JP2005014297A - Method and device for controlling moving speed of inkjet head, and inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for controlling a moving speed of an inkjet head whereby the inkjet head can be appropriately moved to cope with characteristics variation and load of each carriage motor, and to provide a moving speed controlling device and an inkjet printer. <P>SOLUTION: There are set a target movement control process of controlling an acceleration movement of the inkjet head 61 so that the moving speed becomes a set target speed; a speed detection process of detecting a reach moving speed Vr of the inkjet head 61 at a shift position from the acceleration movement to a uniform velocity movement; a table selection process of selecting on the basis of the reach moving speed Vr, one speed control table T from a plurality of speed control tables T which preliminarily set moving speeds of at least the uniform velocity movement and a deceleration movement; and a table movement control process of controlling the movement of the inkjet head 61 on the basis of the selected one speed control table T. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a moving speed control method, a moving speed control apparatus, and an ink jet printer for an ink jet head that controls a moving speed of an ink jet head using a control motor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a printing apparatus such as an inkjet printer, printing (recording) is performed by ejecting ink to a recording head while scanning the recording head (inkjet head) along a recording material (printing object) via a carriage. It is carried out. A carriage motor (control motor) for moving the carriage is connected to the carriage, and the scanning speed of the recording head is controlled by controlling the carriage motor.
[0003]
The carriage motor is controlled in accordance with a carriage motor drive control table prepared in advance. In order to improve print quality, the scanning speed of the recording head during printing is constant (constant), and the carriage motor drive control table accelerates the carriage from the stop state to the constant speed state. A ramp-up region for moving while moving and a ramp-down region for decelerating from a constant speed state to a stop state are provided (for example, see Patent Document 1).
[0004]
[Patent Document 1]
JP-A-9-95023 (pages 3-6, FIG. 7)
[0005]
[Problems to be solved by the invention]
As described above, when controlling the carriage motor using the drive control table, it is necessary to consider manufacturing variations in characteristics of the carriage motor itself (for example, rise characteristics and load characteristics). In order to reliably perform motor drive control, a drive control table has been created assuming a carriage motor with the worst conditions. Therefore, in the conventional printing apparatus, all the carriage motors are driven in accordance with the characteristics of the carriage motor having the worst conditions, so that the scanning speed of the inkjet head during printing is slowed down and the printing time is lengthened. It was.
[0006]
In addition, it is known that a motor such as a commutator motor constituting a carriage motor has a reduced rotational speed when the load applied to the motor increases (overloads). When the load applied to the carriage motor fluctuates, the conventional printing apparatus drives the carriage motor using a drive control table created assuming the maximum load applied to the carriage motor in order to stably scan the recording head. I was in control. That is, in the conventional printing apparatus, even if the carriage motor is not subjected to the maximum load, the carriage motor is driven and controlled at the maximum rotation speed of the motor that can be controlled at the maximum load, so the printing speed is reduced. Occurs.
[0007]
Accordingly, the present invention provides a moving speed control method, a moving speed control apparatus, and an ink jet printer for an ink jet head capable of appropriately moving the ink jet head in accordance with variations in characteristics and loads of individual carriage motors. The purpose is that.
[0008]
[Means for Solving the Problems]
The present invention uses a control motor to accelerate and move the inkjet head in order to perform main scanning for selectively ejecting and driving the inkjet head while moving the inkjet head relative to the print object. In the moving speed control method of the inkjet head that moves at a high speed and further decelerates, a target movement control process that controls the acceleration movement of the inkjet head so that the movement speed becomes the set target speed, and from the accelerated movement to the constant speed movement A speed detection step for detecting the arrival movement speed of the ink jet head at the transition position of the ink jet, and at least one speed control from a plurality of speed control tables in which at least constant speed movement and deceleration movement speed are determined based on the arrival movement speed Table selection process for selecting a table and 1 speed selected in the table selection process Based on your table, it characterized by comprising at least a table movement control step of controlling the constant speed movement and the deceleration movement of the ink jet head.
[0009]
In addition, the present invention provides a control motor for accelerating and moving the inkjet head in order to perform main scanning for selectively discharging and driving the inkjet head while moving the inkjet head with respect to the print object. In the inkjet head moving speed control device that moves at a constant speed and further decelerates, a target movement control means for controlling the acceleration movement of the inkjet head so that the movement speed becomes the set target speed, and a constant speed from the acceleration movement. Based on the speed detection means for detecting the arrival movement speed of the inkjet head at the movement transition position, and a plurality of speed control tables in which at least constant movement speeds and deceleration movement speeds are determined based on the arrival movement speed, Table selection means for selecting the speed control table and 1 selected by the table selection means Based on the speed control table, characterized by comprising at least a table movement control means for controlling the constant speed movement and the deceleration movement of the ink jet head.
[0010]
According to these configurations, the speed of one of the plurality of speed control tables is determined based on the arrival speed of the ink-jet head at the transition position from the acceleration movement to the constant-speed movement of the ink-jet head that accelerates to reach the target speed. A control table is selected. Therefore, even if the performance of each control motor varies, and even if the reaching movement speed of the inkjet head differs depending on the control motor, one speed control table is selected from a plurality of speed control tables according to the performance of each control motor. The speed of the inkjet head can be controlled by selecting.
[0011]
When a plurality of control tables can be selected, in order to increase the scanning speed of the inkjet head, the fastest speed control table is selected from the selectable speed control tables, and the inkjet head is scanned at a higher speed. It is possible to make it.
