JPH06281757A - Motor control circuit of electronic clock - Google Patents

Abstract

PURPOSE:To improve the possessing torque of a display wheel and the indication accuracy of a hand with a motor having a small space by generating first and second drive pulses to detect the rotation of a step motor and setting the output spacing to a specific value or less. CONSTITUTION:A terminal O1 outputs a step motor drive pulse P1a in normal operation and then, whether the step motor rotates or not is detected by pulse P2a. A terminal O2 also outputs a step motor drive pulse P1b to detect the rotation of the step motor with a pulse SP2b. Then, only when the step motor is not rotated by the pulse P1a (P1b), a compensation drive pulse P2a (P2b) is output from the terminal O1 (O2), thus rotating the step motor, where a rotar constituting the step motor is rotated by 360 deg. within one second and the deceleration ratio from the rotar to a second display wheel is doubled as compared with before. Also, the output timing of two pulses P1a and P1b for rotating the rotar is set to 50ms or less, thus improving the possessing torque of a display wheel and the indication accuracy of a clock hand.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control circuit for electronic timepieces.

[0002]

2. Description of the Related Art A conventional motor control circuit structure is one second per second.
One drive pulse is output once, and 1 pair with this pulse
One correction drive pulse is provided.

[0003]

However, the conventional techniques have the following problems.

In the structure of the reduction gear train from the rotor, the meshing portion of each gear is always prevented from the standard setting state in order to prevent the gear meshing portion from being squeezed and biting due to factors such as variations in parts and tooth profile accuracy. It is necessary to secure a clearance (hereinafter referred to as backlash). Therefore, due to the backlash between the teeth, the second display position is displaced and the dial is displaced.

This is because the normal rotor movement is shown in FIG.
The rotor is not driven every 180 °, as shown in the figure), which shows a single movement of a two-pole rotor that reverses every °, but after the rotation, it is damped by repeating vibrations to a stable point. Since the vehicle is stationary, the second display vehicle is also stationary while vibrating through the reduction gear train.

However, due to the above-mentioned backlash of each gear, even if the rotor accurately stops at the stable point, in the second indicating wheel, when the amplitude width of the rotor is attenuated and becomes smaller than the rotation amount due to the gear backlash, It no longer follows the movement of the rotor.

For this reason, the stationary position of the display vehicle varies in the range of backlash.

Further, if an attempt is made to increase the torque possessed by the display vehicle by the conventional motor control circuit structure, the torque possessed by the rotor is increased, and a coil block wound with more coils is required to rotate the rotor. It will require plane and cross sectional space.

The present invention solves the above problems, and its object is to indicate the origin of the hands, which can be said to be the origin by a motor in a small space, while the basic performance of watches is being reviewed in the market in recent years. (EN) A motor control circuit structure for an electronic timepiece, which improves accuracy and increases the torque possessed by a display vehicle.

[0010]

A motor control circuit for an electronic timepiece according to the present invention has a detection means for generating first and second drive pulses, each drive pulse detecting rotation of a step motor. And the output interval of the second drive pulse is 50 ms or less.

Further, the correction drive pulse of the first drive pulse is output after the second detection means, and the correction drive pulse of the second drive pulse is output after the correction drive pulse of the first drive pulse.

When at least one of the first and second detecting means detects non-rotation of the motor, at least one or more correction drive pulses for the first and second drive pulses are output.

[0013]

FIG. 1 shows a timing chart of an embodiment of the present invention.

O1 and O2 are the terminal names of the terminals from which the drive pulses of the step motor are output.

The motor control circuit outputs each pulse described below from the O1 terminal and the O2 terminal at the timing shown in FIG.

The pulse P1a is a normal step motor drive pulse output from the O1 terminal.

The pulse SP2a is a pulse output from the O1 terminal for detecting whether or not the step motor is rotated by the pulse P1a.

The pulse P1b is a normal step motor drive pulse output from the O2 terminal.

The pulse SP2b is a pulse output from the O2 terminal for detecting whether or not the step motor is rotated by the pulse P1b.

From the output start of the pulse P1a to the pulse P1b
The motor control circuit is configured so that the time until the start of the output of 50 is less than 50 msec.

The pulse P2a is a correction drive pulse that is output from the O1 terminal only when the step motor is not rotated by the pulse P1a and that rotates the step motor.

