JPH0948120A - Recording head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store the characteristic data such as the positional relation of a head unit. SOLUTION: A data memory part 12 composed of a writable memory unit such as an ROM and storing the data related to the respective head units 1Y, 1M, 1C, 1B in a head carriage 1 is arranged to the proper place in the head carriage 1 and connected to the recording control part of an apparatus main body by a signal line 12a. The distances between the head unit 1Y and the head units 1M, 1C, 1B and the data related to the use nozzles in the arranged nozzles of the head units are stored in the data memory part 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head used in an inkjet recording apparatus applied to a facsimile, a copying machine, a printer or the like, and an inkjet recording apparatus equipped with this recording head.

[0002]

2. Description of the Related Art Conventionally, in an ink jet recording apparatus for ejecting ink droplets from a nozzle of a head unit to print on a sheet, the head unit is first fixed to a head carriage, and this head carriage is arranged in the apparatus. It was

Here, the characteristics such as the nozzle position used in the head unit may differ for each head carriage. Further, for example, in a case where a plurality of head units capable of color printing are provided, there is a possibility that characteristics such as a positional relationship between the head units may be different for each head carriage. In order to prevent such a difference from affecting the image, each head carriage may be configured so that the nozzle positions used in the head unit and the positional relationship between the head units are exactly the same.

[0004]

However, in reality, it is extremely difficult to accurately configure each head carriage, and therefore, in order to prevent the image from being adversely affected by the above-mentioned difference, the above-mentioned problem is solved. Information about the characteristics of each head carriage needs to be input to the control unit of the apparatus main body, which is troublesome. Furthermore, in that case, when the head carriage is replaced, information regarding the characteristics corresponding to the replaced head carriage must be input again to the apparatus main body side, which is very troublesome.

An object of the present invention is to solve the above problems and to provide a recording head capable of storing characteristic information such as a positional relationship between the head units.

Another object of the present invention is to provide an ink jet recording apparatus provided with a recording head capable of storing characteristic information such as a positional relationship between head units.

[0007]

The present invention comprises a head unit in which nozzles for ejecting ink droplets are arranged in a line, and a storage unit for storing characteristic information about the head unit (claims). Item 1).

Further, the recording head has a plurality of head units arranged at predetermined positions, and the storage means comprises:
The positional relationship between the head units is stored as characteristic information (claim 2).

According to the structure of the first or second aspect, the characteristic information regarding the head unit is written in the storage means when the recording head is manufactured. Therefore, when assembling the apparatus or exchanging the recording head, the characteristic information regarding the head unit is input to the apparatus main body side, so that the trouble of inputting is unnecessary.

Further, the recording head according to claim 1 or 2, a capturing means for capturing the characteristic information stored in the storage means, and ink droplet ejection from the nozzle to the recording medium using the captured characteristic information. The discharge control means for controlling is provided (Claim 3).

According to this structure, the characteristic information stored in the storage means is fetched, and the ejected characteristic information is used to control the ink droplet ejection from the nozzle to the recording medium. For example, in the case of a recording head provided with a plurality of head units, information regarding the positional relationship between the head units is fetched, and the information is used to control the ink droplet ejection from the nozzles to the recording medium to perform recording. High quality printing is performed on the medium.

[0012]

2 is a perspective view showing the structure of a head carriage used in an embodiment of an ink jet recording apparatus according to the present invention. FIG. 3 shows the head carriage 1.
3 is a partial front view showing a part of the nozzle surface of FIG.

The head carriage 1 is provided with head units 1Y, 1M, 1C and 1B for ejecting yellow, magenta, cyan and black inks, respectively, and holds each head unit in a fixed manner.

Each head unit 1Y, 1M, 1C, 1B
Is, for example, one in which the nozzles 11 are arranged at a predetermined interval, and each nozzle communicates with a pressure chamber (not shown),
Each pressurizing chamber further communicates with an ink liquid chamber (not shown) in which ink is stored.

A data storage section 12 is provided at an appropriate position in the head carriage 1. The data storage unit 12 is composed of a writable memory element such as a PROM, and each head unit 1Y, 1 in the head carriage 1 is provided.
It stores information about M, 1C and 1B. The data storage unit 12 is connected to a recording control unit 511 described later by a signal line 12a.

