JP5262105B2 - Motor driving apparatus, image reading apparatus, image forming apparatus, and motor driving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor driver that does not cause rotor operation to be unstable when stopping the drive of a motor once and resuming the drive, an image reading apparatus, an image forming apparatus, and a motor driving method. <P>SOLUTION: The motor driver has a plurality of excitation modes, is capable of shifting from one excitation mode to another excitation mode, and drives a stepping motor having a rotor mounted on a rotating shaft thereof. In this driver, a motor control section 103 controls the rotor so as to move it to a position corresponding to the excitation mode, drives the stepping motor. When stopping the stepping motor, the motor control section also stops the rotor at a position where the rotor moves in common after the stop of the rotor is instructed and in a plurality of excitation modes. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a motor drive device, an image reading device, an image forming apparatus, and a motor drive method, and more particularly to motor stop control.

  When an image reading device such as a scanner drives an image sensor unit to read a document, it is generally known that a stepping motor is used as the driving device. Such a stepping motor can control the rotation speed by a plurality of excitation modes. However, when the rotation of the stepping motor is changed from one excitation mode to another excitation mode, if the position where the two excitation modes are stopped does not match, the position of the rotor becomes indefinite and the read image is shifted. There was a problem that there was a case.

  As a solution to such a problem, a motor drive device that smoothly transitions between two excitation modes during driving is disclosed (see Patent Document 1). In such a motor drive device, when a transition is made from one excitation mode to another excitation mode, it is determined that the rotor has moved to a common position in the two excitation modes, thereby making the rotor position indefinite. Without transitioning to the next excitation mode.

JP 2004-140890 A

  However, in the technique described in Patent Document 1, when the stepping motor is temporarily stopped and the operation is started in an excitation mode different from the excitation mode when the stepping motor is stopped, the rotor position corresponds to the excitation mode in which the operation starts. If the position does not stop, the rotor operation becomes indefinite, and the problem that the read image is displaced cannot be solved.

  The present invention has been made in view of the above, and is a motor driving device, an image reading device, an image forming apparatus, and a motor driving method in which the operation of the rotor does not become unstable when the driving of the motor is temporarily stopped and operated again. The purpose is to provide.

In order to solve the above-described problems and achieve the object, the invention according to claim 1 includes a plurality of excitation modes, is capable of transitioning from one excitation mode to another, and is fixed to the outer periphery. In a motor driving apparatus that drives a stepping motor having a stator and a rotor attached to a rotating shaft , a plurality of control patterns that are pulse signals are converted into currents, respectively, and the stator corresponding to the control patterns is excited. and a motor driver for driving the stepping motor by, by one of a plurality of said control pattern for moving the rotor to a position corresponding to the plurality of excitation modes and outputs to the motor driver, the stepping motor after the motor control means for controlling, stopping of the rotor is indicated, the plurality of excitation model And stop control means for the rotor to common controls to stop the rotor when the motor control means the control pattern for moving the rotor to a 2-phase position is a position where the movement is used in de, the rotor Stop excitation mode storage means for storing the excitation mode corresponding to the stop position, and each time the motor control means controls to move the rotor to the two-phase position, the motor control means A position flag indicating that the rotor has been controlled to move is sent out, and when the rotor is controlled to stop, a stop command flag that instructs the rotor to stop is sent out and stored in the stop excitation mode storage means A position indicating that when the rotor is controlled to move to a position corresponding to the excitation mode, the rotor is controlled to move to the position. The stop control means determines that the position where the position flag is transmitted is the stop position of the rotor and stops the rotor at the determined stop position after the stop instruction flag is transmitted. It is characterized by controlling .

The invention according to claim 2, in the motor driving apparatus according to claim 1, wherein the stop excitation mode storage means, together with the excitation mode, stores the rotational direction indicating a direction of rotation of said rotor, said motor When the rotor is controlled to move to a position corresponding to the excitation mode stored in the stop excitation mode storage means according to the rotation direction stored in the stop excitation mode storage means, the control means A position flag indicating that the rotor is controlled to move to a position is transmitted.

The invention according to claim 3 is the motor drive device according to claim 1 , further comprising stop position storage means for storing a position where the rotor stops, wherein the motor control means is the stop position storage means. When the rotor is controlled to move to the position stored in the position, a position flag indicating that the rotor is controlled to move to the position is sent.

The invention according to claim 4 is the motor driving apparatus according to claim 1, further comprising a motor control information storing means for storing a transition order of the excitation mode for controlling the rotation of said rotor, said motor The control means that when the rotor is controlled to move to a position corresponding to the next excitation mode stored in the motor control information storage means, the rotor is controlled to move to that position. The position flag which shows is sent out.

According to a fifth aspect of the present invention, in the motor drive device according to the fourth aspect , the motor control information storage means stores a rotation direction indicating a rotation direction of the rotor in association with the excitation mode, and The motor control means controls the rotor to move to a position corresponding to the next excitation mode stored in the motor control information storage means according to the rotation direction stored in the motor control information storage means. If it is, a position flag indicating that the rotor has been controlled to move to the position is sent out.

According to a sixth aspect of the present invention, in the motor drive device according to the first aspect, an address corresponding to a position where the rotor moves and a control for driving the stepping motor by moving the rotor to the position. Control pattern storage means for storing the pattern in association with each other, and address acquisition means for acquiring an address corresponding to a position where the rotor moves next time by adding an offset value corresponding to the excitation mode to the address. Control pattern acquisition means for acquiring the control pattern corresponding to the address acquired by the address acquisition means from the control pattern storage means, and the motor control means is acquired by the control pattern acquisition means Sending the control pattern to the motor driver More, by controlling so that the rotor is moved to the position, characterized by.

According to a seventh aspect of the present invention, in the motor drive device according to the sixth aspect , the control pattern storage means stores an addition / subtraction address value associated with the address, and the address acquisition means stores the previous address. In addition, the address corresponding to the position where the rotor moves next time is obtained by adding the addition / subtraction address value stored corresponding to the address.

According to an eighth aspect of the present invention, in the motor drive device according to the fifth aspect , the motor control information storage means associates the number of repetitions, which is the number of times the rotor stops at the same position, with the excitation mode. And the motor control means sends the control pattern acquired by the control pattern acquisition means in accordance with the number of repetitions stored in the motor control information storage means, thereby moving the rotor. Is controlled.

The invention according to claim 9 is the motor drive device according to claim 6 , wherein the control pattern storage means is stored in a readable / writable storage section.

According to a tenth aspect of the present invention, in the image reading apparatus, the original is read by driving the image reading unit with the stepping motor controlled by the motor driving device according to the first aspect. .

