JP2016178860A - Control device, motor drive device, sheet conveyance device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the occurrences of rotational irregularities and abnormal sound of a motor in a configuration for generating a pseudo-encoder signal from a hall signal to perform motor control.SOLUTION: A control device according to this invention converts a magnetic pole phase signal representing a magnetic pole phase of a motor, and controls a motor drive part provided with a rotational position detection part for outputting a rotational position detection signal representing the rotation amount and rotation direction of an output shaft of the motor and having high resolution to the magnetic pole phase signal. The control device includes a control part for controlling power to be fed to the motor by the motor drive part on the basis of the rotational position detection signal and a target signal. The control part includes a control gain setting part for setting a control gain so as to deteriorate the responsiveness of a specific frequency corresponding to a pole number representing the number of magnetic poles of the motor and the target rotation number of the motor based on the target signal.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a control device, a motor driving device, a sheet conveying device, and an image forming apparatus.

  Conventionally, the technology that realized energy saving, resource saving, and miniaturization by mounting an optical encoder on an inner rotor type brushless DC motor and driving it by feedback control while maintaining the position / speed driving accuracy equivalent to that of a stepping motor. It has been. In this technology, the use of an optical encoder imposes limitations such that paper dust, dust, ink mist, etc. are likely to cause problems and that the upper limit of the operating temperature of the optical encoder becomes the upper limit of the temperature when the motor is used. Is done. An encoderless motor drive device that solves this problem and aims to reduce costs is an encoderless motor drive device that generates a pseudo encoder signal from a hall signal output from a hall element and performs motor control.

  For example, in Patent Document 1, a 2-channel encoder equivalent signal (pseudo-encoder signal) is generated based on a magnetic pole phase signal (Hall signal) that is output from a Hall element and represents a magnetic pole phase of a motor, and motor control is performed. Technology is disclosed.

  However, the pseudo encoder signal generated from the Hall element includes the number of magnet poles of the motor due to variations in the position of the Hall element and the magnet, the relative position shift between the Hall elements, and variations in the sensing point of the Hall element itself. Periodic fluctuations (periodic noise) of the signal related to. As a result, there is a problem that uneven rotation of the motor and noise are caused.

  In order to solve the above-described problems and achieve the object, the present invention converts a magnetic pole phase signal representing the magnetic pole phase of the motor to represent the rotation amount and the rotational direction of the output shaft of the motor, and the magnetic pole phase signal A control device for controlling a motor drive unit provided with a rotation position detection unit that outputs a rotation position detection signal with high resolution with respect to the motor drive unit based on the rotation position detection signal and a target signal Includes a control unit that controls electric power to be supplied to the motor, and the control unit is responsive to a specific frequency according to the number of poles representing the number of magnetic poles of the motor and the number of rotations of the motor. Includes a control gain setting unit that sets the control gain so that the value decreases.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the rotation nonuniformity of a motor and the generation | occurrence | production of noise can be suppressed in the structure which produces | generates a pseudo | simulation encoder signal from a Hall signal and performs motor control.

FIG. 1 is a diagram illustrating an example of a configuration of an image forming apparatus. FIG. 2 is a partially enlarged view of the process cartridge. FIG. 3 is a diagram illustrating an example of the configuration of the document conveying device. FIG. 4 is a diagram illustrating an example of a hardware configuration of the motor driving device. FIG. 5 is a diagram illustrating an example of a detailed configuration of the position / speed tracking control unit. FIG. 6 is a diagram illustrating the frequency characteristics of the round transfer function. FIG. 7 is a diagram illustrating a complementary sensitivity function in the case where feedback control is performed using the circular transfer function of FIG. FIG. 8 is a diagram illustrating an example of a notch filter. FIG. 9 is a diagram illustrating an example of a notch filter. FIG. 10 is a diagram illustrating a complementary sensitivity function when the circular transfer function of FIG. 6 is combined with the notch filter of FIG. FIG. 11 is a flowchart illustrating an example of processing by the control gain setting unit. FIG. 12 is a diagram illustrating an example of a detailed configuration of the position / speed tracking control unit according to the second embodiment. FIG. 13 is a diagram illustrating an example of a hardware configuration of the motor drive device according to the second embodiment. FIG. 14 is a diagram illustrating an example of a hardware configuration of a motor drive device according to a modification. FIG. 15 is a diagram illustrating an example of a detailed configuration of a position / speed tracking control unit according to a modification. FIG. 16 is a diagram for explaining a mechanism for measuring the encoder pulse speed. FIG. 17 is a diagram for explaining pulses output by the encoder. FIG. 18 is a diagram for explaining the FIR filter. FIG. 19 is a diagram for explaining the effect of performing the moving averaging process. FIG. 20 is a diagram illustrating an example in which the magnitude of the rotation speed unevenness is measured for each frequency. FIG. 21 is a diagram illustrating an example in which the 6th-order, 12th-order, and 18th-order components are attenuated using three notch filters. FIG. 22 is a diagram illustrating an example of the complementary sensitivity function. FIG. 23 is a diagram illustrating an example in which the attenuation shape of the notch filter is set so that the responsiveness between the 6th-order, 12th-order, and 18th-order components and the respective peripheral frequencies simultaneously decreases. FIG. 24 is a diagram illustrating an example of the complementary sensitivity function. FIG. 25 is a diagram illustrating an example of the configuration of the drive portion. FIG. 26 is a diagram illustrating an example of the configuration of the drive portion. FIG. 27 is a diagram illustrating an example of the configuration of the drive portion. FIG. 28 is a diagram illustrating an example of a detailed configuration of the position / speed tracking control unit according to the modified embodiment. FIG. 29 is a diagram illustrating an example of a hardware configuration of a motor drive device according to a modification.

  Hereinafter, embodiments of a control device, a motor driving device, a sheet conveying device, and an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a diagram illustrating an example of a configuration of an image forming apparatus 100 according to the present embodiment. As shown in FIG. 1, the image forming apparatus 100 generates toner images of yellow, magenta, cyan, and black (hereinafter referred to as “Y”, “M”, “C”, and “K”, respectively). The four process cartridges 6Y, 6M, 6C, and 6K are provided.

These process cartridges 6Y, 6M, 6C, and 6K use Y toner, M toner, C toner, and K toner of different colors as image forming agents, but the other configurations are the same. Each of the process cartridges 6Y, 6M, 6C, and 6K can be attached to and detached from the main body of the image forming apparatus 100, so that consumable parts can be replaced at a time, and are replaced when the end of the service life is reached.

Since the process cartridges 6Y, 6M, 6C, and 6K have the same configuration, the schematic configuration of the image forming apparatus 100 will be described by taking the process cartridge 6Y for generating a Y toner image as an example. FIG. 2 is a partially enlarged view in the vicinity of the process cartridge 6Y shown in FIG. In the following, reference is made to FIG. 2 together with reference to FIG.

