JP7172444B2 - Liquid ejector - Google Patents

Description

The present invention relates to a liquid ejecting apparatus that ejects liquid from nozzles.

2. Description of the Related Art As a liquid ejecting apparatus that ejects liquid from nozzles, Japanese Patent Application Laid-Open No. 2002-200001 describes an inkjet recording apparatus that performs recording by ejecting ink from nozzles. In the inkjet printing apparatus disclosed in Japanese Patent Application Laid-Open No. 2002-200010, printing is performed by ejecting ink from a printing head mounted on the carriage while moving the carriage in the scanning direction. Further, in the inkjet printing apparatus of Patent Document 1, after adjusting the temperature of the printing head to each of a plurality of different temperatures (30° C. and 50° C.), an adjustment pattern for adjusting the ink landing position in the scanning direction is used. are recorded respectively. Then, the ink ejection timing is determined based on the printing result of the adjustment pattern.

JP 2010-143115

However, Patent Document 1 does not describe any specific method for adjusting the temperature of the print head to each of a plurality of different temperatures. For example, it is conceivable to provide a heater for adjusting the temperature of the print head, but in this case, the configuration of the apparatus becomes complicated by the amount of the heater provided. Further, for example, it is conceivable to increase the temperature of the recording head by driving the recording head to eject ink, but in this case the ink is wasted. It is also conceivable to increase the temperature of the print head by driving the print head to such an extent that ink is not ejected. The temperature of the recording head does not rise easily.

An object of the present invention is to efficiently change the temperature of the liquid ejection head when printing a pattern for adjusting the landing position of the liquid in the scanning direction without complicating the configuration of the apparatus. Another object of the present invention is to provide a liquid ejecting apparatus capable of suppressing consumption of a large amount of liquid.

A liquid ejection apparatus according to the present invention includes a liquid ejection head having a plurality of nozzles, a carriage on which the liquid ejection head is mounted and which moves in a scanning direction, and a control device, wherein the control device moves the carriage as described above. An operation of driving the liquid ejection head to eject liquid from the plurality of nozzles onto a recording medium while moving in the scanning direction, wherein a first pattern for adjusting the landing position of the liquid in the scanning direction is selected. A first pattern recording operation for recording on a recording medium is performed a plurality of times by the liquid ejection head, and after each first pattern recording operation is performed by the liquid ejection head, the next first pattern recording operation is performed by the liquid ejection head. An operation of causing the liquid ejection head to eject liquid from the plurality of nozzles onto a recording medium while moving the carriage in the scanning direction before causing the ejection head to perform the operation, the landing position of the liquid in the scanning direction. a second pattern recording operation for recording a second pattern on a recording medium for adjustment other than The temperatures of the liquid ejection heads are made different from each other when the liquid ejection heads are caused to perform the recording operation.

In the present invention, after causing the liquid ejection head to perform each first pattern printing operation, and before causing the liquid ejection head to perform the next first pattern printing operation, the liquid ejection head is caused to perform the second pattern printing operation. Increase the temperature of the liquid ejection head. As a result, the temperatures of the liquid ejection heads are made different from each other when the liquid ejection heads are caused to perform the first pattern printing operation a plurality of times. In this case, when the liquid ejection head is driven to raise the temperature of the liquid ejection head, the second pattern is printed by the liquid ejected from the nozzles. Liquid is not wasted compared to the case where the liquid ejection head is driven to eject the liquid from the nozzles. Moreover, the temperature of the liquid ejection head can be efficiently raised compared to the case where the liquid ejection head is driven to such an extent that the liquid is not ejected from the nozzles in order to raise the temperature of the liquid ejection head.

1 is a schematic configuration diagram of a printer according to an embodiment of the present invention; FIG. 3 is a schematic configuration diagram of a recording unit and a feeding unit when viewed from the left side in the scanning direction; FIG. FIG. 3 is a plan view of FIG. 2 viewed from the direction of arrow III; 2 is a block diagram showing the electrical configuration of the printer; FIG. 4 is a flowchart showing the flow of processing when recording an image; (a) is a diagram for explaining an ejection timing adjustment pattern, and (b) is a diagram for explaining a transport amount adjustment pattern. 4 is a flowchart showing the flow of processing when recording a test pattern; FIG. 8 is a flowchart showing the flow of pattern recording processing in FIG. 7; FIG. 9A is a flow chart showing the flow of the conveyance amount adjustment pattern printing process in FIG. 8, and FIG. 9B is a flow chart showing the flow of the ejection timing adjustment pattern printing process in FIG. 7A and 7B are diagrams for explaining printing in the conveyance amount adjustment pattern printing process and the ejection timing adjustment pattern printing process when the variable N has each value; FIG. (a) is a diagram for explaining a pattern to be recorded on one side of a recording sheet, and (b) is a diagram for explaining a pattern to be recorded on the other side of the recording sheet. (a) is a diagram for explaining the relationship between the head temperature and the adjustment amount of the ejection timing, and (b) is a diagram for explaining the relationship between the conveyance direction position of the recording paper and the adjustment amount of the conveyance amount. be. 9 is a flowchart showing the flow of pattern recording processing according to modification 1; FIG. 11 is a block diagram showing an electrical configuration of a printer of Modification 2; 10 is a flowchart showing the flow of pattern recording processing according to modification 2; 11 is a flow chart showing the flow of pattern recording processing according to Modification 3. FIG. 14 is a flow chart showing the flow of pattern recording processing according to Modification 4. FIG. FIG. 12 is a diagram for explaining a pattern recorded on recording paper P in modification 4;

Preferred embodiments of the present invention are described below.

<Overall configuration of the printer>
The printer 1 (“liquid ejection device” of the present invention) according to the present embodiment is capable of not only recording an image on a recording sheet P (“recording medium” of the present invention), but also reading an image. , is a so-called compound machine. As shown in FIG. 1, the printer 1 includes a recording section 2 (see FIG. 2), a feeding section 3, a paper discharging section 4, a reading section 5, a display section 6, an operating section 7, and the like. Further, the operation of the printer 1 is controlled by a control device 50 (see FIG. 4).

The recording unit 2 is provided inside the printer 1 and performs recording on the recording paper P. As shown in FIG. The feeding section 3 is a section for feeding the recording paper P to the recording section 2 . The recording section 2 and the feeding section 3 will be described later in detail. The paper ejection section 4 is a section from which the recording paper P printed by the recording section 2 is ejected. The reading unit 5 is a scanner or the like, and reads an original. The display unit 6 is a liquid crystal display or the like, and displays necessary information and the like when the printer 1 is used. The operation unit 7 includes buttons provided on the housing of the printer 1, a touch panel provided on the display unit 6, and the like. can be entered.

<Feeding unit>
As shown in FIG. 2 , the feeding section 3 includes a cassette mounting section 11 , paper feeding rollers 12 , and a paper feeding path 13 . A paper cassette 14 is detachably attached to the cassette attachment portion 11 . The paper cassette 14 accommodates a plurality of recording papers P stacked vertically.

The paper feed roller 12 is provided in the cassette mounting portion 11 . The paper feed roller 12 is in contact with the uppermost sheet of the recording paper P among the plurality of recording papers P contained in the paper cassette 14 mounted in the cassette mounting portion 11 . The paper feed roller 12 is connected to a paper feed motor 56 (see FIG. 4) via gears (not shown). When the paper feed motor 56 is driven, the paper feed roller 12 rotates, and one sheet of recording paper P in contact with the paper feed roller 12 is sent out toward the paper feed path 13 . As a result, the recording paper P is conveyed along the paper feed path 13 . The paper feed path 13 will be described later.

