JP2005012932A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To materialize an image forming apparatus which performs the drive position control, the velocity control, etc. of two or more motors, which are performed with one motor control means, stably in a simple constitution. <P>SOLUTION: This image forming apparatus performs the speed control of photosensitive drums 1Y and 1M , using one CPU32, and a timer A35 and a timer B36 for every photosensitive drum. Since the generation timing of interruption signals from the timer A35 and the timer B36 to the CPU32 is set, being slid by half a control cycle, the interruption signals to perform the speed control of the photosensitive drums never compete with each other, and also generally uniform processing and action are performed by performing usual processing at intervals of speed control, and furthermore, this materializes stable speed control by the orderly repetition control for every photosensitive drum in speed control. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus having control means for driving and controlling a plurality of motors.
[0002]
[Prior art]
When an image is formed on recording paper using an image forming apparatus, a motor that is driven and controlled with high accuracy is used to drive the photosensitive drum, the intermediate transfer belt, and the like. For motor drive control, motor control means is provided for each motor, and the speed or drive position is individually controlled. (For example, refer to Patent Document 1).
[0003]
On the other hand, since a motor control means is provided for each motor, many motor control means such as a CPU or high-speed motor control means such as a DSP is required, which is a factor that increases costs. In order to solve this, for example, speed control of a plurality of motors is performed by one motor control means.
[0004]
[Patent Document 1]
JP-A-6-327278, (pages 3 to 4, FIGS. 1 to 3)
[0005]
[Problems to be solved by the invention]
However, according to the above prior art, the stability of the speed control of the motor is impaired. That is, when performing speed control of a plurality of motors by time-sharing control using one motor control means, control timing conflicts occur, and time-series processing is performed with priority. The output timing to becomes unstable.
[0006]
In particular, fluctuations in the speed of the drive motor in the image forming unit of the image forming apparatus cause distortion in the image formed on the recording paper and are not preferable.
[0007]
For these reasons, it is important how to realize an image forming apparatus that performs stable drive position control and speed control of a plurality of motors using a single motor control unit.
[0008]
The present invention has been made in order to solve the above-described problems caused by the prior art, and the drive position control and speed control of a plurality of motors performed using a single motor control means can be performed with a simple configuration and good stability. An object of the present invention is to provide an image forming apparatus.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve the object, an image forming apparatus according to a first aspect of the present invention is an image forming apparatus having a single control unit that controls a plurality of motor drive speeds and positions. The control means includes calculation means for calculating the speed and position control, and a control timing signal generation device for repeatedly performing the speed and position control. A timing signal is generated independently for each motor drive, and the timing signal is a timing at which the processing time of the calculation does not overlap.
[0010]
According to the first aspect of the present invention, the speed and position control of a plurality of motor drives is performed by one control means, the control means performs speed and position control calculations by the calculation means, and the control timing signal The speed and position are controlled repeatedly by the generator, and a timing signal is generated independently for each motor drive. This timing signal does not overlap the processing time of the operation. Thus, it is possible to perform control without impairing the stability of the drive control.
[0011]
According to a second aspect of the present invention, in the image forming apparatus according to the second aspect, when the number of a plurality of motors is N, the control unit repeatedly performs the speed and position control processing time for each motor drive. The time interval does not exceed 1 / (2N) times the time interval.
[0012]
According to the second aspect of the present invention, the drive control of all the motors can be performed without competing and maintaining stability without impairing the normal processing.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Exemplary embodiments of an image forming apparatus according to the present invention will be described below with reference to the accompanying drawings. Note that the present invention is not limited thereby.
(Embodiment 1)
First, the configuration of the image forming apparatus according to the present invention will be described with reference to FIGS. FIG. 2 is a functional block diagram illustrating a functional configuration of the image forming apparatus main body, and FIG. 3 is a diagram illustrating a mechanical configuration of an image forming unit, an input unit, and an output unit that configure the image forming apparatus.
[0014]
In FIG. 2, the image forming apparatus main body mainly includes an input panel 107, a CPU 100, a memory 300, a scanner 500, an image processing unit 600, an image forming unit 200, an input unit 400, and an output unit 700. More specifically, the image forming unit 200 includes a charger 10, an exposure unit 20, a developing unit 30, a fixing unit 50, and a conveyance unit 60. An input unit 400 and an output unit 700 include a conveyance unit 460, a discharge gate 720, and the like. including.
