JP7243396B2 - Device for ejecting liquid - Google Patents

Description

The present invention relates to an apparatus for ejecting liquid.

2. Description of the Related Art Devices that eject liquid include, for example, those that eject liquid onto the surface of cylinders, aircraft, vehicles, and the like to print.

Conventionally, for example, a head array, a linear rail for reciprocating linear movement of the head array, an articulated robot equipped with a robot arm that appropriately moves the linear rail to a predetermined position and holds it at that position, and a controller that provides positional information to the robot arm controller and drives and controls predetermined inkjet nozzles in the head array in conjunction with the positional information. It is known (Patent Document 1).

JP 2015-27636 A

By the way, in an apparatus that uses a head that ejects liquid, cleaning means (maintenance means) for maintaining and restoring the state of the nozzle surface (ejection surface) is provided on the side of the apparatus main body, and the head is cleaned at a predetermined timing. It moves to the position of the cleaning means.

Therefore, in an apparatus with a long scanning distance of the head, there is a problem that the down time associated with the cleaning operation becomes long and the printing speed becomes slow.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to enable cleaning of the nozzle surface when necessary.

In order to solve the above problems, the device for ejecting liquid according to the present invention includes:
a head having nozzles for ejecting liquid;
a wiping member for wiping the nozzle surface of the head;
a moving member that holds the wiping member and is movable between a position where the wiping member faces the nozzle surface and a position where the wiping member is retracted from the nozzle surface;
a housing that holds the head and movably supports the moving member;
a discharge unit comprising a cleaning liquid application means for discharging or dropping a cleaning liquid ;
and a reciprocating moving body on which the ejection unit is mounted.

According to the present invention, the nozzle surface can be cleaned when necessary.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side explanatory view of an apparatus for ejecting liquid according to a first embodiment of the present invention; It is also a front explanatory view. It is similarly a plane explanatory view. FIG. 3 is a block explanatory diagram similarly used for explaining a control unit; FIG. 10 is an explanatory diagram similarly used for explaining the relationship between the print range and the print data; FIG. 11 is an explanatory diagram for explaining an example of divided print areas when printing is performed over the entire periphery of the cylinder; FIG. 5 is a flow diagram for explaining control of printing operation by the same control unit; FIG. 10 is an explanatory diagram of a trajectory of the head for explaining the printing operation on the cylinder by the same apparatus; It is a perspective explanatory view of an example of the discharge unit in the same embodiment. It is also a side explanatory view. It is similarly a front explanatory view of a head part. FIG. 4 is an explanatory diagram for similarly describing a cleaning liquid supply system for the cleaning mechanism and a cleaning operation control system; FIG. 4 is a cross-sectional explanatory view of one nozzle portion for explaining an example of the head in the same embodiment; FIG. 4 is an explanatory diagram of an example of drive voltages used for explaining the operation of the head; FIG. 4 is an explanatory diagram of a liquid supply system for the same head; FIG. 5 is a flow diagram for explaining an example of cleaning processing by a control unit; FIG. 5 is a flow diagram for explaining an example of control of cleaning operation by a cleaning control unit; FIG. 11 is a perspective explanatory view for explaining a discharge unit according to a second embodiment of the present invention; FIG. 11 is a perspective explanatory view when printing an aircraft as a print target with a device for ejecting liquid according to a third embodiment of the present invention; It is a perspective explanatory view of the apparatus which discharges the same liquid. FIG. 11 is a perspective explanatory view of a device for ejecting liquid according to a fourth embodiment of the present invention; It is a perspective explanatory view of the drive part of the same apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. A first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. FIG. 1 is an explanatory side view of an apparatus for ejecting liquid according to the same embodiment, FIG. 2 is an explanatory front view of the same, and FIG. 3 is an explanatory plan view of the same.

A device 1 for ejecting liquid has a mounting table 11 for mounting a cylinder 2, which is a columnar member as an object to be printed, on a base 10, and the cylinder 2 mounted on the mounting table 11 is fixed and held from above. and a fixing means 12 for Further, on the base 10, an ejection unit 13 including a head 300, which is liquid ejection means for ejecting liquid onto the peripheral surface of the cylinder 2, and a carriage 14 on which the ejection unit 13 is mounted are provided.

The mounting table 11 is composed of a turntable installed rotatably with respect to the base 10 . As a result, after printing on half the circumferential surface of the cylinder 2 placed on the mounting table 11, the cylinder 2 can be rotated halfway (rotated by 180°) to print on the other half of the circumferential surface. Alternatively, the mounting table 11 may be fixed and the cylinder 2 may be rotated manually. Further, even when the mounting table 11 is rotatable, it may be manually rotated or rotated by a driving means.

