JP2013244449A - Drawing apparatus and drawing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that drawing quality cannot be improved in a conventional drawing apparatus.SOLUTION: A displacement section displaces a discharge head which discharges a liquid-state substance. A scale includes a plurality of divisions which are disposed side by side along a direction of the displacement. A first detection section detects a division with the displacement of the discharge head. A second detection section detects head position information indicating a position of the discharge head. A control section controls the timing for the discharge head to discharge the liquid-state substance based on the division detects by the first detection section and the head position information detected by the second detection section.

Description

  The present invention relates to a drawing apparatus, a drawing method, and the like.

In recent years, apparatuses such as inkjet printers have been used for business and industrial purposes. For example, inkjet printers are used for printing signboards and huge posters, or for producing color filters. Such business and industrial printers have a longer width (scan width) in which the head for ejecting ink moves than a consumer printer. In addition, the printer is provided with a scale for controlling the position of the head. The printer controls printing by reading the scale scale. In business and industrial printers, the scan width is long, so the scale is also long.
By the way, some of these scales expand and contract due to temperature changes and the like. Since the scale for business and industrial printers is longer than that for consumer printers, the effects of scale expansion and contraction are prominent.

  On the other hand, Patent Document 1 discloses a pattern formation in which a control pulse is generated using a signal for each predetermined length output from a linear scale means, and a pattern is formed on a display panel based on the control pulse. In the apparatus, pulse signal generating means for generating a pulse signal having a period smaller than the control pulse by dividing the signal output from the linear scale means, and the control by counting a predetermined number of the pulse signals. Control pulse generating means for generating a pulse for use, and when the predetermined length of the signal output from the linear scale means changes in accordance with a change in the environmental temperature of the pattern forming apparatus, it counts according to the rate of the change And a control pulse generating means for generating the control pulse by varying the predetermined number. Over emissions forming apparatus is described. Patent Document 1 describes that the linear scale is actually measured using a laser length measurement or the like after being mounted on the apparatus.

JP 2008-196953 A

  However, the technique described in Patent Document 1 has a problem that after the linear scale is mounted on the apparatus, the length must be actually measured using laser length measurement or the like, and this work is burdened. Further, when the length is not measured correctly, or when the length of the linear scale or the degree of expansion / contraction changes after the length measurement, there is a problem that the accuracy of the ink ejection position cannot be increased. As described above, the technique described in Patent Document 1 has a problem that the drawing quality may not be improved.

  The present invention has been made to solve the above problems, and one aspect of the present invention includes a displacement portion that displaces a discharge head that discharges a liquid material, and a plurality of scales arranged along the direction of the displacement. A scale provided; a first detection unit that detects the scale in accordance with displacement of the ejection head; a second detection unit that detects head position information indicating a position of the ejection head; and the first detection unit. A drawing apparatus comprising: a scale detected by a detection unit; and a control unit that controls a timing at which the discharge head discharges the liquid material based on head position information detected by the second detection unit.

  According to another aspect of the present invention, in the above drawing apparatus, the control unit is configured to perform the timing based on the number of scales detected by the first detection unit and head position information detected by the second detection unit. The amount of correction is calculated.

  In one embodiment of the present invention, in the above drawing apparatus, the second detection unit detects that the ejection head has reached a predetermined position, and the control unit is configured so that the ejection head is predetermined. The timing correction amount is calculated based on the number of scales detected by the first detection unit before reaching the position.

  In one embodiment of the present invention, in the above drawing apparatus, the second detection unit detects that the ejection head has reached a predetermined first position and a second position, The control unit calculates the correction amount of the timing based on the number of scales detected by the first detection unit until the ejection head reaches the second position from the predetermined first position. To do.

  Another embodiment of the present invention is a drawing method in a drawing apparatus, wherein the drawing apparatus displaces a discharge head that discharges a liquid material, and a direction of the displacement in accordance with the displacement of the discharge head. A first detection process for detecting a plurality of scales arranged along the line, a second detection process in which the drawing apparatus detects head position information indicating the position of the ejection head, and the drawing apparatus has the first detection process. And a head control process for controlling the timing at which the discharge head discharges the liquid material based on the head position information detected in the second detection process. .

FIG. 2 is a perspective view illustrating a schematic configuration of a droplet discharge device according to the present embodiment. The front view when the carriage in this embodiment is seen in the A viewing direction in FIG. FIG. 6 is a bottom view of the ejection head in the present embodiment. Sectional drawing in the BB line in FIG. FIG. 2 is a perspective view illustrating a schematic configuration of a carriage position detection device according to the present embodiment. The perspective view which shows the structure of the outline of the encoder in this embodiment. The front view when the encoder in this embodiment is seen in E view direction in FIG. Sectional drawing in the HH line | wire in FIG. FIG. 2 is a block diagram showing a schematic configuration of a droplet discharge device in the present embodiment. FIG. 2 is a block diagram illustrating a schematic configuration of a head control unit according to the present embodiment. The timing chart which shows the example in the ideal state of the encoder signal in this embodiment. The conceptual diagram which shows the example of the expansion-contraction by the temperature of the linear scale in this embodiment. The timing chart which shows an example of the encoder signal in this embodiment. The timing chart which shows the encoder signal and discharge timing signal in this embodiment. The flowchart showing the drawing process in this embodiment. The perspective view which shows the structure of the outline of the carriage position detection apparatus in the modification 1 of this embodiment. The perspective view which shows the structure of the outline of the carriage position detection apparatus in the modification 2 of this embodiment.

  Embodiments will be described with reference to the drawings, taking as an example a droplet discharge device that is one of the drawing devices. In addition, in each drawing, in order to make each structure the size which can be recognized, the structure and the scale of a member may differ.