[0015]
The scanner 500 and the image processing unit 600 in FIG. 2 perform reading of an image of a document and image processing of the read image according to an instruction from the input panel 107. Then, the read image information is image-formed on a recording sheet, which is a transfer sheet, in the image forming unit 200. A document image reading instruction is input from the input panel 107. Details of the image forming unit 200 will be described with reference to FIG.
[0016]
In the image forming unit 200 of FIG. 3, 1Y to 1K are image carriers (photosensitive drums) on which latent images and toner images of respective colors are formed, and 2 and 3 are for driving the intermediate transfer member 4 at a predetermined speed. Intermediate transfer member drive roller, 10Y is a charger for charging for Y (yellow) image formation, 10M is a charger for charging for M (magenta) image formation, and 10C is for C (cyan). A charger 10 that performs charging for image formation, and 10K is a charger that performs charging for image formation of K (black). Each of the chargers 10Y to 10K in FIG. 3 constitutes the charger 10 in FIG. Further, an image forming agent for forming a latent image or a toner image, for example, a toner is attached to each of the carriers 1Y to 1K.
[0017]
3, 20Y is a writing unit that performs exposure for Y image formation, 20M is a writing unit that performs exposure for M image formation, and 20C is for C image formation. A writing unit for performing exposure and 20K is a writing unit for performing exposure for K image formation. Each of the writing units 20Y to 20K in FIG. 3 constitutes the exposure unit 20 in FIG. 2, and receives image information of each color from the image processing unit 600. Then, latent images of image information are formed on the image carriers 1Y to 1K.
[0018]
In the image forming unit 200 of FIG. 3, 30Y is a developing device that performs development for image formation (visualization of a latent image) on the Y image carrier 1Y, and 30M is an image on the M image carrier 1M. A developing unit that performs development for forming (visualization of a latent image), 30C is a developing unit that performs development for forming an image (making a latent image visible) on the C image carrier 1C, and 30K is It is a developing device that performs development for image formation (latent image visualization) on the K image carrier 1K. The developing units 30Y to 30K in FIG. 3 constitute the developing unit 30 in FIG. Image information formed on the image carriers 1Y to 1K by the writing units 20Y to 20K is converted from a latent image to a toner image by the developing devices 30Y to 30K, and is subjected to pressure bonding with the image carriers 1Y to 1K. Intermediate transfer is performed on the body 4. Thereafter, the toner image on the intermediate transfer body 4 is transferred onto the recording paper fed from the paper feed tray at a transfer nip portion sandwiched between the intermediate transfer body driving roller 3 and the transfer roller 62.
[0019]
3, 40Y is a cleaning unit that removes unnecessary toner after transfer on the Y image carrier 1Y, and 40M is a cleaning unit that removes unnecessary toner after transfer on the M image carrier 1M. 40C is a cleaning unit for removing unnecessary toner after transfer on the C image carrier 1C, and 40K is a cleaning unit for removing unnecessary toner after transfer on the K image carrier 1K. 40 ^｀ Is a cleaning unit for removing unnecessary toner after transfer on the intermediate transfer body 4. In these cleaning units, unnecessary toner on the image carriers 1Y to 1K and the intermediate transfer member 4 is removed.
[0020]
Reference numeral 70 denotes a separation unit which is made up of a charge eliminating needle and discharges the recording paper from the intermediate transfer member 4. A fixing unit 50 fixes the toner image transferred onto the recording paper by heat and pressure. The transfer roller 62 is a transport unit that transports the recording paper, and transports the recording paper at a predetermined speed at a transfer position with the intermediate transfer body 4. The transfer roller 62 constitutes the conveying unit 60 in FIG.
[0021]
In the input unit 400 of FIG. 3, the recording paper fed from the paper feed tray 101 is advanced to the position of the registration rollers 430 and 431 by the guide plate 440. Thereafter, the recording paper is conveyed to a transfer nip portion sandwiched between the intermediate transfer body driving roller 3 and the transfer roller 62, and the toner image on the intermediate transfer body 4 is transferred onto the recording paper fed from the paper feed tray. . The recording sheet is fixed by the fixing unit 50, then carried into the output unit 700, and discharged to one of the discharge trays 108 and 109 selected by the discharge gate 720.