  As shown in FIG. 2, the process cartridge 6Y includes a photosensitive drum 1Y as a latent image carrier, a drum cleaning device 2Y, a charge eliminating device (not shown), a charging device 4Y, a developing device 5Y, and the like.

  The charging device 4Y is a device that uniformly charges the surface of the photosensitive drum 1Y. The photosensitive drum 1Y is rotated clockwise in the drawing by the drum rotating mechanism, and the photosensitive drum 1Y rotates, whereby the charging device 4Y uniformly charges the surface of the photosensitive drum 1Y.

The uniformly charged surface of the photosensitive drum 1Y is exposed and scanned by the laser beam L to carry an electrostatic latent image for Y. The electrostatic latent image on the surface of the photoreceptor drum 1Y is developed into a Y toner image by the developing device 5Y using Y toner. The Y toner image on the surface of the photosensitive drum 1Y is intermediately transferred onto the intermediate transfer belt 8. This process is called an intermediate transfer process.

The drum cleaning device 2Y is a device that removes toner remaining on the surface of the photosensitive drum 1Y after the intermediate transfer process. The static eliminator is a device that neutralizes residual charges on the photoreceptor drum 1Y after cleaning. By this charge removal, the surface of the photosensitive drum 1Y is initialized and prepared for the next image formation.

Similarly, in the other process cartridges 6M, 6C, and 6K, M toner images, C toner images, and K toner images are formed on the photosensitive drums 1M, 1C, and 1K, respectively, on the intermediate transfer belt 8. Intermediate transfer.

  As shown in FIG. 1, an exposure device 7 is disposed below each process cartridge 6Y, 6M, 6C, 6K in the drawing.

  The exposure device 7 is a device for forming an electrostatic latent image on the surface of each of the photosensitive drums 1Y, 1M, 1C, and 1K described above. The exposure device 7 irradiates the respective photosensitive drums 1Y, 1M, 1C, and 1K in the process cartridges 6Y, 6M, 6C, and 6K with a laser beam L that is emitted based on information on an image to be formed. The surfaces of the drums 1Y, 1M, 1C, and 1K are exposed. By this exposure, Y electrostatic latent images, M electrostatic latent images, C electrostatic latent images, and K electrostatic latent images are formed on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K, respectively.

  The exposure apparatus 7 irradiates the photosensitive drum with a desired electrostatic potential by irradiating the photosensitive drum with a plurality of optical lenses and mirrors while scanning the laser light L emitted from the light source with a polygon mirror rotated by a motor. The latent images are formed on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K, respectively.

  As shown in FIG. 1, a sheet feeding means is disposed on the lower side of the exposure apparatus 7 in the drawing. The paper supply means includes a paper storage cassette 26, a paper supply roller 27 incorporated in the paper storage cassette 26, a registration roller pair 28, and the like.

  The paper storage cassette 26 stores a plurality of sheets 99 as recording materials, and a paper feed roller 27 is in contact with the uppermost sheet 99. When the paper feeding roller 27 is rotated counterclockwise in the drawing by the driving mechanism, the uppermost paper 99 is fed toward the rollers of the registration roller pair 28.

  The registration roller pair 28 rotationally drives both rollers so as to sandwich the paper 99, but temporarily stops rotating immediately after sandwiching. Then, the sheet 99 is sent out toward a secondary transfer nip described later at an appropriate timing.

  On the other hand, as shown in FIG. 1, an intermediate transfer unit 15 is disposed above the process cartridges 6Y, 6M, 6C, and 6K. Has been.

  The intermediate transfer unit 15 includes a belt cleaning device 10 in addition to the intermediate transfer belt 8. Also provided are four primary transfer bias rollers 9Y, 9M, 9C, 9K, a secondary transfer backup roller 12, a cleaning backup roller 13, a tension roller 14, and the like.

  The intermediate transfer belt 8 is endlessly moved in the counterclockwise direction in the figure by the rotational drive of at least one roller while being stretched around the seven rollers. The primary transfer bias rollers 9Y, 9M, 9C, and 9K respectively sandwich the intermediate transfer belt 8 with the photosensitive drums 1Y, 1M, 1C, and 1K to form primary transfer nips. In other words, the primary transfer bias rollers 9Y, 9M, 9C, and 9K are arranged on the opposite side of the photosensitive drums 1Y, 1M, 1C, and 1K via the intermediate transfer belt 8, and the toner and the intermediate transfer belt 8 are in contact with toner. Applies a transfer bias of reverse polarity (for example, positive polarity).

  All the rollers except the primary transfer bias rollers 9Y, 9M, 9C, and 9K are electrically grounded. The intermediate transfer belt 8 sequentially passes through the primary transfer nips for Y, M, C, and K along with the endless movement thereof, and the Y toner images on the respective photosensitive drums 1Y, 1M, 1C, and 1K. The M toner image, the C toner image, and the K toner image are superimposed and primarily transferred. As a result, a four-color superimposed toner image (hereinafter referred to as “four-color toner image”) is formed on the intermediate transfer belt 8.

  Further, the secondary transfer backup roller 12 sandwiches the intermediate transfer belt 8 between the secondary transfer roller 19 and forms a secondary transfer nip. The four-color toner image formed on the intermediate transfer belt 8 is transferred to the paper 99 at the secondary transfer nip. Then, combined with the white color of the paper 99, a full color toner image is obtained.

  Untransferred toner that has not been transferred to the paper 99 adheres to the intermediate transfer belt 8 after passing through the secondary transfer nip. The transfer residual toner is cleaned by the belt cleaning device 10. In the secondary transfer nip, the sheet 99 is sandwiched between the intermediate transfer belt 8 whose surface moves in the forward direction and the secondary transfer roller 19 and is conveyed in the opposite direction to the registration roller pair 28 side.

  The sheet 99 fed from the secondary transfer nip is affected by heat and pressure when passing between the rollers of the fixing unit 20 as a detachable unit with respect to the image forming apparatus 100 main body. The toner image is fixed. Thereafter, the sheet 99 is discharged out of the image forming apparatus 100 through the rollers of the pair of discharge rollers 29.

  A stack unit 30 is formed on the upper surface of the casing of the main body of the image forming apparatus 100, and the sheets 99 discharged out of the apparatus by the discharge roller pair 29 are sequentially stacked on the stack unit 30.

  As shown in FIG. 1, a bottle support portion 31 is disposed between the intermediate transfer unit 15 and the stack portion 30 located above the intermediate transfer unit 15. To the bottle support portion 31, toner bottles 32Y, 32M, 32C, and 32K are set as agent containers for storing the respective color toners.

  The color toners in the toner bottles 32Y, 32M, 32C, and 32K are appropriately supplied to the developing devices of the process cartridges 6Y, 6M, 6C, and 6K by the toner supply devices. The toner bottles 32Y, 32M, 32C, and 32K are detachable from the main body of the image forming apparatus 100 independently of the process cartridges 6Y, 6M, 6C, and 6K.

