JP2008179057A - Printer - Google Patents

Abstract

In a printer, deterioration of print quality due to carrier vibration is suppressed.
The printer controls the movement of the carrier holding the print head by controlling the rotation of the carrier motor. At this time, the rotation speed of the carrier motor is adjusted so that the moving speed of the carrier becomes a predetermined target speed. Feedback control. When the printer receives the print command (# 21), first, the carrier is moved at the same speed as the print speed by the print command, and a maintenance operation for preventing clogging of the print head is executed (# 23). It is determined whether or not the carrier is vibrated by this maintenance operation (# 24). Then, if vibration is generated in the carrier (YES in # 24), the printer 1 changes the driving parameter of the carrier motor (# 25), and feedbacks the rotation speed of the carrier motor using the changed driving parameter. The printing operation is executed under control (# 26).
[Selection] Figure 4

Description

  The present invention relates to a printer that prints an image by ejecting ink onto printing paper.

  2. Description of the Related Art Conventionally, there is a so-called inkjet printer that prints an image by ejecting ink onto printing paper. In this type of printer, generally, a printing operation for printing an image on printing paper is performed by ejecting ink from the printing head while moving a carrier holding the printing head. The carrier is slidably supported on the guide shaft, and is controlled to move through the carrier belt by the rotation of the carrier motor. The print head is adapted to eject the ink stored in the ink cartridge so that the ink cartridge moves with the print head and can be replaced when the stored ink is exhausted. It is detachably provided on the carrier.

  In such a printer, the carrier is moved at a predetermined target speed to perform a printing operation. However, when the carrier is moved, the carrier operation load (that is, the inertia due to the weight of the carrier and the weight of the print head and the ink cartridge held by the carrier, the frictional resistance between the carrier and the guide shaft, the carrier belt) Due to expansion and contraction, the carrier may vibrate (a phenomenon in which the actual moving speed of the carrier fluctuates from the target speed several times within a short time). When vibration is generated in the carrier, the print quality is lowered.

  Therefore, in such a printer, when the carrier is moved, the carrier speed and position are always (short time) so as to suppress the carrier vibration (that is, the carrier moving speed is always the target speed). There is one in which the movement speed of the carrier (that is, the rotation speed of the carrier motor) is feedback-controlled by proportional-integral control by monitoring periodically (at intervals). This feedback control by proportional-integral control is obtained as feedback information by measuring the actual velocity and actual position of the carrier periodically at a short time interval (for example, every 2 ms) while moving the carrier. Based on the measurement speed and measurement position of these carriers, the control amount of the carrier motor is calculated so that the moving speed of the carrier becomes the target speed by using the parameters of the proportional integral control, and according to this control quantity This is done by controlling the rotation speed of the carrier motor.

  In order to suppress carrier vibration, it is necessary to set proportional integral control parameters for feedback control of the carrier in consideration of the operating load of the carrier. Conventionally, the parameters of proportional-integral control are required to suppress carrier vibration in consideration of the carrier operation load for each model when designing a printer. In the conventional printer, the proportional-integral control parameter obtained at the time of design is preset as a fixed value, and the carrier moving speed is determined by proportional-integral control using the preset proportional-integral control parameter. Feedback control is provided.

On the other hand, before the printing operation is performed, the print head is reciprocated several times, and the supply current value of the carrier motor is corrected based on the difference between the actual speed of the carrier and the target speed for each reciprocation of the print head. By doing so, there is known a printer that obtains a supply current value of a carrier motor when the carrier moves at a target speed (see, for example, Patent Document 1). Also, in a printer that performs feedback control of the carrier speed during execution of the printing operation, if the carrier acceleration falls outside the allowable range, the printing operation is continued by changing the feedback control parameters during the printing operation. What was made is known (for example, refer patent document 2). In addition, in a printer that performs feedback control of the carrier speed during execution of a printing operation, the supply current of the carrier motor in the current printing operation is determined based on the difference between the actual speed of the carrier in the previous printing operation and the target speed. A device that corrects a PWM value is known (see, for example, Patent Document 3).
JP-A-11-216850 Japanese Patent Laid-Open No. 9-47057 Japanese Patent Laid-Open No. 9-202014

  By the way, the aging of the printer and the usage environment of the printer affect the operation load of the carrier. In order to suppress carrier vibration, it is necessary to set parameters for proportional-integral control for feedback control of the carrier in consideration of the operating load of the carrier as described above.

  However, in the above-described conventional printer, the parameter of the proportional-integral control for feedback control of the carrier is set as a fixed value and cannot be changed from the set value. For this reason, with conventional printers, when the printer is aged or when the printer is operated in a poor operating environment (high or low temperature environment, dust or dust accumulation). The preset proportional integral control parameter cannot be used, and the carrier may vibrate and the print quality may deteriorate.

  Thus, it is conceivable to change the parameters of proportional-integral control. Even when the printer is not aging or when the printer is not used in a poor operating environment, changes in the room temperature and humidity due to changes in the outside temperature in the morning, noon, and night, and changes in the weather, etc. The operation load of the carrier may be affected, and the change in the remaining amount of ink in the ink cartridge may affect the operation load of the carrier. Accordingly, it is necessary to be able to change the parameters of the proportional integral control so as to suppress the vibration of the carrier in response to the change in the indoor temperature and humidity and the change in the remaining amount of ink in the ink cartridge. .

