Image recording apparatus and cooling method for image recording apparatus

Abstract

To reduce the temperature of a head as early as possible in order to shorten the head replacement time.SOLUTION: An image recording apparatus according to the present invention includes: a plurality of carriages 70, each provided with a recording head 71 that discharges ink for printing; and a control unit 40 having a carriage retreat control part that controls movement of the carriages between a printing position and a carriage retreat position where replacement of the recording head is performed. During replacement of the recording head, the control unit causes the carriage retreat control part to move the carriage to the carriage retreat position so that a distance between the carriage provided with the recording head to be replaced and the other carriages increases.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an image recording apparatus such as an inkjet printing apparatus and a method for cooling the image recording apparatus.

Background Art

[0002] In an image recording apparatus such as an inkjet printing apparatus, the print head may need to be replaced due to the life of the head or a failure. When the image recording apparatus has not been powered on (or is not performing a printing operation) for some time, the head is in a sufficiently cooled state, so the operation of replacing the head can be carried out. However, when a problem gradually occurs during printing and the image quality cannot be guaranteed, the head immediately after the printing operation is very hot (about 80 degrees), and the operation of replacing the head cannot be carried out. Therefore, the operation of replacing the head is performed after the temperature of the head has sufficiently decreased. For example, a waiting time of about 2 hours may occur until the temperature of the head drops.

[0003] A contractor (owner of the printing apparatus) who undertakes printing needs to deliver the requested printing job on schedule. However, since the printing operation cannot be performed until the head replacement is completed, it is desired to shorten the waiting time until the temperature of the head drops.

[0004] As a cooling technique for the head of an image recording apparatus, for example, there is Patent Document 1. Specifically, Patent Document 1 includes a retracting mechanism that retracts the image forming path from the image forming unit when there is an abnormality in the paper conveyance in the image forming path, and a blowing means that blows air from the holding means toward the image forming path in a state where the image forming path is retracted by the retracting mechanism. By changing the exhaust path of the ventilation of the image forming unit, when an obstacle occurs in the conveyance path, the paper staying in the conveyance path can be quickly collected and removed, and damage to the recording head, sensor, etc. of the image forming unit can be avoided. A printing apparatus is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the above prior art, there is a description regarding the cooling of the image forming unit when an obstacle occurs in the conveyance path, but there is no description considering shortening the time until the temperature of the head drops. An object of the present invention is to shorten the head replacement time by lowering the temperature of the head as quickly as possible.

Means for Solving the Problems

[0007] The above problems of the present invention are solved by the following configuration. (1) A control unit having a plurality of carriages provided with a recording head for discharging and printing ink, and a carriage retraction control unit for controlling the movement of the carriage between a printing position and a carriage retraction position for replacing the recording head, wherein when replacing the recording head, the control unit moves the carriage to the carriage retraction position by the carriage retraction control unit so that the distance between the carriage provided with the recording head to be replaced and other carriages becomes wider. An image recording apparatus characterized by the above.

[0008] (2) A head temperature detection unit for obtaining the temperature of the recording head is provided, and the control unit moves the carriage to the carriage retraction position alternately in groups of the carriage by the carriage retraction control unit until the head temperature detection unit detects that the temperature of all the recording heads to be replaced has dropped to a temperature at which the replacement of the recording head is possible. The image recording apparatus according to (1), characterized by the above.

[0009] (3) When the control unit detects that the temperature of all the recording heads to be replaced has dropped to a temperature at which the recording heads can be replaced by the head temperature detection unit, for each carriage provided with a head to be replaced, the carriage provided with the recording head to be replaced is sequentially moved to the carriage retraction position by the carriage retraction control unit. The image recording apparatus according to (2).

[0010] (4) When replacing the recording head, the image recording apparatus according to (1), further comprising a cooling fan that ventilates cooling air between the carriage provided with the recording head to be replaced and another carriage.

[0011] (5) The image recording apparatus according to (1), further comprising an ink heater for heating the ink, and the control unit turns off the ink heater when replacing the recording head.

[0012] (6) The image recording apparatus according to (1), further comprising a head heater for heating the recording head, and the control unit turns off the head heater when replacing the recording head.

