JPH11314361A - Ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize high quality printing by providing a selecting means for prohibiting ejection of ink from each nozzle of an ink jet recording head regardless of the recording data thereby selecting an optimal nozzle pitch depending on the recording method. SOLUTION: A driving waveform generating circuit 411 outputs a trapezoidal head driving waveform common to a plurality of nozzle arrays receiving a waveform starting signal 301 from a control means and a generated driving waveform is applied to a piezoelectric element 21 through an analog switch 415. A nozzle selection data register 412 comprising 48 bits for one nozzle array and selecting use or nonuse of each nozzle receives a nozzle selection data 306 in synchronism with a nozzle selection data transfer clock 305. According to the output from the register 412, the analog switch 415 is controlled to switch application or nonapplication of a driving signal to the piezoelectric element 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus using an on-demand type ink jet recording head.

[0002]

2. Description of the Related Art An on-demand type ink jet recording head has a plurality of nozzle openings and pressure generating chambers communicating with the respective nozzle openings, and expands and contracts the pressure generating chamber in response to a print signal to discharge ink droplets. Is configured to generate.

In a recording apparatus using this ink jet recording head, it is common practice to increase the number of nozzle openings in order to improve the recording speed. Here, if the number of nozzle openings is increased without changing the distance between the nozzle openings of the ink jet recording head, the size of the ink jet recording head becomes large, resulting in an increase in cost.

[0004] Therefore, by increasing the number of nozzle openings and reducing the distance between the nozzle openings, an increase in the size of the ink jet recording head is suppressed. Also, the distance between the nozzle openings has been reduced to improve the recording density for higher image quality.

[0005]

However, when the distance between the nozzle openings is reduced, printing is performed with a smaller area with less scanning. Recording is performed one after another before the drying of the ink droplets above is completed, and ink bleeding occurs, thereby deteriorating the recording quality. Therefore, it is necessary to widen the distance between the nozzle openings according to the recording paper, that is, to perform printing by thinning out the nozzles. Must be processed.

[0006]

According to the first aspect of the present invention, there is provided an ink jet recording apparatus capable of ejecting ink droplets, a mechanism for moving the ink jet recording head in a main scanning direction with respect to a recording sheet, and a recording apparatus. It is characterized in that it has a mechanism for moving the paper in a sub-scanning direction different from the main scanning direction, and has a selecting means for each nozzle to enable non-ejection regardless of print data.

Further, the present invention is characterized in that print data is sent only to nozzles used for printing.

[0010] According to the above configuration, when printing is performed with the nozzles thinned out, by setting in advance the non-selection of the nozzles, it is not necessary to send or generate data for making the non-ejections for the thinned nozzles every time. This eliminates the need for a means for processing data from the printer, thereby providing an inexpensive inkjet recording apparatus. In addition, you can select the nozzle to use according to the recording paper,
There is an effect that optimal recording can be performed on various recording papers.

[0009]

FIG. 1 shows a structure around a printing mechanism of a printer according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a carriage for performing main scanning, which is provided via a timing belt 2. The recording paper 5 is connected to a pulse motor 3 and is guided by a guide member 4 to reciprocate in the paper width direction of the recording paper 5.

An ink jet type recording head 6 to be described later is attached to the surface of the carriage 1 which faces the recording paper 5, in this embodiment, the lower surface. The ink jet recording head 6 forms a dot by receiving ink supply from an ink cartridge 7 mounted on the carriage 1 and ejecting ink droplets on the recording paper 5 in accordance with the movement of the carriage 1 to form a dot. An image or text is printed on paper 5.

Reference numeral 8 denotes a capping device which is provided in a non-printing area and seals a nozzle opening of the recording head 6 during printing pause, and ink droplets from the recording head 6 by a flushing operation performed during a printing operation. Is to receive.

