WO2022186334A1

WO2022186334A1 - Inkjet recording device

Info

Publication number: WO2022186334A1
Application number: PCT/JP2022/009128
Authority: WO
Inventors: 正輝西原
Original assignee: 京セラドキュメントソリューションズ株式会社
Priority date: 2021-03-05
Filing date: 2022-03-03
Publication date: 2022-09-09

Abstract

An inkjet recording device (1) is provided with: an endless transport belt (46) on which recording paper is loaded and transported; a line head (23) for each line, the line heads ejecting ink onto the recording paper transported by the transport belt (46), and forming an image on the recording paper; and a control unit (600) which turns on the drive power of the line head (23) for each line when the transport belt (46) is being driven, and turns off the drive power of the line head (23) for each line when the transport belt (46) is stopped.

Description

Inkjet recording device

The present invention relates to an inkjet recording apparatus that forms an image on the recording paper by ejecting ink onto the recording paper while the recording paper is transported by a transport belt, and more particularly to a technique for cooling the inkjet head and the inside of the device.

Generally, an inkjet recording apparatus is known that ejects ink from an inkjet head onto the recording paper to form an image on the recording paper while the recording paper is being transported by a transport belt.

For example, the recording head driving device described in Patent Document 1 is provided with two driving circuits for one inkjet head, and a driving switching circuit switches between the driving circuits based on the pattern information stored in the pattern registration unit. It is operated so that the heat generated in each drive circuit is efficiently dissipated.

JP 2010-228241 A

Here, in the inkjet recording apparatus, when the temperature of the inkjet head rises, the temperature of the ink also rises, and the rise in the ink temperature causes the deterioration of the image quality.

In particular, when using an inkjet head that consumes more power as its functions improve, not only does the amount of heat generated by the inkjet head during operation increase, but the power consumption of the inkjet head decreases even during standby. Therefore, the temperature of the ink rises due to the heat generated by the inkjet head. Moreover, since the temperature inside the apparatus rises due to the heat generated by the inkjet head, the temperature rise of the ink cannot be solved unless the temperature rise inside the apparatus is suppressed.

Although Patent Document 1 discloses a technique for dissipating the heat generated by each drive circuit while the inkjet head is being driven, there is no technical description or suggestion for suppressing the temperature inside the device that rises due to heat dissipation. In order to solve the above problem, for example, it is conceivable to separately provide a cooling fan, but in this case the number of parts and power consumption increase.

The present invention has been made in view of the above circumstances, and an object of the present invention is to suppress the temperature rise of the inkjet head and the temperature inside the device without providing a cooling fan.

An inkjet recording apparatus according to one aspect of the present invention forms an image on an endless conveyor belt on which recording paper is placed and ejects ink onto the recording paper being conveyed by the conveyor belt. An inkjet head and a control unit for turning on the driving power of the inkjet head when the transport belt is driven and turning off the driving power of the inkjet head when the transport belt is stopped.

According to the present invention, the driving power of the inkjet head is turned on while the transport belt is driving. That is, the driving power of the ink jet head is turned on when the conveying belt rotates and air convection is generated around the conveying belt. As a result, the ink jet head is cooled by the air convection, and the air inside the apparatus is ventilated by the air convection. Further, the driving power of the inkjet head is turned off when the conveying belt is not driven. As a result, the temperature of the ink inside the inkjet head and the temperature inside the apparatus do not rise even if air convection does not occur due to the circular movement of the conveying belt. As a result, the temperature rise of the inkjet head and the temperature rise inside the apparatus can be suppressed without providing a cooling fan.

1 is a cross-sectional view of an inkjet recording apparatus; FIG. 1 is a functional block diagram showing the main internal configuration of an inkjet recording apparatus; FIG. 5 is a flow chart showing a control procedure by cooperation between a head control unit and a transport control unit;

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of an inkjet recording apparatus 1 according to one embodiment of the invention. The inkjet recording apparatus 1 includes an operation section 11 , a document reading section 12 , an image recording section 13 , a paper feeding section 14 , a conveying section 15 , a conveying unit 16 and a cap section 18 .

The operation unit 11 is operated by the user to input instructions regarding various operations and processes executed by the inkjet recording apparatus 1 . For example, the operation unit 11 includes physical keys such as a numeric keypad, an enter key, or a start key, and a touch panel provided on the screen of the display unit.