<Recording section>
As shown in FIGS. 2 and 3, the recording unit 2 includes a carriage 21, an inkjet head 22 (the "liquid ejection head" of the present invention), a platen 23, transport roller pairs 24 and 25, and a switchback roller pair. 26 and a return roller pair 27 .

The carriage 21 is supported by two guide rails 31 and 32 extending in the scanning direction, and is movable in the scanning direction along the guide rails 31 and 32 . The carriage 21 is connected to a carriage motor 57 via a belt (not shown) or the like, and when the carriage motor 57 is driven, the carriage 21 moves in the scanning direction. In the following description, right and left sides in the scanning direction are defined as shown in FIGS. 1 and 3. FIG.

The inkjet head 22 is mounted on the carriage 21 . The inkjet head 22 ejects ink from a plurality of nozzles 20 formed on its lower surface. More specifically, the plurality of nozzles 20 are arranged in the transport direction perpendicular to the scanning direction to form a nozzle row 19 having a length L in the transport direction. are arranged in the scanning direction. Black, yellow, cyan, and magenta inks are ejected from the plurality of nozzles 20, respectively, from the nozzle row 19 on the right side in the scanning direction.

A platen 23 is arranged below the inkjet head 22 . The platen 23 extends over the entire length of the recording paper P in the scanning direction and supports the recording paper P from below.

The transport roller pair 24 (“upstream transport roller pair” of the present invention) is arranged upstream of the inkjet head 22 and the platen 23 in the transport direction. The transport roller pair 24 includes a driving roller 24a and a driven roller 24b. The driving roller 24a is connected to a conveying motor 58 via a gear (not shown) or the like. The driven roller 24b is arranged above the driving roller 24a, and can hold the recording paper P sandwiched from above and below by the driving roller 24a and the driven roller 24b. When the transport motor 58 is driven, the driving roller 24a rotates and the driven roller 24b rotates. As a result, the recording paper P held by the driving roller 24a and the driven roller 24b is conveyed in the conveying direction.

Further, the above-described paper feed path 13 is arranged between the cassette mounting portion 11 and the pair of transport rollers 24, and the recording paper P sent out from the paper feed cassette 14 by the paper feed roller 12 is guided by the arrow A1 in FIG. , the sheet is supplied to the pair of conveying rollers 24 along the sheet feeding path 13 from the upstream side in the conveying direction.

The transport roller pair 25 (“downstream transport roller pair” of the present invention) is arranged downstream of the inkjet head 22 and the platen 23 in the transport direction. The conveying roller pair 25 includes a driving roller 25a and a driven roller 25b. The driving roller 25a is connected to a conveying motor 58 via gears (not shown). The driven roller 25b is arranged above the drive roller 25a, and can hold the recording paper P sandwiched from above and below by the drive roller 25a and the driven roller 25b. When the transport motor 58 is driven, the drive roller 25a rotates and the driven roller 25b rotates. As a result, the recording paper P held by the driving roller 25a and the driven roller 25b is conveyed in the conveying direction.

The switchback roller pair 26 is arranged downstream of the transport roller pair 25 in the transport direction. The switchback roller pair 26 includes a driving roller 26a and a driven roller 26b. The driving roller 26a is connected to a conveying motor 58 via a gear (not shown) or the like. The driven roller 26b is arranged above the drive roller 26a, and can hold the recording paper P sandwiched from above and below by the drive roller 26a and the driven roller 26b. When the transport motor 58 is driven, the driving roller 26a rotates and the driven roller 26b rotates.

When the recording paper P is conveyed in the conveying direction by the pair of conveying rollers 24 and 25, the switchback roller pair 26, together with the pair of conveying rollers 24 and 25, is a recording medium held by the driving roller 26a and the driven roller 26b. The paper P is transported in the transport direction. As a result, the recording paper P can be transported to the paper discharge section 4 .

In addition, in a state where the trailing edge of the recording paper P (the upstream end in the transport direction) is positioned between the transport roller pair 25 and the switchback roller pair 26 in the transport direction, the transport motor 58 is turned on. When the recording paper P is conveyed in the conveying direction by 24 and 25 and is rotated in the opposite direction, the switchback roller pair 26 rotates the recording paper P held by the driving roller 26a and the driven roller 26b in the opposite direction as described above. direction. Thereby, the recording paper P can be sent to the switchback path 28 arranged below the platen 23 .

A return roller pair 27 is provided on a switchback path 28 . The return roller pair 27 includes a driving roller 27a and a driven roller 27b. The driving roller 27a is connected to a conveying motor 58 via gears (not shown). The driven roller 27b is arranged above the driving roller 27a, and can hold the recording paper P sandwiched from above and below by the driving roller 27a and the driven roller 27b. When the transport motor 58 is driven, the driving roller 27a rotates and the driven roller 27b rotates.

The transport motor 58 rotates in a direction opposite to the direction in which the recording paper P is transported by the transport roller pairs 24 and 25, and the switchback roller pair 26 moves the recording paper P through the switchback path as described above. 28, the return roller pair 27 transports the recording paper P toward the upstream side in the transport direction.

The recording paper P conveyed along the switchback path 28 is sent to the middle portion of the paper feed path 13 as indicated by the arrow A2 in FIG. It is sent to roller pair 24 . That is, the recording paper P sent to the switchback path 28 by the switchback roller pair 26 and conveyed by the return roller pair 27 is returned to the upstream side of the conveying roller pair 24 in the conveying direction while being turned over. In this embodiment, the combination of the switchback roller pair 26, the return roller pair 27, and the switchback path 28 corresponds to the "switchback mechanism" of the present invention.

<Electrical Configuration of Printer>
Next, the electrical configuration of the printer 1 will be described. As described above, the operation of printer 1 is controlled by control device 50 . As shown in FIG. 4, the control device 50 includes a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM (Random Access Memory) 53, a flash memory 54 (the "storage unit" of the present invention), an ASIC (Application Specific Integrated Circuit) 55 and the like, which control the operations of the paper feeding motor 56, carriage motor 57, inkjet head 22, conveying motor 58, reading section 5, display section 6, and the like. Also, a signal corresponding to the operation result of the operation unit 7 by the user is input to the control device 50 . In addition to the configuration described above, the printer 1 also includes a thermistor 59 (a "head temperature detector" of the present invention). The thermistor 59 is provided in the inkjet head 22 . A signal corresponding to the temperature of the inkjet head 22 is input to the controller 50 from the thermistor 59 .

In the control device 50, only the CPU 51 may perform various processes, only the ASIC 55 may perform various processes, or the CPU 51 and the ASIC 55 may cooperate to perform various processes. can be anything. Further, the control device 50 may be one in which one CPU 51 performs processing alone, or may be one in which a plurality of CPUs 51 share the processing. Further, the control device 50 may be one in which one ASIC 55 performs processing alone, or may be one in which a plurality of ASICs 55 share the processing.

<Control during recording>
Next, the flow of processing by the control device 50 when recording an image on the recording paper P in the recording section 2 will be described.

When recording an image on the recording paper P in the recording unit 2, the control device 50 performs processing according to the flow of FIG. The flow of FIG. 5 is started when a print command instructing the printer 1 to print an image is input. At this time, along with a recording command, the printer 1 is also supplied with image data of an image to be recorded, a single-sided recording mode for recording only on one side of the recording paper P, and a recording mode for recording on both sides of the recording paper P. A signal or the like indicating in which recording mode of the two-sided recording mode the recording is to be performed is input.

