JP2014031280A - Sheet curl correction device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet curl correction device in which a curl correction unit can be miniaturized.SOLUTION: A curl correction device includes: a supporting member 512 for supporting a first roller 85a and a second roller 85b; a first driving source 540 for rotating the supporting member 512; a first gear 552 connected to an end, on the side of the first driving source 540, of the second roller 85b; a relay gear 553 that engages with the first gear 552; an input gear 515 that engages with the relay gear 553 and rotates around a third rotation shaft 511; a second driving source 530 for transmitting a torque to the input gear 515; and an outer circumferential gear 514 that rotates around the third rotation shaft 511 and has a peripheral surface having gear teeth formed therein. The third rotation shaft 511 extends parallel to an axial direction of a first rotation shaft 551 on a surface including the first rotation shaft 551 and a second rotation shaft 561, the outer circumferential gear 514 is connected to the supporting member 512 to be relatively unrotatable, and the first driving source 540 rotates the supporting member 512 by 180° around the third rotation shaft 511.

Description

  The present invention includes, for example, a sheet curl correcting apparatus that corrects curl generated in a sheet such as a sheet on which an image is formed in an image forming apparatus such as a copier, a printer, and a facsimile, and the sheet curl correcting apparatus. The present invention relates to an image forming apparatus.

  In an image forming apparatus such as a copying machine, a toner image is formed on a sheet such as a paper sheet in an image forming unit including a photosensitive drum, and then the toner image is fixed on the sheet by applying heat and pressure in a fixing unit. Therefore, the sheet that has passed through the fixing unit is likely to curl. For example, when a sheet with such curling is discharged to the discharge tray as it is, when a plurality of sheets are stacked on the discharge tray, a gap is generated between the sheets due to the curl, and the accommodation property is deteriorated. Problems with the handling of the sheet, such as irregular sheets.

In view of this, a sheet curl correction apparatus has been put to practical use in which a sheet is passed between a pair of curl correction rollers to correct the sheet curl.
Incidentally, the curl generated in the sheet includes “upper curl” in which the leading edge of the sheet is bent toward the upper surface of the sheet and “lower curl” in which the leading edge of the sheet is bent toward the lower surface of the sheet. Therefore, a curl correction device that can correct both the upper curl and the lower curl is desired.

  In order to meet this demand, the curl correction direction by the curl correction roller pair is changed by rotating the curl correction unit having a support member that rotatably supports the curl correction roller pair to change the arrangement of the curl correction roller pair. There has been proposed a curl correction device that can change the above (for example, see Patent Documents 1 and 2).

  In addition, a curl correction unit having a support member that rotatably supports three curl correction rollers, and a curl direction (upward) of the sheet that is arranged and conveyed upstream of the curl correction unit in the sheet conveyance direction. Curl detection means for detecting curl or lower curl), and the curl correction direction by the three curl correction rollers can be changed by controlling the rotation of the curl correction unit based on the detection of the curl by the curl detection means A curl correction device has also been proposed (see, for example, Patent Document 3).

JP 2009-29554 A Japanese Patent Laid-Open No. 10-231061 JP 2004-26419 A

However, further downsizing is desired in the curl correction apparatus.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sheet curl correction apparatus that can reduce the size of a curl correction unit.
Another object of the present invention is to provide an image forming apparatus including the sheet curl correcting apparatus.

The present invention is a sheet curl correction device that corrects a sheet curl by passing the sheet between a first roller and a second roller, and rotates around a first rotation axis and is elastically deformable. A first roller formed on the first rotation shaft, a second roller that rotates about a second rotation shaft parallel to the axial direction of the first rotation shaft, and is formed to be harder than the first roller, and the first roller A roller and a support member for supporting the second roller; a first drive source for rotating the support member around a third rotation axis; and an end of the second roller on the first drive source side. A first gear, a second gear meshing with the first gear, a third gear rotating coaxially with the second gear, and an input gear meshing with the third gear;
A second drive source for transmitting a rotational force to the input gear, wherein the second roller forms a curved nip portion through which the sheet passes with the first roller. The third rotating shaft extends in parallel with the axial direction of the first rotating shaft within a first surface including a start edge and a terminal edge of the nip portion, and is pressed against the first roller. The driving source has a first position for receiving the sheet toward the nip portion from the starting edge side of the nip portion, and a second position for receiving the sheet toward the nip portion from the terminal edge side of the nip portion. It is related with the curl correction apparatus of the sheet | seat rotated between.

  In addition, the outer gear further includes an outer peripheral gear rotatably supporting the input gear and having a peripheral surface formed with gear teeth, the outer peripheral gear being connected to the support member so as not to rotate relative to the support member. One drive source is preferably connected to the outer peripheral gear.

  The third rotation shaft is preferably formed along an intersection line between the first surface and the second surface including the first rotation shaft and the second rotation shaft.

  The present invention also provides an image forming unit that forms an image on a sheet, a fixing unit that fixes the image to the sheet using heat, and a curl of the sheet that corrects curling of the sheet on which the image is fixed. The sheet curl correcting apparatus, wherein the sheet curl correcting apparatus rotates around a first rotation axis and is elastically deformable, and a first roller parallel to the axial direction of the first rotation axis. A second roller that rotates about the two rotation shafts and is harder than the first roller; a support member that supports the first roller and the second roller; and Together with a first drive source that rotates around the first gear, a first gear connected to an end of the second roller on the first drive source side, a second gear meshing with the first gear, and the second gear A third gear that rotates coaxially and meshes with the third gear An input gear and a second drive source that transmits a rotational force to the input gear, and the second roller forms a curved nip portion through which the sheet passes with the first roller. The third rotating shaft extends in parallel with the axial direction of the first rotating shaft within a first surface including a start edge and a terminal edge of the nip portion. The first driving source is configured to receive the support member from the starting edge side of the nip portion from the starting edge side of the nip portion, and from the terminal edge side of the nip portion to the nip portion. The present invention relates to an image forming apparatus that is rotated between a receiving second position and the second position.

  The present invention also relates to a sheet curl correction device for correcting sheet curl by passing the sheet between a first roller and a second roller, the first roller and the second roller, A third rotation that supports the first roller and the second roller in a rotatable manner, and is parallel to a first rotation shaft that is a rotation shaft of the first roller and a second rotation shaft that is a rotation shaft of the second roller. A curl correction unit that can change a curl correction direction by the first roller and the second roller by rotating the support member, and a support member that rotates around the shaft. A first drive source that rotationally drives, a second drive source that rotationally drives one or both of the first roller and the second roller, and the first drive source and the second drive source, The curl correction unit One end side of the first rotation shaft of the first roller and the second rotation shaft of the second roller in the curl correction unit is provided on a fixing member on the apparatus main body side that is rotatably supported. The first drive source and the second drive source are related to a sheet curl correction apparatus including a single drive motor that can switch a rotation direction to a normal rotation direction or a reverse rotation direction.

  The first roller is formed so as to be elastically deformable, and the second roller rotates around the second rotation axis parallel to the axial direction of the first rotation shaft, and more than the first roller. A first gear that is rigidly connected to the end of the second roller on the first drive source side, a second gear that meshes with the first gear, and a third gear that rotates coaxially with the second gear. And an input gear that meshes with the third gear, and a second drive source that transmits rotational force to the input gear, and the sheet passes between the second roller and the first roller. It is preferable to press the first roller so as to form a curved nip portion.

  The curl correction device further includes an outer peripheral gear that is non-rotatably connected to the support member, and the curl correction unit includes the input gear fixed to the third rotation shaft. The first drive source rotationally drives the support member via the outer peripheral gear, and the second drive source is one or both of the first roller and the second roller via the input gear. Is preferably driven to rotate.

  The third rotating shaft extends in parallel with an axial direction of the first rotating shaft within a first surface including a start edge and a terminal edge of the nip portion, and the first drive source is the support member. Between the first position for receiving the sheet toward the nip portion from the start edge side of the nip portion and the second position for receiving the sheet toward the nip portion from the end edge side of the nip portion. It is preferable.

  The curl correction unit includes a sheet introduction guide path that guides introduction of a sheet into a nip portion between the first roller and the second roller, and a gap between the first roller and the second roller. A sheet lead-out guide path that guides the lead-out of the sheet from the nip portion, and the sheet introduction guide path and the sheet lead-out guide path rotate with the rotation of the support member of the curl correction unit. It is preferable to be configured.

