JPH082005A - Ink jet printer - Google Patents

Abstract

PURPOSE:To execut high-speed printing by making efficient use of a plurality of heads. CONSTITUTION:In an ink jet printer, a plurality of removable heads each having nozzle arrays discharging ink, a carriage 4 whereon a plurality of head mounting parts for mounting these heads are disposed in the main scanning direction A and a head driving means 5 which makes the carriage 4 move back and forth in the main scanning direction are provided. The printer is equipped moreover with a head driving control circuit which positions the heads by controlling the operation of the head driving means 5 and with a printing data control circuit which converts an operation control code in printing data from a host unit into driving data and outputs them to the head driving control circuit, while analyzing a printing code in the printing data and converting it into dot data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, and more particularly to an ink jet printer using a detachable head.

[0002]

2. Description of the Related Art FIG. 4 is a partial perspective view of a conventional ink jet printer. In a conventional inkjet printer, one head 50 having a plurality of nozzles 51 for ejecting ink is mounted on a carriage (not shown), and a printing operation is performed by reciprocating the carriage in the main scanning direction A.

[0003]

However, in the conventional ink jet printer, the printing speed is limited by the response speed characteristics of the head. Therefore, if the carriage feed speed is too fast with respect to the head response speed, the printing will not be performed. The printing speed of the inkjet printer is determined by the performance of the head because it cannot catch up. That is, the printing speed of the inkjet printer is determined by the response characteristics of the actuator element for each dot of the head. Therefore, when the response frequency is limited by the head device, there is a disadvantage that the speed cannot be further increased.

In order to solve such inconvenience, in the conventional example, it is general practice to provide head elements for two lines and a plurality of lines at the beginning of a sentence to increase the number of print lines when reciprocating at once. However, in this conventional example, there are problems such as an increase in head size.

Further, in an ink jet printer, even when an attempt is made to add a shade to a print image, the ink is ejected twice at the same position when the density is increased, and therefore, at a normal printing speed. There was the inconvenience that it was not possible to add such shades.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the disadvantages of the conventional example, and in particular to provide an ink jet printer capable of printing at high speed by utilizing a plurality of heads. .

[0007]

According to a first aspect of the present invention, a plurality of removable heads having nozzle rows for ejecting ink and a plurality of head mounting portions for receiving mounting of the heads are arranged in the main scanning direction. A carriage provided, a head drive means for reciprocating the carriage in the main scanning direction, a head drive control circuit for positioning the head by controlling the operation of the head drive means, and a print data in the print data from the host device. And a print data control circuit for converting the operation control code into drive data and outputting it to the head drive control circuit, and for analyzing the print code of the print data and converting it into dot data.

Further, the print data control circuit is provided with dot data dividing means for dividing the dot data according to the number of heads mounted on the carriage and outputting the dot data to each head, and the head drive control circuit is mounted on the carriage. The print speed control means for controlling the moving speed of the carriage according to the number of heads is provided.
This aims to achieve the above-mentioned object.

According to another aspect of the present invention, the print data control circuit copies the dot data in accordance with the number of heads mounted on the carriage and outputs the same dot data to each head. In addition, the head drive control circuit is provided with a print density adjusting means for controlling the moving speed of the head drive means based on the number of heads mounted on the carriage and an external command. This aims to achieve the above-mentioned object.

According to a third aspect of the present invention, there is provided an operation panel for receiving various commands by pressing down the switch and outputting the various commands to the print data control circuit.
The print data control circuit is provided with a switching means for switching the activation of the print speed control means and the print density adjusting means according to the command from the operation panel and the number of heads mounted on the carriage. This aims to achieve the above-mentioned object.

[0011]

The plurality of heads are mounted on the head mounting portions provided on the carriage. The head driving means reciprocates a carriage having a plurality of heads mounted therein in the main scanning direction, and a print data control circuit which receives print data from the host device converts an operation control code in the print data into drive data. Output to the head drive control circuit. In response to this, the drive control circuit positions the head by controlling the operation of the head drive means based on the drive data. On the other hand, the print data control circuit analyzes the print code of the print data and converts it into dot data. At this time, the dot data dividing means divides the dot data according to the number of heads mounted on the carriage and outputs the divided dot data to each head. In response to this, the print speed control means controls the moving speed of the carriage according to the number of heads mounted on the carriage.