[0012]
The present invention uses a control motor to accelerate and move the inkjet head in order to perform main scanning for selectively ejecting and driving the inkjet head while moving the inkjet head relative to the print object. In the moving speed control method of the inkjet head that moves at a high speed and further decelerates, a target movement control process that controls the acceleration movement of the inkjet head so that the movement speed becomes the set target speed, and from the accelerated movement to the constant speed movement A speed detection step for detecting the arrival movement speed of the inkjet head at the transition position, a table creation step for creating a speed control table that defines at least the movement speeds of the constant speed movement and the deceleration movement based on the arrival movement speed, and a table Based on the speed control table created in the creation process, at least the ink And table movement control step of controlling the constant speed movement and the deceleration movement of Ettoheddo, characterized by comprising a.
[0013]
In addition, the present invention provides a control motor for accelerating and moving the inkjet head in order to perform main scanning for selectively discharging and driving the inkjet head while moving the inkjet head with respect to the print object. In the inkjet head moving speed control device that moves at a constant speed and further decelerates, a target movement control means for controlling the acceleration movement of the inkjet head so that the movement speed becomes the set target speed, and a constant speed from the acceleration movement. Speed detecting means for detecting the reaching movement speed of the ink-jet head at the transition position to the movement, and table creating means for creating a speed control table that determines at least the constant speed movement and the deceleration movement speed based on the reaching movement speed; Based on the speed control table created by the table creation means, at least And table movement control means for controlling the constant speed movement and the deceleration movement of the ink jet head, characterized by comprising a.
[0014]
According to these configurations, since the speed control table for controlling the speed of the ink jet head is created based on the reaching moving speed of the ink jet head that is accelerated and moved toward the target speed, the speed control table according to the performance of each control motor is provided. Thus, the movement of the inkjet head can be controlled, and the inkjet head can be scanned efficiently (at high speed).
[0015]
In addition, detection of the reaching movement speed referred to in claims 1, 2, 6, and 7 is to directly detect the movement speed of the inkjet head at the transition position and to calculate from the movement speed at a predetermined position of the inkjet head that is accelerated. Meaning both by processing.
[0016]
In this case, the table creation process includes a constant speed table creation process for creating a constant speed movement table for constant speed movement, and a deceleration table creation process for creating a deceleration movement table for deceleration movement, and table control movement The process includes a constant speed movement control step for controlling the constant speed movement of the inkjet head based on the constant speed movement table, and a deceleration movement control step for controlling the deceleration movement of the inkjet head based on the deceleration movement table. The deceleration table creating step is preferably performed substantially in parallel with the constant velocity movement control of the inkjet head in the constant velocity movement control step.
[0017]
In this case, the table creation means includes a constant speed table creation means for creating a constant speed movement table for constant speed movement, and a deceleration table creation means for creating a deceleration movement table for deceleration movement. The control movement means has a constant speed movement control means for controlling the constant speed movement of the inkjet head based on the constant speed movement table, and a deceleration movement control means for controlling the deceleration movement of the inkjet head based on the deceleration movement table. The deceleration table creation means preferably creates the deceleration movement table substantially in parallel with the constant velocity movement control of the inkjet head by the constant velocity movement control means.
[0018]
According to these configurations, the creation of the deceleration movement table is performed in parallel (overlapping) with the constant speed movement of the inkjet head, so the deceleration movement table is created before the constant speed movement of the inkjet head is started. There is no need to do. That is, it is possible to reduce the amount of processing (speed control table creation processing time) that must be performed before the inkjet head is started to move at a constant speed, and the inkjet head can be moved efficiently.
[0019]
In these cases, the target speed is preferably determined based on the rated maximum output of the control motor. In these cases, the target speed is preferably determined based on the rated maximum output of the control motor.
[0020]
According to these configurations, by setting the target speed so that the rise time of the control motor is the shortest based on the rated maximum output of the control motor, the ultimate moving speed of the inkjet head can be set to the fastest state. . That is, since the speed control of the ink jet head can be performed in consideration of a state in which the performance of the control motor is utilized to the maximum, the ink jet head can be scanned at a higher speed.
[0021]
The ink jet printer of the present invention includes any one of the ink jet head speed control devices described above.
[0022]
According to this configuration, since the ink jet head speed control device is provided, the ink jet head can be scanned at high speed according to the performance of the control motor, and printing can be efficiently performed by increasing the printing speed. Can do.
[0023]
In this case, the transition position is preferably provided in front of the print start position in the main scanning direction of the inkjet head.
[0024]
According to this configuration, since the transition position is provided before the print start position, the inkjet head can be moved at a constant speed before printing is started. Therefore, stable printing can be performed without being affected by fluctuations in the acceleration of the inkjet head during printing.
[0025]
In these cases, the apparatus further includes a carriage on which the ink jet head is mounted, and an ink storage unit that supplies ink to the ink jet head. The ink storage unit is mounted on the carriage, and the control motor moves the ink jet head through the carriage. It is preferable to let it be.
[0026]
In this case, even if the amount of ink in the ink storage means changes with printing and the load on the control motor fluctuates, the speed control table is selected or created according to the load on the control motor. It is possible to print efficiently by scanning the inkjet head at high speed.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an inkjet printer according to a first embodiment of the present invention will be described with reference to the accompanying drawings. This inkjet printer is connected to a host computer such as a personal computer, and performs printing on roll paper P1 or sheet paper P2 that is a printing target based on print data transferred from the host computer.
[0028]
FIG. 1 is an external perspective view of the entire printer according to this embodiment, and FIG. 2 is an external perspective view of an ink jet printer with the rear cover opened and the front cover removed. As shown in both the drawings, the ink jet printer 1 is configured by an apparatus case 3 whose upper surface is covered with an opening / closing cover 2. The opening / closing cover 2 includes a front cover 4 and a rear cover 5, which can be opened and closed independently. A device frame 11 in which the internal device 6 is incorporated is fixed to the device case 3. A tray-like mounting frame 12 including a base frame 13 and a pair of side frames 14 is fixed to the front portion of the apparatus frame 11. An accommodation pocket 15 for accommodating the roll paper P1 is formed at the rear portion of the apparatus frame 11, and a cover frame 16 that supports the rear cover 5 so as to be freely opened and closed is fixed.
