JP2016187304A - Stepping motor control circuit, movement and analog electronic clock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve low power consumption.SOLUTION: A stepping motor 105 divides a detection section for detecting a rotating state of a rotor into a first segment, a second segment and a third segment while the rotor is being rotated by a main driving pulse; divides the second segment into a front segment and a rear segment; and changes a pulse-down frequency of the main driving pulse when a pattern of a determination value indicating whether or not an induction signal exceeding a predetermined reference threshold value has been detected in each segment thereof is a predetermined pattern.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a stepping motor control circuit that drives and controls a stepping motor, a movement including the stepping motor control circuit, and an analog electronic timepiece including the movement.

  Conventionally, in an analog electronic timepiece, when a plurality of types of main drive pulses P1 are prepared and the stepping motor is driven by any one of the main drive pulses, there is a margin in energy of the main drive pulse P1. A pulse control method has been developed to save power by performing pulse control so as to change (pulse down) to a main drive pulse P1 having a small energy.

For example, in the invention described in Patent Document 1, the detection section for detecting the rotation state is divided into a plurality of sections. When the pulse is down, the detection section is controlled by the detection value of the section T2. In consideration of the degree, pulse control is performed while aiming so that the induced signal VRs exceeding the reference threshold voltage Vcomp can be detected in the second half of the section T2 (section T2B) indicating that the drive margin has decreased. When the induced signal VRs exceeding the predetermined value is detected in the section T2B (the situation where the drive margin is small) continuously occurs for a predetermined first number of times, the pulse is downed, and the rotation situation with the small drive margin is the first state. Even when the rotation does not occur one time consecutively, if a rotation situation with a large drive margin occurs, the pulse is lowered before the first consecutive occurrence.
As a result, when the drive margin is large, the pulse down time is shortened to reduce the pulse, and when the operation is stable even if the drive margin is small, the pulse down time is increased. Thus, it is possible to reduce power consumption while stabilizing the operation.

However, since a pulse is generated only when a state with sufficient energy is continuously generated a predetermined number of times, there is a problem that energy is wasted before the pulse is downed.
Further, when the induced signal VRs exceeding the reference threshold voltage Vcomp is generated in the section T1, the induced signal VRs exceeding the reference threshold voltage Vcomp is generated in either the first half (section T2A) or the second half (section T2B) of the section T2. Even if it is, it is configured to maintain the rank. When the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T2A, the pulse margin is not reduced although the drive margin is sufficiently large and the pulse can be reduced. is there.

JP 2010-220461 A

The present invention has been made in view of the above problems, and it is an object of the present invention to further reduce power consumption by pulsing down as quickly as possible in a state where the drive margin is large.
Further, the present invention achieves lower power consumption by pulsing down as quickly as possible in a state where the drive margin is large, and at the same time, by pulsing down to a drive pulse of small energy that can be rotated as much as possible. The challenge is to reduce power consumption.

  According to the first aspect of the present invention, the rotation detection unit that detects the rotation state of the stepping motor in a predetermined detection section, a plurality of main drive pulses having different energy from each other, and energy higher than the main drive pulses. When driving is performed by selecting a drive pulse corresponding to the rotation status from among the correction drive pulses and the rotation status indicates that the energy of the driven main drive pulse has a margin, the energy is higher than that of the main drive pulse. And a control unit that drives the main drive pulse with a smaller main drive pulse, and the detection section T is defined as a first section immediately after driving by the main drive pulse, a second section after the first section, and the second section. In a state where the drive section is small so that the rank of the main drive pulse is not changed while the second section is divided into a front section and a rear section while being divided into a third section after the section. The first section is a section for determining the first forward rotation state of the rotor in the second quadrant of the space centered on the rotor of the stepping motor, and the second section is the second quadrant and the third quadrant of the rotor. A section for determining the first forward rotation state, the third section is a section for determining a rotation state after the first reverse rotation of the rotor in the third quadrant, and the rotation detector is configured to detect the stepping in the detection section. A detection value pattern indicating whether an induction signal generated by the rotation of the motor is detected and an induction signal exceeding a predetermined reference threshold voltage is detected in each interval (the determination value in the first interval, the second interval front side) A detection signal indicating a rotation state based on a determination value of the section, a determination value of the second section after the second section, and a determination value of the third section), and the control unit outputs the detection signal indicating the predetermined pattern Stepping motor control circuit, characterized in that the pulse down each time driving the main drive pulse is provided when the.

  According to a second aspect of the present invention, there is provided a movement comprising the stepping motor control circuit.

  According to a third aspect of the present invention, there is provided an analog electronic timepiece comprising the movement.

According to the stepping motor control circuit of the present invention, it is possible to further reduce the power consumption by pulsing down as quickly as possible when the drive margin is large. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. It becomes possible to plan.
According to the movement of the present invention, it is possible to construct an analog electronic timepiece capable of further reducing power consumption by pulsing down as quickly as possible in a state where the drive margin is large. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. An analog electronic timepiece that can be designed can be constructed.
Further, according to the analog electronic timepiece according to the invention, it is possible to further reduce the power consumption by pulsing down as quickly as possible when the drive margin is large. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. It becomes possible to plan.