  FIG. 3 is a diagram showing an example of the configuration of a document conveying apparatus 101 (an example of a sheet conveying apparatus) that is used in addition to the image forming apparatus 100 described above. The document conveying apparatus 101 is disposed on the upper part of the image forming apparatus 100 shown in FIG. 1, and the image forming apparatus 100 and the document conveying apparatus 101 function as a copier, MFP, or the like. Therefore, the image forming apparatus 100 to which the document conveying apparatus 101 is added is also referred to as the image forming apparatus 100 without distinction.

  A document conveying apparatus 101 shown in FIG. 3 is applied to a read document processing apparatus (hereinafter referred to as ADF) that conveys a document to be read to a fixed reading device unit and reads an image while conveying the document at a predetermined speed. Is.

  The document conveying apparatus 101 includes an original setting unit A for setting a read original bundle, a separation feeding unit B for separating and feeding originals one by one from the set original bundle, and abutting alignment of the fed originals Then, the registration unit C that pulls out and conveys the document after alignment, the turn unit D that turns the conveyed document and conveys the document surface toward the reading side (downward), and displays the surface image of the document below the contact glass. A first reading / conveying unit E for performing reading, a second reading / conveying unit F for reading a back side image of a document after reading, a paper discharge unit G for discharging a document whose front and back have been read out of the machine, A stack portion H for stacking and holding documents is provided. The document conveying apparatus 101 includes a pickup motor, a sheet feeding motor, a reading motor, a sheet discharging motor, a bottom plate raising motor, and the like as a driving source for driving the conveying operation.

  The document table 42 includes a movable document table 43, and a sheet 99 to be read is set. The sheet 99 is set on the document table 42 with the document surface facing upward. The document table 42 includes a side guide, and the width direction of the sheet 99 is positioned in a direction orthogonal to the transport direction. The set paper 99 is detected by the set filler 44 and the set sensor 45 and transmitted to the main body control unit.

  Document length detection sensors 70 and 71 (a reflection type sensor or an actuator type sensor that can be detected even on 99 sheets of paper) are arranged on the document table 42. Document length detection sensors 70 and 71 determine the length of the document in the conveyance direction. At this time, the document length detection sensors 70 and 71 are arranged so as to be able to determine at least whether the document size is vertical or horizontal.

  The movable document table 43 can be moved up and down in the directions of arrows a and b by a bottom plate raising motor. When the set filler 44 and the set sensor 45 detect that the original is set on the movable original table 43, the bottom plate raising motor is rotated forward so that the uppermost surface of the original bundle comes into contact with the pickup roller 47. Raise. In FIG. 3, the ascending state is indicated by a solid line.

  The pickup roller 47 is moved in the directions of arrows c and d by a cam mechanism by a pickup motor, and the movable document table 43 is raised and pushed by the upper surface of the document on the movable document table 43 to rise in the c direction, and the table rise detection sensor 48. The upper limit can be detected.

  The paper feeding belt 49 is driven in the paper feeding direction by the normal rotation of the paper feeding motor, and the reverse roller 50 is driven to rotate in the reverse direction to the paper feeding by the normal rotation of the paper feeding motor. In this configuration, only the uppermost document can be fed.

  The reverse roller 50 is in contact with the paper feed belt 49 at a predetermined pressure, and when two or more originals enter between the paper feed belt 49 and the reverse roller 50, the reverse roller 50 rotates in the clockwise direction, which is the original driving direction, and is redundant. This function pushes back the original and prevents double feeding of the original.

  The original separated by the action of the paper feeding belt 49 and the reverse roller 50 is further fed by the paper feeding belt 49, and the leading edge is detected by the abutting sensor 51 and further abuts against the pull-out roller 52 stopped. . Thereafter, the paper feed motor is stopped while being fed by a predetermined distance from the detection of the abutting sensor 51 and, as a result, is pressed against the pull-out roller 52 with a predetermined amount of deflection. As a result, the driving of the paper feeding belt 49 is stopped.

  At this time, the pickup motor 47 is retracted from the upper surface of the document by rotating the pickup motor, and the document is fed only by the conveying force of the paper feed belt 49, so that the leading edge of the document enters the nip of the upper and lower rollers of the pull-out roller 52. Then, tip alignment (skew correction) is performed.

  The pull-out roller 52 has a skew correction function and conveys the skew-corrected document after separation to the intermediate roller 54, and is driven by the reverse rotation of the paper feed motor. Note that the pull-out roller 52 and the intermediate roller 54 are driven at the time of reverse rotation of the paper feed motor, but the pickup roller 47 and the paper feed belt 49 are not driven.

  A plurality of document width sensors 53 are arranged in the depth direction and detect the size in the width direction perpendicular to the transport direction of the document transported by the pull-out roller 52. The length of the document in the conveyance direction is detected by a motor pulse by reading the leading edge and the trailing edge of the document with an abutment sensor 51.

  When the document is transported from the resist section C to the turn section D by driving the pull-out roller 52 and the intermediate roller 54, the transport speed at the resist section C is set to be higher than the transport speed at the first reading transport section E. Thus, the processing time for sending the document to the reading unit is shortened.

  When the leading edge of the document is detected by the reading inlet sensor 55, the reading motor is driven forward to drive the reading inlet roller 56, the reading outlet roller 63, and the CIS outlet roller 67.

  When the leading edge of the document is detected by the registration sensor 57, the document sensor decelerates over a predetermined conveyance distance, temporarily stops before the reading position 60 where the first reading unit (not shown) is arranged, and the main body control unit receives I. A stop signal is transmitted via / F.

  Subsequently, when a reading start signal is received from the main body control unit, the stopped document is transported at an increased speed so as to rise to a predetermined transport speed until the leading end of the document reaches the reading position.

  At the timing when the leading edge of the document detected by the pulse count of the reading motor reaches the reading section, a gate signal indicating the effective image area in the sub-scanning direction on the first surface is sent to the main body control section, and the first reading section is moved to the trailing edge of the document. Sent until is removed.

  In the case of reading a single-sided document, the document that has passed through the first reading and conveying unit E is conveyed to the paper discharge unit G through the second reading unit 65. At this time, when the leading edge of the document is detected by the paper discharge sensor 64, the paper discharge motor is driven to rotate forward to rotate the paper discharge roller 68 counterclockwise.

  Further, the discharge motor drive speed is reduced immediately before the trailing edge of the document comes out of the nip between the upper and lower roller pairs of the discharge roller 68 by the discharge motor pulse count from the detection of the leading edge of the document by the discharge sensor 64 to discharge the sheet. Control is performed so that the document discharged onto the tray 69 does not jump out.

  The surface of the second reading unit 65 is provided with a coating member that has been subjected to a coating process in order to prevent vertical streaks indicating image defects caused by transfer of glue-like material attached to the document onto the reading line. Yes.

  This coating member is formed by applying a coating material having a dirt decomposition function or a hydrophilic coating material to the reading surface of the second reading unit 65. These coating materials can use a well-known thing.

