JP2009196177A - Fluid discharging device and bidirectional recording method for fluid discharging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid discharging device capable of reducing deviation of a recording position in a scanning direction of a discharging means to a target due to a difference in moving speed of the discharging means, and a bidirectional recording method for the fluid discharging device. <P>SOLUTION: A printing start position PS and a printing finish position PE sent from an image forming processing part are set (S10), a discharging start position adjusted value αk and a Bi-D adjusted value βk in accordance with carriage speed Vk are read in (S20). An ink discharging start position ISa when printing in going is calculated by an expression ISa=PS+αk (S30 and S40). An ink discharging start position ISb when printing in returning is calculated by an expression ISb=PS+βk (S30 and S50). The ink discharging start position is set in a head control part (S60), and a carriage start-up position is calculated and set in a carriage control part (S70). Then, printing operation is performed (S80). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluid ejection apparatus in which ejection means reciprocates in a scanning direction to perform scanning bidirectional recording on a target, and a bidirectional recording method in the fluid ejection apparatus.

  2. Description of the Related Art Conventionally, in a serial type ink jet printer that is a fluid ejecting apparatus of this type, printing is performed by ejecting ink droplets from a nozzle of a recording head to a target such as paper during the movement of the carriage. . At this time, for the purpose of speeding up printing, a bidirectional printing method in which ink droplets are ejected from the nozzles on both the forward and return passes of the recording head, and ink droplets are ejected from the recording head only on one of the forward and return passes. And a one-way printing method for recording.

  In the case of a serial printer, since ink droplets are ejected from the nozzles while the recording head is moving, the carriage velocity component (that is, the recording head velocity component) causes the dot to be shifted in the carriage traveling direction from the ink droplet ejection start position. Is formed. In the case of bi-directional printing, it is necessary to match the recording position of the forward path of the recording head with the recording position of the return path, so that the ink ejection start position of the forward path is set to match the recording position of the return path with respect to the recording position of the forward path. Is adjusted.

For example, in the patent document, a reference correction value for correcting a shift in the recording position in the main scanning direction in the forward path and the backward path is set for a specific reference head, and at least the main scanning in the forward path and the backward path is performed using the reference correction value. A bidirectional printing apparatus is disclosed that determines an adjustment value for reducing the deviation of the recording position in the direction. In this bidirectional printing apparatus, the recording position in the main scanning direction in the forward path and the backward path is adjusted using the determined adjustment value, so that the recording position in the main scanning direction in the forward path and the backward path is adjusted. It was the composition which adjusts. Although it is described that the positional deviation should be corrected by adjusting at least one of the forward path and the return path (for example, paragraph [00125]), specific details of the correction are disclosed or suggested. Absent.
Japanese Unexamined Patent Publication No. 2004-291651 (for example, first embodiment, paragraph [0068], FIG. 17 and the like)

  In Patent Document 1 (first embodiment, etc.), the ink discharge position with respect to the print position of the forward path is an adjustment value for determining the print positions of the forward path and the return path to coincide with each other. The predetermined position was set regardless of the carriage speed. In this case, since the ejection is started from a certain position regardless of the carriage speed, the image recording position (image printing position) on the paper is slightly (0.1 to 0) in the forward traveling direction due to the difference in the carriage speed. .5 mm). The print position deviation in the forward traveling direction with respect to the paper increases as the carriage speed increases. For this reason, the images printed on the paper during high-speed printing and during low-speed printing are printed with a slight shift in the paper width direction. In recent years, the carriage speed has been increased due to the demand for higher printing speed. However, this printing deviation becomes more noticeable as the carriage speed increases, and cannot be ignored.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the displacement of the recording position in the scanning direction of the ejection unit relative to the target due to the difference in the moving speed of the ejection unit. Another object of the present invention is to provide a fluid ejecting apparatus and a bidirectional recording method in the fluid ejecting apparatus.

  The present invention provides an ejection unit that ejects a fluid to a target, a moving unit that reciprocates the ejection unit in a scanning direction, and controls the ejection unit and the movement unit to perform bidirectional recording and the ejection unit. And a control means for controlling at a designated one of the plurality of movement speeds, the fluid discharge apparatus comprising: a displacement of the recording position of the forward path of the discharge means relative to the target between the plurality of movement speeds. A first adjusting unit that adjusts a fluid discharge start position in the forward path of the ejection unit relative to a recording start position of the forward path determined from given ejection instruction data in accordance with a designated moving speed of the discharge unit in order to decrease In order to reduce the deviation of the recording position of the return path from the recording position of the outbound path in which the fluid discharge start position is adjusted by the first adjusting means, A gist that a second adjusting means for adjusting in accordance with the body discharge starting position of the moving speed that is the specified.

  According to this invention, the control means controls the ejection means and the movement means, and bidirectional printing is performed by reciprocating the ejection means in the scanning direction at a designated movement speed among a plurality of movement speeds of the ejection means. Done. In this bidirectional recording, the first adjusting means designates the fluid discharge start position in the forward path of the ejection means at that time so as to reduce the deviation of the recording position of the forward path of the ejection means with respect to the target between a plurality of moving speeds. It is adjusted according to the moving speed. In addition, the second adjustment means designates the fluid discharge start position in the return path at that time in order to reduce the deviation of the recording position in the return path from the recording position of the forward path in which the fluid discharge start position is adjusted by the first adjustment means. It is adjusted according to the moving speed. As a result, even if the moving speed of the ejection unit is different, it is possible to suppress the deviation of the recording position in the scanning direction with respect to the target. Therefore, it is possible to avoid an increase in the recording position shift with respect to the target due to an increase in the moving speed of the discharge means.

(First embodiment)
Hereinafter, a first embodiment in which the present invention is applied to an ink jet printer will be described with reference to FIGS. FIG. 2 is a perspective view of the ink jet recording apparatus with the outer case removed. As shown in FIG. 2, an ink jet recording apparatus (hereinafter referred to as a printer 11) as a fluid ejecting apparatus is mainly provided along a guide shaft 13 installed in a substantially square box-shaped main body case 12 opened on the upper side. A carriage 14 that can reciprocate in the scanning direction (X direction in FIG. 2) is provided. The carriage 14 is configured to reciprocate in the main scanning direction X when the forward / reverse driving force of the carriage motor 18 is transmitted via an endless belt-like timing belt 17 wound around a pair of pulleys 15 and 16. ing.

