JPH09239969A - Printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a performance of a discharging nozzle over a long period by guiding a move of two or more discharging nozzles to a first and second position and, setting the first position as a position to print a printing medium and the second position as a wiping position to wipe two or more discharging nozzles by a wiping means. SOLUTION: When a power source is put on, and until a device is stabilized, a head part 41 moves to a lower part and a supporting member 42a of an electrode part 42, a main body 45a of a cap part 45 and a main body 46a of a wipe part 46 move to a stand-by position side which is a downstream of a head part 41 of an each slide shaft in a carrying direction of a print medium C. Next, after a supporting member 41a of a head part 41 has moved to a wipe position along with a slide shaft, the main body 46a of the wipe part 46 moves forward along with the slide shaft and the wiper 46b moves to wipe a discharging nozzle surface of the head unit. And, after the wipe part 46 moves to the stand-by position, the head part 41 moves downward to a printing position and the electrode part 42 moves forward to directly below the head part 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus that prints on a sheet-shaped print medium.

[0002]

2. Description of the Related Art As a means for drawing pictures, characters, and the like on a sheet-like print medium, it is possible to shorten the time from pattern determination to completion, instead of conventional screen printing. An ink jet system has been adopted, which has many advantages such as easy change of pattern and furthermore, high-mix low-volume production.

However, in the ink jet method, since ink droplets are ejected from the ejection nozzles to draw a pattern or the like on the print medium, a large number of ejection nozzles are required when applied to a large sheet-shaped print medium, The performance of each discharge nozzle must be maintained for a long period of time so that proper drawing can be performed, and this is not always satisfactory in terms of maintainability.

The present invention has been made in view of the above points, and an object of the present invention is to provide a printing apparatus capable of maintaining the performance of a large number of ejection nozzles for a long period of time and having excellent maintainability.

[0005]

In order to achieve the above object, a printing apparatus of the present invention is a printing apparatus for printing a print medium with ink droplets ejected from a plurality of ink jet type ejection nozzles. Guide means for guiding and fixing the movement of the plurality of discharge nozzles to the first and second positions is provided, and the first position is a position for printing on the print medium, and the second position.
The position is the position where the wiping operation is performed to wipe the nozzle surfaces of the plurality of discharge nozzles with the wiping means.

[0006] Preferably, the print medium is provided with a transport means for transporting the print medium in the horizontal direction. Further preferably, the guide means moves the plurality of discharge nozzles in the vertical direction. More preferably, a cap means for covering the nozzle surface is provided, and a position for performing the cap operation is a third position different from a position for performing the wipe operation in the second position.

Preferably, the wiping means is arranged along the arrangement direction of the plurality of ejection nozzles and has a length equal to or larger than the width of the print medium. Further preferably, the cap means has a seal member having a triangular cross section. More preferably, it is provided with a first guide member that is arranged in parallel with the transport direction of the print medium and that guides the wiping operation of the wipe means along the transport direction.

Preferably, a second guide member is provided which is arranged in parallel with the conveying direction of the print medium and guides the cap operation of the cap means along the conveying direction. Further preferably, the first position is positioned by bringing a part of a structure for carrying the print medium into contact with a part of a head portion having the plurality of ejection nozzles.

More preferably, the plurality of ejection nozzles are provided with adjusting means for adjusting the position in the thickness direction according to the thickness of the print medium. Preferably, the plurality of discharge nozzles are assembled into a head unit in which a predetermined number of discharge nozzles are linearly arranged on the same plane, and a plurality of units are arranged in a width or more orthogonal to the transport direction of the print medium. The configuration is

Further, preferably, the head unit is provided with a rail for pulling out the head unit in a direction orthogonal to the conveying direction of the print medium.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
It will be described in detail with reference to FIG. FIG. 1 is a perspective view showing a schematic configuration of a printing apparatus of the present invention. The printing apparatus 1 includes an introduction unit 2, a conveyance unit 3, a printing unit 4, a preliminary drying unit 5, a drying unit 6, and a shake-off unit 7, as well as a data creation / editing unit, a color adjustment unit, an image data storage unit, and an unillustrated data storage unit. It has a fixing unit.

As shown in FIG. 1, the introducing unit 2 positions a sheet-shaped print medium, for example, a roll or a cloth C accommodated in a box 2a, at least in the wrinkle-stretching and centering direction by a plurality of rolls 2b. It is a portion to be introduced into a predetermined position of the transport unit 3 while performing centering, correction of the texture and curl correction of both ends (both ears of the cloth C). The cloth C is preliminarily subjected to chemical bleeding prevention processing or the like in order to maintain the quality in the drawing processing of a picture or a character.