  FIG. 4 is a diagram illustrating an example of a hardware configuration (circuit configuration) of the motor driving device 210 that drives the motor 200 of the present embodiment. The motor 200 can be used, for example, for driving the paper feed roller 27 of the main body of the image forming apparatus 100 shown in FIG. Further, for example, it can be used for driving the reading entrance roller 56, the reading exit roller 63, or the CIS exit roller 67 of the document conveying apparatus 101 shown in FIG. These rollers (conveyance rollers) are an example of a conveyance member for conveying a sheet (in this example, a sheet, but not limited thereto).

  The motor 200 of this embodiment is a three-phase drive brushless DC motor. That is, the motor 200 is an electric motor that does not have a commutator and whose direction of magnetic pole is switched by switching a direct current supplied from the motor driving device 210 by an FET (an example of a semiconductor switch) 201. The motor 200 includes a Hall element 202 that outputs a magnetic pole phase signal (also referred to as a “Hall signal”) indicating the magnetic pole phase of the motor 200. In this example, since the motor 200 is a three-phase drive, it includes three Hall elements 202 to feed back the magnetic pole phase signal.

  As shown in FIG. 4, the motor driving device 210 includes a motor driving unit 220 that supplies electric power to the motor 200 and a control device 230 that controls the motor driving unit 220.

  First, the motor drive unit 220 will be described. As shown in FIG. 4, the motor drive unit 220 includes a power supply unit 221 and a rotational position detection unit 222.

  The power supply unit 221 supplies power to the motor 200 under the control of the control device 230. More specifically, the power supply unit 221 supplies power to the motor 200 in accordance with control signals (control signals for instructing PWM output, rotation direction, start, stop, brake, etc.) supplied from the control device 230.

  The rotational position detection unit 222 converts the magnetic pole phase signal representing the magnetic pole of the motor 200 to represent the rotation amount and the rotational direction of the output shaft of the motor 200, and provides a rotational position detection signal with high resolution with respect to the magnetic pole phase signal. Output. More specifically, the rotational position detector 222 generates a signal representing the rotational position of the output shaft of the motor 200 from the Hall signal (magnetic pole phase signal) obtained from the Hall element 202. This signal is a signal equivalent to a two-channel encoder signal when a rotary encoder is provided on the output shaft of the motor 200 (hereinafter sometimes referred to as an “encoder equivalent signal”). The rotational position detection unit 222 can generate a 2-channel encoder equivalent signal using, for example, the technique disclosed in Japanese Patent Application Laid-Open No. 2015-19563.

  Next, the control device 230 will be described. As illustrated in FIG. 4, the control device 230 includes a control unit 231. The control unit 231 is based on the encoder equivalent signal (rotational position detection signal) output from the rotational position detection unit 222 of the motor driving unit 220 and the target signal output from the external target signal generation unit 240. Controls the power to be supplied to the motor 200.

  As shown in FIG. 4, the control unit 231 includes a motor position / speed calculation unit 232, a target position / speed calculation unit 233, and a position / speed tracking control unit 234. In this embodiment, the motor position / speed calculation unit 232, the target position / speed calculation unit 233, and the position / speed tracking control unit 234 are configured by dedicated hardware circuits (for example, semiconductor integrated circuits). For example, it can be realized by software. For example, the control device 230 has a hardware configuration equivalent to that of a computer device such as a CPU, ROM, and RAM, and the CPU executes a program stored in the ROM or the like, whereby a motor position / speed calculation unit 232, a target position, and the like. The functions of the speed calculation unit 233 and the position / speed tracking control unit 234 can also be realized.

  The motor position / speed calculation unit 232 receives a 2-channel encoder equivalent signal (rotation position detection signal) from the rotation position detection unit 222 in the motor drive unit 220, and calculates the rotation direction and the number of movement pulses of the output shaft of the motor 200. get. Since the 2-channel encoder equivalent signal is a 2-channel signal having a constant phase difference (90 ° in the present embodiment) whose output changes according to the rotation angle of the output shaft of the motor 200, the motor position / speed calculation unit 232 Using this phase difference, the rotation direction of the output shaft of the motor 200 and the number of moving pulses can be obtained. The motor position / speed calculation unit 232 derives the rotation position and rotation speed (rotation speed) of the motor 200 from the rotation direction and the number of movement pulses of the output shaft of the motor 200 and the time signal of the oscillator included in the control device 230. Then, the rotation position information indicating the derived rotation position and the speed information indicating the derived rotation speed are transmitted to the position / speed tracking control unit 234.

  The target position / velocity calculation unit 233 obtains, from the external target signal generation unit 240, rotation direction information indicating the rotation direction of the motor 200 and pulse information indicating the number of moving pulses as target signals. Then, the target position / speed calculation unit 233 derives the target position and target speed (target rotational speed) of the motor 200 from the obtained target signal and the time signal of the oscillator included in the control device 230, and determines the target position. The target position information indicating the target speed and the target speed information indicating the target speed are transmitted to the position / speed tracking control unit 234.

  The position / speed tracking control unit 234 matches the target position information and target speed information acquired from the target position / speed calculation unit 233 with the rotational position information and speed information acquired from the motor position / speed calculation unit 232, respectively. , A PWM signal instructing the PWM output is generated. In the present embodiment, the position / speed tracking control unit 234 includes a control gain setting unit 235. The control gain setting unit 235 sets the control gain so that the response of a specific frequency corresponding to the number of poles representing the number of magnetic poles of the motor and the target rotational speed of the motor based on the target signal is lowered. In this example, the control gain setting unit 235 obtains pole number information indicating the number of poles from the memory in the control device 230 or from the outside, and from the target position / speed calculation unit 233, the target speed information (shows the target rotation number). Information). And the specific frequency according to the pole number which the acquired pole number information shows, and the target rotation speed which target speed information shows is determined. Specific contents will be described later.

  FIG. 5 is a diagram illustrating an example of a detailed configuration of the position / speed tracking control unit 234. As shown in FIG. 5, the position / velocity tracking control unit 234 includes a comparison unit 251, a multiplication unit 252, a differentiation unit 253, a comparison unit 254, a PID calculation unit 255, a differentiation unit 256, and an addition unit 257. And a control gain setting unit 235 and a PWM signal generation unit 236.

  The comparison unit 251 receives target position information input from the target position / speed calculation unit 233 (input in a cycle corresponding to a predetermined sampling frequency) and input from the motor position / speed calculation unit 232 (according to a predetermined sampling frequency). Position deviation information indicating a difference from the rotational position information input in a cycle is generated, and the generated position deviation information is output to the multiplication unit 252. The multiplication unit 252 multiplies the position deviation information input from the comparison unit 251 by a certain gain (P control) to generate position feedback information (position FB), and outputs the generated position feedback information to the comparison unit 254. To do.

