JPH04185452A - Color ink jet printer - Google Patents

Abstract

PURPOSE:To make two-way printing executable by a method wherein an ink jet head is turned in 180-degree arc in accordance with the direction of movement of the ink jet head in a printing in which ink is ejected from nozzles while the ink jet head is moved either in the forward or the rearward direction. CONSTITUTION:Nozzles 17 are arranged lengthwise and crosswise in matrix. While the nozzles move forward by spacing motion, ink in each color from the nozzles 17 for each color is ejected to the same part on a printing surface, being superimposed one another, by control signals inputted to a drive circuit from a printing control part 24. As the nozzles 17 for yellow ink are positioned in the forefront of the forward movement, color printing is made with the inks for yellow, magenta, cyan, and black superimposed one another in this order from the bottom to the surface. When the spacing motion is shifted to the rearward movement, an ink jet head 10 is turned instantaneously in 180-degree arc by operation of a head-turning motor 13 and is placed upside down. The color printing in the rearward movement is made, as in the case of the forward movement, with the inks for yellow, magenta, cyan, and black superimposed one another in this order from the bottom to the surface.

Description

[Detailed Description of the Invention] [Summary] To enable bidirectional printing and easily perform high-speed printing regarding an inkjet printer that performs color printing by sequentially discharging ink of multiple colors onto the same portion of the printing surface. The purpose of the present invention is to provide a color inkjet printer capable of discharging ink of different colors, including an inkjet head in which a plurality of nozzles for discharging ink of different colors are arranged side by side in the horizontal direction, and each of the nozzles while moving the inkjet head in the horizontal direction. A color inkjet printer having a head driving means for sequentially ejecting ink from the front to the same portion of a printing surface, wherein the head driving means causes the inkjet head to eject ink from the nozzle while moving the inkjet head back and forth; A head rotating means is provided for rotating the inkjet head by 180 degrees in response to the direction of movement of the inkjet head by the head driving means.

[Industrial application field]

The present invention relates to an inkjet printer that performs color printing by sequentially discharging ink of a plurality of colors onto the same portion of a printing surface.

Inkjet printers are used to perform high-speed, high-quality printing by ejecting ink from a nozzle toward the printing surface, but in recent years, color inkjet printers that print in color have also come into use.

[Conventional technology]

In a color inkjet printer, for example, nozzles for each color of yellow, magenta, cyan, and black are arranged horizontally on an inkjet head, and while the inkjet head is moved laterally, each nozzle prints on the same part of the printing surface. The ink is sequentially ejected to the inks.

Therefore, the ink layers of each color are overlapped on the printing surface in the order of yellow, magenta, cyan, and black from the bottom, thereby expressing a desired color on the printing surface.

[Problem to be solved by the invention]

In recent years, there has been an increasing need to increase the printing speed of printers, and for this purpose, it is effective to enable printing in both directions when the print head moves back and forth.

However, when bidirectional printing is performed in the conventional color inkjet printer as described above, the order of the color ink layers is reversed between "forward" and "return". In other words, in the above example, ``During reprinting, ink layers are formed in the order of black, cyan, magenta, and yellow from the bottom, and a color different from the color expressed by the color layers in the correct order is produced. It gets expressed.

Therefore, conventional color inkjet printers cannot print in both directions, making it difficult to increase the printing speed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color inkjet printer that can eliminate such conventional drawbacks, enable bidirectional printing, and easily perform high-speed printing.

[Means to solve the problem]

In order to achieve the above object, the color inkjet printer of the present invention includes an inkjet head 10 in which a plurality of nozzles 17 for ejecting ink of different colors are arranged in a horizontal direction, as shown in FIG. , a color inkjet printer having a head drive means 20 that sequentially ejects ink from each nozzle 17 onto the same portion of the printing surface while moving the inkjet head IO in the lateral direction, the head drive means 2
0, the inkjet head IO is caused to eject ink from the nozzle 17 while reciprocating, and the inkjet head IO is rotated by 180 degrees corresponding to the direction of movement of the rad IO toward the inkjet by the head driving means 20. It is characterized in that a head rotating means 13 for rotating the paper is provided.

In addition, in the inkjet head 10, a plurality of nozzles 17 for ejecting ink of the same color are arranged in a line in the vertical direction, and as a whole, a plurality of nozzles 17 are arranged in each of the vertical and horizontal directions. You can leave it there.

[Effect]

Since the inkjet head IO rotates 180 degrees in response to the reciprocating movement of the inkjet head 10,
When moving in either direction (backward or backward), ink of each color can be ejected to the same portion of the printing surface in the same order.

〔Example〕

Examples will be described with reference to the drawings.

Figure 2 shows an inkjet head printer.
In the figure, l is a platen roll around which printing paper (not shown) is wound, and is rotationally driven by a line feed motor 2.

A carriage 6 is supported by two stay shafts 4 and 5 arranged parallel to the axis of the platen roll l. A belt 8 driven by a space motor 7 is connected to the carriage 6, and rotation of the space motor 7 causes the carriage 6 to reciprocate along the stay shaft 4.5.

