JP4152141B2 - Stepping motor drive control device, rotation drive device, and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drive control device for a stepping motor, a rotary drive device including the device, and an image forming apparatus such as a copying machine, a printer, and a FAX.
[0002]
[Prior art]
The stepping motor can be rotated by an angle determined according to the number of pulses of the drive pulse signal by inputting the drive pulse signal to the driver. For this reason, since the rotation control of the rotating body by the stepping motor can be easily performed without using a feedback signal, the image forming apparatus such as a copying machine or a printer is also widely used. However, while the stepping motor is easy to control, if a large torque is applied from the outside to step out even during rotation exceeding the self-starting region (during rotation in the through region), the stepping motor will step out. Unless the frequency of the drive pulse signal falls within the self-activation region, there is a drawback that normal rotation cannot be continued.
Therefore, conventionally, control has been performed to monitor whether or not the stepping motor has stepped out and to stop driving the stepping motor when the stepping out is detected (see, for example, Japanese Patent Laid-Open No. 3-293860). .
[0003]
[Problems to be solved by the invention]
However, if the stepping motor drive is stopped when the stepping motor step-out is detected as in the above-described conventional control, there is a problem that the operation of the apparatus up to that point is wasted. For example, in a color image forming apparatus equipped with a stepping motor, if the stepping motor that drives the developing roller steps out during the creation of the color image, the color image previously formed on the photoreceptor is wasted. End up.
When manufacturing devices that use stepping motors, stepping motors with sufficient margin for the above-mentioned step-out are selected on the assumption of externally applied torque. The load gradually increases and the margin for step-out disappears.
[0004]
The present invention has been made in view of the above problems. The purpose is to control the driving of the stepping motor that can prevent the normal operation of the device using the stepping motor from being interrupted and wasted due to the step-out of the stepping motor. Dress Is to provide a position. Still another object is to provide a rotary drive device and an image forming apparatus provided with such a stepping motor drive control device.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 is characterized in that the stepping detection means for detecting whether or not the stepping motor is out of step and the stepping motor immediately after turning on the power prior to the normal operation of the apparatus using the stepping motor. The motor driving condition is switched to a severe driving condition in which the stepping motor is more likely to step out than the driving condition during the normal operation, and the presence or absence of the stepping motor stepping out is detected, and the stepping motor is removed. When the detection of the presence or absence of adjustment is not completed during the warm-up operation immediately after the power is turned on, the control means for controlling the detection operation of the presence or absence of step-out of the stepping motor to be terminated halfway, Detected Stepping motor of Storage means for storing information, and during the next warm-up operation, detection of the presence or absence of step-out is continued for an untested stepping motor based on the information stored in the storage means It is.
According to a second aspect of the present invention, in the stepping motor drive control apparatus according to the first aspect, the severe driving condition is a driving condition for driving at a higher starting pulse speed than the starting pulse speed of the stepping motor during the normal operation. It is characterized by being.
According to a third aspect of the present invention, in the stepping motor drive control apparatus according to the first aspect, the slow-up is completed in a time shorter than the time required for the stepping motor to be slowed up under the harsh driving conditions during the normal operation. This is a driving condition.
According to a fourth aspect of the present invention, in the stepping motor drive control apparatus according to the first aspect, the severe driving condition is a driving condition in which the driving pulse speed is higher than the driving pulse speed of the stepping motor during the normal operation. It is characterized by being.
According to a fifth aspect of the present invention, in the stepping motor drive control device according to the first, second, third, or fourth aspect, the step-out detection operation instruction means for instructing the detection operation of the presence or absence of the step-out of the stepping motor, When instructed by the step-out detection instructing means, control is performed so as to detect whether or not the stepping motor is out of step.
According to a sixth aspect of the present invention, in the stepping motor drive control apparatus according to the first, second, third, fourth, or fifth aspect, the step-out of the stepping motor is detected under the severe driving condition. It is characterized by having an informing means for informing that it has been detected.