Under the control of the print data control circuit and the head drive control circuit, the plurality of heads arranged in the main scanning direction on the carriage sequentially eject ink from each nozzle in accordance with a constant reaction speed. To do. These heads are printed by the head drive control means so that dots do not overlap, and the reaction speed interval of one head is time-divided according to the number of heads, so the printing speed is multiple times that of normal printing. Become speed.

[0013]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the configuration of the present embodiment. The inkjet printer 1 includes a plurality of detachable heads 2A and 2B each having a nozzle row that ejects ink i, and a head mounting portion 3 that accepts mounting of the heads 2A and 2B.
Carriage 4 having a plurality of A and 3B arranged in the main scanning direction A
And a head drive means 5 for reciprocating the carriage 4 in the main scanning direction.

This will be described in detail. In the present embodiment, the inkjet printer 1 is provided with a lead screw 5A having a thread groove formed on its surface in parallel with a platen (not shown), and along the lead screw 5A in the main operating direction A. The carriage 4 is screwed to enable reciprocal movement. Two heads 2 having nozzles for ejecting ink i are mounted on the carriage 4 in the main scanning direction.

The lead screw 5A has a gear at one end on the upstream side in the printing direction, and meshes with a gear provided on the rotary shaft of the drive motor 5B to form a gear train 5C. The rotary motion of the drive motor 5B is transmitted to the lead screw 5A via the gear train 5C, and the rotary motion is converted into the forward motion in the main scanning direction by the screwed portion of the lead screw 5A and the carriage 4.

The head mounting portions 3A and 3B are connected to the head 2A,
2B is removably attached by fitting or screwing (not shown). The driving force of the drive motor 5B is transmitted to the lead screw 5A via the gear train 5C, and reciprocates the carriage 4 in the main scanning direction A.

FIG. 2 is a block diagram showing the structure of a control system for controlling the operation of the mechanism shown in FIG. The inkjet printer 1 converts the operation control code in the print data e from the host device 10 and the head drive control circuit 6 that positions the heads 2A and 2B by controlling the operation of the head drive means 5 into drive data f. And a print data control circuit 7 for analyzing the print code of the print data and converting it into dot data g.

In addition, the print data control circuit 7 divides the dot data according to the number of heads mounted on the carriage and outputs it to each head.
In addition, the head drive control circuit 6 includes a print speed control unit 6A that controls the moving speed of the carriage according to the number h of heads mounted on the carriage.

Further, the head mounting portions 3A and 3B are provided with head type recognizing means 9A and 9B, and the head type recognizing means 9A and 9B indicate the type of head including the type of filled ink. recognize. Further, it outputs to the head type recognition means as a signal whether or not the head 2 is attached. The head type recognition circuit 11 counts the number of heads mounted on the carriage and outputs the totalized number to the print data control circuit 7.

The print data control circuit 7 receives the number of heads h for each head type and the print data e from the host device, and sends the drive data f corresponding to the state to the head drive control circuit 6. By the head drive control circuit 6 driving the heads 2A and 2B according to the drive data f,
Printing is done.

Next, the operation of the ink jet printer 1 of this embodiment will be described. When printing at high speed, a plurality of heads are filled with the ink i of the same color, and these heads 2 are mounted on the head mounting portion 3 for printing. These heads 2 are arranged in parallel in the main scanning direction A, and these are arranged so that the dots ejected from the respective heads by the head driving means 5 do not overlap, that is, they alternate in the main scanning direction. Are controlled to form dots. Therefore, by driving these heads in a time-divisional manner, the printing speed becomes multiple times as compared with the case of normal printing.

For printing, as shown in FIG. 3, two heads 2 arranged on the carriage 4 in the main scanning direction are provided.
A and 2B sequentially eject ink i from their respective nozzles according to a constant reaction speed. Two heads 2A, 2
In B, the two heads 1 perform printing in order from the upstream side in the printing direction at the reaction speed intervals of one head so that dots do not overlap, so if the response characteristics of the actuator elements of the heads are the same, The printing speed is twice as fast as the normal printing speed. That is, two identical heads are arranged in parallel, and at the time of high-speed printing, the draft mode of a normal printer is used to print every 1 [dot], and the two heads each have a phase of 1 [dot]. ing. As a result, good printing can be obtained at twice the speed without changing the characteristics of the head device.

