Inkjet drawing device

Abstract

To suppress a drawing failure attributed to the inclination of a head without mechanically adjusting the inclination of the head.SOLUTION: An inkjet drawing device includes a stage on which a recording medium can be placed, which can be moved in a Y axis direction; a carriage on which a head having a nozzle array can be mounted, which can be moved in an X-axis direction; and a control part for causing ink to be discharged from the nozzle array according to image data showing an image to be formed, and performing drawing on the recording medium. The control part causes a relative conveyance direction of the recording medium with respect to the carriage to be inclined in an XY plane according to the inclination of the head in the XY plane.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an inkjet drawing apparatus.

Background Art

[0002] There is known an inkjet drawing apparatus that moves a stage on which a recording medium is placed in a sub-scanning direction (hereinafter also referred to as the Y-axis direction), and ejects ink from nozzles of a head that can move in a main scanning direction (hereinafter also referred to as the X-axis direction) above the stage onto the recording medium. In such an inkjet drawing apparatus, in order to prevent the occurrence of image defects and the accompanying downtime, it is required to appropriately adjust the posture of the recording medium placed on the stage and the posture of the head. For example, a conventional inkjet recording apparatus described in Patent Document 1 corrects the inclination of the head by rotating the carriage of the head.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above conventional inkjet recording apparatus, a correction mechanism for mechanically displacing (rotating) the carriage of the head is required for correcting the inclination of the head. However, performing the mechanical adjustment of the carriage itself causes downtime. In addition, there is a problem that the configuration becomes complicated by adding a configuration for mechanical adjustment.

[0005] An object of the present invention is to provide an inkjet drawing apparatus capable of suppressing drawing defects caused by the inclination of the head without mechanically adjusting the inclination of the head.

Means for Solving the Problems

[0006] One aspect of the inkjet drawing apparatus according to the present invention is a stage on which a recording medium can be placed and that is movable in the Y-axis direction, a carriage that is attachable with a head having a nozzle array and that is movable in the X-axis direction, and a control unit that discharges ink from the nozzle array according to image data indicating an image to be formed and draws on the recording medium, wherein the control unit inclines the relative conveyance direction of the recording medium with respect to the carriage in the XY plane according to the inclination of the head in the XY plane.

Effect of the Invention

[0007] According to the present invention, it is possible to suppress drawing defects even when there is an inclination of the head or an inclination of the recording medium without complicating the configuration of the entire apparatus.

Brief Description of the Drawings

[0008]

Figure 1

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Figure 4

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Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, this embodiment will be described with reference to the drawings. In this embodiment, the X-axis direction is the main scanning direction and is the left-right direction. One side in the X-axis direction is the right direction, and the other side in the X-axis direction is the left direction. The Y-axis direction is the sub-scanning direction and is the front-rear direction. One side in the Y-axis direction is the front direction, and the other side in the Y-axis direction is the rear direction. The Y-axis direction is also the conveyance direction. When the Y-axis direction is regarded as the conveyance direction, the front direction is the forward direction of the conveyance direction, and the rear direction is the reverse direction of the conveyance direction.

[0010] With reference to FIGS. 1 to 3, the configuration of the inkjet drawing apparatus 10 according to this embodiment will be described. FIG. 1 is a schematic diagram showing the configuration of the inkjet drawing apparatus 10 as viewed from above. FIG. 2 is a cross-sectional view taken along the line II-II of the inkjet drawing apparatus 10 shown in FIG. 1. FIG. 3 is a block diagram showing the control system of the inkjet drawing apparatus 10.

[0011] The inkjet drawing device 10 is a drawing device that performs drawing on a recording medium M by discharging ink toward the recording medium M while conveying the recording medium M, such as a printed circuit board, in the Y-axis direction. The ink used in the inkjet drawing device 10 is a radical polymerizable ink containing a thermosetting substance and a gelling agent among the active energy ray curable types. The ink used in the inkjet drawing device 10 is an ultraviolet curable gel ink (hereinafter referred to as UV gel ink) among the radical polymerizable inks. When the recording medium M is a printed circuit board, a suitable example of the ink is a solder resist ink. The inkjet drawing device 10 may use other active energy ray curable inks, such as electron beam curable gel ink, instead of the UV gel ink.

