Liquid ejection device and liquid ejection method

Abstract

To provide a liquid discharge device which can prevent collision between an object and a liquid discharge unit while discharging a liquid.SOLUTION: A liquid discharge device includes a liquid discharge port for discharging a liquid to an object, and a liquid discharge unit which can move at least in one direction out of a first direction and a second direction intersecting the first direction, and a third direction intersecting the first direction and the second direction and parallel to a direction for discharging the liquid. The liquid discharge device includes position detection means which detects a position of the liquid discharge unit to the object, and control means which controls movement of the liquid discharge unit. The control means calculates a movement locus when the liquid discharge unit discharges the liquid to the object after the position detection means detects the position of the liquid discharge unit to the object, and carries out first operation for moving the liquid discharge unit along the calculated movement locus before the liquid discharge unit discharges the liquid to the object.SELECTED DRAWING: Figure 19

Description

Technical Field

[0001] The present invention relates to a liquid ejection device and a liquid ejection method.

Background Art

[0002] Patent Document 1 describes an apparatus for ejecting a liquid, comprising a carriage 5 having a recording head 10 for ejecting a liquid, and scanning means for scanning the carriage 5 in a main scanning direction. The carriage 5 has a jam detection sensor 16 for detecting contact with a recording medium P, and lifting means for moving the recording head 10 to vary the distance between the recording head 10 and the recording medium P. When the detection means detects contact, the scanning means stops scanning the carriage 5 and the lifting means simultaneously increases the distance between the recording head 10 and the recording medium P.

Summary of the Invention

Problems to be Solved by the Invention

[0003] An object of the present invention is to provide a liquid ejection device capable of preventing collision between an object and a liquid ejection unit during liquid ejection.

Means for Solving the Problems

[0004] The present invention is a liquid ejection device comprising a liquid ejection port for ejecting a liquid toward an object, and a liquid ejection unit movable in at least one of a first direction and a second direction intersecting the first direction, and in a third direction intersecting the first and second directions and parallel to the direction in which the liquid is ejected from the liquid ejection port toward the object, the liquid ejection device comprising position detection means for detecting the position of the liquid ejection unit with respect to the object Contact detection unit having the same and control means for controlling the movement of the liquid ejection unit. The liquid ejection unit is movable between an ejection position for ejecting the liquid toward the object and a standby position that is farther away from the object than the ejection position in the third direction. The contact detection unit is mounted so as to cover the liquid ejection port of the liquid ejection unit in a state where the liquid ejection unit is in the standby position. After the position detection means detects the position of the liquid discharge unit with respect to the object, the control means calculates a movement locus when the liquid discharge unit discharges liquid onto the object, and before the liquid discharge unit discharges liquid onto the object, the control means performs a first operation of moving the liquid discharge unit along the calculated movement locus.

Advantages of the Invention

[0005] According to the present invention, it is possible to provide a liquid discharge device capable of preventing collision between an object and a liquid discharge unit during liquid discharge.

Brief Description of the Drawings

[0006]

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Embodiments for Carrying Out the Invention

[0007] Embodiments of the present invention will be described below with reference to the drawings.

[0008] FIG. 1 is an overall schematic configuration diagram of the liquid ejection device of the present invention. FIG. 1(a) is a side view of the liquid ejection device, and FIG. 1(b) is a plan view of the same device.

[0009] The liquid ejection device 1000 is installed facing the object to be drawn, the drawn object 100. The liquid ejection device 1000 includes an X-axis rail 101, a Y-axis rail 102 that intersects the X-axis rail 101, and a Z-axis rail 103 that intersects the X-axis rail 101 and the Y-axis rail 102. The Y-axis rail 102 holds the X-axis rail 101 so that the X-axis rail 101 can move in the Y-axis direction. The X-axis rail 101 holds the Z-axis rail 103 so that the Z-axis rail 103 can move in the X-axis direction. And the Z-axis rail 103 holds the carriage 70 so that the carriage 70 can move in the Z-axis direction.

[0010] Here, the X-axis is an example of the first direction. Also, the Y-axis is an example of the second direction that intersects the first direction. Also, the Z-axis is an example of the third direction that intersects the first direction and the second direction. The carriage 70 is an example of a liquid ejection unit, and the carriage 70 includes a head 300 for ejecting ink, which is an example of a liquid, toward the drawn object 100.

[0011] The carriage 70 includes a Z-direction drive unit 92 that drives the carriage 70 in the Z-axis direction along the Z-axis rail 103. The Z-axis rail 103 includes an X-direction drive unit 72 that drives the Z-axis rail 103 in the X-axis direction along the X-axis rail 101. Further, the X-axis rail 101 includes a Y-direction drive unit 82 that drives the X-axis rail 101 in the Y-axis direction along the Y-axis rail 102.

[0012] With the above configuration, the liquid ejection device 1000 ejects ink from the head 300 toward the drawn object 100 while moving the carriage 70 in the X-axis, Y-axis, and Z-axis directions based on the drawing data, and performs drawing on the drawn object 100.

[0013] Note that the movement of the carriage 70 in the Z-axis direction does not have to be parallel to the Z-axis, and may be an oblique movement as long as it includes at least a component in the Z-axis direction.

[0014] Also, the object to be drawn 100 is not limited to a flat surface. The object to be drawn 100 may be a surface close to vertical or a surface with a large radius of curvature, such as the body of a car, a truck, or an aircraft.

[0015] Next, the configuration of the carriage 70 will be described.

[0016] FIG. 2 is a perspective view showing a state where the carriage is at the standby position on the Z-axis.

[0017] The carriage 70 is movable in the Z-axis direction along the Z-axis rail 103 by the power from the Z-direction drive unit 92.

[0018] The carriage 70 includes a head fixing plate 7 for attaching the head 300. FIG. 2 shows an example of mounting the yellow head 300Y, the magenta head 300M, the cyan head 300C, the black head 300K, the white head 300W, and the special color head 300S on the head fixing plate 7. Hereinafter, when these heads are collectively referred to, they are denoted as the head 300.

[0019] Each of the heads 300Y, 300M, 300C, 300K, 300W, and 300S includes a nozzle surface 302a having a plurality of nozzles 302.

[0020] Here, the nozzle 302 is an example of a liquid discharge port, and the nozzle surface 302a is an example of a liquid discharge surface.

[0021] Note that the types and numbers of the colors of the ink used in the head 300 are not limited to the above. For example, all the ink used in the head 300 may be the same color.

[0022] The head 300 is fixed to the head fixing plate 7 in a state where the nozzle surface 302a intersects the horizontal plane (X-Z plane) and the arrangement direction of the plurality of nozzles 302 is inclined with respect to the X-axis. Thereby, the nozzles 302 discharge ink in a direction (Z direction) intersecting the gravitational direction.

[0023] In addition, in FIG. 2, reference numeral 4 denotes a cleaning unit for cleaning the head 300.

[0024] The cleaning unit 4 moves in a direction parallel to the X-axis along the guide rail 9R fixed to the frame body 80.

[0025] Although not shown, inside the frame body 80, a motor for moving the cleaning unit 4 along the guide rail 9R, a position sensor for detecting the position of the cleaning unit 4 on the X-axis (standby position, turning position), etc. are arranged.

[0026] Thereby, the motor transmits power to the belt 14 shown in FIG. 2, and the cleaning unit 4 connected to the belt 14 moves in the positive X-axis direction along the guide rail 9R.

[0027] Then, the cleaning unit 4 cleans the nozzle surface 302a and the nozzles 302. When the cleaning unit 4 further moves in the positive X-axis direction and reaches the turning position, the moving direction switches to the negative X-axis direction, and the cleaning unit 4 returns to the standby position.

[0028] FIG. 3 is a perspective view showing a state where the carriage is at the ink discharge position on the Z-axis.

