JP2006056194A - Transfer controller and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transfer controller capable of highly accurately stopping a transfer belt by detecting a moving distance of the transfer belt without directly detecting the rotation of a transfer motor by a rotary encoder. <P>SOLUTION: A linear scale 41 and an encoder sensor 7, which is capable of reading the amount of movement of the transfer belt 4, are mounted to the back of the transfer belt 4. An output signal from the encoder sensor 7 is transmitted to an LD current deciding part 61 of a control part 6. The number of pulses measured with the LD current deciding part 61 is analyzed. A current value (the magnitude of an input current) supplied to an LD is decided. By this, the analysis result can be fed back to an output signal of a drive motor by the LD, which can output an output signal corresponding to an ultra-minute moving distance of the transfer belt 4, and a PD capable of accurately receiving the output signal from the LD. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transport control device for transporting an object to be transported such as paper and PCB parts with high accuracy, and an image forming apparatus equipped with the transport control device.

As this type of technology, for example, the invention disclosed in Patent Document 1 is known. In the present invention, the slits provided at equal intervals in the code generation unit of the scale unit provided along the edge of the conveyance belt for conveying the recording paper to the printing unit are detected by the encoder sensor and output in the sub-scanning direction. The printing start position is designated, the printing position in the sub-scanning direction is prevented from being shifted, and an image having no color shift is formed.
JP 2004-17505 A

  As described above, current image processing apparatuses use a rotary encoder that rotates in conjunction with a motor as means for measuring the paper feed amount. However, it is difficult to install the shaft for rotating the rotary encoder in the middle without any deviation, and it is difficult to ensure the stop position accuracy. In order to avoid this problem, accurately measure the paper conveyance distance, and ensure the stop position accuracy, it is desirable to directly measure the movement distance of the paper conveyance belt.

  The present invention has been made in view of such a background, and an object of the present invention is to detect the moving distance of the conveying belt without directly detecting the rotation of the conveying motor by the rotary encoder and to stop the conveying belt with high accuracy. It is to be able to let you.

  In order to achieve the object, the transport control device according to the first means includes means for outputting the travel distance of the transport belt from sensors linked to the travel distance of the transport belt, and output output from the output means. It is characterized by comprising means for reading a signal in precise units, and means for feeding back the output signal read by the reading means to a motor for driving the conveyor belt.

  The second means stops when the signal obtained by the means for reading the output signal in a precise unit reaches a preset value when the means for feeding back to the motor for driving the conveyor belt in the first means. When the signal is sent to the motor and the motor does not stop at the intended position, the output operation from the means for outputting the moving distance of the conveyor belt and the output signal output from the output means in precise units. A reading operation of the reading unit and an operation of feeding back the read output signal to a motor that drives the conveyance belt are repeated, and the conveyance belt can be stopped at a target position.

  The third means is that in the first or second means, the means for outputting the moving distance of the conveyor belt outputs an output signal from a sensor for reading the number of striped patterns finely drawn on the conveyor belt at equal intervals. It is analyzed and linked to the magnitude of the input current of the laser diode.

  According to a fourth means, in the first or second means, the means for outputting the movement distance of the conveyor belt receives and analyzes the input signal to the motor in parallel, and detects the movement distance. It is linked to the magnitude of the input current of the diode.

  According to a fifth means, in the first or second means, the means for outputting the moving distance of the conveyor belt is linked with the gear of the motor, and the magnitude of the input current of the laser diode for detecting the moving distance. It is characterized by being linked to the height.

  A sixth means is the first or second means, wherein the means for outputting the moving distance of the conveyor belt outputs an output signal from a sensor that reads the number of striped patterns drawn on the conveyor belt finely at equal intervals. It is characterized by being linked to the magnitude of the voltage applied to the piezo actuator mounted on the diffraction grating on which the output light of the laser diode for analyzing and detecting the moving distance is projected.

  The seventh means is a laser diode in the first or second means, wherein the means for outputting the moving distance of the conveyor belt receives and analyzes the input signal to the motor in parallel and detects the moving distance. The output light is linked to the magnitude of the voltage applied to the piezoelectric actuator attached to the diffraction grating on which the output light is projected.

  According to an eighth means, in the first or second means, the means for outputting the moving distance of the conveyor belt projects the output light of the laser diode for detecting the moving distance in conjunction with the gear of the motor. It is characterized by being interlocked with the magnitude of the voltage applied to the piezoelectric actuator attached to the diffraction grating.