[0013] (7) The image recording apparatus according to (1), further comprising an operation panel that displays a message and designates the recording head to be replaced, and the control unit controls the movement of the carriage with the carriage provided with the recording head to be replaced as the user setting by the operation panel, and notifies the operation panel that the replacement work is possible.

[0014] (8) The image recording apparatus according to (1), wherein the carriage retraction position is a direction intersecting the conveyance direction of the recording medium.

[0015] A cooling method for an image recording apparatus having a plurality of carriages provided with a recording head that discharges and prints ink, wherein when replacing the recording head, a carriage retraction control unit moves the carriage from the printing position to a carriage retraction position where the recording head is replaced so that the distance between the carriage provided with the recording head to be replaced and other carriages becomes wider. A cooling method for an image recording apparatus, characterized by including the step of moving the carriage.

Effect of the Invention

[0016] According to the image recording apparatus of the present invention, the position of the carriage is moved so as to lower the temperature of the head as quickly as possible during the standby time when replacing the head, so that the head replacement time can be shortened.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 7A

Figure 7B

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0018] Hereinafter, the image recording apparatus according to the embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a schematic configuration of the image recording apparatus 1.

[0019] The image recording apparatus 1 includes a recording medium supply unit 10, an image forming unit 20, a discharge unit 30, and a control unit 40 (see FIG. 9). Under the control of the control unit 40, the image recording apparatus 1 conveys the recording medium P stored in the recording medium supply unit 10 to the image forming unit 20, forms an image on one or both sides of the recording medium P by the image forming unit 20, and discharges the recording medium P on which the image is formed to the discharge unit 30.

[0020] The paper feed tray 11 is a plate-like member provided so as to be able to place a plurality of recording media P in a stacked state. The paper feed tray 11 is provided so as to move up and down according to the amount of the recording medium P placed on the paper feed tray 11, and is held at the position where the uppermost recording medium P is conveyed by the conveying unit 12 in the vertical movement direction.

[0021] The conveying unit 12 has a conveying mechanism that drives a ring-shaped belt 123 whose inner side is supported by a plurality (for example, two) of rollers 121 and 122 to convey the recording medium P on the belt 123. Further, the conveying unit 12 has a supply unit (not shown in FIG. 1) that delivers the uppermost recording medium P placed on the paper feed tray 11 onto the belt 123. The conveying unit 12 conveys the recording medium P delivered onto the belt 123 along the belt 123.

[0022] The image forming unit 20 includes an image forming drum 50 that supports a recording medium P along a cylindrical outer peripheral surface, and a delivery unit 22 that delivers the recording medium conveyed by the conveyance unit 12 of the recording medium supply unit 10 to the image forming drum 50. Further, the image forming unit 20 includes a first heater 91 that heats the recording medium P supported by the image forming drum 50, and a carriage 70 that ejects ink onto the recording medium P supported by the image forming drum 50 to form an image. Further, the image forming unit 20 includes a cleaning unit 60 (see FIG. 2) that receives the ink ejected from the carriage 70 during maintenance of the carriage 70, and an irradiation unit 93 that irradiates energy rays for curing the ink ejected onto the recording medium P. Further, the image forming unit 20 includes a conveyance mechanism 80 that receives the recording medium P irradiated by the irradiation unit 93 from the image forming drum 50 and selectively performs conveyance to the discharge unit 30 and conveyance that reverses the front and back and returns it to the image forming drum 50 again. Further, the image forming unit 20 includes a second heater 94 etc. that directly heats the outer peripheral surface of the image forming drum 50 without passing through the recording medium P.

[0023] The conveyance mechanism 80 includes a first conveyance drum 81 that receives the recording medium P from the image forming drum 50, a second conveyance drum 82 that receives the recording medium P from the first conveyance drum 81, and a paper discharge drum 83 that receives the recording medium P from the second conveyance drum 82. Further, the conveyance mechanism 80 includes a paper discharge belt mechanism 84 that receives the recording medium P from the paper discharge drum 83 and delivers it to the discharge unit 30, and a front-back inversion drum 85 that receives the recording medium P from the second conveyance drum 82. Further, the conveyance mechanism 80 includes an inversion arm member 86 that separates the recording medium P from the front-back inversion drum 85 and delivers it to the claw portion 51 of the image forming drum 50.