Referring to the flow of FIG. 5, the control device 50 first executes paper feeding processing (S101). In the paper feed process of S101, the controller 50 drives the paper feed motor 56 to convey one sheet of recording paper P contained in the paper cassette 14 along the paper feed path 13 to the paper feed roller 12. and supplies it to the conveying roller pair 24 . Further, the conveying motor 58 is driven to transfer the recording paper P to the conveying roller pair 24 at a position where the inkjet head 22 and the most downstream portion in the conveying direction of the area where the image of the recording paper P is recorded face each other. be transported to

Subsequently, the controller 50 obtains the temperature of the inkjet head 22 (hereinafter sometimes referred to as "head temperature Th") based on the signal from the thermistor 59 (S102). Then, based on the acquired head temperature Th and the adjustment information stored in advance in the flash memory 54, the amount of adjustment for the ink ejection timing from the nozzles 20 in the scanning process of S104 described below is determined (S103 ). The determination of the adjustment information and the ejection timing adjustment amount will be described later in detail.

Subsequently, the control device 50 executes scanning processing (S104). In the scanning process of S<b>104 , the control device 50 drives the carriage motor 57 to move the carriage 21 in the scanning direction, and drives the inkjet head 22 to eject ink from the plurality of nozzles 20 . to record part of the image. At this time, the ink is ejected from the nozzles 20 at the ejection timing adjusted according to the ejection timing adjustment amount determined in S103.

Then, if the recording of the image on the recording paper P is not completed (S105: NO), then the control device 50 executes the conveying process (S106), and then returns to the scanning process of S104. In the transport process of S106, the control device 50 drives the transport motor 58 to cause the pair of transport rollers 24 and 25 to transport the recording paper P by a predetermined distance (for example, length L).

Thus, in this embodiment, the scanning process and the transporting process are repeated until the image recording on the recording paper P is completed. Further, at this time, the scanning process is executed a plurality of times. In these scanning processes, the carriage 21 is moved to the right in the scanning direction, and the ink is ejected from the nozzles 20. The operation of ejecting ink from a plurality of nozzles 20 while moving to the left in the scanning direction is alternately performed.

Then, when the recording of the image on the recording paper P is completed (S105: YES), if there is no image data to be recorded on the next page (S107: NO), the control device 50 performs the paper ejection process. is executed (S108), and the process ends. In the paper discharge process of S<b>108 , the control device 50 drives the transport motor 58 to transport the recording paper P to the paper discharge unit 4 by the transport roller pairs 24 and 25 and the switchback roller pair 26 .

If image data to be recorded on the next page remains (S107: YES) and the double-sided recording mode is set (S109: YES), the control device 50 executes switchback processing. (S110) and returns to S104. In the switchback process of S110, the control device 50 drives the transport motor 58 to supply the recording paper P to the transport roller pair 24 while turning the recording paper P over the switchback roller pair 26 and the return roller pair 27 as described above. . Further, as in S101, the conveying motor 58 is driven to move the recording paper P to the conveying roller pair 24 with the most downstream portion in the conveying direction of the area where the ink jet head 22 and the image of the recording paper P are recorded. are transported to a position facing each other.

On the other hand, if image data to be recorded on the next page remains (S107: YES) and if the single-sided recording mode is selected (S109: NO), the control device 50 performs the same ejection process as in S108. Paper processing is executed (S111), and the process returns to S101.

<Control during test pattern recording>
Next, the flow of processing by the control device 50 when recording a test pattern in the recording section 2 will be described. In this embodiment, as the test pattern, a plurality of ejection timing adjustment patterns 70 (“first pattern” of the present invention) for adjusting ejection timings (ink landing positions in the scanning direction) from the nozzles in the scanning process of S104 are used. ), and a plurality of transport amount adjustment patterns 80 for adjusting the transport amount of the recording paper P (ink landing positions in the transport direction) by the pair of transport rollers 24 and 25 .

Here, as shown in FIG. 6A, the ejection timing adjustment pattern 70 has two pattern portions 71 and 72 . The pattern portion 71 is a straight line parallel to the transport direction. The pattern portion 72 is a straight line that is inclined with respect to the transport direction and intersects the pattern portion 71 . The relationship between the ejection timing adjustment pattern 70 and the ejection timing adjustment amount will be described later.

Also, as shown in FIG. 6B, the transport amount adjustment pattern 80 has two pattern portions 81 and 82 . The pattern portion 81 is a straight line parallel to the scanning direction. The pattern portion 82 is a straight line inclined with respect to the scanning direction and intersects the pattern portion 81 . The relationship between the transport amount adjustment pattern 80 and the transport amount adjustment amount will be described later.

When recording a test pattern in the recording unit 2, the control device 50 performs processing according to the flow of FIG. More specifically, the control device 50 first executes a pattern recording process (S201). In the pattern recording process of S201, as shown in FIG. 8, the control device 50 first executes the paper feed process similar to that of S101 (S301). Subsequently, the control device 50 resets the variable N to 0 (S302) and resets the variable m to 1 (S303). Here, the variable N corresponds to the number of times the recording paper P is conveyed in steps S406 and S504, which will be described later. Also, the variable m corresponds to the number of the ejection timing adjustment pattern recording process among the ejection timing adjustment pattern recording processes that are performed a plurality of times, as will be described later.

Subsequently, when the variable N is not _Nm (S304: NO), the control device 50 executes the transport amount adjustment pattern recording process (S305). Here, N _m corresponds to the number of times the recording paper P is conveyed in S406 or S504 described later until the m-th ejection timing adjustment pattern recording process is executed, and is stored in the flash memory 54 in advance. It is N _m is a state in which the recording paper P is held by both the transport roller pair 24 and the transport roller pair 25 when the recording paper P is conveyed N _m times in S406 or S504, which will be described later. is set to a value similar to

In _the transport amount adjustment pattern recording process of S305, as shown in FIG. drives the carriage motor 57 to move the carriage 21 to the left in the scanning direction, and drives the inkjet head 22 to move the nozzles on the upstream side in the transport direction out of the plurality of nozzles 20 forming the nozzle row 19. Ink is discharged from 20 to record a pattern portion 81 as shown in FIG. 10 (S402). However, in the determination of S401, when m=1, N _(m−1) (=N ₀ ) is set to 0 for determination.

Here, in FIG. 10, the inkjet head 22 (plurality of nozzles 20) is illustrated on the left side because when the value of the variable N is each value, the length of the recording paper P in the transport direction is L indicates that the region R of is opposed to a plurality of nozzles 20 and that printing can be performed in the region R. FIG. Also, in FIG. 10, the portions recorded when the value of N is at each value are illustrated by solid lines, and the portions recorded so far are illustrated by dashed lines.

When the variable N is [N _m -1] (S401: NO, S403: YES), the controller 50 drives the carriage motor 57 to move the carriage 21 to the left in the scanning direction, The inkjet head 22 is driven to eject ink from the nozzles 20 on the downstream side in the transport direction among the plurality of nozzles 20 forming the nozzle row 19, thereby recording a pattern portion 82 as shown in FIG.

If the variable N is neither [N _(m-1) +1] nor [N _m -1] (S401: NO, S403: NO), the controller 50 drives the carriage motor 57 to While moving the carriage 21 to the left in the scanning direction, the inkjet head 22 is driven to eject ink from the nozzles 20 on the upstream side in the transport direction among the plurality of nozzles 20 forming the nozzle row 19 , thereby forming the pattern portion 81 . is recorded, and the pattern portion 82 is recorded by ejecting ink from the nozzles 20 on the downstream side in the transport direction.

Here, in S402, S404, and S405, the carriage 21 is moved leftward in the scanning direction, but this is not restrictive. In any of S402, S404, and S405, the carriage 21 may be moved to the right in the scanning direction. That is, the moving direction of the carriage 21 should be the same between S402, S404, and S405.

After completion of any one of S402, S404, and S405, the control device 50 drives the transport motor 58 to move the recording paper P between the transport roller pairs 24 and 25 to half the length L of the nozzle row 19. (L/2) (S406), the variable N is incremented by 1 (S407), and the flow returns to FIG.

