JPS6193976A - Electronic timepiece - Google Patents

Abstract

PURPOSE:To reduce the electric power consumption of a pulse motor and to make possible the instantaneous correction of a malfunction during the driving with the low electric power consumption by changing the driving power in accordance with the magnitude of load. CONSTITUTION:The load is detected by a load detecting circuit 29 based on the induced current waveform after impression of a driving pulse to the pulse motor 28 and a control circuit 30 controls the driving of the motor 28 in accordance with the detected load condition. The narrow driving pulse is supplied in this case by presuming the ordinary state and the stage of no load on the motor 28. The magnitude of the load is always detected by the induced current waveform after driving and the driving at the first narrow driving pulse width is continued when the load is small. The driving is executed with the wide driving pulse width for a specified time from the next driving when the load increases near to the limit of the driving at the narrow driving pulse width and thereafter the driving is returned to the driving with the narrow driving pulse width.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic timepiece, and more particularly to a drive system for a pulse motor as an electric mechanical gradual change mechanism. An object of the present invention is to reduce the power consumption of such a PAL 2 motor. Another object of the present invention is to detect or anticipate and instantly correct malfunctions that may occur during low power consumption driving.
Another object of the present invention is to provide a control system in which erroneous creation or correction in the external operation of a timepiece, such as the operation of the second hand, is not detected.

Since the so-called quartz wristwatch, which uses a quartz oscillator as a time standard oscillator, was put into practical use, it has become widely popular due to its high precision and reliability. During that time, technological innovations in crystal wristwatches have been remarkable, and their power consumption, which initially required 20-plus microwatts, can now be achieved with around 5 microwatts.

However, the current erasure! Looking at the breakdown of the power of 5 μW, it is 1.5 to 2 μW due to the 1-frequency division circuit of the crystal oscillator, and 3 to 3.5 μW for 1 pulse Tanabata, and a kana cyan balance is noticeable. Since the power consumption of the conversion mechanism accounts for 60 to 70% of the total power consumption, reducing the power consumption of this pulse motor is likely to be effective in further reducing power consumption in the future. However, the conversion efficiency of current pulse motors is very high, and an air knob with an efficiency higher than this is quite high.
It is difficult. However, conventional pulse motors have been designed to operate satisfactorily even under the worst conditions due to requirements such as an load-resistant mechanism such as a calendar mechanism, resistance to environments such as temperature and magnetism, and resistance to external disturbances such as vibration and shock. For this reason, the motor was required to have the ability to withstand a certain load under certain driving conditions, but in reality, a watch body only experiences this kind of load for about 4 to 5 hours in a day. In other words, if the watch body is always in a no-load state, the motor mechanism does not need to be designed to withstand such a large load, and in that case, the power consumption will also be reduced by 9. However, since watches are exposed to harsh environments for short periods of time, in order to guarantee this, it was necessary to use a pulse motor that can supply a large amount of power and obtain a large output.

The present invention corrects the above-mentioned irrationality by driving the pulse motor with less power when the load is small, and with high power when the load is large, and greatly reduces the power consumed by the pulse motor. It is intended to reduce Moreover, this type of drive system is constructed using reliable all-electronic means without including mechanical contacts, and the type of motor,
This realizes stable drive that can cope with variations caused by mass production.

The present invention will be explained below.

Figure 1 shows an example of a pulse motor for an electronic wristwatch. In the figure, 1 is a permanent magnet rotor magnetized to two poles, and stators 2 and 3 are arranged facing each other with rotor 1 in between. However, these stators 2 and 3 are connected to each other by a yoke 5 around which a coil 4 is wound to form a set of stators.

The stators 2 and 3 are connected to the arcuate portion 2 of the stator 213 relative to the center of the rotor 1 so that the rotor 1 can rotate in a fixed direction.
a and 3a are eccentric, and when the rotor 1 is at rest, the magnetic & (N
and S) the position is shifted to one side of the stator 2°3. This type of pulse motor has been in practical use for some time, and has been driven by a circuit block as shown in FIG. 10 is a crystal oscillator, which is driven by an oscillation circuit 11, whose frequency is determined by a frequency divider 1.
2, and the waveform shaper 15 shapes two pulses having an appropriate time width and different 18CP phases at an appropriate time interval.

