JP2006255899A - Recording apparatus and method for controlling motor in recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To exactly tackle a problem caused by change of temperature of a timing belt in a recording apparatus having a system to be driven by a motor and transmitting the power of the motor to the system to be driven by the timing belt. <P>SOLUTION: In a printer having a constitution for transmitting the power of a paper feeding motor 60 to a carrying mechanism part 30B through the timing belt 62, when a recording operation for recording an image on a recording paper 20 is executed, the temperature of the paper feeding motor 60 is detected by a temperature detecting part 69, and based on the temperature detected and an initial load of the paper feeding motor 60, a constant used for controlling the paper feeding motor 60 is established. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording apparatus including a motor and a motor control method in the recording apparatus.

In general, in a recording apparatus that records an image on a recording medium, a conveying mechanism that performs a conveying operation (so-called paper feeding) of the recording medium includes a conveying motor as a power source, a plurality of conveying rollers that contact the recording medium, and a conveying motor. A gear for transmitting the driving force to the conveying roller. As a method for controlling the transport motor, an example is known in which the driving load of the motor is measured in advance, and control according to the driving load obtained by this measurement is performed (see, for example, Patent Document 1).
JP 2003-23783 A

  Recently, a mechanism for transmitting the power of the transport motor to the transport roller via a timing belt has been adopted in the transport mechanism. The timing belt is preferably made of a material containing glass fiber in terms of strength and durability. However, timing belts containing glass fibers have the property of shrinking as their temperature increases. Therefore, during the operation of the recording apparatus, the timing belt is heated by the heat generated by the friction of the timing belt or the heat transmitted from the transport motor, and the timing belt contracts, and the load applied to the transport motor may increase. In this case, as the temperature of the timing belt rises, there is a difference between the drive load measured in advance and the drive load actually applied to the transport motor, so there is a concern that the accuracy of the transport operation may decrease. The For this reason, conventionally, when there is a possibility that the temperature of the timing belt or the conveyance motor may exceed a predetermined temperature, the reduction of accuracy is avoided by restricting the operation of the conveyance motor. It will decline. Therefore, in order to realize a higher-speed and higher-precision recording apparatus, a method for responding to changes in the timing belt without limiting the operation of the transport motor has been required.

  SUMMARY OF THE INVENTION Accordingly, the present invention provides a recording apparatus having a driven system driven by a motor and transmitting the power of the motor to the driven system by a timing belt so as to accurately cope with a temperature change of the timing belt. With the goal.

  In order to solve the above-described problems, the present invention includes a motor, a timing belt that transmits the power of the motor to a driven system, and a control unit that performs arithmetic processing using parameters to control the operation of the motor. In the recording apparatus that performs a recording operation for recording an image on a recording medium, the recording apparatus includes a temperature detecting unit that detects the temperature of the timing belt or a temperature correlated with the temperature of the timing belt, and the control unit includes the recording unit In executing the operation, the parameter is set based on a temperature detected by the temperature detecting means and an initial driving load of the motor.

  According to the present invention, a motor, a timing belt that transmits the power of the motor to a driven system, and a control unit that performs arithmetic processing using parameters to control the operation of the motor are provided, and an image is recorded on a recording medium. When performing a recording operation in a recording apparatus that performs a recording operation, the temperature of the timing belt or a temperature correlated with the temperature of the timing belt is detected, and the detected temperature and the initial driving load of the motor are detected. Since the parameters are set based on this, even when recording is performed on a large number of recording media, even if the timing belt changes due to the temperature change of the timing belt, the optimum parameters are set taking this change into account. Therefore, it is possible to control the motor accurately without limiting the operation of the motor to reduce the throughput. The stomach operation accuracy can be maintained.

  In the present invention, the control means controls the operation of the motor by a method including PID (Proportional, Integral, Differential) control, and the parameters include a proportional term constant and an integral term constant in the PID control. And a differential term constant.

  In this case, the control means sets the proportional term constant, the integral term constant, and the derivative term constant when performing the PID control related to the operation of the motor, the temperature that correlates with the temperature of the timing belt or the temperature of the timing belt, and the initial value. Since the setting is based on the driving load, even if the state of the timing belt changes due to the temperature change of the timing belt, the motor can be accurately controlled by setting the optimum parameters taking this change into account.

  In the present invention, the control means includes storage means for storing the parameters in association with the temperature range of the timing belt and the initial driving load, and the temperature detection is performed when the recording operation is performed. The parameter stored in the storage means may be read and set based on the temperature range corresponding to the temperature detected by the means and the initial driving load.

  In this case, when executing the recording operation, the control means uses the parameters stored in association with the temperature range of the timing belt and the initial drive load as the temperature range corresponding to the temperature detected by the temperature detection means and the initial value. Since the data is read and set based on the driving load, a recording apparatus that can cope with a change in the state of the timing belt caused by a change in the temperature of the timing belt can be easily realized with a simple configuration. In addition, the operation related to the parameter setting can be performed at high speed.

  Further, in the present invention, the control means sets the parameter based on the temperature detected by the temperature detection means and the initial driving load each time a page break operation is performed during execution of the recording operation. It is good.

  In this case, the control unit sets the parameter based on the temperature detected by the temperature detection unit and the initial driving load every time a page break operation is performed during the execution of the recording operation. Has the advantage that the parameters are not changed and the recording quality within the page is kept uniform. Furthermore, since the frequency of setting the parameters is moderately low, there is an advantage that throughput is not reduced while responding to a change in the state of the timing belt due to a change in the temperature of the timing belt.

  In the present invention, the control unit sets the parameter based on the temperature detected by the temperature detection unit and the initial driving load every time a line feed operation is performed during execution of the recording operation. Also good.

  In this case, the control unit sets the parameter based on the temperature detected by the temperature detection unit and the initial driving load every time a line feed operation is performed during the execution of the recording operation. Thus, it is possible to quickly cope with a change in the state of the timing belt caused by a change in the temperature of the timing belt.