Returning to the flow of FIG. 8, when the variable N is _Nm (S304: YES), the control device 50 executes the non-ejection driving process (S306). In the non-ejection driving process of S<b>306 , the control device 50 causes the inkjet head 22 to perform non-ejection driving in which the ink is not ejected from the nozzles 20 .

Subsequently, the control device 50 executes ejection timing adjustment pattern recording processing (S307). In the ejection timing adjustment pattern recording process of S307, as shown in FIG. 9B, the control device 50 first acquires the head temperature Th similarly to S102 and stores it in the RAM 53 or the like (S501).

Subsequently, the controller 50 drives the carriage motor 57 to move the carriage 21 to the left in the scanning direction, and drives the inkjet head 22 to eject ink from the plurality of nozzles 20, thereby moving the carriage 21 to the left in the scanning direction. A plurality of arranged pattern portions 71 are recorded (S502). Subsequently, the control device 50 drives the carriage motor 57 to move the carriage 21 to the right in the scanning direction, and drives the inkjet head 22 to eject ink from the plurality of nozzles 20, thereby forming a plurality of patterns. A plurality of pattern portions 72 corresponding to the portion 71 are recorded (S503). Thereby, as shown in FIG. 10, a plurality of ejection timing adjustment patterns 70 arranged in the scanning direction are recorded on the recording paper P. FIG.

Subsequently, the control device 50 drives the conveying motor 58 to cause the pair of conveying rollers 24 and 25 to convey the recording paper P by half the length (L/2) of the length L of the nozzle row 19 (S504). , variable N and variable m are incremented by 1 (S505), and the flow returns to FIG.

Returning to the flow of FIG. 8, after either the conveyance amount adjustment pattern recording process of S305 or the ejection timing adjustment pattern recording process of S307 is executed, recording on the surface of the recording paper P currently serving as the top surface is performed. is not completed (S308: NO), the process returns to S304. Further, when the recording on the surface of the recording paper P which is currently the upper surface is completed (S308: YES), one surface P1 of the recording paper P (the surface which is the upper surface in the state before switchback) (S309: YES), the control device 50 executes the same switchback process as in S111 (S310), and then returns to S304. Further, when recording is being performed on the other surface P2 of the recording paper P (the surface that becomes the top surface after being switched back) (S309: NO), the control device 50 performs the same operation as in S106. After executing the paper ejection process (S311), the process returns to the flow of FIG.

In the pattern recording process of S201, when the ejection timing adjustment pattern 70 and the transport amount adjustment pattern 80 are recorded as described above, on one surface P1 and the other surface P2 of the recording paper P, the patterns shown in FIG. , (b), pattern rows 75 in which a plurality of ejection timing adjustment patterns 70 are arranged in the scanning direction are arranged in multiple rows (three rows in FIG. 11A, three rows in FIG. 11 ( In b), they line up in two rows). Pattern rows 85 in which a plurality of transport amount adjustment patterns 80 are arranged in the scanning direction are arranged in a plurality of rows in the transport direction on both sides of each pattern row 75 in the transport direction.

In this embodiment, the process of S502 causes the inkjet head 22 to print a plurality of pattern portions 71 corresponding to each pattern row 75, and the process of S503 causes the inkjet head 22 to print a plurality of patterns corresponding to the pattern row 75. The combination of the operation of recording the portion 72 corresponds to the "first pattern recording operation" of the present invention.

Further, in the present embodiment, among the plurality of pattern rows 85, the pattern row positioned upstream in the transport direction from the most upstream pattern row 75 printed on the other surface P2 of the recording paper P in the transport direction. The transport amount adjustment patterns 80 forming the pattern row 85 excluding the pattern 85 correspond to the "second pattern" of the present invention. Then, the process of S402 or S405 causes the inkjet head 22 to record a plurality of pattern portions 81 corresponding to the pattern row 85 to be the second pattern, and the process of S404 or S405 causes the inkjet head 22 to record the plurality of pattern portions 82. corresponds to the "second pattern recording operation" of the present invention.

Returning to the flow of FIG. 7, after the pattern recording process of S201 is completed, the control device 50 causes the display unit 6 to display a message prompting the user to read the plurality of recorded patterns 70 and 80 (S202). ). This message is, for example, a message prompting the user to set the recording paper P on which a plurality of patterns 70 and 80 are recorded in the reading section 5, and then operate the operation section 7 to input a reading instruction signal. be.

Then, the control device 50 waits until a reading instruction signal is input (S203: NO), and when the reading instruction signal is input (S203: YES), executes pattern reading processing (S204). In the pattern reading process of S204, the control device 50 causes the reading section 5 to read the plurality of recorded patterns 70 and 80. FIG.

Subsequently, the control device 50 determines adjustment information based on the reading results of the plurality of patterns 70 and 80 in the pattern reading process of S204, and executes an adjustment information storage process of storing it in the flash memory 54 (S205). .

In the adjustment information storage process of S205, the control device 50 stores, for each pattern row 75, the average value of the positions in the transport direction of the intersections of the pattern portions 71 and the pattern portions 72 in the plurality of ejection timing adjustment patterns 70, and the pattern row Based on the head temperature Th during printing of the plurality of ejection timing adjustment patterns 70 constituting 75, the head temperature Th as shown in FIG. is obtained, and the adjustment information is stored in the flash memory 54 . In this embodiment, it is assumed that the distances between the plurality of nozzles 20 and the recording paper P are substantially constant regardless of the position of the carriage 21 in the scanning direction. The adjustment information is acquired using the average value of the positions of the intersections of the pattern portions 71 and 72 in the transport direction.

Here, in this embodiment, when the temperature of the inkjet head 22 is a predetermined reference temperature and the distance between the plurality of nozzles 20 and the recording paper P is a predetermined reference distance, the solid line in FIG. , the pattern portions 71 and 72 are recorded by ejecting ink from the nozzles 20 at such timing that the midpoint of the pattern portion 71 and the midpoint of the pattern portion 72 overlap.

Therefore, when the temperature of the inkjet head 22 is the above reference temperature and the distance between the plurality of nozzles 20 and the recording paper P is greater than the above reference distance, the pattern portion 71 is less likely to be formed than when the reference distance is used. The printed position shifts to the left in the scanning direction, and the printed position of the pattern portion 72 shifts to the right in the scanning direction. As a result, as indicated by broken lines in FIG. 6A, the pattern portion 72 shifts to the right in the scanning direction with respect to the pattern portion 71, and the intersection of the pattern portions 71 and 72 is located downstream in the transport direction. shift to

On the other hand, when the temperature of the inkjet head 22 is the above reference temperature and the distance between the plurality of nozzles 20 and the recording paper P is smaller than the above reference distance, the pattern portion 71 is less dense than when the reference distance is used. The printed position shifts to the right in the scanning direction, and the printed position of the pattern portion 72 shifts to the left in the scanning direction. As a result, as indicated by the dashed line in FIG. 6A, the pattern portion 72 shifts to the left in the scanning direction with respect to the pattern portion 71, and the intersection of the pattern portion 71 and the pattern portion 72 is located upstream in the transport direction. shift to the side.

For these reasons, when the position of the intersection between the pattern portion 71 and the pattern portion 72 is located downstream of the midpoint of the pattern portion 71 in the conveying direction, the position of this intersection is away from the pattern portion 71. The adjustment amount of the ejection timing shown in FIG. 12A indicates that the ejection timing is advanced as the case increases. Further, when the position of the intersection of the pattern portion 71 and the pattern portion 72 is positioned upstream in the transport direction from the midpoint of the pattern portion 71, the farther the position of the intersection is from the pattern portion 71, the more It is assumed that the ejection timing adjustment amount shown in FIG. 12A indicates that the ejection timing is delayed.

