Inkjet recording device

Abstract

The present invention provides an inkjet recording device that can reliably recover ink from within the cap portion without dripping ink from the cap portion to the outside when the cap portion is moved from the capped position to the uncapped position. [Solution] The inkjet recording device X1 comprises a recording head 3, a cap portion 91, an ink absorber 97, a head moving mechanism 12 capable of relatively moving the cap portion 91 between a capped position and an uncapped position, and a drive control unit 102. The drive control unit 102 drives the head moving mechanism 12 to move the cap portion 91, which is positioned at the capped position, to a position where a gap is formed between it and the ejection surface 31, and then moves the cap portion 91 back to the capped position.

Description

Technical Field

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[0001] The present invention relates to an inkjet recording apparatus.

Background Art

[0002] An inkjet recording apparatus that records an image on a sheet by an inkjet method includes a recording head in which a plurality of nozzles from which ink is ejected are formed on a ejection surface. The recording head ejects ink from the nozzles toward the sheet by applying a voltage to a piezoelectric element provided corresponding to each nozzle. Further, in an inkjet recording apparatus, due to an increase in the viscosity of the ink caused by drying of the ink or the like, the ejection amount of the ink from the nozzles may become unstable or the nozzles may be clogged. In this case, the image quality of a printed matter printed by the inkjet recording apparatus deteriorates. Therefore, in order to reduce drying of the ink in the nozzles, when the inkjet recording apparatus is not in use, the nozzles are capped by a cap portion.

[0003] Conventionally, in order to remove ink dripping from a cap, a cap holder having a guiding member for receiving the ink and a discharge path for discharging the received ink is known (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004] [[ID=​​​​​​​​​​​​​However, conventional cap mechanisms consist of a cap and a cap holder, and without the cap holder, it is impossible to remove the ink (waste liquid) that drips from the cap. Furthermore, a discharge path is required to discharge the ink guided by the guide member, making the cap mechanism extremely complex. In addition, with conventional cap mechanisms, ink with low fluidity does not move smoothly from the guide member to the discharge path, so the ink remains inside the cap, and if the cap is moved to the uncapped position in this state, the ink will drip from the cap.

[0006] The object of the present invention is to provide an inkjet recording device that can reliably recover the ink inside the cap portion without dripping the ink accumulated in the cap portion to the outside when the cap portion is moved from the capped position to the uncapped position. [Means for solving the problem]

[0007] An inkjet recording apparatus according to one aspect of the present invention comprises: a recording head having a plurality of nozzles on its discharge surface from which ink is ejected; a cap portion for covering the plurality of nozzles; an ink absorber provided on the outer peripheral wall of the cap portion; a first movement mechanism capable of moving the cap portion relative to the recording head between a cap position where the cap end of the outer peripheral wall of the cap portion abuts the discharge surface and an uncapped position where the cap end is separated from the discharge surface by a predetermined distance; and a drive control unit for controlling the position of the cap portion. The drive control unit drives the first movement mechanism to move the cap portion, which is positioned at the cap position, to a close position where a distance shorter than the predetermined distance is formed between it and the discharge surface, and then moves the cap portion to the cap position. [Effects of the Invention]

[0008] According to the present invention, when the cap portion is moved from the capped position to the uncapped position, it is possible to reliably recover the ink accumulated in the cap portion without dripping the ink to the outside, despite the simple configuration. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 shows the configuration of an inkjet recording apparatus according to an embodiment of the present invention. [Figure 2] Figure 2 shows a recording head and cap device according to an embodiment of the present invention. [Figure 3] Figure 3 shows the state in Figure 2 where the recording head is positioned in the maintenance location. [Figure 4] Figure 4 shows the state in Figure 3 where the cap portion of the cap device is positioned in the cap setting position. [Figure 5] Figure 5 shows the state in Figure 4 where the recording head is capped by the cap portion of the capping device. [Figure 6] Figure 6 shows the configuration of the cap portion of an inkjet recording apparatus according to an embodiment of the present invention. [Figure 7] Figure 7 is a block diagram showing the configuration of an inkjet recording apparatus according to an embodiment of the present invention. [Figure 8] Figure 8 is a flowchart showing an example of the procedure for a purging operation performed in an inkjet recording apparatus according to an embodiment of the present invention. [Figure 9] Figure 9 is a flowchart showing an example of the procedure for ink recovery processing performed by the control unit of an inkjet recording apparatus according to an embodiment of the present invention. [Figure 10] Figure 10 is a schematic diagram illustrating the operation of the cap during the ink recovery process. [Figure 11] Figure 11 is a schematic diagram illustrating another example of the operation of the cap during the ink recovery process. [Figure 12]FIG. 12 is a diagram showing another configuration of the cap portion of the cap device. [Figure 13] FIG. 13 is a flowchart showing another example of the procedure of the ink recovery process executed by the control unit of the inkjet recording apparatus according to an embodiment of the present invention. [Figure 14] FIG. 14 is a flowchart showing another example of the procedure of the ink recovery process executed by the control unit of the inkjet recording apparatus according to an embodiment of the present invention. [Figure 15] FIG. 15 is a diagram showing another configuration of the cap portion of the inkjet recording apparatus according to an embodiment of the present invention. [Figure 16] FIG. 16 is a diagram showing another configuration of the cap portion of the cap device.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are merely examples embodying the present invention and do not limit the technical scope of the present invention.

