JP3821187B2 - Printing machine and maintenance method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a nozzle wiping device and a wiping method for a printing press using hot melt ink.
[0002]
[Prior art]
The print head purging method using heat-meltable solid ink includes the method of pressurizing the ink chamber of the print head and discharging the ink from the orifice, and the method of pressing the suction unit against the orifice and sucking out the ink directly from the orifice. is there. As an ink chamber pressurizing method, a method of sucking waste ink with a wiping sheet is adopted for a product. Further, as a method for sucking the orifice, there is a method described in JP-A-4-111149.
[0003]
[Problems to be solved by the invention]
However, in the method of sucking the orifice, when the ink is sucked from the orifice, the surface of the orifice is soiled with the sucked ink, or the ink is spilled around the head when the ink is discarded.
[0004]
An object of the present invention is to provide an apparatus and a wiping method for wiping a nozzle surface with a simple configuration, and in particular, to provide a method for preventing ink from spilling around a head.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an ink tank that stores ink, and a nozzle plate that communicates with the ink tank and has a plurality of nozzles provided so as to eject ink as droplets by ink droplet generation means. And an inkjet head composed of a carriage that carries these and moves at an arbitrary position, an image stand that is set up almost vertically, and an arbitrary end on the image base arranged at a position facing the nozzle plate. A printing machine having suction purge means provided and moving means for moving the nozzle plate forward or backward with respect to the suction purge means and moving freely in the horizontal and vertical directions facing the table in a waste ink disposal means for disposing of the ink sucked by said suction purge means, located below the waste ink disposal unit, disposal by the waste ink disposal means With the recovery of waste ink has a suction ink sheet contact surface between the nozzle plate is configured to be movable, and a winding means for winding the absorbent ink sheet, the nozzle plate during the purge operation The ink-absorbing sheet is always brought into contact with a part of the sheet.
[0006]
Here, the ink-absorbing sheet winding means has a driving roller, a driven roller, a pulley, a guide cover that slidably engages both ends or one end of the pulley, and one end locked to the guide cover. The other end is constituted by a spring engaged with one end of the pulley.
[0007]
Alternatively, the ink absorbing sheet take-up means includes a driving roller, a driven roller, a pulley, a guide base formed by rotatably attaching the pulley, the driving roller, and the driven roller, and swinging the guide base. It comprises a fulcrum that enables it, and a spring engaged with the table and the guide base.
[0008]
In these configurations, the contact surface of the ink absorbing sheet with the nozzle plate is configured to be movable in conjunction with the purge operation, so that the wiping efficiency is remarkably improved.
[0009]
A preferable maintenance method in the printing press having the above-described configuration includes the step of moving the ink-jet head at an arbitrary position of the image base to a position facing the suction purge means, and the ink-jet head is advanced in the direction of the suction purge means. A step of bringing only a part of the nozzle plate into contact with the ink-absorbing sheet, a step of further advancing the ink-jet head and bringing the ink-jet head into contact with the suction purge means, and a purge operation being completed Thereafter, the step of retracting the ink jet head from the suction purge means while maintaining the state where the ink absorbing sheet and the nozzle plate are in contact with each other, and the ink jet head in a state where the ink absorbing sheet is in contact with the nozzle plate By moving it downward, the nozzle pre More the step of wiping the ink adhering to the bets.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The configuration of the printing machine 1 is shown in FIG.
[0011]
The printing paper 3 is attached to the front surface of the image stand 2 that is set up almost vertically. An inkjet head 10 that can freely move in the horizontal and vertical directions on the front surface of the printing paper 3 includes a carriage 5, an ink tank 4 attached to the top of the carriage 5, and a nozzle plate 11 that can eject ink to the front surface of the ink tank. It consists of Reference numeral 12 denotes a claw portion, and 14 denotes an ink chamber.
[0012]
6 is a wire for pulling the inkjet head 10 in the horizontal direction, 7 is a guide for holding the inkjet head 10 horizontally, and 9 is a pulley that is supported by the guide 7 and holds the wire 6. Reference numeral 8 denotes a belt for moving the inkjet head in the vertical direction. One end of the guide 7 is attached to the belt 8.
[0013]
30 is a suction purge means, 50 is an ink absorbing sheet take-up means, and 53 is an ink absorbing sheet.
[0014]
1 to 4 are cross-sectional views showing the positional relationship between the inkjet head 10 and the suction purge means 30. 1 shows the state before purging, FIG. 2 shows the state during purging, FIG. 3 shows the state of ink discharge after purging, and FIG. 4 shows the state of nozzle wiping.