  Furthermore, in the present invention, the temperature detecting means may detect the temperature of the motor as a temperature having a correlation with the temperature of the timing belt.

  In this case, since the temperature detection means detects the temperature of the motor as a temperature having a correlation with the temperature of the timing belt, a recording device that can cope with the timing belt state change caused by the temperature change of the timing belt has a simple configuration. Can be easily realized.

  The present invention provides a motor control method for controlling operation of a motor by performing arithmetic processing using parameters in a recording apparatus including a motor and a timing belt that transmits the power of the motor to a driven system. When performing the recording operation, the temperature of the timing belt or a temperature correlated with the temperature of the timing belt is detected, and the parameter is determined based on the detected temperature and the initial driving load of the motor. Is set.

  According to the present invention, a motor, a timing belt that transmits the power of the motor to a driven system, and a control unit that performs arithmetic processing using parameters to control the operation of the motor are provided, and an image is recorded on a recording medium. When performing a recording operation in a recording apparatus that performs a recording operation, the temperature of the timing belt or a temperature correlated with the temperature of the timing belt is detected, and the detected temperature and the initial driving load of the motor are detected. Since the parameters are set based on the timing belt, even if the timing belt changes due to the temperature change of the timing belt, it is possible to accurately control the motor by setting the optimal parameters that take this change into account. It is possible to operate with.

  According to the present invention, when performing the recording operation, the temperature of the timing belt or the temperature having a correlation with the temperature of the timing belt is detected, and the parameter is set based on the detected temperature and the initial driving load of the motor. Therefore, even if the timing belt changes due to the temperature change of the timing belt, the motor can be accurately controlled by setting the optimal parameters that take this change into account, and the throughput is reduced. It is possible to operate with high accuracy without causing it.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an external perspective view showing the configuration of a printer 10 according to an embodiment of the present invention, and particularly shows the configuration of the exterior of the printer 10. A printer 10 shown in FIG. 1 is configured by housing a main body including a recording mechanism unit 30A (FIG. 2) and a conveyance mechanism unit 30B (FIG. 3), which will be described later, in a case 11 as an exterior, and recording is performed by the conveyance mechanism unit 30B. An image including characters is recorded by ejecting ink onto the recording surface of the recording paper 20 from the recording head 32 (FIG. 2) of the recording operation system 30B while conveying the paper 20.
In the printer 10, a recording medium made of paper or synthetic resin (specifically, specially processed paper such as plain paper or coated paper, or glue is applied or attached to the back surface as a recording medium on which an image is to be recorded. A sealing sheet, a transparent or opaque synthetic resin sheet, etc.) can be used. The size and shape of the recording medium are not particularly limited, and may be, for example, a cut sheet, an envelope, a bag, or the like, or a sheet whose size and shape are processed after image recording (for example, It is also possible to use a sheet having a perforation or a cut so that it can be divided into a plurality of sheets. In this embodiment, a case where a recording paper 20 made of rectangular plain paper is used as a recording medium will be described as an example.

  An upper cover 12 that can be opened upward is disposed on the upper surface of the case 11, and the upper cover 12 can be opened to perform maintenance such as replacement of an ink cartridge 34 (FIG. 2) described later. Yes. A paper feed tray 13 is disposed at the rear end of the case 11. The paper feed tray 13 can set a plurality of recording papers 20 to be recorded in a stacked manner. In addition, on the front surface of the case 11, a paper discharge port 14 through which the recording paper 20 on which an image has been recorded is discharged is provided. A stand or the like for receiving the discharged recording paper 20 may be provided below the paper discharge port 14.

FIG. 2 is a perspective view illustrating a configuration of the recording mechanism unit 30 </ b> A accommodated in the case 11. In FIG. 2, illustrations of portions other than the recording mechanism unit 30 </ b> A included in the main body of the printer 10 are omitted.
As shown in FIG. 2, the recording mechanism unit 30 </ b> A includes a carriage 33 configured to be movable along the width direction of the recording paper 20, a recording head 32 mounted on the carriage 33, and ink for the recording head 32. Ink cartridge 34, a carriage motor 35 disposed on one end side of the main body frame 31, a pulley 36A provided on a rotating shaft of the carriage motor 35, and a pulley 36B disposed on the other end side of the main body frame 31. A timing belt 37 that spans between the pulleys 36A and 36B and engages the carriage 33; a code plate 38 that extends along the direction of movement of the carriage 33 to detect the position of the carriage 33; Within a range where the platen 39 indicating the recording paper 20 and the carriage 33 can be moved just below the recording head 32. And a pump unit 40 and the capping device 41 is located outside of the recording sheet 20.

The recording head 32 includes a plurality of nozzles (not shown) facing the recording surface of the recording paper 20 positioned below the recording head 32, and reciprocally moves along the width direction of the recording paper 20 together with the carriage 33. An image is recorded on the recording surface of the recording paper 20 by ejecting ink supplied from the ink cartridge 34 from the nozzles. The carriage 33 on which the recording head 32 is mounted is moved along the width direction (main scanning direction) of the recording paper 20 by driving the timing belt 37 by the operation of the carriage motor 35. Accordingly, the moving direction of the carriage 33 is determined by the rotating direction of the carriage motor 35. Further, a slit is formed in the code plate 38 extending along the main scanning direction of the carriage 33 every predetermined length (for example, 1/180 inch), and the slit is disposed at the end of the carriage 33. By detecting by the encoder 84 (FIG. 5), the position of the carriage 33 in the width direction is detected.
The capping device 41 seals the nozzle exposed on the front end surface of the recording head 32 with a cap 42 when the recording head 32 is not performing a recording operation. The pump unit 40 applies a negative pressure to the nozzles of the recording head 32 sealed by the cap 42 when the nozzles of the recording head 32 are clogged by the operation of the built-in pump motor 87 (FIG. 5). The ink is forcibly ejected from the recording head 32.