[0011] [Configuration of Inkjet Recording Apparatus X1] First, referring to FIG. 1, the configuration of an inkjet recording apparatus X1 (hereinafter abbreviated as "recording apparatus X1") according to an embodiment of the present invention will be described. The recording apparatus X1 is a printer capable of printing an image on a sheet-like recording medium based on an inkjet method. Here, FIG. 1 is a diagram schematically showing the internal configuration of the recording apparatus X1.

[0012] The present invention may also be applied to apparatuses such as a facsimile apparatus, a copying machine, and a multifunction machine capable of执行 printing processing by an inkjet method.

[0013] As shown in FIG. 1, the recording apparatus X1 includes a paper feed cassette 1, a paper feed unit 2, a recording head 3 (an example of the recording head of the present invention), an ink container unit 4, a conveyance unit 5, a paper discharge unit 6, a purge device 8, a cap device 9, and a housing 11 (apparatus main body) that houses or supports these components.

[0014] The paper feed cassette 1 is provided at the lower part of the recording device X1. The paper feed cassette 1 houses sheets (recording media) to be printed in the recording device X1. For example, the sheets housed in the paper feed cassette 1 are sheet materials such as paper, coated paper, postcards, envelopes, cloth, OHP sheets, etc.

[0015] The paper feed unit 2 supplies the sheets housed in the paper feed cassette 1 to the recording head 3. The paper feed unit 2 has a pickup roller that abuts on the upper surface of the sheet and is rotationally driven, a feed roller that rotates by receiving a driving force from a driving source such as a motor, and a driven roller that is pressed against and driven by the feed roller. The pickup roller takes out sheets from the paper feed cassette 1 one by one. The feed roller conveys the sheet taken out by the pickup roller to the recording head 3.

[0016] Inside the housing 11, a vertical conveyance path 7A extending upward from the paper feed unit 2 is formed. The sheet fed by the paper feed unit 2 is conveyed upward along the conveyance direction D1 through the vertical conveyance path 7A.

[0017] The recording head 3 records an image on the sheet supplied from the paper feed unit 2. As shown in FIG. 1, the recording head 3 is provided above the paper feed unit 2. The recording head 3 has four head parts corresponding to each color of black, cyan, magenta, and yellow. Note that the number of the head parts provided in the recording head 3 may be one or a plurality.

[0018] As shown in FIG. 2, the recording head 3 has a plurality of nozzles 32 from which ink is ejected. The plurality of nozzles 32 are formed on the ejection surface 31 of the recording head 3.

[0019] As shown in FIG. 1, in the present embodiment, the recording head 3 is inclined with respect to the vertical direction. Specifically, the ejection surface 31 of the recording head 3 is inclined with respect to the vertical direction.

[0020] The recording head 3 ejects ink toward the sheet being transported by the transport belt 51 of the transport unit 5. The ejection surface 31 of the recording head 3 (see Figure 2) has a number of nozzles 32 for ejecting ink, each having an opening. The ejection surface 31 is the surface of the recording head 3 that faces the transport belt 51, or in other words, the surface that faces the recording surface of the sheet being transported by the transport unit 5.

[0021] The recording head 3 includes a plurality of pressurized chambers (not shown) corresponding to each nozzle 32, a plurality of piezoelectric elements provided corresponding to each pressurized chamber, and a communication channel (not shown) communicating with each pressurized chamber. The piezoelectric elements eject ink from the nozzles 32 in response to the input of a predetermined drive signal (control signal). For example, the drive signal is a clock signal with predetermined voltage, frequency, and duty cycle. Specifically, the piezoelectric elements eject ink from the nozzles 32 by pressurizing the ink contained in the pressurized chambers.

[0022] As shown in Figure 1, the ink container section 4 comprises ink containers 41, 42, 43, and 44, each containing ink corresponding to black, cyan, magenta, and yellow. The ink containers 41 to 44 are connected to the print head section of the same color via an ink supply section (not shown). Ink is supplied to the print head section from each of the ink containers 41 to 44.

[0023] The transport unit 5 is positioned opposite the ejection surface 31 of the recording head 3. The transport unit 5 transports the sheet while keeping the recording surface (top surface) of the sheet facing the ejection surface 31 of the recording head 3.

[0024] As shown in Figure 1, in this embodiment, the transport unit 5 is inclined with respect to the vertical, similar to the recording head 3. More specifically, the sheet support surface of the transport belt 51 facing the recording head 3 is inclined with respect to the vertical at approximately the same angle as the discharge surface 31.

[0025] The transport unit 5 includes a transport belt 51 on which the sheet is supported, tension rollers 52 and 53 that tension the transport belt 51, and a transport frame (not shown) that supports them. The gap formed between the transport belt 51 and the discharge surface 31 is adjusted, for example, so that the gap between the recording surface of the sheet and the discharge surface 31 during the printing process is 1 mm.

