.
It is composed of a rotary wheel 61 integrally formed with the rotary weight 25 and a power generation rotor transmission wheel 62 having a pinion engaged with the gear. The power generation rotor 21 has magnetic poles N and S
Are formed, and when the rotation of the rotary weight 25 is transmitted, the magnetic poles N and S rotate.
3, an induced electromotive force can be obtained, and the secondary power supply 30 can be charged. As will be described in detail later, the rotary weight 25 is provided with a rotary weight fixing screw 261 at the center of rotation.

(Structure of oscillating weight)
In order to prevent the shock applied to the outer peripheral side from damaging the center side of the rotary weight 25, and to prevent the shock applied to the outer peripheral side from being directly transmitted to the movement in the timepiece and damaging the movement. It has a shock absorbing structure.

In this embodiment, as shown in FIG. 2 (A) and FIG. 2 (B), as an enlarged view of the oscillating weight 25, the oscillating weight 25 is provided on the rotation center side of the oscillating weight 25. A thin oscillating weight 251 arranged, and the oscillating weight 251
Of the thick rotating weight 252 fixed to the rotating weight body 251 by laser welding at the overlapping portion 250 with the outer peripheral portion of
For example, the thickness of the rotating weight body 251 is set to 0.35 so that sufficient resilience can be obtained.
mm of stainless steel. The rotating weight 252 is formed of a 0.85 mm thick molded product made of tungsten so as to have a sufficient weight.
If such a oscillating weight 25 is used, the impact applied to the oscillating weight 252 is reduced by the spring property of the oscillating weight 251.
Since it is absorbed, it is possible to prevent the mechanical part of the center of the rotating weight 25 or the inside of the timepiece from being damaged by the impact applied to the rotating weight 252, and to increase the unbalance amount of the weight of the rotating weight 25. is there. Further, a groove-shaped opening 262 is formed in the oscillating weight 251 so that the oscillating weight 251 is easily bent, and the impact applied to the oscillating weight 252 is reliably reduced and absorbed.

Here, the oscillating weight body 252 of the oscillating weight 251
In the overlapping portion 250, the step portion 25 which is thinner by a thickness t2 equivalent to the thickness dimension of the rotary weight body 251 than the thickness dimension t1 of the portion located on the outer peripheral side of the overlapping portion 250.
It is 3. Therefore, the rotating weight 25 is
Even with a structure in which the weight 2 and the oscillating weight 251 are fixed at the overlapping portion 250, the oscillating weight 25 can be made thin.

In such a two-body rotating weight 25, conventionally, when the rotating weight body 251 and the rotating weight 252 formed separately are fixed, there is a problem in terms of work efficiency and poor appearance. However, in the present embodiment, such a problem is solved by employing the configuration described below.

(First Example of Fixed Structure of Rotating Weight 251 and Rotating Weight 252) FIGS. 3A and 3B respectively show the rotating weight 251 and the rotating weight 252 of the rotating weight 25 of this embodiment.
FIG. 2 is a plan view of a rotary weight 25 showing a welding structure of FIG. 1 and an enlarged sectional view of a welding portion L1 (a shaded region).

As shown in FIGS. 3A and 3B, in the rotary weight 25 according to the present embodiment, at the overlapping portion 250 between the outer peripheral portion of the rotary weight 251 and the rotary weight 252, the rotary weight 2
51, a through hole 255 having an inner diameter of about 0.3 mm is formed. Of both openings of the through hole 255, a rotary weight 252 is formed.
In the region centered on the opening on the side where
And the rotary weight 252 are laser-welded. here,
The laser welding portion L1 is formed at a plurality of locations along the overlapping portion 250.

When manufacturing the rotary weight 25 having such a configuration, in the laser welding step for fixing the rotary weight 251 and the rotary weight 252, the outer peripheral portion of the rotary weight 251 and the rotary weight 252 are formed. Are overlapped with each other, and a through hole 255 having an inner diameter of about 0.3 mm is formed from the outer surface of the rotating weight 251 opposite to the side on which the rotating weight 252 overlaps.
Is irradiated with a laser beam (YAG laser).
Here, the spot diameter of the laser beam is 0.4 mm to 0.2 mm.
6 mm, which is larger than the inner diameter of the through hole 255. As a result, at the bottom of the through hole 255, the oscillating weight 251 and the oscillating weight 252 are heated and melted, and the oscillating weight 25
1 and the rotary weight 252 are integrated by laser welding.

