JP2020116896A - Ink jet printer - Google Patents

Abstract

To provide an ink jet printer that performs normal printing even if a control board and respective ink jet heads are wired incorrectly.SOLUTION: An ink jet printer comprises: a head connection information storage part which is previously stored with head connection information in which respective connectors 100 of a control board 60 and identification information on respective ink jet heads 34 connected to the respective connectors 100 are made to correspond to each other; and a determination part 91a which acquires identification information on the ink jet head 34 connected to each connector 100 and determines whether the identification information is different from the head connection information. If it is determined that identification information on an ink jet head 34 is different from the head connection information and the connector 100 as a connection destination of a data line 101 connected to the ink jet head 34 whose identification information is different from the head connection information is wrong, a head control circuit 84 switches control data to be output to the connector 100 so that correct control data is output to the ink jet head 34.SELECTED DRAWING: Figure 4

Description

The present invention relates to an inkjet printing device including a plurality of inkjet heads.

Conventionally, there has been proposed an inkjet printing apparatus that performs a printing process by ejecting ink from an inkjet head onto a print medium that is transported on a transport path.

As such an ink jet printing apparatus, a line type ink jet printing apparatus has been proposed in which a plurality of ink jet heads are arranged in a direction orthogonal to the transport direction of a print medium, and the plurality of ink jet heads perform printing for one line. ..

In the line-type inkjet printing apparatus, since a line head including a plurality of inkjet heads is provided for each color of ink, a large number of inkjet heads are installed.

JP, 2008-100471, A JP, 2016-159453, A

Here, in a line-type inkjet printing apparatus including a large number of inkjet heads as described above, there are a large number of wirings that connect each inkjet head with a control board that controls the inkjet head, and ink is supplied to each inkjet head. Since there is also an ink path to do so, physical structures are crowded in the device, and it is very difficult to accurately wire.

In addition, the inkjet head is located in the center of the device and is accessed only during heavy maintenance such as replacement of the inkjet head.Therefore, the inkjet head is not easily accessible. In that case, it takes some man-hours to access the inkjet head again. Although it is conceivable to add a mark to each wiring, the number of man-hours in the manufacturing process is required, which increases the cost.

Note that Japanese Patent Application Laid-Open No. 2004-242242 proposes that an ink cartridge is provided with a storage element such as a semiconductor memory, and the storage element stores an identification ID for identifying an ink color and an ink remaining amount. No proposal has been made regarding the wiring error between the control board and each ink cartridge as described above.

Further, in Japanese Patent Laid-Open No. 2004-242242, when there is an error in the wiring between the main board that outputs a control signal to the drive circuit of each inkjet head and the sub-board on which the drive circuit of each inkjet head is provided, It has been proposed that the main board output a correct control signal to the sub-board by switching the wiring state of the programmable logic circuit unit provided on the board.

However, in Patent Document 2, the output of the inquiry signal from the main board to the sub board and the output of the identification signal from the sub board to the main board according to the inquiry signal are repeated while switching the wiring state of the programmable logic circuit unit. It is necessary to carry out this process, which complicates the signal processing and the circuit configuration, and incurs cost.

In view of the above circumstances, the present invention performs normal printing by a simple process and a circuit configuration even when the wiring between the control board and each inkjet head is erroneous when the inkjet head or the control board is replaced. It is an object of the present invention to provide an inkjet printing device that can perform the above.

The inkjet printing apparatus of the present invention includes a plurality of inkjet heads for ejecting ink onto a print medium, a plurality of connectors, and a control board having a head control circuit for supplying control data for each inkjet head to each connector, and each inkjet head. One end is connected to the head, the other end is connected to each connector, and a plurality of data lines that respectively supply the control data output from each connector to each inkjet head, and each connector and each connector Is connected to each connector via a data line, and a head connection information storage unit in which head connection information associated with identification information of each inkjet head connected via a data line is stored in advance. And a determination unit that determines whether or not the identification information of each inkjet head is different from the head connection information, and the head control circuit causes the determination unit to determine the identification information of at least two inkjet heads different from the head connection information. If the connector of the connection destination of the data line connected to the inkjet head of the identification information different from the head connection information is incorrect, the correct control data for the inkjet head of the identification information different from the head connection information is detected. The control data output to the connector is switched so that is output.

According to the inkjet printing apparatus of the present invention, the head connection information in which each connector of the control board and the identification information of each inkjet head connected to the connector via the data line are associated with each other is stored in advance. Then, the identification information of each inkjet head connected to each connector via the data line is acquired, and it is determined whether the identification information is different from the head connection information. When it is determined that the identification information of at least two inkjet heads is different from the head connection information, and the connector of the connection destination of the data line connected to the inkjet head of the identification information different from the head connection information is incorrect, The control data output to the connector is switched so that the correct control data is output to the inkjet head having the identification information different from the head connection information.

Thus, even when the wiring between the control board and each inkjet head is erroneous when the inkjet head or the control board is replaced, normal printing can be performed by a simple process and a circuit configuration.

