Inkjet recording apparatus

Abstract

This inkjet recording device (100) comprises conveyance units (4a, 5, 12), recording heads (17a-17c), a cap member (30), cap movement mechanisms (65, 66), a control unit (110), a defect detection unit (110e), and a storage unit (28). The cap movement mechanisms (65, 66) are capable of moving the cap member (30) to a first position and a second position. The defect detection unit (110e) is capable of detecting occurrence of a movement obstruction factor. The storage unit (28) is capable of storing defect information including the movement obstruction factor. The control unit (110) is capable of executing a measurement mode in which defect information is stored in the storage unit (28) on the basis of a detection result of the defect detection unit (110e).

Description

Technical Field

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

Background Art

[0002] As a recording apparatus such as a facsimile machine, a copying machine, or a printer, an inkjet recording apparatus that discharges ink onto a recording medium such as paper or an OHP sheet to form an image is widely used because it can form a high-definition image.

[0003] In such an inkjet recording apparatus, when the solvent of the ink in the ink discharge nozzles provided in the recording head evaporates, the ink concentration increases, and clogging of the ink discharge ports at the tips of the ink discharge nozzles may occur. Therefore, in order to prevent the solvent of the ink in the ink discharge nozzles from evaporating, there is an inkjet recording apparatus provided with a cap for capping the ink discharge ports (Patent Document 1).

[0004] The inkjet recording apparatus of Patent Document 1 includes a rubber cap, a cap moving mechanism for moving the cap, and a control unit for controlling the cap moving mechanism. The cap has an annular rib protruding from the peripheral edge of the main body. The cap moving mechanism can move the cap between a first position separated from the ink discharge surface and a second position attached to the ink discharge surface. The cap moving mechanism suppresses drying of the ink discharge ports located inside the annular rib by pressing the annular rib of the cap against the ink discharge surface of the recording head. The control unit controls the cap moving mechanism so as to move the cap from the first position to the second position when a predetermined time has elapsed from when the ink is discharged from the ink discharge port until the next ink is discharged.

[0005] In addition, in order to prevent ink ejection failure due to drying or clogging of the recording head, the inkjet recording apparatus of Patent Document 1 performs a purge to extrude the ink with increased viscosity in the nozzle from the ejection nozzles of the recording head at the start of printing after a long-term stop or during the printing operation. The purge is also executed to forcibly extrude the ink from the ejection nozzles to eliminate clogging when clogging occurs at the ink ejection ports.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] By the way, in the inkjet recording apparatus as described above, due to various problems, there may be a case where the cap cannot be attached at the timing when the cap is normally attached to the ejection nozzles. In this case, the time during which the ink ejection ports are open becomes longer than normal, and the ink at the ink ejection ports is likely to dry. For this reason, the execution frequency of the above-described purge increases, which may lead to a decrease in productivity, such as a delay in the printing process or an increase in the ink consumption due to the purge.

[0008] Therefore, an object of the present invention is to provide an inkjet recording apparatus capable of suppressing a decrease in productivity.

Means for Solving the Problems

[0009] In order to achieve the above object, a first configuration of the present invention is an inkjet recording apparatus including a conveyance unit, a recording head, a cap member, a cap moving mechanism, and a control unit. The conveyance unit conveys a recording medium. The recording head has an ink ejection surface for ejecting ink, and performs printing processing by ejecting ink from the ink ejection surface onto the recording medium conveyed by the conveyance unit. The cap member is detachable from the ink ejection surface and protects the ink ejection surface. The cap moving mechanism is capable of moving the cap member between a first position separated from the ink ejection surface and a second position attached to the ink ejection surface. The control unit controls the cap moving mechanism to move the cap member from the first position to the second position at a cap closing timing when a predetermined time has elapsed after ink is ejected from the ink ejection surface until the next ink ejection. The inkjet recording apparatus includes a defect detection unit capable of detecting the occurrence of a movement inhibition factor that inhibits the movement of the cap member to the second position, and a storage unit capable of storing defect information including the movement inhibition factor. The control unit is capable of executing a measurement mode of storing the defect information in the storage unit based on the detection result of the defect detection unit.

Effects of the Invention

[0010] According to the first configuration of the present invention, it is possible to detect the occurrence of a movement inhibition factor of the cap member and store the defect information in the storage unit. Then, the user can perform maintenance of the inkjet recording apparatus based on the defect information stored in the storage unit, or review the operation method of the inkjet recording apparatus, the settings of the printing process, etc. Thereby, the occurrence of the movement inhibition factor of the cap member can be suppressed, and the frequency of executing the purge can be reduced. Therefore, it is possible to provide an inkjet recording apparatus capable of suppressing a decrease in productivity.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

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Figure 8

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Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the schematic configuration of an inkjet recording type printer 100 (inkjet recording apparatus) according to an embodiment of the present invention.

