JP4209721B2 - Stepping motor driving apparatus and method, and stepping motor apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stepping motor drive apparatus and method, and a stepping motor apparatus, and more particularly to a stepping motor that generates a rotational torque by supplying a plurality of periodic drive signals having different phases. The present invention relates to a driving apparatus and method, and a stepping motor apparatus.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, a vehicular indicating device is known as a device using the above-described stepping motor driving device. In this pointing device, the measured values measured by various sensors are pointed by a pointer, and a stepping motor is used as a movement for driving the pointer.
[0003]
The driving device for driving the stepping motor rotates the stepping motor in accordance with a movement amount (θ−θ ′) that is a difference between the current position θ ′ of the pointer and the target position θ. As a result, the pointer moves by an amount of movement (θ−θ ′) to indicate the target position θ. The target position θ is updated to the angle data θi every time the angle data θi calculated based on the measurement values measured by various sensors is input.
[0004]
In addition, the drive device supplies periodic drive signals having different phases, and periodically changes the excitation state of the excitation coil inside the stepping motor, whereby rotational torque is applied to the magnet rotor surrounded by the excitation coil. Generate and rotate the stepping motor.
[0005]
By the way, the movement amount (θ−θ ′) to which the pointer should move differs from the actual movement amount due to the input of the angle data θi on which the vibration or noise of the vehicle is superimposed. There was a case where step-out occurred. If this step-out is repeated, an error occurs between the measured value indicated by the pointer and the measured value measured by the various sensors, and it becomes impossible to give an accurate instruction.
[0006]
Therefore, in order to solve such a problem, a stepping motor is provided with a piece as a driven member that is interlocked with the rotation, and a stopper that mechanically stops the rotation of the stepping motor by contacting the piece. Provide. This stopper is provided so that the pointer indicates the measured value 0 when it comes into contact with the piece.
[0007]
Then, for example, each time the power is turned on, the drive device rotates the stepping motor so that the piece is directed to the stopper side, and the piece is forcibly brought into contact with the stopper, thereby forcing the pointer. The initialization operation to stop at the measured value 0 is performed.
[0008]
By performing the above initialization operation, when the current position θ ′ is recognized as the measurement value 0, the pointer also actually indicates the measurement value 0. Therefore, the measurement value indicated by the pointer, The error between the measured values measured by various sensors could be reset.
[0009]
However, the above-described indicating device needs to rotate the piece by, for example, 360 ° in order to reliably bring the piece into contact with the stopper. For this reason, a state occurs in which the excitation state of the excitation coil in the stepping motor continues to change periodically in a state where the piece abuts against the stopper and the stepping motor cannot rotate further in the stopper direction.
[0010]
In such a state, while the excitation state of the excitation coil changes for one cycle, the stepping motor alternately generates rotational torque in the direction toward the stopper and rotational torque in the direction away from the stopper. As a result, there is a problem in that the pieces abut against the stopper, or the pieces are repeatedly rebounded away from the stopper 1e, and the appearance during the initialization operation is poor.
[0011]
In order to solve such a situation, Patent Document 1 discloses that a drive signal that skips a phase range in which rotational torque in a direction away from the stopper is generated is supplied to prevent rebound. However, when the phase range is extremely skipped as described above, there is a problem that the magnet rotor cannot follow the excitation change of the excitation coil when the step-out actually occurs. Is difficult.
[0012]
In addition, while the piece is not in contact with the stopper by the initialization operation and the stepping motor can rotate, an induced voltage is generated in the non-excited coil, while the piece comes into contact with the stopper and the stepping motor rotates. When stopping, pay attention to the fact that no induced voltage is generated in the coil. Based on the presence or absence of the induced voltage generated in the non-excited coil, the rotation of the stepping motor is stopped when it is detected that the piece is in contact with the stopper. Things were considered.
[0013]
However, in this case, additional components such as a comparator and an A / D converter are required to detect the induced voltage, which is problematic in terms of cost. In addition, since the magnet rotor is small in a small stepping motor, there is a problem that the measurable induced voltage is low, the difference in induced voltage during rotation and contact is small, and the S / N ratio is not good.
[0014]
[Patent Document 1]
JP-A-8-247795
[Problems to be solved by the invention]
Accordingly, the present invention provides a stepping motor driving apparatus and method, and a stepping motor apparatus that can perform initialization operation in a low-cost, surely, and suppressably rebounding , paying attention to the above-described problems. This is the issue.