The figure which shows the schematic structure of one Embodiment of the inkjet printing apparatus of this invention. Head unit top view Block diagram showing a schematic configuration of a control system of the inkjet printing apparatus shown in FIG. Diagram showing an example of the hardware configuration of the control board Diagram showing a schematic configuration of a head control circuit Diagram showing an example of head connection information Diagram showing the printing result when the data line of the inkjet head is correctly connected to the connector of the control board The figure which shows the printing result when the data line of the inkjet head is mistakenly connected to the connector of the control board. Diagram showing an example of the test pattern Flowchart for explaining the operation of the inkjet printing apparatus shown in FIG. The figure which shows schematic structure of other embodiment of the inkjet printing apparatus of this invention. Diagram showing other examples of test patterns Diagram showing other examples of test patterns

Hereinafter, an embodiment of an inkjet printing apparatus of the present invention will be described in detail with reference to the drawings. The inkjet printing apparatus according to the present embodiment is characterized by a method for correcting a wiring error in the data line of the inkjet head. First, the overall configuration will be described. FIG. 1 is a diagram showing a schematic configuration of an inkjet printing apparatus 1 of this embodiment. The up, down, left, and right directions shown in FIG. 1 are the up, down, left, and right directions of the inkjet printing apparatus 1 of this embodiment. Further, the front side of the paper of FIG. 1 is the front direction, and the back side of the paper is the back direction.

As shown in FIG. 1, the inkjet printing apparatus 1 of the present embodiment includes a side paper feed unit 10, an internal paper feed unit 20, a print processing unit 30, a paper discharge unit 40, a reversing unit 50, and a control board. 60 and an operation panel 70.

The print processing unit 30, the internal paper feeding unit 20, and the control board 60 are housed and installed in a housing formed of metal or resin. In addition, the side paper feed unit 10, the paper discharge unit 40, and the reversing unit 50 are installed in a state where a part of the side paper feed unit 10, the paper discharge unit 40, and the reversing unit 50 are housed inside the housing and part of the housing protrudes outside the housing.

The side paper feed section 10 is a paper feed tray 11 on which the print medium P is placed, and a primary paper feed section that feeds out only the uppermost print medium P from the paper feed tray 11 and conveys it onto the paper feed conveyance path FR. 12 and a secondary paper feeding unit 14 that carries the print medium P carried by the primary paper feeding unit 12 onto the circulation carrying path CR.

The internal paper feed unit 20 is a primary paper feed unit 21a on which the print medium P is placed, and a primary paper feed unit that feeds out only the uppermost print medium P from the paper feed base 21a and conveys it onto the paper feed conveyance route FR. 22a, a paper feed table 21b on which the print medium P is placed, a primary paper feed section 22b for feeding only the uppermost print medium P from the paper feed table 21b and carrying it to the paper feed path FR, and printing The paper feed table 21c on which the medium P is placed, the primary paper feed section 22c for feeding out only the uppermost print medium P from the paper feed tray 21c and carrying it to the paper feed carrying path FR, and the print medium P are placed. It is provided with a paper feed table 21d to be placed and a primary paper feed section 22d for feeding out only the uppermost print medium P from the paper feed table 21d and carrying it to the paper feed path FR.

As described above, the print medium P is conveyed from the side paper feed unit 10 or the internal paper feed unit 20 to the secondary paper feed unit 14, and the print medium P is further carried from the reversing unit 50 described later.

Therefore, in front of the secondary paper feed unit 14 in the transport direction, the transport path of the print medium P fed from the internal paper feed unit 20 and the print medium P on which one surface transported from the reversing unit 50 is printed. There is a confluence point where the transportation route of the vehicle merges. A path on the paper feed mechanism side is referred to as a paper feed conveyance path FR, and other paths are referred to as a circulation conveyance path CR with reference to this joining point.

The print processing unit 30 includes a head unit 31 and an annular transport belt 133 provided so as to face the head unit 31.

The conveyor belt 133 is formed of an annular endless belt and has a large number of suction holes. The print medium P fed from the secondary paper feed unit 14 is conveyed to the circular conveyance belt 133. Then, the print medium P is adsorbed onto the conveyor belt 133 by the suction of the suction fans 131 and 132 installed on the back side of the conveyor road surface of the conveyor belt 133, and is conveyed at a predetermined conveying speed. Then, while the print medium P is being transported by the transport belt 133, ink is ejected from the head unit 31 to the print medium P, whereby the print processing is performed on the print medium P.

The head unit 31 includes four line heads 32a, 32b, 32c, 32d and a head holder 33 in which the four line heads 32a, 32b, 32c, 32d are installed.

Each of the line heads 32 a to 32 d extends in a direction orthogonal to the transport direction of the print medium P, and ejects ink onto the print medium P transported by the transport belt 133. As shown in FIG. 1, the four line heads 32a to 32d are arranged at predetermined intervals along the conveyance path of the print medium P. The line head 32a ejects black ink, the line head 32b ejects cyan ink, the line head 32c ejects magenta ink, and the line head 32d ejects yellow ink.

The head holder 33 is a member on which the inkjet head 34 included in each of the line heads 32a to 32d is installed. FIG. 2 is a top view of a state in which the inkjet head 34 of each of the line heads 32a to 32d is installed in the head holder 33 as seen from above.

