JP2004299064A - Image recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the quality of recording images corresponding to an overlapping recording part of adjacent head modules. <P>SOLUTION: At the time of recording data corresponding to the overlapping recording part of each head module to a recording medium, it is judged whether or not the data can be recorded by either one of two adjacent head modules. When it is judged that recording by either one of the head modules is possible, the data is recorded by the one head module. When it is judged that recording by either of the head modules is impossible, the data is recorded by both of the head modules. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image recording apparatus that has a head unit that extends in a direction substantially perpendicular to a recording medium feeding direction and that discharges ink toward the recording medium.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as an image recording apparatus of this type, a so-called line head type having a plurality of head units extending in a direction substantially perpendicular to a recording medium feed direction and ejecting ink toward the recording medium has been known. (See Patent Document 1). In an image recording apparatus for color printing, four head units are arranged in the feed direction of a recording medium, and each head unit ejects black, cyan, magenta, and yellow inks, respectively.
[0003]
Each head unit has a plurality of head modules arranged side by side in the longitudinal direction of the head unit. The head modules extend in the longitudinal direction of the head unit, and are arranged side by side in the longitudinal direction of the head unit so as to be staggered at predetermined intervals in the feeding direction of the recording medium. Thus, when a defect such as a defective ink discharge occurs in a part of the head unit, the defect is eliminated by replacing the defective head module. That is, when each head unit is composed of one module, it is not necessary to replace all the head units when a defect such as an ink ejection failure occurs in a part of the head, and the maintenance is excellent. ing.
[0004]
Each head module overlaps an adjacent head module at an end in the longitudinal direction, and recording can be performed on this portion using any of the head modules. At the overlapping recording portion in each head module, recording is performed by the head module located on the upstream side in the feed direction of the recording medium.
[0005]
[Patent Document 1]
JP-A-58-63454.
[Problems to be solved by the invention]
By the way, in the image recording apparatus, when data is recorded on the recording medium at the overlapping recording portion, part of the data is recorded by the head module on the upstream side, and the other part is recorded on the head module on the downstream side. That is, the recorded data has a joint portion between a part and another portion where ink is ejected by separate head modules.
[0007]
Here, as described above, since each head module can be replaced independently or the like, there is a possibility that each head module cannot be attached to a desired set position with high accuracy. That is, if the relative mounting positions of the head modules are shifted, a joint portion of the recorded image is visually recognized, and there is a possibility that the quality of the recorded image on the recording medium may be deteriorated. Further, when ink is ejected from all nozzles of the same head module row, there may be a difference in ink ejection performance at the end of the same row due to the influence of ink flow. Due to such a phenomenon, the joint portion of the recorded image is visually recognized, which is a factor of deteriorating the recording quality of the recording medium.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image recording apparatus capable of improving the quality of a recorded image corresponding to an overlapping recording portion of an adjacent head module. It is in.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, in the invention according to claim 1,
A head unit that extends in a direction substantially perpendicular to the feeding direction of the recording medium and that discharges ink toward the recording medium;
The head unit has a plurality of head modules that are arranged in parallel in the longitudinal direction of the head unit so as to be staggered at predetermined intervals in the feed direction and extend in the longitudinal direction of the head unit,
In the image recording apparatus, each of the plurality of head modules has an overlapping recording portion that overlaps an adjacent head module in a longitudinal direction.
When recording data corresponding to the overlapping recording portion on the recording medium, determining means for determining whether the data can be recorded by one of two adjacent head modules,
If it is determined by the determining means that the recording can be performed by one of the head modules, the data is recorded by the one head module, and the recording cannot be performed by the one of the head modules by the determining means. Recording control means for recording the data by both head modules when it is determined that
[0010]
According to the first aspect of the present invention, when data corresponding to the overlapping recording portion of each head module is recorded on the recording medium, the data may be recorded by one of two adjacent head modules by the judging means. It is determined whether or not it is possible. Here, when it is determined by the determining means that recording can be performed by one of the head modules, the data is recorded on the recording medium by the one head module.
[0011]
In this case, even if the data corresponds to the overlapping recording portion, it is recorded by one head module, so that the recorded image does not have a seam. Therefore, when the ink ejection state is different between adjacent head modules, even when the relative mounting position of each head module is shifted, the recorded image does not become non-uniform, etc. Since data is recorded by one head module, the quality of a recorded image on a recording medium can be improved.
[0012]
If the determination means determines that recording by one of the head modules is not possible, data recording is performed by both head modules as in the related art.
[0013]
According to a second aspect of the present invention, in the image recording apparatus according to the first aspect, when the data is character data, one of the heads is determined based on the number of points of the character data. It is characterized in that it is determined whether or not recording by a module is possible.