The pulse P2b is a correction drive pulse that is output from the O2 terminal only when the step motor is not rotated by the pulse P1b and is for rotating the step motor.

The step motor is composed of a coil, a stator and a rotor.

Normally, the second hand of analog quartz moves every second.

In order to move the second hand every second without impairing this movement, and to increase the torque possessed by the second indicating wheel, the rotor is rotated 360 ° within 1 second to reduce the speed reduction ratio from the rotor to the second indicating wheel. I have doubled.

The output timing of the pulses P1a and P1b for rotating the rotor is set to 50 ms or less at which humans cannot recognize that two pulses are being output by the movement of the second hand.

FIG. 3 shows a block diagram of an embodiment of the present invention.

The terminal 321 is connected to O1 in FIG.
1 terminal 321), the terminal 322 is O in FIG.
2 (hereinafter referred to as the O2 terminal 322).

The frequency of the original vibration obtained from the oscillator circuit 301 is created by the frequency dividing circuit 302, and the timing control circuit 303 controls the timing of the entire circuit. .

In the P1a + SP2a generation circuit 304, O
The drive pulse P1a output from the first terminal 321 and the rotation detection pulse SP2a for detecting whether or not the step motor 320 is rotated by the drive pulse P1a are generated by the rotation detection circuit 312.

In the P1b + SP2b generation circuit 305,
The drive pulse P1b output from the two terminal 322 and the rotation detection pulse SP2b for detecting whether or not the step motor 320 is rotated by the drive pulse P1b are generated by the rotation detection circuit 312.

In the P2a generation circuit, the correction drive pulse P2a output from the O1 terminal 321 shown in FIG. 1 is created.

In the P2b generation circuit, the correction drive pulse P2a output from the O2 terminal 322 shown in FIG. 1 is created.

The polarity switching circuit 313 has a drive pulse P1.
a, rotation detection pulse SP2a, correction drive pulse P2a
Are output from the O1 terminal 321 and the drive pulse P1b, the rotation detection pulse SP2b, and the correction drive pulse P2b are output from the O2 terminal 322, respectively.

In the rotation detection circuit 312, the drive pulse P1
Whether or not the step motor 320 is rotated by a or P1b is detected by the rotation detection pulse SP2a or SP2b, and the output permission / prohibition of the correction drive pulse P2a or P2b is controlled according to the result.

The polarity switching circuit 313 has a drive pulse P1.
a, rotation detection pulse SP2a, correction drive pulse P2a,
Is output from the O1 terminal 321 and each of the drive pulse P1b, the rotation detection pulse SP2b, and the correction drive pulse P2b is output from the O2 terminal 322.

Next, a method of controlling each pulse will be described.

FIG. 4 is a timing chart showing the operation of each circuit in FIG.

First, the timing control circuit 303 outputs a correction pulse output permission signal 324 (hereinafter referred to as a total correction permission signal 324) output from the rotation detection circuit 312 and a correction drive pulse P2b permission signal 325 (hereinafter P2b permission signal). 325) is set to Low,
Polarity control signal 326 output from the polarity switching circuit 313
Is set to High.

Next, the drive pulse P1a is applied to the O1 terminal 321.
When the step motor 320 is rotated, the total correction permission signal 324 is held at Low.

Then, since the AND gate 309 becomes Low, the correction drive pulse P2a is not output.

Thereafter, the polarity control signal 326 becomes Low within 50 ms immediately before the drive pulse P1a is output, and then the drive pulse P2b is output from the O2 terminal 322.

When the stepping motor 320 is rotated by the drive pulse P1b, the P2b permission signal 325 is held at Low, so that the correction drive pulse P2 is obtained.
b is not output.

As described above, when the step motor 320 continues to rotate by the drive pulses P1a and P1b, the correction pulses P2a and P2b are not output.

FIG. 5 shows a timing chart of the block diagram 3 when the step motor 320 is not rotated by the drive pulse P1a.

When the step motor 320 is not rotated by the drive pulse P1a, the output of the drive pulse P1b is prohibited and the output of the correction drive pulses P2a and P2b is permitted because the entire correction pulse permission signal 324 becomes High. To be done.

