JPS5832186A - Analog electronic timepiece - Google Patents

Abstract

PURPOSE:To eliminate intermediate stopping by applying stabilizing pulses for preventing intermediate stopping in the direction opposite from driving pulses after application of the driving pulses. CONSTITUTION:After driving pulses 20 are applied to the coil of a step motor, stabilizing pulses 25, 26 for preventing the intermidiate stopping of a rotor are applied to the coil. While the rotor is at a static stable point, the detection pulses for detecting the position of the rotor are applied to the coil. If it is decided that the rotor is not in revolution, a correcting pulse 28 is applied to the coil to rotate the rotor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an analog electronic watch, and more particularly to a method for determining the position of a rotor of a step motor, which is an electromechanical conversion mechanism thereof. In other words, by increasing the reliability of position determination and driving the step motor with the optimal pulse width while ensuring absolute reliability in hand movement, it is possible to reduce the power consumption of analog electronic watches. This is what I am trying to do.

No. tg shows a step motor of an analogue electronic watch which has been conventionally and generally used and is also used in the present invention. ．． It is composed of a stator 3, and the stator 3 has inner notches 5-a and 5-b.

It has outer notches 4-a and 4-h. When the coil is not energized, the rotor 2 is stopped in a direction that makes approximately 90'' with the direction connecting the two inner notches.

As shown in Fig. 2, pulses of different polarity are normally sent to the coil 1 alternately every 1□□□, and the rotor 2
It rotates one by one and drives the gear train. Conventionally, as shown in FIG. 2, this drive pulse is always applied as a pulse of a constant width, regardless of the load condition and the output torque condition of the motor.

(48m5ec in 2nd I!i!) This drive pulse width is set with a sufficient safety factor so that the step motor can rotate normally even when a large load is applied, such as when driving a calendar mechanism. has been done. As a result, a considerable amount of wasted current is consumed, especially during normal employee load times. In addition, at low temperatures, the power supply voltage decreases due to an increase in battery internal resistance, so the motor drive pulse width must be set in advance so that an output torque with sufficient margin is produced, taking into account this reduction in motor output torque. ing.

This also results in wasted current consumption at low temperatures. Furthermore, it is also necessary to take into consideration in advance the increase in frictional load due to aging.

In any case, more current is consumed than necessary to maintain a high degree of safety in normal rotation of the motor, and this has been an obstacle to reducing the power consumption of the gummy child clock. As a means of solving this problem, the drive is usually performed with a shorter pulse width than the conventional one, and the next drive pulse after rotation is the same or even wider than the previous one, so that the load state S! A method has been considered in which the stepper is driven with an optimal pulse width depending on the state of the output torque of the seven motors. The most important thing in realizing drive with the maximum pulse width is to determine whether or not the rotor has rotated. Conventionally, to determine whether or not the rotor is rotating, A method for determining this has been proposed.

In this method, as shown in FIG. 5, a driving pulse 6 is applied, and after the transient vibration of the rotor due to this driving pulse ends
When the sun is stationary, the position of the rotor is determined by detection pulses 7, and if it is not at the desired position, a correction pulse 8 is issued to ensure normal hand movement.

Now, regarding this method of determining the rotor position, if the rotor is now in the position as shown in Figure 4, when the coil is excited by the drive pulse, the magnetic flux due to the drive pulse is 15
occurs as shown in the figure. If the 0 o'clock drive pulse is sufficiently large, the rotor will rotate 180 degrees and take the position shown in FIG. 5 (-). Now, when a detection pulse is issued to determine the 9th position of the rotor in the state shown in FIG.

12-h (near D, the magnetic flux generated by the rotor magnet 5
14-m and 14-b, the magnetic resistance is small, so the inductance of the coil is large, and the current caused by the detection pulse shows a gentle rise.On the other hand, the drive pulse width is insufficient and the rotor Let us consider a case where the object does not rotate and assumes the position shown in Fig. 5(b). In this case, near the outer notch, the magnetic flux generated from the rotor magnet is opposite to the case (α), and is in the same direction as the magnetic flux due to the detection pulse, so the magnetic resistance is large, and the coil inductance is therefore small. . Therefore, the current caused by the detection pulse shows a rapid rise. By determining the difference in the rise of this detected current, the position of the rotor is determined, and whether the rotor is rotating or not is determined.