In FIG. 12A, the fact that the adjustment amount is 0 means that the ejection timing is the same timing (reference timing) as when the ejection timing adjustment pattern 70 is printed. Further, the fact that the adjustment amount is greater than 0 means that the larger the absolute value is, the more the ejection timing is delayed from the reference timing. Further, the fact that the adjustment amount is smaller than 0 means that the greater the absolute value, the earlier the ejection timing than the reference timing.

In addition, in the adjustment information storage processing of S205, for each pattern row 85, the average value of the positions in the scanning direction of the intersections of the pattern portions 81 and the pattern portions 82 in the plurality of transport amount adjustment patterns 80, and the pattern row Based on the position of the recording paper P in the transport direction when the transport amount adjustment pattern 80 constituting 85 is printed, the position of the recording paper P in the transport direction as shown in FIG. Information indicating the relationship between the adjustment amount of the conveying amount of the recording paper P in the process is acquired, and this information is stored in the flash memory 54 .

Here, in the present embodiment, in the transport amount adjustment pattern 80, the pattern portion 81 and the pattern portion 82 intersect with which portion of the pattern portion 81 so that the pattern portion 82 overlaps depends on whether the pattern portion 81 or the pattern portion 82 It is determined by the transport amount of P. On the other hand, in the present embodiment, when the transport amount of the recording paper P in S406 is the predetermined reference transport amount, the pattern portion 82 becomes the pattern portion 82 as indicated by the solid line in FIG. The pattern portions 81 and 82 are printed by ejecting ink from the nozzles 20 at such timings as to overlap with the midpoint of the pattern 81 .

Therefore, when the transport amount of the recording paper P in S406 is larger than the reference transport amount, the position where the pattern portion 82 is printed shifts to the upstream side in the transport direction compared to the case of the reference transport amount. . As a result, as indicated by the dashed line in FIG. 6B, the intersection of the pattern portion 81 and the pattern portion 82 shifts to the right in the scanning direction.

On the other hand, when the transport amount of the recording paper P in S406 is smaller than the reference transport amount, the printed position of the pattern portion 82 is shifted downstream in the transport direction compared to the case of the reference transport amount. . As a result, as indicated by the dashed line in FIG. 6B, the intersection of the pattern portions 81 and 82 shifts to the left in the scanning direction.

For these reasons, when the position of the intersection between the pattern portion 81 and the pattern portion 82 is located on the right side of the scanning direction from the midpoint of the pattern portion 81, when the position of the intersection is away from the pattern portion 81 It is assumed that the adjustment amount of the transport amount shown in FIG. In addition, when the position of the intersection of the pattern portion 81 and the pattern portion 82 is positioned to the left of the midpoint of the pattern portion 81 in the scanning direction, the farther the position of the intersection is from the pattern portion 81, the better. The adjustment amount of the transport amount indicated by 12(b) indicates that the transport amount is increased.

In FIG. 12B, the adjustment amount of 0 means that the transport amount is the same as the reference transport amount, and the adjustment amount greater than 0 indicates that the greater the absolute value, the greater the transport. When the adjustment amount is smaller than 0, the greater the absolute value, the smaller the transport amount.

<effect>
Here, the higher the head temperature Th, the lower the viscosity of the ink in the inkjet head 22 and the faster the ejection speed of the ink when the inkjet head 22 ejects the ink from the nozzles 20 . Therefore, the landing position of the ink ejected from the nozzles 20 on the recording paper P in the scanning direction changes depending on the head temperature Th. Therefore, it is preferable that the timing of ejecting ink from the nozzles 20 when recording an image is varied according to the head temperature Th.

Therefore, in the present embodiment, after the plurality of ejection timing adjustment patterns 70 forming each pattern row 75 are printed on the inkjet head 22, the plurality of ejection timing adjustment patterns 70 forming the pattern row 75 are printed by the inkjet head 22. A plurality of transport amount adjustment patterns 80 are recorded by the inkjet head 22 before being recorded by the inkjet head 22 . When the inkjet head 22 is caused to record a plurality of transport amount adjustment patterns 80, the temperature of the inkjet head 22 rises. As a result, the head temperature Th when the plurality of ejection timing adjustment patterns 70 are recorded by the inkjet head 22 can be made different between the plurality of pattern rows 75 . Thereby, as described above, it is possible to obtain the relationship between the head temperature Th and the adjustment amount of the ejection timing.

In this case, the inkjet head 22 is driven to eject ink from the nozzles 20 , thereby recording a plurality of transport amount adjustment patterns 80 and raising the temperature of the inkjet head 22 . Therefore, compared to the case where the ink jet head 22 is driven to eject ink from the nozzles 20 for flushing only to increase the temperature of the ink jet head 22, the amount of wasted ink can be reduced. . In addition, the temperature of the inkjet head 22 can be efficiently raised as compared with the case where only non-ejection driving is performed to drive the inkjet head 22 to such an extent that ink is not ejected from the nozzles 20 in order to raise the temperature of the inkjet head 22. be able to.

Then, in the present embodiment, as described above, the reading unit 5 is caused to read the recorded ejection timing adjustment pattern 70 . Then, the reading results of the plurality of ejection timing adjustment patterns 70 forming each pattern row 75 (the position of the intersection of the pattern portion 71 and the pattern portion 72 in the transport direction) and the plurality of ejection timing adjustment patterns forming each pattern row 75 are read. Adjustment information indicating the relationship between the head temperature Th and the ejection timing adjustment amount is acquired based on the head temperature Th during printing in 70 and stored in the flash memory 54 . Then, when recording an image, ink is ejected from the nozzles 20 at a timing corresponding to the adjustment information stored in the flash memory 54 . This makes it possible to appropriately adjust the ink landing position in the scanning direction during image printing.

Further, as described above, the landing position of the ink ejected from the nozzles 20 on the recording paper P in the scanning direction changes depending on the head temperature Th. In addition, in the ejection timing adjustment pattern 70, the moving direction of the carriage 21 is opposite when printing the pattern portion 71 and when printing the pattern portion 72. The direction of deviation of the landing position due to the change in Th is reversed. Therefore, how much the intersection of the pattern portion 71 and the pattern portion 72 shifts from the midpoint of the pattern portion 71 in the transport direction depends on the head temperature Th.

On the other hand, in the transport amount adjustment pattern 80 , the moving direction of the carriage 21 is the same when printing the pattern portion 81 and when printing the pattern portion 82 . , the direction of deviation of the landing position due to the change in the head temperature Th is the same. Therefore, how much the intersection of the pattern portion 81 and the pattern portion 82 deviates from the midpoint of the pattern portion 81 in the scanning direction hardly changes depending on the head temperature Th.

That is, the transport amount adjustment pattern 80 is less affected by the head temperature Th than the ejection timing adjustment pattern 70 . Therefore, it is effective to employ the transport amount adjustment pattern 80 as a test pattern to be printed in order to raise the temperature of the inkjet head 22 as in this embodiment.

Further, in this embodiment, when the recording paper P is conveyed by the conveying roller pair 24 and 25 in the recording unit 2, the recording paper P is first held only by the conveying roller pair 24, and then is held by the conveying roller pair. The sheet is held by both the pairs 24 and 25, and then held by the conveying roller pair 24 only. On the other hand, when the recording paper P is held by both of the pair of transport rollers 24 and 25, the posture of the recording paper P is more stable than when it is held by only one of the pair of transport rollers 24 and 25. FIG.

Therefore, in the present embodiment, the ejection timing adjustment pattern 70 is printed in a state in which the recording paper P is held by both the transport roller pairs 24 and 25 and is in a stable posture. Accordingly, it is possible to accurately adjust the ink landing position in the scanning direction based on the printing result of the ejection timing adjustment pattern 70 .