[0014]
According to the second aspect of the present invention, in addition to the operation of the first aspect, when the data corresponding to the overlapping recording portion of each head module is character data, whether or not recording by one of the head modules is possible. This is determined based on the number of points indicating the size of the character data, so that this determination control can be performed easily and easily. That is, for example, the determination can be made by a simple algorithm or the like that compares the size of the overlapping recording portion with the size of the character data. Therefore, the quality of the recorded image on the recording medium can be improved with simple control, which is extremely advantageous in practical use.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
1 to 5 show an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of an image recording apparatus, FIG. 2 is a schematic top view showing a positional relationship of each head unit, and FIG. FIG. 4 is a schematic top view showing an overlap recording portion, FIG. 4 is a block diagram showing a main control portion of the image recording apparatus, and FIG. 5 is a block diagram showing a configuration of the image recording section.
[0016]
As shown in FIG. 1, the image recording apparatus 1 is provided with a storage tray 3 for storing a plurality of recording media 2 in a stacked manner below an inside of a device main body 1a formed in a substantially box shape. At the upper end of one end of the storage tray 3, a take-out device 4 for taking out the recording medium 2 on which an image is to be recorded one by one from the storage tray 3 is provided. The recording medium 2 may be paper such as plain paper, recycled paper, glossy paper, or the like, or may be a cut sheet made of a material such as cloth, resin, metal, or glass. A transport device 5 that transports the recording medium 2 is disposed above the storage tray 3.
[0017]
In the transport device 5, an annular transport belt 51 that supports the recording medium 2 in a planar shape and transports the recording medium 2 in a horizontal direction is movably stretched by a plurality of stretching rollers 52. That is, the upper surface of the transport belt 51 is stretched so as to be horizontal. Further, the transport device 5 is provided with a pressing roller 53 that presses against the transport belt 51 to transport the recording medium 2 in a planar manner at a position where the transport belt 51 and the recording medium 2 start to contact with each other. Have been.
[0018]
As shown in FIG. 1, black (Bk), cyan (C), magenta (M), and yellow (Y) inks are sequentially provided in the vicinity of the upper portion of the transport belt 51 from the upstream side along the feeding direction. Head units 11, 12, 13, and 14 provided with nozzles that discharge toward the recording medium 2 are provided so as to extend in the width direction of the transport belt 51. The recording medium 2 on which an image is recorded by each of the head units 11, 12, 13, and 14 is sequentially discharged to a discharge tray 6 on the side of the apparatus main body 1a.
[0019]
As shown in FIG. 2, each of the head units 11, 12, 13, and 14 extends in a direction substantially orthogonal to the recording medium feed direction. Each of the head units 11, 12, 13, and 14 has a plurality of head modules 11a, 12a, 13a, and 14a arranged in parallel in the longitudinal direction of the head units 11, 12, 13, and 14. The head modules 11a, 12a, 13a, and 14a extend in the longitudinal direction of the head units 11, 12, 13, and 14, and are alternately arranged at predetermined intervals in the feeding direction of the recording medium 2. 13 and 14 are juxtaposed in the longitudinal direction.
[0020]
FIG. 3 is a partially enlarged view of the black head unit 11. Each head module 11a has an overlapping recording portion 11b that overlaps the adjacent head module 11a in the longitudinal direction. Each head module 11a is provided with a plurality of nozzles 11c for ejecting ink at predetermined intervals in the longitudinal direction. As shown in FIG. 3, the longitudinal positions of the nozzles 11 c are substantially located at each overlapping recording portion 11 b. That is, in the overlapping recording portion 11b, the same image recording can be performed using the upstream head module 11a or the downstream head module 11a. The cyan, magenta, and yellow head units 12, 13, and 14 also have the same configuration.
[0021]
As shown in FIG. 4, the image recording device 1 includes a control device for controlling the device. The control device includes a control unit 20 including, for example, a CPU, a ROM, and a RAM (all not shown). The control unit 20 expands the processing program stored in the ROM into the RAM and executes the processing program by the CPU.
[0022]
The control unit 20 receives an image data input / output interface (I / F) 21 for receiving image information sent to the image recording apparatus, compresses and stores the transferred image data in page units, and further stores the compressed image data. And a compression / decompression unit 22 for decompressing and storing. Further, the control unit 20 includes an operation unit 23 for the user to perform input operations such as the number of copies and the number of copies, an image processing unit 24 for converting the obtained image data so as to be adapted to an image output format, and an image processing unit 24. And an image recording signal output I / F 25 for outputting the image data converted in step (1) to the image recording unit 31 of the image recording unit 30. Further, the control unit 20 captures an image obtained by photographing with an imaging device such as a digital camera or image data read by another reading device, or records an image by an instruction from an external device. F26 and a print controller 27. Further, the control unit 20 controls the operation of the image processing unit 24, the image recording signal output I / F 25, the external I / F 26, and the print controller 27 in accordance with the operation unit 23 and the image information. 28.
