Inkjet apparatus

Abstract

To perform alignment between a plurality of heads with a simpler configuration.SOLUTION: The inkjet device 1 includes a head unit 32 having a plurality of heads 33 for ejecting ink to a substrate W1 placed on a stage 22, and applies the ink to the substrate W1 by landing the ink at a predetermined position of the substrate W1 moving relative to the head unit 32, wherein the inkjet device 1 includes a plurality of motors 51 for changing relative positions of nozzles 35 between the plurality of heads 33 in the head unit 32 by respectively moving the plurality of heads 33, a servo amplifier 42 for outputting an operation command to the motors 51, and a circuit unit 43 for switching electrical connection states of the plurality of motors 51 and the servo amplifiers 42. The circuit unit 43 is switchable from a first state in which the operation command of the servo amplifier 42 is output to the first motor 51a among the plurality of motors 51 to a second state in which the operation command of the servo amplifier 42 is output to the second motor 51b different from the first motor 51a among the plurality of motors 51.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an inkjet device. [Background technology]

[0002] It is known to use inkjet technology to manufacture devices such as color filters. In order to obtain the desired quality during device manufacturing, it is required to maintain high accuracy in the ink application position.

[0003] For example, the inkjet coating device of Patent Document 1 ejects R (red), G (green), and B (blue) inks onto a substrate to manufacture color filters used in flat panel displays such as color liquid crystal displays. In Patent Document 1, the amount of deformation of the head case due to thermal expansion is measured, and based on this, deviations in the ejection position are corrected in order to ensure that the ink hits specific pixels on the substrate with high precision.

[0004] Patent Document 2 discloses a technique for providing a head moving means (piezoelectric element) that displaces each of the Y, M, and C heads, separate from the carriage reciprocating mechanism, in order to perform appropriate overprinting in an inkjet printer. In Patent Document 2, Y, M, and C are test printed on recording paper, and the heads are displaced by the head moving means by the amount of deviation of the print dots, thereby aligning the multiple heads. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-215173 [Patent Document 2] Japanese Patent Application Publication No. 5-301353 Summary of the Invention [Problem to be solved by the invention]

[0006] When ejecting ink onto a large substrate, a head unit that integrates multiple heads may be used. Patent Document 1 shows an example in which 24 or more head units are attached to a single head case.

[0007] Patent Document 2 discloses three head moving means for moving three heads, respectively. However, to align more heads (for example, 24 or more), a control mechanism for each head is required, which makes the alignment mechanism more complicated.

[0008] In view of the above-described conventional problems, an object of the present disclosure is to provide an inkjet device that can align multiple heads with a simpler configuration. [Means for solving the problem]

[0009] The inkjet device of the present invention is an inkjet device that includes a head unit having a plurality of heads that eject ink onto a substrate placed on a stage, and applies ink to the substrate by landing ink at a predetermined position on the substrate that moves relative to the head unit, and is equipped with a plurality of motors that change the relative positions of nozzles between the plurality of heads within the head unit by moving each of the plurality of heads, a servo amplifier that outputs operation commands to the motors, and a circuit unit that switches the electrical connection state between the plurality of motors and the servo amplifier, and the circuit unit is switchable from a first state in which the servo amplifier outputs an operation command to a first motor of the plurality of motors, to a second state in which the servo amplifier outputs an operation command to a second motor of the plurality of motors that is different from the first motor. [Effects of the Invention]

[0010] According to the inkjet device of the present invention, it is possible to align a plurality of heads with a simpler configuration. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a front view schematically illustrating an inkjet device according to an embodiment. [Figure 2] FIG. 1 is a plan view schematically illustrating an inkjet device according to an embodiment. [Figure 3] FIG. 2 is a schematic diagram illustrating the configuration of a head. [Figure 4] 5A and 5B are schematic diagrams illustrating movement of a nozzle surface by a drive mechanism. [Figure 5] FIG. 2 is a block diagram illustrating a schematic functional configuration of the inkjet device. [Figure 6] FIG. 2 is a block diagram schematically illustrating the internal configuration of a circuit unit. [Figure 7] FIG. 10 is a block diagram schematically illustrating a partial functional configuration of an inkjet device according to a modified example. [Figure 8] 10A and 10B are explanatory diagrams of the nozzle adjustment process of this modified example. [Figure 9] FIG. 10 is a plan view schematically showing an inkjet device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Outline of the embodiment of the present invention> Hereinafter, an outline of an embodiment of the present invention will be listed and described.

[0013] (1) The inkjet device of the present invention is an inkjet device that includes a head unit having a plurality of heads that eject ink onto a substrate placed on a stage, and applies ink to the substrate by landing ink at a predetermined position on the substrate that moves relative to the head unit, and includes a plurality of motors that change the relative positions of nozzles between the plurality of heads within the head unit by moving each of the plurality of heads, a servo amplifier that outputs operation commands to the motors, and a circuit unit that switches the electrical connection state between the plurality of motors and the servo amplifier, and the circuit unit is switchable from a first state in which the operation command of the servo amplifier is output to a first motor of the plurality of motors, to a second state in which the operation command of the servo amplifier is output to a second motor of the plurality of motors that is different from the first motor.

[0014] Because the circuit unit can transition from a first state in which it outputs an operation command to a first motor of the multiple motors to a second state in which it outputs an operation command to a second motor of the multiple motors, it is possible to associate the servo amplifiers with the multiple motors in a one-to-many relationship. This reduces the number of servo amplifiers that were previously required for each of the multiple motors, allowing for alignment between multiple heads with a simpler configuration.

