JP2006033944A - Overheat judging device, method and program of motor, motor controller and control method, and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To estimate the temperature state of a motor accurately based on the driving amount thereof. <P>SOLUTION: The overheat judging device of a motor comprises a section for acquiring information about the driving amount of a judgment object motor and information about the driving amount of other motor being driven alternately with the judgment object motor, a section performing an operation for sequentially integrating the driving amount of the judgment object motor based on the information about the driving amount thereof acquired at the information acquiring section and an operation for subtracting a value corresponding to the driving amount of other motor acquired based on the information about the driving amount thereof acquired at the information acquiring section from the integrated value, and a section for judging that the judgment object motor is in overheated state if the integrated value subtracted at the operating section reaches a predetermined value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a motor overheat determination apparatus, a motor overheat determination method, a motor overheat determination program, a motor control apparatus, a motor control method, and a printing apparatus that determine whether or not a motor is in an overheated state.

  Various printing motors such as inkjet printers have various motors such as a conveyance motor for conveying a medium such as paper to be printed and a motor for moving a printing unit for printing on a medium such as paper. Is installed. In such a motor, when it is continuously driven, heat is generated and the temperature rises, which may result in a high temperature state. Since there is a possibility that problems such as burning of the winding may occur when the motor is in a high temperature state, the printing apparatus is provided with a monitoring device for preventing the motor from being in a high temperature state.

  As one of the monitoring devices, there is a device that monitors the temperature state of the motor based on the driving amount of the motor (see Patent Document 1). This device sequentially accumulates the drive amount of the motor, and checks whether the accumulated value has reached a predetermined value to check whether the motor is in a high temperature state. That is, the temperature of the motor is estimated from the driving amount of the motor by paying attention to the relationship between the driving amount of the motor and the heat generation of the motor. When the integrated value of the drive amount of the motor reaches a predetermined value, it is determined that the motor is in a high temperature state, and the process proceeds to heat generation restriction control in which the drive of the motor is suppressed and heat generation of the motor is limited. By shifting to this control, the motor is continuously driven while preventing the temperature of the motor from rising further. If the motor is not driven for a while, the integrated value of the motor drive amount is processed so as to be gradually reduced, or if the motor is not driven for a long time, It has been proposed that the integrated value of the driving amount is reset to zero.

By monitoring the temperature state of the motor based on the driving amount of the motor in this way, various sensors such as a temperature sensor can be dispensed with, so that the number of components is not increased and the cost is not increased. be able to.
Japanese Patent No. 2002-186285

  However, the apparatus for monitoring the temperature state of the motor based on the driving amount of the motor has the following problems. That is, if the motor has not been driven for a while, the motor drive amount is gradually subtracted, or if the motor has not been driven for a long time, the integrated value of the motor drive amount will be zero. Although the integrated value has been subtracted according to the temperature state of the motor due to resetting, etc., when the motor stops for a very short time, for example, about 1 second such as several tens to several hundred milliseconds If the motor was stopped for a short time, no action was taken. For this reason, although the motor is not in a high temperature state, it may be determined that the motor is in a high temperature state and the heat generation restriction control may be performed. As a result, it takes extra time for printing, and problems such as a decrease in printing speed may occur.

  The present invention has been made in view of such circumstances, and an object thereof is to more accurately estimate the temperature state of the motor based on the driving amount of the motor.

  The main invention for achieving the object is an information acquisition unit that acquires information on a driving amount of a determination target motor and information on a driving amount of another motor that is driven alternately with the determination target motor; An operation for calculating an integrated value by sequentially integrating the driving amount of the determination target motor based on information regarding the driving amount of the determination target motor acquired by the information acquisition unit, and the other information acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value, and an integrated value subtracted by the calculating unit is predetermined. And a determination unit that determines that the determination target motor is in an overheated state when the value reaches a value.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

=== Summary of disclosure ===
At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

An information acquisition unit for acquiring information on a driving amount of a determination target motor and information on a driving amount of another motor driven alternately with the determination target motor;
An operation for calculating an integrated value by sequentially integrating the driving amount of the determination target motor based on information regarding the driving amount of the determination target motor acquired by the information acquisition unit, and the other information acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the determination target motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
An overheat determination device for a motor, comprising:

  In this apparatus, in addition to the calculation of sequentially integrating the drive amount of the determination target motor and calculating the integrated value, the device is acquired based on information on the drive amount of another motor that is driven alternately with the determination target motor. Further, since the calculation for subtracting the subtraction value corresponding to the driving amount of the other motor from the integrated value is executed, the temperature state of the motor can be estimated more accurately.

  In the overheat determination device, the information related to the drive amount of the determination target motor may be acquired by the information acquisition unit every time the determination target motor is driven. In this way, if information regarding the drive amount of the determination target motor is sequentially acquired for each drive of the determination target motor, the temperature state of the determination target motor can be estimated more accurately.

  In the overheat determination device, the information regarding the drive amount of the determination target motor may be acquired by the information acquisition unit before the determination target motor is driven based on the drive amount. As described above, if the information on the driving amount of the determination target motor is acquired before the determination target motor is driven based on the driving amount, the temperature state of the determination target motor can be estimated before driving.

  In the overheat determination device, the calculation unit may perform a calculation of subtracting a predetermined value from the integrated value every time a predetermined time elapses after driving of the determination target motor is stopped. good. If such calculation is executed, the temperature state of the determination target motor can be estimated more accurately.

  In such an overheat determination device, when the determination target motor is determined to be in an overheated state by the determination unit, driving of the determination target motor may be limited. If the drive of the determination target motor is limited in this way, the determination target motor can be driven while suppressing the temperature rise of the determination target motor.

  Moreover, in this overheat determination apparatus, you may provide the table with which the drive amount of the said other motor and the said subtraction value were matched. If such a table is provided, the subtraction value can be easily obtained.

  In the overheat determination device, the information acquisition unit acquires information on the drive mode of the determination target motor, and the subtraction value is information on the drive mode acquired by the information acquisition unit and the information You may acquire based on the information regarding the drive amount of another motor. Thus, by acquiring information related to the drive mode of the determination target motor and acquiring a subtraction value based on the information related to the drive mode, a subtraction value corresponding to the drive mode can be acquired.

  In the overheat determination device, at least one of acceleration during acceleration, speed during constant speed, and acceleration during deceleration may be different depending on the drive mode. Thus, when a motor changes with drive modes, an appropriate subtraction value can be acquired.

An information acquisition unit for acquiring information on a driving amount of a determination target motor and information on a driving amount of another motor driven alternately with the determination target motor;
An operation for calculating an integrated value by sequentially integrating the driving amount of the determination target motor based on information regarding the driving amount of the determination target motor acquired by the information acquisition unit, and the other information acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the determination target motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
Information on the driving amount of the determination target motor is acquired by the information acquisition unit every time the determination target motor is driven, and is acquired by the information acquisition unit before the motor is driven based on the driving amount. And
The calculation unit performs a calculation of subtracting a predetermined value from the integrated value every time a predetermined time has elapsed after the driving of the determination target motor is stopped,
When the determination target motor is determined to be in an overheated state by the determination unit, driving of the determination target motor is limited,
A table in which the driving amount of the other motor is associated with the subtraction value;
The information acquisition unit acquires information on the drive mode of the motor,
The subtraction value is acquired based on information on the drive mode acquired by the information acquisition unit and information on the drive amount of the other motor,
The motor determination apparatus according to claim 1, wherein the determination target motor has at least one of acceleration at acceleration, speed at constant speed, and acceleration at deceleration according to the drive mode.

Obtaining information on the driving amount of the motor to be determined;
Obtaining information relating to the drive amount of another motor driven alternately with the determination target motor;
Calculating the integrated value by sequentially integrating the drive amount of the determination target motor based on the acquired information on the drive amount of the determination target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the determination target motor is in an overheated state when the subtracted integrated value reaches a predetermined value;
A method for determining overheating of a motor, comprising:

Obtaining information on the driving amount of the motor to be determined;
Obtaining information relating to the drive amount of another motor driven alternately with the determination target motor;
Calculating the integrated value by sequentially integrating the drive amount of the determination target motor based on the acquired information on the drive amount of the determination target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the determination target motor is in an overheated state when the subtracted integrated value reaches a predetermined value;
A motor overheating determination program characterized by executing

An information acquisition unit that acquires information on the drive amount of the motor to be controlled and information on the drive amount of another motor that is driven alternately with the motor to be controlled;
An operation for calculating the integrated value by sequentially integrating the drive amount of the motor to be controlled based on the information on the drive amount of the motor to be controlled acquired by the information acquisition unit, and the other acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the motor to be controlled is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
A controller that controls the drive of the control target motor and controls the drive of the control target motor when the determination unit determines that the control target motor is in an overheated state;
A motor control device comprising:

Obtaining information on the drive amount of the motor to be controlled;
Obtaining information relating to the drive amount of another motor driven alternately with the motor to be controlled;
Calculating the integrated value by sequentially integrating the drive amount of the control target motor based on the acquired information on the drive amount of the control target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the motor to be controlled is in an overheated state when the subtracted integrated value reaches a predetermined value;
Limiting the drive of the control target motor when it is determined that the control target motor is in an overheat state; and
A motor control method characterized by comprising:

A printing section for printing on the medium;
Two motors driven alternately,
An information acquisition unit for acquiring information related to the drive amount of the motor;
Based on information about the driving amount of one motor acquired by the information acquisition unit, an operation for calculating the integrated value by sequentially integrating the driving amount of the one motor, and the driving amount of the other motor acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the information on the integrated value from the integrated value;
A determination unit that determines that the one motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
A printing apparatus comprising:

  In such a printing apparatus, the motor moves a motor for transporting the medium printed by the printing unit and a printing unit that performs printing on the medium relative to the medium. It may be a motor.

=== Overview of Printing Apparatus ===
As an example of a motor overheat determination device according to the present invention, a case where it is mounted on an ink jet printer (printing device) will be described as an example. First, an outline of an inkjet printer (printing apparatus) will be described.

  1 to 4 show the ink jet printer 1. FIG. 1 shows the appearance of the inkjet printer 1. FIG. 2 shows the internal configuration of the inkjet printer 1. FIG. 3 shows the transport section of the inkjet printer 1. FIG. 4 is a block diagram showing the system configuration of the inkjet printer 1.

  As shown in FIG. 1, the inkjet printer 1 has a structure for discharging a medium such as printing paper supplied from the back side from the front side, and an operation panel 2 and a paper discharge unit 3 are provided on the front side. The paper feeding unit 4 is provided on the back side. Various operation buttons 5 and display lamps 6 are provided on the operation panel 2. Further, the paper discharge unit 3 is provided with a paper discharge tray 7 that closes the paper discharge port when not in use. The paper feed unit 4 is provided with a paper feed tray 8 that holds cut paper (not shown). Note that the inkjet printer 1 may include a paper feed structure that can print not only on single-sheet-like printing paper such as cut paper but also on continuous media such as roll paper.

