JP6213433B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus.

  A general inkjet recording apparatus forms an image on a sheet by ejecting ink from a plurality of nozzles provided in a recording head. When the inkjet recording apparatus uses water-based ink, moisture permeates and the fibers swell on the first surface of the sheet where the image is formed. Accordingly, the area of the first surface of the sheet is expanded. As a result, the area of the first surface of the sheet may be larger than the area of the second surface of the sheet where no image is formed. Due to the difference between the area of the first surface of the sheet and the area of the second surface of the sheet, the first surface of the sheet curls in a convex shape.

  In view of this, the image forming apparatus described in Patent Document 1 causes the recording medium to wait until the recording medium is less likely to curl in a state where a part of the recording medium on which image formation by the recording head has been completed is restrained from above and below. . Specifically, the recording medium on which image formation has been completed is constrained by a plurality of conveying rollers for conveying the recording medium and a plurality of spur rollers arranged to face the plurality of conveying rollers. Thereafter, the recording medium is discharged.

JP 2006-082546 A

  However, in the image forming apparatus described in Patent Document 1, the end of the recording medium is not constrained. Therefore, in an image forming apparatus that forms an image on both sides of a sheet, the end portion of the sheet when re-conveyed immediately below the recording head may curl toward the recording head. As a result, the sheet may come into contact with the recording head. When the sheet contacts the recording head, the sheet may be contaminated or the edge of the sheet may be broken.

  The present invention has been made in view of the above problems, and an object thereof is to provide an ink jet recording apparatus capable of suppressing the sheet curled by the ink discharged onto the sheet from coming into contact with the recording head.

  According to the present invention, the ink jet recording apparatus forms an image on a sheet by the image forming unit. In the inkjet recording apparatus, a first conveyance path through which the sheet on which the image is formed is conveyed and a second conveyance path branched from the first conveyance path and re-conveyed to the image forming unit are formed. The The ink jet recording apparatus includes a storage unit that stores the sheet. The storage unit includes a storage unit and a correction unit. The storage unit stores the sheet. The correction unit curls the sheet. The storage unit is provided in the second transport path.

  According to the present invention, the sheet curled by the ink discharged onto the sheet can be prevented from coming into contact with the recording head.

It is sectional drawing which shows the inkjet recording device which concerns on embodiment of this invention. It is a figure which shows the storage part of the inkjet recording device which concerns on embodiment of this invention. It is a figure which shows operation | movement of the correction | amendment part of the inkjet recording device which concerns on embodiment of this invention. It is a figure which shows the guide plate of the inkjet recording device which concerns on embodiment of this invention. (A) It is sectional drawing which shows the guide plate of the inkjet recording device which concerns on embodiment of this invention. (B) It is sectional drawing which shows the inclined guide plate of the inkjet recording device which concerns on embodiment of this invention. It is a figure which shows the correction | amendment part of the inkjet recording device which concerns on embodiment of this invention from upper direction. (A) It is a figure which shows the feeding unit located in the standby position of the inkjet recording device which concerns on embodiment of this invention. (B) It is a figure which shows the feed unit located in the feed position of the inkjet recording device which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof is not repeated. In the present embodiment, the X axis and the Y axis are parallel to the horizontal plane, and the Z axis is parallel to the vertical line.

  With reference to FIG. 1, an ink jet recording apparatus 1 according to the present embodiment will be described. FIG. 1 shows an ink jet recording apparatus 1. In the ink jet recording apparatus 1, a first transport path 60 and a second transport path 70 are formed. The inkjet recording apparatus 1 includes a storage unit 10, a control unit 50, an image forming unit 80, a housing 100, a feeding unit 200, a transport unit 300, and a discharge tray 400. The ink jet recording apparatus 1 forms an image on the sheet S by the image forming unit 80. The sheet S is, for example, plain paper, recycled paper, thin paper, thick paper, or an OHP (Overhead Projector) sheet.