  The present invention also relates to an image forming apparatus comprising: an image forming unit that forms an image on a sheet; and the curl correcting device for the sheet that corrects curl of the sheet on which an image is formed by the image forming unit.

ADVANTAGE OF THE INVENTION According to this invention, the curl correction apparatus of the sheet | seat which can achieve size reduction of a curl correction unit can be provided.
Further, according to the present invention, it is possible to provide an image forming apparatus including the sheet curl correcting apparatus.

FIG. 3 is a diagram for explaining an arrangement of each component of the copier 1 according to the first embodiment of the present invention. FIG. 3 is a perspective view illustrating a configuration of a curl correction unit 510 of a paper curl correction apparatus 500 in the copier 1 according to the first embodiment. FIG. 3 is a perspective view showing a configuration of a curl correction unit 510 in a state reversed 180 ° with respect to FIG. 2. It is a perspective view which shows the structure of the curl correction unit 510 from the hard roller 85b side. 4 is an enlarged vertical sectional view of a main part showing the configuration of a curl correction unit 510. FIG. FIG. 6 is an enlarged longitudinal sectional view showing a start edge 85d and a terminal edge 85e of a nip portion 85c in the curl correction unit 510. 5 is an enlarged perspective view of a main part showing the configuration of a fixing member 520 on the apparatus main body side of the curl correction apparatus 500. FIG. FIG. 5 is a perspective view showing a state in which the curl correction unit 510 is assembled to the fixing member 520 on the apparatus main body side. FIG. 6 is an enlarged perspective view of a main part showing a configuration of a unit drive motor 540 that rotationally drives a curl correction unit 510. 5 is an enlarged perspective view of a main part showing a configuration of a roller drive motor 530 of the curl correction apparatus 500. FIG. FIG. 6 is an enlarged longitudinal sectional view of a main part for explaining a state in which a curl correction unit 510 is rotated so that a curl correction direction by a curl correction roller pair 85 is a first direction. FIG. 5 is an enlarged longitudinal sectional view of a main part for explaining a state in which a curl correction unit 510 is rotated so that a curl correction direction by a curl correction roller pair 85 is a second direction. FIG. 6 is an enlarged perspective view of a main part showing a configuration of a single drive motor 600 that rotates and drives a curl correction unit 510 of a paper curl correction apparatus 500A in a copier 1 according to a second embodiment of the present invention, and its periphery. FIG. 10 is an enlarged plan view of a main part showing a configuration of a single drive motor 600 for rotating and driving a curl correction unit 510 of a paper curl correction apparatus 500A in a copier 1 of a second embodiment, and its periphery.

<First Embodiment>
Hereinafter, a first embodiment of an image forming apparatus of the present invention will be described with reference to the drawings.
With reference to FIG. 1, the overall structure of a copier 1 as an image forming apparatus in the first embodiment will be described. FIG. 1 is a diagram for explaining the arrangement of components of the copier 1 according to the first embodiment.

As shown in FIG. 1, a copying machine 1 as an image forming apparatus includes an image reading device 300 disposed on the upper side in the vertical direction Z of the copying machine 1 and an apparatus body M. The apparatus main body M is disposed below the vertical direction Z in the copying machine 1 and forms a toner image on a sheet T as a sheet (transfer material) based on image information read by the image reading apparatus 300.
In the description of the copying machine 1, the sub-scanning direction X of the image reading device 300 is also referred to as the “left-right direction” of the copying machine 1, and the main scanning direction Y of the image reading device 300 (direction passing through FIG. 1, see FIG. 2). Is also referred to as “front-rear direction” of the copy machine 1. The vertical direction Z of the copier 1 is orthogonal to the sub-scanning direction X and the main scanning direction Y.

First, the image reading apparatus 300 will be described.
As shown in FIG. 1, the image reading apparatus 300 includes a reading unit 301 that reads an image of a document G, and a document conveying unit 70 that is arranged above the reading unit 301 and conveys the document G to the reading unit 301. .
The reading unit 301 includes a first reading surface 302A and a second reading surface 302B on the upper side. The document G from the document transport unit 70 is transported on the first reading surface 302A. A document G is placed on the second reading surface 302B by the user.

  The document conveyance unit 70 is connected to the reading unit 301 so as to be opened and closed by a connection unit (not shown). The document transport unit 70 has a document placement unit 71 on the upper side, and a feed roller (not shown) inside the document transport unit 70. The document conveyance unit 70 has a function of covering the first reading surface 302A and the second reading surface 302B of the reading unit 301.

  The first reading surface 302 </ b> A is a reading surface used when reading the document G conveyed by the document conveying unit 70. The first reading surface 302A is formed along the upper surface of the first contact glass 335A. The first reading surface 302A is located in the vicinity of the left side surface of the reading unit 301.

The second reading surface 302 </ b> B is a reading surface used when reading the document G without using the document transport unit 70. The second reading surface 302B is formed along the upper surface of the second contact glass 335B. The second reading surface 302B is on the right side of the first reading surface 302A and extends over most of the sub-scanning direction X in the reading unit 301.
The first reading surface 302A and the second reading surface 302B extend in the sub-scanning direction X and the main scanning direction Y.

  When reading the document G conveyed by the document conveyance unit 70, the document G is placed on the document placement unit 71. The document G placed on the document placement unit 71 is conveyed to the first reading surface 302 </ b> A of the reading unit 301 by the feed roller provided inside the document conveying unit 70. The original G is conveyed onto the first reading surface 302A by the original conveying unit 70, whereby the image formed on the surface of the original G is read by the reading unit 301.

  In addition, the document G is placed on the second reading surface 302B by the user when the document transport unit 70 is in the open state. The image of the original G placed on the second reading surface 302B is read by the reading unit 301.

Next, the apparatus main body M will be described.
The main body M of the apparatus forms an image forming unit GK that forms a predetermined toner image on the paper T based on predetermined image information, and feeds the paper T to the image forming unit GK and discharges the paper T on which the toner image is formed. A paper supply / discharge section KH for paper.
The outer shape of the apparatus main body M is configured by a case body BD as a casing.

  As shown in FIG. 1, the image forming unit GK includes photosensitive drums 2a, 2b, 2c, and 2d as image carriers (photosensitive members), charging units 10a, 10b, 10c, and 10d, and a laser as an exposure unit. Scanner units 4a, 4b, 4c, 4d, developing devices 16a, 16b, 16c, 16d, toner cartridges 5a, 5b, 5c, 5d, toner supply units 6a, 6b, 6c, 6d, drum cleaning unit 11a, 11b, 11c, 11d, static eliminators 12a, 12b, 12c, 12d, intermediate transfer belt 7, primary transfer rollers 37a, 37b, 37c, 37d, secondary transfer roller 8, counter roller 18, fixing Part 9.

  As shown in FIG. 1, the paper feed / discharge unit KH includes a paper feed cassette 52, a manual paper feed unit 64, a conveyance path L for paper T, a pair of registration rollers 80, and a curl correction device 500 (described later). A pair of curl correction rollers 85, a first paper discharge unit 50a, and a job separator 400 including a second paper discharge unit 50b. As will be described later, the transport path L includes the first transport path L1, the second transport path L2, the third transport path L3, the fourth transport path L4, the manual transport path La, and the return transport path Lb. , A reverse conveyance path Lc, a sub conveyance path Ld, and a merging conveyance path Le.

Hereinafter, each configuration of the image forming unit GK and the paper supply / discharge unit KH will be described in detail.
First, the image forming unit GK will be described.
In the image forming unit GK, charging by the charging units 10a, 10b, 10c, and 10d in order from the upstream side to the downstream side in order along the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d, the laser scanner unit 4a, 4b, 4c, 4d exposure, development devices 16a, 16b, 16c, 16d development, intermediate transfer belt 7 and primary transfer rollers 37a, 37b, 37c, 37d primary transfer, static eliminators 12a, 12b, 12c, 12d Is eliminated, and cleaning is performed by the drum cleaning units 11a, 11b, 11c, and 11d.
Further, in the image forming unit GK, secondary transfer by the intermediate transfer belt 7, the secondary transfer roller 8 and the counter roller 18, and fixing by the fixing unit 9 are performed.