However, the area of the recording paper P in which recording can be performed while being held by both the conveying roller pairs 24 and 25 (the area facing the plurality of nozzles 20) is limited. Therefore, in the present embodiment, the ejection timing adjustment pattern 70 is recorded on one surface P1 and the other surface P2 of the recording paper P while the recording paper P is held by both the transport roller pairs 24 and 25. . As a result, the number of ejection timing adjustment patterns 70 that can be recorded on one sheet of recording paper P while being held by both the transport roller pairs 24 and 25 can be increased.

Further, in the present embodiment, the temperature of the inkjet head 22 is raised by causing the inkjet head 22 to perform non-ejection driving in addition to recording the plurality of transport amount adjustment patterns 80 on the inkjet head 22 . As a result, the temperature of the inkjet head 22 can be increased more than when the temperature is increased only by printing the plurality of transport amount adjustment patterns 80 .

Here, the transport amount adjustment pattern 80 is composed of linear pattern portions 81 and 82, and the amount of ink ejected from the nozzles 20 to record the transport amount adjustment pattern 80 is not so large. . Therefore, the temperature of the inkjet head 22 may not be sufficiently raised only by printing the transport amount adjustment pattern 80 . On the other hand, in order to accurately obtain the relationship between the head temperature Th and the ejection timing adjustment amount as shown in FIG. It is preferable that the difference in head temperature Th is large to some extent. Therefore, in the case of the present embodiment, the temperature of the inkjet head 22 is raised by causing the inkjet head 22 to perform non-ejection driving in addition to causing the inkjet head to print the transport amount adjustment pattern 80 . is valid.

[Modification]
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims.

For example, in the above-described embodiment, the temperature of the inkjet head 22 is raised by causing the inkjet head 22 to perform non-ejection driving in addition to causing the inkjet head 22 to print the transport amount adjustment pattern 80 . , but not limited to.

For example, in the modified example 1, in the pattern recording process, as shown in FIG. 13, when the variable N is _Nm (S304: YES), the control device 50 executes the flushing process (S601), An ejection timing adjustment pattern recording process is executed (S307).

In the flushing process of S601, the controller 50 drives the carriage motor 57 to move the carriage 21 to a position where the plurality of nozzles 20 face an ink receiver (not shown), and then drives the inkjet head 22 to The inkjet head 22 is caused to perform flushing for ejecting ink from the nozzles 20 toward the ink receiver. Note that the flow of other processes in the pattern recording process of Modification 1 is the same as that of the above-described embodiment.

In Modification 1 as well, the temperature of the inkjet head 22 is raised by causing the inkjet head 22 to perform flushing in addition to recording the plurality of transport amount adjustment patterns 80 on the inkjet head 22. can be increased more than when it is increased only by printing a plurality of transport amount adjustment patterns 80 .

Further, as in the above-described embodiment and modified example 1, in addition to constantly recording a plurality of transport amount adjustment patterns 80 on the inkjet head 22, by causing the inkjet head 22 to perform non-ejection driving or flushing, It is not limited to raising the temperature of the inkjet head 22 .

In Modified Example 2, as shown in FIG. 14, a printer 100 includes a temperature sensor 101 (an "environmental temperature acquisition unit" of the present invention) in addition to the same configuration as the printer 1 of the above-described embodiment. The temperature sensor 101 is for detecting the temperature in the vicinity of the inkjet head 22 (hereinafter sometimes referred to as "environmental temperature Te"), and a signal indicating the environmental temperature Te is sent from the temperature sensor 101 to the controller 50. is entered.

Then, in the second modification, in the test pattern recording process, as shown in FIG. 15, when the variable N is N _m (S304: YES), the control device 50, based on the signal from the temperature sensor 101, Information on the environmental temperature Te is acquired (S701). Then, if the ambient temperature Te is equal to or lower than the predetermined temperature Te1 (S702: YES), the non-ejection driving process is executed (S306), and then the ejection timing adjustment pattern recording process is executed as in the above-described embodiment. (S307). On the other hand, if the ambient temperature Te is higher than the predetermined temperature Te1 (S702: NO), the ejection timing adjustment pattern recording process is performed without executing the non-ejection driving process (S307).

A printer according to the third modification is similar to the printer 100 according to the second modification. In Modified Example 3, in the test pattern recording process, as shown in _FIG . Information on Te is acquired (S701). Then, if the environmental temperature Te is equal to or lower than the predetermined temperature Te1 (S702: YES), as in Modification 1, the flushing process is executed (S601), and then the ejection timing adjustment pattern recording process is executed (S307). . On the other hand, if the environmental temperature Te is higher than the predetermined temperature Te1 (S702: NO), the process proceeds directly to the ejection timing adjustment pattern recording process without executing the flushing process (S307).

Note that the flow of other processes in the pattern recording processes of Modifications 2 and 3 are the same as those of the above-described embodiment and Modification 1, respectively.

When the ambient temperature (environmental temperature Te) of the inkjet head 22 is low, the temperature of the inkjet head 22 is less likely to rise when the inkjet head 22 is driven. Therefore, in Modified Examples 2 and 3, when the ambient temperature Te is equal to or lower than the predetermined temperature Te1, the inkjet head 22 is caused to perform non-ejection driving or flushing in addition to the printing of the second pattern. Thereby, the temperature of the inkjet head 22 is increased. Thereby, the temperature of the inkjet head 22 can be efficiently raised.

On the other hand, when the temperature around the inkjet head 22 (environmental temperature Te) is high, the temperature of the inkjet head 22 tends to rise when the inkjet head 22 is driven. Therefore, in Modified Examples 2 and 3, when the environmental temperature Te is higher than the predetermined temperature Te1, the inkjet head 22 is caused to perform printing of the second pattern without causing the inkjet head 22 to perform non-ejection driving or flushing. only increases the temperature of the inkjet head 22 . This makes it possible to reduce power consumption and shorten the time required to record test patterns.

In addition, in the above-described embodiment and Modifications 1 to 3, in addition to causing the inkjet head 22 to perform printing of the second pattern, by causing the inkjet head 22 to perform only one of non-ejection driving and flushing, , the temperature of the inkjet head 22 is increased, but the present invention is not limited to this. In addition to causing the inkjet head 22 to print the second pattern, the temperature of the inkjet head 22 may be raised by causing the inkjet head 22 to perform both non-ejection driving and flushing.

In this case, the inkjet head 22 is not limited to performing both non-ejection driving and flushing. For example, when the environmental temperature Te is equal to or lower than the predetermined temperature Te1, the inkjet head 22 is caused to perform both non-ejection driving and flushing. The head 22 may be made to do so.

Furthermore, the temperature of the inkjet head 22 may be raised only by causing the inkjet head 22 to always record the transport amount adjustment pattern 80 .

In the above-described embodiment, the ejection timing adjustment patterns 70 are printed on both sides of the recording paper P in order to increase the number of ejection timing adjustment patterns 70 that can be printed on one sheet of recording paper P. Not limited. The ejection timing adjustment pattern 70 may be recorded only on one side of the recording paper P. In this case, the ejection timing adjustment pattern 70 may be printed only on one sheet of recording paper P, or the ejection timing adjustment pattern 70 may be printed on a plurality of sheets of recording paper P. FIG. If the ejection timing adjustment patterns 70 are printed over a plurality of recording papers P, even when the required number of ejection timing adjustment patterns 70 is large, the ejection timing can be determined while the recording paper P is held by both the conveying roller pairs 24 and 25 . An adjustment pattern 70 can be recorded.

Further, in the above-described embodiment, the discharge timing adjustment pattern 70 is recorded while the recording paper P is held by both the pair of transport rollers 24 and 25, but the invention is not limited to this. A plurality of ejection timing adjustment patterns 70 forming at least part of the pattern row 75 may be printed while the recording paper P is held by only one of the transport roller pair 24 and 25 .

