LIQUID DISCHARGE UNIT AND LIQUID DISCHARGE APPARATUS

Abstract

To provide a liquid discharge unit which can supply a detergent to a liquid discharge surface which is provided in a manner that the liquid discharge surface can face a surface intersecting with a horizontal surface.SOLUTION: A liquid discharge unit discharges a liquid to an object having a surface intersecting with a horizontal surface and has: a liquid discharge surface which can face a surface intersecting with the horizontal surface; a cleaning device which cleans the liquid discharge surface; and driving means which moves the cleaning device relative to the liquid discharge surface. The cleaning device has: a contact member which is provided in a manner that the contact member can contact the liquid discharge surface; and a detergent supply device which supplies a detergent from the surface side of the contact member.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a liquid ejection unit and a liquid ejection device. [Background technology]

[0002] Patent Document 1 discloses a cleaning device for an ink discharge section comprising a first blade member for scraping off ink from the surface of the ink discharge section, a cleaning liquid roller for cleaning the surface of the ink discharge section with a water-soluble organic solvent, a water roller for cleaning the surface of the ink discharge section that has been cleaned with the water-soluble organic solvent with water, a second blade member for scraping off liquid from the surface of the ink discharge section that has been cleaned by the water roller, and a casing that supports the first blade member, the cleaning liquid roller, the water roller and the second blade member, wherein the casing is movable along the longitudinal direction of the surface of the ink discharge section, and the first blade member, the cleaning liquid roller, the water roller and the second blade member are arranged to come into contact with the surface of the ink discharge section in that order as the casing moves. Summary of the Invention [Problem to be solved by the invention]

[0003] An object of the present invention is to provide a liquid ejection unit capable of supplying a cleaning agent to a liquid ejection surface that is provided so as to be able to face a surface that intersects with a horizontal surface. [Means for solving the problem]

[0004] The present invention is a liquid ejection unit that ejects liquid toward an object having a surface that intersects with a horizontal plane, the liquid ejection unit having a liquid ejection surface that can face the surface that intersects with the horizontal plane, a cleaning device that cleans the liquid ejection surface, and a driving means that moves the cleaning device relatively to the liquid ejection surface, the cleaning device having a contact member that is provided so as to be able to come into contact with the liquid ejection surface, and a detergent supplying device that supplies detergent from the surface side of the contact member. a droplet receiving portion for receiving the liquid ejected from a liquid ejection port provided on the liquid ejection surface; Have The cleaning agent supplying device supplies the cleaning agent to the droplet receiving portion. The present invention is characterized by the above. Effect of the Invention

[0005] According to the present invention, it is possible to provide a liquid ejection unit capable of supplying a cleaning agent to a liquid ejection surface that is provided so as to be able to face a surface that intersects with a horizontal surface. [Brief description of the drawings]

[0006] [Figure 1] 1 is an overall perspective view of a liquid ejection device according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 4 is an overall perspective view of the carriage (at a liquid ejection position). [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 4 is an explanatory diagram of supply of a detergent to a detergent supply roller. [Figure 7] FIG. 4 is a block diagram of a portion relating to cleaning control. [Figure 8] FIG. 4 is a flow diagram showing an example of a printing process. [Figure 9] FIG. 4 is a flow diagram showing an example of a cleaning process. [Figure 10] FIG. 4 is a flow chart showing an example of a foreign matter removing process. [Figure 11] FIG. 4 is a flow diagram showing an example of a blank discharge process. [Figure 12] FIG. 4 is an explanatory diagram of the positional relationship of each member in a printing process. [Figure 13] FIG. 4 is an explanatory diagram of the positional relationship of each member in a cleaning process. [Figure 14] FIG. [Figure 15] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0008] FIG. 1 is an overall perspective view of a printing apparatus shown as an example of a liquid ejection apparatus of the present invention.

[0009] The printing device 1000 is installed facing a drawing target 100, which is an example of an object. The printing device 1000 includes an X-axis rail 101, a Y-axis rail 102 that intersects with the X-axis rail 101, and a Z-axis rail 103 that intersects with the X-axis rail 101 and the Y-axis rail 102.

[0010] The Y-axis rail 102 holds the X-axis rail 101 so that the X-axis rail 101 can move in the Y direction (positive and negative sides). The X-axis rail 101 also holds the Z-axis rail 103 so that the Z-axis rail 103 can move in the X direction (positive and negative sides). The Z-axis rail 103 then holds the carriage 1 so that the carriage 1 can move in the Z direction (positive and negative sides). Here, the carriage 1 is an example of a liquid ejection unit.

[0011] The printing device 1000 includes a first Z-direction drive unit 92 that moves the carriage 1 in the Z direction along the Z-axis rail 103, and an X-direction drive unit 72 that moves the Z-axis rail 103 in the X direction along the X-axis rail 101. The printing device 1000 also includes a Y-direction drive unit 82 that moves the X-axis rail 101 in the Y direction along the Y-axis rail 102. The printing device 1000 also includes a second Z-direction drive unit 93 that moves the head holder 70 in the Z direction relative to the carriage 1. Here, the head holder 70 is an example of a holder.

[0012] The printing device 1000 configured as described above ejects ink, which is an example of liquid, from a head provided on the head holder 70 while moving the carriage 1 in the X, Y, and Z directions, to perform drawing on the drawing target 100. Note that the movement of the carriage 1 and head holder 70 in the Z direction does not necessarily mean that it is parallel to the Z direction, and may be an oblique movement as long as it includes at least a component in the Z direction.

[0013] 1, the surface shape of the drawing object 100 is a flat surface, but the surface shape of the drawing object 100 may be a nearly vertical surface, a surface with a large radius of curvature, or a surface with some unevenness, such as the body of a car or truck, or the body of an airplane. In other words, any drawing object having a surface that intersects with the horizontal plane (XZ plane) is a target.

[0014] For printing devices that print on items that will ultimately be exposed to the outside air, such as signs, exterior walls of buildings, and vehicle bodies and aircraft bodies, the quick drying and strength of the printed surface is required. For this reason, the ink used for printing is, for example, an ink made by mixing a pigment with a volatile solvent such as thinner or acetone, or a highly viscous ink.