As shown in FIG. 1, which is a perspective view showing a schematic configuration, a droplet discharge device 1 in the present embodiment includes a work transfer device 3, a carriage 7, and a carriage transfer device 11.
The carriage 7 is provided with a head unit 13.
In the droplet discharge device 1 shown in FIG. 1, the work W is discharged by discharging a liquid material as droplets from the head unit 13 while changing the relative position of the head unit 13 and the workpiece W such as a substrate in plan view. In addition, a desired pattern can be drawn (recorded) with a liquid material. In the figure, the Y direction indicates the moving direction of the workpiece W, and the X direction indicates a direction orthogonal to the Y direction in plan view. A direction orthogonal to the XY plane defined by the X direction and the Y direction is defined as the Z direction.

Such a droplet discharge device 1 can be applied to drawing (recording) on various workpieces W.
The droplet discharge device 1 can also be applied to, for example, the manufacture of color filters used in liquid crystal display panels and the like, and the manufacture of organic EL devices.
In the case of a color filter having three color filter elements of red, green, and blue, the droplet discharge device 1 can be suitably used, for example, in a process of forming red, green, and blue colored layers on a substrate. In this case, each liquid corresponding to each colored layer is ejected as droplets from the head unit 13 onto the workpiece W, which is a substrate, so that the pattern of the red, green, and blue filter elements is drawn on the workpiece W. .
Further, in the manufacture of an organic EL device, for example, it can be suitably used in a step of forming a functional layer (organic layer) corresponding to each color for each of red, green and blue pixels. In this case, each liquid material corresponding to the functional layer of each color is ejected from the head unit 13 as droplets onto the work W, whereby the patterns of the red, green, and blue functional layers are drawn on the work W.
The workpiece W as a recording medium is not limited to the above-described substrate, and various recording media such as a resin film, paper, cloth, and metal foil can be employed.

Here, the details of each component of the droplet discharge device 1 will be described.
As shown in FIG. 1, the work transfer device 3 includes a surface plate 21, a guide rail 23 a, a guide rail 23 b, a work table 25, and a table position detection device 27.
The surface plate 21 is made of a material having a small coefficient of thermal expansion, such as stone, and is placed so as to extend along the Y direction. Each of the guide rail 23a and the guide rail 23b extends along the Y direction. The guide rail 23a and the guide rail 23b are arranged in a state where there is a gap in the X direction.

  The work table 25 is provided in a state facing the upper surface 21a of the surface plate 21 with the guide rail 23a and the guide rail 23b interposed therebetween. The work table 25 is placed on the guide rail 23 a and the guide rail 23 b with the upper body floating from the surface plate 21. The work table 25 has a placement surface 25a that is a surface on which the workpiece W is placed. The placement surface 25a is directed to the side (upper side) opposite to the surface plate 21 side. The work table 25 is guided along the Y direction by the guide rail 23a and the guide rail 23b, and extends on the surface plate 21 in the Y direction. The table position detector 27 detects the position of the work table 25 in the Y direction.

The work table 25 is configured to reciprocate in the Y direction by a moving mechanism and a power source (not shown). As the moving mechanism, for example, a mechanism combining a ball screw and a ball nut, a linear guide mechanism, or the like may be employed. In the present embodiment, a work transfer motor described later is employed as a power source for moving the work table 25 along the Y direction. As the work transfer motor, various motors such as a stepping motor, a servo motor, and a linear motor can be adopted.
The power from the work transport motor is transmitted to the work table 25 through the moving mechanism. Thereby, the workpiece | work W mounted on the mounting surface 25a of the work table 25 can be reciprocated along the Y direction. At this time, the position of the work table 25 in the Y direction is controlled based on the detection result by the table position detection device 27.

The head unit 13 includes a head plate 31 and an ejection head 33 as shown in FIG. 2 which is a front view when the carriage 7 is viewed in the direction A in FIG.
As shown in FIG. 3 which is a bottom view, the discharge head 33 has a nozzle surface 35. A plurality of nozzles 37 are formed on the nozzle surface 35. In FIG. 3, the nozzles 37 are exaggerated and the number of the nozzles 37 is reduced in order to easily show the nozzles 37.
In the ejection head 33, the plurality of nozzles 37 constitute a nozzle row 39 arranged along the Y direction. In the nozzle row 39, the plurality of nozzles 37 are formed at a predetermined nozzle interval P along the Y direction.

The ejection head 33 includes a nozzle plate 46, a cavity plate 47, a diaphragm 48, and a plurality of piezoelectric elements 49, as shown in FIG. 4 which is a cross-sectional view taken along the line BB in FIG. doing.
The nozzle plate 46 has a nozzle surface 35. The plurality of nozzles 37 are provided on the nozzle plate 46.
The cavity plate 47 is provided on the surface opposite to the nozzle surface 35 of the nozzle plate 46. The functional liquid 53 is supplied to the cavity plate 47 from a tank (not shown).

The diaphragm 48 is provided on the surface of the cavity plate 47 opposite to the nozzle plate 46 side. The vibration plate 48 vibrates in the Z direction (longitudinal vibration), thereby enlarging or reducing the volume in the cavity 51.
The plurality of piezoelectric elements 49 are respectively provided on the surface of the diaphragm 48 opposite to the cavity plate 47 side. Each piezoelectric element 49 is provided corresponding to each cavity 51 and faces each cavity with the diaphragm 48 interposed therebetween. Each piezoelectric element 49 expands based on the drive signal. Thereby, the diaphragm 48 reduces the volume in the cavity 51. At this time, pressure is applied to the functional liquid 53 in the cavity 51. As a result, the functional liquid 53 is discharged as droplets 55 from the nozzle 37. The method of discharging the droplet 55 by the discharge head 33 is one of ink jet methods. The ink jet method is one of painting methods.

