JP2018149706A - Liquid discharge device and setting method of discharge range - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress reduction of conveyance accuracy of a medium caused by variation of movement amounts of a conveyance belt.SOLUTION: A liquid discharge device 1 includes: a conveyance belt 10 which supports a medium P and conveys the medium P in a conveyance direction A; a drive roller 8 which rotates and moves the conveyance belt 10; a plurality of discharge parts 7 on which nozzles N, which can discharge a liquid, are formed along the conveyance direction A; and a control part 31 which carries out control of printing operation of discharging the liquid from a discharge range 42 of the discharge parts 7 and forming an image on the medium P. A discharge length L1 as a length of the discharge range 42 in the conveyance direction A is an integral multiple of a first belt movement amount L2 as a movement amount of the conveyance belt 10 when the drive roller 8 rotates half around.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a liquid discharge apparatus and a discharge range setting method.

Conventionally, various liquid ejection devices have been used. Among these, a liquid ejecting apparatus that includes a transport belt that transports a medium and that discharges a liquid such as ink onto a medium transported by the transport belt is disclosed. In a liquid ejecting apparatus including a transport belt for transporting such a medium, there may be a case where the transport accuracy of the medium is reduced due to variation in the amount of movement of the transport belt.
In addition, regarding reduction in medium conveyance accuracy, for example, in Patent Document 1, in a configuration in which a medium is nipped and conveyed by a conveyance roller that is a pair of rollers, the number of nozzles used in the inkjet head is an even multiple of the half circumference of the conveyance roller. It is disclosed that the amount of deviation of the transport distance of the medium is reduced by using the above.

JP 2008-119983 A

  However, the configuration in which the medium is conveyed by the conveyance belt and the configuration in which the medium is nipped and conveyed by the pair of rollers are greatly different, and the technology required for conveying the medium is also greatly different. And in patent document 1, there is no description about the structure provided with the conveyance belt which conveys a medium. For this reason, it is unclear in Patent Document 1 without any disclosure or suggestion as to how the technique of Patent Document 1 should be adopted for a configuration including a conveyor belt.

  Therefore, an object of the present invention is to suppress a decrease in medium conveyance accuracy due to variations in the amount of movement of the conveyance belt.

  A liquid ejection apparatus according to a first aspect of the present invention for solving the above problems includes a conveyance belt that supports a medium and conveys the medium in a conveyance direction, and a drive roller that moves the conveyance belt by rotating. An ejection unit in which a plurality of nozzles capable of ejecting liquid are formed in the transport direction; and a control unit that controls a printing operation for ejecting the liquid from an ejection range of the ejection unit to form an image on the medium. The discharge length, which is the length of the discharge range in the transport direction, is an integral multiple of the first belt movement amount, which is the movement amount of the transport belt when the drive roller is rotated halfway. Features.

  According to this aspect, the discharge length is an integral multiple of the first belt movement amount, which is the movement amount of the transport belt when the drive roller is rotated halfway. That is, the ejection length corresponding to the desired conveyance amount of the medium in the printing operation is made to correspond to the movement amount of the conveyance belt based on the half circumference of the drive roller. The rotational axis of the drive roller may be displaced from the center position. In this case, the amount of movement of the transport belt when the drive roller is rotated is not constant. At this time, if the discharge length is an integral multiple of the first belt movement amount, the movement amount of the conveyor belt varies periodically (specifically, a movement amount that is shorter than the ideal state by a predetermined amount). And a movement amount that is longer than the ideal state by a predetermined amount alternately appear). Accordingly, it is possible to easily set a correction value or the like for the movement amount of the conveyor belt. Also, if the position where the amount of movement of the conveying belt relative to the amount of rotation of the driving roller is maximum or minimum is set as the rotation start position, the movement of the conveying belt every half circumference of the driving roller even if the rotation axis of the driving roller is deviated from the center position. The amount is constant (half the circumference of the drive roller). For this reason, in the printing operation, the amount of movement of the conveyor belt can be easily made constant by moving the conveyor belt based on the half circumference of the drive roller. Therefore, it is possible to suppress a decrease in the conveyance accuracy of the medium due to variations in the movement amount of the conveyance belt.

  The liquid ejection device according to a second aspect of the present invention is the liquid ejection device according to the first aspect, wherein in the transport direction, the length of the range where the nozzles of the ejection unit are formed is longer than the first belt movement amount, The controller sets the nozzle to be used from the nozzles so that the discharge length is an integral multiple of the first belt movement amount.

  According to this aspect, the length of the range in which the nozzles are formed in the transport direction is longer than the first belt movement amount. For this reason, it is possible to preferably set the nozzles to be used, and to suitably set the discharge length to an integral multiple of the first belt movement amount.

  In the liquid ejection device according to a third aspect of the present invention, in the first or second aspect, the length of a range in which the nozzles of the ejection unit are formed in the transport direction is the first belt movement amount. It is an integral multiple of.

  According to this aspect, the length of the range in which the nozzles are formed in the transport direction is an integral multiple of the first belt movement amount. Therefore, the discharge length can be easily made an integral multiple of the first belt movement amount without adjusting the discharge range.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the liquid ejection apparatus includes a detection unit that detects a position of the driving roller in the rotation direction, and the control unit includes the printing unit. In the operation of transporting the medium in operation, the rotation angle of the drive roller is set on the basis of the movement amount of the transport belt calculated based on the detection result by the detection unit.

  According to this aspect, in the medium conveyance operation in the printing operation, the rotation angle of the drive roller is set based on the movement amount of the conveyance belt calculated based on the detection result by the detection unit. That is, the transport belt is not moved based on the rotation amount of the drive roller, but is moved based on the travel amount of the transport belt calculated based on the detection result by the detection unit. For this reason, even if the rotation axis of the driving roller is deviated from the center position, the conveyance belt can be moved with high accuracy by performing the calculation in consideration of the deviation from the center position of the rotation axis in advance.

