JP5278822B2 - Line-type inkjet printer - Google Patents

Description

  The present invention relates to a line type ink jet printing apparatus having an ink jet head in which a plurality of nozzles are arranged in a width direction perpendicular to a feeding direction of a printing medium.

  The inkjet printing apparatus that ejects ink droplets from the nozzles of the inkjet head that is brought close to the printing surface of the substrate to be fed is a serial type that prints while scanning the inkjet head in the width direction of the printing surface; There is a line type that prints by fixing an inkjet head in which a plurality of nozzles are arranged in the width direction of the printing surface (see, for example, Patent Documents 1 and 2). The line type can be printed at a high speed at a higher speed than the serial type, and is therefore often used in relatively large industrial printing apparatuses.

  The inkjet head of the line-type inkjet printing apparatus is formed by integrally forming a plurality of nozzles arranged over the entire width of the printing surface, or by combining a plurality of head units having a plurality of nozzles arranged in the width direction. Is integrated. In the device described in Patent Document 2, the integrated inkjet heads are arranged in a plurality of rows in the feeding direction of the printing medium, and these inkjet heads can be moved to a maintenance area provided on one end side in the width direction. .

Japanese Patent Laid-Open No. 11-334047 Japanese Patent Laid-Open No. 2005-199658

  The conventional line-type inkjet printing apparatus described in Patent Documents 1 and 2 integrates an inkjet head in which a large number of nozzles are arranged. However, since it is close to the printing surface, there is a problem that nozzles are likely to be clogged by drying due to an air flow caused by the fed printing material. As the feeding speed of the printing medium increases, nozzle clogging due to drying tends to occur.

  Also, in a printing apparatus that often performs printing partially in the width direction of the printing surface, the nozzles are always arranged over the entire width of the printing surface, which increases the number of wasted nozzles. .

  Furthermore, even if the integrated inkjet head can be retracted to the maintenance area at the time of maintenance as described in Patent Document 2, it is necessary to retract all nozzles when some nozzles have a problem. There is also a problem of poor maintenance efficiency.

  Accordingly, an object of the present invention is to provide a line-type inkjet printing apparatus in which unused nozzles are not dried, necessary nozzles can be arranged in the width direction of the printing surface without waste, and the maintenance efficiency is excellent.

  In order to solve the above-described problems, the present invention has a plurality of nozzles arranged in the width direction of the printing surface perpendicular to the feeding direction of the printing material, in proximity to the printing surface of the printing material to be fed. In a line-type ink jet printing apparatus provided with an ink jet head, the ink jet head in which the nozzles are arranged is divided into a plurality of head units in the width direction of the printing surface, and these divided head units are divided in the width direction of the printing surface. And a width direction moving means for individually moving the head unit guided by the guide rail in the width direction.

  That is, the inkjet head in which the nozzles are arranged is divided into a plurality of head units in the width direction of the printing surface, and the divided head units are guided by the guide rail in the width direction of the printing surface and the guide rails. By providing a width direction moving means for individually moving the head unit in the width direction, the divided head units are individually moved to the position in the width direction that requires printing on the printing surface, and the unused nozzles are dried. The necessary nozzles can be arranged in the width direction of the printing surface without waste, and the maintenance efficiency is excellent.

  By providing the guide rails in a plurality of rows at intervals in the feeding direction of the printing medium, and providing a row transition means for shifting the individually moved head units to another row of guide rails, Various print patterns can be handled by changing the number of head units arranged in each row.

  The row shifting means is provided with a dividing portion at the same position in the width direction in at least one location of each of the plurality of rows of guide rails, and the division portion can be shifted between the rows of guide rails. The head unit moved to the position can be transferred to another row of guide rails.

  By providing the width direction moving means for each of the plurality of rows of guide rails, the head units can be thinned out and inserted, and the head units can be arranged on the guide rails efficiently.

  By making the width direction moving means a linear motor that individually drives the head unit in the width direction, the head unit can be positioned in the width direction with high accuracy.

  By providing the guide rail with a retraction area that extends to the outside in the width direction of the printing surface and retreats the head unit from the printing surface, the head unit including the nozzle can be easily maintained and replaced.

  The line-type inkjet printing apparatus of the present invention divides an inkjet head in which nozzles are arranged into a plurality of head units in the width direction of the printing surface, and guide rails that guide these divided head units in the width direction of the printing surface. Since the width direction moving means for individually moving the head unit guided by the guide rail in the width direction is provided, the divided head unit is individually moved to the position in the width direction where printing on the printing surface is required. Thus, the unused nozzles do not dry, the necessary nozzles can be arranged in the width direction of the printing surface without waste, and the maintenance efficiency can be improved.

Schematic plan view showing an embodiment of a line-type inkjet printing apparatus Schematic front view of FIG. Bottom view of the head unit of FIG. a and b are bottom views showing modifications of the head unit of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the line-type inkjet printing apparatus is fed at a high speed of 50 m / min or more by the conveyor belt 21, and prints on the upper printing surface of the cardboard sheet A having a width of 1 m or more. The two guide rails 1a and 1b are provided on the upper surface side of the corrugated cardboard sheet A to be fed, in the width direction perpendicular to the feeding direction, at intervals in the feeding direction. 1b, a plurality of head units 3 of an inkjet head in which nozzles 2 close to the printing surface are arranged on the lower surface are arranged via a base 4 which is a mover of a linear motor having guide rails 1a and 1b as stators. , Are arranged to be movable in the width direction. Therefore, each head unit 3 can be individually and accurately moved to the position in the width direction where printing on the printing surface is required.

