JP2003219695A - Apparatus and method for controlling stepping motor and clocking device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for controlling wherein power consumed in stepping motors for driving hands is further reduced and a small- sized, long-life clocking device can be realized. <P>SOLUTION: If the rotation of a rotor is not detected by a pulse SP2 for rotation detection subsequent to a first driving pulse P1, an auxiliary pulse P2 is outputted. In a predetermined number of the subsequent cycles (e.g. three cycles), a second driving pulse P11 whose effective power is greater by several steps than that of the first driving pulse P1 is outputted. By this second driving pulse P112, a step angle wherein the load is increased due to tolerance in period for a short time can be driven. When the three cycles are completed, the pulse can be returned to the first driving pulse P1 with low effective power. Therefore, the effective power of the first driving pulse can be held in a state in which the effective power is reduced to the limit, and thus power consumption can be further reduced. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor control device and control method, and more particularly to a control device and control method suitable for an electronic timepiece having low power consumption.

[0002]

2. Description of the Related Art Stepping motors are pulse motors,
It is also called a stepping motor, a stepping motor, a digital motor, or the like, and is a motor driven by a pulse signal that is widely used as an actuator of a digital control device. In recent years, small electronic devices or information devices suitable for carrying have been developed, and small and lightweight stepping motors are often used as these actuators. Typical of such electronic devices are timing devices such as electronic timepieces, time switches and chronographs. FIG. 7 shows an example of a time measuring device such as a wrist watch device using a stepping motor. This timer 9
Is provided with a stepping motor 10, a control device 20 for driving the stepping motor 10, a train wheel 50 for transmitting the movement of the stepping motor 10, and a second hand 61, a minute hand 62 and an hour hand 63 carried by the train wheel 50. There is. The stepping motor 10 is rotated by a drive coil 11 that generates a magnetic force by a drive pulse supplied from the control device 20, a stator 12 that is excited by the drive coil 11, and a magnetic field that is excited inside the stator 12. A PM-type (permanent magnet rotation type) stepping motor 1 including a rotor 13, the rotor 13 including a disk-shaped two-pole permanent magnet
It is 0. The stator 12 is provided with a magnetic saturation part 17 so that different magnetic poles are generated in the respective phases (poles) 15 and 16 around the rotor 13 by the magnetic force generated in the drive coil 11. Further, in order to define the rotating direction of the rotor 13, an inner notch 18 is provided at an appropriate position on the inner circumference of the stator 12 so as to generate a cogging torque and stop the rotor 13 at an appropriate position. ing.

The rotation of the rotor 13 of the stepping motor 10 is the fifth wheel 5 meshed with the rotor 13 via a pinion.
1st, 4th wheel 52, 3rd wheel 53, 2nd wheel 54, behind the wheel 5
It is transmitted to each needle by a train wheel 50 composed of 5 and hour wheel 56. The second hand 61 is connected to the shaft of the fourth wheel & pinion 52, the minute hand 62 is connected to the second wheel & pinion 54, and the hour hand 63 is further connected to the hour wheel 56, which are linked with the rotation of the rotor 13. The time is displayed by each hand of. It is of course possible to connect a transmission system or the like (not shown) for displaying the date and the like to the train wheel 50.

In this clocking device 9, in order to display the time by the rotation of the stepping motor 10, the stepping motor 10 counts (clocks) a signal having a reference frequency and is supplied with a drive pulse periodically. The control device 20 of this example for controlling the stepping motor 10 includes a pulse synthesizing circuit 22 for generating a reference pulse of a reference frequency and a pulse signal having a different pulse width and timing by using a reference oscillation source 21 such as a crystal oscillator. A control circuit 23 for controlling the stepping motor 10 based on various pulse signals supplied from the synthesizing circuit 22 is provided. Further, the control circuit 23 includes a drive control circuit 24 that controls a drive circuit described later and a detection circuit 25 that detects rotation. The drive control circuit 24 supplies a drive pulse for driving the drive rotor 13 of the stepping motor 10 to the drive coil 11 to the drive coil 11 via the drive circuit, and a drive pulse following the drive pulse, the drive rotor 1
3, a rotation detection pulse supply unit 24b for outputting a rotation detection pulse for inducing an induced voltage for rotation detection, and an auxiliary pulse having a larger effective power than the drive pulse when the drive rotor 13 does not rotate. Auxiliary pulse supply unit 24c for degaussing, a degaussing pulse supply unit 24d for outputting a degaussing pulse having a polarity different from that of the auxiliary pulse for degaussing following the auxiliary pulse, and a level for adjusting the effective power of the drive pulse. The adjusting unit 24e is provided. Further, the detection circuit 25 compares the induced voltage for rotation detection obtained by the rotation detection pulse with a set value to detect the presence or absence of rotation, and can feed back the result to the drive control circuit 24.

A drive circuit 3 for supplying various drive pulses to the stepping motor 10 under the control of the drive control circuit 24.
0 is the n-channel MOS 33a and p connected in series
Channel MOS 32a and n channel MOS3
A bridge circuit composed of 3b and a p-channel MOS 32b is provided so that the electric power supplied from the battery 41 to the stepping motor 10 can be controlled. Furthermore, p-channel MOS 32a
And 32b and rotation detecting resistors 35a and 35b respectively connected in parallel, and these resistors 35a and 3b.
Sampling p-channel MOSs 34a and 34b for supplying a chopper pulse to 5b are provided. Therefore, these MOS 32a, 32b, 33a,
Drive pulses having different polarities are applied to the drive coil 11 by applying control pulses having different polarities and pulse widths to the respective gate electrodes 33b, 34a, and 34b from the pulse supply units 24a to 24e of the drive control circuit 24 at respective timings. Can be supplied, or a pulse for detecting the rotation of the rotor 13 can be supplied.