[0026] The conveyor belt 51 is an endless, annular belt. The tension rollers 52 and 53 are positioned inside the conveyor belt 51.

[0027] The tension roller 52 is connected to the rotating shaft of a motor (not shown). When the tension roller 52 is rotated clockwise by the motor, the conveyor belt 51 rotates in a direction that allows the sheet to be conveyed in the conveying direction D1. As a result, the sheet supplied from the paper feeding unit 2 is conveyed by the rotation of the conveyor belt 51 through the recording head 3 toward the paper discharge unit 6.

[0028] Furthermore, the transport unit 5 is equipped with a suction unit (not shown) that draws in air from numerous through holes (not shown) formed in the transport belt 51 in order to attract the sheet to the transport belt 51.

[0029] As shown in Figure 1, a discharge passage 7B is formed inside the housing 11, extending upward from the transport unit 5. The sheet, transported in the transport direction D1 by the transport unit 5, is transported upward along the transport direction D1 through the vertical transport passage 7A.

[0030] The paper discharge unit 6 is located downstream of the recording head 3 in the transport direction D1. The paper discharge unit 6 is a transport roller pair consisting of a drive roller and a driven roller. Sheets on which images have been recorded by the recording head 3 are discharged into the paper discharge tray 15 by the paper discharge unit 6.

[0031] As shown in Figure 7, the recording device X1 further comprises a control unit 10, a head movement mechanism 12 (an example of the first movement mechanism of the present invention), a cap movement mechanism 13 (an example of the second movement mechanism of the present invention), and a temperature sensor 14 (an example of the information acquisition unit of the present invention).

[0032] The control unit 10 drives the head movement mechanism 12 to control the movement of the recording head 3 to a predetermined position. The control unit 10 also drives the cap movement mechanism to control the movement of the cap device 9 to a predetermined position.

[0033] The temperature sensor 14 is a sensor that detects the temperature of the air in the internal space of the recording device X1. This temperature affects the viscosity of the ink and is an example of environmental information in the present invention. The temperature sensor 14 is connected to the control unit 10, and the temperature is detected by the control unit 10. In this embodiment, the temperature is used as an example of environmental information that affects the viscosity of the ink, but the environmental information in the present invention is not limited to this temperature. Other examples of the environmental information may include, for example, the humidity inside or outside the recording device X1, or weather information of the area where the recording device X1 is installed. The humidity can be detected by a humidity sensor. The weather information can be obtained, for example, from a website that provides weather information when the recording device X1 is connected to a communication network such as the Internet.

[0034] The head movement mechanism 12 supports the recording head 3 so that it can move in a direction D2 perpendicular to the belt surface of the conveyor belt 51. The head movement mechanism 12 can be a well-known mechanism consisting of a motor, rack and pinion gear, slide rail, position sensor, etc.

[0035] The head movement mechanism 12 moves the recording head 3, thereby moving the recording head 3 away from the transport unit 5 or bringing the recording head 3 closer to the transport unit 5. Specifically, the head movement mechanism 12 moves the recording head 3 between a recording position (shown in Figure 2) where printing by the recording head 3 is possible in close proximity to the transport belt 51, and a maintenance position (shown in Figure 3) at a predetermined distance from the transport belt 51.

[0036] Figure 2 shows the state in which the recording head 3 is positioned at the recording position closest to the transport unit 5. When the recording head 3 is in this recording position, the recording device X1 is capable of printing.

[0037] Figure 3 shows the recording head 3 retracted to the maintenance position, which is furthest from the transport unit 5. When the recording head 3 is in this maintenance position, the user can remove jammed sheets from the transport unit 5. Also, when the recording head 3 is in the maintenance position, the capping device 9 can perform capping to cover the nozzle 32 on the discharge surface 31, and the purging device 8 can perform purging (nozzle recovery).

[0038] The capping device 9 is located below the recording head 3. Under normal circumstances (during printing), the capping device 9 is positioned in a standby position below the recording head 3 (see Figure 3).

[0039] The capping device 9 is a device for covering the nozzles 32 on the ejection surface 31 of the recording head 3 when not printing, in order to prevent the ink inside the nozzles 32 from drying out. As shown in Figure 2, the capping device 9 has a cap portion 91 that covers the nozzles 32 on the ejection surface 31. The cap portion 91 is supported by a cap moving mechanism 13 (see Figure 7) so as to be movable between the standby position below the recording head 3 (see Figure 3) and a predetermined capping position (an example of the non-capping position in the present invention, see Figure 4). The capping position is a position defined in the space between the recording head 3 and the transport unit 5 located in the maintenance position (see Figure 4), and is a position that is pre-positioned when capping the nozzles 32. In other words, the capping position is a position facing the ejection surface 31, and the cap portion 91 of the capping device 9 is a predetermined distance away from the ejection surface 31.

[0040] The cap moving mechanism 13 is configured to move the cap portion 91 in a sliding direction along the discharge surface 31. The cap moving mechanism 13 supports the cap device 9 so that it can move between the standby position (see Figure 3) and the cap set (see Figure 4). As the cap moving mechanism 13, a well-known mechanism consisting of a motor, rack and pinion gear, slide rail, position sensor, etc., is applied.