  According to a ninth means, in the first or second means, the means for reading the output signal in a precise unit detects the change in the value of the photodiode inside the laser diode for detecting the moving distance, and the conveyor belt. It is characterized by reading the movement distance of

  According to a tenth means, in the first or second means, the means for reading the output signal in a precise unit is a laser diode output light, a transmitted light from a diffraction grating onto which the laser diode output light is projected, and Receiving at least one of the reflected light from the diffraction grating onto which the output light of the laser diode is projected, and measuring the frequency of the light directly by homodyne to replace the moving distance of the conveyor belt with the frequency of the light. It is characterized by.

  According to an eleventh means, in the first or second means, the means for reading the output signal in precise units is an output light of a laser diode for detecting the moving distance, and a laser for detecting the moving distance. Receiving at least one of the transmitted light from the diffraction grating onto which the output light of the diode is projected and the reflected light from the diffraction grating onto which the output light of the laser diode for detecting the moving distance is projected; It is characterized in that the distance of movement of the conveyor belt is replaced with the frequency of light by measuring the frequency of light directly with a heterodyne.

  A twelfth means is characterized in that, in the eleventh means, the reference light includes an optical frequency comb.

  The thirteenth means further comprises means for linking the movement position of the carriage holding the print head with the magnitude of the input current of the second laser diode for detecting the movement distance in the eleventh means, A paper conveying belt by measuring a carriage moving distance by a second laser diode for detecting the moving distance in a frequency band different from that of the first laser diode for detecting a moving distance used for measuring the belt moving distance. The simultaneous measurement of the moving distance and the carriage moving distance is performed by one heterodyne frequency measuring device.

  In a fourteenth aspect, in any one of the third to fifth means, when the characteristics of the laser diode change or when the characteristics of the laser diode vary, the set temperature of the laser diode is set. It is characterized by changing.

  The fifteenth means is characterized in that the image forming apparatus includes a conveyance control device according to any one of the first to fourteenth means.

  In the following embodiments, the sensors output the moving distance of the conveyor belt to the encoder sensor 7, LD 11 or PZT 14, and the means for reading in precise units to the PD 11 a, the homodyne frequency measuring unit 15 or the heterodyne frequency measuring unit 16. The means, the means for feeding back to the motor, and the means for interlocking with the magnitude of the input current of the laser diode correspond to the control unit 6, and the means for changing the set temperature of the temperature of the laser diode correspond to the LD temperature setting unit 70, respectively.

  According to the present invention, the travel distance of the transport belt can be detected without directly detecting the rotation of the transport motor by the rotary encoder, and the transport belt can be stopped with high accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of an ink jet recording apparatus according to an embodiment of the present invention. The ink jet recording apparatus 1 includes an ink jet head 2, a paper feed unit 3 having two paper feed stages, a paper transport unit 4, and a paper discharge unit 5. The ink jet head 2 moves in the main scanning direction. The paper fed from the paper feed unit 3 is transported in the sub-scanning direction by the paper transport unit 4 and printing is performed on the paper. In this embodiment, the sheet conveying unit 4 is composed of an electrostatic adsorption type conveying belt, and conveys the sheet while adsorbing the sheet.

  FIG. 2 is a block diagram showing a control configuration of the ink jet recording apparatus of FIG. The ink jet recording apparatus 1 includes a control unit 6, an encoder sensor 7 connected to the control unit 6, a drive motor 9 connected via a driver 8, and an ink jet head 2 connected via a head control unit 10. Basically configured, for example, a personal computer PC is externally connected to the control unit 6 as an external device. In accordance with a program stored in a ROM (not shown), the control unit 6 executes the program while using a RAM (not shown) as a work area, and performs predetermined control. The controller 6 is connected to an LD (laser diode) 11 and / or a PZT (piezo actuator) 14 for detecting the speed of the conveyor belt, and a PD (photodiode) for detecting light emission of the LD 11. 11a is also connected.

  FIG. 3 is a flowchart showing a processing procedure of the control unit 6. In this process, since the input current and applied voltage to the electrical components (LD11, PZT14) change in conjunction with the moving distance of the conveyor belt 4 (steps S101 and S102), the output signals from the electrical components are received and analyzed. (The PD output of the LD 11 and the measurement result from the frequency measuring device are analyzed by the conveyor belt control unit) (step S103), and the output signal to the drive motor 9 is fed back (step S104), thereby super-precision control of the paper conveyance. Is realized.