  In the liquid ejection device according to a fifth aspect of the present invention, in the fourth aspect, the rotation angle of the driving roller corresponding to the position in the rotation direction of the driving roller is related to the amount of movement of the transport belt. A storage unit storing the table, wherein the control unit calculates a movement amount of the transport belt with respect to a rotation angle of the drive roller using the table.

  According to this aspect, the movement amount of the conveyance belt with respect to the rotation angle of the driving roller using the table in which the rotation angle of the driving roller and the movement amount of the conveyance belt are associated with the position in the rotation direction of the driving roller. Is calculated. For this reason, the amount of movement of the conveyor belt can be easily calculated.

  The liquid ejection device according to a sixth aspect of the present invention is the liquid ejection device according to any one of the first to fifth aspects, wherein the control unit rotates the driving roller in the medium transport operation in the printing operation. Is set to a position where the amount of movement of the conveying belt relative to the amount of rotation of the driving roller is maximized or minimized.

  According to this aspect, in the medium conveyance operation in the printing operation, the rotation start position of the drive roller is set to a position where the movement amount of the conveyance belt with respect to the rotation amount of the drive roller is maximized or minimized. When the rotation start position of the driving roller is set to a position where the moving amount of the conveying belt with respect to the rotating amount of the driving roller is maximum or minimum, even if the rotation axis of the driving roller is deviated from the center position, The amount of movement is constant (half the circumference of the drive roller).

  According to a seventh aspect of the present invention, there is provided a discharge range setting method comprising: a transport belt that supports a medium and transports the medium in a transport direction; a drive roller that moves the transport belt by rotating; and a liquid that can be ejected A discharge unit in which a plurality of nozzles are formed along the transport direction, and a control unit that controls a printing operation for forming an image on the medium by discharging the liquid from a discharge range of the discharge unit, and A method for setting a discharge range in a liquid discharge apparatus, wherein a length of a range in which the nozzles of the discharge unit are formed is longer than a maximum discharge length when the discharge range is maximum in the transport direction, A test pattern for detecting the first belt movement amount, which is the movement amount of the conveyance belt when half-circulated, is formed, and based on the test pattern, in the conveyance direction of the discharge range. The discharge length is the length, and setting an integer multiple of said first belt moving amount.

  According to this aspect, the length of the range in which the nozzles are formed in the transport direction is longer than the maximum discharge length when the discharge range is the maximum. For this reason, based on the test pattern, it is possible to suitably set the nozzle to be used, and to suitably set the discharge length to an integral multiple of the first belt movement amount.

1 is a schematic side view illustrating a printing apparatus according to a first embodiment of the invention. 1 is a block diagram illustrating a printing apparatus according to a first embodiment of the invention. 1 is a schematic bottom view illustrating a main part of a printing apparatus according to Embodiment 1 of the present invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. 1 is a schematic side view illustrating a main part of a printing apparatus according to a first embodiment of the invention. FIG. 6 is a schematic bottom view illustrating a main part of a printing apparatus according to a second embodiment of the invention.

Hereinafter, a printing apparatus which is an example of a liquid ejection apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
[Example 1] (FIGS. 1 to 10)
Initially, the outline | summary of the printing apparatus 1 which concerns on Example 1 of this invention is demonstrated.
FIG. 1 is a schematic side view of a printing apparatus 1 according to the present embodiment.

  The printing apparatus 1 of this embodiment includes a feeding unit 2, a transport mechanism 3, a printing mechanism 4, a cleaning mechanism 15, and a winding mechanism 28. The feeding unit 2 can feed out a roll R1 of a medium (print medium) P for printing. The transport mechanism 3 is a mechanism for transporting the medium P in the transport direction A by an adhesive belt 10 (a transport belt constituted by an endless belt) that supports the medium P on the support surface F to which the adhesive is attached. The printing mechanism 4 reciprocates (reciprocates) a carriage 16 including a print head 7 serving as an ejection unit that ejects ink (liquid) in a scanning direction B that intersects the conveyance direction A of the medium P. This is a mechanism for performing printing (discharging ink). The cleaning mechanism 15 is a mechanism for cleaning the adhesive belt 10. The take-up mechanism 28 is a mechanism having a take-up shaft 17 that takes up the medium P. “Scanning” means that the carriage 16 is moved in the scanning direction B. For example, during printing, the carriage 16 is moved in the scanning direction B while ejecting ink from the print head 7. It is done.

  As the medium P, a material to be printed can be used. The material to be printed refers to fabrics, clothes, and other clothing products to be printed. The fabric includes woven fabrics, knitted fabrics, non-woven fabrics, etc. of natural fibers such as cotton, hemp, silk, wool, etc., chemical fibers such as nylon, or composite fibers obtained by mixing these. In addition, for clothes and other clothing products, in addition to furniture such as T-shirts, handkerchiefs, scarves, towels, handbags, cloth bags, curtains, sheets, bedspreads, etc., before sewing The existing cloth before and after cutting is also included.

  Further, as the medium P, in addition to the material to be printed, plain paper, high-quality paper, exclusive paper for inkjet printing such as glossy paper, and the like can be used. Further, as the medium P, for example, a plastic film that is not surface-treated for inkjet printing (that is, an ink absorbing layer is not formed), a paper or other base material coated with plastic, and What has a plastic film adhere | attached on base materials, such as paper, can also be used. The plastic is not particularly limited, and examples thereof include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

  The feeding unit 2 includes a rotating shaft 5 that also serves as a setting position of the roll R1 of the medium P for printing, and transports the medium P from the roll R1 set on the rotating shaft 5 through the driven rollers 6 and 30. It is a configuration that can be extended to. When the medium P is fed out to the transport mechanism 3, the rotating shaft 5 rotates in the rotation direction C.

