JPS5833176A - Analog electronic time piece - Google Patents

Abstract

PURPOSE:To achieve a stable pointer operation preventing unwanted halt by controlling the application of stabilization pulses, correction pulses or the like according to the rotation or non-rotation detected on the rotor of a step motor. CONSTITUTION:When a step motor rotates by a drive pulse 20, the inductance of a drive coil decreases making the rise of a detection pulse 21 gentle thereby detecting the rotation of the rotor. This causes a stabilization pulse 22 to be applied to prevent the halt of the rotor. On the other hand, when non-rotation of the rotor is detected by a sharp rise of pulses 21, a correction pulse 23 is applied. Likewise, the rotation or non-rotation of the rotor is detected by a second detection pulse 24 and the rotor is driven to keep the stable rotation without halt. This prevents the generation of any halt thereby ensuring a stable pointer operation of an analog electronic time piece.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an analog electronic timepiece, and a method for determining the position of a rotor of a step motor which is an electromechanical conversion mechanism thereof. More specifically, the aim is to drive a step motor with an optimal pulse width while increasing the reliability of rotor position judgment and ensuring absolute reliability in hand movement, thereby reducing the power consumption of analog electronic watches. It is something.

Figure 1!1 shows a step motor for an analog electronic watch that has been commonly used in the past and is also used in the present invention.As shown in Figure 1, the step motor consists of a coil 1, a rotor 2 magnetized with two poles. The nutator 5 includes inner notches 5-a and 5-b.

Outside/Tsuchi has 4-a and 4-b. The coil is energized.
When not, the rotor 2 is stopped in a direction that is approximately 90 degrees to the direction connecting the two inner notches.

As shown in Fig. 2, pulses of different polarities are normally sent to the coil 1 alternately every 1 sec, and the rotor 2 rotates by 180 @ to drive the wheel train. Conventionally, this driving pulse is shown in Fig. s2. As shown, a pulse of a constant width is always applied regardless of the load state M and the output torque profile of the motor. (Second
(48 m5ec in the figure) This drive pulse width is approximately 100 m long when a large load is applied, such as when driving a calendar mechanism.

It is set with a sufficient safety factor so that the Nutep motor can perform normal rotational movement. Therefore, a considerable amount of wasted current is consumed, especially during normal low load conditions. Also, at low temperatures, the power supply voltage decreases due to an increase in battery internal resistance.

In consideration of the decrease in motor output torque caused by this, the drive pulse width of the motor is set in advance so that an output torque with a sufficient margin is produced. This is also a waste of current consumption under normal temperatures. Additionally, the frictional load increases due to aging.

Similarly, it is necessary to consider this in advance. In any case, in order to maintain a high degree of safety in normal rotation of the motor, there is a need for current consumption that exceeds the membership fee.

This is a major hindrance to reducing the power consumption of analog electronic clocks, and as a means to solve this problem, it is usually driven with a shorter pulse width than conventional ones, and the driving pulse after one revolution is the same as that of the rudder. A method has been considered in which pulses are supplied with narrow width pulses, and the spur motor is always driven with the optimum pulse width depending on the load condition and the output torque profile of the motor. The most important factor in realizing driving with such an optimum pulse width is determining whether or not the rotor has rotated. Conventionally, this rotation.

In order to determine non-rotation, a method of determining the O-ri position has been proposed. In this method, as shown in FIG. 5, a drive pulse 6 is applied, and when the transient vibration of the rotor due to this drive pulse has ended and the rotor is standing still, the position of the rotor is determined by a detection pulse 77, and the desired position is determined. This book attempts to ensure normal movement of the hands by issuing a correction pulse 8 when the hands are not in the correct position.

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. At this time, if the drive pulse is sufficiently large, the rotor 11180 rotates and assumes the position shown in FIG. 5 (,). When a detection pulse is issued to determine the position of the rotor in the state shown in FIG.
In the vicinity of b, a magnet 14-a is generated by the rotor magnet.

14-b, the magnetic resistance is small, and therefore the inductance of the coil is large, and the current caused by the detection pulse rises slowly.On the other hand, the drive pulse width is insufficient and the rotor is No rotation, Figure 5(b)
Consider a situation like this. In this case, near the outer notch, the magnetic flux generated from the rotor magnet is opposite to that in case (a) and points in the same direction as the magnetic flux due to the detection pulse, so the magnetic resistance is large and the inductance of the coil is small. Become. The current caused by this detection pulse shows a sudden rise.By determining the difference in the rise of this detection 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 functions to always supply the minimum pulse width necessary to rotate the rotor, so the state of drive (rotor brokerage after pulse application @ S diagram ←) In the state shown in (b) alone, the position shown in FIG. 6 may occur. The center of the rotor's magnetic poles is the neutral point.