  Each of the photosensitive drums 2a, 2b, 2c, and 2d is formed of a cylindrical member and functions as a photosensitive member or an image carrier. Each of the photosensitive drums 2 a, 2 b, 2 c, and 2 d is disposed so as to be rotatable in the direction of an arrow about an axis that extends in a direction orthogonal to the traveling direction of the intermediate transfer belt 7. An electrostatic latent image can be formed on the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d.

  Each of the charging units 10a, 10b, 10c, and 10d is disposed to face the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the charging units 10a, 10b, 10c, and 10d uniformly charges the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d negatively (minus polarity) or positively (plus polarity).

  The laser scanner units 4a, 4b, 4c, and 4d function as exposure units, and are spaced apart from the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the laser scanner units 4a, 4b, 4c, and 4d includes a laser light source (not shown), a polygon mirror, a polygon mirror driving motor, and the like.

  Each of the laser scanner units 4a, 4b, 4c, and 4d scans and exposes the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d based on image information related to the image read by the reading unit 301. The scanning exposure is performed by each of the laser scanner units 4a, 4b, 4c, and 4d, thereby removing the charges on the exposed portions of the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d. Thereby, electrostatic latent images are formed on the respective surfaces of the photosensitive drums 2a, 2b, 2c, and 2d.

  The developing devices 16a, 16b, 16c, and 16d are provided corresponding to the photosensitive drums 2a, 2b, 2c, and 2d, respectively, and are disposed to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the developing devices 16a, 16b, 16c, and 16d attaches the toner of each color to the electrostatic latent image formed on the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d, and converts the color toner image into the photosensitive drum. 2a, 2b, 2c and 2d are formed on the respective surfaces. Each of the developing devices 16a, 16b, 16c, and 16d corresponds to four colors of yellow, cyan, magenta, and black. Each of the developing devices 16a, 16b, 16c, and 16d includes a developing roller disposed opposite to the surface of the photosensitive drums 2a, 2b, 2c, and 2d, a stirring roller for stirring the toner, and the like.

  Each of the toner cartridges 5a, 5b, 5c, and 5d is provided corresponding to each of the developing devices 16a, 16b, 16c, and 16d, and each color toner supplied to each of the developing devices 16a, 16b, 16c, and 16d. To accommodate. Each of the toner cartridges 5a, 5b, 5c, and 5d accommodates yellow toner, cyan toner, magenta toner, and black toner.

  The toner supply units 6a, 6b, 6c, and 6d are provided corresponding to the toner cartridges 5a, 5b, 5c, and 5d and the developing devices 16a, 16b, 16c, and 16d, respectively. The toners of the respective colors accommodated in 5d are supplied to the developing devices 16a, 16b, 16c, and 16d, respectively. Each of the toner supply units 6a, 6b, 6c, and 6d and each of the developing devices 16a, 16b, 16c, and 16d are connected by a toner supply path (not shown).

  To the intermediate transfer belt 7, the toner images of the respective colors formed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially primary-transferred. The intermediate transfer belt 7 is stretched around a driven roller 35, a counter roller 18 including a driving roller, a tension roller 36, and the like. Since the tension roller 36 biases the intermediate transfer belt 7 from the inside to the outside, a predetermined tension is applied to the intermediate transfer belt 7.

  Primary transfer rollers 37a, 37b, 37c, and 37d are arranged to face each other on the side opposite to the photosensitive drums 2a, 2b, 2c, and 2d with the intermediate transfer belt 7 interposed therebetween.

  A predetermined portion of the intermediate transfer belt 7 is sandwiched between the primary transfer rollers 37a, 37b, 37c, and 37d and the photosensitive drums 2a, 2b, 2c, and 2d, respectively. The predetermined portion thus sandwiched is pressed against the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d. Primary transfer nips N1a, N1b, N1c, and N1d are formed between the photosensitive drums 2a, 2b, 2c, and 2d and the primary transfer rollers 37a, 37b, 37c, and 37d, respectively. In each of the primary transfer nips N1a, N1b, N1c, and N1d, the toner images of the respective colors developed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially primary-transferred onto the intermediate transfer belt 7, respectively. As a result, a full-color toner image is formed on the intermediate transfer belt 7.

  To the primary transfer rollers 37a, 37b, 37c, and 37d, toner images of the respective colors formed on the photosensitive drums 2a, 2b, 2c, and 2d are respectively transferred to the intermediate transfer belt 7 by a primary transfer bias applying unit (not shown). A primary transfer bias for transferring the toner image is applied.

  The static eliminators 12a, 12b, 12c, and 12d are arranged to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, respectively. The static eliminators 12a, 12b, 12c, and 12d respectively irradiate the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d to irradiate light, and the photosensitive drums 2a, 2b, and 2c after the primary transfer is performed. 2d, each surface is neutralized (charge is removed).

  The drum cleaning units 11a, 11b, 11c, and 11d are disposed to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, respectively. Each of the drum cleaning units 11a, 11b, 11c, and 11d removes toner and adhering matter remaining on the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, and conveys the removed toner to a predetermined recovery mechanism. And collect it.

  The secondary transfer roller 8 secondarily transfers the full-color toner image primarily transferred to the intermediate transfer belt 7 onto the paper T. A secondary transfer bias for transferring the full color toner image formed on the intermediate transfer belt 7 to the paper T is applied to the secondary transfer roller 8 by a secondary transfer bias applying unit (not shown).

  The secondary transfer roller 8 contacts or separates from the intermediate transfer belt 7. Specifically, the secondary transfer roller 8 is configured to be movable between a contact position where the secondary transfer roller 8 is in contact with the intermediate transfer belt 7 and a spaced position where the secondary transfer roller 8 is separated from the intermediate transfer belt 7. Specifically, the secondary transfer roller 8 is disposed at a contact position when the full-color toner image primarily transferred onto the surface of the intermediate transfer belt 7 is secondarily transferred to the paper T, and in other cases. It is arranged at a separated position.

  A counter roller 18 is disposed on the opposite side of the intermediate transfer belt 7 from the secondary transfer roller 8. A predetermined portion of the intermediate transfer belt 7 is sandwiched between the secondary transfer roller 8 and the opposing roller 18. Then, the paper T is pressed against the outer surface of the intermediate transfer belt 7 (the surface on which the toner image is primarily transferred). A secondary transfer nip N <b> 2 is formed between the intermediate transfer belt 7 and the secondary transfer roller 8. In the secondary transfer nip N2, the full-color toner image primarily transferred to the intermediate transfer belt 7 is secondarily transferred to the paper T.

  The fixing unit 9 melts and presses the toner of each color constituting the toner image secondarily transferred onto the paper T and fixes the toner on the paper T. The fixing unit 9 includes a heating rotator 9a heated by a heater and a pressure rotator 9b pressed against the heating rotator 9a. The heating rotator 9a and the pressure rotator 9b sandwich and pressurize the paper T onto which the toner image has been secondarily transferred, and convey the paper T. By transporting the paper T while being sandwiched between the heating rotator 9a and the pressure rotator 9b, the toner transferred to the paper T is fixed to the paper T by being melted and pressurized. The

Next, the paper supply / discharge unit KH will be described.
As shown in FIG. 1, the paper feed cassette 52 is a cassette that accommodates paper T, and two cassettes are arranged below the apparatus main body M in the vertical direction. The paper feed cassette 52 is configured to be pulled out from the housing of the apparatus main body M in the horizontal direction. In the paper feed cassette 52, a placement plate 60 on which the paper T is placed is disposed. In the paper feed cassette 52, the paper T is stored in a state of being stacked on the placement plate 60. The paper T placed on the placement plate 60 is sent out to the transport path L by the cassette paper feed unit 51 arranged at the paper feed side end of the paper feed cassette 52 (the right end in FIG. 1). . The cassette paper feed unit 51 includes a forward feed roller 61 for taking out the paper T on the placement plate 60 and a paper feed roller pair 63 for feeding the paper T one by one to the transport path L. Is provided.

  The manual paper feed unit 64 is provided on the right side surface of the apparatus main body M (right side in FIG. 1). The manual paper feed unit 64 is provided mainly for supplying the apparatus main body M with a paper T of a size and type different from the paper T set in the paper feed cassette 52. The manual paper feed unit 64 includes a manual feed tray 65 that forms part of the right side surface of the apparatus main body M in the closed state, and a paper feed roller 66. The lower end of the manual feed tray 65 is attached to the vicinity of the paper feed roller 66 so as to be rotatable (openable and closable). The paper T is placed on the open manual feed tray 65. The paper feed roller 66 feeds the paper T placed on the open manual feed tray 65 to the manual feed path La.