The head holder 33 is composed of a box-shaped support member, and the bottom surface of the head holder 33 has a plurality of installation holes in which the inkjet heads 34 are fitted and installed. The installation hole is a through hole, and is formed so that the ink ejection surface of each inkjet head 34 is exposed outside the bottom surface of the head holder 33.

The dotted line rectangles shown in FIG. 2 indicate the ranges in which the six inkjet heads 34 of the line heads 32a to 32d are arranged.

As shown in FIG. 2, each of the line heads 32a to 32d has a head row in which three inkjet heads 34 are arranged at equal intervals in a direction (front-back direction) orthogonal to the transport direction of the print medium P. Each of the line heads 32a to 32d has two head rows, and the two head rows are arranged in a staggered manner so that the inkjet heads 34 of each head row overlap by a predetermined number of nozzles. Has been done.

Then, printing is performed by the inkjet heads 34 of the two rows of heads included in each of the line heads 32a to 32d to form a print image of one line.

Further, each inkjet head 34 of the present embodiment includes a storage unit 35 (see FIG. 4). The storage unit 35 includes a semiconductor memory and stores head identification information unique to each inkjet head 34 and head characteristic information of each inkjet head 34. In the present embodiment, information on the reference voltage value and the drive waveform of each inkjet head 34 is stored as the head characteristic information. Further, in the present embodiment, the storage unit 35 corresponds to the characteristic information storage unit of the present invention.

The print medium P that has been subjected to the print processing by the print processing unit 30 is conveyed on the circulation conveyance path CR by the conveyance rollers arranged on the circulation conveyance path CR. A switching mechanism 43 for switching between guiding the print medium P transported on the circulation transport route CR to the paper discharge unit 40 or recirculating on the circulation transport route CR is provided on the circulation transport route CR. There is. The switching mechanism 43 specifically switches between the transport path on the side of the paper discharge unit 40 and the transport path on the side of the reversing unit 50.

The paper discharge unit 40 includes a tray-shaped paper discharge base 41 protruding from the housing of the inkjet printing apparatus 1, and a pair of paper discharge rollers 42 that discharge the print medium P onto the paper discharge base 41. Then, the print medium P guided by the switching mechanism 43 to the transport path on the side of the paper discharge unit 40 is discharged onto the paper discharge tray 41 by the paper discharge rollers 42.

The reversing unit 50 conveys the print medium P from the circulation conveyance route CR to the reversal stage 51 and the reversal table 51 for reversing the print medium P, and transfers the print medium P conveyed to the reversal stage 51 on the circulation conveyance route CR. And a reversing roller 52 for returning to.

The print medium P guided to the reversing unit 50 by the switching mechanism 43 is conveyed by the reversing rollers 52 from the circulation conveyance path CR to the reversing table 51, and is returned from the reversing table 51 to the circulation conveyance path CR again so that the front and back are reversed. In this state, it is conveyed on the circulation conveyance route CR. Then, the print medium P whose front and back are reversed is again conveyed toward the print processing unit 30 by a plurality of rollers such as the conveyance roller 53 provided on the circulation conveyance path CR.

The operation panel 70 is composed of a touch panel having a liquid crystal display, displays various setting input screens, and receives various setting inputs such as a print start instruction input. In particular, in the operation panel 70 of the present embodiment, the data line 101 (see FIG. 4) connected to each inkjet head 34 is caused by the replacement of the inkjet head 34 or the control board 60, etc., and each connector 100 of the control board 60. When it is erroneously connected, the switching information of the control data output to each connector 100 is accepted. This switching information will be described later in detail.

The control board 60 controls the entire inkjet printing apparatus 1. FIG. 3 is a block diagram showing a schematic configuration of a control system of the inkjet printing apparatus 1 of this embodiment. The control board 60 includes a CPU (Central Processing Unit), a semiconductor memory, and the like, and controls the operation of each unit of the inkjet printing apparatus 1 by causing the CPU to execute a program stored in advance in the semiconductor memory.

FIG. 4 is a diagram illustrating a hardware configuration example of the control board 60. As shown in FIG. 4, the control board 60 includes a main controller 80, a mechanical controller 90, and a connector 100.

The main controller 80 mainly receives an input of a print job output from a computer or the like, separates the print job into image data to be printed and job data, and controls the inkjet head 34 based on the image data. .. The job data is data including information related to the transport control of the print medium P, such as the size and number of the print medium P.

The main controller 80 specifically includes a CPU 81, a memory 82, an image control circuit 83, a head control circuit 84, a mechanical controller I/F 85, a user I/F 86, and an external I/F 87. The CPU 81 controls the entire main controller 80, and the memory 82 stores programs for controlling various operations and various information.

The image control circuit 83 performs various image processes on the image data included in the print job. Examples of image processing include error diffusion processing and joint correction processing between adjacent inkjet heads 34. The image data subjected to the image processing in the image control circuit 83 is output to the head control circuit 84.

The head control circuit 84 generates control data based on the input image-processed image data, controls each inkjet head 34 based on the control data, and causes each inkjet head 34 to eject ink. Further, the head control circuit 84 controls the ink ejection timing from each inkjet head 34, the print start timing, the print end timing, and the like based on the control signal output from the mechanical controller 90.