As shown in FIG. 2, the ejection head 33 having the above configuration is supported by the head plate 31 with the nozzle surface 35 protruding from the head plate 31.
As shown in FIG. 2, the carriage 7 supports the head unit 13. Here, the head unit 13 is supported by the carriage 7 with the nozzle surface 35 facing downward in the Z direction.
As described above, the functional liquid 53 can be applied to the workpiece W from the ejection head 33.
In the present embodiment, the longitudinal vibration type piezoelectric element 49 is adopted, but the pressurizing means for applying pressure to the functional liquid 53 is not limited to this, and for example, the lower electrode and the piezoelectric layer A flexural deformation type piezoelectric element in which an electrode and an upper electrode are laminated may be employed. Further, as the pressurizing means, a so-called electrostatic actuator that generates static electricity between the diaphragm and the electrode, deforms the diaphragm by electrostatic force, and discharges droplets from the nozzles can be employed. Furthermore, the structure which generate | occur | produces a bubble in a nozzle using a heat generating body, and gives a pressure to a functional liquid with the bubble may be employ | adopted.

As shown in FIG. 1, the carriage conveyance device 11 includes a gantry 61, a guide rail 63, and a carriage position detection device 65.
The gantry 61 extends in the X direction and straddles the work transfer device 3 in the X direction. The gantry 61 faces the work transfer device 3 on the side opposite to the surface plate 21 side of the work table 25. The gantry 61 is supported by a pair of support columns 67. The pair of struts 67 are provided at positions facing each other in the X direction with the surface plate 21 interposed therebetween.
In the following, when identifying each of the pair of columns 67, the notations of columns 67a and columns 67b are used. Each of the support columns 67a and the support columns 67b protrudes above the work table 25 in the Z direction. Thereby, a gap is maintained between the gantry 61 and the work table 25.

The guide rail 63 is provided on the surface plate 21 side of the gantry 61. The guide rail 63 extends along the X direction, and is provided across the width of the gantry 61 in the X direction.
The carriage 7 described above is supported by the guide rail 63. In a state where the carriage 7 is supported by the guide rail 63, the nozzle surface 35 of the discharge head 33 faces the work table 25 side in the Z direction. The carriage 7 is guided along the X direction by the guide rail 63, and is supported by the guide rail 63 so as to be able to reciprocate in the X direction.
In a plan view, in a state where the carriage 7 overlaps the work table 25, the nozzle surface 35 and the mounting surface 25a of the work table 25 face each other with a gap therebetween.
The carriage position detection device 65 is provided between the gantry 61 and the carriage 7 and extends in the X direction. The carriage position detection device 65 detects the position of the carriage 7 in the X direction.

The carriage 7 is configured to reciprocate in the X direction by a moving mechanism and a power source (not shown). As the moving mechanism, for example, a mechanism combining a ball screw and a ball nut, a linear guide mechanism, or the like may be employed. Further, the carriage transport device 11 has a carriage transport motor, which will be described later, as a power source for moving the carriage 7 along the X direction. As the carriage conveyance motor, various motors such as a stepping motor, a servo motor, and a linear motor can be employed.
The power from the carriage transport motor is transmitted to the carriage 7 through the moving mechanism.
Thereby, the carriage 7 can be reciprocated along the guide rail 63, that is, along the X direction. At this time, the position of the carriage 7 in the X direction is controlled based on the detection result by the carriage position detection device 65.
In the droplet discharge device 1 having the above-described configuration, the droplet 55 is discharged from the discharge head 33 while the discharge head 33 and the workpiece W are relatively moved while the discharge head 33 is opposed to the workpiece W. As a result, the pattern is drawn (recorded) on the workpiece W. In the present embodiment, the relative movement between the ejection head 33 and the workpiece W is achieved by the workpiece conveyance device 3 and the carriage conveyance device 11.

Here, the carriage position detection device 65 has a linear scale 71 and an encoder 73 as shown in FIG.
The linear scale 71 is provided on the gantry 61 and extends along the X direction. A plurality of scales 75 are engraved on the linear scale 71 along the X direction. These scales 75 serve as indicators of the amount of displacement of the carriage 7 in the X direction. In the present embodiment, the gantry 61 is made of a steel material.
In the encoder 73, as shown in FIG. 6, the light emitting element 73a and the optical sensor 73b face each other. The optical sensor 73b can detect light and darkness of light from the light emitting element 73a.

The linear scale 71 is located between the light emitting element 73a of the encoder 73 and the optical sensor 73b. In this embodiment, the linear scale 71 has a configuration in which a scale 75 having a high light absorption property is formed on a resin-made main body 71a having a light transmission property by a printing method. For this reason, when the linear scale 71 and the encoder 73 are displaced relative to each other, the intensity of light from the light emitting element 73 a to the optical sensor 73 b is changed by the plurality of scales 75.
The encoder 73 can detect the scale 75 of the linear scale 71 by detecting the intensity of light from the light emitting element 73a by the optical sensor 73b. Each time the encoder 73 detects the scale 75 of the linear scale 71, the encoder 73 outputs a detection pulse which is a pulse signal.

As shown in FIG. 5, the linear scale 71 is supported on the pedestal 61 by a screw 82 at one end 78 a side through a spacer 81. The other end 78 b side of the linear scale 71 is supported on the pedestal 61 by a screw 85 via a tension spring 83 and a spacer 84. Tension is applied to the linear scale 71 along the X direction from the other end 83b side by a tension spring 83.
A gap is maintained in the Y direction between the linear scale 71 and the gantry 61 by the spacer 81 and the spacer 84. An encoder 73 is inserted in this gap.
The encoder 73 is fixed to the carriage 7. For this reason, when the carriage 7 is displaced, the linear scale 71 and the encoder 73 are displaced relative to each other.
The carriage position detection device 65 having the above-described configuration can detect the displacement amount of the carriage 7 by detecting the scale 75 of the linear scale 71 with the encoder 73. In the droplet discharge device 1, the displacement amount and position of the carriage 7 are controlled based on the detection result by the carriage position detection device 65.