  Inside the ink jet printer 1, a carriage 41 is provided as shown in FIG. The carriage 41 is provided so as to be relatively movable along a predetermined direction (the carriage movement direction in the figure). Around the carriage 41, a carriage motor 42, a pulley 44, a timing belt 45, and a guide rail 46 are provided. The carriage motor 42 is constituted by a DC motor or the like, and functions as a drive source for relatively moving the carriage 41 along the predetermined direction. The timing belt 45 is connected to the carriage motor 42 via the pulley 44, and a part of the timing belt 45 is connected to the carriage 41. The carriage 41 is relatively moved along the predetermined direction by the rotation of the carriage motor 42. Move. The guide rail 46 guides the carriage 41 along the predetermined direction.

  In addition, around the carriage 41, a linear encoder 51 that detects the position of the carriage 41, a conveyance roller 17 </ b> A for conveying the medium S along a direction that intersects the moving direction of the carriage 41, and this conveyance A conveyance motor 15 that rotates the roller 17A is provided.

  On the other hand, the carriage 41 is provided with an ink cartridge 48 that stores various inks, and a head 21 that performs printing on the medium S. The ink cartridge 48 contains, for example, each color ink such as yellow (Y), magenta (M), cyan (C), black (K), and is detachable from a cartridge mounting portion 49 provided on the carriage 41. It is attached to. In the present embodiment, the head 21 performs printing by ejecting ink onto the medium S. For this purpose, the head 21 is provided with a number of nozzles for ejecting ink. The ink ejection mechanism of the head 21 will be described in detail later.

  In addition, a cleaning unit 30 for eliminating clogging of the nozzles of the head 21 is provided inside the ink jet printer 1. The cleaning unit 30 includes a pump device 31 and a capping device 35. The pump device 31 is a device that sucks out ink from the nozzles in order to eliminate clogging of the nozzles of the head 21, and is operated by a pump motor (not shown). On the other hand, the capping device 35 seals the nozzles of the head 21 when printing is not performed (for example, during standby) in order to prevent clogging of the nozzles of the head 21.

  Next, the configuration of the transport unit of the inkjet printer 1 will be described. As shown in FIG. 3, the transport unit includes a paper insertion port 11A and a roll paper insertion port 11B, a paper feed motor (not shown), a paper feed roller 13, a platen 14, a transport motor 15, and a transport roller. 17A, a discharge roller 17B, a free roller 18A, and a free roller 18B.

  The paper insertion slot 11A is where the medium S, which is a medium, is inserted. The paper feed motor (not shown) is a motor that transports the medium S inserted into the paper insertion slot 11A into the ink jet printer 1, and is configured by a pulse motor or the like. The paper feed roller 13 is a roller that automatically conveys the medium S inserted into the paper insertion slot 11A into the ink jet printer 1 in the direction of arrow A in the figure (the direction of arrow B in the case of roll paper). It is driven by a motor. The paper feed roller 13 has a substantially D-shaped cross section. Since the circumferential length of the circumferential portion of the paper feed roller 13 is set to be longer than the conveyance distance to the conveyance motor 15, the medium S can be conveyed to the conveyance motor 15 using this circumferential portion.

  The medium S conveyed by the paper supply roller 13 contacts the paper detection sensor 53. The paper detection sensor 53 is installed between the paper feed roller 13 and the transport roller 17A, and detects the medium S fed by the paper feed roller 13.

  The medium S detected by the paper detection sensor 53 is conveyed to the platen 14. The platen 14 is a support unit that supports the medium S during printing. The transport motor 15 is a motor that sends out, for example, paper as the medium S in the transport direction, and is configured by a DC motor. The transport roller 17 </ b> A is a roller that feeds the medium S transported into the inkjet printer 1 by the paper feed roller 13 to a printable region, and is driven by the transport motor 15. The free roller 18A is provided at a position facing the conveyance roller 17A and sandwiches the medium S between the conveyance roller 17A.

  The paper discharge roller 17B is a roller that discharges the medium S on which printing has been completed to the outside of the inkjet printer 1. The paper discharge roller 17B is driven by the transport motor 15 by a gear (not shown). The free roller 18B is provided at a position facing the paper discharge roller 17B, and presses the medium S toward the paper discharge roller 17B by sandwiching the medium S between the paper discharge roller 17B.

<System configuration>
Next, the system configuration of the inkjet printer 1 will be described. As shown in FIG. 4, the inkjet printer 1 includes a buffer memory 122, an image buffer 124, a controller 126, a main memory 127, and an EEPROM 129. The buffer memory 122 receives and temporarily stores various data such as print data transmitted from the computer 140. The image buffer 124 acquires the received print data from the buffer memory 122 and stores it. The main memory 127 is composed of a ROM, a RAM, and the like.

  On the other hand, the controller 126 reads a control program from the main memory 127 or the EEPROM 129, and controls the entire inkjet printer 1 according to the control program. The controller 126 according to this embodiment includes a carriage motor control unit 128, a conveyance control unit 130, a head drive unit 132, a rotary encoder 134, and a linear encoder 51. The carriage motor control unit 128 drives and controls the rotation direction, rotation speed, torque, and the like of the carriage motor 42. Further, the head drive unit 132 performs drive control of the head 21. The conveyance control unit 130 controls various drive motors arranged in the conveyance system, such as the conveyance motor 15 that rotationally drives the conveyance roller 17A.

  The print data sent from the computer 140 is temporarily stored in the buffer memory 122. The controller 126 reads out necessary information from the print data stored here. Based on the read information, the controller 126 refers to the outputs from the linear encoder 51 and the rotary encoder 134, and controls the carriage motor control unit 128, the transport control unit 130, and the head drive unit 132 according to the control program. Control.

  The image buffer 124 stores print data of a plurality of color components received by the buffer memory 122. The head drive unit 132 acquires print data of each color component from the image buffer 124 according to a control signal from the controller 126, and drives and controls the nozzles of each color provided in the head 21 based on the print data.

  The controller 126 receives a signal output from the paper detection sensor 53 and indicating whether or not the medium S is detected. Thereby, the controller 126 can know whether or not the paper detection sensor 53 is detecting the medium S.

<Head>
FIG. 5 is a diagram showing the arrangement of the ink nozzles provided on the lower surface of the head 21. On the lower surface of the head 21, as shown in the figure, nozzles comprising a plurality of nozzles # 1 to # 180 for each color of yellow (Y), magenta (M), cyan (C), and black (K). Groups 211Y, 211M, 211C, and 211K are provided.

  The nozzles # 1 to # 180 of the nozzle groups 211Y, 211M, 211C, and 211K are arranged linearly along the transport direction of the medium S. The nozzle groups 211Y, 211M, 211C, and 211K are arranged in parallel with a space between each other along the movement direction (carriage movement direction) of the head 21. Each nozzle # 1 to # 180 is provided with a piezo element (not shown) as a drive element for ejecting ink droplets.

  When a voltage having a predetermined time width is applied between the electrodes provided at both ends of the piezoelectric element, the piezoelectric element expands according to the voltage application time and deforms the side wall of the ink flow path. As a result, the volume of the ink flow path contracts according to the expansion and contraction of the piezo element, and the ink corresponding to the contraction is ejected from the nozzles # 1 to # 180 of each color as ink droplets.

=== Printing operation ===
Next, the printing operation of the above-described ink jet printer 1 will be described. Here, “bidirectional printing” will be described as an example. FIG. 6 is a flowchart showing an example of the processing procedure of the printing operation of the inkjet printer 1. Each process described below is executed by the controller 126 reading out a program stored in the main memory 127 or the EEPROM 129 and controlling according to the program.

  Upon receiving print data from the computer 140, the controller 126 first performs a paper feed process to execute printing based on the print data (S102). The paper feed process is a process of supplying the medium S to be printed into the ink jet printer 1 and transporting it to a print start position (also referred to as a cue position). The controller 126 rotates the paper feed roller 13 to send the medium S to be printed to the transport roller 17A. The controller 126 rotates the transport roller 17A to position the medium S sent from the paper feed roller 13 at the print start position.

  Next, the controller 126 executes a printing process in which the carriage 41 is moved relative to the medium S to perform printing on the medium S. Here, first, forward printing is performed to eject ink from the head 21 while moving the carriage 41 in one direction along the guide rail 46 (S104). The controller 126 drives the carriage motor 42 via the carriage motor control unit 128 to move the carriage 41 and drives the head 21 based on the print data to eject ink. The ink ejected from the head 21 reaches the medium S and is formed as dots.

  After printing is performed in this way, next, a carrying process for carrying the medium S by a predetermined amount is executed (S106). In this transport process, the controller 126 drives the transport motor 15 and rotates the transport roller 17A via the transport control unit 130 to transport the medium S by a predetermined amount relative to the head 21 in the transport direction. To do. By this carrying process, the head 21 can print in an area different from the previously printed area.

  After carrying out the carrying process in this way, it is determined whether or not to discharge paper (S108). If there is no other data to be printed on the medium S being printed, a paper discharge process is executed (S116). On the other hand, if there is other data to be printed on the medium S being printed, the return pass printing is executed without performing the paper discharge process (S110). In this backward printing, printing is performed by moving the carriage 41 along the guide rail 46 in the direction opposite to the previous forward printing. Again, the controller 126 rotates the carriage motor 42 through the carriage motor control unit 128 to move the carriage 41 in the reverse direction, and drives the head 21 based on the print data to eject ink. Apply printing.

  After performing the return pass printing, a carrying process is executed (S112), and then a paper discharge determination is made (S114). Here, if there is other data to be printed on the medium S being printed, the paper discharge process is not performed, the process returns to step S104, and the forward printing is executed again (S104). On the other hand, if there is no other data to be printed on the medium S being printed, a paper discharge process is executed (S116).

  After the paper discharge process is performed, next, a print end determination is performed to determine whether or not to end printing (S118). Here, based on the print data from the computer 140, it is checked whether there is a medium S to be printed next. If there is a medium S to be printed next, the process returns to step S102, the paper feed process is executed again, and printing is started. On the other hand, if there is no medium S to be printed next, the printing process is terminated.

=== Conveyance motor drive control ===
<Functions of transport control unit>
The drive control of the carry motor 15 is performed by the carry control unit 130. The transport control unit 130 drives the transport motor 15 by a predetermined drive amount based on a transport command from the controller 126. The carry motor 15 rotates the carry roller 17A and the paper discharge roller 17B according to the commanded driving amount. As a result, the transport roller 17A and the paper discharge roller 17B rotate, and the medium S is transported by a predetermined transport amount. The conveyance amount of the medium S is determined according to the rotation amount of the conveyance roller 17A. Therefore, if the rotation amount of the transport roller 17A can be detected, the transport amount of the medium S can also be detected. Here, a rotary encoder 134 is provided to detect the rotation amount of the transport roller 17A.

<Rotary encoder>
FIG. 7 is an explanatory diagram illustrating the configuration of the rotary encoder 134. The rotary encoder 134 includes a rotary encoder code plate 402 and a detection unit 404.
The rotary encoder code plate 402 is formed in a disc shape as shown in the figure. A large number of small slits 406 are formed at predetermined intervals on the outer peripheral edge of the rotary encoder code plate 402. The rotary encoder code plate 402 is integrally provided adjacent to a large gear 408 that is integrally provided at the shaft end of the conveying roller 17A that conveys the medium S. The large gear 408 is connected to the transport motor 15 via the small gear 410, and rotates via the small gear 410 by the rotational drive of the transport motor 15. Thereby, the conveyance roller 17A is rotated by the rotation drive of the conveyance motor 15, and the rotary encoder code plate 402 is also rotated in synchronization with the large gear 408 and the conveyance roller 17A. On the other hand, the detection unit 404 is provided adjacent to the rotary encoder code plate 402 and detects the amount of rotation of the rotary encoder code plate 402.