[0016]
[Means for Solving the Problems]
The invention according to claim 1, which has been made to solve the above-described problem, is a stepping motor drive device that generates a rotational torque in a stepping motor by supplying a plurality of periodic drive signals having different phases. , rotational torque generated at the stepping motor when it is supplying a predetermined phase range of one period of the drive signal, so that the smaller than the rotational torque generated at the stepping motor when supplied the remaining phase range The first driving means for supplying the driving signal and the control means for supplying the driving signal to the first driving means at the time of the initialization operation in which the driven member interlocked with the rotation of the stepping motor is brought into contact with the stopper. When, wherein the predetermined phase range, wherein said driven member in a state in which the driven member is in contact with the stopper the A phase range is set so as to include a phase range in which the rotational torque in the forward rotation direction in which the driven member moves away from the stopper when the drive signal in the reverse rotation direction toward the topper is generated is generated in the stepping motor. The phase range is such that the rotation torque in the reverse direction is generated in the stepping motor when the drive signal in the reverse direction is continuously supplied with the driven member in contact with the stopper. It exists in the drive device of the stepping motor characterized by setting so that it may be included.
[0017]
A fourth aspect of the present invention is a stepping motor driving method for generating a rotational torque in a stepping motor by supplying a plurality of periodic driving signals having different phases, and interlocks with the rotation of the stepping motor. the stepping when the rotation torque generated at the stepping motor when supplying a predetermined phase range of one period of the drive signal during the initialization operation is brought into contact with the driven member on the stopper has, that supplied the remaining phase range The driving signal is supplied such that the driving torque is smaller than the rotational torque generated in the motor, and the predetermined phase range is set in a reverse direction in which the driven member faces the stopper while the driven member is in contact with the stopper. When the drive signal continues to be supplied, the rotational torque in the forward direction in which the driven member moves away from the stopper is The phase range is set to include a phase range that occurs in a stepping motor, and the remaining phase range is the reverse rotation when the driven member continues to supply the drive signal in the reverse direction with the stopper being in contact with the stopper. The stepping motor driving method is characterized in that the rotational torque in the direction is set so as to include the entire phase range that occurs in the stepping motor.
[0018]
According to a fifth aspect of the present invention, a stepping motor, a driven member that interlocks with the rotation of the stepping motor, a stopper that mechanically stops the driven member, and a plurality of periodic drive signals having different phases are provided. by supplying the a stepping motor apparatus and a driving device for generating rotational torque to the stepping motor, the stepping motor when it is supplying a predetermined phase range of one period of the drive signal rotational torque to be generated, the remaining such that less than the rotational torque which the generated stepper motor when supplying phase range, a first driving means for supplying the driving signal, in conjunction with the rotation of the stepping motor to be During the initialization operation in which the drive member is brought into contact with the stopper, the first drive means is supplied with the drive signal. And means, wherein the predetermined phase range, said driven member when the driven member is continued to supply a drive signal in the reverse direction toward the stopper in a state in which the driven member is in contact with the stopper Is set to include a phase range in which the rotational torque in the forward rotation direction away from the stopper is generated in the stepping motor, and the remaining phase range is set in a state where the driven member is in contact with the stopper. A stepping motor drive apparatus characterized by being set so as to include the entire phase range in which the rotational torque in the reverse rotation direction is generated in the stepping motor when the drive signal in the reverse rotation direction is continuously supplied. .
[0019]
According to the first, fourth, and fifth aspects of the present invention, when the predetermined phase range of the drive signal is supplied during the initialization operation, the rotational torque generated in the stepping motor supplies the remaining phase range. A drive signal is supplied to the stepping motor so as to be smaller than the rotational torque generated in the step.
[0020]
In addition, the predetermined range is set to include a phase range in which the rotation torque in the forward direction is generated in the stepping motor when the drive member in the reverse direction is continuously supplied with the driven member in contact with the stopper. Therefore, in the normal rotation direction, that is, in the phase range where the rotational torque is generated in the direction in which the driven member bounces off from the stopper, the rotational torque is small, so the speed of reversing from the reverse direction to the normal direction is slow and unnoticeable. The rebound of the driven member can be suppressed.