[0013] As shown in FIG. 1, the printer 100 is equipped with paper feed cassettes 2a, 2b and a manual feed tray 2c. Paper feed cassettes 2a, 2b can store paper P (recording media including printing paper, envelopes, etc.) inside. Paper feed cassettes 2a, 2b are provided at the bottom inside printer main body 1 (device main body). Paper P can be loaded on the top surface of manual feed tray 2c. Manual feed tray 2c is provided on the outside right side of printer main body 1. Hereinafter, the direction in which paper P is transported from paper feed cassettes 2a, 2b or manual feed tray 2c (the direction of arrow A in each drawing) will be referred to as the "paper transport direction". The paper transport direction and the up-down direction (arrow A in each drawing) will be referred to as the "paper transport direction". B - B ´ direction) (arrows in each drawing) C - C ´ direction) is referred to as the "paper width direction".

[0014] Paper feeders 3a and 3b are disposed downstream of the paper feed cassettes 2a and 2b in the paper transport direction, i.e., above the right side of the paper feed cassettes 2a and 2b in Fig. 1. Paper feeder 3c is disposed downstream of the manual feed tray 2c in the paper transport direction, i.e., to the left of the manual feed tray 2c in Fig. 1. Paper (recording medium) P is separated and fed one sheet at a time by the paper feeders 3a to 3c.

[0015] A body cover 51 is provided on the side of the printer body 1. The body cover 51 is supported by the printer body 1 so that it can rotate around a rotation shaft 52 provided at one end (here, the lower end) in the vertical or horizontal direction. The inside of the printer body 1 can be opened by rotating the body cover 51 in a direction away from the body cover 51. In this state, the user can access each device provided inside the printer body 1 (such as the maintenance unit 19 and recording unit 9 described below). The body cover 51 can be provided in multiple places on the printer body 1.

[0016] Around the main body cover 51, a cover opening / closing detection sensor 53 is provided. The cover opening / closing detection sensor 53 is a sensor capable of detecting the open / closed state of the main body cover 51. The cover opening / closing detection sensor 53 can employ an optical photosensor. In this case, the cover opening / closing detection sensor 53 has a light receiving part and a light emitting part (not shown). The cover opening / closing detection sensor 53 receives the light beam emitted from the light emitting part with the light receiving part, and can detect the open / closed state of the main body cover 51 from the light receiving state.

[0017] Also, inside the printer 100, a first paper conveyance path 4a (conveying part) is provided. The upstream end of the first paper conveyance path 4a in the paper conveyance direction is connected to the paper feed cassettes 2a, 2b via the paper feed devices 3a, 3b. The first paper conveyance path 4a extends upward along the side surface of the printer main body 1 from the upstream end in the paper conveyance direction. The manual paper feed tray 2c is connected to the first paper conveyance path 4a via the paper feed device 3c. The paper feed devices 3a, 3b feed the paper P from the paper feed cassettes 2a, 2b to the first paper conveyance path 4a. The paper feed device 3c feeds the paper P from the manual paper feed tray 2c to the first paper conveyance path 4a.

[0018] At the downstream end of the first paper conveyance path 4a with respect to the paper conveyance direction, a registration roller pair 13 is provided. Further, immediately downstream of the registration roller pair 13, a first belt conveyance part (conveying part) 5 and a recording part 9 are arranged. The registration roller pair 13 measures the timing with the ink ejection operation executed by the recording part 9 while correcting the skew feeding of the paper P, and sends out the paper P toward the first belt conveyance part 5.

[0019] Immediately upstream of the registration roller pair 13, a pre-registration sensor 20 for detecting the paper P sent out from the paper feed cassette 2a or the manual paper feed tray 2c is arranged. Also, between the registration roller pair 13 and the first belt conveyance part 5, a CIS (Contact Image Sensor) 21 for detecting the position of the end in the width direction (direction perpendicular to the paper conveyance direction) of the paper P is arranged.

[0020] The first belt conveyor unit 5 includes a first conveyor belt 8, a driving roller 6, and a driven roller 7. The first conveyor belt 8 is an endless belt. The driving roller 6 and the driven roller 7 are arranged side by side in the paper conveyance direction inside the first conveyor belt 8. The first conveyor belt 8 is wound around the driving roller 6 and the driven roller 7. The inner peripheral surface of the first conveyor belt 8 is in contact with the outer peripheral surface of the driving roller 6. When the driving roller 6 rotates, the first conveyor belt 8 rotates following the rotation of the driving roller 6.

[0021] A sheet suction portion 22 is provided at a position inside the first conveyor belt 8 and facing the back side of the conveyance surface of the first conveyor belt 8. The sheet suction portion 22 is provided with a large number of air suction holes on its upper surface (not shown), and includes a fan inside, and can suck air downward from the upper surface. Also, a large number of ventilation holes for air suction are provided in the first conveyor belt 8 (not shown). With the above configuration, the sheet P sent out from the resist roller pair 13 passes below the recording unit 9 while being adsorbed and held on the conveyance surface of the conveyor belt.

[0022] A sheet detection sensor 50 (recording medium detection sensor) is arranged around the recording unit 9. The sheet detection sensor 50 can detect the presence or absence of the sheet P between the recording unit 9 and the first conveyor belt 8 (the position where the sheet P faces the recording unit 9 vertically). When the printing process is interrupted, based on the detection result of the sheet detection sensor 50, it is possible to determine whether or not a paper jam has occurred between the recording unit 9 and the first conveyor belt 8.