  A recording head 19 as a discharge means (fluid discharge head) for discharging ink as fluid is attached to the lower portion of the carriage 14. A platen 20 that defines the distance between the recording head 19 and the recording paper P as a target is disposed below the recording head 19 so as to extend along the movement path of the recording head 19. Further, the recording head 19 ejects the ink of each color supplied from the black and color ink cartridges 21 and 22 detachably loaded on the carriage 14 from the nozzle group for each color.

  On the rear side of the printer 11, an automatic sheet feeder (Auto Sheet Feeder) 24 having a sheet feeding tray 23 for setting a large number of recording sheets P to be fed is provided. By driving the paper feed motor 25 disposed in the lower right portion of the main body case 12 in FIG. 1, a transport driving roller and a transport driven roller, and a paper discharge drive roller and a paper discharge driven roller (both not shown). Is rotated, and the recording paper P is conveyed in the sub-scanning direction Y. Then, a printing operation for ejecting ink from the nozzles 19a (shown in FIG. 1) of the recording head 19 toward the recording paper P while reciprocating the carriage 14 in the main scanning direction X, and the recording paper P in the sub-scanning direction Y are performed. Printing is performed on the recording paper P by alternately repeating the paper feeding operation of transporting the paper by a predetermined transport amount. In the present embodiment, the paper feed motor 25 is also used as a drive source for the automatic paper feeder 24.

  Further, the printer 11 is provided with a linear encoder 26 that outputs a number of pulses proportional to the moving distance of the carriage 14 along the guide shaft 13, and counts the pulse edges of the output pulses of the linear encoder 26. Based on the acquired carriage position, the carriage speed acquired from the count value of the number of output pulses per unit time, and the moving direction acquired from the phase difference between the two-phase output pulses, the position control and speed control of the carriage 14 are Done.

  A position corresponding to the right end portion on the movement path of the carriage 14 in the printer 11 is a home position of the carriage 14. A maintenance device 28 that performs cleaning and the like for preventing and eliminating nozzle clogging of the recording head 19 is disposed immediately below the carriage 14 that is in the home position.

  FIG. 1 is a schematic diagram showing the internal configuration of the printer 11. The printer 11 includes a controller 30 therein. The controller 30 includes an interface unit (hereinafter referred to as “I / F unit 31”), a reception buffer 32, a command interpretation unit 33, an image generation processing unit 34, a control unit 35, an image buffer 36, a nonvolatile memory 37, a driving unit 38, and the like. It has. The control unit 35 includes a calculation unit 40, a head control unit 41, and a carriage control unit 42. The drive unit 38 includes a head drive unit 43, a carriage drive unit 44, and a conveyance drive unit (not shown). The command interpretation unit 33, the image generation processing unit 34, and the control unit 35 are executed by a CPU that executes a control program stored in the ROM or an integrated circuit such as an ASIC (Application Specific Integrated Circuit). It is configured. Of course, each part 33-35 may be comprised only with software other than being constructed | assembled by cooperation of software and hardware, and may be comprised only with hardware. The reception buffer 32 and the image buffer 36 are composed of RAM.

  First, a configuration for detecting the position of the carriage 14 (carriage position) based on the output pulse of the linear encoder 26 will be described. As shown in FIG. 1, the linear encoder 26 includes a tape-shaped code plate 26 a in which a large number of slits are formed at a constant pitch (for example, 1/180 inch (= 1/180 × 2.54 cm)), and a carriage 14. It has the sensor 26b which has the provided light emitting element and light receiving element. When the carriage 14 moves, the light receiving element receives the light emitted from the light emitting element and transmitted through the code slit, so that the sensor 26b outputs a detection pulse. The controller 30 has a built-in CR position counter (not shown) that counts, for example, pulse edges of the detection pulses (two pulses that are 90 degrees out of phase between the A phase and the B phase) input from the linear encoder 26. Then, the count value of the CR position counter is incremented when the carriage moves to the non-home position side, and decremented when the carriage moves to the home position side, thereby grasping the position of the carriage 14 with the home position HP as the origin. To do.

  A host computer 50 is connected to the I / F unit 31 of the printer 11 via a communication cable. The host computer 50 has a printer driver 51 built therein. When the user selects printing execution by operating the input device 53 in order to print an image or document displayed on the monitor 52 by the display application, the printer driver 51 performs predetermined processing on the image data and performs the printer 11. Print data (discharge instruction data) that can be handled by the printer. At this time, the print conditions input and set by the user on the print setting screen displayed on the monitor 52 include paper type, paper size, print quality, color / monochrome, layout, bidirectional printing, and the like. Corresponding print data is generated. The print data includes a header in which a control command is described and print image data that is raster data of an image to be printed.

  The print image data is generated when the printer driver 51 performs color conversion processing, resolution conversion processing, halftone processing, rasterization processing, and the like on image data of a color system for monitor display (for example, RGB color system). . Here, the color conversion process is a process of converting image data of a monitor display color system (for example, RGB color system) into image data of a CMYK color system. The resolution conversion process is a process for converting the image resolution for monitor display into the print resolution of the printer. Halftone processing includes gradation value conversion that converts continuous gradation (for example, 256 gradations) representing the density of dots into a predetermined gradation (for example, 2 gradations or 4 gradations) that can be expressed by the printer. It is processing. For example, if the ink droplet has a function of hitting a plurality of large, medium, and small dot sizes, it is converted into four gradations. The rasterization process is a process of rearranging the dot arrangement of data in the dot formation order (ink ejection order) that matches the recording method. For example, microweave processing for rearranging in the dot formation order of the interlaced recording method can be mentioned.

  The control commands described in the header are created based on the print condition data and the print image data, and carry system commands such as a paper feed operation, a paper feed operation, and a paper discharge operation, a carriage operation, and a print head. It consists of various commands such as printing commands such as operation (recording operation). Further, the print mode is determined based on the print condition data. In the present embodiment, as a print mode, a high-speed print mode that gives priority to the print speed over the print image quality, a high-quality print mode that gives priority to the print image quality over the print speed (low-speed print mode), and an intermediate print performance between these two modes. There are three modes: a standard printing mode (medium speed printing mode). In this example, “bidirectional printing” can be selected as the printing condition in all three modes. Of course, for example, it may be configured such that designation of bidirectional printing, which is difficult to obtain high image quality, is not possible in the high image quality printing mode. Note that the printer driver 51 transmits print data to the printer 11 in units of packets for each row (one main scanning line).