As an example, a pulse of 7.8 msec every 2'' will be considered and explained below.
．． 15, and its output is sent to terminals 4a and 4b of coil 4.
supply to. FIG. 3 is a detailed diagram of a part of this driver. When a signal 18 is applied to the input terminal 16 of one inverter 140, a current flows as shown by an arrow 19, and conversely, a current flows to the input terminal 17 of the other inverter 15. When a similar signal is applied, a current flows in a route symmetrical to arrow 19. That is, by alternately applying signals to the input terminals 16 and 17 of both inverters, the current flowing through the coil 4 can be alternately reversed. Specifically, the current flowing through the coil 4 can be alternately reversed every second.
With such a drive circuit that can flow a current of 8mθθC to the coil 4, the stators 2 and 5VC of the step motor shown in Fig. 1 alternately generate N and S poles, and the rotor 1 is repelled and attracted by the magnetic poles of the rotor 1. 1 can be rotated by 180 degrees. The rotation of the rotor 1 is transmitted to the fourth honor wheel 7 via the intermediate wheel 6, and further to the third honor wheel 8,
2nd car9. Further, although not shown, the signal is transmitted to a cylinder pinion, an hour wheel, a calendar mechanism, and operates indicating mechanisms such as an hour hand, a minute hand, a second hand, and a calendar.

The pulse motor shown in FIG. 1 operates in principle as explained above, and has been used as a conversion mechanism for electronic wristwatches.

In the drive circuit shown in Fig. 5, when a high level signal is applied to the terminal 17 and a signal 18 is applied to the terminal 16, and a current flows as shown by the arrow 19, a voltage based on the bidynamic current is applied to the transistor 15 due to the channel impedance. A drop occurs and a signal waveform corresponding to this current can be detected at terminal 4'b. The current waveform is as shown in FIG. 4, for example. In Figure 4, section A is the driving section, which in this case is 7.8m5.
sc.

The current flowing in this section A is the current consumed by driving the motor. The reason why the current waveform in section A shows a complicated shape as shown in the figure is that in addition to the current generated due to the voltage applied by the drive circuit, an induced current is superimposed on the coil due to the rotation of the driven rotor. It's for a reason. Section B is the section after the driving pulse is applied, and the rotor rotates due to inertia and vibrates until it stops at a stable position.At this time, this section is the period after the driving pulse is applied.
Channel MO8) Since the transistor is ON, the rotor τ is connected to the loop between coil 4 and this transistor.
An induced current flows to the coil 4 according to the movement of the coil. This is why the waveform in section B in FIG. 4 is pulsating. Therefore, the shape of this driving current waveform and the induced current waveform after driving can almost correspond to the rotational position of the rotor.

Now, waveform 20 and waveform 20' in FIG. 4 are a series of waveforms, and this is when the load on the rotor is very small. Waveform 22 and waveform 22' are also a series of waveforms, and in this case, the load on the rotor is large and close to the operating limit of the rotor, and waveform 21° and waveform 21' are at a load of approximately 1/2 of the maximum allowable load. This is the case when multiplied by . If you carefully observe the current waveform when the load is changed in this way, you will see that the waveform extends to the right as the load increases.

This is because the rotation of the rotor slows down as the load increases, and it has been experimentally confirmed that the rotor vibration frequency and amplitude become low until it stops at a stable position. Considering this phenomenon in reverse, if the load on the rotor is always in a no-load state, the drive pulse width is 7.8
It is understood that driving with a short pulse width is possible when msec is used. In fact, even if the pulse width is shortened, the motor still operates and the output torque decreases. This situation is shown in FIG. FIG. 5 shows the output torque characteristics and power consumption characteristics when the drive pulse width is changed. The aforementioned drive pulse li 78 m sec corresponds to P2 in this figure. In other words, the output torque is T2 with a pulse width of P2.
This output torque T2, which will have a power consumption of 2 min, is set so as to be able to sufficiently withstand the load encountered by the watch body, as described above. However, the load on the rotor is small7
,ignored...? Ah, I, one, 6, 22 (
may be small, the driving pulse width can be shortened, and therefore power consumption can be reduced. For example, if the drive is performed with a pulse width of P, the output torque can be increased and the power consumption can be reduced.The present invention focuses on this point, and detects the load applied to the rotor K. When the load is small, it is driven with a narrow pulse width, and when a large load is applied, it is driven with a wide pulse width, which is a rational way to reduce power consumption. As mentioned before, the overwhelming majority of people are in a no-load state, so the effect of reducing power consumption is very large.