[0021]
Further, the remaining phase range includes the entire phase range in which the rotational torque in the reverse direction is generated in the stepping motor when the drive signal in the reverse direction is continuously supplied with the driven member in contact with the stopper. Therefore, since a large rotational torque is generated in all the phase ranges in which the rotational torque is generated in the reverse rotation direction, that is, the direction in which the driven member is pressed against the stopper, the rebound of the driven member can be further suppressed. .
[0025]
According to a second aspect of the invention, a driving apparatus for stepping motor according to claim 1, the second driving hands stage for supplying the driving signals such as rotational torque is always constant generated in the stepping motor In addition, the control means may be a stepping motor drive device that causes the second drive means to supply the drive signal during a normal operation other than the initialization operation.
[0026]
According to the second aspect of the invention, the second driving means, such as rotating torque generated at the stepping motor becomes constant at all times, and supplies a drive signal. The control means causes the second drive means to supply a drive signal during a normal operation other than the initialization operation.
[0027]
Accordingly, by causing the second drive means to supply a drive signal during normal operation, a constant rotational torque is generated during normal operation. Therefore, the rotation speed of the stepping motor increases or decreases during one cycle. There is nothing to do.
[0028]
According to a third aspect of the invention, a driving apparatus for a stepping motor according to claim 2, wherein said initializing operation is performed for each power-up, the control unit, the power-on every start, the storage medium The recorded current position of the driven member is read, the drive signal is supplied to the second drive means according to the difference between the read current position and the stopper position, and then the first drive means The stepping motor driving apparatus is characterized in that the driving signal is supplied to the stepping motor.
[0029]
According to the third aspect of the present invention, the current position of the driven member recorded in the storage medium is read every time the power is turned on, and the second position is determined according to the difference between the read current position and the stopper position. The drive signal is supplied to the drive means, and then the drive signal is supplied to the first drive means. Therefore, when the difference between the current position of the driven member and the stopper position is large, such as when the power supply is momentarily interrupted, the stepping motor can be quickly rotated by using the drive signal supplied by the second driving means by the difference. it can.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an indicating device incorporating a driving device that implements the stepping motor driving method of the present invention. The instruction device (= stepping motor device) includes a stepping motor 1, a pointer 2 driven by the stepping motor 1, and a drive device 3 that controls the rotation of the stepping motor 1. The above-described stepping motor 1 includes two excitation coils 1a1 and 1a2 and NS poles alternately magnetized in three poles, a magnet rotor 1b that rotates following changes in the excitation state of the excitation coils 1a1 and 1a2, and a magnet A gear 1c that transmits the driving force of the rotor 1b to the pointer 2 is provided.
[0031]
Further, the stepping motor 1 is provided on the back side of the gear 1c on the pointer 2 side, and a piece 1d as a driven member interlocked with the rotation of the magnet rotor 1b, the excitation coils 1a1 and 1a2, the magnet rotor 1b, the gear 1c, A stopper 1e is provided in a housing case (not shown) for housing the piece 1d, and mechanically stops the rotation of the magnet rotor 1b by contacting the piece 1d. The stopper 1e is provided so that the pointer 2 indicates the scale of the measured value 0 on the dial when it comes into contact with the piece 1d.
[0032]
Hereinafter, the rotation direction of the stepping motor 1 in which the piece 1d faces the stopper 1e is defined as the reverse rotation direction. On the other hand, the rotation direction of the stepping motor 1 such that the piece 1d is separated from the stopper 1e is defined as a normal rotation direction.
[0033]
The drive device 3 described above stores a central processing unit (CPU) 3a that performs various processes and controls in accordance with a predetermined program, a ROM 3b that is a read-only memory that stores programs for the CPU 3a, and various data. At the same time, it is composed of a μCOM incorporating a RAM 3c, which is a readable / writable memory having an area necessary for processing operations of the CPU 3a.
[0034]
Excitation coils 1 a 1 and 1 a 2 in the stepping motor 1 are connected to a driving device 3. Then, upon receiving the periodic drive signal output from the drive device 3, the excitation states of the respective excitation coils 1a1 and 1a2 change periodically, and rotational torque is generated in the magnet rotor 1b. Further, the drive device 3 described above starts to be turned on when the ignition switch is turned on, for example.
[0035]
During the initialization operation, the driving device 3 reversely rotates the stepping motor 1 to forcibly bring the piece 1d into contact with the stopper 1e. The drive signal A supplied by the drive device 3 during this initialization operation will be described with reference to FIG. FIG. 5A is a graph showing the relationship between the phase φ of the drive signal A and the rotational torque T generated in the stepping motor 1.
