JPS585388B2 - Suishiyoudokei - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a quartz wristwatch that includes a crystal oscillator as a time standard, an electronic circuit, a step motor, a train wheel, etc., and particularly relates to a step motor and a train wheel.

The present invention relates to an electronic wristwatch that simplifies the time adjustment mechanism by rationalizing the wheel train and using a single-phase drive step motor instead of the conventional inverted pulse drive step motor as an electro-mechanical converter. .

An object of the present invention is to provide an inexpensive crystal wristwatch that is smaller, lower in cost, and lower in power by rationalizing the wheel train and adopting a single-phase drive pulse motor.

Currently, the mainstream time display method for quartz wristwatches is one-second movement using a step motor, and this method has been highly evaluated both in terms of reliability and product value.

However, in order for crystal watches to become more common and popular, there are several issues that need to be solved.One of them is the miniaturization of batteries and watch bodies due to lower power consumption. There's a problem.

For example, regarding the above method, the step motor is operated by passing a current of several hundred microamperes once every second for a very short time, so the power currently consumed for oscillation frequency division is The driving part consumes several times as much power as the previous model, and the current situation is that batteries with a considerably larger capacity are used to guarantee a battery life of one year.

The size of this battery affects the overall size of the quartz wristwatch, and for this reason, quartz wristwatches comparable to women's mechanical watches have not yet been realized.

Furthermore, not only women's wristwatches but also decorative wristwatches have size limitations with the current watch bodies, making it impossible to design them exactly as desired, and there has been a strong desire for the creation of small crystal wristwatches.

In consideration of the above, the present invention aims to realize a crystal wristwatch that is comparable to a ladies' mechanical watch by reducing power consumption and downsizing.

Hereinafter, the content of the present invention will be explained in detail.

Currently, many women's watches, especially the small ones, do not have a second hand, and even those that do have one have only a decorative meaning or to indicate that the watch is running. be.

If we consider a two-hand watch without a second hand, the driving method would be to drive a step motor every second, and after deceleration by the gear train, it would be possible to move the minute hand and the clock. It must be said that it is extremely wasteful to move the minute hand every second on a watch without a watch.

In other words, the rotation speed of the minute hand is 0.1°/sec, and since it is impossible to see the minute hand moving in steps with the naked eye, it is extremely difficult to see whether it is necessary to move the minute hand in such a detailed manner from the viewpoint of power consumption. is questionable, and is thought to have no practical meaning.

Here, the present invention replaces the conventional hand movement every second and adopts hand movement at arbitrary time intervals (for example, 2 seconds, 3 seconds, 5 seconds, 10 seconds, etc.), thereby reducing the amount of energy consumed by the driving part. This is an attempt to drastically reduce power consumption.

For example, if a step motor is operated by a drive signal every 5 seconds, passed through an appropriate reduction gear train, and then the minute and hour hands are operated, the power consumed by the drive part will be reduced compared to the conventional 1 second step. The total power is about 115, which makes it possible to realize a large reduction in power.

In this case, the minute hand moves stepwise once every 5 seconds, but since it is a small wristwatch, the minute hand is short and poses no practical problem.

As is clear from this example, by using a hand movement method other than 1-second movement, it is possible to significantly reduce power consumption, and therefore, if the lifespan is the same as before, the battery capacity will be significantly reduced. In addition, by using batteries with the same capacity as conventional batteries, the lifespan can be extended.

By the way, in conventional watches with a second hand, the second hand moves at a rate of 1 minute per minute.
Because it needed to rotate, there was a limit to the number of teeth on the gear to which the second hand was attached, and it was not possible to freely select the number of teeth.

Due to this and constraints on gear manufacturing, it has not been possible to manufacture gears that meet the designer's requirements in terms of shape (particularly size) in the past.

The three-hand type is advantageous in this respect as well, since there is no second hand, the reduction gear train from the step motor to the minute hand can use any reduction ratio in the middle, as long as the final reduction ratio satisfies the conditions. The degree of freedom in the gear train arrangement is greatly increased, and with appropriate design, this is also a novelty that will help miniaturize.

Furthermore, considering time adjustment, conventional models with a second hand generally stop the second hand using a regulation lever that is linked to the movement of the crown, and use a sliding mechanism installed in a part of the wheel train as the crown rotates. The minute and hour hands are rotated, but in a watch without a second hand, there is no need for a regulating lever or sliding mechanism, and by rotating the crown, the time can be adjusted by rotating the gear train and step motor in conjunction with each other.