The reception buffer 32 shown in FIG. 1 is a recording area in which print data received via the I / F unit 31 is temporarily stored.
The command interpreter 33 reads the header of the print data from the reception buffer 32, acquires the control command and the like therein, and interprets the control command described in the printer description language. The command interpretation result is sent to the head controller 41 and the carriage controller 42 of the controller 35.

  The image generation processing unit 34 reads the print image data in the print data from the reception buffer 32 one line at a time (main scanning line), and based on the print image data, the print start position with the carriage movement path as the origin as the scale PS and print end position PE are calculated. Here, the print start position PS refers to the recording start position (first dot recording position) in the forward path of the carriage 14, and the print end position PE refers to the dot recording end position (final dot recording position) in the forward path of the carriage 14. Point to. In the return path of the carriage 14, the print end position PE is the print start position, and the print start position PS is the print end position.

  The calculation unit 40 is a part that calculates the ink discharge start position of the recording head 19, and includes a first discharge position calculation unit 46, a second discharge position calculation unit 47, and a carriage control position calculation unit 48. The first ejection position calculation unit 46 calculates the ink ejection start position ISa in the forward path of the recording head 19. Further, the second ejection position calculation unit 47 calculates the ink ejection start position ISb in the return path of the recording head 19. Further, the carriage control position calculation unit 48 calculates a starting position (hereinafter referred to as “carriage starting position”) at which the carriage 14 starts to move for a one-pass printing operation.

  The nonvolatile memory 37 includes a discharge start position adjustment table DT1 (see FIG. 3A), a Bi-D adjustment table DT2 (see FIG. 3B), and a carriage acceleration / deceleration that the calculation unit 40 refers to at the time of calculation. Data AD (see FIG. 6) is stored. The discharge start position adjustment data DT1 is a table that is referred to when the first discharge position calculation unit 46 calculates the ink discharge start position ISa, and a plurality of discharge start position adjustment data DT1 corresponding to the carriage speed Vcr as shown in FIG. Value is set. In this example, as shown in FIG. 3A, the discharge start position adjustment values αlow, αmid, and αhigh are set in association with the three types of carriage speeds Vlow, Vmid, and Vhigh corresponding to each printing mode. ing. Of course, these adjustment values can be set in association with modes such as the speed mode and the print mode. In this embodiment, the discharge start position adjustment values αlow, αmid, and αhigh correspond to the first adjustment amount.

  First, the forward discharge start position adjustment value will be described with reference to FIG. In FIG. 4, the rightward movement is the outward path. As shown in FIG. 4A, the ink droplet 55 ejected from the nozzle 19a of the recording head 19 at the carriage speed Vlow moves in the carriage movement direction before landing on the recording paper P due to the carriage speed component. Lands at a position shifted by a distance Rlow in the forward direction from the discharge start position.

  By the way, the distance Rlow depends on a combined vector of the vector of the ink droplet ejection speed Vi and the vector of the carriage speed Vcr. As shown in FIG. 4 (a), when ink droplets are ejected from a constant carriage position at a constant ink droplet ejection speed Vi, the landing positions at both a high carriage speed Vhigh and a low carriage speed Vlow. Shifts by a distance Δ. In the present embodiment, the ink discharge start position is adjusted according to the carriage speed Vk (k = low, mid, high) so as to eliminate the deviation of the print start position due to this kind of carriage speed difference. . As the adjustment value, the discharge start position adjustment value αk is adopted.

  Here, as shown in FIG. 4B, the carriage is shifted to the position opposite to the carriage movement direction by the distance Δ in FIG. 4A with respect to the ink discharge start position at the low speed Vlow. If the ink discharge start position when the speed is high Vhigh is set, the print start position at high speed coincides with the print start position at low speed. That is, the discharge start position adjustment values αlow and αhigh are set according to the carriage speeds Vlow and Vhigh so that αhigh = αlow−Δ, and the adjustment values αlow and αhigh according to the carriage speeds Vlow and Vhigh are used. If the ink discharge start position ISalow = PS−αlow and ISahigh = PS−αhigh are set, the print start position can be made the same regardless of the difference between the carriage speeds Vlow and Vhigh. In this example, the distance between the ink discharge start position and the print recording start position, which differs depending on the carriage speed Vk, is set as the discharge start position adjustment value αk.

  The discharge start position adjustment value αk is set, for example, in a process inspection in the printer manufacturing process. In this process inspection, an inspection pattern (patch) is printed at a reference carriage speed (for example, a low speed Vlow) and another carriage speed. Then, the distance corresponding to the deviation of the inspection pattern printed on the sheet for each speed is measured, and an adjustment value corresponding to the measured value is set as an ejection start position adjustment value for each carriage speed. This adjustment value can be measured by an inspector using a measuring instrument, or by automatically reading the discharge start position for each carriage speed by reading the print pattern on the paper using an image sensor mounted on the carriage. A method of obtaining the discharge start position adjustment value using a corresponding value may be used. In addition, as one of the initialization processes when the user first activates the printer after purchasing the printer, or as one of the maintenance periodically performed by the user, the ejection start for printing the test pattern and detecting the displacement by the sensor is started. The position adjustment value setting process may be executed to automatically set each adjustment value.

The first discharge position calculation unit 46 refers to the discharge start position adjustment table DT1, acquires the discharge start position adjustment value αk corresponding to the designated carriage speed Vk, and uses the discharge start position adjustment value αk. The ink discharge start position ISa is calculated by the following formula.
ISa = PS−αk (1)
Here, PS is a print start position in the forward path of the carriage.

  Further, the Bi-D adjustment table DT2 stored in the non-volatile memory 37 is a table for the second ejection position calculation unit 47 to refer to when calculating the ink ejection start position ISb, and is shown in FIG. As shown, a plurality of Bi-D adjustment values corresponding to the carriage speed are set. That is, as shown in FIG. 3B, the Bi-D adjustment values βlow, βmid, and βhigh are set in association with the three types of carriage speeds Vlow, Vmid, and Vhigh corresponding to the printing mode, respectively. Of course, these Bi-D adjustment values can be set in association with the speed mode and the print mode. In the present embodiment, the Bi-D adjustment values βlow, βmid, and βhigh correspond to the second adjustment amount.