[0022]
Here, the photosensitive drums 1Y to 1K, the intermediate transfer body driving rollers 2 and 3 and the like when the image is formed on the recording paper are driven by a motor whose speed or driving position is controlled and included in the conveying means 60. The rotational speed of the body drums 1Y to 1K, the moving speed of the intermediate transfer body 4 or the conveying speed of the recording paper, and the rotation and moving position thereof are also controlled with high accuracy, and image formation with less distortion is performed.
[0023]
FIG. 1 is a block diagram of a motor control unit 31, motor drive circuits 81 and 82, and speed information generation circuits 83 and 84 that constitute a control unit included in the transport unit 60 that controls the speed of the photosensitive drums 1Y and 1M. Show. Here, the photosensitive drums 1Y and 1M are fixed to a drive shaft, and the drive shaft is supported by a bearing so as to be rotatable. The drive shaft is driven by a motor through a reduction gear.
Although FIG. 1 illustrates the case where the two control systems of the photoconductive drums 1Y and 1M are illustrated, four photoconductive drums 1Y to 1K, and a drive system using other motors may be included. .
[0024]
In addition, an encoder is attached to the drive shaft, and the rotational speed of the drive shaft and consequently the photosensitive drum is measured. This encoder consists of a disk with slits arranged on the circumference at equal intervals. The encoder detects the speed of the slit with a speed detector consisting of a light source and a light detector that exists across the slit, and further rotates the disk. Calculate the speed.
[0025]
The speed information generation circuits 83 and 84 calculate the rotation speed of the encoder and, in turn, the rotation speed of the photosensitive drums 1Y and 1Z from the speed information of the slit detected by the speed detector, and transmit it to the motor control unit 31 as control information. .
[0026]
The motor drive circuits 81 and 82 rotate the photosensitive drums 1Y and 1Z at a predetermined rotation speed. Here, the motor drive circuits 81 and 82 maintain and adjust the rotational speed of the motor with high accuracy based on the control information from the motor control unit 31. Thereby, the rotation unevenness of the photosensitive drums 1Y and 1Z is reduced.
[0027]
The motor control unit 31 serving as a control unit controls the motor drive circuits 81 and 82 based on the rotational speed information of the drive shaft from the speed information generation circuits 83 and 84 and the drive start or stop information from the CPU 100, and the photosensitive member. The rotation of the drums 1Y and 1Z is controlled with high accuracy. Here, the control based on the rotational speed information from the speed information generating circuits 83 and 84 is repeatedly performed while the photosensitive drums 1Y and 1M are driven by the motor, and the target rotational speed is maintained with high accuracy. Is done.
[0028]
The motor control unit 31 serving as a control unit includes a CPU 32 serving as a calculation unit, a memory 33, a timer A35 serving as a control timing signal generator, and a timer B36. Here, the memory 33 stores a program of a control process A37 for controlling the speed of the photosensitive drum 1Y and a control process B38 for controlling the photosensitive drum 1M. The control process A37 and the control process B38 compare the actually measured rotational speed information from the speed information generation circuits 83 and 84 with the target rotational speed information of the motor, and use, for example, PID control from the deviation. Thus, the optimum control amount for the motor drive circuit 81 or 82 is determined.
[0029]
FIG. 1 illustrates the case where the two control systems of the photosensitive drums 1Y and 1M are illustrated. However, even when two or more control systems are included, the control is performed using the single CPU 32 in the same manner. . In this case, control processes corresponding to the number of control systems are stored in the memory 33, and timers corresponding to the number of control systems are arranged in the motor control unit 31.
[0030]
A timer A35 and a timer B36 that form a control timing signal generator generate an interrupt signal to the CPU 32. When the interrupt signal is from the timer A35, the CPU 32 executes the program of the control process A37, determines the control amount to the motor drive circuit 81, and outputs it. If it is from the timer B36, the program of the control process B38 is executed to determine and output the control amount to the motor drive circuit 82.
[0031]
The memory 33 also stores a setting process 34 that is a program serving as setting means. The setting process 34 performs initial settings such as setting the control cycle of the motor drive circuits 81 and 82 and the timing for generating an interrupt signal for the timer A35 and the timer B36. Here, a functional block diagram of the timer A35 and the timer B36 is shown in FIG.