[0029] The point that the carriage 70 is moving toward the object to be drawn 100 side (positive Z-axis direction) is different from FIG. 2.

[0030] The carriage 70 moves on the Z-axis between the ink discharge position (FIG. 3) where ink is discharged from the head 300 toward the object to be drawn 100 and the standby position (FIG. 2) provided at a position away from the object to be drawn 100 with respect to the ink discharge position.

[0031] Note that the ink ejection position of the carriage 70 is not constant but variable based on the drawing data.

[0032] FIG. 4 is a perspective view showing a state in which a contact detection unit is attached to the carriage.

[0033] The contact detection unit 200 includes a first detection member 210 that is detachable from the carriage 70 and a second detection member 220 that is detachable from the first detection member 210.

[0034] Here, the first detection member 210 is an example of a first member, and the second detection member 220 is an example of a second member. Hereinafter, the configuration of the contact detection unit 200 will be described in detail.

[0035] FIG. 5 is a plan view of the vicinity of the head of the carriage. FIG. 5(a) shows a state in which the contact detection unit is not attached, and FIG. 5(b) shows a state in which the contact detection unit is attached to the carriage.

[0036] The contact detection unit 200 includes a first detection member 210 that is detachable from the carriage 70 and a second detection member 220 that is detachable from the first detection member 210.

[0037] The first detection member 210 includes locking members 211a and 211b, and these locking members 211a and 211b are detachable from an attachment portion (not shown) provided on the carriage 70. Thereby, the contact detection unit 200 is detachable from the carriage 70.

[0038] In addition, a head protection member 212 corresponding to the position of each nozzle 302 of the head 300 is provided at the opposing portion of the first detection member 210 with the head 300. The head protection member 212 covers each nozzle 302 during the period when the contact detection unit 200 is attached to the carriage 70, and prevents drying of the nozzles 302 and attachment of foreign matter to the nozzles 302.

[0039] FIG. 6 is a plan view of the contact detection unit.

[0040] The members described in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted.

[0041] The first detection member 210 includes push switches 213a, 213b, 213c, and 213d. Hereinafter, when these push switches are collectively referred to, they are denoted as push switch 213. The push switch 213 is a switch that operates in response to the movement of the second detection member 220 mounted on the first detection member 210.

[0042] The push switch 213 is configured to operate by the pressing force received from the second detection member 220 when the second detection member 220 moves in the negative Z-axis direction in the position measurement of the surface of the object to be drawn 100. Details of the position measurement will be described later.

[0043] Here, the push switch 213 is an example of the position detection means.

[0044] FIG. 7 is a perspective view of the contact detection unit from the back side.

[0045] The members already described in FIGS. 5 and 6 etc. are denoted by the same reference numerals, and the description thereof is omitted.

[0046] The head protection member 212 provided on the first detection member 210 corresponds to the positions of the nozzles 302 of the head 300 as shown in the figure, and is made of an elastic body such as sponge or rubber.

[0047] FIG. 7 shows a configuration in which 48 (8×6) head protection members 212 corresponding to 48 nozzles 302 are provided. During the period when the contact detection unit 200 is mounted on the carriage 70, the head protection member 212 covers each nozzle 302 of the head 300 and prevents the nozzles 302 from drying and foreign matter from adhering to the nozzles 302.

[0048] Note that the number and arrangement of the nozzles are not limited to the above. The nozzles may be a nozzle row arranged in a single column vertically or horizontally, rather than a two-dimensional array vertically and horizontally as shown in the figure. Also, the number of nozzles may be one instead of a plurality.

[0049] FIG. 8 is an explanatory view of the first detection member and the second detection member of the contact detection unit. FIGS. 8(a) and 8(b) show the first detection member, FIG. 8(a) is a front view of the member, and FIG. 8(b) is a perspective view from the front direction of the member. FIGS. 8(c) and 8(d) show the second detection member, FIG. 8(c) is a rear view of the member, and FIG. 8(d) is a perspective view from the rear direction of the member.

[0050] As shown in FIGS. 8(a) and 8(b), the first detection member 210 includes magnets 214a, 214b, 214c, 214d which are an example of means for generating a magnetic force on the front surface portion. The first detection member 210 also includes detection plates 215a, 215b on the front surface portion. Further, the first detection member 210 includes lock members 211a, 211b used when mounting on the carriage 70. Hereinafter, when these magnets are collectively referred to, they are denoted as magnet 214.

[0051] On the other hand, as shown in FIGS. 8(c) and 8(d), the second detection member 220 includes magnets 224a, 224b, 224c, 224d which are an example of means for generating a magnetic force on the rear surface portion. The second detection member 220 also includes leaf springs 225a, 225b having conductivity on the rear surface portion. Hereinafter, when these magnets are collectively referred to, they are denoted as magnet 224.

[0052] Then, the first detection member 210 and the second detection member 220 are mounted such that the front surface portion of the first detection member 210 faces the rear surface portion of the second detection member 220. The mounting of the second detection member 220 to the first detection member 210 is performed by the magnetic force of the magnet 214 and the magnet 224 described above.

[0053] The surface of the magnet 214 of the first detection member 210 protrudes slightly more than the surrounding surface (the surface where the magnet 214 is not installed). On the other hand, the surface of the magnet 224 of the second detection member 220 is slightly lower than the surrounding surface (the surface where the magnet 224 is not installed). As a result, the magnets 214 and 224 form unevenness, and when the second detection member 220 is attached to the first detection member 210, the relative positions of the first detection member 210 and the second detection member 220 are determined at one location, making it easier to position.

[0054] Also, when the second detection member 220 is attached to the first detection member 210, the leaf springs 225a of the second detection member 220 are in contact with the detection plate 215a of the first detection member 210. Also, the leaf springs 225b of the second detection member 220 are in contact with the detection plate 215b of the first detection member 210.

[0055] FIG. 9 is a perspective view of the first detection member and the second detection member.

[0056] The first detection member 210 and the second detection member 220 are attached by the magnetic force of the magnets 214 and 224 provided on both of them as described above. The magnetic force here is set to such a strength that it enables relative movement between the first detection member 210 and the second detection member 220 when an external force F is applied to the side surface of the second detection member 220 from the direction of the arrow as shown in the figure.

[0057] The above relative movement is used when the second detection member 220 detects obstacles such as protrusions existing on the surface of the object to be drawn 100 in the verification of the position information of the object to be drawn 100 described later. When the second detection member 220 moves with respect to the first detection member 210, the leaf springs 225a and 225b of the second detection member 220 separate from the detection plates 215a and 215b of the first detection member 210 and output an electrical signal.

[0058] Here, the detection plates 215a and 215b are an example of obstacle detection means.

[0059] FIG. 10 is an explanatory diagram of the electrical connection relationship of the contact detection unit. FIG. 10(a) is a schematic diagram showing the electrical connection relationship in the plane direction of the contact detection unit, and FIG. 10(b) is a schematic diagram showing the electrical connection relationship in the front direction of the unit.

[0060] The first detection member 210 is mounted on the carriage 70 having the head 300 by the lock members 211a and 211b (see FIG. 6). When the first detection member 210 is mounted on the carriage 70, the pin-shaped connection terminals 216a and 216b provided on the first detection member 210 are fitted into the jacks provided on the carriage 70, electrically connecting the first detection member 210 and the carriage 70.

[0061] The second detection member 220 is mounted on the first detection member 210 by the magnetic forces of the magnets 214 and 224. When the second detection member 220 is mounted on the first detection member 210, the detection plates 215a and 215b of the first detection member 210 and the leaf springs 225a and 225b of the second detection member 220 are in contact, electrically connecting the two detection members 210 and 220.