  A first paper discharge unit 50 a and a second paper discharge unit 50 b are provided on the upper side of the apparatus main body M. The first paper discharge unit 50a and the second paper discharge unit 50b discharge the paper T to the outside of the apparatus main body M (including the post-processing device and the job separator tray 410).

  The conveyance path L for conveying the paper T includes a first conveyance path L1 from the cassette paper feeding unit 51 to the secondary transfer nip N2, a second conveyance path L2 from the secondary transfer nip N2 to the fixing unit 9, and a fixing unit. 9 includes a third conveyance path L3 from the first branching section Q1 and a fourth conveyance path L4 from the first branching section Q1 to the first paper discharge section 50a. The conveyance path L includes a manual conveyance path La that joins the paper supplied from the manual sheet feeding unit 64 to the first conveyance path L1, a reverse conveyance path Lc from the first branching section Q1 to the reversing section Qb, and a reversal. The sheet transported on the transport path Lc is returned to the first transport path L1 via the second branching section Q2, and the sheet transported on the reverse transport path Lc is second discharged via the second branching section Q2. A sub-transport path Ld that transports to the section 50b, and a merging transport path Le that joins the paper T transported on the reversal transport path Lc to the fourth transport path L4 via the reversing section Qb and the third merging section P3.

  The return conveyance path Lb is a conveyance path that is provided to make the opposite surface (unprinted surface) opposite to the already printed surface to the intermediate transfer belt 7 when performing duplex printing on the paper T. According to the return conveyance path Lb, the paper T printed on one side is turned upside down and returned to the first conveyance path L1, and the upstream side of the registration roller pair 80 arranged on the upstream side of the secondary transfer roller 8 Can be conveyed. A predetermined toner image is transferred onto the unprinted surface in the secondary transfer nip N2 on the paper T that is reversed upside down by the return conveyance path Lb.

  A first junction P1 and a second junction P2 are provided in the middle of the first transport path L1. A third junction P3 is provided in the middle of the fourth transport path L4. A first branch portion Q1 is provided between the third transport path L3 and the fourth transport path L4. A second branch portion Q2 is provided in the middle of the reverse conveyance path Lc. A reversing unit Qb is provided in the vicinity of the reversing roller pair 430 in the reversing conveyance path Lc.

The first joining part P1 is a joining part where the manual feed path La joins the first transport path L1. The second junction P2 is a junction where the return conveyance path Lb merges with the first conveyance path L1. The third junction P3 is a junction where the junction conveyance path Le merges with the fourth conveyance path L4.
The first branch portion Q1 is a branch portion where the fourth transport path L4 and the reverse transport path Lc branch from the third transport path L3. The second branch portion Q2 is a branch portion where the sub transport path Ld branches from the reverse transport path Lc. The reversing unit Qb is a part where the conveyance direction of the paper T is reversed.

  The registration roller pair 80 is a roller pair for adjusting the skew (oblique feeding) of the paper T and the timing of toner image formation in the image forming unit GK. The registration roller pair 80 and a sensor (not shown) for detecting the paper T are provided in the middle of the first conveyance path L1 (specifically, between the second joining portion P2 and the secondary transfer roller 8). Be placed. The sensor is disposed immediately before the registration roller pair 80 in the transport direction of the paper T (upstream in the transport direction). The registration roller pair 80 conveys the paper T by performing the above-described correction and timing adjustment based on detection signal information from the sensor.

The curl correction roller pair 85 is a roller pair that constitutes a part of the curl correction apparatus 500, and corrects (reduces) the curl of the paper T. The curl correcting roller pair 85 corrects the curl of the paper T by inserting the paper T between the roller pair. The curl correcting roller pair 85 is disposed in the middle of the fourth transport path L4 (specifically, between the first branching portion Q1 and the third joining portion P3).
Details of the curl correction apparatus 500 will be described later.

The first paper discharge unit 50a is provided at the end of the fourth transport path L4. The first paper discharge unit 50 a is disposed on the upper side of the apparatus main body M. The first paper discharge unit 50a is open toward the left side surface of the apparatus main body M (left side in FIG. 1, opposite to the manual paper feed unit 64). The first paper discharge unit 50a discharges the paper T conveyed on the fourth conveyance path L4 to the outside of the apparatus main body M.
A post-processing device (not shown) can be connected to the opening side of the first paper discharge unit 50a. The post-processing device performs post-processing (stapling, punching, etc.) of the paper T discharged from the first paper discharge unit 50a.

The job separator 400 is provided with a second paper discharge unit 50b. The second paper discharge unit 50b is disposed on the upper side of the apparatus main body M. The second paper discharge section 50b opens toward the right side surface of the apparatus main body M (the right side in FIG. 1, the manual paper feed section 64 side). The second paper discharge unit 50b discharges the paper T sorted by the job separator 400 to the outside of the apparatus main body M (job separator tray 410).
A paper detection sensor is disposed at a predetermined position on each conveyance path.

  The job separator 400 is a part that performs a predetermined sorting process on the paper T, and is provided on the upper right side (right side in FIG. 1) of the apparatus main body M. For example, the job separator 400 performs a sorting process for discharging the paper T from the second paper discharge unit 50b. Further, the job separator 400 performs a process of reversing the transport direction of the paper T when performing duplex printing and when discharging the paper T from the second paper discharge unit 50b. In addition, when a sheet inserter (not shown) is optionally attached to the job separator 400, a sorting process for joining the paper T inserted from the sheet inserter into the job separator 400 to the fourth transport path L4. Do.

  The job separator 400 includes a job separator tray 410, a second discharge roller pair 420, a reverse roller pair 430, a first branch member 440, a second branch member 450, and a third branch member 460.

The job separator tray 410 is a tray that receives the paper T sorted by the job separator 400 and discharged from the second paper discharge unit 50b.
The second discharge roller pair 420 is a roller pair that is provided in the second paper discharge unit 50b and sends out the paper T reversed in the reversing unit Qb so as to be discharged from the second paper discharge unit 50b.

  The reversing roller pair 430 is a roller pair that is provided in the reversing part Qb and reverses the transport direction by sandwiching the paper T positioned in the reversing part Qb. When the sheet inserter is mounted on the job separator 400, the reverse roller pair 430 also functions as a feed roller that feeds the paper T inserted from the sheet inserter into the job separator 400 without changing the transport direction.

  The first branch member 440 is provided in the first branch portion Q1. The first branch member 440 branches (switches) the transport direction of the paper T transported on the third transport path L3 to the fourth transport path L4 or the reverse transport path Lc.

  The 2nd branch member 450 is provided in the inversion part Qb. The second branch member 450 branches (switches) the paper T transported on the reverse transport path Lc toward the upper side of the second branch member 450 or toward the fourth transport path L4. The space above the second branch member 450 functions as a reversing space for reversing the paper T sandwiched by the reversing roller pair 430.

  The third branch member 460 is provided in the second branch portion Q2. The third branching member 460 branches (switches) the transport direction of the paper T transported on the reverse transport path Lc toward the return transport path Lb or the sub transport path Ld. Further, when the sheet inserter is mounted on the job separator 400, the third branch member 460 branches (switches) the paper T transported on the sub transport path Ld toward the reverse transport path Lc.

Next, the operation of the copying machine 1 according to the first embodiment will be briefly described.
First, an image forming operation will be briefly described.
The image information read by the reading unit 301 is output to the apparatus main body M. The image information input to the apparatus main body M is input to an image formation control unit (not shown). The image formation control unit controls the photosensitive drums 2a to 2d, the charging units 10a to 10d, the laser scanner units 4a to 4d, the developing devices 16a to 16d, and the like constituting the image forming unit GK based on the image information. A predetermined toner image is formed on the photosensitive drums 2a, 2b, 2c, and 2d based on the image information.

  The toner images formed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially primary-transferred to the intermediate transfer belt 7 in the primary transfer nips N1a, N1b, N1c, and N1d. The toner image primarily transferred to the intermediate transfer belt 7 is secondarily transferred to the paper T conveyed through the conveyance path L in the secondary transfer nip N2. As a result, the same image as the original G is formed (copied) on the paper T. The paper T on which the image is formed is discharged outside the apparatus main body M from the first paper discharge unit 50a and the second paper discharge unit 50b.