[0024] The first conveyance drum 81, the second conveyance drum 82, the paper discharge drum 83, and the paper discharge belt mechanism 84 of the conveyance mechanism 80 are each rotated in conjunction with the image forming drum 50 by a connection mechanism (not shown). And the inversion arm member 86 reciprocates in conjunction with the image forming drum 50. Further, only the front-back inversion drum 85 has a different conveyance direction length depending on the size of the recording medium P, and thus is rotated by an inversion motor (not shown). That is, the inversion arm member 86 is caused to reciprocate at a timing linked to the rotation of the image forming drum 50. Then, when the inversion arm member 86 reaches the position where it receives the recording medium P from the front-back inversion drum 85, the end of the recording medium P that is not held by the claw portion 851 reaches a position close to and facing the inversion arm member 86. For this reason, rotation speed control according to the size of the recording medium P is required, and the rotation speed of the inversion motor is controlled independently of the rotation of the image forming drum 50.

[0025] The discharge unit 30 has a plate-shaped paper discharge tray 31 or the like on which the recording medium P sent out from the image forming unit 20 by the conveyance mechanism 80 is placed, and stores the recording medium P after image formation until it is taken out by the user.

[0026] FIG. 2 is a perspective view showing the positional relationship between the image forming drum 50 and the cleaning unit 60 and the positions before and after the movement of the carriage 70. The four carriages 70 are individually supported so as to be movable along the X direction, which is the rotation axis direction of the image forming drum 50, within the image forming unit 20. Specifically, as shown in FIG. 2, the carriage 70 is provided so as to be movable between the image forming drum 50 and the cleaning unit 60 arranged along the X direction.

[0027] The carriage 70 moves to a position where the lower surface of the carriage 70 faces the image forming drum 50 during image formation under the control of the control unit 40. Then, during various maintenance operations including head replacement, which will be described later, the lower surface of the carriage 70 moves to a position where it faces the cleaning unit 60. In the following description, the position where the lower surface of the carriage 70 faces the cleaning unit 60 is referred to as the carriage retracted position.

[0028] The cleaning unit 60 has a waste ink unit (not shown) that receives and collects the ink discharged from the carriage 70 during maintenance, and prevents the inside of the image forming unit 20 from being soiled by the ink discharged from the carriage 70 during maintenance.

[0029] Next, the configuration of the carriage 70 will be described. FIG. 3 is a schematic diagram of the internal configuration when the carriage 70 is viewed from below. Here, the upper side means the upper side when one side of the carriage 70 facing the outer peripheral surface of the image forming drum 50 is defined as the lower side of the carriage 70. Further, the view from the side shows the carriage 70 when the carriage 70 is viewed with one side surface of the carriage 70 along the vertical direction and the X direction of the carriage 70 as the front.

[0030] Four carriages 70 are arranged along the conveyance direction F of the recording medium P by the image forming drum 50, and each carriage 70 is arranged in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the upstream side in the conveyance direction. Since the structure of the carriage 70 for each color is the same, only one carriage 70 will be described. The carriage 70 is arranged such that its lower surface is at a predetermined distance from the image forming drum 50 and along the outer peripheral surface of the image forming drum 50.

[0031] The carriage 70 also has a plurality of recording heads 71 and an ink tank (not shown) for storing the ink supplied to each recording head 71. Further, the carriage 70 has an ink heater 73 (see FIG. 9) and a head heater that adjust the temperature of the ink before ejection by heating in an ink path (not shown) leading from the ink tank to each recording head 71. Thereby, the recording head 71 during printing is heated through the heated ink and maintained at a predetermined temperature (for example, about 80 degrees).

[0032] Further, the recording head 71 is detected for temperature by a temperature sensor (not shown), so that it is possible to determine whether or not to replace the high-temperature recording head 71. This temperature sensor may be provided on the recording head 71, or may be provided on the carriage 70 so as to be able to detect the temperature of the recording head 71. A head temperature detection unit described later uses the temperature detected by the temperature sensor as the temperature of the recording head 71.