[0062] The detection plate 215a of the first detection member 210 is electrically connected to the connection terminal 216a via the push switches 213a and 213b. Also, the other detection plate 215b is electrically connected to the connection terminal 216b via the push switches 213d and 213c. Hereinafter, when these push switches are collectively referred to, they are denoted as push switch 213.

[0063] As described above, the push switch 213, the detection plates 215a and 215b provided on the first detection member 210, and the leaf springs 225a and 225b provided on the second detection member 220 are connected in series to form a series connection circuit.

[0064] In the in-line connection circuit, when the first detection member 210 and the second detection member 220 are mounted on the carriage 70 at correct positions, it is configured to be electrically conductive. For example, the push switch 213 is on (conductive state) when not pressed and off (non-conductive state) when pressed.

[0065] When the push switch 213 is in the conductive state, it is detected that the first detection member 210 and the second detection member 220 are in the correct positions, and when in the non-conductive state, it is detected that the first detection member 210 or the second detection member 220 is not in the correct position.

[0066] Note that the configuration of the detection means is not limited to the above. Instead of contact-type detection means such as push switches and detection plates, non-contact detection means such as optical sensors may be used. Also, the number and arrangement of the detection means are not limited to the above. Depending on the size of the carriage 70 and the head 300, etc., it may be configured with an appropriate number and arrangement.

[0067] As described above, the push switch 213 used for position detection and the detection plates 215a and 215b used for obstacle detection are detachably provided on the carriage 70.

[0068] Thereby, when the push switch 213 and the detection plates 215a and 215b are unnecessary, they can be removed from the carriage 70, so that accidental damage to the push switch 213 and the detection plates 215a and 215b can be prevented.

[0069] Also, as described above, the push switch 213 and the detection plates 215a and 215b are integrally provided as a contact detection unit 200.

[0070] Thereby, the attachment and detachment of the push switch 213 and the detection plates 215a and 215b to and from the carriage 70 can be easily performed. Also, different types of detections can be realized with one contact detection unit 200.

[0071] FIG. 11 is a block diagram of a portion related to the movement control of the carriage.

[0072] The liquid ejection device 1000 includes a carriage 70, an X-direction drive unit 72, a Y-direction drive unit 82, a Z-direction drive unit 92, a contact detection unit 200, a control unit 500, a storage unit 501, a display unit 502, and an operation panel 503.

[0073] The carriage 70 is movable in the X-axis, Y-axis, and Z-axis directions with respect to the object to be drawn 100, and the carriage 70 includes a head 300 (see FIG. 1) that ejects ink toward the object to be drawn 100.

[0074] The X-direction drive unit 72 drives the carriage 70 in the X-axis direction based on an instruction from the control unit 500. The Y-direction drive unit 82 drives the carriage 70 in the Y-axis direction based on an instruction from the control unit 500. The Z-direction drive unit 92 drives the carriage 70 in the Z-axis direction based on an instruction from the control unit 500.

[0075] The contact detection unit 200 is a unit detachably provided on the carriage 70. The contact detection unit 200 is attached to the carriage 70 when measuring the position of the object to be drawn 100 prior to executing ink ejection onto the object to be drawn 100, and when verifying the position information in the position measurement.

[0076] The contact detection unit 200 forms the above-described series connection circuit by being attached to the carriage 70, and the signal output by the contact detection unit 200 is transmitted to the control unit 500 via the carriage 70.

[0077] The control unit 500 includes a CPU that controls the entire liquid ejection device 1000, and a ROM that stores programs and other fixed data for executing control of drawing operations and the like on the CPU. Further, the control unit 500 includes a RAM that temporarily stores drawing data and the like, and an I / F and the like for transmitting and receiving data and signals used when receiving drawing data and the like from a host such as a PC. Note that the control unit 500 is an example of a control means.

[0078] Further, the control unit 500 stores and reads out the detection results of the contact detection unit 200 and the like in the storage unit 501. Further, the control unit 50 controls the X-direction drive unit 72, the Y-direction drive unit 82, and the Z-direction drive unit 92 to drive the carriage 70 in the X-axis direction, the Y-axis direction, and the Z-axis direction. Further, the control unit 500 controls the ink ejection from the head 300 provided on the carriage 70.

[0079] Furthermore, when an abnormality occurs in the operation of the carriage 70, the head 300, etc., the control unit 500 displays the fact on the display unit 502 to notify the user. Further, the control unit 500 receives an instruction from the operation panel 503 and performs processing.

[0080] The storage unit 501 stores the position information (3D coordinate information) in the position measurement from the contact detection unit 200, the information in the verification of the position information, and the like.

[0081] The display unit 502 displays the content when an abnormality occurs in the liquid ejection device 1000 to notify the user.

[0082] The operation panel 503 can input values (coordinates) for specifying the drawing area 100a for the object to be drawn 100, the moving speed of the carriage 70, the distance between the head 300 and the object to be drawn 100, and the like. Further, in the operation panel 503, it is possible to specify the 3D coordinate information indicating the surface shape of the object to be drawn 100. Note that the display unit 502 and the operation panel 503 may be made to be on one screen by a touch panel or the like.

[0083] Next, the position measurement by the contact detection unit 200 will be described.

[0084] FIG. 12 is an explanatory diagram showing the relationship between the object to be drawn and the drawing area.

[0085] The object to be drawn 100 varies in size and shape, and the positional relationship between the liquid ejection device 1000 and the object to be drawn 100 changes depending on the installation state. Therefore, prior to executing ink ejection onto the object to be drawn 100, the liquid ejection device 1000 needs to grasp the position information of the surface of the object to be drawn 100.

[0086] For example, when the area to be drawn is a rectangular drawing area 100a as shown in the figure, the coordinate information of the drawing start position P1 and the drawing end position P2 is stored in the storage unit 501 of the liquid ejection device 1000. Thereby, the drawing area 100a is determined.

[0087] Note that the coordinate information in this example is XY coordinate information, but it is not limited to the above. Depending on the installation states of the liquid ejection device 1000 and the object to be drawn 100, the liquid ejection device 1000 may be tilted with respect to the object to be drawn 100, or there may be obstacles such as protrusions on the surface of the object to be drawn 100. Therefore, it is desirable to capture the coordinate information as three-dimensional coordinate information with a Z-direction component added.

[0088] The drawing area 100a is the range within which the carriage 70 provided in the liquid ejection device 1000 moves. Note that just because the drawing area 100a is the range within which the carriage 70 moves, it does not necessarily mean that drawing is performed on the entire surface of the drawing area 100a. Also, within the range where the carriage 70 can move, there may be multiple drawing areas within the same object to be drawn 100.

[0089] Also, when there are obstacles such as protrusions within the drawing area 100a, it is necessary to store the position information of the obstacles in the storage unit 501. As an example of an obstacle, when the object to be drawn 100 is the body of a truck, reinforcing ribs of the vehicle body, etc. are applicable.

[0090] Next, the position measurement operation of the drawing area 100a of the object to be drawn 100 by the contact detection unit 200 will be described.

[0091] FIG. 13 is an explanatory diagram of position measurement. FIG. 13(a) is a plan view of the contact detection unit separated from the object to be drawn, and FIG. 13(b) is a plan view of the contact detection unit in contact with the object to be drawn.

[0092] Prior to executing ink ejection onto the object 100 to be drawn, the liquid ejection apparatus 1000 performs position measurement in order to obtain the position information of the drawing area 100a of the object 100 to be drawn and grasp the surface shape of the drawing area 100a.

[0093] For position measurement, first, the carriage 70 at the standby position on the Z-axis is moved in the positive Z-axis direction toward the object 100 to be drawn.

[0094] When the detection surface 220a of the second detection member 220 comes into contact with the object 100 to be drawn, the second detection member 220 moves in the negative Z-axis direction. By this movement of the second detection member 220 in the negative Z-axis direction, the second detection member 220 presses the first detection member 210 in the negative Z-axis direction.