  Note that the printer described in Patent Document 1 described above does not perform feedback control of the carrier speed during execution of a printing operation, and does not disclose anything about changing feedback control parameters. Therefore, in the printer described in Patent Document 1, as in the conventional printer, when the carrier is moving, the carrier is vibrated by the load of the carrier operation, and the print quality is lowered.

  Further, the printer described in Patent Document 2 described above performs feedback control on the moving speed of the carrier during execution of the printing operation, and changes the parameters of the feedback control. However, in the printer described in Patent Document 2, when the acceleration of the carrier falls outside the allowable range during the execution of the printing operation, the feedback control parameter is changed during the printing operation. If a change is necessary, the carrier movement control during printing will be performed with an inappropriate parameter until the parameter is changed, causing the carrier to vibrate and reducing the print quality. Will do.

  Further, the printer described in Patent Document 3 described above performs feedback control on the moving speed of the carrier during execution of the printing operation, but does not disclose anything about changing the feedback control parameter. Further, in the printer described in Patent Document 3, the PWM value of the supply current of the carrier motor in the current printing operation is corrected based on the previous printing operation, so the current printing operation from the previous printing operation is corrected. In some cases, the usage environment (for example, indoor temperature and humidity) may change over a long period of time, and in this case, the change in the usage environment will affect the operating load of the carrier, causing vibration in the carrier. As a result, the print quality is lowered.

  SUMMARY An advantage of some aspects of the invention is that it provides a printer that can suppress deterioration in print quality due to carrier vibration.

  In order to achieve the above object, a first aspect of the present invention is a sheet conveying means for conveying a print sheet, a print head for ejecting ink for printing an image on the print sheet, a carrier for holding the print head, and a carrier. A carrier motor that is rotationally controlled to move the carrier, a carrier moving means that receives the rotational force of the carrier motor and moves by moving the carrier motor, and a carrier speed measuring means that measures the moving speed of the carrier And a carrier position measuring means for measuring the position of the carrier and a control means for controlling the operation of the apparatus. The control means controls the movement of the carrier via the carrier moving means by controlling the rotation of the carrier motor. For printing by ejecting ink from the print head held by the carrier while moving the carrier. A printing operation for printing an image is performed, and the measurement speed and the carrier position measurement unit are used to measure the carrier speed so that the carrier moving speed becomes a predetermined target speed during the printing operation. In a printer that feedback-controls the rotation speed of the carrier motor based on a measurement position based on the measurement position, the control means receives the print instruction from the user and executes the print operation before performing the print operation. A maintenance operation is performed to prevent clogging of the print head by moving the ink to a predetermined maintenance position and ejecting ink from the print head at the maintenance position. It is moved at the target speed when performing the printing operation, and then measured by the carrier speed measurement means. Based on the comparison result between the measured speed and the target speed, execute the parameter adjustment operation to adjust the parameter of proportional integral control so as to suppress the error of the measured speed with respect to the target speed, and adjust the parameter during the printing operation Using the parameters adjusted by the operation, the rotation speed of the carrier motor is feedback controlled by proportional integral control, and the parameter adjustment operation is performed at the target speed when the carrier is printed when the carrier is moved in the maintenance operation. At this time, using the proportional component parameter and integral component parameter of the proportional integral control set at the initial stage, the measurement speed measured by the carrier velocity measuring means and the measurement position measured by the carrier position measuring means are used. The rotation speed of the carrier motor is controlled by proportional integral control. Whether or not the carrier vibrates based on the comparison result between the target speed and the measured speed per predetermined time measured by the carrier speed measuring means when the carrier is moved during maintenance operation. By adjusting the proportional component parameter and integral component parameter of proportional integral control so as to suppress the vibration generated in the carrier by suppressing the error of the measurement speed with respect to the target speed when the carrier is vibrating Is to be done.

  According to a second aspect of the present invention, there is provided a sheet conveying means for conveying a printing sheet, a printing head for ejecting ink for printing an image on the printing sheet, a carrier for holding the printing head, and a rotation control for moving the carrier. The carrier motor, the carrier moving means for transmitting the rotational force of the carrier motor and moving the carrier by the rotation of the carrier motor, the carrier speed measuring means for measuring the moving speed of the carrier, and measuring the position of the carrier Carrier position measuring means and control means for controlling the operation of the apparatus, and the control means controls the movement of the carrier via the carrier moving means by controlling the rotation of the carrier motor, while moving the carrier. A printing operation that prints an image on printing paper by ejecting ink from the print head held by the carrier Based on the measurement speed measured by the carrier speed measurement means and the measurement position measured by the carrier position measurement means so that the moving speed of the carrier becomes a predetermined target speed during the execution of the printing operation, In a printer that feedback-controls the rotation speed of the carrier motor by proportional integral control, the control means moves the carrier at the target speed when performing the printing operation before performing the printing operation, Sometimes, based on the comparison result between the measurement speed measured by the carrier speed measurement means and the target speed, a parameter adjustment operation is performed to adjust the parameters of proportional integral control so as to suppress the error of the measurement speed relative to the target speed, and printing During the operation, the rotation speed of the carrier motor is adjusted using the parameter adjusted by the parameter adjustment operation. In which a feedback control by proportional integral control.