  Next, the Bi-D adjustment value will be described with reference to FIG. In FIG. 5, movement in the right direction is the forward path, and movement in the left direction is the backward path. As shown in FIGS. 5A and 5B, the printing position (landing position) by the ink droplet 55 ejected from the nozzle 19 a of the recording head 19 in the forward path of the carriage 14 and the nozzle of the recording head 19 in the return path of the carriage 14. In order to match the printing position (landing position) by the ink droplet 55 ejected from 19a, the ejection start position is determined so that the ejection of the ink droplet can be started at a timing position earlier than the target landing position in the return path. There is a need. The adjustment value for determining the discharge start position with respect to the target landing position is the Bi-D adjustment value βk, and the larger the value βk as the carriage speed Vk becomes higher as shown in FIGS. 5 (a) and 5 (b). It is necessary to. A small Bi-D adjustment value βlow is set at a low carriage speed Vlow shown in FIG. 5A, and a large Bi-D adjustment value βhigh is set at a high carriage speed Vhigh shown in FIG. The ink discharge start position in the backward path is an adjustment amount that is adjusted with respect to the forward print end position PE so that the forward print end position PE becomes the landing start position in the backward path. It is stored as the D adjustment value β. For example, the return discharge start position ISblow at a low carriage speed Vlow shown in FIG. 5A is expressed as ISblow = PE + βlow, and the return discharge start position ISbhigh at a high carriage speed Vhigh shown in FIG. ISbhigh = PE + βhigh.

  Since this Bi-D adjustment value β also depends on the carriage speed Vcr, it is set in association with each carriage speed Vlow, Vmid, Vhigh. The Bi-D adjustment value is set by, for example, a process inspection in the printer manufacturing process. First, bidirectional printing is performed at each carriage speed, and a plurality of inspection patterns (patches) having different Bi-D adjustment values are printed on a sheet. The number corresponding to the print pattern with almost zero print deviation between the forward path and the backward path among the plurality of test patterns printed on the paper is input and set to the printer, and this is set for each carriage speed. The memory 37 stores a Bi-D adjustment table DT2. Of course, the inspector measures the printing deviation of the inspection pattern using a measuring instrument, or reads the inspection pattern on the paper by the image sensor mounted on the carriage 14 to automatically measure the positional deviation in the forward path and the backward path. Alternatively, a method of setting a Bi-D adjustment value according to the measurement value may be used. In addition, as one of initialization processes executed at the first start after purchase of the printer or as one of maintenance periodically performed by the user, Bi-D adjustment is performed by printing a test pattern and detecting misalignment by a sensor. A configuration in which values are automatically set can also be adopted.

The second discharge position calculation unit 47 refers to the Bi-D adjustment table DT2, acquires the Bi-D adjustment value βk corresponding to the designated carriage speed Vk, and uses the Bi-D adjustment value βk, The ink discharge start position ISb is calculated by the following formula.
ISb = PE + βk (2)
Here, PE is the printing end position on the return path of the carriage 14.

The ink discharge start position ISa calculated by the first discharge position calculation unit 46 and the ink discharge start position ISb calculated by the second discharge position calculation unit 47 are set in the head control unit 41.
The head control unit 41 controls the recording head 19 via the head driving unit 43. Print image data (raster data) for one pass or two passes is prepared in the image buffer 36, and print image data for one pass is output to the head driving unit 43 every time the printing operation is completed.

  The head control unit 41 generates a reference pulse of a discharge timing pulse based on an encoder pulse input from the linear encoder 26 during driving of the carriage, and generates a counting pulse having a sufficiently shorter cycle than the discharge timing pulse. A two-signal generation unit, and a discharge signal generation unit (not shown) that starts counting counting pulses using the input of the reference pulse as a trigger and outputs a discharge timing signal when the count value reaches a target value Have. By setting the target value for counting pulses according to the Bi-D adjustment value, when the value corresponding to the ink ejection start position ISa or ISb is reached, the first ejection timing pulse is output and the forward path or the backward path Ink droplet ejection is started. The recording head 19 has a built-in discharge drive element for each nozzle. When the dot value of the print image data is “1”, for example, a voltage having a predetermined drive waveform is applied to the discharge drive element and the ink from the nozzle 19a. On the other hand, when the dot value of the print image data is “0”, for example, no voltage is applied to the ejection drive element, and no ink droplet is ejected from the nozzle. Examples of the ejection driving element include a piezoelectric driving element (piezo element), an electrostatic driving element, and a heater that heats ink and ejects ink droplets from nozzles using the pressure of bubbles caused by film boiling. be able to.

  The carriage control unit 42 controls driving of the carriage motor 18 via the carriage driving unit 44. Of the printing commands interpreted by the command interpretation unit 33, commands relating to the carriage operation are passed to the carriage control unit. The carriage control unit 42 is set with a control position such as a carriage start position (hereinafter referred to as “CR start position Scr”) calculated by the carriage control position calculation unit 48 (see FIG. 9). The carriage control unit 42 moves the carriage 14 from the previous pass end position (carriage stop position) to the carriage start position to stand by, and when the paper feed operation end timing or a predetermined start timing slightly earlier than that, the carriage motor 18. Is started to start the carriage 14.

  FIG. 6 shows a carriage speed profile. In the present embodiment, as shown in FIG. 6, an acceleration table AD1 and a deceleration table AD2 necessary for defining each speed profile according to three types of printing modes are stored in the nonvolatile memory 37. In the case of this example, the acceleration distance from the carriage start position “0” to the target speed (Vlow, Vmid, Vhigh) at any target speed Vlow, Vmid, Vhigh is from the deceleration start position DS to the carriage stop position Ecr. It is at least longer than the deceleration distance.