[0095] Next, when the first detection member 210 moves in the negative Z-axis direction, the first detection member 210 presses the push switch 213 toward the carriage 70 side. As a result, the push switch 213 is actuated, and the contact detection unit 200 detects the position of the surface of the object 100 to be drawn.

[0096] Then, the position information of the carriage 70 at this time is stored in the storage unit 501 of the liquid ejection apparatus 1000.

[0097] The above operations are performed a plurality of times from the drawing start position P1 to the drawing end position P2 of the drawing area 100a to obtain information indicating the surface shape of the drawing area 100a.

[0098] FIG. 14 is an explanatory diagram showing an example of the electrical connection state of the contact detection unit.

[0099] The push switch 213, the detection plates 215a and 215b provided on the first detection member 210, and the leaf springs 225a and 225b provided on the second detection member 220 constitute a series connection circuit.

[0100] FIG. 14 shows a state in which the push switch 213d among the four push switches detects the surface position of the object 100 to be drawn. The position and number of the operating push switches vary depending on the surface shape of the object 100 to be drawn.

[0101] In the above configuration, the push switch 213 is turned off by the pressing force associated with the detection of the surface position of the object 100 to be drawn. When the push switch 213 is turned off, the series connection circuit becomes non-conductive, and the coordinate information at that time is stored in the storage unit 501 as coordinate information indicating the surface position of the object 100 at that position.

[0102] FIG. 15 is an explanatory diagram of the case where the coordinate information of the object to be drawn is automatically acquired.

[0103] After the user sets the drawing start position P1 and the drawing end position P2 from the operation panel 503, the user sets the X grid line 100b and the Y grid line 100c with arbitrary numerical values. The settings here include the number of grid lines or the specification of the interval between grid lines.

[0104] After the X grid line 100b and the Y grid line 100c are set, the liquid ejection device 1000 measures the position of the surface of the object 100 at the intersection of the X grid line 100b and the Y grid line 100c, and automatically acquires coordinate information (three-dimensional coordinate information of XYZ).

[0105] The user can acquire the coordinate information at a fine interval or a coarse interval according to the set values of the grid lines set by the user. Also, the user may perform only the setting of the drawing start position P1 and the grid lines, and make the drawing end position P2 follow the grid. Further, when there are obstacles such as protrusions that affect the drawing within the drawing area 100a of the object 100 to be drawn, the user may specify the XY coordinates of the part and perform position measurement and add it to the coordinate information.

[0106] FIG. 16 is an explanatory diagram showing the relationship between position measurement and the surface shape of the object to be drawn. FIG. 16(a) shows the case where the surface of the object to be drawn is inclined, and FIGS. 16(b), (c), and (d) show the case where there are protrusions on the surface of the object to be drawn.

[0107] As shown in FIG. 16(a), when the object to be drawn 100 is inclined with respect to the liquid ejection device 1000, the coordinates between two points of the coordinates (Xm, Ym, Zm) and the coordinates (Xn, Yn, Zn) are obtained by proportional calculation. Accordingly, during the ink ejection operation, the carriage 70 moves along the inclination of the object to be drawn 100 so that the distance between the object to be drawn 100 and the head 300 becomes constant.

[0108] When obtained by the proportional calculation as described above, protrusions or steps existing between the coordinates (Xm, Ym, Zm) and the coordinates (Xn, Yn, Zn) as shown in FIG. 16(b) may be recognized as slopes.

[0109] Also, as shown in FIG. 16(c), when there is exactly a protrusion between the coordinates of two points, there is a possibility of overlooking the protrusion. Further, as shown in FIG. 16(d), even if the presence of the protrusion is recognized at the stage of position measurement, there may be a case where the carriage 70 cannot avoid the protrusion and collides with the protrusion.

[0110] The reason for such a problem is that the operation of the carriage 70 is different between position measurement and ink ejection.

[0111] Position measurement is performed by moving the carriage 70 in the XY direction, and after the carriage 70 is positioned at the measurement location, moving the carriage 70 in the Z direction. On the other hand, ink ejection onto the object to be drawn 100 is performed by continuously moving the carriage 70 in the XYZ directions while keeping the distance between the object to be drawn 100 and the carriage 70 constant.

[0112] Therefore, in the present invention, a step of verifying the position information in position measurement is provided after position measurement and before executing the ink ejection operation.

[0113] In this verification, the carriage 70 is moved relative to the object 100 to be drawn along the coordinate information indicating the movement locus of the carriage 70 obtained based on the position information in position measurement, and it is checked whether protrusions or the like overlooked in the position measurement appear. The operation of the carriage 70 during verification is performed in the same manner as during the ink ejection operation, except that ink ejection is not performed. Therefore, in this verification, if no new protrusions or the like appear, it is possible to prevent drawing failure during the actual ink ejection operation. Details of the verification will be described later.

[0114] FIG. 17 is an explanatory diagram showing the relationship between the detection surface of the contact detection unit and the liquid ejection surface. FIG. 17(a) shows the detection surface of the contact detection unit, and FIG. 17(b) shows the liquid ejection surface of the carriage.

[0115] In FIG. 17(a), the contact detection unit 200 attached to the carriage 70 includes a first detection member 210 and a second detection member 220. The measurement of the position relative to the object 100 to be drawn is performed by bringing the detection surface 220a of the second detection member 220 into contact with the surface of the object 100.

[0116] On the other hand, the carriage 70 is provided with a nozzle 302, which is an example of a liquid ejection port, at a portion where the contact detection unit 200 is located. In this example, a head 300 having a plurality of nozzles 302 is attached to the carriage 70.

[0117] Here, the surface formed by the nozzle 302 is referred to as the liquid ejection surface and is represented by reference numeral 302a.

[0118] FIG. 17(b) illustrates a head 300 having 48 nozzles 302 arranged in 6 rows in the Y-axis direction with 8 nozzles 302 in the X-axis direction. In the case of this example, the surface formed by these 48 nozzles 302 becomes the liquid ejection surface 302a. Alternatively, a surface having a shape corresponding to the outer shape of the head 300 may be used as the liquid ejection surface 302a.

[0119] Note that the number and arrangement of the nozzles 302 are not limited to the above. The nozzles 302 may be a nozzle array arranged in a single row vertically or horizontally, rather than a two-dimensional array vertically and horizontally as shown in the figure. Also, instead of a plurality of nozzles 302, only one nozzle may be used.

[0120] Furthermore, up to this point, an example has been described based on the case where the detection surface 220a of the second detection member 220 has an area larger than the liquid ejection surface 302a of the carriage 70. However, the height (Y-axis direction), width (X-axis direction), and thickness (Z-axis direction) of the detection surface 220a may be appropriately changed according to the surface shape and surface state of the object to be drawn 100 on which the position measurement is performed.

[0121] Here, the area of the detection surface 220a refers to the area of the projection surface obtained by projecting the detection surface 220a onto the liquid ejection surface 302a from the side of the object to be drawn 100 on the Z-axis. For example, as shown in the figure, when the detection surface 220a has an area larger than the liquid ejection surface 302a, it can be said that the liquid ejection surface 302a exists within the projection surface of the detection surface 220a from the side of the object to be drawn 100.

[0122] FIG. 18 is an explanatory diagram when the size of the detection surface of the contact detection unit is changed. FIG. 18(a) shows the case where the detection surface of the second detection member is larger than the liquid ejection surface. FIG. 18(b) shows the case where the detection surface of the same member is equal to the liquid ejection surface. FIG. 18(c) shows the case where the detection surface of the same member is smaller than the liquid ejection surface.

[0123] As shown in FIG. 18(a), when the detection surface 220a of the second detection member 220 is larger than the liquid ejection surface 302a, it becomes possible to detect a wide range at once when measuring the position of the object to be drawn 100. Therefore, it becomes possible to perform position detection on a flat object to be drawn in a short time.