FIG. 3 is a perspective view illustrating a configuration of the transport mechanism unit 30 </ b> B accommodated in the case 11. FIG. 4 is an enlarged view of a main part of FIG. In FIGS. 3 and 4, portions other than the conveyance mechanism unit 30 </ b> B included in the main body of the printer 10 are not illustrated.
The transport mechanism 30B as the driven system of the present invention is driven by a paper feed motor 60 corresponding to the motor of the present invention, and takes in the recording paper 20 placed on the paper feed tray 13 (FIG. 1) one by one. A series of operations are performed in which the printer 10 is transported and discharged from the paper discharge port 14 (FIG. 1). The transport mechanism unit 30B includes a paper feed roller 51, a paper feed roller 53, a driven roller 54, a paper discharge roller 56, and a knurled roller 58 for transporting the recording paper 20 from the paper feed tray 13 to the paper discharge port 14. A pulley 61, a timing belt 62, a paper discharge gear 63, a transmission wheel 64, a large gear 65, and a paper feed gear 66 are provided for transmitting the power of the paper feed motor 60 to these rollers. The transport mechanism unit 30 </ b> B includes a code plate 67 and an encoder 68 for detecting the rotation state of the paper feed motor 60.

  The paper feed roller 51 is composed of a plurality of rollers inserted through the paper feed roller shaft 52, and rotates in contact with the recording paper 20 on the paper feed tray 13 from the upper surface, so that one sheet of recording paper is fed from the paper feed tray 13. 20 is taken in. The paper feed roller 53 is a cylindrical member that extends in the main scanning direction of the recording head 32, and rotates in contact with the recording paper 20 from below on the paper feed table 13 (FIG. 1) side from the recording head 32. The driven roller 54 faces the paper feed roller 53 through the recording paper 20 and rotates as the recording paper 20 moves. The driven roller 54 is rotatably supported at the tip of a holder 55 that suppresses the lifting of the recording paper 20, and is urged together with the holder 55 toward the recording paper 20. For this reason, the recording paper 20 taken in by the paper feed roller 51 rotates between the paper feed roller 53 and the driven roller 54. The paper discharge roller 56 includes a plurality of rollers inserted through the paper discharge roller shaft 57, and rotates in contact with the recording paper 20 from below on the paper discharge port 14 (FIG. 1) side from the recording head 32. A plurality of jagged rollers 58 arranged in the main scanning direction of the recording head 32 are opposed to the paper discharge roller 56, and the recording paper 20 is sandwiched and conveyed between the jagged roller 58 and the paper discharge roller 56, and is discharged from the paper discharge port. 14 is discharged.

A paper feed motor 60 that drives each of these rollers is disposed at the lower front side of the main body frame 31. The paper feed motor 60 is a DC motor that rotates according to the control of a DC unit 80 (FIG. 5) described later. A pulley 61 is disposed at the tip of the rotation shaft 60 </ b> A of the paper feed motor 60, and a timing belt 62 is bridged between the pulley 61 and the paper discharge gear 63 assembled to the paper discharge roller shaft 57. Yes. The timing belt 62 is a belt made of a material containing glass fiber, and has teeth that mesh with the pulley 61 and the paper discharge gear 63 inside.
Further, a transmission wheel 64 is disposed on the paper discharge roller shaft 57 coaxially with the paper discharge gear 63. A large gear 65 having the paper feed roller 53 as an axis is engaged with the transmission wheel 64. The large gear 65 further meshes with a paper feed gear 66 having the paper feed roller shaft 52 as an axis. With this configuration, when the paper feed motor 60 operates and the pulley 61 rotates, this rotational force is transmitted to the paper discharge roller shaft 57 via the timing belt 62 and the paper discharge gear 63, and the paper discharge roller 56 rotates. Further, the rotational force of the paper discharge gear 63 is transmitted to the paper feed roller 53 via the transmission wheel 64 and the large gear 65 to rotate the paper feed roller 53. Further, the sheet feeding roller 51 is rotated by the rotational force transmitted from the large gear 65 to the sheet feeding gear 66. As described above, the rollers included in the transport mechanism unit 30 </ b> B are simultaneously driven by the paper feed motor 60.

Further, the large gear 65 is provided with a disk-shaped code plate 67 having the paper feed roller 53 as an axis, like the large gear 65. A large number of slits are formed at a peripheral portion of the code plate 67 at a predetermined interval, and an encoder 68 is disposed so as to sandwich the peripheral portion of the code plate 67. The encoder 68 optically reads the slit of the code plate 67 and outputs a read signal to the control unit 70 (FIG. 5) described later. By detecting the slit of the code plate 67 by the encoder 68, it is possible to detect the rotation state of the large gear 65. Based on the rotation state of the large gear 65, the rotation of each roller that conveys the recording paper 20 is detected. The state can be detected.
On the side surface of the paper feed motor 60, a temperature detection unit 69 serving as a temperature detection unit is provided. The temperature detection unit 69 includes a substrate on which the thermistor is mounted, and is connected to the control unit 70 (FIG. 5), and is configured so that the control unit 70 can detect the resistance value of the thermistor.

FIG. 5 is a block diagram illustrating a functional configuration of the control unit 70 that controls the operation of each unit of the printer 10. As shown in FIG. 5, the control unit 70 includes a CPU (Central Processing Unit) 71 that controls each unit of the control unit 70, a timer IC (Integral Circuit) 72 that periodically outputs an interrupt signal to the CPU 71, and the printer 10. The IF unit 74 that transmits and receives various data including recording data that is image data to be recorded on the recording paper 20 with the host 73 connected to the outside, and the print resolution and recording based on the data received by the IF unit 74 ASIC (Application Specific Integrated Circuit) 75 for controlling the driving waveform of the head 32, CPU 71 and PROM (Programmable Read Only Memory) 76, RAM (Random Access Memory) used as a storage area and work area for programs executed by the ASIC 75 77 and EEPROM (Electronically Erasable and Programmable Read Only Memory) 78, and In addition, a DC unit 80 that controls the operation of various motors provided in the printer 10, a paper detection sensor 81 that detects the presence or absence of the recording paper 20 near the paper feed roller 51 (FIG. 3), and a paper feed that drives and controls the paper feed motor 60 A motor driver 82; a head driver 83 that controls the drive of the recording head 32; an encoder 84 that reads a slit of the code plate 38 disposed along the main scanning direction of the recording head 32 and outputs a read signal to the DC unit 80; Each unit includes a carriage motor driver 85 for driving and controlling the motor 35, a pump motor driver 86 for driving and controlling a pump motor 87 disposed in the pump unit 40 (FIG. 1), and the pump motor 87.
The DC unit 80 is connected to an encoder 68 that detects the slit of the code plate 67 (FIGS. 3 and 4) and a temperature detector 69 that detects the temperature of the paper feed motor 60 (FIGS. 3 and 4). Is done.