  FIG. 7 shows the carriage operation area diagram and the forward and backward acceleration profiles. In FIG. 7, the upper part shows the carriage operation diagram, and the lower part shows the acceleration profile of the forward path and the backward path. An area in which the carriage 14 can operate (hereinafter referred to as “carriage operation area”) is secured in the main body case 12 of the printer 11. In the carriage operation area diagram of FIG. 7, the left end position is the home position HP and the right end position is the anti-home position OP, which are the end positions on both sides in the carriage movement direction, and this is the carriage operation area. Of the carriage operation area, the area between the home positions HP and HE is used for maintenance and the like, and the position between the positions HE and OP is a carriage operation area for printing. In the carriage operation area for printing, the forward carriage acceleration area AC1, the discharge start position adjustment area ISA, the print area PA, the Bi-D adjustment area BA, and the return carriage acceleration area AC2 are set from the home position HP side. ing. The carriage acceleration areas AC1 and AC2 are secured by the maximum acceleration distance of the carriage 14 required to reach the target speed Vhigh with an acceleration profile that targets the high-speed carriage speed Vhigh. The discharge start position adjustment area ISA is an area for setting the ink discharge start position in the forward path within this area, and has an area comparable to the maximum discharge start position adjustment value αhigh. The print area PA is an area where printing is performed, and is set slightly wider than the paper width of the maximum paper size that the printer 11 can handle. The Bi-D adjustment area BA is an area for setting the ink discharge start position in the return path within this area, and has a size comparable to the maximum Bi-D adjustment value βhigh (= αhigh). The discharge start position adjustment area ISA and the Bi-D adjustment area BA are the same size.

  Here, for example, when the carriage ink speed is increased under the condition that the ink discharge start position in the forward path is a constant position regardless of the carriage speed due to a request for speeding up the carriage, the print end position of the forward path is shifted toward the forward path traveling direction. Moreover, since it is necessary to increase the Bi-D adjustment value in accordance with the increase in speed, it is necessary to increase the Bi-D adjustment area to the non-home side. However, in this embodiment, adjustment is performed to shift the forward discharge start position to the home position HP side as the carriage speed increases. Therefore, the maximum Bi-D adjustment value becomes larger as compared with the prior art as the speed increases. The forward print end position is determined by the print end position PE determined from the print image data, and there is no shift amount to the non-home position OP side. Therefore, the increment of the Bi-D adjustment value can be suppressed as small as possible. For this reason, even if it is within the conventional Bi-D adjustment area BA or increases, the increment is small, so there is no need to increase the carriage operation area, and an increase in the width of the printer 11 in the width direction is avoided.

  Usually, the printing area PA is set at a substantially central position in the carriage operation area for printing. For this reason, if it is intended to increase the carriage speed only by the Bi-D adjustment value, it is necessary to widen only the space on the right side of the print area in FIG. 7 for the Bi-D adjustment area BA. For example, in a configuration in which only one side is increased, if it cannot be increased any longer, a design change is required to shift the print area PA to the left side in FIG. 7 in order to secure a space on the right side. In this case, it is necessary to change the position of the paper feed tray, the position of the paper discharge port, and the like in accordance with the position of the print area. However, according to the configuration of the present embodiment, the space on both sides of the print region can be used in a balanced manner between the discharge start position adjustment region and the Bi-D adjustment value, so that such a problem can be avoided. .

  Next, the operation of the printer configured as described above will be described according to the flowchart shown in FIG. 8 with reference to FIG. The program shown in the flowchart of FIG. 8 is executed by the control unit 35 during the printing operation. The I / F unit 31 of the printer 11 receives print data for each line (one main scanning line) from the printer driver of the host computer. The received print data is temporarily stored in the reception buffer 32, and the command interpretation unit 33 interprets the control command, and the image generation processing unit 34 reads the print image data for one line, processes the print image data, The print start position PS and the print end position PE in the line are calculated.

  Further, the control unit 35 grasps that the current printing process is bidirectional printing and the instructed speed mode (or carriage speed Vk) based on the command interpretation result of the command interpretation unit 33. Further, the control unit 35 knows whether the printing operation for the next pass is the forward pass or the return pass. Although an example in which one line is printed with two passes of the forward path and the backward path will be described, a configuration may be adopted in which printing is performed for each line on the forward path and the backward path. In the latter case, the print start position PS and the print end position PE of one line on the forward path side are newly calculated prior to printing on the forward path side, and the ink discharge start position and the like are calculated based on these positions PS and PE. Become.

First, in step S10, the print start position PS and the print end position PE sent from the image generation processing unit 34 are set in the control unit 35.
In step S20, the discharge start position adjustment value αk and the Bi-D adjustment value βk corresponding to the carriage speed Vk are read from the nonvolatile memory 37 with reference to the tables DT1 and DT2.

  In step S30, it is determined whether or not it is forward printing. If it is forward printing, the process proceeds to step S40, and if it is not forward printing (that is, if it is backward printing), the process proceeds to step S50. For example, if this time is forward printing, the ink discharge start position ISa is calculated using the print start position PS and the discharge start position adjustment value αk in step S40 (ISa = PS−αk). The process of step S40 corresponds to the first adjustment step.

In the next step S60, the ink discharge start position ISa is set in the head controller 41.
In step S70, the carriage start position is set in the carriage controller 42.

  In step S80, a printing operation is executed. That is, the carriage control unit 42 controls the carriage motor 18 to move the carriage 14 to the CR start position Scr and starts the carriage 14 from the CR start position Scr when the print operation start timing comes. During acceleration of the carriage 14, the carriage control unit 42 controls acceleration of the carriage motor 18 with reference to acceleration data corresponding to the speed mode at that time. Then, after the carriage 14 reaches the target speed Vk, when the head control unit 41 confirms that the recording head 19 has reached the ink discharge start position ISa, it outputs a discharge start command to the head drive unit 43 to output the recording head 19. Ink droplet ejection is started. Specifically, recording is performed based on the first ejection timing pulse input to the head driving unit 43 when the count value obtained by the head control unit 41 internally counting the number of pulses of the counting pulse triggered by the input of the reference pulse reaches a target value. Ink ejection from the head 19 is started. Thereafter, each time the carriage 14 advances by a predetermined pitch corresponding to the printing resolution, the next ejection timing pulse is input to the head drive unit 43, whereby the print head 19 performs forward printing.