According to an eleventh aspect of the present invention, an image forming apparatus includes the image reading apparatus according to the tenth aspect, and performs image processing on image information read by the image reading apparatus.

According to a twelfth aspect of the present invention, there is provided a plurality of excitation modes, the transition from one excitation mode to another excitation mode is possible, and a stator fixed to the outer periphery and a rotor attached to the rotating shaft. In a motor driving method executed by a motor driving device that drives a stepping motor having a plurality of control patterns that are pulse signals, each of which is converted into current, and the stepping motor is excited by exciting the stator corresponding to the control pattern. to the motor driver for driving, by outputting one of a plurality of said control pattern for moving the rotor to a position corresponding to the plurality of excitation modes, and a motor control step of controlling the stepping motor, the rotor After the stop is instructed, the rotor is commonly used in the plurality of excitation modes. Storing a stop control step of controlling so as to stop the rotor when the control pattern for moving the rotor to a 2-phase position is a position where the movement is used, the excitation mode corresponding to the position where the rotor stops seen including a stop excitation mode storage step, the of, in the motor control step, each time the control to move the rotor to the two-phase position, indicating that the rotor in the two-phase position is controlled to move When a position flag is sent and the rotor is controlled to stop, a stop command flag is sent to stop the rotor, and the rotor is moved to a position corresponding to the excitation mode stored in the stop excitation mode storage step. When controlled to move, a position flag indicating that the rotor has been controlled to move to the position is sent out, and the stop control is performed. In step, after the stop instruction flag is sent, the position where the position flag is sent is determined that the stop position of the rotor, stopping controlling said rotor at the determined said stop position, characterized by .

  According to the present invention, when the stepping motor is stopped, the rotor stops at the two-phase position where the rotor moves in common in a plurality of excitation modes. As a result, the operation of the rotor does not become unstable.

  Exemplary embodiments of a motor driving apparatus, an image reading apparatus, an image forming apparatus, and a motor driving method according to the present invention will be explained below in detail with reference to the accompanying drawings. The present invention is not limited to these embodiments.

(First embodiment)
A first embodiment will be described with reference to the accompanying drawings. In the motor drive device according to the first embodiment, when stopping the stepping motor, the rotor to be driven is driven in any one of a plurality of excitation modes of the stepping motor. Control is performed so that the rotor stops at the two-phase position where the rotor moves in common in a plurality of excitation modes. In the present embodiment, a case where the motor drive device is applied to drive the image reading unit of the image reading device will be described.

  First, a configuration example of a motor driving device to which the present invention is applied will be described. FIG. 1 is a block diagram illustrating the configuration of the motor drive device according to the first embodiment. The motor driving apparatus 100 according to the present embodiment includes a stepping motor 101, a motor driver 102, a motor control unit 103, a control pattern information acquisition unit 104, a setting information acquisition unit 105, and a motor control information generation unit 106. The control pattern information storage unit 110 and the motor control information storage unit 120 are provided.

  The stepping motor 101 is composed of an electromagnet (stator) fixed to the outer periphery and a magnet (rotor) attached to a rotating shaft. The rotating shaft rotates by passing current through the stator, magnetizing the stator and attracting the rotor. The motor is driven. The motor driver 102 converts a control pattern (pulse signal) sequentially sent from a motor control unit 103 described later into a current and sends it to the stepping motor 101, whereby the stator corresponding to the sent control pattern is magnetized. The stepping motor 101 is driven by attracting the rotor.

  The motor control unit 103 controls the driving of the stepping motor 101 by sending a control pattern to the motor driver 102. The motor control unit 103 may be configured by either a control circuit or a program operating on the CPU. When configured as a control circuit, the stepping motor 101 is controlled not by the CPU but by the control circuit, so that the load on the CPU in the apparatus can be reduced.

  The motor control unit 103 further includes a control pattern generation unit 1031 and a stop position determination unit 1032. The control pattern generation unit 1031 constitutes motor control means in the present invention. The control pattern generation unit 1031 and the stop position determination unit 1032 constitute stop control means in the present invention.

  The control pattern generation unit 1031 is for controlling the stepping motor 101 from the control pattern stored in the control pattern information storage unit 110, which will be described later, according to the transition order of the motor control information stored in the motor control information storage unit 120. A control pattern (pulse signal) is generated and sent to the motor driver 102. This motor control information is information indicating how to control and drive the stepping motor 101 in order to operate the image reading unit generated from the size of the document for reading an image, information input from the operation unit, and the like. These are generated by the motor control information generation unit 106, which will be described later, at the time of document reading and stored in the motor control information storage unit 120.

  When the control pattern generation unit 1031 determines that the control pattern sent to the motor driver 102 is a control pattern for moving the rotor to the stator position corresponding to the two-phase excitation mode, the control pattern generation unit 1031 sets the two-phase position flag to the stop position. The data is sent to the determination unit 1032. Here, the excitation mode is a type of driving method when driving the stepping motor. Note that the stepping motor according to the present embodiment can be controlled in three excitation modes: a two-phase excitation mode, a 1-2 phase excitation mode, and a W1-2 phase excitation mode. Next, when the stepping motor 101 is driven in the respective excitation modes of the two-phase excitation mode, the 1-2 phase excitation mode, and the W1-2 phase excitation mode, the stator attracts the rotor attached to the rotating shaft by being magnetized. The position of will be described.

  FIG. 2 is an explanatory diagram showing an example of the position of the stator in the stepping motor and the position where the rotor moves in each excitation mode. FIG. 3 is an explanatory diagram showing an address corresponding to the position of the stator and an address to which the rotor is attracted for each excitation mode. FIG. 2 shows the position (0) to position (15) of the stator obtained by dividing the stepping motor vertically above the position (0) and dividing 360 ° into 16 equal parts. The stators at positions (0) to (15) are excited, and the motor is driven to rotate by attracting the rotor. As for the rotation direction of the motor, the A → A ′ direction is forward rotation, and the B → B ′ direction is counter rotation. In FIG. 3, as shown in FIG. 2, when the stepping motor is driven in each excitation mode, a list of addresses corresponding to positions where the rotor moves for each excitation mode is listed.