[0012] The inkjet drawing device 10 includes a base 12, and the base 12 extends in the X-axis direction and the Y-axis direction. The longitudinal direction of the base 12 is the Y-axis direction, and the short-side direction of the base 12 is the X-axis direction. Also, a pair of Y-axis guide rails 14 extending in the Y-axis direction are provided in parallel on the right part (a part on one side in the X-axis direction) of the base 12. A transport stage 16 for placing the recording medium M and transporting it in the Y-axis direction (sub-scanning direction) is provided movably in the Y-axis direction on the pair of Y-axis guide rails 14. In other words, on the right part of the base 12, the transport stage 16 is provided movably in the Y-axis direction via the pair of Y-axis guide rails 14. The transport stage 16 may have a suction mechanism (not shown) for sucking the recording medium M. The transport stage 16 may have holding claws (not shown) for holding the end of the recording medium M.

[0013] At an appropriate position of the base 12, a Y-axis motor 18 is provided as a stage moving unit that moves the transport stage 16 in the Y-axis direction (sub-scanning direction). The output shaft (not shown) of the Y-axis motor 18 is linked to a part of the transport stage 16 via, for example, a ball screw mechanism (not shown) or a rack and pinion mechanism (not shown). The Y-axis motor 18 has a Y-axis encoder (not shown) as a first position detector that detects the position of the transport stage 16 in the Y-axis direction. The Y-axis encoder detects the position of the recording medium M placed on the transport stage 16 in the Y-axis direction in addition to the position of the transport stage 16 in the Y-axis direction.

[0014] At the central portion of the base 12 in the Y-axis direction, a gantry frame 22 extending in the X-axis direction is erected so as to straddle a pair of Y-axis guide rails 14. The gantry frame 22 has a pair of vertical portions 22a erected at a distance from each other in the X-axis direction at the central portion of the base 12 in the Y-axis direction, and a horizontal portion 22b connecting the upper end portions of one vertical portion 22a and the other vertical portion 22a and extending in the X-axis direction. In addition, a pair of X-axis guide rails 24 extending in the X-axis direction are provided in parallel on the horizontal portion 22b of the gantry frame 22. A carriage 26 is provided movably in the X-axis direction on the pair of X-axis guide rails 24. In other words, on the horizontal portion 22b of the gantry frame 22, the carriage 26 is provided movably in the X-axis direction via a pair of X-axis guide rails 24.

[0015] At an appropriate position of the horizontal portion 22b of the gantry frame 22, an X-axis motor 28 is provided as a carriage moving unit for moving the carriage 26 in the X-axis direction (main scanning direction). The output shaft (not shown) of the X-axis motor 28 is linked to a part of the carriage 26 via, for example, a ball screw mechanism (not shown) or a rack and pinion mechanism (not shown). The X-axis motor 28 has an X-axis encoder (not shown) as a second position detector that detects the position of the carriage 26 in the X-axis direction.

[0016] The carriage 26 is equipped with a head 32 for ejecting UV gel ink onto the recording medium M from above and printing. In other words, on the horizontal portion 22b of the portal frame 22, the head 32 is provided so as to be movable in the X-axis direction via the carriage 26. The head 32 has a plurality of nozzles 34 forming a nozzle row for ejecting UV gel ink on its lower side. The head 32 can be removed from the carriage 26 and replaced with a new head 32.

[0017] The carriage 26 is further provided with an irradiator 38. The irradiator 38 has a light source (not shown) that irradiates ultraviolet rays, which are an example of active energy rays, downward. The ultraviolet rays irradiated downward from the irradiator 38 cure the UV gel ink forming an image on the recording medium M. The light source is a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, a black light, a cold cathode tube, or an LED (Light Emitting Diode), etc.

[0018] In addition, when the ink to be used is cured by irradiation with active energy rays other than ultraviolet rays, the irradiator 38 is configured to irradiate active energy rays other than ultraviolet rays.