The invention of claim 7 is a rotary drive device comprising a stepping motor for rotationally driving the rotating body and a drive control device for controlling the drive of the stepping motor. 2, 3, 4, 5 or 6 drive control devices are used.
The invention according to claim 8 is an image forming apparatus comprising a rotating body, a stepping motor for rotationally driving the rotating body, and a drive control device for controlling the driving of the stepping motor. The drive control device according to claim 1, 2, 3, 4, 5 or 6 is used.
[0006]
The ease of occurrence of a stepping motor step-out varies depending on the driving condition of the stepping motor, and the stepping motor step-out is likely to occur more severely. For example, the stepping motor is more likely to step out as the starting pulse speed or the driving pulse speed as the driving condition is increased. Further, the stepping motor is more likely to step out as the time required for slowing up the stepping motor becomes shorter.
Therefore, claims 1 to 8 In this invention, prior to the normal operation of the apparatus using the stepping motor. Immediately after turning on the power The presence or absence of a stepping motor step-out is detected under a severe driving condition in which stepping motor step-out is more likely to occur than the driving condition during normal operation. By detecting whether or not the stepping motor is out of step, it is possible to predict whether or not the stepping motor will step out during normal operation thereafter. Therefore, based on such prediction, the stepping motor can be repaired or adjusted in advance to prevent the normal operation of the apparatus using the stepping motor from being interrupted by the stepping motor stepping out and being wasted. .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to an electrophotographic color printer (hereinafter referred to as “printer”) as an image forming apparatus will be described.
First, the overall configuration of the printer according to the present embodiment will be described with reference to FIG. Transfer sheets 201 and 202 as transfer materials are respectively stored in a first paper feed cassette 203 and a second paper feed cassette 204 as transfer material storage means. The first paper feed cassette 203 and the second paper feed cassette 204 are detachably attached to the printer body. Paper feed rollers 205 and 206 serving as paper feed means are respectively provided at one end portions of the cassettes 203 and 204. The paper feed rollers 205 and 206 are used to transfer the transfer papers 201 and 202 in the cassettes 203 and 204, respectively. It is designed to feed paper. The paper feed rollers 205 and 206 supply the transfer paper to the transfer paper transport paths 207 and 208, respectively. A registration roller pair 209 that is a rotating body is provided upstream of the transfer paper transport paths 207 and 208 in the transfer paper transport direction. A registration sensor 211 is provided downstream of the registration roller pair 209. The sensor 211 detects that the transfer sheets 201 and 202 supplied to the transfer sheet transport paths 207 and 208 have been transported to just before the pair of registration rollers 209, respectively. Output a detection signal.
[0008]
Output signals from the registration sensor 211 and the copy start switch on the operation panel are input to the main control board 500, respectively. Based on these input signals, the sheet feeding rollers 205 and 206, the registration roller pair 209, and the operations necessary for image formation are controlled. Specifically, the first and second cassettes 203 and 204 are set in the control means configured by the control board 500 and the like. When a signal from the copy start switch is input, Actuate one of 206. Then, one of the transfer papers 201 and 202 stored in the paper feed cassettes 203 and 204 is conveyed to the registration roller pair 209 through the corresponding transfer paper conveyance paths 207 and 208. When the transferred transfer paper reaches the registration sensor 211, deceleration is started. After a predetermined time, the transfer paper is stopped, and the transfer paper is waited with the transfer paper leading edge abutting against the registration roller pair 209.
[0009]
On the other hand, the four sets of image forming units 1 are constituted by a photosensitive drum 10, a liquid developing device (hereinafter referred to as "developing device") 40 using a liquid developer, and the like. A full color image can be formed by using yellow toner, magenta toner, cyan toner, and black toner used in the developing devices 40Y, 40M, 40C, and 40K of the image forming units 1Y, 1M, 1C, and 1K. These toners are produced by mixing and dispersing with a ball mill or three rolls, and further dispersing in a solvent. In particular, in this embodiment, a toner adjusted to a liquid developer having a solid content of about 20% and a high viscosity of 100 to 10,000 mPa · s is used.