When a plurality of manuscripts MS are placed on the manuscript tray 22, the manuscript reading unit 12 sequentially pulls out the manuscripts MS from the manuscript tray 22 and conveys them, while reading the image of one side of each manuscript MS with an imaging device. Alternatively, images on both sides of each document MS are simultaneously read by two imaging devices, and each document MS is discharged sequentially. The document reading unit 12 converts the analog output of each image sensor into a digital signal to generate image data representing the image of the document MS.

The image recording unit 13 prints the image of the document MS indicated by the image data on recording paper. The image recording unit 13 ejects ink droplets of four colors (black, cyan, magenta, and yellow) onto the recording paper P conveyed from the paper feeding unit 14 to record a color image. Specifically, the image recording unit 13 has line heads (an example of inkjet heads) 23 corresponding to the respective colors of black, cyan, magenta, and yellow. That is, the inkjet recording apparatus 1 is a line head type inkjet recording apparatus. Note that the line head 23 is provided with a voltage control section 23A that controls the drive voltage applied to the line head 23 .

The paper feed unit 14 includes a paper feed cassette 27 . A paper feed roller 28 is provided in the paper feed cassette 27 . The paper feed unit 14 causes the paper feed roller 28 to pull out the recording paper P contained in the paper feed cassette 27 and transport it to the transport path 31 .

The paper feeding unit 14 also includes a manual feed tray 32 provided on the wall surface of the apparatus main body. The paper feed unit 14 causes the paper feed roller 33 to pull out the recording paper P set in the manual feed tray 32 and transport it to the transport path 31 .

The transport unit 15 includes a transport path 31 for transporting the recording paper P transported from the paper feeding unit 14, a transport path 38 for transporting the recording paper P transported through the transport unit 16, and transport paths 31 and 38. Provided transport rollers 35, registration rollers 36 for feeding the recording paper P to the transport unit 16 while correcting oblique feeding of the recording paper P, and discharge for discharging the recording paper P transported through the transport path 38 to the discharge tray 41. A roller 42 and the like are provided.

The transport unit 16 includes a drive roller 43 , a driven roller 44 , a tension roller 45 and a transport belt 46 . The conveying belt 46 is an endless belt and stretched over the driving roller 43 , the driven roller 44 and the tension roller 45 . The drive roller 43 is rotationally driven counterclockwise by a motor. As the drive roller 43 is rotationally driven, the conveying belt 46 rotates counterclockwise, and the driven roller 44 and the tension roller 45 are driven to rotate counterclockwise.

The tension roller 45 keeps the tension of the conveyor belt 46 in an appropriate state. The attracting roller 47 is in contact with the conveying belt 46 , and electrifies the conveying belt 46 to electrostatically attract the recording paper P fed from the paper feeding unit 14 to the conveying belt 46 .

The elevating mechanism 48 supports the transport unit 16 from below and vertically moves the transport unit 16 with respect to each line head 23 of the image recording section 13 . That is, the lifting mechanism 48 separates and approaches the transport unit 16 and each line head 23 by moving the transport unit 16 relative to each line head 23 . Specifically, the lifting mechanism 48 moves the transport unit 16 between a recording position (the position shown in FIG. 1) where printing by the image recording unit 13 is possible and a maintenance position a predetermined distance below the recording position. to move. The lifting mechanism 48 is an example of a moving mechanism in the claims.

When the transport unit 16 is lowered to the maintenance position by the lifting mechanism 48, an empty space is formed below the image recording section 13. In this state, the moving mechanism 56 (shown in FIG. 2) horizontally moves the cap portion 18 to the lower side of the image recording portion 13, and then moves the cap portion 18 upward. As a result, the nozzles of the line heads 23 of the image recording section 13 are overlapped and covered with the cap section 18, and the ink of the nozzles of the line heads 23 of the image recording section 13 is prevented from drying.

A branch path 51 is connected to the transport path 38 , and a branch claw 52 is provided at a connection point between the transport path 38 and the branch path 51 . A reversing transport path 54 is connected to the branch path 51 , and a branch claw 55 is provided at a connection point between the branch path 51 and the reversing transport path 54 . The branch claw 52 guides the recording paper P to the discharge roller 42 through the transport path 38 or to the branch path 51 . When the recording paper P is guided from the transport path 38 to the branch path 51 by the branch claw 52, the recording paper P is transported to the transport roller 53 through the branch path 51, and the transport roller 53 stops temporarily and rotates in the reverse direction. , the trailing edge of the recording paper P is guided from the transport roller 53 to the reversing transport path 54 by the branch claw 55 , and the recording paper P is returned to the image recording section 13 through the reversing transport path 54 . As a result, the recording paper P is turned upside down.