[0041] The control unit 10 moves the cap device 9 between the standby position and the cap set position by driving the cap moving mechanism 13.

[0042] When an instruction to perform a capping operation is input, or when the operating conditions for performing a capping operation are met, the control unit 10 drives the head moving mechanism 12 to move the recording head 3 from the recording position (see Figure 2) to the maintenance position (see Figure 3). Furthermore, the control unit 10 drives the cap moving mechanism 13 to move the capping device 9 from the standby position (see Figure 3) to the capping position (see Figure 4).

[0043] With the capping device 9 positioned in the capping set position, the control unit 10 drives the head moving mechanism 12 to move the recording head 3 toward the transport unit 5. As a result, the cap portion 91 of the capping device 9 approaches the discharge surface 31, and the cap end portion 92 (an example of the cap end portion of the present invention) of the outer peripheral wall 91B of the cap portion 91 comes into contact with the discharge surface 31 and is pressed against it. As a result, as shown in Figure 5, the nozzle 32 is covered by the cap portion 91, and the nozzle 32 is capped. The position of the capping device 9 at this time is referred to as the capping position.

[0044] When the capping device 9 is positioned at the capping location, all nozzles 32 on the discharge surface 31 are airtightly covered by the cap portion 91. Hereinafter, the state in which the discharge surface 31 is airtightly covered by the cap portion 91 will be referred to as the capping state.

[0045] Figure 6 shows the configuration of the cap portion 91. The left side of Figure 6 shows a central cross-sectional view of the cap portion 91, and the right side of Figure 6 shows a rear view of the cap portion 91. As shown in Figure 6, the cap portion 91 has a rectangular base plate 91A and an outer peripheral wall 91B that protrudes perpendicularly from the outer circumference of the base plate 91A. The base plate 91A and the outer peripheral wall 91B form the internal space of the cap portion 91.

[0046] Furthermore, a communication hole 94 is formed at the upper end of the center in the longitudinal direction of the base plate 91A. Also, a suction hole 93 is formed at the lower end of the center in the longitudinal direction of the base plate 91A.

[0047] The cap portion 91 is provided with an ink absorber 97 capable of absorbing ink. The ink absorber 97 is provided on the outer peripheral wall 91B of the cap portion 91. More specifically, the ink absorber 97 is attached to the outer surface of the lower outer peripheral wall 91B1, which is located on the lower side of the outer peripheral wall 91B.

[0048] The ink absorber 97 is formed in a narrow rectangular parallelepiped shape. The ink absorber 97 is attached to the outer surface of the lower outer peripheral wall 91B1 over the entire area from the cap end 92 to the base plate 91A. In this embodiment, the ink absorber 97 is attached to the outer surface of the lower outer peripheral wall 91B1 with its end 97A aligned with the cap end 92 of the lower outer peripheral wall 91B1.

[0049] The purging device 8 is a device for restoring the function of the recording head 3. As shown in Figure 2, the purging device 8 includes an electric purging pump 81 for sucking ink out of the nozzles 32 of the recording head 3, a pressure chamber 82, a connecting tube 83, and a suction tube 84.

[0050] The purge pump 81 is connected to the pressure chamber 82 by a connecting tube 83. One end of the suction tube 84 is connected to the pressure chamber 82, and the other end is connected to a suction hole 93 formed in the cap portion 91.

[0051] When the purge pump 81 is activated, the air inside the pressure chamber 82 is drawn in, creating negative pressure inside the pressure chamber 82, and the air inside the cap portion 91 is drawn in via the suction tube 84. At this time, if ink is present inside the cap portion 91, the ink is also drawn in along with the air.

[0052] The purge pump 81 is electrically connected to the control unit 10, operates in response to a drive signal output from the control unit 10, and stops when the drive signal is interrupted.

[0053] The connecting tube 83 is equipped with a check valve 83A to prevent backflow from the purge pump 81 to the pressure chamber 82. The suction tube 84 is also equipped with a check valve 84A to prevent backflow from the pressure chamber 82 to the cap portion 91.

[0054] When an instruction to perform a purge operation is input, or when the operating conditions for performing a purge operation are met, the control unit 10 drives the head moving mechanism 12 and the cap moving mechanism 13 to put the nozzle 32 into the capping state with the cap portion 91. After that, the control unit 10 executes the purge process. Specifically, the control unit 10 drives the purge pump 81 (see Figure 2) to create negative pressure in the internal space of the cap portion 91, and discharges ink from the nozzle 32 of the recording head 3. The ink discharged from the nozzle 32 moves to the suction hole 93 due to gravity acting on the ink and the suction force from the suction hole 93, flows from the suction hole 93 through the suction tube 84 into the pressure chamber 82, and is held in the absorbent material provided in the pressure chamber 82.

[0055] This purging process discharges any high-viscosity ink remaining in each nozzle 32 of the discharge surface 31, thereby resolving any clogging of the nozzles 32.