The transport mechanism 3 includes an adhesive belt 10 that places and transports the medium P fed from the feeding unit 2, a drive roller 8 that moves the adhesive belt 10 in the direction E, and a driven roller 9. . The adhesive belt 10 is hung on the driving roller 8 and the driven roller 9, and in the printing apparatus 1 of this embodiment, the driving roller 8 and the driven roller 9 are positioned horizontally. The cross-linking direction is horizontal. The medium P is stuck and placed by being pressed against the support surface F of the adhesive belt 10 by the pressing roller 12. Note that when the medium P is conveyed, the driving roller 8 rotates in the rotation direction C. A rotation shaft 20 (see FIGS. 4 to 10) of the drive roller 8 includes a detection unit 18 (specifically, a position in the rotation direction C of the drive roller 8 and a rotation amount (rotation angle) of the drive roller 8). Is provided with an encoder).
However, the endless belt as the conveying belt is not limited to the adhesive belt. For example, an electrostatic adsorption type endless belt may be used.
Further, a support portion 19 that can support the adhesive belt 10 is provided in a region below the adhesive belt 10 of the present embodiment and facing the pressing roller 12 via the adhesive belt 10. Since the support part 19 supports the adhesive belt 10, it can suppress that the adhesive belt 10 vibrates with moving the adhesive belt 10. FIG.
Further, the pressing roller 12 of the present embodiment can reciprocate (swing) along the transport direction A in order to prevent contact marks from being attached to the medium P by contacting the same place of the medium P for a certain period of time. It has a configuration. However, the pressing roller 12 is not limited to such a configuration.

The printing mechanism 4 includes a carriage moving unit 29 (see FIG. 2) that reciprocates the carriage 16 including the print head 7 in the scanning direction B. In FIG. 1, the scanning direction B is a direction perpendicular to the paper surface.
During printing, printing is performed by reciprocating the carriage 16 including the print head 7, but the conveyance mechanism 3 stops the conveyance of the medium P during printing scanning (while the carriage 16 is moving). In other words, the reciprocating scanning of the carriage 16 and the conveyance of the medium P are alternately performed during printing. That is, at the time of printing, the transport mechanism 3 intermittently transports the medium P (the adhesive belt 10 is intermittently moved) corresponding to the reciprocating scanning of the carriage 16.

  The cleaning mechanism 15 of the adhesive belt 10 includes a cleaning brush 13 configured by connecting a plurality of cleaning rollers in the rotation axis direction, and a tray 14 containing a cleaning agent for cleaning the cleaning brush 13.

The winding mechanism 28 is a mechanism that winds the medium P that has been printed and is transported from the transport mechanism 3 via the driven roller 11. A winding paper tube or the like is set on the winding shaft 17. By winding the medium P, the medium P can be wound as a roll R2.
Note that FIG. 1 shows a state where the surface on which printing is performed uses the outer roll R1, and the surface on which printing is performed is wound outward. For this reason, both the rotating shaft 5 and the winding shaft 17 are rotated in the rotation direction C. However, the printing apparatus 1 according to the present embodiment can use the roll R1 whose inner surface is printed, and can be wound so that the printed surface is on the inner side. That is, both the rotating shaft 5 and the winding shaft 17 can be rotated in the direction opposite to the rotating direction C.

Next, an electrical configuration of the printing apparatus 1 according to the present embodiment will be described.
FIG. 2 is a block diagram of the printing apparatus 1 of the present embodiment.
The control unit 31 is a control unit for controlling the printing apparatus 1. The control unit 31 includes an I / F (interface) 32, a CPU 33, a storage unit 45, and the like.
The I / F 32 is used to exchange data such as ejection data with the PC 46 as an external device. The CPU 33 is an arithmetic processing unit for controlling the entire printing apparatus 1 based on an input signal from the detector group 47 including the detection unit 18 and the like. The storage unit 45 also includes a ROM that stores various control programs executed by the CPU 33, a RAM and an EEPROM for securing an area for storing programs executed by the CPU 33, a work area, and the like.

  The CPU 33 uses the control circuit 44 to drive the driving roller 8 that moves the adhesive belt 10 in the transport direction A, the carriage moving unit 29 that moves the carriage 16 including the print head 7 in the scanning direction B, and printing that discharges ink onto the medium P. The drive of the head 7 and each device (not shown) is controlled.

With this configuration, the control unit 31 according to the present embodiment can control a printing operation for forming an image on the medium P by discharging ink from a discharge range 42 (see FIG. 3) of the print head 7 described later. It is possible.
Further, the control unit 31 can calculate the movement amount of the adhesive belt 10 based on the rotation amount of the driving roller 8 detected by the detection unit 18. Specifically, a table in which the rotation angle of the drive roller 8 and the amount of movement of the adhesive belt 10 corresponding to the position in the rotation direction C of the drive roller 8 is stored in the storage unit 45. The controller 31 can calculate the amount of movement of the adhesive belt 10 corresponding to the rotation angle of the drive roller 8 using the table.
The detection unit 18 of the present embodiment is an encoder that can detect the amount of rotation of the drive roller 8, but is not limited to such a configuration. For example, the detector 18 can measure the amount of movement of the adhesive belt 10. Good.

Next, the print head 7 that is a main part of the printing apparatus 1 of the present embodiment will be described.
FIG. 3 is a schematic bottom view of the print head 7 which is a main part of the printing apparatus 1 of the present embodiment.

As shown in FIG. 3, the print head 7 according to the present embodiment includes nozzle rows 34 to 41 configured by arranging a plurality of nozzles N along the transport direction A (in a direction intersecting the scanning direction B). Have. The printing apparatus 1 according to the present embodiment is configured to eject cyan ink, magenta ink, yellow ink, and black ink. The nozzle rows 34 and 38 are cyan ink, the nozzle rows 35 and 39 are magenta ink, and the nozzle row. 36 and 40 correspond to yellow ink, and nozzle rows 37 and 41 correspond to black ink.
However, the arrangement of the nozzles N, the types of ink that can be used (the number of nozzle rows), and the like are not limited to the present embodiment.