[0015] Next, the configuration of the carriage 1 will be described.

[0016] FIG. 2 is an overall perspective view of a carriage in a printing device shown as an example, showing a state in which the carriage is in a standby position on the Z axis.

[0017] The carriage 1, which is an example of a liquid ejection unit, is equipped with a head holder 70, which is an example of a holder. The carriage 1 is movable in the Z direction along a Z-axis rail 103 by power from a first Z-direction drive unit 92. The head holder 70 is movable in the Z direction relative to the carriage 1 by power from a second Z-direction drive unit 93 shown in FIG.

[0018] The head holder 70 holds a head, which is an example of a liquid ejection body, and here, six heads 300a to 300f are arranged in a layered manner on the head holder 70. In the following description, when these heads are collectively referred to, they will be referred to as head 300.

[0019] Each of the heads 300a to 300f includes a liquid ejection surface (nozzle surface) 302a having a plurality of liquid ejection ports (nozzles) 302. The type and number of ink colors used by the heads 300a to 300f may be different for each head, or may all be the same color. For example, if the liquid ejection device exemplified as the printing device 1000 is a coating device that uses a single color, the inks used by the heads 300a to 300f may be the same color. The number of heads constituting the head 300 is not limited to six. It may be more than six, or may be less than six.

[0020] As shown in the figure, the heads 300 are fixed to the head holder 70 so that the nozzle surface 302a of each head intersects with a horizontal plane (XZ plane) and the arrangement direction of the multiple nozzles 302 is inclined with respect to the X-axis. This causes the nozzles 302 to eject ink in a direction intersecting the direction of gravity (Z direction).

[0021] The carriage 1 also includes a cleaning device 4 that cleans the head 300. The carriage 1 supports a frame 2 that is provided so as to surround the periphery of the head holder 70. The frame 2 includes a shaft member 3 that extends in the X direction, and the cleaning device 4 is attached to the shaft member 3 so as to be movable along the shaft member 3.

[0022] Although not shown, the frame 2 includes a drive motor for moving the cleaning device 4 along the shaft member 3, a position sensor for detecting the position of the cleaning device 4 in the X direction (standby position, return position), and the like. As a result, the drive motor transmits power to the power transmission belt 5, and the cleaning device 4 connected to the power transmission belt 5 moves along the shaft member 3 in the positive X direction.

[0023] Then, the cleaning device 4 cleans the nozzle surface 302a and the nozzles 302 of the head 300. When the cleaning device 4 moves further in the positive X direction and reaches the turning back position, the movement direction of the cleaning device 4 switches to the negative X direction, and the cleaning device 4 returns to the standby position. Here, the drive motor, shaft member 3, power transmission belt 5, etc. are an example of a drive means that moves the cleaning device 4 relatively to the nozzle surface 302a.

[0024] FIG. 3 is an overall perspective view of a carriage in a printing device shown as an example, showing a state in which the carriage and head are in an ink ejection position on the Z axis.

[0025] The difference from FIG. 2 is that the carriage 1 and head holder 70 have been moved toward the drawing target 100 (positive side in the Z direction). Like the carriage 1, the head holder 70 also moves in the Z direction between the ink ejection position (FIG. 3) and the standby position (FIG. 2). Note that the Z direction position of the carriage 1 when ejecting ink is not always constant. The Z direction position of the carriage 1 when ejecting ink varies in accordance with the surface shape of the drawing target 100.

[0026] FIG. 4 is an explanatory diagram showing the configuration of the cleaning device, and shows the back side of the cleaning device 4 shown in FIGS.

[0027] As described above, in the case of ink in which a volatile solvent such as thinner or acetone is mixed into a highly viscous ink solvent, the ink solvent adheres due to the heat of vaporization generated when the volatile components of the thinner, acetone, etc. evaporate. In addition, components such as thinner and acetone evaporate quickly and evaporate immediately after the ink is ejected, so the ink solvent is likely to adhere to the nozzle 302 and the nozzle surface 302a. Furthermore, since the ink is highly viscous, once the ink adheres, it cannot be completely removed by simply rubbing it with a cleaning member such as a blade.

[0028] Therefore, in the present invention, the cleaning device 4 is provided with a cleaning agent supplier 41, a cleaning agent supply roller 42, a cleaning blade 43 and an empty discharge receiving surface 44, making it possible to remove ink that has adhered to the nozzles 302 and the nozzle surface 302a.

[0029] The cleaning device 4 moves back and forth between the positive side and the negative side in the X direction relative to the nozzle surface 302a of the head 300 when the carriage 1 is in a standby position on the Z axis (see FIG. 2).

[0030] The cleaning agent supplying device 41 has a cleaning agent supplying pipe 411 provided along the axial direction of the cleaning agent supplying roller 42. The cleaning agent supplying pipe 411 has a plurality of cleaning agent supplying ports 412 along the axial direction of the cleaning agent supplying roller 42, and supplies an organic solvent, which is an example of a cleaning agent, to each supply port described below. The first cleaning agent supplying port 412 is located close to the outer circumferential surface of the cleaning agent supplying roller 42, and sprays the organic solvent toward the outer circumferential surface of the cleaning agent supplying roller 42. Here, the cleaning agent supplying device 41 is an example of a cleaning agent supplying device.

[0031] At least the outer layer of the cleaning agent supply roller 42 is made of a sponge or the like that has high absorbency for organic solvents, and the cleaning agent supply roller 42 is configured so that the organic solvent can easily soak into the cleaning agent supply roller 42. When the cleaning agent supply roller 42 containing the organic solvent comes into contact with the nozzle surface 302a of the head 300, the organic solvent dissolves the residual ink that has adhered to the nozzle surface 302.