The DC unit 80 drives and controls the paper feed motor 60 based on the read signal input from the encoder 68 and the resistance value of the thermistor included in the temperature detection unit 69 in accordance with the control signal input from the CPU 71. Here, the drive control of the paper feed motor 60 by the DC unit 80 will be described in detail.
FIG. 6 is a block diagram showing the configuration of the DC unit 80 in detail. In FIG. 6, as a main element for generating a command signal for the paper feed motor driver 82, a rotational position calculation unit 801, a subtractor 802, a target rotation speed calculation unit 803, a rotation speed calculation unit 804, and a subtraction An 805, a proportional element 806 as a proportional means, an integral element 807 as an integral means, a differential element 808 as a differential means, an adder 809, a PWM circuit 810, a timer 811 and an acceleration control unit 812. Show.

Here, the operation of the encoder 68 will be described in detail. The encoder 68 includes a light-emitting element such as a light-emitting diode, and a plurality of light-receiving elements such as photodiodes that receive light emitted from the light-emitting element. When the encoder 68 detects the rotation of the code plate 67, the light emitting element continuously emits light, and two pulse signals ENC-A and ENC-B are generated and controlled based on the light receiving states of the plurality of light receiving elements. To the unit 70. ENC-A and ENC-B are signals that are 90 degrees out of phase. Regardless of whether the rotation direction of the paper feed motor 60 is normal or reverse, the period of ENC-A and ENC-B is equal to the time for which the code plate 67 rotates by the interval of the slit.
The pulse signals ENC-A and ENC-B output from the encoder 68 are input to the DC unit 80.

  The rotational position calculation unit 801 included in the DC unit 80 detects the rising edge and the falling edge of each of the output pulses ENC-A and ENC-B of the encoder 68, counts the number of detected edges, and outputs the count value. Based on the above, the rotational position of the paper feed motor 60 is calculated. In this count, when the paper feed motor 60 is rotating forward, the count value is incremented (+1) every time one edge is detected, and when the paper feed motor 60 is rotating backward, Decrement (-1) each time an edge is detected. As described above, the period of each of the pulses ENC-A and ENC-B is equal to the time of the code plate 67 from when one slit passes through the encoder 68 until the next slit passes through the encoder 68, and The pulse ENC-A and the pulse ENC-B are different in phase by 90 degrees. For this reason, the count value “1” by the count corresponds to ¼ of the slit interval of the code plate 67. If the count value is multiplied by ¼ of the slit interval, based on the multiplication value, The rotation amount of the code plate 67 from the rotation position corresponding to the count value “0”, that is, the movement amount of the paper feed motor 60 can be obtained. Therefore, it can be said that the encoder 68 has a resolution corresponding to ¼ of the slit interval of the code plate 67.

The subtractor 802 calculates a rotational position deviation between the target rotational position output from the CPU 71 and the actual rotational position of the paper feed motor 60 obtained by the rotational position calculation unit 801.
A target rotational speed calculation unit 803 calculates the target rotational speed of the paper feed motor 60 based on the rotational position deviation that is the output of the subtractor 802. This calculation is performed by multiplying the rotational position deviation by the gain KP. This gain KP is determined according to the rotational position deviation. Note that the value of the gain KP may be stored in a table (not shown).
The rotation speed calculation unit 804 calculates the rotation speed of the paper feed motor 60 based on the output pulses ENC-A and ENC-B of the encoder 68. In this calculation, first, the rising edge and the falling edge of each of the output pulses ENC-A and ENC-B of the encoder 68 are detected, and the time interval between the edges, that is, the slit interval of the code plate 67 is set to ¼. The corresponding time is counted by the timer counter. Based on the count value, the slit interval of the code plate 67, and the reduction ratios of the pulley 61 and the paper discharge gear 63, the paper discharge gear 63 and the transmission wheel 64, and the transmission wheel 64 and the paper feed roller 65, The rotational speed of the motor 60 is obtained.
A subtractor 805 calculates a deviation between the target rotation speed and the actual rotation speed of the paper feed motor 60 calculated by the rotation speed calculation unit 804.
The proportional element 806 multiplies the deviation by a proportional term constant Gp and outputs the multiplication result. The integration element 807 integrates the deviation multiplied by the integral term constant Gi, and outputs the integration result. The differential element 808 multiplies the difference between the current deviation and the previous deviation by a differential term constant Gd, and outputs the multiplication result. The calculation by the proportional element 806, the integral element 807, and the derivative element 808 is performed for each period of the output pulse ENC-A of the encoder 68, for example, in synchronization with the rising edge of the output pulse ENC-A.

The signal values output from the proportional element 806, the integral element 807, and the differential element 808 are values expressed as duties according to the respective calculation results, and the adder 809 includes the proportional element 806, the integral element 807, and the differential element. Add the outputs of element 808. The addition result is output as a duty signal to the PWM circuit 810, and the PWM circuit 810 generates a command signal corresponding to the addition result. The paper feed motor 60 is driven by the paper feed motor driver 82 based on this command signal.
PID (Proportional, Integral, Differential) control using the proportional element 806, the integral element 807, and the derivative element 808 is used for constant speed control and deceleration control after acceleration control.