[0015]
In the figure, purge means 30 includes an ink case 31, a heater 33 attached to the back of the ink case to heat the ink case, and an elastic body 35 attached to the opening of the ink case at a position facing the nozzle. An intake port 36 opened in the upper part of the ink case, a suction purge pump 38, a hose 37 connecting the purge pump and the intake port 36, and an ink discarding hole for waste ink processing opened in the lower part of the ink case 32.
[0016]
The elastic body 35 is made of silicone rubber, has heat resistance, and is soft. 35a is a contact surface with the nozzle plate, and 35b is a protrusion, which is on the same surface as the contact surface 35a or at a position slightly protruding from the contact surface. The valve portion 35 c is disposed on the extension of the protruding portion 35 b and below the ink discard hole 32.
[0017]
The ink sheet winding means 50 includes a driving roller 51, a driven roller 52, and a pulley 54 that faces the nozzle plate 11 and is arranged with a slight gap before purging. The ink sheet 53 is wound around the driven roller 52 and attached so as to be wound around the driving roller 51 through the pulley 54. Further, an ink discard hole 32 of the ink case is disposed above the ink sheet 53 between the pulley 54 and the driving roller 51.
[0018]
The operation will be described below.
[0019]
If there is an abnormality in the ink ejection from the nozzles during printing or non-printing, the inkjet head 10 on the table is moved to a position facing the suction purge means 30 (FIG. 1). However, the ink absorbing sheet 53 is not in contact with the nozzle surface 11 at this time.
[0020]
Next, the ink tank 4 and the nozzle plate 11 are advanced in the direction of the suction purge means 30 by a moving means (not shown). The nozzle plate 11 is in close contact with the contact surface 35a of the elastic body 35 and simultaneously presses the protrusion 35b of the elastic body. As a result, the valve portion 35c on the extension of the protrusion 35b is provided in the lower part of the ink case 31. The discard hole 32 can be closed (FIG. 2).
[0021]
Further, in this configuration, before the nozzle plate 11 moves forward and contacts the suction purge means 30, the lower portion of the nozzle plate 11 and the ink absorbing sheet 53 come into contact with each other. When the nozzle plate 11 further advances and the nozzle plate 11 comes into contact with the suction purge means 30, the pulley 54, which is a part of the ink absorbing sheet take-up means 50, is pushed by the nozzle plate to the right in the figure. Move to. In this way, by moving only the pulley of the ink sheet, the movable portion can be suppressed to a small range as compared with the case where the entire ink sheet winding means is swung. Further, by making the winding direction of the ink sheet substantially perpendicular to the external force at the time of pressing, it is possible to suppress a significant decrease in the contact pressure between the head and the ink sheet when winding the ink sheet.
[0022]
When the suction purge pump 38 is driven in a state where the ink discard hole 32 is closed by the valve portion 35C, that is, in the state shown in FIG. 2, ink is sucked from the nozzle plate 11 and stored in the ink case 31.
[0023]
Next, the ink tank 4 and the nozzle plate 11 are moved backward by the moving means. When the nozzle plate 11 is retracted to a position where it does not come into contact with the elastic projection 35 b, the valve portion 35 c that has blocked the ink discard hole 32 returns to its original state by the restoring force, and the waste that has accumulated in the ink case 31. The ink can be discharged to the ink sheet 53 through the ink discard hole 32 (FIG. 3). At this time, if the driving roller 51 is moved in synchronization with the timing of discarding the waste ink, the waste ink on the ink sheet can be wound up to a substantially uniform thickness. However, also at this time, the ink absorbing sheet 53 is set to a position where it contacts the nozzle plate 11.
[0024]
As shown in FIG. 4, the ink attached to the nozzle plate 11 can be wiped off by moving the inkjet head 10 downward. At this time, if the ink-absorbing sheet 53 is wound up in accordance with the movement of the inkjet head, the nozzles can be wiped more efficiently.
[0025]
FIG. 5 shows the pulley portion 54 of the ink absorbing sheet take-up means for enabling the above operation.
[0026]
In the figure, the guide cover 56 is formed with grooves 57 that support both ends of the pulley 54. Further, a spring 58 having one end engaged with the pulley 54 and the other end engaged with the guide cover is attached to the groove 57. Accordingly, when the inkjet head 10 (not shown) on the left side of the pulley 54 in the drawing is pressed to the right in the drawing along with the purge operation, the pulley 54 may move to the right along the groove 57. it can.
[0027]
As described above, in this configuration, only the pulley 54 can be moved together with the nozzle plate 11 to perform a series of purge operations.