<Configuration of detection unit>
FIG. 8 shows the configuration of the detection unit 404 of the rotary encoder 134 in detail. The detection unit 404 includes a light emitting diode 412, a collimator lens 414, and a detection processing unit 416. The detection processing unit 416 includes a plurality (for example, four) of photodiodes 418, a signal processing circuit 420, and, for example, two comparators 422A and 422B.

  When the voltage Vcc is applied to both ends of the light emitting diode 412 via a resistor, light is emitted from the light emitting diode 412. This light is condensed into parallel light by the collimator lens 414 and passes through the rotary encoder code plate 402. The rotary encoder code plate 402 is provided with slits 406 at predetermined intervals (for example, 1/180 inch (1 inch = 2.54 cm)).

  The parallel light that has passed through the rotary encoder code plate 402 enters each photodiode 418 through a fixed slit (not shown), and is converted into an electrical signal. The electric signals output from the four photodiodes 418 are subjected to signal processing in the signal processing circuit 420, the signals output from the signal processing circuit 420 are compared in the comparators 422A and 422B, and the comparison result is output as a pulse. Pulses ENC-A and ENC-B output from the comparators 422A and 422B are output signals of the rotary encoder 134.

  FIGS. 9A and 9B are timing charts showing waveforms of two output signals of the rotary encoder 134 when the transport motor 15 is rotating forward and when rotating reversely. FIG. 9A is a timing chart of the waveform of the output signal when the transport motor 15 is rotating forward. FIG. 9B is a timing chart of the waveform of the output signal when the transport motor 15 is reversed.

  As shown in FIGS. 9A and 9B, the phase of the pulse ENC-A and the pulse ENC-B differ by 90 degrees in both cases of the forward rotation and the reverse rotation of the transport motor 15. When the transport motor 15 is rotating forward, that is, when the medium S is transported in the transport direction as shown in FIG. 7, the phase of the pulse ENC-A is advanced by 90 degrees relative to the pulse ENC-B. On the other hand, when the transport motor 15 is reversed, that is, when the medium S is transported in the direction opposite to the transport direction, the phase of the pulse ENC-A is delayed by 90 degrees from the pulse ENC-B. One period T of each pulse is equal to a time during which the transport roller 17A rotates by an interval (for example, 1/1440 inch (1 inch = 2.54 cm)) of the slit 406 of the rotary encoder code plate 402.

  Then, when the rising edge and rising edge of each of the output pulses ENC-A and ENC-B of the rotary encoder 134 are detected by the system controller 126 and the number of detected edges is counted, the system controller 126 Based on the counted value, the rotational position of the transport motor 15 can be calculated. This count is incremented by “+1” when one edge is detected when the transport motor 15 is rotating forward, and “−” when one edge is detected when the conveyor motor 15 is rotating in reverse. Add 1 ”. The period of each of the pulses ENC-A and ENC-B is the time from when a slit 406 of the rotary encoder code plate 402 passes through the detector 404 until the next slit 406 passes through the detector 404. The pulse ENC-A and the pulse ENC-B are different in phase by 90 degrees. Therefore, the count value “1” corresponds to ¼ of the interval between the slits 406 of the rotary encoder code plate 402. Thus, if the count value is multiplied by 1/4 of the interval of the slits 406, the transport amount of the transport motor 15 from the rotational position corresponding to the count value “0” can be obtained based on the multiplication value. it can. At this time, the resolution of the rotary encoder 134 is ¼ of the interval between the slits 406 of the rotary encoder code plate 402.

<Configuration of transport control unit>
FIG. 10 is a block configuration diagram illustrating an example of a circuit configuration of the transport control unit 130. As shown in the figure, the transport control unit 130 includes a position calculation unit 431, a subtractor 432, a gain 433, a speed calculation unit 434, a subtractor 435, a proportional element 436A, an integration element 436B, A differential element 436C, an adder 437, a PWM circuit 438, an acceleration control unit 439A, and a timer 439B are included.

The position calculation unit 431 detects the edge of the output pulse of the rotary encoder 134, counts the number thereof, and calculates the rotational position of the transport motor 15 based on this count value. The position calculation unit 431 recognizes the normal rotation / reverse rotation of the transport motor 15 from the comparison processing of the two pulse signals, and counts so as to be incremented / decremented according to the normal rotation / reverse rotation when one edge is detected. To do.
The subtractor 432 calculates a position deviation between the target position sent from the controller 126 and the detection position detected by the position calculation unit 431. The gain 433 multiplies the position deviation output from the subtractor 432 by the gain Kp, and outputs a target speed. The gain Kp is determined according to the position deviation. Note that a table indicating the relationship between the value of the gain Kp and the position deviation is stored in the main memory 127.

The speed calculation unit 434 calculates the rotation speed of the transport motor 15 based on the output pulse of the rotary encoder 134. That is, the speed calculation unit 434 measures the pulse period of the output pulse of the rotary encoder 134 and calculates the rotation speed of the transport motor 15 based on this pulse period.
The subtractor 435 calculates a speed deviation between the target speed output from the gain 433 and the detected speed detected by the speed calculator 434.

The proportional element 436A multiplies the speed deviation by a constant Gp and outputs a proportional component. The integration element 436B integrates the speed deviation multiplied by the constant Gi and outputs an integration component. The differential element 436C multiplies the difference between the current speed deviation and the previous speed deviation by a constant Gd, and outputs a differential component. The calculation of the proportional element 436A, the integral element 436B, and the differential element 436C is performed for each cycle of the output pulse of the rotary encoder 134.
The signal values output from the proportional element 436A, the integral element 436B, and the derivative element 436C indicate the duty DX corresponding to the respective calculation results. Here, the duty DX indicates that the duty percentage is (100 × DX / 2000)%, for example. In this case, if DX = 2000, the duty is 100%, and if DX = 1000, the duty is 50%.

  The adder 437 adds the output of the proportional element 436A, the output of the integral element 436B, and the output of the derivative element 436C. The addition result is sent to the PWM circuit 438 as a duty signal. The PWM circuit 438 generates a command signal corresponding to the addition result of the adder 437. The driver 440 drives the carry motor 15 based on this command signal. The driver 440 includes, for example, a plurality of transistors, and applies a voltage to the transport motor 15 by turning on and off the transistors based on a command signal from the PWM circuit 438.

  Further, the acceleration control unit 439A and the timer 439B are used during the acceleration control of the carry motor 15. The timer 439B generates a timer interrupt signal every predetermined time based on the clock signal sent from the controller 126. The acceleration control unit 439A integrates a predetermined duty DXP every time it receives a timer interrupt signal, and outputs a duty signal to the PWM circuit 438 as an integration result.

  When the conveyance motor 15 is accelerated, the PWM circuit 438 outputs a command signal to the conveyance motor 15 based on the duty signal output from the acceleration control unit 439A, and controls the conveyance motor 15. When the conveyance motor 15 is driven at a constant speed and when the conveyance motor 15 is decelerated, the PWM circuit 438 outputs a command signal to the conveyance motor 15 based on the duty signal output from the adder 437, and the conveyance motor 15 15 is PID controlled.

<Motor drive method>
FIG. 11A is a graph of the time change of the duty signal input to the PWM circuit 438. FIG. 11B is a graph of the speed change of the transport motor 15. Hereinafter, the driving of the transport motor 15 will be described with reference to these drawings.

  When the start command signal for starting the transport motor 15 is sent from the controller 126 to the transport control unit 130 while the transport motor 15 is stopped, the start initial duty signal whose signal value is DX0 is sent from the acceleration control unit 439A to the PWM circuit. 438. This startup initial duty signal is sent from the controller 126 to the acceleration control unit 439A together with the startup command signal. The start initial duty signal is converted into a command signal corresponding to the signal value DX0 by the PWM circuit 438, and the start of the transport motor 15 is started.

  After the transport control unit 130 receives the start command signal, a timer interrupt signal is generated from the timer 439B every predetermined time. Every time the acceleration control unit 439A receives a timer interrupt signal, the acceleration control unit 439A accumulates a predetermined duty DXP on the signal value DX0 of the startup initial duty signal, and sends a duty signal having the accumulated duty as a signal value to the PWM circuit 438. . The duty signal is converted into a command signal corresponding to the signal value by the PWM circuit 438, and the rotation speed of the carry motor 15 increases. For this reason, the value of the duty signal sent from the acceleration control unit 439A to the PWM circuit 438 increases stepwise.

  The duty integration process in the acceleration control unit 439A is performed until the integrated duty reaches a predetermined duty DXS. When the duty integrated at time t1 reaches a predetermined value DXS, the acceleration control unit 439A stops the integration process, and thereafter sends a duty signal having a constant duty DXS as a signal value to the PWM circuit 438.

  When the transport motor 15 reaches a predetermined rotational speed (see time t2), the acceleration control unit 439A decreases the duty signal output to the PWM circuit 438 and decreases the duty percentage of the voltage applied to the transport motor 15. To control. At this time, the rotation speed of the transport motor 15 further increases. At time t3, the PWM circuit 438 selects the output of the adder 437, and PID control is performed. At the time (t3) when the PID control is started, the integral value of the integral element 436B is set to an appropriate value, and the output value of the integral element 436B becomes a predetermined value.

  When the PID control is started, the conveyance control unit 130 calculates the target rotational speed by multiplying the position deviation between the target rotational position and the actual rotational position obtained from the output of the rotary encoder 134 by the gain Kp. Then, the conveyance control unit 130 uses the proportional element 436A, the integral element 436B, and the differential element 436C based on the speed deviation between the target rotational speed and the actual rotational speed obtained from the output of the rotary encoder 134. The component, integral component, and derivative component are calculated, and the transport motor 15 is controlled based on the sum of these calculation results. The proportional, integral, and differential calculations are performed in synchronization with the rising edge of the output pulse ENC-A of the rotary encoder 134, for example. Thereby, the rotation speed of the conveyance motor 15 is controlled to be a desired rotation speed at time t4.

  When the transport motor 15 approaches the target rotation position (time t5), the position deviation decreases, so the target rotation speed also decreases. For this reason, the speed deviation, that is, the output of the subtractor 435 becomes negative, the transport motor 15 decelerates, and stops at time t6.

=== Carriage motor drive control ===
<Function of carriage motor control unit>
Driving control of the carriage motor 42 is performed by the carriage motor control unit 128. The carriage motor control unit 128 drives the carriage motor 42 by a predetermined driving amount based on a carriage movement command from the controller 126. The carriage motor 42 is driven by the commanded predetermined drive amount. The moving amount of the carriage 41 is determined according to the driving amount of the carriage motor 42. In the present embodiment, the movement amount of the carriage 41 is detected by the linear encoder 51. While monitoring the output from the linear encoder 51, the carriage motor control unit 128 drives the carriage motor 42 by an instructed predetermined driving amount to move the carriage 41 by a predetermined distance.