[0019] The carriage 26 is provided with an imaging unit 42, which is, for example, a camera. The imaging unit 42 is arranged to image a field of view that spreads downward. The imaging unit 42 can capture a test image or capture the recording medium M on the conveyance stage 16. Since the imaging unit 42 is provided on the carriage 26, it can move coaxially with the head 32, that is, it can move in the X-axis direction together. Since the imaging unit 42 and the head 32 are coaxial, the repetitive accuracy regarding the measurement of the deviation width described later can be improved.

[0020] As shown in FIGS. 1 and 2, the carriage 26 is movable in the X-axis direction (main scanning direction) between a drawing position where drawing is performed and a retracted position (the position shown by the solid line in FIGS. 1 and 2) retracted from the drawing position. The X-axis motor 28 has a function as a carriage moving unit for moving the carriage 26 in the X-axis direction, and in addition, has a function as a head moving unit for moving the head 32 in the X-axis direction between the printing position PP and the retracted position SP. The X-axis encoder 30 as a second position detector detects the position of the carriage 26 in the X-axis direction and also detects the position of the head 32 in the X-axis direction. In the retracted position, maintenance of the carriage 26, for example, flushing of the head 32 can be performed.

[0021] Note that in the present embodiment, the carriage 26 is movable in the X-axis direction among the drawing positions, for example, in the case of multi-pass drawing. Also, regardless of whether it is multi-pass drawing or single-pass drawing, the carriage 26 can perform drawing while moving in the X-axis direction. When performing drawing while moving the carriage 26 in the X-axis direction, it is possible to absorb the inclination of the head 32 and suppress the occurrence of drawing defects. This will be described in detail later.

[0022] Incidentally, a manifold (not shown) is provided in the head 32, and a common ink chamber (not shown) for storing UV gel ink is formed in the manifold. A supply port (not shown) for supplying UV gel ink to the common ink chamber is provided on one side of the head 32. A discharge port (not shown) for discharging UV gel ink from the supply ink chamber is provided on the other side of the head 32.

[0023] A plurality of pressure chambers (not shown) are provided for each nozzle 34 below the manifold in the head 32, and each pressure chamber communicates with the common ink chamber and the corresponding nozzle 34. Each pressure chamber is configured to be pressurized by the drive of a drive element such as a piezo element or a heating element. Each nozzle 34 is configured to eject (inject) UV gel ink when the corresponding pressure chamber is pressurized.

[0024] Therefore, each nozzle 34 can eject the UV gel ink in a heated state. When the heated UV gel ink lands on the recording medium M, the UV gel ink gels, and thereby, the UV gel ink is pinned on the recording medium M. As a result, the ink droplets are less likely to be displaced during drawing, and thus, the image quality can be improved.

[0025] The control unit 44 controls the operations of the Y-axis motor 18, the X-axis motor 28, the inkjet head 32, and the irradiator 38. The above-described Y-axis encoder and X-axis encoder are connected to the control unit 44. The control unit 44 includes a CPU (Central Processing Unit) 46, a ROM (Read Only Memory) 48, and a RAM (Random Access Memory) 50. Various processing programs are stored in the ROM 48. The CPU 46 reads out the various programs stored in the ROM 48 and expands them in the RAM 50, and controls a series of operations of the inkjet drawing apparatus 10 according to the expanded programs. A series of operations of the inkjet drawing apparatus 10 is, for example, the inclination correction drawing method described later. Note that the control unit 44 may be configured to be communicable with the outside so that various programs can be downloaded from the outside to the control unit 44 via a communication network. The ROM 48 is an example of a non-transitory and computer-readable storage medium.