Further, the head control circuit 84 switches the control data output to each connector 100 based on the switching information set and input by the user on the operation panel 70. The switching of the control data will be described later in detail.

A data line 101 that supplies control data to each inkjet head 34 is connected to the connector 100. Each inkjet head 34 is connected to one end of each data line 101, and each connector 100 is connected to the other end of each data line 101. The connectors 100 and the data lines 101 are provided in the same number as the inkjet heads 34, but they are omitted in FIG.

The mechanical controller I/F 85 mutually communicates with the main controller I/F 93 of the mechanical controller 90, and enables various information to be exchanged between the main controller 80 and the mechanical controller 90.

The user I/F 86 is connected to the operation panel 70 and acquires information set and input by the user on the operation panel 70.

The external I/F 87 is connected to, for example, a computer that outputs a print job, and acquires the print job output from the computer.

The mechanical controller 90 mainly acquires the job data output from the main controller 80, and controls an actuator such as a drive motor of the transport system based on the job data.

The mechanical controller 90 specifically includes a CPU 91, a memory 92, a main controller I/F 93, a sensor I/F 94, an actuator I/F 95, and an image control I/F 96. The CPU 91 controls the entire mechanical controller 90, and the memory 92 stores programs for controlling various operations and various information.

Further, the mechanical controller 90 acquires a detection signal of a paper detection sensor (not shown) that detects the print medium P via the sensor I/F 94, and based on the detection signal and job data, via the actuator I/F 95. Then, the control signal is output to the actuator of the transport system. Further, the mechanical controller 90 outputs a control signal to the image control circuit 83 and the head control circuit 84 of the main controller 80 via the image control I/F 96 to control the ink ejection timing from the inkjet head 34 and the like.

The main controller I/F 93 mutually communicates with the mechanical controller I/F 85 of the main controller 80, and enables various information to be exchanged between the mechanical controller 90 and the main controller 80.

Further, the mechanical controller 90 controls the head control circuit 84 based on the switching information set and input by the user on the operation panel 70 to switch the control data output to each connector 100. The circuit configuration for switching the control data output to each connector 100 will be described below. FIG. 5 is a diagram showing a schematic configuration of the head control circuit 84. In order to make the explanation easy to understand, FIG. 5 shows a circuit configuration for switching control data output to the two connectors 100 (connector 1 and connector 2).

As shown in FIG. 5, the head control circuit 84 includes a read circuit 201, a head connection information storage unit 202, a MUX 203 for connector 1, a MUX 204 for connector 2, a characteristic information register 205 for connector 1, a characteristic information register 206 for connector 2, A connector 1 voltage generation circuit 207 and a connector 2 voltage generation circuit 208 are provided.

The readout circuit 201 reads out the head identification information and the head characteristic information stored in the storage unit 35 of each inkjet head 34, and outputs them to the mechanical controller 90 via the mechanical controller I/F 85 and the main controller I/F 93.

The head connection information storage unit 202 includes a semiconductor memory and associates each connector 100 with the head identification information of each inkjet head 34 connected to each connector 100 via the data line 101. Memorize In the present embodiment, as shown in FIG. 6, a table in which the numbers C1 to C24 of each connector 100 and the head identification information ID1 to ID24 of each inkjet head 34 are associated is stored as head connection information. ..

In the present embodiment, after each inkjet head 34 is attached to the head holder 33, each data line 101 connected to each inkjet head 34 is connected to each connector 100 of the control board 60.

After that, the head identification information ID1 to ID24 stored in the storage unit 35 of each inkjet head 34 connected to each connector 100 is read by the reading circuit 201, acquired by the CPU 91 of the mechanical controller 90, and the number of each connector 100. C1 to C24 and the head identification information ID1 to ID24 of each inkjet head 34 connected to each connector 100 are stored in the head connection information storage unit 202 in association with each other.

That is, for example, the number C1 of the connector 100 and the head identification information ID1 of the inkjet head 34 connected to the connector 100 of the number C1 are stored in the table in association with each other, and the number C2 of the connector 100 and the number C2 thereof are stored. The head identification information ID2 of the inkjet head 34 connected to the connector 100 is associated and stored in the table.

Then, the CPU 91 of the mechanical controller 90 includes a determination unit 91a, and the determination unit 91a acquires the identification information of the inkjet head 34 read by the reading circuit 201, and the identification information is head connection information stored in advance. It is determined whether or not

That is, for example, when the inkjet head 34 is replaced due to a failure or the like, the head identification information stored in the storage unit 35 of the replaced new inkjet head 34 is read by the read circuit 201 and acquired by the determination unit 91a. It

The determination unit 91a refers to the table stored in the head connection information storage unit 202, and head identification information corresponding to the number of the connector 100 to which the new inkjet head 34 is connected (head identification information of the inkjet head 34 before replacement). Is obtained, and it is determined that the head identification information of the inkjet head 34 before the replacement and the head identification information of the new inkjet head 34 are different. Then, the CPU 91 of the mechanical controller 90 recognizes that the inkjet head 34 has been replaced, based on this determination result.

