JP2010036560A - Liquid jetting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jetting apparatus improve in the accuracy of liquid jetting when conducting liquid jetting to a liquid jetting surface of a medium to be jetted loaded on a retention tray, without lowering throughput. <P>SOLUTION: A correction value δ is a controlling constant number to adjust the timing of inkjet so that the ink lands at a position X1, where an ink-dot is to be formed. When recording is conducted, determination is made regarding whether it is a disk label recording or not (Step S1), and in a case where it is a disk label recording (Step S1: Yes), a correction value table for disk label recording is referred and the correction value δ is set (Step S2). When inkjet is controlled by reciprocating a recording head 62 in a main scanning direction X, the correction value table for disk label recording is referred each time before such control, and a correction value δ, which corresponds to an accumulated value of the amount of transfer of a disk tray 81 then, is selected and set. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus that ejects liquid from a liquid ejecting head onto a liquid ejecting surface of a medium to be ejected.

Here, the liquid ejecting apparatus refers to an ink jet recording apparatus, a copying machine, a facsimile, or the like that ejects ink from a liquid ejecting head such as a recording head to an ejected medium such as recording paper to perform recording on the recording paper. The present invention is not limited to this, and includes a device that ejects a liquid corresponding to a specific application from a liquid ejecting head to an ejected medium instead of ink and adheres the liquid to the ejected medium.
In addition to the recording head described above, the liquid ejecting head includes a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an electrode material used for forming an electrode such as an organic EL display and a surface emitting display (FED) ( Examples thereof include a conductive paste) ejection head, a bioorganic matter ejection head used for biochip manufacturing, and a sample ejection head that ejects a sample as a precision pipette.

  In the liquid ejecting apparatus as described above, the liquid ejecting is performed on the ejection target medium while the liquid ejecting head moves. Accordingly, the liquid ejected from the liquid ejecting head toward the ejected medium flies in the ejecting direction and at the same time reaches the ejected medium while moving in the moving direction of the liquid ejecting head. For this reason, there is a difference between the position where the liquid is ejected from the liquid ejecting head and the position where the liquid actually reaches the ejected medium. The amount of deviation of the liquid landing position varies depending on the moving speed of the liquid ejecting head, and depends on the distance between the liquid ejecting surface of the ejected medium and the liquid ejecting head (hereinafter referred to as “liquid ejecting interval”). Also fluctuate.

  As an example of the prior art aiming at preventing a decrease in liquid ejection accuracy due to such a deviation in the landing position of the liquid, the liquid ejection timing is adjusted based on the moving speed of the liquid ejection head, the liquid ejection interval, and the like. A technique for correcting the deviation of the landing position of the liquid is known (see, for example, Patent Document 1).

  In general, the liquid ejecting apparatus includes a transport unit for transporting the ejection target medium in a predetermined transport direction. For example, in an ink jet printer which is an example of a liquid ejecting apparatus, the ink jet printer is provided on the upstream side and the downstream side in the transport direction from the liquid ejecting area (area where liquid can be ejected by the liquid ejecting head) by the recording head (liquid ejecting head). In general, a structure in which recording paper (a medium to be ejected) is transported in a transport direction by a pair of transport rollers is employed.

  In such a liquid ejecting apparatus, the ejected medium is transported only by the upstream-side transport roller pair or the downstream-side transport roller pair when liquid ejection is performed near the front end or the rear end in the transport direction of the ejected medium. It becomes a state. In such a transport state, the ejected medium is transported in an unstable support state as compared to a state in which the ejected medium is transported by both the upstream transport roller pair and the downstream transport roller pair. As a result, the liquid ejection interval may vary accordingly. Therefore, there is a possibility that the landing position deviation of the liquid exceeding the allowable range occurs near the leading end or the rear end in the transport direction of the ejected medium, and the liquid ejecting accuracy may decrease.

As an example of the prior art for solving such a problem, the liquid ejecting head is disposed in a state where the ejected medium is transported only by the upstream transport roller pair or the downstream transport roller pair. A liquid ejecting nozzle whose liquid ejecting interval falls within a predetermined range is selected from a plurality of liquid ejecting nozzles estimated based on the transport position of the ejected medium and the liquid ejecting is performed using only the selected liquid ejecting nozzle. Liquid ejecting apparatuses that perform the above are well known. According to the related art, since the liquid ejection can be executed while maintaining the liquid ejection interval within a predetermined range in which the deviation of the liquid ejection position is within the allowable range, the liquid ejection is caused by the fluctuation of the liquid ejection interval. It is possible to reduce the possibility that the accuracy is lowered (see, for example, Patent Document 2).
Japanese Patent No. 3557915 JP-A-2004-230817

  However, in the prior art disclosed in Patent Document 2, when performing liquid ejection near the front end or rear end in the transport direction of the ejection target medium, the liquid ejection nozzles are arranged from among a plurality of liquid ejection nozzles arranged in the liquid ejection head. Since the liquid ejection is executed using only some of the selected liquid ejection nozzles, the liquid ejection efficiency is thereby lowered, and the throughput of the liquid ejection apparatus is lowered.

In addition, in an ink jet printer which is an example of a liquid ejecting apparatus, a CD (compact
Disc (disc) and DVD (digital versatile disc), etc., a dedicated tray or the like (hereinafter simply referred to as “holding tray”) loaded with an optical disc is conveyed by a conveying means, and recording (liquid ejection) is performed on the label surface of the optical disc. What has a function is generally known. The holding tray is often made of a thin plate-like member made of, for example, plastic, and is usually made of a material harder than the ejected medium such as recording paper.