[0032] Furthermore, the cleaning agent supply roller 42 is driven to rotate in the direction of arrow A (counterclockwise) during cleaning. Therefore, when the cleaning device 4 is moved in the positive X direction relative to the nozzle surface 302a, the cleaning agent supply roller 42 comes into contact with the nozzle surface 302a while moving in the opposite direction (negative X direction) to the movement direction of the cleaning device 4. This makes it possible to continuously supply organic solvent to the remaining ink on the nozzle surface 302a, thereby more effectively dissolving the remaining ink.

[0033] Here, the detergent supply roller 42 is an example of a contact member. The embodiment of the contact member is not limited to a roller. For example, the contact member may be in the form of an endless belt supported by a plurality of shafts. The detergent may be supplied from the detergent supply device 41 to the detergent supply roller 42 by dripping it from above the detergent supply roller 42.

[0034] As described above, the cleaning agent supplier 41 sprays the cleaning agent onto the cleaning agent supply roller 42. This allows the cleaning agent to be supplied directly to the outer circumferential surface of the cleaning agent supply roller 42, making it possible to efficiently clean the nozzle surface 302a using a small amount of cleaning agent.

[0035] The cleaning blade 43 comes into contact with the nozzle surface 302a and scrapes off foreign matter such as residual ink that has adhered to the nozzle surface 302a. That is, the cleaning blade 43 is provided at a position on the negative side in the X direction with respect to the cleaning agent supply roller 42, and scrapes off foreign matter whose adhesive strength has been reduced by the organic solvent.

[0036] Here, the cleaning blade 43 is an example of the contact member. Note that the embodiment of the contact member is not limited to the above-mentioned one-blade configuration. For example, the contact member may be configured with a plurality of blades.

[0037] The blank discharge receiving surface 44 is a member that faces the nozzle surface 302a when blank discharge of ink is performed in the head 300, and receives ink droplets discharged from the nozzles 302. The blank discharge receiving surface 44 is provided at a position on the positive side in the X direction with respect to the cleaning agent supply roller 42, and is used for the blank discharge process that is performed when the cleaning device 4 moves (returns) to the negative side in the X direction.

[0038] Further, a second cleaning agent supply port 413 is provided on the upper part of the blank discharge receiving surface 44. The second cleaning agent supply port 413 is connected to the cleaning agent supply pipe 411 of the cleaning agent supplier 41, and the ink droplets received by the blank discharge receiving surface 44 are washed away by the organic solvent supplied from the second cleaning agent supply port 413. Here, the blank discharge receiving surface 44 is an example of a droplet receiving portion.

[0039] As described above, in this embodiment, the carriage 1 ejects ink toward the drawing object 100 having a surface that intersects with a horizontal plane (XZ plane), and includes a nozzle surface 302a that can face the surface that intersects with the horizontal plane, a cleaning device 4 that cleans the nozzle surface 302a, and a driving means (shaft member 3, power transmission belt 5, etc.) that moves the cleaning device 4 relatively to the nozzle surface 302a, and the cleaning device 4 includes a cleaning agent supply roller 42 that is arranged so as to be able to come into contact with the nozzle surface 302a, and a cleaning agent supplyer 41 that supplies a cleaning agent (organic solvent) from the surface side of the cleaning agent supply roller 42.

[0040] This makes it possible to provide the carriage 1 capable of uniformly supplying the cleaning agent to the nozzle surface 302a that is provided so as to be able to face a surface that intersects with the horizontal plane (XZ plane).

[0041] As described above, the cleaning device 4 has the cleaning blade 43 that comes into contact with the nozzle surface 302a after the cleaning agent has been supplied, and removes foreign matter such as residual ink from the nozzle surface 302a.

[0042] This makes it possible to reliably remove foreign matter, the adhesion of which to the nozzle surface 302a has been reduced by the organic solvent supplied by the cleaning agent supply roller 42, from the nozzle surface 302a.

[0043] As described above, the cleaning device 4 also has the blank discharge receiving surface 44 for receiving ink discharged from the nozzles 302 provided on the nozzle surface 302a.

[0044] This allows the blank discharge receiving surface 44 to collect foreign matter within the nozzle 302 and refresh the nozzle 302.

[0045] As described above, the cleaning agent supplier 41 supplies cleaning agent to the blank discharge receiving surface 44 .

[0046] This makes it possible to wash away the ink droplets received by the blank discharge receiving surface 44, and prevents the accumulation of ink droplets on the blank discharge receiving surface 44.

[0047] FIG. 5 is a configuration explanatory diagram of the cleaning agent supplying device, in which FIG. 5(a) is a schematic configuration diagram of a main part of the cleaning agent supplying device, and FIG. 5(b) is a plan view showing an example of a first shutter.

[0048] The cleaning agent supply device 41 mainly includes a cleaning agent supply pipe 411, a first cleaning agent supply port 412, and a second cleaning agent supply port 413. The cleaning agent is taken in from an upper portion of the cleaning agent supply pipe 411, and a first shutter 414 and a second shutter 415 are provided on a cleaning agent supply path to each of the cleaning agent supply ports 412, 413.

[0049] The first shutter 414 opens when the cleaning agent is supplied to the cleaning agent supply roller 42, and closes when the cleaning agent is not supplied to the cleaning agent supply roller 42. The second shutter 415 opens when the cleaning agent is supplied to the idle discharge receiving surface 44, and closes when the cleaning agent is not supplied to the idle discharge receiving surface 44.

[0050] Also, the opening diameter of the first shutter 414 may be variable as shown in Fig. 5(b). That is, (i) in Fig. 5(b) is a state in which the first shutter 414 is closed, and the opening diameter of the first shutter 414 is controlled according to the ink ejection amount, the time during which ink is not ejected, the type of ink, and the environmental temperature and humidity. In (ii) in Fig. 5(b), the amount of cleaning agent supplied is small, and in (iii) in Fig. 5(b), the amount of cleaning agent supplied is large. Here, the first shutter 414 is an example of a shutter member.

[0051] As described above, the cleaning agent supplier 41 has the first shutter 414 on the supply path of the cleaning agent supply pipe 411 for varying the opening diameter (opening area) of the supply path.

[0052] This allows the nozzle face 302a to be efficiently cleaned with a minimum amount of cleaning agent.