An inkjet head 10 is attached to the carriage 6 with its nozzle facing one side of the platen. The inkjet head 10 is rotatably supported by pongee receivers 11 and 12 at the front and rear thereof, and is driven to rotate in 180 degree increments by a head rotation motor 13 attached to the carriage 6, so as to assume an upright or inverted posture. .

The inkjet head 10 has yellow (Y), magenta (M
), cyan (C), and black (K). 14 is a group of contacts for transmitting an ink ejection operation control signal of the inkjet head 10 from the carriage 6 side to the inkjet head 10 side.

A main control unit 21 receives control signals from the host device and performs overall operational control of the printer. 22 is a line feed control unit for controlling the operation of the line feed motor 2; 23 is a space control unit for controlling the operation of the space motor 7 and the operation of the head rotation motor 13 in conjunction with the operation of the space motor 7;

24 is a print control unit for controlling the ink ejection operation of the inkjet head IO.

FIG. 3 is a diagram of the inkjet head IO viewed from the platen roller l side, and 16 is an index for displaying the direction of the inkjet head IO.

Each nozzle 17 communicates with one of four color ink tanks, and a large number of nozzles 17 that eject ink of the same color are arranged in a vertical line, and horizontally, from the left side,
Yellow (Y), magenta (M), cyan (C) and black (K)
They are arranged in four rows.

In this way, the nozzles 17 are arranged in a matrix pattern vertically and horizontally, and as they move in the "forward" direction (to the left in FIG. 3) by the spacing operation, the control signals from the print control section 24 are transmitted. By inputting the ink to the drive circuit, ink of each color is ejected from the nozzle 17 of each color onto the same portion of the printing surface in a superimposed manner.

In this case, since the yellow nozzle 17 is at the head in the traveling direction, the inks are superimposed in the order of yellow, magenta, cyan, and black from the bottom, and color printing is performed.

When the space direction is switched to the "return" direction, the inkjet head 10 is immediately rotated 180 degrees by the head rotation motor 13 to be in an inverted state, as shown in FIG. 4, and printing is performed in that state. be exposed.

Therefore, the inkjet head IO moves rightward in FIG. 4. In this case as well, the yellow nozzle 17 is at the head in the traveling direction, and color printing is performed by overlapping ink in the order of yellow, magenta, cyan, and black from the bottom, as in the "forward" case.

However, in the case of "return", the space direction is opposite to that for "outward J", so the print control section 24 performs printing control in accordance with the direction.

FIG. 5 is a control processing flow diagram for performing the above operations. S indicates a step.

This process starts in conjunction with the start of the printing operation, and first detects whether the space direction is "forward" or "return" using Sl. This can be detected from internal signals within the space controller.

Next, when the space direction is "forward" in S2, S3
In step S4, the inkjet head 10 is brought into an upright state, normal forward printing control is performed, and the process returns to step S1.

When the space direction is "reverse" in S2, the inkjet head 10 is rotated 180 degrees to an inverted state in S5, and reverse direction printing control is performed in S5, and the process returns to S1.

〔Effect of the invention〕

According to the color inkjet printer of the present invention, ink of each color can be ejected in the same order onto the same part of the print surface when the inkjet head moves in the "forward" and "return" directions. can. Therefore, it is possible to perform bidirectional printing without changing the color tone even if the printing direction changes, and has the excellent effect of being able to perform high-quality, high-speed bidirectional color printing.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the present invention, Fig. 2 is a block diagram of an embodiment, Fig. 3 is a front view of the head during "forward" printing, and Fig. 4 is a block diagram of the present invention.
FIG. 5, a front view of the head during "back" printing, is a processing flow diagram of the embodiment. In the drawings, 10: inkjet head, 13: head rotating means, 17: nozzle, 20: head driving means. \(I1'tjl)IF! Front view of Gin's head Figure 3 Front view of Utoki's head Processing flow diagram of the embodiment

Claims (1)

[Claims] 1. An inkjet head (10) in which a plurality of nozzles (17) for ejecting ink of different colors are arranged side by side in a horizontal direction, and the inkjet head (10) is moved in a horizontal direction. In a color inkjet printer having a head driving means (20) for sequentially ejecting ink from each nozzle (17) onto the same portion of a printing surface, the inkjet head (10) is driven by the head driving means (20). While moving the above nozzle (
Head rotation means (13) for causing the ink to be ejected from the inkjet head (17) and for rotating the inkjet head (10) by 180 degrees in response to the direction in which the inkjet head (10) is moved by the head drive means (20). A color inkjet printer characterized by being equipped with. 2. In the inkjet head (10), a plurality of nozzles (17) for ejecting ink of the same color are arranged in a line in the vertical direction, and as a whole, there are a plurality of nozzles in each of the vertical and horizontal directions. Claim 1 in which (17) is arranged.
Color inkjet printer as described.