The transport unit 3 is disposed adjacent to the introduction unit 2, and has a transport belt 3b laid between the rolls 3a, 3a, a plurality of stages of adhesive application rolls 3c, and a plurality of brush rolls (belt surface cleaning) 3d. And the cloth C introduced from the introduction section 2
Is transported to the printing unit 4 side by the transport belt 3b. The transport unit 3 includes a plurality of adhesive application rolls 3
c, an adhesive is applied to the conveyor belt 3b,
Of the cloth C introduced from the conveyor belt 3 by the pressing roll 3e.
It is pressed against b, stuck, and conveyed in this state. A water-based or oil-based adhesive is used. The plurality of brush rolls 3d are used when removing the adhesive on the conveyor belt 3b. In the transport section 3, the fabric C is transported by the transport belt 3
So that the state stuck to b is the steady state of the fabric C,
The tension of the cloth C is adjusted, the meandering is adjusted, and the texture is adjusted.

Here, in the case where the cloth C is a highly stretchable cloth, if the cloth C is attached to the conveyor belt 3b in a state where the tension is uneven, the cloth C is peeled from the conveyor belt 3b, or the printed cloth C is conveyed. When removed from 3b, the drawing is distorted, such as the circular pattern becoming an ellipse.
In an extreme case, the cloth C is transported by the transport belt 3b in an extreme case.
Or the pattern of the cloth C and the pattern of the cloth C are not aligned,
It must be avoided because it will hinder the cutting and sewing process. Further, in the printing apparatus 1 of the present invention, the fabric C is not in contact with other members except the transport belt 3b in the printing process, as compared with the conventional screen printing apparatus.
For this reason, when the adhesive is transferred, the cloth C is transferred by the transfer belt 3b.
It is sufficient to have an adhesive force enough to maintain a relative position that does not move, and an adhesive force is not so necessary.

The print unit 4 is a portion for drawing a picture, a character, or the like on the cloth C by a continuous type ink jet system, and is arranged to face the cloth C at a width larger than the width of the cloth C so as to be orthogonal to the conveying direction. It has a plurality of rows of line heads 40 corresponding to. Here, the line head 4
The configuration of 0 will be described in detail later. Although the line head 40 has eight rows in FIG. 1, it is also possible to use a line head having a large number of rows in order to improve color reproducibility.
Usually, for example, a line head for four colors of cyan (C), yellow (Y), magenta (M), and black (K), or a line head for a total of eight colors including the shades of these CYMKs, It is possible to devise in operation, such as preparing two line heads for replacing ink depending on the design.

The predrying section 5 is a section for drying at least 20% or more of the evaporation component in the ink from the printed cloth C by a heater or the like. As shown in FIG. 1, the fabric C printed by the printing unit 4
Is peeled off from the transport belt 3b by the tension applied from the tension roll 5a downstream of the printing unit 4.
At this time, the printed fabric C may lose its ink if it touches a surrounding member, for example, the tension roll 5a, before the evaporation component in the ink droplet is dried by a predetermined amount.
Drying treatment is performed for the purpose of preventing such fainting, because the color mixing is not preferable.

The drying section 6 is a section for further drying the evaporation component in the ink from the cloth C dried in the preliminary drying section 5 by 85% or more. On the other hand, the data creation and editing department
A so-called CAD including an input means for inputting a picture or a character drawn on a print medium (cloth C) and an editing means for editing image data relating to the inputted picture, a character, etc.
Image data is transmitted by optical communication with an image data storage unit, which will be described later, provided in each line head 40.

The color adjusting section is a section for color-separating the image data relating to the edited picture or character into image data for each predetermined color, and for the image data such as the picture created by the data creating / editing section, It also has a function of correcting image data for each color so that a pattern or the like drawn on a print medium (cloth C) with a limited number of colors of ink reproduces the hue and texture more accurately.

The image data storage section is a buffer section for storing the color-separated image data, and is a position where the printing apparatus can be operated in the shortest time, for example, each line head 40.
It is provided for each. Generally, image data relating to a picture or the like has a large capacity because it is an aggregate of a large number of data. The image data storage unit performs data processing at night or the like when the apparatus is not operating, and stores various processing data so that the waiting time required for processing large-capacity image data as a whole printing apparatus can be minimized. It is provided for the purpose of reducing.

The fixing portion is a portion for fixing the ink such as a picture drawn on the print medium (cloth C) by washing or the like so as to withstand washing. In the printing apparatus 1 configured as described above, a printed product is manufactured by the procedure described below. First, in the introducing section 2, as shown in FIG. 1, the cloth C contained in the box 2a is introduced into a predetermined position of the conveying section 3 while at least wrinkling and centering are performed by a plurality of rolls 2b.

In the conveying section 3, the cloth C introduced from the introducing section 2 is pressed against the conveying belt 3b by the pressing roll 3e to be attached thereto, and is continuously conveyed to the printing section 4 side by the conveying belt 3b. At this time, the adhesive is applied to the transport belt 3b by a plurality of adhesive application rolls 3c. For this reason, since the cloth C is adhered to the conveyor belt 3b and conveyed in a stretched state, even if the cloth C is a highly elastic cloth, the cloth C is stuck to the conveyor belt 3b in a uniform tension state. In addition, there is no possibility of peeling from the conveyor belt 3b or distortion of a printed picture or the like.