The fixing means 12 is vertically movably held by a column 21 erected on the side of the mounting table 11 of the base 10 , and is held by a rotatable arm portion 22 and the arm portion 22 to be mounted on the mounting table 11 . It has a holder member 23 to be fitted on the top of the cylinder 2 to be placed. The holder member 23 can be replaced by an attachment system according to the shape and size of the upper portion of the cylinder 2 .

The carriage 14 is reciprocally movable in a first direction (Y direction) along the height direction of the cylinder 2 mounted on the mounting table 11 and a second direction (X direction) perpendicular to the axis of the cylinder 2. are placed. In this embodiment, the columnar member is the cylinder 2 having an arcuate side surface, and the second direction (X direction) is parallel to the tangent line of the arcuate shape in a plane perpendicular to the first direction (Y direction). direction.

In this embodiment, the slider member 16 is held movably in the Y direction between the support posts 51, 51 of the frame member 15 erected on the side of the mounting table 11 of the base 10, and the carriage 14 is attached to the slider member 16 in the X direction. is held so that it can be moved to

A vertical movement mechanism (Y-direction scanning mechanism) 17 for vertically moving the slider member 16 in the Y direction and a carriage movement mechanism (X-direction scanning mechanism) 18 for moving the carriage 14 in the X direction are provided.

The vertical motion mechanism 17 has, for example, a screw type rotational movement mechanism 71 and a vertical movement motor (Y-direction motor) 72 , and the screw type rotational movement mechanism 71 is connected to the slider member 16 . By rotationally driving the Y-direction motor 72 of the vertical movement mechanism 17 , the slider member 16 is vertically moved in the Y direction via the screw-type rotational movement mechanism 71 .

The carriage moving mechanism 18 also has a screw-type rotary moving mechanism and a lateral movement motor (X-direction motor) 82, and by rotating the X-direction motor 82, the carriage 14 reciprocates in the X direction. .

In addition, the struts 51, 51 of the frame member 15 are connected by a connecting member 52, and along the guide grooves 53, 53 provided in the base 10, the third direction (Z direction).

A Z-direction moving mechanism 19 is provided for reciprocating the frame member 15 in the Z-direction. The Z-direction moving mechanism 19 is an advance/retreat means for moving the discharge unit 13 in the advance/retreat direction with respect to the mounting table 11 .

The Z-direction movement mechanism 19 also has, for example, a screw-type rotation movement mechanism 91 and a forward/retreat motor (Z-direction motor) 92 , and the screw-type rotation movement mechanism 91 is connected to the connection member 52 of the frame member 15 . By rotationally driving the Z-direction motor 92 of the Z-direction movement mechanism 19, the frame member 15 moves in the Z direction via the screw-type rotation movement mechanism 91, and the carriage 14 advances and retreats with respect to the mounting table 11 in the Z direction. move.

Next, an overview of the control unit in this liquid ejecting apparatus will be described with reference to the block diagram shown in FIG.

The control unit 500 includes a CPU 501 that controls the entire apparatus 1, a ROM 502 that stores a program for causing the CPU 501 to control the printing operation and other fixed data, and a RAM 503 that temporarily stores print data and the like. A main control unit 500A is provided.

The control unit 500 has an I/F 506 for transmitting and receiving data and signals used when receiving print data from the host 600 . The host 600 is composed of an information processing device such as a personal computer.

The control section 500 includes a head driving section 508 that drives the head 300 that constitutes the ejection unit 13 .

The control unit 500 includes a motor drive unit 510 that drives the Y direction motor 72 that moves the carriage 14 on which the head 300 is mounted in the Y direction, and a motor drive unit that drives the X direction motor 82 that moves the carriage 14 in the X direction. A portion 511 is provided.

The control unit 500 includes a motor drive unit 512 that drives the Z direction motor 92 that moves the carriage 14 in the Z direction via the frame member 15 . The control unit 500 also includes a motor drive unit 513 that drives the mounting table motor 25 that rotates the mounting table 11 .

The controller 500 includes a cleaning controller 514 that drives and controls a later-described cleaning mechanism 200 that cleans the head 300 .

Next, the printing operation (drawing operation) for the cylinder 2 by the apparatus 1 for ejecting liquid will be described.

First, the print range and print data will be described with reference to FIGS. 5 and 6. FIG. FIG. 5 is an explanatory diagram for explaining the relationship between the print range and the print data, and FIG. 6 is an explanatory diagram for explaining an example of divided print areas when printing is performed over the entire periphery of the cylinder 2. FIG.

In this embodiment, the cylinder 2 is in a stopped state (here, in a fixed state), and when the head 300 is moved in the first direction (Y direction), the liquid is ejected and printed (drawn). No liquid is ejected when moving in the direction (X direction).

Here, when printing on the stopped cylinder 2, as shown in FIG. less than half of the area. At this time, the moving distance Lx of the carriage 14 becomes shorter than the diameter D of the cylinder 2 .