[0056] Incidentally, when the ejection surface 31 of the recording head 3 is capped by the cap portion 91, ink may accumulate inside the cap portion 91. Also, when the purging operation is performed, ink may remain inside the cap portion 91 after the purging process. In particular, as shown in Figure 5, in the capped state, wedge-shaped residual ink P1 (see Figure 5) may remain stuck to the corner between the inner surface of the lower outer peripheral wall 91B1 and the ejection surface 31. Such residual ink P1 is likely to occur when the recording head 3 is positioned so that the ejection surface 31 is vertical, or when the ejection surface 31 is inclined with respect to the vertical, as in this embodiment. If the cap portion 91 is released from the capped state while residual ink P1 remains inside the cap portion 91, the residual ink P1 will drip from the cap portion 91 and contaminate the inside of the recording device X1 with ink.

[0057] In this embodiment, as will be described later, the control unit 10 performs an ink recovery process (see Figure 9), so that even when the capping state is changed to the non-capping state, the ink accumulated in the cap portion 91 can be reliably recovered into the ink absorber 97 without dripping the ink into the cap portion 91.

[0058] The configuration of the control unit 10 will be described below with reference to Figure 7. Figure 7 is a block diagram showing the configuration of the control unit 10 of the recording device X1.

[0059] The control unit 10 comprehensively controls the recording device X1. The control unit 10 includes control devices such as a CPU, ROM, and RAM (not shown). The CPU is a processor that performs various arithmetic operations. The ROM is a non-volatile storage unit in which information such as control programs for causing the CPU to perform various operations is pre-stored. The RAM is a volatile storage unit used as a temporary storage memory (work area) for the various operations performed by the CPU. In the control unit 10, the CPU executes the various control programs pre-stored in the ROM. As a result, the recording device X1 is controlled by the control unit 10.

[0060] As shown in Figure 7, the control unit 10 includes a storage unit 101, a drive control unit 102, a cap processing unit 103, a recovery processing unit 104, a set time correction unit 105, and the like.

[0061] The memory unit 101 is a non-volatile memory device. The memory unit 101 stores data, information, and numerical values ​​used in various processes performed by the CPU and other components of the control unit 10. Specifically, the memory unit 101 stores information about the set time T1 used in the ink recovery process (see Figure 9) performed by the drive control unit 102, which will be described later.

[0062] The capping unit 103 performs the capping process. Specifically, when an instruction to perform a capping operation is input to the capping unit 103, or when the operating conditions for performing a capping operation are met, the capping unit 103 drives the head moving mechanism 12 to move the recording head 3 from the recording position (see Figure 2) to the maintenance position (see Figure 3). Then, the capping unit 103 drives the cap moving mechanism 13 to move the capping device 9 from the standby position (see Figure 3) to the capping set position (see Figure 4). After that, with the capping device 9 positioned in the capping set position, the capping unit 103 drives the head moving mechanism 12 to move the recording head 3 toward the transport unit 5. As a result, the nozzle 32 is capped by the capping unit 91.

[0063] The recovery processing unit 104 performs a purge operation. Specifically, when an instruction to perform a purge operation is input, or when the operating conditions for performing a purge operation are met, the recovery processing unit 104 drives the purge pump 81 (see Figure 2) to create negative pressure in the internal space of the cap portion 91, thereby discharging ink from the nozzle 32 of the recording head 3, while the nozzle 32 is capped by the cap portion 91 (capping state) by the cap processing unit 103. The ink discharged from the nozzle 32 moves to the suction hole 93 by the suction force of the purge pump 81, flows from the suction hole 93 through the suction tube 84 into the pressure chamber 82, and is held in the absorbent material provided in the pressure chamber 82.

[0064] The drive control unit 102 controls the position of the cap portion 91. Specifically, the drive control unit 102 drives the head moving mechanism 12 to move the cap portion 91, which is positioned at the cap position, to a close position (shown in Figure 10(B)) where a predetermined gap is formed between it and the discharge surface 31, and then moves the cap portion 91 back to the cap position. In this embodiment, after the purging process by the recovery processing unit 104 is performed with the cap portion 91 capping the nozzle 32, the drive control unit 102 moves the position of the cap portion 91 from the cap position to the close position, and then returns the cap portion 91 to the cap position.

[0065] The aforementioned proximity position is a position where the gap between the discharge surface 31 and the cap end 92 of the cap portion 91 is a minute gap of several millimeters. This minute gap is set to a distance that allows residual ink P1 (see Figure 5) to move into the minute gap by capillary action.

[0066] After the ink has moved into the minute gap, when the cap portion 91 is returned to its original cap position, the ink in the minute gap overflows to the outside of the cap portion 91, is absorbed by the ink absorber 97, and the ink is recovered by the ink absorber 97.

[0067] In this embodiment, the drive control unit 102 moves the cap portion 91 to the cap position after a predetermined set time T1 has elapsed since moving the cap portion 91 to the proximity position. The set time T1 is set to a time equivalent to the time required for the ink to move into the minute gap.