When the image of the document MS is recorded only on the surface of the recording paper P by the image recording unit 13, the recording paper P is discharged through the transport path 38 after the image is recorded on the surface of the recording paper P by the image recording unit 13. It is guided to the rollers 42 and discharged to the discharge tray 41 .

When the image recording unit 13 records images of two sheets of the document MS or images of both sides of the document MS on the front and back sides of the recording paper P, one image is recorded on the surface of the recording paper P by the image recording unit 13. After that, the recording paper P is guided from the transport path 38 to the branch path 51, and is returned to the image recording unit 13 through the reversing transport path 54 by the switchback transport, and the recording paper P is turned upside down. The other image is recorded on the back surface of the recording paper P by the image recording unit 13 , and the recording paper P is guided to the discharge roller 42 through the transport path 38 and discharged to the discharge tray 41 .

FIG. 2 is a functional block diagram showing the main internal configuration of the inkjet recording apparatus 1 according to this embodiment. The inkjet recording apparatus 1 moves the operation unit 11, the document reading unit 12, the image recording unit 13, the paper feeding unit 14, the transport unit 15, the transport unit 16, the elevating mechanism 48, and the cap unit 18 horizontally and vertically. It comprises mechanism 56 , image memory 57 and control unit 600 . The same reference numerals are given to the same components as those of the inkjet recording apparatus 1 shown in FIG.

The control unit 600 includes a processor, RAM (Random Access Memory), ROM (Read Only Memory), dedicated hardware circuits, and the like. The processor is, for example, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or an MPU (Micro Processing Unit).

The control unit 600 functions as the control section 60 by the processor executing various programs stored in a non-volatile memory such as a ROM. The control unit 60 functions as a reading control unit 61 , a head control unit 62 , a transport control unit 63 , a mechanism control unit 64 and an overall control unit 65 . The control unit 60, that is, the reading control unit 61, the head control unit 62, the transport control unit 63, the mechanism control unit 64, and the overall control unit 65 are not limited to being realized by executing programs, and are implemented by hardware. It can also be configured by a circuit.

The general control unit 65 is connected to the operation unit 11, the document reading unit 12, the image recording unit 13, the paper feeding unit 14, the transport unit 15, the transport unit 16, the elevating mechanism 48, the moving mechanism 56, and the image memory 57. It governs overall operation control of the recording apparatus 1 .

The reading control unit 61 controls, for example, a motor for driving a conveying roller and an imaging device in the document reading unit 12, causes the document reading unit 12 to convey the document MS, reads an image of the document MS, The image memory 57 stores the image data representing the image of the document MS.

The head control unit 62 controls each line head 23 of the image recording unit 13 based on the image data representing the image of the document MS in the image memory 57, and causes each line head 23 to eject ink, thereby printing the document MS. is recorded on the recording paper P on the transport belt 46 of the transport unit 16 .

The transport control unit 63 includes motors for rotating the paper feed rollers, transport rollers, and registration rollers in the paper feed unit 14, the transport unit 15, and the reversing transport path 54, and actuators for switching the branch claws 52 and 55. , and controls the motor and the like for rotating the drive roller 43 in the transport unit 16 to feed the recording paper P from the paper feed unit 14 and transport the recording paper P. FIG.

The mechanism control section 64 controls the motors, actuators, etc. of the lifting mechanism 48 and the moving mechanism 56 to raise and lower the transport unit 16 and move the cap section 18 horizontally and vertically.

Here, in the general inkjet recording apparatus 1, when the temperature of each line head 23 rises, the temperature of the ink inside each line head 23 also rises, and the temperature rise of the ink causes deterioration of image quality. . The temperature of each line head 23 rises when it is driven, but since each line head 23 is covered with a cap for preventing the ink from drying, heat tends to accumulate inside the head. Further, during the standby period in which each line head 23 is driven and printing is not performed, there is no air convection inside the apparatus, so heat is less likely to move from the inside of the apparatus. Therefore, when the function of each line head 23 is improved and the power consumption increases, even if the increase is slight, heat accumulates inside the device, causing the temperature to rise. Unless the temperature rise inside the device is suppressed, the ink temperature rise cannot be solved.

There is also a measure to install a separate cooling fan to suppress the temperature rise inside the device, but if a cooling fan is installed separately, the number of parts and power consumption will increase.

On the other hand, in the inkjet recording apparatus 1 of the present embodiment, the control section 60 turns on the drive power of each line head 23 while driving the transport belt 46 of the transport unit 16 . When the driving power of each line head 23 is turned on, although each line head 23 generates heat, since the conveyor belt 46 is driven and moves around, air convection occurs around the conveyor belt 46, Each line head 23 arranged along is cooled by the convection of the air. Therefore, the temperature rise of the ink inside each line head 23 is suppressed. Furthermore, since the air inside the device is ventilated through the opening of the device housing by the convection of the air, the temperature rise inside the device can be suppressed.