Therefore, when the step motor 320 is not rotated by the driving pulse P1a, the stepping motor 320 is rotated by the correction driving pulse P2a output from the O1 terminal 321 and then the polarity control signal 326 becomes Low and is output from the O2 terminal 322. The correction drive pulse P2b is controlled to rotate.

FIG. 6 shows a timing chart when the drive pulse P1a is rotating and the drive pulse P1b is not rotating.

Since the drive pulse P1a is rotated, the output of the correction drive pulse P2a is prohibited, and when the rotation is not performed at P1b, the P2b permission signal 325 becomes High, so that the correction drive pulse P2b is output from the O2 terminal 322. Is output.

Therefore, the step motor 32 is rotated by the drive pulse P1a and is not rotated by the drive pulse P1b.
0 rotates by the drive pulse P1a and the correction pulse P2b.

Although the present invention has been described in detail with reference to the embodiments, the present invention is not limited to the above embodiments.

For example, in the case of non-rotation by the drive pulse P1a, the drive pulse P1a and the rotation detection pulse SP2b are not prohibited, and 50 from the output of the drive pulse P1a.
The correction drive pulse P2a is output within ms, the drive pulse P1b is output within 50 ms after that, and the rotation detection circuit SP2b outputs the correction drive pulse P2b when non-rotation is detected in the rotation detection circuit 312. May be.

[0053]

The movement of the conventional second hand is carried out once a second by the second hand for 1 minute.

In the present invention, the rotor rotates twice as much as usual,
Since the output timing of the two pulses for doubling the speed reduction ratio from the rotor to the second indicator wheel and rotating the rotor is 50 ms or less, the second hand movement is the same as before, increasing the torque of the watch wheel, and moreover, the hand pointing accuracy Can be improved.

Further, except when the step motor is not rotated by the normal drive pulse, the correction pulse having a longer pulse width is not output, so that the power consumption is low.

[Brief description of drawings]

FIG. 1 is a timing chart of an embodiment of the present invention.

FIG. 2 is a motion explanatory view of a rotor.

FIG. 3 is a circuit block diagram of an embodiment of the present invention.

FIG. 4 is a timing chart showing the operation of the circuit block diagram of the embodiment of the present invention.

FIG. 5 is a timing chart showing the operation of the circuit block diagram of the embodiment of the present invention.

FIG. 6 is a timing chart showing the operation of the circuit block diagram of the embodiment of the present invention.

[Explanation of symbols]

P1a: First drive pulse P2b: Second drive pulse SP2a: Step motor rotation detection pulse by the first drive pulse SP2b: Step motor rotation detection pulse by the second drive pulse P1a: Correction drive pulse of the first drive pulse P1b: Second Drive pulse correction Drive pulse 303: Timing control circuit 304: P1a + SP2a generation circuit 305: P1b + SP2b generation circuit 306: P2a generation circuit 307: P2b generation circuit 312: Rotation detection circuit 313: Polarity switching circuit 320: Step motor 320 321: Terminal O1 322: Terminal O2

Claims (3)

[Claims] 1. An oscillating circuit for generating a reference signal, a frequency dividing circuit for dividing the reference signal, a pulse synthesizing means for synthesizing a pulse necessary for driving a step motor from the frequency-divided output, and a drive pulse. Step motor drive circuit,
In an electronic timepiece having a step motor driven by the drive pulse, a first drive pulse and first detection means for detecting rotation of the step motor by the drive pulse, and a second drive pulse and the drive pulse The timing control circuit and the pulse synthesizing circuit are configured so as to have second detecting means for detecting the rotation of the step motor, and the output interval of the first drive pulse and the second drive pulse is 50 ms or less. The motor control circuit of the characteristic electronic timepiece. 2. The pulse synthesizing means of claim 1 outputs a correction drive pulse for the first drive pulse after the second detecting means, and a correction drive pulse for the second drive pulse is corrected for the first drive pulse. A motor control circuit for an electronic timepiece, wherein a timing control circuit is configured to output after a drive pulse. 3. When the non-rotation of the motor is detected by at least one of the first detecting means and the second detecting means of claim 1, the output signal of the first or second detecting means is used. Controlling at least one drive pulse generation means and at least one correction drive pulse for the second drive pulse by controlling the drive pulse generation means and the correction drive pulse generation means. Motor control circuit for electronic timepieces.