Then, the determination unit 91a determines that the identification information of the at least two inkjet heads 34 is different from the head connection information, that is, at least two inkjet heads 34 are replaced, and the data line connected to the replaced new inkjet head 34. If the connector 100 to which 101 is connected is incorrect, the head control circuit 84 outputs the new inkjet head 34 to the connector 100 to which the correct control data is supplied so that the new inkjet head 34 is supplied with the correct control data. Switch control data.

7 and 8 are explanatory diagrams for explaining the print result when the above-mentioned connection error of the data line 101 occurs. In FIG. 7 and FIG. 8, six ink jet heads are indicated by 1 to 6, and the print results when the control data representing the character “A” are input to the ink jet heads 1 to 6 are shown.

FIG. 7 shows a printing result when the data lines 101 of the inkjet heads 1 to 6 are correctly connected to the connector 100 of the control board 60, and FIG. 8 shows the data lines of the inkjet heads 1 to 6. 101 shows the printing result when 101 is mistakenly connected to the connector 100 of the control board 60. Specifically, in FIG. 8, the connector 100 to which the data line of the inkjet head 1 is connected and the connector 100 to which the data line of the inkjet head 2 is connected are replaced, and the connector 100 to which the data line of the inkjet head 3 is connected. 5 shows a printing result when the connector 100 to which the data line of the inkjet head 4 is connected is replaced.

As shown in FIG. 8, the control data input to the inkjet head 1 and the inkjet head 2 are exchanged with each other, and the control data input to the inkjet head 3 and the inkjet head 4 are exchanged with each other. Therefore, the print result is “A”. It is not a letter.

Therefore, the head control circuit 84 of the present embodiment has a circuit configuration in which correct control data is supplied to the inkjet heads 1 to 4. Specifically, as shown in FIG. 5, the head control circuit 84 includes a connector 1 MUX 203 and a connector 2 MUX 204.

The MUX 203 for connector 1 is a multiplexer, and is supplied to the inkjet head 34 correctly connected to the connector 2 and control data to be supplied to the inkjet head 34 correctly connected to the connector 1 (control data for connector 1). The control data (control data for connector 2) to be input is input, and its output terminal is connected to the connector 1.

The MUX 204 for the connector 2 is also a multiplexer and is supplied to the inkjet head 34 correctly connected to the connector 2 and the control data to be supplied to the inkjet head 34 correctly connected to the connector 1 (control data for the connector 1). The control data (control data for connector 2) to be input is input, and its output terminal is connected to the connector 2.

Then, for example, when the data line 101 (inkjet head 34) to be connected to the connector 1 is connected to the connector 2 and the data line 101 (inkjet head 34) to be connected to the connector 2 is connected to the connector 1, The CPU 91 of the mechanical controller 90 switches the MUX 203 for the connector 1 so that the control data for the connector 2 is supplied to the connector 1. Further, the CPU 91 of the mechanical controller 90 switches the MUX 204 for the connector 2 so that the control data for the connector 1 is supplied to the connector 2. As a result, correct control data is supplied to the inkjet head 34 connected to the connector 1 and the connector 2, and a correct print result can be obtained.

An incorrect portion of the connector 100 to which the data line 101 is connected is confirmed by printing a test pattern.

That is, as described above, when the determination unit 91a determines that the identification information of at least two inkjet heads 34 is different from the head connection information, that is, when it is recognized that at least two inkjet heads 34 have been replaced. First, the mechanical controller 90 outputs a control signal to the image control circuit 83 and the head control circuit 84 via the image control I/F 96 to print a preset test pattern.

The test pattern is preset in the image control circuit 83, and a test pattern having a different pattern for each inkjet head 34 is printed. In this embodiment, as shown in FIG. 9, test patterns of different numbers and colors are printed for each inkjet head 34. The test pattern shown in FIG. 9 is an example in which "123456" is printed in different colors by the line heads 32a to 32d. Characters "1", "2", "3", "4", "5", and "6" are printed by the six inkjet heads 34 constituting each of the line heads 32a to 32d.

Hereinafter, the inkjet head 34 for printing "1" is the first inkjet head 34, the inkjet head 34 for printing "2" is the second inkjet head 34, and the inkjet head 34 for printing "3" is the third inkjet head 34. The inkjet head 34 for printing “4” is the fourth inkjet head 34, the inkjet head 34 for printing “5” is the fifth inkjet head 34, and the inkjet head 34 for printing “6” is the second inkjet head 34. 6 inkjet head 34.

Further, the connector 100 to which the data line 101 of the first inkjet head 34 should be connected is the first connector 100, and the connector 100 to which the data line 101 of the second inkjet head 34 should be connected is the second connector 100, The connector 100 to which the data line 101 of the third inkjet head 34 should be connected is the third connector 100, and the connector 100 to which the data line 101 of the fourth inkjet head 34 should be connected is the fourth connector 100 and the fifth connector 100. The connector 100 to which the data line 101 of the inkjet head 34 is connected is referred to as a fifth connector 100, and the connector 100 to which the data line 101 of the sixth inkjet head 34 is connected is referred to as a sixth connector 100.