[0028]
FIG. 6 shows another configuration of FIG. 5, and the purge operation can be performed by moving the entire ink-absorbing sheet winding means 50.
[0029]
In the figure, 61 is a driving roller, 62 is a driven roller, 64 is a pulley, 66 is a guide base for supporting the driving roller, the driven roller and the pulley, 67 is a fulcrum for swinging the guide base, and 68 is a part of the stand. It is a spring for engaging the part 2a and the guide base.
[0030]
In the drawing, the inkjet head 10 (not shown) is disposed on the left side of the pulley 64. When the ink jet head 10 moves to the right, the nozzle plate 11 pushes the pulley 64 through the ink absorbing sheet 53, so that the entire ink absorbing sheet winding means 50 rotates around the fulcrum 67 (operation of FIG. 2). When the nozzle plate is moved to the left in the drawing, the ink absorbing sheet take-up means 50 can return to the original state by the restoring force of the spring 68.
[0031]
【The invention's effect】
As described above, according to the present invention, the nozzle surface can be wiped with a simple configuration, and ink can be prevented from spilling around the head during a series of purge operations.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a purge operation of a printing press according to the present invention.
FIG. 2 is a cross-sectional view showing a purge operation of the printing press of the present invention.
FIG. 3 is a cross-sectional view showing a purge operation of the printing press of the present invention.
FIG. 4 is a cross-sectional view showing a purge operation of the printing press of the present invention.
FIG. 5 is a perspective view showing a part of the configuration of the ink-absorbing sheet winding means of the present invention.
FIG. 6 is a perspective view of an ink-absorbing sheet winding unit as another example of the present invention.
FIG. 7 is a perspective view showing the overall configuration of the printing press of the present invention.
[Explanation of symbols]
1 is a printing machine, 4 is an ink tank, 5 is a carriage, 11 is a nozzle plate, 30 is a suction purge means, 31 is an ink case, 50 is an ink-absorbing sheet winding means, 51 is a drive roller, 52 is a driven roller, 53 Is an ink absorbing sheet, 54 is a pulley, 61 is a driving roller, 62 is a driven roller, 64 is a pulley, 66 is a guide base, and 67 is a fulcrum.

Claims (5)

An ink tank that stores ink, a nozzle plate that communicates with the ink tank and has a plurality of nozzles provided to eject ink as droplets by means of ink droplet generation, and these are mounted and moved to any position An ink jet head composed of a carriage to be moved, a substantially vertical stand, a substrate to be fixed to the stand, and an arbitrary end on the stand at a position facing the nozzle plate. In a printing machine that has a suction purge means that is moved, and a moving means that moves the nozzle plate forward or backward relative to the suction purge means, and that moves freely in the horizontal and vertical directions facing the table ,
A waste ink discarding unit for discarding the ink sucked by the suction purge unit; a waste ink disposed at a position below the waste ink discarding unit for collecting the waste ink discarded by the waste ink discarding unit; A structure having an ink-absorbing sheet whose contact surface is movable and a winding means for winding the ink-absorbing sheet, and the ink-absorbing sheet is always in contact with a part of the nozzle plate during the purge operation A printing machine characterized by Oite to claim 1, wherein the printing machine,
The ink absorbing sheet winding means includes a driving roller, a driven roller, a pulley, a guide cover that slidably engages both ends or one side of the pulley, one end locked to the guide cover, and the other end And a spring engaged with one end of the pulley . Oite to claim 1, wherein the printing machine,
The ink sheet winding means includes a driving roller, a driven roller, a pulley, a guide base that is rotatably attached to the pulley, the driving roller, and the driven roller, and the guide base is made swingable. A printing machine comprising a fulcrum and a spring engaged with an image base and the guide base . Oite the printing machine according to any one of claims 1 to 3,
A printing machine , wherein a contact surface of the ink absorbing sheet with the nozzle plate is movable in conjunction with a purge operation . Oite the printing machine according to any one of claims 1 to 4,
A step of moving the ink-jet head at an arbitrary position on the table to a position facing the suction purge means; and advancing the ink-jet head in the direction of the suction purge means; A step of bringing only the sheet into contact, a step of further advancing the ink jet head, bringing the ink jet head and the suction purge means into contact with each other, and purging, and after the purge operation, the ink absorbing sheet and the nozzle plate are The step of retracting the ink-jet head from the suction purge means while maintaining the contact state, and the ink-jet head is attached to the nozzle plate by moving the ink-jet head downward with the ink-absorbing sheet in contact with the nozzle plate. The process of wiping off the used ink Maintenance method for a printing press to be butterflies.

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