[0033] The recording head 71 has a plurality of nozzles 711 arranged along a direction parallel to the rotation axis direction (X direction) of the image forming drum 50 and perpendicular to the conveyance direction F of the recording medium P. The recording head 71 individually discharges ink from the plurality of nozzles 711 to form an image on the recording medium P carried by the image forming drum 50. That is, the recording head 71 is provided such that the plurality of nozzles 711 are exposed on the lower surface side of the carriage 70. The recording head 71 has a plurality of nozzles 711 arranged in an arrangement in which two rows of nozzles along the X direction are provided.

[0034] The plurality of recording heads 71 are arranged such that two recording heads 71 form a set, and each set of recording heads 71 forms a row of recording heads 71 provided along the X direction. Further, a plurality of rows of recording heads 71 are provided, and the positional relationship between the sets of recording heads 71 in adjacent rows is arranged in a staggered manner with respect to the direction perpendicular to the X direction (the conveyance direction F in FIG. 1).

[0035] The width of the carriage 70 in the X direction is set to a width (for example, a width smaller than but close to the width of the image forming drum 50) that can sufficiently cover the width of the recording medium P carried and conveyed by the image forming drum 50. Thereby, the carriage 70 performs image formation in a state where the position is fixed with respect to the image forming drum 50. That is, the image recording apparatus 1 is an inkjet recording apparatus of a one-pass system. The carriage 70 is provided with the number of all the nozzles 711 of the plurality of recording heads 71 arranged side by side along the X direction according to the width of the image formed on the recording medium P in the direction perpendicular to the conveyance direction (X direction).

[0036] In the image recording apparatus 1 according to the embodiment, when replacing the head due to a decrease in image quality during the printing operation or the like, the carriage 70 is moved so that the temperature of the head drops as quickly as possible, thereby shortening the waiting time until the head replacement. Hereinafter, the movement of the carriage 70 during the head replacement will be described in detail.

[0037] FIG. 4 is a schematic view of the carriage 70 during the printing operation as viewed from above. Four carriages 70 are arranged along the conveyance direction F of the recording medium P by the image forming drum 50, and each carriage 70 having the same shape is arranged in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the upstream side in the conveyance direction.

[0038] FIG. 5 is a diagram showing the position of the carriage 70 when replacing the head of the magenta (M) carriage 70 as an example. When replacing the head of the carriage 70, only the carriage 70 provided with the head to be replaced is moved to the carriage retracted position so that the distance between the carriage provided with the head to be replaced and the other carriages becomes wider. Then, after the temperature of the recording head 71 (carriage 70) drops to a predetermined temperature, the head replacement is performed. Thereby, since it can be cooled in a state where the density of the head is reduced, the heat dissipation time can be shortened. Further, since a space is generated before and after the carriage 70 in the conveyance direction F, as shown in FIG. 3, the replacement of the set of recording heads 71 arranged in two rows in the X direction can be easily performed.

[0039] Also, when the image recording apparatus 1 of the embodiment performs head replacement during the printing operation, the image recording apparatus 1 divides each carriage 70 into two sets so that the distance between the carriage provided with the head to be replaced and the other carriage becomes wider. Then, the image recording apparatus 1 moves in the arrangement patterns shown in FIGS. 6A and 6B at regular intervals (for example, every 5 minutes), and alternately moves the sets of carriages 70 to the carriage retracted position. Then, after the temperature of the recording head 71 has dropped to a predetermined temperature, only the carriage 70 provided with the head to be replaced may be moved to the carriage retracted position to perform head replacement. Thereby, since it can cool in the state where the density of the carriage 70 has decreased, the heat dissipation time can be shortened. Further, since a space is created before and after the carriage 70 in the transport direction F, as shown in FIG. 3, it is possible to easily replace the sets of recording heads 71 arranged in two rows in the X direction.

[0040] Furthermore, when the image recording apparatus 1 of the embodiment performs head replacement during the printing operation, the image recording apparatus 1 divides each carriage 70 into two sets. Then, the image recording apparatus 1 alternately moves in the arrangement patterns shown in FIGS. 7A and 7B at regular intervals (for example, every 5 minutes), and alternately moves the sets of carriages 70 to the carriage retracted position. Then, after the temperature of the recording head 71 has dropped to a predetermined temperature, head replacement may be performed. The sets of carriages 70 are not limited to two, and may be divided into two or more sets.