In the printing section 4, ink droplets based on predetermined color data are colored from the respective line heads 40 which are arranged to face the cloth C which is continuously conveyed and which is wider than the width of the cloth C and is orthogonal to the conveyance direction. Separately applied, the edited pattern, character, etc. are drawn on the cloth C. Then, the printed fabric C is peeled off from the conveyor belt 3b on the downstream side of the printing unit 4 by the tension applied from the tension roll 5a, is preliminarily dried in the predrying unit 5, and then passes through the drying unit 6 to receive the ink. Is transported to the fixing section, and becomes a print product. Here, the position where the cloth C is peeled off from the conveyor belt 3b can be arbitrarily changed to the upstream side or the downstream side in the conveying direction in FIG. 1 by the tension applied from the tension roll 5a. Configuration of Line Head The line head 40 is based on the continuous ink jet system as described above, and includes the head portion 41, the electrode portion 42, the cap portion 45, and the wipe portion 46 (see FIGS. 5 and 6).
), And the cap portion 45 and the wipe portion 46.
Thus, a maintenance unit that prevents nozzle clogging due to ink drying is configured.

In the conventional printing apparatus, the print medium (cloth C) is intermittently transported in the transport direction, and the ink jet head is moved in the width direction of the print medium to draw a pattern or the like. On the other hand, unlike the conventional printing apparatus, the printing apparatus 1 of the present invention in which the printing unit 4 is arranged to have a width equal to or larger than the width of the cloth C continuously conveys the cloth C while the line heads 40 in each row in the fixed state are conveyed. Thus, it is possible to discharge ink droplets for each color to draw a pattern or the like, and it is possible to shorten the printing time.

The head portion 41 has an exciting means (piezoelectric vibrating element) for allocating ink supplied from an ink supply system, which will be described later, to a plurality of ejection nozzles and breaking the ejected ink column into ink droplets. The head section 41 is, for example,
Eight known nozzles 410 each having a discharge nozzle 410a and a piezoelectric vibrating element 410b are assembled into a head unit UH in units of eight (see FIG. 9). Head unit UH
Is a plurality of eight discharge nozzles 410a arranged linearly,
Twenty-five of these head units UH are lined up in a line and arranged so as to be wider than the width of the cloth C and orthogonal to the carrying direction.
Further, in the head portion 41, the gutter 47 is arranged below each deflection electrode, similarly to a known inkjet head. Further, in the head portion 41, a support member 41a is movably supported by guide shafts SH, SH vertically arranged on both sides of the conveyor belt 3b (FIG. 5 (a),
(C), FIG. 6 (a), (c) reference).

In the electrode portion 42, the charging electrode 43 is located at a position where the ink column ejected from each ejection nozzle 410a of the head unit UH is divided into ink droplets, and the width of the cloth C is downstream of the charging electrode 43 in the ink droplet flying direction. Deflection electrodes 44 for deflecting ink droplets in the respective directions are respectively arranged, and each electrode is configured in units of eight as in the nozzle (FIG. 7).
Through FIG. 9). Therefore, the deflection direction of the ink droplets is substantially perpendicular to the conveyance direction of the cloth C. As will be described later, in the electrode portion 42, a support member 42a is slidably supported by guide shafts SE, SE arranged above the conveyor belt 3b along the conveyance direction of the cloth C (FIG. 5).
(B), (d) and FIG. 6 (b), (d)).

The cap portion 45 has a main body 45a and a cap 45b that covers the entire lower portion of the head unit UH. The wipe portion 46 has a main body 46a and a wiper 46b made of a rubber blade or the like for wiping the surface of the ejection nozzle on the lower surface of the head unit UH. Where body 4
5a and the main body 46a are slidably supported by guide shafts SC, SC and guide shafts SW, SW arranged in parallel with the guide shafts SE, SE (FIGS. 5 (b), (d) and FIG. 6). (See (b) and (d)).

The structure of the line head 40 will be described below in more detail with reference to FIGS. 7 to 15. As shown in FIGS. 7 and 8, the line head 40 includes a head portion 41, an electrode portion 42, a cap portion 45, a wipe portion 46, and a gutter 47.
The ink collecting means 48 and the ink collecting means 48 are integrally housed in a housing (not shown), and the discharge nozzle 41 of each head unit UH is provided.
The ink droplets ejected from 0a are ejected toward the cloth C from below.

FIG. 7 is a side view of the line head 40 as seen from the pull-out direction. The arrow attached to the lower portion of the cloth C indicates the conveying direction of the cloth C, and the other arrows indicate the arrow. The moving directions of the members are shown. At this time,
Although not clear from FIG. 7, the head portion 41, the gutter 47, and the ink collecting means 48 can move apart from the electrode portion 42 (see FIG. 10). 8 is a front view of the line head 40 seen from the conveyance direction of the cloth C, and the cloth C is conveyed from the front side to the back side of FIG.