In the present embodiment, as shown in FIG. 5, the reference sensor S <b> 1 is provided on the other end 78 b side of the linear scale 71. The reference sensor S1 is provided at a position where it does not come into contact with the carriage 7 or the encoder 73. The reference sensor S1 is composed of, for example, a light emitting element and an optical sensor. The reference sensor S1 detects that the encoder 73 has reached a predetermined detection position. That is, the reference sensor S1 detects position information indicating the position of the carriage 7 (head unit 13, ejection head 33). Specifically, when the encoder 73 reaches the detection position, the light emitted from the light emitting element is reflected by the encoder 73. The reference sensor S1 detects that the encoder 73 has reached the detection position by detecting the reflected light with an optical sensor. The detection position is a position where the encoder 73 has an end on the other end 78b side when the encoder 73 moves to the other end 78a side.
The reference sensor S1 generates a carriage detection signal CP indicating that the encoder 73 has reached the detection position, and outputs the generated carriage detection signal CP to the CPU 113.

FIG. 7 is a front view when the encoder is viewed in the E viewing direction in FIG. 8 is a cross-sectional view taken along line HH in FIG. However, in FIG. 8, the reference sensor S1 is schematically shown as a side view when viewed in the E viewing direction in FIG.
As shown in FIG. 8, in this embodiment, the detection direction (optical path direction; Y direction) of the light emitting element 73a and the optical sensor 73b and the detection direction (optical path direction; Z direction) of the reference sensor S1 are orthogonal to each other. ing. Further, the linear scale 71 and the optical path L1 (one-dot chain line) when the light from the reference sensor S1 travels straight are shifted in the Y direction so as not to overlap. As a result, the reference sensor S1 is not affected by the detection of the light emitting element 73a and the optical sensor 73b. For example, the encoder 73 detects the light from the reference sensor S1 without being reflected or blocked by the linear scale 71. It can be detected that the position has been reached.

The reference sensor S1 is fixed to the gantry 61 via a guide rail 63. The guide rail 63 is made of, for example, a steel material, and is less stretchable due to a temperature change, for example, than the linear scale 71, and hardly stretches. That is, the position of the reference sensor S1 and the detection position detected by the reference sensor S1 are not changed by a temperature change or the like. Further, as shown in FIG. 5, G represents the distance from a predetermined reference starting point to the detection position. The reference starting point is a position where the end of the encoder 73 on the other end 78b side is located when the encoder 73 is moved most toward the one end 78a side. That is, the distance G is the scan width. Further, immediately after the encoder 73 starts moving from the reference starting point, the first pulse of the detection pulse KP described later is output.
However, the present invention is not limited to this, and the detection position and the reference point may be other positions. In that case, the distance G may be different from the scan width.

The reference sensor S1 may be a photo interrupter, a laser sensor, or a mechanical switch. For example, the optical sensor is provided at a position facing the light emitting element, and is provided at a position where the light from the light emitting element to the optical sensor is blocked by the encoder 73 when the encoder 73 reaches the detection position. Also good. Further, for example, when the encoder 73 reaches the detection position, electrodes that contact each other may be provided. In this case, by outputting a signal when the electrodes are in contact, the encoder 73 has reached the detection position. To detect. The reference sensor S1 may directly detect the distance (displacement amount) that the carriage 7 has moved.
Further, the reference sensor S1 may be provided in another place. In addition, either the light emitting element or the optical sensor may be provided in another place. For example, the light emitting element may be provided in the encoder 73 so as to face the optical sensor of the reference sensor S1 when the encoder 73 reaches the detection position.

As shown in FIG. 9, the droplet discharge device 1 includes a control unit 111 that controls the operation of each of the above-described configurations. The control unit 111 includes a CPU (Central Processing Unit) 113, a drive control unit 115, and a memory unit 117. The drive control unit 115 and the memory unit 117 are connected to the CPU 113 via the bus 119.
The droplet discharge device 1 includes a carriage transport motor 121, a work transport motor 123, an input device 129, and a display device 131.
The carriage transport motor 121 and the work transport motor 123, and the encoder 73 and the table position detection device 27 are connected to the control unit 111 via the input / output interface 133 and the bus 119, respectively. The input device 129 and the display device 131 are also connected to the control unit 111 via the input / output interface 133 and the bus 119, respectively.

The carriage transport motor 121 generates power for driving the carriage 7.
The work conveyance motor 123 generates power for driving the work table 25.
The input device 129 is a device for inputting various processing conditions. The display device 131 is a device that displays processing conditions and work status. An operator who operates the droplet processing device 1 can input various information via the input device 129 while confirming information displayed on the display device 131.
The ejection head 33 is also connected to the control unit 111 via the input / output interface 133 and the bus 119.

The CPU 113 performs various arithmetic processes as a processor. The drive control unit 115 controls driving of each component. The memory unit 117 includes a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. In the memory unit 117, an area for storing the program software 135 in which the operation control procedure in the droplet discharge device 1 is described, a data development unit 137 that is an area for temporarily developing various data, and the like are set. Yes. Examples of data developed in the data development unit 137 include drawing data indicating a pattern to be drawn, program data such as drawing processing, and the like.
The drive control unit 115 includes a motor control unit 141, a head control unit 145, and a display control unit 151.

The motor control unit 141 individually controls the drive of the carriage transport motor 121 and the drive of the work transport motor 123 based on a command from the CPU 113.
The head controller 145 controls driving of the ejection head 33 based on a command from the CPU 113.
The display control unit 151 controls driving of the display device 131 based on a command from the CPU 113.

In the droplet discharge device 1 having the above configuration, when the control unit 111 receives drawing data from the input device 129 via the input / output interface 133 and the bus 119, the drawing process is started by the CPU 113.
Here, the drawing data indicates a pattern to be drawn on the workpiece W with the functional liquid 53 (liquid material), and dots to be formed with the droplets 55 are expressed in a bitmap shape. The pattern drawn on the workpiece W is expressed as a set of a plurality of dots formed by the droplets 55. In drawing the pattern on the workpiece W, the droplets 55 are ejected from the ejection head 33 at a predetermined cycle while the ejection head 33 and the workpiece W are relatively moved with the ejection head 33 facing the workpiece W. Is done by. In the present embodiment, a pattern is drawn on the workpiece W by ejecting the droplets 55 from the ejection head 33 while driving the carriage 7 along the X direction with the conveyance of the workpiece W stopped. . In drawing on the workpiece W, the workpiece W may be broken. The line feed of the workpiece W is performed by transporting the workpiece W in the Y direction in a state where the ejection of the droplet 55 from the ejection head 33 is stopped.