  The feeding unit 200 includes a feeding cassette 201 and a feeding roller 203. The feeding cassette 201 is detachably attached to the housing 100 and is disposed below the inside of the housing 100. A plurality of sheets S are stored in the feeding cassette 201. The feeding roller 203 is disposed above one end side of the feeding cassette 201. The feeding roller 203 feeds the sheet S stored in the feeding cassette 201 to the conveyance unit 300.

  The conveyance unit 300 is disposed on one side of the image forming unit 80. The conveyance unit 300 includes a registration roller pair 301. The conveyance unit 300 conveys the sheet S conveyed from the feeding cassette 201 to the image forming unit 80. The registration roller pair 301 is provided on the exit side of the transport unit 300. The registration roller pair 301 temporarily waits the sheet S, and then conveys the sheet S to the image forming unit 80 in accordance with the timing at which the image forming unit 80 forms an image on the sheet S.

  The image forming unit 80 forms an image on the sheet S. The image forming unit 80 is disposed above the feeding unit 200. The image forming unit 80 includes a transport mechanism 81 and a recording head 83. The transport mechanism 81 transports the sheet S transported from the transport unit 300 in the transport direction D toward the first transport path 60. The transport mechanism 81 includes an endless transport belt 810 and a suction unit 811. A plurality of through holes (not shown) penetrating the conveying belt 810 in the thickness direction are perforated. When the suction unit 811 is driven, a negative pressure is generated. The negative pressure acts on the sheet S supported on the conveyance surface of the conveyance belt 810 via the plurality of through holes of the conveyance belt 810. Accordingly, the sheet S is conveyed while being sucked by the suction unit 811 on the conveying belt 810.

  The recording head 83 forms an image by discharging aqueous ink onto the sheet S conveyed by the conveyance mechanism 81. The water-based ink contains, for example, a pigment or a dye as a coloring material. The image is formed on the first surface of the sheet S, or the first surface and the second surface of the sheet S. The first surface is a surface of the sheet S on which an image is formed during single-sided printing. The second surface is a surface facing the first surface of the sheet S. In the present embodiment, the recording head 83 has a plurality of heads corresponding to four colors arranged in parallel from the upstream side to the downstream side in the transport direction D. Each head includes a plurality of nozzles (not shown) arranged along the width direction (X-axis direction) of the transport mechanism 81. Ink is ejected onto the sheet S from a plurality of nozzles.

  The sheet S on which an image is formed is conveyed to the first conveyance path 60. The first transport path 60 is disposed downstream of the image forming unit 80 in the transport direction D of the sheet S. The first transport path 60 includes a transport roller pair 61. The sheet S conveyed on the first conveyance path 60 by the conveyance roller pair 61 is conveyed to the second conveyance path 70 when forming an image on the second surface of the sheet S, and forms an image on the second surface of the sheet S. If not, it is conveyed to the discharge tray 400. The discharge tray 400 is disposed outside the housing 100, and the sheet S is discharged to the discharge tray 400.

  In the second conveyance path 70, the sheet S is conveyed again to the image forming unit 80. The second conveyance path 70 is branched from the first conveyance path 60 and is disposed above the image forming unit 80. The storage unit 10 is provided in the second conveyance path 70. The sheet S conveyed through the second conveyance path 70 is re-conveyed to the image forming unit 80 by changing the conveyance direction in the storage unit 10. Accordingly, the second surface of the sheet S re-conveyed to the image forming unit 80 faces the recording head 83.

  The control unit 50 controls each element of the inkjet recording apparatus 1. Specifically, the control unit 50 executes a computer program stored in a storage device such as a main storage device (for example, a semiconductor memory) or an auxiliary storage device (for example, a hard disk drive). The image forming unit 80, the feeding unit 200, and the transport unit 300 are controlled. The control unit 50 is, for example, a CPU (Central Processing Unit).

  Next, the storage unit 10 will be described with reference to FIGS. FIG. 2 shows the storage unit 10. The storage unit 10 includes a storage unit 20, a correction unit 30, a retard roller 41, a feed roller 42, and three pressing units 90. The storage unit 10 stores the sheet S that is transported through the second transport path 70 and enters the storage unit 10. The sheet S entering the storage unit 10 has the first surface of the sheet S warped in a convex shape. Hereinafter, in this specification, the direction of curl that the first surface warps in a convex shape in a cross-sectional view from the width direction of the sheet S is referred to as a convex direction, and the first surface in a cross-sectional view from the width direction of the sheet S The direction of curl that warps in a concave shape is described as a concave direction. The width direction of the sheet S is a direction orthogonal to the conveyance direction of the sheet S.