The head portion 41 has a supporting member 41a, a fixed plate 41b, a mounting plate 41c and a head unit UH. The supporting member 41a and the mounting plate 41c are fixed to the fixed plate 41b, and a plurality of mounting plates 41c are mounted on the mounting plate 41c. The head unit UH is attached. As shown in FIG. 9, the head unit UH includes eight nozzles 410 having ejection nozzles 410a and piezoelectric vibrating elements 410b and an ink supply system SKI described later.
It has an ink chamber 411 in which the ink supplied from is stored. In the head unit UH, each piezoelectric vibrating element 410b is controlled with high accuracy so that the volume difference of each ejected ink droplet is within ± 5%, preferably within 3% between the adjacent ejection nozzles 410a. ing.
Further, each head unit UH can be individually removed and replaced even after being assembled and arranged as the line head 40.

Here, as shown in FIG. 9, the discharge nozzle
The ink droplet DIK ejected from 410a is charged by the charging electrode 43 and then deflected by the deflection electrode 44 to be attached to the cloth C. The electrode part 42 includes a charging electrode 43 and a deflection electrode 44, and as shown in FIG. 7, the substrate 43a of the charging electrode 43 and the deflection electrode 44 are fixed to a fixed plate 42b.

The charging electrode 43 is an electrode for applying a charge to the ink droplets ejected from each ejection nozzle 410a of the head unit UH, and as shown in FIGS. 8 and 9, the same number is provided below the plurality of ejection nozzles 410a. It is arranged. Charging electrode 43
Is formed by laminating a plurality of copper foil patterns 43b to be electrodes on a substrate 43a made of electrically insulating synthetic resin (see FIG. 7), and is integrally formed for each head unit UH. Each copper foil pattern 43b is a head unit U
The charging electrode 43 is formed in a U-shape in plan view so that the charging electrode 43 can be maintained even when ink is ejected from each H ejection nozzle 410a.

The deflection electrode 44 is an electrode for deflecting the ink droplets charged by the charging electrode 43. As shown in FIGS. 8 and 9, the deflection electrode 44 has a plurality of electrode pairs and is arranged below the charging electrode 43. There is. Further, the charging electrode 43 and the deflection electrode 44 are attached to the same fixed member. The deflection electrode 44 is provided at a position corresponding to each discharge nozzle 410a at the ground side electrode 4
4a and the high voltage side electrode 44b are arranged, and one electrode is shared with the electrode of the adjacent discharge nozzle 410a. An insulating cover 49 is detachably attached to the lower portion of the deflection electrode 44.

The insulating cover 49 prevents a short circuit caused by the ink mist adhering to the deflection electrode 44 and the lower portion of the fixing plate 41b of the head portion 41. That is, the ink droplets ejected from the respective ejection nozzles 410a of the head unit UH are collected by the gutter 47
When it collides with, part of it becomes ink mist and scatters,
It adheres to the deflection electrode 44 in the vicinity. Therefore, the deflection electrode 4
By attaching an insulating cover 49 to the lower part of 4,
Ink mist is prevented from adhering to the deflection electrode 44, and the ground side electrode 44a and the high voltage side electrode 44 caused by the ink mist are prevented.
The short circuit with b is prevented.

As shown in FIG. 7, the cap portion 45 is disposed above the wipe portion 46 in the vicinity of the downstream side of the head portion 41 as seen from the conveyance direction of the cloth C so as to be movable in the direction indicated by the arrow. . In the cap portion 45, as shown by the arrow in the figure, the main body 45a moves forward or backward along the conveyance direction of the cloth C, and in the cap position described later,
As shown in FIG. 2, the cap 45b is put on the entire lower part of the head unit UH. As shown in FIGS. 12 and 13, the cap 45b has an ink reservoir HIK formed by inclining the bottom surface, and a seal 45c having a triangular cross section is attached to the peripheral edge thereof. Therefore, the cap 45b is the seal 45
Since c contacts the lower part of the head unit UH at the apex of the triangle, a reliable seal can be achieved with a low load. Further, the line head 40 is raised above a predetermined cap position, and after the cap 45b moves to the lower part of the head unit UH, the line head 40 is moved to the predetermined cap position to ensure a high degree of sealing. Various seals are possible.

As shown in FIG. 7, the wipe portion 46 is disposed below the cap portion 45 near the downstream side of the head portion 41 when viewed from the conveyance direction of the cloth C so as to be movable in a direction indicated by an arrow. There is. In the wipe portion 46, as shown by the arrow in the figure, the main body 46a moves forward or backward along the conveyance direction of the cloth C, and in the wipe position described later, as shown in FIG.
As shown in, the wiper 46b wipes the surface of the ejection nozzle on the lower surface of the head unit UH. Therefore, as shown in FIG. 14, the wiper 46b is set to have a length equal to or larger than the width of the cloth C so that all the head units UH can be wiped at once.