[0041] Thereby, the image recording apparatus 1 can cool in the state where the density of the carriage 70 has decreased, so the heat dissipation time can be shortened. Further, since a space is created before and after the carriage 70 in the transport direction F, as shown in FIG. 3, it is possible to easily replace the sets of recording heads 71 arranged in two rows in the X direction.

[0042] In the former method of moving only the carriage 70 for head replacement to the carriage retracted position, when the image recording apparatus 1 performs head replacement of a plurality of carriages 70, for each carriage 70 for head replacement, it moves to the carriage retracted position for cooling and performs head replacement.

[0043] On the other hand, in the latter case, as shown in FIGS. 6A and 6B, or FIGS. 7A and 7B, the image recording apparatus 1 periodically moves all the carriages 70 to the carriage retracted position to widen the interval between the carriages and coarsen the density of the carriages 70, and cools all the carriages 70. Thereby, the recording head 71 of the carriage 70 is cooled. Then, after cooling all the recording heads 71 to be replaced, the image recording apparatus 1 moves the carriages 70 provided with the recording heads 71 to be replaced one by one to the carriage retracted position to replace the recording heads 71. As a result, the waiting time for temperature drop is reduced, and the head replacement can be performed efficiently. Further, by moving all the carriages 70 at a constant cycle, the variation in temperature drop of the carriages 70 can be reduced.

[0044] FIG. 8 is a diagram showing the cooling time of the recording head in the image recording apparatus 1 of the embodiment. The solid line in FIG. 8 shows the case where the image recording apparatus 1 moves the carriage 70 provided with the recording head 71 to be replaced, which is described in FIGS. 5 to 7B, to the carriage retracted position to cool the recording head 71, and the dotted line shows the case where this is not performed. By moving the carriage 70 to the carriage retracted position, the density of the carriage 70 is coarsened to cool the recording head 71, so that the cooling efficiency is improved and the cooling time until the temperature drops to a temperature at which the head can be replaced can be shortened.

[0045] Next, the control system of the image recording apparatus 1 of the embodiment will be described. FIG. 9 is a block diagram showing the configuration of the control unit 40. The control unit 40 of the image recording apparatus 1 includes a ROM that stores a program for controlling each component, a CPU that executes the program, and a RAM or the like that serves as a work area during program execution. The control unit 40 can execute the function of the carriage retraction control unit 401 described later by the process executed by the CPU based on the above program.

[0046] The control unit 40 is provided with an image memory circuit 42 that stores the formed image data input from a host computer as a higher-level device via an interface circuit 41. Then, based on the formed image data in the image memory circuit 42, the control unit 40 forms an ink image on the recording medium P. At this time, the control unit 40 controls in conjunction an ink heater 73 that heats the ink supplied to each recording head 71, a head drive circuit 74 that drives each recording head 71, and an irradiation unit 93 that irradiates the ink image formed on the recording medium P with UV rays.

[0047] Also, the control unit 40 controls a recording medium supply unit 10 that conveys the recording medium P to the image forming unit 20 and a drum rotation motor 53 that rotates the image forming drum 50, which are electrically connected via a predetermined interface, to control the conveyance of the recording medium P.

[0048] Furthermore, an operation panel 2 that displays various messages and accepts various operations from the user is electrically connected to the control unit 40 via a predetermined interface.

[0049] The carriage retraction control unit 401 of the control unit 40 controls a Y carriage drive unit 75, an M carriage drive unit 76, a C carriage drive unit 77, a K carriage drive unit 78, and a cooling fan 98 that air-cools each carriage 70. Then, the carriage retraction control unit 401 moves the carriage 70 provided with the head to be replaced designated by the operation panel 2 to the carriage retraction position and cools it until it reaches a temperature at which the head can be replaced, as described with reference to FIGS. 5 to 7B. The Y carriage drive unit 75 drives the yellow (Y) carriage 70 in the X direction. The M carriage drive unit 76 drives the magenta (M) carriage 70 in the X direction. The C carriage drive unit 77 drives the cyan (C) carriage 70 in the X direction. The K carriage drive unit 78 drives the black (K) carriage 70 in the X direction.