FIG. 8 is a flow chart showing the movement of the control device 20. First, in step ST1, the reference pulse for timing is counted to measure 1 second. When 1 second has elapsed, the drive pulse P1 is output under the control of the drive pulse supply unit 24a in step ST2. Subsequently, in step ST3, the rotation detection pulse SP2 is output under the control of the rotation detection pulse supply unit 24b, and the obtained voltage is compared with the set value by the detection circuit 25 to confirm the rotation of the rotor 13. If the rotation cannot be confirmed, a subroutine for surely rotating the rotor 13 using the auxiliary pulse is executed. In this subroutine, first, in step ST4, the auxiliary pulse P2 having large effective power is supplied under the control of the auxiliary pulse supply unit 24c to reliably rotate the rotor 13. When the auxiliary pulse P2 is output, in step ST5, the degaussing pulse PE is output under the control of the degaussing pulse supply unit 24d. Next, in the level adjusting unit 24e, the effective power of the drive pulse P1 output next is increased by one step. Then, when these steps are performed, the process returns to the main routine and the following processes are executed.

When the rotation of the rotor 13 is confirmed in step ST3, the counter n is incremented in step ST7 without executing the above subroutine. And
In step ST8, when the value of the counter n has not reached the first set value N0, the process returns to step ST1 and the above steps are repeated. The value of the counter n is the first set value N
When it reaches 0, the drive pulse P of constant effective power
Since 1 means that the rotor 13 has continuously rotated the first set value N0 times, the effective power of the next drive pulse P1 is lowered by one step using the level adjusting unit 24 in step ST9. Then, in step ST10, the counter n is cleared to zero to prepare for the next cycle.

FIG. 9 shows a p-channel MOS 33a and an n-channel MOS 32 for exciting the drive coil 11 with a magnetic field of one polarity in order to drive the stepping motor 10 to rotate.
a and the gates GP1, GN1 and GS1 of the p-channel MOS 34a for sampling, and the gates GP2, GN2 and GS2 of the p-channel MOS 33b, n-channel MOS 32b and the p-channel MOS 34b for sampling for exciting a magnetic field in the opposite direction. The supplied control signal is shown using a timing chart. The stepping motor control device 20 controls the stepping motor 10 of the timing device 9 in order to control the stepping motor 10.
The hand movement is performed every second, and the drive circuit 30 is cyclically supplied with a series of control signals. First,
At time t1, for example, a control signal for outputting a drive pulse P1 having a pulse width W10 is output from the drive pulse supply unit 24a of the drive control circuit 24 to the n-channel MOS 32 on the drive pole side.
It is supplied to the gate GN1 of a and the gate GP1 of the p-channel MOS 33a. Following the drive pulse P1, a drive control circuit 2 outputs a control pulse for outputting a rotation detection pulse SP2 for detecting rotation of the rotor 13 at time t2.
The rotation detection pulse supply unit 24b of No. 4 supplies the gate GP1 of the p-channel MOS 33a and the gate GS1 of the sampling MOS 34a on the drive pole side. The rotation detection pulse SP2 is a chopper pulse having a duty of about ½, and an induction current excited in the drive coil 11 when the rotor 13 rotates is detected by the rotation detection resistor 35.
The output voltage of a is obtained. And
The voltage of the rotation detecting resistor 35a is compared with a set value in the detection circuit 25 so as to determine whether or not the rotor 13 has rotated.

When the induced voltage excited by the rotation detection pulse SP2 does not reach the set value, it is determined that the rotor 13 has not rotated, and the control signal for outputting the auxiliary pulse P2 at time t3 in step ST4. Are supplied from the auxiliary pulse supply section 24c of the drive control circuit 24 to the gate GN1 of the n-channel MOS 32a and the gate GP1 of the p-channel MOS 33a on the drive pole side. The auxiliary pulse P2 is a driving pulse having a pulse width W20 having a larger effective power than the driving pulse P1 having energy enough to rotate the rotor 13 without fail. Auxiliary pulse P
When 2 is output, this is followed by step S at time t4.
At T5, a control pulse for outputting the degaussing pulse PE is supplied from the degaussing pulse supply unit 24d of the drive control circuit 24 to the gate GN2 of the n-channel MOS 32b on the opposite pole side and the gate GP2 of the p-channel MOS 33b. The degaussing pulse PE is for reducing the residual magnetic flux of the stator 12 and the drive coil 11 generated by the auxiliary pulse P2 having a large effective power, and is realized by supplying a pulse having a polarity opposite to that of the auxiliary pulse P2. is doing. By supplying the degaussing pulse PE, a series of cycles for driving the stepping motor 10 to rotate by one step angle is completed.

At time t11, which is one second after time t1, the next cycle for rotating the stepping motor 10 by one step angle is started. In this cycle, the MOS 32b, 33b and 34b on the opposite side to the previous cycle are on the drive pole side. Like the previous cycle,
First, the drive pulse P1 is output at time t11, but since the auxiliary pulse P2 was output in the previous cycle,
The drive pulse P1 whose effective power is increased by one step is selected by the level adjusting unit 24e, and for example, the drive pulse P having a pulse width W11 wider than the drive pulse of the previous cycle is selected.
1 is output at time t11. Further, when the rotation detection pulse SP2 is output at time t12 and the rotation of the rotor 13 is not detected by this, the auxiliary pulse P2 is further output at time t13, and subsequently, the degaussing pulse PE is output at time t14. To be done.

In the next cycle started at time t21, drive pulse P1 having a wider pulse width W12 is output at time t21. When the rotor 13 is rotated by the drive pulse P1 having the increased effective power, the time t
When detected by the rotation detection pulse SP2 output to 22, the cycle ends. The drive pulse P1 having the pulse width W12 is used to continuously rotate the rotor 1 a predetermined number of times N0.
When 3 rotates, in the cycle started from the next time t31, the effective power drops by one step, for example, the pulse width W
11 drive pulses P1 are output.