Reference numeral 9 denotes cleaning means, which is provided in the vicinity of the capping device 8 and is configured to wipe the surface of the nozzle plate of the recording head 6 with a blade or the like to wipe off ink residue and paper dust on the nozzle plate surface. I have.

Reference numeral 10 denotes a pulse motor for performing sub-scanning, which conveys the recording sheet 5 via a reduction gear (not shown) in accordance with the operation of the carriage 1.

FIG. 2 shows an embodiment of a control device for controlling the above-mentioned ink jet recording apparatus.
Reference numeral 0 denotes a control unit which receives a print command signal or print data from the host and controls a buffer memory 32, a head drive circuit 41, a carriage drive circuit 42, and a paper transport drive circuit 43, which will be described later, to execute a print operation. It is to let.

The buffer memory 32 is a memory for temporarily storing print data from the host, and outputs the stored print data to the head drive circuit 41 according to a print timing signal.

The drive circuit 41 is configured to selectively apply a drive voltage to the piezoelectric vibrator 21 that drives a nozzle of the ink jet print head 6 that discharges ink droplets in accordance with print data.

FIG. 3 shows an embodiment of the nozzle arrangement of the recording head of the above-mentioned ink jet recording apparatus, which is composed of three nozzle rows. Each nozzle row has 48 nozzles in the sub-scanning direction V. Are arranged in parallel. The nozzle pitch in the sub-scanning direction of the nozzle row is 1/120 inch.
In the three nozzle rows, nozzle row A and nozzle row B are 1/36
0 inches, the nozzle rows A and C are displaced in the sub-scanning direction by 2/360 inches, and three main nozzles are used in one main scan in the sub-scanning direction every 1/360 inch. Can be recorded.

FIG. 4 is a diagram showing the details of the drive circuit 41, and is a diagram showing a circuit for the A row of the nozzle rows A, B, and C. Although not shown, columns B and C are the same as the circuits in column A.

In the figure, reference numeral 411 denotes a driving waveform generating circuit for generating a trapezoidal head driving waveform.
15 is applied to the piezoelectric element 21. The drive waveform generation circuit 411 generates a waveform in common for each of the nozzle rows A, B, and C. Each time a waveform start signal 301 is input from the control means 30, a drive waveform is output.

Reference numeral 412 denotes a nozzle selection data register of data for selecting use or non-use of each nozzle, and is constituted by 48 bits corresponding to one nozzle row corresponding to each nozzle. The nozzle selection data signal 306 and the nozzle selection data transfer clock signal 305 are connected from the control unit 30, and the nozzle selection data 306 is input in synchronization with the nozzle selection data transfer clock 305.

Reference numeral 413 denotes a print data shift register, which comprises a 48-bit register for one nozzle row and a data selector for selecting / non-selecting print data based on the value of a nozzle selection data register. Control means 3
From 0, the recording data 304 is sequentially transferred in synchronization with the recording data shift clock 303.

Reference numeral 414 denotes a recording data shift register 413
This is a data register that holds the value of... After the transfer of the recording data to the recording data shift register 413 is completed, the recording data is retained by the data latch signal 302 from the control unit 30.

Reference numeral 415 denotes an analog switch for applying or not applying a signal for driving the piezoelectric element 21 generated by the drive waveform generation circuit 411 to the piezoelectric element 21 based on the value of the data register 414.

FIG. 5 is a diagram showing details of the drive circuit 41 described above for the print nozzle selection means of the print data shift register 413 for two n-th and (n + 1) -th nozzles.

The n-th output signal of the nozzle selection data register 412 is output from the n-th data selector 413An of the data selector 413 in the print data shift register.
13Bn is connected as a control signal. Similarly, the (n + 1) th output signal of the nozzle selection data register is connected as a control signal for the (n + 1) th data selector 413An + 1, 413Bn + 1 of the print data shift register 413.