[0010]
Since the four sets of image forming units 1 have the same configuration, the image forming unit 1K that uses black toner will be described below.
The image forming unit 1K includes a photosensitive drum 10K as an image carrier, a uniform charger 20K as a charging unit, a laser writing device 30 for irradiating a laser beam LB, and a wet developing unit 40K as a developing unit. . Further, the image forming unit 1K includes a static eliminator (LED) 50K as a static eliminator, a photoreceptor cleaning device 60K having a cleaning blade, and the like.
The wet developing unit 40K includes a developing roller 41K as a developer carrying member, a developing tank 42K that stores a liquid developer, a pumping roller 43K, a measuring roller 44K, and the like. The pumping roller 43K is disposed so as to be immersed in the liquid developer in the developing tank 42K. The metering roller 44K is for thinning the liquid developer pumped from the pumping roller 43K and applying it to the developing roller 41K. The liquid developer is a high-viscosity liquid developer in which toner particles as visualized particles are dispersed at a high concentration in a carrier liquid as an insulator solvent.
The intermediate transfer unit 70 includes suspension rollers 71 to 76, an intermediate transfer belt 100 as an intermediate transfer member stretched around the suspension rollers 71 to 76, a primary transfer charge applying unit, and a cleaning device 79 having a cleaning blade. Etc. In the present embodiment, primary transfer bias rollers 77K, 77Y, 77M, and 77C are provided as the primary transfer charge applying means.
The paper transfer unit 80 includes a secondary transfer bias roller 81 as a secondary transfer charge applying unit and a secondary transfer power source (not shown) connected to the secondary transfer bias roller 81.
The intermediate transfer belt 100 is stretched around a suspension roller 71 to 76 as a suspension member and the photosensitive drums 10K, 10Y, 10M, and 10C with a predetermined tension, and can be rotated counterclockwise as indicated by an arrow. . Further, the primary transfer bias roller 77K is opposed to the photosensitive drum 10K, and the intermediate transfer belt is sandwiched between the primary transfer bias roller 77K and the photosensitive drum 10K. The primary transfer bias roller 77K also serves as an electrode for applying a primary transfer bias, and a predetermined transfer bias is applied to the primary transfer bias roller 77K from a primary transfer power source (not shown). A secondary transfer bias roller 81 as a secondary transfer charge applying unit is arranged to face the suspension roller 73 and also serves as an electrode for applying a secondary transfer bias. A predetermined transfer bias is applied to the secondary transfer bias roller 81 from a secondary transfer power source (not shown).
[0011]
Next, the image forming operation of the color printer of this embodiment will be described.
As shown in FIG. 2, the photosensitive drum 10K is uniformly charged by the charger 20K while being driven to rotate in the direction of the arrow, and then a laser beam LB is irradiated from the laser writing device 30 to electrostatically charge the photosensitive drum 10K. A latent image is formed. On the other hand, the liquid developer adhering to the scooping roller 43K immersed in the high-viscosity liquid developer in the developing tank 42K is uniformly spread on the developing roller 41K via the measuring roller 44K, for example, a thickness of about 0.5 to 20 μm. It is applied. Then, the developing roller 41K is brought into contact with the photosensitive drum 10K, the toner in the liquid developer is transferred to the electrostatic latent image formed on the surface of the photosensitive drum 10K by the electric field, and the toner image is developed. Form.
Next, by rotating the photosensitive drum 10K on which the toner image is formed, the toner image on the photosensitive drum 10K moves to a primary transfer position where the photosensitive drum 10K and the intermediate transfer belt 100 abut. Then, at this primary transfer position, a negative polarity bias voltage (for example, −300 to −500 V) that is the reverse polarity of the positive polarity toner is applied to the back surface of the intermediate transfer belt 100 via the primary transfer bias roller 77K. With the electric field generated by the applied voltage, the toner of the toner image on the photosensitive drum 10K is attracted to the intermediate transfer belt 100 and transferred onto the intermediate transfer belt 100 (primary transfer). Similarly, yellow toner, magenta toner, and cyan toner are transferred to the intermediate transfer belt 100 to form a full-color image.