[0124] As shown in FIG. 18(b), when the detection surface 220a of the second detection member 220 is equal to the liquid ejection surface 302a, it becomes possible to perform position detection at intervals corresponding to the width of the head 300.

[0125] When the detection surface 220a of the second detection member 220 is smaller than the liquid discharge surface 302a as shown in FIG. 18(c), it is possible to perform fine position detection on the object to be drawn 100. Therefore, it is possible to reduce the overlooking of obstacles such as protrusions with respect to the object to be drawn 100 having obstacles such as protrusions at narrow intervals.

[0126] Next, verification of the position information will be described.

[0127] The liquid discharge device of the present invention has a step of verifying the position information obtained by the position measurement after the position measurement and before executing the ink discharge operation.

[0128] In this verification, based on the coordinate information indicating the movement locus of the carriage 70 obtained based on the position information obtained by the position measurement, the carriage 70 is moved with respect to the object to be drawn 100 to check whether protrusions or the like overlooked during the position measurement appear. The operation of the carriage 70 during verification is performed in the same operation as during the ink discharge operation except that ink discharge is not performed.

[0129] FIG. 19 is an overall flowchart of the liquid discharge device of the present invention.

[0130] As described above, the liquid discharge device of the present invention first performs position detection of the carriage 70 with respect to the object to be drawn 100 by the contact detection unit 200 (step S101).

[0131] After detecting (measuring) the position of the carriage 70 with respect to the object to be drawn 100 in the position detection step S101, based on the position information (three-dimensional coordinate information) obtained in the position detection step S101, the movement locus when the carriage 70 discharges ink onto the object to be drawn 100 is calculated (step S102).

[0132] Next, the carriage 70 is moved along the movement locus calculated in step S102 to verify the movement locus (step S103).

[0133] During the operation of this verification step S103, it is detected whether there is an obstacle such as a protrusion on the object 100 to be drawn that collides with the carriage 70 and hinders the movement of the carriage 70 (step S104).

[0134] And in the verification step S103, if a collision with an obstacle is not detected, the execution of ink ejection onto the object 100 to be drawn is enabled (step S105).

[0135] Figure 20 is a verification flowchart of position information.

[0136] First, the carriage 70 equipped with the contact detection unit 200 moves to the drawing start position P1 set by the user on the operation panel 503 (step S1).

[0137] Next, the carriage 70 starts to move from the drawing start position P1 under the control of the control unit 500 of the liquid ejection device 1000 (step S2).

[0138] Based on the position information detected by the position detection means (push switch 213) in the position measurement, the control unit 500 determines the three-dimensional (XYZ) coordinates indicating the movement trajectory of the carriage 70. Then, according to this three-dimensional coordinate information, the control unit 500 moves the carriage 70 toward the drawing end position P2 set by the user on the operation panel 503.

[0139] During the movement of the carriage 70, the contact detection unit 200 attached to the carriage 70 detects the protrusions of the object 100 to be drawn (step S3).

[0140] If the contact detection unit 200 does not detect a protrusion while the carriage 70 moves from the drawing start position P1 to the drawing end position P2, the carriage 70 ends its movement (step 4). The details of part A of this flowchart will be described later.

[0141] If the movement of the carriage 70 is completed, the control unit 500 of the liquid ejection device 1000 notifies the user by displaying on the display unit 502 that the verification has been completed (step S5).

[0142] Then, the carriage 70 moves to the drawing start position P1 (step S6). The carriage 70 that has moved to the drawing start position P1 waits for executing ink ejection to the object to be drawn 100.

[0143] On the other hand, while the carriage 70 moves from the drawing start position P1 to the drawing end position P2, if the contact detection unit 200 detects a protrusion, the control unit 500 of the liquid ejection device 1000 records the position information indicating the position of the protrusion (step S7). The recording here is performed, for example, by storing in the storage unit 501 provided in the liquid ejection device 1000.

[0144] Next, the control unit 500 of the liquid ejection device 1000 moves the carriage 70 in the negative Z-axis direction by the Z-axis drive unit 92, and the carriage 70 moves to the standby position on the Z-axis (step S8). Thereby, the carriage 70 is in a state of retreating from the protrusion.

[0145] Further, the control unit 500 of the liquid ejection device 1000 stops the X-axis drive unit 72 and the Y-axis drive unit 82, and stops the carriage 70 (step S9).

[0146] Next, the control unit 500 of the liquid ejection device 1000 notifies the user by displaying the position information of the protrusion on the display unit 502 (step S10).

[0147] Next, the display screen of the operation panel 503 shifts to the position measurement screen (step S11).

[0148] On the position measurement screen, if necessary, the user adds the position information of the protrusion to the position information in the original position measurement. Note that the addition of the position information of the protrusion may be performed manually by the user after the user checks the state of the object 100 to be drawn and determines whether addition is necessary, or may be automatically performed on the side of the liquid ejection device 1000.

[0149] As described above, in step S3, when the contact detection unit 200 detects a protrusion, the position information of the protrusion is added to the position information in the original position measurement, and the flow is executed again from step S1. Then, while the carriage 70 moves from the drawing start position P1 to the drawing end position P2, if the contact detection unit 200 does not detect a protrusion, the verification is completed, and the process proceeds to the step of actually ejecting ink toward the object 100 to be drawn.

[0150] Note that after the verification is completed, it is not always the case that the process immediately proceeds to the execution of ink ejection. After the first verification is completed, position measurement may be performed again. By repeating the position measurement and verification of the object 100 to be drawn, the three-dimensional coordinate information of the object 100 to be drawn can be obtained more precisely, and ink ejection suitable for the shape can be performed.

[0151] In addition, since the three-dimensional coordinate information once created by position measurement and verification is stored in the storage unit 501 of the liquid ejection device 1000, when ink ejection is performed on the object 100 to be drawn having the same shape, the three-dimensional coordinate information can be used.

[0152] Also, even when the relative position between the liquid ejection device 1000 and the object 100 to be drawn changes, the coordinate information regarding the shape of the object 100 to be drawn is available. Therefore, if the objects 100 to be drawn have the same shape, the user can omit at least a part of the verification process by using the position information in the position measurement.

[0153] In addition, in the detection of the protrusion of the object 100 to be drawn, when the protrusion of the object 100 to be drawn collides with the second detection member 220 of the contact detection unit 200, the second detection member 220 is configured to detect the protrusion (details will be described later). However, the detection of the protrusion may be configured not to detect physical contact as described above, but to optically detect using laser light or the like, or to detect by image processing.

[0154] In addition, the detection target is not limited to the protrusion of the object 100 to be drawn. By adopting the configuration of detecting by the above-mentioned optical or image processing, it is also possible to make the holes provided in the object to be drawn and the portions where drawing is intentionally to be avoided (for example, the already drawn image or the masking portion) the detection targets.

[0155] As described above, the present embodiment includes a liquid ejection device 1000 including a nozzle 302 that ejects ink toward the object 100 to be drawn, and a carriage 70 that is movable in at least one of the direction of the X-axis and the direction of the Y-axis that intersects the X-axis, and in the direction of the Z-axis that intersects the X-axis and the Y-axis and is parallel to the direction in which ink is ejected from the nozzle 302 toward the object 100 to be drawn. The liquid ejection device 1000 is provided with a push switch 213 for detecting the position of the carriage 70 with respect to the object 100 to be drawn and a control unit 500 for controlling the movement of the carriage 70. After the push switch 213 detects the position of the carriage 70 with respect to the object 100 to be drawn, the control unit 500 calculates the movement trajectory when the carriage 70 ejects ink onto the object 100 to be drawn, and before the carriage 70 ejects ink onto the object 100 to be drawn, a verification operation (first operation) of moving the carriage 70 along the calculated movement trajectory is performed.