Here, as shown in FIG. 1, the printing apparatus 1 according to the present embodiment includes an adhesive belt 10 that supports the medium P and conveys the medium P in the conveyance direction A, and an adhesive belt 10. And a driving roller 8 that moves the adhesive belt 10 by rotating. Further, as shown in FIG. 3, there is provided a print head 7 in which a plurality of nozzles N capable of ejecting liquid ink are formed along the transport direction A. Further, as shown in FIG. 2, a control unit 31 is provided that controls a printing operation for forming an image on the medium P by ejecting ink from the ejection range 42 of the print head 7.
The discharge length L1 (see FIG. 3), which is the length of the discharge range 42 in the transport direction A, is the first belt movement amount L2 that is the movement amount of the adhesive belt 10 when the drive roller 8 is rotated halfway. It is an integral multiple of (see FIGS. 4 to 7).
Thus, in the printing apparatus 1 of the present embodiment, the discharge length L1 is an integer multiple of the first belt movement amount L2. That is, the adhesive belt 10 based on the discharge length L1 corresponding to a desired conveyance amount of the medium P in the printing operation (for example, an appropriate one-time conveyance amount in the intermittent conveyance of the medium P) and the half circumference of the driving roller 8. The movement amount (first belt movement amount L2) can be made to correspond to each other. Although details will be described later with reference to FIGS. 4 to 7, the rotation shaft 20 of the drive roller 8 may be displaced from the center position 23, and in this case, the movement of the adhesive belt 10 when the drive roller 8 is rotated. The amount is no longer constant. At this time, if the discharge length L1 is an integral multiple of the first belt movement amount L2, the movement amount of the adhesive belt 10 varies periodically (specifically, a predetermined amount from the ideal state). Only a short movement amount and a movement amount longer than the ideal state by a predetermined amount appear alternately). Therefore, it is possible to easily set a correction value or the like for the movement amount of the adhesive belt 10. Further, when the position where the amount of movement of the adhesive belt 10 relative to the rotation amount of the drive roller 8 is maximized or minimized is set as the rotation start position, even if the rotation shaft 20 of the drive roller 8 is deviated from the center position 23, The amount of movement of the adhesive belt 10 every half circumference is constant (half the circumference of the drive roller 8). For this reason, in the printing operation, the movement amount of the adhesive belt 10 can be easily made constant by moving the adhesive belt 10 based on the half circumference of the drive roller 8. Therefore, the printing apparatus 1 of the present embodiment is configured to be able to suppress a decrease in the conveyance accuracy of the medium P due to variations in the amount of movement of the adhesive belt 10.
In addition, “the position where the movement amount of the adhesive belt 10 with respect to the rotation amount of the driving roller 8 is maximized or minimized is set as the rotation start position”, for example, as shown in FIGS. When the rotation of the driving roller 8 is started, the urging position 25 that is the position where the force is most applied from the driving roller 8 to the adhesive belt 10 coincides with the linear position in the bridging direction passing through the rotation shaft 20 of the driving roller 8. It is to be arranged.

In the printing apparatus 1 of the present embodiment, the discharge length L1 is set to be one time the first belt movement amount L2 (that is, the discharge length L1 and the first belt movement amount L2 are equal), but the discharge length L1. May be an integer multiple of twice or more the first belt movement amount L2. In the printing apparatus 1 of the present embodiment, the discharge length L1 is set to be one time the first belt movement amount L2, so printing is performed in one pass (the same portion of the medium P is printed by one scan of the print head 7). In this case, the drive roller 8 is rotated halfway along with the one-time conveyance in the intermittent conveyance of the medium P. However, for example, when the discharge length L1 is twice the first belt movement amount L2, when the printing is performed in one pass, the driving roller 8 is rotated once in association with one conveyance in the intermittent conveyance of the medium P. When the discharge length L1 is set to be three times the first belt movement amount L2, when the printing is performed in one pass, the driving roller 8 is caused to make one and a half rotations along with the one-time conveyance in the intermittent conveyance of the medium P.
The “movement amount of the adhesive belt 10” means the movement amount of the adhesive belt 10 in the region facing the print head 7.

Here, the first belt movement amount L <b> 2 can be assumed in advance based on design information of the transport mechanism 3 of the printing apparatus 1. The first belt movement amount L2 assumed in this way is assumed to be an assumed belt movement amount LX. However, the first belt movement amount L2 of the printing apparatus 1 that is actually assembled may be different from the assumed belt movement amount LX due to the influence of individual differences in parts, assembly accuracy, and the like. In order to cope with such fluctuations of the first belt movement amount L2 with respect to the assumed belt movement amount LX, the printing apparatus 1 of the present embodiment is configured to be able to print by changing the discharge range 42.
Further, considering that the discharge range 42 varies in accordance with the actual first belt movement amount L2, the length L0 of the range where the nozzles N of the print head 7 are formed is longer than the assumed belt movement amount LX. ing. Further, even when the first belt movement amount L2 becomes the maximum within an allowable error, the length L0 of the range where the nozzles N of the print head 7 are formed is longer than the first belt movement amount L2. Has been. The discharge range 42 in FIG. 3 represents the discharge range when the first belt movement amount L2 is the same as the assumed belt movement amount LX. As shown in FIG. 3, the print head 7 according to the present embodiment is further in the direction along the conveyance direction A even if the discharge length L1 is an integral multiple (here, 1 time) of the first belt movement amount L2. The nozzles N are formed so that the nozzles N remain. For example, when the first belt movement amount L2 is longer than the assumed belt movement amount LX, the remaining nozzle N (nozzle N outside the discharge range 42 in FIG. 3) is also used, and the discharge range. You just have to expand.
In summary, the printing apparatus 1 according to the present embodiment sets the length L0 of the range in which the nozzles N of the print head 7 are formed in the transport direction A to be longer than the first belt movement amount L2, and sends these nozzles to the control unit 31. It is possible to set the nozzle to be used from among N and make the discharge length L1 an integral multiple of the first belt movement amount L2.
Since the printing apparatus 1 of the present embodiment thus makes the length L0 of the range in which the nozzles N are formed in the transport direction A longer than the first belt movement amount L2, the use nozzle is preferably set. The discharge length L1 can be preferably an integral multiple of the first belt movement amount L2.
Note that “the control unit 31 sets a nozzle to be used from among these nozzles N and sets the discharge length L1 to an integral multiple of the first belt movement amount L2”, for example, detects the first belt movement amount L2. For example, the control unit 31 sets a nozzle to be used based on the test pattern, and sets the discharge length L1 to an integral multiple of the first belt movement amount L2.