According to such a method, the working efficiency is good, for example, unlike the resistance welding, the electrode does not need to be cleaned. In addition, since the laser beam directly reaches the bottom of the through hole 255, even if the laser output is suppressed to a low level as in the case where the member to be welded is made thinner, the rotating weight 251 and the rotating weight are kept at the bottom of the through hole 255. The weight 252 is sufficiently heated and melted. As described above, even if the laser welding conditions are set to be relatively low, the rotating weight body 25 is formed at the bottom of the through hole 255.
1 and the rotating weight 252 can be appropriately welded, so that sufficient welding strength can be obtained. Therefore, since the laser welding conditions can be set weaker, large welding marks do not remain on the outer surface side of the rotating weight 251, and even if welding marks remain, the welding marks are located at the bottom of the through hole 255. , It does not result in poor appearance. Therefore, as will be described later, even if the back cover of the watch case arranged so as to cover the outer surface side of the oscillating weight 251 is transparent, the quality of the watch is not degraded by welding marks. Further, even if welding marks remain, only the welding marks remain in the through holes 255, so that the welding marks protrude from the surface of the rotary weight 25 and
There is no hindrance to rotation. Furthermore, the through hole 25
Since the portion where 5 is formed is the scheduled welding position, the welding position is easy to understand, so that the welding operation is facilitated.

(Second Example of Fixed Structure of Rotating Weight 251 and Rotating Weight 252) FIGS. 4A and 4B respectively show the rotating weight 251 and the rotating weight 252 of the rotating weight 25 of the present example.
Plan view of a rotary weight showing a welding structure with
FIG. 2 is an enlarged sectional view of 1 (a hatched area).

As shown in FIGS. 4A and 4B, in the rotary weight 25 of the present embodiment, at the overlapping portion 250 between the outer peripheral portion of the rotary weight 251 and the rotary weight 252, the rotary weight 251 is formed.
Of the two surfaces, the outer surface opposite to the side on which the rotating weight 252 overlaps has a depth of 0.10 mm and an inner diameter of 1.3 mm to
A 1.5 mm concave portion 256 is formed, and the rotary weight body 251 and the rotary weight 252 are laser-welded in a region corresponding to the bottom of the concave portion 256 (the hatched region indicates the laser welded portion L
1) is fixed.

In manufacturing the rotary weight 25 having such a configuration, in the laser welding process for fixing the rotary weight 251 and the rotary weight 252, the outer peripheral portion of the rotary weight 251 and the rotary weight 252 are formed. Then, a laser beam (YAG laser) is irradiated from the outer surface of the both surfaces of the oscillating weight 251 opposite to the side where the oscillating weight 252 overlaps toward the center of the concave portion 256. Here, the spot diameter of the laser beam is 0.4 mm to 0.6 mm,
Since the laser beam is smaller than the inner diameter of
6. Only the bottom of 6 is irradiated. As a result, the rotating weight 251 and the rotating weight 252 are heated and melted at the bottom of the concave portion 256.

According to such a method, the thickness of this portion is set to 0.2 because the portion irradiated with the laser is the concave portion 256.
Since the thickness is as thin as 5 mm, the rotating weight 251 and the rotating weight 252 are sufficiently heated and melted at the bottom of the concave portion 256 even if the laser output is suppressed low. As described above, even if the laser welding conditions are set to be relatively low, the rotating weight body 251 and the rotating weight 252 can be properly welded at the bottom of the concave portion 256, and thus sufficient welding strength can be obtained. Therefore, since the laser welding conditions can be set weaker, a large welding mark does not remain on the outer surface side of the rotating weight 251 and even if the welding mark remains, the welding mark remains in the recess 2.
Since it only remains at the bottom of 56, the appearance does not deteriorate. Therefore, as will be described later, even if the back cover of the watch case arranged so as to cover the outer surface side of the oscillating weight 251 is transparent, the quality of the watch is not degraded by welding marks. Also, even if welding marks remain, the concave portions 256
Therefore, the welding marks do not protrude from the surface of the oscillating weight 25 and hinder the rotation of the oscillating weight 25. Further, since the portion where the concave portion 256 is formed is the welding expected position, the welding position is easy to understand, so that the welding operation is facilitated.