For example, as shown in Fig. 5, when there is no load (20 hours), it is driven with a pulse width of Pl, and when it is loaded (4 hours), it is driven with a pulse width of P2,
Assuming that 1/work = 172, the average power consumption is as follows.Compared to the conventional method in which the drive is always driven with a pulse width of P2, the power consumption is 60 inches or less, which is a significant reduction in power consumption.

By the way, although it was briefly mentioned above that "load is detected...", it goes without saying that this method of detecting load is a major point of the present invention. Next, a method for detecting this load will be described. Looking at the current waveform flowing through the coil in FIG. 4, it can be seen that the current waveform changes as the load increases. That is, in drive section A, the positions of maximum and minimum shift to the right as the load increases. The magnitude of the load can be determined by focusing on this point, but the amount of change in this waveform is extremely small, making it difficult to absorb variations in mass production, and requires extremely delicate control.

Therefore, the present invention focused on section B after application of the drive pulse. Also in this section B, as the load increases, for example, the point where the minimum value is first shifted to the right. Moreover, compared to the amount of change in the waveform in section A, the amount of change can be obtained several times as much. Therefore, it is easier to detect the magnitude of the load based on the induced current waveform in this section B than in the above-mentioned section A, and the reliability is also higher. This phenomenon is the same when the drive pulse width is shortened, and the situation is shown in Figure 6.The drive shown in Figure 6 has a narrower drive pulse width than the one in Figure 4, so it can withstand small loads. However, the relationship between the drive current waveform 23 at no load, the induced current waveform 23' after driving, and the drive current waveform 24 at the operating limit load and the induced current waveform 24 after driving is shown in Figure 4. The same is true. The load is detected by the method described above, but the configuration of the present invention normally drives the motor with a narrow drive pulse assuming no load, and always detects the load size from the induced current waveform after driving. When is small, driving continues with the initial narrow driving pulse width. If the load increases and approaches the limit of driving with a narrow drive pulse width, the next drive will be driven with a wider drive pulse width for a certain period of time, and then the drive will be returned to the original narrow drive pulse width. .

The present invention generally has such a configuration, and will be explained in more detail with reference to the block diagram of FIG. 7.

FIG. 7 is a block diagram showing the configuration of the present invention, and 25
2 is a time standard oscillator, 26 is a circuit including an oscillation circuit, 1 frequency division circuit, etc., 27 is a pulse motor drive circuit, and 2B is a pulse motor.The configuration up to this point is the same as that of a conventional electronic wristwatch. 29 is a load detection circuit that detects the load based on the induced current waveform after application of the drive pulse as explained in FIGS. 4 and 6. 30 is a control circuit that detects the load according to the state of the load detected by the load detection circuit 29 This is a circuit that controls the drive of the pulse motor 28, and normally controls to supply a narrow M-motion pulse when no load is applied, and a wide driving pulse when a load is applied.

This control system will be explained with reference to FIG. Figure 8 is MIM
This figure shows the J Hull Pulse state, and this state, which is supplied as described in the previous pulse motor section, is the pulse 31.5
Shown as shown in 2. Pulses 31,32 are narrow pulse widths under no-load conditions. After applying pulses 31 and 32, the detection circuit of FIG. 7 detects a load condition, which is either no load or a small load condition. That is, since the load detection after pulse 31 is determined to be no load, the next pulse 32 is made with a narrow pulse width.
Since the load detection after pulse 32 was also determined to be no load, the next pulse 55 also has a narrow pulse width. In load detection after pulse 33, it was determined that the vehicle was in a loaded state.

In this case, after pulse 33, after several IQrnaea, K, wide
; a second drive pulse 34 having the same pulse width is applied with the same polarity as the pulse 33 (ie, the same current direction).