  As described above, the stepping motor 101 of the present embodiment corresponds to the three excitation modes. In the two-phase excitation mode, the rotor is attracted to the stator at positions (0), (4), (8), and (12), and the motor rotates. In the 1-2 phase excitation mode, the rotor is attracted to the stator at positions (0), (2), (4), (6), (8), (10), (12), and (14) to Rotate. In the W1-2 phase excitation mode, the rotor is sequentially attracted to all of the stators at the positions (0) to (15), and the motor rotates. Therefore, the positions (0), (4), (8), (12), that is, the positions corresponding to the two-phase excitation mode are positions common to the three excitation modes. That is, when the rotor stops at these positions, the next operation start position is a position corresponding to all excitation modes that are not indefinite, regardless of which of the three excitation modes operates next. Therefore, once the motor is stopped and then restarted, the rotor starts moving from the position corresponding to the re-excited excitation mode. Therefore, the amount of movement of the rotor is constant and the read image is displaced. Absent. When the rotor is stopped, it is possible to perform high-quality reading with no image shift by stopping at a position corresponding to the two-phase excitation mode. The excitation mode is not limited to the three excitation modes described here, and the position is not limited to the position of 16 equal parts.

  In addition, the control pattern generation unit 1031 sends a stop command flag to the stop position determination unit 1032 when the image reading unit controls to stop the stepping motor 101 in accordance with the motor control information such as at the end of image reading. In addition, when receiving a stop position flag from a stop position determination unit 1032 described later, the control pattern generation unit 1031 sends a control pattern for stopping the rotor to the motor driver 102. As a result, the rotor is stopped at the position corresponding to the stop position flag.

  When the stop position determination unit 1032 receives the stop command flag from the control pattern generation unit 1031 and then receives the position flag, the stop position determination unit 1032 determines the position corresponding to the received position flag as the stop position, and sets the stop position flag to the control pattern. The data is sent to the generation unit 1031.

  The control pattern information storage unit 110 stores an address corresponding to each position of the stator and a control pattern for exciting the stator corresponding to the address. FIG. 4 is an explanatory diagram illustrating an example of a data configuration of the control pattern information storage unit. The control pattern information storage unit 110 stores an address corresponding to each of the stator positions (0) to (15) and a control pattern for exciting the stator corresponding to the address in association with each other. The control pattern is stored when the apparatus is manufactured. The control pattern information storage unit 110 is configured by a readable / writable memory (RAM).

  The control pattern information acquisition unit 104 acquires a control pattern, and stores the acquired control pattern in the control pattern information storage unit 110 in association with an address. The acquired control pattern is a control pattern of the motor driver 102 corresponding to the stepping motor 101 mounted on the motor driving device. The control pattern information acquisition unit 104 stores the corresponding control pattern in the control pattern information storage unit 110 when the stepping motor 101 mounted on the motor driving device is determined. Thereby, even when the specification of the stepping motor 101 is not determined, the design of the motor control unit 103 can be advanced, and a corresponding control pattern can be stored in the motor control unit 103 after the design is completed. Moreover, even when the motor drive device is equipped with stepping motors 101 of various specifications, it is not necessary to provide a conversion circuit corresponding to each stepping motor, and a motor drive device corresponding to each specification can be manufactured simply by rewriting the control pattern. can do.

  The setting information acquisition unit 105 acquires information necessary for generating motor control information for the stepping motor 101. For example, the motor control information including the rotation direction of the stepping motor 101, the excitation mode, the number of repetitions, and the drive time is determined by setting the paper size and image quality acquired by the operation unit, single-sided / double-sided printing, and the like.

  The motor control information generation unit 106 generates motor control information of the stepping motor 101 for reading an image from a document from the setting information acquired by the setting information acquisition unit 105, and stores it in the motor control information storage unit 120.

  The motor control information storage unit 120 stores the motor control information generated by the motor control information generation unit 106. FIG. 5 is an explanatory diagram illustrating an example of a data configuration of the motor control information storage unit. The motor control information storage unit 120 stores the motor rotation direction, the excitation mode, the number of repetitions, and the number of pulses in association with each other in the order of motor operation. Here, values such as “forward rotation”, “counter rotation” or “stop” shown in FIG. 2 are stored in the rotation direction of the motor. In the excitation mode, one of the excitation modes supported by the stepping motor is stored. The number of repetitions stores the number of times the control pattern information storage unit 110 is referred to. The number of pulses stores the number of times that a pulse signal corresponding to a control pattern defined by the rotation direction, excitation mode, and number of repetitions is sent to the stepping motor 101. With this motor control information, the driving of a series of motors in the image reading process can be controlled.

  FIG. 6 is an explanatory diagram in which an example of the motor control information is graphed by the rotational speed of the rotor and the elapsed time. In order to execute driving of the motor as shown in FIG. 6, motor control information is stored in the motor control information storage unit 120 in the format shown in FIG. At S0, the initial value of the position counter is set and used as a reference for the motor drive position. In the acceleration / deceleration state (S1, S3, S5, S7), the motor is operated with reference to values set in an acceleration / deceleration time table (RAM) (not shown).

  Furthermore, in the present embodiment, values that each item of motor control information can take will be described. FIG. 7 is an explanatory diagram illustrating an example of values that can be taken by the rotation direction, the excitation mode, and the number of repetitions, which are motor control information. As shown in FIG. 7, the rotation direction is “forward rotation”, “counter rotation”, the excitation mode is “W1-2 phase”, “1-2 phase”, “2 phase”, and the number of repetitions is “1”. The value can be “times”, “2 times”, “3 times”, or “4 times”.

  Next, motor drive control processing by the motor drive device configured as described above will be described. FIG. 8 is a flowchart showing a motor drive control processing procedure performed by the motor control unit. It is assumed that the number of pulses sent to the stepping motor 101 is counted in the entire series of image reading processes.

  First, the setting information acquisition unit 105 acquires setting information input from an operation unit (not shown) (step S801). The motor control information generation unit 106 generates motor control information for a series of reading processes from the setting information (step S802), and the motor control information generation unit 106 stores the generated motor control information in the motor control information storage unit 120. (Step S803).

  The control pattern generation unit 1031 acquires motor control information corresponding to the counted number of pulses from the motor control information storage unit 120 (step S804). Here, the motor control information with the counted number of pulses is the motor control information corresponding to the number of pulses counted when the motor starts operation, among the motor control information stored in the motor control information storage unit 120. Specifically, the counted number of pulses is a value of each of the rotation direction, excitation mode, and number of repetitions that matches the sum of the number of pulses in FIG. For example, if the number of pulses counted when the motor starts driving is 2550, the values of the rotation direction, excitation mode, and number of repetitions corresponding to the total number of pulses of 2550 in the motor control information shown in FIG. To get.

