JPS6153669B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the arrangement of a three-hand analog electronic timepiece equipped with a step motor as an electromechanical converter. In particular, the present invention is intended to realize a three-hand ultra-compact analog crystal watch such as a ladies' bracelet watch.

In recent years, a crystal oscillator is provided as a time standard oscillator, the signal from the oscillator is divided into a relatively low frequency signal by a frequency dividing circuit, and the pulse current shaped by the signal is used to generate a signal. Analog crystal clocks that drive step motors, wheel trains, and pointer mechanisms are rapidly becoming popular.

However, in the analog quartz clock mentioned above, parts such as the battery, crystal oscillator, IC chip, and coil and stator, which are the components of the step motor, occupy a large volume, so the conventional analog quartz clock movement When adopting such an arrangement structure, it was extremely difficult to make the watch sufficiently compact. Therefore, at present, a three-hand bracelet crystal watch equipped with a second hand that moves in steps every second has not yet been realized.

An object of the present invention is to provide an arrangement structure for a three-hand electronic timepiece that can make maximum use of the limited space of a timepiece movement. It becomes possible to provide a small 3-hand analog crystal watch.

Hereinafter, details of the present invention will be explained according to the drawings.

FIG. 1 is a plan view schematically showing the arrangement structure of a three-hand analog quartz watch according to an embodiment of the present invention, and FIGS. 2a and 2b are sectional views showing essential parts, respectively. In addition, in FIG. 1, the pitch circle of the so-called front gear train, which extends from the rotor pinion 7b to the second gear 11a, is shown by a thin line, and from the second pinion 11b to the cylinder pinion 15 and hour wheel 16.
Regarding the so-called rear gear train, its pitch circle is shown with a chain double-dashed line.

In each of the above figures, 1 is the base plate, and the base plate 1
As shown in FIG. 1, it has a planar shape in which the lengths are different in the major axis direction and the minor axis direction. Therefore, a timepiece movement constructed using the main plate 1 as a substrate also has essentially the same planar shape as the main plate 1. A watch movement with such a planar shape is generally referred to as a barrel-shaped movement, but this has the advantage of giving a greater degree of freedom to the design of the exterior, so it is particularly suitable for women's bracelet watches, etc. It is ideal as a movement for ultra-compact watches such as.

Within the timepiece movement, the battery 2, the crystal oscillator 3, and the coil 4 that is a component of the step motor are arranged in different planar spaces, and are arranged in a form that follows the outer circumferential shape of the main plate 1. has been done. Of these, the battery 2 is placed slightly over the center of the timepiece movement, and is supported by the main plate 1 via a battery holder 5. On the other hand, the coil 4 is disposed on the ground plate 1, and a pair of stators 6 fixed to a stator support plate 6a are disposed in an area adjacent to the coil 4. Furthermore, a rotor 7 is provided surrounded by the stator 6, and together with the coil 4 and the stator 6, constitutes a step motor driven at 1 Hz. Here, the rotor pinion 7b of the rotor 7 is meshed with the fifth gear 8a constituting the fifth wheel & pinion 8.
is supported by the main plate 1 and the gear train bridge 18. Further, the fifth pinion 8b of the fifth wheel & pinion 8 meshes with the fourth gear 9a forming the fourth wheel & pinion 9, and also meshes with the second gear 19a forming the second hand wheel 19 to which the second hand is attached. Therefore, the driving force transmitted from the rotor pinion 7b is input to both the fourth wheel & pinion 9 and the second hand wheel 19 via the fifth wheel & pinion 8. Also, the fourth kana 9 of the fourth wheel 9
b meshes with the third gear 10a that constitutes the third wheel & pinion 10, and the third pinion 10b meshes with the second wheel & pinion 11.
It meshes with the second gear 11a that constitutes the second gear 11a. As described above, the main transmission path for driving the front wheel train mechanism is constituted by the wheel train elements that extend from the rotor pinion 7b through the fifth wheel & pinion 8, fourth wheel & pinion 9, and third wheel & pinion 10 to the second gear 11a. Apart from the main transmission route,
A second hand wheel 19 is provided which is driven by the fifth pinion 8b. Further, the second hand wheel 19 is supported in two places in the radial direction by hollow posts 1a planted in the main plate 1, and further in the axial direction by the hollow posts 1a planted in the train wheel bridge 18, and is supported in the head part. is received by the D-shaped cutout 18a and the post 1a.