For the subsequent constant number of pulses, wide pulse width pulses 35, 36 are applied, and then the initial narrow pulse width pulses 57, 58, etc. are applied again. pulse 33
To explain the relationship between the pulse 34 and the pulse 34, when it is detected that the load is large due to the drive of the pulse 35, several tens of m s e
After c, a pulse 34 with a wide pulse width is applied. This is because the load is detected after pulse 33 and it is determined that the load is large, but it is difficult to determine whether the rotor has operated at this time because the induced current waveform in Figure 6 shifts to the right as the load increases and attenuates. do. When the rotor does not operate, no induced current is generated, but it is difficult to distinguish this from the situation where the rotor barely operates when the load is close to its limit. If the load increases gradually,
Even if it is determined that the load is large, the rotor is operating at the pulse 33 at that time, and the rotor does not operate at the pulse 35 if the load suddenly becomes too large to be driven with a narrow pulse width.

It is difficult to distinguish between the two. Therefore, it is easy to set the load detection after pulse application so that there is some margin. In this configuration, 34t pulses are applied. When the rotor is operated by the pulse 33, the pulse 34 is a pulse in the same direction as the pulse 33, so this pulse 34 is a pulse in the opposite phase, and the rotor does not rotate. Also, if the rotor does not operate with pulse 33, it will be driven with pulse 34. At this time, the rotor will be driven with a delay of several tens of meters, but this will not be recognized by the eye as an operation of the second hand. There is no need to worry about unsightliness caused by this. Then, after detecting the load, a wide pulse width pulse 55. The reason why 36 was configured to continue for a certain number of pulses is that the largest load on the rotor is the calendar mechanism, and this continues for 3 to 4 hours, so if you immediately return to a narrow pulse width, it will be judged as being under load again. However, if this is repeated, two pulses will be supplied for each operation, increasing power consumption and eliminating the significance of reducing power consumption. In addition, the load placed on the rotor is not only due to the calendar mechanism, but also includes one-off loads such as magnetic fields, low temperatures, and disturbances.

In such a case, the number of continuous pulses with a wide pulse width is preferably small. Taking such phenomena into consideration, the number of continuous pulses is set to several tens of seconds to several tens of minutes. This is desirable.

The configuration of the present invention has been described above. Next, specific embodiments of the present invention will be described. FIG. 9 is an example of a load detection circuit and a drive pulse control circuit of a timepiece according to the present invention. 9th
In the figure, 25 is an oscillation circuit, 26 is a frequency dividing circuit, 2 is a motor and drive circuit, and 29 is a motor load state detection circuit. Hereinafter, the circuit elements will be explained one by one.

The NAND GAT% output of No. 39 is a clock for creating a narrow pulse when driving the motor in a no-load state, and generates a clock pulse delayed by 5 m5 ec with respect to the falling edge of a 1 second signal, for example. At this time delay 7 lip 70
The knob 42 delays the input one-second signal by 5ms+30 and outputs it, and a narrow pulse of 5msecg is generated at the output of the gate 46. Flip 70 tube 44 is 128Hz
44 with 70 delay flips with clock input
The output of is delayed by 7.8 m sec with respect to the input 1 second signal. Therefore, a pulse of lf3mgec@ is obtained at the output of the gate 47, and this is used as a wide pulse for driving when a load is applied. The gate 40 is a clock for generating a pulse for determining the no-load state and the loaded state for the time until the minimum portion of the current waveform generated by the rotor operation appears immediately after the application of the drive pulse, and is 42.44. By similar operation, judgment reference pulses are obtained at the outputs 43 and 48.