[0015] (2) The inkjet device of (1) above may further include a plurality of brakes that fix the positions of the plurality of heads, respectively, and the plurality of brakes may fix the positions of the heads that are moved by the motor and are not connected to the servo amplifier by the circuit unit.

[0016] With this configuration, the brake can suppress unexpected movement of the head that occurs when a servo amplifier and a plurality of motors are associated in a one-to-many relationship, and the head can be positioned in an appropriate location.

[0017] (3) In the inkjet device of (2) above, the brake includes a negatively acting brake that releases the head when energized and fixes the head when de-energized, and the negatively acting brake may be energized from a power line that inputs an operation command from the servo amplifier to the motor.

[0018] With this configuration, it is possible, with a simple configuration, to turn off the brake when the motor corresponding to the same head is on, and turn on the brake when the motor is off.

[0019] (4) The inkjet device of (2) above may further include a control unit that controls the circuit unit, the plurality of heads, and the plurality of brakes, and the control unit may perform position adjustment control to move the head by the first motor while the head moved by the first motor in the first state is being braked by the brake, and switching control to switch the circuit unit from the first state to the second state after the position adjustment control.

[0020] With this configuration, the head is moved to the commanded position by the motor while the brake is applied. Therefore, when the position adjustment by the motor is completed, the brake is already applied, and it is possible to prevent the head from accidentally shifting position when the motor is switched off. As a result, the head can be positioned to the commanded position with higher accuracy.

[0021] (5) In the inkjet device of (1) to (4) above, the device is provided with a plurality of servo amplifiers, including a first servo amplifier that sequentially outputs operation commands to a plurality of the motors belonging to a first group, and a second servo amplifier that sequentially outputs operation commands to a plurality of the motors belonging to a second group different from the first group, and the first group and the second group are groups in which the plurality of the motors are grouped according to the rows or columns in which the heads moved by the motors are arranged, or according to the movement axis of the heads moved by the motors.

[0022] <Details of the embodiment of the present invention> Hereinafter, the details of the embodiments of the present invention will be described.

[0023] [Overall configuration of inkjet device 1] FIG. 1 is a front view schematically showing an inkjet device 1 according to an embodiment. 2 is a plan view that schematically shows the inkjet device 1. For the sake of explanation, each of the following figures shows an XYZ Cartesian coordinate system in the figure, where the XY plane is the horizontal plane and the Z axis is the vertical axis.

[0024] The inkjet device 1 includes a stage unit 2, a coating unit 3, and a control unit 4. The inkjet device 1 manufactures color filters used in flat panel displays such as color liquid crystal displays.

[0025] The stage unit 2 has a base 21, a substrate stage 22 provided on the base 21, and a movement mechanism 23 that moves the substrate stage 22 in a horizontal direction. The substrate stage 22 places the substrate W1 in a horizontal position. The substrate stage 22 may hold the back surface of the substrate W1 (the surface that does not face the head 33) by vacuum suction, or may grip the periphery of the substrate W1 with pins. The substrate W1 is, for example, a glass substrate or a resin substrate that is transparent to visible light.

[0026] The moving mechanism 23 is, for example, a linear motor, and moves the substrate stage 22 in the horizontal direction in accordance with a command signal from the control unit 4. Note that although the moving mechanism 23 in this embodiment moves the substrate stage 22 back and forth only in the Y direction, the moving mechanism 23 may also be capable of moving the substrate stage 22 in the X direction.

[0027] The coating unit 3 has two gantries 31 and a head unit 32. The two gantries 31 support the head unit 32 above the substrate stage 22. Each gantry 31 includes two legs 31a and a beam 31b that spans between the legs 31a. The head unit 32 is attached to the beam 31b.

[0028] 1 and 2, the gantry 31 included in the coating unit 3 may be a "double-supported" gantry that supports the head unit 32 at both ends in the Y direction, or a "cantilevered" gantry that supports the head unit 32 at only one end in the Y direction. In the latter case, the head unit 32 is supported by a single gantry 31.

[0029] The head unit 32 includes a plurality of heads 33. The plurality of heads 33 are fixed to the head unit 32 and aligned in the X direction by color. Hereinafter, when the plurality of heads 33 are particularly distinguished by row and column, the columns will be referred to as "column A," "column B," and "column C" in order from the negative side in the Y direction. For example, heads 33 that eject red ink are lined up in column A, heads 33 that eject green ink are lined up in column B, and heads 33 that eject blue ink are lined up in column C.

[0030] The rows are numbered in order from the positive side in the X direction in each column, such as "head A1," "head A2," ..., "head A6," etc. In the embodiment, 18 heads 33 in 3 columns and 6 rows are shown as an example, but the arrangement and number of heads 33 are not limited to this.

[0031] The inkjet device 1 applies ink of each color, such as R (red), G (green), or B (blue), to the substrate W1 by moving the substrate W1 placed on the substrate stage 22 in the direction indicated by the arrow AR1 in accordance with a command signal from the control unit 4 and causing ink ejected from the head 33 to land at predetermined positions on the substrate W1. Note that the substrate W1 only needs to move relative to the head unit 32, and for example, the application unit 3 may be configured to move horizontally relative to the stationary substrate W1.

[0032] [Configuration of head 33] Fig. 3 is a schematic diagram illustrating the configuration of the head 33. Fig. 3 shows the head 33 as a perspective view looking up from the bottom surface (nozzle surface 34) of the head 33.

[0033] The head 33 includes a nozzle surface 34 on which a plurality of nozzles 35 are aligned, and a drive mechanism 36 that changes the position of the nozzles 35 within the head unit 32. The head 33 is a piezoelectric inkjet head that mechanically ejects ink stored in a tank as minute droplets from the nozzles 35 using, for example, piezoelectric elements driven in accordance with command signals from the control unit 4. The ejection method of the head 33 is not particularly limited, and for example, the head 33 may be a thermal inkjet head that ejects ink from the nozzles 35 using bubbles generated by heating a heater.