[0036]
As shown in the figure, when the drive device 3 supplies the phase range R ₁ (= predetermined phase range) of the drive signal A, the rotational torque T generated in the stepping motor 1 is changed to the phase range R ₂ (= the remaining range). When the phase range is supplied, the drive signal A is supplied so as to be, for example, half the rotational torque T generated in the stepping motor 1. At this time, COS current and SIN current in which the amplitude of the phase range R ₁ is half the amplitude of the phase range R ₂ flow through the exciting coils 1a1 and 1a2, respectively, as shown in FIG.
[0037]
By the way, if the drive signal A in the reverse rotation direction is continuously supplied with the piece 1d in contact with the stopper 1e, as shown in FIG. 2B, the rotation torque in the reverse rotation direction (in the drawing) Reverse rotation torque) and rotational torque in the forward direction (forward rotation torque in the figure) are alternately generated. Thereby, the piece 1d comes into contact with the stopper 1e, or the rebounding of the piece 1d away from the stopper 1e is repeated alternately.
[0038]
Therefore, in the present invention, the phase range R ₁ in which the small rotational torque is generated includes the phase range in which the forward rotation torque is generated, and the phase in which the reverse rotation torque is generated in the phase range R ₂ in which the large rotational torque is generated. Each phase range R ₁ and R ₂ is set so as to include the range.
[0039]
If the drive signal A in the reverse direction is supplied to the stepping motor during the initialization operation, the stepping motor 1 is in the normal rotation direction, that is, in the phase range R ₁ in which the rotational torque in the direction in which the piece 1d rebounds from the stopper 1e is generated. Therefore, the reversal speed from the reverse rotation direction to the normal rotation direction becomes slow and conspicuous, and the rebound of the piece 1d can be suppressed.
[0040]
Further, in the reverse rotation direction, that is, in the phase range R ₂ in which the rotational torque in the direction in which the piece 1d is pressed against the stopper 1e is generated, a large rotational torque is generated, so that the bounce of the piece 1d can be further suppressed. Therefore, even if the induced voltage is not detected, the rebound of the driven member can be suppressed, and the initialization operation can be performed reliably, inexpensively, and with good appearance.
[0041]
Furthermore, since a large rotational torque is generated when the phase range R ₂ is being supplied, the piece 1d can be quickly directed to the stopper 1e when a step-out occurs. As is clear from the above, when the drive signal A is supplied, the drive device 3 functions as the first drive means.
[0042]
On the other hand, during normal operation, the driving device 3 rotates the stepping motor 1 in accordance with a movement amount (θ−θ ′) that is a difference between the current position θ ′ of the pointer 2 and the target position θ. As a result, the pointer 2 moves by an amount of movement (θ−θ ′) to indicate the target position θ. The target position θ is updated to the angle data θi every time the angle data θi calculated based on the measurement values measured by various sensors is input.
[0043]
Next, the drive signal B supplied by the drive device 3 during normal operation will be described with reference to FIG. FIG. 5A is a graph showing the relationship between the phase φ of the drive signal B and the rotational torque T generated in the stepping motor 1. As shown in the figure, the drive device 3 supplies a drive signal B such that the rotational torque T generated in the stepping motor 1 is always constant. At this time, a constant amplitude COS current and SIN current shown in FIG. 4B flow through the exciting coils 1a1 and 1a2, respectively.
[0044]
In this way, during the normal operation where it is not necessary to consider the bounce at the stopper 1e, the rotation speed of the stepping motor 1 can be increased within one cycle of the drive signal by supplying the drive signal with the rotation torque T being always constant. Since it does not become faster or slower, normal operation can be performed quickly and nicely.
[0045]
The details of the initialization operation outlined above will be described below with reference to the flowchart shown in FIG.
The CPU 3a starts an initialization operation when power-on from the in-vehicle battery is started, and first reads the current position θ ′ of the pointer 2 stored in the RAM 3c (= storage medium) (step S1). The current position θ ′ of the pointer 2 naturally corresponds to the current position of the piece 1d.