  That is, the holding tray has a higher rigidity than the ejected medium such as recording paper and can hardly be deformed. Therefore, in an inkjet printer, when recording is performed on the label surface of the optical disc Di using a holding tray, a support member such as a platen for defining the liquid ejection interval with high accuracy often does not function effectively. . For this reason, the decrease in liquid ejection accuracy due to the variation in the liquid ejection interval tends to occur particularly when recording is performed on the label surface of the optical disc Di using the holding tray.

  SUMMARY An advantage of some aspects of the invention is that liquid ejection is performed on a liquid ejection surface of an ejection medium mounted on a holding tray without reducing throughput in the liquid ejection apparatus. This is to improve the liquid ejection accuracy when performing the operation.

  To achieve the above object, according to a first aspect of the present invention, there is provided a liquid ejecting apparatus that forms dots on an ejected medium by ejecting liquid from a liquid ejecting head that is scanned in a main scanning direction. According to the rigid holding tray for holding the medium, the conveying means for conveying the holding tray in the sub-scanning direction intersecting the main scanning direction, and the formation of dots in the scanning according to the conveying position of the holding tray. And a control unit that varies the ejection timing.

  According to such a feature, it is possible to accurately correct the deviation of the liquid landing position according to the fluctuation of the liquid ejection interval. Further, the present invention varies the ejection timing related to the formation of dots in accordance with the transport position of the holding tray. Therefore, unlike the prior art in which the liquid ejection range is simply limited to a range where the liquid ejection interval is within the allowable range, the liquid ejection efficiency There is no decrease in

  Thereby, according to the liquid ejecting apparatus according to the first aspect of the present invention, in the liquid ejecting apparatus, the liquid ejecting is performed on the liquid ejecting surface of the ejected medium mounted on the holding tray without reducing the throughput. The effect that the liquid-jet accuracy at the time can be improved is obtained.

  In the second aspect of the present invention, one end of the holding tray in the sub-scanning direction is formed so as to recede from the edge of the ejection target medium, and the conveying unit conveys the holding tray while pinching it. The liquid ejecting apparatus according to the first aspect, including a pair of rollers, wherein the ejection timing related to scanning performed in a first state in which the ejection target medium is applied to the roller pair, and the ejection medium The liquid ejecting apparatus is characterized in that the ejection timing relating to scanning performed in the second state deviated from the roller pair is different.

  In the second state in which the ejection medium is removed from the roller pair, for example, a part of the ejection medium may be lifted from the holding tray, and the liquid ejection interval may vary. For this reason, in the present invention, it is preferable to vary the ejection timing related to dot formation in response to fluctuations in the liquid ejection interval in this state. Accordingly, it is possible to further improve the liquid ejection accuracy when performing liquid ejection on the liquid ejection surface of the ejection target medium mounted on the holding tray without reducing the throughput.

  According to a third aspect of the present invention, in the first aspect, the transport unit includes first and second support members for supporting the holding trays arranged in parallel along the sub-scanning direction. The liquid ejecting apparatus according to claim 1, wherein the holding tray is supported by only one of the first and second support members, the ejection timing relating to scanning performed in a first state, and the holding tray is The liquid ejecting apparatus is characterized in that the ejection timing relating to scanning performed in the second state supported by both the first and second support members is different.

  In the liquid ejecting apparatus including such a transport unit, it is preferable to vary the ejection timing related to the formation of dots in response to the variation in the liquid ejecting interval between the first state and the second state. Accordingly, it is possible to further improve the liquid ejection accuracy when performing liquid ejection on the liquid ejection surface of the ejection target medium mounted on the holding tray without reducing the throughput.

A fourth aspect of the present invention is the liquid ejecting apparatus according to the second aspect or the third aspect described above, wherein the holding tray is transferred from the first state to the second state. The liquid ejecting apparatus according to claim 1, wherein when the dots are formed on the ejection medium by a plurality of scans, the control unit varies the ejection timing stepwise between the plurality of scans.
According to such a feature, even if an error occurs in the prediction of the timing for shifting from the first state to the second state, it is possible to accurately vary the ejection timing according to the variation in the liquid ejection interval. Therefore, it is possible to reliably improve the liquid ejection accuracy when performing liquid ejection on the liquid ejection surface of the ejection medium mounted on the holding tray.

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

<Schematic configuration of inkjet printer>
First, a schematic configuration of an ink jet printer 50 as a “liquid ejecting apparatus” according to the invention will be described with reference to FIGS.
FIG. 1 is a main part plan view illustrating a schematic configuration of an ink jet printer 50, and FIG. 2 is a side view of the main part. FIG. 3 is a schematic block diagram of the inkjet printer 50. FIG. 4 is a plan view schematically showing the head surface of the recording head 62. FIG. 5 is a side view of the main part of the inkjet printer 50.

  The ink jet printer 50 as the “liquid ejecting apparatus” according to the present invention includes an automatic feeding device 70 for feeding the recording paper P as the “ejected medium” to the inside of the ink jet printer 50. The ink jet printer 50 includes a transport driving roller 51 and a transport driven roller 52 that constitute a “transport means”. Further, the ink jet printer 50 has a recording head as a “liquid ejecting head” for performing recording by ejecting ink as “liquid” onto the recording surface (liquid ejecting surface) of the recording paper P supported by the platen 53. 62. Further, the ink jet printer 50 includes a discharge driving roller 54 and a discharge driven roller 55 that constitute “conveying means”.