[0034] The drive mechanism 36 includes units that are subdivided into axes that adjust the position of the nozzle surface 34, such as a θ-axis drive unit 361, an X-axis drive unit 362, and a Y-axis drive unit 363. Each of the units 361 to 363 includes a head stage 50, a motor 51, and a brake 52.

[0035] Specifically, the θ-axis drive unit 361 includes a head stage 501 that holds the nozzle surface 34, a motor 511 that moves the head stage 501 in the θ direction (the direction of rotation around the vertical axis in a horizontal plane), and a brake 521 that fixes the head stage 501 in the θ direction.

[0036] For example, while the motor 511 is ON, the position of the head stage 501 in the θ direction is adjusted by the motor 511. On the other hand, when the motor 511 is turned OFF, the head stage 501 can move freely in the θ direction. In this case, by fixing the head stage 501 with the brake 521, the movement of the head stage 501 in the θ direction can be restricted.

[0037] Furthermore, X-axis drive unit 362 includes a head stage 502 that holds head stage 501, a motor 512 that moves head stage 502 in the X direction, and a brake 522 that fixes head stage 502 in the X direction. Similarly, Y-axis drive unit 363 includes a head stage 503 that holds head stage 502, a motor 513 that moves head stage 503 in the Y direction, and a brake 523 that fixes head stage 503 in the Y direction.

[0038] These head stages 501 to 503 will be referred to as "head stages 50" unless otherwise specified. Similarly, the motors 511 to 513 and brakes 521 to 523 will be referred to as "motors 51" and "brakes 52" unless otherwise specified.

[0039] The motor 51 is, for example, a servo motor, and is driven in accordance with an operation command input from a servo amplifier 42, which will be described later. The type of the motor 51 is not particularly limited, and it may be, for example, a linear motor.

[0040] The brake 52 is a negative-acting brake, specifically a non-excitation brake, that releases the head 33 (more specifically, the head stage 50 of the head 33) when energized and locks the head 33 when de-energized. The brake 52 is energized from a power line L1 that inputs an operation command from a servo amplifier 42 (described later) to the motor 51. Therefore, when the power line L1 is energized and the motor 51 is turned ON, the brake 52 is turned OFF and the head 33 is unlocked.

[0041] The type of brake 52 is not particularly limited, and may be a positive acting brake (for example, an electromagnetic brake) that fixes the head 33 when energized. In addition, when the motor 51 is a linear motor, the brake 52 may be a clamper that is attached to a linear rail or the like.

[0042] As described above, the head 33 of this embodiment can be driven in three directions, the θ-axis, X-axis, and Y-axis, and each head 33 has three motors 51 and three brakes 52. However, the number of drivable axes is not limited to this, and for example, the head 33 may be capable of driving only the X-axis. In other words, the drive mechanism 36 only needs to have at least one unit selected from the θ-axis drive unit 361, the X-axis drive unit 362, and the Y-axis drive unit 363.

[0043] [Alignment between multiple heads 33] 4 is a schematic diagram illustrating movement of the nozzle surface 34 by the drive mechanism 36. The multiple motors 51 included in the drive mechanism 36 move each of the multiple heads 33 (more specifically, head stages 50 of the heads 33), thereby changing the relative positions of the nozzles 35 between the multiple heads 33 in the head unit 32. This makes it possible to correct the landing positions of ink on the substrate W1 between the multiple heads 33.

[0044] As an example of correction, for example, in the A1 head 33, if the ink landing position of the nozzles 35 on the substrate W1 is deviated from the landing position of another head 33 (for example, the B1 head 33), the nozzle surface 34 of the A1 head 33 is moved horizontally (for example, in the X and Y directions) by the drive mechanism 36 of the A1 head 33 to align the landing position of the A1 head 33 with the landing position of the other head 33. Similarly, if there is a deviation in the landing position of the C2 head 33, the nozzle surface 34 of the C2 head 33 is rotated, for example, in the θ direction, to align the landing position of the C2 head 33 with the landing position of the other head 33.

[0045] In this way, the inkjet device 1 of this embodiment can align the multiple heads 33 using the multiple motors 51. However, as described above, the inkjet device 1 has 18 heads 33, and each head 33 is provided with three motors 51, so the control unit 4 needs to control a total of 54 motors 51.

[0046] Conventionally, it is common to use servo amplifiers equal to the number of motors 51 to control each motor 51. However, with such a configuration, when there are a large number of motors 51 as described above, the number of servo amplifiers also increases, which creates a problem of the control unit 4 becoming more complex.

[0047] Therefore, in this embodiment, a circuit unit 43 is provided between the servo amplifier 42 and the motor 51, and the circuit unit 43 appropriately switches the motor 51 to which the servo amplifier 42 outputs an operation command, thereby allowing one servo amplifier 42 to sequentially control multiple motors 51. In this way, by associating servo amplifiers 42 with motors 51 in a one-to-multiple relationship, the number of servo amplifiers 42 can be reduced, and the control unit 4 can have a simpler configuration. The configuration of the control unit 4 will be described below.

[0048] [Functional configuration of inkjet device 1] 5 is a block diagram showing a schematic functional configuration of the inkjet device 1. The control unit 4 has a control unit 41, multiple servo amplifiers 42, multiple circuit sections 43, and a servo amplifier 44 for the substrate stage 22. When the multiple servo amplifiers 42 need to be distinguished, they will be referred to as a first servo amplifier 42a, a second servo amplifier 42b, etc., and when the multiple circuit sections 43 need to be distinguished, they will be referred to as a first circuit section 43a, a second circuit section 43b, etc. It is not necessary for the control unit 4 to include multiple servo amplifiers 42 and circuit sections 43; there may be only one of each.