[0053] Here, when the detergent supply roller 42 is vertically oriented as in this embodiment, i.e., when the roller rotation axis has a Y-direction (vertical direction) component, the detergent that has soaked into the detergent supply roller 42 flows in the direction of gravity. As a result, the upper side of the detergent supply roller 42 in the axial direction tends to dry out, making it difficult to uniformly soak the detergent in the axial direction of the detergent supply roller 42.

[0054] Therefore, the opening diameter of the cleaning agent supply port 412 is changed for each cleaning agent supply port to provide a difference in the amount of cleaning agent supplied. Specifically, a detachable cap member 416 is provided for the first cleaning agent supply port 412. There are multiple types of cap members 416 with different opening diameters.

[0055] A cap member 416 is attached in advance to the first cleaning agent supply port 412 so that the amount of cleaning agent supplied decreases from the upper cleaning agent supply port to the lower cleaning agent supply port.

[0056] FIG. 6 is an explanatory diagram of supply of the cleaning agent to the cleaning agent supply roller.

[0057] The opening diameter of the first cleaning agent supply port 412 is adjusted by the cap member 416 so that the amount of cleaning agent supplied from the first cleaning agent supply port 412 decreases from the upper cleaning agent supply port to the lower cleaning agent supply port. By providing such a cap member 416, it is possible to improve the uneven distribution of the cleaning agent in the axial direction of the cleaning agent supply roller 42, and the cleaning agent can be supplied to the cleaning agent supply roller 42 evenly and sufficiently.

[0058] The configuration for decreasing the amount of cleaning agent supplied from the upper cleaning agent supply port to the lower cleaning agent supply port is not limited to the above. For example, the cleaning agent supply roller may be installed with its axis tilted by 30 degrees, preferably 45 degrees or more, with respect to the cleaning agent supply device 41. This makes it possible to provide a difference in the amount of cleaning agent supplied, since the distance to the cleaning agent supply roller varies from the upper cleaning agent supply port to the lower cleaning agent supply port. Also, installing the cleaning agent supply roller at an angle is more effective because it prevents the cleaning agent supply roller from being continuously immersed in the cleaning agent.

[0059] As described above, the cleaning agent supplier 41 has a plurality of cleaning agent supply ports 412 in the direction of a surface intersecting the horizontal surface (XZ surface), and the supply amount of cleaning agent decreases from the upper cleaning agent supply port to the lower cleaning agent supply port.

[0060] This allows the detergent to be evenly supplied to the detergent supply roller 42 even when the roller 42 is vertically disposed.

[0061] FIG. 7 is a block diagram of a portion relating to cleaning control.

[0062] The printing apparatus 1000 includes an X-direction drive unit 72, a Y-direction drive unit 82, a first Z-direction drive unit 92, a second Z-direction drive unit 93, a cleaning device drive unit 94, a detergent supply roller drive unit 95, a shutter drive unit 96, a detergent supply unit 97, and the like.

[0063] The printing device 1000 also has a control unit 500, which includes a cleaning execution determination unit 504, a cleaning agent supply amount calculation unit 505, and a consumables status determination unit 506. The control unit 500 is further connected to a memory unit 501, a display unit 502, an operation panel 503, and the like.

[0064] The X-direction driving unit 72 drives the carriage 1 in the X direction (positive and negative sides) based on instructions from the control unit 500. The Y-direction driving unit 82 drives the carriage 1 in the Y direction (positive and negative sides) based on instructions from the control unit 500.

[0065] The first Z-direction driving unit 92 drives the carriage 1 in the Z direction (positive and negative sides) based on instructions from the control unit 500. The second Z-direction driving unit 93 drives the head holder 70 in the Z direction (positive and negative sides) relative to the carriage 1 based on instructions from the control unit 500.

[0066] The cleaning device drive unit 94 drives the cleaning device 4 in the X direction (positive side and negative side) and the Z direction (positive side and negative side) relative to the head 300 based on instructions from the control unit 500. The cleaning agent supply roller drive unit 95 drives the cleaning agent supply roller 42 to rotate based on instructions from the control unit 500.

[0067] Based on instructions from the control unit 500, the shutter driving unit 96 adjusts the opening diameter and opens and closes the first shutter 414 provided in the cleaning agent supplier 41, and opens and closes the second shutter 415. The cleaning agent supplier 97 starts and stops the supply of the cleaning agent to the cleaning agent supplier 41.

[0068] The control unit 500 includes a CPU that is responsible for the overall control of the printing device 1000, a ROM that stores programs for executing control of drawing operations and other fixed data on the CPU, etc. The control unit 500 includes a RAM that temporarily stores drawing data and other data to be drawn on the drawing target 100, and an I / F for transmitting and receiving data and signals used when receiving drawing data and other data from a host such as a PC.

[0069] The control unit 500 stores (stores) in the memory unit 501 and reads out information such as the amount of ink discharged from the nozzles 302 of the head 300, the time when ink is not discharged from the nozzles 302, the type of ink, and the environmental temperature and humidity.

[0070] The control unit 500 controls the X-direction driving unit 72, the Y-direction driving unit 82, the first Z-direction driving unit 92, and the second Z-direction driving unit 93 to move the carriage 1 and the head holder 70 along the surface shape of the drawing target 100. The control unit 500 also controls the ejection of ink from the head 300 provided on the head holder 70.

[0071] If an abnormality occurs in the carriage 1, the head holder 70, or the head 300, the control unit 500 notifies the user by displaying the abnormality on the display unit 502. The control unit 500 also receives instructions from the operation panel 503 and executes processing corresponding to the instructions.

[0072] The control unit 500 includes a cleaning execution determination unit 504, a cleaning agent supply amount calculation unit 505, and a consumables status determination unit 506. The control unit 500 receives instructions from the cleaning execution determination unit 504, and drives the cleaning device drive unit 94 and the cleaning agent supply roller drive unit 95.