As described above, the level adjusting section 24e selects the drive pulse P1 having a low effective power for continuously rotating the rotor 13, and thus the power consumption is low and the hand movement is accurate. By doing so, it is possible to provide a small, thin, and long-life timekeeping device.

[0013]

In recent years, a timepiece device such as a wristwatch device has a smaller battery space for further miniaturization, and at the same time, has a longer life. Therefore, it is required to further reduce the power consumed by the stepping motor. Further, a wristwatch device or the like has been developed that has a built-in power generation device that can generate power by capturing the movement of a user's arm in the timekeeping device. It is important to reduce the power consumption of the stepping motor in such a self-powered timekeeping device because it is required to continue operating for a long time even when power generation is not performed, such as when it is left unattended. This is one of the challenges.

The power of the drive pulse for driving the stepping motor is reduced by adopting the control device or control method as described above. However, according to a further detailed study by the inventors,
In the case where the stepping motor, which was rotating with the drive pulse of almost the minimum torque, did not rotate the rotor due to a slight torque shortage and an auxiliary pulse was output, a drive pulse with a large effective power was supplied by one step in the next cycle. However, it turns out that there are many cases of insufficient torque. Therefore, once the auxiliary pulse is output, a torque shortage state continuously occurs, and in many cases, the drive pulse level-enhanced by two to three stages is output at once without the one-step level up. In such a phenomenon, when the auxiliary pulse is output following the drive pulse due to a hand movement error, the torque applied to the gears of the train wheel greatly changes, so the positional relationship between the shaft of the gear and the bearing slightly changes, It is considered that the meshing load greatly increases due to a change in the meshing position of the gears. Auxiliary pulse is output and once 2-3
When the drive pulse level is increased stepwise, if the drive pulse can be continuously driven a plurality of times, for example, N0 times in succession, the effective power of the drive pulse P1 is lowered by one step, and finally the drive pulse P1 can be continuously driven N0 times. It will return to the drive pulse of electric power. Furthermore, if there is a case where the meshing load increases during this period, the effective power of the drive pulse P1 again rises in one or two steps or more. Therefore, the rotor rotates continuously, the state of the train wheel returns to the state before the auxiliary pulse is output, and the effective power of the drive pulse P1 is the minimum necessary even when the torque required for rotation is low. The power is slightly larger than the power of, for example, about one or two steps, and still more.

Further, considering the cause of the output of the auxiliary pulse P2, it is considered that most of the cases are due to the fact that the meshing load of the train wheel is accidentally increased. That is, since the train wheel 50 that transmits the power of the stepping motor 10 to the hour hand and the like is composed of a plurality of gears,
There are cases where the meshing load periodically increases due to manufacturing tolerances or assembly tolerances of these gears.
In the control method described above, when the meshing load increases even at one step angle, the auxiliary pulse P2 is output, so that the effective power of the drive pulse P1 increases by one step. For example, in an appropriate cycle in which the train wheel operates. If there is a state in which the meshing load increases by two step angles, the effective power of the drive pulse P1 at this time increases by two steps. Further, when the wheel train is changed to the state of the train wheel by the torque of the auxiliary pulse as described above, the state where the torque is large may continue for several more steps. Therefore, in the conventional control device or control method, in spite of adopting the control method capable of supplying the drive pulse of the effective power capable of supplying the minimum torque necessary for rotating the rotor, in reality, In many cases, a driving pulse having energy several steps higher than that is always supplied.

Therefore, in the present invention, even if the timing of inefficiency occurs due to the meshing condition of the train wheel due to such auxiliary pulse or assembly tolerance, other effective timing is as low as possible effective power. It is an object of the present invention to provide a control device and a control method capable of further reducing the drive power of a stepping motor by supplying the drive pulse of. It is also an object of the present invention to provide a control method and a control device that can realize a small-sized, long-life timekeeping device and a self-power-generating timekeeping device that can continuously measure time even if left for a long time. Is one.

[0017]

Therefore, in the present invention, even when the meshing load increases due to the supply of the auxiliary pulse following the drive pulse, the rotor returns to the original state during several steps of rotation. It is often noted that the torque is low and that the meshing load is large due to the tolerance of the gears, etc., and is often limited to one or several steps. The drive pulse with a slightly higher effective power is supplied from the auxiliary pulse within a predetermined period, and then the drive pulse with the lower effective power set earlier is supplied instead of uniformly increasing the effective power of the drive pulse. I am able to do it.
That is, in the control device of the stepping motor capable of rotationally driving the multi-pole magnetized rotor in the stator having the drive coil of the present invention, the first drive pulse for driving the rotor is supplied to the drive coil. First drive means, rotation detection means for detecting whether or not the rotor has rotated by the first drive pulse, and auxiliary power having a larger effective power than the first drive pulse when rotation of the rotor cannot be detected. In addition to the auxiliary means for supplying the pulse and the level adjusting means for gradually reducing the effective power of the first drive pulse when the rotor continuously rotates for the first set number of times, after the auxiliary pulse is supplied, A second drive pulse having an effective power that is one or several steps larger than the effective power of the first drive pulse adjusted by the level adjusting means by the second set number of times is supplied. And it is provided with a motion means. In the second drive means, the effective power of the drive pulse can be controlled by changing the pulse width of the drive pulse or changing the voltage of the drive pulse.