[0049] The control unit 41 is a computer device that includes a processor such as a CPU (Central Processing Unit) and memories such as RAM (Random Access Memory), ROM (Read Only Memory) and HDD (hard disk drive), and generates command signals in response to user operations, etc., and outputs the command signals to each part of the inkjet device 1.

[0050] The servo amplifier 42 is an amplifier device that generates an operation command by amplifying a command signal to the drive mechanism 36 input from the control unit 41, and outputs the operation command to the drive mechanism 36 (specifically, the motor 51 and the brake 52). The servo amplifier 42 is electrically connected between the control unit 41 and the drive mechanism 36.

[0051] The circuit unit 43 is a switch device that switches the electrical connection state between the multiple drive mechanisms 36 and the servo amplifier 42. In the example of FIG. 6, the first circuit unit 43a is electrically connected between the first servo amplifier 42a and the multiple drive mechanisms 36a and 36b. The first circuit unit 43a is connected to the motor 51a and the brake 52a by a power supply line L1a, and the first circuit unit 43a is connected to the motor 51b and the brake 52b by a power supply line L1b. When there is no need to particularly distinguish between the power supply lines L1a and L1b that connect the circuit unit 43 to the multiple motors 51 and the multiple brakes 52, respectively, they will be simply referred to as the "power supply line L1."

[0052] The first circuit section 43a is switchable between a first state in which it outputs an operation command for the first servo amplifier 42a to the drive mechanism 36a, and a second state in which it outputs an operation command for the first servo amplifier 42a to the drive mechanism 36b.

[0053] The second circuit unit 43b is electrically connected between the second servo amplifier 42b and the plurality of drive mechanisms 36c, 36d. The second circuit unit 43b is switchable between a first state in which the second servo amplifier 42b outputs an operation command to the drive mechanism 36c, and a second state in which the second servo amplifier 42b outputs an operation command to the drive mechanism 36d.

[0054] Here, a set of multiple drive mechanisms 36a, 36b electrically connected to the first servo amplifier 42a and the first circuit unit 43a is referred to as a "first group G1." Similarly, a set of multiple drive mechanisms 36c, 36d electrically connected to the second servo amplifier 42b and the second circuit unit 43b is referred to as a "second group G2." The number of drive mechanisms 36 included in each of the first group G1 and the second group G2 may be three or more. Furthermore, when the control unit 4 includes three or more servo amplifiers 42, the number of groups may also be three or more.

[0055] The grouping of the heads 33 into groups is not particularly limited, and may be, for example, grouped by the rows in which the heads 33 are arranged in the head unit 32. In this case, for example, the heads 33 belonging to row A (head A1, head A2, ..., head A6) may be grouped into a first group G1, and the heads 33 belonging to row B (head B1, head B2, ..., head B3) may be grouped into a second group G2. By grouping the heads into rows of each color in this manner, the operation of the multiple drive mechanisms 36 can be controlled for each color. For example, when coating the substrate W1 using a manufacturing recipe that uses only red ink and no other colors of ink, only row A needs to be used, and therefore only the first servo amplifier 42a and the first circuit unit 43a need to be operated, and the second servo amplifier 42b and the second circuit unit 43b can be paused.

[0056] Furthermore, in the head unit 32, the heads 33 may be grouped by the rows in which they are arranged. In this case, for example, the heads belonging to the first row (head A1, head B1, head C1) may be grouped into a first group G1, and the heads belonging to the second row (head A2, head B2, head C2) may be grouped into a second group G2. Furthermore, the heads may be grouped by multiple rows, for example, the first and second rows may be grouped into the first group G1, and the third and fourth rows may be grouped into the second group G2. By grouping by row in this way, when the width of the substrate W1 in the X direction is narrower than the width of the head unit 32, the servo amplifiers 42 and the like belonging to the group not used for coating can be paused.

[0057] Furthermore, the head unit 32 may be grouped according to the movement axis of the head 33. For example, the θ-axis drive units 361 of each of the multiple heads 33 may be grouped into a first group G1, and the X-axis drive units 362 may be grouped into a second group G2.

[0058] FIG. 6 is a block diagram showing the internal configuration of the circuit section 43. As shown in FIG. The circuit section 43 is, for example, a circuit board having a plurality of switches 431, and has an input pin 432 to which an operation command for the servo amplifier 42 is input, a plurality of output pins 433 that output the operation command for the servo amplifier 42 to the drive mechanism 36 (specifically, the motor 51 and the brake 52), and a control pin 434 to which a command signal from the control section 41 is input.

[0059] For example, switch 431a switches the electrical connection between input pin 432 and output pin 433a between ON and OFF. When switch 431a is ON, an operation command input to input pin 432 is output from output pin 433a, and power line L1a is energized (for example, energized at a voltage of 24 V). This turns motor 51a ON. In this case, brake 52a is turned OFF, and head stage 50a is released from its fixed position, so that head stage 50a is moved by motor 51a.

[0060] Furthermore, switch 431b switches the electrical connection between input pin 432 and output pin 433b between ON and OFF. When switch 431b is OFF, the operation command input to input pin 432 is not output from output pin 433b, and power line L1b is in a non-energized state (for example, 0 V). This turns motor 51b OFF. In this case, brake 52b is ON, and head stage 50b is fixed by brake 52b.