58 in FIG. 10 corresponds to the output narrow pulse of the gate 46 (59 is the criterion for determining the output of the gate 48). -f-) 711 is a correction pulse generation circuit with a wide pulse width of zF3 msec, for example! +0m5ec late. FIG. 10 661C shows an example. The gate 410 input terminal 57 receives a correction signal, which will be described later, and only when the correction signal becomes
A correction pulse is generated at the output of and supplied to the subsequent stage. The inputs of the controllers 39, 40, and 41 separate the pulses to the drive inverter 14, 15,
This is a circuit that outputs signals alternately every second. The gate 50 has a correction pulse of 41 when the counter 5.2 is zero.
When a signal is issued to the output terminal of , one count input is sent to one counter 52. Once the counter 52 starts counting, the gate 50 remains in the OFF' state until all outputs of the counter 52 return to zero. When the gate 52 enters a counting state by the output of the gate 50, the gate 51 opens and continues to send a 2-second signal as a count signal to the gate 52 until all outputs of the gate 52 become zero.

As mentioned above, the counter 52 is set appropriately between several tens of seconds and several tens of minutes, and after detecting that the motor is in a loaded state, outputs a wide pulse drive signal for the above-mentioned time width. The timer goes off to continue. Reference numeral 47 uses the output of the counter 52 as a gate input, and outputs a wide pulse to the subsequent stage while 52 is in the counting state.

Block 29 in FIG. 9 is an example of a circuit that detects the motor load from the operating state of the motor after application of the drive pulse. 55.54 is a transmission gate,
The outputs of the drive inverters i4 and i15 are alternately selected according to the drive signal.

The outputs of 53 and 54 are multiplied and input to a differential amplifier 55 via a capacitor. Of the 53.54 output signals,
The waveforms in the no-load state and the waveforms in the loaded state are shown as 10th waveforms, respectively.
Shown in Figure 60.61. The differential becomes a rectangular wave that is inverted at each peak, and a signal of 62 for 60 and 64 for 61 is obtained.The output of the inverter is delayed by the CB timer circuit and input to one of the inputs of the Nant gate 56. By using the intermediate output of the 21-D inverter as the other input of the Nant gate 56, the signals 65 and 6 in FIG.
Get 5. Signal 6ji corresponds to output waveform 60, and signal 65
corresponds to the output waveform 61. Comparing the output waveform 60.61 and the signal 65.65, it is clear that the pulse of the signal 62.65 indicates a predetermined peak position of the output inverse shape. The load state is detected by determining whether the pulse position of this signal 65.65 is inside or outside the above-mentioned criterion S pulse 59, and in the former case, it is determined that it is a no-load state,
The bite person is determined to be in a loaded state. Therefore, the signal 65 indicates the no-load state B, and the signal 65 indicates the loaded state.

Note that the output signals 65 and 65 of the Nandt gates output pulses in the negative direction.

Next, the correction pulse generating means will be described. gate 10
4 is the load detection signal that is the output of the gate 56, and the gate 4
The judgment standard Hals signal No. 59 which becomes the output of 8 and the 1 second signal which becomes the output of the delay flip-flop 44 are
The output signal of the delay flip-flop 44 is input to the gate 104 as a mask signal for determining the detectable period.

With the above configuration, the detection signal when there is no load (Fig. 10, 6
59 passes through the gate 104, but the performance signal 65 when there is no cargo is prohibited. Line 57 is connected to gate 107 and 1
It is the output of the flip 70 tube formed by 08,
Gates 106 and 105 form the set input. The 1-second signal input to +06 determines the desired set state of the flip-flop, and the output 57 must be set to H in the load detection state.In this state, no load state is detected. When the signal passes through +04, it passes through gates 105 and 106, resets the flip-flop, and puts output 57 in the L state. However, when the load is heavy, the reset signal is not input, so the output 57 is high.
It remains set to . If the output 57 remains high, the gate 41 that generates the correction pulse will pass through the correction pulse, so the gate 48 or 4 for the drive circuit will
A correction pulse is supplied to the coil through 9. The other input of the ter) 105 receives a signal which prohibits the passage of the detection signal at the same time as the counter 52 starts operating. At the same time as the setting, a pulse having the same polarity as the drive pulse at which the heavy load state was detected is supplied. That is, HAND gates 90 and 91 and 1iAND
A 2 second signal is applied to the gates 92 and 93 as a gate signal, and in particular, the HAND gates 90 and 91 are connected to the input gate 94.
92 and 93, a 2 second signal of opposite polarity to that of the HAND gates 92 and 93 is applied.