However, as is well known, the pulse width control function always functions to supply the minimum pulse width necessary to rotate the rotor, so after the drive pulse is applied, the
Not only the state shown in the figure (-) or the state shown in (h) (6th
There are cases where the position shown in the figure is taken. This means that the center position of the rotor's magnetic poles is the neutral point, that is, the two inner notches It
-ex.

It has stopped in the direction connecting 11-h. (This phenomenon will be referred to as an intermediate stop from now on.) Since this position is not a stable point, if there is any disturbance, such as mechanical vibration or magnetic disturbance, it will immediately fall to one of the stable points. However, if there is no such disturbance, it will try to stay at the neutral point forever.

Now, if a detection pulse is issued in this state, the magnetic fluxes 18-a and 18-b generated from the rotor magnets are opposite to the magnetic flux 19 caused by the detection pulse near the outer notch. This state is magnetically similar to the case where the rotor rotates in FIG. 5(α). Therefore, the current caused by the detection pulse shows a gentle rise similar to when the rotor rotates, and it is determined that the rotor has rotated. When it is determined that the rotor has rotated, the next drive pulse with the opposite polarity is issued after 1 second without issuing a correction pulse, so that the p-y is pulled back to its original position, and the clock ends up clocking in at 2 seconds. This will result in a delay. If the displayed time is longer than the official time, it is a fatal flaw in a quartz watch where accuracy is an absolute mission. In addition, this phenomenon of stopping in the middle occurs in pulse width control, as the number of pulse widths prepared in advance as a pulse train increases.
Furthermore, the greater the load on the gear train due to aging, etc., and the lower the temperature (because the viscosity of II lubricant increases), the higher the probability of occurrence, and therefore the possibility of a delay in hand movement. is getting higher.

The present invention aims to eliminate such conventional drawbacks, to determine whether the rotor is rotating or not, while ensuring absolute reliability of hand movement, and to contribute to lower power consumption of step motors. Specifically, after applying the drive pulse, a stabilizing pulse for preventing intermediate stop is applied before the detection pulse, thereby eliminating the phenomenon of intermediate stop and ensuring absolute reliability of detection. The present invention will be explained below with reference to the drawings.

@7 Figure is one embodiment of the present invention, and shows the pulse waveform applied to the coil. In the figure, 20 is a driving pulse, 2
The pulse number 1 is the core of the present invention, and the pulse number 9 is a pulse that attempts to return the rotor to a static stable point when an intermediate stop occurs. (This is called a stabilizing pulse.) 22 is a detection pulse, and 23 is a correction pulse. The correction pulse is used when it is determined by the detection pulse that the rotor is not rotating.

The drive pulse 20 is output with a pulse width that is predicted to be most suitable from among several pulse widths prepared in advance based on the load condition and output torque condition of the motor at that time. Now, if this drive pulse 20 is sufficient to rotate the rotor, the rotor will rotate 180 @ as shown in Figure 8, and the hands will move normally. It shows the negative displacement of the rotor's magnetic pole center (see Figure 1), where 0=o@ is the static stable point, 0=
180@ is another static stable point, #=? O@ indicates the neutral point that is a problem in the present invention. In this case, the correction pulse 2! is determined to be a detection pulse 22-□ rotation! I is not output. FIG. 9 shows a case in which the drive pulse 20 is insufficient for the rotor to rotate, contrary to FIG. - In the evening, the hands rotate 180 degrees to ensure normal movement. Figure 10 shows that the output torque due to the drive pulse 20 and the load torque are just balanced, and the
This shows the so-called intermediate stop O case where the vehicle stopped at the neutral point of to°. When an intermediate stop occurs in this way, in the present invention, after 200 driving pulses, a stabilizing pulse 21 is prepared to return the rotor to a static stable point, so that the rotor is returned to a static stable point of θ=00. pulled back to a stable point. Therefore, the detection pulse 22 determines whether the rotor is not rotating, and the correction pulse 25 is output. Since this correction pulse is set to produce sufficient output torque, the rotor always rotates and moves to the #=180° position, ensuring normal hand movement. Therefore, by providing a stabilizing pulse in the drive pulse as in the present invention, it is possible to solve the problem of intermediate stops, which conventionally caused even-numbered seconds. Therefore, the reliability of hand movement is absolute.