That is, the adhesive belt 10 that supports the medium P and conveys the medium P in the conveyance direction A, the drive roller 8 that moves the adhesive belt 10 by rotating the adhesive belt 10 and rotates, and the ink. A print head 7 in which a plurality of ejectable nozzles N are formed along the transport direction A, and a control unit 31 that controls a printing operation for forming an image on the medium P by ejecting ink from the ejection range 42 of the print head 7. In the transport direction A, the length L0 of the range in which the nozzles N of the print head 7 are formed is longer than the maximum discharge length when the discharge range 42 is maximum. Then, a test pattern for detecting the first belt movement amount L2 that is the movement amount of the adhesive belt 10 when the drive roller 8 is made to make a half turn is formed, and based on the test pattern, the discharge range 42 The discharge length L1 is the length in the feeding direction A, you can perform setting of a discharge range to be set to an integral multiple of the first belt movement amount L2.
By executing such a setting method of the discharge range, the length L0 of the range in which the nozzles N are formed in the transport direction A is longer than the maximum discharge length when the discharge range 42 is the maximum, and therefore, based on the test pattern. Thus, the nozzles to be used are preferably set, and the discharge length L1 can be suitably made an integral multiple of the first belt movement amount L2.

Next, the relationship between the position in the rotation direction C of the drive roller 8 and the rotation amount (rotation angle) of the drive roller 8 and the first belt movement amount L2 that is the movement amount of the adhesive belt 10 will be described.
Here, FIG. 4 is a schematic side view showing the driving roller 8 and the adhesive belt 10 in the vicinity of the driving roller 8 which are the main parts of the printing apparatus 1 of the present embodiment, and the rotating shaft 20 of the driving roller 8 is driven. The state which has not shifted | deviated from the center position 23 of the roller 8 is represented. 5 to 8 are schematic side views showing the driving roller 8 as viewed from the same direction as FIG. 4, and the rotation shaft 20 of the driving roller 8 is deviated from the center position 23 of the driving roller 8. Represents a state. 5 to 8 are different in the position of the drive roller 8 in the rotational direction C, FIG. 5 is a state where the rotary shaft 20 is on the lower side in the vertical direction with respect to the center position 23, and FIG. FIG. 7 and FIG. 8 show a state where the rotary shaft 20 is in a position displaced in the horizontal direction with respect to the center position 23.

As shown in FIG. 4, if the rotation axis 20 of the driving roller 8 is not shifted from the center position 23 of the driving roller 8, if the rotation angle of the driving roller 8 is constant, the rotation angle is any angle. Even so, the amount of movement of the adhesive belt 10 is constant. For example, when the rotation angle of the drive roller 8 is 180 °, the movement amount of the adhesive belt 10 (the first belt movement amount L2) no matter what the position of the drive roller 8 in the rotation direction C is. Is 2πr (π is the circumference ratio, and r is the distance from the rotating shaft 20 of the driving roller 8 to the neutral position 24 of the adhesive belt 10).
As shown in FIG. 4, the biasing position 25 (for example, the position farthest from the rotation center of the adhesive belt 10 which is an endless belt) is a linear position 21 in the bridging direction passing through the rotation shaft 20 and This is because it matches 22. With such a configuration, when the rotation angle of the driving roller 8 is 180 °, the movement amount of the adhesive belt 10 (first belt movement amount L2) is always 2πr.
Here, the “neutral position 24 of the adhesive belt 10” means a position where the portion (curved portion) of the adhesive belt 10 that is hung on the driving roller 8 is not stretched or contracted. In addition, the adhesive belt 10 is displaced in the extending direction outside the neutral position 24 and in the contracting direction inside the neutral position 24.

  On the other hand, as shown in FIGS. 5 to 8, when the rotation shaft 20 of the driving roller 8 is deviated from the center position 23 of the driving roller 8, the driving roller 8 is constant even if the rotation angle of the driving roller 8 is constant. The amount of movement of the adhesive belt 10 is not constant depending on the position in the rotation direction C of 8 and the rotation angle of the driving roller 8. The rotational radius of the driving roller 8 is large when the distance from the rotational shaft 20 to the biasing position 25 is long even if the rotational angle of the driving roller 8 is constant because the rotational shaft 20 is displaced from the center position 23. As a result, the amount of movement of the adhesive belt 10 increases, and in the state where the distance from the rotary shaft 20 to the biasing position 25 is short, the rotational radius of the drive roller 8 is small, so the amount of movement of the adhesive belt 10 is small. It is.