  FIG. 4 is a diagram showing a configuration for the control. Here, in order to output the moving distance of the conveying belt 4 from the sensors linked with the moving distance of the conveying belt 4, the output from the encoder sensor 7 that reads the number of striped patterns finely drawn on the conveying belt 4 at equal intervals. The signal (number of pulses) is analyzed and linked to the magnitude of the input current of the LD 11. Therefore, in the present embodiment, a linear scale 41 is attached to the back of the conveyor belt (indicated as a paper conveyor belt in the figure) 4 and an encoder sensor that can read how much the conveyor belt 4 has moved (in the figure, simply an encoder). And display) 7 is also attached. An output signal from the encoder sensor 7 is sent to the LD current determination unit 61 of the control unit 6, analyzes the number of pulses measured by the LD current determination unit 61, and supplies a current value (input current of the input current) to the LD (laser diode) 11. Size).

  If comprised in this way, the electrical equipment (LD11) which can output the output signal corresponding to the very minute movement distance of the conveyance belt 4, and the electrical equipment which can receive correctly the output signal from the electrical equipment (LD11) The analysis result can be fed back to the output signal of the drive motor 9 depending on the product (PD11a). Thereby, color misregistration can be prevented by ultra-precise control of the paper transport belt 4.

  FIG. 5 is a diagram showing a configuration for determining the amount of current to be supplied to the LD 11 from a control signal sent to a drive motor (shown as a conveyance motor in the figure). When outputting the travel distance of the transport belt 4 from the sensors linked to the travel distance of the transport belt 4, the input signal to the drive motor 9 for rotating the transport belt 4 is received and analyzed in parallel, and the magnitude of the input current of the LD 11 is analyzed. It is linked to the size. In this configuration, the control signal 9a sent to the drive motor 9 is pulled in parallel to the LD current determination unit 61, and the moving distance of the transport belt 4 is analyzed from the control signal 9a. Then, the amount of current supplied to the LD 11a that changes according to the moving distance of the conveyor belt 4 is determined.

  If comprised in this way, the movement distance of the conveyance belt 4 will be recognized from the pulse number which the linear scale 41 attached to the back of the paper conveyance belt 4 was counted by the encoder sensor 7, and the input electric current amount to LD11 will be changed. Therefore, it is possible to output the change of the PD output power (PD11a output) and the oscillation frequency of the LD 11 up to the minute movement amount of the conveyor belt 4.

  FIG. 6 is a diagram showing a configuration for determining the amount of current supplied to the LD 11 by measuring the rotational speed of the drive motor 9. When outputting the movement distance of the conveyance belt 4 from the sensors linked to the movement distance of the conveyance belt 4, the rotation speed of the gear of the motor that rotates the conveyance belt 4 is linked to the magnitude of the input current of the LD 11. In this configuration, the rotational speed of the drive motor 9 is directly measured, and the amount of current supplied to the LD 11 is determined by the LD current determination unit 61 of the control unit 6.

  With this configuration, the movement distance of the conveyor belt 4 is analyzed from the output signal to the motor 9 that drives the conveyor belt 4, and the amount of input current to the LD 11 is changed. Until then, it can be output as a change in the PD output power (PD11a output) and oscillation frequency of the LD11.

  FIG. 7 is a diagram showing a configuration for determining a voltage applied to a PZT (piezo actuator) 14 from an encoder output. An output signal from a sensor (encoder sensor 7) that reads the number of striped patterns drawn on the conveyor belt 4 at equal intervals when outputting the distance of the conveyor belt 4 from sensors linked to the distance of movement of the conveyor belt 4 (Pulse number) is analyzed and linked to the magnitude of the voltage applied to the PZT (piezo actuator) 14 attached to the diffraction grating 13 to which the output light of the LD 11 hits. In this configuration, a linear scale 41 is attached to the back of the conveyor belt 4, and an encoder sensor 7 that can read how much the conveyor belt 4 has moved is also attached. The output signal from the encoder sensor 7 is sent to the PZT application voltage determination unit 62 of the control unit 6, and the voltage value applied to the PZT 14 is determined from the number of pulses detected by the encoder sensor 7.

    If comprised in this way, if the linear scale 41 attached to the back of the paper conveyance belt 4 is converted into the number of pulses counted by the encoder sensor 7 and the applied voltage of the PZT 14 is changed, the conveyance belt 4 is moved. This is equivalent to directly outputting the moving distance of 4, and the moving amount of the minute conveying belt 14 can be controlled at low cost without using a large-scale mechanical structure.

  FIG. 8 is a diagram showing a configuration for determining a voltage to be applied to the PZT 14 from a control signal sent to the drive motor 9. The moving distance of the conveyor belt 4 is determined by the input signal of the drive motor 9. Therefore, in this configuration, the control signal 9a sent to the drive motor 9 is drawn in parallel to the PZT applied voltage determination unit 62 of the control unit 6, and the moving distance of the conveyor belt 4 is analyzed from the control signal 9a. Then, the voltage value applied to the PZT 14 that changes according to the moving distance of the conveyor belt 4 is determined.