[0073] The control unit 500 also receives instructions from a cleaning agent supply amount calculation unit 505 and drives the shutter drive unit 96 and the cleaning agent supply unit 97. Furthermore, the control unit 500 receives instructions from a consumables status determination unit 506 and displays on the display unit 502 information on the consumption status of ink and cleaning agent, and information on the replacement timing of the cleaning agent supply roller 42 and the cleaning blade 43, etc.

[0074] The storage unit 501 stores information regarding the ink ejection amount, the time during which ink is not ejected, the type of ink, and the environmental temperature and humidity, as well as coordinate information (three-dimensional (XYZ) coordinate information) indicating the surface shape of the drawing target 100, and the like.

[0075] When an abnormality occurs in the printing device 1000, the display unit 502 displays the details of the abnormality to notify the user. The operation panel 503 allows input of values ​​(coordinates) for specifying a drawing area for the drawing target 100, the moving speed of the carriage 1, and the distance between the head 300 and the drawing target 100. The operation panel 503 also allows designation of coordinate information to be used for drawing. The display unit 502 and the operation panel 503 may be operated on a single screen using a touch panel or the like.

[0076] The cleaning execution determination unit 504 determines whether cleaning of the head 300 is necessary based on information on the moving distance of the carriage 1. Note that the information on the moving distance of the carriage 1 can be obtained from, for example, the amount of rotation of the drive motor of the X-direction drive unit 72.

[0077] The detergent supply amount calculation unit 505 calculates the amount of detergent supply based on the ink ejection amount, the time when ink is not ejected, the type of ink, and information on the environmental temperature and humidity, etc., stored in the memory unit 501. The control unit 500 drives the shutter drive unit 96 and the detergent supply unit 97 based on the calculation result by the detergent supply amount calculation unit 505.

[0078] The consumables status determination unit 506 transmits information regarding the timing of replacement of various consumables based on the consumption status of ink and detergent and the wear status of the detergent supply roller 42 and cleaning blade 43 to the control unit 500 .

[0079] FIG. 8 is a flow chart showing an example of a drawing process of the printing device according to the present invention.

[0080] In the case of the printing device 1000 shown in FIG. 1, the carriage 1 located at the drawing start position is moved in the positive X direction, and one scan of drawing (printing) is performed on the drawing target 100 by this movement in the positive X direction (outward movement) (step S1).

[0081] If the surface shape of the object to be drawn 100 is not flat, the carriage 1 not only moves in the positive X-direction but also in the Z-direction based on three-dimensional coordinate information indicating the surface shape of the object to be drawn 100, and draws by following the surface shape of the object to be drawn 100.

[0082] When drawing for one scan on the forward path is completed, the head holder 70 moves from the liquid ejection position shown in FIG. 3 to the standby position shown in FIG.

[0083] The period during which the head holder 70 is in the standby position is also a cleaning possible period, and during this period the cleaning device 4 is driven to clean the head 300 (step S2).

[0084] Cleaning of the head 300 by the cleaning device 4 is completed before drawing begins by moving the carriage 1 in the negative X-direction. In the cleaning process of step S2, the cleaning device 4 moves over the nozzle surface 302a of the head 300, and removes foreign matter such as residual ink adhered to the nozzle surface 302a and performs idle ejection.

[0085] When the carriage 1 moves in the positive X direction and reaches the turn-back position, the carriage 1 moves one scan in the negative Y direction (line feed). After the line feed, the carriage 1 starts moving in the negative X direction, and by this movement in the negative X direction (return path), a new drawing for one scan is performed on the drawing target 100 (step S3).

[0086] When drawing for one scan on the return path is completed, the head holder 70 moves from the liquid ejection position to the standby position, as in step S2, and drives the cleaning device 4 during the cleaning period to clean the head 300 (step S4). Cleaning of the head 300 by the cleaning device 4 is completed before the carriage 1 starts moving in the positive X-direction.

[0087] The control unit 500 of the printing device 1000 repeats steps S1 to S4 until drawing is completed, and when the control unit 500 determines that drawing is completed, the drawing process is completed (step S5).

[0088] FIG. 9 is a flow diagram showing an example of the cleaning process, and shows details of the cleaning process carried out in steps S2 and S4 in FIG.

[0089] When the printing device 1000 completes drawing for one scan on the outward path, the head holder 70 moves from the liquid ejection position shown in Fig. 3 to the standby position shown in Fig. 2. The cleaning device 4 cleans the head 300 while the head holder 70 is in the standby position (cleanable period).

[0090] In the cleaning process, first, it is determined whether cleaning of the head 300 is necessary (step S11). This determination is made by the cleaning execution determination unit 504, which determines whether cleaning is necessary based on information such as the movement distance of the carriage 1. If cleaning is not necessary (No), the process ends without cleaning. If cleaning is necessary (Yes), the supply amount of detergent (organic solvent) necessary for cleaning is calculated (step S12).

[0091] The amount of detergent supply is calculated by a detergent supply amount calculation unit 505. The detergent supply amount calculation unit 505 calculates the amount of detergent supply based on the ink ejection amount, the time when ink is not ejected, the type of ink, and information on the environmental temperature and humidity stored in the memory unit 501. The control unit 500 drives the shutter drive unit 96 and the detergent supply unit 97 based on the calculation result.

[0092] After the calculation of the supply amount of the cleaning agent is completed, the cleaning device 4 starts to move in the positive X-direction (forward path) relative to the nozzle surface 302a (step S13). While the cleaning device 4 is moving in the positive X-direction, the cleaning device 4 removes foreign matter using the cleaning agent supply roller 42 and the cleaning blade 43 (step S14).

[0093] When the cleaning agent supply roller 42 and the cleaning blade 43 pass over the nozzle surface 302a and reach the turning back position, the cleaning device 4 starts moving in the negative X-direction (returning direction) (step S15).

[0094] During the period when the cleaning device 4 is moving to the negative side in the X direction, the nozzle 302 performs idle discharge toward the idle discharge receiving surface 44 of the cleaning device 4 (step S16). The cleaning process ends with the above steps.

[0095] FIG. 10 is a flow diagram showing an example of the foreign matter removal process, and shows details of the foreign matter removal process carried out in step S14 of FIG.