[0156] Thereby, it is possible to provide a liquid ejection device 1000 that can prevent a collision between the object 100 to be drawn and the carriage 70 during ink ejection.

[0157] Also, as described above, when a protrusion is detected on the object 100 during the verification operation, the display unit 502 is caused to display the fact that the protrusion has been detected to notify the user. When no protrusion is detected on the object 100 during the verification operation, an operation (second operation) of ejecting ink onto the object 100 is enabled.

[0158] This makes it possible to recognize protrusions overlooked in the position detection process.

[0159] FIG. 21 is an explanatory diagram showing the positional relationship of the carriage during verification and during ink ejection execution.

[0160] During verification of the position information, the carriage 70 is at the position indicated by the solid line with respect to the object 100. When executing ink ejection onto the object 100, the carriage 70 is at a position shifted by a distance L1 in the positive Z-axis direction as indicated by the broken line.

[0161] During verification, since the carriage 70 is equipped with the contact detection unit 200, the distance L1 is set in consideration of the size of the contact detection unit 200 in the Z-axis direction and the like. Therefore, when executing ink ejection onto the object 100, the control unit 500 performs ink ejection at a position corrected by the amount of the distance L1.

[0162] Also, the movement trajectory and movement speed of the carriage 70 during verification of the position information are the same as those when executing ink ejection onto the object 100.

[0163] In the case of a liquid ejection device that ejects ink onto an object such as the body of a car, truck, or aircraft, the liquid ejection device is a large system. Therefore, due to the self-weight of the carriage 70 and the respective rails 101, 102, 103 of the X-axis, Y-axis, and Z-axis, and the inertial force due to the operation of the carriage 70, the rails and the device frame may bend.

[0164] Therefore, when verifying the position information, it is desirable to perform the verification in accordance with the operation when actually executing ink ejection onto the object to be drawn 100. By making the movement trajectory and movement speed of the carriage during the verification of the position information the same as those when executing ink ejection onto the object to be drawn, the movement trajectory of the carriage 70 can be accurately verified.

[0165] As described above, in the verification operation, the carriage 70 moves at the same speed as during the ink ejection operation.

[0166] This can enhance the accuracy of the operation of the carriage 70 during ink ejection execution.

[0167] FIG. 22 is an explanatory diagram showing an example when a protrusion is detected in the verification. FIG. 22(a) shows the state before the protrusion is detected, and FIG. 22(b) shows the state where the protrusion is detected.

[0168] Suppose there is a protrusion 110 overlooked in the position measurement on the surface of the object to be drawn 100.

[0169] In the state of FIG. 22(a), the second detection member 220 is correctly mounted with respect to the first detection member 210. Therefore, the detection plates 215a, 215b of the first detection member 210 and the leaf springs 225a, 225b of the second detection member 220 are in contact, and the series connection circuit is in a conductive state.

[0170] As the carriage 70 moves in the positive X-axis direction, when the protrusion 110 comes below the carriage 70, the second detection member 220 can no longer move in the positive X-axis direction due to the collision with the protrusion 110. As a result, the detection plates 215a, 215b of the first detection member 210 and the leaf springs 225a, 225b of the second detection member 220 separate, and the series connection circuit becomes non-conductive. After the protrusion is detected, processing is performed based on the flow shown in FIG. 20.

[0171] FIG. 23 is an explanatory diagram showing an example of the electrical connection state of a series connection circuit. FIG. 23(a) shows a state where the contact detection unit is correctly attached to the carriage, and FIG. 23(b) shows a state where the second detection member of the contact detection unit is not correctly attached.

[0172] When the protrusion shown in FIG. 23(b) is detected, the state becomes the state shown in FIG. 22(b).

[0173] FIG. 24 is an explanatory diagram showing an example of the movement locus of the carriage.

[0174] The carriage 70 located at the drawing start position P1 moves in the positive X-axis direction, and when it reaches the turning position, it moves by the movement amount La in the positive Y-axis direction (line break).

[0175] After the line break, the carriage 70 moves in the negative X-axis direction, and when it reaches the turning position, it moves by the movement amount La again in the positive Y-axis direction for a line break. While repeating this operation, the carriage 70 moves to the drawing end position P2 along the movement locus shown by the arrow.

[0176] Note that if the movement amount of the line break of the carriage 70 is made constant at La, the carriage 70 may protrude outside the drawing area 100a in the final line.

[0177] If the carriage 70 protrudes outside the drawing area 100a, when the contact detection unit 200 detects a protrusion, it becomes impossible to distinguish whether the protrusion is detected inside the drawing area 100a or outside the drawing area 100a.

[0178] Therefore, it is desirable that the carriage 70 moves from the drawing start position P1 to the drawing end position P2 so as not to protrude outside the drawing area 100a. Therefore, in this example, the movement amount Lb of the carriage 70 in the final line is made smaller than the movement amount La, and the locus of the carriage 70 is controlled to coincide with the drawing end position P2.

[0179] Regarding this operation as well, it is desirable to make it the same when verifying the position information and when executing ink ejection onto the object to be drawn. Note that, instead of only changing the movement amount of the last line as described above, the movement amounts La and Lb may be made equal so that it finally fits within the drawing area 100a.

[0180] Figure 25 is a detailed flowchart of part A of the verification flow in Figure 20.

[0181] While checking the remaining amount in the Y-axis direction of the drawing area 100a so that the carriage 70 does not go outside the drawing area 100a, the number of movements and the movement amount of the carriage 70 are determined.

[0182] The carriage 70 located at the drawing start position P1 (see Figure 24) moves in the positive X-axis direction by the drive of the X-axis drive unit 72 (step S21).

[0183] As the carriage 70 moves in the positive X-axis direction, a counter that counts the number of movements in the X-axis direction adds 1 to the count value (step S22).

[0184] If the carriage 70 reaches the end point (turning position) in the positive X-axis direction, the control unit 500 determines whether there is any remaining area in the Y-axis direction of the drawing area 100a (step S23).

[0185] If there is no remaining area here, it means that the carriage 70 has reached the drawing end position P2, so the X-axis movement count is reset (step S33). Then, the movement of the carriage 70 ends.

[0186] On the other hand, if it is determined in step S23 that there is a remaining area, it is determined whether the remaining amount is equal to or greater than La (step S24).

[0187] Here, the movement amount La corresponds to the length (height) of the carriage 70 (nozzle surface 302a) in the Y-axis direction. Therefore, the fact that there is a remaining amount of La or more in the Y-axis direction of the drawing area 100a means that line breaks in the Y-axis direction are possible by the height of the carriage 70.

[0188] In step S24, when it is determined that the remaining amount is La or more, the carriage 70 moves by the movement amount La in the positive Y-axis direction by driving the Y-direction drive unit 82 (step S25).

[0189] Also, in step S24, when it is determined that the remaining amount is less than La, the carriage 70 moves by the movement amount Lb in the positive Y-axis direction by driving the Y-direction drive unit 82 (step S26). The movement amount Lb is a value smaller than the movement amount La, and is set so that the carriage 70 coincides with the drawing end position P2, as described with reference to FIG. 24.

[0190] The carriage 70 that has moved in the Y-axis direction in step S25 or step S26 then moves in the negative X-axis direction by driving the X-direction drive unit 72 (step S27).

[0191] As the carriage 70 moves in the negative X-axis direction, a counter that counts the number of movements in the X-axis direction increments its count value by 1 (step S28).

[0192] If the carriage 70 reaches the end point (turning position) in the negative X-axis direction, the control unit 500 determines whether there is any remaining area in the Y-axis direction of the drawing area 100a (step S29).