  The automatic feeding device 70 includes a feeding cassette 71, a feeding roller 72, a guide slope 73, feeding guide surfaces 74 and 75, and intermediate feeding roller pairs 7a to 7c. The feeding cassette 71 is placed and accommodated in a state where a plurality of recording papers P are stacked. The feeding roller 72 is rotated by the rotational driving force of the PF motor 57. The feeding guide surfaces 74 and 75 constitute a curved feeding path as shown in the drawing. The guide slope 73 is a slope for guiding the leading edge of the recording paper P between the feed guide surface 74 and the feed guide surface 75. The intermediate feeding roller pairs 7 a to 7 c are roller pairs including a driving roller that is rotated by the rotational driving force of the PF motor 57 and a driven roller that is rotatably supported by the shaft.

  The recording paper P stacked on the feeding cassette 71 is in contact with the outer peripheral surface of the feeding roller 72 by the recording paper P at the top, and along the guide slope 73 by the rotation of the feeding roller 72. Then, the sheet is sent between the feeding guide surface 74 and the feeding guide surface 75. The recording paper P fed between the feeding guide surface 74 and the feeding guide surface 75 along the guide slope 73 advances along the feeding path by the intermediate feeding roller pairs 7a to 7c, and is transported and driven. The sheet is fed to a position where the tip reaches the contact portion between the roller 51 and the conveyance driven roller 52.

  The transport driving roller 51 has a high friction coating on the surface, and rotates by receiving the rotational driving force of the PF motor 57. The transport driven roller 52 is pivotally supported so as to be driven to rotate, and is biased by a biasing means such as a spring (not shown) in contact with the outer peripheral surface of the transport driving roller 51. The recording paper P fed by the automatic feeding device 70 is sandwiched between the transport driving roller 51 and the transport driven roller 52 and is transported on the platen 53 in the sub-scanning direction YF by the driving rotation of the transport driving roller 51.

  The recording head 62 is disposed at the bottom of the carriage 61. A number of ejection nozzles for ejecting ink are disposed on the head surface of the recording head 62 (FIG. 4). More specifically, ejection nozzle groups NY, NM, NC, and NK are disposed on the head surface of the recording head 62. Each of the spray nozzle groups NY, NM, NC, and NK is configured with 180 spray nozzles N1 to N180 arranged along the sub-scanning direction YF. Yellow ink is ejected from each ejection nozzle of the ejection nozzle group NY, magenta ink is ejected from each ejection nozzle of the ejection nozzle group NM, cyan ink is ejected from each ejection nozzle of the ejection nozzle group NC, and ejection nozzles Black ink is ejected from each ejection nozzle of the group NK.

  The carriage 61 can reciprocate in the main scanning direction X (direction intersecting the sub-scanning direction YF) while maintaining a state in which the head surface of the recording head 62 and the recording surface of the recording paper P on the platen 53 are substantially parallel. Further, it is supported by the carriage guide shaft 56. The carriage 61 is connected to an endless belt (not shown) suspended between a driving pulley (not shown) and a driven pulley (not shown) disposed on the rotation shaft of the CR motor 63. The rotational driving force of the CR motor 63 is transmitted through the endless belt and reciprocates in the main scanning direction X.

  The platen 53 includes a first platen rib 531, a second platen rib 532, and a third platen rib 533 arranged in parallel along the sub-scanning direction Y. As illustrated, the first platen rib 531 is provided on the upstream side in the sub-scanning direction Y, the third platen rib 533 is provided on the downstream side in the sub-scanning direction Y, and the second platen rib 532 is connected to the first platen rib 531. It is provided between the third platen rib 533. In addition, the space between the first platen rib 531 and the second platen rib 532 and the space between the second platen rib 532 and the third platen rib 533 are ink for discarding ink when performing so-called borderless recording. It becomes a dumping groove. A large number of first platen ribs 531, second platen ribs 532, and third platen ribs 533 are arranged in parallel in the main scanning direction X with a predetermined interval.

  The recording paper P conveyed on the platen 53 is supported from the back side by the top surfaces of the platen ribs 531 to 533. In the area of the recording paper P supported by the platen 53, dots are formed on the recording surface by ink ejection from the head surface of the recording head 62, and recording is performed. An interval γ (hereinafter referred to as “ink ejection interval γ”) between the head surface and the recording surface of the recording head 62 is defined as an appropriate interval by the top surface of the platen rib (FIG. 5).

  The conveyance driving roller 51, the conveyance driven roller 52, and the platen rib 531 of the platen 53 are disposed so as to satisfy the following positional relationship relatively. First, the vertical interval α between the top surface of the platen rib 531 and the tangent at the apex of the outer peripheral surface of the transport driving roller 51 is set to a predetermined interval. Further, a tangent angle β at a contact point between the outer peripheral surface of the transport driving roller 51 and the outer peripheral surface of the transport driven roller 52 with respect to the top surface of the platen rib 531 is set to a predetermined angle (FIG. 5).

  By providing the interval α and the angle β, the recording paper P conveyed by the rotation of the conveyance driving roller 51 while being sandwiched between the conveyance driving roller 51 and the conveyance driven roller 52 is the top surface of the platen rib 531. The sheet is conveyed in the sub-scanning direction YF while being slid and pressed. As a result, the recording paper P is subjected to a force in a direction to correct warpage, deformation, or the like so as to follow the top surface of the platen rib 531. It is possible to prevent the recording paper P from floating from the top surface.