[0046]
The RAM 3c is non-volatile that retains its contents even when the power is shut off. For this reason, if the power-on start is due to a return from a state in which power-on to the driving device 3 is temporarily interrupted in response to the engine start, the current position θ ′ stored in the RAM 3c is The indicated position of the pointer 2 before being temporarily interrupted is stored.
[0047]
Next, the CPU 3a supplies the drive signal B in the reverse direction to the stepping motor 1 by an amount corresponding to the difference (−θ ′) between the read current position θ ′ and the initial position 0 ° (= stopper position) ( Step S2). By the processing in step S2, the piece 1d and the pointer 2 rotate by −θ ′.
[0048]
When the output of the drive signal B is completed, the CPU 3a supplies the drive signal A in the reverse direction to the stepping motor 1 (step S3). By the processing in step S3, the pointer 2 rotates toward the measured value 0, and the piece 1d rotates toward the stopper 1e. Next, the CPU 3a waits for the piece 1d to rotate 360 ° (Y in step S4), stops supplying the drive signal A, and ends the process.
[0049]
As is clear from the above, the CPU 3a functions as a control means. Further, according to the above instruction device, the difference between the current position of the piece 1d and the position of the stopper 1e before the power-on is cut off due to the engine start, and the piece 1d using the drive signal B at high speed. It is rotating. Further, after returning the piece 1d to the position of the stopper 1e or near the position using the high-speed drive signal B, the stepping motor uses the drive signal A that is slower than the drive signal B but can suppress the rebound. Since 1 can be rotated, the initialization operation can be performed quickly.
[0050]
In the embodiment described above, the rotational torque T generated in the stepping motor 1 when the phase range R ₁ of the drive signal A is supplied is the rotational torque T generated in the stepping motor 1 when the phase range R ₂ is supplied. In contrast, the driving signal A is supplied so as to be halved uniformly. Further, the phase range R ₁ includes the entire phase range in which the forward rotation torque is generated.
[0051]
However, for example, it is conceivable to output a drive signal A as shown in FIG. That is, the rotational torque T generated in the stepping motor 1 when the phase range R ₁ is supplied may be uniformly reduced with respect to the rotational torque T generated in the stepping motor 1 when the phase range R ₂ is supplied. Need not be. Further, the phase range R ₁ may include only a part of the phase range in which the forward rotation torque is generated. It is also conceivable to supply a drive signal A as shown in FIG.
[0052]
【The invention's effect】
As described above, according to the first, fourth, and fifth aspects of the invention , the rotational torque is small in the normal rotation direction, that is, in the phase range in which the rotational torque is generated in the direction in which the driven member bounces off the stopper. The speed of reversing from the reverse rotation direction to the normal rotation direction becomes slow and unnoticeable, and the rebound of the driven member can be suppressed. In addition, since a large rotational torque is generated in the entire reverse phase direction, that is, in the phase range in which the rotational torque in the direction of pressing the driven member against the stopper is generated, the rebound of the driven member can be further suppressed . It is possible to obtain a stepping motor driving apparatus and method, and a stepping motor apparatus that can perform an initialization operation surely and with good appearance.
[0055]
According to the second aspect of the present invention, since a constant rotational torque is generated during the normal operation by causing the second drive means to supply the drive signal during the normal operation, the rotation of the stepping motor during one cycle. Since the speed does not increase or decrease, it is possible to obtain a stepping motor drive device that can perform normal operation quickly and with good appearance.
[0056]
According to the third aspect of the present invention, when the difference between the current position of the driven member and the stopper position is large, such as when the power supply is momentarily interrupted, the difference is quickly made using the drive signal supplied by the second driving means. In addition, since the stepping motor can be rotated, a stepping motor drive device that can perform the initialization operation quickly can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram showing an indicating device incorporating a driving device that implements the stepping motor driving method of the present invention.
2A is a graph showing the relationship between the phase φ of the drive signal A and the rotational torque generated in the stepping motor 1. FIG. (B) is a time chart which shows the coil current which flows into exciting coil 1a1, 1a2 when the drive signal A shown to (a) is supplied to a stepping motor.
3A is a graph showing the relationship between the phase φ of the drive signal B and the rotational torque generated in the stepping motor 1. FIG. (B) is a time chart which shows the coil current which flows into exciting coil 1a1, 1a2 when the drive signal B shown to (a) is supplied to a stepping motor.
FIG. 4 is a flowchart showing a processing procedure of the CPU 3a in the initialization operation.