The gutter 47 is a means for collecting ink droplets that have not been used for printing, and is provided for each electrode pair of the deflection electrodes 44. As shown in FIG. 11, the gutter 47 includes a collecting unit 47 a that collects ink droplets, and a collecting unit 47 a.
And a slit-shaped flow path 47c for guiding the ink collected in to the round groove 47b. The gutter 47 keeps the same position with respect to the corresponding discharge nozzle 410a of the head unit UH, as shown in FIG.
7a is attached to the fixing plate 41b of the head portion 41 on the side of the round groove 47b so that the tip side of the 7a becomes higher. At this time, by attaching the gutter 47 to the fixed plate 41b,
It has the same potential as the ground-side electrode 44a of the deflection electrode 44.
Therefore, the gutter 47 corresponds to the high voltage side electrode 44 of the deflection electrode 44.
In order to prevent a short circuit with b, it is arranged below the ground side electrode 44a.

The ink collecting means 48 is attached to the lower portion of the fixed plate 41b of the head portion 41 and is arranged below the gutter 47 to have a width equal to or larger than the width of the cloth C. The ink collecting means 48 is collected by each gutter 47 and is rounded by the flow passage 47c. Is guided to and collects the dropped ink. The ink collecting means 48 is a collecting gutter 48.
a, the support member 48b, and the recovery gutter 48a are supported by the support member 48b.
Along with this, it has a linear bush 48c that moves along the conveyance direction of the cloth C. The collection gutter 48a is provided with a collection port (not shown) on one side in the width direction, the collection port side is arranged low, and the collection ink is sucked and collected from the collection port by a suction unit (not shown). Here, the recovery port is arranged at a position and orientation that does not spatially intersect with the flight path of the ink droplet. Further, the collection gutter 48a is arranged at the position shown in FIG. 7 during the print standby (when the deflection power supply is turned off and the non-deflected ink is collected), and is illustrated so as not to collect ink droplets during printing. It is moved to the right in the figure by the drive means and the linear bush 48c.

The line head 40, as shown in FIG.
The rails 1a, 1a provided on the printing apparatus 1 are suspended so as to be able to be pulled out in the direction shown by the arrow. Therefore,
Each of the line heads 40 can be individually pulled out or replaced with ink used for maintenance of the printing unit 4. Also, when exchanging the conveyor belt 3b,
It is possible to work with all line heads 40 pulled out. At this time, the position reproducibility of the state where each line head 40 is returned to the original position is sufficiently considered.

Further, in the line head 40, since the temperature of the ink affects the stability of a drawn pattern or the like, the air whose temperature and humidity are controlled by an air conditioner installed outside is supplied from one inlet. It is configured to be discharged from the other outlet in the pull-out direction. At this time, the air sets the flow velocity of the ink droplet in the flight path to 20 cm / sec or less.

Further, since the line head 40 prints various kinds of cloth, the distance between the cloth and the cloth, that is, the height can be adjusted according to the thickness of the cloth to be printed, as shown in FIG. As shown in FIG.
The spacer 1c is arranged as an adjusting means between the and, and the spacer 1c is replaced with one having a different thickness according to the thickness of the cloth. In this case, an air cylinder can be used instead of the spacer 1c. Ink supply system SIK shown in the ink supply system 4 is a supply system for supplying ink for color-coded to each line head 40, the ink tank TIK,
A portion including a gear pump PG, filters FM and FLC, a heat exchanger HEX, and the like, and a portion indicated by a dotted line in FIG.

In the ink supply system SIK, the ink in the ink tank TIK is supplied to the line head 40 by the gear pump PG.
Although the pressure is sent to each of the discharge nozzles, dusts and the like in the ink that cause the discharge nozzles to be clogged or the ink discharge direction to be disturbed are removed by the filters FM and FLC. Ink is supplied to the ink tank TIK from the outside. At this time, in the continuous-type inkjet printing apparatus, the stability of the ejection amount of the ink ejected from the ejection nozzles is most related to the stability of the entire apparatus. Therefore, in the printing apparatus 1 of the present invention, it is necessary to control so that the flow rate of the ink ejected from the ejection nozzle is kept constant.

However, in the continuous type ink jet system, since the ink flow rate is small, it is difficult to measure accurately by an inexpensive means. Therefore, in the printing apparatus of the present invention, the ink supply system S
The ink supply pressure in IK is controlled by the gear pump PG, and the ink temperature and hence the viscosity are controlled. Specifically, a thermometer (not shown) is attached to the ink supply system SIK, and the heat exchanger HEX heats or cools the ink so that the ink has a predetermined viscosity based on the measured ink temperature.

