JP2021027618A - Control device, control method, and program - Google Patents

Abstract

To appropriately control a driven shaft.SOLUTION: A control device according to an aspect of the disclosed technology comprises a drive control unit that, based on a detection signal from an angle detection unit provided on a motor, of a plurality of motors driving a driven shaft through a belt member, which is on the downstream side of the driven shaft in the direction of travel of the belt member, controls the respective drives of the plurality of motors.SELECTED DRAWING: Figure 2

Description

The present invention relates to control devices, control methods and programs.

Conventionally, there is known a control device that uses a plurality of motors and controls the drive of a single driven shaft via a belt member.

Further, a technique for performing highly accurate drive control of a rotating body such as a belt member based on a detection signal of a position detection unit provided on the motor shaft and the belt member is disclosed (see, for example, Patent Document 1).

However, in the conventional technique, there are cases where the driven shaft cannot be appropriately controlled.

The disclosed technique makes it an object to appropriately control the driven shaft.

The control device according to one aspect of the disclosed technique is provided in a motor located downstream of the driven shaft in the traveling direction of the belt member among a plurality of motors for driving the driven shaft via the belt member. A drive control unit that controls each drive of the plurality of motors based on a detection signal by the angle detection unit is provided.

According to the disclosed technique, the driven shaft can be appropriately controlled.

It is a figure which shows the configuration example of a plurality of motors and a driven shaft which concerns on 1st Embodiment. It is a block diagram which shows the functional structure example of the control device which concerns on 1st Embodiment. It is a flowchart which shows the processing example by the control apparatus which concerns on 1st Embodiment. It is a figure which shows the structural example of the plurality of motors and the driven shaft which concerns on 2nd Embodiment.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings. In each drawing, the same components may be designated by the same reference numerals and duplicate description may be omitted.

[First Embodiment]
First, a configuration for rotationally driving one driven shaft 4 via a cogged belt 3 using two motors, a first motor 1 and a second motor 2, will be described with reference to FIG. FIG. 1 is a diagram showing an example of the configuration of the first motor 1, the second motor 2, the cogged belt (toothed belt) 3, and the driven shaft 4 according to the first embodiment.

The driven shaft 4 is a mechanical element that is connected to the rotating shaft of the rotating body and rotates the rotating body by rotating the driven shaft 4 around the axis. Examples of the rotating body include various rollers such as a paper feed roller, a transfer roller, a secondary transfer roller, and a fixing roller used in an image forming apparatus.

The cogged belt 3 is wound around a pulley 12 attached to the motor shaft 11 of the first motor 1, a pulley 22 attached to the motor shaft 21 of the second motor 2, and a pulley 41 attached to the driven shaft 4. Has been done. The cogged belt 3 as an example of the belt member travels with the rotation of the first motor 1 and the second motor 2, and transmits torque to the driven shaft 4 via the pulley 41.

The first encoder 13 provided on the motor shaft 11 of the first motor 1 outputs the first encoded signal enc1 which is a pulse signal in response to the rotation of the first motor 1. Further, the second encoder 23 provided on the motor shaft 21 of the second motor 2 outputs a second encode signal enc2 which is a pulse signal in response to the rotation of the second motor 2. Here, each of the first encoder 13 and the second encoder 23 is an example of the “angle detection unit”.

The control device 110, which will be described later, controls the first motor 1 based on the first encoded signal enc1 and controls the second motor 2 based on the second encoded signal enc2 to rotate the driven shaft 4 in the rotation direction. The position, rotation speed, etc. can be controlled. Here, the first motor 1 and the second motor 2 rotate in either the CW (clockwise) direction or the CCW (counterclockwise) direction, and the first motor 1 and the second motor 2 rotate in the same direction. In the example of FIG. 1, the first motor 1 and the second motor 2 rotate in the CCW direction, and the driven shaft 4 is rotationally driven in the CCW direction via the cogged belt 3.

A DC (Direct Current) brushless motor, a stepping motor, or the like can be used for the first motor 1 and the second motor 2.

The driven pulley 5 provided between the first motor 1 and the second motor 2 is for suppressing loosening of the cogged belt 3, and applies tension to the cogged belt 3 while rotating as the cogged belt 3 travels. ..