As described above, in the embodiment corresponding to claim 1, several head mounting portions are arranged in the carriage in a direction parallel to the main scanning direction, and the heads can be detachably mounted on the head mounting portion. In addition, the head drive control circuit allows the heads to be time-divided, or the timings can be adjusted so that the dots formed by the ejection of the respective heads do not overlap or are overlapped at the same timing. By filling the heads with ink of the same color and performing control to alternately print the inks ejected from the respective heads so that they do not overlap, monochrome printing can be performed at a multiple speed.

According to the second aspect of the present invention, the print data control circuit 7 copies the dot data in accordance with the number h of heads mounted on the carriage 4 and outputs the same dot data to each head. Data copying means 7B
In addition, the head drive control circuit 6 controls the moving speed of the head drive means 5 based on the number of heads mounted on the carriage 4 and an external command.
It has.

For high density printing, a plurality of heads 2
Are filled with the same color ink i, and these heads are mounted on the head mounting portion 3 for printing. These heads are arranged in parallel in the main scanning direction, and these are controlled by the head driving means 5 so that the dots ejected from the respective heads overlap each other. Therefore, by driving these heads in a time-division manner or simultaneously, it is possible to perform printing with higher density than in the case of normal printing.

As described above, in the embodiment corresponding to claim 2, each head is filled with the ink i of the same color,
High-density monochrome printing can be performed by controlling the printing so that the inks ejected from the respective heads 2 overlap.

According to the third aspect of the present invention, the ink jet printer 1 is provided with an operation panel 8 which receives various commands by depressing a switch and outputs the various commands to the print data control circuit 7. A switching unit 7 switches the activation of the print speed control unit 6A and the print density adjustment unit 6B according to a command from the operation panel 8 and the number of heads h mounted on the carriage 4.
Equipped with C. Therefore, the inkjet printer 1
The user can easily switch between high-speed printing at a normal density and high-density printing at a normal speed, as needed.

[0028]

Since the present invention is constructed and functions as described above, according to this, the drive control circuit controls the moving speed of the carriage based on the drive data and the number of heads mounted on the carriage, and the print data is printed. The control circuit analyzes the print code of the print data, converts it into dot data, and divides the dot data according to the number of heads mounted on the carriage and outputs it to each head, so that dots do not overlap. Also, the reaction speed interval of one head is time-divided by the number of heads for printing, and therefore printing can be performed at a printing speed that is a multiple of the normal case. As described above, it is possible to provide an unprecedented excellent inkjet printer capable of high-speed printing by utilizing a plurality of heads.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a block diagram showing a control system of an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a printing example with the configuration shown in FIG.

FIG. 4 is a partial perspective view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Head 3 Head mounting part 4 Carriage 5 Head drive means 6 Head drive control circuit 6A Print speed control means 7 Print data control circuit 7A Dot data division means 10 Higher-level device

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B41J 3/10 101 H

Claims (3)

[Claims] 1. A plurality of detachable heads having nozzle rows for ejecting ink, a carriage having a plurality of head mounting portions for receiving mounting of the heads arranged in the main scanning direction, and a carriage reciprocating in the main scanning direction. Head drive means for moving, a head drive control circuit for positioning the head by controlling the operation of the head drive means, and an operation control code in print data from a host device for converting the drive data into drive data. An ink jet printer having a print data control circuit for outputting to a drive control circuit and analyzing a print code of the print data to convert it into dot data, wherein the print data control circuit is a head mounted on the carriage. In addition to providing dot data dividing means for dividing the dot data according to the number and outputting it to each head, Inkjet printer the head drive control circuit, characterized by comprising a printing speed control means for controlling a moving speed of the carriage in accordance with the number of heads mounted on the carriage. 2. The print data control circuit comprises dot data copying means for copying the dot data according to the number of heads mounted on the carriage and outputting the same dot data to the respective heads. 2. The ink jet printer according to claim 1, wherein the head drive control circuit includes a print density adjusting unit that controls the moving speed of the head drive unit based on the number of heads mounted on the carriage and an external command. 3. An operation panel for receiving various commands by pressing down a switch and outputting the various commands to a print data control circuit, wherein the print data control circuit is mounted on the carriage and the command from the operation panel. 3. The ink jet printer according to claim 2, further comprising a switching unit that switches activation of the print speed control unit and the print density adjustment unit according to the number of heads that have been formed.