In the print result of the test pattern shown in FIG. 9, black "3" and "4" are interchanged, and black "5" and "6" are interchanged. From the printing result, the data line 101 of the third inkjet head 34 of the line head 32a is erroneously connected to the fourth connector 100, and the data line 101 of the fourth inkjet head 34 is erroneously connected to the third connector. It can be seen that it is connected to 100. Further, the data line 101 of the fifth inkjet head 34 is erroneously connected to the sixth connector 100, and the data line 101 of the sixth inkjet head 34 is erroneously connected to the fifth connector 100. I understand.

In the present embodiment, since the test pattern as described above is printed, it is possible to immediately grasp which inkjet head 34 has incorrect data line wiring by a simple method.

Therefore, the user inputs control data for printing the character “4” to the third connector 100 based on the print result, and prints the character “3” to the fourth connector 100. Switching information for inputting control data is set and input on the operation panel 70.

Further, the user inputs control data for printing the character “6” to the fifth connector 100 and control data for printing the character “5” to the sixth connector 100. Various switching information is set and input on the operation panel 70.

The switching information set and input on the operation panel 70 is acquired by the user I/F 86 and output to the mechanical controller 90 via the mechanical controller I/F 85 and the main controller I/F 93. The CPU 91 of the mechanical controller 90 switches multiplexers such as the MUX 203 for connector 1 and the MUX 204 for connector 2 shown in FIG. 5, based on the input switching information.

Note that the circuit configuration example shown in FIG. 5 is a circuit configuration example in the case of switching control data input to the connector 1 and the connector 2, but, for example, as described above, six inkjet heads 34 are connected. When switching the control data input to the connector 100, multiplexers such as the MUX 203 for the connector 1 and the MUX 204 for the connector 2 are provided for each connector 100 and input to the six connectors 100 for each multiplexer. The control data to be input is input.

The control data input to the multiplexer may be the control data to be input to all the inkjet heads 34, or the control data to be input to the six inkjet heads 34 included in one line head 32a to 32d. It may be data.

Then, specifically, the CPU 91 controls the above multiplexer to output the control data for printing the character “4” to the third connector 100, and to control the data for printing the character “3”. The switching is performed so that the output destination of is the fourth connector 100.

Further, the CPU 91 controls the multiplexer described above so that the output destination of the control data for printing the character “6” is the fifth connector 100 and the output destination of the control data for printing the character “5” is the first. Switching is performed so that the connector 100 of No. 6 is obtained.

Further, the head control circuit 84 acquires the head characteristic information stored in the storage unit 35 of each inkjet head 34, and based on the head characteristic information, an appropriate reference voltage and drive for each inkjet head 34. A voltage signal having a waveform is supplied. The specific circuit configuration will be described below.

As shown in FIG. 5, the head control circuit 84 is connected to the connector 1 characteristic information register 205 for storing the head characteristic information read from the storage unit 35 of the inkjet head 34 connected to the connector 1 and the connector 2. The connector 2 characteristic information register 206 for storing the head characteristic information read from the storage unit 35 of the inkjet head 34 is provided.

The head characteristic information read from the storage unit 35 of the inkjet head 34 connected to the connector 1 is temporarily stored in the connector 1 characteristic information register 205 and then output to the connector 1 voltage generation circuit 207. The connector 1 voltage generation circuit 207 generates an appropriate voltage signal for the inkjet head 34 connected to the connector 1 based on the input head characteristic information, and outputs the voltage signal to the connector 1.

The head characteristic information read from the storage unit 35 of the inkjet head 34 connected to the connector 2 is temporarily stored in the connector 2 characteristic information register 206 and then output to the connector 2 voltage generation circuit 208. The connector 2 voltage generation circuit 208 generates an appropriate voltage signal for the inkjet head 34 connected to the connector 2 based on the input head characteristic information, and outputs the voltage signal to the connector 2.

Thereby, a more appropriate voltage signal can be supplied to the inkjet heads 34 connected to the connector 1 and the connector 2, respectively, and each inkjet head 34 can be operated more appropriately.

Next, the operation of the inkjet printing apparatus 1 according to the present embodiment will be described with reference to the flowchart shown in FIG. Note that, here, the operation when the inkjet head 34 is replaced will be mainly described.

First, the read circuit 201 reads the head identification information stored in the storage unit 35 of each inkjet head 34, and the determination unit 91a acquires the head identification information (S10).

Then, the determination unit 91a refers to the table (head connection information) stored in the head connection information storage unit 202, and the head identification information acquired from each connector 100 with the numbers C1 to C24 corresponds to each connector 100 in the table. It is determined whether there is a difference of two or more from the head identification information corresponding to the numbers C1 to C24 (S12).

Then, when there are two or more pieces of head identification information different from those in the above table (S12, YES), when it is recognized that at least two inkjet heads 34 have been replaced, the mechanical controller 90 causes the image control I A control signal is output to the image control circuit 83 and the head control circuit 84 via /F96 to print a preset test pattern (S14).

Next, the user confirms the print result of the test pattern, and if a wiring error of the data line 101 has occurred, an operation is performed so that correct control data is input for the connector 100 having the wiring error. Switching information is set and input using the panel 70 (S16).