  Further, the differentiating unit 253 differentiates the target position information input from the target position / velocity calculating unit 233 (input at a cycle corresponding to a predetermined sampling frequency) to generate position feedforward information (position FF), The generated position feedforward information is output to the comparison unit 254. In the example of FIG. 5, the speed information from the motor position / speed calculation unit 232 is also input to the comparison unit 254 (input in a cycle corresponding to a predetermined sampling frequency).

  The comparison unit 254 subtracts the speed information input from the motor position / speed calculation unit 232 from the result of adding the position feedback information input from the multiplication unit 252 and the position feedforward information input from the differentiation unit 253. Thus, the speed deviation information indicating the speed deviation is generated, and the generated speed deviation information is output to the PID calculation unit 255. The PID calculation unit 255 performs PID calculation (P: proportionality, I: integration, D: differentiation) on the input speed deviation information, and speed feedback information (information representing the acceleration of the motor 200, in other words, the motor And the generated speed feedback information (speed FB) is output to the adder 257.

  On the other hand, the differentiation unit 256 differentiates the target speed information input from the target position / velocity calculation unit 233 to obtain speed feedforward information (information representing the acceleration of the motor 200, in other words, information representing the torque of the motor 200). And the generated speed feedforward information (speed FF) is output to the adding unit 257.

  The adder 257 adds the input speed feedback information and the speed feedforward information, and adds a control deviation (in other words, a control deviation based on the target signal and the rotational position detection signal input to the control device 230). Motor control information for generating zero (which can be considered to be) is generated. In this example, the motor control information obtained by the addition by the addition unit 257 can be considered as information indicating an output command value (power command value) of the motor 200 for making the control deviation zero. The adding unit 257 outputs the generated motor control information to the control gain setting unit 235.

  The control gain setting unit 235 performs a process of attenuating a specific frequency component (for example, a process of removing a specific frequency component is included) on the motor control information input from the adder 257. Specific contents will be described later. The motor control information that has been processed by the control gain setting unit 235 is output to the PWM signal generation unit 236. The PWM signal generation unit 236 generates a signal (PWM signal) indicating a voltage for driving the motor 200 according to the motor control information input from the control gain setting unit 235, and outputs the generated PWM signal to the motor drive unit. To 220.

  Here, as in this embodiment, an encoder equivalent signal is generated based on a Hall signal output from the Hall element 202 without mounting an encoder, and the motor 200 is driven, which corresponds to three phases. The waveforms of the two Hall signals are out of phase due to the dislocation between the Hall elements 202. Since the Hall element 202 is a sensor that detects the magnetic force of the motor magnet, for example, in a 12-pole motor 200 that constitutes a combination of 6 pairs of NS, a 6-cycle wave is generated. As a result, in the three-phase 12-pole motor 200, the 6th, 12th, 18th, and 36th frequency components when one rotation of the motor 200 is completed are caused by sensor noise (periodic variation of the encoder equivalent signal). Rotation unevenness and noise occur.

  In the present embodiment, when the number of poles of the motor 200 is p and the target rotational speed is N, rotational unevenness due to sensor noise occurs significantly at a frequency that is an integral multiple of p / 2 × N / 60. The control gain setting unit 235 sets the control gain so that the response of a specific frequency corresponding to the number of poles representing the number of magnetic poles of the motor and the target rotational speed (target speed) of the motor is lowered. Set (in other words, control is performed to attenuate the control gain for a specific frequency). More specifically, the control gain setting unit 235 sets the control gain so that the response of a frequency (specific frequency) that is an integral multiple of p / 2 × N / 60 is lowered. Thereby, generation | occurrence | production of the rotation nonuniformity and noise resulting from sensor noise can be suppressed.

  As described above, the control gain setting unit 235 sets a specific frequency (an integer multiple of p / 2 × N / 60) with respect to the motor control information representing the output command value of the motor 200 for setting the control deviation to zero. The frequency component is attenuated. That is, the control gain setting unit 235 variably sets a specific frequency according to the number of poles representing the number of magnetic poles of the motor 200 and the target rotation number of the motor 200, and the motor control input from the adder 257. Data processing that realizes a function of a filter (notch filter) for attenuating a set specific frequency component is performed on the information by software.

  Therefore, unlike the conventional analog PLL control, there is no need to provide an analog electronic circuit corresponding to each of a plurality of rotation speeds and a harness for selecting a gain for each of a plurality of rotation speeds. Complexity and cost increase can be suppressed. The control gain setting unit 235 of the present embodiment uses the motor control information input from the addition unit 257 as a data processing target. However, the data processing target by the control gain setting unit 235 is not limited to this. . In short, the control gain setting unit 235 controls the control gain (control device) so that the response of a specific frequency corresponding to the number of poles representing the number of magnetic poles of the motor and the target rotational speed (target speed) of the motor is lowered. 230 can be considered to be a ratio between the input to the output 230 and the output.

  Here, the number of poles of the motor 200 is defined by the variable p. However, since the number of poles is not changed when the motor 200 is fixed, the pole number information is set as a constant in the control gain setting unit 235. It may be incorporated in the calculation formula. The notch filter (data processing that realizes the function of the notch filter) may be targeted for the 6th, 12th, and 18th orders, which have a large contribution to rotation unevenness and noise. A method of attenuation by a filter (data processing that realizes a function of a low-pass filter) may be used. This is because as the number of notch filters increases, the calculation time load increases. In addition, when the notch filter is formed digitally, the notch may be shifted from the target frequency due to a digital error. Therefore, it is preferable that the notch has a width. Furthermore, the adaptive rotation speed of the notch filter may be applied to all rotation speeds depending on the rotation speed, or may be applied to a specific rotation speed. Note that the setting of the attenuation factor of the notch filter is arbitrarily possible according to the corresponding frequency component. The attenuation rate is determined in consideration of a phase margin and the like by obtaining a required attenuation rate from the rotation unevenness of each frequency component and the target rotation unevenness after attenuation.

  FIG. 6 is a diagram illustrating the frequency characteristics of a round transfer function representing the relationship between the input to the control unit 231 and the output when the control gain setting unit 235 is not provided, and FIG. 7 is a round trip transfer of FIG. It is a figure showing the complementary sensitivity function at the time of performing feedback control with a function. That is, FIG. 7 can be considered as a diagram showing the response to the target value and sensor noise. In this example, the crossover frequency (control band) indicating the frequency at which the absolute value of the circuit transfer function is 1 (ratio of input to output is 1, that is, gain 0) is 60 Hz. It turns out that falls. Although a method of lowering the responsiveness in a frequency band exceeding the crossing frequency by lowering the crossing frequency is conceivable, this method leads to deterioration of target followability and responsiveness to a disturbance load. Therefore, the control gain setting unit 235 of the present embodiment does not change the crossing frequency, and sets the control gain so as not to reduce the responsiveness of a specific frequency included in the frequency band equal to or lower than the crossing frequency (in other words, Then, the control gain for a specific frequency included in the frequency band below the crossing frequency is set to 0 or more). Since the crossover frequency is determined by design according to the system requirements (target followability, disturbance suppression, etc.) of the control target, the crossover frequency may be 60 Hz or 30 Hz as a result.