[0061] [Operation of Inkjet Device 1] Before performing a "coating process" on the substrate W1, the inkjet device 1 performs a "nozzle adjustment process" to correct the positions of the nozzles 35 among the multiple heads 33. The nozzle adjustment process is performed at an appropriate timing, for example, when the coating conditions on the substrate W1 are changed (when the recipe is changed), when the ink state changes due to refilling the inkjet device 1 with ink, during calibration, or during initialization.

[0062] [Nozzle adjustment process] The nozzle adjustment process will be described below. Each of the following steps is realized by the control unit 41 performing various calculations and controls according to a predetermined program and outputting command signals to each part of the control unit 4, for example.

[0063] First, the inkjet device 1 applies a test pattern to a test substrate W1. Next, an inspection camera captures an image of the applied test pattern to obtain a test image. Then, based on the test image, various methods are used to evaluate the deviation in the landing positions of ink ejected from the nozzles 35 among the multiple heads 33. The method used for the evaluation is not particularly limited, and any known evaluation method using a known test pattern may be used.

[0064] Next, based on the evaluation, the control unit 41 acquires a correction amount for correcting the deviation of the ink landing position. As an example, as shown in Fig. 4, the control unit 41 acquires a correction amount for moving the nozzles 35 included in the A1 head 33 by +X1 [mm] in the X direction and -Y1 [mm] in the Y direction, and for rotating the nozzles 35 included in the C2 head 33 by +θ1 [°] in the θ direction.

[0065] Finally, the control unit 41 sequentially outputs command signals for the multiple motors 51 to the multiple servo amplifiers 42, and also outputs command signals to the multiple circuit units 43 to control the destination of the operation commands output from the servo amplifiers 42.

[0066] For example, in FIG. 5, consider a case where the drive mechanism 36a is the X-axis drive unit 362 of the A1 head 33, the drive mechanism 36b is the Y-axis drive unit 363 of the A1 head 33, and the drive mechanism 36c is the θ-axis drive unit 361 of the C2 head 33.

[0067] In this case, the control unit 41 first outputs a command signal to the first servo amplifier 42a to move the head stage 502 of the A1 head 33 by +X1 [mm], and also outputs a command signal to the first circuit unit 43a to turn on (closed state) the switch 431a and turn off (open state) the switch 431b. As a result, an operation command obtained by amplifying the command signal is output from the first servo amplifier 42a, input to the first circuit unit 43a, and then output from the output pin 433a via the switch 431a. The operation command is then output to the motor 51a and the brake 52a via the power line L1a (the state shown in FIG. 6).

[0068] This turns motor 51a ON and brake 52a (negative acting brake) OFF, so that while brake 52a releases the fixation of head stage 50a (i.e., head stage 502 of A1 head 33), motor 51a moves head stage 50a by +X1 [mm] in accordance with the operation command.

[0069] In this state, the switch 431b is OFF, so the operation command does not flow to the power line L1b, which turns the motor 51b OFF and the brake 52b ON, preventing the motor 51b from moving the head stage 50b (i.e., the head stage 503 of the A1 head 33), and maintaining the head stage 50b fixed by the brake 52b.

[0070] Next, the control unit 41 outputs a command signal to the first servo amplifier 42a to move the head stage 503 of the A1 head 33 by -Y1 [mm], and also outputs a command signal to the first circuit unit 43a to turn the switch 431a OFF (open state) and turn the switch 431b ON (closed state). As a result, an operation command obtained by amplifying the command signal is output from the first servo amplifier 42a and input to the first circuit unit 43a, and then output from the output pin 433b via the switch 431b. The operation command is then output to the motor 51b and the brake 52b via the power line L1b.

[0071] As a result, the motor 51b is turned on and the brake 52b is turned off, so that with the brake 52b releasing the fixation of the head stage 50b, the motor 51b moves the head stage 50b by -Y1 [mm] in accordance with the operation command.

[0072] In this state, the switch 431a is OFF, so the operation command does not flow to the power line L1a, which turns the motor 51a OFF and the brake 52a ON, preventing the motor 51a from moving the head stage 50a and maintaining the head stage 50a fixed by the brake 52a.

[0073] In parallel with outputting the command signal to the first servo amplifier 42a, the control unit 41 outputs a command signal to the second servo amplifier 42b to rotate the head stage 501 of the C2 head 33 by +θ1 [°], and also outputs a command signal to turn on (closed state) a switch 431, of the multiple switches 341 included in the second circuit unit 43b, that outputs an operation command to the drive mechanism 36c, and to turn off (open state) the other switches 431. As a result, an operation command obtained by amplifying the command signal is output from the second servo amplifier 42b, input to the second circuit unit 43b, and then output to the motor 51c and brake 52c via the specific switch 431 that has been turned on (the state shown in FIG. 6).

[0074] This turns motor 51c ON and brake 52c OFF, so that while brake 52c releases the head stage 50c (i.e., head stage 501 of C2 head 33), motor 51c rotates head stage 50c by +θ1 [°] in accordance with the operation command.

[0075] In this state, the other switches 431 in the second circuit section 43b are OFF, so the operation command does not flow to the power line L1 connected to the drive mechanisms 36 other than the drive mechanism 36c (for example, the drive mechanism 36d). As a result, the motor 51d is turned OFF and the brake 52d is turned ON, so the head stage 50d is not moved by the motor 51d, and the head stage 50d remains fixed by the brake 52d.

[0076] As described above, in accordance with the command signal from the control unit 41, the circuit unit 43 can enter a first state (a state illustrated in FIG. 6) in which it outputs an operation command from the servo amplifier 42 to a specific motor 51a (an example of the "first motor" in this disclosure) among the multiple motors 51, and does not output an operation command to any motor other than the motor 51a (e.g., motor 51b) electrically connected to the servo amplifier 42 via the circuit unit 43.