  The interval α and the angle β are appropriately determined according to the shape and size of each of the transport driving roller 51, the transport driven roller 52, and the platen 53, the size, type, and rigidity of the recording paper P to be used. The The relative positional relationship of the discharge drive roller 54, the discharge driven roller 55, and the platen rib 531 of the platen 53 is the same as described above.

  The recording paper P conveyed on the platen 53 is configured to form dots by ejecting ink from the head surface of the recording head 62 to the recording surface of the recording paper P while the carriage 61 reciprocates in the main scanning direction X; Recording on the recording surface is executed by alternately repeating the operation of conveying in the sub-scanning direction YF by a predetermined conveyance amount by driving rotation of the conveyance drive roller 51. The recording paper P after ink ejection is sandwiched between the discharge drive roller 54 and the discharge driven roller 55, and is conveyed and discharged in the sub-scanning direction YF by the drive rotation of the discharge drive roller 54. The series of recording control is executed by the recording control unit 100 as a “control unit” having a microcomputer control circuit.

  The recording control unit 100 includes a ROM 101, a RAM 102, an ASIC (application specific integrated circuit) 103, a CPU (central processing unit) 104, a nonvolatile memory 105, a PF motor driver 106, a CR motor driver 107, and a head driver 108. .

  The ROM 101 stores a recording control program (firmware) necessary for controlling the ink jet printer 50 by the CPU 104. The RAM 102 is used as a work area for the CPU 104 and a storage area for image data and the like. The CPU 104 executes a recording control program, and performs arithmetic processing for executing recording control of the inkjet printer 50 and other necessary arithmetic processing. The nonvolatile memory 105 stores various data necessary for arithmetic processing by the recording control program. The ASIC 103 performs various calculations for controlling the speeds of the PF motor 57 and the CR motor 63, and sends motor control signals based on the calculation results to the PF motor driver 106 and the CR motor driver 107. Further, the ASIC 103 calculates and generates a control signal for the recording head 62 and sends it to the head driver 108 to control ink ejection of the recording head 62. Further, the ASIC 103 has an interface function with the personal computer 301.

  The rotary encoder 31 for detecting the rotation amount of the transport driving roller 51 is composed of a rotary scale 311 and a rotary scale sensor 312. The rotary scale 311 has a large number of slits formed on a concentric circle at equal intervals along the outer periphery, and rotates in conjunction with the rotation of the transport driving roller 51. The rotary scale sensor 312 is a sensor for detecting a slit of the rotary scale 311. An output signal of the rotary scale sensor 312 that changes with the rotation of the transport driving roller 51 is output to the CPU 104 via the ASIC 103.

  The linear encoder 32 for detecting the movement amount of the carriage 61 includes a linear scale 321 and a linear scale sensor 322. The linear scale 321 is disposed in the vicinity of the carriage 61 substantially in parallel with the main scanning direction X, and a large number of slits are formed at equal intervals. The linear scale sensor 322 is a sensor for detecting a slit of the linear scale 321 and is mounted on the carriage 61. An output signal of the linear scale sensor 322 in which the pulse period corresponding to the amount of movement of the carriage 61 in the main scanning direction X varies with the moving speed is output to the CPU 104 via the ASIC 103.

  The PW sensor 33 for detecting the recording paper P is a non-contact optical sensor and is disposed at the bottom of the carriage 61. The tray operation button 34 is a button for the user to operate a disk tray support device 80 described later. The detection signal of the PW sensor 33 and the operation signal of the tray operation button 34 are output to the CPU 104 via the ASIC 103.

  Furthermore, the ink jet printer 50 includes a disk tray support device 80. The disc tray support device 80 includes a disc tray 81 as a “holding tray”, a left support arm 82 and a right support arm 83. The disc tray 81 is supported by the left support arm 82 and the right support arm 83 so as to be movable in the sub-scanning direction YF, and has a mounting portion 811 for mounting the optical disc. The mounting portion 811 is formed with a convex portion 812 into which a hole provided in the center of the optical disc is fitted. Hereinafter, the configuration of the disk tray support device 80 will be described in detail with reference to FIG.

<Disc tray support device 80>
FIG. 6 is a plan view of a principal part illustrating the configuration of the disk tray support device 80.
The left support arm 82 has a convex portion 821 formed on one end side pivoted to the disc tray 81 and a convex portion 822 formed on the other end side engaged with the left guide groove 8L. The left guide groove 8L is provided on the back surface side of the member constituting the feeding guide surface 75 (FIG. 2). In the right support arm 83, a convex portion 831 formed on one end side is pivotally connected to the disc tray 81, and a convex portion 832 formed on the other end side is engaged with the right guide groove 8R. The right guide groove 8R is provided on a tray support plate (not shown) that supports the disc tray 81 from the bottom surface side.

  In the disc tray support device 80 having such a configuration, the left support arm 82 and the right support arm 83 are folded (substantially parallel to the main scanning direction X) when the disc tray 81 is located closest to the reverse feed direction YR. A state that becomes a posture). Then, as the disc tray 81 moves in the sub-scanning direction YF from that state, the left support arm 82 is rotationally displaced along the left guide groove 8L, and the right support arm 83 is moved along the right guide groove 8R. Rotating displacement. With such a support structure, the disc tray support device 80 can move in the sub-scanning direction YF and the reverse feed direction YR with a movement width that is significantly longer than the length of the disc tray 81 in the sub-scanning direction YF. Can be supported. As a result, the disc tray 81 built in the rear side of the inkjet printer 50 can be moved to a position that largely protrudes from the front discharge port. Further, since the disk tray 81 can be downsized to the minimum necessary size, it is possible to prevent the ink jet printer 50 from being enlarged by incorporating the disk tray 81 therein.