FIG. 5A is a graph showing the relationship between the phase φ of the drive signal A and the rotational torque generated in the stepping motor 1 in another embodiment. (B) is a time chart showing a coil current flowing in the exciting coils 1a1 and 1a2 when the drive signal A shown in (a) is supplied to the stepping motor.
FIG. 6 is a graph showing the relationship between the phase φ of the drive signal A and the rotational torque generated in the stepping motor 1 in another embodiment.
[Explanation of symbols]
1 Stepping motor 1d piece (driven member)
1e Stopper 3 Driving device (first driving means, second driving means)
3a CPU (control means)
3c RAM (storage medium)
R ₁ phase range (predetermined phase range)
R ₂ phase range (remaining phase range)

Claims (5)

A stepping motor drive device that generates a rotational torque in a stepping motor by supplying a plurality of periodic drive signals having different phases from each other,
Rotating torque generated at the stepping motor when it is supplying a predetermined phase range of one period of the drive signal, such as smaller than the rotational torque which the generated stepper motor when supplied the remaining phase range First driving means for supplying the driving signal;
Control means for supplying the drive signal to the first drive means during an initialization operation in which a driven member interlocked with the rotation of the stepping motor is brought into contact with a stopper;
The predetermined phase range is such that the driven member is separated from the stopper when the driven member continues to supply a drive signal in the reverse direction toward the stopper in a state where the driven member is in contact with the stopper. The rotational torque in the rolling direction is set to include a phase range that is generated in the stepping motor,
The remaining phase range is a phase range in which the rotational torque in the reverse direction is generated in the stepping motor when the drive member in the reverse direction is continuously supplied with the driven member in contact with the stopper. A stepping motor drive device characterized by being set to include all of them . The stepping motor drive device according to claim 1 ,
Further comprising a second driving hands stage for supplying the driving signals such as rotational torque is always constant generated in the stepping motor,
The stepping motor drive device, wherein the control means causes the second drive means to supply the drive signal during a normal operation other than the initialization operation. A stepping motor drive device according to claim 2 ,
The initialization operation is performed every time the power is turned on,
The control means reads the current position of the driven member recorded in a storage medium every time the power is turned on, and performs the second driving according to the difference between the read current position and the stopper position. A driving device for a stepping motor, wherein the driving signal is supplied to a first driving means, and then the driving signal is supplied to the first driving means. A stepping motor drive method for generating rotational torque in a stepping motor by supplying a plurality of periodic drive signals having different phases from each other,
Rotating torque generated at the stepping motor when supplying a predetermined phase range of one period of the drive signal to the driven member interlocked with the rotation of the stepping motor at the time of initialization operation to abut against the stopper, the remaining phase range smaller than the rotational torque generated at the stepping motor when supplied, supplying the drive signal,
The predetermined phase range is such that the driven member is separated from the stopper when the driven member continues to supply a drive signal in the reverse direction toward the stopper in a state where the driven member is in contact with the stopper. The rotational torque in the rolling direction is set to include a phase range that is generated in the stepping motor,
It is set to include the entire phase range in which the rotational torque in the reverse direction is generated in the stepping motor when the driven member continues to supply the reverse direction drive signal in contact with the stopper. the driving method of the stepping motor, characterized by that. A stepping motor, a driven member that interlocks with the rotation of the stepping motor, a stopper that mechanically stops the driven member, and a plurality of periodic drive signals having different phases, thereby supplying the stepping motor a driving device for generating rotational torque, a stepping motor device provided with a by a,
Rotating torque generated at the stepping motor when it is supplying a predetermined phase range of one period of the drive signal, such as smaller than the rotational torque which the generated stepper motor when supplied the remaining phase range First driving means for supplying the driving signal;
Control means for supplying the drive signal to the first drive means during an initialization operation in which a driven member interlocked with the rotation of the stepping motor is brought into contact with a stopper;
The predetermined phase range is such that the driven member is separated from the stopper when the driven member continues to supply a drive signal in the reverse direction toward the stopper in a state where the driven member is in contact with the stopper. It is set so as to include a phase range in which the rotational torque in the rolling direction is generated in the stepping motor,
The remaining phase range is a phase range in which the rotational torque in the reverse direction is generated in the stepping motor when the drive member in the reverse direction is continuously supplied with the driven member in contact with the stopper. A stepping motor drive device characterized by being set to include all of them .

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