  According to a third aspect of the present invention, in the printer according to the second aspect, before the printing operation is performed, the control unit moves the carrier to a predetermined maintenance position and ejects ink from the print head at the maintenance position. The maintenance operation for preventing clogging of the print head is executed, and the parameter adjustment operation moves the carrier at the target speed for performing the printing operation when moving the carrier in the maintenance operation. Based on the comparison result between the measurement speed measured by the carrier speed measurement means and the target speed, the proportional-integral control parameter is adjusted so as to suppress the error of the measurement speed with respect to the target speed.

  According to the first aspect of the present invention, when executing the printing operation, the proportional-integral control parameter for feedback control of the carrier is adjusted before the printing operation is performed, and the adjusted parameter is set during the execution of the printing operation. The rotation speed of the carrier motor (that is, the moving speed of the carrier) is feedback controlled by proportional integral control. Therefore, even when the printer is aged or when the printer is operated in a poor operating environment, or when there is a change in the room temperature or humidity, or when there is a change in the remaining amount of ink in the ink cartridge, The error of the actual speed (measurement speed) with respect to the target speed of the carrier can be suppressed to suppress the vibration of the carrier, thereby suppressing the deterioration of the print quality. Moreover, since the proportional-integral control parameters are adjusted before the printing operation is performed, it is possible to suppress the deterioration of the print quality by suppressing the carrier vibration immediately after the printing operation is started. In addition, the proportional-integral control parameter is adjusted when the printing operation is executed, so that the printer ages and the usage environment changes when the parameter is adjusted and when the printing operation is executed. Therefore, the deterioration of the print quality can be suppressed more reliably by suppressing the vibration of the carrier. Also, the maintenance operation is performed before the printing operation, and the proportional integration control parameter for feedback control of the carrier is adjusted using the carrier movement in the maintenance operation, so the proportional integration control parameter is adjusted. Therefore, it is not necessary to move the carrier separately only for the purpose, and the proportional-integral control parameter can be adjusted efficiently.

  According to the second aspect of the present invention, when the printing operation is executed, the proportional-integral control parameter for feedback control of the carrier is adjusted before the printing operation is performed, and the adjusted parameter is adjusted during the printing operation. The rotation speed of the carrier motor (that is, the moving speed of the carrier) is feedback controlled by proportional integral control. Therefore, even when the printer is aged or when the printer is operated in a poor operating environment, or when there is a change in the room temperature or humidity, or when there is a change in the remaining amount of ink in the ink cartridge, The error of the actual speed (measurement speed) with respect to the target speed of the carrier can be suppressed (thus, the vibration of the carrier can be suppressed), and thereby the deterioration of the print quality can be suppressed. In addition, since the proportional-integral control parameters are adjusted before the printing operation is performed, it is possible to suppress the deterioration of the print quality immediately after the printing operation is started. In addition, the proportional-integral control parameter is adjusted when the printing operation is executed, so that the printer ages and the usage environment changes when the parameter is adjusted and when the printing operation is executed. Therefore, it is possible to more reliably suppress the deterioration of print quality.

  According to the invention of claim 3, since the maintenance operation is performed before the printing operation is performed, the parameter of the proportional-integral control for feedback control of the carrier is adjusted using the movement of the carrier in the maintenance operation. It is not necessary to move the carrier separately only to adjust the proportional-integral control parameters, and the proportional-integral control parameters can be adjusted efficiently.

  Hereinafter, a printer according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of a printer. The printer 1 is a device that prints an image on the printing paper 2. The printer 1 is a so-called inkjet printer that prints an image by ejecting ink onto the printing paper 2.

  The printer 1 prints an image on the printing paper 2, a paper rest 3 on which the printing paper 2 is placed, a paper feed roller 4 a, a feed roller 4 b and an exit roller 4 c that are paper transporting means for transporting the printing paper 2. Print heads 5m and 5c, ink cartridges 6m and 6c for storing ink for printing an image on the printing paper 2, and print heads 5m and 5c are held and the print heads 5m and 5c are moved. Carrier 7 is provided. The printer 1 also includes a carrier belt 8 that is a carrier moving means for moving the carrier 7, a feed motor 9 that is rotationally controlled to rotate the paper feed roller 4 a, the feed roller 4 b, and the exit roller 4 c, and the carrier 7. A carrier motor 10 whose rotation is controlled so as to move the encoder, an encoder 11 for measuring the moving speed and position of the carrier 7, and the like.

  One or a plurality of printing papers 2 are stacked, and the lower end side thereof is inserted into the paper feeding port 21 of the housing 20 and placed on the paper rest 3. The paper feed roller 4a takes the printing paper 2 placed on the paper rest 3 into the housing 20 and conveys it to the feed roller 4b. The feed roller 4b conveys the printing paper 2 conveyed from the paper feeding roller 4a to the exit roller 4c through the lower portions of the print heads 5m and 5c. The exit roller 4c is the printing paper 2 conveyed by the feed roller 4b. Is further conveyed and discharged from the paper discharge port 22 to the outside of the housing 20. The feed roller 4a, the feed roller 4b, and the exit roller 4c are controlled to rotate by a rotation of the feed motor 9 via a roller driving mechanism including a gear (not shown).

  The print heads 5 m and 5 c are ink jet print heads that eject ink to print an image on the printing paper 2. The print head 5m is a monochrome print head, and the print head 5c is a color print head. The ink cartridge 6m is a monochrome ink cartridge and stores monochrome (black) ink to be ejected from the print head 5m. The ink cartridge 6c is a color ink cartridge and stores color (cyan, magenta, yellow) ink to be ejected from the print head 5c.

