JP2010220434A - Motor controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor controller by which the number of signal lines to transmit signals can be made less when a plurality of motors are controlled. <P>SOLUTION: FG signals, ACC signals and DEC signals are transmitted through one signal line, respectively, by alternatively transmitting signals of a first motor 403 and signals of a second motor 404 in time division. The FG 1 signal and the FG 2 signal have different voltage levels in order that an ACC/DEC module 220 discriminates the FG 1 signal and the FG 2 signal. The ACC/DEC module 220 compares a frequency of the FG signals from the motor with that of the FG signals at the target speed. In the ACC/DEC module 220, the ACC signals are accelerated by outputting only the difference when the motor speed is slower than the target speed, and the DEC signals are decelerated by outputting only the difference when the motor speed is faster than the target speed inversely. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a motor control device including a motor unit and a control unit.

  Conventionally, in an LBP (laser beam printer) and a copying machine, a DC brushless motor is used for every application because of its high rotational stability and long life. In particular, in color image forming apparatuses, DC brushless motors are increasingly used from the viewpoint of high torque and high rotational speed.

  When a highly accurate technique is required, an independent motor may be used for each color drum or developing device. In the DC brushless motor, a control board is provided for each motor. For this reason, when the number of motors increases, the size and cost of the apparatus increase. As a solution, it has been proposed to control a plurality of motors with a single drive circuit (see Patent Document 1).

JP 2003-202719 A

  However, the conventional motor control device has the following problems. That is, when a plurality of motors are controlled by a single board, the number of control signals to be input / output to the board body on which the motors are mounted increases as the number of motors to be driven increases.

  Recently, it has become possible to control the acceleration (acceleration) / dexel (deceleration) of a DC brushless motor, and the number of control signals has increased.

  Such an increase in the number of control signals causes not only an increase in cost due to the addition of signal lines, but also a problem that the size of the substrate becomes large due to the change of the pattern in the substrate.

  Therefore, the present invention can reduce the number of signal lines for transmitting signals when controlling a plurality of motors, and can reduce the size and cost of a motor unit provided with a substrate. An object is to provide a control device.

  In order to achieve the above object, a motor control device of the present invention is a motor control device including a motor unit and a control unit, wherein the motor unit detects a plurality of motors and rotations of the plurality of motors, respectively. A plurality of detection means for outputting a detection signal according to a rotation speed; and a drive means for performing speed control on each of the plurality of motors according to a control signal for each of the motors. Control means for generating a control signal for each motor based on the detected detection signal for each motor and outputting the control signal to the drive means is provided between the motor part and the control part. A detection signal is transmitted through a common detection signal line, or a control signal for each motor is transmitted through a common control signal line.

  According to the motor control device of the first aspect of the present invention, the detection signal for each motor is transmitted through the common detection signal line between the motor unit and the control unit, or the control signal for each motor is controlled in common. It is transmitted on the signal line. Thus, when controlling a plurality of motors, the number of signal lines for transmitting signals can be reduced, and the motor unit provided with the substrate can be reduced in size and cost. Further, by sharing the signal lines for the detection signal and the control signal for each motor, the number of signal lines can be reduced and the pattern on the motor board can also be reduced.

  According to the motor control device of the second aspect, when an acceleration signal and a deceleration signal are used as control signals, the number of signal lines can be reduced.

  According to the motor control apparatus of the third aspect, the number of input detection signals is counted and an acceleration signal or a deceleration signal having a pulse width corresponding to the counted value is output. Can be generated.

  According to the motor control device of the fourth aspect, the rotation of the plurality of motors is detected by detecting the rotation of the plurality of detected members that rotate in synchronization with each of the plurality of rotation bodies. It is possible to accurately control the rotation speed of the.

  According to the motor control device of the fifth aspect, since the detection signals are transmitted in time division for each motor, one detection signal line for a plurality of detection signals can be used regardless of the number of motors. .

  According to the motor control device of the sixth aspect, since the control signals are transmitted in time division for each motor, a single control signal line for a plurality of control signals can be used regardless of the number of motors. .