It is a block diagram of a stepping motor control circuit, a movement, and an analog electronic timepiece according to an embodiment of the present invention. It is a block diagram of the stepping motor used for embodiment of this invention. It is a timing diagram for demonstrating operation | movement of embodiment of this invention. It is a determination chart explaining operation | movement of embodiment of this invention. It is a flowchart which shows operation | movement of embodiment of this invention.

FIG. 1 is a block diagram showing a stepping motor control circuit according to an embodiment of the present invention, a movement including the stepping motor control circuit, and an analog electronic timepiece including the movement, and shows an example of an analog electronic wristwatch. .
In FIG. 1, an analog electronic timepiece includes an oscillation circuit 101 that generates a signal of a predetermined frequency, a frequency dividing circuit 102 that divides the signal generated by the oscillation circuit 101 and generates a clock signal that serves as a time reference, and an analog electronic timepiece. Control circuit 103 that performs control of each electronic circuit element constituting the control, change control of drive pulse, and the like, and a drive pulse selection circuit that selects and outputs a drive pulse for motor rotation driving based on a control signal from the control circuit 103 104, a stepping motor 105 that is rotationally driven by the drive pulse from the drive pulse selection circuit 104, and a time hand that is rotationally driven by the stepping motor 105 to display the time (in the example of FIG. 1, the hour hand 107, the minute hand 108, and the second hand 109 The analog display unit 106 having three types) is provided.

The analog electronic timepiece includes a watch case 112, an analog display unit 106 is provided on the outer surface side of the watch case 112, and a movement 113 is provided inside the watch case 112.
Further, in the analog electronic timepiece, the rotation detection circuit 110 for detecting the induced signal VRs generated by free vibration of the stepping motor 105 and representing the rotation state in a predetermined detection section, the rotation detection circuit 110 exceeds a predetermined reference threshold voltage Vcomp. It has a detection section discriminating circuit 111 that compares the detected time of the induced signal VRs with the detected section to determine in which section the induced signal VRs is detected. As will be described later, the detection section for detecting whether or not the stepping motor 105 has rotated is divided into four sections.

  The rotation detection circuit 110 is configured to detect the induced signal VRs using the same principle as that of the rotation detection circuit described in Patent Document 1, and rotates when the stepping motor 105 rotates. When the motor speed exceeds a certain speed, an induced signal VRs exceeding a predetermined reference threshold voltage Vcomp is generated, and when the motor 105 does not rotate, the induced signal VRs is The reference threshold voltage Vcomp is set so as not to exceed the reference threshold voltage Vcomp.

The oscillation circuit 101, the frequency dividing circuit 102, the control circuit 103, the drive pulse selection circuit 104, the stepping motor 105, the rotation detection circuit 110, and the detection section determination circuit 111 are components of the movement 113.
In general, a timepiece mechanical body composed of devices such as a timepiece power source and a time reference is called a movement. Electronic devices are sometimes called modules. When the watch is completed, a dial and hands are attached to the movement and housed in a watch case.

  Here, the oscillation circuit 101 and the frequency dividing circuit 102 constitute a signal generation unit, and the analog display unit 106 constitutes a time display unit. The rotation detection circuit 110 and the detection section determination circuit 111 constitute a rotation detection unit. The control circuit 103 and the drive pulse selection circuit 104 constitute a control unit. Further, the oscillation circuit 101, the frequency dividing circuit 102, the control circuit 103, the drive pulse selection circuit 104, the rotation detection circuit 110, and the detection section determination circuit 111 constitute a stepping motor control circuit.

FIG. 2 is a configuration diagram of the stepping motor 105 used in the embodiment of the present invention, and shows an example of a timepiece stepping motor generally used in an analog electronic timepiece.
In FIG. 2, the stepping motor 105 includes a stator 201 having a rotor housing through hole 203, a rotor 202 rotatably disposed in the rotor housing through hole 203, a magnetic core 208 joined to the stator 201, and a winding around the magnetic core 208. A rotated coil 209 is provided. When the stepping motor 105 is used in an analog electronic timepiece, the stator 201 and the magnetic core 208 are fixed to a base plate (not shown) with screws (not shown) and joined to each other. The coil 209 has a first terminal OUT1 and a second terminal OUT2.

  The rotor 202 is magnetized to two poles (S pole and N pole). A plurality of (two in this embodiment) notch portions (outer notches) 206 and 207 are provided at positions facing each other across the rotor accommodating through hole 203 at the outer end portion of the stator 201 formed of a magnetic material. Is provided. Saturable portions 210 and 211 are provided between the outer notches 206 and 207 and the rotor accommodating through hole 203.