[0077] Then, the circuit unit 43 can be switched from this first state to a second state in response to a command signal from the control unit 41, in which the circuit unit 43 outputs an operation command for the servo amplifier 42 to a specific motor 51b (an example of a "second motor" in this disclosure) different from motor 51a among the multiple motors 51, and does not output an operation command to any motor (e.g., motor 51a) other than motor 51b that is electrically connected to the servo amplifier 42 via the circuit unit 43.

[0078] In this way, the circuit section 43 can transition from a first state in which it outputs an operation command to motor 51a of the plurality of motors 51 to a second state in which it outputs an operation command to motor 51b of the plurality of motors 51, so that the servo amplifiers 42 can be associated one-to-many with the plurality of motors 51. This makes it possible to reduce the number of servo amplifiers 42 that were conventionally required for each of the plurality of motors 51, and therefore the control unit 4, and therefore the inkjet device 1, can be made to have a simpler configuration.

[0079] Here, when the servo amplifier 42 and the motor 51 correspond one-to-one, the operation command of the servo amplifier 42 is constantly input to the motor 51, and therefore, when the head stage 50 is not moving, the position of the head stage 50 is fixed by the motor 51. In contrast, in the present disclosure, the motor 51 to which the operation command is not input from the servo amplifier 42 (for example, the motor 51b in the first state) is turned off, and therefore the head stage 50 moved by the motor 51 is in a free state if left as is, and there is a risk that the head stage 50 may move unexpectedly due to, for example, vibrations of the inkjet device 1.

[0080] Therefore, in this embodiment, a brake 52 is provided on each drive unit 36, and when the motor 51 is turned off, the brake 52 is turned on to fix the head stage 50. This makes it possible to suppress unexpected movement of the head stage 50 that occurs when the servo amplifier 42 and the multiple motors 51 are associated in a one-to-many relationship, and makes it possible to position the head stage 50 in an appropriate location.

[0081] In particular, in this embodiment, a negatively acting brake (e.g., a non-excitation brake) is used as the brake 52, and by sharing a power line with the motor 51, it is possible, with a simple configuration, to turn the brake 52 OFF when the motor 51 corresponding to the same head stage 50 is ON, and to turn the brake 52 ON when the motor 51 is OFF.

[0082] As described above, the nozzle adjustment process ends when the head stages 50 of all heads 33 to be corrected are moved sequentially in response to a command signal from the control unit 41. After the nozzle adjustment process ends, the motors 51 of all heads 33 are turned OFF, and the brakes 52 are maintained in an ON state.

[0083] [About coating process] After the nozzle adjustment process, the inkjet device 1 performs the "coating process." The coating process is a process for manufacturing a color filter by applying ink to the substrate W1. At the stage of the coating process, the position of the nozzle 35 has already been adjusted, so the nozzle 35 is not moved by the drive mechanism 36, and the substrate stage 22 is moved by the movement mechanism 23.

[0084] Specifically, with the substrate W1 placed on the substrate stage 22, the control unit 41 outputs a command signal to the servo amplifier 44, and also outputs a command signal to the head unit 32 to cause it to eject ink from the nozzles 35. As a result, an operation command obtained by amplifying the command signal is output from the servo amplifier 44 and input to the movement mechanism 23, causing the movement mechanism 23 to move the substrate stage 22 in the Y direction, as shown in FIG.

[0085] Then, in accordance with a command signal from the control unit 41, ink is ejected sequentially from the nozzles 35 of each head 33, causing the ink to land at a predetermined position on the substrate W1, which is moving in the Y direction together with the substrate stage 22. In this way, the ink is applied to the substrate W1.

[0086] In the inkjet device 1 of this embodiment, as shown in Figure 2, while the substrate W1 moves once in the direction of arrow AR1, ink is applied by the head unit 32, and a predetermined pattern is formed on the substrate W1, thereby completing the application process.

[0087] [Modification] Modifications of the embodiment will be described below. In the modifications, the same components as those in the embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

[0088] [Modification of brake] In the above embodiment, the brake 52 is a negative-acting brake, and shares the power line L1 with the motor 51 to alternately switch the motor 51 and the brake 52 ON and OFF. However, the brake 52 may be controlled independently of the motor 51.

[0089] 7 is a block diagram showing a schematic partial functional configuration of an inkjet device 1a according to a modified example. In this modified example, the control unit 4a differs from the control unit 4 (FIG. 5) mainly in that it further includes a brake control unit 45. The brake control unit 45 is a device that outputs operation commands to a plurality of brakes 52 in response to a command signal from the control unit 41, and is, for example, an amplifier device that amplifies the command signal.

[0090] The brake control unit 45 is electrically connected to the brake 52a via the power line L2a and to the brake 52b via the power line L2b. In this way, the brake control unit 45 is connected to the plurality of brakes 52 via the plurality of independent power lines L2 (a general term for power lines including the power lines L2a and L2b), and therefore can control the plurality of brakes 52 independently.

[0091] Although the brake control unit 45 is shown as one block in FIG. 7, the control unit 4a may have a plurality of brake control units 45, and each brake control unit 45 may correspond one-to-one to each brake 52.

[0092] Fig. 8 is an explanatory diagram of the nozzle adjustment process of this modified example. The right side of Fig. 8 shows a flowchart of the nozzle adjustment process, and the left side of Fig. 8 shows the states of the motors 51 and brakes 52 corresponding to each head stage 50 in each process. Below, the nozzle adjustment process of this modified example will be explained, focusing mainly on the differences from the above embodiment.