  According to the motor control device of the seventh and eighth aspects, since the output voltage is different for each motor, the signal for each motor can be easily identified.

  According to the motor control device of the ninth aspect, since the output voltage of the detection signal can be single by changing the duty ratio of the pulse width of the detection signal for each motor, the power supply circuit is simplified.

1 is a diagram illustrating a schematic internal configuration of a color image forming apparatus according to a first embodiment. FIG. 3 is a block diagram illustrating a configuration of a control unit in the image forming apparatus. It is a figure which shows the specific structure of a motor control apparatus. It is a block diagram which shows the schematic structure of the whole motor control apparatus. It is a timing chart which shows change of each signal in speed control of a DC brushless motor. It is a timing chart which shows speed control of the DC brushless motor performed by a time division. It is a timing chart which shows change of each signal in speed control of a DC brushless motor performed by time division. It is a timing chart which shows change of FG signal in speed control of a DC brushless motor in a 2nd embodiment.

  An embodiment of a motor control device of the present invention will be described with reference to the drawings. The motor control apparatus of this embodiment is applied to a color image forming apparatus.

[First Embodiment]
FIG. 1 is a diagram showing a schematic configuration inside a color image forming apparatus according to the first embodiment. This image forming apparatus is a tandem type electrophotographic color printer and has an intermediate transfer belt.

  The image forming apparatus includes an image forming unit 1Y that forms a yellow image, an image forming unit 1M that forms a magenta image, an image forming unit 1C that forms a cyan image, and an image that forms a black image. The image forming unit 1Bk includes four image forming units (image forming units). These four image forming units 1Y, 1M, 1C, and 1Bk are arranged in a row at a constant interval. In addition, a sheet feeding unit 17 is disposed below the sheet feeding unit 17. A recording medium transport path (paper feed guide) 18 is arranged vertically, and a fixing unit 16 is provided above the path.

  Each unit will be described in detail. In each of the image forming units 1Y, 1M, 1C, and 1Bk, drum-type electrophotographic photosensitive members (hereinafter referred to as photosensitive drums) 2a, 2b, 2c, and 2d are installed as image carriers. Around each photosensitive drum 2a, 2b, 2c, 2d, primary chargers 3a, 3b, 3c, 3d, developing devices 4a, 4b, 4c, 4d, transfer rollers 5a, 5b, 5c, 5d, and a drum cleaner device. 6a, 6b, 6c, 6d are respectively arranged. A laser exposure device 7 is installed below the primary chargers 3a, 3b, 3c and 3d and the developing devices 4a, 4b, 4c and 4d.

  Each photosensitive drum 2a, 2b, 2c, 2d is rotated and driven at a predetermined process speed in the direction of the arrow (clockwise direction) in the figure by a driving device (not shown). When the photosensitive drums 2a, 2b, 2c, and 2d are used without distinction, they are simply referred to as the photosensitive drum 2. The same applies to other codes.

  The primary chargers 3a, 3b, 3c, 3d uniformly charge the surface of each photosensitive drum 2a, 2b, 2c, 2d to a predetermined negative potential by a charging bias applied from a charging bias power source (not shown). .

  The laser exposure device 7 is disposed below the photosensitive drum, and includes a laser light emitting unit, a polygon lens, a reflection mirror, and the like that emit light corresponding to time-series electric digital pixel signals of given image information. The laser exposure device 7 exposes the photosensitive drums 2a, 2b, 2c, and 2d to the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d charged by the primary chargers 3a, 3b, 3c, and 3d. Then, an electrostatic latent image of each color corresponding to the image information is formed.

  Each of the developing devices 4a, 4b, 4c, and 4d stores yellow toner, cyan toner, magenta toner, and black toner, and each color is applied to each electrostatic latent image formed on each photosensitive drum 2a, 2b, 2c, and 2d. The toner is adhered and developed as a toner image (visualized image).

  The transfer rollers 5a, 5b, 5c, and 5d are arranged to be in contact with the photosensitive drums 2a, 2b, 2c, and 2d via the intermediate transfer belt 8 in the primary transfer portions 32a to 32d. The upper toner images are sequentially transferred onto the intermediate transfer belt 8 and superimposed.