(Third Example of Fixed Structure of Rotating Weight 251 and Rotating Weight 252) FIGS. 5A and 5B respectively show the rotating weight 251 and the rotating weight 252 of the rotating weight 25 of the present example.
FIG. 2 is a plan view of a rotary weight 25 showing a welding structure of FIG. 1 and an enlarged sectional view of a welding portion L1 (a shaded region).

As shown in FIGS. 5 (A) and 5 (B), also in the rotary weight 25 of this embodiment, the rotary weight 251 is formed at the overlapping portion 250 between the outer peripheral portion of the rotary weight 251 and the rotary weight 252.
A concave portion 257 is formed on an outer surface of the opposite surface of the both surfaces of the rotary weight 252 on the side opposite to the side where the rotary weight 252 overlaps, and in a region corresponding to the bottom of the concave portion 257, the rotary weight body 251 and the rotary weight 2
52 and laser welding (shaded area is laser welded portion L1)
It is fixed by. Here, the inner peripheral surface 258 of the concave portion 257 formed in the oscillating weight 251 has a small inner diameter of 0.02 mm on the bottom side and a larger inner diameter on the outer surface side (for example, an inner diameter of 1.20 mm) than the bottom side. ) So as to open with a diagonal upward conical surface. Further, in the center position of the bottom of the concave portion 257 formed in the oscillating weight 251, a through hole considerably smaller than the inner diameter of the outer surface side of the concave portion 257, for example, the inner diameter is 0.20 mm
Are formed.

In manufacturing the rotary weight 25 having such a configuration, in the laser welding process for fixing the rotary weight 251 and the rotary weight 252, the outer peripheral portion of the rotary weight 251 and the rotary weight 252 are formed. After that, the laser beam (YAG laser) is irradiated from the outer surface of the both surfaces of the oscillating weight body 251 opposite to the side on which the oscillating weight 252 overlaps toward the center of the concave portion 257. Here, the spot diameter of the laser beam is 0.4 mm to 0.6 mm,
Since the diameter of the opening is smaller than that of the opening 57, the laser beam
Irradiation is performed only in the inside 57. As a result, the rotating weight 251 and the rotating weight 252 are heated, melted, and welded at the bottom of the concave portion 257. Moreover, since a small through hole 259 is formed at the center of the bottom of the concave portion 257, the rotating weight body 251 and the rotating weight 252 are particularly formed at the bottom of the concave portion 257, particularly at the bottom of the through hole 259. It is heated, melted and welded.

According to such a method, the rotating weight body 251 and the rotating weight 252 are sufficiently heated at the bottom of the recess 257 even if the laser output is suppressed to the extent that the laser irradiation position is the recess 257. Is melted. Moreover,
Since the laser beam directly reaches the bottom of the through hole 259 at the bottom of the recess 257, even if the laser output is suppressed to a considerably low level, as in the case where the member to be welded is made thinner, the rotating weight body is formed 251 and rotating weight 252 are sufficiently heated and melted. Therefore, even if the laser welding conditions are set to be relatively low, the rotating weight body 251 and the rotating weight 252 can be properly welded, so that sufficient welding strength can be obtained. Therefore, a large welding mark does not remain on the rotating weight 251 side. Further, even if welding marks remain, the welding marks remain on the bottom of the concave portion 257, so that the appearance does not deteriorate. In addition, even if welding marks remain, the inner peripheral surface of the concave portion 257 has a slanting upward conical surface, so that the welding marks remain to fill the bottom of the concave portion 257 and are indistinguishable from the welding marks. . Therefore, as will be described later, even if the back cover of the watch case arranged so as to cover the outer surface side of the oscillating weight 251 is transparent, the quality of the watch is not degraded by welding marks. Further, even if a welding mark remains, the welding mark remains only in the concave portion 257, so that the welding mark does not protrude from the surface of the rotary weight 25. Furthermore, since the portion where the concave portion 257 is formed is the welding scheduled position, the welding position is easy to understand, and the welding operation is facilitated.

(Other Examples of Fixed Structure of Rotating Weight 251 and Rotating Weight 252) FIGS. 6 (A) and 6 (B)
It is a top view of the oscillating weight 25 which concerns on the other example of this invention.