  Similar to the rotary encoder 134, the linear encoder 51 includes a linear encoder code plate 511 and a detector (not shown). As shown in FIG. 2, the linear encoder code plate 511 is attached to the frame side inside the inkjet printer 1. On the other hand, the detection unit (not shown) is attached to the carriage 41 side. The detection unit has a configuration substantially equal to the configuration of the detection unit 404 of the rotary encoder 134 as described with reference to FIGS. 8 and 9. That is, the detection unit outputs two different pulse signals according to the rotation direction of the carriage motor 42, that is, the movement direction of the carriage 41. The linear encoder code plate 511 and the detection unit (not shown) can detect the current position of the carriage 41.

<Configuration of carriage motor control unit>
The configuration of the carriage motor control unit 128 will be described in detail. FIG. 12 is a block configuration diagram illustrating an example of a circuit configuration of the carriage motor control unit 128. The carriage motor control unit 128 has substantially the same configuration as the conveyance control unit. That is, as shown in the figure, the carriage motor control unit 128 includes a position calculation unit 331, a subtracter 332, a gain 333, a speed calculation unit 334, a subtractor 335, a proportional element 336A, and an integration element 336B. A differential element 336C, an adder 337, a PWM circuit 338, an acceleration control unit 339A, and a timer 339B.

The position calculation unit 331 detects the edge of the output pulse of the linear encoder 51, counts the number thereof, and calculates the rotational position of the carriage motor 42 based on the count value. The position calculation unit 331 recognizes normal rotation / reverse rotation of the carriage motor 42 from the comparison processing of the two pulse signals from the linear encoder 51, and increments according to normal rotation / reverse rotation when one edge is detected. Counting process to decrement.
The subtractor 332 calculates a position deviation between the target position sent from the controller 126 and the detected position detected by the position calculation unit 331. The gain 333 multiplies the position deviation output from the subtracter 332 by the gain Kp, and outputs a target speed. The gain Kp is determined according to the position deviation.

The speed calculation unit 334 measures the pulse period of the output pulse of the linear encoder 51 and calculates the rotation speed of the carriage motor 42 based on this pulse period.
The subtractor 335 calculates a speed deviation between the target speed output from the gain 333 and the detected speed detected by the speed calculator 334.

The proportional element 336A multiplies the speed deviation by a constant Gp and outputs a proportional component. The integration element 336B integrates the speed deviation multiplied by the constant Gi and outputs an integration component. The differential element 336C multiplies the difference between the current speed deviation and the previous speed deviation by a constant Gd, and outputs a differential component. The calculation of the proportional element 336A, the integral element 336B, and the differential element 336C is performed for each cycle of the output pulse of the linear encoder 51.
The signal values output from the proportional element 336A, the integral element 336B, and the differential element 336C indicate the duty DX corresponding to the respective calculation results.

  The adder 337 adds the output of the proportional element 336A, the output of the integral element 336B, and the output of the derivative element 336C. The addition result is sent to the PWM circuit 338 as a duty signal. The PWM circuit 338 generates a command signal corresponding to the addition result of the adder 337. The driver 340 drives the carriage motor 42 based on this command signal. The driver 340 includes a plurality of transistors, for example, and applies a voltage to the carriage motor 42 by turning on and off the transistors based on a command signal from the PWM circuit 338.

  The acceleration control unit 339A and the timer 339B are used during acceleration control of the carriage motor 42. The timer 339B generates a timer interrupt signal every predetermined time based on the clock signal sent from the controller 126. The acceleration control unit 339A integrates a predetermined duty DXP every time a timer interrupt signal is received, and outputs a duty signal to the PWM circuit 338 as an integration result.

  When the carriage motor 42 is accelerated, the PWM circuit 338 outputs a command signal to the carriage motor 42 based on the duty signal output from the acceleration control unit 339A to control the carriage motor 42. When the carriage motor 42 is driven at a constant speed and when the carriage motor 42 is decelerated, the PWM circuit 338 outputs a command signal to the carriage motor 42 based on the duty signal output from the adder 337, and the carriage motor 42 42 is PID controlled.

  Here, the duty signal input to the PWM circuit 338 is, for example, a signal as shown in FIG. The speed change of the carriage motor 42 at this time is as shown in FIG. 11B as in the case of the conveyance control unit 130. The carriage motor control unit 128 controls the driving of the carriage motor 42 in the same manner as when the conveyance control unit 130 controls the driving of the conveyance motor 15.

=== Motor overheat judgment ===
When such a conveyance motor 15 is continuously driven, the conveyance motor 15 generates heat and the temperature rises, which may result in a high temperature state. Thus, when the conveyance motor 15 is in a high temperature state, for example, a defect such as the winding being burned out may occur. Therefore, the ink jet printer 1 of the present embodiment includes an overheat determination device that determines whether or not the conveyance motor 15 is in an overheated state before the conveyance motor 15 is in a high temperature state in order to prevent such a problem from occurring. ing. In the present embodiment, the conveyance motor 15 corresponds to the “determination target motor” of the present invention.

<Overheating judgment overview>
This overheat determination device sequentially accumulates the drive amount of the conveyance motor 15 and checks whether or not the accumulated value has reached a predetermined value, thereby determining whether or not the conveyance motor 15 is in an overheated state. When it is determined by the overheat determination device that the transport motor 15 is in an overheated state, heat generation restriction control is executed on the transport motor 15. The heat generation restriction control is control for allowing the conveyance motor 15 to have a cooling time for radiating heat as necessary. Specifically, an extra standby time is provided each time the transport motor 15 is driven once. Thereby, the temperature of the conveyance motor 15 can be slightly lowered until the conveyance motor 15 is driven next time, and it is possible to prevent the temperature from being excessively increased even if the conveyance motor 15 is driven next time. Therefore, by executing such heat generation restriction control, it is possible to continue the printing process while suppressing the temperature increase of the carry motor 15.

  In the inkjet printer 1 of the present embodiment, acquisition of information related to the drive amount of the carry motor 15, calculation for sequentially integrating the drive amount of the carry motor 15 to obtain an integrated value, and the obtained integrated value reaches a predetermined value. The controller 126 checks whether or not it has been performed. That is, the controller 126 of the present embodiment corresponds to the information acquisition unit, calculation unit, and determination unit of the present invention.

<Actual overheating judgment>
FIG. 13 briefly describes an example of a control state when the conveyance motor 15 is actually driven. When the ink jet printer 1 starts the printing process, the transport motor 15 is driven to transport the medium S. When the carry motor 15 is driven, the drive amount (here, the drive amount of the carry motor 15 is expressed in units of number of steps (number of steps), hereinafter also referred to as “PFstep”) is sequentially accumulated. The The controller 126 sequentially accumulates the conveyance amount of the conveyance motor 15 instructed by the conveyance command transmitted to the conveyance control unit 130. That is, when the controller 126 transmits a conveyance command for 200 steps as the conveyance amount to the conveyance control unit 130, the controller 126 adds 200 steps. Further, when the controller 126 transmits a conveyance command for 300 steps as the driving amount to the conveyance control unit 130, the existing integrated value (currently “200”) for 300 steps is added. As a result, the integrated value becomes “500”. In this way, the controller 126 sequentially accumulates the drive amount of the transport motor 15 that is instructed to the transport control unit 130. In the present embodiment, the integrated value calculated by the controller 126 is referred to as “Psum”.

  FIG. 14 shows an example of integration of the driving amount PFstep (number of driving steps) of the transport motor 15 by the controller 126. As shown in the figure, the integrated value Psum becomes “350” when the transport motor 15 is driven “200 steps” and then “150 steps” is driven next. Further, when the conveyance motor 15 is driven by “250 steps”, the integrated value Psum becomes “600”. Next, when the transport motor 15 is driven by “100 steps”, the integrated value Psum becomes “700”. When the conveyance motor 15 is driven by “50 steps”, the integrated value Psum becomes “750”. In this way, each time the transport motor 15 is driven, the drive amount PFstep is sequentially integrated to the integrated value Psum.

  As the printing process proceeds, the integrated value Psum calculated by the controller 126 gradually increases. Here, when the integrated value Psum reaches a predetermined value (herein referred to as “Pduty”) at time t1, the controller 126 determines that the transport motor 15 is in an overheated state and transports the transport motor 15 to the transport motor 15. Heat generation restriction control is started through the control unit 130. As described above, this heat generation restriction control is a control for providing an extra standby time as needed every time the transport motor 15 is driven once. Thereby, the conveyance motor 15 is continuously driven while suppressing the temperature rise of the conveyance motor 15.

  FIG. 15 illustrates an operation state of the transport motor 15 when the transport motor 15 is subjected to the heat generation restriction control and when the transport motor 15 is in the normal time when the heat generation restriction control is not performed. FIG. 15A shows a normal case where the heat generation restriction control is not performed, and FIG. 15B shows a case where the heat generation restriction control is performed.

  When the heat generation restriction control is not performed, the conveyance motor 15 is driven alternately with the carriage motor 42 during the printing process, as shown in FIG. 15A. That is, when the transport motor 15 is driven, the drive of the carriage motor 42 is stopped, and when the transport motor 15 is stopped, the carriage motor 42 is driven. When the driving of the carriage motor 42 is completed, the driving of the transport motor 15 is immediately started.

  On the other hand, when the heat generation restriction control is performed, as shown in FIG. 15B, the transport motor 15 does not immediately start driving the transport motor 15 even when the drive of the carriage motor 42 is completed. That is, the conveyance motor 15 is not driven for a while after the drive period of the carriage motor 42 is finished, and is resumed after a predetermined waiting time has elapsed. This is a measure for preventing the temperature of the transport motor 15 from excessively increasing when the transport motor 15 is driven next time, in order to give a sufficient cooling time to the transport motor 15 that has fallen into an overheated state. Thereby, the conveyance motor 15 can be driven while the temperature increase of the conveyance motor 15 is suppressed, and the printing process can be continued. In this way, the printing process is completed while suppressing the temperature rise of the transport motor 15.

  As shown in FIG. 13, after the printing process is completed at time t <b> 2, if there is no print command from the user for a while and the print standby state continues, the controller 126 drives the transport motor 15. The integrated value Psum of the amount PFstep is gradually reduced with time. Here, every time the predetermined time Δtm elapses, the controller 126 executes a calculation process of subtracting the integrated value Psum by the predetermined value ΔPm. In this way, the controller 126 gradually decreases the integrated value Psum by the predetermined value ΔPm until a new print command is issued from the user.

  Here, if the user gives a command to turn off the power of the inkjet printer 1 at time t3, the controller 126 sets the accumulated value Psum at that time in the main memory 127 or the like as appropriate when turning off the power. Stored in a storage unit. Then, the integrated value Psum is stored and held while the power of the inkjet printer 1 is OFF.

  When the user turns on the ink jet printer 1 again at time t4, the controller 126 reads the accumulated value Psum stored from the main memory 127 or the like. When the printing process is started again, the driving amount PFstep of the transport motor 15 is sequentially integrated with the read integrated value Psum, as in the case described above. As a result, as shown in FIG. 13, the integrated value Psum of the drive amount PFstep of the transport motor 15 starts to gradually increase again. When the integrated value Psum reaches the predetermined value Pduty again at time t5, the controller 126 starts heat generation restriction control for the carry motor 15 through the carry control unit 130, and the carry motor 15 is driven once. Each time, an extra standby time is set as necessary. Thereby, the conveyance motor 15 is continuously driven while suppressing the temperature rise of the conveyance motor 15.