  The drum cleaners 6a, 6b, 6c, and 6d are configured by a cleaning blade or the like, and scrape off residual transfer toner remaining on the photosensitive drum 2 during the primary transfer from each photosensitive drum 2 to clean the surface of the drum. .

  The intermediate transfer belt 8 is disposed on the upper surface side of each photosensitive drum 2 a, 2 b, 2 c, 2 d and is stretched between the secondary transfer counter roller 10 and the tension roller 11. The secondary transfer counter roller 10 is disposed in the secondary transfer portion 35 so as to be in contact with the secondary transfer roller 12 via the intermediate transfer belt 8.

  The image transferred to the intermediate transfer belt 8 is transferred onto the recording medium conveyed from the paper feeding unit 17 in the secondary transfer unit 35. A belt cleaning device (not shown) that removes and collects the transfer residual toner remaining on the surface of the intermediate transfer belt 8 is installed outside the intermediate transfer belt 8 and in the vicinity of the tension roller 11. By such a process, image formation with each toner is performed.

  The paper feed unit 17 has a cassette 17a for storing the recording medium P, a manual feed tray 20, and a pickup roller (not shown) for feeding the recording media P one by one from the cassette or from the manual feed tray. In addition, the paper feeding unit 17 supplies the recording medium P in accordance with the image forming timing of the paper feeding roller, the paper feeding guide 18, and the image forming unit that transports the recording medium P delivered from each pickup roller to the registration roller 19. A registration roller 19 is fed to the next transfer area.

  The fixing unit 16 includes a fixing film 16a having a heat source such as a ceramic substrate in which a heater 16c (see FIG. 2) is disposed, and a pressure roller 16b that is pressed against the substrate with the film interposed therebetween. Note that this pressure roller may include a heat source.

  Further, before and after the conveyance path of the fixing unit 16, a conveyance guide 34 that guides the recording medium P to the nip portion 31 of the roller pair, and an external discharge that guides the recording medium P discharged from the fixing unit 16 to the outside of the apparatus. A roller 21 is provided.

  The control unit includes a control board and a motor driver board (not shown) for controlling the operation of the mechanism in the unit.

  FIG. 2 is a block diagram showing the configuration of the control unit in the image forming apparatus. The control unit includes a controller unit 150 and an image processing unit 300. The controller unit 150 includes a CPU 201, a bus driver / address decoder circuit 202, a ROM 203, a RAM 204, an I / O interface 206, a PWM modulator 215, and an ACC / DEC module 220.

  The CPU 201 controls the entire image processing apparatus, and sequentially reads and executes a program from a read-only memory (ROM) 203 that stores a control procedure (control program) of the apparatus main body. The address bus and data bus of the CPU 201 are connected to each load via a bus driver / address decoder circuit 202.

  A random access memory (RAM) 204 is a main storage device used as storage of input data, a working storage area, and the like. Each load of the image forming apparatus is connected to the I / O interface (port) 206. For example, an operator performs key input and displays an operation panel 151 that displays the state of the apparatus using liquid crystal or LED, a stepping motor 207 that drives the paper feed unit 17 and the registration roller 19, a clutch 208, and a solenoid 209. Etc. are connected. In addition, paper detection sensors 210 and the like for detecting the conveyed paper are connected.

  Further, the developing device 4 is provided with a toner residual detection sensor 211 that detects the amount of toner in the developing device. The output signal is input to the I / O port 206. In addition, signals from switches 212 for detecting the home position of each load, the open / closed state of the door, and the like are also input to the I / O port 206.

  Further, a high voltage unit 213 is connected to the I / O port 206. The high voltage unit 213 outputs a high voltage to the primary charger 3 and the developing device 4 described above in accordance with an instruction from the CPU 201.

  The heater 16c is connected to the I / O port 206. The heater 16c is formed of a base material on which PTC elements are arranged. An AC voltage is supplied to the heater 16c by an on / off signal.