  The monochrome print head 5m is provided integrally with the monochrome ink cartridge 6m, and ejects monochrome ink stored in the monochrome ink cartridge 6m. The color print head 5c is provided integrally with the color ink cartridge 6c, and ejects the color ink stored in the color ink cartridge 6c.

  The ink cartridges 6m and 6c are detachably held on the carrier 7 so that they can be replaced when the stored ink runs out. The print head 5m is attached to and detached from the carrier 7 together with the ink cartridge 6m and is exchanged together with the ink cartridge 6m. The print head 5c is attached to and detached from the carrier 7 together with the ink cartridge 6c and exchanged together with the ink cartridge 6c. The print heads 5m and 5c and the ink cartridges 6m and 6c are mounted and held on the carrier 7 with the print heads 5m and 5c facing down so as to eject ink downward from the print heads 5m and 5c.

  The carrier 7 is slidably supported by the guide shafts 31 and 32, and is guided by the guide shafts 31 and 32 so as to reciprocate in the direction in which the guide shafts 31 and 32 extend. The guide shafts 31, 32 extend above the printing paper 2 conveyed by the feed roller 4b and the exit roller 4c in a direction parallel to the printing surface of the printing paper 2 and orthogonal to the conveyance direction of the printing paper 2. .

  The carrier belt 8 is wound around the carrier motor 10 and the pulley 39, and is stretched between the carrier motor 10 and the pulley 39 substantially in parallel with the direction in which the guide shafts 31 and 32 extend. The rotational force is transmitted and the carrier motor 10 is operated by the rotational force. The back of the carrier 7 is fixedly connected to the carrier belt 8. That is, the carrier belt 8 operates by the rotation of the carrier motor 10 to move the carrier 7 in the direction in which the guide shafts 31 and 32 extend.

  In other words, the carrier 7 is controlled to move in the direction in which the guide shafts 31 and 32 extend via the carrier belt 8 by the rotation of the carrier motor 10 and above the printing paper 2 conveyed by the feed roller 4b and the exit roller 4c. Are reciprocated along the printing surface of the printing paper 2 in a direction perpendicular to the conveyance direction of the printing paper 2. The print heads 5m and 5c and the ink cartridges 6m and 6c held by the carrier 7 move together with the carrier 7 as the carrier 7 moves.

  The encoder 11 includes an encoder strip 12 on which a light and dark pattern with a predetermined pitch is formed, an optical strip sensor 13 that receives reflected light from the encoder strip 12, and the like. The encoder strip 12 is provided on the guide shaft 31, and a light and dark pattern with a predetermined pitch is formed along the movement path of the carrier 7. The strip sensor 13 is provided on the back of the carrier 7 and moves together with the carrier 7. The encoder 11 receives reflected light from the light / dark pattern of the encoder strip 12 by the strip sensor 13 and outputs a carrier movement amount detection signal having a pulse number proportional to the movement amount of the carrier 7 based on the change in the received light intensity. .

  The printer 1 having such a configuration controls the conveyance of the printing paper 2 by the feed roller 4a, the feed roller 4b, and the exit roller 4c by controlling the rotation of the feed motor 9, and also controls the rotation of the carrier motor 10. Thus, the movement of the carrier 7 (that is, the print heads 5m and 5c) is controlled via the carrier belt 8.

  The printer 1 conveys the printing paper 2 and prints an image on the printing paper 2 by ejecting ink from the print heads 5 m and 5 c while moving the carrier 7 above the conveyed printing paper 2. A printing operation is performed. Further, the printer 1 performs a maintenance operation for preventing the print heads 5m and 5c from being clogged. The maintenance operation is performed by ejecting ink from the color print head 5c at the color maintenance position Xc and ejecting ink from the monochrome print head 5m at the monochrome maintenance position Xm.

  The color maintenance position Xc is set at a position on the left side (opposite to the side on which the carrier motor 10 is disposed) of the printing paper 2 on the conveyance path, and the monochrome maintenance position Xm is a printing paper. It is set at a location on the right side (the side where the carrier motor 10 is arranged) from the second conveyance path. Note that the carrier 7 is placed on standby at the home position Xo when the printing operation or the maintenance operation is not performed. The home position Xo is set on the left side of the color maintenance position Xc.

  FIG. 2 shows an electrical block configuration of the printer 1. In addition to the above-described configuration, the printer 1 includes a control unit 41 including a CPU, ROM, RAM, and the like for controlling the operation of the printer 1, a feed motor drive circuit 42, a carrier motor drive circuit 43, and a head drive circuit. 44, a carrier speed calculation unit 45, a carrier position calculation unit 46, a parameter memory 47, an external device connection unit 48, and a work memory 49. Firmware and various data for controlling the operation of the printer 1 are stored in the ROM of the control unit 41.

  The printer 1 can be used by being connected to a PC (personal computer) 60 which is an external device. That is, a printer driver 70 for controlling the operation of the printer 1 via the PC 60 is installed in the PC 60 (stored in the storage unit of the PC 60). The printer driver 70 installed in the PC 60 causes the PC 60 to be installed. Various operations of the printer 1 are controlled via the control.