[0096] When the foreign matter removal process begins, the cleaning agent supply roller 42 starts to rotate (step S21). At the same time, the first shutter 414 of the cleaning agent supply device 41 opens, and the organic solvent starts to be sprayed from the first cleaning agent supply port 412 (step S22). This causes the cleaning agent supply roller 42 to hold the organic solvent.

[0097] In this state, the cleaning device 4 is moved in the X direction positive side (forward path) relative to the nozzle surface 302a, and foreign matter is removed by the cleaning agent supply roller 42 and the cleaning blade 43 (step S23). When the cleaning agent supply roller 42 and the cleaning blade 43 pass over the nozzle surface 302a and reach the turning back position, the rotation of the cleaning agent supply roller 42 is stopped (step S24).

[0098] Also, first shutter 414 of cleaning agent supplier 41 closes to stop the spray of the organic solvent from first cleaning agent supply port 412 (step S25). Next, an increment process is performed on the count value of the number of cleaning operations (step S26).

[0099] Next, based on the information on the number of cleaning operations performed, etc., it is determined whether or not consumables such as the detergent supply roller 42 and the cleaning blade need to be replaced (step S27). This determination is made by the consumables status determination unit 506.

[0100] If the consumables status determination unit 506 determines that the consumables do not need to be replaced (No), the foreign matter removal process ends. If the consumables status determination unit 506 determines that the consumables need to be replaced (Yes), the consumables status determination unit 506 displays an alert on the display unit 502 via the control unit 500 (step S28). This notifies the user that the consumables need to be replaced.

[0101] In this embodiment, the cleaning agent supply roller 42 and the cleaning blade 43 are not used in the idle discharge step that follows the foreign matter removal step. Therefore, in step S28, an alert is simply displayed, allowing the series of cleaning steps to continue. The foreign matter removal step is completed with the above steps.

[0102] FIG. 11 is a flow diagram showing an example of the blank discharge step, and shows the details of the blank discharge step carried out in step S16 of FIG.

[0103] When the dummy discharge step starts, the second shutter 415 of the cleaning agent supplier 41 opens, and the supply of the organic solvent from the second cleaning agent supply port 413 starts (step S31). This causes the organic solvent to flow from the upper part to the lower part of the dummy discharge receiving surface 44.

[0104] In this state, the cleaning device 4 is moved in the negative X-direction (returning path) relative to the nozzle surface 302a, and ink is discharged sequentially from the nozzles 302 facing the blank discharge receiving surface 44 (step S32). As a result, foreign matter and the like that has become clogged in the nozzles 302 adheres to the blank discharge receiving surface 44. This operation is repeated until the cleaning device 4 reaches the end point of the return path (step S33).

[0105] When the blank discharge receiving surface 44 passes over the nozzle surface 302a, the ink discharge is stopped (step S34), the second shutter 415 of the cleaner dispenser 41 is closed, and the supply of cleaner from the second cleaner supply port 413 is stopped (step S35). With these steps, the blank discharge process is completed.

[0106] FIG. 12 is an explanatory diagram of the positional relationship of each member in the printing process.

[0107] When drawing (printing) on ​​the drawing target 100, the Z-axis rail 103 carrying the carriage 1 moves in the positive X-direction along the X-axis rail 101. The head 300 ejects ink toward the drawing target 100 while moving in the positive X-direction, printing one scan's worth of an image on the drawing target 100. During the illustrated printable period, the head holder 70 holding the head 300 is in a position (liquid ejection position) that protrudes from the carriage 1 in the positive Z-direction (toward the drawing target 100).

[0108] In addition, if the surface shape of the drawing object 100 is curved or has an uneven surface shape, the entire carriage 1 moves back and forth along the Z-axis rail 103, drawing while following the surface shape of the drawing object 100.

[0109] When drawing for one scan on the forward path is completed, the head holder 70 moves to the negative side in the Z direction and temporarily moves to the standby position as shown on the right side of the figure. While the head holder 70 is in the standby position (cleanable period), the cleaning device 4 moves back and forth in the X direction over the nozzle surface 302a of the head 300.

[0110] During the reciprocating movement of the cleaning device 4, foreign matter removal is performed using a cleaning agent supply roller 42 and a cleaning blade 43 provided on the cleaning device 4 on the outbound path, and idle discharge is performed using an idle discharge receiving surface 44 provided on the cleaning device 4 on the return path.

[0111] When cleaning is complete, the carriage 1 moves one scan (line feed) in the negative (or positive) Y direction, and then the head holder 70, which was in the standby position, moves again to the liquid ejection position. Thereafter, the Z-axis rail 103 carrying the carriage 1 moves in the negative X direction along the X-axis rail 101. As the head 300 moves in the negative X direction, it ejects ink toward the drawing object 100, and draws a new image for one scan on the drawing object 100.

[0112] When drawing for one scan on the return path is completed, the head holder 70 moves to the negative Z direction and moves to the standby position as shown on the left side of the figure. After that, the cleaning device 4 performs head cleaning in the same manner as described above. The above operations are repeated until drawing is completed.

[0113] FIG. 13 is an explanatory diagram of the positional relationship of each member in the cleaning process.

[0114] During cleaning, the cleaning device 4 in the standby position moves toward the positive side in the X direction, and the cleaning device 4 starts moving in the forward direction. First, the detergent supply roller 42 of the cleaning device 4 comes into contact with the nozzle surface 302a of the head 300. The idle discharge receiving surface 44 is shifted toward the positive side in the Z direction from the contact surface between the detergent supply roller 42 and the nozzle surface 302a, and the idle discharge receiving surface 44 passes directly over the nozzle surface 302a during the forward movement.

[0115] The cleaning agent supply roller 42 that has come into contact with the nozzle surface 302a moves over the nozzle surface 302a in the positive direction in the X direction while supplying an organic solvent to the nozzle surface 302a. Following the cleaning agent supply roller 42, the cleaning blade 43 of the cleaning device 4 comes into contact with the nozzle surface 302a, and the cleaning blade 43 scrapes off and removes foreign matter such as residual ink that has adhered to the nozzle surface 302a.