  With this configuration, the movement distance of the conveyor belt 4 is recognized according to the input signal to the motor 9 that drives the conveyor belt 4, and the applied voltage of the PZT 14 is changed. Until control, it can be output as a change in the frequency of the reflected or transmitted light of the diffraction grating.

  FIG. 9 is a diagram showing a configuration for determining the voltage to be applied to the PZT 14 by measuring the rotational speed of the drive motor 9. When outputting the moving distance of the conveying belt 4 from the sensors linked to the moving distance of the conveying belt 4, the PZT 14 is attached to a diffraction grating that is linked with the gear of the drive motor 9 that rotates the conveying belt 4 and that the output light of the LD 11 strikes. It is linked to the magnitude of the voltage applied to the. In this configuration, the rotational speed of the drive motor 9 is directly measured, and the applied voltage value to the PZT 14 is determined by the PZT applied voltage determining unit 62 of the control unit 6.

  With this configuration, the movement distance of the conveyance belt 4 is analyzed from the output signal to the motor 9 that drives the conveyance belt 4 and the applied voltage to the PZT 14 is changed. , And output as a change in the frequency of the reflected light or transmitted light of the diffraction grating.

  FIG. 10 is a diagram illustrating a configuration in which IV conversion is performed based on an output signal of a PD (photodiode) 11a when the current value to the LD 11 is changed. In this configuration, when the current value to the LD 11 is changed according to the moving distance of the conveying belt 4, the PD output corresponds to the conveying belt moving distance of 1: 1. Therefore, in order to feedback control the measurement result, IV conversion is performed by the conversion unit 12.

  With this configuration, the optical power is measured by the PD 11a inside the LD 11, so that no mechanical configuration is required, and a small amount of movement of the conveyor belt 4 can be output at low cost.

  In FIG. 11, the output light 11b of the LD 11 or the reflected light 11c or the transmitted light 11d from the diffraction grating of the LD 11 is received, and the moving distance of the conveyor belt 4 is replaced with the light frequency by directly measuring the frequency of the light with homodyne. It is a figure which shows the structure to measure. In this configuration, the output light 11b of the LD 11 is directly input to the homodyne frequency measurement unit 15, or the reflected light 11c reflected by the diffraction grating 13 or the transmitted light 11d transmitted through the diffraction grating 13 is input to the homodyne frequency measurement unit 15. The frequency of the light input by the measuring unit 15 is measured. That is, the inclination of the diffraction grating 13 varies depending on the supply current of the LD 11 and the applied voltage of the PZT 14 attached to the diffraction grating 13 according to the moving distance of the conveyor belt 4. As a result, the frequencies of the output light 11b of the LD 11, the reflected light 11c of the diffraction grating 13, and the transmitted light 11d change. Therefore, by measuring the frequency, the moving distance of the conveyor belt 4 can be measured to a very precise unit. The frequency can be measured by homodyne measurement by the homodyne frequency measurement unit 15.

  With this configuration, the movement distance of the conveyance motor 9 is recognized as a change in the frequency of the received light, and the movement distance of the conveyance belt 4 is changed as the oscillation frequency of the output light 11b of the LD 11 or the reflected light 11c or transmitted light of the diffraction grating 13. Since the frequency change of 11d is measured by the homodyne frequency measurement method, the frequency measurement, that is, the movement distance measurement of the conveyor belt 4 can be performed without reference light.

  FIG. 12 shows the output light 11b of the LD 11 or the reflected light 11c or transmitted light 11d from the diffraction grating 13 of the LD 11 and receives the reference light including the optical frequency comb etc. to measure the frequency of the light directly by heterodyne. It is a figure which shows the structure which replaces the moving distance of the belt 4 with the frequency of light, and measures it. In this configuration, the output light 11 b of the LD 11 is directly input to the heterodyne frequency measurement unit 16, or the reflected light 11 c reflected by the diffraction grating 13 or the transmitted light 11 d transmitted through the diffraction grating 13 is input to the heterodyne frequency measurement unit 15. Measure the frequency of the input light. That is, the inclination of the diffraction grating 13 varies depending on the supply current of the LD 11 and the applied voltage of the PZT 14 attached to the diffraction grating 13 according to the moving distance of the conveyor belt 4. As a result, the frequencies of the output light 11b of the LD 11, the reflected light 11c of the diffraction grating 13, and the transmitted light 11d change. By measuring the frequency, the moving distance of the conveyor belt 4 can be measured to a very precise unit. For example, the frequency is measured by heterodyne measurement by the heterodyne frequency measurement unit 16. In the heterodyne measurement, reference light is required, but in this embodiment, an optical frequency comb generator 17 is installed in the heterodyne frequency measurement unit 16 in order to measure an arbitrary frequency. As a result, it is possible to perform ultraprecise frequency measurement, that is, measurement of the amount of movement of the conveyor belt 4.