  The storage unit 20 stores the sheet S. The storage unit 20 includes a stack guide 21 and a sheet front end guide 23. The stack guide 21 is substantially L-shaped in a side view. The sheet S entering the storage unit 10 is stacked on the stack guide 21. The surface on which the sheets S of the stack guide 21 are stacked is flat. In the present embodiment, a plurality of sheets S are stacked on the stack guide 21. A single sheet S may be stacked on the stack guide 21.

  The sheet front end guide 23 receives the front end of the sheet S entering the storage unit 10. The leading edge of the sheet S that enters the storage unit 10 may be the trailing edge of the sheet S that is re-conveyed to the image forming unit 80. The sheet front end guide 23 is attached so as to be movable along the stack guide 21 and is normally biased in a direction away from the lower end portion of the stack guide 21. The urging force with respect to the sheet leading end guide 23 is smaller than the resultant force of the moving force due to the weight of the sheet leading end guide 23 and the impact force when the sheet S comes into contact with the sheet leading end guide 23. Therefore, the sheet leading guide 23 moves toward the lower end of the stack guide 21 due to an impact when the sheet S comes into contact with the sheet leading guide 23. That is, the sheet front end guide 23 moves toward the lower end portion of the stack guide 21. The position of the sheet leading edge guide 23 is determined according to the number of sheets S and the weight of the sheet S. As a result, the tips of the plurality of sheets S stacked on the stack guide 21 are arranged. Note that the sheet leading end guide 23 can move to a position where it abuts against the lower end of the stack guide 21.

  The correction unit 30 enters the storage unit 10 and curls the rear end of the sheet S stored in the storage unit 20 in the concave direction. The trailing end of the sheet S entering the storage unit 10 may be the leading end of the sheet S that is re-conveyed to the image forming unit 80. The correction unit 30 includes a guide plate 31, a correction plate 32, a feeding unit 33, a guide shaft 34, and a correction shaft 323. On the guide plate 31, the rear end of the sheet S entering the storage unit 10 is stacked. The guide plate 31 rotates with the guide shaft 34 as a fulcrum. The correction plate 32 rotates with the correction shaft 323 as a fulcrum, and presses the sheet S toward the guide plate 31. The correction plate 32 functions as an entry guide for the sheet S, and the sheet S enters the storage unit 10 along the correction plate 32.

  The three pressing portions 90 press the sheets S stacked on the stack guide 21 toward the stack guide 21. Each of the three pressing portions 90 includes a pressing roller 91, a pressing shaft 92, and a pressing arm 93. The pressing roller 91 and the pressing shaft 92 are connected by a pressing arm 93. The pressing roller 91 rotates about the pressing shaft 92 as a fulcrum, and presses the sheets S stacked on the stack guide 21 toward the stack guide 21. Accordingly, the sheets S stacked on the stack guide 21 are pressed flat and curling in the convex direction of the sheets S is suppressed.

  In the present embodiment, two pressing portions 90 of the three pressing portions 90 rotate to suppress the sheet S. Based on the size of the conveyed sheet S, it may be determined whether or not the three pressing portions 90 are rotated, or the three pressing portions 90 may be rotated without being determined. A sensor may be provided in each of the three pressing portions 90 to determine whether or not the sheet S is positioned immediately below each of the three pressing portions 90 and rotate.