[0093] In the above embodiment, the motor 51 and the brake 52 are alternately switched on and off by sharing the power line L1, and therefore, because the change in power in the power line L1 is not instantaneous, the brake 52 may not be completely turned on the moment the motor 51 is turned off, and there may be a slight time lag between when the motor 51 is turned off and when the brake 52 is turned on. In this case, there is a time when both the motor 51 and the brake 52 are off, which may cause a slight positional deviation of the head stage 50.

[0094] Furthermore, when the brake 52 applies braking to the head stage 50 , the head stage 50 may be slightly displaced from the position determined by the motor 51 due to the clamping of the head stage 50 by the brake 52 .

[0095] Therefore, in this modified example, to suppress such positional deviation of the head stage 50, the control unit 4a independently controls the motor 51 and the brake 52. After roughly positioning the head stage 50 using the brake 52, the control unit 4a turns on the motor 51 while turning on the brake 52 to finely correct the position of the head stage 50. This makes it possible to position the head stage 50 at the commanded position with higher accuracy. The process of positioning the head stage 50a, as shown in FIG. 7, will now be described in detail.

[0096] First, the control unit 41 acquires the amount of correction to correct the misalignment of the nozzle 35, as in the above embodiment. Then, the control unit 41 outputs a command signal to the first servo amplifier 42a to move the head stage 50a by a predetermined amount of correction, and outputs a command signal to the first circuit unit 43a to turn the switch 431a ON (closed state) and the switch 431b OFF (open state). As a result, an operation command obtained by amplifying the command signal is output from the first servo amplifier 42a to the motor 51a via the switch 431a of the first circuit unit 43a.

[0097] At this time, the control unit 41 outputs a command signal to the brake control unit 45 to turn off the brake 52a and turn on the brakes 52 (including the brake 52b) other than the brake 52a. As a result, the motor 51a turns on and the brake 52a turns off, thereby positioning the head stage 50a at the commanded position (head positioning: step S10). Furthermore, the head stage 50b is maintained in a fixed state because the brake 52b is on.

[0098] Next, while keeping the motor 51a ON (i.e., maintaining the first state), the control unit 41 brakes the head 33 (specifically, the head stage 50a) moved by the motor 51a with the brake 52a (brake processing: step S11). Specifically, the control unit 41 outputs a command signal to the brake control unit 45 to turn on the brake 52a. As a result, an operation command obtained by amplifying the command signal is input from the brake control unit 45 to the brake 52a via the power line L2a, the brake 52a is activated, and the head stage 50a moved by the motor 51a is braked by the brake 52a.

[0099] In this state, the control unit 41 outputs a command signal to further move the motor 51a by a predetermined amount (position correction process: step S12). As a result, the head stage 50a moves to the commanded position by the motor 51a while being braked by the brake 52a. Since the brake 52a is already applied when the position adjustment of the head stage 50a by the motor 51a is completed, it is possible to prevent the position of the head stage 50a from being accidentally shifted when the motor 51a is switched off. As a result, the head stage 50a can be positioned to the commanded position with higher accuracy.

[0100] Furthermore, since the brake 52a is already applied when the position adjustment of the head stage 50a by the motor 51a is completed, the positional deviation of the head stage 50a that occurs when the brake 52a starts to be applied does not occur when the position adjustment of the head stage 50a is completed. Therefore, it is possible to prevent the influence of positional deviation caused by the clamp from affecting the position adjustment of the head stage 50a, and it is possible to position the head stage 50a at the command position with higher accuracy.

[0101] As described above, in the braking process and position correction process, while maintaining the first state, the control of moving the head stage 50a by the motor 51a in a state in which the head stage 50a moved by the motor 51a is braked by the brake 52a is referred to as “position adjustment control.” The control unit 41 executes the position adjustment control in the braking process and position correction process.

[0102] Thereafter, the control unit 41 determines whether the position of the head stage 50a is at a predetermined command position (determination process: step S13). In the determination process, for example, the control unit 41 acquires the position of the head stage 50a based on information about the current position of the motor 51a output from the motor 51a. In the position correction process (step S12), the brake 52a is turned ON while the motor 51a is kept ON, so that the control unit 41 can acquire the current position of the head stage 50a from the motor 51a when the head stage 50a stops. This allows the control unit 41 to more accurately grasp the current position of the head stage 50a.

[0103] If the position of the head stage 50a is not at the predetermined designated position (NO in step S13), the control unit 41 executes the position correction process (step S12) again to finely correct the position of the head stage 50a.

[0104] If the position of the head stage 50a is at the specified command position (YES in step S13), the control unit 41 ends the positioning of the head stage 50a and then switches the motor 51 to be controlled from motor 51a to motor 51b in order to position the head stage 50b (motor switching process: step S14).

[0105] In the motor switching process, the control unit 41 outputs a command signal to the first servo amplifier 42a to move the head stage 50b by a predetermined correction amount, and outputs a command signal to the first circuit unit 43a to turn off the switch 431a and turn on the switch 431b. As a result, an operation command obtained by amplifying the command signal is output from the first servo amplifier 42a to the motor 51b via the switch 431b of the first circuit unit 43a (second state). In other words, the motor switching process includes switching control in which the control unit 41 switches the circuit unit 43 from the first state to the second state.

[0106] Then, head stage 50b is also positioned by performing the processes of steps S10 to S13 in the same manner as head stage 50a. As described above, when control unit 41 has positioned the head stages 50 of all heads 33 that are the subject of correction, the nozzle adjustment process according to this modified example is completed.

[0107] In the above, a negatively acting brake has been described as an example of the brake 52 as shown in Figure 7, but since the brake 52 is controlled by a power line L2 separate from the motor 51, a positively acting brake (e.g., an electromagnetic brake) that fixes the head 33 when current is applied and releases the head 33 from the fixation when current is not applied may be used instead of the negatively acting brake.