Depending on the pattern drawn on the cloth C, so-called CYMK (cyan, yellow, magenta, black)
It is necessary to use fluorescent colors that cannot be reproduced in. Therefore, when the fluorescent color is used, a cleaning liquid is supplied from the outside to clean the ink supply system SIK as shown in the figure. In this case, the ink supply system SIK of each line head 40 is as shown in FIG.
As shown in, a plurality of ink tanks TIK and a plurality of cleaning liquid tanks TWL are provided so that the ink can be replaced in a short time. Line Head Operation In the printing apparatus 1, each line head 4
0, the head section 41, the electrode section 42, the cap section 4
5 and the wipe part 46 are variously positioned according to the printing state as follows. Here, in the printing apparatus 1, inks of different colors are ejected from the eight line heads 40 to draw a predetermined design or the like designed in advance, but the operation in each line head 40 is the same. For simplicity, a single line head 40 will be described.

First, the printing apparatus 1 is turned on by switching on.
In the standby position shown in FIGS. 5 (a) and 5 (b), the head portion 41 of the line head 40 moves downward and the supporting member 42a of the electrode portion 42, The main body 45a of the cap portion 45 and the main body 46a of the wipe portion 46 are moved to the standby position side which is the downstream side of the head portion 41 of each guide shaft SE, SC, SW in the transport direction of the cloth C. At this time, in the head portion 41, ink is continuously ejected from a large number of ejection nozzles.

5 (a) and 5 (c) are front views of the line head 40 seen from the conveyance direction of the cloth C, FIG.
6B and 6D are side views of the line head 40 seen from the pull-out direction, and the arrows indicate the conveyance direction of the cloth C, which is the same in FIG. Next, at the wipe position, as shown in FIGS. 5C and 5D, after the support member 41a of the head portion 41 moves to the wipe position along the slide shafts SH and SH, the wipe portion 46 is moved.
The main body 46a moves forward along the slide shafts SW, SW. As a result, as shown in FIG. 15, the wiper 46b moves to wipe the ink from the surface of the ejection nozzles of the head unit UH, and corrects the deviation of the ejection direction due to the ink adhering to the surface. At this time, the electrode portion 42 and the cap portion 45 are moving to the standby position side, as shown in FIG.

Next, at the print position,
As shown in FIGS. 6A and 6B, after the wipe portion 46 moves to the standby position side, the head portion 41 descends to the print position, and the electrode portion 42 advances to the position just below the head portion 41. Then, based on the image data stored in the image data storage unit in advance, the electrode unit 42 controls the flight direction of the ink droplets ejected from the large number of ejection nozzles of the head unit 41, and a predetermined pattern is formed on the cloth C. draw. At this time, it is needless to say that the head portion 41 and the electrode portion 42 are positioned with high precision in order to obtain a printed product of excellent quality in which the color tone and texture are reproduced more accurately.

In this way, when the drawing on the cloth C is completed, the cap position shown in FIGS. 6 (c) and 6 (d) is switched to, and the electrode portion 42 is moved to the standby position side.
The head portion 41 moves up. And each head unit U
As shown in FIG. 12, H is covered by the cap 45b of the cap portion 45 whose entire lower portion has advanced. Thereby, in the head section 41, clogging of each ejection nozzle due to drying of the ink when printing is stopped, which is the biggest problem of the inkjet head, is eliminated. Stable operation of the line head In order to consistently and stably produce a high-quality printed product in the printing apparatus 1, the ink droplets ejected from the line head 40 adhere to a target position on the cloth C (print medium). Need to be controlled.

As can be imagined from the principle, the ink jet system has the following problems. That is: 1. When the direction of ink ejection from the ejection nozzle changes, the drawing range of the ejection nozzle shifts. 2. If the ejection speed of the ink at the ejection nozzle changes, the cutting phase of the ink droplet at which the ejected ink is cut into ink droplets changes.

3. When the ejection speed of the ink in the ejection nozzle changes, the drawing width of the ejection nozzle changes. For this reason, as described above, the filters FM and FLC for removing dusts and the like in the ink that cause the ejection nozzles of the line head 40 to be clogged or the ink ejection direction to be misaligned are arranged in the ink supply system SIK. . Further, in the ink supply system SIK, as described above, the ink supply pressure is controlled by the gear pump PG so that the ink ejection speed does not change.
In addition to highly accurate control, the ink temperature and viscosity are controlled to control the ink discharge flow rate, that is, the droplet velocity of ink droplets to a constant target velocity.

However, in spite of performing the control as described above, in the line head 40, when the ink ejection is once stopped and the ink ejection is restarted, the ejection nozzles slightly The ink ejection direction changes. In addition, depending on the type of ink, the ejection direction generally changes little by little due to the formation of a small lump of ink near the outlet of the ejection nozzle.

For this reason, in the printing apparatus 1, the ink ejection state is observed at the start of operation and every time a fixed time elapses, and feedback control is performed so that the ink droplets are automatically adjusted so as to adhere to appropriate positions. . In this automatic adjustment, a test pattern is drawn on the film by each line head 40, the test pattern is read by a CCD camera, image processing is performed, and the operation of each line head 40 is fed back using the image processed information as various control information. It is controlled. Flow of image data The image data relating to a picture or the like created by the data creating / editing unit is decomposed into image data of a predetermined color for each line head 40 by the color adjusting unit and divided into image data for each ejection nozzle. After that, the image data is stored in the image data storage unit provided in each discharge nozzle.