[0029]
The roll paper P1 stored in the storage pocket 15 is fed along the roll paper feed path R1 and discharged from the roll paper discharge port 21 formed in the rear cover 5. On the other hand, the cut sheet P2 is inserted from the cut sheet insertion opening 22 formed in the front portion of the apparatus case 3, and is fed along the cut sheet feed path R2, and then formed on the front cover 4. The paper is discharged from the cut sheet discharge port 23. Note that the roll paper feed path R1 and the cut sheet feed path R2 merge in the middle to form a merge feed path R3 extending substantially vertically from the bottom to the top and then branch again (see FIG. 3).
[0030]
The internal device 6 includes, as a basic configuration, an inkjet head 61 (described later), and includes a printing unit 31 for printing on a print object and a print object (roll paper P1 and cut paper P2). A feed means 32 for feeding along the feed path (R1, R2), an ink supply means 33 having an ink cartridge 111 for supplying ink to the inkjet head 61, and a cutting means for cutting the printed roll paper P1. 34, and control means 35 for controlling the whole of the inkjet printer 1 by controlling each of these means in relation to each other. The ink jet head control device described in the claims comprises a control means 35 and a speed detection sensor 58 described later.
[0031]
As shown in FIG. 2, the printing unit 31 is supported by the mounting frame 12 and is supported by the head moving mechanism 41 and the head moving mechanism 41 for moving the inkjet head 61 that discharges ink in the X-axis direction. And a head unit 42 on which the inkjet head 61 is mounted.
[0032]
As shown in the figure, the head moving mechanism 41 is connected to the carriage motor 51 and a carriage motor 51 (control motor) for moving the head unit 42 (inkjet head 61) in the X-axis direction, that is, the main scanning direction. The timing belt 54 spanned between the right driving pulley 52 and the left driven pulley (not shown) and the head unit 42 are supported slidably in the X-axis direction, and the movement of the head unit 42 is guided. And a guide member 55.
[0033]
The carriage motor 51 is composed of a DC servo motor that can rotate forward and backward, and a rotation speed sensor 58 that detects the number of rotations of the carriage motor 51 is fixed to the end of the output shaft. The rotation speed sensor 58 is composed of a rotary encoder including a slit disk and a photo interrupter facing the slit disk. Although details will be described later, the rotational speed of the carriage motor 51 and the moving speed of the head unit 42 are closely related. By controlling the rotational speed of the carriage motor 51 based on the rotational speed sensor 58, Speed control can be performed.
[0034]
The driving pulley 52 and the driven pulley are fixed to the mounting frame 12 so that the timing belt 54 is stretched in parallel with the main scanning direction. The guide member 55 is stretched over the side frame 14 in parallel with the main scanning direction. The guide member 55 includes a guide rod 56 and a guide plate 57, and a carriage 62 (described later) of the head unit 42 is slidably supported by these members. The movable range of the head unit 42, that is, the head moving area M, is determined in advance, and the head moving mechanism 41 reciprocates the head unit 42 within the range of the head moving area M.
[0035]
The head unit 42 includes an inkjet head 61 and a carriage 62 on which the inkjet head 61 is mounted. The ink jet head 61 faces the merging / feeding path R3 and ejects ink droplets onto a print object that is fed through the merging / feeding path R3. The ink that receives ink supply from the ink cartridge 111 of the ink supply unit 33 An introduction section (not shown) and a head main body 64 for discharging the supplied ink are provided. The head main body 64 includes a nozzle plate 65 in which a large number of discharge nozzles (not shown) are formed and a cavity 67 in which a piezoelectric element is incorporated. In the ink jet head 61, ink is discharged from the discharge nozzles by the pumping action of the cavities 67. Drops are ejected.
[0036]
As shown in FIGS. 2 and 3, the carriage 62 is supported by the guide member 55 of the head moving mechanism 41, while the nozzle plate 65 of the ink jet head 61 is parallel to the merge feed path R <b> 3 that extends vertically. In other words, the ink jet head 61 is held by projecting the head body 64 to the merging feed path R3 so that the nozzle plate 65 is vertical. The base of the carriage 62 is fixed to a part of the timing belt 54. When the carriage motor 51 rotates forward and backward, the carriage 62 moves the head via the timing belt 54 while maintaining the support posture of the inkjet head 61. It reciprocates in the region M (in the main scanning direction).
[0037]
The placement frame 12 is provided with an X-axis linear encoder 68 so that the movement position of the carriage moving in the head movement area M in the main scanning direction can be accurately grasped. Although not shown, the X-axis linear encoder 68 is composed of a linear scale extending in the main scanning direction and a photosensor mounted on the carriage 62. A large number of photosensors provided on the linear scale are provided by the photosensor. By sequentially detecting (counting up) the detection lines, the position of the moving carriage 62 can be detected. In addition, a guide plate 69 is disposed in the merging / feeding path R3 so as to be close to and opposed to the nozzle plate 65 of the inkjet head 61 and extends in the main scanning direction. The guide plate 69 guides the printing object so that the paper gap of the printing object facing the head 61 is kept constant, whereby appropriate printing is performed on the printing object (see FIG. 3).
[0038]
The feeding means 32 feeds the print object in the sub-scanning direction (Y-axis direction) along a predetermined feeding path. The feeding means 32 feeds the roll paper P1 accommodated in the accommodation pocket 15 and delivers the roll paper. A roll paper feed mechanism 71 that feeds P1 along the roll paper feed path R1 to the roll paper discharge port 21, and a cut sheet P2 inserted from the cut sheet insertion slot 22 A cut sheet feed mechanism 72 that feeds to the sheet discharge port 23, a roll motor feed mechanism 71, a drive motor 73 that serves as a drive source for the cut sheet feed mechanism 72, and the power of the drive motor 73 to the roll paper feed mechanism 71 and A power transmission mechanism (not shown) that selectively transmits to the cut sheet feeding mechanism 72 at a reduced speed is provided (see FIG. 3).