  The ACC / DEC module 220 receives the FG signal from the DC brushless motor 250 and outputs an ACC signal (acceleration signal) / DEC signal (deceleration signal) to the DC brushless motor 250. The DC brushless motor 250 drives the photosensitive drum 2, the developing device 4, the intermediate transfer belt 8, the fixing unit 16, and the like.

  The image processing unit 300 is equipped with a CPU and the like, and is connected to the CPU 201 by a serial signal or the like to perform communication, and exchanges output timing and the like to the engine unit. Further, when an image signal output from the connected personal computer 106 or the like is input, the image processing unit 300 performs image processing and outputs image data to the engine unit.

  The laser unit 117 outputs laser light according to the image data from the image processing unit 300. Laser light is applied to the photosensitive drum 2 to expose the photosensitive drum 2. Along with this exposure, in the non-image area, the beam detection sensor 214 (light receiving sensor) detects the light emission state of the laser light, and the output signal is input to the I / O port 206.

  Next, control of the DC brushless motor will be described. The motor for driving the fixing roller and the like of this embodiment is a three-phase DC brushless motor. FIG. 3 is a diagram showing a specific configuration of the motor control device. In this embodiment, the motor control device includes a controller unit 150 (control unit) and two DC brushless motors 250 and 450 (motor unit). Since DC brushless motors 250 and 450 (see FIG. 4) have the same configuration, DC brushless motor 450 is omitted in FIG. 3 for ease of explanation.

  The DC brushless motor 250 includes a motor control IC 301, a first driver circuit 351, a first motor (M1) 403, a second driver circuit 352, and a second motor (M2) 404. The motor control IC 301, the first driver circuit 351, and the second driver circuit 352 constitute a drive circuit 402 (see FIG. 4) described later. Since the first motor 403 and the second motor 404 have the same configuration, only the first motor 403 will be described. Similarly, since the first driver circuit 351 and the second driver circuit 352 have the same configuration, only the first driver circuit 351 will be described.

  The first motor 403 has three coils 315 to 317 of U, V, and W phases and a rotor (not shown). In addition, three Hall elements 318 to 320 are provided around the rotor shaft to detect the rotational position of the rotor, and these outputs are input to the motor control IC 301.

  One end of each of the three coils 315 to 317 is connected to the midpoint between the high-side FETs 302 to 304 and the low-side FETs 305 to 307, respectively, and the other ends are connected in common. Accordingly, the motor control IC 301 sequentially turns on / off the FETs 302 to 307 based on the rotational position information of the rotor detected by the Hall elements 318 to 320, and supplies current to the coils 315 to 317 so that the first motor 403 is turned on. Rotate.

  The current flowing through the first motor 403 is converted into a voltage by the current detection resistor 324. The motor control IC 301 performs PWM control when the high-side FETs 302 to 304 are turned on so that the detected current value is less than or equal to a predetermined current value.

  Further, fine multipolar magnetization is applied to the rotor end face, and a printed pattern (FG pattern) 325 on a rectangular wave is provided at a position facing it. When the rotor rotates, an AC voltage is induced at both ends of the FG pattern 325 and is detected by the motor control IC 301. Since the frequency of the detected AC voltage is proportional to the speed of the rotor, this AC voltage is shaped into a digital waveform in the motor control IC 301 and transmitted to the ACC / DEC module 220 as an FG signal representing the motor speed. .

  The ACC / DEC module 220 compares the frequency of the FG signal received from the first motor 403 with the target frequency of the FG signal calculated from the set target speed. Then, the ACC / DEC module 220 transmits an acceleration (ACC) signal to the motor control IC 301 when the actual speed obtained from the FG signal received with respect to the target speed is slow, and a deceleration (DEC) signal when the actual speed is fast. That is, the ACC / DEC module 220 counts the FG signal input from the motor with a counter, and compares the frequency of the FG signal obtained from the counted value with the frequency of the target rotation speed. Then, as a result of the comparison, the ACC / DEC module 220 outputs an acceleration signal or a deceleration signal having a pulse width corresponding to these differences. Therefore, the acceleration signal and the deceleration signal can be easily generated.

  The motor control IC 301 performs acceleration or deceleration according to the received signal, and controls the motor to rotate at a constant speed at the target speed.