  With this configuration, the moving distance of the conveyor belt 4 is set to change the oscillation frequency of the direct light 11b of the LD 11 or the frequency change of the reflected light 11d or transmitted light 11c of the diffraction grating 13 using the reference light such as the optical frequency comb. Since the measurement is performed by the measurement method, it is possible to perform a more precise frequency measurement than the homodyne frequency measurement method, that is, the movement distance measurement of the conveyor belt 4. At this time, the control unit 6 that feeds back the analysis result of the conveyance belt movement distance to the conveyance belt drive motor 9 and finely adjusts the conveyance belt movement distance is equivalent to directly measuring the movement distance of the conveyance belt 4. The movement distance error of the conveyor belt 4 caused by variations in the characteristics and performance of the motor 9 can be complemented.

  As described above, the PZT applied voltage that changes the input current of the LD 11 and the tilt of the diffraction grating 13 changes in conjunction with the moving distance of the conveyor belt 4. Then, the moving distance of the conveyor belt 4 is measured by measuring the power or frequency of the LD 11. The forward / backward fine adjustment movement of the conveyor belt 4 is repeated until the movement distance set before the conveyor belt movement is met. Since there is a hysteresis characteristic in the change in the length of the PZT 14 due to the output of the PD 11a due to the input current of the LD 11, the frequency, and the applied voltage of the PZT 14, the control unit 6 performs control in consideration of this.

FIG. 13 is a flowchart showing a control procedure for performing feedback control using the PD11a output of the LD11.
In this control procedure, first, the travel distance of the transport belt 4 is set in the transport belt control section (same as the control section 6) (step S201), and the transport belt travel distance signal is fed back to the input current of the LD 11 (step S202). The output of the PD 11a is measured (step S203). Then, IV conversion is performed by the IV conversion unit 12 (step S204), and the current transport belt moving distance is measured by the transport belt control unit 6 (step S205). Next, it is checked whether or not the movement distance of the conveyor belt 4 measured after the stop is equal to the initial movement distance (step S207). If not, the process returns to step S203, and if equal, the printing for one scan is terminated. (Step S208), this is repeated until the last scan, and this processing is finished when all the printing is completed (Step S209).

FIG. 14 is a flowchart showing a control procedure for performing feedback control using the frequency of the LD output light.
In this control procedure, first, the travel distance of the transport belt 4 is set in the transport belt controller 6 (step S301), the transport belt travel distance signal is fed back to the input current of the LD 11 (step S302), and homodyne or heterodyne frequency measurement is performed. The units 15 and 16 measure the frequency of the LD output light (step S303). And after measuring the present conveyance belt movement distance in the conveyance belt control part 6 (step S304), a belt stop process is started (step S305). Next, it is checked whether or not the movement distance of the conveyor belt measured after the stop is equal to the initial movement distance (step S306). If it is not equal, the process returns to step S303. In step S307, this process is repeated until the final scan, and the process ends when all printing is completed (step S308).

FIG. 15 is a flowchart showing a control procedure for performing feedback control using the frequency of diffraction grating reflected light or diffraction grating transmitted light.
In this control procedure, first, the travel distance of the transport belt 4 is set in the transport belt controller 6 (step S401), and the transport belt travel distance signal is fed back to the applied voltage of the PZT 14 that changes the tilt of the diffraction grating 13 (step S402). ) The frequency of the LD11 output light is measured by the homodyne or heterodyne frequency measuring units 15 and 16 (step S403). And after measuring the present conveyance belt movement distance in the conveyance belt control part 6 (step S404), a belt stop process is started (step S405). Next, it is checked whether or not the movement distance of the conveyor belt 4 measured after the stop is equal to the initial movement distance (step S406). If not, the process returns to step S403. In step S407), this process is repeated until the last scan, and this processing is completed when all the printing is completed (step S408).

  When the characteristics of the LD 11 change, or when the characteristics of the LD 11 vary, changing the set temperature of the temperature of the LD 11 (maintained at a constant temperature during startup) changes the characteristics due to long-term use. Variations in characteristics can be corrected. A configuration for this purpose is shown in FIG.