  FIG. 3 shows the operation of the correction unit 30. After the plurality of sheets S are stacked on the guide plate 31, the guide plate 31 rotates in the direction of the arrow R1, and the correction plate 32 tilts by rotating in the direction of the arrow R5, and sandwiches the rear end of the sheet S. . In the present embodiment, the arrow direction R1 and the arrow direction R5 are counterclockwise. Therefore, the rear end of the sheet S is curled in the concave direction. At this time, the first surface of the sheet S faces the guide plate 31, and the second surface of the sheet S faces the correction plate 32. Therefore, the rear end of the sheet S is curled in the concave direction. In the present embodiment, the state where the guide plate 31 and the correction plate 32 sandwich the rear end of the sheet S is maintained for 10 seconds. That is, the plurality of sheets S are curled in the concave direction for 10 seconds. The time for maintaining the state where the guide plate 31 and the correction plate 32 sandwich the sheet S is not limited to 10 seconds, and can be arbitrarily set.

  After curling the rear end of the sheet S in the concave direction, the guide plate 31 rotates in the direction of the arrow R2, and the correction plate 32 rotates in the direction of the arrow R6 to return to the state shown in FIG. In the present embodiment, the arrow direction R2 and the arrow direction R6 are clockwise. The feeding unit 33 feeds the sheet S curled in the concave direction between the retard roller 41 and the feed roller 42. The operation of the feeding unit 33 will be described later.

  The retard roller 41 and the feed roller 42 convey the sheet S fed to the feeding unit 33 toward the second conveyance path 70. The retard roller 41 and the feed roller 42 face each other. The feed roller 42 moves toward the retard roller 41, and the feed roller 42 and the retard roller 41 are pressed against each other. The retard roller 41 rotates following the feed roller 42 when one sheet S is fed. On the other hand, when a plurality of sheets S are overlapped and fed, the retard roller 41 rotates in the direction opposite to the conveyance direction of the sheet S, or the retard roller 41 stops and is in contact with the feed roller 42. The other sheet S is separated from the sheet S. As a result, one sheet S is conveyed by the feed roller 42.

  As described above with reference to FIGS. 1 to 3, according to the present embodiment, the storage unit 10 stores the sheet S in the storage unit 20 when storing the sheet S, and the correction unit 30 stores the sheet S. Curl in the concave direction. Accordingly, curling of the sheet S in the convex direction when re-conveyed to the image forming unit 80 is suppressed. As a result, the end of the sheet S is suppressed from contacting the recording head 83.

  According to the present embodiment, the correction unit 30 curls the rear end of the sheet S in the concave direction. Accordingly, the curling of the sheet S in the convex direction, that is, the curling of the end of the sheet S toward the recording head 83 when the sheet S is conveyed again to the image forming unit 80 can be suppressed. As a result, the contact of the sheet S with the recording head 83 is suppressed.

  Furthermore, according to the present embodiment, the sheet S curled in the convex direction is stored on the flat surface of the stack guide 21. Therefore, curling of the sheet S in the convex direction is suppressed. As a result, the sheet S is further suppressed from coming into contact with the recording head 83 when the sheet S is conveyed again to the image forming unit 80.

  Further, according to the present embodiment, the correction unit 30 curls a plurality of sheets S stacked on the stack guide 21 simultaneously in the concave direction. Therefore, compared with the case where the sheets S are curled one by one, the time for curling the sheets S per unit number in the concave direction can be extended while the time for curling the plurality of sheets S in the concave direction can be shortened. As a result, it is possible to shorten the time until a plurality of sheets S are fed from the feeding unit 200 and discharged to the discharge tray 400. That is, a decrease in productivity of the sheet S on which the image of the inkjet recording apparatus 1 is formed is suppressed.

  Further, according to the present embodiment, the sheet S is curled in the concave direction, that is, the leading edge of the sheet S that is re-conveyed to the image forming unit 80 is curled toward the conveyance mechanism 81. Accordingly, the suction unit 811 of the transport mechanism 81 can suck the sheet S with a small negative pressure. As a result, the driving force of the suction unit 811 can be reduced, and the load on the suction unit 811 can be reduced.

  The guide plate 31 will be described with reference to FIG. FIG. 4 is a view showing the guide plate 31. The guide plate 31 is plate-shaped. A pair of guide holes 312 are provided at both ends of the guide plate 31, and the guide shaft 34 is inserted therethrough. The guide shaft 34 is connected to the first motor 313. The controller 50 rotates the guide shaft 34 by controlling the driving force generated by the first motor 313.