Further, in the method of controlling a stepping motor capable of rotationally driving the multi-pole magnetized rotor of the present invention in a stator having a drive coil, a first drive pulse for driving the rotor with respect to the drive coil is provided. Supply first
Drive step, a rotation detection step of detecting whether or not the rotor has rotated by the first drive pulse, and an auxiliary pulse having a larger effective power than the first drive pulse when the rotation of the rotor cannot be detected. In addition to the auxiliary adjusting step and the level adjusting step in which the effective power of the first drive pulse is reduced stepwise when the rotor is continuously rotated for the first set number of times, A second drive step is provided for supplying the second drive pulse having an effective power that is one or several steps higher than the effective power of the first drive pulse adjusted in the level adjustment step by the set number of times 2.

By providing the second drive means or the second drive step as described above, the effective power of the first drive pulse whose effective power becomes low based on the track record of continuously rotating the rotor is not increased. It is possible to cope with a situation in which the meshing load of the train wheel is increased for some reason and a drive pulse with large effective power is required for a short time. Therefore, at the timing at which the driving pulse can be moved with a small effective power, the first driving pulse set to the minimum required energy can be supplied, and the power consumed by the stepping motor can be further reduced. Become. On the other hand, at the step angle where the load becomes large, the second drive pulse with a large effective power is output following the auxiliary pulse, so that a situation in which the auxiliary pulse that continuously increases the power consumption is continuously output is prevented. be able to.

Further, it is considered that a drive pulse having a large effective electric power is required for an extremely short period of time as the meshing load increases due to the above-mentioned causes, and is only one or several step angles. Then, after the auxiliary pulse, the demagnetizing pulse having a polarity different from that of the auxiliary pulse is supplied immediately before the next driving pulse, thereby increasing the effective electric power of the driving pulse and increasing the timing of the meshing load. It is possible to survive. That is, in the control device for a stepping motor capable of rotationally driving the multi-pole magnetized rotor of the present invention in a stator having a drive coil, a drive means for supplying a drive pulse for driving the rotor to the drive coil. And a rotation detecting means for detecting whether or not the rotor is rotated by the drive pulse, and a level for gradually reducing the effective power of the first drive pulse when the rotor is continuously rotated by the first set number of times. In addition to the adjusting means and the auxiliary means that supplies an auxiliary pulse having a larger effective power than the drive pulse when the rotation of the rotor cannot be detected, the auxiliary pulse is followed by a degaussing pulse having a polarity different from that of the auxiliary pulse. It is effective to provide a degaussing pulse supply means for supplying just before the pulse. Further, in the method of controlling a stepping motor capable of rotationally driving a multi-pole magnetized rotor in a stator having a drive coil according to the present invention, a drive step of supplying a drive pulse for driving the rotor to the drive coil A rotation detection step of detecting whether or not the rotor is rotated by the drive pulse, and a level of stepwise reducing the effective power of the first drive pulse when the rotor is continuously rotated a first set number of times. In addition to the adjustment process and the auxiliary process that supplies an auxiliary pulse with a larger effective power than the drive pulse when rotation of the rotor cannot be detected, the auxiliary pulse is followed by a degaussing pulse whose polarity is different from that of the auxiliary pulse. It is effective to provide a degaussing pulse supply step for supplying immediately before the pulse.

By providing such a degaussing pulse supply means or a degaussing pulse supply step, it is possible to supply a driving pulse having a substantially large effective power following the auxiliary pulse without increasing the effective power of the driving pulse. Therefore,
At timings other than the step angle where the meshing load is increased, it is possible to supply the drive pulse of the effective power reduced to the necessary minimum. Therefore, it is possible to provide a control device and a control method that can drive the stepping motor reliably and further reduce power consumption.

As described above, the control device of the present invention that can reliably rotate the stepping motor with low power consumption, the stepping motor that moves the clock hands by the drive pulse, and the pulse that outputs the pulse signal of a plurality of frequencies By realizing the time measuring device provided with the synthesizing means, it is possible to provide a small time measuring device having high accuracy and very small power consumption and long life. Further, by adopting the control method or the control device of the present invention in the time measuring device having the built-in power generation device, it is possible to realize a time measuring device capable of continuing the hand movement even after being left for a long time.

Further, the stepping motor control method of the present invention can be provided in the state of being stored in a computer-readable medium as a logic circuit, a control program for a microprocessor, etc., and is not limited to a timing device. It can be applied to devices that require low power consumption and high precision motor drive.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION [First Embodiment] The present invention will be described in more detail below with reference to the drawings. Figure 1
FIG. 1 shows a schematic configuration of the timing device 1 according to the first embodiment of the present invention. The timekeeping device 1 of this example drives the stepping motor 10 by the control device 20, and transmits the movement of the stepping motor 10 to the second hand 61, the minute hand 62 and the hour hand 63 via the train wheel 50 to perform the hand movement. There is. The main configurations of the stepping motor 10, the train wheel 50, and the control device 20 are the same as those described with reference to FIG. 7, and common portions are denoted by the same reference numerals and detailed description thereof will be omitted below.

The control circuit 23 employed in the control device 20 of the timing device 1 of this example also includes the drive control circuit 24 and the detection circuit 2.
It is equipped with 5. The drive control circuit 24 of this example includes a first drive pulse supply unit 24a that supplies a drive pulse P1 to the drive coil 11 via the drive circuit 30, and a rotation that supplies a pulse SP2 for rotation detection following the drive pulse. The detection pulse supply unit 24b, the auxiliary pulse supply unit 24c that supplies the auxiliary pulse P2 having a larger effective power than the drive pulse, the demagnetization pulse supply unit 24d that supplies the demagnetization pulse PE following the auxiliary pulse, and the effective drive pulse P1. A level adjusting unit 24e capable of controlling electric power and a second drive pulse supplying unit 24f capable of supplying a second drive pulse P11 having a larger effective power than the drive pulse P1 supplied from the first drive pulse supplying unit 24a. I have it. The second drive pulse supply unit 24f outputs the second drive pulse P11 whose effective power is several steps higher than the first drive pulse P1 from the auxiliary pulse P2 by a predetermined second set number (M0 times in this example). Cycle) for continuous supply.