The control unit 60 also turns off the driving power of each line head 23 when the conveyor belt 46 is stopped. When the driving power for each line head 23 is turned off, each line head 23 does not generate heat and the temperature inside the apparatus does not rise. Therefore, even if the conveying belt 46 stops and air convection ceases to occur, the temperature of the ink inside each line head 23 and the temperature inside the apparatus do not rise.

FIG. 3 is a flow chart showing a control procedure by cooperation between the head control unit 62 and the transport control unit 63. FIG.

General control unit 65 causes document reading unit 12 to read document MS in response to an instruction input to operation unit 11 by the user, stores an image of document MS in image memory 57, and stores an image of document MS. print instruction to the head control unit 62 and the transport control unit 63 . The head control unit 62 receives the print instruction notified from the overall control unit 65 (step S101), and switches the driving power of each line head 23 from off to on to put each line head 23 in an operating state, thereby printing an image. Preparation for data input and setting according to the print instruction are performed (step S102).

Conveyance control unit 63 receives the print instruction notified from general control unit 65 (step S201), and rotates driving roller 43 by switching the driving power of the motor or the like for rotating driving roller 43 from off to on. to rotate the conveyor belt 46 (step S202). That is, the control unit 60 performs control to turn on the driving power of each line head 23 when the transport belt 46 starts to be driven.

At this time, although each line head 23 generates heat, the circular movement of the conveying belt 46 causes air convection around the conveying belt 46, so that each line head 23 is cooled by the air convection. As a result, the temperature rise of the ink inside each line head 23 is suppressed. In addition, since the air inside the apparatus is ventilated through the opening of the apparatus housing by the convection of the air, the temperature rise inside the apparatus can be suppressed.

Subsequently, the head control unit 62 completes preparations for inputting image data and setting according to printing instructions, and sets a predetermined state in which all the line heads 23 can eject ink (for example, the ink temperature is set to the ejection temperature (step S103), a request to start paper feeding is output to the transport control unit 63 (step S104). .

When the transport control unit 63 receives the request to start paper feeding output from the head control unit 62 (step S203), the transport control unit 63 rotates the paper feed rollers, the transport rollers, and the registration rollers in the paper feed unit 14 and the transport unit 15. By controlling the motor and the like, the recording paper P is fed from the paper feeding unit 14 and transported through the transport path 31 (step S204). That is, after the driving power of each line head 23 is turned on, the control unit 60 causes the recording paper P to be fed by the paper feed unit 14 when each line head 23 is in a predetermined state in which ink can be discharged. Control to start paper. The transport control unit 63 further instructs the head control unit 62 on the feeding timing of the recording paper P (step S205). For example, the transport control unit 63 causes a sensor to detect the leading edge of the recording paper P being transported through the transport path 31, and determines and notifies the paper feed timing of the recording paper P based on the detection output of the sensor. The recording paper P is conveyed from the conveying path 31 of the conveying section 15 to the conveying belt 46 of the conveying unit 16 .

When the head control unit 62 accepts the paper feed timing of the recording paper P (step S105), the head control unit 62 ejects the paper according to the image data representing the image of the document MS in the image memory 57 at the ejection timing determined based on the accepted paper feed timing. By controlling each line head 23 with the control of each line head 23, ink is ejected from each line head 23 to record an image of the document MS on the recording paper P on the transport belt 46 (step S106).

When the formation of the image of the document MS by the control of the head control unit 62 is completed, the overall control unit 65 causes the document reading unit 12 to read the next document MS, and generates an image showing the image of the next document MS. The data are stored in the image memory 57 . The overall control unit 65 determines whether or not the image data representing the image of the next document MS is stored in the image memory 57, that is, whether or not there is the next document MS. When determining that there is the next document MS, the general control section 65 notifies the head control section 62 and the transport control section 63 of the print instruction of the image of the document MS again. When the print instruction is received again ("print instruction" in step S107), the head control unit 62 executes the processes from step S103 to step S106. Similarly, when transport control unit 63 receives a print instruction again ("print instruction" in step S206), it executes the processes from step S203 to step S205.