<Conveyance control of disc tray 81>
Next, conveyance control of the disc tray 81 by the recording control unit 100 will be described with reference to FIGS.

7 to 10 are main part plan views of the ink jet printer 50. FIG.
The ink jet printer 50 includes a rotating gear 84. The rotating gear 84 rotates in both directions by the rotational driving force of a dedicated motor (not shown) whose rotation is controlled by the recording control unit 100. The tooth portion of the rotating gear 84 meshes with a tooth portion (not shown) provided on the side portion of the disk tray 81.

  When the tray operation button 34 is pressed from the state in which the disc tray 81 is in the standby position (FIG. 7), the recording control unit 100 first rotates the rotary gear 84 in the rotation direction indicated by the symbol A. As a result, the disc tray 81 moves to a position where the front end in the sub-scanning direction YF comes into contact with the contact portion between the transport driving roller 51 and the transport driven roller 52. (Fig. 8). From this state, the recording control unit 100 rotates the transport driving roller 51 in the rotation direction (hereinafter referred to as “forward rotation direction”) in which the disk tray 81 is transported in the sub-scanning direction YF. As a result, the disk tray 81 is conveyed in the sub-scanning direction YF by the rotation of the conveyance drive roller 51 and protrudes from the discharge port on the front side of the inkjet printer 50 (FIG. 9). In this state, the inkjet printer 50 is in a state in which the user can mount the optical disc Di as the “ejected medium” on the mounting portion 811 of the disc tray 81.

  When the tray operation button 34 is pressed again from this state, the recording control unit 100 carries the conveyance drive roller in the rotation direction (hereinafter referred to as “reverse rotation direction”) in which the disc tray 81 is conveyed in the reverse feed direction YR. Rotate 51. Thereby, the disc tray 81 is conveyed in the reverse feeding direction YR by the rotation of the conveyance driving roller 51. Then, the recording control unit 100 stops the rotation of the transport driving roller 51 when the disc tray 81 is fed back to a predetermined position. As a result, the disc tray 81 is stopped at a position where the label surface of the optical disc Di becomes a predetermined recording start position, and recording on the label surface of the optical disc Di is performed in the same procedure as the recording execution procedure on the recording paper P. Can be executed (FIG. 10).

  From this state, the recording control unit 100 detects the presence / absence and mounting position of the optical disc Di with the PW sensor 33, and when the optical disc Di is correctly mounted on the mounting portion 811, the recording control on the label surface of the optical disc Di is performed. Start. On the other hand, when the optical disc Di cannot be detected, the disc tray 81 is moved back to the standby position (FIG. 7), and when the optical disc Di is not properly installed, an error display or the like is performed.

  After the recording on the label surface of the optical disc Di is completed, the recording control unit 100 conveys the disc tray 81 in the sub-scanning direction YF to a position where the recording control portion 100 protrudes from the discharge port on the front side of the inkjet printer 50 (FIG. 9). ). In this state, the ink jet printer 50 is in a state in which the user can remove the recorded optical disc Di from the mounting portion 811 of the disc tray 81. When the tray operation button 34 is pressed again, the recording control unit 100 sends the disc tray 81 back to the standby position (FIG. 7).

<Recording control of label surface of optical disc Di>
Next, recording control of the label surface of the optical disc Di by the recording control unit 100 will be described with reference to FIGS.

  From the state in which the disc tray 81 is stopped at the position where the label surface of the optical disc Di becomes a predetermined recording start position (FIG. 10), the recording control unit 100 performs the same procedure as the recording execution procedure on the recording paper P described above. Recording of Di on the label surface is executed. More specifically, while the recording head 62 is reciprocated in the main scanning direction X, ink is ejected from the recording head 62 onto the label surface of the optical disc Di, and the transport driving roller 51 is moved in the forward rotation direction. Recording on the label surface of the optical disc Di is executed by alternately repeating the operation of transporting the disc tray 81 in the sub-scanning direction YF with a predetermined transport amount by rotating.

  When recording on the label surface of the optical disk Di, in order to avoid the label surface of the optical disk Di from being damaged by the discharge driven roller 55 made of a toothed roller, a release means (not shown) The state where the discharge driven roller 55 is displaced to a position away from the discharge drive roller 54 is maintained.

  FIGS. 11 to 14 illustrate the transport state of the disk tray 81 during execution of recording on the label surface of the optical disk Di.

FIG. 11 illustrates a state immediately after starting recording from the recording start position.
In this state, the disc tray 81 is sandwiched between the transport driving roller 51 and the transport driven roller 52 and is transported in the sub-scanning direction YF without being engaged with the discharge drive roller 54. In this state, the disc tray 81 is conveyed in the sub-scanning direction YF in an inclined posture that is inclined downward in the sub-scanning direction YF as shown in the figure by providing the interval α and the angle β (FIG. 5). It will be. In addition, the disc tray 81 is in a state in which the vicinity of the front end is supported by the first platen rib 531 while the front end slightly enters the ink discarding groove portion between the first platen rib 531 and the second platen rib 532 of the platen 53. . Here, the theoretical ink ejection interval γr at the time of recording on the label surface of the optical disc Di is a relatively stable support state in which the disc tray 81 is supported by both the transport drive roller 51 and the discharge drive roller 54 (FIG. 13 is set as a reference. For this reason, the ink ejection interval γ1 in this state is larger than the theoretical ink ejection interval γr.