In the present embodiment, the head controller 145 includes an ejection timing signal generator 171, a head drive controller, and a head drive circuit 175 as shown in FIG.
The discharge timing signal generation unit 171 outputs a discharge timing signal TS. In the discharge timing signal TS, a pulse-like discharge timing pulse to be described later appears at a timing when the discharge of the droplet 55 is permitted. The ejection of the droplet 55 is permitted based on the rise of the ejection timing pulse. That is, in the present embodiment, while the CPU 113 instructs the ejection head 33 to perform drawing, ejection of the droplet 55 by the ejection head 33 is permitted every time the ejection timing pulse rises.

Encoder signal EP and correction signal HS are input to discharge timing signal generation unit 171. The encoder signal EP is output from the encoder 73. In the encoder signal EP, every time the scale 75 of the linear scale 71 is detected, a detection pulse that is a pulse-like signal appears.
The correction signal HS is a signal indicating a time interval correction amount ΔT with respect to the pulse interval, and is output from the CPU 113. Here, the pulse interval is an interval between adjacent detection pulses in the encoder signal EP. The encoder signal EP is also input to the CPU 113. The CPU 113 generates a correction signal HS based on the input encoder signal EP and carriage detection signal CP.

The ejection timing signal generation unit 171 corrects the pulse interval in the encoder signal EP based on the correction signal HS. The discharge timing signal generation unit 171 outputs a discharge timing pulse at a correction time interval Th obtained by correcting the pulse interval.
The ejection timing signal TS is input to the head drive control unit. The head drive control unit 173 receives the ejection timing signal TS and the drawing command signal IS. The drawing command signal IS is a signal output from the CPU 113 and indicates information that instructs the ejection head 33 whether or not to execute drawing. The head drive control unit outputs a discharge timing signal TS to the head drive circuit 175 when the drawing command signal IS instructs the discharge head 33 to execute drawing (hereinafter referred to as an ON state). The head driving circuit 175 drives the ejection head 33 based on the inputted ejection timing signal TS, and ejects the droplet 55 from the nozzle 37. At this time, the ejection head 33 selectively ejects droplets 55 at every rising edge (or falling edge) of the ejection timing pulse from a plurality of nozzles based on the bitmap drawing data.
As described above, drawing on the workpiece W can be performed.

By the way, originally, when the carriage 7 is driven, a detection pulse KP corresponding to detection of the scale 75 appears in the encoder signal EP for each predetermined displacement amount. Therefore, originally, if the droplet 55 is ejected from the ejection head 33 toward the workpiece W for each detection pulse KP, the workpiece W has a predetermined interval F (distance) as shown in FIG. A dot Dt can be formed.
The interval F originally does not change depending on the displacement speed (conveyance speed) of the carriage 7. In this case, originally, when the carriage 7 is driven at a constant speed, the encoder signal EP output from the encoder 73 includes a detection pulse KP corresponding to the detection of the scale 75 as shown in FIG. Appears at S (time).
Note that the interval F is an interval related to distance. The interval S is a time interval. In the following, in order to distinguish between an interval related to distance and an interval related to time, an interval related to distance is called a distance interval, and an interval related to time is called a time interval.

  Thus, when the carriage 7 is driven at a constant speed, the detection pulse KP corresponding to the detection of the scale 75 appears at a constant time interval S and a constant distance interval F. However, when the linear scale 71 expands or contracts due to, for example, the environmental temperature, the appearance of the detection pulse KP deviates from the time interval S or the distance interval F. This is because the interval between the scales 75 is expanded and contracted by the expansion and contraction of the linear scale 71.

For example, at a certain temperature T ₀ (for example, 20 ° C.), the number of detection pulses (number of scales 75) from the reference start point to the detection position (when the movement distance of the carriage 7 is G) is 10,000. A case will be described. The number of detection pulses that appear from the reference starting point to the detection position is also referred to as a pulse count number.
At a temperature T ₁ (T ₁ > T ₀ ) higher than the temperature T ₀ , the linear scale 71 is longer and longer than that at the temperature T ₀ . If temperature _{T 1,} as shown in FIG. 12 (a), the pulse count number, for example, is 9,900 pieces. That is, the pulse count number is lower at the temperature T ₁ than at the temperature T ₀ .
On the other hand, at a temperature T ₂ (T ₂ <T ₀ ) that is higher than the temperature T ₀ , the linear scale 71 contracts and becomes shorter than that at the temperature T ₀ . If temperature _{T 2,} as shown in FIG. 12 (b), the pulse count number, for example, is 10,100. In other words, the pulse count number is larger is better when the temperature T ₂ than at the temperature T _0.

  When the linear scale 71 extends, the distance interval L between the adjacent dots Dt becomes larger than the distance interval F as shown in FIG. Conversely, when the linear scale 71 shrinks, the distance interval L between adjacent dots Dt is smaller than the distance interval F.

In the present embodiment, it is assumed that the shift amount ΔL of the distance interval L with respect to the distance interval F due to expansion and contraction of the linear scale 71 is uniform over the distance G shown in FIG.
In the example shown in FIG. 13A, the distance interval L (1) between the first dot Dt (1) and the second dot Dt (2) is larger than the distance interval F by a deviation amount ΔL. Similarly, the distance interval L (k) between the kth dot Dt (k) and the (k + 1) th dot Dt (k + 1) is also larger than the distance interval F by a deviation amount of ΔL.
In this case, even if the carriage 7 is driven at a constant speed, in the encoder signal EP output from the encoder 73, as shown in FIG. 13B, the time interval T between adjacent detection pulses KP is It becomes larger than the time interval S. In the example shown in FIG. 13B, the time interval T (1) between the first detection pulse KP (1) and the second detection pulse KP (2) is larger than the time interval S by ΔT. Similarly, the time interval T (k) between the kth detection pulse KP (k) and the (k + 1) th detection pulse KP (k + 1) is also larger than the time interval S by ΔT.