[0050] Specifically, when starting the head replacement process, the control unit 40 first turns off the heating of the ink by the ink heater 73 and also turns off the head heater. Then, the control unit 40 detects the temperature of the recording head 71 using the Y head temperature detection unit 751, the M head temperature detection unit 761, the C head temperature detection unit 771, and the K head temperature detection unit 781. And the control unit 40 moves the carriage 70 to the carriage retracted position as described above by the carriage retraction control unit 401 until the detected temperature of the recording head 71 drops to a predetermined temperature at which the head can be replaced, and air-cools the carriage 70 using the cooling fan 95. That is, by air-cooling the carriage 70, the recording head 71 is cooled. In this specification, the Y head temperature detection unit 751, the M head temperature detection unit 761, the C head temperature detection unit 771, and the K head temperature detection unit 781 are collectively referred to as the head temperature detection unit.

[0051] The cooling fan 95 ventilates the cooling air along the moving direction (X direction) of each carriage 70 to air-cool each carriage 70. By moving the carriage 70 as described in FIGS. 5 to 7B, the interval between adjacent carriages 70 becomes wider, so that the cooling air can ventilate more easily, the cooling efficiency is improved, and the cooling time until the temperature drops to a temperature at which the head can be replaced can be shortened.

[0052] Next, the operation of the control unit 40 will be described with reference to the flowchart of FIG. 10. In step S1, the control unit 40 acquires information specifying the replacement head designated on the head replacement screen (see FIG. 11) displayed on the operation panel 2. Although detailed description is omitted, on the head replacement screen of FIG. 11, all the recording heads 71 of each carriage 70 of the image recording apparatus 1 are schematically displayed, and the user touches and designates all the recording heads 71 to be replaced on the screen. Then, the control unit 40 turns off the ink heater 73 and the head heater, turns on the cooling fan, and sets the heat dissipation operation of the carriage 70.

[0053] In step S2, the carriage retraction control unit 401 determines whether it is one of the heads to be replaced. If it is one (Yes in S2), it proceeds to step S4. If it is not one (No in S2), it proceeds to step S3.

[0054] In step S3, the carriage retraction control unit 401 determines whether a plurality of heads to be exchanged are provided on the same carriage. Then, if they are provided on the same carriage (Yes in S3), the carriage retraction control unit 401 proceeds to step S4; if they are not on the same carriage (No in S3), it proceeds to step S7.

[0055] In step S4, as described with reference to FIG. 5, the carriage retraction control unit 401 moves only the carriage 70 provided with the head to be exchanged to the carriage retraction position. At this time, the control unit 40 forcibly air-cools the carriage. Specifically, if the head to be exchanged is the magenta (M) recording head 71, the carriage retraction control unit 401 moves the magenta (M) carriage 70 by the M carriage drive unit 76. Then, the control unit 40 drives the cooling fan 98. Similarly, for carriages of other colors, the carriage retraction control unit 401 moves them to the carriage retraction position, and the control unit 40 drives the cooling fan 98 to perform forced air-cooling.

[0056] In step S5, the control unit 40 detects the temperature of the recording head 71 to be exchanged by the head temperature detection unit, and determines whether the temperature of the recording head 71 has dropped to a predetermined temperature at which the head can be exchanged. Then, if it has dropped to the predetermined temperature (Yes in S5), the control unit 40 proceeds to step S6; if not (No in S5), it waits.

[0057] In step S6, the control unit 40 displays on the operation panel 2 that the head can be exchanged, and ends the process when it detects the completion of the exchange operation.

[0058] In step S7, as described with reference to FIGS. 6A and 6B, or FIGS. 7A and 7B, the carriage retraction control unit 401 divides each carriage 70 into two sets and alternately moves them between the printing operation position and the carriage retraction position at a predetermined cycle. At this time, the control unit 40 drives the cooling fan 98 for forced air cooling. The movement of each carriage 70 is performed by the Y carriage drive unit 75, the M carriage drive unit 76, the C carriage drive unit 77, and the K carriage drive unit 78.

[0059] In step S8, the control unit 40 detects the temperature of all the recording heads 71 to be replaced by the head temperature detection unit, and determines whether the temperature of the recording head 71 has dropped to a predetermined temperature at which the head can be replaced. Then, if the temperature has dropped to the predetermined temperature (Yes in S8), the carriage retraction control unit 401 proceeds to step S9; if not (No in S8), it returns to step S7.