In the welding structure described with reference to FIGS. 3 to 5, the laser welding portion L1 is provided at a plurality of positions, for example, at positions separated from each other along the overlapping portion 250 of the rotating weight body 251 and the rotating weight 252. Although the example is formed at three places, as shown in FIGS. 6A and 6B, the laser welding portion L1 is linear along the overlapping portion 250 of the rotating weight body 251 and the rotating weight 252. Seam welding may be performed so as to be connected in a shape.

Of these examples, the structure shown in FIG. 6A corresponds to a modification of the structure described with reference to FIG. 3, and is formed along the overlapping portion 250 of the oscillating weight 251 and the oscillating weight 252. The laser welded portion L1 is connected linearly, and the through hole 255 of the structure described with reference to FIG. 3 has a planar structure that extends linearly long along the overlapping portion 250.

The structure shown in FIG. 6B corresponds to a modification of the structure described with reference to FIGS. 4 and 5, and is shown along the overlapping portion 250 of the oscillating weight 251 and the oscillating weight 252. The laser welding portion L1 is connected linearly, and the concave portion 25 having the structure described with reference to FIGS.
6 or a concave portion 257 having a through hole 259 also has a linearly elongated planar structure.

(Fixed Structure of Rotating Weight and Wheel Train) The arrangement structure of each component having a power generation function and a hand movement function in a pointer-type electronic timepiece incorporating the small-sized power generation device thus configured will be described.

FIG. 7 shows a main plate 2, a first train wheel bridge 3, and a second wheel supporting each component in the pointer-type electronic timepiece of this embodiment.
FIG. 2 is a plan view showing a layout of a train wheel bridge 6 of the base plate 2,
The outlines of the first train wheel bridge 3 and the second train wheel bridge 6 are indicated by a thick solid line, a thick dotted line, and a thick one-dot chain line, and other parts are indicated by thin lines.

In FIG. 7, the central portion of the main plate 2 is a portion to be the center of rotation of the rotary weight 25 and each pointer. The base plate 2 is provided with a timepiece dial on the back side, and in the drawing, in each angular direction of the base plate 2, each time (3 o'clock, 6 o'clock, 9 o'clock, 12 o'clock). The rotation area of the oscillating weight 25 is an area indicated by a dashed line L1 slightly inside the outer peripheral edge of the main plate 2. Inside the one-dot chain line L1, the one-dot chain line L2 indicates the rotational position of the boundary between the oscillating weight body 251 (thin portion) and the oscillating weight 252 (thick portion), which are formed on the oscillating weight 25. .

(Arrangement of timepiece train wheel) FIG. 8 is a view showing the minute wheel 55, the center of the rotating weight 25 (the screw 251 for fixing the rotating weight), the second wheel 54, the hour wheel 56, and the third wheel in FIG. It is sectional drawing when it cut | disconnects in the position which passes the wheel 53, the motor rotor 42, and the set screw 26.

As shown in FIG. 7 and FIG.
Area (rotational area of the oscillating weight 251)
The third wheel 53 and the second wheel 5 described with reference to FIG.
4. A train wheel train 50 having a large height such as a minute wheel 55 and an hour wheel 56 is arranged. The third wheel 53, the minute wheel 55, and the motor rotor 42 of the timepiece wheel train 50 are composed of the main plate 2 and the first flat wheel train receiver 3 which is disposed to face the main plate 2. Is supported via a tenon frame made of a pit stone S or the like. The first train wheel bridge 3 is entirely disposed inside the rotation region of the thin portion 251 of the oscillating weight 25, that is, inside the dashed line L2.

Here, the arrangement of the timepiece wheel train 50 and its surroundings will be described in detail. In the plane direction of the movement, a center wheel & pinion 54 supporting a minute hand 69 at the center thereof.
Is arranged. In the thickness direction, in the direction from the gear portion of the second wheel & pinion 54 to the rotary weight 25, the pinion of the second wheel & pinion 54, the third wheel & pinion 53, and the second wheel & pinion 5 supported by the second wheel train bearing 6
The upper tenon bearing portion 4, the bearing shaft 97 fixed to the first train wheel bearing 3, the ball bearing 90, and the rotary weight fixing screw 261 are arranged in this order, and the thickness of the movement is determined at this portion.