[0023] A second belt conveyor unit 12 (conveyor unit) is arranged on the downstream side of the first belt conveyor unit 5 (the left side in FIG. 1) with respect to the paper conveyance direction. The sheet P on which an image has been recorded in the recording unit 9 is sent to the second belt conveyor unit 12, and the ink discharged onto the surface of the sheet P is dried while passing through the second belt conveyor unit 12. The configuration of the second belt conveyor unit 12 is the same as that of the first belt conveyor unit 5.

[0024] On the downstream side of the second belt conveyance unit 12 with respect to the paper conveyance direction, a second paper conveyance path 4b (conveyance unit) is provided. At the downstream end of the second paper conveyance path 4b with respect to the paper conveyance direction, a pair of discharge rollers 31 for discharging the paper P from the printer main body 1 is provided. When double-sided recording is not performed on the paper P, the paper P that has passed through the second belt conveyance unit 12 is discharged from the second paper conveyance path 4b through the pair of discharge rollers 31 to a paper discharge tray 15 provided outside the left side surface of the printer 100. When recording is performed on both sides of the paper P, after the recording on one side is completed and the paper P that has passed through the second belt conveyance unit 12 passes through the second paper conveyance path 4b, it is conveyed to the reverse conveyance path 16. The paper P sent to the reverse conveyance path 16 has its conveyance direction switched in order to reverse the front and back, passes through the upper part of the printer 100, and is conveyed to the registration roller pair 13. Then, it is conveyed again to the first belt conveyance unit 5 with the non-image-recorded surface facing upward.

[0025] Below the second belt conveyance unit 12, a maintenance unit 19 and a cap unit 30 (cap member) are arranged. The maintenance unit 19 horizontally moves below the recording unit 9 when performing a purge described later, wipes off the ink extruded from the discharge nozzles (see Figure 2) of the recording heads 17a - 17c described later, and collects the wiped-off ink. The cap unit 30 horizontally moves below the recording unit 9 when capping the ink ejection surface F (see Figure 4) of the recording heads 17a - 17c, and further moves upward to be attached to the lower surface of the recording heads 17a - 17c.

[0026] Figure 2 is a view of the first belt conveyance unit 5 and the recording unit 9 of the printer 100 as seen from above. Figure 3 is a view showing the structure of the recording unit 9 of the printer 100. Figure 4 is a view showing the structure of the recording heads 17a - 17c that constitute the line heads 11C - 11K of the recording unit 9 of the printer 100.

[0027] As shown in FIGS. 1 to 4, the recording unit 9 includes a head housing 10 and line heads 11C, 11M, 11Y, and 11K held by the head housing 10. The line heads 11C to 11K are supported at a height such that a predetermined interval (for example, 1 mm) is formed with respect to the conveyance surface of the first conveyance belt 8 stretched over a plurality of rollers including the drive roller 6 and the driven roller 7. Along the paper width direction (the vertical direction in FIG. 2), a plurality (here, three) of recording heads 17a to 17c are arranged in a staggered manner. The line heads 11C to 11K have a recording area larger than the width of the paper P to be conveyed, and discharge aqueous ink (hereinafter simply referred to as ink) from the discharge nozzles 18 corresponding to the printing positions onto the paper P conveyed by the first conveyance belt 8.

[0028] FIG. 5 is a view of the recording heads 17a to 17c of the printer 100 as seen from the ink discharge surface F side. As shown in FIG. 5, a nozzle area R is provided on the ink discharge surface F of the recording heads 17a to 17c. In the nozzle area R, a large number of openings at the tips of the discharge nozzles 18 (see FIG. 2) are arranged (not shown). Also, a water-repellent film (not shown) is formed on the ink discharge surface F. Since the recording heads 17a to 17c have the same shape and configuration, FIGS. 4 and 5 show the recording heads 17a to 17c in one figure.

[0029] For the recording heads 17a to 17c that make up each of the line heads 11C to 11K, inks of four colors (cyan, magenta, yellow, and black) stored in ink tanks (not shown) are supplied to each of the line heads 11C to 11K according to their colors.

[0030] Each of the recording heads 17a to 17c discharges ink from the discharge nozzles 18 (see FIG. 2) toward the paper P that is adsorbed and held on the conveyance surface of the first conveyance belt 8 and conveyed, according to the image data received from an external computer. Thereby, a color image in which inks of four colors, cyan, magenta, yellow, and black, are superimposed is formed on the paper P on the first conveyance belt 8.

[0031] To prevent ink ejection failure due to drying or clogging of the recording heads 17a to 17c, at the start of printing after a long-term stop, ink with a high viscosity in the nozzles is extruded from the ejection nozzles 18 (see Fig. 2) of all the recording heads 17a to 17c, and during the intervals between printing operations, from the ejection nozzles 18 of the recording heads 17a to 17c with an ink ejection amount below a specified value, and a purge is executed to prepare for the next printing operation.