On the other hand, when the overall control unit 65 determines that there is no next document MS, it notifies the transport control unit 63 of the end of printing. When the transport control unit 63 receives the print end notification from the overall control unit 65 ("print end" in step S206), the transport control unit 63 switches the drive power of the motor or the like for rotating the drive roller 43 from on to off. , the conveyor belt 46 is stopped (step S207). After the process of step S207, the transport control unit 63 notifies the head control unit 62 of the end of printing (step S208).

On the other hand, when the head control unit 62 receives the end of printing from the transport control unit 63 ("print end" in step 107), the head control unit 62 switches the driving power of each line head 23 from on to off, thereby turning each line head 23 on. The drive is stopped (step S108). That is, the control unit 60 performs control to turn off the driving power of each line head 23 when the conveying belt 46 is stopped.

At this time, since each line head 23 does not generate heat, the temperature of the ink inside each line head 23 does not rise even if air convection does not occur due to the circular movement of the conveying belt 46 .

As described above, in the above-described embodiment, the drive power for each line head 23 is turned on while the transport belt 46 of the transport unit 16 is being driven. The line head 23 is cooled, and the temperature rise of the ink inside each line head 23 is suppressed. Moreover, the air inside the device is ventilated by the convection of the air, and the temperature rise inside the device is suppressed. Further, in the above embodiment, the driving power of each line head 23 is turned off when the conveyor belt 46 is stopped. The temperature of the ink inside and the temperature inside the device do not rise. Therefore, it is possible to suppress the temperature rise of the ink inside each line head 23 and the temperature rise inside the device without separately providing a cooling fan.

In the above-described embodiment, the transport control unit 63 rotates the driving roller 43 of the transport belt 46 to move the transport belt 46 in a circular motion upon receiving an instruction to print the image of the document MS. It is not limited to such an embodiment. For example, in addition to the above-described operation by the transport control unit 63, the mechanism control unit 64 may also raise and lower the transport unit 16 by receiving a print instruction and operating the elevating mechanism 48 in response to the print instruction. good. The mechanism control section 64 may also perform control such as moving the cap section 18 in the horizontal direction and the vertical direction instead of or in conjunction with the lifting operation. Due to the up-and-down motion of the transport unit 16, a large air convection is generated around the transport belt 46, so that each line head 23 is further cooled, and the temperature rise of the ink inside each line head 23 is suppressed more effectively. be done. Moreover, the air inside the device is further ventilated by the large air convection, and the temperature rise inside the device is suppressed more effectively.

In the above embodiment, the head control unit 62 switches the driving power of each line head 23 from off to on when an instruction to print the image of the document MS is received. Not limited. For example, the head control unit 62 may be set in advance so that the recording paper P reaches each line head 23 and all the line heads 23 are ready to eject ink, not when the print instruction is received, but after the print instruction is received. By switching the driving power of each line head 23 from OFF to ON at a predetermined timing before the paper feeding timing instructed by the conveyance control unit 63, each line head 23 is brought into an operating state. can be As a result, the timing at which each line head 23 starts to generate heat can be delayed, and the amount of heat generated by each line head 23 can be reduced.

The configuration and processing of the above embodiment described using FIGS. 1 to 3 are merely one embodiment of the present invention, and are not meant to limit the present invention to the configuration and processing.

Claims

an endless conveyor belt on which recording paper is placed and conveyed;
an inkjet head that forms an image on the recording paper by ejecting ink onto the recording paper being transported by the transport belt;
an inkjet recording apparatus comprising: a control unit that turns on drive power for the inkjet head when the transport belt is driven, and turns off drive power for the inkjet head when the transport belt is stopped. .
2. The inkjet recording apparatus according to claim 1, wherein the control unit turns on the driving power of the inkjet head when the transport belt starts to be driven, and turns off the driving power of the inkjet head when the transport belt ends.
A paper feed unit for supplying the recording paper to the transport belt,
The control unit causes the paper feed unit to start feeding the recording paper when the ink jet head reaches a predetermined state in which ink can be ejected after the driving power of the ink jet head is turned on. 2. The ink jet recording apparatus according to claim 1.
2. The inkjet recording apparatus according to claim 1, wherein the inkjet head is provided with a voltage control section for controlling a driving voltage applied to the inkjet head.
further comprising a movement mechanism for generating air convection inside the inkjet recording apparatus;
2. The inkjet recording apparatus according to claim 1, wherein said control section drives said moving mechanism while said transport belt is being driven.
6. The inkjet recording apparatus according to claim 5, wherein the moving mechanism moves the conveyor belt up and down.
further comprising a cap part covering the nozzles of the inkjet head,
6. The inkjet recording apparatus according to claim 5, wherein said moving mechanism moves said cap portion horizontally and vertically.