  Furthermore, when the printing process is completed at time t6 and the standby state continues without a print command from the user for a while, the controller 126 gradually decreases the integrated value Psum with time. Here again, as in the case described above, the integrated value Psum is decreased by a predetermined value ΔPm every time the predetermined time Δtm elapses.

  When the user issues a print command again at time t7 and print processing is started, the controller 126 sequentially accumulates the driving amount PFstep of the carry motor 15 to the integrated value Psum, and the integrated value Psum gradually increases again. Begin to. Thereafter, when the integrated value Psum reaches the predetermined value Pduty again at time t8, the controller 126 performs the heat generation restriction control on the transport motor 15 again.

<Controller processing>
FIG. 16 is a flowchart for explaining the integration processing procedure of the controller 126. First, the controller 126 sets an initial value for the integrated value Psum (S202). This initial value may be, for example, “zero”, or may be the integrated value Psum before power-off stored in the main memory 127 or the like. Next, the controller 126 checks whether or not information related to the drive amount PFstep of the carry motor 15 has been acquired when sending a carry command to the carry control unit 130 (S204). Here, when the information regarding the drive amount PFstep has not been acquired, the process returns to step S204, and it is checked again whether the information regarding the drive amount PFstep has been acquired (S204). This check is performed until information on the drive amount PFstep is acquired.

If the information related to the drive amount PFstep of the transport motor 15 is acquired, the controller 126 then proceeds to step S206, and adds the acquired drive amount PFstep to the integrated value Psum (S206). After completing this addition process, the controller 126 then checks whether or not the new integrated value Psum obtained by the calculation has reached a predetermined value Pduty that is a criterion for determining whether or not the overheated state is present ( S208). Here, when the new integrated value Psum has reached the predetermined value Pduty, the controller 126 determines that the transport motor 15 is in an overheated state, and passes the transport control unit 130 to the transport motor 15. The heat generation restriction control is started (S210). Thereafter, the controller 126 ends the integration process.
On the other hand, if the new integrated value Psum has not reached the predetermined value Pduty, the controller 126 determines that the transport motor 15 is not yet overheated, returns to step S204, and drives again. An attempt is made to acquire the quantity PFstep (S204).

<Setting of predetermined value Pduty>
A method for setting the predetermined value Pduty, which is a criterion for determining whether or not the transport motor 15 is in an overheated state, will be described. Here, a simulation assuming that the conveyance motor 15 is actually driven is executed, and the predetermined value Pduty is determined based on the result of the simulation. In this simulation, the amount of heat generated when the conveyance motor 15 to be determined is actually driven is obtained. Here, the case where the conveyance motor 15 is driven under the most severe condition (worst condition) is examined. The rising temperature of the conveyance motor 15 is calculated from the amount of heat generated by the conveyance motor 15 in this case, and the conveyance motor 15 until reaching the limit temperature at which the conveyance motor 15 can be safely used (hereinafter also referred to as “limit temperature”) Investigate the total amount of driving.

  The amount of heat generated by the conveyance motor 15 is calculated in consideration of the magnitude of the load on the conveyance motor 15, the effective current flowing through the conveyance motor 15, the temperature characteristics of the windings of the conveyance motor 15, and the like. The most severe conditions are set assuming that the drive time of the carriage motor 42 is extremely short, for example, when the print width in the carriage movement direction is very short, such as when printing vertical lines. The total drive amount of the transport motor 15 is calculated from the drive time of the transport motor 15 that is required until the temperature of the transport motor 15 reaches the limit temperature. In the present embodiment, the total drive amount of the conveyance motor 15 calculated here is referred to as a predetermined value Pduty.

  FIG. 17 is a diagram for explaining an example of how to obtain the predetermined value Pduty. The time required to reach the limit temperature (110 ° C.) with an effective current of 410 mA (equivalent to 260 gcm) is 1000 s. Assuming that the drive amount of the conveyance motor 15 required for printing per A4 size sheet is 15000 steps and the printing time is 10 s (printing processing speed: 6 ppm), the conveyance motor 15 reaches the limit temperature. The number of sheets that can be printed is 1000 s / 10 s, which is approximately 100 sheets. From this, the predetermined value Pduty becomes 15000 × 100, and a value of 1500,000 is obtained.

=== Differences from the past ===
Conventionally, when the transport motor 15 is not driven for a while, the integrated value Psum is gradually subtracted, and when the transport motor 15 is not driven for a long time, the integrated value Psum is zero. The integrated value Psum has been reduced so as to match the temperature state of the transport motor 15 by resetting or the like, but when the transport motor 15 stops for a very short time, for example, while the carriage motor 42 is being driven. In the case of stopping for a very short period of time, no measures have been taken against the integrated value Psum.

  For this reason, although the conveyance motor 15 is not in an overheated state, the integrated value Psum may reach a predetermined value Pduty, and it may be determined that the conveyance motor 15 is in an overheated state. When it is determined that the transport motor 15 is in an overheated state, the heat generation restriction control is executed, and an extra standby time is generated for cooling the transport motor 15, so that the printing time becomes longer and the printing process is delayed. There was a case.

  In the inkjet printer 1 according to the present embodiment, in order to solve such a problem, even when the carry motor 15 is stopped while the carriage motor 42 is being driven, the carriage motor 42 is being stopped. The integrated value Psum is reduced according to the drive amount. That is, each time the conveyance motor 15 is stopped and the carriage motor 42 is driven, a value corresponding to the driving amount (corresponding to a subtraction value of the present invention; hereinafter, also referred to as “Psub” in the present embodiment) is an integrated value. Subtract from Psum. At this time, the controller 126 performs a process of subtracting the value “Psub” corresponding to the driving amount of the carriage motor 42 from the integrated value Psum. In this embodiment, the carriage motor 42 corresponds to “another motor” of the invention.

=== Outline of processing ===
FIG. 18 explains the outline of this processing. The controller 126 acquires information on the driving amount PFstep before the transport motor 15 is driven, and adds the driving amount PFstep to the integrated value Psum. Further, the controller 126 acquires information regarding the driving amount when the carriage motor 42 is driven. In this case, after the driving of the transport motor 15 is completed, the controller 126 subtracts the subtraction value Psub corresponding to the acquired driving amount of the carriage motor 42 from the integrated value Psum. The controller 126 executes such a subtraction process every time the carriage motor 42 is driven between the driving of the transport motor 15.
Note that the timing at which the controller 126 acquires information related to the drive amount of the carriage motor 42 may be before the carriage motor 42 starts to be driven based on the drive amount, and the drive of the carriage motor 42 is started. It doesn't matter later.

<Controller subtraction processing>
FIG. 19 is a flowchart for explaining an example of the subtraction process executed by the controller 126 at this time. Here, the controller 126 first checks whether or not information on the drive amount of the carriage motor 42 has been acquired (S302). Here, when the information regarding the driving amount of the carriage motor 42 has not been acquired, the process returns to step S302, and it is checked again whether or not the information regarding the driving amount of the carriage motor 42 has been acquired. This check is performed until the controller 126 acquires information regarding the drive amount of the carriage motor 42.

  On the other hand, when the information regarding the driving amount of the carriage motor 42 is acquired, the controller 126 proceeds to step S304, and in accordance with the driving amount of the carriage motor 42 based on the acquired information regarding the driving amount of the carriage motor 42. The subtraction value Psub is acquired (S304). Here, the subtraction value Psub may be obtained from the driving amount of the carriage motor 42 by calculation by the controller 126 or the like, and is obtained from a table in which the driving amount of the carriage motor 42 and the subtraction value Psub are associated with each other. You may make it do.

  Next, the controller 126 proceeds to step S306, and checks whether or not the driving of the carriage motor 42 is completed (S306). Here, if the drive of the carriage motor 42 has not been completed, the process returns to step S306, and it is checked again whether the drive of the carriage motor 42 has been completed. This check is performed until the driving of the carriage motor 42 is completed.

  On the other hand, if the driving of the carriage motor 42 has been completed, the process proceeds to step S308, where a calculation process is performed to subtract the subtraction value Psub corresponding to the acquired driving amount of the carriage motor 42 from the integrated value Psum ( S308). Thereby, the integrated value Psum can be reduced according to the drive amount of the carriage motor 42. After reducing the subtraction value Psub in this way, the controller 126 proceeds to step S310 and checks whether the printing process is completed. If the printing process has not been completed, the controller 126 returns to step S302 and checks again whether or not information on the drive amount of the carriage motor 42 has been acquired (S302). On the other hand, when the printing process is finished, the controller 126 finishes the subtraction process of the integrated value Psum.

<Other processing examples>
In the embodiment described above, the subtraction value Psub corresponding to the driving amount of the carriage motor 42 is subtracted from the integrated value Psum after the driving of the transport motor 15 is completed. This is to prevent the subtraction value Psub from being subtracted from the integrated value Psum before the drive amount PFstep of the transport motor 15 is added to the integrated value Psum, and as much as possible when the transport motor 15 approaches an overheated state. This is because the heat generation restriction control is executed at an early stage. However, the present invention is not limited to such a case. That is, before the drive amount PFstep of the transport motor 15 is added to the integrated value Psum, or at almost the same timing as the drive amount PFstep of the transport motor 15 is added to the integrated value Psum, the subtraction value Psub is the integrated value. It may be subtracted from Psum.

  FIG. 20 illustrates an outline of processing when the addition processing of the driving amount PFstep of the transport motor 15 to the integrated value Psum and the subtraction processing of the subtraction value Psub from the integrated value Psum are performed almost simultaneously. When the carriage motor 42 is driven, the controller 126 acquires information related to the driving amount. Here, the information regarding the driving amount of the carriage motor 42 can be acquired before the carriage motor 42 is driven. Thereafter, the controller 126 acquires a subtraction value Psub corresponding to the drive amount based on the acquired drive amount of the carriage motor 42. Further, the controller 126 can acquire information on the drive amount PFstep before the transport motor 15 is driven.

  Before the driving of the transport motor 15 is started, the controller 126 adds the acquired drive amount PFstep of the transport motor 15 to the integrated value Psum and subtracts the acquired subtraction value Psub from the integrated value Psum. Here, the subtraction value Psub has already been acquired based on the drive amount of the carriage motor 42 acquired before the carriage motor 42 is driven.

  The controller 126 performs the process of adding the driving amount PFstep of the transport motor 15 to the integrated value Psum and the process of subtracting the subtraction value Psub from the integrated value Psum at substantially the same timing. When the controller 126 obtains the driving amount PFstep of the transport motor 15, it immediately executes these addition processing and subtraction processing. The controller 126 executes these addition processing and subtraction processing each time the transport motor 15 is driven.

  FIG. 21 is a flowchart for explaining an outline of processing executed by the controller 126 at this time. First, the controller 126 checks whether or not information related to the drive amount of the carriage motor 42 has been acquired (S402). Here, when the information regarding the drive amount of the carriage motor 42 has not been acquired, the process returns to step S402 to check again whether or not the information regarding the drive amount of the carriage motor 42 has been acquired. This check is performed until the controller 126 acquires information regarding the drive amount of the carriage motor 42.