  The saturable portions 210 and 211 are configured not to be magnetically saturated by the magnetic flux of the rotor 202 but to be magnetically saturated when the coil 209 is excited to increase the magnetic resistance. The through hole 203 for accommodating the rotor has a circular hole shape in which a plurality of (two in the present embodiment) half-moon-shaped notches (inner notches) 204 and 205 are integrally formed at the opposing portion of the through hole having a circular outline. It is configured.

  The notches 204 and 205 constitute a positioning part for determining the stop position of the rotor 202. In a state where the coil 209 is not excited, the rotor 202 has a position corresponding to the positioning portion as shown in FIG. 2, in other words, a line segment connecting the notches 204 and 205 with the magnetic pole axis A of the rotor 202. Is stably stopped at a position (angle θ0 position) perpendicular to the angle. An XY coordinate space centered on the rotation axis (rotation center) of the rotor 202 is divided into four quadrants (first quadrant I to fourth quadrant IV).

  Now, a rectangular-wave drive pulse is supplied from the drive pulse selection circuit 104 between the terminals OUT1 and OUT2 of the coil 209 (for example, the first terminal OUT1 side is positive and the second terminal OUT2 side is negative), and the arrow in FIG. When a current i flows in the direction, a magnetic flux is generated in the stator 201 in the direction of the broken arrow. As a result, the saturable portions 210 and 211 are saturated and the magnetic resistance is increased, and then the rotor 202 rotates 180 degrees in the direction of the arrow in FIG. 2 due to the interaction between the magnetic pole generated in the stator 201 and the magnetic pole of the rotor 202. Then, the magnetic pole axis stably stops at the angle θ1 position. Incidentally, the rotation direction (counterclockwise direction in FIG. 2) for causing the normal operation (in this embodiment, since it is an analog electronic timepiece to move the hand) by rotating the stepping motor 105 is defined as the positive direction. The reverse (clockwise direction) is the reverse direction.

  Next, from the drive pulse selection circuit 104, a drive pulse having a reverse polarity rectangular wave is supplied to the terminals OUT1 and OUT2 of the coil 209 (the first terminal OUT1 side is connected to the negative electrode so that the drive polarity is opposite to that of the drive). When the second terminal OUT2 side is the positive electrode) and a current is passed in the direction indicated by the arrow in FIG. Thereby, the saturable portions 210 and 211 are first saturated, and then the rotor 202 rotates 180 degrees in the same direction (positive direction) as described above due to the interaction between the magnetic pole generated in the stator 201 and the magnetic pole of the rotor 202. The magnetic pole axis stops stably at the angle θ0 position.

Thereafter, by supplying signals with different polarities (alternating signals) to the coil 209 in this way, the above operation is repeated, and the rotor 202 can be continuously rotated 180 degrees in the direction of the arrow. It is configured as follows. In the present embodiment, a plurality of main drive pulses P10 to P1n having different energy and a correction drive pulse P2 having larger energy than each of the main drive pulses P1 are used as drive pulses.
The control circuit 103 basically drives the stepping motor 105 to rotate by alternately driving the main drive pulses P1 having different polarities. When the control circuit 103 cannot rotate by the main drive pulse P1, the main drive pulse P1 is driven. It is rotationally driven by a correction drive pulse P2 having the same polarity as the pulse P1.

FIG. 3 is a timing chart when the stepping motor 105 is driven by the main drive pulse P1 in the embodiment of the present invention. The rotation state represents the margin of drive pulse energy relative to the load, the rotational behavior of the rotor 202, and the induction. The generation timing of the signal VRs, the pattern (T1 to T3) of the induced signal VRs representing the rotation state, and the pulse control operation are shown.
In FIG. 3, P1 represents the drive range of the main drive pulse P1, and the range in which the rotor 202 is rotationally driven by the main drive pulse P1, and a to e are due to free vibration after the drive of the main drive pulse P1 is stopped. This is an area representing the rotational position of the rotor 202.

A predetermined time immediately after driving by the main drive pulse P1 is a section T1 (first section), a predetermined time after the section T1 is a section T2 (second section), and a predetermined time after the section T2 is a section T3 (third Section). Further, the section T2 is divided into a front section T2_Frt and a rear section T2_End.
When detecting the induced signal VRs in the detection section T, the rotation detection circuit 110 is configured to detect the induced signal VRs by sampling the induced signal VRs at a predetermined sampling period. The detection section T includes a plurality of sampling periods, and the induced signal VRs is detected at a plurality of time points by sampling the induced signal VRs in each sampling period.

  In the example of FIG. 3, the last sampling period in the section T2 is set as the rear section T2_End. In the rear section T2_End, the rotation detection circuit 110 samples and detects the induced signal VRs only once. The other sections T1, T2_Frt, and T3 are configured by a plurality of sampling periods, and the induced signal VRs is detected at a plurality of time points. The time interval of the front section T2_Frt is configured to be the maximum, and the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the front section T2_Frt as much as possible so as to pulse down to the drive limit. . Note that the rear section T2_End can be configured to have a time width of ½ or less of the section T2, and even in this configuration, it is possible to appropriately detect the rotation state, Power consumption can be reduced.