  The control pattern generation unit 1031 determines whether or not the acquired motor control information indicates the end of driving of the motor (step S805). If it is determined that the acquired motor control information indicates the end of driving of the motor (step S805: Yes), the process ends. When it is determined that the acquired motor control information does not indicate the end of driving of the motor (step S805: No), the control pattern generation unit 1031 determines whether or not the acquired motor control information indicates stop of driving of the motor ( Step S806). If it is determined that the acquired motor control information does not indicate that the motor has stopped driving (step S806: No), an address control process is performed (step S807). Details of the address control process will be described later.

  Next, the control pattern generation unit 1031 acquires a control pattern corresponding to the address obtained by the address control process from the control pattern information storage unit 110 (step S808). The control pattern generation unit 1031 sends the acquired control pattern to the motor driver 102 (step S809). Thereby, the stepping motor 101 is rotationally driven. Further, the control pattern generation unit 1031 determines whether or not the control pattern is a control pattern for controlling the rotor to move to the two-phase position (step S810). Specifically, the control pattern sent to the motor driver 102 is compared with the control pattern corresponding to the two-phase position, and when it matches, the control pattern controls the rotor to move to the two-phase position. to decide. If it is determined that the control pattern is such that the rotor is controlled to move to the two-phase position (step S810: Yes), a two-phase position flag is sent to the stop position determination unit 1032 (step S811). If it is determined that the control pattern does not control the rotor to move to the two-phase position (step S810: No), the process returns to step S804.

  If it is determined in step S806 that the acquired motor control data indicates that the motor is stopped (step S806: Yes), a stop command flag is sent to the stop position determination unit 1032 (step S812). A stop position determination process is performed (step S813). Details of the stop position determination process will be described later. The control pattern generation unit 1031 determines whether or not a stop position flag has been received from the stop position determination unit 1032 (step S814). If it is determined that the stop position flag has been received (step S814: Yes), a control pattern for stopping the rotor is transmitted (step S815). As a result, the rotor stops at a position corresponding to the two-phase excitation mode. Thereafter, the process returns to step S804. If it is determined that the stop position flag has not been received (step S814: No), the process returns to step S804.

  Next, address control processing will be described. FIG. 9 is a flowchart illustrating an address control processing procedure performed by the control pattern generation unit.

  First, the control pattern generation unit 1031 determines whether or not the acquired rotation direction is “forward rotation” (step S901). If it is determined that the acquired rotation direction is “forward rotation” (step S901: Yes), the sign of the offset value is set to “+” (step S902). When it is determined that the acquired rotation direction is not “forward rotation”, that is, “reverse rotation” (step S901: No), the sign of the offset value is set to “−” (step S903).

  The control pattern generation unit 1031 determines whether or not the acquired excitation mode is “two-phase” (step S904). If it is determined that the acquired excitation mode is “two-phase” (step S904: Yes), the offset value is set to “4” (step S905). When it is determined that the acquired excitation mode is not “two-phase” (step S904: No), the control pattern generation unit 1031 determines whether the acquired excitation mode is “1-2 phase” (step S906). ).

  When it is determined that the acquired excitation mode is “1-2 phase” (step S906: Yes), the offset value is set to “2” (step S907). When it is determined that the acquired excitation mode is not “1-2 phase”, that is, “W1-2 phase” (step S906: No), the offset value is set to “1” (step S908).

  The control pattern generation unit 1031 determines whether or not the number of repetitions is being performed (step S909). If it is determined that the number of repetitions is in progress (step S909: Yes), the offset value is set to “0”. For example, if the number of repetitions is 2, 3, or 4 and is in the number of repetitions, that is, if the second address is calculated with 2 repetitions, 1 In order to set the same address as the first time, the offset value is set to “0”. Thereby, since the rotor stops at the same position, the motor speed becomes 1/2 of the case where the number of repetitions is one.

  Similarly, when the number of repetitions is 3, and the second and third addresses are calculated, the offset value is set to “0” in order to obtain the same address as the first time. Thereby, since the rotor stops at the same position three times, the motor speed becomes 1/3 of the case where the number of repetitions is one. In addition, when the number of repetitions is 4, and the second, third, and fourth addresses are calculated, the offset value is set to “0” because the address is the same as the first time. As a result, the rotor stops at the same position four times, so that the motor speed is ¼ that when the number of repetitions is one.

  If it is determined in step S909 that the number of repetitions is not in progress (step S909: No), the process proceeds to step S911. The control pattern generation unit 1031 calculates the current address value by adding the offset value to the previous address value (step S911).

  FIG. 10 is an explanatory diagram illustrating an example of an address control process performed by the control pattern generation unit. As shown in FIG. 10, a case where the rotation direction is “forward rotation”, the excitation mode is “two-phase”, and the number of repetitions is “1 time” will be described. The control pattern at address “0” is acquired from the control pattern stored in the control pattern information storage unit 110 and sent to the motor driver 102, whereby the rotor is attracted to the position (0) and the motor rotates. . Next, the control pattern of the address “4” is acquired by the address “0” +4 and is sent to the motor driver 102, whereby the rotor is attracted to the position (4) and rotates. By repeating this, the motor is driven to rotate at a constant speed.

  In this way, by acquiring the control pattern by address control and sending it to the motor driver 102, the rotor is attracted to the intended position and the motor can be rotated, so the load on the CPU can be reduced. .

  As for address control, instead of adding or subtracting the offset value as described above, the next address may be calculated by bit operation to perform address control. By calculating the next address by performing bit operations on the 4-bit address, it is possible to calculate the address at higher speed.

  Next, the stop position determination process will be described. FIG. 11 is a flowchart illustrating a stop position determination processing procedure performed by the stop position determination unit.

  First, the stop position determination unit 1032 determines whether or not a stop command flag has been received (step S1101). If it is determined that the stop instruction flag has not been received (step S1101: No), the process ends. If it is determined that the stop command flag has been received (step S1101: Yes), it is determined whether a two-phase position flag has been received (step S1102). If it is determined that the two-phase position flag has been received (step S1102: Yes), a stop position flag is sent to the control pattern generation unit 1031 (step S1103). When it is determined that the two-phase position flag has not been received (step S1102: No), the process is exited. Thereby, the rotor does not stop at a position other than the position corresponding to the two-phase excitation mode.

  As described above, by determining that the two-phase position flag is received after the stop command flag is received, the position corresponding to the two-phase excitation mode in which the rotor is to be stopped can be easily determined.

  FIG. 12 is an explanatory diagram showing the relationship among the two-phase position flag, the stop command flag, and the stop position flag. As shown in FIG. 12, the two-phase position flag is sent out at a position corresponding to the two-phase excitation mode, that is, at positions (0), (4), and (8). The control pattern generation unit 1031 determines that the motor drive is stopped, and sends a stop command flag at position (5). Since the position where the two-phase position flag is transmitted after the stop command flag is transmitted is the position (8), the stop position flag is transmitted at the position (8).