[0116] When the cleaning agent supply roller 42 and the cleaning blade 43 pass over the nozzle surface 302a and reach the turning back position (position indicated by the broken line in the figure), the cleaning device 4 starts moving in the negative X-direction (returning path). On the return path, the nozzles 302 of the head 300 perform idle discharge toward the idle discharge receiving surface 44 of the cleaning device 4.

[0117] In addition, in the case of idling, if the distance between the nozzle surface 302a and the idling receiving surface 44 is too close, the ink is likely to bounce back and splash. In that case, the cleaning device 4 may be moved to the positive side in the Z direction or the carriage 1 may be moved to the negative side in the Z direction before starting the return movement, and the positions may be corrected to suppress the ink splashing.

[0118] FIG. 14 is an explanatory diagram of foreign matter removal, in which FIG. 14(a) shows the state before the foreign matter is removed, FIG. 14(b) shows the state during the foreign matter removal, and FIG. 14(c) shows the state after the foreign matter is removed.

[0119] As shown in FIG. 14(a), ink (residual ink) M1 ejected from the nozzles 302 during printing is adhered to the nozzle surface 302a of the head 300 after printing.

[0120] As shown in FIG. 14(b), by supplying a sufficient amount of cleaning agent to the residual ink M1 by the cleaning agent supply roller 42, the adhesive force of the residual ink M1 to the nozzle surface 302a decreases, and the residual ink M1 becomes dissolved residual ink M2.

[0121] Thereafter, the dissolved residual ink M2 is scraped off by the cleaning blade 43, and foreign matter including the residual ink is removed from the nozzle surface 302a, as shown in FIG. 14(c).

[0122] FIG. 15 is an explanatory diagram of the idle discharge, in which FIG. 15(a) shows the state before the start of the idle discharge, FIG. 15(b) shows the state when the supply of the cleaning agent starts, and FIG. 15(c) shows the state during the idle discharge.

[0123] As described above, the idle discharge is performed during the return movement of the cleaning device 4. While the cleaning device 4 is moving in the forward direction, as shown in Fig. 15(a), the organic solvent is not supplied to the idle discharge receiving surface 44.

[0124] 15(b), when the cleaning device 4 starts to move in the return direction, the supply of the organic solvent S1 starts from the second cleaning agent supply port 413. The blank discharge receiving surface 44 moves over the nozzle surface 302a of the head 300 facing the blank discharge receiving surface 44 while receiving the supply of the organic solvent S1.

[0125] Each nozzle 302 of the head 300 performs blank discharge toward the blank discharge receiving surface 44 at a timing when the nozzles 302 face the blank discharge receiving surface 44. The organic solvent flowing on the blank discharge receiving surface 44 causes the ink droplets M3 received by the blank discharge receiving surface 44 to flow downward, thereby cleaning the blank discharge receiving surface 44.

[0126] The organic solvent that has flowed down the empty discharge receiving surface 44 flows to a recovery section (not shown) provided below the empty discharge receiving surface 44, and this recovery section discharges the organic solvent to the outside.

[0127] In the present invention, the liquid may be a solution, suspension, emulsion, etc. containing a solvent such as water or an organic solvent, a colorant such as a dye or a pigment, a functionality-imparting material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, amino acids, proteins, or calcium, an edible material such as a natural dye, or the like.

[0128] These can be used, for example, in ink-jet inks, coating materials, surface treatment liquids, components of electronic elements and light-emitting elements, liquids for forming electronic circuit resist patterns, and material liquids for three-dimensional modeling.

[0129] The liquid ejection device according to the present invention is not limited to the above-mentioned printing device. For example, the liquid ejection unit according to the present invention may be attached to the tip of a robot arm of a multi-joint robot that can move freely like a human arm by using multiple joints. The liquid ejection unit according to the present invention may be mounted on an unmanned aerial vehicle such as a drone or a robot that can climb walls, to form an unmanned aerial vehicle capable of painting or a climbing robot capable of painting.

[0130] The above description is merely an example, and the present invention provides unique effects for each of the following aspects.

[0131] (Aspect 1) Aspect 1 is a liquid ejection unit (e.g., carriage 1) that ejects liquid (e.g., ink) toward an object (e.g., drawing object 100) having a surface that intersects with a horizontal plane (e.g., XZ plane), and is characterized in that it has a liquid ejection surface (e.g., nozzle surface 302a) that can face the surface that intersects with the horizontal plane, a cleaning device (e.g., cleaning device 4) that cleans the liquid ejection surface, and a drive means (e.g., shaft member 3, power transmission belt 5, cleaning device drive unit 94, etc.) that moves the cleaning device relative to the liquid ejection surface, and the cleaning device has a contact member (e.g., detergent supply roller 42) that is arranged to be able to come into contact with the liquid ejection surface, and a detergent supply device (e.g., detergent supply device 41) that supplies a detergent (e.g., an organic solvent) from the surface side of the contact member.

[0132] According to the first aspect, it is possible to provide a liquid ejection unit capable of evenly supplying a cleaning agent to a liquid ejection surface that is provided so as to be able to face a surface that intersects with a horizontal surface.

[0133] (Aspect 2) Aspect 2 is characterized in that, in aspect 1, the cleaning device (e.g., cleaning device 4) has a contact member (e.g., cleaning blade 43) that contacts the liquid ejection surface (e.g., nozzle surface 302a) after the cleaning agent (e.g., organic solvent) has been supplied, and removes foreign matter (e.g., residual ink M2) from the liquid ejection surface.

[0134] According to the second aspect, foreign matter whose adhesive force to the liquid ejection surface has decreased can be reliably removed from the liquid ejection surface by the cleaning agent supplied by the contact member.

[0135] (Aspect 3) Aspect 3 is characterized in that, in aspect 1 or aspect 2, the cleaning device (e.g., cleaning device 4) has a droplet receiving portion (e.g., idling receiving surface 44) for receiving the liquid (e.g., ink) ejected from a liquid ejection port (e.g., nozzle 302) provided on the liquid ejection surface (e.g., nozzle surface 302a).