Further, in the timer device 1 of this example, the electric power output from the battery 41 is supplied to the control device 20 via the step-up / down circuit 49.
Can be supplied to the drive circuit 30 of FIG. The step-up / step-down circuit 49 of this example is capable of performing multi-step step-up and step-down using a plurality of capacitors 49a, 49b and 49c, and the drive circuit 30 is controlled by the drive control circuit 24 of the control device 20 by the control signal φ11. The voltage supplied to can be adjusted. Further, the output voltage of the step-up / down circuit 49 is also supplied to the drive control circuit 24 by the monitor circuit φ12, so that the output voltage can be monitored. Therefore, the effective power of the first drive pulse P1 and the second drive pulse P11 can be set by the level adjuster 24e controlling the step-up / down circuit 49. As described above, in the timing device 1 of the present example, the effective power of the first drive pulse P1 and the second drive pulse P11 can be controlled by the pulse width and the voltage, and therefore the drive power can be finely controlled. , A drive pulse of electric power suitable for rotating the rotor 13 is supplied to save power.

FIG. 2 is a flow chart showing an outline of the method of controlling the stepping motor employed in the timekeeping device 1 of this embodiment. In this flowchart as well, steps similar to those of the control method described above with reference to FIG. 8 are denoted by the same reference numerals, and detailed description thereof will be omitted below. First, in step ST1, 1 second is measured for hand movement. In the control device 20 of this example, the next step ST
At 11, it is determined whether the value of the counter m of the second drive pulse P11 has reached the second set number M0. When the value of the counter m has reached the second set number of times M0, the process proceeds to step ST2 and the drive pulse P1 is controlled in the same manner as the conventional one based on the control of the first drive pulse supply unit 24a.
Is output.

On the other hand, when the counter m is equal to or less than the second set number M0, the process proceeds to step ST12 and the second drive pulse supply section 24f is replaced with the first drive pulse P1.
Drive pulse P1 having a large effective power based on the control of
1 is output. Then, in step ST13, the counter m is incremented. The timing at which the auxiliary pulse P2 is output is often in an inefficient state because the meshing condition of the train wheel is disturbed due to factors such as assembly tolerances. Further, in most cases, the step angle at which the meshing load increases due to such a cause is limited to one step or at most a few steps. Also,
Even if the state of the train wheel changes and the meshing load increases due to the output of the auxiliary pulse P2, the rotor often returns to the original low meshing load by rotating several steps. Therefore, as in this example, it is possible to survive the period in which the meshing load increases by outputting the second drive pulse P11 having a slightly larger effective power than the auxiliary pulse P2 by an appropriate step angle. After that, the hand movement can be performed as usual with the first drive pulse P1 having a small effective power that was previously supplied.

First or second drive pulse P1 or P
After 11 is output, in step ST3, the rotation detection pulse supply unit 24b supplies the detection pulse SP2, and the detection circuit 25 confirms whether or not the rotor 13 is normally rotated. If the rotor 13 is not rotating, the auxiliary pulse supply unit 2 is operated in step ST4.
The auxiliary pulse P2 is output by 4c, and subsequently, in step ST5, the degaussing pulse supply unit 24d outputs the degaussing pulse PE. Further, in step ST6, the effective power of the drive pulse is raised by one level. After that, in the control device 20 of the present example, the counter m for outputting the second drive pulse P11 is initialized in step ST15 so that the second drive pulse P11 is output in the next cycle.

On the other hand, in step ST3, the rotor 13
When the rotation is confirmed, the counter n of the first drive pulse P1 is incremented in step ST7. And
In step ST8, it is compared with the first set number of times N0 for reducing the effective power of the first drive pulse P1. When the counter n has reached the first set number N0, the effective power of the first drive pulse P1 is lowered by one step in step ST9, and the counter n is initialized in step ST10.

FIG. 3 shows an example in which a drive pulse or the like is supplied to the stepping motor 10 from the control device of this example using a timing chart. Similar to FIG. 9 described above, FIG. 3 illustrates p-channel MOSs 33a, n that excite a magnetic field (driving pole side) in the direction of the driving coil 11.
Gates GP1, GN1 and G of the channel MOS 32a and the p-channel MOS 34a for sampling
S1, a p-channel MOS 33b for exciting a magnetic field in the opposite direction opposite to the drive pole side, an n-channel MOS 32b, and a p-channel MO for sampling.
The control signals supplied to the gates GP2, GN2, and GS2 of S34b are used for the description, and the portions common to FIG. 8 are denoted by the same reference numerals and the description thereof will be omitted.

First, step S in the above flow chart.
When the time elapses at T1, the auxiliary pulse P2 is not output in the previous cycle, and the value of the counter m reaches the second set number M0. Therefore, at the time t41, the first drive of the voltage V10 is performed. The pulse P1 is output and the first cycle is started. Next, at time t42, step ST
In step 3, the rotation detection pulse SP2 is output, and if rotation is not detected, the auxiliary pulse P2 is output in step ST4 at time t43. When the auxiliary pulse P2 is output,
At time t44, the degaussing pulse PE is output in step ST5, and one cycle is completed.

When one second has passed from time t41, the next cycle is started. Since the auxiliary pulse P2 has been output in the previous cycle, the counter m has been cleared to zero.
Therefore, in this cycle, since the counter m has not reached the second set number M0 in step ST11, the level is raised from the first drive pulse P1 in step ST12 at time t51, that is, the effective power is larger. 2 drive pulses P11 are output. In the timing device 1 of this example, the voltage can be controlled by the step-up / down circuit 49, so the second drive pulse P11
As a result, a drive pulse having a voltage V11 higher than the voltage V10 is output at time t51. The voltage of the pulse supplied from the drive circuit 30 to the stepping motor 10 is determined by controlling the voltage output from the step-up / down circuit 49. However, for the sake of simplicity, the control voltage shown in the timing chart will be described below. The voltage of the drive pulse is shown by the voltage of the pulse.