[0068] The setting time correction unit 105 performs a process to correct the setting time T1 based on the temperature detected by the temperature sensor 14 (detected temperature). Specifically, if the detected temperature is within a predetermined tolerance range, the setting time correction unit 105 maintains the setting time T1 at the initial setting value.

[0069] Furthermore, if the detected temperature is above the upper limit temperature within the allowable range, the setting time correction unit 105 corrects the setting value of the setting time T1 to a time shorter than the initial setting value. The higher the detected temperature, the lower the viscosity of the ink, so the time required for the ink to move into the minute gap is shorter than the initial setting value of the setting time T1. For this reason, the setting time correction unit 105 corrects the setting time T1 to a time obtained by multiplying the initial setting value by a reduction rate corresponding to the temperature difference between the detected temperature and the upper limit temperature, for example.

[0070] Furthermore, if the detected temperature is below the lower limit temperature within the allowable range, the setting time correction unit 105 corrects the setting value of the setting time T1 to a longer time than the initial setting value. The lower the detected temperature, the higher the viscosity of the ink, so the time required for the ink to move into the minute gap is longer than the initial setting value of the setting time T1. For this reason, the setting time correction unit 105 corrects the setting time T1 to a time obtained by multiplying the initial setting value by an increase rate corresponding to the temperature difference between the detected temperature and the lower limit temperature, for example.

[0071] The following describes an example of the procedure for a purge operation performed by the inkjet recording device X1, with reference to the flowcharts in Figures 8 and 9.

[0072] As shown in Figure 8, when an instruction to perform a purge operation is input, or when the operating conditions for performing a purge operation are met, the control unit 10 executes the capping process in step S1. Subsequently, the control unit 10 executes the purge process in step S2.

[0073] Once the purging process is performed, in the next step S3, the control unit 10 performs the ink recovery process described later.

[0074] Subsequently, in step S4, the control unit 10 performs a decapping process to separate the cap portion 91 from the ejection surface 31. In the decapping process, the control unit 10 moves the recording head 3 to move it relative to the cap position from the cap position to the cap set position. After that, the control unit 10 returns the capping device 9 from the cap set position to the maintenance position. Furthermore, the control unit 10 moves the recording head 3 to the recording position to return it to a printable state.

[0075] As shown in Figure 9, in the ink recovery process of step S3, the control unit 10 first moves the recording head 3 to the proximity position after the purging process in step S31.

[0076] In the next step S32, the control unit 10 determines whether the elapsed time since the recording head 3 moved to the proximity position has exceeded the set time T1.

[0077] If it is determined in step S32 that the set time T1 has elapsed, in step S33 the control unit 10 moves the recording head 3 to the cap position.

[0078] Thus, in this embodiment, since the ink recovery process is performed in the recording device X1, as shown in Figure 10(A), even if residual ink P1 remains in the corner between the discharge surface 31 and the lower outer peripheral wall 91B1 after the purging process, when the recording head 3 is moved to the proximity position, the residual ink P1 moves by capillary action into the gap between the discharge surface 31 and the cap end 92 (see Figure 10(B)). Subsequently, when the recording head 3 is returned to the cap position, the residual ink P1 that has entered the gap is pushed out to the outside of the lower outer peripheral wall 91B1, and the residual ink P1 is absorbed into the ink absorber 97 from the end 97A of the ink absorber 97 (see Figure 10(C)).

[0079] As a result, even when the capped state is changed to the uncapped state, the residual ink P1 accumulated in the cap portion 91 can be reliably absorbed and recovered by the ink absorber 97 without dripping out.

[0080] In the above-described embodiment, the recording head 3 is shown as being moved in a direction perpendicular to the conveyor belt 51 of the conveyor unit 5 as an example of a configuration in which the recording head 3 is moved between the cap position and the proximity position. However, the present invention is not limited to such a configuration. For example, as shown in Figures 11(A) and (B), the recording head 3 may be supported so as to be rotatable around a pivot axis 3A provided on its upper side. In this case, the head moving mechanism 12 supports the recording head 3 so as to be rotatable with the pivot axis 3A as the pivot point, and rotates the recording head 3 relative to the cap portion 91 to move it from the cap position where the cap end 92 of the lower outer peripheral wall 91B1 and the discharge surface 31 are in contact to the proximity position where the cap end 92 of the lower outer peripheral wall 91B1 and the discharge surface 31 are separated by the gap.

[0081] By applying this configuration, the gaps other than the gap between the cap end 92 and the discharge surface 31 of the lower outer peripheral wall 91B1 become smaller, making it more difficult for residual ink P1 to enter the other gaps, and making it easier for residual ink P1 to move into the gap between the cap end 92 and the discharge surface 31. As a result, residual ink P1 can be absorbed by the ink absorber 97 more reliably.

[0082] Furthermore, as shown in Figures 12(A) to (C), an expandable member 91C may be provided in the cap portion 91 to close the other gap when the recording head 3 moves from the cap position to the proximity position. This expandable member 91C is a rubber member inserted into a perforation formed in the other cap end 92 of the lower outer peripheral wall 91B1, other than the cap end 92. In the capped state, it is compressed within the perforation, and in the uncapped state, it expands from the perforation. When the recording head 3 moves from the cap position to the proximity position by the head movement mechanism 12, the expandable member 91C extends into the other gap, closing it to prevent residual ink P1 from entering the other gap.