Next, by rotating the intermediate transfer belt 100 onto which the full-color toner image has been transferred, the transferred portion of the full-color toner image on the intermediate transfer belt 100 moves to the secondary transfer position. The transfer paper 201 or the transfer paper 202 is fed again from the registration roller pair 209 in synchronization with the movement of the full-color image on the intermediate transfer belt 100. At the secondary transfer position, a negative bias voltage (for example, −800 to −2000 V) is applied to the back surface of the transfer paper 201 or the transfer paper 202 via the secondary transfer bias roller 81, and a predetermined pressure ( For example, 50 N / cm ² Degree). The toner of the intermediate transfer belt 100 is attracted to the transfer paper 201 or the transfer paper 202 by the electric field and pressure generated by the applied voltage, and Y, M, C, and K four color toner images are collectively collected on the transfer paper 201 or the transfer paper 202. Transfer (secondary transfer).
Thereafter, the transfer paper 201 or the transfer paper 202 onto which the toner image has been transferred is separated from the adsorbing intermediate transfer belt 100 by the separating device 85, and after being subjected to fixing processing by the fixing device 90, is discharged from the apparatus main body. The
On the other hand, the surface of the photosensitive drum 10K after the primary transfer is subjected to charge removal by a neutralization device (LED) 50K, the surface is cleaned by a cleaning device 60K, untransferred toner is collected and removed, and the next image formation is performed. By repeating this, a large number of copies are made.
[0012]
Next, the configuration and control according to the characteristic part of the present invention will be described.
In the printer of this embodiment, a number of stepping motors are used for the paper feed rollers 205 and 206, the registration roller pair 209, the photosensitive drums 10Y, 10M, 10C, and 10K, and other rotational drives. Although these stepping motors are easy to control, they will step out if a large torque is applied from the outside even during a moment exceeding the self-starting frequency, and will continue to rotate normally unless it falls below the self-starting frequency. There is a disadvantage that cannot be done. For this reason, it may be too late to detect after a step-out occurs. For example, if the developing roller steps out during the creation of a color image, the color toner image previously created on the photosensitive drum is wasted. Therefore, it is necessary to predict step-out before actually creating an image. On the other hand, a stepping motor having a sufficient margin is selected at the time of production, but generally, the load gradually increases due to wear, grease consumption, etc. due to use for a long period of time, and the margin disappears.
[0013]
Therefore, in this embodiment, prior to the normal image forming operation of the apparatus using the stepping motor, the stepping motor is operated under severe driving conditions in which the stepping motor is more likely to step out than the driving conditions during the normal operation. The presence or absence of step-out is detected.
FIG. 1 is a graph showing an example of a drive pattern (P1) and a test drive pattern (P2) for step-out detection during a normal image forming operation in the printer of this embodiment. In the normal image forming operation (P1) in FIG. 1, the driving is performed by setting the starting pulse speed to 1000 PPS, the time required for slow-up to 80 msec, and the operation pulse speed to 8000 PPS.
On the other hand, at the time of test drive for out-of-step detection (P2) executed prior to the normal image forming operation, the stepping motor is driven under a severer driving condition than that during the normal image forming operation. In the example of FIG. 1, the start pulse speed is increased to 1500 PPS, the time required for slow-up is shortened to 70 msec, and the operation pulse speed is increased to 10500 PPS for driving. The stepping motor is preliminarily test-driven under such severe driving conditions that the step-out is more likely to occur than during normal image formation, and the presence or absence of the step-out of the stepping motor is detected. When stepping motor step-out is detected under such severe driving conditions, it is predicted that step-out will occur even during normal image forming operations. Exchange, adjust, etc. This can prevent the stepping motor from stepping out during normal image creation.