At time t5 following the second drive pulse P11.
The pulse SP2 for rotation detection is supplied to 2 in step ST3, and the rotation of the rotor 13 is confirmed. Similarly, in the next cycle, the second drive pulse P11 is output at time t61, and the rotation detection pulse SP2 is output at time t62.
Is output. Furthermore, in the next cycle, time t
The second drive pulse P11 is output at 71 and the next time t
A pulse SP2 for rotation detection is output to 72. In the timing device 1 of this example, the second set number M0 is set to, for example, 3
And the counter m of the second drive pulse P11 becomes 3 in the next cycle starting from time t81. Therefore, in the next cycle starting from time t81, the voltage V10 ′ is increased by one rank from the cycle before the step ST11 to step ST2 and before the auxiliary pulse P2 (time t43) is supplied.
The first drive pulse P1 is output at time t81.

As described above, in the control device 20 employed in the timing device 1 of this example, after the load for driving the rotor 13 becomes high and the auxiliary pulse P2 is output, the conventional device is used. In that case, the effective power of the drive pulse (first drive pulse in this example) P1 is increased by one step to deal with the problem, whereas after the effective power of the first drive pulse P1 is increased by one rank. The second drive pulse P11 having an effective power that is one step or more higher than the effective power of the first drive pulse P1 is supplied to deal with the high load state. As described above, in most cases, the main cause of the increase in the load of the rotor 13 is that the meshing meshing load of the train wheel increases due to minute manufacturing variations and assembly variations. Further, the reason why the large load on the rotor 13 continues after that is that the meshing load may continue to increase due to the tolerance, and the meshing state of the wheel train due to the supply of the auxiliary pulse with a large driving torque. In most of the cases, there is a slight variation from when the drive pulse has a low torque. For this reason, it often occurs periodically, but since the rotor returns to the state in which it rotates with the original torque by continuously rotating for several steps, a large effective power pulse is required to increase the load. The number of step angles is small. Therefore,
As in this example, by supplying the drive pulse P11 whose effective power is slightly larger than the drive pulse P1 of the effective power that is normally supplied following the auxiliary pulse P2, it is possible to drive the step angle where the load is increased without a rotation error. it can.
Further, since it is not necessary to continuously supply an auxiliary pulse having a very large torque, it is possible to reduce power consumption and at the same time restore the state of the train wheel at an early stage. Then, after the step angle at which the meshing load increases,
It is possible to drive the rotor 13 by supplying the drive pulse P1 whose effective power is minimized. Therefore, unlike the conventional case, it is possible to avoid the situation in which the driving pulse of the effective power which is one or two steps or more of the actually required energy is constantly supplied, and is consumed by the stepping motor. It is possible to further reduce the power.

[Second Embodiment] FIG. 4 shows a schematic configuration of a clock device 1 according to a second embodiment of the present invention. The timing device 1 of the present example has substantially the same configuration as the timing device described with reference to FIG. 1, common parts are denoted by the same reference numerals, and detailed description thereof is omitted below. The control circuit 23 employed in the timing device 1 of this example includes a drive pulse supply section 24a for supplying the drive pulse P1 and the rotor 13
The rotation detection pulse supply unit 24b for supplying the rotation detection pulse SP2 and the auxiliary pulse supply unit 24c for supplying the auxiliary pulse P2.

The auxiliary pulse supply section 24c of the drive control circuit 24 of the present example is similar to the above-mentioned conventional circuit in the detection circuit 25.
When it is determined that the rotor 13 does not rotate, the auxiliary pulse P2 having large effective power is supplied.
In addition, the degaussing pulse P output following the auxiliary pulse P2
The degaussing pulse supply unit 24d of this example for controlling E outputs the degaussing pulse PE immediately before the next drive pulse P1 at a timing later than that of the conventional one, so that the next drive pulse P1 is substantially generated. The effective electric power is increased to give sufficient energy to rotate the rotor 13. Therefore, in the cycle following the auxiliary pulse P2 without increasing the energy of the drive pulse P1, the drive pulse with substantially large effective power can be supplied, and the step angle where the meshing load that causes the rotation failure increases can be overcome. be able to. In addition, the auxiliary pulse P2
Can be prevented from being continuously supplied, so that the meshing state of the train wheel can be quickly returned to the original state in which the meshing load is low. Therefore, in the control circuit 20 of the stepping motor 10 of this example, if the step angle where the load is increased due to the meshing tolerance or the axis deviation is overcome, the drive pulse whose effective power is reduced to the limit according to the state where the meshing load is small. The stepping motor 10 can be driven using P1. For this reason, the number of occasions where the drive pulse P1 of the effective power several steps above the limit value is supplied as in the conventional case is significantly reduced, and the power consumption when driving the stepping motor can be further reduced.