  Next, the control pattern storage process will be described. FIG. 13 is a flowchart illustrating a control pattern storage processing procedure performed by the control pattern information acquisition unit.

  The control pattern information acquisition unit 104 acquires a control pattern corresponding to the stepping motor 101 mounted on the motor drive device (step S1301). The control pattern information acquisition unit 104 stores the acquired control pattern in association with the address in the control pattern information storage unit 110 (step S1302).

  Thus, by freely rewriting and storing the control pattern, the control pattern corresponding to the stepping motor mounted on the motor drive device is stored, and the stepping motor is controlled using the control pattern corresponding to the stepping motor. Therefore, it is not necessary to provide a conversion circuit for dealing with stepping motors having different specifications, and the configuration for controlling the motor can be simplified.

  In addition, a motor control unit corresponding to a stepping motor can also be configured by storing a control pattern corresponding to the specification for a motor drive device equipped with stepping motors having different specifications.

  In this embodiment, the motor driving device mounted on the image reading device has been described. However, the device on which the motor driving device is mounted is not limited to the image reading device, and is a device driven by a stepping motor. Can be applied if present.

  In addition, an image reading apparatus equipped with the motor drive device according to the present embodiment may be installed in a multifunction peripheral that is an image forming apparatus. FIG. 14 is an explanatory diagram illustrating a hardware configuration of the multifunction machine. As shown in the figure, the multifunction machine 1 has a configuration in which a controller 10 and an engine unit (Engine) 60 are connected by a PCI (Peripheral Component Interconnect) bus. The controller 10 is a controller that controls the entire MFP 1 and controls drawing, communication, and input from the operation unit 20. The engine unit 60 is a printer engine that can be connected to a PCI bus, and is, for example, a monochrome plotter, a one-drum color plotter, a four-drum color plotter, a scanner, or a fax unit. The engine unit 60 includes an image processing part such as error diffusion and gamma conversion in addition to a so-called engine part such as a plotter.

  The controller 10 includes a CPU 11, a north bridge (NB) 13, a system memory (MEM-P) 12, a south bridge (SB) 14, a local memory (MEM-C) 17, and an ASIC (Application Specific Integrated Circuit). 16 and a hard disk drive (HDD) 18, and the north bridge (NB) 13 and the ASIC 16 are connected by an AGP (Accelerated Graphics Port) bus 15. The MEM-P 12 further includes a ROM (Read Only Memory) 12a and a RAM (Random Access Memory) 12b.

  The CPU 11 performs overall control of the multifunction machine 1 and includes a chip set including the NB 13, the MEM-P 12, and the SB 14, and is connected to other devices via the chip set.

  The NB 13 is a bridge for connecting the CPU 11 to the MEM-P 12, SB 14, and the AGP bus 15, and includes a memory controller that controls reading / writing with respect to the MEM-P 12, a PCI master, and an AGP target.

  The MEM-P 12 is a system memory used as a memory for storing programs and data, a memory for developing programs and data, a memory for drawing a printer, and the like, and includes a ROM 12a and a RAM 12b. The ROM 12a is a read-only memory used as a program / data storage memory, and the RAM 12b is a writable / readable memory used as a program / data development memory, a printer drawing memory, or the like.

  The SB 14 is a bridge for connecting the NB 13 to a PCI device and peripheral devices. The SB 14 is connected to the NB 13 via a PCI bus, and a network interface (I / F) unit and the like are also connected to the PCI bus.

  The ASIC 16 is an IC (Integrated Circuit) for image processing having hardware elements for image processing, and has a role of a bridge for connecting the AGP bus 15, the PCI bus, the HDD 18, and the MEM-C 17. The ASIC 16 includes a PCI target and an AGP master, an arbiter (ARB) that forms the core of the ASIC 16, a memory controller that controls the MEM-C 17, a plurality of DMACs (Direct Memory) that perform rotation of image data by hardware logic and the like. Access Controller) and a PCI unit that performs data transfer between the engine unit 60 via the PCI bus. An FCU (Fax Control Unit) 30, a USB (Universal Serial Bus) 40, and an IEEE 1394 (the Institute of Electrical and Electronics Engineers 1394) interface 50 are connected to the ASIC 16 via a PCI bus.

  The MEM-C 17 is a local memory used as an image buffer for copying and a code buffer, and an HDD (Hard Disk Drive) 18 is a storage for storing image data, programs, font data, and forms. It is.

  The AGP bus 15 is a bus interface for a graphics accelerator card proposed for speeding up graphics processing. The AGP bus 15 speeds up the graphics accelerator card by directly accessing the MEM-P 12 with high throughput. It is.

  Note that the motor drive control program executed by the motor drive device of the present embodiment is provided by being incorporated in advance in a ROM or the like.

  The motor drive control program executed by the motor drive apparatus of the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, flexible disk (FD), CD-R, DVD (Digital Versatile Disk). For example, the program may be recorded on a computer-readable recording medium.

  Furthermore, the motor drive control program executed by the motor drive device of the present embodiment may be configured to be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network. . Further, the motor drive control program executed by the motor drive device of this embodiment may be provided or distributed via a network such as the Internet.

  The motor drive control program executed by the motor drive device of the present embodiment has a module configuration including the above-described units (motor control unit, control pattern acquisition unit, setting information acquisition unit, motor control data generation unit, etc.). As actual hardware, the CPU (processor) reads the motor drive control program from the ROM and executes it to load each of the above units onto the main storage device. The motor control unit, control pattern acquisition unit, and setting information acquisition And a motor control data generator are generated on the main memory.

  Note that the motor control unit may be configured by hardware such as a control circuit instead of the configuration as software.

  The present invention is not limited to the above-described embodiment. As other embodiments, a second embodiment and a third embodiment will be described.

(Second Embodiment)
A second embodiment will be described with reference to the accompanying drawings. The motor drive device according to the second embodiment controls the rotor to stop at a position corresponding to a preset excitation mode when stopping the stepping motor.

  Regarding the configuration example of the motor drive device to which the present invention is applied, the parts different from the first embodiment will be described. The other parts are the same as those in the first embodiment, so the description is omitted with reference to the above description. FIG. 15 is a block diagram illustrating a configuration of a motor driving device according to the second embodiment.

  The motor driving apparatus 200 according to the present embodiment includes a stepping motor 101, a motor driver 102, a motor control unit 203, a control pattern information acquisition unit 104, a setting information acquisition unit 105, and a motor control information generation unit 106. The control pattern information storage unit 110, the motor control information storage unit 120, and the address control information storage unit 230 are provided.