On the other hand, the battery 2 is arranged so that a part thereof overlaps a part of the second gear 19a in a plane, and in cross section, it is arranged above the second gear 19a, that is, on the back cover 22 side. . Also battery 2
The flat space occupied by the second hand wheel 1 extends to the center of the watch movement.
It has become difficult to provide a bearing portion for receiving the wheel train 9 in a part of the train wheel bridge 18 with a conventional structure. For this reason, in this embodiment, the battery 2
According to the direction of the slope portion 2a of
By protruding the head of 8a, the second hand wheel 1
9 is received in the axial direction. In this case, it is difficult to install a conventional bearing in the gear train bridge 18, but if the planar space occupied by the battery does not completely overlap the center of the watch movement, 18 or the lower surface of the circuit board 20 may directly receive the second hand wheel 19 in the axial direction.

On the other hand, the second gear 11a mentioned above is the second gear 11b.
It is constructed so that it can be slipped onto each other,
The second pinion 11b meshes with the small iron transmission wheel 12. Further, the rear wheel train mechanism of the watch of this example includes, in addition to the second pinion 11b and the small iron transmission wheel 12, a small iron wheel 13, a hour wheel 14, a tube pinion 15, and an hour wheel 1.
6, and the driving force is also transmitted in the above order. Further, when adjusting the time, the gear wheel 17 meshes with the small iron wheel 13, and at this time, a brake (not shown) is engaged with a part of the front wheel train, and the second gear 11a and the second gear 11a are engaged with each other. The second pinion 11b will slip against each other.

On the other hand, a circuit board 20 is disposed on the upper surface side of the gear train bridge 18, and the crystal resonator 3, IC chip 21, other electrical elements (not shown), etc. are mounted on the circuit board 20. is listed.

As described above, the gist of the present invention is to provide a three-hand analog electronic watch equipped with a step motor driven at 1 Hz as an electromechanical converter. A second hand wheel is provided separately from the main transmission path of the driving force of the wheel train, and is arranged so that a part of the second wheel constituting the second hand wheel and a part of the battery overlap in a plane, and in cross section The battery is placed on the back cover side relative to the second hand gear.

Therefore, according to the present invention, it is possible to realize an ultra-small crystal watch with a small planar space, and it is also possible to minimize the increase in the thickness of the watch. In contrast to the present invention, in a conventional arrangement structure in which the second hand wheel also serves as a so-called fourth wheel and constitutes a part of the main transmission path of driving force in the front wheel train, The second hand wheel, or fourth wheel, located in will be hindered. That is, in the conventional structure as described above, it is necessary for the battery to be placed so as to avoid not only the second gear but also the bearing portion above the fourth pinion and the second hand wheel.
However, in the space that corresponds to the slope of the battery,
It is impossible to accommodate both the fourth pinion and the bearing, and in the end, the battery must be disposed completely away from the fourth pinion and the bearing in a plan view, or in a cross-sectional manner. It will have to be installed. As a result, it is clear that the planar size of the watch increases if it is avoided in a plane, and the thickness of the watch increases significantly if it is avoided in a cross section.

On the other hand, in the present invention, the driving force transmitted from the rotor 7 to the second hand wheel 9 is configured to be input to the second wheel 19a via the third pinion 8b. On the other hand, in a wheel train configuration where the driving force is input to the second hand pinion instead of the second gear, it is difficult to drive the step motor at 1 Hz and move the second hand in steps every second. Become. In other words, in such a gear train configuration, the reason why the second hand pinion, which has a small number of teeth, is rotated by a fixed angle every second is due to the fact that the rotation angle corresponding to the backlash of the second hand pinion is extremely large, and the shape of the tooth profile. This is because it is practically impossible due to the difficulty of constant speed rotational drive. In the present invention, it is clear that in order to accurately rotate the second hand wheel by a constant angle of 6 degrees every second, it is desirable that the number of teeth on the second gear 19a be 30 or an integral multiple of 60. In particular, a number of 60 teeth is optimal, as the feed of one tooth profile corresponds to one second of hand movement. Also, if the number of teeth is 30, 1
It is possible to divide the teeth into two parts and feed them in half, but in that case, it is preferable to use a six-pole type step motor due to the problem of the tooth number ratio of the other gear trains.