  On the other hand, when the information regarding the driving amount of the carriage motor 42 is acquired, the controller 126 proceeds to step S304, and in accordance with the driving amount of the carriage motor 42 based on the acquired information regarding the driving amount of the carriage motor 42. The subtraction value Psub is acquired (S404).

  Next, the controller 126 checks whether or not information related to the driving amount of the carry motor 15 has been acquired (S406). Here, when the information regarding the drive amount of the conveyance motor 15 is not acquired, it returns to step S406 and it is checked again whether the information regarding the drive amount of the conveyance motor 15 was acquired. This check is performed until the controller 126 acquires information about the driving amount of the transport motor 15.

  When the information about the driving amount of the transport motor 15 is acquired, the controller 126 includes a process of adding the driving amount PFstep of the transport motor 15 to the integrated value Psum, and a process of subtracting the subtraction value Psub from the integrated value Psum. (S408). That is, the controller 126 updates the integrated value Psum by the arithmetic expression “Psum = Psum + PFstep−Psub”.

  After such calculation processing is completed, the controller 126 checks whether the printing processing is completed (S410). If the printing process has not been completed, the controller 126 returns to step S402 and checks whether new information regarding the drive amount of the carriage motor 42 has been acquired (S402). On the other hand, when the printing process is completed, the controller 126 ends the calculation process for the integrated value Psum.

<Driving amount of carriage motor>
In the case where the carriage motor 42 is driven between the driving operations of the transport motor 15, in addition to the above-described printing operation, flushing for discharging ink from the nozzles in order to eliminate clogging of the nozzles of the head 21. May be executed, or nozzle suction for sucking out ink from the nozzles may be executed. When performing these operations, the carriage 41 must move to a predetermined position such as the pump device 31 and the carriage motor 42 is driven.
When these operations are executed, the carriage motor 42 is driven twice or more during the drive stop period of the transport motor 15. That is, the carriage motor 42 repeats driving and stopping twice or more during the driving stop period of the transport motor 15.

  As described above, when the carriage motor 42 repeats driving and stopping at least twice, the total driving amount of the carriage motor 42 is preferable as the driving amount of the carriage motor 42 that is referred to by the controller 126 to obtain the subtraction value Psub. However, in order for the transport motor 15 to enter the heat generation restriction control at an early stage, the controller 126 may acquire any one drive amount as the drive amount of the carriage motor 42.

FIG. 22 illustrates an example of a drive situation when the carriage motor 42 is driven a plurality of times during the drive stop period of the transport motor 15. Here, the carriage motor 42 is driven twice during the drive stop period of the transport motor 15.
There are two timings when the drive amount of the carriage motor 42 is acquired by the controller 126 during the drive stop period of the transport motor 15. That is, there is once each before the carriage motor 42 is driven. Here, the drive amount of the carriage motor 42 that is referred to by the controller 126 to obtain the subtraction value Psub may be any one drive amount. That is, the driving amount at the first driving may be used, or the driving amount at the second driving may be used.

=== Subtraction value Psub ===
The subtraction value Psub to be subtracted from the integrated value Psum may be any value as long as it is a value corresponding to the drive amount of the carriage motor 42. However, in the present embodiment, in order to subtract the subtraction value Psub as appropriate as possible from the integrated value Psum, in addition to the drive amount of the carriage motor 42, the drive mode of the transport motor 15 is also considered. The subtraction value Psub corresponding to is subtracted from the integrated value Psum.

  FIG. 23 shows an example of a table referred to by the controller 126 for acquiring the subtraction value Psub. This table is a table showing the subtraction value Psub set according to the drive amount of the carriage motor 42 and the drive mode of the transport motor 15.

  The subtraction value Psub is divided into three according to the drive amount CRm of the carriage motor 42. That is, the drive amount CRm of the carriage motor 42 is “less than 1114 (step)”, “1114 (step) or more, less than 1894 (step)”, and “1894 (step) or more”. There are three. In the present embodiment, the drive amount of the carriage motor 42 is managed at 180 (dpi), and is “1/180 inch” per 1 (step).

  Here, the case where the drive amount CRm of the carriage motor 42 is “less than 1114 (step)” corresponds to, for example, the case where the stop time Tm of the transport motor 15 is “less than 100 [ms]”. Further, the case where the drive amount CRm of the carriage motor 42 is “1114 (step) or more and less than 1894 (step)” corresponds to, for example, a case where printing is performed on a sheet of “postcard” size, and the like. This corresponds to a case where the stop time Tm is “100 [ms] or more and less than 140 [ms]”. The case where the drive amount CRm of the carriage motor 42 is “1894 (step) or more” corresponds to, for example, the case where printing is performed on a sheet of about “A4” size, and the stop time Tm of the transport motor 15 is This corresponds to the case of “140 [ms] or more”.

  The subtraction value Psub is set to a different value for each drive amount CRm of the carriage motor 42. Further, here, the subtraction value Psub is set to a different value for each drive mode of the transport motor 15. There are seven drive modes, “PS0” to “PS6”. Each drive mode “PS0” to “PS6” is set according to the drive amount PFstep when the transport motor 15 is driven. Here, when the drive amount PFstep of the carry motor 15 is “1 to 25 (step)”, “PS6” is set as the drive mode of the carry motor 15. When the drive amount PFstep of the carry motor 15 is “25 to 50 (step)”, “PS5” is set as the drive mode of the carry motor 15. When the drive amount PFstep of the carry motor 15 is “50 to 100 (step)”, “PS4” is set as the drive mode of the carry motor 15. When the driving amount PFstep of the carry motor 15 is “100 to 150 (step)”, “PS3” is set as the drive mode of the carry motor 15. When the drive amount PFstep of the carry motor 15 is “150 to 200 (step)”, “PS2” is set as the drive mode of the carry motor 15. When the driving amount PFstep of the carry motor 15 is “200 to 250 (step)”, “PS1” is set as the drive mode of the carry motor 15. When the driving amount PFstep of the carry motor 15 is “250 (step) or more”, “PS0” is set as the drive mode of the carry motor 15.

<Drive mode>
The drive modes “PS0” to “PS6” have different control profiles for the transport motor 15 when the transport motor 15 is driven. FIG. 24 shows an example of a control profile for each drive mode “PS0” to “PS6”. Each of the drive modes “PS0” to “PS6” is different in at least one of acceleration during acceleration, speed at constant speed, and acceleration at deceleration when the transport motor 15 is driven.

  In the case of the drive mode “PS0”, the drive amount PFstep is very large as “250 (steps) or more”. Therefore, as shown in the upper left of FIG. At the time of acceleration, a large drive current is applied to the transport motor 15 and the speed of the transport motor 15 is controlled to reach the high speed range in a short time. Further, at the time of deceleration, in order to be able to stop in a short time from the high speed range, a reverse drive current is applied to control so as to rapidly decelerate.

On the other hand, in the drive mode “PS1”, the drive amount PFstep is “200 to 250 (step)”, which is slightly smaller than that in the case of “PS0”. In addition, the drive current of the transport motor 15 is small.
Similarly, in the drive mode “PS2”, since the drive amount PFstep is reduced to “150 to 200 (step)”, the set drive speed is also reduced and the drive current is also reduced.
Further, similarly, in the other drive modes “PS3” to “PS6”, the drive amount PFstep is gradually decreased, so that the set drive speed is gradually decreased and the drive current is also gradually decreased.

<Reason why subtraction value Psub is different>
The reason why the subtraction value Psub is thus different for each drive mode is as follows. FIG. 25 is a graph in which the number of sheets of paper that can be printed before the transport motor 15 reaches the limit temperature (hereinafter referred to as the limit temperature reached number) is examined by performing a simulation for each of the drive modes PS0 to PS6. . FIG. 25A summarizes the drive modes PS0, PS1, PS2, and PS3. FIG. 25B summarizes the drive modes PS3, PS4, PS5, and PS6. Note that, here, the limit temperature reaching number is converted and expressed when printing on A4 size paper. Further, as described above, the limit temperature reaching number can be obtained from the printing time of the transport motor 15 until reaching the limit temperature (limit temperature) at which the transport motor 15 can be safely used. Further, in order to facilitate comparison between the drive modes PS0 to PS6, the results in the case of the drive motor PS3 are shown in both FIG. 25A and FIG. 25B, respectively.

  In the drive modes PS0, PS1, PS2, and PS3, as shown in FIG. 25A, as the stop time of the transport motor 15 becomes longer, the number of sheets reaching the limit temperature increases. On the other hand, between the drive modes PS0 to PS3, the number of limit temperature reaching in the drive mode PS0 is the largest, and the number of limit temperature reaching in the drive mode PS3 is the smallest. This is presumably because the driving modes PS0, PS1, and PS2 have a higher driving speed than the driving mode PS3, and thus the number of sheets that can be printed before reaching the limit temperature is increased.

  On the other hand, in the drive modes PS3, PS4, PS5, and PS6, as shown in FIG. 25B, as in the case of the drive modes PS0, PS1, and PS2, as the stop time of the transport motor 15 becomes longer, the limit temperature is reached The number is increasing. However, between each of the drive modes PS3 to PS6, the number of limit temperature reaching in the drive mode PS6 is the largest, and the number of limit temperature reaching in the drive mode PS3 is the smallest. This is because, in the drive modes PS4, PS5, and PS6, the number of times the transport motor 15 is stopped is increased by the amount of the single drive amount PFstep, so that the number of sheets that can be printed before reaching the limit temperature is increased. It is thought that it is increasing.

Also, the drive mode PS4, PS5, PS6 has a larger slope of the graph than the drive modes PS0, PS1, PS2, PS3. It can be considered that the number of times that the limit temperature has reached is increased as the number of times of stopping 15 increases, and as the stop time of the transport motor 15 becomes longer.
In this way, the limit temperature reaching number is different for each drive mode PS0 to PS6. In particular, when the driving amount PFstep is larger than that in the other driving modes, the limit temperature reaching number does not necessarily increase, and the subtraction value Psub needs to be set individually for each driving mode PS0 to PS6.

<How to find the subtraction value Psub>
Next, how to obtain the subtraction value Psub will be described in detail. FIG. 26 is an example in the case where the limit temperature reaching number is set for each drive mode CRm of the carriage motor 42 for each drive mode PS0 to PS6. Here, in order to ensure higher safety, the number of reached limit temperatures is set on the safe side, that is, on the side where the actual simulation result is smaller. Note that the method described above is used here for the method of obtaining the limit temperature reaching number.

  First, a reference driving condition is determined. Here, as shown in the figure, in the drive mode PS3, the limit temperature reaching number when the drive amount CRm of the carriage motor 42 is “CRm <1114 (step)” is the smallest as “100”. Each subtraction value Psub is obtained based on this driving condition.