As a result, the normal drive pulse that has passed through the OR gate 95 passes alternately through the MD gate 90 and the HAND gate 92 every second, and is supplied to the drive circuit. Further, when a heavy load condition is detected from the induced current generated in the coil after application of the drive pulse, the correction pulse 66 is outputted with a delay of several tens of m5ec from the drive pulse, as described above.

The correction pulse is input to HAND gates 91 and 93, which in turn are input to gates 90 and 9, respectively.
Since the two gate signals are shared, the correction pulse is supplied to the drive circuit as a pulse having the same polarity as the drive pulse. As a result, for the case of waveform 61, the correction pulse 6
6 is subsequently applied, and 66 completes the rotation of the rotor. However, as described above, this also includes the case where the rotation of the rotor is completed before 66 is applied. Correction pulse 66 is also applied to counter 52 via gate 50.
, the gate 51 is turned on and the gate 52 is turned on. Thereafter, the gate 47 is kept in the ON state for a certain period of time to continue supplying the wide pulse drive signal. While the wide pulse is being supplied, 57 is in the LOW state and no correction pulse is output.

This is because the motor is considered to have sufficient output torque during wide pulse driving.

As described above, in this embodiment, the waveform shaping circuit of the normal driving nozzle is surrounded by a frame 99 in FIG.
For a drive pulse with a 5ec pulse width, a delay flip-flop 42, a gate 39, a gate 46, and an inverter 96 form a delay flip-flop, and a delay flip-flop with a 128Hz clock signal is used for a drive pulse with a 7, 8+n5ec pulse width. 44, a gate 47, and an inverter 96. In addition, a load detection circuit 29 shown in diagram t59 is used as a load detection circuit, and a load state determination circuit is surrounded by a frame 97 in FIG. Gates 107 and 108 are used.

The correction pulse generation circuit is surrounded by a frame 98 in the diagram F59, and includes a gate 41 that receives the output 57 of the flip-flop as an input, and supplies the output of the gate 41 to the drive circuit as a correction pulse having the same polarity as the drive pulse. 91.93.

As a peak detection circuit, in addition to 55 differential amplifier circuits,
Various methods are possible. FIG. 18 is a block diagram of a peak detection circuit using a delay circuit. In the figure, 53 and 54 are transmission gates, 80 is a pIS9 general amplifier in place of the one shown in FIG. 55, 81 is a delay circuit, and 82 is 80 and 81.
This is a comparator that inputs the output of An example of amplifier β0 is 1
The motor drive detection waveforms 23, 24, etc. shown in Fig. s13 or Fig. 14 are signals of approximately allV to several tens of mV generated substantially near the power supply level, so the resistor 66
The voltage is divided by 67 degrees and converted to the input operating level of the amplifier. A waveform 76 in FIG. 16 appears at the terminal 68.

FIG. 14 shows a circuit improved from FIG. 13, with 6 resistors.
In place of MO 7: MO8) A transistor is inserted and a return circuit is provided to control the channel impedance of the transistor 69 so that the amplifier input level becomes the operating level.
Block 70 is a circuit that detects the output level. 1st
FIG. 5 shows a simple embodiment of the delay circuit 81, with 71.7
Transmission gates 1-172 and 74 are load capacitors. In this case, the input signal 76 at terminal 68 is delayed as 77 at the output terminal.

FIG. 17 schematically represents this waveform. Input signal 76 is transmitted to capacitor 72 by transmission gate 71, and the terminal voltage waveform of 72 becomes 79. Furthermore, a waveform 77 appears at the output terminal 75 by the transmission gate 75. Comparator 82 receives waveform 7
When 6 and 77 are input, a rectangular signal shown at 78 is output.

As a delay circuit, the one shown in FIG. 15 is suitable, but since the input signal frequency is relatively low, a bucket brigade data transfer element or the like is also suitable. Fig. 19 shows the detected current waveform when a DC magnetic field is applied in the direction of the coil of a pulse motor. 83 is a case where the directions of the magnetic field induced in the motor inner core by an external magnetic field and the driving magnetic field are opposite to each other, and 84 is a case where both magnetic fields are in the same direction.