[0032] Also, to prevent ink ejection failure due to drying or clogging of the recording heads 17a to 17c, a cap unit 30 can be attached to the recording heads 17a to 17c. The cap unit 30 is connected to a unit horizontal movement mechanism 65 (cap movement mechanism) and a unit lifting mechanism 66 (cap movement mechanism). The unit horizontal movement mechanism 65 and the unit lifting mechanism 66 move the cap unit 30 in the horizontal direction (here, the direction along the paper conveyance direction) and the vertical direction, so that the cap unit 30 can be moved between a first position where the cap portion 30b is separated from the ink ejection surface F of the recording heads 17a to 17c and a second position where it is attached to the ink ejection surface F.

[0033] Fig. 6 is a diagram showing the structure of the recording unit 9, the cap unit 30, the maintenance unit 19, etc. of the printer 100. Fig. 7 is a diagram showing the structure of the cap unit 30 of the printer 100. Figs. 8 and 9 are perspective views showing the structure of the carriage 71 of the printer 100. Fig. 8 shows a state where the support arm 74 is lying down, and Fig. 9 shows a state where the support arm 74 is standing up.

[0034] As shown in Figs. 6 and 7, the cap unit 30 includes a cap tray 30a, a cap portion 30b, and a height-direction positioning projection 30c. The cap tray 30a is a plate-shaped body made of sheet metal formed in a rectangular shape.

[0035] The cap portion 30b is disposed at a position on the upper surface of the cap tray 30a corresponding to the arrangement (staggered arrangement) of the recording heads 17a to 17c. The cap portion 30b is formed in a concave shape so that the ink ejection surface F enters the inside of the cap portion 30b when attached to the recording heads 17a to 17c. When the cap portion 30b is attached to the recording heads 17a to 17c, the ink ejection surface F abuts against the bottom surface of the cap portion 30b. Four height-direction positioning protrusions 30c are provided on the upper surface of the cap tray 30a.

[0036] The cap unit 30 can reciprocate between a facing position (the position in FIG. 12) directly below the recording unit 9 and facing the recording unit 9 in the vertical direction and a retracted position (the position in FIG. 6) retracted in the horizontal direction (arrow A direction) from the facing position by the unit horizontal movement mechanism 65. Further, the cap unit 30 can reciprocate between the above-described facing position (the first position) and a contact position (the second position) where the bottom surface of each cap portion 30b abuts against the ink ejection surface F of the recording heads 17a to 17c by the unit lifting mechanism 66. The cap portion 30b is attached in a state of abutting against the recording heads 17a to 17c and caps (seals) the recording heads 17a to 17c.

[0037] When the cap unit 30 is lifted toward the recording unit 9 to cap the recording heads 17a to 17c while the cap unit 30 is in the above-described facing position, the tip of the height-direction positioning protrusion 30c abuts against the head housing 10 of the recording unit 9 at a predetermined height. The contact between the height-direction positioning protrusion 30c and the head housing 10 restricts the upward movement of the cap unit 30 and keeps the contact state between the cap portion 30b and the ink ejection surface F constant.

[0038] As shown in FIG. 6, the unit horizontal movement mechanism 65 is provided below the recording unit 9. The unit horizontal movement mechanism 65 includes guide rails 60a and 60b, guide plates 61a and 61b, and a drive motor 72. The guide rails 60a and 60b are arranged along both ends in the paper width direction (arrow C-C' direction) of the recording unit 9 below the recording unit 9 so as to be parallel to the paper conveyance direction (arrow A direction). The guide plates 61a and 61b are fixed to the lower ends of the guide rails 60a and 60b. The side edge of the cap unit 30 is supported at the lower ends of the guide plates 61a and 61b.

[0039] A carriage 71 is slidably supported on the guide rails 60a and 60b in the paper conveyance direction. As shown in FIGS. 8 and 9, the carriage 71 is a box-shaped body composed of a bottom surface 77 and a pair of side wall portions 78. The pair of side wall portions 78 are formed to rise upward from both end edges of the bottom surface 77 with respect to the paper width direction. The pair of side wall portions 78 face each other in the paper width direction. The maintenance unit 19 is placed on the bottom surface 77 of the carriage 71 (see FIG. 6). Rack teeth 71a extending in the paper conveyance direction are formed at the upper ends of one side (here, the arrow C side) of the pair of side wall portions 78.

[0040] Returning to FIG. 6, the drive motor 72 is disposed outside the guide rail 60b (on the side of arrow C) with respect to the paper width direction. The drive motor 72 has a cover member 73 and a gear train (not shown). The cover member 73 is provided to cover the drive motor 72. The gear train is composed of an output shaft (not shown) of the drive motor 72 and a plurality of gears (not shown) engaged with the output shaft. The gear train is arranged to mesh with the rack teeth 71a. The gear train transmits the rotational driving force of the drive motor 72 to the carriage 71 via the rack teeth 71a. The rotational driving force of the drive motor 72 is transmitted to the carriage 71 as a driving force along the paper conveyance direction by the cam mechanism of the gear train and the rack teeth 71a. That is, when the drive motor 72 rotates forward, the gear train rotates, and the maintenance unit 19 together with the carriage 71 moves in one direction (here, the direction of arrow A´) of the paper conveyance direction. Conversely, when the drive motor 72 rotates reversely, the maintenance unit 19 together with the carriage 71 moves in the other direction (here, the direction of arrow A) of the paper conveyance direction.