  FIG. 4 is a block diagram showing a schematic configuration of the entire motor control device. As described above, in the DC brushless motor 250, two motors, that is, the first motor 403 and the second motor 404 are connected to the drive circuit 402 so that they can be driven. Similarly, in the DC brushless motor 450, two motors, that is, a third motor 457 and a fourth motor 458 are connected to the drive circuit 456 so as to be driven. In addition, each of the drive circuits 402 and 456 is provided on one motor board. Since the drive circuit is provided on one substrate, the motor unit can be reduced in size and cost.

  Further, a common signal line (detection signal line) 283 for transmitting an FG signal for each motor is connected between the ACC / DEC module 220 and the DC brushless motor 250 in the controller unit 150. Further, between the ACC / DEC module 220 and the DC brushless motor 250 in the controller unit 150, a common signal line (first control signal line) 281 that transmits an ACC signal and a common signal that transmits a DEC signal. A line (second control signal line) 282 is connected. Similarly, between the ACC / DEC module 220 and the DC brushless motor 450, three common signal lines 481, 482, and 483 for transmitting the ACC signal, the DEC signal, and the FG signal are connected.

  The drive circuit 402 receives the FG signal from the ACC / DEC module 220, calculates the speed from the FG signal, outputs the ACC signal / DEC signal based on the calculated speed, and performs speed control. These FG signal, ACC signal, and DEC signal are each transmitted through one signal line as described above. When the drive circuit 402 receives the ACC signal / DEC signal, the drive circuit 402 identifies whether the signal is the first motor 403 or the second motor 404, and the corresponding first motor 403 or second motor 404. Drive.

  FIG. 5 is a timing chart showing changes of each signal in the speed control of the DC brushless motor. Here, the FG signals of the first motor 403 and the second motor 404 are denoted as FG1 signal and FG2 signal, respectively. Further, the ACC signal / DEC signal of the first motor 403 and the second motor 404 are expressed as an ACC1 signal / DEC1 signal and an ACC2 signal / DEC2 signal, respectively.

  The CPU 201 receives an FG signal from the motor. The frequency of the FG signal changes in proportion to the speed. When the speed is high, the detection time of the FG signal is shortened and the frequency is increased. On the other hand, when the speed is low, the detection time of the FG signal becomes long and the frequency becomes low.

  The ACC / DEC module 220 has a target frequency of the FG signal corresponding to the target speed, and compares the frequency of the target speed with the FG signal from the motor. When the motor speed is slower than the target speed, the ACC / DEC module 220 outputs the ACC signal by the difference and accelerates it. On the contrary, when the motor speed is higher than the target speed, the ACC / DEC module 220 outputs the DEC signal by the difference and decelerates. That is, the pulse width of the ACC signal or the DEC signal increases as the difference in speed increases.

  Conventionally, three signal lines (FG signal, ACC signal, DEC signal) between the ACC / DEC module and the first motor, and three signal lines (FG signal) between the ACC / DEC module and the second motor. , ACC signal, DEC signal). That is, six signal lines are provided between the ACC / DEC module and the first and second motors.

  FIG. 6 is a timing chart showing speed control of the DC brushless motor performed in a time division manner. FIG. 7 is a timing chart showing changes of each signal in the speed control of the DC brushless motor performed in a time division manner.

  In the present embodiment, the FG signal, the ACC signal, and the DEC signal can be transmitted through one signal line by alternately transmitting the signal of the first motor 403 and the signal of the second motor 404 in a time division manner. .

  At the start of driving, the ACC / DEC module 220 performs calibration (adjustment) by simultaneously outputting L level signals of both the ACC signal and the DEC signal. This calibration is performed at regular intervals while the motor is driven. This calibration is performed to correct a deviation in the count of the FG frequency during driving of the motor and a deviation in the period between the FG1 signal and the FG2 signal. Therefore, the operation of the motor can be stabilized.

  When calibration is performed, output starts from the FG1 signal on the motor side. The motor control IC 301 alternately outputs the FG1 signal and the FG2 signal at regular time intervals. The periods of the FG1 signal and the FG2 signal are both 15 msec. This is because, if the period is too long, the interval between the ACC signal and the DEC signal output to the motor side becomes long, so that stable operation cannot be performed.