  In this way, the entire detection section T starting immediately after driving by the main drive pulse P1 is divided into a plurality of sections (in this embodiment, four sections (section T1, section T2 front section T2_Frt, section T2 rear section T2_End, section T3). In this embodiment, there is no section (mask section) in which the induced signal VRs immediately after driving by the main driving pulse P1 is not used for determining the rotation state.

  When the XY coordinate space where the main magnetic pole A of the rotor 202 is located by rotation of the rotor 202 is divided into the first quadrant I to the fourth quadrant IV, the energy of the main drive pulse P1 when driving a normal load is divided. Depending on the size of the margin (energy margin), the section T1, the section T2 front side section T2_Frt, the section T2 rear section T2_End, and the section T3 can be expressed as follows. Here, the normal load means a load that is driven at a normal time, and in the present embodiment, a load when driving the time hand (hour hand 107, minute hand 108, second hand 109) is a normal load.

  That is, it has a minimum energy that can rotate the stepping motor 105 even when the energy margin is in the driving margin (when the main driving pulse P1 is changed to the main driving pulse P1 having a small energy (pulse down)). Section T1 is a section for determining the first forward rotation state of the rotor 202 in the second quadrant II and the third quadrant III of the space around the rotor 202, and the section T2 front side T2_Frt is the third quadrant III. , The section for determining the first forward rotation situation and the first reverse rotation situation of the rotor 202, the rear side T2_End of the section T2 is the section for determining the first reverse rotation situation of the rotor 202 in the third quadrant III, and the section T3 is In the third quadrant III, it is a section for determining the rotation state after the first reverse rotation of the rotor 202.

  In a rotation state with a large drive margin in which the energy margin is increased by a predetermined amount from the rotation state during the drive margin, the section T1 is the first of the rotor 202 in the second quadrant II and the third quadrant III of the space centered on the rotor 202. In the third quadrant III, the section for determining the forward rotation situation, the first section T2_Frt in the third direction is the section for determining the first forward rotation situation and the first reverse rotation situation of the rotor 202, and the second section T2_End in the second section T2 is the third section. In the quadrant III, the section for determining the first reverse rotation state of the rotor 202, and the section T3 is the section for determining the rotation state after the first reverse rotation of the rotor 202 in the third quadrant III.

  In the rotational state where the drive margin is maximized by increasing the energy margin by a predetermined amount from the rotational state where the drive margin is large, the section T1 indicates the first forward rotation state of the rotor 202 in the third quadrant III of the space centered on the rotor 202. The section to be determined, the section T2 front section T2_Frt is a section to determine the first reverse rotation state of the rotor 202 in the third quadrant III, and the section T2 rear section T2_End is the first reverse rotation state of the rotor 202 in the third quadrant III. In the third quadrant III, the section T3 is a section for determining a rotation state after the first reverse rotation of the rotor 202 in the third quadrant III.

  Further, in a rotational state with a small drive margin that is reduced by a predetermined amount from the rotational state during the drive margin, the section T1 is a section for determining the forward rotation state of the rotor 202 in the second quadrant II, and the section T2 front section T2_Frt is a section for determining the first positive rotation state of the rotor 202 in the second quadrant II and the third quadrant III, and a rear section T2_End of the section T2 is a first positive rotation state of the rotor 202 in the third quadrant III. A section T3 is a section for determining a rotation state after the first reverse rotation of the rotor 202 in the third quadrant III. The control circuit 103 does not change the rank of the main drive pulse P1 when the drive margin is small.

  Further, in a rotational state in which the energy margin is reduced by a predetermined amount from the rotational state in which the driving margin is small, the section T1 is a section for determining the forward rotation state of the rotor 202 in the second quadrant II. T2_Frt is a section for determining the first forward rotation state of the rotor 202 in the second quadrant II and the third quadrant III, and the rear section T2_End of the section T2 is the rotation state of the first forward rotation of the rotor 202 in the third quadrant III. In the third quadrant III, the section T3 is a section for determining a rotation state after the first reverse rotation of the rotor 202 in the third quadrant III.

  Vcomp is a reference threshold voltage for determining the voltage level of the induced signal VRs generated by the stepping motor 105. When the rotor 202 performs a fast operation exceeding a predetermined speed, such as when the stepping motor 105 rotates, etc. When the induced signal VRs exceeds the reference threshold voltage Vcomp and the rotor 202 does not perform a fast operation exceeding a predetermined speed as in the case where the induced signal VRs does not rotate, the induced signal VRs is determined so as not to exceed the reference threshold voltage Vcomp. The threshold voltage Vcomp is set.