Further, the timer 811 generates a timer interrupt signal every predetermined time based on the clock signal output from the CPU 71. The acceleration control unit 812 integrates a predetermined duty DXP every time the timer interrupt signal is received, and the integration result is output to the PWM circuit 810 as a duty signal. As in the case of PID control, the PWM circuit 810 generates a command signal corresponding to the integration result, and the paper feed motor driver 82 drives the paper feed motor 60 based on the generated command signal. The control using the timer 811 and the acceleration control unit 812 is used for acceleration control of the paper feed motor 60.
The paper feed motor driver 82 includes, for example, four transistors, and turns on or off each of the transistors based on the output of the PWM circuit 810, thereby applying a voltage to the paper feed motor 60 and causing the paper feed motor 60 to operate. Make it work.

Next, the outline of the operation of the DC unit 80, that is, the outline of the motor control method will be described with reference to FIG. FIGS. 7A and 7B are charts showing the duty signal value output to the PWM circuit 810 and the motor rotation speed in contrast, where FIG. 7A shows the duty signal value and FIG. 7B shows the paper feed. The rotational speed of the motor 60 is shown.
When a start command signal for starting the paper feed motor 60 is output from the CPU 71 to the DC unit 80 while the paper feed motor 60 is stopped, a start initial duty signal (signal value: DX0) is sent from the CPU 71 to the acceleration control unit. 812 and output from the acceleration control unit 812 to the PWM circuit 810. The starting initial duty signal is converted into a command signal corresponding to the signal value DX0 by the PWM circuit 810 and output to the paper feed motor driver 82, and the paper feed motor driver 82 starts the paper feed motor 60.
After the start command signal is input from the CPU 71, the acceleration control unit 812 sets a predetermined duty to the signal value DX0 of the start initial duty signal in synchronization with the timer interrupt signal input from the timer 811 every predetermined time. A duty signal having the integrated duty as a signal value is output to the PWM circuit 810. The PWM circuit 810 converts the input duty signal into a command signal corresponding to the signal value and outputs the command signal to the paper feed motor driver 82. The paper feed motor driver 82 drives the paper feed motor 60 based on the command signal input from the PWM circuit 810, and the rotational speed of the paper feed motor 60 increases as shown in FIG. 7B. At this time, the value of the duty signal input from the acceleration controller 812 to the PWM circuit 810 is stepped as shown in FIG.

The duty integration process in the acceleration control unit 812 is performed until the integrated duty reaches a constant duty DXS. When the duty integrated at time tl in FIG. 7A reaches a predetermined value DXS, the acceleration control unit 812 stops the integration process, and thereafter, as shown in FIG. A duty signal having a constant duty DXS as a signal value is output.
Then, in order to prevent the rotation speed of the paper feed motor 60 from overshooting, when the rotation speed of the paper feed motor 60 shown in FIG. 7B reaches a predetermined rotation speed V1 (time t2), an acceleration control unit. In step 812, control is performed so as to reduce the voltage applied to the paper feed motor 60. Here, the rotational speed of the paper feed motor 60 further increases, but when the rotational speed of the paper feed motor 60 reaches a predetermined rotational speed Vc (time t3), the PWM circuit 810 is used to control the paper feed motor 60. The duty signal is switched from the output of the acceleration control unit 812 to the output of the adder 809. Thereafter, the drive control of the paper feed motor 60 is executed by PID control using the proportional element 806, the integral element 807, and the differential element 808. Note that the integral value of the integral element 807 is set to an appropriate value at the start of PID control.

When the PID control is started, the target rotational speed is calculated based on the rotational position deviation between the target rotational position and the actual rotational position obtained from the output of the encoder 68. From the target rotational speed and the output of the encoder 68, Based on the rotational speed deviation from the actual rotational speed to be obtained, the proportional element 806, the integral element 807, and the derivative element 808 perform proportional calculation, integral calculation, and differential calculation, and based on the sum of these calculation results. The paper feed motor 60 is controlled. The proportional calculation, integration calculation, and differentiation calculation are performed in synchronization with the rising edge of the output pulse ENC-A of the encoder 68, for example. Thereby, the paper feed motor 60 is controlled so that the rotation speed becomes a desired rotation speed Ve.
When the paper feed motor 60 approaches the target rotation position (time t5 in FIG. 7B), the rotation position deviation decreases, so the target rotation speed also decreases. As a result, the rotational speed deviation, that is, the output of the subtractor 805 becomes negative, so the paper feed motor 60 is decelerated and then stops (time t6).

By the way, as described above, the timing belt 62 that transmits the rotation of the paper feed motor 60 is made of a material containing glass fiber. Due to the characteristics of the glass fiber, the timing belt 62 is operated during the operation of the paper feed motor 60. May shrink. The contraction of the timing belt 62 is a phenomenon that occurs due to the high temperature of the timing belt 62. The reason for the high temperature of the timing belt 62 is that heat is generated in the timing belt 62 itself due to friction between the timing belt 62 and the pulley 61 and the paper discharge gear 63, and the heat of the paper feed motor 60 that generates heat during operation. Is transmitted to the timing belt 62 via the rotary shaft 60 </ b> A and the pulley 61.
When the timing belt 62 contracts, the tension of the timing belt 62 between the paper discharge gear 63 and the pulley 61 increases, and the load applied to the paper feed motor 60 increases. For this reason, since the load that is measured in advance and is the premise for controlling the paper feed motor 60 is different from the load that is actually applied to the paper feed motor 60, the accuracy of the control of the paper feed motor 60, that is, the recording paper 20 There is a concern that the accuracy of the transport operation is lowered.
In addition, even when the timing belt 62 is made of a material that does not contain glass fiber, there is a possibility that the timing belt 62 may be extended due to the high temperature of the timing belt 62. The load that is a precondition for the control of the motor 60 is different from the load that is actually applied to the paper feed motor 60.