Here, as a result of determining whether or not forward printing is performed in step S <b> 30, if the forward printing is performed, the control unit 35 sets “1” in the forward printing flag.
When the forward printing is completed, the process returns to step S10. However, if the forward printing flag is “1”, the process of step S10 is performed last time, and the printing start position PS and the printing end position PE have already been set. Further, since the speed mode is the same during the execution of the same print job, the process of step S20 has already been performed with the data reading process of step S20, and is omitted if the read flag is “1”. For this reason, after finishing the forward printing, the processes of steps S10 and S20 are omitted, and the process proceeds to step S30.

Then, in step S30, it is determined whether or not the forward printing is performed. Since this time is the backward printing, the process proceeds to step S50.
In step S50, the ink discharge start position ISb (= PE + βk) in the return path is calculated using the print end position PE and the Bi-D adjustment value βk corresponding to the designated carriage speed Vk.

  As in the forward printing, the ink ejection start position ISb is set in the head controller 41 (S60), the CR start position is calculated and set in the carriage controller 42 (S70), and the printing operation is executed. (S80).

  Here, as shown in FIG. 9, the calculation of various control positions on the speed profile is performed as follows. The control positions include a CR start position Scr, an ink discharge start position ISa, an ink discharge end position IE (= PE−αk), a deceleration start position DS, a carriage stop position Ecr, and the like.

  FIG. 9A is a graph for explaining the case of the forward path. When the print start position PS is determined, the ink discharge start position ISa is calculated using the discharge start position adjustment value αk corresponding to the carriage speed Vk (ISa = PS−αk). Then, the CR start position Scr of the forward path is calculated by subtracting the acceleration distance Racc determined from the acceleration data of the designated carriage speed Vk from the ink discharge start position ISa (Scr = ISa−Racc). Further, the deceleration start position DS is calculated by adding the maximum value βmax (for example, βmax = βhigh) of the Bi-D adjustment value to the print end position PE (DS = PE + βmax). Further, the carriage stop position Ecr is calculated by adding the deceleration distance Rdec determined from the deceleration data to the deceleration start position DS. Here, when the deceleration start position is determined, the maximum value βmax of the Bi-D adjustment value is added because the carriage 14 moves from the forward stop position Ecr even when the carriage speed on the return path is the highest speed Vhigh. This is to ensure the Bi-D adjustment value βk necessary when starting. Of course, instead of adding the maximum value βmax of the Bi-D adjustment value, a Bi-D adjustment value βk corresponding to the carriage speed Vk designated at that time may be added.

  FIG. 9B is a graph for explaining the case of the return path. In the case of the return path, the ink discharge start position ISb is calculated by adding the Bi-D adjustment value βk corresponding to the carriage speed Vk to the print end position PE (ISb = PE + βk). Then, the CR start position Scr of the return path is calculated from the ink discharge start position ISb by adding the acceleration distance Racc determined from the acceleration data of the carriage speed Vk at that time (Scr = ISb + Racc). Further, the deceleration start position DS is calculated by subtracting the maximum value αmax (for example, αmax = αhigh) of the discharge start position adjustment value from the print start position PS that is the print end position of the return pass (DS = PS−αmax). Further, the carriage stop position Ecr is calculated by subtracting the deceleration distance Rdec determined from the deceleration data from the deceleration start position DS. Here, when the deceleration start position is determined, the maximum value αmax of the discharge start position adjustment value is subtracted from the return path stop position Ecr to the carriage 14 even when the carriage speed in the next forward path is the highest speed Vhigh. This is for ensuring the necessary discharge start position adjustment value αk when the engine is started. Of course, instead of subtracting the maximum value αmax of the discharge start position adjustment value, it is possible to add only the discharge start position adjustment value αk corresponding to the carriage speed Vk specified at that time.

  In this embodiment, the landing position deviation correction for the return path with respect to the outbound path is executed for the landing position of the outbound path adjusted with the discharge start position adjustment value αk. For this reason, the Bi-D adjustment value βk needs to be a small value for the carriage speed Vcr. Further, since the ink discharge start position ISa is determined using the discharge start position adjustment value αk corresponding to the carriage speed Vk with respect to the print start position PS, the ink discharge start position ISa is always from the same position on the recording paper P regardless of the carriage speed Vk. Printing can be started. Therefore, when the same image is printed on the same size paper, it is possible to eliminate the situation where the landing position is shifted in the paper width direction according to the print mode (speed mode). Therefore, in any print mode, an image can be printed at the same position in the main scanning direction of the recording paper P. For example, when marginless printing is performed in the high-speed printing mode, it is possible to effectively prevent a slight margin from being formed on the side edge of the paper.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) Since the ink discharge start position ISa is adjusted according to the carriage speed Vk using the discharge start position adjustment value αk corresponding to the designated carriage speed Vk, bidirectional printing is performed regardless of the carriage speed (speed mode). The printed image can be always printed at the same position without being shifted in the main scanning direction of the recording paper P.

  (2) The return landing position deviation correction (Bi-D adjustment) with respect to the forward path is performed on the print end position PE when the forward ink ejection start position ISa adjusted with the ejection start position adjustment value αk is adjusted, The Bi-D adjustment value βk corresponding to the carriage speed Vk is subtracted from the print end position PE to determine the return ink ejection start position ISb. For this reason, even if the carriage speed is increased, the print end position of the forward path does not shift to the forward travel direction side, so the Bi-D adjustment area necessary for securing the necessary Bi-D adjustment value βk. The BA increment can be kept small.

  (3) Since the discharge start position adjustment value αk and the Bi-D adjustment value β in bidirectional printing are set to be substantially equal at any carriage speed, the space on both sides of the print area PA is set as the discharge start position. The adjustment area ISA and the Bi-D adjustment area BA can be used in a balanced manner. Therefore, a change that increases the carriage operation area in the main scanning direction X and a change in the position of the print area in the carriage operation area hardly occur. For this reason, an increase in the size of the printer 11 in the width direction (main scanning direction) due to an increase in the carriage operation area, or an automatic paper feeder that should be arranged at a position corresponding to the printing area in the main scanning direction X of the printer 11. 24 and the position change of the paper discharge tray in the main scanning direction X can be avoided.