Here, it is assumed that the subtraction value Psub is obtained when the drive amount CRm of the carriage motor 42 is “CRm <1114 (step)” in the drive mode PS0. The limit temperature reaching number is “480 (sheets)”. The driving amount PFstep of the transport motor 15 when printing one A4 sheet is 580 (mm), and this limit temperature reached number of sheets is converted into the total number of drive steps of the transport motor 15 as follows.
480 (sheets) x 580 (mm) /25.4 (inches) x 720 (dpi)
= 7899163 (step) ………… (1)
Here, the number of drive steps is converted on the assumption that printing is performed at a resolution of 720 (dpi).
On the other hand, when the driving amount CRm of the carriage motor 42 is “CRm <1114 (step)” in the reference driving mode PS3, the total number of driving steps of the transport motor 15 is obtained as follows.

100 (sheets) x 580 (mm) /25.4 (inch conversion) x 720 (dpi)
= 1644094 (step) ………… (2)
Note that the value of (2) is the predetermined value Pduty.
When the difference between the value of (1) and the value of (2) is obtained, 6247559 (step) is obtained. From this difference, the increase rate when the drive amount CRm of the carriage motor 42 is “CRm <1114 (step)” in the drive mode PS0 is 6247559/7891653, and an increase rate of 0.79 is obtained.
The increase rate 0.79 is multiplied by the minimum drive amount 250 (step) in the drive mode PS0. As a result, a value of 0.79 × 250 = 197 is obtained. The value thus obtained is set as a subtraction value Psub when the drive amount CRm of the carriage motor 42 is “CRm <1114 (step)” in the drive mode PS0 as shown in the Psub table of FIG.

In the drive mode PS2, the case where the drive amount CRm of the carriage motor 42 is “1894 (Step) ≦ CRm” will be considered. Since the limit temperature reaching number is “374 (sheets)”, the total number of driving steps of the transport motor 15 in this case is as follows.
374 (sheets) x 580 (mm) /25.4 (inches) x 720 (dpi)
= 61489913 (step) ………… (3)
The difference between the value of (3) and the reference value of (2) is 4504819 (step). If an increase rate is calculated | required from this difference, the increase rate of about 0.73 is obtained by 4504819/6148913. Multiplying this increase rate 0.73 and the minimum drive amount 150 (step) in the drive mode PS2 yields 0.73 × 150 = 109, and this value is shown in the Psub table of FIG. Is set as the subtraction value Psub when the drive amount CRm of the carriage motor 42 is “1894 (Step) ≦ CRm”.
In this way, the subtraction value Psub in the drive amount of each carriage motor 42 in each drive mode is obtained from the number of reached limit temperatures shown in FIG. 26, and the Psub table as shown in FIG. 23 is completed.

<Procedure for obtaining subtraction value Psub>
FIG. 27 is a flowchart illustrating an example of a procedure for acquiring the subtraction value Psub by the controller 126. In order to obtain the subtraction value Psub, the controller 126 first obtains the drive amount CRm of the carriage motor 42 (S402). Next, the controller 126 acquires information related to the drive mode of the transport motor 15 (S404). Here, the information regarding the drive mode acquired by the controller 126 is information regarding the drive mode of the transport motor 15 when the transport motor 15 starts to be driven after the stop time of the transport motor 15 ends. That is, for example, when the carriage motor 42 is driven at the drive mode PS4 after the carriage motor 42 is driven at the drive amount 1500 (step), it corresponds to the drive amount 1500 (step) of the carriage motor 42. Then, the drive mode PS4 is acquired by the controller 126.

  After acquiring information related to the drive mode of the transport motor 15 in this way, the controller 126 then refers to the Psub table (see FIG. 23) (S406). Here, based on the acquired drive amount of the carriage motor 42 and the acquired drive mode of the transport motor 15, the controller 126 acquires a subtraction value Psub corresponding to these from the Psub table (S408). Thereafter, the controller 126 ends the process of acquiring the subtraction value Psub.

  After completing the process in this manner, the controller 126 performs an operation of subtracting the acquired subtraction value Psub from the integrated value Psum as described above with reference to FIG. The controller 126 acquires the subtraction value Psub every time it acquires the drive amount of the carriage motor 42 and the information related to the drive mode of the transport motor 15.

<Effect of subtraction of subtraction value Psub>
FIG. 28 shows how the integrated value Psum increases in the conventional case and in the present embodiment. In the conventional case, since the integrated value Psum is simply obtained by sequentially integrating the driving amount PFstep of the transport motor 15, as shown in the figure, the integrated value Psum is in an overheated state when the number of printed sheets is small. It reaches the predetermined value Pduty, which is the determination criterion. For this reason, when the temperature of the conveyance motor 15 does not increase so much, it is determined that the conveyance motor 15 is in an overheated state, and heat generation restriction control may be started for the conveyance motor 15. As a result, an extra standby time is generated in the conveyance motor 15, and there is a case in which the printing time becomes long and the printing process is delayed.

  On the other hand, in the present embodiment, the subtraction value Psub is successively subtracted from the integrated value Psum every time the transport motor 15 is driven. For this reason, in the present embodiment, as shown in the figure, the time when the integrated value Psum reaches the predetermined value Pduty is delayed as compared with the conventional case. That is, the integrated value Psum does not reach the predetermined value Pduty unless the temperature of the transport motor 15 is sufficiently increased. Thus, in the case of the present embodiment, it is possible to perform printing for an extra N sheets before the execution of the heat generation restriction control, as compared with the conventional case.

<Summary>
As described above, in the ink jet printer 1 according to the present embodiment, in addition to the calculation of sequentially integrating the driving amount PFstep of the transport motor 15 to obtain the integrated value Psum, the subtraction value corresponding to the driving amount from the driving amount of the carriage motor 42. Since an operation for subtracting Psub from the integrated value Psum is executed, an integrated value Psum suitable for the temperature state of the transport motor 15 can be obtained. Accordingly, it is determined that the conveyance motor 15 is in an overheated state even though the conveyance motor 15 is not in an overheated state, and the heat generation restriction control is prevented from being executed at an early stage on the conveyance motor 15. Can do. Further, even with a small size motor, it is possible to secure the same number of sheets reaching the heat generation limit temperature, and the cost can be reduced.

  Furthermore, in the present embodiment, the subtraction value Psub subtracted from the integrated value Psum is set in consideration of the drive mode of the transport motor 15, so that a more appropriate subtracted value Psub can be subtracted from the integrated value Psum. Thus, the integrated value Psum that matches the temperature state of the transport motor 15 can be obtained.

  In this embodiment, the driving amount PFstep of the transport motor 15 is added to the integrated value Psum before the transport motor 15 is driven based on the drive amount PFstep. The heat generation restriction control can be executed at an early stage for the transport motor 15. Thereby, safety can be improved more.

  In the present embodiment, since the Psub table in which the stop time and drive mode of the transport motor 15 are associated with the subtraction value Psub is provided, the subtraction value Psub can be easily obtained.

  In the present embodiment, the case where the conveyance motor 15 is used as the motor for determining the overheat state has been described as an example. However, in the case of the inkjet printer 1 according to the present embodiment, the carriage motor 42 is also in the overheat state. It is also possible to determine whether or not In this case, various operations and information acquisition are performed by the controller 126. In this case, the subtraction value corresponding to the drive amount of the carry motor 15 may be acquired using the carry motor 15 as the “other motor” of the present invention. Of course, the heat generation restriction control may also be executed for the carriage motor 42.

=== Other Embodiments ===
As described above, the case where the motor overheating determination device according to the present invention is installed in the printing apparatus (inkjet printer 1) has been described as an example based on the embodiment. However, the present invention is not intended to be interpreted in a limited manner. The present invention can be changed or improved without departing from the gist thereof, and needless to say, the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.
In the present embodiment, part or all of the configuration realized by hardware may be replaced by software, and conversely, part of the configuration realized by software may be replaced by hardware.
In addition, a part of the processing performed on the printing device side may be performed on the computer 140 side, and a dedicated processing device is provided between the printing device and the computer 140 to perform processing on this processing device. You may make it perform a part.

<About printing devices>
In the embodiment described above, the case of the ink jet printer 1 as described above has been described as an example of the printing apparatus in which the motor overheat determination device according to the present invention is mounted. However, the motor overheat determination device according to the present invention is described. Is not limited to such a printing apparatus, but is an ink jet printer that ejects ink by other methods, or other types of printers that do not eject ink, such as dot impact printers, thermal transfer printers, Any apparatus that has a printing function, such as a laser beam printer, is included in the printing apparatus of the present invention.

<About the motor to be judged>
In the above-described embodiment, the motor (conveyance motor 15) mounted on the above-described printing apparatus has been described as an example of the motor that performs the overheat determination. However, the motor that is a determination target in the present invention is not necessarily in this manner. It is not limited to a motor mounted on a simple printing apparatus. In other words, any motor mounted on a device other than the printing device can be an object of overheat determination in the present invention.

<About other motors>
In the embodiment described above, the “other motor” of the present invention has been described by taking the motor (carriage motor 42) mounted on the printing apparatus as an example. However, the motor to be determined in the present invention is not necessarily limited to this. It is not limited to the motor mounted on such a printing apparatus. Any motor may be used as long as it is a motor driven alternately with a motor corresponding to the “determination target motor” of the present invention (the conveyance motor 15 in the above-described embodiment).

<About overheat determination device>
In the embodiment described above, the case where the motor overheat determination device according to the present invention is provided in an apparatus equipped with a motor such as a printing device has been described as an example. However, this is not necessarily the case. That is, the motor overheat determination device according to the present invention may exist as a single device independent of the device including the motor, or may be present as a single device independent of the motor.

<About the motor drive amount>
In the above-described embodiment, the case where the motor driving amount is represented by the number of steps (number of steps) has been described as an example. However, the present invention is not necessarily limited to such a case, and other units, For example, it may be expressed by a unit such as millimeter (mm), centimeter (cm), or micrometer (μm).

<About the information acquisition unit>
In the above-described embodiment, the controller 126 or the like is exemplified as the information acquisition unit of the present invention. However, in the present invention, the present invention is not necessarily limited to such a case, and information related to information related to the drive amount of the motor is provided. Any information acquisition unit may be used as long as it is acquired. For example, a communication interface that performs data communication with the outside may be included in the information acquisition unit of the present invention.

<About the calculation unit>
In the above-described embodiment, the controller 126 is exemplified as the calculation unit of the present invention. However, the present invention is not limited to such a case, and the calculation for calculating the integrated value of the motor drive amount is not necessarily performed. In addition, any calculation unit that can execute a calculation for subtracting a subtraction value from an integrated value is included in the calculation unit of the present invention.

<Subtraction value according to the drive amount of other motors>
In the above-described embodiment, as the “subtraction value according to the driving amount of another motor” (Psub) of the present invention, the driving amount of the carriage motor 42 is “less than 1114 (step)” and “1114 ( step) or more, less than 1894 (step) ”and“ 1894 (step) or more ”, and the case where it is divided into three cases has been described as an example. However, in the present invention, this is not necessarily the case. For example, a subtraction value that is appropriately increased or decreased according to a change in the drive amount of the carriage motor 42 may be set.