The third wheel & pinion 53, the minute wheel & pinion 55 and the motor rotor 42 are supported between the first train wheel bridge 3 and the main plate 2, and the second wheel train bridge 6 and the main plate 2 are connected to each other. In comparison with the parts supported between the two, the upper tenon (the tenon on the first wheel train 3 side) and the lower tenon (the tenon on the main plate 2 side) ) Can be made longer. Therefore, with respect to the third wheel & pinion 53, the minute wheel & pinion 55 and the motor rotor 42, the inclination of these wheel trains can be reduced even if the upper and lower bearings are slightly displaced in plane.

Here, the first train wheel bridge 3 is fixed to the base plate 2 together with the second train wheel bridge 6 by three setscrews 17, 18, 26. 251 is located inside the rotation area. Fixing using such a screw is excellent in reliability when used for a long time or when repeatedly attached and detached, and can be made inexpensive because of its simple structure. Further, as can be seen from FIG. 7, the timepiece train wheel 5 is placed in a region which is planarly surrounded by the screwing points by the three setscrews 17, 18 and 26.
0 (the third wheel 53, the second wheel 54, the minute wheel 55, and the hour wheel 56) are located. Further, the first train wheel bridge 3 is arranged in a range overlapping with all of the power generation wheel train 60 and the timepiece wheel train 50, but the second wheel train bridge 6 has three setscrews 17 and 18. , 26 are fixed to the base plate 2 together with the first train wheel bridge 3 by the set screws 17, 18, and do not overlap with the power generation rotor 21 and the power generation rotor transmission wheel 62 of the power train 60, and It is arranged so as to substantially overlap with the row 50. Such set screws 17, 18, 26
The area surrounded by the screwing points by
When it is attempted to deform to the side of the timepiece train wheel 50, since it is reinforced by the second wheel train bearing 6, it has a large strength. The center wheel 53, the center wheel 54, the minute wheel 55, and the hour wheel 56) can be supported. Moreover, the set screws 17, 18, and 26 for fixing the first train wheel bridge 3 to the base plate 2
Are disposed so as to surround the rotary weight fixing screw 261 attached to the train wheel bridge 3. For this reason, the rotating weight 25
Therefore, even if an external force acts on the first train wheel bridge 3, the part of the set screw for fixing this wheel train bridge supports near the center.
The wheel train receiver 3 is hardly bent, and the wheel train can be reliably supported.
Further, since the fixed portion of the oscillating weight 25 is stabilized,
5 can also be suppressed.

(Rotating Weight Support Structure) As can be seen from FIG. 8, the rotating weight 25 is mounted on the first train wheel bridge 3 via the ball bearing 90. The ball bearing 90 is
Inner member 9 supporting bearing ball 91 on the inner peripheral side
2, and an outer ring 93 (outer member) for holding a plurality of bearing balls 91 between the inner member 92 and the inner member 92. The inner member 92 includes an inner ring 94 having an L-shaped cross section in which a flange portion projects outward from a cylindrical portion, a ball pressing ring 95 which is press-fitted into the inner ring 94 and forms a ball raceway surface together with the inner ring 94, and a bearing ball. And a retainer 96 for defining the position of 91.

As described below, the inner race 94 is fixed to the first train wheel bridge 3 via a bearing shaft 97 (guide shaft). First, the first train wheel bridge 3 has a stepped receiving hole 3
01 is formed therein, and the bearing shaft 97 is mounted so that the tip end protrudes. A flange 971 larger than the receiving hole 301 is formed at the base of the bearing shaft 97, and the flange 971 is hooked on a step of the receiving hole 301. The inner ring 94 is fitted to the shaft portion of the bearing shaft 97 in this state, and the rotary weight fixing screw 261 is fixed to the female screw formed on the distal end surface of the bearing shaft 97. In this state, the rotating weight fixing screw 261 raises the bearing shaft 97 so that the head has the inner ring 94 and the ball pressing ring 95.
Is pressed toward the first train wheel bridge 3, so that the inner ring 94 and the ball holding ring 95 are tightened and fixed to the first train wheel bridge 3 by the rotary weight fixing screw 261. As a result, the ball bearing 90 is positioned in the plane direction by the center hole of the inner ring 94 and the bearing shaft 97, and the height position is defined by tightening with the rotary weight fixing screw 261.