Further, the printer may have a configuration in which the conveyed recording paper P is waved along the scanning direction, as described in Japanese Patent Laid-Open No. 2018-144142, for example. In this case, the distance between the plurality of nozzles 20 and the recording paper P varies greatly depending on the position of the carriage 21 in the scanning direction. Therefore, as in the above-described embodiment, a pattern row 75 in which a plurality of ejection timing adjustment patterns 70 are arranged in the scanning direction is formed. By adjusting the ejection timing at each position in the scanning direction based on the position of , the landing position of the recording paper P in the scanning direction can be adjusted appropriately.

On the other hand, when the distances between the plurality of nozzles 20 and the recording paper P can be considered to be substantially constant regardless of the position in the scanning direction, as in the above-described embodiment, the plurality of ejection timing adjustment patterns 70 are arranged in the scanning direction. Instead of printing the pattern row 75, only one ejection timing adjustment pattern 70 may be printed. In this case, the adjustment amount of the ejection timing can be appropriately determined based on the printing result of this one ejection timing adjustment pattern 70 .

Also, the ejection timing adjustment pattern and the transport amount adjustment pattern may be patterns different from those described above.

In the above description, the recorded pattern is read by the reading unit 5, and the adjustment information is acquired using the test pattern read result by the reading unit 5 and stored in the flash memory 54. However, the present invention is not limited to this. do not have.

For example, a plurality of ejection timing adjustment patterns 70 are printed by changing the ejection timing of the ink from the nozzles 20 when printing the pattern portions 71 and 72, and the user is instructed to select one of the printed ejection timing adjustment patterns. One ejection timing adjustment pattern 70 may be selected such that the intersection of the pattern portion 71 and the pattern portion 72 is closest to the midpoint of the pattern portion 71 . In this case, for example, by causing the user to operate the operation unit 7 to input a signal for selecting one ejection timing adjustment pattern 70, the adjustment information is acquired based on the input signal, Store in the flash memory 54 . Further, in this case, the printer does not have to be a multifunction machine having the reading unit 5, and may be one that only records images.

Also, the pattern to be recorded by the inkjet head 22 to raise the temperature of the inkjet head 22 is not limited to the transport amount adjustment pattern.

In Modified Example 4, the control device 50 performs processing along the flow of FIG. 17 in the pattern recording process. More specifically, the controller 50 first performs the paper feeding process (S801) similar to S101, and acquires the head temperature Th (S802). Subsequently, the control device 50 executes the same ejection timing adjustment pattern recording process as in S307 (S803).

Subsequently, the control device 50 executes the transport process (S804). In the conveying process of S804, the control device 50 drives the conveying motor 58 to cause the pair of conveying rollers 24 and 25 to convey the recording paper P by a distance longer than the length L of the nozzle row 19. FIG. In S804, S806, 809, and S811, which will be described later, the recording paper P is conveyed by a distance longer than the length L of the nozzle array 19 because the ejection timing adjustment pattern 70, the ejection amount adjustment pattern 110, and the density adjustment pattern 110, which will be described later. This is to provide a space from the unevenness adjustment pattern 120 .

Subsequently, the control device 50 executes the ejection amount adjustment pattern printing process (S805). In the ejection amount adjustment pattern printing process of S805, the control device 50 drives the carriage motor 57 to move the carriage 21 in the scanning direction, and drives the inkjet head 22 to eject ink from the plurality of nozzles 20. , the ink jet head 22 is caused to record an ejection amount adjustment pattern 110 (the "second pattern" of the present invention) as shown in FIG.

The ejection amount adjustment pattern 110 has four pattern portions 111 to 114 arranged adjacently in the scanning direction. The pattern portions 111 to 114 are all rectangular filled patterns, but the pattern portions located on the right side in the scanning direction (in the order of the pattern portions 111, 112, 113, and 114) have more nozzles 20 to be used for printing ( duty is high).

Here, when a plurality of inkjet heads 22 are manufactured, there is variation in the amount of ink ejected from the nozzles 20 when the plurality of inkjet heads 22 are driven in the same manner due to manufacturing errors. Therefore, if the inkjet head 22 is uniformly driven regardless of the printer, the density of the recorded image will be higher in the printer equipped with the inkjet head 22 having the larger ejection amount. Therefore, in Modified Example 4, the ejection amount adjustment pattern 110 is printed. If the ejection amount adjustment pattern 110 is read by the reading unit 5 and the density information of the pattern portions 111, 112, 113, and 114 is acquired, driving of the inkjet head 22 for each printer can be performed based on the acquired density information. You can adjust how it works.

Subsequently, the control device 50 executes the same conveying process as in S804 (S806), acquires the head temperature Th as in S802 (S807), and executes the ejection timing adjustment pattern printing process as in S803. (S808).

Subsequently, the control device 50 executes the same conveying process as in S804 and S806 (S809), and then prints the density unevenness adjustment pattern 120 (“second pattern” of the present invention) as shown in FIG. (S810). The density unevenness adjustment pattern 120 has two pattern portions 121 and 122 adjacent to each other in the transport direction. The pattern portion 121 and the pattern portion 122 are rectangular filling patterns with the same duty.

In the density unevenness adjustment pattern recording process of S810, the controller 50 drives the carriage motor 57 to move the carriage 21 in the scanning direction, and drives the inkjet head 22 to eject ink from the plurality of nozzles 20. , causes the pattern portion 121 to be recorded. Subsequently, the control device 50 drives the conveying motor 58 to cause the pair of conveying rollers 24 and 25 to convey the recording paper P by the length L of the nozzle row 19 . Controller 50 then causes pattern portion 122 to be recorded in the same manner as described above.

Here, the inkjet head 22 has variations in the amount of ink ejected among the plurality of nozzles 20 due to manufacturing errors or the like. If there is variation in the amount of ink ejected among the plurality of nozzles 20, there is a risk that density unevenness will occur in the printed image. In the printer, a band-shaped image portion, which is a part of an image, is recorded by ejecting ink from a plurality of nozzles 20 while moving the carriage 21 in the scanning direction. The image is recorded by arranging and recording a plurality of images. Therefore, the density unevenness is particularly conspicuous at the boundary between two adjacent belt-like portions.

Therefore, in Modified Example 4, the density unevenness adjustment pattern 120 is printed. By causing the reading unit 5 to read the density unevenness adjustment pattern 120, information on the density of the end of the pattern portion 121 on the side of the pattern portion 122 and information on the density of the end of the pattern portion 122 on the side of the pattern portion 121 can be obtained. , based on these density differences, control for ejecting ink from the plurality of nozzles 20 in the inkjet head 22 is changed to adjust the amount of ink ejected from the plurality of nozzles 20 to be uniform. It can be performed.

Subsequently, the control device 50 executes the same transport process as in S804, S806, and S809 (S811), acquires the head temperature Th in the same manner as in S802 and S807 (S812), and performs the ejection process as in S803 and S808. Timing adjustment pattern recording processing is executed (S813). After that, the same paper discharge process as in S311 is executed (S814), and the process ends.

As a result, three pattern rows 75 arranged at intervals in the transport direction are recorded on the recording paper P. As shown in FIG. Also, on the recording paper P, an ejection amount adjustment pattern 110 is recorded between the first and second pattern rows 75 from the downstream side in the transport direction. Also, on the recording paper P, a density unevenness adjustment pattern 120 is recorded between the second and third pattern rows 75 from the downstream side in the transport direction.