  Here, the discharge length L1 which is the length of the discharge range 42 in the transport direction A is the movement length in the rotation direction C when the drive roller 8 is rotated once (360 ° rotation) (movement of the adhesive belt 10). When the driving roller 8 is rotated once, the amount of movement of the adhesive belt 10 is always constant. Therefore, the amount of movement of the adhesive belt 10 (first belt movement amount L2) is constant. Become. However, if the discharge length L1 is an integral multiple of the amount of movement of the adhesive belt 10 when the drive roller 8 is rotated once, the size of the print head 7 and the arrangement of the nozzles N can be greatly limited. In order not to impose large restrictions on the size of the print head 7 and the arrangement of the nozzles N, it is desirable that the discharge length L1 can be set to an integral multiple of the amount of movement of the adhesive belt 10 when the drive roller 8 is rotated halfway. .

However, for example, even when the rotation angle of the drive roller 8 is 180 °, the movement amount of the adhesive belt 10 may not be constant depending on the position of the drive roller 8 in the rotation direction C.
For example, in the state shown in FIG. 5, the urging position 25 does not coincide with the linear positions 21 a and 22 a in the bridging direction passing through the rotation shaft 20. When the driving roller 8 is rotated halfway (turned 180 °) in such a state, the portion located at the linear position 21a moves to the position of the linear position 22b as shown in FIG. The part which has been located moves to the position of the linear position 21b. For this reason, the first belt movement amount L2 which is the movement amount of the adhesive belt 10 is the movement amount L2a shown in FIG.
On the other hand, when the driving roller 8 is further rotated halfway (turned 180 °) from the state shown in FIG. 6, as shown in FIG. 5, the portion located at the linear position 21b reaches the position of the linear position 22a. The part which moved and was located in the linear position 22b moves to the position of the linear position 21a. For this reason, the first belt movement amount L2 that is the movement amount of the adhesive belt 10 is the movement amount L2b represented in FIG.
When the movement amount L2a and the movement amount L2b are compared, the movement amount L2a is clearly larger than the movement amount L2b. That is, even if the rotation angle of the drive roller 8 is 180 °, the first belt movement amount L2 is not constant.

Therefore, the printing apparatus 1 according to the present embodiment determines the position of the driving roller 8 in the rotation direction C from the state illustrated in FIG. 7 and the state illustrated in FIG. 8 (from the state illustrated in FIG. 7 to the driving roller 8. In a half-circumferential state) can be used as a reference. In other words, the biasing position 25 can be made to coincide with the linear positions 21c and 22c (linear positions 21d and 22d) in the bridging direction passing through the rotation shaft 20.
When the driving roller 8 is rotated halfway (turned 180 °) in the state shown in FIG. 7, as shown in FIG. 8, the portion located at the linear position 21 c moves to the position of the linear position 22 d, The portion located at the position 22c moves to the position of the linear position 21d. The first belt movement amount L2 that is the movement amount of the adhesive belt 10 at this time is the movement amount L2c.
Further, when the driving roller 8 is rotated halfway (turned 180 °) in the state shown in FIG. 8, the portion located at the linear position 21d moves to the position at the linear position 22c as shown in FIG. The portion located at the straight line position 22d moves to the position at the straight line position 21c. The first belt movement amount L2, which is the movement amount of the adhesive belt 10 at this time, is the movement amount L2d.
Comparing the movement amount L2c and the movement amount L2d, both the movement amount L2c and the movement amount L2d are half the circumference of the drive roller 8 and are equal. That is, if the rotation angle of the drive roller 8 is 180 °, the first belt movement amount L2 is constant.

  Note that the drive roller 8 is positioned in the rotation direction C of the drive roller 8 and rotated by the control unit 31 based on the detection result of the detection unit 18. Further, the position of the driving roller 8 shown in FIG. 7 is expressed as a position where the distance from the rotation shaft 20 to the urging position 25 is the longest and the movement amount of the adhesive belt 10 with respect to the rotation amount of the driving roller 8 is the maximum. it can. The position of the drive roller 8 shown in FIG. 8 is expressed as a position where the distance from the rotation shaft 20 to the biasing position 25 is the shortest and the movement amount of the adhesive belt 10 with respect to the rotation amount of the drive roller 8 is minimum. it can.

As described above, in the printing apparatus 1 according to the present embodiment, the control unit 31 sets the rotation start position of the driving roller 8 in the conveyance operation of the medium P in the printing operation to the amount of movement of the adhesive belt 10 with respect to the rotation amount of the driving roller 8. Can be set to a position (corresponding to the state of FIG. 7) or a position (corresponding to the state of FIG. 8) to be the minimum.
That is, the printing apparatus 1 according to the present embodiment rotates the driving roller 8 by setting the rotation start position of the driving roller 8 to a position where the movement amount of the adhesive belt 10 with respect to the rotation amount of the driving roller 8 is maximized or minimized. Even if the shaft 20 is deviated from the center position 23, the movement amount of the adhesive belt 10 every half of the drive roller 8 is constant (half the circumference of the drive roller 8).
The “transport operation of the medium P in the printing operation” refers to transporting the medium P in the transport direction A using the transport mechanism 3 between the formation of the image on the medium P by the print head 7.

Further, the printing apparatus 1 according to the present embodiment can perform so-called multi-pass printing in which the same portion of the medium P is divided into a plurality of scans of the print head 7 and printed.
Next, the rotation operation of the drive roller 8 when printing in multi-pass will be described.
9 corresponds to FIG. 7 in the position of the drive roller 8 in the rotation direction C, and the movement of the adhesive belt 10 between each pass (rotation of the drive roller 8) when printing in multi-pass (4 passes) It is a schematic side view of the drive roller 8 for demonstrating the case where the rotation angle of the drive roller 8 is made constant. 10 corresponds to FIG. 7 in the position of the driving roller 8 in the rotation direction C, and the movement of the adhesive belt 10 between the passes (rotation of the driving roller 8) when printing in multi-pass (four passes). FIG. 6 is a schematic side view of the driving roller 8 for explaining a case in which the amount of movement of the adhesive belt 10 is adjusted to be constant.