  For example, in FIG. 3, in the stepping motor control circuit according to the present embodiment, the induced signal VRs generated in the region b is detected in the section T1 and the front section T2_Frt in the section T1 and generated in the area c in the state where the driving margin is in effect. The induced signal VRs is detected in the section T2 front section T2_Frt, the section T2 rear section T2_End, and the section T3, and the induced signal VRs generated after the region c is detected in the section T3.

  When the rotation detection circuit 110 detects the induced signal VRs exceeding the reference threshold voltage Vcomp, the determination value is “1”, and when the rotation detection circuit 110 cannot detect the induced signal VRs exceeding the reference threshold voltage Vcomp, the determination value When “0” is set, in the example in FIG. 3 in the driving margin, a pattern indicating the rotation state (the determination value of the first section T1, the determination value of the second section T2 front section T # Frt, the second section rear section T2_End). (1, 1, 1/0, 1/0) is obtained as the determination value (the determination value of the third section T3). The control circuit 103 determines that the rotation is within the drive margin with sufficient drive energy for the load, and when this state continues for a predetermined second number of times (80 times in the present embodiment), the main drive pulse P1 is driven. Pulse control is performed to pulse down the energy.

  In the state where the drive margin is maximum, the induced signal VRs generated in the region b is detected in the section T1, and the induced signal VRs generated in the region c is detected in the section T2 front section T2_Frt and the section T2 rear section T2_End. The induced signal VRs generated in the area after the area c is detected in the section T3. In the example of FIG. 3, the pattern (0, 1, 1/0, 1/0) is obtained, and the control circuit 103 determines that the rotation has the maximum driving margin, and pulse-downs the driving energy of the main driving pulse P1. The pulse control is performed as follows. As a result, if it is determined that the rotation has the maximum drive margin every time the main drive pulse P1 is driven, the pulse control is performed so that the drive energy of the main drive pulse P1 is reduced every time the main drive pulse P1 is driven. Will do.

  In the state where the driving margin is small, the induced signal VRs generated in the region a is detected in the section T1 and the section T2 front section T2_Frt, and the induced signal VRs generated in the area b is the section T2 front section T2_Frt and the section T2 rear side. The induced signal VRs detected in the section T2_End and generated after the area c is detected in the section T3. In the example of FIG. 3, the pattern (1, 0, 1, 1/0) is obtained, and the control circuit 103 determines that the rotation has a small drive margin and maintains the main drive pulse P1 without changing it. The pulse control is performed as follows.

  In the state where the drive margin is minimum, the induced signal VRs generated in the region a is detected in the section T1 and the section T2 front side section T2_Frt, and the induced signal VRs generated in the area b is the section T2 front side section T2_Frt and the section T2 rear side. The induced signal VRs detected in the section T2_End and generated after the area c is detected in the section T3. In the example of FIG. 3, the pattern (1/0, 0, 0, 1) is obtained, and the control circuit 103 determines that the rotation has the minimum drive margin, so that the main drive pulse P1 has the main energy of one rank. Pulse control is performed so as to change to a drive pulse (pulse up).

  FIG. 4 is a determination chart summarizing the operation of the embodiment of the present invention. In FIG. 4, as described above, the determination value “1” is obtained when the induced signal VRs exceeding the reference threshold voltage Vcomp is detected, and the determination value “0” is detected when the induced signal VRs exceeding the reference threshold voltage Vcomp cannot be detected. ". “1/0” represents that the determination value may be “1” or “0”.

  As shown in FIG. 4, the rotation detection circuit 110 detects the presence or absence of the induced signal VRs exceeding the reference threshold voltage Vcomp, and the control is performed based on the pattern in which the detection interval determination circuit 111 determines the detection timing of the induced signal VRs. Referring to the determination chart of FIG. 4 stored in the circuit 103, the control circuit 103 and the drive pulse selection circuit 104 perform pulse control, which will be described later, such as pulse-up and pulse-down of the main drive pulse P1 or drive by the correction drive pulse P2. Then, the rotation of the stepping motor 105 is controlled.

For example, in the case of the pattern (1/0, 0, 0, 0), the control circuit 103 determines that the stepping motor 105 is not rotating (non-rotating) and drives the stepping motor 105 with the correction driving pulse P2. After the drive pulse selection circuit 104 is controlled as described above, the drive pulse selection circuit 104 is controlled so as to drive up to the main drive pulse P1 that is one rank higher in the next drive.
In the case of the pattern (0, 0, 1, 1/0), the control circuit 103 determines that the rotation has a large driving margin, and this state continues for a predetermined first number of times (in this embodiment, 20 times). In this case, pulse control is performed so that the drive energy of the main drive pulse P1 is pulsed down.

FIG. 5 is a flowchart showing the operation of the embodiment of the present invention, and is a flowchart mainly showing the processing of the control circuit 103.
The operation of the embodiment of the present invention will be described in detail below with reference to FIGS.