  Note that the phase rotates when the crossing frequency and the notch filter frequency are close, and the gain rises to 1 or more near the crossing frequency. Therefore, the frequency of the notch filter is preferably separated by 1.5 times or more of the crossing frequency.

  In paper conveyance using a plurality of motors 200 and conveyance members (conveyance rollers), it is common to set the cross frequency in common. Otherwise, the target followability in acceleration / deceleration will be different, and the paper between the independently driven transport rollers will be bent or pulled to generate noise and damage the paper, so avoid it Therefore, the crossing frequency is common. In addition, even if the crossing frequency is different in the conveyance between rollers that conveys in a state where a certain deflection is formed, the deflection can be used because it acts as a buffer that absorbs the difference in target followability.

  Here, as an example, it is assumed that the target rotational speed of the three-phase 12-pole motor 200 is 2400 rpm. In this case, since p = 12, N = 2400, the specific frequency is an integer multiple of 12/2 × 2400/60 = 240 Hz, and the control gain setting unit 235 receives the motor input from the addition unit 257. Data processing for realizing the function of the notch filter having the characteristics shown in FIG. 8 is performed on the control information.

  As another example, the responsiveness is reduced among specific frequencies (a plurality of frequencies that are integer multiples of p / 2 × N / 60) corresponding to the number of poles of the motor 200 and the target rotational speed of the motor 200. It is also possible to consider a form in which designation information for designating (for example, designating a number that is an integer multiple) one frequency (especially a frequency at which rotation unevenness is remarkable) is prepared (for example, stored in a memory in the control device 230). It is done. In this case, the control gain setting unit 235 includes the number of poles of the motor 200 indicated by the pole number information acquired from the memory in the control device 230 or from the outside, and the target speed indicated by the target speed information acquired from the target position / speed calculation unit 233. One frequency may be selected as a specific frequency based on (target rotational speed) and the above-described designation information, and the control gain may be set so that the responsiveness of the selected frequency is reduced. Note that the designation information described above may be information that designates two or more frequencies as specific frequencies.

  For example, when p = 12, N = 2400, and the above-described designation information specifies that the integer multiple is “2”, the control gain setting unit 235 displays 12/2 × 2400/60 × 2. = 480 Hz is selected as the specific frequency, and the control gain is set so that the response of the selected specific frequency is reduced. In this case, the control gain setting unit 235 performs data processing for the motor control information input from the adding unit 257 so as to realize the function of a notch filter having characteristics as shown in FIG. The complementary sensitivity function in this case is expressed as shown in FIG.

  FIG. 11 is a flowchart illustrating an example of processing by the control gain setting unit 235. The control gain setting unit 235 repeatedly executes the process of FIG. 11 at a cycle according to a predetermined sampling frequency. As shown in FIG. 11, the control gain setting unit 235 acquires the target speed information input from the target position / speed calculation unit 233 (step S1). Next, the control gain setting unit 235 acquires pole number information from the memory in the control device 230 or from the outside (step S2). Next, the control gain setting unit 235 sets a specific frequency according to the target speed (target rotational speed) indicated by the target speed information acquired in step S1 and the pole number indicated by the pole number information acquired in step S2. Set (step S3). The specific contents are as described above. Next, the control gain setting unit 235 performs a process of attenuating the specific frequency component set in step S3 on the motor control information input from the adding unit 257 (step S4), and the process is performed. The motor control information is output to the PWM signal generation unit 235 at the subsequent stage.

  As described above, in the present embodiment, the control for controlling the electric power that the motor drive unit 220 should supply to the motor 200 based on the encoder equivalent signal (rotation position detection signal) obtained by converting the Hall signal and the target signal. The unit 231 is a control gain setting unit that sets a control gain so that the response of a specific frequency corresponding to the number of poles representing the number of magnetic poles of the motor and the target rotational speed of the motor 200 based on the target signal is reduced. 235. As described above, in the present embodiment, when the number of poles of the motor 200 is p and the target rotational speed is N, rotation unevenness due to sensor noise occurs at a frequency that is an integral multiple of p / 2 × N / 60. Focusing on the conspicuous occurrence, the control gain is set so that the response of a frequency (specific frequency) that is an integer multiple of p / 2 × N / 60 is lowered. Thereby, generation | occurrence | production of the rotation nonuniformity and noise resulting from sensor noise can be suppressed.

(Second Embodiment)
Next, a second embodiment will be described. Description of parts common to the above-described first embodiment will be omitted as appropriate. The control gain setting unit 235 of the present embodiment has a specific frequency response that decreases according to the number of poles representing the number of magnetic poles of the motor 200 and the actual number of rotations (actual rotation speed) of the motor 200. Set the control gain to More specifically, the control gain setting unit 235 synchronizes with the rotational position of the motor 200, and the above rotational position information indicating the rotational position of the motor 200 or the above speed information indicating the rotational speed of the motor 200 (described above). (Rotational position information or speed information based on the rotational position detection signal) is sampled, and the above-mentioned specific frequency component is reduced. The control gain setting unit 235 performs software data processing that realizes a function of a filter (notch filter) that attenuates a specific frequency component of the sampled rotational position information or speed information.

  As shown in FIG. 12, in this embodiment, the rotational position information input from the motor position / speed calculation unit 232 (input at a cycle corresponding to a predetermined sampling frequency) is filtered by the control gain setting unit 235. Is input to the comparison unit 251. In the present embodiment, the speed information input from the motor position / speed calculator 232 (input at a cycle corresponding to a predetermined sampling frequency) is filtered by the control gain setting unit 235 and then the comparison unit 254. Is input. In this example, as shown in FIG. 13, the control gain setting unit 235 is provided inside the position / speed tracking control unit 234. However, the present invention is not limited to this. For example, as shown in FIG. The gain setting unit 235 may be provided outside the position / speed tracking control unit 234.

  For example, as shown in FIG. 15, the rotational position information input from the motor position / speed calculation unit 232 (input at a cycle according to a predetermined sampling frequency) is input to the comparison unit 251 as it is, and the motor position / speed is input. The speed information input from the calculation unit 232 (input in a cycle corresponding to a predetermined sampling frequency) may be input to the comparison unit 254 after being filtered by the control gain setting unit 235.

  In short, the control gain setting unit 235 has a function of setting the control gain so that the response of a specific frequency is lowered according to the number of poles representing the number of magnetic poles of the motor 200 and the number of rotations of the motor 200. What is necessary is just to have. “The rotational speed of the motor 200” may be the target rotational speed (target rotational speed) of the motor 200 based on the target signal as in the first embodiment described above. The actual rotational speed (actual rotational speed) of the motor 200 based on the rotational position detection signal may be used.