In addition, the diameter of the cylinder 2 varies depending on the cylinder 2, the distance from the head 300 to the peripheral surface of the cylinder 2 varies depending on the cylinder 2, and the distance from the head 300 to the peripheral surface of the cylinder 2 affects the impact accuracy of the flying liquid. receive.

Therefore, when printing is performed around the cylinder 2, a plurality of divided print areas, for example, three divided print areas La to Lc, are set in the circumferential direction. Then, when the printing of one divided print area is completed, the mounting table 11 is rotated so that the next divided print area of the cylinder 2 can face the head 300 and the printing is performed.

Note that the divided print areas do not have to have the same length in the circumferential direction, and are preferably separated by a blank portion between drawings, for example, an area that does not have a drawn image or the like at any position in the Y direction.

Next, the control of the printing operation (drawing operation) by the control unit will be described with reference to FIGS. 7 and 8. FIG. FIG. 7 is a flowchart for explaining the control of the drawing operation, and FIG. 8 is an explanatory diagram of the trajectory of the head in different printing operations.

First, the cylinder 2 is placed on the mounting table 11 and the upper part of the cylinder 2 is fixed by the fixing means 12 .

Then, referring to FIG. 7, the X-direction motor 82, Y-direction motor 72 and Z-direction motor 92 are rotationally driven to move the carriage 14 in the X, Y and Z directions, moving the head 300 to a predetermined drawing start position. (printing start position: writing position) (step S1, hereinafter simply referred to as "S1").

Here, it is assumed that printing (drawing) is performed from the top to the bottom of the cylinder 2, the head 300 has the upper position in the Y direction as the home position, and moves the head 300 from the home position to the drawing start position of the cylinder 2 placed. Moving.

After that, the head 300 starts moving downward in the Y direction (S2), the head 300 starts ejecting liquid (S3), performs predetermined drawing, and stops moving the head 300 downward in the Y direction. (S4).

Here, it is determined whether or not drawing is finished (printing is finished) (S5).

Then, if the drawing is not finished, it is determined whether or not the drawing of one divided print area is finished (S6).

At this time, if drawing of one divided print area has not been completed, the head 300 is moved in the X direction by a predetermined distance (for example, 3.2 mm) (S7), and movement of the head 300 upward in the Y direction is started ( S8), the upward movement of the head 300 in the Y direction is stopped when the head 300 has moved a predetermined amount (S9). After that, the process returns to step S2 to draw the next line.

On the other hand, when the drawing of one divided print area is completed, the table 11 is rotated to bring the next divided print area to a printable position (S10). Thereafter, the process returns to step S1 to continue printing at the drawing start position.

Then, when the drawing ends in step S5, the drawing operation is terminated.

As described above, in the present embodiment, liquid is ejected from the head 300 when the head 300 is moved in a predetermined one direction (one direction) in the Y direction, as indicated by the locus a in FIG. unidirectional printing is performed. In this unidirectional printing, liquid is not ejected from the head 300 when moving in a direction opposite to a predetermined one direction (one direction).
print as required.

By performing such unidirectional printing, it is possible to prevent the image quality from being affected by the force applied to the liquid ejected from the head 300 in the gravitational direction (downward in the Y direction).

On the other hand, when bi-directional printing is performed, the head 300 is moved from top to bottom in the Y direction to eject the liquid onto the circumferential surface of the cylinder 2 as indicated by the trajectory b in FIG. 8(b). print. When scanning from top to bottom in the Y direction is completed, the head 300 is moved in the X direction by a predetermined distance, and printing is performed while moving the head 300 from bottom to top in the Y direction.

This bi-directional printing can improve productivity.

As described above, the head 300 as a liquid ejecting means has a first direction Y and a plane orthogonal to the first direction Y when the vertical direction of the columnar member placed on the mounting table 11 is defined as a first direction Y. are arranged so as to be able to reciprocate in the second direction X along the tangential direction of the columnar member.

As a result, printing (drawing) can be performed by ejecting the liquid onto the peripheral surface of the columnar member while the columnar member is not rotating. and the liquid ejecting means, a high image quality can be printed.

Further, in this embodiment, the upper portion of the cylinder 2, which is a columnar member, is fixed by the fixing means 12. As shown in FIG. As a result, printing can be performed while the attitude of the cylinder 2 mounted on the mounting table 11 is fixed, and high-quality images can be printed more stably.

In this case, in this embodiment, since the liquid is not discharged while the cylinder 2 is rotated, it is not necessary to fix the upper part of the cylinder 2 if the attitude of the cylinder 2 is stable. Further, for example, the attitude maintaining means for maintaining the attitude of the cylinder 2 is not limited to the fixing means for fixing the upper portion. For example, if the cylinder 2 is made of a material that can be magnetically attracted, an electromagnet may be arranged on the mounting table 11, or if the cylinder 2 can be attracted by suction, the mounting table 11 may be provided with a suction means.