  The feed motor drive circuit 42 rotates the feed motor 9 under the control of the control unit 41. When the feed motor 9 is driven to rotate, the paper feed roller 4a, the feed roller 4b, and the exit roller 4c rotate, and the printing paper 2 is conveyed. The carrier motor drive circuit 43 rotationally drives the carrier motor 10 under the control of the control unit 41. When the carrier motor 10 is rotationally driven, the carrier 7 is moved via the carrier belt 8, and the print heads 5m and 5c and the ink cartridges 6m and 6c are moved. The head drive circuit 44 drives the print heads 5m and 5c under the control of the control unit 41, and ejects ink from the print heads 5m and 5c.

  The carrier speed calculation unit 45 calculates (measures) the movement speed of the carrier 7 based on the carrier movement amount detection signal output from the encoder 11. The encoder 11 and the carrier speed calculation unit 45 constitute a carrier speed measuring means for measuring the moving speed of the carrier 7. The carrier speed calculation unit 45 calculates the moving speed of the carrier 7 every 2 ms and outputs a carrier speed signal indicating the moving speed of the carrier 7. The carrier speed signal output from the carrier speed calculation unit 45 is input to the control unit 41.

  The carrier position calculation unit 46 calculates (measures) the position of the carrier 7 based on the carrier movement amount detection signal output from the encoder 11. The encoder 11, the carrier position calculation unit 46, etc. constitute carrier position measuring means for measuring the position of the carrier 7. The carrier position calculation unit 46 calculates the position of the carrier 7 every 2 ms and outputs a carrier position signal indicating the position of the carrier 7. The carrier position signal output from the carrier position calculation unit 46 is input to the control unit 41.

  The parameter memory 47 is a memory that stores a proportional component parameter and an integral component parameter of proportional integral control for feedback control of the moving speed of the carrier 7 (rotational speed of the carrier motor 10) by proportional integral control. The parameter memory 47 is set as a proportional component parameter and an integral component parameter of proportional integral control with parameters that are initially set (parameters determined at the design so that the carrier 7 does not vibrate when the carrier 7 is moved). Pre-stored. Further, the parameter memory 47 stores parameters adjusted by a parameter adjustment operation described later under the control of the control unit 41 as the proportional component parameter and integral component parameter of the proportional-integral control.

  The external device connection unit 48 communicates with the PC 60 and is connected to the PC 60 via a USB cable. The external device connection unit 48 transmits / receives various data to / from the PC 60 via the USB cable under the control of the control unit 41. The work memory 49 is controlled by the control unit 41, various data received from the PC 60, various data for controlling the operation of the printer 1, and various types of data performed by the control unit 41 for controlling the operation of the printer 1. The result of the arithmetic processing is temporarily stored.

  The controller 41 controls the conveyance of the printing paper 2 via the paper feed roller 4a, the feed roller 4b, and the exit roller 4c by controlling the rotation drive of the feed motor 9 by the feed motor drive circuit 42. Further, the control unit 41 controls the rotation of the carrier motor 10 by the carrier motor driving circuit 43 to move the carrier 7 via the carrier belt 8 (that is, the print heads 5m and 5c held by the carrier 7). Control). Further, the control unit 41 controls the ejection of ink from the print heads 5 m and 5 c by the head drive circuit 44.

  Here, the movement control of the carrier 7 will be described. As described above, the carrier 7 is controlled to move through the carrier belt 8 by the rotation of the carrier motor 10. As the carrier motor 10, a DC motor is used in which the rotation speed changes depending on the magnitude of the supplied drive current, and the rotation direction changes depending on the polarity of the supplied drive current. The rotation speed of the carrier motor 10 increases as the drive current increases, and decreases as the supplied drive current decreases. The carrier motor 10 is driven by a carrier motor drive circuit 43.

  The carrier motor drive circuit 43 drives the carrier motor 10 by PWM. That is, the carrier motor drive circuit 43 PWM modulates the drive current of the carrier motor 10 and supplies the PWM modulated drive current to the carrier motor 10. As the duty ratio of PWM drive (duty ratio of PWM-modulated drive current) increases, the drive current supplied to the carrier motor 10 increases and the rotational speed of the carrier motor 10 increases, while the PWM drive duty ratio increases. As the duty ratio decreases, the drive current supplied to the carrier motor 10 decreases and the rotation speed of the carrier motor 10 decreases. The PWM drive of the carrier motor 10 by the carrier motor drive circuit 43 is controlled by the control unit 41.

  The control unit 41 gives a PWM output for controlling the PWM driving of the carrier motor 10 to the carrier motor driving circuit 43. The carrier motor drive circuit 43 PWM drives the carrier motor 10 based on the PWM output given from the control unit 41. That is, the carrier motor drive circuit 43 PWM modulates the drive current of the carrier motor 10 with the duty ratio of the PWM output given from the control unit 41 and supplies the PWM modulated drive current to the carrier motor 10.

  That is, the control unit 41 provides the carrier motor drive circuit 43 with a PWM output, thereby causing the carrier motor drive circuit 43 to drive the PWM with the duty ratio of the PWM output, and thereby the duty ratio of the PWM output. The carrier motor 10 is rotated at a rotational speed corresponding to the above, and the carrier 7 is moved. Then, the control unit 41 controls the PWM drive of the carrier motor 10 by the carrier motor drive circuit 43 by controlling the duty ratio of the PWM output given to the carrier motor drive circuit 43, and thereby the rotation speed of the carrier motor 10. To control the moving speed of the carrier 7.