[0083] Furthermore, in another embodiment of the ink recovery process described above (see Figure 9), instead of keeping the set time T1 constant regardless of the temperature of the recording device X1, the set time T1 may be changed, for example, according to the ambient temperature inside the recording device X1.

[0084] Specifically, as shown in Figure 13, the control unit 10 first determines in step S301 whether the temperature detected by the temperature sensor 14 is within the acceptable range.

[0085] If, in step S301, the detected temperature is determined to be within the acceptable range, the processes from step S31 onward are executed.

[0086] On the other hand, if in step S301 the detected temperature is determined to be outside the allowable range, in the next step S302 the control unit 10 determines whether the detected temperature is above the upper limit temperature of the allowable range. If the detected temperature is determined to be above the upper limit temperature, in the next step S303 the control unit 10 corrects the set time T1 to a time shorter than the initial setting value. This reduces unnecessary waiting time by shortening the set time T1 when the ambient temperature inside the recording device X1 is high and the viscosity of the residual ink P1 is low.

[0087] Furthermore, if, in step S302, the detected temperature is determined to be not above the upper limit temperature, that is, below the lower limit temperature of the allowable range, then in the next step S304, the control unit 10 corrects the set time T1 to a time longer than the initial setting value. This ensures that, when the ambient temperature inside the recording device X1 is low and the viscosity of the residual ink P1 is high, extending the set time T1 provides sufficient time for the residual ink P1 to move into the gap between the cap end 92 and the ejection surface 31.

[0088] Furthermore, as another embodiment of the ink recovery process described above (see Figure 9), for example, as shown in Figure 14, in step S31, after the recording head 3 has been moved to the proximity position, the control unit 10 may drive the cap moving mechanism 13 to move the cap device 9 a predetermined distance in the same direction as the transport direction D1 (sliding direction) while the recording head 3 is positioned at the proximity position (S311). After the set time T1 has elapsed (S32), the control unit 10 returns the recording head 3 to the cap position (S33).

[0089] The travel distance of the cap device 9 is preferably, for example, a distance corresponding to the thickness of the lower outer peripheral wall 91B1.

[0090] As the cap device 9 is moved in this manner, as shown in Figure 15(A), residual ink P1 can easily move from the cap end 92 of the lower outer peripheral wall 91B1 to the end 97A of the ink absorber 97. When the recording head 3 is returned to the cap position in this state, the residual ink P1 can be easily absorbed by the ink absorber 97 (see Figure 15(B)).

[0091] In the above embodiment, the cap portion 91 shown in Figure 6 was used as an example, but for example, the configuration of the cap portion 91 may be the configuration shown in Figure 16. Specifically, as shown in Figure 16, the cap portion 91 has a partition wall 98 in its internal space, and a housing space capable of housing the ink absorber 97 is formed between the partition wall 98 and the inner surface of the lower outer peripheral wall 91B1. The partition wall 98 forms an internal space that covers a plurality of nozzles 32 of the discharge surface 31 at the cap position, and also forms the housing space. In this embodiment, the ink absorber 97 is housed in the housing space between the partition wall 98 and the inner surface of the lower outer peripheral wall 91B1. With the cap portion 91 configured in this way, since the ink absorber 97 is located inside the lower outer peripheral wall 91B1 of the cap portion 91, even if ink seeps out from the ink absorber 97 that has absorbed residual ink P1, it is possible to prevent the ink from leaking to the outside of the cap portion 91.

[0092] Furthermore, in the above-described embodiment, a configuration was illustrated in which the recording head 3 is moved to the head moving mechanism 12 and the capping device 9 is moved relative to the discharge surface 31. However, it is also possible to apply a configuration in which, for example, the recording head 3 is positioned in the maintenance position and the capping device 9 is positioned in the cap setting position, and the capping device 9 is moved toward the discharge surface 31.

[0093] [Notes on the invention] The following is an overview of the invention extracted from the above-described embodiments. Note that each configuration and processing function described below can be selected and combined as desired.

[0094] <Note 1> A recording head having multiple nozzles on its ejection surface from which ink is ejected, A cap portion for covering the plurality of nozzles, An ink absorber provided on the outer peripheral wall of the cap portion, A first movement mechanism that allows the cap portion to move relative to the recording head between a cap position in which the cap end of the outer peripheral wall of the cap portion abuts the discharge surface and an uncapped position in which the cap end is separated from the discharge surface by a predetermined distance, The system includes a drive control unit that controls the position of the cap portion, The drive control unit drives the first moving mechanism to move the cap portion, which is positioned at the cap position, to a close position where a gap shorter than the predetermined gap is formed between it and the ejection surface, and then moves the cap portion back to the cap position, in an inkjet recording apparatus.

[0095] <Note 2> The inkjet recording apparatus according to Appendix 1, wherein the drive control unit moves the cap portion to the cap position after a predetermined set time has elapsed since moving the cap portion to the proximity position.