[0023]
As shown in FIG. 4, the image recording unit 30 serving as a determination unit and a recording control unit includes an image recording unit 31 that performs image recording according to a signal from an image recording signal output I / F 25, and an extending roller 52. A transport mechanism 32 for controlling the image forming apparatus, an image recording control unit (S-CPU) 33 for controlling these operations, and a ROM 34 are provided. The image recording control unit 33 controls the operations of the image recording unit 31 and the transport mechanism 32 based on a program stored in the ROM 34.
[0024]
When data corresponding to the overlapping recording portions 11b, 12b, 13b, 14b of the head modules 11a, 12a, 13a, 14a is recorded on the recording medium 2, the ROM 34 stores the data in two adjacent head modules 11a, 12a, 13a, 14a. A determination program 34a for determining whether recording can be performed by any one of 12a, 13a, and 14a is stored. In the present embodiment, the determination program 34a makes the above-described determination only for text-type character data. In the present embodiment, the above-described determination is made based on the number of points of the character data.
[0025]
When the determination program 34a determines that the recording can be performed by one of the head modules 11a, 12a, 13a, and 14a, the ROM 34 stores the data of the one head module 11a, 12a, 13a, and 14a. Recording is performed, and if it is determined by the determination program 34a that recording by any one of the head modules 11a, 12a, 13a, and 14a is impossible, data recording by both head modules 11a, 12a, 13a, and 14a is performed. A recording control program 34b for performing is stored.
[0026]
As shown in FIG. 5, the image recording unit 31 controls a plurality of buffer memories provided for each color to store each color signal sent from the image recording signal output I / F 25 and outputs from each buffer memory. A color signal memory 35 comprising a buffer memory control circuit; a head unit drive circuit 36 for driving and controlling the ink discharge operation of the head units 11, 12, 13, and 14 based on the color signal output under the control of the buffer memory control circuit. Etc.
[0027]
In the image recording apparatus 1 configured as described above, when the image information is sent from the host computer or the like, the image information is sent to the overall control unit 28 and the image data input / output I / F 21 to the image processing unit 24. Sent. The image information is also sent from the host computer or the like to the overall control unit 28 via the external I / F 26 and the print controller 27.
[0028]
The general control unit 28 starts the operation of each component of the control unit 20 when the image information is transmitted. The operation start timing is not limited to when image information is input, but may be an operation input from the operation unit 23 or an operation input from a host computer or the like via the external I / F 26 and the print controller 27. It may be when.
[0029]
The image processing unit 24 performs image processing so that the image information is adapted to the image output format. Image data composed of color signals separated for each color by image processing is sent from the image recording signal output I / F 25 to the image recording unit 31 of the image recording unit 30.
[0030]
The image information before image processing can be sent from the image data input / output I / F 21 to the compression / decompression unit 22 and stored. Here, the compression / decompression unit 22 receives an operation input from the host computer or the like via the external I / F 26 and the print controller 27, not only when image data is sent from the image processing unit 24. It may be made to work sometimes.
[0031]
When the image information is sent to the image recording device 1, the image recording control unit 33 of the image recording unit 30 controls the transport mechanism 32 and the like based on each color signal stored in the color signal memory 35 of the image recording unit 31. Let it work. Along with this operation, the head unit drive circuit 36 operates the head units 11, 12, 13, and 14. Specifically, the transport mechanism 32 operates the take-out device 4 to take out the uppermost recording medium 2 stored in the storage tray 3 and transport the recording medium 2.
[0032]
When the leading end of the recording medium 2 reaches the transport belt 51, the pressing roller 53 presses the leading end of the recording medium 2 against the peripheral surface of the transport belt 51, whereby the recording medium 2 is held. The recording medium 2 moves together with the transport belt 51 by the rotation of the stretching roller 52, and is transported in the horizontal direction. When the recording medium 2 is sent to the position of the head unit 11, black ink is ejected from each head module 11a onto the recording medium 2.
[0033]
Here, when the character data corresponding to the overlapping recording portion 11b of each head module 11a is recorded on the recording medium 2, the determination program 34a is activated and recorded by one of the two adjacent head modules 11a. It is determined whether or not it is possible. In the present embodiment, as described above, the determination is made based on the number of points of the character data. For example, if the length in the longitudinal direction of the overlapping recording portion 11b is approximately 5 points in terms of the number of points, it may be determined that character data of 4 points or less can be recorded by one head module 11a. Good.