  The motor control IC 301 outputs the FG1 signal and the FG2 signal at different output voltages (voltage levels). The ACC / DEC module 220 identifies whether the signal is an FG1 signal or an FG2 signal based on the voltage of the FG signal. In this embodiment, the FG1 signal is a 5V pulse, whereas the FG2 signal is a 3V pulse. Thus, since the output voltage differs for each motor, the signal for each motor can be easily identified.

  Also in the ACC signal / DEC signal, the ACC signal / DEC signal of the first motor 403 and the second motor 404 is alternately output at regular intervals, like the FG signal. That is, the ACC / DEC module 220 alternately outputs the ACC1 signal and the ACC2 signal at regular intervals, and alternately outputs the DEC1 signal and the DEC2 signal at regular intervals. The ACC / DEC module 220 outputs the ACC1 signal and the ACC2 signal at different output voltages, and outputs the DEC1 signal and the DEC2 signal at different output voltages. The motor control IC 301 identifies whether the signal is the ACC1 signal, the ACC2 signal, the DEC1 signal, or the DEC2 signal based on the voltages of the ACC signal and the DEC signal. The ACC / DEC module 220 does not output the ACC signal / DEC signal while the FG signal is not input, and maintains the rotation state of the motor.

  As described above, according to the motor control apparatus of the first embodiment, when a plurality of motors are controlled by a single motor board, the number of signal lines for transmitting detection signals and control signals can be reduced. Therefore, it is possible to reduce the size and cost of the DC brushless motor provided with the motor substrate. In addition, by sharing the signal line through which the control signal is transmitted, the number of signal lines can be reduced and the pattern on the motor board can be reduced.

  In the present embodiment, the case where one drive circuit drives two motors has been described. However, the same control can be performed when three or more motors are driven. That is, the FG signal that is the detection signal, the ACC signal that is the first control signal, and the DEC signal that is the second control signal are each time-divisionally transmitted through one signal line. Thus, one detection signal line for a plurality of detection signals and one control signal line for a plurality of control signals can be used regardless of the number of motors. The same applies to the second embodiment described later.

  In this embodiment, the input times of the FG1 signal and the FG2 signal are set to be equal. However, when the motor drive speed is different, the input time may be changed according to the motor speed to have a difference. . Thereby, it can detect with high precision irrespective of a rotational speed.

[Second Embodiment]
The basic configuration of the image forming apparatus according to the second embodiment is the same as that of the first embodiment. In the first embodiment, in order to distinguish between the FG1 signal of the first motor and the FG2 signal of the second motor, which are FG signals, as shown in FIG. / DEC module 220 recognizes FG1 signal and FG2 signal.

  In the second embodiment, the motor control IC 301 changes the duty ratio of the pulse width of the FG1 signal and the FG2 signal, so that the ACC / DEC module 220 identifies the FG1 signal and the FG2 signal. FIG. 8 is a timing chart showing the change of the FG signal in the speed control of the DC brushless motor in the second embodiment. For example, the duty ratio of the FG1 signal is 50% while the duty ratio of the FG2 signal is 25%.

  The ACC / DEC module 220 recognizes which signal is the FG1 signal or the FG2 signal by performing digital / analog conversion (D / A conversion) of the input FG signal. The ACC / DEC module 220 detects the speed from this signal and outputs an ACC signal / DEC signal.

  As described above, according to the motor control device of the second embodiment, the output voltage of the FG signal can be single by changing the duty ratio of the pulse width in the FG1 signal and the FG signal 2, so that the power supply circuit can be simplified. Can be.

  The present invention is not limited to the configuration of the above-described embodiment, and any configuration can be used as long as the functions shown in the claims or the functions of the configuration of the present embodiment can be achieved. Is also applicable.

  For example, in the above embodiment, the detection signal line for the FG signal that is the detection signal, and the control signal lines (the first control signal line and the second control signal line) for the ACC signal and the DEC signal that are the control signals are common to each motor. The case is shown. The present invention can also be applied to the case where only one of the detection signal line and the control signal line is common to each motor.