[0014]
FIG. 3 is an explanatory diagram showing an example of a control system that performs drive control of the stepping motor. This control system controls the driving of the stepping motor 110 that rotationally drives the registration rollers 209a and 209b. The rotation of the stepping motor 110 is transmitted to the drive receiving gears 210a and 210b attached to the rotation shafts of the registration rollers 209a and 209b via the drive gear 111 attached to the motor shaft 110a. The registration rollers 209a and 209b are rotationally driven through the drive receiving gears 210a and 210b.
[0015]
The stepping motor 110 is driven and controlled by a main control board 500 as a control means via a driver 501 as a driving power source. The drive control device for the stepping motor 110 is configured using the main control board 500 and the driver 501. Further, the drive control device and the stepping motor 110 constitute a rotation drive device that drives a rotating body such as the registration roller.
The main control board 500 includes a CPU 500a, a memory 500b as a storage unit including a RAM and a ROM, an interface unit (not shown), and the like. Then, a drive control signal (pulse signal) is input from the main control board 500 to the driver 501, and a drive current is supplied from the driver 501 to the stepping motor 110 based on the drive control signal, whereby the stepping motor 110 is rotationally driven. Is done. The driving condition of the stepping motor 110 can be switched by changing a drive control signal (pulse signal) input to the driver 501.
The main control board 500 is configured to be able to transmit and receive data to and from an operation panel 503 as an operation means. The operation panel 503 is provided with a display 503a as notification means for notifying that a step-out of the stepping motor 110 has been detected. Furthermore, an input operation unit 503b is provided as a step-out detection operation instruction means for instructing a detection operation for the presence or absence of step-out of the stepping motor 110.
[0016]
A step-out sensor 502 is attached to the motor shaft 110a of the stepping motor 110 as a step-out detection means for detecting the presence or absence of a known step-out. The step-out sensor 502 is configured by using a filler 502a attached to the motor shaft 110a and a photo interrupter 502b provided at a position where the filler 502a can be shielded from light. The filler 502a shields the optical axis of the photo interrupter every time the motor shaft 110a of the stepping motor 110 rotates once. The step-out sensor 502 is not provided in the stepping motor 110, but a filler is attached to a member that is rotationally driven by the stepping motor 110, and the optical axis of the photo interrupter 502b is blocked by moving the filler. May be.
A detection signal (output signal) from the photo interrupter 502 b of the step-out sensor 502 is input to the main control board 500. If the output signal from the step-out sensor 502 does not change even after a certain time has elapsed after the driving of the stepping motor 110 is started, it is determined that the stepping motor 110 has stepped out on the main control board 500.
[0017]
FIG. 4 is a flowchart showing an example of control in the step-out detection test drive mode executed immediately after power-on. When the printer is turned on, a warm-up operation of the fixing device 90 and the like is started (steps 1 and 2). Along with the start of the warming-up operation, the test drive of the stepping motor 110 is started under the driving condition that the step-out is more likely to occur than in the normal image forming operation (step 3). During this test drive, the presence or absence of step-out of the stepping motor 110 is detected. When the stepping motor 110 is detected to be out of step during the test drive, a warning “service man call”, that is, a warning to call a service man for repair is displayed on the display 503a of the operation panel 503 (step 4, 5). Thereby, it is possible to notify the operator that a step-out has occurred. The operator who confirms the “service man call” can contact the service man and request repair, replacement, adjustment, etc. of the stepping motor.
On the other hand, when the step-out of the stepping motor 110 is not detected during the execution of the test drive mode and the warm-up operation is completed after that, the process shifts to a standby state for the image forming operation (steps 6, 7, and 8).
[0018]
FIG. 5 is a flowchart showing another control example in the step-out detection test drive mode executed immediately after power-on.
If the test drive mode for step-out detection is performed many times a day, time is wasted. Therefore, it is desirable to perform it during warm-up of the fixing device immediately after the power is turned on. However, when the number of stepping motors used is large, the step-out detection test drive mode may not be completed during warm-up.