An example of information stored in the data storage unit 12 is shown below. Positional Relationship Between Each Head Unit The head carriage 1 is provided in advance with each head unit 1Y, 1
It is manufactured by providing rectangular holes for arranging M, 1C and 1B. The head units 1Y, 1M, 1C, and 1B each having a separately manufactured nozzle are embedded in the rectangular holes of the head carriage 1 to form a recording head. The positional relationship between the head units 1Y, 1M, 1C and 1B that influence the above becomes a problem. For example, if the recording device has a resolution of 600 dpi, the nozzle interval is about 42 μm.
The nozzle position requires an accuracy of about 20 μm. Therefore, it is important to manage the distance between each head unit.
Distance d1 between head units 1Y and 1M, distance d2 between head units 1Y and 1C, head units 1Y and 1B
The distance d3 between them is measured and stored in the data storage unit 12.

Both ends of the used nozzle In general, since the head unit is provided with a larger number of nozzles than the number actually used, it is necessary to set the used nozzles. Further, as shown in FIG. 3, each head unit may be disposed on the head carriage 1 while being displaced in the nozzle arrangement direction (horizontal direction in the drawing). In this case, for example, the head unit 1Y includes the nozzles 11Y and the head unit 1 so that the number of used nozzles becomes a predetermined number and the right ends of the used nozzles of the head units coincide with each other.
M is the nozzle 11M, and head unit 1C is the nozzle 11
C, the head unit 1B sets the nozzle 11B as the right end of the used nozzle.

Therefore, by storing information about both ends of the used nozzles in each head unit arranged in the head carriage 1, that is, information about from the end of the arranged nozzles to be used, in the data storage section 12,
The nozzle positions in the nozzle arrangement direction of each head unit can be accurately matched.

These pieces of information are measured after the head carriage 1 is manufactured and before the head carriage 1 is incorporated into the main body of the recording apparatus, and are stored in the data storage section 12.

As described above, since the data storage unit 12 is provided in the head carriage 1 and the information about each head unit arranged in the head carriage 1 is stored in the data storage unit 12, when the recording apparatus is assembled. There is no need to enter the information about the head unit into the control unit or the like on the apparatus body side.

FIG. 4 is a perspective view showing the structure around the printing position in one embodiment of the ink jet recording apparatus according to the present invention. This inkjet recording apparatus prints a color image by ejecting ink droplets of each color from a nozzle 11 arranged in each head unit 1Y, 1M, 1C, 1B of a head carriage 1 onto a recording medium such as a paper P. .

The head carriage 1 is formed in, for example, a rectangular parallelepiped shape and has two support shafts 13 fixed to the main body of the apparatus.
14 is supported by penetrating the proper positions on both ends.

A conveying belt 21 is arranged at a position separated by a predetermined dimension in the ink ejection direction from the nozzle 11 of each head unit. The transport belt 21 is arranged such that the belt surface is orthogonal to the ink ejection direction and the paper transport direction indicated by the arrow in FIG. 4 is orthogonal to the nozzle array direction, and the width dimension is the nozzle array direction of each head unit. It is an endless shape slightly longer than the size of the effective nozzle, and is stretched around a driving roller 22 and a driven roller 23, and is configured to attract and convey a sheet by electrostatic force or the like.

The shafts of the driving roller 22 and the driven roller 23 are rotatably supported by side plates 24 and 25 fixed to the main body of the apparatus. A gear 26 is fixed on the shaft of the drive roller 22 near the side plate 24, and the gear 26 is meshed with a gear 28 fixed to the motor shaft of the conveyor belt motor 27.

The conveyor belt motor 27 is composed of, for example, a pulse motor, and the drive roller 22 is provided via gears 28 and 26.
The drive roller 22 is rotated by rotationally driving the shaft of, and the transport belt 21 is rotationally driven.

Further, the conveyor belt 2 with respect to the paper conveying direction.
A sheet feeding system 211 (FIG. 1) is arranged outside the drawing on the upstream side of 1, while a sheet discharging system 212 (FIG. 1) is arranged outside the drawing on the downstream side.

Then, the paper P is the paper feeding system 211 (FIG. 1).
Is conveyed to the conveyance belt 21 by the ink, and while being conveyed by the conveyance belt 21, ink droplets are ejected from the nozzles 11 of each head unit for printing, and after the printing is completed, the paper is discharged to the outside of the apparatus main body by the paper ejection system 212 (FIG. 1) Is discharged.

FIG. 1 is a block diagram showing the control arrangement of an embodiment of an ink jet recording apparatus according to the present invention. In the present embodiment, the head carriage 1, the paper transport unit 2, the operation unit 3, the display unit 4, the control unit 5, and the like are included, and based on operation data and print data input from an external device such as a personal computer or an image reading device. The operation of each unit is performed.