[0108] Furthermore, among the multiple drive mechanisms 36 included in the head unit 32, only the drive mechanisms 36 that require particularly high positioning accuracy may be configured to have the motor 51 and brake 52 controlled independently as shown in FIG. 7, while the other drive mechanisms 36 may be configured to have the motor 51 and brake 52 controlled alternately by sharing the power line L1 as shown in FIG. 5.

[0109] [Modification of head unit] In the above embodiment, the width of the head unit 32 in the X direction is equal to or wider than the width of the substrate W1 in the same direction, so that the coating process can be completed on the entire surface of the substrate W1 while the substrate W1 is moved once in the direction of arrow AR1. However, in the inkjet device of the present disclosure, the width of the head unit in the X direction may be narrower than the width of the substrate W1 in the same direction.

[0110] 9 is a plan view schematically showing an inkjet device 1b according to a modified example. The inkjet device 1b differs from the inkjet device 1 according to the above embodiment mainly in that the width of the head unit 32a in the X direction is narrower than the width of the substrate W1 in the same direction. Also, while the inkjet device 1b shows a "cantilevered" type gantry 31 as an example, it may be a "double-supported" type using two gantries 31, 31, as in the above embodiment.

[0111] Head unit 32a is a unit in which heads 33 are arranged in three rows, in columns A, B, and C, in that order from the negative side in the Y direction (nine heads 33 in three columns and three rows). That is, head unit 32a has approximately half the width of head unit 32 (FIG. 2) in the X direction. Beam section 31b includes a movement mechanism (not shown) that moves head unit 32a in the X direction.

[0112] The head unit 32a also performs the nozzle adjustment process in the same manner as in the above embodiment. Then, after the nozzle adjustment process, the coating process is performed. In the coating process of this modified example, with the head unit 32a positioned on the positive side of the X direction (the state shown in FIG. 9), a predetermined pattern is coated on half of the area on the positive side of the X direction of the substrate W1 while the substrate W1 moves once in the direction of arrow AR1.

[0113] Thereafter, the head unit 32a is moved in the direction of the arrow AR2, and while the substrate W1 is moved once in the direction of the arrow AR3 with the head unit 32a positioned on the negative side of the X direction, a predetermined pattern is applied to half of the area of ​​the substrate W1 on the negative side in the X direction. As a result, the entire surface of the substrate W1 is coated with the predetermined pattern, and the coating process is completed.

[0114] In this way, in this modified example, ink is applied by the head unit 32a while the substrate W1 makes one round trip over the head unit 32a, so the movement time of the substrate W1 is longer than in the above embodiment, and the manufacturing time per substrate W1 is longer. On the other hand, the number of heads 33 is smaller than in the above embodiment, so it is easier to keep the manufacturing costs and management costs of the head unit 32a lower than in the above embodiment.

[0115] In the inkjet device 1b in which the head unit 32a itself is moved in the X direction during the coating process as in this modified example, the nozzles 35 are aligned using multiple motors 51, as in the above embodiment. Therefore, by associating the servo amplifiers 42 with the motors 51 in a one-to-many relationship, the number of servo amplifiers 42 can be reduced, and the control unit 4 can be configured more simply.

[0116] <Additional Notes> The embodiments and modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of equivalents to the configurations described in the claims. [Explanation of symbols]

[0117] 1,1a,1b Inkjet device 2 Stage Unit 22 Substrate stage 3 Coating unit 32,32a head unit 33 head 35 nozzles 4,4a Control unit 41 Control Unit 42 Servo amplifier 43 Circuit section 50 Headstage 51 Motor 52 Brake L1 power line

Claims

1. An inkjet device comprising: a head unit having a plurality of heads that eject ink onto a substrate placed on a stage; and applying ink to the substrate by causing ink to land at predetermined positions on the substrate that moves relatively to the head unit, a plurality of motors that change the relative positions of nozzles among the plurality of heads in the head unit by moving the plurality of heads, respectively; a servo amplifier that outputs an operation command to the motor; a circuit section that switches an electrical connection state between the plurality of motors and the servo amplifier; Equipped with the circuit unit is switchable from a first state in which an operation command of the servo amplifier is output to a first motor of the plurality of motors to a second state in which an operation command of the servo amplifier is output to a second motor of the plurality of motors that is different from the first motor, Inkjet device.

2. further comprising a plurality of brakes for fixing the positions of the plurality of heads, the plurality of brakes fix the positions of the heads among the plurality of heads that are moved by the motor and are not connected to the servo amplifier by the circuit unit; The inkjet device according to claim 1 .

3. the brake includes a negative-acting brake that releases the fixation of the head when energized and fixes the head when de-energized, The negative acting brake is energized from a power supply line that inputs an operation command from the servo amplifier to the motor. The inkjet device according to claim 2 .

4. a control unit that controls the circuit unit, the plurality of heads, and the plurality of brakes, The control unit a position adjustment control for moving the head by the first motor in the first state while the head moved by the first motor is braked by the brake; a switching control for switching the circuit unit from the first state to the second state after the position adjustment control; To execute The inkjet device according to claim 2 .

5. a plurality of servo amplifiers including a first servo amplifier that sequentially outputs operation commands to a plurality of the motors that belong to a first group, and a second servo amplifier that sequentially outputs operation commands to a plurality of the motors that belong to a second group that is different from the first group; the first group and the second group are groups in which the plurality of motors are grouped according to the rows or columns in which the heads moved by the motors are arranged, or according to the movement axes of the heads moved by the motors; The inkjet device according to any one of claims 1 to 4.

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