[0032]
The timer A35 and the timer B36 include period counters 43 and 53, period registers 44 and 54, interrupt registers 45 and 55, comparison circuits 46 and 56, and the like. In the timer A35, the period counter 43 counts the input from the clock and counts up. The period register 44 sets an interval of timing for generating an interrupt signal by the setting process 34. The interrupt register 45 is set by the setting process 34 to generate an interrupt signal.
[0033]
The comparison circuit 46 compares values between the period counter 43 and the period register 44 or the interrupt register 45, and generates a trigger signal if they match. Here, when the values of the period register 44 and the period counter 43 match, the period counter 43 is reset by the generated trigger signal, and the count-up is repeated from the zero value. When the values of the interrupt register 45 and the cycle counter 43 match, the CPU 32 is interrupted by the generated trigger signal, and the control process A is executed. Note that the same applies to the timer B36, and detailed description thereof will be omitted, but the control process B is executed by an interrupt signal to the CPU 32.
[0034]
Next, the speed control operation of the motor control unit 31 will be described using the flowchart of FIG. The flowchart in FIG. 5 is an example in the case where the number of control systems N = 2, which is the control system shown in FIG. In the case of N> 2, description will be made at each step of the flowchart as appropriate.
[0035]
First, the CPU 32 receives a speed control start command for the photosensitive drums 1Y and 1M from the CPU 100, and starts speed control. The CPU 32 reads the setting process 34 of the memory 33 as setting means and starts execution. The setting process 34 reads the control cycle Ta for controlling the rotation speed of the motor into the cycle registers 44 and 54 of the timer A35 and the timer B36 (step S501). Here, the control cycle is set to a cycle that can sufficiently detect the rotation unevenness generated in the photosensitive drums 1Y and 1M based on the sampling theorem.
[0036]
Thereafter, the CPU 32 reads the value T2 of the interrupt register 55 of the timer B36 based on the setting process 34 (step S502). Thus, this value T2 is used as a reference for determining the value of the interrupt register 45 of the timer A35.
Then, a value shifted by half the control period Ta from the value T2 of the interrupt register 55 of the timer B36 is calculated and substituted for the value Tb of the interrupt register 45 of the timer A35 (step S503).
[0037]
Tb = T2 + Ta / 2
If there are two or more control systems, the number of control systems is N, and the interrupt register number of the timer corresponding to each control system is n (1 ≦ n ≦ N). For the value T2 of number 1,
Tb = T2 + (Ta / N) * (n-1)
Thus, the value of the nth interrupt register is determined.
[0038]
Thereafter, based on the setting process 34, the CPU 32 determines whether or not the value Tb of the interrupt register 45 exceeds the repetition control period Ta (step S504). The value of the period counter 43 is repeatedly counted from zero with Ta as the maximum value. Therefore, if Tb> Ta (Yes in step S504), the value T1 written to the interrupt register is set to
T1 = Tb-Ta
Thus, the interrupt generation timing of the timer A35 and the timer B36 can be shifted by Ta / 2. If Tb> Ta is not satisfied (No at step S504), the value T1 written to the interrupt register is set to
T1 = Tb
Thus, the interrupt generation timings of the timer A35 and the timer B36 can be shifted by Ta / 2. Even when the number of control systems is N> 2 or more, if Tb exceeds Ta, the value of Tb−Ta is used as the interrupt register value of the corresponding timer.
[0039]
Thereafter, the CPU 32 writes the value T1 into the interrupt register 45 of the timer A35 based on the setting process 34 (step S507). Then, the period counters 43 and 53 of the timer A35 and the timer B36 are reset to zero values, and counting is started (step S508).
[0040]
Thereafter, the CPU 32 performs normal processing (step S509). This normal processing includes various timer interruptions other than control of the photosensitive drum 1Y or 1M, or interruption processing such as communication processing. Further, the CPU 32 always checks the interrupt signal from the timer A35 or the timer B36 during the normal processing (step S511).
[0041]
Here, when the cycle counters 43 and 53 reach a count value that matches the value of the interrupt registers 45 and 55, an interrupt signal is generated by the comparison circuits 46 and 56. In this case, the CPU 32 detects this interrupt signal (Yes at Step S511), saves the routine for normal processing at Step S509, and performs control processing (Step S512). In this control process, the control process A37 or B38 of the memory 33 is selected in response to an interrupt from the timer A35 or the timer B36 and processed by the CPU 32. Then, a control value is determined based on the speed information from the speed information generation circuit 83 or 84 and is output to the motor drive circuit 81 or 82.