Next, the transport operation of the paper T in each transport pattern will be described together with the image forming operation.
First, a description will be given of a transport operation when single-sided printing is performed on the paper T stored in the paper feed cassette 52 and transported to the first paper discharge unit 50a.

The paper T accommodated in the paper feed cassette 52 is sent out to the first transport path L1 by the forward feed roller 61 and the paper feed roller pair 63, and passes through the registration roller pair 80 and the intermediate transfer belt 7 and the secondary transfer roller. 8 (secondary transfer nip N2). The toner image is (secondarily) transferred to the paper T at the secondary transfer nip N2.
Thereafter, the sheet T is discharged from the secondary transfer nip N2 and introduced into the fixing nip between the heating rotator 9a and the pressure rotator 9b in the fixing unit 9 through the second transport path L2. Then, the toner melts in the fixing nip, and the toner is fixed on the paper T.

Next, the paper T is transported to the first paper discharge unit 50a through the third transport path L3 and the fourth transport path L4.
In this way, single-sided printing is performed on the paper T stored in the paper feed cassette 52, and the paper T on which single-sided printing has been performed is conveyed to the first paper discharge unit 50a.

Next, a conveying operation when performing single-sided printing on the paper T placed on the manual feed tray 65 will be described.
The paper T placed on the manual feed tray 65 is sent out to the manual feed path La by the paper feed roller 66, and is then transported to the registration roller pair 80 via the first joining portion P1 and the first transport path L1. . The subsequent operation is the same as that when printing on the paper T stored in the paper feed cassette 52, and the description thereof is omitted.

Next, a conveying operation when performing duplex printing will be described.
The same process as in the case of single-sided printing is performed until the paper T on which single-sided printing has been performed is discharged from the fixing unit 9. On the other hand, in the case of double-sided printing, the paper T on which single-sided printing has been performed is discharged from the fixing unit 9 and then transported through the third transport path L3 and transported toward the reverse transport path Lc at the first branching section Q1. Is done. Then, the paper T is conveyed in the reverse direction (the direction from the reverse roller pair 430 toward the second branch portion Q2) by the reverse roller pair 430 in the reverse portion Qb.

  The paper T conveyed in the reverse direction on the third conveyance path L3 is introduced into the return conveyance path Lb via the second branch portion Q2. The sheet T joins the first transport path L1 via the second joining portion P2. Here, the paper T is turned upside down from the one-side printing.

  Further, the paper T is introduced between the intermediate transfer belt 7 and the secondary transfer roller 8 via the first conveyance path L1. As described above, since the unprinted surface of the sheet T passes through the return conveyance path Lb and faces the secondary transfer roller 8, the toner image is transferred to the unprinted surface, and as a result, duplex printing is performed. The

Next, the conveyance operation when the paper T is discharged from the second paper discharge unit 50b will be described.
The process until the paper T is discharged from the fixing unit 9 is the same as that when the paper T is discharged from the first paper discharge unit 50a. On the other hand, when the paper T is discharged from the second paper discharge section 50b, the paper T discharged from the fixing section 9 is transported through the third transport path L3, and is moved to the reverse transport path Lc at the first branch section Q1. It is conveyed toward.

  Then, the paper T is conveyed in the reverse direction (the direction from the reverse roller pair 430 toward the second branch portion Q2) by the reverse roller pair 430 in the reverse portion Qb. The paper T that is transported in the reverse direction on the third transport path L3 is introduced into the sub transport path Ld via the second branch portion Q2. The paper T is discharged from the second paper discharge unit 50b.

Next, an operation in which the paper T inserted from the sheet inserter into the job separator 400 in a state where a sheet inserter (not shown) is mounted on the job separator 400 is discharged from the first paper discharge unit 50a will be described.
The paper T inserted from the sheet inserter into the job separator 400 is transported through the sub transport path Ld, and is transported through the reverse transport path Lc via the second branch portion Q2. Then, the sheet T is branched (switched) to the merging / conveying path Le by the second branching member 450 and merged into the fourth conveying path L4 via the third merging portion P3. Further, the paper T is discharged from the first paper discharge unit 50a.

  The sheet curl correction apparatus 500, which is a characteristic part of the copying machine 1 according to the first embodiment, will be described in detail below with reference to FIGS. The curl correction apparatus 500 includes the curl correction roller pair 85 described above, and corrects (reduces) the curl of the paper T by the curl correction roller pair 85.

  FIG. 2 is a perspective view illustrating a configuration of the curl correction unit 510 of the paper curl correction apparatus 500 in the copying machine 1 according to the first embodiment. FIG. 3 is a perspective view showing the configuration of the curl correction unit 510 in a state inverted by 180 ° with respect to FIG. FIG. 4 is a perspective view showing the configuration of the curl correction unit 510 from the hard roller 85b side. FIG. 5 is an enlarged vertical cross-sectional view of the main part showing the configuration of the curl correction unit 510. FIG. 6 is an enlarged longitudinal sectional view showing the start edge 85d and the end edge 85e of the nip portion 85c in the curl correction unit 510. As shown in FIG. FIG. 7 is an enlarged perspective view of a main part showing the configuration of the fixing member 520 on the apparatus main body side of the curl correction apparatus 500.

  FIG. 8 is a perspective view showing a state in which the curl correction unit 510 is assembled to the fixing member 520 on the apparatus main body side. FIG. 9 is an enlarged perspective view of a main part showing the configuration of a unit drive motor 540 that rotationally drives the curl correction unit 510. FIG. 10 is an enlarged perspective view of the main part showing the configuration of the roller drive motor 530 of the curl correction apparatus 500.

  As shown in FIGS. 2 to 10, the curl correction apparatus 500 according to the present embodiment includes a curl correction unit 510, a roller drive motor 530 as a second drive source, and a unit drive motor 540 as a first drive source. .

  As shown in FIG. 5, the curl correction unit 510 includes a curl correction roller pair 85 (85a, 85b), a third rotating shaft 511 (see FIGS. 2 and 3), a pair of support members 512, 512, A sheet introduction guide path 570 as a sheet introduction guide path and a sheet lead-out guide path 580 as a sheet lead-out guide path are provided. The curl correcting roller pair 85 includes a soft roller 85a as a first roller and a hard roller 85b as a second roller.

  As shown in FIGS. 2 to 5, the third rotation shaft 511 extends in parallel with the first rotation shaft 551 of the first curl correction roller 85a and the second rotation shaft 561 of the second curl correction roller 85b. . The second rotation shaft 561 is an axis parallel to the axial direction of the first rotation shaft 551. The third rotation shaft 511 protrudes outward in the axial direction Y from the center of each outer surface of the pair of support members 512 and 512 outward.

  The pair of support members 512 and 512 rotatably support the curl correction roller pair 85. The support member 512 is formed in a disk shape. The pair of support members 512 and 512 can rotate around the center of the third rotation shaft 511. The curl correcting unit 510 uses the curl correcting roller pair 85 by rotating the pair of support members 512 and 512 around the center of the third rotation shaft 511 in the forward or reverse direction over an angular range of about 180 °. The curl correction direction (the direction for correcting the upper curl and the direction for correcting the lower curl) can be changed.

  The paper introduction guide path 570 guides the paper T to be introduced between the curl correction roller pair 85 from the upstream side of the fourth transport path L4. The paper lead-out guide path 580 guides the paper T that has passed between the curl correction roller pair 85 so as to be guided downstream of the fourth transport path L4.

  As shown in FIGS. 2, 3 and 8, the soft roller 85a is formed of a flexible material such as synthetic resin, for example, an elastic member. This elastic member is made of an elastically deformable material such as rubber or sponge. A plurality of soft rollers 85a are arranged at a substantially constant interval in the axial direction Y of the first rotation shaft 551 (the width direction of the paper T), and are fixed to the first rotation shaft 551, respectively. That is, the soft roller 85a rotates around the first rotation shaft 551. The term “width direction of the sheet T (sheet)” means a direction orthogonal to the sheet conveyance direction.