Therefore, in the printer 10, the temperature detection unit 69 attached to the paper feed motor 60 detects the temperature of the paper feed motor 60 to cope with a change in the load of the paper feed motor 60 due to a change in the state of the timing belt 62. Control is possible.
The temperature of the timing belt 62 rises according to the operation amount of the timing belt 62, that is, the operation amount of the paper feed motor 60. On the other hand, the temperature of the paper feed motor 60 also rises according to the operation amount. In addition, since the temperature conditions of the environment where the paper feed motor 60 and the timing belt 62 are placed are almost the same, the temperature of the paper feed motor 60 and the temperature of the timing belt 62 have a correlation. Accordingly, the temperature detection unit 69 detects the temperature of the paper feed motor 60, and controls the operation of the paper feed motor 60 based on the temperature of the paper feed motor 60, whereby the timing belt caused by the temperature change of the timing belt 62 is obtained. It is possible to accurately cope with 62 state changes.
Control according to the temperature of the timing belt 62 is realized by changing parameters related to the operations of the proportional element 806, the integral element 807, and the differential element 808 used for PID control.

FIG. 8 is a chart showing the relationship between the temperature of the paper feed motor 60 detected by the temperature detector 69 and the load applied to the paper feed motor 60. In FIG. 8, when the initial load (initial drive load) of the paper feed motor 60 is F1, F2, F3 (where F1 <F2 <F3), the temperature of the paper feed motor 60 and the load applied to the paper feed motor 60 Shows the relationship. In the chart shown in FIG. 8, the temperature of the paper feed motor 60 is divided into temperature regions T1, T2, and T3, and the load applied to the paper feed motor 60 is divided into load regions f1, f2, f3, and f4. The relationship between the load area and each load area is shown for each initial load size.
FIG. 9 is a diagram schematically showing the configuration of the load range table 80A determined based on the relationship between each temperature range and each load range shown in FIG.

  As shown in FIG. 8, when the initial load of the paper feed motor 60 is F1, F2, or F3, the load applied to the paper feed motor 60 increases in proportion to the temperature rise of the paper feed motor 60. That is, in the case of the initial load F1, the load in the temperature range T1 is in the load range f1, the load in the temperature range T2 is in the load range f2, and the load in the temperature range T3 is in the load range f3. In the case of the initial load F2, the load in the temperature range T1 is in the load range f2, and the loads in the temperature ranges T2 and T3 are in the load range f3. In the case of the initial load F3, the load in the temperature ranges T1 and T2 is in the load range f3, and the load in the temperature range T3 is in the load range f4. The load range table 80A shown in FIG. 9 determines the load range for each temperature range for each of the initial loads F1, F2, and F3 based on the relationship shown in FIG. 8 obtained by the evaluation performed in advance. It is done.

Furthermore, the printer 10 prepares a plurality of constants Gp, Gi, and Gd in the proportional element 806, the integral element 807, and the differential element 808 corresponding to the load areas f1 to f4, and according to the load area from the plurality of constants. Use appropriate constants.
FIG. 10 is a diagram schematically showing the configuration of a constant table 80B that defines the correspondence between the load ranges and the constants Gp, Gi, and Gd in the proportional element 806, the integral element 807, and the differential element 808. According to the table shown in FIG. 10, in the load region f1, the value of the proportional term constant Gp is set to p _1, the value of the integral term constant Gi is set to i _1, the value of the differential term constant Gd is d ₁ Set to Further, in the load region f2, the value of the proportional term constant Gp is set to p _2, the value of the integral term constant Gi is set to i _2, the value of the differential term constant Gd is set to d _2. Similarly, in the load region f3, the value of the proportional term constant Gp is set to p _3, the value of the integral term constant Gi is set to i _3, the value of the differential term constant Gd is set to d _3, load zone in f4, the value of the proportional term constant Gp is set to p _4, the value of the integral term constant Gi is set to i _4, the value of the differential term constant Gd is set to d _4.

  Both the load area table 80A shown in FIG. 9 and the constant table 80B shown in FIG. 10 are stored in the EEPROM 78 as storage means included in the control unit 70 and read by the CPU 71 in a recording process (FIG. 11) described later. The CPU 71 determines the temperature of the paper feed motor 60 based on the resistance value of the thermistor in the temperature detection unit 69 connected to the DC unit 80, the temperature range including this temperature, and the initial load in the current paper feed motor 60. And the load range set in the load range table 80A is acquired. Subsequently, the CPU 71 acquires a constant corresponding to the acquired load range from the constant table 80B, outputs the constant to the DC unit 80, and sets it as constants of the proportional element 806, the integral element 807, and the differential element 808. With this operation, the DC unit 80 can execute the PID control using a constant suitable for the load applied to the current paper feed motor 60.

FIG. 11 is a flowchart showing a recording process executed by the CPU 71. In the recording process shown in FIG. 11, the CPU 71 functions as the control means of the present invention.
The recording process shown in FIG. 11 is started when the printer 10 is turned on (step S1). First, the CPU 71 detects the initial load of the paper feed motor 60 (step S2). Here, the detection of the initial load is performed by, for example, a method in which the paper feed motor 60 is energized on a trial basis by the DC unit 80 and current is measured.
Subsequently, the CPU 71 determines the presence / absence of recording data for recording an image on the recording paper 20, and if there is no recording data, the CPU 71 waits until the recording data is input via the IF unit 74 and becomes recordable. (Step S3).
If there is recording data to be recorded on the recording paper 20 (step S3; Yes), the CPU 71 drives the paper feed motor 60 to take in the recording paper 20 from the paper feed tray 13 (step S4).