The switching information set and input on the operation panel 70 is acquired by the CPU 91 of the mechanical controller 90, and the CPU 91 outputs a control signal to the head control circuit 84 based on the input switching information, and the MUX 203 for connector 1 and the connector 2 are output. The MUX 204 for use is switched (S18). That is, the CPU 91 performs switching so that correct control data is input to the connector 100 in which wiring error has occurred.

Then, the CPU 91 of the mechanical controller 90 updates the table of the head connection information storage unit 202 by rewriting the head identification information corresponding to the numbers C1 to C24 of the connector 100 with the head identification information of the newly replaced inkjet head 34. Yes (S20).

Specifically, for example, the inkjet head 34 of the head identification information ID1 connected to the connector 100 of the number C1 is replaced with the inkjet head 34 of the head identification information ID25, and the head identification information ID2 connected to the connector 100 of the number C2. When the inkjet head 34 of No. 2 is replaced with the inkjet head 34 of the head identification information ID 26, the data line 101 of the inkjet head 34 of the head identification information ID 25 is mistakenly connected to the connector 100 of the number C2, and the head identification information When the data line 101 of the inkjet head 34 of ID26 is connected to the connector 100 of number C1, the head identification information ID26 is stored as the head identification information of the inkjet head 34 corresponding to number C1 and corresponds to the number C2. The table is updated by storing the head identification information ID 25 as the head identification information of the inkjet head 34 to be operated.

On the other hand, in S12, when the determination unit 91a determines that the head identification information acquired from each connector 100 with the numbers C1 to C24 is different from the head identification information corresponding to the numbers C1 to C24 in the table by one, (S12, NO, S22, YES), the CPU 91 of the mechanical controller 90 rewrites the head identification information corresponding to the numbers C1 to C24 of the connector 100 with the head identification information of the newly replaced inkjet head 34 to connect the heads. The table of the information storage unit 202 is updated, and the process ends (S20).

As described above, when the head identification information acquired from each connector 100 of the numbers C1 to C24 is different from the table by one, only the table is updated and the test pattern is not printed. Can be prevented from being printed.

Further, when the determination unit 91a determines that the head identification information acquired from each connector 100 of the numbers C1 to C24 and the head identification information corresponding to the numbers C1 to C24 in the table are all the same (S22, NO). The process ends without updating the table of the head connection information storage unit 202.

In the above-described embodiment, the user sets and inputs the switching information of the control data input to each connector 100 on the operation panel 70. However, the present invention is not limited to this, and is printed by the print processing unit 30, for example. The switching information may be automatically generated by photoelectrically reading the test pattern and analyzing the read test pattern data.

Specifically, as shown in FIG. 11, an image sensor 36 is provided on the downstream side of the print processing unit 30, and the image sensor 36 photoelectrically reads the test pattern. Then, the CPU 91 of the mechanical controller 90 acquires the read test pattern data and performs character recognition and color recognition to recognize whether or not there is a wiring error in the data line 101. Then, the CPU 91 generates switching information based on the recognition result, and performs switching of control data similar to the above based on the switching information.

Although the image sensor 36 for photoelectrically reading the test pattern is newly provided in the embodiment shown in FIG. 11, an existing image sensor may be used. Specifically, for example, the test pattern may be read photoelectrically by a paper width detection sensor provided on the upstream side of the print processing unit 30.

The paper width detection sensor is originally a sensor for detecting the width of the print medium P in the direction orthogonal to the conveyance direction, and the width of the image data to be printed is adjusted based on the width. When an image sensor is used as the paper width detection sensor, the test pattern can be read by this. However, since the paper width detection sensor is provided on the upstream side of the print processing unit 30, after the test pattern is printed on the print medium P and then inverted by the reversing unit 50, the test pattern of the paper width detection sensor is changed. Read is done.

In addition, when the switching information is generated based on the test pattern data obtained by photoelectrically reading the test pattern as described above, it is necessary to perform character recognition in the case of a number like the test pattern shown in FIG. Processing becomes complicated.

Therefore, it is preferable to use a test pattern that can be easily analyzed. Specifically, for example, as shown in FIG. 12, switching patterns may be generated by printing rectangular patterns of different lengths for each inkjet head 34 and analyzing the arrangement of the rectangular patterns. Further, as shown in FIG. 13, different numbers of patterns (for example, black rectangular patterns) may be printed for each inkjet head 34, and the switching information may be generated by analyzing the number of these patterns. 12 and 13 are examples in which the test patterns are printed by the six inkjet heads 34 of the line head 32a. Alternatively, the user may confirm the test patterns shown in FIGS. 12 and 13 and set and input the switching information on the operation panel 70.

Further, when the control data input to each connector 100 is switched based on the switching information as in the inkjet printing apparatus 1 of the above embodiment, further maintenance such as replacement of the inkjet head 34 is performed thereafter. When performing, since the control data input to each connector 100 has already been exchanged, the wiring of the data line 101 of the new inkjet head 34 may be further erroneous.