In the present embodiment, the CPU 113 calculates the correction amount ΔT of the time interval with respect to the pulse interval based on the pulse count number.
In the present embodiment, the pulse count number N ₀ (N ₀ is an integer of 2 or more) in a normal temperature environment (for example, temperature T ₀ ) and the distance interval F are stored in advance in a storage unit (not shown). ing. For example, the distance interval F is expressed by the following equation (1).

F = G / N ₀ (1)

For example, if the pulse count number N ₀ is 10,000 pls (pieces; pulses) and the distance G is 1000 mm, the distance interval F = 1000 mm / 10000 pls = 100 μm (micrometer).
The CPU 113 calculates the pulse count number N by moving the carriage 7 by the distance G (scan width). At this time (for example, the temperature T ₁ ), the distance interval L is expressed by the following equation (2).

  L = G / N (2)

  For example, if the pulse count number N is 9900 pls and the distance G is 1000 mm, the distance interval F = 1000 mm / 9900 pls = 101 μm. That is, when correction is not performed, an error of ΔL = 1 μm per pulse occurs.

  Here, the detection pulse KP arrives at time intervals according to the transport speed V. The time interval S in the normal temperature environment and the time interval T at the time of detection are expressed by the following equations (3) and (4), respectively.

S = F / V (3)
T = L / V (4)

  Therefore, the correction time interval Th (= time interval S) is expressed by the following equation (5), and the correction amount ΔT is expressed by the following equation (6).

Th = S = F / V = T × (F / L) (5)
ΔT = T−Th = T × {1− (F / L)} (6)

  That is, the CPU 113 calculates the distance interval L using the equation (2) based on the acquired pulse count number N and the distance G stored in advance. The CPU 113 calculates the correction amount ΔT using the equation (6) based on the calculated distance interval L, the distance interval F stored in advance, and the detected time interval T. Note that the CPU 113 may store the transport speed V in advance and calculate T using equation (4).

Note that the CPU 113 may calculate the correction amount ΔT using the following equation (7) based on the acquired pulse count number N, the pulse count number N ₀ stored in advance, and the detected time interval T. .

ΔT = T × {1− (N / N ₀ )} (7)

Thereby, the droplet discharge device 1 can correct the deviation amount ΔL. For example, in order to correct the shift amount ΔL, the distance interval L between the dots Dt shown in FIG. 13A may be set to the distance interval F. Therefore, the time interval T shown in FIG. S may be used. In order to correct the time interval T to the time interval S, ΔT, which is the time corresponding to the shift amount ΔL, may be used as the correction amount.
In FIG. 13 showing an example in which the linear scale 71 is extended, the time obtained by subtracting the correction amount ΔT from the time interval T is the time interval S. Therefore, the droplet 55 is ejected every time the correction amount ΔT is subtracted from the time interval T. You can do it. Thereby, the distance interval L can be corrected to the distance interval F.

As described above, the CPU 113 generates the correction signal HS. The correction signal HS includes data indicating the correction amount ΔT. The correction signal HS is input to the ejection timing signal generator 171 as shown in FIG. An encoder signal EP is also input to the discharge timing signal generation unit 171. The ejection timing signal generation unit 171 outputs the ejection timing signal TS obtained by correcting the time interval T in the encoder signal EP based on the correction signal HS to the head drive control unit.
At this time, as shown in FIG. 14, the ejection timing pulse TP (k) appears in the ejection timing signal TS at the correction time interval Th. The correction time interval Th is a time obtained by correcting the time interval T in the encoder signal EP to the time interval S. That is, in the example in which the linear scale 71 is extended, the time obtained by subtracting the correction amount ΔT from the time interval T is the correction time interval Th.

In the present embodiment, the first ejection timing pulse TP (1) is output, for example, after the first detection pulse KP (1) is output, the third detection pulse KP (3) is output. Delay until.
The ejection timing signal TS is input to the head drive controller 171 as shown in FIG. The head drive control unit 171 to which the ejection timing signal TS is input outputs the ejection timing signal TS to the head drive circuit 175 when the drawing command signal IS is in an on state.
The head driving circuit 175 permits the ejection head 33 to eject the droplet 55 every time the ejection timing pulse TS of the ejection timing signal TS rises. Thereby, as shown in FIG. 14, the dots Dt can be formed at the distance interval F.

Next, the operation of the droplet discharge device 1 in this embodiment will be described.
FIG. 15 is a flowchart showing the drawing process in this embodiment.
(Step S <b> 101) The CPU 113 moves the carriage 7 to move the encoder 73 to the reference starting point. Thereafter, the CPU 113 starts moving toward the detection position. As a result, the encoder signal EP is input from the encoder 73 to the CPU 113. The CPU 113 detects the detection pulse KP from the encoder signal EP and counts the number thereof. Then, it progresses to step S102.

(Step S102) When the carriage 7 moves by the distance G (scan width), that is, when the encoder 73 reaches the detection position, the carriage 113 receives the carriage detection signal CP from the reference sensor S1. The CPU 113 sets the number of pulses KP counted until the carriage detection signal CP is input as the pulse count number N. That is, the CPU 113 counts the pulse count number N. Thereafter, the process proceeds to step S103.

(Step S103) The CPU 113 calculates a correction time interval Th and calculates a correction amount ΔT. The CPU 113 generates a correction signal HS indicating the calculated correction amount ΔT. Thereafter, the process proceeds to step S104.
(Step S104) The ejection timing signal generator 171 corrects the encoder signal EP based on the correction amount ΔT indicated by the correction signal HS generated in step S103. Thereafter, the process proceeds to step S105.