After taking in the recording paper 20, the CPU 71 detects the temperature of the paper feed motor 60 using the temperature detector 69 (step S5). Then, the CPU 71 refers to the load area table 80A and the constant table 80B based on the temperature of the paper feed motor 60 detected using the temperature detection unit 69 and the initial load detected in step S2, and the proportional element 806, Constants Gp, Gi, Gd used in the integration element 807 and the differentiation element 808 are set (step S6).
Thereafter, the CPU 71 ejects ink from the recording head 32 and records an image on the recording paper 20 (step S7). Here, while recording an image on the recording paper 20, the CPU 71 detects the presence or absence of a page break (step S8). When recording of the currently recorded page is completed (step S8; Yes), the CPU 71 operates the paper feed motor 60 to discharge the currently recorded sheet from the paper discharge port 14 (step S9). Then, it is determined whether or not recording for the next page is executed (step S10). Here, when recording the next page (step S10; No), the process returns to step S4, and the recording paper 20 of the next page is taken from the paper feed tray 13. If all pages have been recorded (step S10; Yes), this process ends.

As described above, according to the printer 10 according to the embodiment of the present invention, an image is recorded on the recording paper 20 in the printer 10 having a configuration in which the power of the paper feed motor 60 is transmitted to the transport mechanism unit 30B by the timing belt 62. PID control proportional term constant Gp, integral term constant Gi, based on the temperature of the paper feed motor 60 detected by the temperature detector 69 and the initial load of the paper feed motor 60 when executing the recording process to be performed. Since the differential term constant Gd is set, the timing belt 62 expands or contracts when the temperature of the timing belt 62 becomes extremely high, for example, when images are continuously recorded on a large amount of recording paper 20. However, the paper feed motor 60 can be accurately controlled by setting an optimal constant that takes into account the state change of the timing belt 62. It can, it is possible to operate with high accuracy. Each constant set during the recording operation is stored in the EEPROM 78 in association with the initial load of the paper feed motor 60 and the temperature range of the paper feed motor 60, and the CPU 71 corresponds to the stored constant. What is necessary is just to read and set things. For this reason, the process of setting the constant in the recording process can be completed in a very short time, and the throughput is not reduced. Further, the configuration for detecting the temperature of the paper feed motor 60 by the temperature detector 69 is very simple and can be easily realized.
Further, since the CPU 71 sets a constant based on the temperature detected by the temperature detection unit 69 and the initial load of the paper feed motor 60 every time a page break operation is performed in the recording process, the CPU 71 records one page. Has the advantage that the constants are not changed and the recording quality within the page is kept uniform. Furthermore, since the frequency of setting the constant is moderately low, there is an advantage that the throughput is not lowered while the state change of the timing belt 62 is accommodated.

The embodiment described above shows one embodiment of the present invention, and it is needless to say that the embodiment can be arbitrarily modified and applied within the scope of the present invention. For example, in the above-described embodiment, the configuration in which the temperature detection unit 69 includes the thermistor has been exemplified. However, the configuration may include a temperature detection unit using a thermocouple, as long as the temperature of the paper feed motor 60 can be detected. The present invention can be applied. In the above-described embodiment, the temperature detection unit 69 detects the temperature of the paper feed motor 60 instead of directly detecting the temperature of the timing belt 62. However, the temperature of the timing belt 62 is directly detected. It is good also as a structure to detect. Furthermore, in the above-described embodiment, the load of the paper feed motor 60 is associated with the initial load and the temperature range of the paper feed motor 60 in the load area table 80A, and the load of the paper feed motor 60 and each load in the constant table 80B. Although the constants are associated with each other, for example, the load area table 80A and the constant table 80B are combined into one table, and a table for associating the initial load of the paper feed motor 60, the temperature area, and each constant is provided. It may be used.
In this embodiment, in the recording process, the temperature of the paper feed motor 60 is detected every time page recording is started, and constants Gp, Gi, and Gd used in the proportional element 806, the integral element 807, and the differential element 808 are set. However, the present invention is not limited to this. For example, the constants Gp, Gi, and Gd may be set by detecting the temperature of the paper feed motor 60 each time a line feed is made. Hereinafter, this example will be described as a first modification.

[Modification 1]
FIG. 12 is a flowchart showing recording processing in a modification of the present embodiment. In the first modification, the configuration of the printer 10 is the same as that in the above embodiment.
When the recording process is started by turning on the printer 10 (step S11), the CPU 71 detects the initial load of the paper feed motor 60 (step S12). Subsequently, the CPU 71 determines the presence / absence of recording data for recording an image on the recording paper 20, and if there is no recording data, the CPU 71 waits until the recording data is input via the IF unit 74 and becomes recordable. (Step S13). If recording data exists (step S13; Yes), the CPU 71 drives the paper feed motor 60 to take in the recording paper 20 from the paper feed tray 13 (step S14).

After taking in the recording paper 20, the CPU 71 detects the temperature of the paper feed motor 60 using the temperature detector 69 (step S15). Then, the CPU 71 refers to the load area table 80A and the constant table 80B based on the temperature of the paper feed motor 60 detected using the temperature detection unit 69 and the initial load detected in step S2, and the proportional element 806, Constants Gp, Gi, Gd used in the integration element 807 and the differentiation element 808 are set (step S16).
Thereafter, the CPU 71 records an image on the recording paper 20 by ejecting ink from the recording head 32 (step S17). Here, while recording an image on the recording paper 20, the CPU 71 detects the presence or absence of a line feed (step S18). When the recording of the currently recorded line ends (step S18; Yes), the CPU 71 determines whether or not to perform a page break operation (step S19). That is, after the recording of a certain line is completed, it is determined whether recording is performed on the next line in the currently recorded page, or whether recording of the currently recorded page is terminated. When recording is performed on the next line in the page (step S19; No), the CPU 71 returns to step S15 and performs an operation of detecting the temperature of the paper feed motor 60 by the temperature detection unit 69. When recording of the currently recorded page is to be ended (step S19; Yes), the CPU 71 operates the paper feed motor 60 to discharge the currently recorded sheet from the paper discharge port 14 (step S20). It is determined whether or not recording is to be performed on the current page (step S21). Here, when recording the next page (step S21; No), the process returns to step S14, and the next recording sheet 20 is taken in from the paper feed tray 13. If all pages have been recorded (step S21; Yes), this process ends.