[0041] The maintenance unit 19 (carriage 71) can reciprocate between a facing position (the position in FIG. 12, the first position) directly below the recording unit 9 and facing the recording unit 9 in the vertical direction and a retracted position (the position in FIG. 6) retracted in the horizontal direction (here, the paper conveyance direction) from the facing position. The maintenance unit 19 is configured to move upward at the facing position to perform a wiping operation (an operation of wiping off the ink discharged onto the ink ejection surface F).

[0042] The maintenance unit 19 (carriage 71) can reciprocate integrally with the cap unit 30 and can also reciprocate separately after being separated from the cap unit 30. The carriage 71 and the cap unit 30 can adopt a configuration in which an engagement mechanism (not shown) that engages when moving integrally with each other and separates when moving separately is provided.

[0043] As shown in FIGS. 8 and 9, the unit lifting mechanism 66 includes a support arm 74, a wiper lifting motor 76, a rotating shaft 75, and a guide groove 71b. The support arms 74 are provided at the four corners of the carriage 71. The support arms 74 support the maintenance unit 19 from the lower surface side and can swing (stand up or fall down). The support arms 74 adjacent to each other in the paper conveyance direction (the direction of arrow A - A') are connected via the rotating shaft 75. The support arm 74 swings between the standing state and the fallen state by the rotation of the rotating shaft 75.

[0044] The wiper lifting motor 76 is provided outside the carriage 71 (here, on the downstream side in the paper conveyance direction). The wiper lifting motor 76 has an output shaft and a gear train (not shown) composed of a plurality of gears. The gear train of the wiper lifting motor 76 engages with the rotating shaft 75 (not shown). When the output shaft of the wiper lifting motor 76 rotates forward, rotation is transmitted to the rotating shaft 75 via the gear train. When the rotating shaft 75 rotates forward from the state where the support arm 74 is fallen (the state in FIG. 8), the support arm 74 swings and assumes the standing state (the state shown in FIG. 9). Due to the raising and lowering of the support arm 74, the maintenance unit 19 moves up and down.

[0045] As shown in FIGS. 8 and 9, the guide groove 71b is formed on the inner surface (the inner surface in the paper width direction) of the other of the pair of side wall portions 78 of the carriage 71 (here, on the side of arrow C') so as to extend along the vertical direction. Guide protrusions (not shown) protruding toward the inside of the guide groove 71b are provided at both end portions of the maintenance unit 19 in the paper width direction. When the maintenance unit 19 moves up and down, the guide protrusions come into contact with the inner surface of the guide groove 71b, so that the movement in the paper conveyance direction is restricted while being guided in the vertical direction.

[0046] When attaching the cap unit 30 to the recording heads 17a to 17c, first, as indicated by the white arrow in FIG. 10, the first belt conveyance unit 5 is lowered. Then, as shown in FIG. 12, with the cap unit 30 placed on the maintenance unit 19, the maintenance unit 19 and the cap unit 30 are moved from the retracted position to the opposing position by the unit horizontal movement mechanism 65. After that, the maintenance unit 19 and the cap unit 30 are raised by the unit lifting mechanism 66, and the cap unit 30 (cap portion 30b) is attached to the recording heads 17a to 17c.

[0047] FIG. 13 is a block diagram showing an example of the control path of the printer 100 of the present embodiment. In addition to the above configuration, the printer 100 further includes a control device 110 (control unit), an operation panel 27 (input unit, display unit), a storage unit 28, and a communication unit 29.

[0048] The control device 110 is configured to include, for example, a CPU (Central Processing Unit) and a memory. Specifically, the control device 110 includes a main control unit 110a, a print completion time setting unit 110b, a paper supply control unit 110c, a maintenance control unit 110d, and a defect detection unit 110e.

[0049] The main control unit 110a controls the operations of each part of the printer 100. For example, the driving of each roller inside the printer 100, the ink ejection from the line heads 11C to 11K during image recording, etc. are controlled by the main control unit 110a. Further, the main control unit 110a has a count unit for counting time and a time setting unit for setting time (both not shown), and stores the settings of time and time in the storage unit 28. The main control unit 110a counts the ink ejection interval time from after ink ejection until the next ink ejection.

[0050] The printing completion time setting unit 110b sets the theoretical printing completion time at the start of printing. The theoretical printing completion time is calculated from the printing time based on the size information of the paper P and the number of printed sheets input from the operation panel 27 described later, calibration for density correction, flushing (empty ejection) to suppress ink ejection failures of the line heads 11C to 11K, maintenance time required for purging by the maintenance unit 19, etc., user response time required for replenishment of the paper P, switching of the paper feed stage, etc.

[0051] The paper supply control unit 110c controls the registration roller pair 13 and the paper feed devices 3a to 3b. For example, the paper supply control unit 110c controls the registration roller pair 13 based on the detection timing of the trailing edge of the paper P by the CIS 21, thereby controlling the conveyance timing of the subsequent paper P.