  The interval between the elastic members forming the soft roller 85a is determined according to the width dimension of the sheet on which the curl correction process is performed, and may be constant or not constant, for example. The elastic member forming the soft roller 85a may be a cylindrical elastic member that continuously surrounds the first rotation shaft 551.

As shown in FIGS. 5 and 6, the plurality of soft rollers 85 a are pressed against the outer peripheral surface of the hard roller 85 b so that the outer peripheral portion is recessed toward the first rotation shaft 551. That is, the hard roller 85b is pressed into contact with the soft roller 85a so as to form a curved nip portion 85c through which the paper T passes. The “nip portion” means a boundary between a pair of rollers that are pressed against each other.
As a result, the peripheral surface of the soft roller 85a that is in contact with the hard roller 85b becomes a deformed surface that is elastically deformed inward (in the direction toward the first rotation shaft 551), and a curved nip portion 85c is formed. While the paper T passes through the nip portion 85c, the curl of the paper T is corrected.

The second rotation shaft 561 of the hard roller 85b is connected to the roller drive motor 530. Therefore, the hard roller 85b is rotationally driven by the roller drive motor 530.
In the axial direction Y, the direction in which the roller drive motor 530 and the unit drive motor 540 are arranged is also referred to as “Y1 direction” (Y1 side). The direction opposite to the Y1 direction is also referred to as “Y2 direction” (Y2 side).

  The hard roller 85b is formed from a hard material such as metal. The hard roller 85b is a cylindrical roller that is formed to be harder than the elastic member that forms the soft roller 85a. As shown in FIG. 4, the hard roller 85b is a long roller having an outer peripheral surface having the same outer diameter over substantially the entire length in the axial direction Y (the width direction of the paper T) of the second rotation shaft 561. The hard roller 85b extends between the two support members 512 substantially parallel to the soft roller 85a. The hard roller 85b rotates around the second rotation shaft 561. The diameter of the soft roller 85a is larger than the diameter of the hard roller 85b. With the rotational driving of the soft roller 85a pressed against the outer peripheral surface of the hard roller 85b, the soft roller 85a is driven (rotated) in the opposite direction to the hard roller 85b.

  A pair of support members 512 are arranged in a state of being opposed to each other at both ends in the axial direction Y of the first rotation shaft 551 and the second rotation shaft 561. The curl correction roller pair 85 (85a, 85b) is rotatably supported between the pair of support members 512 and 512. In addition, a pair of upper and lower long plate members 571 and 572 that form the paper introduction guide path 570 and a pair of upper and lower long plates that form the paper guide path 580 are formed between the opposing inner surfaces of the pair of support members 512 and 512. The members 581 and 582 are stretched and fixed. As the pair of support members 512 and 512 rotate, the positions of the paper introduction guide path 570 and the paper lead-out guide path 580 are interchanged (see FIGS. 11 and 12).

  The long plate members 571, 572, 581 and 582 extend straight in a substantially horizontal direction. As shown in FIGS. 5 and 6, the long plate member 572 bends in the direction away from the long plate member 571 from the inside to the outside of the support member 512. The long plate member 582 is bent in the direction away from the long plate member 581 from the inside to the outside of the support member 512.

  The long plate member 571 and the long plate member 572 form a paper introduction guide path 570 that narrows toward a contact portion (nip portion 85c) between the soft roller 85a and the hard roller 85b. The long plate member 581 and the long plate member 582 form a paper lead-out guide path 580 extending from the nip portion 85c.

  In the following description, of the edges of the nip portion 85c of the curl correction apparatus 500, an edge that receives the paper T toward the nip portion 85c is referred to as a “start edge 85d”, and an edge from which the paper T that has passed through the nip portion 85c is discharged. Is referred to as “terminal edge 85e”. The “first position” refers to a position at which the paper T toward the nip portion 85c is received from the start edge 85d side of the nip portion 85c. The “second position” refers to a position where the paper T toward the nip portion 85c is received from the end edge 85e side of the nip portion 85c.

However, these terms are merely convenient terms for clarifying the explanation, and do not limit the present invention. Therefore, of the edges of the nip portion 85c of the curl correction apparatus 500 at the second position, the edge that receives the paper T toward the nip portion 85c is referred to as a “start edge 85d”, and the paper T that has passed through the nip portion 85c is discharged. The edge may be referred to as a “terminal edge 85e”.
In the following description, when the curl correction apparatus 500 is in the first position, the start edge 85d is an edge that receives the paper T toward the nip portion 85c, and the terminal edge 85e is the paper T that has passed through the nip portion 85c. It becomes the edge to be discharged.

As shown in FIGS. 5, 6, and 12, the curl correction apparatus 500 in the first position can correct the curl of the paper T that has been curled upward. The upper curled paper T passes through a nip portion 85c formed between the soft roller 85a and the hard roller 85b along the upwardly curved deformation surface. As a result, the downward bending amount of the paper T is reduced.
On the other hand, as shown in FIG. 11, when the curl correction apparatus 500 is in the second position, the hard roller 85b is located above the soft roller 85a, so that the deformation surface (nip portion 85c) is curved downward. Therefore, the curl correction apparatus 500 in the second position corrects the curl of the lower curled paper T.

  The third rotation shaft 511 includes a first surface (horizontal plane) H that passes through the start edge 85d and the termination edge 85e, and a second surface (vertical surface) V that passes through the first rotation shaft 551 and the second rotation shaft 561. It extends in line with the intersection line. In other words, the third rotation shaft 511 extends in parallel to the axial direction of the first rotation shaft 551 within the surface of the first surface H including the start edge 85d and the end edge 85e of the nip portion 85c. The third rotation shaft 511 is formed along an intersection line between the first surface H and the second surface V including the first rotation shaft 551 and the second rotation shaft 561.

  When the third rotation shaft 511 is formed along the intersecting line between the first surface H and the second surface V, as shown in FIGS. 6, 11, and 12, the curl correction device 500 in the first position is used. The positional relationship between the paper introduction guide path 570 and the fourth conveyance path L4 formed upstream of the curl correction apparatus 500 (the distance between the paper introduction guide path 570 and the fourth conveyance path L4 in the conveyance direction of the paper T). , And the distance between the paper introduction guide path 570 and the fourth transport path L4 in the direction orthogonal to the surface of the transported paper T) is the same as the paper lead-out guide path 580 of the curl correction apparatus 500 at the second position. Positional relationship with the fourth transport path L4 (the distance between the paper guide path 580 and the fourth transport path L4 in the transport direction, and the paper guide path 580 in the direction orthogonal to the surface of the transported paper T) Approximately equal to the distance to the fourth transport path L4) Kunar.

  Similarly, the positional relationship between the sheet lead-out guide path 580 of the curl correction apparatus 500 in the first position and the fourth transport path L4 formed downstream of the curl correction apparatus 500 (the sheet lead-out guide path 580 in the transport direction). The distance between the fourth transport path L4 and the distance between the paper guide path 580 and the fourth transport path L4 in the direction orthogonal to the surface of the transported paper T) is the curl at the first position. The positional relationship between the paper introduction guide path 570 and the fourth transport path L4 of the correction device 500 (the distance between the paper introduction guide path 570 and the fourth transport path L4 in the transport direction and the surface of the paper T to be transported) (Distance between the paper introduction guide path 570 and the fourth transport path L4 in the orthogonal direction).

  Accordingly, when receiving the paper T from the start edge 85d side to the nip portion 85c (first position), the conveyance condition of the paper T upstream of the curl correction device 500 is that the paper T going from the end edge 85e side to the nip portion 85c is used. When receiving (second position), the conveyance condition of the paper T upstream of the curl correction apparatus 500 is substantially equal. Similarly, when the paper T on which curl correction has been performed from the start edge 85d is discharged (second position), the conveyance condition of the paper T downstream of the curl correction device 500 is that curl correction has been performed from the end edge 85e. When the paper T is discharged (first position), the conveyance condition of the paper T downstream of the curl correction apparatus 500 is substantially equal.

  Therefore, even if the direction of correcting the curl of the paper T is changed, the transport condition of the paper T is kept constant. When the third rotation shaft 511 extends in the direction (parallel direction) along the first rotation shaft 551 and the second rotation shaft 561 in the plane of the first surface H, the surface of the paper T to be transported is orthogonal. The distance between the sheet introduction guide path 570 and / or the sheet lead-out guide path 580 in the direction and the fourth transport path L4 is kept substantially constant. Therefore, the third rotation shaft 511 may be formed at an arbitrary position within the surface of the first surface H.