  Here, the stepping motor 101, the motor driver 102, the control pattern information acquisition unit 104, the setting information acquisition unit 105, the motor control information generation unit 106, the control pattern information storage unit 110, and the motor control information storage unit 120. Since the configuration and function are the same as those in the first embodiment, description thereof will be omitted.

  The address control information storage unit 230 stores control information used when controlling addresses. FIG. 16 is an explanatory diagram showing an example of the data configuration of the address control information storage unit and possible values. As shown in FIG. 16, the address control information storage unit 230 is provided with values for the next address designation method, the add / subtract address value, the stop excitation mode, the stop position, and the stop direction.

  For example, when “constant” is set in the next address designating method, as described in the first embodiment, a constant address is added according to the excitation mode, and the next address is set. On the other hand, when “designation” is set, the next address is set by adding / subtracting the addition / subtraction address value set in the addition / subtraction address value to / from the previous address. Details will be described later.

  When “two-phase” is set in the stop excitation mode, the rotor is stopped at a position corresponding to the two-phase excitation mode, as in the case described in the first embodiment. When “5” is set as the stop position, the rotor is stopped at the position (5). When “forward rotation” is set in the stop direction, when the excitation mode is set in the stop excitation mode, the rotation is rotated forward and stops at a position corresponding to the set excitation mode. Thus, in this embodiment, the rotor is not only stopped at the position corresponding to the two-phase excitation mode as in the first embodiment, but also at the set position or the position corresponding to the set excitation mode. Can be stopped.

  The motor control unit 203 further includes a control pattern generation unit 2031 and a stop position determination unit 1032. Since the configuration and function of the stop position determination unit 1032 are the same as those in the first embodiment, description thereof is omitted. In addition to the functions and configurations described in the first embodiment, the control pattern generation unit 2031 sends a control pattern corresponding to the stop excitation mode and stop position stored in the address control information storage unit 230 to the motor driver 102. When this happens, the position flag is sent to the stop position determination unit 1023. As a result, the stop position determination unit 1023 determines the stop position using the received position flag as in the first embodiment.

  Next, motor drive control processing by the motor control unit configured as described above will be described. FIG. 17 is a flowchart illustrating a motor drive control processing procedure performed by the motor control unit. Since the procedure of the motor drive control process according to the present embodiment is almost the same as the flowchart shown in FIG. 8, only different parts will be described. Steps S1701 to S1703, steps S1705 to S1710, and steps S1713 to S1716 refer to the description in FIG.

  In step S1704, the control pattern generation unit 2031 acquires the address information stored in the address control information storage unit 230 (step S1704). For example, when “specified” is stored in the next address in the address control information, a plurality of numerical values are stored as add / subtract address values corresponding to each address, “two-phase” in the stop excitation mode, and “forward rotation” in the stop direction, Get each value. Each acquired value is used in an address control process and a stop position determination process described later.

  In step S1711, the control pattern generation unit 2031 determines whether or not the control pattern is a control pattern for controlling the rotor to move to a position corresponding to the stop excitation mode (step S1711). If it is determined that the control pattern is to control the rotor to move to a position corresponding to the stop excitation mode (step S1711: Yes), a position flag is sent to the stop position determination unit 1032 (step S1712). If it is determined that the control pattern does not control to move the rotor to the position corresponding to the stop excitation mode (step S1711: No), the process returns to step S1705.

  In this way, when the rotor is controlled to move to a position corresponding to the stop excitation mode, the rotor can be stopped at a position corresponding to the excitation mode intended by the user by sending the position flag.

  In step S1711, whether or not the control pattern is controlled so that the rotor moves to the position set as the stop position in the address control information, for example, the position (5), instead of the position corresponding to the stop excitation mode. It may be judged. Thereby, the rotor of the stop position which a user intends can be stopped.

  Next, address control processing will be described. FIG. 18 is a flowchart illustrating an address control processing procedure performed by the control pattern generation unit.

  First, the control pattern generation unit 2031 determines whether or not the acquired rotation direction is “forward rotation” (step S1801). When it is determined that the acquired rotation direction is “forward rotation” (step S1801: Yes), the sign of the addition / subtraction address value is set to “+” (step S1802). When it is determined that the acquired rotation direction is not “forward rotation”, that is, “reverse rotation” (step S1801: No), the sign of the addition / subtraction address value is set to “−” (step S1803).

  The control pattern generation unit 2031 acquires the addition / subtraction address value corresponding to the previous address value from the address control information storage unit 230 (step S1804). The control pattern generation unit 2031 determines whether the number of repetitions is in progress (step S1805). If it is determined that the number of repetitions is in progress (step S1805: YES), the add / subtract address value is set to “0” (step S1806). If it is determined that the number of repetitions is not in progress (step S1805: NO), the process proceeds to step S1807. The control pattern generation unit 2031 calculates the current address value by adding the addition / subtraction address value to the previous address value (step S1807).

  In this way, the motor can be driven by controlling the position where the rotor moves according to the adjustment address value set by the user, instead of adjusting the offset value determined in accordance with the excitation mode. The motor drive can be controlled.

  FIG. 19 is an explanatory diagram showing an example of address control. The flow of the address control process when the add / subtract address value as shown in FIG. 19 is stored will be described with reference to FIG. In this example, the rotation direction is “forward rotation”, the “excitation mode” is “two-phase”, and the number of repetitions is “one”.

  First, the control pattern generation unit 2031 determines that the acquired rotation direction is “forward rotation” (step S1801: Yes), and sets the sign of the addition / subtraction address value to “+” (step S1802). When the previous address value is “0”, the control pattern generation unit 2031 obtains the addition / subtraction address value “2” corresponding to the previous address “0” from the addition / subtraction address value (step S1804).

  Since the number of repetitions is “1”, the control pattern generation unit 2031 determines that the number of repetitions is not in progress (step S1805: No), and proceeds to step S1807. The control pattern generation unit 2031 calculates the current address “2” by adding the additional address value “2” to the previous address “0” (step S1807). Thus, the control pattern “table 2” corresponding to the address “2” is acquired from the control pattern information storage unit 110, and the rotor is controlled to move to the position (2). Similarly, the next address is calculated by adding the add / subtract address value corresponding to the address value to the previous address. Thereafter, address control is performed in the same manner.

  Next, stop position determination processing in the present embodiment will be described. Since the stop position determination process is substantially the same as that of the first embodiment, only different points will be described here with reference to FIG. 11 described above and the description thereof.