  As shown in FIG. 9, when printing in four passes using the printing apparatus 1 of this embodiment, if the rotation angle of the drive roller 8 between each pass is constant (angle Θ), The longer the distance is, the longer the moving distance (moving amount of the adhesive belt 10) in the rotation direction C of the driving roller 8 is. In FIG. 9, the moving distance in the rotation direction C of the driving roller 8 becomes shorter as the moving distance LΘ1, the moving distance LΘ2, the moving distance LΘ3, and the moving distance LΘ4.

  For this reason, when the rotation angle of the driving roller 8 is used as a reference, the amount of movement of the adhesive belt 10 between the passes changes. Therefore, in the printing apparatus 1 of the present embodiment, the adhesive belt 10 between the passes is changed. The control unit 31 adjusts the rotation amount (rotation angle) of the drive roller 8 according to the position in the rotation direction C of the drive roller 8 so that the movement amount becomes constant. FIG. 10 shows that when printing is performed in four passes using the printing apparatus 1 of the present embodiment, the rotation angle of the driving roller 8 between each pass is adjusted to an angle Θa, an angle Θb, an angle Θc, and an angle Θd. This represents a state in which the movement distance of the drive roller 8 in the rotation direction C is all constant at the movement distance L2c / 4 (1/4 of the movement amount L2c).

Specifically, the printing apparatus 1 of this embodiment includes a detection unit 18 that detects the position of the drive roller 8 in the rotation direction C, and the control unit 31 detects the detection unit 18 in the transport operation of the medium P in the printing operation. Based on the detection result obtained by the above, the movement amount of the adhesive belt 10 with respect to the rotation angle of the driving roller 8 corresponding to the position of the driving roller 8 in the rotation direction C is calculated, and the calculated movement amount of the adhesive belt 10 is used as a reference. In addition, the rotation angle of the drive roller 8 can be set.
That is, the printing apparatus 1 according to the present embodiment does not move the adhesive belt 10 based on the rotation amount of the driving roller 8 but calculates the adhesiveness corresponding to the deviation between the rotation shaft 20 and the center position 23. The adhesive belt 10 can be moved based on the movement amount of the belt 10. For this reason, even if the rotating shaft 20 of the driving roller 8 is deviated from the center position 23, the adhesive belt 10 is moved with high accuracy by performing calculation in consideration of the deviation of the rotating shaft 20 from the center position 23 in advance. Can be made.

  Specifically, the printing apparatus 1 of this embodiment includes the storage unit 45 as described above, and the storage unit 45 has a rotation angle of the driving roller 8 corresponding to the position in the rotation direction C of the driving roller 8. And a table in which the amount of movement of the adhesive belt 10 is related. And the control part 31 can calculate the moving amount | distance of the adhesive belt 10 with respect to the rotation angle of the drive roller 8 using this table. The printing apparatus 1 of the present embodiment is configured to be able to easily calculate the amount of movement of the adhesive belt 10 by using the table in this way.

To explain the above description from another point of view, the printing apparatus 1 according to the present embodiment includes a carriage moving unit 29 as a moving mechanism that reciprocally moves the print head 7 in the scanning direction B intersecting the transport direction A. . Then, the control unit 31 alternately repeats the movement of the print head 7 in the scanning direction B accompanied by the ejection of ink in the printing operation and the movement of the adhesive belt 10 to form an image on the medium P. The length of one pass in the transport direction A (for example, ¼ of the discharge length L1) in the range in which ink is ejected from the print head 7 with one movement (one pass) in the scanning direction B. The first belt movement amount L2 is set to 1 / integer (for example, 1/4 of the movement amount L2c), and each movement amount (for example, 1/4 of the movement amount L2c) associated with one movement of the adhesive belt 10 is any. In addition, the rotation amount of the driving roller 8 can be adjusted for each movement of the adhesive belt 10 so as to be a length corresponding to one pass (for example, ¼ of the discharge length L1).
As described above, the printing apparatus 1 according to the present exemplary embodiment has a length corresponding to one pass in the transport direction A within a range in which ink is ejected from the print head 7 with one movement of the print head 7 in the scanning direction B. The length is set to 1 / integer of the first belt moving amount L2, and each moving amount accompanying one movement of the adhesive belt 10 (moving one intermittent movement) is the length of one path. The rotation amount of the drive roller 8 can be adjusted for each movement of the adhesive belt 10. That is, when printing by multi-pass with the so-called serial type printing apparatus 1, the adhesive belt 10 is not moved based on the rotation amount of the driving roller 8 instead of the intermittent movement of the adhesive belt 10 based on the rotation amount of the driving roller 8. The amount of movement can be used as a reference. For this reason, even if the rotating shaft 20 of the driving roller 8 is deviated from the center position 23, the deviation from the center position 23 of the rotating shaft 20 is taken into consideration in advance (for example, information on the deviation is stored in the storage unit 45). For example, even when printing in multi-pass, the adhesive belt 10 can be intermittently moved with high accuracy for each movement. When printing in multi-pass, the movement amount (line feed amount) of the adhesive belt 10 in each pass as a reference may not be uniform between the passes. For example, the line feed amount in the first pass may be smaller than the line feed amount in the second pass. In such a case, it is preferable that the discharge length L1 is changed according to the pass, and the discharge length L1 is an integral multiple of the line feed amount in each pass.

  In this embodiment, since the discharge length L1 is set to be one time the first belt movement amount L2, the conveyance direction A discharged from the print head 7 with one movement of the print head 7 in the scanning direction B is shown. The length of one pass at ¼ is 1/4 of the discharge length L1, and the amount of movement associated with one movement of the adhesive belt 10 is ¼ of the amount of movement L2c. However, as described above, the discharge length L1 may be an integer multiple of twice or more the first belt movement amount L2. Therefore, for example, when the discharge length L1 is twice the first belt movement amount L2, 1 in the transport direction A discharged from the print head 7 with one movement of the print head 7 in the scanning direction B is 1 The length of the path can be 1/8 of the discharge length L1, and the amount of movement associated with one movement of the adhesive belt 10 can be 1/4 of the amount of movement L2c.