  Note that the displacement of the third rotation shaft 511 from the line of intersection of the first surface H and the second surface V appears as a displacement amount of the curl correction apparatus 500 in the transport direction of the paper T. Therefore, as shown in FIG. 6, the third rotating shaft 511 is formed between a pair of intersections formed by the circumscribed circle S of the soft roller 85a and the hard roller 85b and the first surface H (the distance between the intersections in FIG. 6). (Denoted by J).

  The apparatus body M is provided with a pair of fixing members 520 (only one is shown in FIG. 8) having a bearing hole 521 (see FIG. 7). By inserting both end portions of the third rotating shaft 511 into the bearing hole portions 521 of the pair of fixing members 520, the pair of support members 512 and 512 can move the third rotating shaft 511 between the pair of fixing members 520. It is supported rotatably around the center.

The fixing members 520 are disposed on both end sides (Y1 side, Y2 side) in the axial direction Y of the curl correction roller pair 85 in the curl correction unit 510, and are fixed to the apparatus main body M. The roller drive motor 530 and the unit drive motor 540 are fixedly disposed on the outer surface side of one fixing member 520 disposed on one end side (Y1 side) in the axial direction Y.
The other fixing member (not shown) has the same shape and size as the one fixing member 520. The other fixing member has only a bearing hole portion that rotatably supports the other end portion (Y2 side) of the third rotating shaft 511 in the support member 512.

  As shown in FIG. 7, a pinion gear 532 and a pinion gear 542 are arranged on the fixing member 520 so as to protrude inward (Y2 direction). The pinion gear 532 is fixed to the output shaft 531 of the roller drive motor 530. The pinion gear 542 is fixed to the output shaft 541 of the unit drive motor 540. On the inner surface of the fixing member 520, a rotation control component 535 of both the drive motors 530 and 540 is attached.

  As shown in FIGS. 2, 3, and 8 to 10, the outer peripheral gear 514 is fixed to the outer side (one end side, Y1 side) in the axial direction Y of the support member 512 via a plurality of support members 513. Has been supported. The outer peripheral gear 514 is connected to the support member 512 so as not to rotate. The outer peripheral gear 514 is a partial gear having a tooth portion formed over a range of about 270 ° at the rotation center angle and a notch 516 formed in the remaining range of about 90 °. The outer peripheral gear 514 rotatably supports an intermediate gear 515 as an input gear and has a peripheral surface on which gear teeth are formed. The third rotation shaft 511 of the support member 512 defines the center of the fan-shaped outer peripheral gear 514.

As shown in FIG. 3, the intermediate gear 515 is fixed to the third rotating shaft 511 of the curl correction unit 510. The intermediate gear 515 is a gear that meshes with a pinion gear 532 fixed to the output shaft 531 of the roller drive motor 530. That is, the intermediate gear 515 receives the rotational force from the roller drive motor 530.
One end portion of the second rotation shaft 561 of the hard roller 85 b in the curl correction unit 510 extends to the outside of the support member 512. A hard gear rotating first gear 552 is fixed to the extended rotation shaft portion 561a. The first gear 552 is connected to the end of the hard roller 85b on the unit drive motor 540 side.

  The two-stage gear 553 serving as a relay gear includes a third gear 553 a serving as a small gear portion meshing with the intermediate gear 515 and a second gear 553 b serving as a large gear portion meshing with the first gear 552. The third gear 553a and the second gear 553b rotate coaxially. The two-stage gear 553 is rotatably held by the support member 512. The third gear 553 a of the two-stage diameter gear 553 is disposed in the notch 516 of the outer peripheral gear 514. Accordingly, the roller drive motor 530 rotationally drives the hard roller 85b of the curl correction roller pair 85 via the pinion gear 532, the intermediate gear 515, the two-stage gear 553, and the first gear 552.

  As shown in FIGS. 9 and 10, a gear holding frame 590 is fixed to the inner surface side (Y2 side) of the fixing member 520. The gear holding frame 590 is provided with a fixed shaft 591 fixed so as to protrude, and is provided with a through hole 592. The through hole 592 is a hole for projecting the output shaft 531 and the pinion gear 532 to the curl correction unit 510 side.

  A two-stage gear 543 is held on the fixed shaft 591 of the gear holding frame 590 so as to be rotatable around the center of the fixed shaft 591. The two-stage gear 543 includes a large-diameter gear portion 543 a and a small-diameter gear portion 543 b that meshes with the outer peripheral gear 514. The large-diameter gear portion 543a is a gear portion that meshes with a pinion gear 542 fixed to the output shaft 541 of the unit drive motor 540. Thus, the unit drive motor 540 is connected to the outer peripheral gear 514 via the pinion gear 542, the two-stage diameter gear 543, and the outer peripheral gear 514, and the support member 512 of the curl correction unit 510 is moved around the third rotation shaft 511. It is driven to rotate in the forward direction or the reverse direction over an angular range of 180 °.

  The unit drive motor 540 has a first position for receiving the paper T toward the nip portion 85c from the start edge 85d side of the nip portion 85c, and a second position for receiving the paper T toward the nip portion 85c from the end edge 85e side of the nip portion 85c. The support member 512 is rotated in between.

Next, the operation of the curl correction apparatus 500 will be described with reference to FIGS. 11 and 12.
FIG. 11 is an enlarged longitudinal sectional view of a main part for explaining a state where the curl correction unit 510 is rotated so that the curl correction direction by the curl correction roller pair 85 is the first direction. FIG. 12 is an enlarged longitudinal sectional view of a main part for explaining a state where the curl correction unit 510 is rotated so that the curl correction direction by the curl correction roller pair 85 is the second direction.

  When the paper T that has been brought into the state of lower curl due to fixing by the fixing unit 9 is transported through the fourth transport path L4, the unit drive motor 540 is driven in the clockwise direction. The rotational driving force is transmitted to the support member 512 of the curl correction unit 510 via the pinion gear 542, the two-stage diameter gear 543, and the outer peripheral gear 514. As a result, the support member 512 of the curl correction unit 510 is driven to rotate around the third rotation shaft 511 in the direction of the arrow R1. As a result, the curl correction direction by the curl correction roller pair 85 is set (changed) to a direction corresponding to the lower curl.

  That is, as shown in FIG. 11, the soft roller 85a of the curl correction roller pair 85 is positioned lower than the fourth transport path L4. On the other hand, the hard roller 85b is positioned higher than the fourth transport path L4. Further, the paper introduction guide path 570 is disposed on the upstream side of the fourth transport path L4. On the other hand, the sheet lead-out guide path 580 is disposed on the downstream side of the fourth transport path L4. In this state, the rotation of the curl correction unit 510 is stopped.

  At the same time or immediately after the driving of the unit driving motor 540, the roller driving motor 530 is also driven. The rotational driving force is transmitted to the hard roller 85b of the curl correction roller pair 85 via the pinion gear 532, the intermediate gear 515, the two-stage diameter gear 553, and the first gear 552. As a result, the hard roller 85b is driven to rotate in the direction of the arrow r1, and the soft roller 85a is driven to rotate.

  In this state, the paper T conveyed through the fourth conveyance path L4 is introduced between the curl correction roller pair 85 through the paper introduction guide path 570 and passes between the curl correction roller pair 85. During this passage, the upper convex portion Ta of the paper T is pushed deeper toward the soft roller 85a by the hard roller 85b, so that the lower curl of the paper T is corrected. The sheet T after the correction of the lower curl is carried out to the downstream side of the fourth transport path L4 through the sheet guide path 580.

  Next, when the paper T that has been brought into the upper curl state by the fixing by the fixing unit 9 is transported through the fourth transport path L4, the unit drive motor 540 is driven counterclockwise. The rotational driving force is transmitted to the support member 512 of the curl correction unit 510 via the pinion gear 542, the two-stage diameter gear 543, and the outer peripheral gear 514. As a result, the support member 512 of the curl correction unit 510 is driven to rotate around the third rotation shaft 511 in the direction of the arrow R2. As a result, the curl correction direction by the curl correction roller pair 85 is set (changed) to a direction corresponding to the upper curl.