[0026] Incidentally, the head 32 mounted on the carriage 26 may be inclined with respect to the X-axis direction. Typically, such an inclination occurs when the head 32 is replaced. Specifically, the inclination of the head 32 means that the nozzle row of the head 32 that should extend along the X-axis direction when normal may be oblique with respect to the X-axis direction. When drawing is performed with such an inclination of the head 32, drawing defects are likely to occur, so it is desirable to correct the inclination before drawing. However, physically adjusting the orientation of the head 32 or the carriage 26 on which the head 32 is mounted as described above makes it difficult to reduce downtime. In addition, if a mechanical configuration for such adjustment is added, the configuration of the entire apparatus becomes complicated and the cost may increase.

[0027] Also, the recording medium M, which is the object to be drawn, may be inclined when placed on the transport stage 16. The inclination of the recording medium M here refers to the inclination with respect to the image of the drawing object shown in the image data. When drawing is performed with such an inclination of the recording medium M, drawing defects are likely to occur, so it is desirable to correct the inclination before drawing. However, as described above, physically adjusting the orientation of the recording medium M or the transport stage 16 on which the recording medium M is placed also makes it difficult to reduce downtime. In addition, the configuration of the entire apparatus becomes complicated and the cost may increase.

[0028] Regarding this point, in the present embodiment, by the inclination correction drawing method described below, it is possible to suppress drawing defects even when the head is inclined and the recording medium is inclined without complicating the configuration of the entire inkjet drawing apparatus 10.

[0029] Hereinafter, the inclination correction drawing method executed in the inkjet drawing apparatus 10 will be described. FIG. 4 is a flowchart for explaining the inclination correction drawing method. The control subject of the inclination correction drawing method is the control unit 44. Under the control of the control unit 44, each part in the inkjet drawing apparatus 10 operates to realize inclination correction drawing.

[0030] In step S101, it is confirmed whether adjustment of the head 32 is necessary. For example, when the head 32 is replaced with a new one and the user wants to perform drawing after eliminating the inclination of the head 32, adjustment of the head 32 is necessary. In such a case, the user can input a command for executing the adjustment of the head 32 or the like via an input unit (not shown) such as a keyboard provided in the inkjet drawing apparatus 10. According to the input comment, the control unit 44 determines the necessity of adjusting the head 32.

[0031] If adjustment of the head 32 is necessary (YES in step S101), the process proceeds to step S102. If adjustment of the head 32 is not necessary (NO in step S101), the process proceeds to step S105.

[0032] In step S102, a test image is drawn on a test recording medium (not shown). When drawing the test image, while moving the transport stage 16 on which the test recording medium is placed in the Y-axis direction, the position of the head 32 (carriage 26) is fixed in the X-axis direction.

[0033] An example of the test image is as shown in FIG. 5A. In the example shown here, the head 32 employs a multi-nozzle configuration having four nozzle rows extending in the X-axis direction. In this configuration, ink is ejected from the nozzles 34 (ejection nozzles) belonging to the sub-arrays #1 and #2, and ink is not ejected from the nozzles 34 (non-ejection nozzles) belonging to the sub-arrays #3 and #4. In this way, non-ejection nozzles are interposed between the ejection nozzles in the X-axis direction. As a result, the dots (in FIG. 5A, the dots are connected to form a line) constituting the test image are separated in the X-axis direction. Since the position (or interval) of this dot (or line) changes according to the inclination of the head 32, the inclination of the head 32 can be detected by capturing this change.

[0034] When the head 32 has no inclination, the separation distance from the mounting reference position of a predetermined nozzle 34 in the X-axis direction (the positioning reference position when the head 32 is mounted on the carriage 26) is defined as the distance La (see FIG. 5A). Further, when the head 32 has no inclination, the angle formed by the straight line connecting the position of the predetermined nozzle 34 and the mounting reference position with the X-axis direction is defined as the angle θa (see FIG. 5A).

[0035] In step S103, the imaging unit 42 captures the drawn test image.

[0036] Then, in step S104, the control unit 44 measures the deviation width (the distance L1 (absolute value) of the displacement from the normal position) of the predetermined nozzle 34 in the X-axis direction based on the position of the line in the captured test image. Then, the control unit 44 calculates the inclination θ1 of the head 32 using the following (Equation 1).