[0060] In step S9, the control unit 40 sequentially moves the carriage 70 provided with the head to be replaced to the carriage retraction position by the carriage retraction control unit 401. Then, the control unit 40 displays on the operation panel 2 that the head can be replaced and monitors the completion of the replacement work. Then, when the control unit 40 detects the completion of the replacement work for all the carriages 70 provided with the heads to be replaced, the process ends.

[0061] In the flowchart of FIG. 10, an example is shown in which the control unit 40 cools the recording head 71 by separating the processing according to whether there is one carriage 70 or a plurality of carriages 70 provided with the heads to be replaced. However, even when there is one carriage, the carriage 70 may be cooled by steps S7 and S8, and the carriage 70 provided with the head to be replaced may be moved to the carriage retraction position by step S9 to perform head replacement.

[0062] Also, when there are a plurality of carriages 70 provided with the heads to be replaced, the carriage 70 is moved to the carriage retraction position for each carriage 70 provided with the head to be replaced (S4). Then, it waits until the carriage 70 drops to the predetermined temperature (S5), and head replacement may be performed.

Explanation of Symbols

[0063] 1 Image recording device 2 Operation panel 10 Recording medium supply unit 40 Control unit 401 Carriage retraction control unit 53 Drum rotation motor 70 Carriage 71 Recording head 73 Ink heater 75 Y carriage drive unit 751 Y head temperature detection unit 76 M carriage drive unit 761 M head temperature detection unit 77 C carriage drive unit 771 C head temperature detection unit 78 K carriage drive unit 781 K head temperature detection unit 98 Cooling fan

Claims

1. A plurality of carriages provided with a recording head for discharging ink and performing printing, and a control unit having a carriage retraction control unit for controlling the movement of the carriage between a printing position and a carriage retraction position where the recording head is exchanged. When exchanging the recording head, the control unit moves the carriage to the carriage retraction position by the carriage retraction control unit so that the distance between the carriage provided with the recording head to be exchanged and another carriage becomes wider. An image recording apparatus characterized by the above.

2. It includes a head temperature detection unit for obtaining the temperature of the recording head, and until the control unit detects by the head temperature detection unit that the temperatures of all the recording heads to be exchanged have dropped to a temperature at which the recording heads can be exchanged, the carriage retraction control unit moves the carriages in multiple groups and alternately moves the groups of carriages to the carriage retraction position. The image recording apparatus according to claim 1, characterized by the above.

3. When the control unit detects by the head temperature detection unit that the temperatures of all the recording heads to be exchanged have dropped to a temperature at which the recording heads can be exchanged, for each carriage provided with the head to be exchanged, the carriage retraction control unit sequentially moves the carriage provided with the recording head to be exchanged to the carriage retraction position. The image recording apparatus according to claim 2, characterized by the above.

4. When exchanging the recording head, it includes a cooling fan for ventilating cooling air between the carriage provided with the recording head to be exchanged and another carriage. The image recording apparatus according to claim 1, characterized by the above.

5. It includes an ink heater for heating the ink, and when exchanging the recording head, the control unit turns off the ink heater. The image recording apparatus according to claim 1, characterized in that...

6. comprising a head heater for heating the recording head, wherein the control unit turns off the head heater when the recording head is replaced. The image recording apparatus according to claim 1, characterized in that...

7. comprising an operation panel for displaying a message and designating a recording head to be replaced, wherein the control unit controls the movement of the carriage provided with the recording head to be replaced according to the user setting on the operation panel, and notifies the operation panel that the replacement operation is possible. The image recording apparatus according to claim 1, characterized in that...

8. wherein the carriage retraction position is a direction intersecting the conveyance direction of the recording medium. The image recording apparatus according to claim 1, characterized in that...

9. A method for cooling an image recording apparatus having a plurality of carriages provided with recording heads for discharging ink for printing, comprising: when replacing the recording head, a step of moving the carriage from the printing position to a carriage retraction position where the recording head is to be replaced, such that the distance between the carriage provided with the recording head to be replaced and another carriage is widened by a carriage retraction control unit; A method for cooling an image recording apparatus, characterized by including the above.

Images