[0039]
The roll paper feed mechanism 71 is arranged along the roll paper feed path R1, is arranged on the upstream side of the roll paper feed path R1, and feeds the roll paper P1 accommodated in the accommodation pocket 15. Unit 81 and a roll that is arranged downstream of the roll paper feed path R1 and that feeds the roll paper P1 fed out by the roll paper feed section 81 to the roll paper discharge port 21 along the roll paper feed path R1. A paper discharge unit 82. The roll paper feed unit 81 has a paper feed roller 83 for feeding the roll paper P1. The paper feed roller 83 is composed of a grip roller that faces the roll paper P 1 and sandwiches the roll paper P 1, and a paper feed drive roller 84 connected to the drive motor 73 and a paper feed driven roller biased by the paper feed drive roller 84. 85. The roll paper discharge unit 82 includes a discharge roller 86 that discharges the fed roll paper P1. Similarly to the paper feed roller 83, the paper discharge roller 86 is also constituted by a grip roller, a paper discharge drive roller 87 connected to the drive motor 73, a paper discharge driven roller 88 biased by the paper discharge drive roller 87, have.
[0040]
The cut sheet feed mechanism 72 is disposed along the cut sheet feed path R2, and includes a cut sheet feed roller 91 for feeding the inserted cut sheet P2 along the cut sheet feed path R2. Have. Similarly to the paper feed roller 83, the cut paper feed roller 91 is also constituted by a grip roller, and a drive roller 92 connected to the drive motor 73 and a driven roller urged to press the drive roller 92. 93. The drive motor 73 is composed of a DC servo motor capable of rotating in the forward and reverse directions, and a feed amount detection sensor 101 (slit disk and facing this) that detects the number of rotations of the drive motor 73 at the shaft end of its output shaft. A rotary encoder comprising a photo interrupter is fixed. The feed amount of the print object is defined by the rotation amount of the drive motor 73. By controlling the drive motor 73 based on the feed amount detection sensor 101, the feed amount of the print object can be controlled. ing.
[0041]
Although not shown, the power transmission mechanism transmits power to the roll paper feed mechanism 71 and the cut paper feed mechanism 72 via a gear train that decelerates and transmits the power of the drive motor 73. In addition, a clutch mechanism is incorporated in the gear train. For example, power is transmitted to the roll paper feed mechanism 71 when the drive motor 73 is rotating forward, and to the cut paper feed mechanism 72 when the drive motor 73 is reverse. As described above, the power is selectively transmitted to the roll paper feed mechanism 71 or the cut paper feed mechanism 72 by using the forward / reverse rotation of the drive motor 73.
[0042]
The ink supply means 33 is mounted on the mounting frame 12 and connects the ink cartridge 111 for storing ink, the ink cartridge 111 and the inkjet head 61, and supplies ink from the ink cartridge 111 to the inkjet head 61. And a liquid supply tube (not shown). The ink jet printer 1 of the present embodiment is a color printer. The ink jet printer 1 is supplied with an ink cartridge 111a filled with black (B) ink, and yellow (Y), magenta (M), and cyan (C) ink. And a filled ink cartridge 111b. In this embodiment, the ink cartridge 111 is fixed to the mounting frame 12, but the ink cartridge 111 may be mounted on the carriage 62 and moved together with the head unit 42. Is possible.
[0043]
The cutting means 34 includes a roll paper cutter (not shown) provided near the roll paper discharge port 21 and a cutter motor 122 for causing the roll paper cutter to perform a cutting operation. The control means 35 is connected to each means of the inkjet printer 1 and controls the entire inkjet printer 1 in an integrated manner.
[0044]
Next, the main control system of the inkjet printer 1 will be described. As shown in FIG. 4, the inkjet printer 1 has a printer interface 202 and inputs print data (image data and print control data) and various commands transmitted from the host computer, and various data in the inkjet printer 1. A data input / output unit 201 for outputting to a host computer, a printing unit 203 for printing on a printing object, a cutting unit 204 for cutting the printed roll paper P1, and a detection unit 205 for performing various detections. And a drive unit 206 that has various drivers and drives each unit, and a control unit 207 that is connected to these units and controls the entire inkjet printer 1.
[0045]
The printing unit 203 includes a printing unit 31 and a sending unit 32. A series of operations of the printing unit 203 during printing will be described. When the printing process is started, first, main scanning is performed. In the main scanning, the inkjet head 61 is selectively ejected together with the carriage motor 51, and one line is printed on the print area of the print target. That is, in the main scanning, the inkjet head 61 is driven to discharge based on the detection signal of the X-axis linear encoder 68 while moving the carriage 62 in the main scanning direction (forward movement), so that a predetermined printing area is obtained. 1 line is printed. After the printing of one line is completed, the drive of the carriage motor 51 is stopped and one main scan is completed. The one-line printing here means printing performed by one main scanning.
[0046]
On the other hand, when printing of one line is completed, sub-scanning is performed next. In the sub-scanning, the drive motor 73 is driven, and the print target is fed by a predetermined amount (for example, for one line) based on the feed amount detection sensor 101 described above. That is, after the printing of one line is completed, the printing object is sent to the printing start position of the next line. When the sub-scanning is completed, the main scanning is performed again, the carriage motor 51 is re-driven, and the inkjet head 61 is selectively ejected. That is, while the carriage 62 is moved backward, the inkjet head 61 is driven to discharge based on the X-axis linear encoder 68, and one line is printed. As described above, by repeating the main scanning and the sub scanning, printing is performed line by line on the print target.