413An and 413Bn are data selectors for the n-th register of the recording data shift register 413, and 413An is a recording data register 413.
Is a data selector for selecting the n-th input data. When the value of the nozzle selection data register 412n is 1, the print data 304n is selected. When the value is 0, the print data 304n is fixed to 0 regardless of the print data 304n. Become.

On the other hand, 413Bn is the recording data register 4
13 is a data selector for selecting data to be output from the n-th register to the next register n + 1. When the value of the nozzle selection data register 412n is 1, the n-th output of the print data register is selected. Is selected from the (n-1) th data of the recording data register 413 (not shown).

FIG. 6 is a diagram showing a data flow of the print data shift register 413 when nozzle selection / non-selection is set. In the case of (1), n-1, n and n + 1 are shown.
Are selected for all of the nozzles, and the transfer of print data is performed in the order of n−1, n, and n + 1.
Sent in synchronization with 03. In the case of (2), n−1,
The nozzle n + 1 is selected and the nozzle n is set to non-selection. The transfer of print data is performed in such a manner that the data to be transferred by the control means 30 is n + 1 in the next data of the register n-1. It is set in advance or sent from the host.
And n is fixed to the 0 level so that recording is not performed regardless of the recording data. The print data transfer clock 303 is obtained by subtracting the number of non-selected nozzles from all 48 bits of the print data shift register 413.

FIG. 7 is a diagram showing an example of a nozzle arrangement when the nozzles are thinned out, and every other nozzle in each nozzle row is thinned out.

In rows A and C, nozzles # 1, # 3, # 5,
.., # 47 are used for recording, and nozzles # 2,
.., # 46, and # 48 are set to be used for recording. In this case, the nozzle pitch of each nozzle row is 2/120 inches, and the total of the three rows is 2/360 inches, and printing is performed at twice the nozzle pitch when all the nozzles are used.

The setting data for the nozzle selection register is A
.. 10 for the column and the C column, and 010101... 01 for the B column. At this time, the print data transfer clock 303 is output for 24 bits, which is half of 48 bits for all nozzles. As for the print data, the data is transferred from the host for every 24 nozzles in the sub-scanning direction for each row for every 2/120 inches.

[0032]

As described above, it is possible to arbitrarily set whether each nozzle is used for printing or not,
The optimum nozzle pitch can be selected according to the recording paper and the recording method, and there is an effect that high-quality recording can be performed. Also, there is no need to send print data for the thinned nozzles from the host, and there is no need to generate print data on the printing device side, so that data transfer from the host can be performed at high speed and the configuration of the printing device is simple. It has the effect of being good.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a block diagram of an apparatus showing one embodiment of the present invention.

FIG. 3 is a diagram showing one embodiment of a nozzle arrangement of the recording head of the present invention.

FIG. 4 is a block diagram of a head drive circuit of the device showing one embodiment of the present invention.

FIG. 5 is a diagram showing details of a head drive circuit of an apparatus according to an embodiment of the present invention.

FIG. 6 is a diagram showing a flow of print data of a head drive circuit of the device according to the embodiment of the present invention.

FIG. 7 is a diagram illustrating an example of a case where nozzles used for recording of the recording head of the present invention are thinned out.

[Explanation of symbols]

 Reference Signs List 6 inkjet recording head 8 capping device 9 cleaning device 21 piezoelectric vibrator

Claims (2)

[Claims] An ink jet recording head having a pressure generating chamber formed by a nozzle plate provided with a plurality of nozzle openings and a vibrating plate deformed by expansion and contraction of a piezoelectric vibrator, and capable of discharging ink droplets; An ink jet recording apparatus comprising: a mechanism for moving a recording head in a main scanning direction with respect to a recording sheet; and a mechanism for moving the recording sheet in a sub-scanning direction different from the main scanning direction. An ink jet recording apparatus comprising a selection unit capable of non-discharging regardless of the type. 2. The ink jet recording apparatus according to claim 1, wherein the recording data is sent only to nozzles used for recording.