In other words, it has stopped in the direction connecting the two inner notches 11-b and 11-b. (This phenomenon will be referred to as intermediate stop from now on.) This position is a stable point and F
Therefore, if there is some kind of disturbance, such as mechanical vibration or magnetic disturbance, it will immediately try to reach a stable point, but if there is no such disturbance at all, It tries to stay at a neutral point forever. Now, if a detection pulse is emitted at this tS, is it a low/magnet?
The magnetic fluxes 18-a and 18-b generated from the magnetic fluxes 18-a and 18-b in the vicinity of the outer notches are opposite to the magnetic flux 19 caused by the detection pulse. This state is magnetically uniform to the state shown in FIG. 5(a) when the rotor rotates. Therefore, the current caused by the detection pulse shows a uniform and gentle rise as when the rotor rotates, and the current is low! If it is determined that the rotor has rotated, no correction pulse is issued'!
After 11 seconds, the polarity was reversed and the next 0 WAIl! Because the pulse is emitted.

The rotor was pulled back to its original position, and the clock ended up being 2 seconds behind! The fact that the displayed time is later than the official time is a fatal flaw in quartz watches, where accuracy is an absolute priority.

In addition, in pulse width control, this phenomenon of intermediate stop occurs as the number of pulse widths prepared in advance as a pulse train increases, and as the load on the wheel train increases due to aging etc. The lower the temperature change (because the viscosity of the lubricating oil becomes higher), the higher the probability of 1 occurrence, and therefore the higher the possibility of a delay in hand movement.

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, this book attempts to eliminate intermediate stop tC and ensure absolute reliability of detection by applying a stabilizing pulse to prevent intermediate stop after the first detection pulse is issued. . The present invention will be explained in detail below with reference to the drawings.

The gy diagram shows a pulse waveform applied to a coil of one fiber of the present invention. -With 20Fi drive pulse in the figure,
Choose from several pre-prepared pulse widths to determine the current load condition and mode! The output torque is output with a pulse width that is expected to be most suitable based on the output torque state. 21 indicates the first detection pulse, 23 indicates the first correction pulse, and when the first detection pulse determines that the rotor is not rotating,
A correction pulse is output. 24 and 25 respectively indicate the second detection pulse and *2 correction pulse, when the @2 detection pulse determines that the rotor is not rotating.

A second correction pulse is output. 22 is a pulse that explains the core of this idea, and is a pulse that attempts to return the rotor to a static stable point when an intermediate stop occurs, as explained by Ilk. (This pulse t-stability will be referred to as a pulse.) The stabilizing pulse is configured to be output when the first detection pulse indicates that the rotor has rotated.

4111! If the PALNU 2o is sufficient to rotate the rotor and it is good, the rotor will rotate 180@ as shown in FIG. 8, and the hands will move normally. θ in the same layer indicates the angular displacement of the center of the rotor's magnetic pole from the static stable point, and is $1 (see Figure 1), θ-. @ indicates a static stable point, #-180@ indicates another static stable point, and θ-9011 indicates a neutral point that is a problem in the present invention. In Fig. fii1, since the *- detection pulse 21 determines that the rotor has rotated, only the correction pulse 23 is output, and the stabilization pulse 22. The second detection pulse 24 is output immediately. The figure is opposite to Fig. 8 and shows the case where the Kffi motion is insufficient to rotate the rotor. In this case, the detection pulse 22 is output to prevent rotation. In order to determine this, a correction pulse 25 is output, the rotor rotates 1800 times, and normal hand movement is ensured. FIG. 10 shows a case where the output torque by the drive pulse 2o and the load torque are exactly balanced and stop at the neutral point of I, VIA, e-90'', which is a so-called intermediate stop. Conventional.

If this intermediate stop occurs forever, the movement of the hands will be delayed.In Jijyu, this problem is solved by providing a stabilizing pulse 22 after the first detection pulse. That is, in the case where the rotor remains still at the neutral point of σ-90° even after the first detection pulse 21 is output as shown in FIG. The stabilizing pulse 22 tends to pull the rotor back to a static stable point at θ-o0.

When the rotor is pulled back to a# of -sw Q @ by the stabilizing pulse, the second detection pulse determines that the rotor is not rotating, so a second correction pulse 25 is output. Since this correction pulse is set to obtain sufficient output torque, the rotor will always rotate and the a-1Bo
Therefore, by preparing a stabilizing pulse after the first detection pulse as in the present invention, the problem that caused a delay of several seconds in the conventional case can be solved. This makes it possible to ensure absolute reliability of hand movement.