[0047]
If the printing of one line is completed, the sub-scanning can be started even if the main scanning is not completed. In the present embodiment, the drive motor 73 is substantially simultaneously with the completion of the printing of one line. Is driven, and the carriage motor 51 is re-driven substantially simultaneously with the completion of the feeding operation of the printing object by the drive motor 73. In this way, the printing time can be shortened by overlapping the main scanning and performing the sub scanning.
[0048]
The cutting unit 204 includes a cutting unit 34. When printing on the roll paper P1 is completed, the cutter motor 122 is driven to cut the roll paper P1. The detection unit 205 includes various sensors for controlling the inkjet printer 1 such as the speed detection sensor 58, the X-axis linear encoder 68, and the feed amount detection sensor 101. The drive unit 206 includes a head driver 211 for driving the inkjet head, a motor driver 212 for driving various motors, and the like. The motor driver 212 includes a carriage motor driver 213 for driving the carriage motor 51, a drive motor driver 214 for driving the drive motor 73, a cutting driver 215 for driving the cutter motor 122, and the like. ing.
[0049]
The control unit 207 includes a CPU 221, a ROM 222, a RAM 223, and a peripheral control circuit (P-CON) 224, which are connected to each other via an internal bus 225. The ROM 222 has a control data area for storing control data including a color conversion table and a character modification table in addition to a control program area for storing a control program processed by the CPU 221. The RAM 223 includes an image data area for storing image data input from the outside, a print image data area for storing image data for printing, a color conversion buffer area corresponding to each color, and various register groups. Used as work area for.
[0050]
In the P-CON 224, a logic circuit for supplementing the function of the CPU 221 and handling an interface signal with a peripheral circuit is configured by a gate array or a custom LSI. That is, the P-CON 224 captures the print data and various detection signals from each part of the host computer and the inkjet printer 1 as they are or processes them into the internal bus 225 and links to the internal bus 225 from the CPU 221 and the like in conjunction with the CPU 221. The output data and control signals are output to each part of the inkjet printer 1. Further, the P-CON 224 incorporates a timer for performing time control.
[0051]
The CPU 221 inputs various detection signals, various commands, various data, etc. via the P-CON 224 according to the control program in the ROM 222, processes various data, etc. in the RAM 223, and then drives the drive unit 206 via the P-CON 224. Output a control signal. In this way, each part of the inkjet printer 1 is controlled by the control unit 207 so that the entire inkjet printer 1 is controlled.
[0052]
Based on the above, the speed control method of the head unit 42 during main scanning will be described. Since the acceleration fluctuation of the head unit 42 caused by the movement of the head unit 42 adversely affects the ejection result of the inkjet head 61, that is, the print quality, the control unit 207 (control unit 35) causes the head unit 42 to move during main scanning. Speed control is performed.
[0053]
FIG. 5 is a diagram showing the relationship between the moving speed and the moving position of the head unit 42 that moves in the head moving area M. As shown in the figure, the head unit 42 accelerates from a movement start position P1 to a predetermined constant speed movement start position P3, then moves at a constant speed to a predetermined deceleration movement start position P4, and starts a deceleration movement start position P4. The vehicle is decelerated from, and stops at a predetermined movement end position P2. In order to stabilize the print quality, the ejection drive of the inkjet head 61 is performed while the head unit 42 is moving at a constant speed. In this case, it is possible to make the constant velocity movement start position P3 coincide with the printing start position, and the head unit 42 starts the ejection drive of the inkjet head 61 at the same time as the head unit 42 reaches the constant velocity movement start position P3. Since the acceleration (movement speed) of the head unit 42 becomes unstable when moving from the acceleration movement to the constant speed movement, as shown in FIG. 5, after the head unit 42 reaches the constant speed movement start position P3, as shown in FIG. A configuration facing the printing region D is preferable.
[0054]
As described above, the head unit 42 is moved by driving the carriage motor 51, and the control unit 207 controls the rotation driving of the carriage motor 51, so that the head unit 42 is moved at a predetermined position. The moving speed of the head unit 42 is controlled so as to accelerate and decelerate. In the control data area in the ROM 222, a speed control table T in which the moving speed of the head unit 42 is determined in advance corresponding to the moving position of the head unit 42 is stored in advance. Based on T.
[0055]
Referring to FIG. 6, first, the movement speed of the head unit 42 is calculated from the detection signal of the speed detection sensor 58 (by the speed conversion circuit of the P-CON 224), and the target movement speed of the speed control table T is calculated. The speed deviation Vd is obtained by comparison. Next, an operation amount Q (applied voltage to the carriage motor 51) to the carriage motor 51 is calculated from the obtained speed deviation Vd by an operation amount operation circuit (for example, a PID operation circuit or a PI operation circuit) of the P-CON 224. . Then, the voltage of the calculated operation amount Q is applied to the carriage motor 51 via the carriage motor driver 213 described above, whereby the rotational drive of the carriage motor 51 is controlled and the moving speed of the head unit 42 is controlled ( Feedback control).
[0056]
By the way, the printing speed with respect to the printing object depends on the moving speed of the head unit 42. Since the printing time can be shortened by increasing the moving speed of the head unit 42, the head unit 42 is moved faster. It is preferable.
That is, it is preferable to accelerate the head unit 42 so that the moving speed of the head unit 42 that reaches the constant velocity movement start position P3 becomes higher. On the other hand, since the performance of the motor applied to the carriage motor 51 varies, the moving speed at which the head unit 42 can reach the predetermined constant-velocity movement start position P3 is different for each inkjet printer 1.