<About the predetermined value>
In the above-described embodiment, as the predetermined value of the present invention, the driving amount of the motor when the motor (conveyance motor 15) is driven under the most severe condition (worst condition) is set as the predetermined value Pduty. In the present invention, the present invention is not necessarily limited to such a case. For example, the value may be set to a value smaller than the value when driven under the harshest conditions.
Further, the predetermined value of the present invention is not necessarily set to be fixed as in the above-described embodiment. That is, for example, in the case of the printing apparatus described above, the predetermined value Pduty may vary according to the printing conditions, the printing method, and the like. In addition, the predetermined value (Pduty) may be appropriately changed according to various conditions.

<About drive mode>
In the above-described embodiment, as the drive mode of the present invention, at least one of acceleration at the time of acceleration of the motor, speed at constant speed, and acceleration at deceleration according to the drive amount of the motor (conveyance motor 15). Although one different driving mode has been described, the driving mode of the present invention is not limited to such a case. That is, different driving modes may be used depending on various factors such as a driving method. Further, different drive modes may be used depending on printing conditions, printing conditions, and the like.
It is very effective to set the subtraction value Psub for each drive mode, especially when the number of sheets of paper that can be printed before reaching the temperature at which the motor can be used safely and the limit temperature differs depending on the drive mode. To work.

<About motor control device>
In the embodiment described above, the controller 126 and the conveyance control unit 130 provided in the printing apparatus (inkjet printer 1) are described as examples of the motor control apparatus. However, in the present invention, this is not necessarily the case. However, the present invention is not limited to this, and may be configured in other forms. The motor control method is not limited to the control method described above.

<About media>
The medium S includes plain paper, matte paper, cut paper, glossy paper, roll paper, paper, photographic paper, roll-type photographic paper, etc. In addition to these, film materials and cloth materials such as OHP film and glossy film Alternatively, a metal plate material or the like may be used. That is, any medium can be used as long as it can be an ink ejection target.

1 is a perspective view of an embodiment of a printing apparatus according to the present invention. FIG. 3 is a perspective view illustrating an internal configuration of the printing apparatus. Sectional drawing which shows the conveyance part of a printing apparatus. 1 is a block configuration diagram showing a system configuration of a printing apparatus. FIG. 3 is a plan view illustrating an example of a head of a printing apparatus. 6 is a flowchart for explaining an example of printing processing. Explanatory drawing explaining an example of the rotary encoder. The block diagram which shows the structure of the detection part of a rotary encoder. FIG. 9A is a timing chart showing the output waveform of the linear encoder during forward rotation, and FIG. 9B is a timing chart showing the output waveform of the linear encoder during reverse rotation. The block block diagram of a conveyance control part. FIG. 11A is a graph of the time change of the duty signal input to the PWM circuit, and FIG. 11B is a graph of the speed change of the motor. The block block diagram of a carriage control part. The figure explaining the example of control based on overheating determination of a conveyance motor. The figure which showed an example of the integration | accumulation by a controller. FIG. 15A is a diagram illustrating a driving state of the conveyance motor at a normal time, and FIG. 15B is a diagram illustrating a driving state of the conveyance motor when heat generation is limited. The flowchart explaining an example of the process sequence of an integrating | accumulating process and a determination process. Explanatory drawing for demonstrating an example of the setting method of predetermined value Pduty. Explanatory drawing for demonstrating the outline | summary of the main processes of this embodiment. The flowchart explaining an example of the process sequence of a subtraction process. Explanatory drawing for demonstrating the outline | summary of another process example. The flowchart explaining an example of the procedure of the calculation process in another process example. The figure explaining an example of the drive condition in case another motor is driven in multiple times during the drive stop period of the motor for judgment. The figure which shows an example of the table for acquiring the subtraction value Psub. The figure explaining an example of the profile for control according to drive mode. FIG. 25A shows the number of reaching the limit temperature in the driving modes PS0, PS1, PS2, and PS3, and FIG. 25B shows the number of reaching the limit temperature in the driving modes PS3, PS4, PS5, and PS6. The table | surface which shows the limit temperature reach | attainment number according to the drive mode and stop time of a motor. The flowchart explaining an example of the acquisition procedure of a subtraction value. The figure explaining the difference in the increase method of the integrated value in the past and this embodiment.

Explanation of symbols

1 Inkjet printer, 2 operation panel, 3 paper discharge unit, 4 paper supply unit,
5 operation buttons, 6 indicator lamps, 7 paper discharge tray, 8 paper feed tray,
11A paper insertion slot, 11B roll paper insertion slot, 13 paper feed roller, 14 platen,
15 Conveyance motor, 17A Conveyance roller, 17B Discharge roller,
18A free roller, 18B free roller, 21 heads,
30 cleaning unit, 31 pump device, 35 capping device,
41 Carriage, 42 Carriage motor, 44 Pulley, 45 Timing belt,
46 guide rail, 48 ink cartridge, 49 cartridge mounting part,
51 linear encoder, 53 paper detection sensor, 122 buffer memory,
124 image buffer, 126 controller, 127 main memory,
128 Carriage motor controller, 129 EEPROM, 130 Transport controller,
132 head drive unit, 134 rotary encoder, 140 computer,
211Y nozzle group, 211C nozzle group, 211M nozzle group, 211K nozzle group,
331 Position calculation unit, 332 subtractor, 333 gain, 334 speed calculation unit,
335 subtractor, 336A proportional element, 336B integral element, 336C differential element,
337 Adder, 338 PWM circuit, 339A acceleration control unit, 339B timer,
340 driver, 402 rotary encoder code plate, 404 detector,
406 slit, 408 large gear, 410 small gear, 412 light emitting diode,
414 collimator lens, 416 detection processing unit, 418 photodiode,
420 signal processing circuit, 422A comparator, 422B comparator,
431 Position calculation unit, 432 subtractor, 433 gain, 434 speed calculation unit,
435 subtractor, 436A proportional element, 436B integral element, 436C differential element,
437 adder, 438 PWM circuit, 439A acceleration control unit, 439B timer,
440 driver, 511 linear encoder code plate, S medium

Claims (15)

An information acquisition unit for acquiring information on a driving amount of a determination target motor and information on a driving amount of another motor driven alternately with the determination target motor;
An operation for calculating an integrated value by sequentially integrating the driving amount of the determination target motor based on information regarding the driving amount of the determination target motor acquired by the information acquisition unit, and the other information acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the determination target motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
An overheat determination device for a motor, comprising:   The motor overheat determination device according to claim 1, wherein the information regarding the drive amount of the determination target motor is acquired by the information acquisition unit every time the determination target motor is driven.   3. The motor according to claim 1, wherein the information on the driving amount of the determination target motor is acquired by the information acquisition unit before the determination target motor is driven based on the driving amount. Overheat judgment device.   4. The calculation unit according to claim 1, wherein the calculation unit performs a calculation of subtracting a predetermined value from the integrated value every time a predetermined time elapses after driving of the determination target motor is stopped. The overheat determination device for a motor according to item 1.   5. The driving of the determination target motor is limited when the determination target motor is determined to be in an overheated state by the determination unit. 6. Motor overheat determination device.   The motor overheat determination device according to any one of claims 1 to 5, further comprising a table in which the driving amount of the other motor and the subtraction value are associated with each other. The information acquisition unit acquires information on a driving mode of the determination target motor,
The said subtraction value is acquired based on the information regarding the said drive mode which the said information acquisition part acquired, and the information regarding the drive amount of the said other motor, The any one of Claims 1-6 characterized by the above-mentioned. Motor overheat determination device.   The motor according to claim 7, wherein the determination target motor has at least one of acceleration at acceleration, speed at constant speed, and acceleration at deceleration depending on the drive mode. Overheat judgment device. An information acquisition unit for acquiring information on a driving amount of a determination target motor and information on a driving amount of another motor driven alternately with the determination target motor;
An operation for calculating an integrated value by sequentially integrating the driving amount of the determination target motor based on information regarding the driving amount of the determination target motor acquired by the information acquisition unit, and the other information acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the determination target motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
Information on the driving amount of the determination target motor is acquired by the information acquisition unit every time the determination target motor is driven, and is acquired by the information acquisition unit before the motor is driven based on the driving amount. And
The calculation unit performs a calculation of subtracting a predetermined value from the integrated value every time a predetermined time has elapsed after the driving of the determination target motor is stopped,
When the determination target motor is determined to be in an overheated state by the determination unit, driving of the determination target motor is limited,
A table in which the driving amount of the other motor is associated with the subtraction value;
The information acquisition unit acquires information on the drive mode of the motor,
The subtraction value is acquired based on information on the drive mode acquired by the information acquisition unit and information on the drive amount of the other motor,
The motor determination apparatus according to claim 1, wherein the determination target motor has at least one of acceleration at acceleration, speed at constant speed, and acceleration at deceleration according to the drive mode. Obtaining information on the driving amount of the motor to be determined;
Obtaining information relating to the drive amount of another motor driven alternately with the determination target motor;
Calculating the integrated value by sequentially integrating the drive amount of the determination target motor based on the acquired information on the drive amount of the determination target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the determination target motor is in an overheated state when the subtracted integrated value reaches a predetermined value;
A method for determining overheating of a motor, comprising: Obtaining information on the driving amount of the motor to be determined;
Obtaining information relating to the drive amount of another motor driven alternately with the determination target motor;
Calculating the integrated value by sequentially integrating the drive amount of the determination target motor based on the acquired information on the drive amount of the determination target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the determination target motor is in an overheated state when the subtracted integrated value reaches a predetermined value;
A motor overheating determination program characterized by executing An information acquisition unit that acquires information on the drive amount of the motor to be controlled and information on the drive amount of another motor that is driven alternately with the motor to be controlled;
An operation for calculating the integrated value by sequentially integrating the drive amount of the motor to be controlled based on the information on the drive amount of the motor to be controlled acquired by the information acquisition unit, and the other acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on information on the driving amount of the motor from the integrated value;
A determination unit that determines that the motor to be controlled is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
A controller that controls the drive of the control target motor and controls the drive of the control target motor when the determination unit determines that the control target motor is in an overheated state;
A motor control device comprising: Obtaining information on the drive amount of the motor to be controlled;
Obtaining information relating to the drive amount of another motor driven alternately with the motor to be controlled;
Calculating the integrated value by sequentially integrating the drive amount of the control target motor based on the acquired information on the drive amount of the control target motor;
Subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the acquired information on the driving amount of the other motor from the integrated value;
Determining that the motor to be controlled is in an overheated state when the subtracted integrated value reaches a predetermined value;
Limiting the drive of the control target motor when it is determined that the control target motor is in an overheat state; and
A motor control method characterized by comprising: A printing section for printing on the medium;
Two motors driven alternately,
An information acquisition unit for acquiring information related to the drive amount of the motor;
Based on information about the driving amount of one motor acquired by the information acquisition unit, an operation for calculating the integrated value by sequentially integrating the driving amount of the one motor, and the driving amount of the other motor acquired by the information acquisition unit An arithmetic unit that performs an operation of subtracting a subtraction value corresponding to the driving amount of the other motor acquired based on the information on the integrated value from the integrated value;
A determination unit that determines that the one motor is in an overheated state when the integrated value subtracted by the calculation unit reaches a predetermined value;
A printing apparatus comprising: The motor is a motor for conveying a medium to be printed by the printing unit, and a motor for moving a printing unit that performs printing on the medium relative to the medium. The printing apparatus according to claim 14.

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