  Further, when the control unit 41 moves the carrier 7 in the printing operation and the maintenance operation, the moving speed of the carrier 7 calculated by the carrier speed calculating unit 45 (so that the moving speed of the carrier 7 becomes a predetermined target speed ( Based on the measurement speed) and the position of the carrier 7 (measurement position) calculated by the carrier position calculation unit 46, the moving speed of the carrier 7 (that is, the rotation speed of the carrier motor 10) is feedback-controlled by proportional integral control.

  FIG. 3 shows a flowchart of feedback control by proportional integral control of the moving speed of the carrier 7. As described above, the control unit 41 provides the carrier motor drive circuit 43 with a PWM output, thereby rotating the carrier motor 10 at a rotational speed corresponding to the duty ratio of the PWM output to move the carrier 7.

  When the control unit 41 moves the carrier 7, the movement speed (measurement speed) of the carrier 7 calculated by the carrier speed calculation unit 45 and the position (measurement position) of the carrier 7 calculated by the carrier position calculation unit 46. Is obtained as feedback information (# 11), and the control amount M of the carrier motor 10 is calculated based on the feedback information (# 12).

  At this time, the control unit 41 sets the parameter memory 47 based on the deviation between the target speed of the carrier 7 and the measurement speed (actual movement speed) and the deviation between the target position of the carrier 7 and the measurement position (actual position). The control amount M of the carrier motor 10 is calculated using the proportional component parameter and the integral component parameter of the proportional integral control stored in. The control amount M of the carrier motor 10 is ΔV for the deviation between the target speed of the carrier 7 and the measurement speed, ΔX for the deviation between the target position of the carrier 7 and the measurement position, Kp for the proportional component parameter of the proportional integral control, and proportional integral control. Is calculated by M = Kp × ΔV + Ki × ΔX.

  And the control part 41 controls the carrier motor 10 by the PWM output according to this control amount M (# 13). That is, the control unit 41 controls the duty ratio of the PWM output given to the carrier motor drive circuit 43 according to the control amount M, thereby controlling the rotational speed of the carrier motor 10 and moving the carrier 7. To control.

  The control unit 41 repeats the processes after # 11 while moving the carrier 7. As described above, the calculation of the moving speed of the carrier 7 by the carrier speed calculation unit 45 and the calculation of the position of the carrier 7 by the carrier position calculation unit 46 are performed every 2 ms. That is, the control unit 41 performs the processes of # 11 to # 13 every 2 ms while moving the carrier 7, and controls the moving speed of the carrier 7 (rotational speed of the carrier motor 10) by proportional integral control. Feedback control. The carrier 7 is controlled to move in this way under the control of the control unit 41.

  The printer driver 70 receives a user operation on the PC 60 and issues a print instruction to the printer 1. When the print instruction is issued to the printer 1, the printer driver 70 issues a print command for printing an image. Send to printer 1. The print command includes print image data representing an image to be printed, print speed data indicating the print speed of the image (the moving speed of the carrier 7 when printing the image), and the like.

  When the control unit 41 of the printer 1 receives a print command from the printer driver 70 (that is, receives a print instruction from the user), the control unit 41 executes a print job based on the print command. For the print job, in order to control the printing operation for printing an image on the printing paper 2, the maintenance operation for preventing clogging of the print heads 5m and 5c, and the moving speed of the carrier 7 (rotational speed of the carrier motor 10). The proportional component parameter of the proportional integral control and the parameter adjusting operation for adjusting the integral component parameter are included.

  In the printing operation, the printing paper 2 is transported based on the print image data, the printing speed data, and the like included in the printing command, and the print heads 5m and 5c are moved while the carrier 7 is moved above the transported printing paper 2. This is done by ejecting ink. The printing operation is performed after the maintenance operation and the parameter adjustment operation.

  In the maintenance operation, the carrier 7 is moved from the home position Xo to the color maintenance position Xc, and ink is ejected from the color print head 5c at the color maintenance position Xc. This is performed by moving the ink from the maintenance position Xc to the monochrome maintenance position Xm and ejecting ink from the monochrome print head 5m at the monochrome maintenance position Xm. The maintenance operation is performed before the printing operation is performed.

  In the parameter adjustment operation, the carrier 7 is moved at the target speed when the printing operation is performed, and the measurement with respect to the target speed is performed based on the comparison result between the measurement speed and the target speed measured by the carrier speed calculation unit 45 at that time. The proportional component parameter and the integral component parameter of the proportional integral control are calculated so as to suppress the speed error, and the calculated proportional component parameter and the integral component parameter of the proportional integral control are stored in the parameter memory 47. The parameter adjustment operation is performed before the printing operation, and is performed using the movement of the carrier 7 in the maintenance operation.

  FIG. 4 shows a flowchart of a print job of the printer 1. When the control unit 41 receives a print command from the printer driver 70 (YES in # 21), first, an image printing speed when performing a printing operation from the print command (moving speed of the carrier 7 when printing an image). Is confirmed (# 22). As described above, the print command includes print image data representing an image to be printed, print speed data indicating the print speed of the image (the moving speed of the carrier 7 when printing the image), and the like. The control unit 41 confirms the printing speed of the image based on the printing speed data included in the printing command, and sets the printing speed of the image as the target speed of the carrier 7 when performing the printing operation. .