In FIG. 1, an oscillation circuit 101 generates a reference clock signal having a predetermined frequency, and a frequency dividing circuit 102 divides the signal generated by the oscillation circuit 101 to generate a clock signal serving as a time reference, and a control circuit 103. Output to.
The control circuit 103 counts the time signal and performs a time measuring operation. First, the energy rank n and the frequency N of the main drive pulse P1n are set to 0 (step S501 in FIG. 5), and the main drive pulse P10 having the minimum pulse width is used. A control signal is output so as to drive the stepping motor 105 to rotate (steps S502 and S503).

  The drive pulse selection circuit 104 selects the main drive pulse P10 corresponding to the control signal from the control circuit 103 and rotationally drives the stepping motor 105. The stepping motor 105 is rotationally driven by the main drive pulse P10 to rotationally drive the time hands 107 to 109. Thus, when the stepping motor 105 rotates normally, the current time is displayed on the display unit 106 by the time hands 107-109.

  The control circuit 103 determines whether or not the rotation detection circuit 110 has detected the induced signal VRs of the stepping motor 105 that exceeds a predetermined reference threshold voltage Vcomp, and the detection interval determination circuit 111 detects the induction signal VRs. It is determined whether or not t is determined to be within the section T1 (that is, whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected within the section T1) (step S504).

  When the control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the section T1 in the processing step S504 (the pattern is (0, x, x, x)). However, the determination value “x” does not matter whether the determination value is “1” or “0”.) Whether the induced signal VRs exceeding the reference threshold voltage Vcomp is detected within the interval T2_Frt on the front side of the interval T2 It is determined whether or not (step S505).

The control circuit 103 determines in the processing step S505 that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the section T2 front section T2_Frt (in the case where the pattern is (0, 0, x, x)). It is determined whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the rear section T2_End of the section T2 (step S506).
The control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the rear section T2_End of the section T2 in the processing step S506 (when the pattern is (0, 0, 0, x)). It is determined whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T3 (step S507).

  The control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the section T3 in the processing step S507 (the case where the pattern is (0, 0, 0, 0), After the stepping motor 105 is forcibly rotated by the correction driving pulse P2 having the same polarity as the main driving pulse P1 in the processing step S503 (step S508), the rank n of the main driving pulse P1 is If it is not the maximum rank m, the main drive pulse P1 is pulsed up and changed to the main drive pulse P1 (n + 1), and then the process returns to step S502, and the next drive is driven by this main drive pulse P1 (n + 1) (step S509, S510).

  In the processing step S509, when the rank n of the main drive pulse P1 is the maximum rank m, the control circuit 103 changes the main drive pulse P1 to the main drive pulse P1 (na) having a small amount of energy. Returning to processing step S502, the next drive is driven by this main drive pulse P1 (na) (step S511). In this case, since the drive pulse P1max with the maximum energy rank m in the main drive pulse P1 is in a non-rotatable state, energy waste when driving with the main drive pulse P1max with the maximum energy rank m is reduced at the next drive. Can do. At this time, in order to obtain a large power saving effect, the main drive pulse P10 having the minimum energy may be changed.

  When the control circuit 103 determines in process step S507 that the induced signal VRs exceeding the reference threshold voltage Vcomp has been detected in the section T3 (in the case where the pattern is (0, 0, 0, 1)). If the rank n of the main drive pulse P1 is not the maximum rank m, the main drive pulse P1 is pulsed up, changed to the main drive pulse P1 (n + 1), and the process returns to the processing step S502, and the next drive is the main drive. Driven by the pulse P1 (steps S609 and S610).

Since the rank cannot be changed when the rank n of the main drive pulse P1 is the maximum rank m in the process step S609, the control circuit 103 returns to the process step S502 without changing the main drive pulse P1, and the next drive is performed. Driving is performed by the main drive pulse P1 (step S608).
The control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp has been detected in the rear section T2_End of the section T2 in the processing step S506 (the case where the pattern is (0, 0, 1, x)). .), It is determined whether or not the rank n of the main drive pulse P1 is the lowest rank 0 (step S515).

  If the control circuit 103 determines in step S515 that the rank n of the main drive pulse P1 is not the lowest rank 0, the control circuit 103 adds 1 to the number N of consecutive occurrences (step S516), and the number N is a predetermined first number (this In the embodiment, it is determined whether or not (20 times) (step S517). If the predetermined number of times has not been reached, the rank of the main drive pulse P1 is not changed and the process returns to step S502 (step S514). When the predetermined number of times has been reached, the rank of the main drive pulse P1 is pulsed down and the number of consecutive occurrences N is reset to 0, and the process returns to step S502 (step S518).

If the rank n of the main drive pulse P1 is determined to be the lowest rank 0 in process step S515, the control circuit 103 returns to process step S502 without changing the rank of the main drive pulse P1 (step S514).
The control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp has been detected in the section T2 front section T2_Frt in the processing step S505 (the pattern is (0, 1, x, x)). ), It is determined whether or not the rank n of the main drive pulse P1 is the lowest rank 0 (step S512).