[0037] θ1 = arccos((La - L1) / La) * (180 / π) ···(Equation 1)

[0038] When the head 32 inclines in the clockwise direction, the line of the predetermined nozzle 34 shifts in the direction approaching the mounting reference position (the right direction as shown in FIG. 5B). In this case, the inclination θ1 becomes a positive value. When the head 32 inclines in the counterclockwise direction, the line of the predetermined nozzle 34 shifts in the direction moving away from the mounting reference position (the left direction as shown in FIG. 5C). In this case, the inclination θ1 becomes a negative value.

[0039] In step S105, with the recording medium M, which is the object to be drawn, placed on the conveyance stage 16, the imaging unit 42 captures the reference position of the recording medium M.

[0040] An example of the reference position of the recording medium M is specified by alignment marks formed on the recording medium M (in the example shown here, two alignment marks #1 and #2 at the front left position and the rear right position of the recording medium M), as shown in FIG. 6A. Note that, for example, when through holes are provided in the recording medium M, the through holes may be used as the reference position of the recording medium M.

[0041] When the recording medium M has no inclination, the separation distance between two alignment marks #1 and #2 in the X-axis direction is defined as the distance Lbx. Further, when the recording medium M has no inclination, the separation distance between two alignment marks #1 and #2 in the Y-axis direction is defined as the distance Lby.

[0042] In step S106, the control unit 44 detects the alignment marks #1 and #2 in the captured image of the recording medium M. Then, the control unit 44 measures the displacement width (the distances L2x and L2y of displacement from the normal position) of the position of the alignment mark #2 with respect to the alignment mark #1. Note that the distance L2x is the displacement width in the X-axis direction, and the distance L2y is the displacement width in the Y-axis direction. Then, the control unit 44 calculates the inclination θ2 of the recording medium M using the following (Equation 2).

[0043] θ2 = arctan(L2x / L2y) * (180 / π) ···(Equation 2)

[0044] When the recording medium M is inclined in the clockwise direction, the alignment mark #2 is displaced with respect to the alignment mark #1 in a direction approaching on the X-axis and a direction moving away on the Y-axis (see FIG. 6B). In this case, the values of the distances L2x and L2y are positive values, and the inclination θ2 is a positive value. When the recording medium M is inclined in the counterclockwise direction, the alignment mark #2 is displaced with respect to the alignment mark #1 in a direction moving away on the X-axis and a direction approaching on the Y-axis (see FIG. 6C). In this case, the values of the distances L2x and L2y are negative values, and the inclination θ2 is a negative value.

[0045] In step S107, the control unit 44 calculates X-axis drive conditions and Y-axis drive conditions based on the calculated inclination θ1 of the head 32 and the inclination θ2 of the recording medium M. The X-axis drive conditions include the moving speed (X-axis direction speed) Vx of the head 32 (carriage 26) on the X-axis. The Y-axis drive conditions include the moving speed (Y-axis direction speed) Vy of the recording medium M (transport stage 16) on the Y-axis.

[0046] Here, for example, as shown in FIG. 7, it is assumed that both the inclination θ1 of the head 32 and the inclination θ2 of the recording medium M occur. In such a situation, the control unit 44 refers to the inclination θ1 of the head 32 in calculating the X-axis drive condition and the Y-axis drive condition.

[0047] Specifically, the control unit 44 causes the relative conveyance direction of the recording medium M with respect to the carriage 26 to form an inclination angle θ1 corresponding to the inclination θ1 of the head 32 with respect to the Y-axis direction. Actually, since the recording medium M and the conveyance stage 16 cannot move in the X-axis direction, the control unit 44 may move the head 32 and the carriage 26 in the X-axis direction. For example, when the Y-axis direction speed Vy is fixedly set to a predetermined speed, the control unit 44 may only vary the X-axis direction speed Vx of the head 32 and the carriage 26. When the direction of the relative conveyance direction speed Vf obtained by synthesizing the X-axis direction speed Vx and the Y-axis direction speed Vy forms an inclination angle θ1 with respect to the Y-axis direction, the relative conveyance direction of the recording medium M and the conveyance stage 16 with respect to the head 32 and the carriage 26 is inclined by an angle θ1 with respect to the Y-axis direction. Alternatively, the control unit 44 may first set the relative conveyance direction speed Vf, and then calculate the X-axis direction speed Vx and the Y-axis direction speed Vy using the following (Equation 3) and (Equation 4) respectively (see FIG. 8).