  In FIG. 16, the correction circuit that corrects the variation in LD characteristics includes an LD temperature setting unit 70, a thermistor 71 attached to the LD 11, and a Peltier element 72. When the image processing apparatus is activated, the temperature of the LD 11 must always be kept at the set temperature. For this purpose, the signal from the thermistor 71 attached to the LD 11 is confirmed by the LD temperature setting unit 70, the Peltier element 72 is also attached to the high thermal conductivity material attached in contact with the LD 11, and heat is always put in and out. Keep at temperature. When the characteristics of the LD 11 change, the LD temperature setting unit 70 changes the set temperature to correct the characteristics change of the LD 11 and variations in individual LD characteristics.

  Further, when using the input current of the LD 11 whose frequency fluctuates in conjunction with the moving distance of the transport belt 4 and the applied voltage of the PZT 14 and the input current of the LD 11 that changes in conjunction with the carriage moving distance and the applied voltage of the PZT 14, the paper is transported. By using an LD having a frequency band different from that of the LD 11 used for the belt moving distance measurement for the carriage moving distance measurement, the frequency of the paper conveying belt moving distance and the carriage moving distance can be simultaneously measured by one heterodyne frequency measuring device 16. Measurements can be made. This configuration is shown in FIG.

  In FIG. 17, an optical frequency comb is generated at a frequency interval of fGHz, and the frequency band of the LD 11 is determined in advance so that the transport belt 4 moves within the A band and the carriage moves within the B band. By setting in this way, two measurement results are prevented from entering the same band, and simultaneous measurement can be performed with one heterodyne frequency measuring device 17.

  In this embodiment, the sheet conveyance of the image forming apparatus is described as an example. However, in addition to this, precise driving in the carriage movement direction (main scanning direction) of the automatic component mounting apparatus and the image forming apparatus in PCB creation is described. It can also be applied to control.

  As described above, according to the present embodiment, the electrical components (LD11, PZT14) that can output an output signal corresponding to the ultra-small movement distance of the transport belt 4 and the output signal from the LD11 are accurately received. And an electrical component (PD11a) capable of analyzing the LD output result, and the analysis result can be fed back to the output signal of the transport motor 9. This enables ultra-precise control of the transport belt 4, thereby enabling color Deviation can be prevented, and the conveyor belt can be stopped at an intended place while performing fine adjustment.

  Further, since the control unit 6 recognizes the moving distance of the conveying belt from the number of pulses of the linear scale attached to the back of the conveying belt 4 and changes the amount of input current to the LD 11, the movement of the minute conveying belt is performed. The output can be output as a change in the PD output power (PD output) of the LD 11 and the oscillation frequency up to the amount.

  Further, since the control unit 6 analyzes the moving distance of the conveying belt 4 from the output signal to the conveying motor 6 that drives the conveying belt 4 and changes the input current amount to the LD 11, the movement of the minute conveying belt 4 is performed. The output can be output as a change in the PD output power (PD output) of the LD 11 and the oscillation frequency up to a certain amount.

  Further, the control unit 6 analyzes the moving distance of the conveying belt 4 from the gear that moves the conveying belt 4 and changes the input current amount to the LD 11, so that the amount of movement of the LD 11 is reduced to the minute moving amount of the conveying belt 4. PD output power (PD output) can be output as a change in oscillation frequency.

  Further, the control unit 6 recognizes the moving distance of the conveying belt 4 from the number of pulses of the linear scale 41 attached to the back of the conveying belt 4 and changes the voltage applied to the PZT 14. Up to the amount of movement, it can be output as a change in the frequency of the reflected light or transmitted light of the diffraction grating 13.

  Further, since the control unit 6 analyzes the movement distance of the conveyance belt 4 from the output signal to the conveyance motor 9 that drives the conveyance belt 4 and changes the voltage applied to the PZT 14, the movement amount of the minute conveyance belt is changed. Up to this time, it can be output as a change in the frequency of the reflected light or transmitted light of the diffraction grating 13.

  Further, since the control unit 6 analyzes the moving distance of the conveying belt 4 from the gear that moves the conveying belt 4 and changes the applied voltage to the PZT 14, the control unit 6 moves the diffraction grating 13 to the minute moving amount of the conveying belt 4. It can be output as a change in frequency of reflected light or transmitted light.

    Further, since the input current to the LD 11 varies depending on the moving distance of the conveying belt 4, the control unit 6 can recognize the moving distance of the conveying belt 4 from the output of the PD 11 a in the LD 11.