Each head unit 1 of the head carriage 1
Y, 1M, 1C, and 1B are piezoelectric elements 15Y, 15M, 15C, and 15B that pressurize the pressure chambers, and drive circuits 16Y, 16M, and 16 that drive the corresponding piezoelectric elements, respectively.
It is equipped with C and 16B.

Piezoelectric elements 15Y, 15M, 15C, 15B
Is made of, for example, PZT, and is disposed on one side wall of the pressurizing chamber corresponding to each nozzle. A pair of electrodes is disposed on each side of the pressurizing chamber. It pressurizes the chamber.

Driving circuits 16Y, 16M, 16C, 16B
Is composed of a power source, various circuit elements, and the like, and applies a voltage signal between the electrodes of the corresponding piezoelectric element to deform the piezoelectric element. Further, each drive circuit is arranged in a proper place in each corresponding head unit and has a latch portion, which temporarily latches input serial binary or multi-valued print data for one line of paper, for example. It is converted into a signal and output.

Then, the ink droplets filled from the ink liquid chamber are ejected from the nozzles of each head unit toward the paper by the pressurization of the pressure chamber.

The paper transport unit 2 includes a transport belt motor 27,
It comprises a paper feed system 211, a paper discharge system 212, a drive circuit 213 and the like. The drive circuit 213 is composed of a power source, various circuit elements, and the like, and supplies a drive current to the conveyor belt motor 27, the paper feed system 211, and the paper discharge system 212. Driving and stopping are controlled by the controller 5.

The operation unit 3 includes a start key for starting the printing operation, a number setting key for setting the number of printed sheets, and the like, and is operated by the user. The display unit 4 is composed of an LED, an LCD or the like, and displays the set number of prints, the size of the printed paper, and the like.

The control unit 5 comprises a CPU 51, a storage unit 52, an interface (I / F) unit 53, etc.
The operation of the entire apparatus is controlled in synchronization with the internal clock 1. The CPU 51 includes a recording control unit 511, a mechanism control unit 512, a display control unit 513, and the like, and the recording control unit 511 and the mechanism control unit 512 perform control operations in synchronization with each other. The display control unit 513 controls the display content of the display unit 4.

The storage unit 52 is a ROM for storing control programs and fixed data, and an R for temporarily storing data and the like.
AM.

The I / F unit 53 receives a signal input from an external device, and print data is recorded in the recording control unit 511.
In addition, operation data such as paper size is output to the mechanism control unit 512.

The recording control unit 511 determines the piezoelectric element of the nozzle corresponding to the input print data based on the data regarding the used nozzle stored in the data storage unit 12, and also determines the print data of the head carriage 1. The signal is serially transmitted to the drive circuit corresponding to the nozzle, and the parallel signal converted by each drive circuit is output to the corresponding piezoelectric element as a pulse drive signal.

Further, when the input print data is color, the recording control section 511 outputs a drive signal to a necessary drive circuit among the drive circuits 16Y, 16M, 16C and 16B according to the color data. Output.

Further, the recording control section 511 has the distances d1 and d between the head units stored in the data storage section 12.
2, d3 (FIG. 3), according to a predetermined paper transport speed described later by the mechanism control unit 512,
Head units 1M and 1 for head unit 1Y
The ejection timing of ink droplets from the C and 1B nozzles is controlled.

The cycle of ink droplet ejection by the recording controller 511, that is, the cycle of signal output to each piezoelectric element is
It is set within the capability of the piezoelectric element.

The mechanism control section 512 drives the sheet feeding system 211 via the drive circuit 213 based on the input operation data to convey the sheet to the conveying belt 21. Further, the mechanism control unit 512 drives the paper discharge system 212 to discharge the printed paper to the outside of the apparatus main body.

Further, the mechanism control section 512 has the drive circuit 21.
A drive pulse is supplied to the conveyance belt motor 27 via 3 to drive the motor, and the paper is conveyed at a predetermined paper conveyance speed set according to the cycle of ink droplet ejection.

As described above, the recording control section 51 is based on the information stored in the data storage section 12 of the head carriage 1.
Since the ink droplet ejection control is performed by the method 1, high quality printing can be performed.

Even when the head carriage 1 provided in the recording apparatus is replaced, the data storage unit 12 for storing information about the head carriage 1 is provided in each head carriage 1, so that the replaced head is replaced. Control according to the carriage 1 can be performed, and similarly high printing quality can be maintained without causing color misregistration.

The information relating to the positional relationship between the head units stored in the data storage unit 12 is the head units 1M, 1 for the head unit 1Y as described above.
The same effect can be obtained even if the correction amount for the set distance is stored without being limited to the C and 1B distances.