At the time of drawing on the cloth C, a pattern or the like is drawn by the ink droplets ejected from the ejection nozzles based on the image data stored in each image data storage section. At this time, if the image data stored in each image data storage unit is repeatedly used, it is possible to create the cloth C in which the same pattern is repeatedly drawn. The color matching printing apparatus 1 draws a pattern or the like on the cloth C while discharging ink for each color by eight line heads 40 arranged at a predetermined pitch, for example, a pitch of 1,000 mm. Therefore, in the printing apparatus 1, the distance between the first line head 40 and the last line head 40 is as large as 7,000 mm.
Therefore, in the printing apparatus 1, when the transport amount of the fabric C by the transport belt 3b is unstable and fluctuates, a color shift occurs in a drawn pattern or the like, and the quality as a print product is deteriorated.

As a means for preventing such color misregistration, usually, the moving amount of the conveying belt 3b, that is, the conveying amount is detected by a detecting unit such as an encoder at predetermined time intervals, and the variation amount of the conveying amount is counted. The method is general. However, the elongation of the conveyor belt 3b and the first and last line heads 40
Is too large, it is difficult to improve the accuracy of color matching using a detection means such as an encoder.

Therefore, in the printing apparatus 1, in order to perform highly accurate color matching, the line head 4 which is the most upstream in the transport direction is used.
When 0, print a predetermined mark on the cloth C at a predetermined pitch,
These marks are detected as mark signals by detecting means provided on each of the other line heads 40 arranged downstream.
The printing apparatus 1 achieves high-accuracy color matching by operating the delay circuit based on the detected mark signal and controlling the amount of the cloth C conveyed by the conveying belt 3b.

In the above embodiment, the case where the ink jet system is the continuous type has been described, but it goes without saying that the present invention can also be used in the on-demand type ink jet system.

[0056]

As is apparent from the above description, according to the present invention, it is possible to provide a printing apparatus which can maintain the performance of a large number of ejection nozzles for a long period of time and is excellent in maintainability. At this time, according to the printing apparatus of the second aspect, since the print medium is provided with the carrying means for carrying the print medium in the horizontal direction, if the print medium alone is carried with a large number of ejection nozzles fixed, the printing time is shortened. It can be shortened.

According to the printing apparatus of the third aspect, the guide means moves the plurality of discharge nozzles in the vertical direction,
Further, according to the printing device of the seventh and the eighth aspects, since the first and second guide members for guiding the wipe operation and the cap operation along the transport direction of the print medium are provided,
It is possible to avoid interfering with a plurality of discharge nozzles in each operation.

According to the fourth aspect of the present invention, since the position where the cap operation is performed is the third position which is different from the position where the wipe operation is performed in the second position, the wipe operation and the cap operation are performed. It is possible to avoid the confusion as a separate operation. According to the printing apparatus of claim 5, since the wiper is arranged along the arrangement direction of the plurality of ejection nozzles and has a length equal to or larger than the width of the print medium, the print medium may be wide. Even a narrow print medium can be used, and the degree of freedom in use of the print medium used can be increased.

According to the printing apparatus of the sixth aspect, since the cap means has a sealing member having a triangular cross section, when the nozzle surface is covered, it is possible to reliably seal even with a low load. You can According to a seventh aspect of the present invention, there is provided a first guide member that is arranged in parallel with the conveyance direction of the print medium and that guides the wiping operation of the wiping means along the conveyance direction. According to this printing apparatus, since it is provided with the second guide member which is arranged in parallel with the conveying direction of the print medium and guides the cap operation of the cap means along the conveying direction, the wiping means and the cap means It is possible to smoothly guide the respective operations of the wipe and the cap.

According to the printing apparatus of the ninth aspect, the first position contacts a part of the structure for carrying the print medium and a part of the head section having the plurality of ejection nozzles. Since the head is moved to the wipe position and the cap position, it is possible to return to the print position with high position reproducibility.

According to the printing apparatus of the tenth aspect, since the plurality of ejection nozzles are provided with adjusting means for adjusting the position in the thickness direction according to the thickness of the print medium,
Either thin or thick print media can be accommodated. According to the printing apparatus of claim 11, the plurality of ejection nozzles are assembled into a head unit in which a predetermined number of the ejection nozzles are linearly arranged on the same plane, and are made orthogonal to the transport direction of the print medium. Since a plurality of units are arranged over the width, it is possible to print on a print medium for each color.

According to the printing apparatus of the twelfth aspect, since each of the head units is provided with the rail for pulling out in the direction orthogonal to the conveying direction of the print medium, even when a plurality of head unit rows are provided. A work space can be secured by pulling out each row for maintenance, and maintainability is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a printing apparatus of the present invention.