Here, a cylinder is used as an example of a columnar member to be printed by a device for ejecting liquid, but the printing can also be performed on a columnar member other than a cylinder, or on a columnar member other than a cylindrical member, such as a prismatic member. can be done.

Next, an example of the ejection unit in the first embodiment will be described with reference to FIGS. 9 to 11. FIG. 9 is a perspective explanatory view of the ejection unit, FIG. 10 is a side explanatory view of the same, and FIG. 11 is a front explanatory view of the head portion.

The ejection unit 13 has a head portion (liquid ejection portion) 30 for ejecting liquid, and the head portion 30 is integrally provided with a cleaning mechanism portion 200 including a wiping member 201 for wiping a nozzle surface 302a which is an ejection surface. ing.

In the head section 30, a holder member 31 holds a plurality (here, three) of heads 300 (300A to 300C) that eject liquids of different colors. The head 300 has a plurality of nozzles 302 for ejecting liquid arranged therein, and the arrangement direction of the nozzles 302 is inclined with respect to the Y direction and held by a holder member 31 serving as a housing.

The cleaning mechanism unit 200 includes a wiping member 201 that wipes the nozzle surface 302 a of the head 300 , and a cleaning liquid ejection unit 202 that is a cleaning liquid application unit that ejects or drops a cleaning liquid 220 (described later) onto the nozzle surface 302 a of the head 300 to apply the cleaning liquid. It has

The wiping member 201 and cleaning liquid discharger 202 are attached to and held by a moving member 205 .

On the other hand, on both sides of the holder member 31 of the head portion 30, guide members 206, 206 having guide grooves 206a are attached. A support shaft 205a of the moving member 205 is movably fitted in the guide groove 206a of the guide member 206. As shown in FIG. That is, the holder member 31 is a housing that holds the head 300 and supports the moving member 205 so as to be movable.

Accordingly, the moving member 205 can move along the guide groove 206a between a position where the wiping member 201 faces the nozzle surface 302a of the head 300 and a position where the wiping member 201 retreats from the nozzle surface 302a.

A rotary air cylinder 210 is provided as driving means for moving the moving member 205 . A long hole 211a provided at the other end of an arm 211 having one end attached to a rotary air cylinder 210 and a pin member 205b provided on the side surface of a moving member 205 are movably fitted. The driving means may be attached to the carriage 14 side, and the ejection unit 13 may be configured to receive the driving force from the carriage 14 side.

As a result, the rotary air cylinder 210 is driven to rotate the arm 211 in the direction of arrow A in FIG. It moves as indicated by an arrow B from the position to the wiping end position, which is also the opposite position indicated by the solid line. This movement of the moving member 205 allows the wiping member 201 to wipe the nozzle surface 302 a of the head 300 .

Thus, the ejection unit 13 integrally includes the head section 30 as a liquid ejection section for ejecting liquid and the cleaning mechanism section 200 for wiping and cleaning the nozzle surface 302a of the head 300 of the head section 30 .

As a result, regardless of the position of the ejection unit 13, the nozzle surface 302a of the head 300 can be wiped and cleaned when liquid is not being ejected, and the ejection surface ( nozzle surface) can be cleaned at any time.

Next, a cleaning liquid supply system for the cleaning mechanism section 200 and a cleaning operation control system will be described with reference to FIG. FIG. 12 is an explanatory diagram for the same explanation.

A cleaning liquid tank 221 , which is a cleaning liquid storage means in which cleaning liquid 220 is stored, is provided. The cleaning liquid tank 221 is connected to the compressor 230 via a path 231 including an air regulator 232 and supplied with pressurized air from the compressor 230 .

Also, the cleaning liquid tank 221 is connected to the cleaning liquid discharge section 202 via a path 233 , and the path 232 is provided with an on-off valve 234 .

On the other hand, the rotary air cylinder 210 is connected to the compressor 230 via a path 241 including an air regulator 242 and supplied with pressurized air from the compressor 230 . An on-off valve 244 is provided in the path 241 .

When the nozzle surface 302a of the head 300 is wiped by the wiping member 201 of the cleaning mechanism 200, the cleaning control unit 514 of the control unit 500 described above controls the opening and closing of the open/close valve 244 to drive the rotary air cylinder 210. As described above, the moving member 205 is moved from the retracted position to the wiping end position.

At this time, the opening/closing valve 234 is controlled to open and close, and the cleaning liquid 220 is ejected from the cleaning liquid ejection section 202 as needed or always to apply the cleaning liquid to the nozzle surface 302a of the head 300, while wetting the wiping member 201. Dispel.

The control timing of the wiping operation by the control unit 500 is, for example, when the discharge unit 13 (head 300) is returned to the home position, or when the discharge unit 13 is moved in the X direction when performing unidirectional printing. It can be performed at any timing when the liquid is not ejected.

When performing the wiping operation, the ejection unit 13 is moved in the Z direction to secure a space between the head 300 and the cylinder 2 for the moving member 205 to enter.