[0048] Vx = Vf * sin θ1 ···(Equation 3) Vy = Vf * cos θ1 ···(Equation 4)

[0049] By performing the inclined conveyance of the recording medium M and the conveyance stage 16 with respect to the head 32 and the carriage 26, the inclination θ1 of the head 32 is absorbed, so that drawing defects caused by the inclination θ1 of the head 32 can be suppressed. Moreover, it is not necessary to mechanically adjust the orientation of the carriage 26 for inclination correction of the head 32. Therefore, the occurrence of downtime associated with mechanical adjustment can be suppressed. Also, complication of the entire inkjet drawing apparatus 10 can be avoided.

[0050] As long as the inclination angle θ1 of the relative conveyance direction can be adjusted to match the inclination θ1 of the head 32, not only the X-axis direction speed Vx but also the Y-axis direction speed Vy may be made variable.

[0051] The control unit 44 applies (sets) the X-axis drive condition and the Y-axis drive condition including the calculated X-axis direction speed Vx and Y-axis direction speed Vy, respectively.

[0052] In step S108, the control unit 44 performs rotation correction on the image data of the drawing target. For example, assume that the drawing target image shown in the image data is a rectangular image having two pairs of opposite sides parallel to the X-axis direction and the Y-axis direction, respectively (see FIG. 9A). This image is an image to be formed on the recording medium M in a non-inclined state.

[0053] When the recording medium M is inclined by an angle θ2, the control unit 44 corrects the image data so as to rotate the target image by an angle θ2. For example, as shown in FIG. 9B, the position of the left front corner of the target image is fixed, and the other parts of the target image are inclined by an angle corresponding to the inclination θ2 of the recording medium M by rotation. As a result, the inclination θ2 of the recording medium M is absorbed, so that drawing defects caused by the inclination θ2 of the recording medium M can be suppressed. Moreover, it is not necessary to physically adjust the orientation of the recording medium M or the conveyance stage 16 for inclination correction of the recording medium M. Therefore, the occurrence of downtime can be suppressed. In addition, since a special mechanical configuration for adjusting the orientation of the recording medium M or the conveyance stage 16 is not required, complication of the entire inkjet drawing apparatus 10 can also be avoided.

[0054] In step S109, the control unit 44 calculates the path division of the drawing pattern.

[0055] For example, as shown in FIG. 10A, when both the head 32 and the recording medium M are in their normal positions and there is no inclination in the conveyance of the recording medium M nor rotation correction of the target image, it is assumed that the drawable range that can be covered in two passes exactly matches the range of the target image. In such a case, if an inclination occurs in at least one of the head 32 and the recording medium M, there is a risk that the range of the target image cannot be covered in two passes. Therefore, in step S109, based on the inclination of the relative conveyance direction according to the inclination θ1 of the head 32 and the rotation correction of the target image according to the inclination θ2 of the recording medium M, the path division of the drawing pattern is calculated and set. In the example shown in FIG. 10B, it is shown that when the number of path divisions is three, the range of the target image is covered. Thus, in this example, by increasing the number of path divisions by only one compared to the case where both the head 32 and the recording medium M are in their normal positions, it is possible to perform the drawing of the target image on the recording medium M.

[0056] In step S110, the control unit 44 moves the carriage 26 and the conveyance stage 16 for three passes under the set X-axis drive conditions and Y-axis drive conditions, and executes the drawing on the recording medium M according to the rotation-corrected target image data.