FIG. 5 is a flow chart showing the outline of the method of controlling the stepping motor employed in the timekeeping device 1 of this example. Also in this flowchart, the same steps as those in the control method described above are denoted by the same reference numerals, and detailed description of common portions will be omitted below. First, in step ST1, 1 for hand movement
Seconds are measured, and when 1 second has elapsed, drive pulse P1 is output in step ST2. Following this step ST
A pulse SP2 for rotation detection is output to 3 to detect whether or not the rotor 13 has rotated. When the rotation is not detected, the subroutine for supplying the auxiliary pulse P2 is executed. In this subroutine, in step ST4, the auxiliary pulse P2 having a large effective power is output, the degaussing pulse PE is then output, and the effective power of the drive pulse P1 is further increased by one rank as usual. In the present example, the degaussing pulse supply unit 24d delays the timing of outputting the degaussing pulse PE.
In step ST5, the degaussing pulse PE is output immediately before the start of the next cycle, that is, immediately before the output of the next drive pulse P1. When the degaussing pulse PE is output after the auxiliary pulse P2 is output, the process returns to the main routine and proceeds to step ST7. Thus, in the control method of this example,
After the output of the auxiliary pulse P2, the effective power of the drive pulse P1 is increased by one rank, and the power of the degaussing pulse PE is used to rotate and drive the auxiliary pulse P1 again.
2 is output and the effective power of the drive pulse P1 is continuously 2
It prevents situations such as an increase in rank or higher.

On the other hand, in step ST3, the rotor 13
If the rotation is detected, the subroutine for outputting the auxiliary pulse P2 is not executed, the counter n is incremented in step ST7, and the counter is compared with the first set number N0 in step ST8. If the counter n has reached the set number N0, the effective power of the drive pulse P1 is further reduced by one step in step ST9 to save power, and the counter n is initialized in step ST10.

FIG. 6 shows an example in which a drive pulse or the like is supplied to the stepping motor 10 from the control device of this example using a timing chart. Similar to FIG. 3 described above, FIG. 6 also shows the p-channel M that constitutes the drive circuit 30.
Each gate GP1 of the OS 33a, the n-channel MOS 32a and the sampling p-channel MOS 34a,
GN1 and GS1, and p-channel MOS33
The control signals supplied to the gates GP2, GN2 and GS2 of the b, n channel MOS 32b and the sampling p channel MOS 34b are shown,
The same parts as those described above are designated by the same reference numerals and the description thereof will be omitted.

When the first cycle is started at time t91, first, the drive pulse P1 of the voltage V10 is output from the drive pole side, and subsequently, at time t92, the rotation detection pulse SP2 is output. Then, when the rotor 13 does not rotate due to the meshing tolerance of the train wheel or the like, time t9
An auxiliary pulse P2 having a large effective electric power is output to the drive electrode 3 from the drive pole side. Next, in the control method of this example, the time t immediately before the time t101 at which the next cycle is started is reached.
A demagnetizing pulse PE is output from the reverse pole side at 94. Immediately after the degaussing pulse PE is output, the next cycle is started, and at time t101, the next drive pulse P1 is output on the drive pole side corresponding to the reverse pole side of the previous cycle. Therefore, the rotor 1 is driven by the demagnetization pulse PE and the drive pulse P1.
Thus, the rotor 13 can be rotated even at an angle at which the meshing load increases due to the output of the auxiliary pulse P2 in which the pulse that drives 3 is formed.

When the rotation detection pulse SP2 is output at time t102 and rotation is detected, in the next cycle, the drive pulse which is one rank higher than before the auxiliary pulse P2 is output at time t93 at time t111, that is, Voltage V
The drive pulse P1 of 10 'is output. As described above, in the control device and control method of the present embodiment, when the rotor 13 cannot rotate unless the auxiliary pulse P2 is used because the meshing load temporarily increases, the drive pulse P1 that follows It is possible to overcome the timing of high meshing load and continuously perform highly accurate hand movement without continuously increasing the effective power of the above.

As described above, the timing device 1 of the present embodiment outputs the second drive pulse P11 having a large effective power or the timing of outputting the degaussing pulse PE after the auxiliary pulse P2 is output. The drive pulse having substantially high effective power can be supplied by approaching the next drive pulse P1. Therefore, it is possible to cope with an increase in the load applied to the stepping motor 10 for a very short time due to the meshing tolerance or the like without increasing the effective power of the drive pulse P1 more than necessary. Therefore, when the meshing tolerance is returned to the original state and the load applied to the stepping motor 10 is also reduced, a small drive pulse P1 that is one rank higher than the effective power set previously is output. Therefore, in the past, the meshing tolerance,
After that, the effective power of the drive pulse P1 is increased by several steps due to the almost instantaneous increase of the load caused by the axis deviation caused by the output of the auxiliary pulse, and as a result, the drive power larger than the minimum required effective power is driven. While the stepping motor was driven by the pulse, the present invention can cope with the momentary increase in the load and can supply the drive pulse of the minimum necessary effective power when the load returns to the normal state. . Therefore, the power consumed by the stepping motor can be further reduced as compared with the conventional one, and a compact and long-life time measuring device can be realized, and even if the self-power generation type time measuring device is left for a long time, it can be continuously operated. It is possible to provide a timekeeping device that operates at any time. In addition, the present invention is not limited to a timepiece device such as a wristwatch device, and it is needless to say that the present invention can be provided to a device including a multifunctional timepiece such as a chronograph or other power generator and a stepping motor.

The waveforms of the drive pulse P1, the auxiliary pulse P2, the rotation detection pulse SP2 and the like described above are examples, and the waveforms can be set according to the characteristics of the stepping motor 10 employed in the timing device. Of course. Further, in the above example, the present invention has been described by taking a two-phase stepping motor suitable for the timekeeping device as an example, but it is needless to say that the present invention can be similarly applied to a stepping motor having three or more phases. . Further, instead of performing the control common to each phase, it is possible to supply the drive pulse with a pulse width and timing suitable for each phase. Further, it goes without saying that the driving method of the stepping motor is not limited to the one-phase excitation and may be the two-phase excitation or the 1-2-phase excitation.

