JP2002178546A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer in which high speed processing is ensured and the degree of freedom of design can be enhanced. SOLUTION: Since a drive control means comprises memories 105Y, 105M, 105C and 105K for developing image data and circuits 104Y, 104M, 104C and 104K for converting image data depending on LUT, the memories 105Y, 105M, 105C and 105K can be used to store image data being used only for controlling corresponding nozzles 108Y, 108M, 108C and 108K and thereby high speed processing is ensured. When nozzles 108Y, 108M, 108C and 108K are increased/ decreased or the arranging order is altered, it can be effected integrally with a corresponding drive control means. Since remodeling is not required in principle for others, the function can be extended or altered easily and the degree of freedom of design is enhanced.

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 capable of discharging a multicolor ink to perform color printing.

[0002]

2. Description of the Related Art In recent years, printers capable of receiving digital image data and performing full-color printing have been used. Digital image data is subjected to image processing by an internal CPU, and full-color printing is performed on recording paper from, for example, an inkjet head (hereinafter, referred to as a head). A resolution of 300 dpi or more has been used.

[0003]

By the way, a head capable of full-color printing has nozzles for discharging ink of three or more colors arranged in the main scanning direction. Such nozzles are individually driven and controlled. However, in the related art, the drive data of the nozzles of each color is created by reading the image data into one memory and then reading and processing the image data as appropriate.

[0004] However, if there is only one memory, there is a problem that even if the memory has a large capacity, the processing cannot be speeded up. For example, an ink jet printer capable of ejecting light and dark inks for YMCK color has been developed. In this case, however, the configuration of a driving unit for controlling the nozzles of eight colors is dedicated to it. Would. Therefore, when it is desired to add a nozzle of one color or to change the order of the nozzles to such an ink jet printer, a large-scale remodeling of the drive unit is generally required, which is equivalent to a new design. It takes time and effort.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an ink jet printer capable of increasing processing speed and improving design flexibility. I do.

[0006]

In order to achieve the above object, an ink jet printer according to the present invention comprises a plurality of nozzles capable of ejecting inks of different colors, and a plurality of drive controls provided for each nozzle. Means, each drive control means, a memory for developing image data,
And a data conversion circuit for converting the image data according to the LUT.

[0007]

According to the ink jet printer of the present invention, there are provided a plurality of nozzles capable of respectively ejecting inks of different colors, a plurality of drive control means provided for each nozzle,
Each drive control means includes a memory for developing image data and a data conversion circuit for converting the image data according to the LUT, so that the developing memory is used only for controlling the corresponding nozzle. This can be used for storing image data to be processed, thereby speeding up processing. In addition, for example, when the number of nozzles is increased or decreased or the arrangement order is changed, it can be performed integrally with the corresponding drive control means. Changes can be made easily, and the degree of freedom in design improves.

Further, it is preferable that each drive control means further includes an address control section for controlling an address of image data.

It is preferable that a data control unit capable of distributing image data for each color to each drive control unit is included.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram illustrating an example of a mechanical configuration near a head in an inkjet printer according to the present embodiment. The carriage 2 is a resin case housing the head 10 and a head driver (not shown). A head driver, which is a driving unit housed in the carriage 2, includes, for example, an IC including a processing circuit (FIG. 2) described later.
And is connected to the control board 9 by a flexible cable 5 pulled out from the carriage 2.

The carriage 2 is reciprocated by the carriage driving mechanism 6 in the main scanning direction (X direction) indicated by an arrow in the drawing. The carriage drive mechanism 6 includes a motor 6a, a pulley 6b, a toothed belt 6c, and a guide rail 6d, and the carriage 2 is fixed to the toothed belt 6c.

When the pulley 6b is rotated by the motor 6a, the carriage 2 fixed to the toothed belt 6c is moved along the arrow X direction in the figure. Guide rail 6d
Are two columns parallel to each other and penetrate through the insertion hole of the carriage 2 so that the carriage 2 slides.

For this reason, the toothed belt 6c is
The carriage 2 does not bend under its own weight, and the direction of the reciprocating movement of the carriage 2 is on a straight line. The direction in which the carriage 2 moves can be changed by reversing the rotation direction of the motor 6a, and the moving speed of the carriage 2 can be changed by changing the number of rotations. The ink cartridge 4 (not shown) has an ink tank inside. The ink supply port of the ink tank is opened when the ink cartridge 4 is set on the carriage 2 and connected to the ink supply pipe. When the connection is released, the ink supply port is closed and the ink is supplied to the head 10.

A head 10 is provided on the carriage 2. On the back surface of the head 10, Y, M,
Ink cartridges containing inks of the respective colors C and K are detachably arranged. The illustration of the ink cartridge is omitted. Flexible cable 5
Is a data transfer means, in which a wiring pattern including a data signal line, a power supply line and the like is printed on a flexible film, and the data is transferred between the carriage 2 and the control board 9; Follow the movement.