Next, regarding the direction in which the stabilizing pulse is issued, there are two possibilities: one in the positive direction with respect to the drive pulse, and one in the opposite direction as in the present invention. It has been confirmed that outputting in the direction is overwhelmingly more effective; that is, a stabilizing pulse with a narrower pulse width can prevent one intermediate stop. This is because when an intermediate stop occurs, the load on the gear train is smaller when the rotor is pulled back than when it is rotated, and also because the magnetic potential curve is different from the direction in which it is trying to rotate and the direction in which it is pulled back. Possible reasons include that there is an asymmetrical relationship between the two. In any case, it is more effective to output the stabilizing pulse in the direction opposite to the direction of the drive pulse as in the present invention for intermediate stops.

Furthermore, when the detection pulse determines the rotor position, the stabilization pulse is output in the opposite direction to the drive pulse, raising concerns about detection instability due to the magnetic history of the stabilization pulse. However, as described above, since the stabilizing pulse issued in the opposite direction may have a very narrow pulse width, instability of detection due to magnetic history is not a problem.

Next, in the present invention, since a stabilizing pulse is provided in addition to the detection pulse, there is a concern that the current consumption will increase.
For example, the detection pulse should be 136, and the stabilization pulse should be a24.
According to experiments, when the setting is ssec, the average current consumption due to the detection pulse is 14m, and the average current consumption due to the stabilization pulse is 10m, which is very small, 24n in total. In the previous explanation, the stabilizing pulse, which is the core of the present invention, is singular, but as an example shown in FIG. 11, the stabilizing pulse is Even if a plurality of 25 and 26 are applied, there is no harm to the effect of the present invention and it does not go beyond the scope of the present invention.As explained above, according to the present invention, the driving force is By applying a stabilizing pulse for intermediate stop spinning in the drive/(-s) and 1st direction after applying , it is possible to eliminate intermediate stops, which conventionally caused delays in hand movement.Also, the stabilizing pulse Since the width of the voltage may be very small, there is no need to worry about an increase in current consumption due to the addition of a stabilizing wave. As described above, the present invention can be applied to analog electronic watches without any cost increase factor, and is extremely practical.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the step motor of an analog electronic watch.
Figure 2 shows the conventional step motor drive waveform. FIG. 5 shows the drive waveform of a conventional step motor having a pulse width control function. Figure 4. Figure 5, dv! i is an operation diagram of a step motor, and FIG. 7 is a voltage waveform applied to a coil showing an embodiment of the present invention. FIGS. 8, 9, and 1011 are diagrams showing the angular displacement of the rotor and the voltage waveforms applied to the coils. FIG. 11 is a diagram showing a voltage waveform applied to a coil according to another embodiment of the present invention. 1...Coil 2...-Rotor 3...Stator 4-a, 4-h...Outer notches 5-a, 5-b...- Inner notch 4.6'... Drive notch 7.7'... Detection pulse 8.8'... Correction notch!... Rotor 10... Stator 11-5, 11-A... Inner notch 12-IP
-si, 12-b... Outer notch 15...
...Magnetic flux 14 1"e'4' due to drive pulse
...Magnetic flux due to rotor magnet 15...Magnetic flux due to detection pulse 16-a, 16-b...Magnetic flux due to rotor magnet 19-g, 18b...Rotor magnet The magnetic flux 'IQ, 20'......driving) (Rus gl, no 1'......stabilization) (Rus 22.22
'...Detection) (Rus 25.25'...
Correction) Kurusu 24.24'... Drive no (Rusu 2
5.25', 26,76'... Stabilization pulse 27.27'... Detection pulse 28.28'... Correction pulse. Applicant Kinsha Suwa Seikosha Co., Ltd. Agent Patent Attorney Mogami Musagi Otsukushi 1 RL Kaikyo 'i3 Ou 2 o Hana 9th

Claims (1)

[Claims] After applying a drive pulse, the detection pulse determines whether the rotor is rotating or not, and the width of the drive pulse is controlled. An electronic clock whose device is to apply a stabilizing pulse for intermediate stop spinning in the opposite direction to the driving pulse.