In the example of FIG. 1, the first motor 1 rotates in the direction of the arrow 10 of the alternate long and short dash line, the second motor 2 rotates in the direction of the arrow 20 of the alternate long and short dash line, and the cogged belt 3 travels in the direction of the arrow 30 of the solid line. doing. The driven shaft 4 is rotated in the direction of the broken line arrow 40 due to the torque accompanying the traveling of the cogged belt 3. Each direction of arrows 10, 20, 30 and 40 corresponds to the CCW direction.

Here, in the rotating state of FIG. 1, the portion wound between the first motor 1 and the driven shaft 4 in the cogged belt 3 due to the load applied to the drive system 100, the inertia of the driven shaft 4, and the like. In some cases, the tension increases and the cogged belt 3 becomes taut. On the other hand, the tension of the portion of the cogged belt 3 wound between the second motor 2 and the driven shaft 4 may decrease, and the cogged belt 3 may become loose.

The slack of the cogged belt 3 causes play between the pulley 22 of the second motor 2 and the cogged belt 3, so that the rotation angle based on the detection signal by the second encoder 23 and the actual rotation angle of the driven shaft 4 There may be a gap between them. Due to such a deviation, a follow-up delay in the feedback control of the driven shaft 4 using the detection signal by the second encoder 23 and phenomena such as resonance and semi-resonance in the running of the cogged belt 3 are generated, and the driven shaft 4 is appropriately adjusted. May be out of control.

Therefore, in the present embodiment, of the first motor 1 and the second motor 2 that drive the driven shaft 4 via the cogged belt 3, the motor is provided on the downstream side of the driven shaft 4 in the traveling direction of the cogged belt 3. The drive of each of the first motor 1 and the second motor 2 is controlled based on the detection signal by the encoder.

In the example of FIG. 1, the first motor 1 and the second motor 2 are based on the detection signals provided by the first encoder 13 provided on the first motor 1 on the downstream side of the driven shaft 4 in the CCW direction in which the cogged belt 3 travels. Each drive is controlled.

By doing so, the cogged belt 3 can be controlled without using the detection signal by the encoder provided in the motor on the loose side, so that the follow-up delay in the feedback control of the driven shaft 4 and the resonance in the running of the cogged belt 3 occur. It is possible to prevent phenomena such as semi-resonance.

Hereinafter, the present embodiment will be described by taking a drive system 100 including the control device 110 as an example.

<Functional configuration of control device 110>
First, the functional configuration of the control device 110 will be described. FIG. 2 is a block diagram illustrating an example of the functional configuration of the control device 110. As shown in FIG. 2, the control device 110 includes a belt traveling direction detection unit 111, an encoder selection unit 112, a drive control unit 113, and PWM generation units 114 and 115.

All of these functions are realized by electronic circuits. However, the present invention is not limited to this, and some or all of the functions shown above may be realized by the CPU (Central Processing Unit) executing predetermined software. Further, it may be realized by a combination of a plurality of circuits or a plurality of software.

The belt traveling direction detecting unit 111 is an example of the detecting unit, and detects the traveling direction of the cogged belt 3 based on the position target value xtgt and the speed target value vtgt input from the host controller of the drive system 100.

For example, if the sign of the position target value xtgt or the speed target value vtgt is positive, it is detected that the traveling direction of the cogged belt 3 is the CCW direction, and if the above sign is negative, the traveling direction of the cogged belt 3 is CW. Detects the direction. Then, the detection result is output to the encoder selection unit 112.

However, the above-mentioned detection method is an example, and if the sign of the position target value xtgt or the speed target value vtgt is negative depending on the arrangement of the first motor 1 and the second motor 2, the traveling direction of the cogged belt 3 is CW. If it is detected that the direction is positive and the above reference numeral is positive, it may be detected that the traveling direction of the cogged belt 3 is the CW direction.

Further, the belt traveling direction detection unit 111 may detect the traveling direction of the cogged belt 3 by inputting information indicating the traveling direction of the cogged belt 3 from the host controller of the drive system 100. Further, the belt traveling direction detecting unit 111 may detect the traveling direction of the cogged belt 3 based on the detection signal by either the first encoder 13 or the second encoder 23. Further, in addition to the first encoder 13 and the second encoder 23, a sensor for detecting the position or speed of the cogged belt 3 in the traveling direction is provided, and the belt traveling direction detecting unit 111 travels the cogged belt 3 based on the detection signal by the sensor. The direction may be detected.