  Subsequently, the control unit 41 performs the maintenance operation by moving the carrier 7 at the same speed as the image printing speed confirmed in # 22 (# 23). That is, when moving the carrier 7 in the maintenance operation, the control unit 41 moves the carrier 7 at the target speed for performing the printing operation. At this time, the control unit 41 feedback-controls the moving speed of the carrier 7 (the rotational speed of the carrier motor 10) by proportional integral control as described above. At this time, the control unit 41 uses the proportional component parameter and the integral component parameter of the proportional integral control that are stored in advance in the parameter memory 47 (that is, set in the initial stage) and proportionally adjusts the moving speed of the carrier 7. Feedback control is performed by integral control.

  And the control part 41 judges whether the vibration has generate | occur | produced in the carrier 7 by maintenance operation | movement (# 24). Note that the vibration of the carrier 7 refers to a phenomenon in which the actual moving speed of the carrier 7 fluctuates from the target speed several times within a short time. Whether the carrier 7 is vibrating or not is determined based on the measured speed (actual moving speed) and the target speed every 2 ms calculated by the carrier speed calculating unit 45 when the carrier 7 is moved in the maintenance operation. For example, if the measurement speed of the carrier 7 fluctuates from the target speed beyond the specified value more than once in 200 ms, the carrier 7 is vibrated. to decide.

  Here, if vibration is generated in the carrier (YES in # 24), the control unit 41 changes the proportional component parameter and the integral component parameter of the proportional integral control for controlling the moving speed of the carrier 7 (#). 25). That is, the control unit 41 calculates the proportional component parameter and the integral component parameter of the proportional integral control so as to suppress the vibration generated in the carrier 7 by suppressing the error of the measurement speed with respect to the target speed of the carrier 7, and the calculated proportionality The proportional component parameter and the integral component parameter of the integral control are stored in the parameter memory 47. If no vibration is generated in the carrier (NO in # 24), the control unit 41 does not change the proportional component parameter and the integral component parameter of the proportional integral control. The parameter adjustment operation is performed by the processes of # 23 to # 25.

  Subsequently, the control unit 41 executes a printing operation (# 26). That is, the control unit 41 executes the printing operation at the image printing speed confirmed in # 22. At this time, the control unit 41 feedback-controls the moving speed of the carrier 7 by proportional-integral control as described above. At this time, when the control unit 41 determines that vibration is generated in the carrier 7 in # 24 (that is, when vibration is generated in the carrier 7 in the maintenance operation of # 23), When the moving speed of the carrier 7 is feedback-controlled by proportional-integral control using the parameter changed in # 25, on the other hand, if it is determined in 24 that no vibration has occurred in the carrier 7 (that is, the maintenance of # 23 above) When no vibration is generated in the carrier 7 during operation), the moving speed of the carrier 7 is controlled by proportional integral control using parameters stored in advance in the parameter memory 47 (that is, initially set). Feedback control.

  When the printing operation is finished, the control unit 41 deletes the parameter changed (stored in the parameter memory 47) in # 25 (# 27). Then, the control unit 41 ends the print job.

  According to the printer 1 having such a configuration, when executing the printing operation, the parameters of the proportional-integral control for feedback control of the carrier 7 are adjusted before the printing operation is performed, and the parameters are adjusted during the execution of the printing operation. The rotational speed of the carrier motor 10 (that is, the moving speed of the carrier 7) is feedback-controlled by proportional-integral control using the parameters. Therefore, even when the printer 1 is aged or when the printer 1 is operated in a poor use environment, when the room temperature or humidity changes, or the ink remaining amount in the ink cartridges 6m and 6c changes. Even in such a case, the error of the actual speed (measurement speed) with respect to the target speed of the carrier 7 can be suppressed, and the vibration of the carrier 7 can be suppressed, whereby deterioration of the print quality can be suppressed.

  Moreover, since the proportional-integral control parameters are adjusted before the printing operation is performed, it is possible to suppress the deterioration of the printing quality by suppressing the vibration of the carrier 7 immediately after the start of the printing operation. Further, since the proportional-integral control parameter is adjusted when the printing operation is executed, the printer 1 is aged or the usage environment is changed depending on whether the parameter is adjusted or when the printing operation is executed. Therefore, it is possible to more reliably suppress the vibration of the carrier 7 and suppress the deterioration of the print quality.

  Further, since the maintenance operation is performed before the printing operation is performed and the parameter of the proportional integration control for feedback control of the carrier 7 is adjusted using the movement of the carrier 7 in the maintenance operation, the parameter of the proportional integration control is adjusted. Therefore, it is not necessary to move the carrier 7 separately only for adjusting the parameter, and the proportional-integral control parameter can be adjusted efficiently.

  In addition, this invention is not restricted to the structure of the said embodiment, A various deformation | transformation is possible. For example, the parameter changed by the parameter adjustment operation (stored in the parameter memory) may be used as a parameter for moving the carrier in the maintenance operation of the next print job without being deleted. The movement speed and position of the carrier may be measured based on the rotation amount of the scan motor instead of measuring based on the movement amount of the carrier. The printer is not limited to printing an image based on a print command received from a printer driver installed in an external device. For example, the printer includes an image reading unit and is based on data obtained by reading an image by the image reading unit. An image may be printed.