If each head unit has a defective ejection nozzle that does not eject an ink droplet, the data storage unit 12 may store the position of the defective nozzle.

Further, the data storage unit 12 is, for example, EEP.
A rewritable memory element such as a ROM or a flash memory may be used. In this case, it is possible to maintain high print quality by rewriting the stored contents of the data storage unit 12 in accordance with changes in information regarding the head carriage 1, such as when a defective nozzle occurs during use of the apparatus. You can

Further, when the defective storage nozzle position is stored in the data storage unit 12, and when it is necessary to eject an ink droplet from the defective nozzle according to the print data, the recording control unit 511 causes both sides to perform ejection. Ink droplets may be ejected from one of the nozzles adjacent to. As a result, the positions of the ink dots ejected on the paper are slightly displaced, but the ejection failure can be made inconspicuous.

The data storage section 12 may be composed of a required number of DIP switches. In this case, it is possible to indicate the distance between the head units, the number of each end of the used nozzle from each end of the array nozzle, and the like by a binary number obtained by turning on and off each dip switch.

Further, the head carriage 1 is provided with a bar code for displaying the above-mentioned data as the data storage section 12.
The same effect can be obtained by disposing the bar code reading device including an optical sensor or the like on the apparatus main body side and sending the information read by this reading device to the recording control unit 511.

The head units 1Y, 1M, 1C,
1B may have a plurality of nozzles arranged as shown in FIG. The head units 1Y, 1M, 1C of FIG.
In 1B, five nozzle rows are arranged side by side, and each nozzle row has a required number of, for example, 1,000 nozzles 11 arranged in one direction at regular intervals D, and each nozzle row is parallel. The interval is a predetermined interval D ', and the nozzles 11 in each row are arranged so as to be sequentially shifted by D / 5.

By using such a head unit, the resolution in the nozzle arranging direction can be improved as compared with the nozzle arranging interval, but this configuration enlarges the size of the head carriage. Therefore, the distances d1, d2, d3 between the head units become relatively large, and if the accuracy in managing these distances is low, the print quality will be adversely affected. However, according to the present embodiment, data storage Since the unit 12 is provided, high print quality can be maintained.

[0054]

As described above, according to the first and second aspects of the present invention, the head unit in which the nozzles for ejecting ink droplets are arranged in a line, and the storage means for storing the characteristic information about this head unit. Therefore, when assembling the apparatus or exchanging the recording head, the characteristic information regarding the head unit is input to the apparatus main body side, and it is not necessary to input the characteristic information again, and the workability can be improved.

According to the third aspect of the invention, the characteristic information stored in the storage means is fetched and the fetched characteristic information is used to control the ink droplet ejection from the nozzle to the recording medium. High quality printing can be done on top. Further, even when the recording head arranged in the apparatus is replaced, since the storage means for storing the characteristic information regarding the head unit is arranged in each recording head, the control according to the replaced recording head should be performed. Similarly, high print quality can be maintained without causing color misregistration.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control configuration of an embodiment of an inkjet recording apparatus according to the present invention.

FIG. 2 is a perspective view showing a configuration of a head carriage used in the same embodiment.

FIG. 3 is a partial front view showing a part of the nozzle surface of the head carriage.

FIG. 4 is a perspective view showing a configuration around a print position in an embodiment of the inkjet recording apparatus according to the present invention.

FIG. 5 is a plan view showing a configuration example in which the nozzle arrangement of the head unit is different.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 head carriage (recording head) 1Y, 1M, 1C, 1B head unit 12 data storage section (storage means) 15Y, 15M, 15C, 15B piezoelectric element 16Y, 16M, 16C, 16B drive circuit 2 paper transport section 27 transport belt motor 3 Operation part 4 Display part 5 Control part 51 CPU 511 Recording control part (take-in means, discharge control means) 512 Mechanism control part 52 Storage part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kikunosuke Tsuji 1-228 Tamatsukuri, Chuo-ku, Osaka Mita Engineering Co., Ltd. (72) Takeshi Watanabe 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Within Kogyo Co., Ltd.

Claims (3)

[Claims] 1. A recording head comprising a head unit in which nozzles for ejecting ink droplets are arranged in a line, and a storage unit for storing characteristic information regarding the head unit. 2. The recording head comprises a plurality of head units arranged at predetermined positions, and the storage means stores the positional relationship between the head units as characteristic information. The recording head according to claim 1. 3. The recording head according to claim 1 or 2,
Inkjet recording comprising: a capturing unit that captures the characteristic information stored in the storage unit; and an ejection control unit that controls the ejection of ink droplets from the nozzle to the recording medium using the captured characteristic information. apparatus.