  The operation of the guide plate 31 will be described with reference to FIGS. FIG. 5A shows the guide plate 31. FIG. 5B shows the inclined guide plate 31. The correction unit 30 further includes a torsion coil spring 35. A pressing portion 314 is projected from the end portion of the guide plate 31. The torsion coil spring 35 is disposed inside one of the pair of guide holes 312. The torsion coil spring 35 has a first end 351 and a second end 352. The first end 351 is provided at one end of the torsion coil spring 35, and the second end 352 is provided at the other end of the torsion coil spring 35. The guide shaft 34 is inserted through the torsion coil spring 35 and the pair of guide holes 312. Therefore, the torsion coil spring 35 rotates with the rotation of the guide shaft 34.

  The torsion coil spring 35 urges the guide plate 31 in the arrow direction R <b> 2 so that the guide plate 31 is substantially horizontal, and the pressing portion 314 of the guide plate 31 is pressed by the second end portion 352. The control unit 50 controls the first motor 313 to rotate the guide shaft 34 in the arrow direction R1. When the guide shaft 34 rotates in the arrow direction R1, the torsion coil spring 35 rotates around the guide shaft 34 in the arrow direction R1. As the torsion coil spring 35 rotates, the first end portion 351 presses the pressing portion 314 in the arrow direction R1. Accordingly, as the pressing portion 314 is pressed in the arrow direction R1, the guide plate 31 is tilted as shown in FIG. 5B by rotating in the arrow direction R1 around the guide shaft 34. . When the guide shaft 34 rotates in the arrow direction R2 by the first motor 313, the torsion coil spring 35 rotates in the arrow direction R2 around the guide shaft 34, and the second end 352 presses the pressing portion 314 in the arrow direction R2. . Therefore, the inclined guide plate 31 returns to the substantially horizontal again.

  The controller 50 changes the inclination of the guide plate 31 by controlling the driving force generated by the first motor 313. For example, the control unit 50 changes the inclination of the guide plate 31 based on the density of the image formed on the sheet S. Specifically, the higher the density of the image formed on the sheet S, the greater the amount of ink ejected onto the sheet S, so the curling of the sheet S in the convex direction by the ink increases. Therefore, the higher the density of the image formed on the sheet S, the more the correction unit 30 curls the sheet S in the concave direction. That is, the control unit 50 increases the inclination of the guide plate 31 as the density of the image formed on the sheet S is higher. When a plurality of sheets S are stacked on the stack guide 21, the control unit 50 may change the inclination of the guide plate 31 based on the highest density among the densities of images formed on the plurality of sheets S. Further, the control unit 50 may calculate the average value of the density of the images formed on the plurality of sheets S and change the inclination of the guide plate 31 based on the average value of the density. Further, the control unit 50 may set a first threshold value and change the inclination of the guide plate 31 based on the number of images formed with a density equal to or higher than the first threshold value.

  Further, the control unit 50 changes the inclination of the guide plate 31 based on the position of the image formed on the sheet S. Specifically, as the position of the image formed on the sheet S is closer to the front end of the sheet S when the sheet S is re-conveyed to the image forming unit 80, the front end of the sheet S curls in a convex direction. The sheet S is easy to contact the recording head 83. Accordingly, the closer the position of the image formed on the sheet S is to the front end of the sheet S when it is re-conveyed to the image forming unit 80, the more the correction unit 30 curls the front end of the sheet S in the concave direction. That is, as the position of the image formed on the sheet S is closer to the leading edge of the sheet S, the control unit 50 increases the inclination of the guide plate 31.

  When a plurality of sheets S are stacked on the stack guide 21, the control unit 50 guides the guide plate based on the position of the image formed closest to the front end of the sheet S among the images formed on the plurality of sheets S. The inclination of 31 may be changed. Further, the control unit 50 calculates the average value of the length from the position close to the leading edge of the sheet S of the image formed on the plurality of sheets S to the leading edge of the sheet S, and based on the average value of the length, the guide plate The inclination of 31 may be changed. In addition, the control unit 50 may set the second threshold value and change the inclination of the guide plate 31 based on the number of sheets S on which an image is formed at a position closer to the leading edge of the sheet S than the second threshold value. . Here, if the position of the image formed on the sheet S is not close to the front end of the sheet S that is re-conveyed to the image forming unit 80, the sheet S may not contact the recording head 83. Therefore, if the position of the image formed on the sheet S is not close to the front end of the sheet S, the correction unit 30 does not have to curl the sheet S in the concave direction.