(Ball Bearing Fixing Structure) In this embodiment, among the components of the ball bearing 90, the inner member 92 to which the rotary weight fixing screw 261 is fixed is the first wheel train bearing 3 which is a fixed-side member. , And the rotary weight 25 is fixed to the outer ring 93. For this reason, the mounting portion of the screw 261 for fixing the oscillating weight is fixed to the last, and does not rotate, so that the screw 261 for fixing the oscillating weight can be used even if it is subjected to long-term carrying, strong impact, or repeated repeated light impacts. 261 does not loosen. Therefore, the rotary weight fixing screw 2
There is no problem such as breakage of the ball bearing 90 caused by the loosening of the ball bearing 61.

FIG. 9 shows the arrangement of the power generation coil 23, the power generation rotor 21, the power generation rotor transmission wheel 62, the minute wheel 55, and the center of the rotation weight 25 (rotational weight 25) in FIG. It is sectional drawing when it cut | disconnects in the position which passes through the center wheel & pinion 54 and the hour wheel 56.

As shown in FIG. 7 and FIG.
The small power generator 20 is configured in a region from the rotation region of the rotary weight body 251 (thin portion) to the rotation region of the rotary weight 252 (thick portion). As can be seen from FIG. 9, in the small power generator 20, the power generation rotor 21
The power transmission rotor transmission wheel 62 meshes with the pinion 210, and the power transmission rotor transmission wheel 62 has a pinion 620
A rotary wheel 61 that rotates together with the rotary weight 25 meshes. Here, not only the oscillating wheel 61 but also the power generation rotor transmission wheel 62 has a large height, so that the oscillating weight 2
51 (thin portion) is arranged in the rotation area.

(Structure of Impact of Rotating Weight) In the rotating weight 25, the rotating weight body 251 is provided with an impact reducing function, so that the outer peripheral portion of the rotating weight 25 rotates while moving up and down. In this embodiment, a middle frame 5 (fixed frame) is used as a structure for receiving such a vertical movement. That is, the movement configured on the main plate 2 is housed between the back cover 68 sandwiching the middle frame 5 on the outer peripheral side thereof and the case 78 of the watch case. In this state, the middle frame 5 has reached a position overlapping the outer peripheral portion of the rotary weight 25. In the present embodiment, a dowel 502 protruding toward the oscillating weight 25 is formed on an end face of the portion 501 near the inner periphery of the middle frame 5 that faces the oscillating weight 25. By setting the dowel 502 at a height position closer to the rotary weight 25 in the thickness direction than the components around the dowel, when the rotary weight 25 rotates while moving up and down, the rotary weight 2
5 strikes the dowel 502 of the middle frame 5 first, and its posture is corrected, so that components around the dowel can be prevented from breaking due to contact with the rotary weight 25. Also, dove 5
02 are formed at equal angular intervals, so that the weight 2
When the rotating body 5 rotates while moving up and down, the rotating weight 25 alternately hits some of the dowels 50 of the middle frame 5 and its posture is corrected, so that the entire movement is damaged by the contact of the rotating weight 25. This can be prevented.

Here, in the watch case that houses the pointer-type movement (display device), the secondary power supply 30, and the power generator 20, the back cover 68 is arranged so as to cover the outer surface side of the oscillating weight 251. The back cover 68 is entirely transparent. Nevertheless, in the present embodiment, the oscillating weight 251, the oscillating weight 2
Since the welding mark when fixing 52 with welding is inconspicuous, a high-quality timepiece can be provided.

The user may open the back cover even if the back cover 68 is not transparent.
In 5, welding marks when the rotating weight 251 and the rotating weight 252 are fixed by welding are not conspicuous on the outer surface of the rotating weight 251, so that a high-quality timepiece can be provided.

(Example of Use in Mechanical Watch) In the above embodiment, an example was described in which the oscillating weight according to the present invention was used in a power generating device of an electronic timepiece. For example, the present invention may be applied to a mechanical timepiece that drives a pointer-type display mechanism with the energy stored here.