[0057]
Therefore, a plurality (three) of speed control tables T1, T2, and T3 having different moving speeds at the constant speed movement start position P3 are stored in the ROM 222 of the present embodiment, and according to the performance of the carriage motor 51. , (One) speed control table T can be selected.
[0058]
FIG. 7A is a view showing three speed control tables T1, T2, and T3 stored in the ROM 222. FIG. As shown in the figure, the head movement area M is composed of a target movement area Mt and a control movement area Mc. In each speed control table T, the movement speed of the head unit 42 in the control movement area Mc is determined. Yes. (In the target movement area Mt, the speed control of the head unit 42 based on the speed control table T is not performed.) The target movement area Mt is an area for estimating the performance of the carriage motor 51, and the target movement area Mt. The speed control table T is selected according to the performance of the carriage motor 51 estimated in step (b).
[0059]
The target arrival speed Vt (target speed) of the head unit 42 is set in advance at the constant speed movement start position P3. In the target movement area Mt, the arrival movement speed Vr of the head unit 42 at the constant speed movement start position P3 is set. The head unit 42 is accelerated and moved so as to reach the target arrival speed Vt. In order to increase the reaching movement speed Vr, it is preferable that the target arrival speed Vt is set higher. Further, based on the rated maximum output of the carriage motor 51, the target arrival speed Vt is set so that the capability of the carriage motor 51 is fully opened, that is, the rising time of the carriage motor 51 is the shortest. More preferably. According to this, since the speed control table T can be selected in consideration of the state in which the performance of the carriage motor 51 is utilized to the maximum, it is possible to efficiently shorten the printing time.
[0060]
In the present embodiment, the boundary between the target movement area Mt and the control movement area Mc is set to be located on the near side of the constant speed movement start position P3. However, it coincides with the constant speed movement start position P3. It may be set.
[0061]
A series of operations for controlling the speed of the head unit 42 during main scanning will be described. As shown in FIG. 7B, the control unit 207 first drives the carriage motor 51 to accelerate the head unit 42 toward the predetermined target arrival speed Vt, and causes the head unit 42 to move to the target movement region Mt. Is moved (target movement process). When it is detected by the above-described X-axis linear encoder 68 that the head unit 42 that accelerates the movement has reached the predetermined detection position P5 in the target movement region Mt, the control unit 207 causes the speed detection sensor 58 described above. From the (speed detecting means), the moving speed of the head unit 42 at the detection position P5, that is, the reference speed Vs is measured (speed detecting step).
[0062]
The detection position P5 can be set at an arbitrary position according to the actual condition within the target movement area Mt. For example, the detection position P5 is positioned at the boundary between the target movement area Mt and the control movement area Mc. Also good. Further, the movement of the head unit 42 within the target movement area Mt may be given a target arrival speed Vt as a fixed value, and the head unit 42 may be accelerated and moved at this target, or the target arrival at the constant speed movement start position P3. A target table in which the moving speed and moving position of the head unit 42 are determined so as to be the speed Vt may be given, and the head unit 42 may be moved according to the target table.
[0063]
Next, the control unit 207 estimates the reaching movement speed of the head unit 42 from the reference speed Vs, and selects one speed control table T from the three speed control tables T based on the estimated reaching movement speed ( Table selection process). In other words, the control unit 207 selects the speed control table T according to the performance of the carriage motor 51, thereby reliably performing the speed control of the head unit 42 in a state in which the control unit 207 substantially matches the speed control table T. Therefore, appropriate printing is performed on the printing object.
[0064]
More specifically, with reference to FIG. 7A, each speed control table T is set corresponding to the reached travel speed Vr. When the estimated reach travel speed Vr is equal to or higher than V1, the speed is constant. The speed control table T1 in which the moving speed of the head unit 42 is set to be the fastest at the movement start position P3 is selected. If the estimated reaching movement speed Vr is not less than V2 and less than V1, the speed control table T2 is selected and estimated. When the reached movement speed Vr is less than V2, the speed control table T3 in which the movement speed of the head unit 42 at the constant speed movement start position P3 is set to the slowest is selected. However, it is assumed that V1> V2.
[0065]
The ultimate moving speed Vr is obtained by an arithmetic expression obtained experimentally. Then, the association between each speed control table T and the ultimate movement speed Vr is set based on experiments and the like in consideration of the characteristics of the carriage motor 51 and the like. When the detection position P5 substantially coincides with the constant speed movement start position P3, the reference speed Vs is regarded as the reaching movement speed Vr, and the speed control table T is directly selected from the reference speed Vs.
[0066]
When the speed control table T is selected, in order to move the head unit 42 according to the selected speed control table T, the control unit 207 performs drive control of the carriage motor 51 and moves the control movement area to the head unit 42 (table movement control). Process). These series of operations are performed according to a control program stored in the ROM 222. As a matter of course, the number of speed control tables T used for speed control of the head unit 42 can be arbitrarily set.
[0067]
As described above, in the present embodiment, a plurality of speed control tables are provided in order to cope with variations in performance of the carriage motor 51, and (one) speed control table is selected in accordance with the performance of the carriage motor 51. Therefore, it is possible to shorten the printing time and perform printing efficiently.
[0068]
In this embodiment, since the speed control table T is selected while actually driving the carriage motor 51 (moving the head unit 42), the load on the carriage motor 51 varies. Is also effective. For example, when the load applied to the carriage motor 51 varies during printing, such as when the ink cartridge 111 is mounted on the carriage 62, the control table is set according to the performance of the carriage motor 51 and the load applied to the carriage motor 51. Can be selected. Thereby, when the load applied to the carriage motor 51 is small, the head unit 42 can be moved at a constant speed at a higher speed than when the load is large, and printing can be performed efficiently. In such a case, the frequency of selecting the speed control table T may be set according to the actual situation. For example, it may be performed for each main scan or for each printing process, or may be performed at predetermined time intervals.