Waveforms 95 and 86 at 85.84 and 95.86 have zero external magnetic field, and can be considered to be almost the same waveform. 87 and 88 are waveforms when the external magnetic field is 40 Gauss. According to the waveform, the operation in the direction of 83 will cause the external magnetic field to become stronger, making it difficult to operate.
It shows the same characteristics as the operation when the load becomes large. Therefore, the timepiece circuit according to the present invention operates effectively against the influence of external magnetic fields, and it has been experimentally confirmed that the strength against external magnetic fields is no different from that of conventional timepieces. In the case of 87 in FIG. 19, since the waveform's pole and minimum positions appear after the determination reference pulse, a correction signal indicated by 87' is added. From the above explanation, it can be easily inferred that the present invention has an effective effect on impact resistance as well.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described here, and various improvements, changes, and applications are possible. For example, the pulse motor is not limited to the pulse motor described here. A conversion mechanism other than a motor may be used, and even a pulse motor shown in Figure 11 can be realized with the same configuration.

In the pulse motor shown in Fig. 11, the rotor 100 is made of a permanent magnet, and the stator 101 is an integral type with no gap, unlike the stator 101 in Fig. 1, and notches 102 and 105 are formed for determining the static position of the rotor. has been done.

104 is a drive coil.

Since such a pulse motor is connected to the stator 101, the induced current after driving is slightly different from that in FIGS. 4 and 6, as shown in FIG. 12.

However, the relationship between the waveforms 105 and 105' during no-load and the waveforms 106 and 106' during load are basically the same, and the rotor load state is detected by the induced current generated in the same coil, and the load detection circuit When a positive load condition is detected by the determination circuit, the configuration continuously outputs a correction pulse that has a pulse width larger than the drive pulse and has the same polarity as the drive pulse.Pulse 1 of the normal drive pulse
11i can be reduced to reduce power consumption, and reliable operation of the pulse motor can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a pulse motor of an electronic wristwatch according to the present invention. 2 and 3 are diagrams showing the conventional circuit configuration, and FIG. 4 is a diagram showing the T4. A diagram showing the shape of a stream. FIG. 5 is a diagram showing the relationship between the output torque and the extinguishing side force with respect to the drive pulse width of the pulse motor. Figure 6 shows coil 1 when the motor is driven with a pulse width narrower than the conventional drive pulse. It is a flow waveform diagram. FIG. 7 is a diagram showing a circuit block of an uninvented clock. Figure 8 shows a motor using the circuit according to the present invention! E! I] This is an example of a pulse time chart. Figure 9 is I! The figure which shows one specific example of the block circuit of figure J8. FIG. 10 is an example of a time chart of the load detection section in FIG. 9. FIG. 11 is a diagram showing an example of a pulse motor of an electronic wristwatch according to the present invention. FIG. 12 is a coil current waveform diagram when the pulse motor of FIG. 11 is driven with narrow pulses. FIGS. 13 to 18 are diagrams showing other examples of the load detection section in FIG. 9. FIG. 19 is a diagram showing changes in the coil current waveform when a flowing magnetic field is applied to the electronic wristwatch according to the present invention. 25... Oscillation circuit, 26... Frequency dividing circuit, 27...
Drive circuit, 28...Motor, 29...Motor load detection judgment circuit, 30...Control circuit, 31-33...
・Narrow pulse drive signal, 34... Correction signal, 35...
Wide pulse drive signal, 59...Load judgment reference pulse, 6
0...No-load detection signal, 61...Load detection (
No. 6, 1 or more

Claims (1)

[Claims] a time standard oscillator, a frequency divider that divides the output signal of the time standard oscillator, a waveform shaping circuit that forms a drive pulse by the output of the frequency divider, a drive circuit operated by the drive pulse, a coil and a permanent In the electronic timepiece comprising a magnetic rotor and a stator and a pulse motor driven by the drive circuit, a load detection circuit detects an induced current generated in the coil after application of a drive current as a rotor load; a determination circuit that determines a rotor load condition from an output of the circuit, and is controlled by the determination circuit, and when the determination circuit determines a heavy load condition, generates a correction pulse having a pulse width larger than the drive pulse and having the same polarity as the drive pulse. An electronic clock equipped with a correction pulse generation circuit that outputs.