  Each of the guide rails 1a and 1b is extended at one end side to the outside of the printing surface, and a divided portion 5 is provided at the same position in the width direction of the extended portion, and these divided portions 5 are perpendicular to the respective guide rails 1a and 1b. It is installed on a shift stand 6 that shifts in both directions. The shift table 6 is also provided with a preliminary division unit 5a at an interval equal to the interval between the division units 5, and when the shift table 6 is shifted, any of the division units 5 or the preliminary division unit 5a is provided with each guide. It is connected to the rails 1a and 1b in a straight line. Therefore, as indicated by the alternate long and short dash line in FIG. 1, the desired head unit 3a disposed on the guide rail 1a and the head unit 3b located at the end of the guide rail 1a are moved to the extension portion side to thereby obtain the desired head unit 3a. Is positioned in the dividing portion 5 and the shift base 6 is shifted in one direction, whereby the head unit 3a can be shifted to another guide rail 1b.

  Further, one guide rail 1b extends further to the outside than the other guide rail 1a, and an extension portion of the guide rail 1b is a retreat area 7. Accordingly, as indicated by a two-dot chain line in FIG. 1, the head unit 3c in which a problem has occurred can be moved to the retreat area 7 and maintenance and replacement can be easily performed. By using the shift table 6, the head unit 3 c can be moved from the other guide rail 1 a to the retreat area 7.

  The operation of the nozzle 2 of each head unit 3 and the driving of each pedestal 4 by a linear motor are performed by a wireless or wired system, and these control signals are sent from a controller (not shown) according to image data to be printed. Is sent. In the case of performing the wired method, it is preferable that connectors are attached to a plurality of signal cables having a margin in length, and these connectors can be attached to and detached from each head unit 3 or base 4 with one touch. The shift table 6 is also driven by a wireless or wired system.

  Each of the plurality of head units 3 has the same length in the width direction of the printing surface and is formed to be shorter than the length of the dividing portion 5 of the guide rails 1a and 1b. A plurality of nozzles 2 are arranged in two rows in the width direction. The number of nozzles 2 may be one or three or more. Accordingly, the head units 3 are compatible as long as the ink colors are the same, and can be freely moved between the two guide rails 1 a and 1 b by the shift base 6.

  4A and 4B show modifications of the head unit 3, respectively. The modified example of FIG. 4 (a) is an obliquely inclined end surface in the width direction and the cross section is a parallelogram. The modified example of FIG. 4 (b) protrudes alternately on the left and right end surfaces in the width direction. A step is added. In each of these modifications, two rows of nozzles 2 are arranged on the left and right sides from the center, and as shown by the alternate long and short dash line in each figure, when the end face of the adjacent head unit 3 is abutted. The nozzles 2 are arranged at equal intervals even at the boundary between the head units 3 by the respective front and rear nozzle rows. In the case of the head unit 3 shown in FIG. 3, the boundary between the head units 3 can be obtained by arranging the adjacent ones in the width direction so that the end portions in the width direction are wrapped around the respective guide rails 1a and 1b. The nozzles 2 can be arranged at equal intervals in the section.

  Although not shown, each head unit 3 described above is equipped with a cartridge-type or fixed-type ink tank. When the head unit 3 is moved to the retreat area 7, the cartridge-type tank is replaced or fixed. Ink is supplied to the tank. Therefore, it is not necessary to connect an ink tube for supplying ink to each head unit 3, and the head unit 3 can be easily moved or moved between the rows.

  In the embodiment described above, the guide rail of the head unit is two, but the guide rail can be three or more. In addition, when a division part and a shift stand are not provided, it is good also as one guide rail.

  Further, in the above-described embodiment, the dividing portion of each guide rail is provided at one place in the width direction of the printing surface, and the retreat area extending only on one guide rail is provided, but the dividing portion is provided at two or more places in the width direction. The evacuation area can also be provided in each guide rail.

1a, 1b Guide rail 2 Nozzle 3, 3a, 3b, 3c Head unit 4 Base 5, 5a Dividing part 6 Shift base 7 Retraction area 21 Conveying belt

Claims (5)

In a line-type inkjet printing apparatus in which an inkjet head in which a plurality of nozzles are arranged in the width direction of a printing surface perpendicular to the feeding direction of the printing material is disposed close to the printing surface of the printing material to be fed. The inkjet head in which the nozzles are arranged is divided into a plurality of head units in the width direction of the printing surface, and the divided head units are guided in the width direction of the printing surface, and are guided by the guide rails. Width direction moving means for individually moving the head units in the width direction, the guide rails being provided in a plurality of rows at intervals in the feeding direction of the printing medium, and the head units that are individually moved A line type ink jet printing apparatus, characterized in that it is provided with a row shifting means for shifting to another row of guide rails . The row shifting means is provided with a dividing portion at the same position in the width direction in at least one location of each of the plurality of rows of guide rails, and the division portion can be shifted between the rows of guide rails. The line-type ink jet printing apparatus according to claim 1 , wherein the head unit moved to a position is moved to a guide rail in another row. The line-type inkjet printing apparatus according to claim 2 , wherein the width direction moving unit is provided for each of the plurality of guide rails. The line-type inkjet printing apparatus according to any one of claims 1 to 3 , wherein the width direction moving means is a linear motor that individually drives the head unit in the width direction. 5. The line-type inkjet printing apparatus according to claim 1 , wherein the guide rail includes a retreat area that extends to the outside in the width direction of the print surface and retreats the head unit from the print surface.

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