[0052] The maintenance control unit 110d performs control to execute the above-described purge that forcibly extrudes ink from the ink ejection nozzles 18 of the recording heads constituting each of the line heads 11C to 11K. Further, the maintenance control unit 110d also controls the driving of the unit horizontal movement mechanism 65 and the unit lifting mechanism 66 described above. When the above-described ink ejection interval time reaches a predetermined time (for example, one minute), the maintenance control unit 110d executes an operation of attaching the cap unit 30 to the recording heads 17a to 17c (hereinafter referred to as "cap operation"). The timing at which this ink ejection interval time reaches the predetermined time is referred to as the cap closing timing.

[0053] Here, for example, when paper jams occur around the recording unit 9 during printing, if the cap operation is executed in this state, the paper P will be sandwiched between the cap unit 30 and the recording heads 17a to 17c. Then, there is a risk that the recording heads 17a to 17c will be scratched or soiled, the cap unit 30 will be deformed, or the paper P will be torn, making it difficult to eliminate the paper jam. Therefore, when it is time for the cap to close, the maintenance control unit 110d will cancel the execution of the cap operation if it determines based on the detection result of the paper detection sensor 50 that the paper P is staying around the recording unit 9.

[0054] Also, when the main body cover 51 is in the open state, the unit horizontal movement mechanism 65 and the unit lifting mechanism 66 are cut off from the power supply. For this reason, when the main body cover 51 is in the open state, the maintenance control unit 110d will cancel the execution of the cap operation even when it is time to close.

[0055] The malfunction detection unit 110e can detect a movement inhibition factor from the states of each device and each sensor of the printer 100. The movement inhibition factor is a factor that inhibits the movement of the cap unit 30 to the second position. For example, the movement inhibition factors include paper jams of the paper P around the recording unit 9 described above, the main body cover 51 being in the open state, etc. In addition, it also includes cases where the cap operation cannot be executed due to some reason, cases where the user intentionally stops the execution of the cap operation, and cases where the main control unit 110a decides to postpone the execution of the cap operation based on the states of each device of the printer 100.

[0056] The operation panel 27 is an operation unit (input unit) for receiving various setting inputs. For example, the user can operate the operation panel 27 to input the size information of the paper P to be set in the paper feed cassettes 2a and 2b and the manual paper feed tray 2c. Further, the user can operate the operation panel 27 to input the number of sheets of the paper P to be printed and to instruct the start of a printing job. Further, the operation panel 27 also has a function as a notification device (display unit) for notifying the operation status of the printer 100.

[0057] The storage unit 28 is a memory that stores the operation program of the control device 110 and stores various types of information, and is configured to include a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile memory, and the like. The information set by the operation panel 27 is stored in the storage unit 28.

[0058] The storage unit 28 has a cap time storage unit 26 and a defect storage unit 24. The cap time storage unit 26 stores the cap closing time. The cap closing time is the cumulative time of the time during which the cap unit 30 is attached to the recording heads 17a to 17c. More specifically, it is the cumulative time of the time from when the cap unit 30 is attached to the recording heads 17a to 17c at the cap closing timing until the cap unit 30 is separated from the recording heads 17a to 17c for the next ink ejection.

[0059] The defect storage unit 24 stores information (hereinafter referred to as "defect information") regarding various defects that have occurred in the printer 100. The defect information includes the above-described movement inhibition factors, the occurrence times and occurrence frequencies of the movement inhibition factors, the cap movement impossible time described later, and the difference value between the cap closing and the cap movement impossible time.

[0060] The non-cap-movable time refers to the time from when the movement inhibition factor occurs at the cap closing timing to when the movement inhibition factor is eliminated. Examples of the non-cap-movable time are as follows. As described above, when the main body cover 51 is in the open state, the defect detection unit 110e detects the occurrence of the movement inhibition factor based on the detection result of the cover opening / closing detection sensor 53. When the main body cover 51 is in the closed state, the defect detection unit 110e detects the elimination of the movement inhibition factor based on the detection result of the cover opening / closing detection sensor 53. The time from the timing when the occurrence of the movement inhibition factor is detected (the timing when the opening of the main body cover 51 is detected) to the timing when the elimination of the movement inhibition factor is detected (the timing when the main body cover 51 is closed) is an example of the non-cap-movable time.

[0061] Also, as another example of the non-cap-movable time, when paper jamming occurs around the recording unit 9 during printing, the defect detection unit 110e detects the occurrence of the movement inhibition factor based on the detection result of the paper detection sensor 50. The time from the timing when the occurrence of the movement inhibition factor is detected (the timing when paper jamming of the paper P is detected) to the timing when the elimination of the movement inhibition factor is detected (the timing when the paper P is removed) is an example of the non-cap-movable time.

[0062] The main control unit 110a calculates a difference value obtained by subtracting the non-cap-movable time from the cap closing time. This difference value is stored in the defect memory unit 24 as defect information. This difference value means the time during which the cap unit 30 could not be attached due to the occurrence of the movement inhibition factor compared to the time when the cap unit 30 was originally attached to the recording heads 17a to 17c.