[0096] <Note 3> The inkjet recording apparatus according to Appendix 1 or 2, wherein the ejection surface of the recording head is inclined with respect to the vertical direction.

[0097] <Note 4> The ink absorber is provided on the lower outer peripheral wall of the outer peripheral wall of the cap portion, which is vertically lower, as described in Appendix 3 of the inkjet recording apparatus.

[0098] <Note 5> The inkjet recording apparatus according to Appendix 4, wherein the first moving mechanism moves the lower outer peripheral wall from the cap position to the proximity position by rotating the cap portion with the upper vertical side of the cap portion as the pivot point between the cap position and the proximity position.

[0099] <Note 6> The system further includes a second movement mechanism that allows the cap portion to move relative to the discharge surface in a sliding direction, The inkjet recording apparatus according to Appendix 5, wherein the drive control unit moves the cap portion from the cap position to the proximity position, then drives the second movement mechanism to move the cap portion a predetermined distance in the sliding direction, and then drives the first movement mechanism to move the cap portion to the cap position.

[0100] <Note 7> The inkjet recording apparatus as described in Appendix 6, wherein the predetermined distance is a distance corresponding to the thickness of the outer peripheral wall.

[0101] <Note 8> The ink absorber is attached to the outer surface of the outer peripheral wall of the cap portion of the inkjet recording apparatus according to any one of the appendices 1 to 7.

[0102] <Note 9> The cap portion forms an internal space that covers the plurality of nozzles at the cap position and has a partition wall that forms a housing space between it and the inner surface of the outer peripheral wall. The ink absorber is provided in the containment space of the inkjet recording apparatus according to any one of the appendices 1 to 8.

[0103] <Note 10> An information acquisition unit that acquires environmental information that affects the viscosity of the ink, An inkjet recording apparatus according to any one of the appendices 1 to 9, further comprising: a setting time correction unit that corrects the setting time based on the environmental information acquired by the information acquisition unit. [Explanation of Symbols]

[0104] 3: Recording head 5: Conveyor Unit 8: Purge device 9: Capping device 10: Control Unit 12: Head movement mechanism 13: Cap relocation mechanism 14: Temperature sensor 30: Recording head 31:Discharge surface 32: Nozzle 91A: Base plate 91B: Outer wall 91B1: Lower outer peripheral wall 91C: Expandable member 92: Cap end 93: Suction hole 94:Communication hole 97: Ink absorber 97A: End 98: Bulkhead 101: Storage section 102: Drive Control Unit 103: Cap Processing Unit 104: Recovery Processing Unit 105: Setting time correction unit

Claims

1. A recording head having multiple nozzles on its ejection surface from which ink is ejected, A cap portion for covering the plurality of nozzles, An ink absorber provided on the outer peripheral wall of the cap portion, A first movement mechanism that allows the cap portion to move relative to the recording head between a cap position in which the cap end of the outer peripheral wall of the cap portion abuts the discharge surface and an uncapped position in which the cap end is separated from the discharge surface by a predetermined distance, The system includes a drive control unit that controls the position of the cap portion, The drive control unit drives the first moving mechanism to move the cap portion, which is positioned at the cap position, to a close position where a gap shorter than the predetermined gap is formed between it and the ejection surface, and then moves the cap portion back to the cap position, in an inkjet recording apparatus.

2. The inkjet recording apparatus according to claim 1, wherein the drive control unit moves the cap portion to the cap position after a predetermined set time has elapsed since moving the cap portion to the proximity position.

3. The inkjet recording apparatus according to claim 1, wherein the ejection surface of the recording head is inclined with respect to the vertical direction.

4. The ink absorber is provided on the lower outer peripheral wall of the outer peripheral wall of the cap portion, which is vertically lower, according to claim 3.

5. The inkjet recording apparatus according to claim 4, wherein the first moving mechanism moves the lower outer peripheral wall from the cap position to the proximity position by rotating the cap portion with the upper vertical side of the cap portion as the pivot point between the cap position and the proximity position.

6. The system further includes a second movement mechanism that allows the cap portion to move relative to the discharge surface in a sliding direction, The inkjet recording apparatus according to claim 5, wherein the drive control unit moves the cap portion from the cap position to the proximity position, then drives the second movement mechanism to move the cap portion a predetermined distance in the sliding direction, and then drives the first movement mechanism to move the cap portion to the cap position.

7. The inkjet recording apparatus according to claim 6, wherein the predetermined distance is a distance corresponding to the thickness of the outer peripheral wall.

8. The ink absorber is attached to the outer surface of the outer peripheral wall of the cap portion, as described in claim 1.

9. The cap portion forms an internal space that covers the plurality of nozzles at the cap position and has a partition wall that forms a housing space between it and the inner surface of the outer peripheral wall. The inkjet recording apparatus according to claim 1, wherein the ink absorber is provided in the containment space.

10. An information acquisition unit that acquires environmental information that affects the viscosity of the ink, The inkjet recording apparatus according to claim 1, further comprising a setting time correction unit that corrects the setting time based on the environmental information acquired by the information acquisition unit.

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