Let us now consider the hand movement state after the time adjustment operation.6 Figure 1 shows an example of a conventionally used inversion pulse drive step morph.

21. 22 is a stator made of magnetic material, 23 is an N pole,
The rotor is made of a permanent magnet and the S pole is magnetized in the radial direction, and 24 is a drive coil.

In FIG. 1, when a drive current flows from the A terminal to the B terminal of the coil, N and S poles are generated in the stators 21 and 22, respectively, and the rotor 23 rotates clockwise by 180 degrees due to the repulsive force.

The position of the rotor 23 shown in FIG. 1 before rotation at this time is designated as the ■ position, and the direction of the flowing current is designated as the ■ direction.

On the other hand, the position when the rotor is rotated by 180 degrees from the rotor position shown in FIG. 1 is the e position, and the current direction from B to A is the ○ direction.

At this time, the relationship between the current direction and the rotor stop position is as shown in FIG.

As mentioned above, when using a reversing pulse drive step motor, the current direction that can be operated for each stable position of the rotor is determined, and when the rotor is stopped at the doesn't work.

Because of this and because the direction of the first pulse after the time adjustment operation is canceled is determined, when using reverse pulse drive, the first pulse is used depending on the rotor's stop position after time adjustment. Two cases occur: when it starts, and when it starts to move at the second pulse.

In such a case, there is no practical problem if a 2-second or 3-second hand movement is adopted, but if the hand movement is 5 seconds or more, especially 10 seconds or more, the error becomes noticeable and is inconvenient.

Here, we replaced the conventional inverted pulse drive step motor with
The problem is solved by using a single-phase drive.

3 is a schematic plan view of the above-mentioned single-phase drive pulse motor, and FIG. 4 is a sectional view taken along line PP in FIG. 3.

In the figure, 31.32 is a stator made of magnetic material, 3
3 is a rotor made of a permanent magnet, a driving coil is provided, and a positioning ring 35 is made of a permanent magnet for determining the position of the rotor when it is at rest.

In FIG. 1, when a current flows through the drive coil in the direction from A to B, the stators 31 and 32 have N and S poles, respectively, and the rotor is repulsed and begins to rotate clockwise.

At this time, if the time length (pulse width) of the current applied to the coil is set appropriately, it will continue to rotate over the same pole of the positioning ring 35 located at a place rotated 180 degrees from the stop position in an emergency, and eventually rotate 360 degrees, that is, Rotate once and stop.

Therefore, if a current is passed in the same direction next time, it will rotate once and perform the same operation thereafter.

As mentioned above, this motor is driven by single-phase pulses, so
The inconveniences that occur when using the inverted pulse drive motor described above do not occur.

The present invention has been described in detail above, and its features can be summarized as follows: 1. By adopting a hand movement method other than 1-second movement, it is possible to significantly reduce power consumption, resulting in smaller batteries and a smaller watch body. can be measured.

2. For a two-hand watch, apply 1. above. By implementing this, it is possible to freely design the gear, omit the regulation lever, and the sliding mechanism, making it possible to reduce the size, thickness, and cost.

3. Particularly for intermittent movement with long intervals, by using a single-phase drive step motor, accurate hand alignment can be achieved without using any special equipment.

As described above, according to the present invention, the watch body can be made smaller and thinner,
The significance of this is extremely significant as it can reduce costs.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view of a conventional inversion pulse drive step motor. FIG. 2 is a diagram showing the relationship between drive pulses of a conventional step motor and rotor stop position. FIG. 3 is a schematic plan view of a single-phase drive step motor according to the present invention. FIG. 4 is a schematic sectional view taken along line PP in FIG. 3. 21.22... Stator, 23... Rotor, 24... Drive coil, 31, 32...
...Stator, 33...Rotor, 34...
... Drive coil, 35 ... Positioning magnet.

Claims (1)

[Claims] 1 Consisting of a time standard crystal oscillator, an electronic circuit, and a step motor, the step motor is driven by single-phase pulses at time intervals of 2 seconds or more supplied from the electronic circuit, and there is no regulating lever for regulating the wheel train. , a crystal wristwatch characterized by the absence of a friction sliding mechanism of the wheel train, and a two-hand display of only the hour and minute hands.