[0193] Here, when there is no remaining area in the drawing area, it means that the carriage 70 has reached the drawing end position P2. Therefore, the X-axis movement count is reset (step S33). Then, the movement of the carriage 70 ends.

[0194] On the other hand, when there is remaining area in the drawing area in step S29, it is determined whether the remaining amount is equal to or greater than La (step S30).

[0195] In step S30, when the remaining amount is equal to or greater than La, the carriage 70 moves by an amount La in the positive Y-axis direction by the drive of the Y-direction drive unit 82 (step S31).

[0196] Also, in step S30, when the remaining amount is less than La, the carriage 70 moves by an amount Lb in the positive Y-axis direction by the drive of the Y-direction drive unit 82 (step S32).

[0197] After the carriage 70 moves in the Y-axis direction in step S31 or step S32, the process returns to step S21, and the above flow is repeated until there is no remaining amount in the drawing area.

[0198] As described above, by moving the carriage 70 with respect to the drawing area 100a, the carriage 70 does not protrude outside the drawing area 100a, and position measurement, verification, and ink ejection can be accurately performed for the determined drawing area.

[0199] FIG. 26 is an explanatory diagram showing an example of a display screen of the operation panel of the liquid ejection device.

[0200] The user can input XY coordinate information for specifying the drawing start position P1 and the drawing end position P2 of the drawing area (printing range) 100a and specify the moving speed of the carriage 70 on the operation panel 503. Also, the user can specify three-dimensional coordinate information (body data) indicating the surface shape of the object to be drawn 100 and input the distance (set gap) between the head and the object to be drawn on the operation panel 503.

[0201] FIG. 27 is an explanatory diagram of a fall prevention member of the second detection member of the contact detection unit.

[0202] The first detection member 210 and the second detection member 220 that constitute the contact detection unit 200 are attached by the magnetic force of the magnet as described above.

[0203] Therefore, when the first detection member 210 and the second detection member 220 relatively move by an area equal to or larger than that of the magnet due to the detection of the protrusion, the second detection member 220 may fall from the first detection member 210, and the second detection member 220 may be damaged.

[0204] Therefore, in order to prevent the second detection member 220 from falling, the first detection member 210 and the second detection member 220 may be connected by a string-shaped member 230. As the string-shaped member 230, a string, a wire, a chain, or the like is used. Note that the string, the wire, the chain, or the like is an example of a fall prevention member.

[0205] FIG. 28 is an explanatory view of a liquid ejection device according to a modification of the present invention, and FIG. 29 is an enlarged perspective view of the liquid ejection device in the modification.

[0206] The liquid ejection device 1000 includes a linear rail 404 on which a carriage 1 reciprocates linearly, and an articulated robot 405 that moves the linear rail 404 to a predetermined position as appropriate and holds it at that position.

[0207] The articulated robot 405 includes a robot arm 405a that can move freely like a human arm by a plurality of joints, and the tip of the robot arm 405a can be moved freely and arranged at an accurate position.

[0208] As the articulated robot 405, for example, an industrial robot of a six-axis control type having six axes, that is, six joints can be used. According to the six-axis articulated robot, by previously teaching information regarding operations, the linear rail 404 can be confronted with a predetermined position of a drawn object 702 (aircraft) extremely accurately and quickly. The robot 405 is not limited to six axes, and an articulated robot having an appropriate number of axes such as five axes or seven axes can be used.

[0209] The robot arm 405a of the robot 405 is provided with a fork-shaped support member 424. A vertical linear rail 423a is attached to the tip of the left branch 424a of this support member 424, and a vertical linear rail 423b is attached to the tip of the right branch 424b so as to be parallel.

[0210] Both ends of the linear rail 404 that movably holds the carriage 1 are supported by the two vertical linear rails 423a and 423b.

[0211] The carriage 1 is provided with the head 300 described in FIG. 2 and the like, or a plurality of heads 300 that eject inks of various colors such as yellow, magenta, cyan, black, and white, or a head 300 having a plurality of nozzle rows. For each head 300 of this carriage 1 or each nozzle row of the head 300, inks of various colors are supplied from the ink tank 330.

[0212] This liquid ejection device 1000 moves the linear rail 404 to the drawing area of the object to be drawn 702 by the robot 405, and drives the head 300 while moving the carriage 1 along the linear rail 404 according to the drawing data to perform drawing.

[0213] When the drawing of one line is completed, the heads 300 of the carriage 1 are moved from one line to the next line by driving the vertical linear rails 423a and 423b.

[0214] By repeating this operation, it becomes possible to draw on the required drawing area of the object to be drawn 702. Also in the above-described modification examples, by attaching a contact detection unit to the carriage 1, performing position measurement and verification, and then executing ink ejection, the above-described effects according to the present invention can be obtained.

[0215] Next, an application example of the present invention will be described with reference to FIGS. 30 to 32. The present invention can also be applied to an unmanned aircraft 6000 such as a drone shown in FIG. 30. The unmanned aircraft 6000 controls its position based on the detection results of a detector 610 such as a distance measuring sensor mounted on itself. The unmanned aircraft 6000 includes a liquid discharge unit 620 including a head for discharging a liquid such as ink, and supplies the liquid stored in a liquid tank 630 to the liquid discharge unit 620 via a cable 640. Then, based on the above position control, the unmanned aircraft 6000 discharges a liquid from the head provided in the liquid discharge unit 620 toward an object (in this embodiment, the wall surface of a building) 100, and applies the liquid to a painted portion P of the object 100.

[0216] Further, the present invention can also be applied to an unmanned vehicle 7000 such as a wall climbing robot shown in FIG. 31. The unmanned vehicle 7000 can move by driving a roller 710 while sucking an object (in this embodiment, the wall surface of a building) 100 at the bottom of the unmanned vehicle 7000. The unmanned vehicle 7000 includes a liquid discharge unit 720 including a head for discharging a liquid such as ink, and supplies the liquid stored in a liquid tank 730 to the liquid discharge unit 720 via a cable 740. Then, the unmanned vehicle 7000 discharges a liquid from the head provided in the liquid discharge unit 720 toward an object (in this embodiment, the wall surface of a building) 100, and applies the liquid to a painted portion P of the object 100.

[0217] Furthermore, the present invention can also be applied to, for example, a painting robot 8000 that paints the body of an automobile as shown in FIG. 32. The painting robot 8000 includes a robot arm 810 that can move freely like a human arm by a plurality of joints, and a liquid discharge unit 820 that includes a head for discharging a liquid at the tip of the robot arm 810. Further, the robot arm 810 is provided with a 3D sensor 830 in the vicinity of the liquid discharge unit 820. As the painting robot 8000, an articulated robot having an appropriate number of axes such as 5 axes, 6 axes, or 7 axes can be used. The painting robot 8000 detects the position of the liquid discharge unit 820 with respect to the object (the vehicle body in this embodiment) 100 by the 3D sensor 830, and moves the robot arm 810 based on the detection result to paint the object 100.

[0218] What has been described above is an example, and the present invention has specific effects for each of the following aspects.

[0219] [Aspect 1] The first aspect includes a nozzle 302 (an example of a liquid discharge port) that discharges ink (an example of a liquid) toward a drawing object 100 (an example of an object), and at least one of the X-axis direction (an example of a first direction) and the Y-axis direction (a second direction intersecting the first direction) intersecting the X-axis, and a Z-axis direction (an example of a third direction intersecting the first and second directions and parallel to the direction of discharging ink from the nozzle 302 toward the drawing object 100) intersecting the X-axis and the Y-axis. A liquid discharge device 1000 (an example of a liquid discharge device) including a carriage 70 (an example of a liquid discharge unit) movable in the direction, and a push switch 213 (an example of a position detection means) for detecting the position of the carriage 70 with respect to the drawing object 100, and a control unit (an example of a control means) for controlling the movement of the carriage 70. The control unit 500 After the push switch 213 detects the position of the carriage 70 with respect to the object to be drawn 100, it calculates the movement trajectory when the carriage 70 discharges ink onto the object to be drawn 100, and before the carriage 70 discharges ink onto the object to be drawn 100, it performs a verification operation (an example of the first operation) of moving the carriage 70 along the calculated movement trajectory.