FIG. 16 is a diagram for explaining a mechanism for measuring the speed of each encoder pulse. In the example of FIG. 16, the speed of the encoder pulse is measured by counting how many reference clock signals are input with respect to the encoder pulse width. For example, a case is assumed in which the rotation speed is obtained when the motor 200 with an encoder of 100 pulses per revolution is rotating at N (rpm). If the reference clock f2 of the counter is 100 MHz (reference time t2 = 1 / f2), the measured encoder 1 pulse time is t1, and the counted number of the measured reference clock is n, n = t1 / t2, N = 60 / (N × t2) × 1/100 (pulse), t2 = 1 / f2 = 10 ⁻⁸ (s). Assuming that n = 60000 counts, t1 = n × t2 = 60000 × 1 / f2 = 0.006 (s) and N = 60 / t1 / 100 = 1000 (rpm).

  FIG. 17 is a diagram for explaining pulses output by the encoder. Usually, the encoder outputs two types of pulse trains. CH A and CH B. The feature of the encoder is that the direction can be identified by having two channels. The interval from the rising edge of CH A to the next rising edge is 1 times the basic pulse width of the encoder pulse. Using the combination of rising and falling of CH A and CH B, the minimum pulse width (multiplication by 4) can be found. Which one is used is arbitrary, but for example, it is generally performed to use 1 multiplication during high speed rotation and 4 multiplication for low speed or stop / hold. Therefore, when the number of pulses at one rotation of the motor is used in the filter calculation, it is necessary to pay attention to whether the driving is one multiplication or four multiplication.

  Here, considering the resolution n (pulse / circumference) of the encoder and the number of poles p of the motor 200, it can be seen that rotation unevenness occurs at 1 / integer multiple of the number of taps a = n / (p / 2). Independent of speed. Therefore, it is desirable to sample at the timing of the number of taps. There is a merit that the parameter design of the gain control unit 235 can be made with an arbitrary (independent) motor rotation speed. For example, in the case of a 12-pole motor, if p = 12 and encoder resolution n = 360 pulses, N = 360 / (12/2) = 60 pulses, and the number of taps is 60 pulses, 30 pulses, and 15 pulses. It can be seen that the generated frequencies correspond to the 6th-order frequency component, the 12th-order frequency component, and the 18th-order frequency component. Therefore, by configuring a digital filter that samples position / velocity information at the timing using these tap numbers, it is possible to suppress rotation unevenness due to sensor noise. The simplest example is to perform a moving averaging process every 60 pulses. Thereby, the sixth-order frequency component can be made zero regardless of the rotation speed. Similarly, the 12th-order frequency component can be attenuated by performing the moving averaging process every 30 pulses. For example, if an FIR filter is used, it is possible to cope with an attenuation factor, a corresponding frequency, and a plurality of frequencies, which is preferable to the case of performing a simple moving average process.

  FIG. 18 is a diagram for explaining the FIR filter of the digital filter. D represents data measured by a counter for each pulse, and represents a mechanism for processing every N pieces. Each data is set with weighting coefficients a0 to a (n-1). This coefficient is a value corresponding to 1 / N when N pieces of data are used, and is sequentially added N times.

  FIG. 19 is a diagram for explaining the effect of performing the moving averaging process. The example of FIG. 19 represents the case where the coefficient is 1 and N = 30. The original data is composed of a 6th-order frequency component that changes with a period of 60 pulses, a 12th-order frequency component that changes with a period of 30 pulses, and an 18th-order frequency component that changes with a period of 15 pulses. is there. On the other hand, the result of adding an averaging process for every 30 pulses for removing the 12th-order frequency component is shown. It can be seen that the 12th-order frequency component, which is the cause of the largest amplitude, is greatly attenuated by the effect of the averaging filter. By performing filter processing on the rotational position information and speed information after counting the encoder pulses, data processing can be performed on the upstream side independent from the position / speed tracking control unit 234. There is an advantage that it can be set independently without being affected by the calculation speed of the control unit 234 and the memory capacity. By applying the filter process to the information that is the basis of the speed control and the position control, the effect of the filter process can be exerted on both the speed control and the position control.

(Third embodiment)
Next, a third embodiment will be described. FIG. 20 is an example in which the magnitude of unevenness in rotational speed when FFT processing is performed on a pseudo encoder signal at a certain rotational speed is measured for each frequency. In addition to the frequency component (primary component) of one rotation of the motor 200, the rotation unevenness is large in the sixth, twelfth, eighteenth and twenty-fourth components. Since the motor 200 used for the measurement is a 12-pole motor having the number of poles p = 12, the rotation unevenness is large at an integral multiple of p / 2 as described in the first embodiment. In addition, a small rotation unevenness component is recognized as an integer multiple of the primary component. If these rotation irregularities are also stacked, they cause a large rotation irregularity and noise.

  Therefore, in the present embodiment, the control gain setting unit 235 sets the control gain so that the responsiveness between the above-described specific frequency and the peripheral frequency of the specific frequency simultaneously decreases. The control gain setting unit 235 is a mode for performing a process (filtering process) for simultaneously attenuating components of a specific frequency and a peripheral frequency with respect to the motor control information, as in the first embodiment. Alternatively, as in the second embodiment described above, a process (filtering process) for simultaneously attenuating specific frequency and peripheral frequency components is performed on the rotational position information or speed information based on the rotational position detection signal. Form may be sufficient.

  FIG. 21 is a diagram illustrating an example in which the 6th-order, 12th-order, and 18th-order components are attenuated using three notch filters. In the example of FIG. 21, the 11th and 13th components have almost no attenuation effect with respect to the 12th order, the 5th and 7th components have almost no attenuation effect with respect to the 6th order, and the 17th and 19th orders with respect to the 18th order. The next component has almost no damping effect. The complementary sensitivity function in this case is expressed as shown in FIG.

  FIG. 23 is a diagram illustrating an example in the case where the attenuation shape of the notch filter is set so that the responsiveness between the 6th-order, 12th-order, and 18th-order components and the respective peripheral frequencies simultaneously decreases in the present embodiment. . In the example of FIG. 23, the attenuation shape of the notch filter for attenuating the 12th-order component is changed to a skirt-wide shape, thereby exerting an attenuation effect on a plurality of adjacent order components. In the example of FIG. 23, the attenuation shape of the notch filter for attenuating the 6th-order component and the notch filter for attenuating the 18th-order component are not changed, but the present invention is not limited to this, and can be changed as necessary. Of course. The example of FIG. 23 is an example aiming at attenuation to the 9th-order component with the skirt spread. In other words, it is possible to aim at attenuation not only to the adjacent order but also to a distant order. It is possible to attenuate the 9th-order component more greatly by making both the 6th-order and 12th-order notch filters spread out. However, since the 6th-order is close to the crossing frequency, the phase margin decreases. is necessary. Therefore, as in the example of FIG. 23, the width of the attenuation shape of the notch filter close to the crossing frequency is narrowed (the skirt is narrowed), and the width of the attenuation shape of the far notch filter is widened (the shape of the hem is widened) To achieve the desired effect. The complementary sensitivity function in this case is expressed as shown in FIG. Compared to the example of FIG. 22, it can be seen that the final attenuation effect is increased around the 12th-order component.