[0063] In addition, the main control unit 110a can execute the measurement mode. Instructions for starting and ending the measurement mode are directly input by the user from the operation panel 27. When a movement inhibition factor occurs during the execution of the measurement mode, the main control unit 110a stores defect information including this movement inhibition factor in the defect storage unit 24. When the end of the measurement mode is input from the operation panel 27, the defect information stored in the storage unit 28 is displayed on the operation panel 27.

[0064] The measurement mode can be started from the start point or a midpoint of the printing process, and can be ended at a midpoint or the end point of the printing process. Also, it is possible to set in advance to execute the measurement mode in a predetermined section. Details of the control example of the measurement mode will be described later.

[0065] The communication unit 29 is a communication interface for transmitting and receiving information to and from an external device (for example, a personal computer (PC)). For example, when the user operates the PC and transmits a print command together with image data to the printer 100, the above image data and print command are input to the printer 100 via the communication unit 29. In the printer 100, the main control unit 110a can control the recording heads 17a to 17c based on the above image data to eject ink, thereby recording an image on the paper P.

[0066] Next, the control example of the measurement mode described above will be explained using the flowchart shown in FIG. 14. FIG. 14 is a flowchart showing an example of the control flow of the measurement mode.

[0067] As shown in FIG. 14, the main control unit 110a determines whether an image formation command has been input from a host device such as a personal computer (step S1). If the image formation command is not input (No in step S1), the standby state for image formation is continued until the image formation command is input as it is.

[0068] When an image formation command is input (Yes in step S1), the main control unit 110a starts image formation and determines whether the execution of the measurement mode has been input (step S2). If the execution of the measurement mode has not been input (No in step S2), while continuing the image formation, the standby state of the measurement mode is continued until the execution of the measurement mode is input as it is.

[0069] When the execution of the measurement mode is input (Yes in step S2), the defect information stored in the defect storage unit 24 is deleted (step S3). Next, it is determined whether a movement inhibition factor has occurred during image formation (step S4). If a movement inhibition factor has occurred (Yes in step S4), the defect information regarding the movement inhibition factor (information including the movement inhibition factor, the time when the cap movement inhibition factor occurred, and the difference value between the cap closing time and the cap immovable time) is stored in the defect storage unit 24 (step S5). If no movement inhibition factor has occurred (No in step S4), step S5 is skipped and the process proceeds to step S6.

[0070] Next, it is determined whether the end of the measurement mode has been input (step S6). If the end of the measurement mode has been input (Yes in step S6), the defect information stored in the defect storage unit 24 is displayed on the operation panel 27 (step S7), and the control of the measurement mode is terminated. If the end of the measurement mode has not been input (No in step S6), the process returns to step S4, and steps S4 to S6 are repeated until the end of the measurement mode is input.

[0071] When repeatedly storing defect information between step S4 and step S6, for the cap movement impossible time and the above difference value, they are stored cumulatively in the already stored time. Specifically, after storing the cap movement impossible time in step S5, if the end of the measurement mode is not input (No in step S6) and another cap movement impossible time due to a different movement inhibiting factor is stored again in step S5, the main control unit 110a calculates the cumulative time obtained by adding the subsequently occurred cap movement impossible time to the previously stored cap movement time, and stores the cumulative time in the defect storage unit 24. Further, the main control unit 110a calculates the above difference value using the cumulative time of the cap movement impossible time as the cap movement impossible time, and stores it in the defect storage unit 24.

[0072] As described above, the printer 100 according to the above embodiment can detect the occurrence of a movement inhibiting factor and store the defect information in the defect storage unit 24. Then, the user can perform maintenance of the printer 100 based on the defect information stored in the defect storage unit 24, or review the operation method of the printer 100, the settings of the printing process, etc. Thereby, the occurrence of the movement inhibiting factor can be suppressed, and the execution frequency of the purge can be reduced. Therefore, a printer 100 capable of suppressing a decrease in productivity can be provided.

[0073] Here, when the printer 100 is used for so-called business use where thousands of prints are made in a single printing process, the user who operates the printer 100 is often a skilled person with rich knowledge about the printing process. When the user is a skilled person, there may be a case where the user wants to grasp the presence or absence of the occurrence of a movement inhibiting factor for the printing process during some time periods of a long printing process. In contrast, as described above, the printer 100 according to the above embodiment can execute and end the measurement mode by operating the operation panel 27. Therefore, the user can grasp the defect information regarding the movement inhibiting factor that occurred in an arbitrary section (time period).

[0074] Also, as described above, the defect information stored in the defect memory unit 24 includes the cap immovable time. By doing so, the user can grasp the time during which the movement inhibiting factor occurred. Also, as described above, the printer 100 according to the above embodiment stores the cap closing time in the memory unit 28, calculates the difference value between the cap closing time and the cap immovable time, and stores it in the defect memory unit 24 as defect information. By doing so, the user can grasp the time during which the cap unit 30 could not be attached due to the movement inhibiting factor with respect to the time during which the cap unit 30 was originally attached to the recording heads 17a to 17c. As a result, the user can perform maintenance of the printer 100, etc., assuming the drying condition of the ejection nozzles 18 and the timing of purging, and can suppress a decrease in productivity.