FIG. 12 illustrates a state before the disk tray 81 is supported by both the transport drive roller 51 and the discharge drive roller 54.
The disc tray 81 in this state is still sandwiched between the transport driving roller 51 and the transport driven roller 52 and transported in the sub-scanning direction YF without being engaged with the discharge drive roller 54. The vicinity is supported by the second platen rib 532 or the third platen rib 533. For this reason, the ink ejection interval γ2 at this time is smaller than the ink ejection interval γ1 in FIG. 11 although it is in a state larger than the theoretical ink ejection interval γr.

  FIG. 13 illustrates a state in which the disc tray 81 is supported by both the transport drive roller 51 and the discharge drive roller 54. The ink ejection interval in this state is a substantially theoretical ink ejection interval γr as shown in the figure.

FIG. 14 shows that the optical disc Di mounted on the disc tray 81 is sandwiched between the transport drive roller 51 and the transport driven roller 52 in a state where the disc tray 81 is supported by both the transport drive roller 51 and the discharge drive roller 54. The state immediately after leaving is illustrated.
In this state, by providing the interval α and the angle β (FIG. 5), the disc tray 81 is bent and deformed slightly in a concave shape. On the other hand, the optical disk Di mounted on the disk tray 81 is in a state in which almost no external force is applied after it is released from the nipping by the transport driving roller 51 and the transport driven roller 52. Therefore, the rear end side of the sub-scanning direction YF is slightly lifted from the mounting portion 811 of the disc tray 81 as shown in the drawing. Accordingly, the ink ejection interval γ3 at this time is smaller than the theoretical ink ejection interval γr.

  Thus, when recording is performed on the label surface of the optical disc Di mounted on the disc tray 81, the ink ejection interval γ varies depending on the transport state of the disc tray 81. Such a change in the ink ejection interval γ affects the control for correcting the deviation of the ink landing position caused by executing the ink ejection while moving the recording head 62 in the main scanning direction X.

  Here, the control for correcting the deviation of the ink landing position conventionally performed in the ink jet printer 50 will be described with reference to FIG.

  FIG. 15 is a front view schematically showing a state where the ink ejected from the ejection nozzles of the recording head 62 lands on the label surface of the optical disc Di.

  The ink ejected from the recording head 62 to the label surface of the optical disc Di is landed on the label surface of the optical disc Di while flying in the ejecting direction and simultaneously moving in the moving direction of the recording head 62. Therefore, there is a difference between the position where the ink is ejected from the recording head 62 and the position where the ink is actually landed on the label surface of the optical disc Di. Therefore, the recording control unit 100 performs recording while correcting the deviation of the ink landing position by adjusting the ink ejection timing.

  For example, when ink is ejected while moving the recording head 62 in the forward direction XL, the ink is landed at a position d before the position X1 where the ink dot is to be formed so that the ink is landed at the position X1 where the ink dot is to be formed. When the ejection nozzle moves, ink is ejected from the ejection nozzle. Similarly, when ink is ejected while moving the recording head 62 in the backward direction XR, ink is ejected from the ejection nozzle when the ejection nozzle moves to a position that is a distance d before the position X1 where the ink dot is to be formed. Spray. The moving position of the recording head 62 can be specified from the output signal of the linear encoder 32, for example.

  By performing such correction for adjusting the ink ejection timing, it is possible to accurately form ink dots at the position X1 on the label surface of the optical disc Di where the ink dots are to be formed. Further, when performing bidirectional recording in which ink is ejected in both directions of the reciprocating operation of the recording head 62, the ink dots formed while moving the recording head 62 in the forward direction XL and the recording head 62 in the backward direction XR. It is possible to prevent relative displacement from occurring between the ink dots formed while being moved.

  The distance d at which the ink landing position is accurately corrected in the control for correcting the deviation of the ink landing position described above varies depending on the fluctuation of the ink ejection interval γ. For example, in the ink ejection intervals γ1 and γ2 that are larger than the theoretical ink ejection interval γr, the ink flight distance becomes longer by that amount, so the ink movement distance in the movement direction of the recording head 62 becomes longer. Accordingly, the ink is landed at the position X2 that is shifted to the moving direction side from the position X1 where the ink dot is to be formed. On the other hand, at the ink ejection interval γ3 which is smaller than the theoretical ink ejection interval γr, the ink flight distance is shortened accordingly, and therefore the ink travel distance in the moving direction of the recording head 62 is shortened. Therefore, the ink will land at the position X3 that is shifted from the position X1 where the ink dot is to be formed to the opposite side of the moving direction.

  As described above, the conventional control for correcting the deviation of the ink landing position is not accurately executed when the ink ejection interval γ varies during the execution of recording. Therefore, the recording control unit 100 of the ink jet printer 50 according to the present invention shifts the ink landing position caused by performing ink ejection while moving the recording head 62 in the main scanning direction X according to the variation of the ink ejection interval γ. Change the control to correct.

  The procedure for changing the control for correcting the deviation of the ink landing position according to the present invention will be described below with reference to FIGS.

  FIG. 16 is a flowchart of the procedure for setting the correction value δ when recording is performed on the label surface of the optical disc Di. FIG. 17 illustrates an example of a correction value table when recording is performed on the label surface of the optical disc Di. FIG. 18 is a graph schematically showing the relationship between the transport position of the disc tray 81 and the ink ejection interval γ.