  Further, the control unit 50 changes the inclination of the guide plate 31 based on the thickness of the sheet S. Specifically, the curling of the sheet S in the convex direction by the ink increases as the thickness of the sheet S decreases. Therefore, the control unit 50 increases the inclination of the guide plate 31 as the sheet S is thinner. When a plurality of sheets S are stacked on the stack guide 21, the inclination of the guide plate 31 may be changed based on the thinnest sheet S among the plurality of sheets S, or the average thickness of the plurality of sheets S may be changed. The inclination of the guide plate 31 may be changed by calculating a value.

  Further, the control unit 50 may change the inclination of the guide plate 31 based on at least one of the density and position of the image formed on the sheet S and the thickness of the sheet S described above. The inclination of the guide plate 31 may be changed based on the above combination. The configuration of the guide plate 31 described in the present embodiment is an example, and the configuration is not limited to the present embodiment as long as the configuration that can freely change the inclination of the guide plate 31 is satisfied.

  The correction plate 32 will be described with reference to FIGS. FIG. 6 shows the correction unit 30 from above. A feeding hole 321 is formed in the correction plate 32. A correction shaft 323 is attached to the base end of the correction plate 32, and the correction plate 32 is fixed to the correction shaft 323. Accordingly, the correction plate 32 rotates as the correction shaft 323 rotates. The correction plate 32 is normally biased in a direction away from the guide plate 31.

  The feeding unit 33 will be described with reference to FIGS. 1, 6, and 7. FIG. 7A shows the feeding unit 33 located at the standby position. The standby position is a position where the feeding unit 33 is retracted upward with respect to the correction plate 32. The feeding unit 33 includes a feeding shaft 331, a frame 332, and a pickup roller 334 attached to the frame 332. The feeding shaft 331 is fixed to the frame 332. Accordingly, the frame 332 rotates in the arrow direction R3 with the rotation of the feeding shaft 331, and the pickup roller 334 passes through the feeding hole 321 and descends to a position where it contacts the sheet S. In the present embodiment, the arrow direction R3 is counterclockwise. The pickup roller 334 is connected to the second motor 335 via the frame 332 and the feeding shaft 331. The driving force of the second motor 335 is transmitted to the pickup roller 334 via the feeding shaft 331 and the frame 332. The control unit 50 controls the driving force generated by the second motor 335 to rotate the feeding shaft 331 and rotate the pickup roller 334.

  A pair of contact portions 333 are formed on the frame 332. As the frame 332 rotates, the pair of contact portions 333 abut against the correction plate 32 and press the correction plate 32 downward. The urging force with respect to the correction plate 32 is smaller than the resultant force of the downward force due to the weight of the correction plate 32 and the pressing force when pressed against the frame 332. Therefore, when the frame 332 is pressed, the correction plate 32 descends against the urging force against the correction plate 32. As a result, the correction plate 32 rotates with the correction shaft 323 as a fulcrum and descends.

  FIG. 7B shows the feeding unit 33 located at the feeding position. When the sheet S feeding operation is started, the feeding unit 33 rotates from the standby position to the feeding position. The feeding position is a position where the pickup roller 334 contacts the sheet S. Specifically, the frame 332 rotates as the feeding shaft 331 rotates, and the pickup roller 334 contacts the sheet S. The sheet S is fed toward a position where the sheet S is nipped by the retard roller 41 and the feed roller 42 by the rotation of the pickup roller 334. When the feeding of the sheet S is completed, the control unit 50 rotates the feeding shaft 331 in the arrow direction R4, so that the feeding unit 33 returns to the standby position as shown in FIG. In the present embodiment, the arrow direction R4 is clockwise. While the feeding unit 33 returns to the standby position, the correction plate 32 also returns to the position shown in FIG.