  Although the embodiments according to the present invention have been described above, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  For example, as shown in FIG. 25, a structure in which the motor drive unit 220 is integrated with the motor substrate 204 may be employed. According to this structure, the influence of the noise of the Hall element 202 is reduced, and in the case of a multi-control device in which the control device 230 can drive a plurality of motors 200, the motor can be reduced by reducing the cost by integrating motors and using a multi-control IC. A reduction in control cost per unit can be expected. Further, for example, as shown in FIG. 26, the motor drive unit 220 and the control unit 231 (control device 230) may be integrated with the motor board 204. According to this structure, handling of the motor 200 is facilitated, and convenience is improved. Further, as shown in FIG. 27, the motor drive unit 220 and the control device 230 may be integrated into the motor substrate 204 as a one-chip IC 250. Cost reduction can be expected by using one chip. When the motor output is small, the FET 201 shown in FIGS. 25 to 27 can be reduced in cost by being integrated with an IC that performs the function of the motor driving unit 220.

  Further, for example, as shown in FIG. 28, outside the control loop (outside of the control unit 231), a frequency component corresponding to a predetermined multiple frequency of the rotation speed of the motor 200 (with a specific frequency described in each of the above embodiments). A form in which a filter 252 for reducing (component) is provided may be used. The pseudo encoder signal generated from the Hall element 202 is related to the number of poles of the motor magnet due to the positional variation of the Hall element 202 and the magnet, the relative positional deviation between the Hall elements 202, the sensing point variation of the Hall element 202 itself, and the like. Signal fluctuations occur. Further, since the amplitude varies depending on the motor 200, the amplitude differs greatly. Therefore, even if the motor shaft rotates with high accuracy, a noise component is added to the detected speed signal, so it is difficult to use this information for feature amount detection. Therefore, by attenuating the above-mentioned specific frequency component of the speed information and rotational position information from the pseudo encoder outside the control loop with the filter setting constraint condition, the noise component generated at a predetermined multiple frequency of the motor rotation number is attenuated. No speed information and rotational position information can be obtained. The speed information and the rotational position information after the filter processing by the filter 252 (filter processing performed outside the control loop) is output to the outside of the control loop as sensing information. For example, as shown in FIG. 29, various processes (arithmetic processes for calculating feature amounts, etc.) according to the application are applied to the speed information and the rotational position information after the filter processing by the filter 252 is performed. And a processing / storing unit 253 for recording the result (may be recorded including information on the progress in progress) may be further provided. In the example of FIG. 29, the processing / storing unit 253 detects a mechanical load variation or a change in position / velocity behavior of a counterpart mechanical mechanism driven by the motor 200 as a feature amount, determines a defect, and the like, and determines a higher-level CPU (external To the target signal generator 240).

  The program executed by the control device 230 according to the above-described embodiment is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk), It may be configured to be recorded on a computer-readable recording medium such as a USB (Universal Serial Bus), or provided or distributed via a network such as the Internet. Various programs may be provided by being incorporated in advance in a ROM or the like.

100 Image forming apparatus 200 Motor 201 FET
202 Hall element 204 Motor board 210 Motor drive device 220 Motor drive unit 221 Power supply unit 222 Rotation position detection unit 230 Control device 231 Control unit 232 Motor position / speed calculation unit 233 Target position / speed calculation unit 234 Position / speed tracking control unit 235 Control gain setting unit 236 PWM signal generation unit 240 Target signal generation unit 252 Filter 253 Processing / saving unit

JP2015-19563 A

Claims (10)

A rotational position detection unit that converts a magnetic pole phase signal representing a magnetic pole phase of the motor, represents a rotation amount and a rotational direction of the output shaft of the motor, and outputs a rotational position detection signal with high resolution to the magnetic pole phase signal; A control device for controlling a motor driving unit provided,
Based on the rotation position detection signal and the target signal, the motor drive unit includes a control unit that controls power to be supplied to the motor,
The controller is
A control gain setting unit that sets a control gain so that the response of a specific frequency is reduced according to the number of poles representing the number of magnetic poles of the motor and the number of rotations of the motor;
Control device. The specific frequency is a frequency that is an integral multiple of p / 2 × N / 60, where p is the number of poles of the motor and N is the target rotational speed of the motor.
The control device according to claim 1. The control gain setting unit sets the control gain so that the responsiveness of the specific frequency included in a frequency band equal to or lower than a cross frequency of a loop transfer function representing a relationship between an input to the control unit and an output is not reduced. To
The control device according to claim 1 or 2. The rotation speed of the motor is a target rotation speed of the motor based on the target signal.
The control device according to any one of claims 1 to 3. The rotational speed of the motor is the actual rotational speed of the motor.
The control device according to any one of claims 1 to 3. The control gain setting unit performs a process of attenuating a component of the specific frequency with respect to motor control information for making a control deviation based on the target signal and the rotational position detection signal zero.
The control apparatus as described in any one of Claims 1 thru | or 4. The motor control information is information representing an output command value of the motor.
The control device according to claim 6. A motor drive device comprising: a motor drive unit that supplies power to the motor; and a control device that controls the motor drive unit,
The motor drive unit is
A rotational position detector that converts a magnetic pole phase signal representing a magnetic pole phase of the motor, represents a rotation amount and a rotational direction of the output shaft of the motor, and outputs a rotational position detection signal with high resolution to the magnetic pole phase signal; ,
A power supply unit for supplying power to the motor,
The control device includes:
Based on the rotation position detection signal and the target signal, the motor drive unit includes a control unit that controls power to be supplied to the motor,
The controller is
A control gain setting unit that sets a control gain so that the responsiveness of a specific frequency is lowered according to the number of poles of the motor and the number of rotations of the motor;
Motor drive device. A conveying member for conveying the sheet;
A motor for driving the conveying member;
A motor drive for supplying power to the motor;
A control device for controlling the motor drive unit, and a sheet conveying device comprising:
The motor drive unit is
A rotational position detector that converts a magnetic pole phase signal representing a magnetic pole phase of the motor, represents a rotation amount and a rotational direction of the output shaft of the motor, and outputs a rotational position detection signal with high resolution to the magnetic pole phase signal; ,
A power supply unit for supplying power to the motor,
The control device includes:
Based on the rotation position detection signal and the target signal, the motor drive unit includes a control unit that controls power to be supplied to the motor,
The controller is
A control gain setting unit that sets a control gain so that the responsiveness of a specific frequency is lowered according to the number of poles of the motor and the number of rotations of the motor;
Sheet conveying device. An image forming apparatus comprising: the sheet conveying apparatus according to claim 9; and an image forming unit that forms an image on the sheet.

Images