On the other hand, the timepiece movement having the arrangement structure of the present invention is advantageous in terms of the thickness of the timepiece even when the second hand is removed and the movement is used as a two-hand timepiece movement having only hour and minute hands. Here, FIG. 3 shows a sectional view of a main part when the three-hand analog quartz watch shown in FIGS. 1 and 2 is converted into a two-hand clock. In this example, the second hand wheel 19 is removed, the battery receiver 5' is changed to one with a thickness of t, and the battery pressing spring 23 is also replaced accordingly. In other words, in small electronic watches, the volume occupied by the battery is significantly larger than that of other components, so the movement structure is such that only the battery protrudes toward the back cover, and the top surface of the battery ends up being The shape determines the thickness of the watch. Therefore, in the timepiece having the arrangement structure of the present invention, by replacing the battery receiver 5' with a thinner one as shown in FIG. 3, the space created by removing the second hand wheel 19 can be filled. It becomes possible to lower the position of the battery 2, and if the watch is eventually used as a two-hand watch, it becomes possible to further reduce the thickness of the watch. On the other hand, a movement for a three-hand watch that has a conventional layout structure also has the fourth pinion of the second hand wheel, which forms part of the main transmission path for the driving force of the front wheel train. Because we are
Even if the movement is used as a two-hand watch movement, it is impossible to remove the second hand wheel, and the two-hand movement is significantly disadvantageous in terms of thickness.

Note that when a movement for a three-hand watch is generalized and used for a two-hand watch as in this example, the current consumption can be reduced by changing the drive cycle of the step motor to a longer cycle. It is also possible to measure savings. In that case, the tooth ratio of the front wheel train may be changed to an appropriate value, and the drive pulse width of the motor may be changed as necessary.

As described above, the arrangement structure of the present invention is not only effective as a three-hand analog electronic watch itself, but also has two
It is also advantageous in terms of the versatility of the watch movement when considering the use of hands.

[Brief explanation of the drawing]

FIG. 1 is a plan view schematically showing the arrangement structure of a three-hand analog crystal watch according to an embodiment of the present invention. Second
Figures a and b are cross-sectional views showing the main parts thereof. Third
The figure shows a second watch with the second hand wheel removed from the watch of the above embodiment.
FIG. 3 is a cross-sectional view showing the main parts when the needles are formed. 1...Main plate, 2...Battery, 3...Crystal oscillator,
4...Coil, 5,5'...Battery holder, 6...Stator, 7...Rotor, 7b...Rotor pinion, 8...5th wheel, 9...4th wheel, 10...3rd wheel , 11...Second wheel, 11a...Second gear, 18
... Gear train bridge, 18a... Beyond, 19... Second hand wheel, 19a... Second gear, 22... Back cover.

Claims (1)

[Scope of Claims] 1. In a three-hand analog electronic watch equipped with a step motor as an electromechanical converter, the main transmission of the driving force of the front wheel train from the rotor pinion constituting the rotor of the step motor to the second gear A second hand wheel is provided separately from the route, and is arranged so that a part of the second gear constituting the second hand wheel and a part of the battery overlap in a plane, and in cross section, the battery is placed on the back cover with respect to the second gear. 3 characterized by being placed on the side
Arrangement structure of hands analog electronic clock. 2. The arrangement structure of a three-hand analog electronic timepiece according to claim 1, wherein the second gear has 60 teeth. 3. The arrangement structure of a three-hand analog electronic timepiece according to claim 1, wherein the step motor is of a six-pole type, and the second gear has 30 teeth.