The encoder 7 is provided with graduations at a predetermined interval on a transparent film of resin, and the graduations are detected by an optical sensor provided on the carriage 2 so that
Detects the moving speed, position, and moving direction of. Paper transport mechanism 8
Is a mechanism for transporting the recording paper P in the sub-scanning direction indicated by the arrow Y in the figure, and includes a transport motor 8a and transport roller pairs 8b and 8c.
It is comprised including. The transport roller pair 8b and the transport roller pair 8c are driven by the transport motor 8a, and are a pair of rollers that are substantially equal by a gear train (not shown), but rotate at a slightly higher peripheral speed.

The recording paper P is nipped by a pair of conveying rollers 8b rotated at a constant speed after being sent out from a paper feeding mechanism (not shown), and is conveyed in a sub-scanning direction by a paper feeding guide (not shown). Is corrected and then conveyed while being nipped by the conveying roller pair 8c.

Since the peripheral speed of the pair of conveying rollers 8c is very slightly higher than that of the pair of conveying rollers 8b, the recording paper P passes through the recording section without causing slack. The speed at which the recording paper P moves in the sub-scanning direction is set to a constant speed.

While moving the recording paper P at a constant speed in the sub-scanning direction in this way, the carriage 2 is moved at a constant speed in the main-scanning direction, and the ink ejected from the head 10 is attached to one side of the recording paper P. An image is recorded in a predetermined range of the image.

FIG. 2 is a block diagram showing an outline of a circuit for processing image data in the ink jet printer according to the present embodiment. In the embodiment described below, in the head 10, Y (yellow) M (magenta) C
It is assumed that nozzles are arranged in the main scanning direction in the order of (cyan) and K (black). Note that, for simplicity of explanation, 4
Although the example including the nozzle capable of discharging the color ink is described, the invention is not limited to this.

In the processing circuit shown in FIG.
The CPU 100 integrally controls the CPU 100 via the CPU bus B. In a non-volatile memory (not shown) of the CPU 100, positional deviation data (shift amount from a reference position) for each nozzle measured at the time of manufacturing the inkjet printer is stored for the forward direction and the backward direction in the main scanning direction, respectively. ing. The operation of the ink jet printer will be described. Image data is transmitted from a SCSI cable (not shown) connected to an external personal computer or the like.
The data is input to the SCSI circuit 102 via the SI connector 101.

The image data input to the SCSI circuit 102 is further input to the data control unit 103, and the
The drive control units 104Y, 104M, 104C, and 104K, which are combination means provided in parallel for each ink color, in accordance with the contents of the distribution control register set by 100.
Is input to

On the other hand, the drive control units 104Y, 104M, 1
Expansion memories 105Y, 105M, 105C, and 10C, which are storage means connected to the storage memories 04C and 104K, respectively.
In 5K, for example, when the power supply of the ink jet printer is turned on, positional deviation data is read from the CPU 100, and image data indicating that no ink is ejected, that is, zero value (hereinafter referred to as correction data) is stored by the corresponding number. It has become. Drive control unit 104
Y, 104M, 104C, 104K, and expansion memory 1
05Y, 105M, 105C, and 105K constitute a driving unit. Preferably, the drive control means includes an address control unit for controlling the address of the image data.

Drive controllers 104Y, 104M, 104
In C and 104K, synthesis is performed so that correction data is added before the image data supplied from the data control unit 103, and image data that does not eject any ink after the image data, that is, a zero value (hereinafter, referred to as a zero value).
After data). This will be described in more detail.

FIG. 3A is a diagram schematically showing image data shown in a stored state, and FIG. 3B is a diagram schematically showing image data after being synthesized by the drive control unit. FIG. From the data control unit 103, a drive control unit 104Y,
As shown in FIG. 3A, image data YD, MD, and C for one row (for a plurality of rows when the nozzles are arranged over a plurality of rows) as shown in FIG.
D and KD are input, respectively. On the other hand, the drive control unit 10
4Y, 104M, 104C, and 104K read the correction data from the corresponding development memories 105Y, 105M, 105C, and 105K, and add the correction data before the image data.

Here, since the Y color nozzle is located at the head in the forward direction of the main scanning direction, that is, at the previous reference position, it is necessary to add correction data before (in this case, ahead of image data in the forward direction). There is no. For the nozzles of other colors, the correction data Msd, Csd, and Ksd that have become longer in accordance with the nozzle position shift are converted to image data MD,
It is added before CD and KD (the left end in FIG. 3B). On the other hand, after the image data YD, MD, and CD (in this case, meaning that it comes after the image data in the forward direction), the subsequent data Yrd, Mrd, and Crd are added. The K color nozzle is located at the rear reference position when the carriage moves to the rightmost position, so that there is no need to add rear data. The post-data has the same zero value as the correction data, but does not need to strictly correspond to the positional deviation, and is used for keeping the data length constant. Above,
This means that the forward synthesized image data for driving the nozzles has been created.