  The correction value δ is a control constant for adjusting the ink ejection timing so that the ink reaches the position X1 where the ink dot is to be formed by setting the distance d in FIG. 15 to an appropriate distance. The distance d increases as the correction value δ increases, and decreases as the correction value δ decreases. More specifically, the correction value δ is determined based on the moving speed of the recording head 62 during ink ejection and the ink ejection interval γ. The recording control unit 100 first determines whether or not the disk label recording (recording on the label surface of the optical disk Di) is performed at the time of recording (step S1). In the case of disc label recording (Yes in step S1), the correction value δ is set with reference to the disc label recording correction value table (FIG. 17) (step S2).

  At this time, the recording control unit 100 holds the accumulated value of the transport amount in the sub-scanning direction YF of the disc tray 81 starting from the recording start position on the label surface of the optical disc Di, and transports each time the disc tray 81 is transported. Update by accumulating the amount. The carry amount of the disc tray 81 can be specified from the output signal of the rotary encoder 31, for example. The recording control unit 100 refers to the correction value table for disk label recording each time before executing the control for reciprocating the recording head 62 in the main scanning direction X and ejecting ink. The correction value δ corresponding to the accumulated value of the carry amount of the disc tray 81 is selected and set.

  The correction value table for disc label recording corresponds to threshold values N1 to N10 of accumulated values of the carry amount of the disc tray 81 starting from the recording start position on the label surface of the optical disc Di, and N1 to N10, respectively. It is a data table composed of correction values δ1 to δ10, and is stored in advance in the nonvolatile memory 105. The threshold values N1 to N10 of the accumulated values of the carry amounts correspond to the respective sections obtained by dividing the transport distance of the disk tray 81 from the start of recording to the end of recording into 10 sections, and from the recording start position to the end position of each section. This is a conveyance amount corresponding to the conveyance distance. The correction values δ1 to δ10 corresponding to the threshold values N1 to N10 may be set in accordance with, for example, an average value of the ink ejection interval γ in each corresponding section in advance through experiments and the like. .

  As shown in FIG. 18, it is preferable to set the boundary of each section at a position where the ink ejection interval γ varies greatly. Furthermore, the length of each section does not need to be the same length, and in order to realize the setting of the correction value δ with higher accuracy, the range in which the ink ejection interval γ fluctuates greatly is divided into short distances. Is preferred.

  In the embodiment, in the sections 1 to 4, the disk tray 81 is sandwiched between the transport driving roller 51 and the transport driven roller 52, and the discharge driving roller 54 and the disk tray 81 are not engaged with each other. The vicinity of the front end corresponds to a range in which the first platen rib 531 is supported (the state illustrated in FIG. 11).

  In the sections 5 to 8, the disk tray 81 is sandwiched between the transport drive roller 51 and the transport driven roller 52, the discharge drive roller 54 and the disk tray 81 are not engaged, and the vicinity of the front end of the disk tray 81 is the first. This corresponds to the range where the second platen rib 532 or the third platen rib 533 is supported (the state shown in FIG. 12).

  The section 9 corresponds to a range in which the disk tray 81 is supported by both the transport driving roller 51 and the discharge driving roller 54 (the state illustrated in FIG. 13). The section 10 corresponds to a range in which the optical disc Di mounted on the disc tray 81 is in a state (state shown in FIG. 14) in which the optical disc Di is separated from the nipping by the transport driving roller 51 and the transport driven roller 52.

  In this embodiment, the transport distance of the disc tray 81 from the start of recording to the end of recording is divided into 10 sections. However, the number of divisions is not particularly limited to 10, and a more accurate correction value δ. In order to realize this setting, it is preferable to set the number of divisions as large as possible.

  FIG. 19 is a flowchart of the procedure for setting the ink ejection start position by the recording head 62.

  In the operation of ejecting ink by reciprocating the recording head 62 in the main scanning direction X, the recording control unit 100 is based on the moving speed of the recording head 62, the ink ejection interval γ, and the position of the optical disc Di each time. An ink ejection start position in the direction XL or the backward direction XR is set. Here, the moving speed of the recording head 62 is a preset default value. Further, the position of the optical disc Di can be specified by executing the center position detection of the optical disc Di or the like by the PW sensor 33 mounted on the carriage 61 before starting the recording. On the other hand, the ink ejection interval γ varies depending on the transport position of the disk tray 81. Therefore, the recording control unit 100 sets the ink ejection start position in the forward direction XL or the backward direction XR according to the following procedure.

  The recording control unit 100 first determines whether or not the disk label is recorded when recording is performed (step S11). If it is disc label recording (Yes in step S11), it is then determined whether or not the direction in which the recording head 62 is moved is the forward direction XL (step S12). When the direction in which the recording head 62 is moved is the forward direction XL (Yes in step S12), the ink ejection start position in the forward direction XL is set according to the accumulated value of the transport amount of the disk tray 81 at that time. (Step S13). On the other hand, when the direction in which the recording head 62 is moved is the backward direction XR (No in step S12), the ink ejection start position in the backward direction XR is set according to the accumulated value of the transport amount of the disk tray 81 at that time. Set (step S14).

  As described above, according to the present invention, the disc tray 81 is sandwiched between the transport drive roller 51 and the transport driven roller 52, and the discharge drive roller 54 and the disc tray 81 are not engaged with each other. Thus, when the disc tray 81 is conveyed, it is possible to accurately correct the deviation of the ink landing position in accordance with the fluctuation of the ink ejection interval γ caused by the disc tray 81. Also, unlike the prior art in which the ink ejection range is simply limited to a range in which the ink ejection interval γ is within the allowable range, the ink ejection efficiency does not decrease. Therefore, it is possible to improve the recording accuracy when recording is performed on the label surface of the optical disc Di mounted on the disc tray 81 without reducing the throughput.