  If the control circuit 103 determines in process step S515 that the rank n of the main drive pulse P1 is not the lowest rank 0, the control circuit 103 pulses down the rank of the main drive pulse P1 and returns to process step S502 (step S513). When it is determined that the rank n of the drive pulse P1 is the lowest rank 0, the process returns to the processing step S502 without changing the rank of the main drive pulse P1 (step S514).

On the other hand, when the control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T1 in the processing step S504 (the case is that the pattern is (1, x, x, x)). .), It is determined whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T2 front side section T2_Frt (step S601).
The control circuit 103 determines in the processing step S601 that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the section T2 front section T2_Frt (when the pattern is (1, 0, x, x)). It is determined whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the rear section T2_End of the section T2 (step S602).

When the control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the rear section T2_End of the section T2 in the processing step S602 (when the pattern is (1, 0, 0, x)) It is determined whether or not the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T3 (step S603).
In the processing step S603, the control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is not detected in the section T3 (the case where the pattern is (1, 0, 0, 0), In the case of non-rotation), the process proceeds to processing step S508, and when it is determined that the induced signal VRs exceeding the reference threshold voltage Vcomp is detected within the section T3 (the pattern is (1, 0, 0, 1)). In this case, the process proceeds to processing step S609.

When the control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the section T2 rear section T2_End in the processing step S602 (the pattern is (1, 0, 1, x)). ), The rank of the main drive pulse P1 is maintained without change, and the process returns to step S502 (step S608).
The control circuit 103 determines that the induced signal VRs exceeding the reference threshold voltage Vcomp is detected in the processing section S601 within the section T2 front section T2_Frt (the pattern is (1, 1, x, x)). ), It is determined whether or not the rank n of the main drive pulse P1 is the lowest rank 0 (step S604).

When determining that the rank n of the main drive pulse P1 is not the lowest rank 0 in the processing step S604, the control circuit 103 adds 1 to the number N of consecutive occurrences (step S605), and the number N is a predetermined second number (this In the embodiment, it is determined whether or not it has reached 80 times (step S606). If the predetermined number has not been reached, the rank of the main drive pulse P1 is not changed and the process returns to step S502 (step S608). When the predetermined number of times is reached, the rank of the main drive pulse P1 is pulsed down and the number of consecutive occurrences N is reset to 0, and the process returns to step S502 (step S607).
When the rank n of the main drive pulse P1 is determined to be the lowest rank 0 in the processing step S604, the control circuit 103 proceeds to the processing step S608.

  As described above, the stepping motor control circuit according to the embodiment of the present invention includes the rotation detection unit that detects the rotation state of the stepping motor 105 in the predetermined detection section T and the plurality of main drive pulses having different energy from each other. The drive pulse corresponding to the rotation state is selected and driven from P1 and the correction drive pulse P2 having a larger energy than the main drive pulse P1, and the energy of the driven main drive pulse P1 has a margin. A control unit that drives the main drive pulse P1 with energy lower than that of the main drive pulse P1 when the rotation state indicates, and the detection section T is set to a second state immediately after the drive by the main drive pulse P1. The first section T1, the second section T2 after the first section T1, the third section T3 after the second section T2, and the second section 2 is divided into a front section T # Frt and a rear section T # End, and the first section T1 is a space centered on the rotor 202 of the stepping motor 105 in a state where the drive margin is small without changing the rank of the main drive pulse P1. In the second quadrant II, the section for determining the first forward rotation situation of the rotor 202, the second section T2 is the section for determining the first forward rotation situation of the rotor 202 in the second quadrant II and the third quadrant III, The third section T3 is a section for determining the rotation state after the first reverse rotation of the rotor 202 in the third quadrant III, and the rotation detection unit generates an induced signal VRs generated by the rotation of the stepping motor 105 in the detection section T. A pattern of determination values indicating whether or not an induced signal VRs that is detected and exceeds a predetermined reference threshold voltage Vcomp is detected in each section T1 to T3. Detection signal indicating the rotation status by the determination value of the first section T1, the determination value of the second section front section T # Frt, the determination value of the second section rear section T # End, the determination value of the third section T3 The control unit is characterized in that when the pattern is a predetermined pattern, the main drive pulse P1 is pulsed down every time it is driven.

Here, the predetermined pattern can be configured to be (0, 1, 1/0, 1/0).
The controller may be configured to pulse down when the pattern (0, 0, 1, 1/0) is obtained for a predetermined first number of times.
In addition, when the pattern indicates that an induced signal exceeding the reference threshold voltage is generated in the first section, the control unit is configured to perform the reference in the second section front section and the second section rear section. It can be configured to determine whether or not to pulse down the main drive pulse based on a pattern of induced signals exceeding a threshold voltage.