(Step S105) The ejection timing signal generation unit 171 generates the ejection timing signal TS as a result of the correction in Step S104. The discharge timing signal TS is a signal that causes a discharge timing pulse to rise every correction time interval Th. The discharge timing signal generation unit 171 outputs the generated discharge timing signal TS. Thereafter, the process proceeds to step S106.
(Step S106) The head drive control unit 173 drives the head based on the ejection timing signal TS output in step S105. Specifically, the head drive control unit 173 outputs the ejection timing signal TS to the head drive circuit 175. The head drive circuit 175 drives the ejection head 33 based on the inputted ejection timing signal TS, and ejects the droplet 55 from the nozzle 37 at the timing when the ejection timing pulse rises. Thereafter, the operation is terminated.

Thus, in the droplet discharge device 1 (drawing device) in this embodiment, the carriage transport device 11 (displacement unit) displaces the discharge head 33 that discharges the liquid material. The linear scale 71 is provided with a plurality of scales arranged along the direction of displacement. The encoder 73 (first detection unit) detects the scale as the ejection head 33 is displaced. The reference sensor S1 (second detection unit) detects head position information indicating the position of the ejection head 33. The control unit 111 controls the timing at which the ejection head ejects the liquid material based on the number of scales detected by the encoder 73 and the head position information detected by the reference sensor S1.
Thereby, the droplet discharge device 1 can correct the distance interval L having the deviation amount ΔL from the distance interval F to the distance interval F. That is, the droplet discharge device 1 can correct the displacement amount of the carriage 7. In this embodiment, since the droplet 55 is ejected from the ejection head 33 based on the corrected displacement amount of the carriage 7, the positional accuracy of the dots Dt formed on the workpiece W by the droplet 55 can be improved. it can. As a result, even if the linear scale 71 is expanded or contracted, the positional accuracy of the dots Dt can be increased, so that the drawing quality on the workpiece W can be improved.
In the present embodiment, the displacement of the displacement of the carriage 7 due to the expansion and contraction of the linear scale 71 can be corrected without detecting the temperature, so that the configuration and time for detecting the temperature are omitted. Can do.

  In the droplet discharge device 1, the control unit 111 calculates the timing correction amount ΔT based on the number of scales detected by the encoder 73 and the head position information detected by the reference sensor S1. Further, the reference sensor S1 detects that the ejection head 33 has reached a predetermined detection position, and the control unit 111 detects that the control unit 111 has detected the encoder 73 until the ejection head 33 reaches the detection position. Based on the number of scales, a timing correction amount ΔT is calculated.

  Next, a modification of this embodiment will be described. The following modifications differ in the detection positions and the number of detection positions compared to the above embodiment.

(Modification 1)
In the first modification of the above embodiment, the carriage position detection device 65 is provided with a reference sensor S2 as shown in FIG. Here, the reference sensor S2 is provided so that the distance G2 from the reference start point to the detection position is smaller than the scan width. The configuration of the reference sensor S2 is the same as the configuration of the reference sensor S1. Further, the distance G2 may be larger than the scan width. That is, the distance G2 may be different from the scan width. In the first modification, the CPU 113 calculates the correction amount ΔT using the distance G2 instead of the distance G. Further, the pulse count number is the number of appearances of the detection pulse from the reference starting point to the detection position, that is, in the first modification, the number of detection pulses when the carriage 7 moves the distance G2.
Thus, in this modification, the position (or detection position) of the reference sensor S2 can be freely arranged. Further, for example, in this modification, ink can be ejected to an accurate position without being affected by a positional deviation in manufacturing or a design change of the position. Thereby, the droplet discharge apparatus 1 in the modification 1 can improve drawing quality.

(Modification 2)
In the second modification of the above embodiment, the carriage position detection device 65 is provided with a plurality of reference sensors S3m (m = 1, 2, 3) as shown in FIG. That is, the droplet discharge device 1 according to the second modification detects that the encoder 73 has reached each of a plurality of predetermined detection positions. Hereinafter, the detection position detected by the reference sensor S3m is also referred to as an m-th detection position. A section from a reference starting point (also referred to as a first reference starting point) to the first detection position is referred to as a first section, and the distance of this section is represented by G31 as shown in FIG. Similarly, a section from the (m−1) th detection position (also referred to as the mth reference starting point) to the mth detection position is referred to as the mth section, and the distance of this section is represented by G3m as shown in FIG. Further, the number of detected pulses (in the m-th section) from the m-th reference starting point to the m-th detection position is also referred to as an m-th pulse count number Nm.
The reference sensor S3m generates a carriage detection signal CPm (m = 1, 2, 3) indicating that the encoder 73 has reached the m-th detection position, and outputs the generated carriage detection signal CPm to the CPU 113.

The CPU 113 calculates the correction amount ΔTm (m = 1, 2, 3) in the corresponding section based on the plurality of pulse count numbers.
In the second modification, the m-th pulse count number Nm ₀ (Nm ₀ is an integer of 2 or more) in a room temperature environment (for example, temperature T ₀ ) and the distance interval Fm are stored in advance in a storage unit (not shown). It is remembered. For example, the distance interval F is expressed by the following equation (8).

Fm = G3m / Nm ₀ (8)

  The CPU 113 calculates the distance interval Lm in the m-th section using the equation (9) based on the acquired pulse count number N and the distance G3m stored in advance.

  Lm = G3m / Nm (9)

  The CPU 113 calculates the correction amount ΔTm in the m-th section using the equation (10) based on the calculated distance interval Lm, the distance interval Fm stored in advance, and the detected time interval Tm.

  ΔTm = Tm−Th = Tm × {1− (Fm / Lm)} (10)

As described above, in the droplet discharge device 1 according to the second modification, the plurality of reference sensors S3m (second detection unit) have the (m−1) th detection position (the mth reference start point) determined in advance by the discharge head 33. And reaching the m-th detection position. The control unit 111 determines the timing of the m-th section based on the number of scales detected by the encoder 73 until the ejection head 33 reaches the (m−1) th detection position from the (m−1) th detection position. A correction amount ΔTm (for example, ΔT2) is calculated for a plurality of m.
Thereby, the droplet discharge device 1 in the modification 2 can correct the shift amount ΔLm in the m-th section. That is, the droplet discharge device 1 according to Modification 2 can correct the discharge timing for the discharge head 33 based on the temperature of each section, for example, even if the temperature of the linear scale 71 varies depending on the position.

