JPS61222746A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To regulate the lateral bias between head units by a method in which printing data from a host computer are put in any length shift-registers and any shift output lines of the shift registers are selected and latched. CONSTITUTION:Serial data Sa from a host computer are put in a 8-bit shift register 11a. The shift output Sb0-15 of the registers 11a1,2 are put in a selector 12, and Sc is selected by a selection signal Sm. The Sc so selected is put in the shift register 11b, and shift output Sd is latched by a data latch 13 to obtain parallel data Se. By varying the selection signal Sm, the data of the latch 13 can be changed, and therefore regulation of lateral bias can be attained. The needs to mechanically regulate lateral bias between the head units can thus be eliminated, and the regulation of the lateral bias can be simply made.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to the structure of an ink jet recording apparatus equipped with a replaceable print head unit.

[Prior art]

An inkjet recording device supplies ink to a plurality of ink ejection ports formed in a print head and drives the ink ejection ports based on data signals, thereby depositing ink droplets on paper for recording. .

In addition, there are two types of inkjet recording devices: the line print type, in which ink ejection ports for one line are arranged on the print head and records while scanning in the paper feed direction, and the line print type, in which the print head is mounted on a carriage and records in the width direction of the paper. There is also a serial print type that records while scanning.

Further, in devices for color printing such as color graphic recorders, a plurality of print heads are installed according to ink colors such as yellow, magenta, cyan, and black. Such an inkjet recording apparatus is generally configured such that a print head section including a print head, a head drive circuit, etc. is formed into a unit, and each unit can be replaced.

However, in inkjet recording devices, color misalignment occurs when each color is overlaid due to mechanical variations between each color head or mechanical misalignment after head unit replacement. Adjustments must be made to minimize the deviation.

However, with such conventional technology, there is a problem in that it takes time and effort to adjust the machine misalignment, and accurate adjustment is difficult.

〔the purpose〕

An object of the present invention is to provide an inkjet recording apparatus that solves the problems of the prior art and makes it possible to adjust lateral misalignment between head units of each color.

The present invention achieves the above object by inputting print data sent from a host computer into a shift register of arbitrary length, selecting and latching an arbitrary shift output line of this shift register.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings, taking as an example a case where the present invention is applied to a line print type color inkjet recording apparatus.

FIG. 1(A) shows the head assembly 8 of this embodiment,
This assembly includes yellow 4Y, magenta 4M,
It has a structure in which each print head unit for cyan 4c and black 4th can be replaced (detachable) within the assembly. Also, each print head unit) 4y, h, c, B
An image is recorded by depositing ink droplets on a sheet of paper (not shown) that is scanned in front of the paper (not shown).

In the illustrated example, each head unit has head elements 9 arranged in a staggered manner in two rows, one above the other, one element being formed of 128 bits (corresponding to the number of ink ejection ports), and 14 elements above and below are used. ing.

In FIG. 2, the print data Sa sent from the host computer 1 passes through the horizontal registration adjustment circuit 2 and then is transferred to each head unit (data memory 3Y corresponding to 4y to 4B).
, 3M, 3c, 3B.

The data written in the data memory 3Y to 3B is sent to the hard disk unit/), and a dot corresponding to the data is printed. data 8
y, 8m+8c, one of FEB,
Further, Sm is selected by the switch 7 and inputted as a horizontal registration adjustment signal.

FIG. 3 shows the data structure of the signal Sa from the host computer 1, showing yellow (Y), magenta (M), cyan (
C), black CB) serial signals are printed on paper 10.
Each color head unit) 4Y, M, C,! 1 and correspond as shown in the figure.

FIG. 4 is a block diagram of the lateral registration adjustment circuit, and FIG. 6 is an embodiment of the lateral registration adjustment circuit 2. In FIG.

Serial data Sa from the host computer is input to an 8-bit shift register lla.

The shift outputs sbo, , of 11a1a are input to the selector 12, and Sc is selected by the previous select signal Sm.

The selected Sc is input to the shift register llb, and the shift output Sd is latched by the data latch 13, thereby obtaining parallel data Se. That is, by varying the select signal Sm, the data in the latch 13 can be changed, so lateral registration adjustment can be performed.