Next, an example of the head in the first embodiment will be described with reference to FIG. 13. FIG. FIG. 13 is a cross-sectional explanatory view of one nozzle portion of the head. Note that FIG. 13(a) shows a state in which the nozzles are closed, and FIG. 13(b) shows a state in which the nozzles are open.

The head 300 includes a hollow housing 304 provided with a nozzle 302 for discharging liquid at its tip and an injection port 303 for injecting liquid near the nozzle 302 .

The housing 304 contains a piezoelectric element 305 that expands and contracts according to the application of voltage from the outside, a valve body 307 that opens and closes the nozzle 302 , and a valve body 307 that is disposed between the valve body 307 and the piezoelectric element 305 . A valve element moving means 308 for moving back and forth with respect to the nozzle 302 is arranged.

The piezoelectric element 305 is housed in a case 315 and is connected to a pair of wiring members 310a and 310b for voltage application and led out to the outside.

A sealing member 306 is arranged between the valve body 307 and the housing 304 to prevent the pressurized liquid injected from the injection port 303 from entering the piezoelectric element 305 side. Thus, a liquid chamber 309 into which the pressurized liquid is injected from the injection port 303 is formed.

The housing 304 is a tubular body such as a cylinder or square tube, and is closed except for the nozzle 302 and the injection port 303 . The nozzle 302 is an opening at the tip of the housing 304 and ejects the liquid 311 . An inlet 303 is provided in the side of the housing 304 near the nozzle 302 and is continuously supplied with pressurized liquid.

The piezoelectric element 305 is formed using zirconia ceramics or the like. A driving waveform (driving voltage) is applied to the piezoelectric element 305 via wiring members 310a and 310b.

The sealing member 306 is, for example, a packing, an O-ring, or the like. By fitting the sealing member 306 to the valve body 307, the liquid is prevented from flowing from the injection port 303 side to the piezoelectric element 305 side. .

The valve body moving means 308 has a deformable portion 308a having a substantially trapezoidal cross-section and is made of a resiliently deformable elastic member made of rubber, soft resin, thin metal plate, or the like. A connection portion 308e corresponding to the upper side of the substantially trapezoidal cross section of the deformed portion 308a is fixed to the base end side surface of the valve body 307. As shown in FIG. The long side corresponding to the base of the substantially trapezoidal cross section of the deformed portion 308a is connected to the bent side portion 308d. The bent side portion 308d is connected to the guide portion 308c at its radial center portion, and is connected to a fixed portion 312 having one end connected to the case 315 between the radial center portion and the end portion.

In this valve body moving means 308, a predetermined voltage is applied to the piezoelectric element 305 and the piezoelectric element 305 expands, so that the guide portion 308c moves toward the nozzle 302 by a distance e, as shown in FIG. 13(b). It moves, and the vicinity of the central portion of the curved side portion 308d is pushed.

At this time, since the outer peripheral side of the guide portion 308c is connected to the fixed portion 312, the curved side portion 308d is displaced in the direction of the arrow with the connecting portion with the fixed portion 312 as a starting point. As the bent side portion 308d is displaced in the direction of the arrow, the deformed portion 308a expands, so that the connection portion 308e with the valve body 307 is pulled in the direction of the arrow.

Due to the deformation of the deformation portion 308a of the valve body moving means 308, the valve body 307 fixed to the connecting portion 308e of the deformation portion 308a is retracted by the distance d, and the nozzle 302 is opened.

In other words, the extension of the piezoelectric element 305 causes the guide portion 308c to move toward the nozzle 302 by a distance e, so that the valve body 307 moves only a distance in the direction opposite to the moving direction of the guide portion 308 (extending direction of the piezoelectric element 305). do.

Here, by adjusting the distance between the connecting portion 308e with the valve body 307 and the curved side portion 308d and the length of the curved side portion 308d in the deformation portion 308a of the valve body moving means 308, the amount of movement of the valve body 307 can be adjusted. It can be longer than the displacement amount of the piezoelectric element 305 .

That is, the valve body moving means 308 can amplify the amount of displacement of the piezoelectric element 305 and can reduce the amount of displacement of the piezoelectric element 305, so that the piezoelectric element 305 can be miniaturized.

Next, the operation of the head 300 will be described with reference to FIG. 14 as well. FIG. 14 is an explanatory diagram of an example of drive voltages used for explaining the operation.

In the head 300 , the piezoelectric element 305 is in a contracted state when no voltage is applied to the piezoelectric element 305 , so no force is applied to the valve body moving means 308 by the piezoelectric element 305 . At this time, the deformed portion 308a of the valve body moving means 308 is in a swollen state (normal state) as shown in FIG. is energized by Therefore, the nozzle 302 is closed by the end face of the valve body 307 and the liquid 311 is not discharged from the nozzle 302 .