Therefore, in this control example, when the warm-up is completed, the step-out detection test drive mode is interrupted, and the detected stepping motor information is stored in the memory 500b in the main control board 500 (steps 6 and 7). Then, at the next warm-up, based on the information stored in the memory 500b, the test driving is performed for the stepping motor that has not been inspected, and the out-of-step detection inspection is continued.
[0019]
FIG. 6 is a flowchart showing a control example in the step-out detection test drive mode executed based on an operator instruction.
In this control example, an operator such as a serviceman operates the input operation unit 503b of the operation panel 503 to instruct the start of execution of the step-out detection test drive mode in order to pursue the cause of the printer trouble or the like ( Step 1). Based on this instruction, execution of the step-out detection test drive mode is started (step 2). When stepping motor step-out is detected, a message indicating that a service man call or step-out has been detected is displayed (steps 3 and 4).
[0020]
As described above, according to the present embodiment, before the normal image forming operation, the stepping motor 110 is stepped out under a severe driving condition in which the stepping motor is likely to step out more than the driving condition during the normal image forming operation. The presence or absence of is detected. By detecting whether or not the stepping motor 110 has stepped out, it can be predicted whether or not the stepping motor will step out during the subsequent normal image forming operation. Therefore, based on such prediction, repair or adjustment of the stepping motor 110 is performed in advance by contacting a service person or the like, and the normal image forming operation is interrupted due to step-out of the stepping motor 110 and is wasted. Can be prevented.
In addition, according to the present embodiment, at the time of the step-out detection, at least one of the start pulse speed, the operation pulse speed, and the time required for the slow-up that easily affects the occurrence of the step-out of the stepping motor is set to a severe driving condition. Switching. Therefore, it can be predicted more reliably whether or not the stepping motor will step out.
Further, according to the present embodiment, the presence or absence of the stepping motor is detected immediately after the power is turned on, so the control for detecting the presence or absence of the step-out is completed during the warm-up immediately after the power is turned on. be able to. Therefore, it is not necessary to individually set the time only for executing the control for detecting the presence or absence of the step-out. Even when the time for executing the control for detecting the presence / absence of the step-out takes longer than the warm-up time immediately after the power is turned on, a part of the warm-up time can be used.
Further, according to the present embodiment, when the detection of the presence or absence of the stepping motor step-out is not completed during the warm-up operation immediately after the power is turned on, the stepping motor step-out detection operation is terminated halfway. May be. In this case, even when the time for executing the control for detecting the presence / absence of the step-out takes longer than the warm-up time immediately after the power is turned on, the control for detecting the presence / absence of the step-out is performed only. There is no need to set the time individually.
In this case, information on the state where the detection of the presence or absence of the stepping motor step-out has been completed may be stored in the memory 500b of the main control board 500. In this case, during the next warm-up, based on the information stored in the memory 500b, the stepping motor that has not been inspected can be test-driven to continue the step-out detection inspection. Accordingly, it is possible to avoid the redundant inspection of the inspected stepping motor that has been inspected during the previous warm-up, and to efficiently perform the step-out detection inspection of the stepping motor.
Moreover, according to this embodiment, the detection operation of the presence or absence of step-out of the stepping motor can be executed based on an instruction from an operator such as a service person. Therefore, it is possible to assist the operator such as a service person in pursuing the cause of the drive system trouble that has occurred in the printer.
In addition, according to the present embodiment, when the stepping motor out of step is detected under the severe driving conditions, it is informed that the out of step has been detected, so contact the service person, The operator can be prompted to repair, replace, or adjust the stepping motor.
[0021]
In the above-described embodiment, the case where the registration roller is rotationally driven by the stepping motor has been described. However, the present invention can also be applied to the case where the rotary body such as the photosensitive drum and the developing roller is rotationally driven by the stepping motor. Is.
The present invention is not limited to a wet type electrophotographic printer using a liquid developer, and other image forming apparatuses such as a dry type electrophotographic printer, a copying machine, and a FAX, as long as a stepping motor is used. It can also be applied to.