  As described above, when the temperature of the paper feed motor 60 is detected every time a line feed is performed and the constants Gp, Gi, and Gd corresponding to the temperatures are set, the temperature detected by the temperature detection unit 69 and the paper feed motor 60 are set. By setting the constant based on the initial load at a high frequency, there is an advantage that a change in the state of the timing belt 62 can be quickly dealt with.

  In the above-described embodiment and Modification 1, the temperature detection unit 69 is disposed on the side surface of the paper feed motor 60. However, the present invention is not limited to this, and for example, the temperature detection unit 69 is provided. It is good also as a structure incorporated in the paper feed motor 60. FIG. Hereinafter, this example will be described as a second modification.

[Modification 2]
FIG. 13 is a perspective view showing the configuration of the paper feed motor 60 in Modification 2 of the present embodiment. As shown in FIG. 13, the paper feed motor 60 according to the second modification includes a temperature detection unit 69A therein. The temperature detection unit 69 </ b> A includes a substrate formed in a disk shape in accordance with the cross-sectional shape of the paper feed motor 60, a thermistor and an output terminal mounted on the substrate, and wiring from the output terminal to the outside of the paper feed motor 60. Is pulled out and connected to the control unit 70. The temperature detector 69 </ b> A is disposed inside the surface of the paper feed motor 60 on which the rotating shaft 60 </ b> A protrudes. A hole having a diameter larger than that of the rotation shaft 60A of the paper feed motor 60 is formed at the center of the substrate of the temperature detection unit 69A, and the rotation shaft 60A passes through the hole.
In the paper feed motor 60 configured as shown in FIG. 13, the temperature in the vicinity of the rotation shaft 60A is detected by the temperature detection unit 69A. As described above, the timing belt 62 (FIGS. 3 and 4), in addition to the heat generated in the timing belt 62 itself due to friction between the pulley 61 and the paper discharge gear 63, is fed from the paper feed motor 60 via the rotary shaft 60A. In response to the heat transferred, the temperature rises. Therefore, if the temperature in the vicinity of the rotating shaft 60A is detected by the temperature detection unit 69A, a temperature closer to the temperature of the timing belt 62 can be detected, and the change in the state of the timing belt 62 can be dealt with more accurately. .

1 is an external perspective view illustrating a configuration of a printer according to an embodiment of the present invention. FIG. 3 is a perspective view illustrating a configuration of a recording mechanism unit included in the printer. FIG. 4 is a perspective view illustrating a configuration of a transport mechanism unit included in the printer. It is a principal part enlarged view of FIG. FIG. 3 is a block diagram illustrating a functional configuration of a printer control unit. It is a block diagram which shows the structure of DC unit with which a control part is provided in detail. It is a graph which shows the duty signal value and motor rotational speed which are output to a PWM circuit. It is a graph which shows the relationship between the temperature of a paper feed motor, and load. It is a figure which shows the structure of a load area table typically. It is a figure which shows the structure of a constant table typically. It is a flowchart which shows the recording process performed by CPU. 10 is a flowchart showing a recording process in Modification 1. FIG. 10 is a perspective view showing a configuration of a paper feed motor in Modification 2.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Printer (recording apparatus), 20 ... Recording paper, 30A ... Recording mechanism part, 30B ... Conveyance mechanism part (driven system), 51 ... Paper feed roller, 52 ... Paper feed roller shaft, 53 ... Paper feed roller, 54 ... driven roller, 56 ... paper discharge roller, 57 ... paper discharge roller shaft, 58 ... jagged roller, 60 ... paper feed motor (motor), 60A ... rotating shaft, 61 ... pulley, 62 ... timing belt, 63 ... paper discharge gear, 64 ... transmission wheel, 65 ... large gear, 66 ... paper feed gear, 67 ... sign plate, 68 ... encoder, 69 ... temperature detector (temperature detector), 70 ... controller, 71 ... CPU (controller), 78 ... EEPROM (storage means), 80 ... DC unit, 82 ... paper feed motor driver, 806 ... proportional element, 807 ... integral element, 808 ... differential element, 810 ... PWM circuit.

Claims (7)

A recording operation for recording an image on a recording medium includes a motor, a timing belt that transmits the power of the motor to a driven system, and a control unit that performs arithmetic processing using parameters to control the operation of the motor. In the recording device to perform
A temperature detecting means for detecting the temperature of the timing belt or a temperature correlated with the temperature of the timing belt;
The control means sets the parameter based on the temperature detected by the temperature detection means and the initial driving load of the motor when the recording operation is executed.
A recording apparatus. The control means controls the operation of the motor by a method including PID control,
The parameters include a proportional term constant, an integral term constant, and a derivative term constant in the PID control.
The recording apparatus according to claim 1. The control means includes
A storage means for storing the parameter in association with the temperature range of the timing belt and the initial driving load,
When performing the recording operation, reading and setting the parameter stored in the storage unit based on the temperature range corresponding to the temperature detected by the temperature detection unit and the initial driving load;
The recording apparatus according to claim 1 or 2. The control means sets the parameter based on the temperature detected by the temperature detection means and the initial driving load every time a page break operation is performed during execution of the recording operation.
The recording apparatus according to claim 1, wherein the recording apparatus is a recording apparatus. The control means sets the parameter based on the temperature detected by the temperature detection means and the initial driving load every time a line feed operation is performed during execution of the recording operation.
The recording apparatus according to claim 1, wherein: The temperature detecting means detects the temperature of the motor as a temperature having a correlation with the temperature of the timing belt;
The recording apparatus according to claim 1, wherein: In a recording apparatus comprising a motor and a timing belt that transmits the power of the motor to a driven system, a motor control method for controlling the operation of the motor by performing arithmetic processing using parameters,
When executing the recording operation, the temperature of the timing belt or a temperature correlated with the temperature of the timing belt is detected, and the parameter is set based on the detected temperature and the initial driving load of the motor. Setting,
A motor control method in a recording apparatus.

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