Here, as shown in FIG. 14(a), a voltage (+EV) having a waveform P1 is applied to the piezoelectric element 305, whereby the piezoelectric element 305 expands, and as described above, the valve body moving means 308 The deformable portion 308a is deformed to retract the valve body 307 in the direction of the arrow shown in FIG. 13(b). As a result, the valve body 307 opens the nozzle 302 , and the pressurized liquid injected from the inlet 303 is discharged from the nozzle 302 .

On the other hand, as shown in FIG. 14(b), a waveform P2 in which the voltage (+EV) of the waveform P2 to the piezoelectric element 305 disappears in the middle is applied, or a waveform P2 that should be applied as shown in FIG. 14(c) is applied. A waveform voltage may not be applied to the piezoelectric element 305 due to a power failure or the like.

At this time, since the piezoelectric element 305 maintains the contracted state, the deformation portion 308a of the valve body moving means 308 returns to the normal state shown in FIG. 13(a). Therefore, since the valve body 307 keeps the nozzle 302 closed, the liquid 311 is not discharged from the nozzle 302 .

As a result, even in the event of a power failure or the like, the liquid 311 can be prevented from accidentally leaking out of the nozzles 302 or clogging the nozzles.

Next, a liquid supply system for head 300 will be described with reference to FIG. FIG. 15 is an explanatory diagram of the same liquid supply system.

Here, liquid tanks 330 (330A to 330C) are provided as airtight containers containing liquids 311 of respective colors discharged from the heads 300 (300A to 300C). The liquid tank 330 and the inlet 303 of the head 300 are connected via tubes 333 respectively.

On the other hand, the liquid tank 330 is connected to a compressor 340 through a pipe 331 including an air regulator 332 and supplied with pressurized air from the compressor 340 .

As a result, the pressurized liquid 311 of each color is supplied to the injection port 303 of each head 300, and the liquid 311 is discharged from the nozzle 302 according to the opening and closing of the valve element 307, as described above.

Next, an example of cleaning processing by the control unit will be described with reference to the flowchart of FIG. 16 .

When the cleaning process is started, the control section 500 starts moving the discharge unit 13 to the retracted position in the Z direction (S21), and completes the movement of the discharge unit 13 to the retracted position in the Z direction (S22). That is, before the wiping operation of wiping the nozzle surface 302a with the wiping member 201 is performed, the ejection unit 13 is retracted in the direction away from the columnar member (cylinder 2) by the advancing/retreating means (Z-direction moving mechanism 19).

After that, the cleaning operation is started by the cleaning control unit 514 (S23).

After the cleaning operation ends, the ejection unit 13 starts to move to the drawing start position (S24), completes the movement of the ejection unit 13 to the drawing start position (S25), and ends the cleaning process.

In the movement of the ejection unit 13 to the retracted position, the cleaning operation, and the return operation to the drawing position, the movements in the X, Y, and Z directions are performed as long as the movement of the moving member 205 in the cleaning operation does not interfere with the cylinder 2. It can also be done in parallel.

Next, an example of cleaning operation control by the cleaning control unit 514 will be described with reference to the flowchart of FIG. 17 .

After starting the cleaning operation, the cleaning control unit 514 starts applying the cleaning liquid 220 from the cleaning liquid ejection unit 202 (S31). Then, the moving member 205 is moved from the retracted position indicated by the phantom line in FIG. 10 toward the wiping position to bring the wiping member 201 into contact with the nozzle surface 302a (S32).

In other words, the cleaning liquid applying means (cleaning liquid ejector 202) applies (discharges or drops) the cleaning liquid 220 before the wiping member 201 contacts the nozzle surface 302a.

After that, the moving member 205 is moved from the wiping position (the upper end of the nozzle surface 302a) to the wiping position (the lower end of the nozzle surface 302a), and the nozzle surface 302a is wiped by the wiping member 201 (S33).

Next, the moving member 205 is moved from the wiping position (lower end of the nozzle surface 302a) to the wiping position (upper end of the nozzle surface 302a), and the wiping member 201 wipes the nozzle surface 302a (S34).

After that, application of the cleaning liquid 220 from the cleaning liquid discharge section 202 is completed (S35). After that, the moving member 205 is moved from the wiping position to the retracted position (S26), and the cleaning operation ends.

In other words, the cleaning liquid application unit (cleaning liquid discharge unit 202) finishes applying (discharging or dropping) the cleaning liquid 220 before the wiping member 201 returns to the retracted position.

The application of the cleaning liquid 220 by the cleaning liquid application means (the cleaning liquid discharge unit 202) can be performed continuously or intermittently from the start of application of the cleaning liquid 220 (S31) to the completion of application (S35).

Next, a second embodiment of the invention will be described with reference to FIG. FIG. 18 is a perspective explanatory view for explaining the discharge unit in the same embodiment.

In this embodiment, the head 300 has a plurality (six here) of nozzle rows 302A in which a plurality of nozzles 302 are arranged.