[0069]
In addition, by applying the present invention to the drive motor 73 that sends the print object, it is possible to send the print object appropriately and efficiently according to the performance of the drive motor 73 and the load applied to the drive motor 73. is there.
[0070]
Next, a second embodiment will be described. The ink jet printer 1 of the present embodiment is different in the speed control method of the head unit 42 performed by the control unit 207, but has a configuration substantially similar to that of the first embodiment, so here the first embodiment is different from the first embodiment. Only the differences will be described.
[0071]
In the first embodiment, a plurality of speed control tables T are stored in advance in the ROM 222, and one speed control table T is selected according to the performance of the carriage motor 51. However, in the present embodiment, A control program for creating the speed control table T is stored in the ROM 222 of the inkjet printer 1, and the speed control table T is created according to the performance of the carriage motor 51.
[0072]
In the present embodiment, first, the head unit 42 is moved toward the target arrival speed Vt, and the reference speed Vs of the head unit 42 is detected at the detection position P5. Then, after the arrival movement speed Vr of the head unit 42 is estimated from the reference speed Vs (the same as in the first embodiment so far), the speed control table T is created, and the control movement is performed according to the created speed control table T. The head unit 42 is moved in the area Mc. The speed control table T controls an acceleration control table Ta for controlling the head unit 42 moving at an accelerated speed, a constant speed control table Tu for controlling the head unit 42 moving at a constant speed, and a head unit 42 moving at a reduced speed. And a deceleration control table Ts for performing these operations, which are created in order.
[0073]
Referring to FIG. 8, a series of operations when creating the speed control table T will be described. After the arrival movement speed Vr is estimated, the arrival movement speed Vr estimated at the constant speed movement start position P3 is obtained. Based on a predetermined arithmetic expression, an acceleration control table Ta from the detection position P5 to the constant speed movement start position P3 is created (table creation process). When the creation of the acceleration control table Ta is completed, a constant speed control table Tu that is determined to move the head unit 42 at the estimated reaching movement speed Vr from the constant speed movement start position P3 to the deceleration movement start position P4 is created ( (Constant-velocity movement table creation step) Subsequently, a deceleration control table Ts is created based on a predetermined arithmetic expression (deceleration movement table creation step).
[0074]
On the other hand, the movement of the head unit 42 is performed in parallel with the creation of the speed control table T. The controller 207 accelerates the head unit 42 according to the created acceleration control table Ta so as to follow the creation of the acceleration control table Ta, and then the head unit based on the created constant speed control table Tu and deceleration control table Ts. 42 is moved. The deceleration control table Ts only needs to be created before the head unit 42 reaches the deceleration start position P4, and the deceleration control table Ts is created so as to overlap with the constant speed movement of the head unit 42 (note that If the creation of the constant velocity control table Tu is completed during the acceleration movement, the deceleration control table Ts is created in parallel with the acceleration movement).
[0075]
In this manner, a part of the speed control table T is created prior to the movement of the head unit 42, and the remaining part is created in parallel with the movement of the head unit 42, whereby the movement of the head unit 42 is started. The time required for creating the speed control table T can be shortened. Further, since the speed control table T is created prior to the movement of the head unit 42, after the head unit 42 starts moving, the head unit 42 is based on the speed control table T without stopping the head unit 42. Can be moved smoothly.
[0076]
In this embodiment as well, in order to make the best use of the performance of the carriage motor 51 and reduce the printing time, the carriage motor 51 is fully opened based on the rated maximum output of the carriage motor 51. It is more preferable to set the target arrival speed Vt. When the detection position P5 substantially coincides with the constant speed movement start position P3, the reference speed Vs is regarded as the reaching movement speed Vr, and the creation of the acceleration control table Ta is omitted. Only the speed control table Tu and the deceleration control table Ts are created.
[0077]
As described above, in the inkjet printer 1 according to the second embodiment, the speed control table T is created in accordance with the performance of the carriage motor 51. Therefore, efficient printing is performed by making the best use of the performance of the carriage motor 51. In addition, the moving speed of the head unit 42 can be reliably controlled according to the speed control table, and appropriate printing can be performed.
[0078]
【The invention's effect】
As described above, in the moving speed control method and moving speed control apparatus for an inkjet head according to the present invention, one speed control table corresponding to the characteristics (performance) of the carriage motor is selected from a plurality of speed control tables. The moving speed control of the inkjet head is performed based on the selected one speed control table. That is, it is not necessary to control the driving of the carriage motor based on the uniformly determined speed control table, and a speed control table with a higher output state can be selected according to the characteristics of each carriage motor. It is possible to shorten the scanning time.
[0079]
The ink jet head moving speed control method and the moving speed control apparatus of the present invention create a speed control table in accordance with the characteristics of each carriage motor, and control the ink jet head moving speed based on the speed control table. Therefore, the ink jet head can be scanned at a higher speed by creating a speed control table so that the carriage motor is in a higher output state in accordance with the characteristics of each carriage motor.
[0080]
In addition, since the present invention includes the above moving speed control device, the scanning time of the inkjet head can be shortened and the printing time can be reduced by scanning the inkjet head at high speed. .
[Brief description of the drawings]
FIG. 1 is an external perspective view of an ink jet printer to which the present invention is applied.
FIG. 2 is an external perspective view of the ink jet printer with the rear cover opened and the front cover removed.
FIG. 3 is a cross-sectional view of an ink jet printer.
FIG. 4 is a block diagram illustrating a control system of the ink jet printer.
FIG. 5 is a diagram illustrating a relationship between a moving speed and a moving position of a head unit that moves in a head moving region, and a relationship between a carriage speed and a printing region.
FIG. 6 is a block diagram for explaining a series of flows in the movement speed control of the head unit.