[0070]

As described above, in the oscillating weight, the timepiece and the method of manufacturing the oscillating weight according to the present invention, the oscillating weight and the oscillating weight are fixed by laser welding when the oscillating weight is manufactured. Work efficiency is good, such as no need to clean the electrodes. In addition, since the laser welding is performed at the bottom of the through hole or the concave portion, similarly to the case where the member to be welded is thinned, even if the laser output is suppressed to a low level, the rotating weight and the rotating weight are sufficiently at the bottom of the through hole or the concave portion. Heats and melts. Therefore, sufficient welding strength can be obtained even if the laser welding conditions are set to be relatively low. Therefore,
Because the laser welding conditions can be set weakly, no large welding marks remain on the side of the rotating weight body, and even if welding marks remain, the welding marks are located at the bottom of the through hole or concave part. There is no failure. Therefore, even if the electronic timepiece is configured by covering the transparent back cover so as to cover the rotating weight, welding marks do not reach the user's eyes. Also, even if welding marks remain, the welding marks only remain in the through-holes or recesses and do not protrude from the surface of the rotating weight, so that the protrusion caused by the welding marks does not hit the back cover or the like. . Further, since the portion where the through-hole is formed is the scheduled welding position, the welding position is easily understood, and the welding operation is facilitated.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing the entire configuration of a pointer-type electronic timepiece.

FIGS. 2A and 2B are a plan view of a oscillating weight used in a power generator of a pointer-type electronic timepiece to which the present invention is applied, and oscillating weights and oscillating weights constituting the oscillating weight; FIG. 4 is an enlarged cross-sectional view around the fixed portion of FIG.

FIGS. 3A and 3B are a plan view of a rotary weight used in a power generator of a pointer-type electronic timepiece to which the present invention is applied, and welding of the rotary weight and the rotary weight in the rotary weight. It is an expanded sectional view of a part periphery.

FIGS. 4A and 4B are plan views of another rotary weight used in a power generator of a pointer-type electronic timepiece to which the present invention is applied, and a rotary weight, a rotary weight and a rotary weight of the rotary weight. FIG. 4 is an enlarged sectional view of the vicinity of a welded portion of FIG.

FIGS. 5A and 5B are a plan view of still another rotating weight used in a power generator of a pointer-type electronic timepiece to which the present invention is applied, and a rotating weight and a rotating weight of the rotating weight. It is an expanded sectional view of the periphery of the welding part.

FIGS. 6A and 6B are plan views of another rotating weight used in a power generator of a pointer-type electronic timepiece to which the present invention is applied.

FIG. 7 is a plan view showing a layout of a main plate, first train wheel bridge, and second train wheel bridge supporting each component in the pointer-type electronic timepiece to which the embodiment is applied.

FIG. 8 shows a minute hand, a center of a rotating weight (a screw for fixing a rotating weight), a second wheel,
It is sectional drawing when it cut | disconnects in the position which passes through an hour wheel, a 3rd wheel, a motor rotor, and a set screw.

FIG. 9 shows a pointer-type electronic timepiece to which the present invention is applied, a power generating coil, a power generating rotor, a power generating rotor transmission wheel, a minute wheel, a center of a rotating weight (a rotating weight fixing screw), a second wheel, It is sectional drawing when it cut | disconnects in the position which passes an hour wheel.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pointer-type electronic timepiece 2 main plate 3 first train wheel receiver 5 middle frame 6 second wheel train receiver 7 crown 10 power supply unit 17, 18, 26 set screw 20 small power generator 21 power generation rotor 22 power generation stator 23 power generation Coil 25 Rotating weight 30 Secondary power supply (capacitor) 31 Circuit board 32 Crystal oscillator 40 Step motor 41 Coil 42 Motor rotor 43 Motor stator 44 Magnetic core 52 Fourth wheel 53 Third wheel 54 Second wheel 55 Back of day Car 56 hour wheel 50 clock train wheel 60 power train wheel 61 oscillating weight wheel 62 power generation rotor transmission wheel 63 hour hand 64 second hand 68 back cover 69 minute hand 250 overlapped portion of oscillating weight and rotating weight 251 rotation made of thin plate Weight (thin portion) 252 Rotating weight (thick portion) 255, 259 Through hole 256, 257 Concave L1 Laser welded portion

Claims (19)