[0220] According to this aspect, it is possible to provide the liquid discharge device 1000 that can prevent the collision between the object to be drawn 100 and the carriage 70 during ink discharge.

[0221] [Second Aspect] In the second aspect, in the first aspect, when a protrusion 110 (an example of an obstacle) is detected on the object to be drawn 100 during the verification operation, it is characterized in that the detection of the protrusion 110 is displayed on the display unit 502 to notify the user (an example of notification).

[0222] [Third Aspect] The third aspect is characterized in that, in the first aspect or the second aspect, when a protrusion 110 is not detected on the object to be drawn 100 during the verification operation, it enables an operation (an example of the second operation) of discharging ink onto the object to be drawn 100.

[0223] According to the second aspect and the third aspect, it is possible to recognize a protrusion overlooked in the position detection step.

[0224] [Fourth Aspect] The fourth aspect is characterized in that, in any one of the first aspect to the third aspect, in the verification operation, the carriage 70 moves at the same speed as during the ink discharge operation.

[0225] According to the fourth aspect, it is possible to improve the accuracy of the operation of the carriage 70 during ink discharge execution.

[0226] [Fifth Aspect] The fifth aspect is characterized in that, in any one of the first to fourth aspects, a push switch 213 and detection plates 215a and 215b (an example of an obstacle detection means) for detecting a protrusion 110 are detachably provided on a carriage 70.

[0227] According to the fifth aspect, when the push switch 213 and the detection plates 215a and 215b are not required, they can be removed from the carriage 70, so that accidental damage to the push switch 213 and the detection plates 215a and 215b can be prevented.

[0228] [Sixth Aspect] The sixth aspect is characterized in that, in any one of the first to fifth aspects, the push switch 213 and the detection plates 215a and 215b are integrally provided as a contact detection unit 200 (an example of a contact detection unit).

[0229] According to the sixth aspect, the attachment and detachment of the push switch 213 and the detection plates 215a and 215b to and from the carriage 70 can be easily performed. Also, different types of detections can be realized with one contact detection unit 200.

Explanation of Reference Numerals

[0230] 70 Carriage (an example of a liquid ejection unit) 72 X-direction drive unit 82 Y-direction drive unit 92 Z-direction drive unit 100 Object to be drawn (an example of a target object) 101 X-axis rail 102 Y-axis rail 103 Z-axis rail 200 Contact detection unit 210 First detection member (an example of a first member) 213 Push switch (an example of a position detection means) 214 Magnet 215a, 215b Detection plates (an example of an obstacle detection means) 220 Second detection member (an example of a second member) 220a Detection surface 224 Magnet 225a, 225b Leaf springs 230 String-like member (an example of a fall prevention member) 300 Head 302 Nozzle (an example of a liquid discharge port) 302a Nozzle surface (an example of a liquid discharge surface) 500 Control unit (an example of a control means) 1000 Liquid discharge device

Prior art documents

Patent documents

[0231]

Patent Document 1

Claims

1. A liquid ejection device comprising a liquid ejection port for ejecting a liquid toward an object, and a liquid ejection unit movable in at least one of a first direction and a second direction intersecting the first direction, and in a third direction intersecting the first direction and the second direction and parallel to the direction in which the liquid is ejected from the liquid ejection port toward the object, the liquid ejection device comprising a contact detection unit having position detection means for detecting the position of the liquid ejection unit with respect to the object, and control means for controlling the movement of the liquid ejection unit, wherein the liquid ejection unit is movable between a discharge position for discharging the liquid toward the object and a standby position farther from the object in the third direction than the discharge position, wherein the contact detection unit is attached to cover the liquid ejection port with respect to the liquid ejection unit in a state where the liquid ejection unit is in the standby position, wherein the control means, after the position detection means detects the position of the liquid ejection unit with respect to the object, calculates a movement locus when the liquid ejection unit ejects the liquid toward the object, and performs a first operation of moving the liquid ejection unit along the calculated movement locus before the liquid ejection unit ejects the liquid toward the object. The liquid ejection device is characterized by this.

2. The contact detection unit includes a first member attached to the liquid ejection unit and a second member attached to be relatively movable with respect to the first member, The liquid ejection device according to claim 1, wherein the collision in the first direction with respect to the object is detected by the relative movement.

3. The liquid ejection device according to claim 1 or 2, wherein the position detection means includes detection means for detecting contact in the third direction.

4. The position detection means detects the position of the liquid ejection unit with respect to the object by the contact detection unit contacting the object in the third direction, The liquid ejection device according to any one of claims 1 to 3, wherein the control means calculates the movement locus based on the result of the detection.

5. The liquid ejection device according to any one of claims 1 to 4, wherein when an obstacle is detected on the object during the first operation, the detection of the obstacle is notified.

6. The liquid ejection device according to any one of claims 1 to 5, characterized in that when no obstacle is detected on the object during the first operation, a second operation of ejecting liquid onto the object is enabled.

7. The liquid ejection device according to claim 6, characterized in that in the first operation, the liquid ejection unit moves at the same speed as in the second operation.

8. The liquid ejection device according to claim 5 or 6, characterized in that the position detection means and the obstacle detection means for detecting an obstacle are detachably provided on the liquid ejection unit.

9. Comprising obstacle detection means for detecting an obstacle, The liquid ejection device according to any one of claims 5 to 7, characterized in that the position detection means and the obstacle detection means are provided integrally.

10. A liquid ejection method of a liquid ejection device including a liquid ejection port for ejecting liquid toward an object, and being movable in at least one of a first direction and a second direction intersecting the first direction, and in a third direction intersecting the first direction and the second direction and parallel to the direction of ejecting the liquid from the liquid ejection port toward the object, and including a liquid ejection unit movable between a liquid ejection position for ejecting the liquid toward the object and a standby position farther from the object in the third direction than the liquid ejection position, the method comprising: A position detection step of a position detection means of a contact detection unit mounted to cover the liquid ejection port with respect to the liquid ejection unit in a state of being in the standby position, for detecting a position of the liquid ejection unit with respect to the object; A movement trajectory calculation step of calculating a movement trajectory when the liquid ejection unit ejects liquid onto the object after detecting the position of the liquid ejection unit with respect to the object in the position detection step; A first step of moving the liquid ejection unit along the calculated movement trajectory before the liquid ejection unit ejects liquid onto the object and performing the method.

11. The liquid ejection method according to claim 10, characterized in that when no obstacle is detected on the object during the first step, a second step of ejecting liquid onto the object is enabled. A liquid ejection device comprising a liquid ejection port for ejecting a liquid toward an object, and a liquid ejection unit movable in at least one of a first direction and a second direction intersecting the first direction, and in a third direction intersecting the first direction and the second direction and parallel to the direction in which the liquid is ejected from the liquid ejection port toward the object, comprising a contact detection unit having position detection means for detecting the position of the liquid ejection unit with respect to the object, and control means for moving the liquid ejection unit along a predetermined movement locus based on input information, wherein the liquid ejection unit is movable between a discharge position for discharging the liquid toward the object and a standby position farther from the object in the third direction than the discharge position, wherein the contact detection unit is mounted so as to cover the liquid ejection port with respect to the liquid ejection unit in a state of being in the standby position, wherein the control means performs a first operation of moving the liquid ejection unit along the predetermined movement locus before the liquid ejection unit discharges the liquid toward the object along the predetermined movement locus. A liquid ejection device characterized by this.

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