FIG. 2 is a perspective view illustrating a drawing mechanism of a line head of the printing apparatus of FIG.

3 is a side view showing an adjusting unit of a line head in the printing apparatus of FIG.

FIG. 4 is a configuration diagram of an ink supply system in the printing apparatus of FIG.

FIG. 5 is a view showing the line head 4 in the printing apparatus of FIG.
FIG. 8 is an operation diagram showing the operation of the head portion, the electrode portion, the cap portion, and the wipe portion at the 0 standby position and the wiping position.

FIG. 6 is a head portion, an electrode portion, and a line head 40 at a print position and a cap position.
FIG. 9 is an operation diagram showing the operation of the cap portion and the wipe portion.

FIG. 7 is a side view of the line head in the printing apparatus of FIG. 1 viewed from the side in the print medium transport direction.

FIG. 8 is a front view of the line head of FIG. 7 viewed from the print medium conveyance direction.

9 is a front view of the line head viewed in units of one head unit in FIG. 7. FIG.

10 is a side view of the line head of FIG. 7 when the power supply unit is removed.

11 is a perspective view of a gutter in the line head of FIG.

FIG. 12 is a front view showing a state in which the head unit is covered with a cap of a cap portion in the line head of FIG. 7.

13 is a perspective view of a cap in the head unit of FIG.

FIG. 14 is a front view showing a state in which a wipe part is moved to a plurality of head units.

FIG. 15 is a side view showing a state in which the head unit of FIG. 14 is wiped with a wiper of a wipe portion.

FIG. 16 is a configuration diagram of an ink supply system of each line head provided with a plurality of ink tanks TIK and cleaning liquid tanks TWL.

[Explanation of symbols]

 1 Printing Device 1c Spacer (Adjusting Means) 2 Introductory Section 2a Box 3 Conveying Section 3a Roll 3b Conveying Belt 3c Coating Roll 3d Brush Roll 3e Pressing Roll 4 Printing Section 5 Pre-Drying Section 5a Tension Roll 6 Drying Section 7 Shaking Off Section 40 Lines Head 41 Head portion 42 Electrode portion 43 Charging electrode 44 Deflection electrode 45 Cap portion 45b Cap 46 Wiping portion 46b Wiper 47 Gutter 47a Collection portion 47c Flow path 48 Ink collection means 48a Recovery trough 48c Linear bush 49 Insulation cover 410 Nozzle 410a Discharge nozzle 410b Piezoelectric vibration element 411 Ink chamber C cloth (print medium) FM, FLC filter HEX heat exchanger PG gear pump SIK ink supply system TIK ink tank TWL cleaning liquid tank UH head unit

Claims (12)

[Claims] 1. A printing apparatus for printing a print medium with ink droplets ejected from a plurality of ink jet type ejection nozzles, which guides the movement of the plurality of ejection nozzles to first and second positions. A guide means for fixing is provided, the first position is a position for printing on the print medium, and the second position is a position for performing a wiping operation of wiping the nozzle surfaces of the plurality of ejection nozzles with a wiping means. Characteristic printing device. 2. The printing apparatus according to claim 1, further comprising a transport unit that transports the print medium in a horizontal direction. 3. The printing apparatus according to claim 1, wherein the guide unit moves the plurality of ejection nozzles in a vertical direction. 4. A cap means for covering the nozzle surface is provided, and a position at which the cap operation is performed is a third position different from a position at which the wipe operation is performed at the second position. Printing device. 5. The printing apparatus according to claim 1, wherein the wipe unit is arranged along the arrangement direction of the plurality of ejection nozzles and has a length equal to or larger than the width of the print medium. 6. The printing apparatus according to claim 1, wherein the cap unit has a seal member having a triangular cross section. 7. The print according to claim 1, further comprising a first guide member which is arranged in parallel with a transport direction of the print medium and which guides a wiping operation of the wipe means along the transport direction. apparatus. 8. A second guide member, which is arranged in parallel with the transport direction of the print medium, and which guides the cap operation of the cap means along the transport direction.
7 to any one of the printing apparatuses. 9. The first position is positioned by bringing a part of a structure for carrying the print medium into contact with a part of a head portion having the plurality of ejection nozzles. A printing device according to any one of 1 to 8. 10. The printing apparatus according to claim 1, wherein each of the plurality of ejection nozzles includes an adjusting unit that adjusts a position in a thickness direction according to a thickness of the print medium. 11. The plurality of discharge nozzles are assembled into a head unit in which a predetermined number of discharge nozzles are linearly arranged on the same plane, and a plurality of units are formed in a width equal to or larger than a width in a direction orthogonal to the transport direction of the print medium. The printing device according to any one of claims 1 to 10, which is arranged. 12. The printing apparatus according to claim 11, further comprising a rail that pulls out each of the head units in a direction orthogonal to a transport direction of the print medium.