FIG. 7 is an explanatory diagram for explaining the movement speed control of the head unit in the first embodiment, and FIG. 7A shows three speed control tables stored in the ROM of the first embodiment. FIG. 8B is a diagram showing the relationship between the speed of the head unit and the movement position when the target movement area is accelerated and moved to the head unit so as to reach the target arrival speed at the constant velocity movement start position. It is.
FIG. 8 is an explanatory diagram for explaining the movement speed control of the head unit in the second embodiment, where the solid line portion indicates the movement speed of the head unit in the target movement region, and the broken line portion indicates the detection position. The created speed control table is shown based on the reached moving speed estimated from the moving speed of the head unit.
[Explanation of symbols]
1 Inkjet printer 35 Control means
51 Carriage motor 58 Speed detection sensor
61 Inkjet head 62 Carriage
111 Ink cartridge 207 Control unit
P3 Constant velocity start position
T Speed control table

Claims (11)

In order to perform main scanning for selectively discharging and driving the inkjet head while moving the inkjet head with respect to the printing object, the inkjet head is accelerated and moved at a constant speed using a control motor. Further, in the moving speed control method of the ink jet head that is further decelerated, a target movement control step for controlling the acceleration movement of the ink jet head so that the moving speed becomes a set target speed;
A speed detection step of detecting an arrival movement speed of the inkjet head at a transition position from the acceleration movement to the constant speed movement;
A table selection step of selecting one of the speed control tables from a plurality of speed control tables in which the movement speeds of at least the constant speed movement and the deceleration movement are determined in advance based on the attainment movement speed;
An inkjet head comprising: a table movement control step for controlling at least the constant velocity movement and the deceleration movement of the inkjet head based on the one speed control table selected in the table selection step. Movement speed control method. In order to perform main scanning for selectively discharging and driving the inkjet head while moving the inkjet head with respect to the printing object, the inkjet head is accelerated and moved at a constant speed using a control motor. Further, in the moving speed control method of the ink jet head that is further decelerated, a target movement control step for controlling the acceleration movement of the ink jet head so that the moving speed becomes a set target speed;
A speed detection step of detecting an arrival movement speed of the inkjet head at a transition position from the acceleration movement to the constant speed movement;
A table creation step of creating a speed control table that defines a moving speed of at least the constant speed movement and the decelerated movement based on the attainment moving speed;
And a table movement control step for controlling at least the constant velocity movement and the deceleration movement of the inkjet head based on the velocity control table created in the table creation step. Control method. The table creation step is a constant velocity table creation step of creating the constant velocity movement table for the constant velocity movement,
A deceleration table creation step of creating a deceleration movement table for the deceleration movement,
The table control movement step includes a constant velocity movement control step for controlling the constant velocity movement of the inkjet head based on the constant velocity movement table;
A deceleration movement control step for controlling the deceleration movement of the inkjet head based on the deceleration movement table,
The method according to claim 2, wherein the deceleration table creation step is performed substantially in parallel with the constant velocity movement control of the inkjet head in the constant velocity movement control step. 4. The method for controlling the moving speed of an ink jet head according to claim 1, wherein the target speed is determined based on a rated maximum output of the control motor. In order to perform main scanning in which the inkjet head is selectively driven to discharge while moving the inkjet head relative to the print object, the inkjet head is accelerated and moved at a constant speed using a control motor. Further, in the moving speed control device for the ink jet head that is further decelerated, target moving control means for controlling the acceleration movement of the ink jet head so that the moving speed becomes a set target speed;
Speed detecting means for detecting a reaching moving speed of the inkjet head at a transition position from the acceleration movement to the constant speed movement;
Table selecting means for selecting one speed control table from a plurality of speed control tables in which at least the constant speed movement and the decelerating movement are determined based on the ultimate movement speed;
An inkjet head comprising: table movement control means for controlling at least the constant speed movement and the deceleration movement of the inkjet head based on the one speed control table selected by the table selection means. Moving speed control device. In order to perform main scanning in which the inkjet head is selectively driven to discharge while moving the inkjet head relative to the print object, the inkjet head is accelerated and moved at a constant speed using a control motor. Further, in the moving speed control device for the ink jet head that is further decelerated, target moving control means for controlling the acceleration movement of the ink jet head so that the moving speed becomes a set target speed;
Speed detecting means for detecting a reaching moving speed of the inkjet head at a transition position from the acceleration movement to the constant speed movement;
A table creating means for creating a speed control table that defines at least the moving speeds of the constant speed movement and the decelerating movement based on the reaching movement speed;
Table moving control means for controlling at least the constant speed movement and the decelerating movement of the inkjet head based on the speed control table created by the table creating means, Control device. The table creation means includes a constant speed table creation means for creating the constant speed movement table for the constant speed movement,
A deceleration table creating means for creating a deceleration movement table for the deceleration movement,
The table control moving means is a constant speed movement control means for controlling the constant speed movement of the inkjet head based on the constant speed movement table;
Decelerating movement control means for controlling the decelerating movement of the inkjet head based on the decelerating movement table,
7. The moving speed of the inkjet head according to claim 6, wherein the deceleration table creating means creates the deceleration moving table substantially in parallel with the constant velocity movement control of the inkjet head by the constant velocity movement control means. Control device. 8. The moving speed control device for an inkjet head according to claim 5, wherein the target speed is determined based on a rated maximum output of the control motor. An ink jet printer comprising the ink jet head moving speed control device according to claim 5. The inkjet printer according to claim 9, wherein the transition position is provided in front of a print start position in a main scanning direction of the inkjet head. A carriage carrying the inkjet head;
Ink storage means for supplying ink to the inkjet head,
The ink storage means is mounted on the carriage,
The ink jet printer according to claim 9 or 10, wherein the control motor moves the ink jet head via the carriage.

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