[Claims] A thin rotating weight disposed on a rotation center side, and a thick rotating weight fixed to the rotating weight at an overlapping portion of an outer peripheral portion of the rotating weight; In the overlapping portion, a through hole is formed in the oscillating weight, and the oscillating weight and the oscillating weight are formed in a region centered on an opening on the side where the oscillating weight is located, of both openings of the through hole. A rotary weight, wherein the rotary weight is fixed by laser welding. 2. A thin rotary weight disposed on the rotation center side, and a thick rotary weight fixed to the rotary weight at an overlapping portion of an outer peripheral portion of the rotary weight, In the overlapping portion, a concave portion is formed on the outer surface of the both surfaces of the rotary weight body opposite to the side on which the rotary weight overlaps, and the rotary weight body is formed in a region corresponding to the bottom of the concave portion. And the rotating weight is fixed by laser welding. 3. The recess according to claim 2, wherein the concave portion formed in the oscillating weight body has a small diameter on the bottom side and has an inner diameter larger on the outer surface side than the bottom side. Oscillating weight. 4. The inner peripheral surface of the concave portion formed in the rotating weight body according to claim 3, wherein a bottom side has a small diameter, and the outer surface side has an inner diameter larger than that of the bottom side. A rotary weight characterized by having a conical surface. 5. The method according to claim 2, wherein
A rotary weight, wherein a through hole smaller than an inner diameter of an outer surface of the concave portion is formed in a bottom of the concave portion formed in the rotary weight body. 6. The rotary weight according to claim 5, wherein the through hole is formed at the center of the bottom of the recess. 7. The method according to claim 1, wherein
An overlapping portion of the rotating weight with the rotating weight body is a step portion which is thinner than a thickness dimension of a portion of the rotating weight located on an outer peripheral side of the overlapping portion. Rotating weight. 8. The rotary weight according to claim 7, wherein the step has a thickness equal to a thickness of the rotary weight body more than a thickness of a portion of the rotary weight located on an outer peripheral side of the overlapping portion. A rotary weight characterized by being thin by the minute. 9. The method according to claim 1, wherein
The oscillating weight is made of stainless steel, and the oscillating weight is made of tungsten. 10. The rotating device according to claim 1, wherein the laser welding portion is formed at a plurality of positions along an overlapping portion between the rotating weight body and the rotating weight. Weight. 11. The laser welding portion according to claim 1, wherein the laser welding portion is formed so as to be linearly connected along an overlapping portion between the rotary weight and the rotary weight. And the rotating weight. 12. A timepiece comprising a display mechanism driven by kinetic energy when the rotary weight defined in claim 1 is rotated by an external force. 13. A power generator for converting kinetic energy when the rotary weight defined in any one of claims 1 to 11 rotates to electric energy, a secondary power supply for storing electric energy generated by the power generator, and A timepiece comprising: a timepiece that measures time using a secondary power supply or electric power supplied from the power generation device, and a display device that displays a result of the measurement. 14. The timepiece according to claim 13, wherein a back cover of the timepiece case is arranged so as to cover the outer surface side of the rotating weight body. 15. The timepiece according to claim 14, wherein at least a portion of the back cover of the timepiece case that covers a laser welded portion between the rotating weight and the rotating weight body is transparent. 16. The method of manufacturing a oscillating weight according to claim 1, wherein the laser welding step for fixing the oscillating weight and the oscillating weight is performed by an outer peripheral portion of the oscillating weight. After overlapping the rotating weight, the rotating weight is performed by irradiating a laser beam from the outer surface of the rotating weight body opposite to the side on which the rotating weight overlaps. Manufacturing method. 17. The method for manufacturing a oscillating weight according to claim 1, wherein the laser welding step for fixing the oscillating weight and the oscillating weight includes an outer peripheral portion of the oscillating weight and the oscillating weight. And then, by irradiating the laser beam toward the through hole from the outer surface of the rotating weight body opposite to the side on which the rotating weight is overlapped. Method of manufacturing a rotating weight. 18. The method for manufacturing a oscillating weight according to claim 2, wherein the laser welding step for fixing the oscillating weight and the oscillating weight is performed by an outer peripheral portion of the oscillating weight and the oscillating weight. And then, by irradiating a laser beam toward the bottom of the concave portion from the side of the outer surface opposite to the side on which the rotating weight overlaps on both surfaces of the rotating weight body. Method of manufacturing a rotating weight. 19. The method of manufacturing a oscillating weight according to claim 6, wherein the laser welding step for fixing the oscillating weight and the oscillating weight comprises an outer peripheral portion of the oscillating weight and the oscillating weight. And a laser beam directed to the through hole formed at the bottom of the concave portion from the outer surface of the both surfaces of the rotating weight body opposite to the side on which the rotating weight is overlapped. A method of manufacturing a rotating weight, wherein the method is performed by irradiating the rotating weight.