Next, the creation of the composite image data in the backward direction will be described. Since the K color nozzle is at the head in the backward direction of the main scanning direction, that is, at the rear reference position, it is not necessary to add correction data before (in this case, ahead of image data in the backward direction). With respect to the nozzles of other colors, the correction data Ysd ′, Msd ′, and Ksd ′ that have become longer according to the nozzle position shift are converted into image data
It is added before D, CD, and KD (the right end in FIG. 3B).
On the other hand, after the image data MD, CD, and KD (in this case, coming after the image data in the backward direction),
Subsequent data Mrd ', Crd', and Krd 'are added. As a result, the backward composite image data for driving the nozzles is created.

The synthesized image data thus formed is converted based on the LUT stored in advance, input to the p / s circuits 106Y, 106M, 106C and 106K, respectively, and waits for the timing to be supplied to the nozzles. Becomes When the carriage 2 or the head 10 starts moving in the forward direction and determines that it has reached the previous reference position based on a signal from a sensor (not shown), the CPU 100
The I / O control circuit 107 is driven, and the timing signal is transmitted to the p / s circuits 106Y, 106M,
6C and 106K at the same time.

Then, the p / s circuits 106Y, 106M,
106C and 106K simultaneously output the combined image data to the nozzles 108Y, 108M, 108C and 108K.
Here, of the combined image data, the nozzle 108Y of the Y color
Since the correction data is not added to the output of the nozzle 108Y, the nozzle 108Y immediately starts ejecting ink based on the image data YD. However, other nozzles
First, since the head 10 is driven based on the correction data, the head 10 moves in the forward direction while maintaining a state in which ink is not ejected.

Thereafter, the M nozzle 10 is moved from the front reference position.
When the head 10 moves in the forward direction by the displacement of 8M, the driving based on the correction data Msd ends, so that the nozzle 108M starts ejecting ink based on the image data MD. Further, the nozzle C of the C color from the front reference position
When the head 10 moves in the forward direction by the amount corresponding to the position shift of, the driving based on the correction data Csd ends, so that the nozzle 108C starts discharging ink based on the image data CD. Further, when the head 10 moves in the forward direction by the positional deviation of the K color nozzle 108K from the previous reference position, the driving based on the correction data Ksd ends, so that the nozzle 108K starts ink ejection based on the image data KD. .

Thereafter, the nozzle 1 based on the image data YD
When the ink ejection of 08Y is completed, the nozzle 108Y is maintained in a state in which no ink is ejected, based on the subsequent data Yrd. Subsequently, the nozzle 108 based on the image data MD
When the ink ejection of M is completed, the nozzle 108M is maintained in a state of not ejecting ink based on the subsequent data Mrd. Subsequently, the nozzle 10 based on the image data CD
When the ink ejection of 8C is completed, the nozzle 108C is maintained in a state of not ejecting ink based on the post-data Crd. Finally, the nozzle 108K based on the image data KD
When the ink discharge is completed, the carriage 2 reaches the rear reference position, and then the scanning direction is reversed in the backward direction. Also in the backward direction, nozzle drive control is performed based on the composite image data in the same manner as described above.

According to the present embodiment, the expansion memory is
It can be used for storing image data used only for the control of the corresponding nozzle, whereby the processing speed can be increased. Further, for example, when the number of nozzles is increased or decreased or the arrangement order is changed, it can be performed integrally with the corresponding expansion memory and the drive control unit. Changes can be made easily, and the degree of freedom in design improves.

It should be noted that it is theoretically possible to store the correction data entirely in the non-volatile memory of the CPU 100. However, since the data amount becomes large, the correction data is 16 bits x n +
It is preferable to store the numerical values n and m after the expression of m, since the memory capacity can be saved.

Although the present invention has been described with reference to the embodiments, it should be understood that the present invention should not be construed as being limited to the above embodiments, and that modifications and improvements can be made as appropriate. is there.

[0034]

According to the present invention, it is possible to provide an ink jet printer capable of increasing the processing speed and improving the degree of freedom in design.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a mechanical configuration near a head in an ink jet printer according to an embodiment.

FIG. 2 is a block diagram illustrating an outline of a circuit for processing image data in the ink jet printer according to the embodiment.

FIG. 3A is a diagram schematically illustrating image data shown in a stored state, and FIG. 3B is a diagram schematically illustrating image data after being synthesized by a drive control unit. FIG.

[Explanation of symbols]

2 Carriage 5 Flexible cable 6 Carriage drive mechanism 10 Head 100 CPU 103 Data control unit 104Y, 104M, 104C, 104K Drive control unit 105Y, 105M, 105C, 105K Expansion memory 106Y, 106M, 106C, 106K p / s circuit 108Y, 108M, 108C, 108K nozzle

Claims (3)

[Claims] A plurality of nozzles capable of respectively ejecting inks of different colors; and a plurality of drive control means provided for each of the nozzles. An ink-jet printer comprising: a memory; and a data conversion circuit for converting image data according to an LUT. 2. The ink jet printer according to claim 1, wherein each drive control unit further includes an address control unit for controlling an address of the image data. 3. The ink jet printer according to claim 2, further comprising a data control unit capable of distributing image data for each color to each drive control unit.