The encoder selection unit 112 is an example of a selection unit, in which the first encoder 13 inputs the first encode signal ench1 and the second encoder 23 inputs the second encode signal enc2. Then, in response to the detection result of the traveling direction of the cogged belt 3 by the belt traveling direction detecting unit 111, a motor located downstream of the driven shaft 4 in the traveling direction of the cogged belt 3 is selected, and an encoder provided in the selected motor is selected. Is output to the drive control unit 113.

For example, in the example of FIG. 1, since the cogged belt 3 travels in the CCW direction, the encoder selection unit 112 drives and controls the first encoded signal enc1 of the first encoder 13 on the downstream side of the driven shaft 4 in the CCW direction. Output to 113.

On the other hand, when the cogged belt 3 travels in the CW direction, the encoder selection unit 112 outputs the second encode signal enc2 of the second encoder 23 located on the downstream side of the driven shaft 4 in the CW direction to the drive control unit 113.

The drive control unit 113 is an example of the drive control unit, and inputs the position target value xtgt and the speed target value vtgt from the host controller of the drive system 100. Further, the drive control unit 113 inputs either one of the first encoded signal enc1 and the second encoded signal enc2 from the encoder selection unit 112. Then, based on the input encoded signal, the current position value xdet and the current velocity value vdet of the driven shaft 4 are acquired.

After that, the drive control unit 113 performs PID (Proportional Integral Differential) control based on the position target value xtgt and the speed target value vtgt, and the position current value xdet and the speed current value vdet. Then, the PWM generation unit uses the first drive command value of the first motor 1 generated to match the position of the driven shaft 4 with the position target value xtgt and the speed of the driven shaft 4 with the speed target value vtgt. Output to 114. The drive control unit 113 outputs the second drive command value of the second motor 2 similarly generated to the PWM generation unit 115.

The PWM generation unit 114 generates a PWM signal having a duty ratio in response to the first drive command value input from the drive control unit 113, and supplies the PWM signal to the driver 103.

The PWM generation unit 115 generates a PWM signal having a duty ratio in response to the second drive command value input from the drive control unit 113, and supplies the PWM signal to the driver 104.

The driver 103 operates according to the PWM signal supplied from the PWM generation unit 114 to apply a drive voltage to each phase of U, V, and W in the first motor 1. As a result, the first motor 1 rotates. The driver 103 may be provided inside the first motor 1 or may be provided outside the first motor 1.

The driver 104 operates according to the PWM signal supplied from the PWM generation unit 115 to apply a drive voltage to each phase of U, V, and W in the second motor 2. As a result, the second motor 2 rotates. The driver 104 may be provided inside the second motor 2 or may be provided outside the second motor 2.

<Control operation by control device 110>
Next, the control operation by the control device 110 will be described with reference to FIG. FIG. 3 is a flowchart showing an example of a control operation by the control device 110. In the following, a case where control is performed using the position target value xtgt and the position current value xdet will be described as an example.

First, in step S31, the belt traveling direction detecting unit 111 detects the traveling direction of the cogged belt 3 based on the position target value xtgt input from the host controller of the drive system 100, and outputs the detection result to the encoder selection unit 112.

Subsequently, in step S32, the encoder selection unit 112 inputs the first encoded signal enc1 from the first encoder 13 and also inputs the second encoded signal enc2 from the second encoder 23. Then, in response to the detection result of the traveling direction of the cogged belt 3 by the belt traveling direction detecting unit 111, it is determined whether or not the rotation direction of the cogged belt 3 is the CCW direction.

If it is determined in step S32 that the direction is in the CCW direction (step S32, Yes), in step S33, the encoder selection unit 112 outputs the first encoded signal enc1 to the drive control unit 113.

On the other hand, if it is determined in step S32 that the direction is not in the CCW direction (step S32, No), in step S34, the encoder selection unit 112 outputs the second encoded signal enc2 to the drive control unit 113.

Subsequently, in step S35, the drive control unit 113 acquires the position current value xdet of the driven shaft 4 based on either the first encoded signal enc1 or the second encoded signal enc2 input from the encoder selection unit 112. ..

After that, the drive control unit 113 performs PID control based on the position target value xtgt input from the host controller of the drive system 100 and the position current value xdet, and generates the first drive command value of the first motor 1. Output to the PWM generation unit 114. Similarly, the drive control unit 113 generates the second drive command value of the second motor 2 and outputs it to the PWM generation unit 115.

Subsequently, in step S36, the PWM generation unit 114 generates a PWM signal having a duty ratio in response to the first drive command value. Further, the PWM generation unit 115 generates a PWM signal having a duty ratio in response to the second drive command value.