Therefore, for example, the switching states (switching states) of the MUX 203 for the connector 1 and the MUX 204 for the connector 2 may be displayed on the operation panel 70 and presented to the user. Specifically, the CPU 91 of the mechanical controller 90 outputs the switching states of the MUX 203 for connector 1 and the MUX 204 for connector 2 to the main controller 80, and the main controller 80 shows the input switching state on the operation panel 70. Display by etc. Alternatively, the main controller 80 may generate a wiring diagram based on the input switching state and print the wiring diagram on the print medium P by controlling the image control circuit 83 and the head control circuit 84.

As a result, the user can check the current wiring state, so that further wiring mistakes can be prevented.

Regarding the inkjet printing apparatus of the present invention, the following additional notes are disclosed.
(Appendix)

In the inkjet printing apparatus of the present invention, each inkjet head may have a characteristic information storage unit that stores characteristic information unique to each inkjet head, and the head control circuit may read each inkjet head from the characteristic information storage unit. Each inkjet head can be controlled based on the characteristic information of.

In addition, in the inkjet printing apparatus of the present invention, when the determination unit determines that the identification information of at least two inkjet heads is different from the head connection information, the head control circuit is connected to each connector via the data line. Control data representing different patterns of images is output to each inkjet head, and the head control circuit switches the connector to which the control data is output based on the print result of the control data of different patterns. It is preferred that

Further, in the inkjet printing apparatus of the present invention, when the determination unit determines that only the identification information of one inkjet head is different from the head connection information, the identification information of the inkjet head different from the head connection information is used as new identification information. It is preferable that the head connection information is stored and updated.

Further, in the inkjet printing apparatus of the present invention, it is preferable that the switching state of the connector of the control data output destination in the head control circuit is output.

DESCRIPTION OF SYMBOLS 1 Inkjet printer 10 Side paper feed unit 11 Paper feed tray 12 Primary paper feed unit 14 Secondary paper feed unit 20 Internal paper feed units 21a to 21d Paper feed units 22a to 22d Primary paper feed unit 30 Print processing unit 31 Head Units 32a to 32d Line head 33 Head holder 34 Inkjet head 35 Storage unit 36 Image sensor 40 Paper discharging unit 41 Paper discharging table 42 Paper discharging roller 43 Switching mechanism 50 Reversing unit 51 Reversing table 52 Reversing roller 53 Conveying roller 60 Control board 70 Operation Panel 80 Main controller 81 CPU
82 memory 83 image control circuit 84 head control circuit 85 mechanical controller I/F
86 User I/F
87 External I/F
90 Mechanical controller 91 CPU
91a Judgment unit 92 Memory 93 Main controller I/F
94 sensor I/F
95 Actuator I/F
96 Image control I/F
100 Connector 101 Data Lines 131 and 132 Suction Fan 133 Conveyor Belt 201 Reading Circuit 202 Head Connection Information Storage Unit 203 Connector 1 MUX
204 MUX for connector 2
205 Connector 1 Characteristic Information Register 206 Connector 2 Characteristic Information Register 207 Connector 1 Voltage Generating Circuit 208 Connector 2 Voltage Generating Circuit CR Circulating Conveying Route FR Paper Feed Conveying C1 to C24 Connector Numbers ID1 to ID24 Head Identification Information P Printing Medium

Claims (5)

A plurality of inkjet heads for ejecting ink to the print medium,
A control board having a plurality of connectors and a head control circuit that supplies control data for each of the inkjet heads to the connectors;
One end is connected to each inkjet head, the other end is connected to each connector, and a plurality of data lines that respectively supply the control data output from each connector to each inkjet head,
A head connection information storage unit that stores in advance head connection information in which the respective connectors and the identification information of the inkjet heads connected to the respective connectors via the data lines are associated with each other,
A determination unit for determining whether or not the identification information of each inkjet head connected to each connector via the data line is acquired and different from the head connection information;
The head control circuit determines that the identification information of at least two of the inkjet heads is different from the head connection information by the determination unit, and connects the data lines connected to the inkjet heads of the identification information different from the head connection information. An inkjet printing apparatus that switches control data to be output to the connector so that the correct control data is output to an inkjet head having identification information different from the head connection information when the connector is incorrect. Each of the inkjet heads has a characteristic information storage unit that stores characteristic information unique to each inkjet head,
The inkjet printing apparatus according to claim 1, wherein the head control circuit controls the inkjet heads based on characteristic information of the inkjet heads read from the characteristic information storage unit. When the determination unit determines that the identification information of at least two of the inkjet heads is different from the head connection information,
The head control circuit outputs control data representing images of different patterns to the inkjet heads connected to the connectors via the data lines,
3. The inkjet printing apparatus according to claim 1, wherein the head control circuit switches the output destination connector of the control data based on the print result of the control data having a different pattern for each inkjet head. When the determination unit determines that only the identification information of one of the inkjet heads is different from the head connection information, the identification information of the inkjet head different from the head connection information is stored as new identification information and the head connection information is stored. The ink jet printing apparatus according to claim 1, wherein is updated. 5. The inkjet printing apparatus according to claim 1, wherein a switching state of a connector to which the control data is output in the head control circuit is output.