[Example 2] (FIG. 11)
Next, the printing apparatus 1 according to the second embodiment will be described in detail with reference to the accompanying drawings.
FIG. 11 is a schematic bottom view of the print head 7 which is a main part of the printing apparatus 1 of the present embodiment, and corresponds to FIG. 3 of the printing apparatus 1 of the first embodiment. In addition, the structural member which is common in the said Example 1 is shown with the same code | symbol, and abbreviate | omits detailed description.
The configuration of the printing apparatus 1 of the present embodiment is the same as that of the printing apparatus 1 of the first embodiment except for the print head 7.

As shown in FIG. 11, in the printing apparatus 1 of the present embodiment, the length L0 of the range in which the nozzles N of the print head 7 are formed in the transport direction A is the length of the discharge range 42 in the transport direction A. Is the same as the discharge length L1 and is an integral multiple of the first belt movement amount L2. For this reason, the discharge length L1 can be easily made an integral multiple of the first belt movement amount L2 without adjusting the discharge range 42 or the like.
Such a configuration can be realized, for example, by setting the discharge range 42 so as to be an integral multiple of the first belt movement amount L2 and preparing the print head 7 corresponding thereto.

  In addition, this invention is not limited to the said Example, A various deformation | transformation is possible within the range of the invention described in the claim, and it cannot be overemphasized that they are also contained in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Printing apparatus (liquid discharge apparatus), 2 ... Delivery part, 3 ... Conveyance mechanism, 4 ... Printing mechanism,
5 ... rotating shaft, 6 ... driven roller, 7 ... print head (discharge unit), 8 ... driving roller,
9 ... driven roller, 10 ... adhesive belt (conveyor belt), 11 ... driven roller,
12 ... Pressing roller, 13 ... Cleaning brush, 14 ... Tray, 15 ... Cleaning mechanism,
16 ... Carriage, 17 ... Winding shaft, 18 ... Detection part, 19 ... Support part,
20 ... Rotation axis of the drive roller 8, 21 ... Linear position in the bridging direction passing through the rotation axis 20,
21a to 21d ... linear position in the bridging direction passing through the rotary shaft 20,
22 ... Linear position in the bridging direction passing through the rotary shaft 20,
22a to 22d ... linear position in the bridging direction passing through the rotary shaft 20,
23 ... Center position of the driving roller 8, 24 ... Neutral position, 25 ... Biasing position,
28 ... winding mechanism, 29 ... carriage moving unit, 30 ... driven roller, 31 ... control unit,
32 ... I / F (interface), 33 ... CPU, 34 to 41 ... nozzle row,
42 ... discharge range, 44 ... control circuit, 45 ... storage unit, 46 ... PC, 47 ... detector group,
F: Support surface, L0: Length of the range where the nozzle N is formed, L1: Discharge length,
L2 ... first belt movement amount, N ... nozzle, P ... medium, R1 ... roll of medium P,
R2: Roll of medium P

Claims (7)

A conveying belt that supports the medium and conveys the medium in the conveying direction;
A drive roller that moves the conveyor belt by rotating;
A discharge unit in which a plurality of nozzles capable of discharging liquid are formed along the transport direction;
A control unit that controls a printing operation for forming an image on the medium by discharging the liquid from a discharge range of the discharge unit;
The discharge length, which is the length of the discharge range in the transport direction, is an integral multiple of the first belt movement amount, which is the movement amount of the transport belt when the drive roller is rotated halfway. Discharge device. The liquid ejection apparatus according to claim 1,
In the transport direction, the length of the range where the nozzles of the discharge unit are formed is longer than the first belt movement amount,
The liquid ejecting apparatus according to claim 1, wherein the control unit sets a nozzle to be used from the nozzles so that the ejection length is an integral multiple of the first belt movement amount. The liquid ejection device according to claim 1 or 2,
In the transport direction, a length of a range in which the nozzles of the discharge unit are formed is an integral multiple of the first belt movement amount. The liquid ejection apparatus according to any one of claims 1 to 3,
A detection unit for detecting a position of the drive roller in the rotation direction;
The control unit sets a rotation angle of the driving roller based on a movement amount of the conveyance belt calculated based on a detection result by the detection unit in the medium conveyance operation in the printing operation. A liquid ejection device. The liquid ejection apparatus according to claim 4, wherein
A storage unit that stores a table in which the rotation angle of the drive roller and the amount of movement of the transport belt correspond to the position in the rotation direction of the drive roller;
The liquid ejecting apparatus according to claim 1, wherein the control unit calculates a movement amount of the transport belt with respect to a rotation angle of the drive roller using the table. The liquid ejection apparatus according to any one of claims 1 to 5,
The control unit sets the rotation start position of the drive roller to a position where the movement amount of the conveyance belt relative to the rotation amount of the drive roller is maximum or minimum in the medium conveyance operation in the printing operation. A liquid ejecting apparatus. A conveying belt that supports the medium and conveys the medium in the conveying direction; a driving roller that moves the conveying belt by rotating; and a discharge unit that includes a plurality of nozzles that can discharge liquid along the conveying direction. A control unit that controls a printing operation for forming an image on the medium by discharging the liquid from the discharge range of the discharge unit, and the range in which the nozzles of the discharge unit are formed in the transport direction Is a method for setting a discharge range in a liquid discharge apparatus that is longer than the maximum discharge length when the discharge range is maximum,
Forming a test pattern for detecting the amount of movement of the first belt, which is the amount of movement of the transport belt when the drive roller is rotated halfway,
A discharge range setting method, characterized in that, based on the test pattern, a discharge length, which is a length of the discharge range in the transport direction, is set to an integral multiple of the first belt movement amount.

Images