Next, regarding the direction in which the stabilizing pulse is issued.

1lIi#l There are two ways to think of it, one is to output the force in the same direction as Hals, and the other is to output the force in the opposite direction as in the present invention, but according to my experience, the force in the opposite direction as in the present invention is overwhelmingly effective. It has been confirmed that It has been shown that a stabilizing pulse, which is narrower than a square pulse, can pull the rotor back to a static point of stability. This is because when an intermediate stop occurs, the load on one wheel train is smaller if the rotor is pulled back rather than in the direction in which it is rotating, and also because the S potential curve is more likely to cause the rotor to rotate. Possible reasons include that the direction in which the object is pulled back is asymmetrical with the direction in which it is attempted to be pulled back. In any case, it is more effective to output the stabilizing pulse in the opposite direction to the direction of the drive pulse, as suggested by this author, for intermediate stops.

In the present invention, since a stabilizing pulse is provided in addition to the first and second detection pulses, there is a concern that the current consumption will increase.
CL 56 m5ec& α the pulse width of the stabilizing pulse
When set to 24m5ec, according to experiments, the average current consumption by the first and second detection pulses is 14nA each & the average current consumption by the stabilization pulse is 10nm5 total, which is very small. There is no need to worry about the battery life being affected by this.

In the explanation up to now, it has been assumed that the stabilizing pulse, which is the core of the present invention, is singular, but as shown in an example in Fig. 11,
Stabilization Nokurunu 28,2? and apply several pieces l1
Even if the first method is implemented, the effect of the present invention will not be changed in any way, and the second method will be beyond the scope of the present invention.

Furthermore, the second detection bulk may be set to one of the next driving pulses 7.

As explained above, according to the present invention, after the first detection pulse, a stabilizing pulse for preventing an intermediate stop is applied in the force direction opposite to the driving pulse.

The occurrence of intermediate stoppages, which conventionally caused delays in hand movement, can be eliminated, and absolute reliability in hand movement can be ensured. In addition, since the width of the stabilizing bulk only needs to be minute, there is no need to worry about an increase in current consumption due to the addition of a stabilizing pulse. It is extremely practical when applied to analog electronic watches.

[Brief explanation of drawings]

All! 1 Figure U Step-mo of analog electronic clock!
Figure 2 shows the conventional step motor drive waveform. Fig. 5 shows a conventional step motor aNAs waveform with a pulse width control function, Figs. Figures 8, 9, and 10 showing the voltage waveforms to be applied are low! FIG. 11 is a diagram showing the keratin displacement and the voltage waveform applied to the coil, and FIG. 11 is a diagram showing the voltage waveform applied to the coil according to another embodiment of the present invention. 1... Coil 2... Rotor S... Stator 4-a, 4-b... Outer notch S-a, 5-b... Inner notch 6.6'... Drive pulse 7. 71.-Detection pulse 8.8'-Correction pulse? - Rotor 10... Stator 11-a
, 1l-b-inner notch 12-a, j 2-b-outer notch 15-magnetic flux 14-a, 14-b--magnetic flux 15 due to rotor magnet
...Magnetic flux 16-a, 16-b due to detection pulse = Magnetic flux 18- due to rotor magnet
a, 18-b-Magnetic flux due to rotor magnet 20.20'・-
Drive pulses 21.21', 27.27'... First detection pulses 22.22', 28.28', 29.29'...
Stabilizing pulses 25.25', 50.30'... First correction pulses 24.24', 51.517... Second detection pulses 25.25', 52.52'... Second 〇Correction pulse mushroom 60 e Kudzu S Figure 89 10 figures in a circle

Claims (1)

[Claims] (1) In an analog electronic watch that determines rotation or non-rotation of the rotor based on a plurality of detection pulses after application of a drive pulse and controls the width of the drive pulse, the first detection pulse is If it is determined that the rotation is occurring, the intermediate upper tb is detected after the first detection pulse.
When a stable Ibi pulse for stopping i is applied, t-IflJg
An analog electronic clock. (2) The analog electronic timepiece according to claim 1, wherein a second detection pulse is further provided after the stabilization pulse. (5) The first detection pulse and the second detection pulse are in the same direction as the previous drive pulse, and the stabilization pulse is in the opposite direction to the direction of the Ill@ drive pulse. Claim 1: The analog electronic clock described in paragraph 2.