In the present embodiment (including modifications), the step of calculating the correction amount ΔT can be appropriately performed.
For example, if the correction amount ΔT is calculated every time drawing is performed on one work W, the positional accuracy of the dots Dt can be easily maintained in a high state for each work W.
Further, for example, by calculating the correction amount ΔT each time the carriage 7 intersects the work W, it is possible to easily suppress the variation in the positional accuracy of the dots Dt within one work W.
Timing for calculating the correction amount ΔT according to a change in environmental temperature due to an elapsed time when the droplet discharge device 1 is operated, a characteristic of a temperature change in the environment where the droplet discharge device 1 is placed, climate change, and the like. Is preferably determined. Thereby, since the frequency which calculates correction amount (DELTA) T can be set appropriately, it can make it easy to suppress the fall of drawing efficiency, maintaining the drawing quality with respect to the workpiece | work W. FIG.

In this embodiment, a form in which the one end 78a side of the linear scale 71 is supported by the screw 82 is adopted, but the support form on the one end 78a side is not limited to this. As a support form on the one end 78a side, for example, a form in which a hook-like hook is provided on the gantry 61 and a through hole formed on the one end 78a side of the linear scale 71 is hooked on this hook may be employed. In this embodiment, since the screw 82 can be omitted, the labor for fastening the screw 82 can be omitted. In addition to these, for example, a clip is provided on the gantry 61 and the one end 78a side of the linear scale 71 is clamped by this clip, and various other supports such as adhesion, welding, caulking, etc. A form may be employed.
Moreover, in this embodiment, although the form which provides tension | tensile_strength to the linear scale 71 with the tension spring 83 is employ | adopted, the provision form of tension | tensile_strength is not limited to this. As a form of applying tension, for example, a form of applying tension with various elastic bodies such as a rubber material may be employed.

In the present embodiment, an ink jet method is employed as a method for drawing. However, the drawing method is not limited to this. As a drawing method, for example, a dispensing method in which the functional liquid 53 is applied to the workpiece W using a syringe, a dispenser, or the like may be employed.
In the present embodiment, a method of calculating the shift amount ΔL based on the result of the counting process for counting the number of the scales 75 at the distance G is employed. However, the method of calculating the amount of deviation ΔL is not limited to this, and a method of calculating the amount of deviation ΔL using the amount of expansion / contraction after grasping the amount of expansion / contraction of the linear scale 71 based on the result in the counting step. Can also be employed.

In this embodiment, an example in which the configuration of the linear scale 71 and the encoder 73 is applied to the carriage position detection device 65 is shown, but the application of the configuration of the encoder 73 is not limited to the carriage position detection device 65. The configurations of the encoder 73 and the hidden member 91 can also be applied to the table position detection device 27. If the configuration of the encoder 73 is applied to the table position detection device 27, the position system of the workpiece W can be enhanced.
Furthermore, if the configuration of the encoder 73 is applied to both the carriage position detection device 65 and the table position detection device 27, the drawing quality on the workpiece W can be further improved.

  In the present embodiment, the conveyance speed V may be an average speed of the conveyance speed until the encoder 73 moves from the reference start point to the detection position.

DESCRIPTION OF SYMBOLS 1 ... Droplet discharge apparatus (drawing apparatus), 3 ... Work conveying apparatus, 7 ... Carriage, 11 ... Carriage conveying apparatus (displacement part), 23a ... Guide rail, 23b ... Guide rail, 25 ... Work table, 27 ... Table position Detecting device 33 ... Discharge head 53 ... Functional liquid 55 ... Droplet 61 ... Mounting frame 63 ... Guide rail 65 ... Carriage position detecting device 71 ... Linear scale 71a ... Main body 73 ... Encoder (first (Detection unit), 75 ... scale, 78a ... one end, 78b ... the other end, 81 ... spacer, 82 ... screw, 83 ... tension spring, 84 ... spacer, 85 ... screw, 111 ... control unit, 113 ... CPU, 115 ... drive Control unit 121 Carriage transport motor 123 Work transport motor 145 Head control unit 171 Discharge timing signal generation unit 17 ... drive control unit, 175 ... head drive circuit, S1, S2, S31 to S33 ... reference sensor (second detecting unit), W ... workpiece

Claims (5)

A displacement portion for displacing the ejection head for ejecting the liquid material;
A scale provided with a plurality of scales arranged along the direction of the displacement;
A first detector that detects the scale in accordance with the displacement of the ejection head;
A second detector for detecting head position information indicating the position of the ejection head;
A control unit that controls the timing at which the ejection head ejects the liquid material based on the number of scales detected by the first detection unit and the head position information detected by the second detection unit;
A drawing apparatus comprising:   The drawing device according to claim 1, wherein the control unit calculates the correction amount of the timing based on the number of scales detected by the first detection unit and head position information detected by the second detection unit. . The second detection unit detects that the ejection head has reached a predetermined position;
The said control part calculates the correction amount of the said timing based on the number of the scales which the said 1st detection part detected until the said discharge head arrives at a predetermined position. The drawing apparatus described in 1. The second detection unit detects that the ejection head has reached a predetermined first position and a second position;
The control unit calculates the correction amount of the timing based on the number of scales detected by the first detection unit until the ejection head reaches the second position from the predetermined first position. The drawing apparatus according to any one of claims 1 to 3. A drawing method in a drawing apparatus,
A displacement process in which the drawing apparatus displaces an ejection head that ejects a liquid; and
A first detection step of detecting a plurality of scales arranged along the direction of the displacement in accordance with the displacement of the ejection head;
A second detection process in which the drawing apparatus detects head position information indicating a position of the ejection head;
A control process for controlling the timing at which the ejection head ejects the liquid material based on the scale detected by the drawing apparatus in the first detection process and the head position information detected in the second detection process; ,
A drawing method comprising:

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