The cleaning mechanism section 200 includes a cleaning liquid receiver 261 that receives excess cleaning liquid 220 dropped during wiping. A waste liquid tube 262 is connected to the cleaning liquid receiver 261, and the collected waste liquid is discharged to a waste liquid tank or the like.

In each of the above-described embodiments, the wiping member and the cleaning liquid applying section of the ejection unit are held by the moving member and moved together, but the present invention is not limited to this.

For example, a cleaning liquid applying means for applying cleaning liquid is provided at the home position, and the ejection unit is returned to the home position when the cleaning liquid is applied and the wiping operation is performed, and otherwise only the wiping operation is performed without applying the cleaning liquid. can also

In the second embodiment, the cleaning liquid receiver 261 is provided on the discharge unit 13 side, but the cleaning liquid receiver 261 such as a groove member is arranged on the apparatus main body side, and the cleaning liquid receiver 261 is arranged only when the cleaning liquid is applied. It is possible to adopt a configuration in which the cleaning liquid 220 is applied by moving to a position where the cleaning liquid 220 is applied. This eliminates the need for the carriage 14 to move together with the cleaning liquid receiver 261, thereby suppressing an increase in the weight of the carriage 14 as a whole.

Next, a third embodiment of the invention will be described with reference to FIGS. 19 and 20. FIG. FIG. 19 is an explanatory diagram for explaining printing of an aircraft as an object to be printed by the apparatus for ejecting liquid according to the embodiment, and FIG. 20 is a perspective explanatory diagram of the apparatus for ejecting liquid.

The device 1 for ejecting liquid includes a linear rail 404 for linearly moving a carriage on which the ejection unit 13 is mounted, and an articulated robot that moves the linear rail 404 to a predetermined position and holds it at that position. 405.

The articulated robot 405 has a robot arm 405a that can freely move like a human arm through a plurality of joints, and can move the tip of the robot arm 405a freely and place it in an accurate position. be able to.

As the articulated robot 405, for example, a 6-axis control type industrial robot having 6 axes, that is, 6 joints can be used. According to the 6-axis type articulated robot, it is possible to cause the linear rail 404 to face the predetermined position of the printing object 702 (aircraft) very accurately and quickly by teaching the information about the operation in advance. The robot 405 is not limited to 6 axes, and may be an articulated robot having an appropriate number of axes such as 5 axes or 7 axes.

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

Both ends of the linear rail 404 that movably holds the ejection unit 13 are supported by being bridged between two vertical linear rails 423a and 423b.

The ejection unit 13 includes, for example, a plurality of heads 300 for ejecting black, cyan, magenta, yellow, and white liquids, or a head 300 having a plurality of nozzle rows. Each head 300 of the ejection unit 13 or each nozzle row of the head 300 is pressurized and supplied with the liquid of each color from the liquid tank 330 in the same manner as the above-described liquid supply system.

In the apparatus 1 for ejecting liquid, the robot 405 moves the linear rails 404 to a position facing the required printing area of the printing object 702, and the ejection unit 13 is moved along the linear rails 404 according to the print data. While driving the head 300, printing is performed.

When one line of printing is completed, the vertical linear rails 423a and 423b are driven to move the head 300 of the ejection unit 13 from one line to the next line.

This operation can be repeated to print on the desired print area of the print object 702 .

At this time, the ejection unit 13 (head 300) moves a long distance, but the ejection unit 13 includes the wiping member 201 and can clean the nozzle surface 302a of the head 300 at any time.

As a result, high-quality printing can be continuously performed with little downtime.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 21 and 22. FIG. FIG. 21 is a perspective explanatory view of a device for ejecting liquid according to the same embodiment, and FIG. 22 is a perspective explanatory view of a drive section of the same device.

The device 1 for ejecting liquid comprises a movable frame unit 802 that is installed facing a printed object 702 having a curved surface, such as the hood of a vehicle. A movable unit 813 is attached to the left and right frame members 810 and 811 constituting the frame unit 802 so as to be able to move up and down in the vertical direction (Y direction) so as to span the frame members 810 and 811 .

The movable unit 813 includes a drive unit 803 containing a motor arranged so as to be able to reciprocate in the horizontal direction (X direction) on the movable unit 813 , and a drive unit 803 attached to the drive unit 803 that directs the liquid toward the printing object 702 . A discharge unit 13 for discharging is mounted.

In addition, a controller 805 that controls liquid ejection from the ejection unit 13, reciprocating movement of the drive unit 803, and vertical movement of the movable unit 813, and an information processing device 806 such as a PC (personal computer) that gives instructions to the controller 805. and The information processing apparatus 806 is connected to a database unit (DB unit) 807 that records and stores information regarding the print object 702 such as its shape and size.

The frame unit 802 is mounted vertically and horizontally on both sides of upper, lower, left and right frame members 808, 809, 810, and 811 formed of metal columns or the like, and a lower frame member 809 so that the frame unit 802 can stand on its own. left and right leg members 812a and 812b.