(Second embodiment)
Next, a second embodiment will be described. In the present embodiment, only one Bi-D adjustment value is set. As shown in FIG. 10A, the non-volatile memory 37 stores a reference discharge start position adjustment value αo and a reference Bi-D adjustment value βo corresponding to the reference carriage speed Vo as the reference movement speed. Further, the nonvolatile memory 37 stores a conversion table DT3 shown in FIG. In the conversion table DT3, conversion values for adjusting the discharge start position and conversion values for Bi-D adjustment are set in association with the carriage speeds Vlow, Vmid, and Vhigh. That is, conversion values Mlow, Mmid, and Mhigh for adjusting the discharge start position are set in association with the carriage speeds Vlow, Vmid, and Vhigh. Also, Bi-D adjustment conversion values Nlow, Nmid, and Nhigh are set in association with the carriage speeds Vlow, Vmid, and Vhigh. If the reference carriage speed Vo is, for example, the medium speed Vmid, the conversion values for adjusting the discharge start position are set to Mlow = 0.6, Mmid = 1, Mhigh = 1.3, for example, and Bi-D adjustment. For example, Nlow = 0.6, Nmid = 1, and Nhigh = 1.3 are set as the conversion values.

The discharge start position adjustment value αk is calculated by the following equation.
αk = α0 × Mk
Here, αo is a reference discharge start position adjustment value, and Mk is a conversion value for discharge start position adjustment corresponding to the carriage speed Vk.

Further, the Bi-D adjustment value βk is calculated by the following equation.
βk = β0 × Nk
Here, βo is a reference discharge start position adjustment value, and Nk is a converted value for Bi-D adjustment corresponding to the carriage speed Vk.

  Then, using the discharge start position adjustment value αk and the Bi-D adjustment value βk corresponding to the carriage speed Vk, the ink discharge start position is calculated using the equations (1) and (2) in the first embodiment. ISa and ISb are calculated.

  According to this configuration, it is only necessary to set the discharge start adjustment value and the Bi-D adjustment value for only one carriage speed as a reference, and it is possible to reduce the labor for setting work and to store the adjustment value. The area can be reduced. As a method for setting the discharge start adjustment value and the Bi-D adjustment value, for example, when a patch is printed at a reference carriage speed and the number of the condition with the smallest recording position deviation is input from the patch print result, There is a method in which the corresponding discharge start adjustment value and Bi-D adjustment value are set.

In addition, embodiment is not limited above, You may change as follows.
(Modification 1) A difference table DT4 as shown in FIG. 11 may be employed. The reference ejection start position adjustment value α0 and the reference Bi-D adjustment value βo corresponding to the reference carriage speed in FIG. 10A are stored in the nonvolatile memory 37 as in the second embodiment. In this table DT4, differences Δαk and Δβk with respect to the reference ejection start position adjustment value αo and the reference Bi-D adjustment value βo are set in association with the carriage speed Vk. That is, the differences Δαlow, Δαmid, Δαhigh for adjusting the discharge start position are set in association with the carriage speeds Vlow, Vmid, Vhigh. Further, Bi-D adjustment differences Δβlow, Δβmid, and Δβhigh are set in association with the carriage speeds Vlow, Vmid, and Vhigh. The discharge start position adjustment value αk is calculated by the equation αk = α0−Δαk. Here, αo is a reference discharge start position adjustment value, and Δαk is a difference for discharge start position adjustment corresponding to the carriage speed Vk. Further, the Bi-D adjustment value βk is calculated by the equation βk = β0 + Δβk. Here, βo is a reference discharge start position adjustment value, and Δβk is a Bi-D adjustment difference corresponding to the carriage speed Vk. Then, using the discharge start position adjustment value αk and the Bi-D adjustment value βk corresponding to the carriage speed Vk, the ink discharge start position is calculated using the equations (1) and (2) in the first embodiment. ISa and ISb are calculated. Even in this configuration, the same effect as in the second embodiment can be obtained.

  (Modification 2) The discharge start position adjustment value αk and the Bi-D adjustment value βk are not limited to being set to substantially the same value. As long as the ejection start position adjustment value αk (and hence the ink ejection start position ISa) is changed according to the carriage speed, the ejection start position adjustment value αk can be set to an arbitrary value. For example, as long as the carriage start speed Vk is higher, the discharge start position adjustment value αk is set to be larger. The print start position when ink is discharged from the ink discharge start position determined from the discharge start position adjustment value αk is the difference in the carriage speed. Depending on the case, the configuration may be shifted slightly.

  (Modification 3) The configuration in which the forward path and the backward path in the above embodiment are reversed may be used. That is, the direction from the non-home side to the home side is the forward path, and the direction from the home side to the anti-home side is the backward path. The forward path refers to movement in the carriage movement direction in which first dots are formed.

  (Modification 4) The recording execution speed is not limited to a constant speed. Acceleration / deceleration printing that starts ink ejection from the middle of acceleration and continues ink ejection to the middle of deceleration can be adopted, and the carriage speed can be changed in the first few areas and the last few areas of the recording execution speed. .

  (Modification 5) In the case where a plurality of types of ink sizes (for example, large, medium, and small) are distinguished, a configuration in which the ejection start position adjustment value αk and the Bi-D adjustment value βk corresponding to the carriage speed are set for each ink size is also employed. it can. In this case, even when bidirectional printing is performed with a plurality of types of ink sizes, the recording position can be effectively suppressed, and the printing position of the recording paper P in the main scanning direction X due to the difference in the carriage speed. The shift can be effectively suppressed.

  (Modification 6) In the above-described embodiment, the fluid discharge device is embodied as an ink jet recording device. However, the present invention is not limited to this, and fluid other than ink (liquid or particles of functional material are dispersed or mixed in the liquid). And a fluid discharge device that discharges a liquid, a fluid such as a gel, and a solid that can be discharged and discharged as a fluid. For example, a liquid material ejecting apparatus that ejects a liquid material in the form of dispersed or dissolved materials such as electrode materials and color materials (pixel materials) used for manufacturing liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays. Further, it may be a liquid ejecting apparatus for ejecting a bio-organic material used for biochip manufacturing, or a liquid ejecting apparatus for ejecting a liquid as a sample used as a precision pipette. In addition, a transparent resin liquid such as UV curable resin is used to form a liquid ejection device that ejects lubricating oil pinpoint to precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. Liquid ejecting apparatus for ejecting a liquid onto a substrate, liquid ejecting apparatus for ejecting an etching solution such as acid or alkali to etch the substrate, etc., and a fluid ejecting apparatus for ejecting a fluid such as a gel (for example, physical gel) Further, it may be a powder particle discharge device (for example, a toner jet recording device) that discharges a solid such as powder (powder particles) such as toner. The present invention can be applied to a configuration in which bidirectional recording is performed in any one of these fluid ejection devices. In the present specification, the term “fluid” is a concept that does not include a fluid consisting only of gas. Examples of the fluid include liquid (inorganic solvent, organic solvent, solution, liquid resin, liquid metal (metal melt), etc. ), Liquids, fluids, powders (including granules and powders), and the like.