Subsequently, in step S37, the PWM generation unit 114 supplies the generated PWM signal to the driver 103. Further, the PWM generation unit 115 supplies the generated PWM signal to the driver 104.

Subsequently, in step S38, the drive control unit 113 determines whether or not to end the control.

If it is determined in step S38 that the control is terminated (step S38, Yes), the control operation is terminated. On the other hand, if it is determined that the control is not terminated (steps S38, No), the process returns to step S31, and the control operations of steps S31 to S38 are repeated again.

In this way, the control device 110 can control the rotational drive of the driven shaft 4 via the cogged belt 3 by using the first motor 1 and the second motor 2.

<Operation and effect of control device 110>
Conventionally, there is known a control device that uses a plurality of motors and controls the drive of a single driven shaft via a belt member. Further, a technique for highly accurate drive control of a rotating body such as a belt member is disclosed based on a detection signal of a position detection unit provided on the motor shaft and the belt member.

However, the tension may decrease at the portion of the belt member wound between the predetermined motor and the driven shaft among the plurality of motors, and the belt member may be in a loosened state. Due to the looseness of the belt member, play occurs between the pulley of the predetermined motor and the belt member, so that the rotation angle based on the detection signal by the encoder provided in the predetermined motor and the actual driven shaft There may be a deviation from the rotation angle of.

Then, due to such a deviation, a follow-up delay in the feedback control of the driven shaft using the detection signal by the encoder, resonance or semi-resonance in the running of the belt member, etc. occur, and the driven shaft is appropriately used in the conventional technique. In some cases, it became uncontrollable.

In the present embodiment, of the first motor 1 and the second motor 2 for driving the driven shaft 4 via the cogged belt 3, the encoder provided on the motor on the downstream side of the driven shaft 4 in the traveling direction of the cogged belt 3. Controls each drive of the first motor 1 and the second motor 2 based on the detection signal by.

More specifically, in the example of FIG. 1, when the cogged belt 3 travels in the CCW direction, each drive of the first motor 1 and the second motor 2 is controlled by using the first encoded signal ench1. On the other hand, when the cogged belt 3 travels in the CW direction, the drive of each of the first motor 1 and the second motor 2 is controlled by using the second encoded signal enc2.

By doing so, the driven shaft 4 can be controlled without using the detection signal by the encoder provided in the motor on the loose side of the cogged belt 3, so that the follow-up delay in the feedback control of the driven shaft 4 and the cogged belt 3 can be controlled. The driven shaft 4 can be appropriately controlled by preventing phenomena such as resonance and semi-resonance during traveling.

[Second Embodiment]
Next, the second embodiment will be described.

In the present embodiment, the control device 110a controls the drive system 100a that rotationally drives the driven shaft 4 via the cogged belt 3 using three motors, the first motor 1, the second motor 2, and the third motor 6. An example of doing so will be described.

FIG. 4 is a diagram illustrating an example of a configuration of a plurality of motors and a driven shaft according to the present embodiment. As shown in FIG. 4, the drive system 100a includes a third motor 6. The third motor 6 is provided between the first motor 1 and the second motor 2 around which the cogged belt 3 is wound. In the drive system 100a, the driven shaft 4 is rotationally driven via the cogged belt 3 by using the first motor 1, the second motor 2, and the third motor 6.

In the drive system 100a, when the cogged belt 3 travels in the CCW direction, the control device 110a is the first motor located downstream of the driven shaft 4 in the traveling direction of the cogged belt 3 and closest to the driven shaft 4. Each drive of the first motor 1, the second motor 2, and the third motor 6 is controlled based on the detection signal by the first encoder 13 provided in 1. On the other hand, when the cogged belt 3 travels in the CW direction, the control device 110a is provided on the second motor 2 located downstream of the driven shaft 4 in the traveling direction of the cogged belt 3 and closest to the driven shaft 4. Based on the detection signal by the second encoder 23, each drive of the first motor 1, the second motor 2 and the third motor 6 is controlled.

By doing so, the driven shaft 4 can be controlled without using the detection signal by the encoder provided in the motor on the loose side of the cogged belt 3, so that the follow-up delay in the feedback control of the driven shaft 4 and the cogged belt 3 can be controlled. The driven shaft 4 can be appropriately controlled by preventing phenomena such as resonance and semi-resonance during traveling.