[0042]
Thereafter, the CPU 32 returns to the normal process and continues reading the saved normal process again (step S509 ′). If there is no interrupt (No at step S511), the control process at step S512 is not performed, and the normal process at step S509 is continued. If the interrupt occurs again during the normal process, the processes in steps S511 and S512 are repeated.
[0043]
Thereafter, the CPU 32 determines whether or not there is a control stop command from the CPU 100 (step S513). If there is no control stop command (No at step S513), the CPU 32 proceeds to step S509 and performs normal processing and further interrupts. If there is, the control process is repeated. If there is a control stop command (Yes at step S513), this control process is terminated.
[0044]
In FIG. 6, the processes in steps S509 to S512 are shown for each control system in the vertical direction with the horizontal axis as a common time axis. In addition, the length of the arrow in the figure represents the processing time of the control system. Here, since the interrupt register values of the timer A35 and the timer B36 are different by Ta / 2, the interrupt generation timing is different by Ta / 2. Therefore, the control process for controlling the rotation speeds of the photosensitive drums 1Y and 1M. A and the control process B are repeatedly executed alternately with a time difference of Ta / 2. Further, the normal process other than the speed control of the photosensitive drum is executed during the idle time when the process of the control process A or the control process B is not performed as exemplified by the general-purpose timer or communication in FIG.
[0045]
Further, each processing time of the control process A and the control process B indicated by the length of the arrow in FIG. 6 is set within Ta / 4. Thus, half of the control cycle Ta is allocated to the control process A or control process B, and the other half is allocated to the normal process. Operation is performed. When the number of control systems is N, it is preferable to set the control processing time of each control system within 1 / (2N) of the control cycle. As a result, even when the number of control systems is N, as in the case of two control systems, the processing time for normal processing is ensured and uniform processing and operation are performed as a whole.
[0046]
As described above, in the first embodiment, the speed control of the photosensitive drums 1Y and 1M is performed using one CPU and the timer A35 and the timer B36 for each photosensitive drum. Since the generation timing of the interrupt signal from B36 is set to be shifted by a half of the control cycle Ta, the interrupt signal for controlling the speed of the photosensitive drum does not compete, and regular repeated control is performed for each photosensitive drum. Stable speed control can be performed.
[0047]
In the first embodiment, the interrupt registers of the timers A35 and B36 are set to values that differ by half of the control cycle Ta, but the values of the cycle counters 43 and 53 differ from those that differ by half of the control cycle Ta. You can also In this case, the value of the interrupt register can be set to the same value in the timers A35 and B36, and the timing of the generated interrupt signal can be different by Ta / 2. The same can be done when two or more control systems are provided.
[0048]
In the first embodiment, the motor control unit 31 is configured by the CPU 32, the memory 33, the timer A35, the timer B36, and the like. It can also be configured.
Thereby, the motor control unit 31 can be made small and highly reliable, and at the same time, the speed can be further increased and high-precision control can be performed.
(Embodiment 2)
By the way, in Embodiment 1 described above, the speed control during the rotation of the photosensitive drums 1Y and 1M is performed stably by the motor control unit 31, but when the photosensitive drums 1Y and 1M are stopped, etc. The drive position control can also be performed by the motor control unit 31. Therefore, in the present embodiment, a case where drive position control is performed using the motor control unit 31 will be described.
[0049]
FIG. 7 is a block diagram of the motor control unit 31, the motor drive circuits 81 and 82, and the position information generation circuits 85 and 86 that control the drive positions of the photosensitive drums 1 </ b> Y and 1 </ b> M. Indicates. The motor control unit 31 includes a control process C27, a control process D28, a timer C25 and a timer D26 that form a control timing signal generator.
[0050]
Here, the position information generating circuits 85 and 86 correspond to the speed information generating circuits 83 and 84 of FIG. 1, and the control processing C27, control processing D28, timer C25 and timer D26 of the motor control unit 31 are shown in FIG. 1 corresponds to the first control process A37, control process B38, timer A35 and timer A36, and the others are the same as in FIG.
[0051]
The position information generating circuits 85 and 86 detect the relative rotational positions of the encoders attached to the drive shafts of the photosensitive drums 1Y and 1M using a position detector. Here, the encoder and the position detector are the same as the encoder and the speed detector used in the first embodiment.