  Instead of sending a position flag when the rotor is positioned at a position corresponding to the two-phase excitation mode in the first embodiment, in this embodiment, the excitation mode stored as the stop excitation mode is used. When the rotor moves to the corresponding position, a position flag is sent out. When the position flag is received after receiving the stop command flag, the stop position determination unit 1032 sets the position corresponding to the position flag as the stop position, and sends the stop position flag to the control pattern generation unit 2031.

  Thereby, the rotor can be stopped at a position corresponding to an arbitrary excitation mode, and the stop position of the rotor does not become unstable.

  FIG. 20 is an explanatory diagram showing an example of the relationship between the current operation excitation mode and the stop excitation mode. As shown in FIG. 20, since the rotation direction is “forward rotation” and the operation excitation mode is “W1-2 phase”, the positions where the rotor moves are positions (0) to (15). Further, since the stop excitation mode is “two-phase”, a position flag is transmitted at positions (0), (4), (8), and (12). As shown in FIG. 20, when the stop command flag is sent at the position (9), the stop position flag is sent at the position (12) after which the position flag is sent, and the rotor stops at the position (12). .

  FIG. 21 is an explanatory diagram showing an example of the relationship between the stator position of the stepping motor, the stop command flag, and the stop position. For example, when the rotation direction is “forward rotation”, the operation excitation mode is “W1-2 phase”, and the stop excitation mode is “1-2 phase”, the position corresponding to the stop excitation mode “1-2 phase” When a position flag is sent out and a stop command flag is sent between positions (4) and (5), a stop position flag is sent at position (6), which is the closest 1-2 phase position in forward rotation. The rotor stops at position (6).

  Further, when the rotation direction is “counter-rotation”, the operation excitation mode is “W1-2 phase”, and the stop excitation mode is “2 phase”, the position flag is set at the position corresponding to the stop excitation mode “2 phase”. When the stop command flag is sent between the positions (0) and (15), the stop position flag is sent at the position (12) which is the closest two-phase position in the counter rotation, and the rotor is moved to the position (12 ) To stop.

(Third embodiment)
A third embodiment will be described with reference to the accompanying drawings. When stopping the stepping motor, the motor driving apparatus according to the third embodiment controls the rotor to stop at a position corresponding to the excitation mode for driving the stepping motor next.

  With respect to the configuration example of the motor drive device according to the present exemplary embodiment, portions different from those of the first exemplary embodiment will be described. The other parts are the same as those in the first embodiment, so the description is omitted with reference to the above description. FIG. 22 is a block diagram illustrating a configuration of a motor drive device according to the third embodiment.

  The motor driving apparatus 300 according to the present embodiment includes a stepping motor 101, a motor driver 102, a motor control unit 303, a control pattern information acquisition unit 104, a setting information acquisition unit 105, and a motor control information generation unit 106. The control pattern information storage unit 110 and the motor control information storage unit 120 are provided. Here, the stepping motor 101, the motor driver 102, the control pattern information acquisition unit 104, the setting information acquisition unit 105, the motor control information generation unit 106, the control pattern information storage unit 110, and the motor control information storage unit 120. Since the configuration and function are the same as those in the first embodiment, description thereof will be omitted.

  The motor control unit 303 further includes a control pattern generation unit 3031 and a stop position determination unit 1032. Since the configuration and function of the stop position determination unit 1032 are the same as those in the first embodiment, description thereof is omitted.

  In addition to the functions and configurations described in the first embodiment, the control pattern generation unit 3031 generates a control pattern corresponding to the position corresponding to the next operating excitation mode stored in the motor control information storage unit 130. When sending to the driver 102, a position flag is sent to the stop position determination unit 1032. As a result, the stop position determination unit 1032 can determine the position corresponding to the excitation mode to be operated next as the stop position.

  Next, motor drive control processing by the motor control unit configured as described above will be described. FIG. 23 is a flowchart illustrating a motor drive control processing procedure performed by the motor control unit. Since the procedure of the motor drive control process according to the present embodiment is almost the same as the flowchart shown in FIG. 8, only different parts will be described. For steps S2301 to S2309 and steps S2312 to S2315, refer to the description in FIG.

  In step S2310, the control pattern generation unit 3031 determines whether or not the control pattern sent to the motor driver 102 is a position corresponding to the excitation mode to be operated next (step S2310). For example, when the excitation mode to be operated next is “1-2 phase”, the positions (0), (2), (4), (6), (8), (10), (12), ( It is determined whether or not any of 14). If it is determined that the control pattern is a position corresponding to the excitation mode to be operated next (step S2310: Yes), a position flag is sent to the stop position determination unit 1032 (step S2311). If it is determined that the control pattern is not at a position corresponding to the excitation mode to be operated next (step S2310: No), the process returns to step S2304.

  Thus, when the rotor moves to a position corresponding to the excitation mode that operates next, the position flag is sent out, so that the rotor can be stopped at the position corresponding to the excitation mode that operates next. Therefore, since the amount of movement of the rotor does not become unstable when the motor is restarted, the read image is not displaced, and the image can be read with high accuracy.

  As mentioned above, although this invention has been demonstrated using the 1st-3rd embodiment, a various change or improvement can be added to embodiment mentioned above. Moreover, the structure and function demonstrated in the 1st-3rd embodiment mentioned above can be combined freely.

It is a block diagram which shows the structure of the motor drive device concerning 1st Embodiment. It is explanatory drawing which shows an example of the position which a rotor moves in each of the position of the stator and excitation mode in a stepping motor. It is explanatory drawing which showed the address corresponding to the position of a stator, and the address to which a rotor is attracted for every excitation mode. It is explanatory drawing which shows an example of a data structure of a control pattern information storage part. It is explanatory drawing which shows an example of a data structure of a motor control information storage part. It is explanatory drawing which graphed an example of the motor control information with the rotational speed and elapsed time of the rotor. It is explanatory drawing which shows an example of the value which the rotation direction which is motor control information, an excitation mode, and the repetition frequency can take. It is a flowchart which shows the motor drive control processing procedure which a motor control part performs. It is a flowchart which shows the address control processing procedure which a control pattern production | generation part performs. It is explanatory drawing which shows an example of the address control process which a control pattern production | generation part performs. It is a flowchart which shows the stop position determination processing procedure which a stop position determination part performs. It is explanatory drawing which shows the relationship between a two-phase position flag, a stop command flag, and a stop position flag. It is a flowchart which shows the control pattern storage process procedure which a control pattern information acquisition part performs. 2 is an explanatory diagram illustrating a hardware configuration of a multifunction peripheral. FIG. It is a block diagram which shows the structure of the motor drive device concerning 2nd Embodiment. It is explanatory drawing which shows an example of the data structure of an address control information storage part, and the value which can be taken. It is a flowchart which shows the motor drive control processing procedure which a motor control part performs. It is a flowchart which shows the address control processing procedure which a control pattern production | generation part performs. It is explanatory drawing which shows an example of address control. It is explanatory drawing which shows an example of the relationship between the present operation excitation mode and stop excitation mode. It is explanatory drawing which shows an example of the relationship between the position of the stator of a stepping motor, a stop command flag, and a stop position. It is a block diagram which shows the structure of the motor drive device concerning 3rd Embodiment. It is a flowchart which shows the motor drive control processing procedure which a motor control part performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multifunction device 100 200 300 Motor drive device 101 Stepping motor 102 Motor driver 103 203 303 Motor control part 104 Control pattern information acquisition part 105 Setting information acquisition part 106 Motor control information generation part 110 Control pattern information storage part 120 Motor control information storage part 230 Address control information storage unit 1031 2031 3031 Control pattern generation unit 1032 Stop position determination unit