  Further, since the control unit 6 measures the moving distance of the conveying belt 4 by the change in the oscillation frequency of the LD 11 or the frequency change of the reflected light or transmitted light of the diffraction grating 13 by the homodyne frequency measurement method, the control unit 6 measures the frequency without the reference light, that is, the conveying belt. 4 movement distance measurements can be made.

  Further, the control unit 6 measures the moving distance of the conveyor belt 4 by measuring the change in the oscillation frequency of the LD 11 or the change in the frequency of the reflected light or transmitted light of the diffraction grating 13 by using a heterodyne frequency measurement method using reference light such as the optical frequency comb. In addition, it is possible to perform a frequency measurement that is even more precise than the homodyne frequency measurement method, that is, the movement distance measurement of the conveyor belt 4.

  In addition, the control unit 6 feeds back the belt movement distance analysis result to the conveyance motor 9 that drives the conveyance belt 4. At this time, the analysis of the belt movement distance directly measures the movement distance of the conveyance belt 4. Since they are equivalent, it is possible to compensate for the movement distance error of the conveyor belt 4 caused by variations in motor characteristics and performance.

  Further, the LD temperature setting unit 70 can directly measure the temperature of the LD 11 with the thermistor 71, and can always keep the temperature of the LD 11 constant with the Peltier element 72, and the set temperature can be freely changed. As a result, it is possible to compensate for changes in the characteristics of the LD 11 due to long-term use and variations in characteristics in LD manufacturing by adjusting the set temperature. At this time, since the frequency band can be used simultaneously, two heterodyne frequency measuring devices can simultaneously measure the paper transport belt moving distance and the carriage moving distance.

  Furthermore, when simultaneously measuring the transport belt moving distance and the carriage moving distance, the frequency band of the LD 11 used in the measurement is different, so that it is possible to use the frequency band of the non-overlapping portion on the optical frequency comb at the same time. The heterodyne frequency measuring device 16 can simultaneously measure the paper conveyance belt moving distance and the carriage moving distance.

  In this embodiment, an ink jet recording apparatus is taken as an example. However, in addition to this, it can be applied to an automatic component mounting apparatus for PCB creation, a driving apparatus mounted with a print head and precisely driven in the main scanning direction. .

1 is a diagram illustrating a schematic configuration of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a control configuration of the ink jet recording apparatus of FIG. 1. It is a flowchart which shows the process sequence of a control part. It is a figure which shows the structure which determines the electric current amount supplied to LD in LD current determination part using an encoder. It is a figure which shows the structure which determines the electric current amount supplied to LD from the control signal sent to a drive motor. It is a figure which shows the structure which measures the rotation speed of a drive motor and determines the electric current amount supplied to LD. It is a figure which shows the structure which determines the voltage applied to PZT from an encoder output. It is a figure which shows the structure which determines the voltage applied to PZT from the control signal sent to a drive motor. It is a figure which shows the structure which measures the rotation speed of a drive motor and determines the voltage applied to PZT. It is a figure which shows the structure which performs IV conversion based on the output signal of PD at the time of changing the electric current value to LD. It is a figure which shows the structure which replaces the moving distance of a conveyance belt with the frequency of light by receiving the output light of LD, or the transmitted light or reflected light from a diffraction grating, and measuring the frequency of light directly with a homodyne. The output light of LD or the transmitted light or reflected light from the diffraction grating is received, and the moving distance of the conveyor belt is replaced with the frequency of the light by measuring the frequency of the light directly with the heterodyne using the reference light including the optical frequency comb etc. It is a figure which shows the structure to measure. It is a flowchart which shows the control procedure which performs feedback control using PD output of LD. It is a flowchart which shows the control procedure which performs feedback control using the frequency of LD output light. It is a flowchart which shows the control procedure which performs feedback control using the frequency of diffraction grating reflected light or diffraction grating transmitted light. It is a figure which shows the correction circuit which correct | amends the dispersion | variation in LD characteristic. It is a figure which shows the state when simultaneously measuring a paper conveyance belt moving distance and a carriage moving distance simultaneously with one heterodyne frequency measuring device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 2 Inkjet head 3 Paper feed part 4 Paper conveyance part (conveyance belt)
DESCRIPTION OF SYMBOLS 5 Paper discharge part 6 Control part 7 Encoder sensor 8 Driver 9 Drive (conveyance) motor 10 Head control part
11 LD
11a PD
12 IV converter 13 Diffraction grating 14 PZT
DESCRIPTION OF SYMBOLS 15 Homodyne frequency measurement part 16 Heterodyne frequency measurement part 17 Optical frequency comb generator 41 Linear scale 61 LD current determination part 62 PZT application voltage determination part 70 LD temperature setting part 71 Thermistor 72 Peltier device