A movable unit 813 bridged between the left and right frame members 810 and 811 is configured to be able to move up and down while supporting the drive section 803 .

The print target 702 is arranged perpendicular to the liquid ejection direction (Z direction), that is, facing the plane formed by the upper, lower, left, and right frame members 808 , 809 , 810 , 811 of the frame unit 802 . .

In this case, in order to place the print target 702 at a predetermined position to be printed, for example, the back side of the print area of the print target 702 is sucked and held by a chuck attached to the tip of the arm of the articulated arm robot. It can be done by letting By using the articulated arm robot, it is possible to accurately place the print target 702 at the print position, and to change the posture of the print target 702 as appropriate.

As shown in FIG. 22, the driving section 803 is arranged so as to be reciprocally movable in the horizontal direction (X direction) on the movable unit 813 . The movable unit 813 includes a rail 830 horizontally disposed so as to bridge the left and right frame members 810 and 811 of the frame unit 802, and a rack gear 831 disposed parallel to the rail 830. , a linear guide 832 that is fitted on a part of the rail 830 and moves while sliding, a pinion gear unit 833 that is connected to the linear guide 832 and meshes with the rack gear 831, and a reduction gear that rotationally drives the pinion gear unit 833. It comprises a motor 834 with an 836 and a rotary encoder 835 for detecting the printing point position.

By driving the motor 834 (rotating forward or backward), the discharge unit 13 is moved rightward or leftward along the movable unit 813 . The drive unit 803 functions as a drive mechanism for the ejection unit 13 in the X direction. Limit switches 37a and 37b are attached to both sides of the housing of the speed reducer 836. As shown in FIG.

The ejection unit 13 includes, for example, a plurality of heads 300 for ejecting black, cyan, magenta, yellow, and white liquids, or a head 300 having a plurality of nozzle rows. Each head 300 of the ejection unit 13 or each nozzle row of the head 300 is pressurized and supplied with the liquid of each color from the liquid tank 330 in the same manner as the above-described liquid supply system.

In the device 1 for ejecting liquid, the movable unit 813 is moved in the Y direction and the ejection unit 13 is moved in the X direction to print a desired image on the printing object 702 .

At this time, the ejection unit 13 (head 300) moves a long distance, but the ejection unit 13 includes the wiping member 201 and can clean the nozzle surface 302a of the head 300 at any time.

As a result, high-quality printing can be continuously performed with little downtime.

1 Device for discharging liquid 2 Cylinder (columnar member)
REFERENCE SIGNS LIST 10 base 11 mounting table 12 fixing means 13 ejection unit (liquid ejection means)
14 Carriage 15 Frame Member 16 Slider Member 300 Head 200 Cleaning Mechanism Section 201 Wiping Member 202 Cleaning Liquid Discharge Section 302 Nozzle 305 Piezoelectric Element 307 Valve Body 500 Control Section 702 Object to be Printed

Claims (7)

a head having nozzles for ejecting liquid;
a wiping member for wiping the nozzle surface of the head;
a moving member that holds the wiping member and is movable between a position where the wiping member faces the nozzle surface and a position where the wiping member is retracted from the nozzle surface;
a housing that holds the head and movably supports the moving member;
a discharge unit comprising a cleaning liquid application means for discharging or dropping a cleaning liquid ;
An apparatus for ejecting a liquid, comprising: a moving body that reciprocates, on which the ejection unit is mounted. 2. The apparatus for ejecting liquid according to claim 1, wherein said cleaning liquid applying means is held by said moving member. Equipped with a mounting table for mounting the columnar member,
ejecting the liquid from the head of the ejection unit onto the columnar member;
When the up-and-down direction of the columnar member placed on the mounting table is defined as a first direction, the movable body is arranged in the first direction and in a plane perpendicular to the first direction, and a line tangent to the columnar member. 3. The apparatus for ejecting liquid according to claim 1, wherein the apparatus is arranged to be reciprocatable in a second direction along the direction. an advance/retreat means for moving the discharge unit in a direction to advance/retreat with respect to the mounting table;
4. The apparatus for ejecting liquid according to claim 3 , wherein the advancing/retreating means retracts the ejecting unit in a direction away from the columnar member before performing the wiping operation of wiping the nozzle surface with the wiping member. . 5. The apparatus for ejecting liquid according to claim 3 , wherein the cleaning liquid applying means ejects or drips the cleaning liquid before the wiping member and the nozzle surface come into contact with each other. 6. The apparatus for ejecting liquid according to claim 3 , wherein the cleaning liquid applying means finishes ejecting or dropping the cleaning liquid before the wiping member returns to the retracted position. 7. The apparatus for ejecting liquid according to claim 3 , further comprising a cleaning liquid receiving member for collecting the cleaning liquid.

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