  In the present invention, the optical disc mounted on the disc tray 81 is used even in a relatively stable support state in which the disc tray 81 is supported by both the transport drive roller 51 and the discharge drive roller 54 as in the above embodiment. It is more preferable to change the correction value δ corresponding to the fluctuation of the ink ejection interval γ caused by the separation of Di from the nipping by the conveyance driving roller 51 and the conveyance driven roller 52. Thereby, it is possible to further improve the recording accuracy when recording is performed on the label surface of the optical disc Di mounted on the disc tray 81 without reducing the throughput.

  Further, in the present invention, it is preferable that the correction value δ is changed stepwise over a plurality of times before and after the timing at which the ink ejection interval γ varies greatly. That is, the correction value δ is not changed at a stroke when the ink ejection interval γ fluctuates greatly, but the ink is ejected while reciprocating the recording head 62 in the main scanning direction X several times before and after the timing. It is preferable to change in stages during the operation. As a result, even if an error occurs in the prediction of the timing at which the ink ejection interval γ varies greatly, the correction value δ can be accurately changed according to the variation in the ink ejection interval γ. Therefore, it is possible to reliably improve the recording accuracy when recording is performed on the label surface of the optical disc Di mounted on the disc tray 81.

  In this embodiment, the timing at which the ink ejection interval γ fluctuates is, for example, the section 4, the boundary between the sections 8 and 9, or the boundary between the sections 9 and 10 (FIG. 18). For example, the transition section extending before and after the boundary portion may be further subdivided and divided into a plurality of sections, and the correction value δ for each section may be set so that the correction value δ changes stepwise. Alternatively, the correction value δ may be changed stepwise in a certain step every time the recording head 62 reciprocates from the start point of the transition section.

  Further, in the present invention, the correction value δ may be set to a different correction value δ for each of the injection nozzles N1 to N180 of the injection nozzle groups NY, NM, NC, and NK. Accordingly, in a state where the ink ejection intervals γ of the ejection nozzles N1 to N180 are different from each other (for example, the state illustrated in FIGS. 11 and 12), the recording is executed by setting an accurate correction value δ with higher accuracy. Is possible.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

The principal part top view which illustrated schematic structure of the inkjet printer. The principal part side view which illustrated schematic structure of the inkjet printer. 1 is a schematic block diagram of an inkjet printer. FIG. 3 is a plan view schematically showing the head surface of the recording head. The principal part side view of an inkjet printer. The principal part top view which illustrated the structure of the disc tray support apparatus. The principal part top view of an inkjet printer. The principal part top view of an inkjet printer. The principal part top view of an inkjet printer. The principal part top view of an inkjet printer. The principal part side view which illustrated the conveyance state of the disc tray during recording execution. The principal part side view which illustrated the conveyance state of the disc tray during recording execution. The principal part side view which illustrated the conveyance state of the disc tray during recording execution. The principal part side view which illustrated the conveyance state of the disc tray during recording execution. FIG. 3 is a front view illustrating a state where ink is landed on a label surface of an optical disc. 10 is a flowchart of a procedure for setting a correction value δ at the time of disc label recording. Correction value table when recording a disc label. 6 is a graph illustrating a relationship between a tray conveyance position and an ink ejection interval γ. 6 is a flowchart of a procedure for setting an ink ejection start position by a recording head.

Explanation of symbols

50 Inkjet printer, 51 Conveyance drive roller, 52 Conveyance driven roller, 53 Platen, 54 Discharge drive roller, 55 Discharge driven roller, 56 Carriage guide shaft, 70 Automatic feeding device, 80 Disc tray support device, 81 Disc tray, 82 Left Support arm, 83 Right support arm, Di optical disc, P recording paper, X width direction, YF transport direction

Claims (4)

A liquid ejecting apparatus that forms dots on an ejected medium by ejecting liquid from a liquid ejecting head that is scanned in a main scanning direction,
A rigid holding tray for holding the ejected medium;
Transport means for transporting the holding tray in a sub-scanning direction intersecting the main scanning direction;
A liquid ejecting apparatus comprising: a control unit configured to vary ejection timing related to dot formation in the scanning according to a transport position of the holding tray. The one end in the sub-scanning direction of the holding tray is formed so as to recede from the edge of the ejected medium, and the conveying means includes a roller pair that conveys the holding tray while pinching it. The liquid ejecting apparatus according to claim 1,
The ejection timing related to the scanning performed in the first state where the ejection target medium is applied to the roller pair is different from the ejection timing related to the scanning performed in the second state where the ejection target medium is separated from the roller pair. A liquid ejecting apparatus. The liquid ejecting apparatus according to claim 1, wherein the transport unit includes first and second support members for supporting the holding trays arranged in parallel along the sub-scanning direction.
The ejection timing related to the scanning performed in the first state in which the holding tray is supported by only one of the first and second support members, and the holding tray of the first and second support members The liquid ejecting apparatus according to claim 1, wherein the ejection timing relating to scanning performed in the second state supported by both is different. The liquid ejecting apparatus according to claim 2, wherein
In the process of transporting the holding tray that transitions from the first state to the second state, when dots are formed on the ejected medium by a plurality of scans, the control unit performs the scan between the plurality of scans. A liquid ejecting apparatus characterized by varying the ejection timing stepwise.

Images