[0034]
When it is determined that recording can be performed by one head module 11a, character data is recorded on the recording medium 2 by one head module 11a. If it is determined that recording cannot be performed by one of the head modules 11a, character data is recorded by both head modules 11a.
[0035]
After the black ink data recording in the head unit 11 is completed, the cyan unit data recording, the magenta ink data recording in the head unit 13, and the yellow ink data recording in the head unit 14 are performed in the same procedure. .
[0036]
As described above, according to the image recording apparatus 1 of the present embodiment, even the character data corresponding to the overlapping recording portions 11b, 12b, 13b, and 14b are recorded by one of the head modules 11a, 12a, 13a, and 14a. Therefore, no seam occurs in the recorded image. Therefore, when the ink ejection state is different between the adjacent head modules 11a, 12a, 13a, 14a, or when the relative mounting positions of the head modules 11a, 12a, 13a, 14a are shifted. However, since the recorded image does not become non-uniform and the data is recorded by one head module 11a, 12a, 13a, 14a, the quality of the recorded image on the recording medium can be improved. If recording cannot be performed by one of the head modules 11a, 12a, 13a, and 14a, the data is recorded by the two head modules 11a, 12a, 13a, and 14a. Does not occur.
[0037]
Further, according to the image recording apparatus 1 of the present embodiment, whether or not the recording can be performed by one of the head modules 11a, 12a, 13a, and 14a is determined based on the number of points indicating the size of the character data. Therefore, this determination control can be easily and easily performed. That is, for example, the determination can be made by a simple algorithm or the like that compares the size of the overlapping recording portions 11b, 12b, 13b, and 14b with the size of the character data. Therefore, it is possible to prevent the quality of the recorded image on the recording medium 2 from being reduced by simple control, which is extremely advantageous in practical use.
[0038]
In the above-described embodiment, the determination is made as to whether or not the recording can be performed by only one of the head modules 11a, 12a, 13a, and 14a only with respect to the character data. It may be. Even in this case, it is preferable to determine the character data based on the number of points.
[0039]
In the above embodiment, the image recording unit 30 determines whether or not the recording can be performed by one of the head modules 11a, 12a, 13a, and 14a, but the control unit 20 determines. Needless to say, the configuration may be adopted.
[0040]
In the above-described embodiment, the four head units 11, 12, 13, and 14 are provided and a color image is recorded on the recording medium 2. However, an image is recorded on the recording medium by one head unit. It goes without saying that other specific structures and the like can be appropriately changed.
[0041]
【The invention's effect】
As described in detail above, according to the first aspect of the present invention,
When recording can be performed by one head module, data corresponding to the overlapping recording portion is recorded by one head module, so that the recorded image does not become uneven and the quality of the recorded image on the recording medium is not increased. Can be improved. Further, when recording cannot be performed by one head module, data is recorded by two head modules, so that there is no problem in recording data on a recording medium.
[0042]
According to the invention described in claim 2, in addition to the effect of claim 1,
Whether the recording by one of the head modules is possible or not is determined based on the number of points indicating the size of the character data. Therefore, it is possible to prevent the quality of the recorded image on the recording medium from deteriorating by simple control. This is extremely advantageous in practical use.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an image recording apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic top view showing a positional relationship between head units.
FIG. 3 is a schematic top view showing an overlap recording portion of each head module.
FIG. 4 is a block diagram illustrating a main control portion of the image recording apparatus.
FIG. 5 is a block diagram illustrating a configuration of an image recording unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image recording apparatus 2 Recording medium 11 Head unit 11a Head module 11b Duplicate recording part 12 Head unit 12a Head module 12b Duplicate recording part 13 Head unit 13a Head module 13b Duplicate recording part 14 Head unit 14a Head module 14b Duplicate recording part 30 Image recording Unit 33 image recording controller 34 ROM
34a determination program 34b recording control program

Claims (2)

A head unit that extends in a direction substantially perpendicular to the feeding direction of the recording medium and that discharges ink toward the recording medium;
The head unit has a plurality of head modules that are arranged in parallel in the longitudinal direction of the head unit so as to be staggered at predetermined intervals in the feed direction and extend in the longitudinal direction of the head unit,
In the image recording apparatus, each of the plurality of head modules has an overlapping recording portion that overlaps an adjacent head module in a longitudinal direction.
When recording data corresponding to the overlapping recording portion on the recording medium, determining means for determining whether the data can be recorded by one of two adjacent head modules,
If it is determined by the determining means that the recording can be performed by one of the head modules, the data is recorded by the one head module, and the recording cannot be performed by the one of the head modules by the determining means. Recording control means for performing recording of the data by both head modules when it is determined that The said determination means, when the data is character data, determines whether or not recording by any one of the head modules is possible based on the number of points of the character data. 2. The image recording device according to 1.

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