The present invention is not limited to the image forming apparatus, and can be applied to various apparatuses other than the image forming apparatus as long as a stepping motor is used.
[0022]
【The invention's effect】
Claims 1 to 8 According to the invention of Immediately after turning on the power By detecting whether or not the stepping motor has stepped out under severe driving conditions, it is possible to predict whether or not the stepping motor will step out during normal operation thereafter. Therefore, based on this prediction, repair, replacement, adjustment, etc. of the stepping motor is performed in advance to prevent the normal operation of the device using the stepping motor from being interrupted and wasted due to the stepping motor stepping out. There is an effect that can be.
[Brief description of the drawings]
FIG. 1 is a graph showing an example of a drive pattern (P1) and a test drive pattern (P2) for step-out detection during a normal image forming operation in a printer according to an embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of the printer.
FIG. 3 is an explanatory diagram illustrating an example of a control system that performs drive control of a stepping motor of the printer.
FIG. 4 is a flowchart showing an example of control in a step-out detection test drive mode executed immediately after power-on.
FIG. 5 is a flowchart showing another control example in a step-out detection test drive mode executed immediately after power-on.
FIG. 6 is a flowchart showing another control example in the step-out detection test drive mode;
[Explanation of symbols]
110 Stepping motor
209 (a, b) Registration roller (rotating body)
500 Main control board
500a CPU
500b memory
501 driver
502 Step-out sensor
502a filler
502b Photo interrupter
503 Operation panel
503a display
503b Input operation unit

Claims (8)

A step-out detecting means for detecting whether or not the stepping motor has stepped out;
Immediately after turning on the power prior to the normal operation of the device using the stepping motor, the driving condition of the stepping motor is switched to a severe driving condition in which the stepping motor is more likely to step out than the driving condition during the normal operation. Detecting the presence or absence of step out of the stepping motor, and detecting the presence or absence of step out of the stepping motor is not completed during the warm-up operation immediately after turning on the power. Control means for controlling to end in the middle,
And storage means for storing the information of the detection already stepping motor,
A drive control device for a stepping motor, wherein during the next warm-up operation, detection of the presence or absence of step-out is continued for an untested stepping motor based on information stored in the storage means. In the stepping motor drive control apparatus according to claim 1,
The stepping motor drive control apparatus, wherein the severe driving condition is a driving condition for driving at a starting pulse speed higher than the starting pulse speed of the stepping motor during the normal operation. In the stepping motor drive control apparatus according to claim 1,
The stepping motor drive control apparatus, wherein the severe driving condition is a driving condition in which the slow-up is completed in a time shorter than a time required for the slow-up of the stepping motor in the normal operation. In the stepping motor drive control apparatus according to claim 1,
The stepping motor drive control apparatus, wherein the severe driving condition is a driving condition for driving at an operation pulse speed higher than an operation pulse speed of the stepping motor during the normal operation. In the stepping motor drive control device according to claim 1, 2, 3, or 4,
A step-out detection operation instruction means for instructing a detection operation of the presence or absence of step-out of the stepping motor;
A stepping motor drive control device, characterized in that, when instructed by the step-out detection instructing means, control is performed to detect whether or not the stepping motor is out of step. In the stepping motor drive control device according to claim 1, 2, 3, 4 or 5,
A stepping motor drive control apparatus, comprising: a notifying means for notifying that a step-out of the stepping motor has been detected under the severe driving conditions. A rotary drive device comprising a stepping motor for rotationally driving a rotating body, and a drive control device for controlling the drive of the stepping motor,
A rotary drive device using the drive control device of claim 1, 2, 3, 4, 5 or 6 as the drive control device. An image forming apparatus comprising: a rotating body; a stepping motor for rotationally driving the rotating body; and a drive control device for controlling driving of the stepping motor,
7. An image forming apparatus using the drive control device according to claim 1, 2, 3, 4, 5, or 6 as the drive control device.

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