In the above-described embodiment, the third motor 6 may or may not be provided with an encoder. When the third motor 6 is not provided with the encoder, the cost of the drive system 100a can be reduced.

Although the preferred embodiments and examples of the present invention have been described in detail above, the present invention is not limited to these embodiments and examples, and is within the scope of the gist of the present invention described in the claims. In, various modifications or changes are possible.

For example, in the above-described example, the control device 110 is applied to an image forming device or a conveying device, but in the embodiment, a plurality of motors are used to drive the same drive shaft via a belt member. It can be applied to any device as long as it is adopted.

As an example, the embodiment can be applied to a configuration in which a transport roller is driven in a transport device for transporting a sheet-shaped prepreg, bills, or the like. In addition, the embodiment can be applied to a configuration for the purpose of obtaining power by rotating a drive shaft driven via a belt member by using a plurality of motors in, for example, an automobile, a robot, an amusement machine, or the like.

Further, in the above-described embodiment, an example of a drive system including two and three motors has been shown, but the present invention is not limited to this, and four or more motors are used and driven via a belt member. The embodiment can also be applied when controlling the rotational drive of the shaft 4.

Further, in the above-described embodiment, the cogged belt 3 is shown as an example of the belt member, but the present invention is not limited to this, and the drive system 100 including various types of belts such as a flat belt, a round belt, and a V belt. Against this, the present embodiment can be applied.

The embodiment also includes a control method. For example, the control method is a detection signal of an angle detection unit provided on a motor on the downstream side of the driven shaft in the traveling direction of the belt member among a plurality of motors for driving the driven shaft via the belt member. Based on the above, the step of controlling each drive of the plurality of motors is included. By such a control method, the same effect as that of the control device described above can be obtained.

The embodiment also includes a program. For example, the program uses the detection signal of the angle detection unit provided on the motor on the downstream side of the driven shaft in the traveling direction of the belt member among the plurality of motors that drive the driven shaft via the belt member. Based on this, the computer is made to execute a process of controlling each drive of the plurality of motors. With such a program, the same effect as that of the control device described above can be obtained.

Further, each function of the embodiment described above can be realized by one or a plurality of processing circuits. Here, the "processing circuit" in the present specification is a processor programmed to execute each function by software such as a processor implemented by an electronic circuit, or a processor designed to execute each function described above. It shall include devices such as ASIC (Application Specific Integrated Circuit), DSP (digital signal processor), FPGA (field programmable gate array) and conventional circuit modules.

1 1st motor 11 Motor shaft 12 Pulley 13 1st encoder (an example of angle detection unit)
2 2nd motor 21 Motor shaft 22 Pulley 23 2nd encoder (an example of angle detection unit)
3 Cogged belt (an example of belt member)
4 Driven shaft 5 Driven pulley 6 Third motor 100 Drive system 103, 104 Driver 110 Control device 111 Belt traveling direction detection unit (example of detection unit)
112 Encoder selection section (example of selection section)
113 Drive control unit (an example of drive control unit)
114, 115 PWM generator ench1 1st encoded signal (example of detection signal)
ench2 2nd encoded signal (example of detection signal)

JP-A-2005-092763

Claims (5)

Of the plurality of motors that drive the driven shaft via the belt member, the plurality of motors are based on detection signals from an angle detection unit provided on the motor on the downstream side of the driven shaft in the traveling direction of the belt member. A control device including a drive control unit that controls each drive of the motor. A detection unit that detects the traveling direction and
A selection unit for selecting a motor on the downstream side of the driven shaft based on the detection result by the detection unit is provided.
The drive control unit
The control device according to claim 1, wherein each drive of the plurality of motors is controlled based on a detection signal of an angle detection unit provided on the motor selected by the selection unit. The drive control unit
Of the plurality of motors, each drive of the plurality of motors is controlled based on a detection signal of an angle detection unit provided on the motor located at a position closest to the driven shaft on the downstream side of the driven shaft. The control device according to claim 1 or 2. Among the plurality of motors that drive the driven shaft via the belt member, the plurality of motors are based on the detection signals of the angle detection unit provided on the motor on the downstream side of the driven shaft in the traveling direction of the belt member. A control method including a step of controlling each drive of a motor. Among the plurality of motors that drive the driven shaft via the belt member, the plurality of motors are based on the detection signals of the angle detection unit provided on the motor on the downstream side of the driven shaft in the traveling direction of the belt member. A program that causes a computer to execute a process that controls each drive of a motor.

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