FIG. 2 is a block diagram illustrating an electrical configuration of the printer according to the first embodiment. FIG. (A) Discharge start position adjustment table, (b) Bi-D adjustment table. (A) (b) Explanatory drawing regarding discharge start position adjustment. (A) (b) Explanatory drawing regarding Bi-D adjustment. The graph which shows a carriage speed profile. FIG. 6 is a flowchart illustrating ink discharge start position adjustment processing in bidirectional printing. (A) The graph which shows the speed profile of an outward path and (b) a return path, respectively. The (a) reference | standard data figure in 2nd embodiment, (b) The conversion table figure. The difference table figure in a modification.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Printer as fluid discharge apparatus, 14 ... Carriage which comprises discharge means, 17 ... Timing belt which comprises movement means, 18 ... Carriage motor which comprises movement means, 19 ... Recording head which comprises discharge means, 19a ... Nozzle, 25 ... paper feed motor, 26 ... linear encoder, 33 ... command interpreting unit, 34 ... image generation processing unit, 35 ... control unit constituting control means, 36 ... image buffer, 37 ... nonvolatile memory, 38 ... drive , 40... Calculation unit, 41... Head control unit, 42... Carriage control unit, 43... Head drive unit, 44 ... Carriage drive unit, 46 ... First discharge position calculation unit constituting first adjustment means, 47. Second discharge position calculation unit constituting second adjustment means, 48... Carriage control position calculation unit, P... Recording paper as target, DT1. Start position adjustment table, DT2... Bi-D adjustment table, Vlow, Vmid, Vhigh... Carriage speed (target speed) as moving speed, .alpha.low, .alpha.mid, .alpha.high. ISa: ink discharge start position as a fluid discharge start position in the forward path, ISb: ink discharge start position as a fluid discharge start position in the return path, βlow, βmid, βhigh: Bi-D adjustment values as second adjustment amounts, D1 ... reference data, DT3 ... conversion table, DT4 ... difference table.

Claims (7)

Discharge means for discharging a fluid to the target;
Moving means for reciprocating the discharge means in the scanning direction;
A fluid ejection apparatus comprising: a control unit that controls the ejection unit and the movement unit to perform bidirectional recording and controls the ejection unit at a designated one movement speed among a plurality of movement speeds;
In order to reduce the deviation of the recording position of the forward path of the ejection unit with respect to the target between the plurality of moving speeds, the fluid discharge start position in the forward path of the ejection unit with respect to the recording start position of the forward path determined from the given ejection instruction data, First adjusting means for adjusting according to a designated moving speed of the discharge means;
The fluid discharge start position in the return path is set in accordance with the designated moving speed so as to reduce the deviation of the recording position in the return path from the recording position of the forward path determined from the fluid discharge start position adjusted by the first adjusting means. And a second adjusting means for adjusting the fluid.   The first adjusting means adjusts the fluid discharge start position in the forward path according to a designated moving speed of the discharge means so that recording starts from a recording start position determined from discharge instruction data on the target. The fluid ejection device according to claim 1, wherein: The first adjusting means sets a shift amount to be shifted in the opposite direction of the forward path to determine the fluid discharge start position with respect to the recording start position in the forward path determined from the discharge instruction data according to the designated moving speed. A first adjustment amount, the fluid discharge start position is adjusted to a position shifted in the opposite direction of the forward path with respect to the recording start position,
The second adjusting means specifies the shift amount to be shifted in the opposite direction of the return path to determine the return start position of the return path from the fluid discharge start position to the recording end position when the discharge means discharges the fluid. The second adjustment amount is obtained according to the travel speed, and the discharge start position is obtained by adjusting the second adjustment amount in a direction opposite to the backward movement direction with respect to the recording end position. The fluid ejection device according to claim 2.   The first adjustment amount in the forward path determined by the first adjusting means according to the moving speed and the second adjustment amount in the return path determined by the second adjusting means according to the moving speed are substantially equal. The fluid ejection device according to claim 3, wherein the fluid ejection device is set to be. In the second adjustment means, a second reference adjustment amount is set as a second adjustment amount corresponding to a reference movement speed to be a reference among the plurality of movement speeds,
When a movement speed different from the reference movement speed is designated, the second reference adjustment amount is converted according to a speed ratio between the designated movement speed and the reference movement speed. 5. The fluid ejection device according to claim 1, wherein a second adjustment amount corresponding to the moving speed is acquired. In the first adjustment means, a first reference adjustment amount is set as the first adjustment amount corresponding to a reference movement speed among the plurality of movement speeds,
When a movement speed different from the reference movement speed is designated, the first reference adjustment amount is converted according to a speed ratio between the designated movement speed and the reference movement speed. The fluid ejection device according to claim 1, wherein a first adjustment amount corresponding to the moving speed is acquired. A discharge means for discharging a fluid to the target, a moving means for reciprocating the discharge means in the scanning direction, and controlling the discharge means and the moving means to perform bidirectional recording and moving the discharge means for a plurality of movements A bidirectional recording method in a fluid ejection device comprising a control means for controlling at a designated moving speed of the speed,
In order to reduce the deviation of the recording position of the forward path of the ejection unit with respect to the target between the plurality of moving speeds, the fluid discharge start position in the forward path of the ejection unit with respect to the recording start position of the forward path determined from the given ejection instruction data, A first adjustment step of adjusting according to a designated moving speed of the discharge means;
The fluid discharge start position in the return path is set in accordance with the designated moving speed so as to reduce the deviation of the recording position in the return path from the recording position of the forward path determined from the fluid discharge start position adjusted in the first adjustment step. A bidirectional recording method in a fluid ejection apparatus, comprising: a second adjustment step for adjustment.

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