  The embodiments of the present invention have been described above with reference to the drawings (FIGS. 1 to 7). However, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof (for example, (1) to (8) shown below). In order to facilitate understanding, the drawings schematically show each component as a main component, and the thickness, length, number, and the like of each component shown in the drawings are different from the actual for convenience of drawing. . Moreover, the shape, dimension, etc. of each component shown by said embodiment are an example, Comprising: It does not specifically limit, A various change is possible in the range which does not deviate substantially from the effect of this invention.

  (1) In this embodiment, when an image is not formed on the sheet S, the storage unit 10 does not have to curl the sheet S by the correction unit 30. As a result, the inkjet recording apparatus 1 can shorten the conveyance time of the sheet S.

  (2) As described with reference to FIGS. 2 and 3, the storage unit 10 includes the three pressing units 90. However, the storage unit 10 may include one pressing unit 90 or may include a plurality of pressing units 90 other than three.

  (3) As described with reference to FIGS. 2 and 3, the pressing portion 90 presses the sheet S by the pressing roller 91. However, the pressing unit 90 may be a fan, and may press the sheet S by blowing air.

  (4) As described with reference to FIG. 1, the recording head 83 has a plurality of heads corresponding to four colors. However, the recording head 83 may have a head corresponding to one color or a plurality of heads corresponding to a plurality of colors other than four colors.

  (5) As described with reference to FIGS. 1 to 3, the sheet S stored in the storage unit 10 is conveyed by the retard roller 41 and the feed roller 42 such that the plurality of sheets S overlap each other. Suppressed. However, instead of the retard roller 41, the separation pad and the feed roller 42 may prevent the plurality of sheets S from being overlapped and conveyed.

  (6) As described with reference to FIG. 4, the sheets S are stacked on the guide plate 31. A pair of cursors may be provided at both ends along the width direction of the guide plate 31. The pair of cursors sandwich the sheet S stacked on the guide plate 31 and suppress the conveyance of the sheet S in an oblique posture.

  (7) As described with reference to FIG. 6, the correction plate 32 is biased, and the correction plate 32 rotates with the rotation of the frame 332. However, the correction shaft 323 may be connected to a motor and rotated by the driving force of the motor, and the correction plate 32 may rotate as the correction shaft 323 rotates.

  (8) As described with reference to FIGS. 4 to 7, the guide shaft 34 is connected to the first motor 313, and the feeding shaft 331 is connected to the second motor 335. However, the guide shaft 34 and the feed shaft 331 may be connected to the first motor 313, or the guide shaft 34 and the feed shaft 331 may be connected to the second motor 335.

  The present invention can be used in the field of inkjet recording apparatuses.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 10 Storage part 20 Storage part 30 Correction part 31 Guide plate 32 Correction plate 50 Control part 60 1st conveyance path 70 2nd conveyance path 80 Image formation part 90 Pressing part S Sheet

Claims (5)

An inkjet recording apparatus that forms an image on a sheet by an image forming unit,
A first conveyance path for conveying the sheet on which the image is formed, and a second conveyance path for branching from the first conveyance path and re-conveying the sheet to the image forming unit;
A storage unit for storing the sheet ;
A control unit ,
The storage unit is
A storage section for storing the sheet;
A correction part for curling the sheet, and
The storage unit is provided in the second transport path,
The correction part is
A guide plate on which the sheets are stacked;
A correction plate for pressing the sheet toward the guide plate;
Have
The said control part is an inkjet recording device which changes the inclination of the said guide plate .
Before SL control unit, based on the density of the image formed on the sheet, changing the inclination of the guide plate, the ink jet recording apparatus according to claim 1.
Wherein, based on the position of the image formed on the sheet, changing the inclination of the guide plate, the ink jet recording apparatus according to claim 1 or claim 2.
Wherein, based on the thickness of the sheet, changing the inclination of the guide plate, the ink jet recording apparatus according to any one of claims 1 to 3.
Said storage unit, said towards the reservoir further comprising a pressing portion for pressing the sheet, the ink jet recording apparatus according to any one of claims 1 to 4.