For example, as shown in Figure 1 (B), if the cyan print head unit 4c is shifted by 2 dots as shown, the data printed by 4c must be shifted by 2 dots. .

In FIG. 3, the cyan head unit 4c is shifted to the left by two dots with respect to the paper 10, and in FIG.
The print data written to the 3M must be two dots later than the other head unit data.

For example, if the serial data Sa sent from the host computer l in FIG. 4 is as shown in FIG. 5, the shift output SbO~6 of the shift register lla will be as shown in FIG. 5(A). become.

Currently, yellow 4Y, magenta 4M, black 4
The select signal S to the print head unit of B is Sbl.
is selected, and the latch clock Sg of the data latch 13 is latched at t7 (Sg) in the figure. 5IIl! The signal Sc selected by the selector 12 at Sb1 is transferred to the signal Sc selected by the selector 12 in FIG.
) to obtain the latch signal Se7 rising.

Is the latch signal Se Sd? The side is the left side of the paper 10.

On the other hand, as for the select signal Ss to the cyan 4C print head unit, by selecting Sb3,
Sec, which is two dots behind 5e1rab, is shown in Figure 5 (
C) can be obtained. In other words, Fig. 2 (B
) can be adjusted by changing the value of the select signal S11.

Generally, as shown in FIG. 4, arbitrary lateral registration adjustment is possible depending on the number of shift registers 11a.

〔effect〕

As is clear from the above description, according to the present invention, there is no need to mechanically adjust lateral registration between head units, and an inkjet recording apparatus that can easily perform lateral registration can be obtained.

[Brief explanation of the drawing]

FIG. 1(A) is a perspective view showing an embodiment of an inkjet recording apparatus to which the present invention is applied, and FIG. 1(B) shows a state when the head unit shown in FIG. 1(A) is shifted laterally. 2 is a block diagram illustrating the print data processing system in this embodiment; FIG. 3 is a diagram illustrating the structure of print data sent from the host computer and the printing position on paper; FIG. 4 5 is a block diagram showing an example of the lateral registration adjustment circuit according to the present invention, FIGS. 5(A) to 5(C) are timing diagrams for explaining the operation of FIG. 4, and FIG. FIG. 2 is a block diagram showing a typical circuit configuration. DESCRIPTION OF SYMBOLS 1...Host computer, 2...Horizontal registration adjustment circuit, 3Y"B...Data memory, 4Y"'B...Print head unit, 5...Timing control section, 6...Digital switch , 8! ``e...Digital SW data, 7...Switcher, 8...Head assembly, 9.0 head element, 10...Print paper, 11a, b...Shift register, 12...Selector , 13... Data latch. Sa... Print data from host computer, sb
...Shift output of shift register lla, Sc...
Output data of selector 12, Sd...shift output of shift register llb, Se...data memory 3Y~
Parallel data sent to B, Sf...output from the timing circuit that selects digital Sw data $7Ne, Sg...latch clock of shift register llb, S
-... Output from switch 7 that selects Sc, wy
~8...Write signal to data memory 3Y"'B. Engraving of drawing (*no changes to the contents) Figure 4C
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- Paperback CI3 force 4 - Circle Li (Re-procedural amendment (method) June 10, 1985 Manabu Shiga, Commissioner of the Patent Office1, Indication of the case Patent application No. 1987-651252, Title of the invention Inkjet recording device 3, relationship with the amended person case Patent applicant (100) Canon Co., Ltd. 4, agent 3rd floor, Seiko Building 6, 5-1-31 Akasaka, Minato-ku, Tokyo 107 Telephone (03) 589-1201 (Representative) (7748) Patent Attorney Yoshi Tani - 5, Date of amendment order Voluntary 6, Full text of the specification to be amended, all drawings and power of attorney 7, Contents of amendment (1) Engraving of the specification and drawings (No change in content)

Claims (1)

[Claims] An inkjet recording apparatus equipped with replaceable head units, characterized in that a circuit for adjusting the lateral registration between each head unit is provided so that the lateral registration can be adjusted by external control. Inkjet recording device.