Claims (12)

In a motor drive device that has a plurality of excitation modes and is capable of transitioning from one excitation mode to another excitation mode and that drives a stepping motor having a stator fixed to the outer periphery and a rotor attached to a rotating shaft ,
A motor driver that drives the stepping motor by converting a plurality of control patterns that are pulse signals into currents and exciting the stator corresponding to the control patterns;
Motor control means for controlling the stepping motor by outputting any of the plurality of control patterns for moving the rotor to positions corresponding to the plurality of excitation modes to the motor driver ;
When the motor control means uses the control pattern for moving the rotor to a two-phase position, which is a position where the rotor moves in common in the plurality of excitation modes, after the stop of the rotor is instructed. Stop control means for controlling to stop,
Stop excitation mode storage means for storing the excitation mode corresponding to the position where the rotor stops;
Equipped with a,
Each time the motor control means controls the rotor to move to the two-phase position, it sends a position flag indicating that the rotor has been controlled to move to the two-phase position, and stops the rotor. In this case, a stop command flag for instructing the rotor to stop is sent, and when the rotor is controlled to move to a position corresponding to the excitation mode stored in the stop excitation mode storage means, Sending a position flag indicating that the rotor has been controlled to move;
The stop control means, after the stop command flag is sent, determines the position where the position flag is sent as the stop position of the rotor, and stops the rotor at the determined stop position;
The motor drive device characterized by this. The stop excitation mode storage means stores a rotation direction indicating a rotation direction of the rotor together with the excitation mode,
The motor control means is controlled so that the rotor moves to a position corresponding to the excitation mode stored in the stop excitation mode storage means according to the rotation direction stored in the stop excitation mode storage means. , sending a position flag indicating that the rotor in the position is controlled to move, a motor driving device according to claim 1, wherein the. Stop position storage means for storing a position at which the rotor stops;
When the motor control means is controlled to move the rotor to the position stored in the stop position storage means, the motor control means sends a position flag indicating that the rotor is controlled to move to the position. The motor drive device according to claim 1 , wherein: Motor control information storage means for storing the excitation modes for controlling the rotation of the rotor in order of transition;
The motor control means controls the rotor to move to the position when the rotor is controlled to move to a position corresponding to the next excitation mode stored in the motor control information storage means. The motor drive device according to claim 1 , wherein a position flag indicating that the operation has been performed is transmitted. The motor control information storage means stores a rotation direction indicating a rotation direction of the rotor in association with the excitation mode,
The motor control means controls the rotor to move to a position corresponding to the next excitation mode stored in the motor control information storage means according to the rotation direction stored in the motor control information storage means. 5. The motor driving apparatus according to claim 4 , wherein when the control is performed, a position flag indicating that the rotor is controlled to move to the position is transmitted. Control pattern storage means for storing an address corresponding to a position where the rotor moves and a control pattern for driving the stepping motor by moving the rotor to the position in association with each other;
Address acquisition means for acquiring an address corresponding to a position where the rotor moves next time by adding an offset value corresponding to the excitation mode to the address;
Control pattern acquisition means for acquiring the control pattern corresponding to the address acquired by the address acquisition means from the control pattern storage means,
2. The motor control unit according to claim 1, wherein the rotor is moved to the position by sending the control pattern acquired by the control pattern acquisition unit to a motor driver. Motor drive device. The control pattern storage means stores an addition / subtraction address value associated with the address,
The address acquisition means acquires an address corresponding to a position where the rotor moves next time by adding an addition / subtraction address value stored corresponding to the address to a previous address. Item 7. The motor driving device according to Item 6 . The motor control information storage means stores the number of repetitions, which is the number of times the rotor stops at the same position, in association with the excitation mode,
The motor control means controls the position where the rotor moves by sending the control pattern acquired by the control pattern acquisition means according to the number of repetitions stored in the motor control information storage means. The motor driving device according to claim 5 , wherein: The motor drive apparatus according to claim 6 , wherein the control pattern storage unit is stored in a readable / writable storage unit.   An image reading apparatus, wherein an image reading unit is driven by the stepping motor controlled by the motor driving device according to claim 1, thereby reading an original. An image reading apparatus according to claim 10 ,
An image forming apparatus that performs image processing on image information read by the image reading apparatus. A motor drive device that has a plurality of excitation modes, can be changed from one excitation mode to another excitation mode, and drives a stepping motor having a stator fixed to the outer periphery and a rotor attached to a rotating shaft. In the motor driving method to be executed,
A plurality of control patterns that are pulse signals are converted into currents, respectively, and the motor driver that drives the stepping motor by exciting the stator corresponding to the control pattern is positioned at a position corresponding to the plurality of excitation modes. by outputting one of a plurality of said control pattern for moving the rotor, and a motor control step of controlling the stepping motor,
After the stop of the rotor is instructed, the rotor is stopped when the control pattern for moving the rotor to a two-phase position that is a position where the rotor moves in common in the plurality of excitation modes is used. A stop control step to control;
A stop excitation mode storage step for storing the excitation mode corresponding to the position where the rotor stops;
Only including,
In the motor control step, each time the rotor is controlled to move to the two-phase position, a position flag indicating that the rotor has been controlled to move to the two-phase position is sent, and the rotor is controlled to stop. A stop command flag for instructing to stop the rotor is sent to the position when the rotor is controlled to move to a position corresponding to the excitation mode stored in the stop excitation mode storage step. Sending a position flag indicating that the rotor has been controlled to move;
In the stop control step, after the stop command flag is sent, the position where the position flag is sent is determined as the stop position of the rotor, and the rotor is stopped at the determined stop position;
A motor driving method characterized by the above.

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