[0075] Also, as described above, the defect information includes the number of occurrences of the movement inhibiting factor. Therefore, the user can grasp the number of occurrences of the movement inhibiting factor and then perform suitable countermeasures (such as reviewing the operation method of the printer 100, the print settings, and the maintenance of the printer 100) to suppress the occurrence of the movement inhibiting factor. Also, as described above, the defect information includes the occurrence time of the movement inhibiting factor. Therefore, the timing of the occurrence of the movement inhibiting factor can be grasped.

[0076] Furthermore, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, the movement inhibiting factor may be stored in advance in the memory unit 28 described later, or may be configured such that the defect detection unit 110e or the main control unit 110a determines it from the operating state of the printer 100.

[0077] Also, although the cover open / close detection sensor 53 is assumed to employ an optical photosensor, for example, a mechanical button or switch capable of detecting the open / closed state of the main body cover 51 may be used.

[0078] Further, although the paper detection sensor 50 is configured to detect the presence or absence of the sheet P between the recording unit 9 and the first conveyance belt 8, it is also possible to adopt a configuration in which the CIS 21 detects the presence or absence of the sheet P between the recording unit 9 and the first conveyance belt 8 instead of the paper detection sensor 50.

[0079] The present invention is an image forming apparatus that forms an image on a recording medium by an inkjet recording method, and is applicable to an apparatus that attaches a cap to a recording head during an interval between printing processes. By using the present invention, when the frequency of purging or the amount of ink used for purging increases, a user can grasp information (defect information) about a factor (movement inhibition factor) that prevents the cap from being attached to the recording head. As a result, it becomes easier to suppress the occurrence of the movement inhibition factor, and an image forming apparatus capable of suppressing a decrease in productivity can be provided.

Claims

1. A conveyance unit that conveys a recording medium, A recording head having an ink ejection surface for ejecting ink, and performing a printing process by ejecting the ink from the ink ejection surface onto the recording medium conveyed by the conveyance unit, A cap member that is detachable from the ink ejection surface and protects the ink ejection surface, A cap movement mechanism that can move the cap member between a first position spaced apart from the ink ejection surface and a second position attached to the ink ejection surface, A control unit that controls the cap movement mechanism to move the cap member from the first position to the second position at a cap closing timing when a predetermined time has elapsed between the time when the ink is ejected from the ink ejection surface and the time when the ink is next ejected, In an inkjet recording apparatus comprising: A defect detection unit capable of detecting the occurrence of a movement inhibition factor that inhibits the movement of the cap member to the second position, A storage unit capable of storing defect information including the movement inhibition factor, Comprising: The control unit is capable of executing a measurement mode in which the defect information is stored in the storage unit based on the detection result of the defect detection unit, An input unit for inputting the execution and end of the measurement mode, A display unit for displaying the defect information, Comprising: When the execution of the measurement mode is input, the control unit deletes the defect information stored in the storage unit, stores the defect information generated during the subsequent printing process in the storage unit, and when the end of the measurement mode is input, displays the defect information stored in the storage unit. An inkjet recording apparatus characterized by this.

2. The conveyance unit is provided with a recording medium detection sensor capable of detecting whether the recording medium exists at a facing position where the recording medium faces the ink ejection surface, When the recording medium exists at the facing position at the cap closing timing, the defect detection unit detects the detection result of the recording medium detection sensor as the movement inhibition factor. The inkjet recording apparatus according to claim 1.

3. An apparatus main body in which the recording head and the cap movement mechanism are provided inside, An opening / closing cover provided on the apparatus main body for opening or closing the inside of the apparatus main body, A cover opening / closing detection sensor capable of detecting a state in which the opening / closing cover is open, Comprising: The malfunction detection unit according to claim 1 is characterized in that when the cover opening / closing detection sensor detects the open state of the opening / closing cover at the cap closing timing, the detection result of the cover opening / closing detection sensor is detected as the movement inhibition factor.

4. When the movement inhibition factor occurs at the cap closing timing, the control unit stores, in the storage unit, the time from the occurrence of the movement inhibition factor to the elimination of the movement inhibition factor as the cap movement impossible time. The malfunction information according to claim 1 is characterized in that it includes the cap movement impossible time.

5. The control unit stores, in the storage unit, the cap closing time from the cap closing timing to the timing of discharging the ink from the ink discharging surface thereafter, calculates a difference value between the cap closing time and the cap movement impossible time, and stores the difference value in the storage unit. The malfunction information according to claim 4 is characterized in that it includes the difference value.

6. The control unit stores the number of times the cap movement is impossible, which is the number of times the movement inhibition factor occurs at the cap closing timing. The malfunction information according to claim 1 is characterized in that it includes the number of times the cap movement is impossible.

7. The control unit stores, in the storage unit, the malfunction occurrence time, which is the occurrence time of the movement inhibition factor. The malfunction information according to claim 1 is characterized in that it includes the malfunction occurrence time.

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