Claims (15)

Means for outputting the travel distance of the transport belt from sensors linked to the travel distance of the transport belt;
Means for reading the output signal output from the means for outputting in precise units;
Means for feeding back the output signal read by the reading means to a motor for driving the conveyor belt;
A conveyance control device comprising:   The means for feeding back to the motor driving the conveyor belt sends a stop signal to the motor when the signal obtained by the means for reading the output signal in precise units reaches a preset value, and the motor intends If not stopped at the position, the output operation from the means for outputting the movement distance of the conveyor belt, the read operation of the means for reading the output signal output from the output means in precise units, and the read output signal The conveyance control apparatus according to claim 1, wherein an operation of feeding back a feedback to a motor for driving the conveyance belt is repeated, and the conveyance belt can be stopped at a target position.   The means for outputting the moving distance of the conveyor belt analyzes an output signal from a sensor that reads the number of striped patterns drawn on the conveyor belt finely at equal intervals, and interlocks with the magnitude of the input current of the laser diode. The conveyance control apparatus according to claim 1, wherein:   The means for outputting the moving distance of the conveyor belt receives and analyzes the input signal to the motor in parallel, and is linked to the magnitude of the input current of the laser diode for detecting the moving distance. The conveyance control apparatus according to claim 1 or 2.   The means for outputting the moving distance of the conveyor belt is interlocked with a gear of the motor, and is interlocked with the magnitude of an input current of a laser diode for detecting the moving distance. Transport control device.   The means for outputting the moving distance of the conveyor belt analyzes an output signal from a sensor that reads the number of striped patterns drawn on the conveyor belt finely at equal intervals, and outputs a laser diode for detecting the moving distance 3. The conveyance control device according to claim 1, wherein the conveyance control device is interlocked with a magnitude of a voltage applied to a piezo actuator attached to a diffraction grating on which light is projected.   The means for outputting the moving distance of the conveyor belt receives and analyzes the input signal to the motor in parallel, and a piezo actuator attached to a diffraction grating onto which the output light of the laser diode for detecting the moving distance is projected The conveyance control device according to claim 1, wherein the conveyance control device is interlocked with the magnitude of the voltage applied to the substrate.   The means for outputting the moving distance of the conveyor belt is interlocked with the gear of the motor, and applies the voltage applied to the piezoelectric actuator attached to the diffraction grating onto which the output light of the laser diode for detecting the moving distance is projected. The conveyance control device according to claim 1, wherein the conveyance control device is interlocked with the size.   The means for reading the output signal in precise units reads the moving distance of the conveyor belt from a change in the value of a photodiode inside the laser diode for detecting the moving distance. The conveyance control apparatus as described.   The means for reading the output signal in precise units is the projection of the output light of the laser diode for detecting the moving distance, the transmitted light from the diffraction grating onto which the output light of the laser diode is projected, and the output light of the laser diode. 2. The method according to claim 1, wherein at least one of reflected light from the diffraction grating is received, and the frequency of light is directly measured by homodyne, whereby the moving distance of the conveyor belt is replaced with the frequency of light. Or the conveyance control apparatus of 2.   The means for reading the output signal in precise units is an output light of a laser diode for detecting the moving distance, a transmitted light from a diffraction grating onto which an output light of the laser diode for detecting the moving distance is projected, Receiving at least one of reflected light from a diffraction grating onto which an output light of a laser diode for detecting the moving distance is projected, and measuring the frequency of the light directly with a heterodyne using a reference light 3. The conveyance control apparatus according to claim 1, wherein the moving distance of the belt is measured by replacing it with the frequency of light.   The transport control apparatus according to claim 11, wherein the reference light includes an optical frequency comb.   The apparatus further comprises means for interlocking the movement position of the carriage holding the print head with the magnitude of the input current of the second laser diode for detecting the movement distance, and detects the movement distance used for the conveyance belt movement distance measurement. For measuring the carriage movement distance by the second laser diode for detecting the movement distance in a frequency band different from that of the first laser diode for simultaneous measurement of the paper conveyance belt movement distance and the carriage movement distance. The conveyance control apparatus according to claim 11, wherein the conveyance control apparatus is a heterodyne frequency measuring device.   6. The temperature setting of the laser diode is changed when the characteristics of the laser diode change or when the characteristics of the laser diode vary. The conveyance control apparatus as described. An image forming apparatus comprising the conveyance control device according to claim 1.

Images