[0052]
The control process C27 and the control process D28 compare with the target rotation position of the motor based on the rotation position information from the position information generation circuits 85 and 86, and based on the deviation, make a rotation position with no further error. The control amount is output to the motor drive circuit 81 or 82.
[0053]
The timer C25 and the timer D26 generate an interrupt signal to the CPU 32 as in the first embodiment. When the interrupt signal is from the timer C25, the CPU 32 executes the program of the control process C27, determines the control amount to the motor drive circuit 81, and outputs it. If it is from the timer C26, the control processing D28 program is executed to determine and output the control amount to the motor drive circuit 82.
[0054]
The operation of the drive position control of the motor control unit 31 is the same as the speed control of the motor control unit 31 illustrated in the flowchart of FIG. However, the control cycle Ta for controlling the rotational speed of the motor used in step S501 of FIG. 5 is used instead of the control cycle Ta for controlling the rotational position of the motor.
[0055]
As described above, in the second embodiment, the motor control unit 31 controls the motor drive circuits 81 and 82 based on the rotational position information of the photosensitive drums 1Y and 1M from the position information generation circuits 85 and 86. Therefore, the photosensitive drums 1Y and 1M can be adjusted to an accurate rotational position when the photosensitive drums 1Y and 1M are stopped with a stable control cycle.
[0056]
In the second embodiment, the photosensitive drums 1Y and 1M are targeted for control, but two or more other drive systems constituting the recording paper conveying means 60 can also be targeted.
[0057]
In the first and second embodiments, the example in which the speed control and the drive position control are performed separately has been described. However, these controls can be performed simultaneously.
[0058]
【The invention's effect】
As described above, according to the first aspect of the present invention, a plurality of motor drive speeds and positions are controlled by a single control means, and the control means performs speed and position control calculations by the calculation means. The control timing signal generator repeatedly performs speed and position control, and further generates a timing signal independently for each motor drive, so that the timing signal does not overlap the processing time of the calculation, so it is inexpensive. Moreover, it is possible to perform control without impairing the stability of drive control for each motor.
[0059]
According to the second aspect of the present invention, the drive control of all the motors can be performed without competing and maintaining stability without impairing the normal processing.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a portion related to a motor control unit when speed control of a photosensitive drum is performed.
FIG. 2 is a functional block diagram illustrating a functional overall configuration of the image forming apparatus.
FIG. 3 is a block diagram illustrating an overall configuration of hardware of the image forming apparatus.
FIG. 4 is a block diagram illustrating a configuration of a timer of a motor control unit.
FIG. 5 is a flowchart showing the operation of the CPU of the motor control unit.
FIG. 6 is a time chart showing timing at which a CPU performs control processing.
FIG. 7 is a diagram illustrating a configuration of a portion related to a motor control unit when driving position control of the photosensitive drum is performed.
[Explanation of symbols]
1Y, 1M, 1C, 1K Image carrier (photosensitive drum)
2, 3 Intermediate transfer member drive roller
4 Intermediate transfer member
10Y, 10M, 10C, 10K charger
20Y, 20M, 20C, 20K writing unit
20 Exposure means
30Y, 30M, 30C, 30K Developer
31 Motor controller
33, 300 memory
34 Setting process
43,53 period counter
44, 54 period register
45, 55 Interrupt register
46,56 comparison circuit
50 Fixing unit
60 Conveying means
62 Transfer roller
81, 82 Motor drive circuit
83, 84 Speed information generation circuit
85,86 Position information generation circuit
101 Paper tray
107 Input panel
108 Output tray
200 Image forming unit
400 input section
430 Registration Roller
440 Guide plate
460 Conveying means
500 scanner
600 Image processing unit
700 Output unit
720 Exit gate
35, 36 timers

Claims (2)

An image forming apparatus having one control means for performing speed control and position control of a plurality of motors,
The control means includes calculation means for calculating the speed and position control, and a control timing signal generator for repeatedly performing the speed and position control,
The control timing signal generator generates a timing signal independently for each motor drive,
The image forming apparatus according to claim 1, wherein the timing signal is a timing at which the processing time of the calculation does not overlap. When the number of a plurality of motors is N, the control means sets the processing time for the speed and position control for each motor drive to a time that does not exceed 1 / (2N) times the repetition time interval. The image forming apparatus according to claim 1.

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