1 is a partially broken perspective view showing a schematic configuration of a printer according to an embodiment of the present invention. FIG. 2 is an electrical block configuration diagram of the printer. 6 is a flowchart showing feedback control of a carrier moving speed of the printer. 6 is a flowchart showing a print job of the printer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 2 Printing paper 3 Paper rest 4a Paper feed roller 4b Feed roller 4c Exit roller 5m, 5c Print head 6m, 6c Ink cartridge 7 Carrier 8 Carrier belt 9 Feed motor 10 Carrier motor 11 Encoder 12 Encoder strip 13 Strip sensor 20 Housing DESCRIPTION OF SYMBOLS 21 Paper feed port 22 Paper discharge port 31, 32 Guide shaft 39 Pulley 41 Control part 42 Feed motor drive circuit 43 Carrier motor drive circuit 44 Head drive circuit 45 Carrier speed calculation part 46 Carrier position calculation part 47 Parameter memory 48 External apparatus connection part 49 Work memory 60 PC (Personal computer)
70 Printer driver

Claims (3)

A paper conveying means for conveying the printing paper, a printing head for ejecting ink to print an image on the printing paper, a carrier for holding the printing head, and a carrier motor that is rotationally controlled to move the carrier; A carrier moving means for transmitting the rotational force of the carrier motor and operating by the rotation of the carrier motor to move the carrier; a carrier speed measuring means for measuring the moving speed of the carrier; and measuring the position of the carrier. Carrier position measuring means, and control means for controlling the operation of the apparatus,
The control means includes
By controlling the rotation of the carrier motor, the carrier is controlled to move through the carrier moving means,
A printing operation for printing an image on printing paper is performed by ejecting ink from the print head held by the carrier while moving the carrier,
Based on the measurement speed measured by the carrier speed measurement means and the measurement position measured by the carrier position measurement means so that the movement speed of the carrier becomes a predetermined target speed during the execution of the printing operation, In a printer that feedback-controls the rotation speed of the carrier motor by proportional-integral control,
The control means includes
When executing the printing operation in response to a printing instruction from the user,
Before performing the printing operation, the carrier is moved to a predetermined maintenance position, and ink is ejected from the print head at the maintenance position, thereby performing a maintenance operation for preventing the print head from being clogged. And
Further, before performing the printing operation, the carrier is moved at a target speed when the printing operation is performed, and a comparison result between the measurement speed measured by the carrier speed measurement unit and the target speed is obtained. Based on this, a parameter adjustment operation is performed to adjust the parameters of the proportional-integral control so as to suppress an error in the measurement speed with respect to the target speed,
During the execution of the printing operation, using the parameter adjusted by the parameter adjustment operation, feedback control of the rotation speed of the carrier motor by proportional integral control,
The parameter adjustment operation is:
When the carrier is moved in the maintenance operation, the carrier is moved at a target speed for performing the printing operation, and at this time, the proportional component parameter and the integral component parameter of the proportional integral control which are initially set are used. Feedback control of the rotation speed of the carrier motor by proportional integral control based on the measurement speed measured by the carrier speed measurement means and the measurement position measured by the carrier position measurement means,
Whether or not vibration is generated in the carrier based on the comparison result between the target speed and the measurement speed measured every predetermined time when the carrier is moved in the maintenance operation. Determine whether
Adjusting the proportional component parameter and the integral component parameter of the proportional integral control so as to suppress the vibration generated in the carrier by suppressing the error of the measurement speed with respect to the target speed when the carrier is vibrating. Done by
A printer characterized by that. A paper conveying means for conveying the printing paper, a printing head for ejecting ink to print an image on the printing paper, a carrier for holding the printing head, and a carrier motor that is rotationally controlled to move the carrier; A carrier moving means for transmitting the rotational force of the carrier motor and operating by the rotation of the carrier motor to move the carrier; a carrier speed measuring means for measuring the moving speed of the carrier; and measuring the position of the carrier. Carrier position measuring means, and control means for controlling the operation of the apparatus,
The control means includes
By controlling the rotation of the carrier motor, the carrier is controlled to move through the carrier moving means,
Executing a printing operation for printing an image on a printing paper by ejecting ink from the print head held by the carrier while moving the carrier;
Based on the measurement speed measured by the carrier speed measurement means and the measurement position measured by the carrier position measurement means so that the movement speed of the carrier becomes a predetermined target speed during the execution of the printing operation, In a printer that feedback-controls the rotation speed of the carrier motor by proportional-integral control,
The control means includes
When performing the printing operation,
Before performing the printing operation, the carrier is moved at a target speed when the printing operation is performed, and based on a comparison result between the measurement speed measured by the carrier speed measurement unit and the target speed at that time. Executing a parameter adjustment operation for adjusting the parameters of the proportional-integral control so as to suppress an error in the measurement speed with respect to the target speed,
During the execution of the printing operation, feedback control of the rotation speed of the carrier motor is performed by proportional integral control using the parameter adjusted by the parameter adjustment operation.
A printer characterized by that. The control means includes
Before performing the printing operation, the carrier is moved to a predetermined maintenance position, and ink is ejected from the print head at the maintenance position, thereby performing a maintenance operation for preventing the print head from being clogged. And
The parameter adjustment operation is:
When the carrier is moved in the maintenance operation, the carrier is moved at a target speed when the printing operation is performed, and a comparison result between the measurement speed measured by the carrier speed measurement unit and the target speed at that time Is performed by adjusting the parameter of the proportional-integral control so as to suppress the error of the measurement speed with respect to the target speed,
The printer according to claim 2.

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