[0136] According to the third aspect, the droplet receiving portion can collect foreign matter inside the liquid ejection orifice, thereby refreshing the liquid ejection orifice.

[0137] (Aspect 4) Aspect 4 is characterized in that in any one of Aspects 1 to 3, the cleaning agent supplying device (e.g., cleaning agent supplying device 41) supplies the cleaning agent (e.g., organic solvent) to the droplet receiving portion (e.g., blank discharge receiving surface 44).

[0138] According to the fourth aspect, it becomes possible to wash away the liquid received in the droplet receiving portion, and it is possible to prevent the accumulation of liquid in the droplet receiving portion.

[0139] (Aspect 5) Aspect 5 is characterized in that in any one of Aspects 1 to 4, the cleaning agent supplying device (e.g., cleaning agent supply unit 41) has a shutter member (e.g., first shutter 414) on a supply path (e.g., cleaning agent supply pipe 411) of the cleaning agent (e.g., organic solvent) that varies the opening area of ​​the supply path (e.g., the opening diameter of cleaning agent supply pipe 411).

[0140] According to the fifth aspect, the liquid ejection surface can be efficiently cleaned with a minimum amount of cleaning agent.

[0141] (Aspect 6) A sixth aspect is any one of the first to fifth aspects, characterized in that the cleaning agent supplying device (e.g., cleaning agent supplying device 41) has a plurality of cleaning agent supplying ports (e.g., first cleaning agent supplying port 412) in a direction of a plane intersecting with the horizontal plane (e.g., XZ plane), and the supply amount of the cleaning agent (e.g., organic solvent) decreases from an upper cleaning agent supplying port to a lower cleaning agent supplying port.

[0142] According to the sixth aspect, the cleaning agent can be evenly supplied to the contact member even when the contact member is placed vertically.

[0143] (Aspect 7) A seventh aspect is the same as the first aspect, in which the detergent supplying device (eg, detergent supply unit 41) sprays the detergent onto the contact member (eg, detergent supply roller 42).

[0144] According to the seventh aspect, the cleaning agent is supplied directly to the outer circumferential surface of the contact member, and the liquid ejection surface can be efficiently cleaned using a small amount of cleaning agent. [Explanation of symbols]

[0145] 1 Carriage (liquid ejection unit) 70 Head holder 300 Head 302 Nozzle (liquid outlet) 302a Nozzle surface (liquid ejection surface) 4 Cleaning device 41 Detergent supply device (detergent supply device) 42 Detergent supply roller (contact member) 43 Cleaning blade (contact member) 44 Empty discharge receiving surface (droplet receiving part) 411 Cleaning agent supply pipe (supply line) 412 First cleaning agent supply port 413 Second cleaning agent supply port 414 First Shutter 415 Second Shutter [Prior art documents] [Patent documents]

[0146] [Patent Document 1] JP 2012-153152 A

Claims

1. A liquid ejection unit that ejects liquid toward a target having a surface that intersects with a horizontal plane, a liquid ejection surface that can face a surface that intersects with the horizontal surface; a cleaning device for cleaning the liquid ejection surface; a driving means for moving the cleaning device relative to the liquid ejection surface; With The cleaning device includes: a contact member provided so as to be able to come into contact with the liquid ejection surface; a cleaning agent supplying device for supplying a cleaning agent from a surface side of the contact member; a droplet receiving portion for receiving the liquid ejected from a liquid ejection port provided on the liquid ejection surface; having The liquid ejection unit is characterized in that the cleaning agent supplying device supplies the cleaning agent to the droplet receiving portion.

2. A liquid ejection unit that ejects liquid toward an object having a surface that intersects with a horizontal plane, a liquid ejection surface that can face a surface that intersects with the horizontal surface; a cleaning device for cleaning the liquid ejection surface; a driving means for moving the cleaning device relative to the liquid ejection surface; With The cleaning device includes: a contact member provided so as to be able to come into contact with the liquid ejection surface; a detergent supplying device for supplying a detergent from the surface side of the contact member; having The cleaning agent supply device is provided with a plurality of cleaning agent supply ports in the direction of a surface intersecting the horizontal plane, and the amount of cleaning agent supplied decreases from the upper cleaning agent supply port to the lower cleaning agent supply port.

3. The liquid ejection unit according to claim 1 or 2, characterized in that the cleaning device has an abutment member that abuts against the liquid ejection surface after the cleaning agent has been supplied and removes foreign matter from the liquid ejection surface.

4. The liquid ejection unit described in claim 2, characterized in that the cleaning device has a droplet receiving portion for receiving the liquid ejected from a liquid ejection port provided on the liquid ejection surface.

5. 5. The liquid ejection unit according to claim 1, wherein the cleaning agent supplying device has a shutter member on a supply path of the cleaning agent, the shutter member making an opening area of ​​the supply path variable.

6. The liquid ejection unit described in claim 1, characterized in that the cleaning agent supplying device sprays the cleaning agent onto the contact member.

7. A liquid ejection unit that ejects liquid toward an object having a surface that intersects with a horizontal plane, a liquid ejection surface that can face a surface that intersects with the horizontal surface; a cleaning device for cleaning the liquid ejection surface; a driving means for moving the cleaning device relative to the liquid ejection surface; With The cleaning device includes: a contact member provided so as to be able to come into contact with the liquid ejection surface; a detergent supplying device for supplying a detergent from the surface side of the contact member; having The liquid ejection unit is characterized in that the detergent supplying device is provided with a plurality of detergent supplying ports in a direction of a plane intersecting the horizontal plane.

8. A liquid ejection device comprising a liquid ejection unit according to any one of claims 1 to 7.

9. A liquid ejection device as described in claim 8, characterized in that the amount of cleaning agent supplied is controlled depending on at least one of the amount of liquid ejected from the liquid ejection port provided on the liquid ejection surface, the time during which the liquid is not ejected from the liquid ejection port, the type of liquid, and the environmental temperature and humidity.

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