[0045]

As described above, according to the control method and the control apparatus of the present invention, when the stepping motor is continuously moved by the drive pulse of the predetermined effective power, the effective power of the drive pulse is gradually reduced to be low. The stepping motor can be driven with power consumption. Further, according to the present invention, even if the load momentarily increases due to the tolerance of the meshing of the train wheel for transmitting the power of the stepping motor and the influence of the auxiliary pulse having a large torque for forcibly rotating thereafter, the load is continuously increased. Since the effective power itself of the drive pulse supplied to the device can be dealt with without increasing, the stepping motor can be driven by the drive pulse of the effective power reduced to almost the limit. Therefore, according to the present invention, it becomes possible to drive a stepping motor with lower power consumption than ever before, and a timekeeping device aiming for a small size and long life in the future, or a timekeeping device with a built-in power generator and no need for a battery. It is possible to provide a suitable control device and control method.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a timekeeping device accommodating a stepping motor and a power generator according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a control method of the control device shown in FIG.

FIG. 3 is a timing chart showing the movement of the control device shown in FIG.

FIG. 4 is a diagram showing a schematic configuration of a timekeeping device accommodating a stepping motor and a power generator according to a second embodiment of the present invention.

5 is a flowchart showing a control method of the control device shown in FIG.

FIG. 6 is a timing chart showing the operation of the control device shown in FIG.

FIG. 7 is a diagram showing a schematic configuration of a conventional timing device.

8 is a flowchart showing a control method of the control device shown in FIG.

9 is a timing chart showing the movement of the control device employed in the timing device shown in FIG.

[Explanation of symbols]

1, 9 ... Timer 10 ... Stepping motor 11 ... Drive coil 12 .. Driving stator ..Drive rotors 20..Control device 21 .. Crystal unit 22..Pulse synthesis circuit 23 .. Control circuit 24..Drive control circuit 24a ... First drive pulse supply unit 24b ··· Rotation detection pulse supply unit 24c ... Auxiliary pulse supply unit 24d ... Demagnetizing pulse supply unit 24e ... Level adjustment unit 24f ... Second drive pulse supply unit 25..Detection circuit 30 ... Drive circuit 41 ... Batteries 49 .. Buck-boost circuit 50 ... 51 ... 52 ... 53 ... Third wheel 54th car 55 ... 56 ... 61 ... second hand 62 ... 63 ... hour hand

Claims (9)

[Claims] 1. A controller for a stepping motor capable of rotationally driving a multi-pole magnetized rotor in a stator equipped with a drive coil, the first controller for driving the rotor with respect to the drive coil.
Drive means for supplying the drive pulse of No. 1, rotation detection means for detecting whether or not the rotor has rotated by the first drive pulse, and the first detection means when rotation of the rotor cannot be detected. Auxiliary means for supplying an auxiliary pulse having an effective power larger than that of the drive pulse, and level adjustment for stepwise reducing the effective power of the first drive pulse when the rotor continuously rotates a first set number of times. Means and a second drive pulse having an effective power that is one or several steps higher than the effective power of the first drive pulse adjusted by the level adjusting means a second set number of times after the auxiliary pulse is supplied. A stepping motor control device comprising: a second drive means for supplying. 2. The stepping motor control device according to claim 1, wherein the second drive means is capable of adjusting the effective power by changing the pulse width of the drive pulse. 3. The stepping motor control device according to claim 1, wherein the second drive means is capable of changing the voltage of the drive pulse to provide effective power. 4. A stepping motor control device capable of rotationally driving a multi-pole magnetized rotor in a stator having a drive coil, wherein a drive pulse for driving the rotor is supplied to the drive coil. Drive means, rotation detection means for detecting whether or not the rotor is rotated by the drive pulse, and effective power of the first drive pulse when the rotor is continuously rotated a first set number of times. Level adjusting means for gradually reducing, auxiliary means for supplying an auxiliary pulse having a larger effective power than the drive pulse when the rotation of the rotor cannot be detected, and the auxiliary pulse and the polarity after the auxiliary pulse. Degaussing pulse supply means for supplying different degaussing pulses immediately before the next driving pulse, and a stepping motor control device. 5. A method of controlling a stepping motor capable of rotationally driving a multi-pole magnetized rotor in a stator having a drive coil, the first step for driving the rotor with respect to the drive coil.
Drive step of supplying the drive pulse of No. 1, a rotation detection step of detecting whether or not the rotor is rotated by the first drive pulse, and the first detection step when rotation of the rotor cannot be detected. And an auxiliary step of supplying an auxiliary pulse having an effective power larger than that of the drive pulse, and a level adjustment for stepwise reducing the effective power of the first drive pulse when the rotor continuously rotates a first set number of times. And a second set number of times after the auxiliary pulse is supplied,
A second drive step of supplying a second drive pulse having an effective power which is one or several steps higher than the effective power of the first drive pulse adjusted in the level adjusting step. Control process. 6. The method of controlling a stepping motor according to claim 5, wherein the second driving step adjusts the effective power by changing the pulse width of the driving pulse. 7. The method for controlling a stepping motor according to claim 5, wherein in the second driving step, the effective power is adjusted by changing the voltage of the driving pulse. 8. A method of controlling a stepping motor capable of rotationally driving a multi-pole magnetized rotor in a stator having a drive coil, wherein a drive pulse for driving the rotor is supplied to the drive coil. A driving step, a rotation detecting step of detecting whether or not the rotor has rotated by the driving pulse, and an effective power of the first driving pulse when the rotor continuously rotates a first set number of times. A level adjustment step of gradually reducing, an auxiliary step of supplying an auxiliary pulse having a larger effective power than the drive pulse when rotation of the rotor cannot be detected, and the auxiliary pulse and the polarity after the auxiliary pulse. Degaussing pulse supplying step of supplying degaussing pulses different from each other immediately before the next driving pulse, and a stepping motor control method. 9. A stepping motor control device according to claim 1, a stepping motor for moving a clock hand by the drive pulse, and a pulse synthesizing means for outputting pulse signals of a plurality of frequencies. A time measuring device characterized by having.