  In the above embodiment, the case where the ACC signal and the DEC signal are transmitted as the control signals via the first control signal line and the second control signal line, respectively, but only one of them is transmitted as the control signal. Even in such a case, the present invention is applicable.

  In the above embodiment, the rotation of the rotor constituting the motor is detected. However, the following rotation may be detected. That is, a plurality of detected members that rotate in synchronization with a plurality of rotating bodies respectively driven by a plurality of motors are provided, and the rotation of the detected members is detected to detect the rotation of the motor. Also good. Thereby, the rotational speed of the rotating body can be controlled with high accuracy.

  In addition to the original printing apparatus, the image forming apparatus may of course be a facsimile machine having a printing function, a multifunction machine (MFP) having a printing function, a copying function, a scanner function, or the like.

  In the above-described embodiment, an intermediate transfer member is used as the image forming apparatus, toner images of respective colors are sequentially transferred onto the intermediate transfer member, and the toner image carried on the intermediate transfer member is used as a recording medium. An example of an image forming apparatus that performs batch transfer is illustrated. However, the present invention is not limited to this transfer method, and an image forming apparatus that uses a recording medium carrier and sequentially superimposes and transfers the toner images of each color carried on the recording medium carrier onto the recording medium. Good.

  In the above embodiment, the case where the printing method of the image forming apparatus is an electrophotographic method has been described as an example. However, the present invention is not limited to the electrophotographic method, but an ink jet method, a thermal transfer method, a heat sensitive method. It can be applied to various printing methods such as a method, an electrostatic method, and a discharge destruction method.

  Further, the sheet is not particularly limited, such as a paper medium, an OHP sheet, a cardboard sheet, and a tab sheet.

150 Controller 201 CPU
220 ACC / DEC module 250 DC brushless motor 301 Motor control IC
325 Print pattern (FG pattern)
402 Drive circuit 403 First motor 404 Second motor

Claims (9)

In a motor control device including a motor unit and a control unit,
The motor part is
Multiple motors,
A plurality of detection means for detecting the rotation of each of the plurality of motors and outputting a detection signal corresponding to the rotation speed;
For each of the plurality of motors, drive means for performing speed control according to a control signal for each motor,
The controller is
Based on a detection signal for each motor detected by the detection means, a control means for generating a control signal for each motor and outputting it to the drive means,
A detection signal for each motor is transmitted through a common detection signal line between the motor unit and the control unit, or a control signal for each motor is transmitted through a common control signal line. Motor control device. The control signal includes an acceleration signal for accelerating the motor and a deceleration signal for decelerating the motor,
2. The motor according to claim 1, wherein the acceleration signal for each motor is transmitted through a common first control signal line, and the deceleration signal for each motor is transmitted through a common second control signal line. Control device.   The control means includes a counting means for inputting the detection signals detected by the detecting means and counting the number thereof, and the acceleration signal or the deceleration having a pulse width corresponding to the count value counted by the counting means. The motor control device according to claim 2, wherein a signal is output to the driving unit. A plurality of rotating bodies respectively driven by the plurality of motors;
A plurality of detected members that rotate in synchronization with each of the plurality of rotating bodies,
The motor control device according to claim 1, wherein the plurality of detection units detect rotations of the plurality of motors by detecting rotations of the plurality of detected members.   The motor control apparatus according to claim 1, wherein the motor unit transmits the detection signal in a time division manner for each motor.   The motor control device according to claim 1, wherein the control unit transmits the control signal in a time division manner for each motor. The motor unit transmits the detection signal at a different output voltage for each motor,
The motor control apparatus according to claim 2, wherein the control unit identifies the motor based on a voltage of the detection signal. The control unit transmits the acceleration signal and the deceleration signal at different output voltages for each motor,
The motor control device according to claim 2, wherein the motor unit identifies the motor based on the acceleration signal and the deceleration signal. The motor unit transmits the detection signal with a pulse width having a different duty ratio for each motor,
The motor control device according to claim 1, wherein the control unit identifies the motor based on a duty ratio of the detection signal.