In Modified Example 4, after the plurality of ejection timing adjustment patterns 70 forming each pattern row 75 are recorded on the inkjet head 22 , the plurality of ejection timing adjustment patterns 70 forming the pattern row 75 are then recorded on the inkjet head 22 . By printing the ejection amount adjustment pattern 110 or the density unevenness adjustment pattern 120 before printing, the temperature of the inkjet head 22 can be raised. Accordingly, the head temperature Th when the plurality of ejection timing adjustment patterns 70 are recorded by the inkjet head 22 can be made different between the plurality of pattern rows 75 .

Also, the higher the head temperature Th, the lower the viscosity of the ink in the inkjet head 22 . Therefore, the density of the pattern portions 111 to 114 of the ejection amount adjustment pattern 110 changes depending on the head temperature Th. However, compared to the ink landing position in the scanning direction, the density of the printed image has less influence on the image quality of the image. Therefore, it is effective to adopt the ejection amount adjustment pattern 110 as a test pattern to be printed in order to increase the temperature of the inkjet head 22 as in the fourth modification.

Although the amount of ink ejected from the nozzles 20 varies depending on the head temperature Th, the tendency of variation in the amount of ink ejected among the nozzles 20 is the same regardless of the head temperature Th. Therefore, it is effective to adopt the density unevenness adjustment pattern 120 as a test pattern to be printed in order to raise the temperature of the inkjet head 22 as in the fourth modification.

In the above description, an example in which the present invention is applied to a printer that performs recording by ejecting ink from nozzles has been described, but the present invention is not limited to this. For example, the present invention can be applied to a liquid ejecting apparatus that ejects liquid other than ink, such as liquefied metal or resin.

1 Printer 5 Reading Section 20 Nozzle 21 Carriage 22 Inkjet Head 24, 25 Conveyance Roller Pair 26 Switchback Roller Pair 27 Return Roller Pair 28 Switchback Path 50 Controller 54 Flash Memory 59 Thermistor 70 Ejection Timing Adjustment Pattern 80 Conveyance Amount Adjustment Pattern 100 Printer 101 Temperature sensor 110 Ejection volume adjustment pattern 120 Density unevenness adjustment pattern

Claims (11)

a liquid ejection head having a plurality of nozzles;
a carriage on which the liquid ejection head is mounted and which moves in a scanning direction;
a controller;
The control device is
An operation of driving the liquid ejection head to eject liquid from the plurality of nozzles onto a recording medium while moving the carriage in the scanning direction, the operation for adjusting the landing position of the liquid in the scanning direction. causing the liquid ejection head to perform a first pattern recording operation for recording a first pattern on a recording medium a plurality of times;
After causing the liquid ejection head to perform each first pattern printing operation and before causing the liquid ejection head to perform the next first pattern printing operation, the liquid ejection head is moved while moving the carriage in the scanning direction. a second pattern recording operation for recording a second pattern on the recording medium for adjustment other than the landing position of the liquid in the scanning direction, wherein the liquid is ejected from the plurality of nozzles onto the recording medium; making the temperature of the liquid discharge head different from each other when the liquid discharge head is caused to perform the first pattern recording operation a plurality of times by raising the temperature of the liquid discharge head. A liquid ejection device characterized by: a head temperature detection unit that detects the temperature of the liquid ejection head;
a reading unit that reads the first pattern;
further comprising a storage unit,
The control device is
acquiring the temperature of the liquid ejection head detected by the head temperature detection unit when causing the liquid ejection head to perform the first pattern printing operation;
causing the reading unit to read the plurality of first patterns recorded by the plurality of first pattern recording operations;
Based on the reading result of each first pattern and the temperature of the liquid ejection head detected by the head temperature detection unit during printing of each first pattern, the temperature of the liquid ejection head and the amount of liquid in the scanning direction are determined. storing adjustment information about the relationship with the adjustment amount of the landing position in the storage unit;
When recording an image on a recording medium by moving the carriage in the scanning direction and driving the liquid discharge head to discharge the liquid from the plurality of nozzles, the 2. The liquid ejecting apparatus according to claim 1, wherein the liquid is ejected from the plurality of nozzles at timing according to adjustment information. an upstream transport roller pair disposed upstream of the liquid ejection head in a transport direction intersecting the scanning direction and configured to hold and transport a recording medium in the transport direction;
a pair of downstream-side transport rollers arranged downstream of the liquid ejection head in the transport direction and holding and transporting the recording medium in the transport direction;
The control device is
The recording medium is conveyed in the conveying direction by the upstream conveying roller pair and the downstream conveying roller pair, and the recording medium is held by both the upstream conveying roller pair and the downstream conveying roller pair. 3. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting head is caused to perform the first pattern recording operation in a state. a switchback mechanism that returns the recording medium conveyed to the downstream side in the conveying direction of the downstream conveying roller pair to the upstream side of the upstream conveying roller pair in the conveying direction while turning over the recording medium;
The control device is
A state in which the recording medium is conveyed in the conveying direction by the upstream conveying roller pair and the downstream conveying roller pair, and the recording medium is held by both the upstream conveying roller pair and the downstream conveying roller pair. recording at least one first pattern on one surface of a recording medium by causing the liquid ejection head to perform the first pattern recording operation at least once;
after that, causing the switchback mechanism to return the recording medium to the upstream side in the conveying direction of the pair of upstream conveying rollers while turning over;
After that, the recording medium is conveyed in the conveying direction by the upstream conveying roller pair and the downstream conveying roller pair, and the recording medium is held by both the upstream conveying roller pair and the downstream conveying roller pair. 3. At least one of the first patterns is recorded on the other surface of the recording medium by causing the liquid discharge head to perform the first pattern recording operation at least once in a state where the recording medium 3. The liquid ejecting apparatus according to . The control device is
After causing the liquid ejection head to perform each first pattern recording operation, and before causing the liquid ejection head to perform the next first pattern recording operation, the liquid ejection head is caused to perform the second pattern recording operation. 5. The liquid ejection apparatus according to claim 1, further comprising: causing the liquid ejection head to perform non-ejection driving for driving the liquid ejection head so that the liquid is not ejected from the nozzle. . an environmental temperature acquisition unit that acquires the temperature around the liquid ejection head,
The control device is
When the temperature acquired by the environmental temperature acquisition unit is equal to or lower than a predetermined temperature, causing the liquid ejection head to perform each first pattern printing operation, and then causing the liquid ejection head to perform the next first pattern printing operation. 6. The liquid ejection apparatus according to claim 5, wherein the liquid ejection head is caused to perform the non-ejection drive in addition to causing the liquid ejection head to perform the second pattern recording operation. The control device is
After causing the liquid ejection head to perform each first pattern recording operation, and before causing the liquid ejection head to perform the next first pattern recording operation, the liquid ejection head is caused to perform the second pattern recording operation. 7. The liquid ejection apparatus according to claim 1, further comprising: driving the liquid ejection head to perform flushing for ejecting liquid from the plurality of nozzles. an environmental temperature acquisition unit that acquires the temperature around the liquid ejection head,
The control device is
When the temperature acquired by the environmental temperature acquisition unit is equal to or lower than a predetermined temperature, causing the liquid ejection head to perform each first pattern printing operation, and then causing the liquid ejection head to perform the next first pattern printing operation. 8. The liquid ejection apparatus according to claim 7, wherein the liquid ejection head is caused to perform the flushing in addition to causing the liquid ejection head to perform the second pattern recording operation. further comprising a transport mechanism that transports the recording medium in a transport direction that intersects with the scanning direction;
9. The liquid ejecting apparatus according to claim 1, wherein the second pattern includes a pattern for adjusting a landing position of the liquid in the conveying direction. 10. The liquid ejecting apparatus according to claim 1, wherein the second pattern includes a pattern for adjusting the amount of liquid ejected from the plurality of nozzles. 11. The liquid ejecting apparatus according to claim 1, wherein the second pattern includes a pattern for adjusting variations in the amount of liquid ejected among the plurality of nozzles.

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