Further, the detection section T is configured by a plurality of sampling periods in which the rotation detection unit detects the induced signal VRs, and the second section rear section T2_End is the last sampling period in the second section T2. can do.
The control unit maintains the rank of the main drive pulse in the case of the pattern (1, 0, 1, 1/0), and the pattern (1, 1, 1/0, 1/0) is a predetermined second. When it is obtained continuously, it can be configured to pulse down.
Further, the second number of times can be configured to be greater than the first number of times.

  Therefore, in a state where the drive margin is large, it is possible to further reduce power consumption by pulsing down as quickly as possible. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. It becomes possible to plan.

In addition, prepare multiple types of periods until pulse down according to the size of the drive margin (so that the frequency of pulse down can be changed), and the state with a large drive margin than the state with a small drive margin Further, by performing pulse down in a shorter period, it is possible to realize further lower power consumption.
In addition, since the main drive pulse P1 is pulse controlled to pulse down to the drive limit, the load fluctuation can be achieved by controlling the pulse so that the rank of the drive pulse is increased for a large load while realizing low power consumption. It is possible to cope with the minimum power change.

  In addition, according to the movement 113 according to the embodiment of the present invention, it is possible to construct an analog electronic timepiece capable of further reducing power consumption by pulsing down as quickly as possible in a state where the drive margin is large. it can. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. An analog electronic timepiece that can be designed can be constructed.

  Further, according to the analog electronic timepiece according to the embodiment of the present invention, it is possible to further reduce power consumption by pulsing down as quickly as possible in a state where the drive margin is large. In addition, in a state where the drive margin is large, the pulse is reduced as quickly as possible to reduce the power consumption, and the pulse is reduced to a drive pulse with as little energy as possible to reduce the power consumption. Therefore, when a battery is used as a power source, it can be used for a long time.

In the above-described embodiment, the pulse width is changed in order to change the energy of each drive pulse. However, the drive energy is also changed by changing the number of comb-like pulses or changing the pulse voltage. It is possible.
Moreover, although the example of the electronic timepiece has been described as an application example of the stepping motor, it can be applied to an electronic device using the motor.

The stepping motor control circuit according to the present invention is applicable to various electronic devices that use the stepping motor.
The movement and the electronic timepiece according to the present invention can be applied to various analog electronic timepieces including an analog electronic wristwatch with a calendar function and a chronograph timepiece.

DESCRIPTION OF SYMBOLS 101 ... Oscillator 102 ... Frequency divider 103 ... Control circuit 104 ... Drive pulse selection circuit 105 ... Stepping motor 106 ... Analog display 107 ... Hour hand 108 ... Minute hand 109 ... second hand 110 ... rotation detection circuit 111 ... detection section discrimination circuit 112 ... watch case 113 ... movement 201 ... stator 202 ... rotor 203 ... through hole for accommodating the rotor 204, 205 ... Notch (inner notch)
206, 207 ... Notch (outer notch)
208 ... Magnetic core 209 ... Coils 210, 211 ... Saturable portion OUT1 ... First terminal OUT2 ... Second terminal

Claims (6)

A rotor rotated by the energy of the main drive pulse;
A first section set after application of the main drive pulse, a second section set after the first section, and a detection section including a third section set after the second section, Detecting an induced signal generated by applying the main drive pulse in a detection section in which a second section is set to be divided into a front section of the second section and a rear section of the second section following the front section of the second section A rotation detecting unit for detecting a rotation state of the rotor by
The energy of the main drive pulse is determined according to a pattern indicating a combination in which the induced signal exceeding a reference threshold voltage is detected in the first section, the second section front section, and the second section rear section. A control unit for changing the frequency of setting a low value,
A stepping motor control circuit comprising:   The controller does not detect an induced signal exceeding the reference threshold voltage in the first section and the front section of the second section, and detects an induced signal exceeding the reference threshold voltage in the rear section of the second section. 2. The stepping motor control circuit according to claim 1, wherein the energy of the main drive pulse is set to be low when a pattern indicating that it has been obtained is obtained for a predetermined first number of times.   The controller detects an induced signal exceeding the reference threshold voltage in the first interval and the second interval before the second interval, and detects an induced signal exceeding the reference threshold voltage in the second interval after the second interval. 2. The stepping motor control circuit according to claim 1, wherein the energy of the main drive pulse is set to be low when a pattern indicating this is continuously obtained a predetermined second number of times.   The controller detects an induced signal exceeding the reference threshold voltage in the first interval and the second interval before the second interval, and detects an induced signal exceeding the reference threshold voltage in the second interval after the second interval. An induced signal exceeding the reference threshold voltage is not detected in the second interval, the second interval, which is the number of times that the pattern indicating that this is continuously obtained, is detected in the second interval. When the pattern indicating that the induced signal exceeding the reference threshold voltage is detected in the rear section is greater than the first number of times obtained continuously, the energy of the main drive pulse is set low. The stepping motor control circuit according to claim 1, wherein:   A movement comprising the stepping motor control circuit according to any one of claims 1 to 4.   An analog electronic timepiece comprising the movement according to claim 5.

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