[0057] As described above, according to the present embodiment, the inkjet drawing apparatus 10 can mount the recording medium M, and can mount the head 32 having an array of nozzles 34, and has a carriage 26 movable in the X-axis direction, and a control unit 44 that discharges ink from the array of nozzles 34 according to the image data indicating the image to be formed and performs drawing on the recording medium M. The control unit 44 inclines the relative conveyance direction of the recording medium M with respect to the carriage 26 in the XY plane according to the inclination θ1 of the head 32 in the XY plane.

[0058] Thus, even if the head 32 has an inclination θ1, by inclining the relative conveyance direction by the inclination angle θ1 with respect to the Y-axis direction, the inclination θ1 of the head 32 is absorbed, so that drawing defects caused by the inclination θ1 of the head 32 can be suppressed. Moreover, it is not necessary to mechanically adjust the orientation of the carriage 26 for inclination correction of the head 32. Therefore, the occurrence of downtime can be suppressed, and complication of the entire inkjet drawing apparatus 10 can be avoided.

[0059] Further, according to the present embodiment, the control unit 44 rotates and inclines the drawing target image shown in the image data in the XY plane by an angle corresponding to the inclination θ2 of the recording medium M in the XY plane.

[0060] Thus, even if the recording medium M has an inclination θ2, by rotating the drawing target image by an angle corresponding to the inclination θ2, the inclination θ2 of the recording medium M is absorbed, so that drawing defects caused by the inclination θ2 of the recording medium M can be suppressed. Moreover, it is not necessary to physically adjust the orientation of the recording medium M or the conveyance stage 16. Therefore, the occurrence of downtime can be suppressed, and complication of the entire inkjet drawing apparatus 10 can be avoided.

[0061] As described above, the embodiments of the present invention have been specifically described, but the present invention is not limited to the specific embodiments described above. Various modifications and changes can be made to the specific examples described in the above embodiments within the scope of the gist of the present invention described in the claims.

Industrial Applicability

[0062] The present invention can be suitably used in an inkjet drawing apparatus.

Explanation of Signs

[0063] 10 Inkjet drawing apparatus 12 Base 14 Y-axis guide rail 16 Conveyance stage 18 Y-axis motor 22 Gate-Type Frame 22a Vertical Portion 22b Horizontal Portion 24 X-Axis Guide Rail 26 Carriage 28 X-Axis Motor 32 Head 34 Nozzle 38 Irradiator 44 Control Unit 46 CPU 48 ROM 50 RAM M Recording Medium

Claims

1. A stage on which a recording medium can be placed and is movable in the Y-axis direction, A carriage on which a head having a nozzle array can be mounted and is movable in the X-axis direction, A control unit that discharges ink from the nozzle array according to image data indicating an image to be formed and draws on the recording medium, and has: The control unit inclines the relative conveyance direction of the recording medium with respect to the carriage in the XY plane according to the inclination of the head in the XY plane. An inkjet drawing apparatus.

2. The control unit sets the moving speed of the carriage in the X-axis direction and the moving speed of the stage in the Y-axis direction so that the relative conveyance direction of the recording medium has an inclination angle corresponding to the inclination of the head with respect to the Y-axis direction. The inkjet drawing apparatus according to Claim 1.

3. The control unit inclines the image to be formed of the image data in the XY plane according to the inclination of the recording medium in the XY plane. The inkjet drawing apparatus according to Claim 1.

4. Further having a camera, The control unit detects a reference position of the recording medium on the stage photographed by the camera and calculates the inclination of the recording medium. The inkjet drawing apparatus according to Claim 1.

5. The camera is movable in the X-axis direction together with the head. The inkjet drawing apparatus according to Claim 4.

6. The control unit interposes at least one non-discharge nozzle that does not discharge ink during the drawing of the test image between discharge nozzles that discharge ink during the drawing of the test image, and separates dots of the test image in the X-axis direction. The inkjet drawing apparatus according to Claim 1.

7. The recording medium is a printed circuit board, The ink is solder resist ink. The inkjet drawing apparatus according to Claim 1.

8. The ink contains a gel, The control unit discharges the ink in a heated state and pins the ink on the recording medium by gelation of the ink due to landing of the ink on the recording medium. The inkjet drawing apparatus according to Claim 1.

Images