  That is, as shown in FIG. 12, the soft roller 85a of the curl correction roller pair 85 is positioned higher than the fourth conveyance path L4. On the other hand, the hard roller 85b is located at a position lower than the fourth transport path L4. Further, the sheet lead-out guide path 580 whose positions are switched with each other in accordance with the rotation of the curl correction unit 510 is disposed on the upstream side of the fourth transport path L4. On the other hand, the paper introduction guide path 570 is disposed on the downstream side of the fourth transport path L4. In this state, the rotation of the curl correction unit 510 is stopped.

  When the curl correction direction is changed to the direction corresponding to the upper curl by driving the unit drive motor 540, the roller drive motor 530 is driven simultaneously or immediately after. The rotational driving force is transmitted to the hard roller 85b of the curl correction roller pair 85 via the pinion gear 532, the intermediate gear 515, the two-stage diameter gear 553, and the first gear 552. As a result, the hard roller 85b is driven to rotate in the direction of the arrow R2, and the soft roller 85a is driven to rotate.

  In this state, the sheet T conveyed through the fourth conveyance path L4 is introduced between the curl correction roller pair 85 through the sheet guide path 580 switched to the role of the sheet introduction guide path, and is used for curl correction. Pass between the roller pair 85. During this passage, the downward convex portion Tb of the paper T is pushed deeper toward the soft roller 85a by the hard roller 85b, so that the upper curl of the paper T is corrected. The paper T after the correction of the upper curl is carried out to the downstream side of the fourth transport path L4 through the paper introduction guide path 570 switched to the role of the paper lead-out guide path.

According to the paper curl correction apparatus 500 in the copying machine 1 of the first embodiment described above, for example, the following effects are exhibited.
The straightening device 500 of the first embodiment rotates around the first rotation shaft 551 and is elastically deformable with a soft roller 85a and a second rotation shaft 561 parallel to the axial direction of the first rotation shaft 551. A hard roller 85b that is formed to be harder than the soft roller 85a, a support member 512 that supports the soft roller 85a and the hard roller 85b, and a support member 512 that rotates around the third rotation shaft 511. The unit drive motor 540 to be driven, the first gear 552 connected to the end of the hard roller 85b on the unit drive motor 540 side, the second gear 553b meshing with the first gear 552, and the second gear 553b rotating coaxially. Three gears 553a, an intermediate gear 515 that meshes with the third gear 553a, and a roller drive motor 5 that transmits rotational force to the intermediate gear 515. Including 0 and, the. The hard roller 85b is pressed against the soft roller 85a so that a curved nip portion 85c through which the paper T passes is formed between the hard roller 85b and the soft roller 85a. The third rotating shaft 511 extends in parallel with the axial direction of the first rotating shaft 551 within the plane of the first surface H including the start edge 85d and the end edge 85e of the nip portion 85c. The unit drive motor 540 receives the support member 512 from the first end edge 85d side of the nip portion 85c at the first position where the paper T toward the nip portion 85c is received, and the end edge 85e side of the nip portion 85c. Rotate between the second position to receive from.

  Therefore, according to the first embodiment, the soft roller 85a and the hard roller 85b rotate together and hardly inhibit the movement of the paper T passing through the nip portion 85c. The curved nip portion 85c corrects the curl of the paper T passing through the nip portion 85c. The soft roller 85a and the hard roller 85b are supported by a support member 512. The unit drive motor 540 rotates the support member 512 around the third rotation shaft 511 between the first position and the second position.

At the first position, the sheet T that is directed from the start edge 85d side of the nip portion 85c toward the nip portion 85c is received. In the second position, the sheet T is received from the end edge 85e side of the nip portion 85c toward the nip portion 85c. The third rotation shaft 511 of the support member 512 is along the axial direction of the first rotation shaft 551 or the second rotation shaft 561 within the first surface H including the start edge 85d and the end edge 85e of the nip portion 85c. Extend.
Therefore, when the support member 512 is in the first position and when the support member 512 is in the second position, the amount of displacement between the start edge 85d and the end edge 85e in the direction crossing the surface of the paper T is reduced. Therefore, the curl of the paper T can be corrected using the two rollers (the soft roller 85a and the hard roller 85b), so that the curl correcting device 500 can be reduced in size.

Further, the curl correction apparatus 500 of the first embodiment includes a first gear 552 connected to an end of the hard roller 85b on the unit drive motor 540 side, a second gear 553b that meshes with the first gear 552, and a second gear. It is driven using a third gear 553a that rotates coaxially with 553b, an intermediate gear 515 that meshes with the third gear 553a, and a roller drive motor 530 that transmits rotational force to the intermediate gear 515.
Therefore, since the unit drive motor 540 and the roller drive motor 530 are positioned on the same end side, the overall length of the curl correction device 500 is shortened, and the curl correction device 500 can be further downsized. In addition, the power supply path to the unit drive motor 540 and the roller drive motor 530 is relatively simplified, and a practical curl correction apparatus 500 is provided.

The first embodiment further includes an outer peripheral gear 514 that rotatably supports the intermediate gear 515 and has a peripheral surface on which gear teeth are formed. The outer peripheral gear 514 is relative to the support member 512. The unit drive motor 540 is connected to the outer peripheral gear 514 so as not to rotate.
Therefore, in the first embodiment, the unit drive motor 540 transmits power to the outer peripheral gear 514. The outer peripheral gear 514 is connected to the support member 512 in a relatively non-rotatable manner. Therefore, the outer peripheral gear 514 and the support member 512 rotate together, and the curl correction direction is preferably changed. Further, the outer peripheral gear 514 covers the first gear 552, the second gear 553b, the third gear 553a, and the intermediate gear 515, so that a relatively safe curl correction apparatus 500 is provided.

  In the first embodiment, the third rotation shaft 511 is formed along the line of intersection between the first surface H and the second surface V including the first rotation shaft 551 and the second rotation shaft 561. Therefore, according to the first embodiment, since the amount of eccentricity of the rotation of the support member 512 is reduced, the curl correction device 500 can be further downsized.

  Further, the curl correction apparatus 500 of the first embodiment supports the curl correction roller pair 85 and the curl correction roller pair 85 to be rotatable, and the first rotation shaft 551 and the second rotation shaft 551 of the curl correction roller pair 85. And a support member 512 rotated around a third rotation shaft 511 parallel to the rotation shaft 561. By rotating the support member 512, the curl correction direction by the curl correction roller pair 85 can be changed. A straightening unit 510, a roller drive motor 530 that rotationally drives the curl correction roller pair 85, and a unit drive motor 540 that rotationally drives the support member 512 of the curl correction unit 510 are provided. The roller drive motor 530 and the unit drive motor 540 are provided on a fixing member 520 on the apparatus main body M side that rotatably supports the curl correction unit 510.

  Therefore, the weight of the roller drive motor 530 can be borne by the fixing member 520 on the apparatus main body M side. This eliminates the need to burden the curl correction unit 510 with the weight of the roller drive motor 530 and the space occupied by the roller drive motor 530. Accordingly, the curl correction unit 510 can be reduced in weight and size. Further, the rotational load of the unit drive motor 540 is also reduced, and the power consumption required for changing the curl correction direction by the rotational drive of the curl correction unit 510 can be reduced.

  In addition, a part of the electric wire for supplying power to the roller drive motor 530 and the control unit do not enter the curl correction unit 510. Therefore, for example, it is easy to pull out the curl correction unit 510 from the inside of the apparatus body M for jam processing and the like, and the maintenance is excellent.

In the curl correction apparatus 500 of the first embodiment, the roller drive motor 530 and the unit drive motor 540 are on one end side (Y1 side) in the axial direction Y of the curl correction roller pair 85 in the curl correction unit 510. Is arranged.
Therefore, when the curl correction unit 510 is pulled out from the inside of the apparatus main body M, it can be pulled out in a direction in which the drive motors 530 and 540 are not arranged. Accordingly, the curl correction unit 510 can be pulled out without being disturbed by any of the drive motors 530 and 540, and maintenance can be performed more easily and efficiently.

  Further, in the curl correction apparatus 500 of the first embodiment, the support member 512 in the curl correction unit 510 has an outer peripheral gear 514, and the curl correction unit 510 is an intermediate gear 515 fixed to the third rotation shaft 511. The unit drive motor 540 is configured to rotationally drive the support member 512 via the outer peripheral gear 514, and the roller drive motor 530 is configured to rotationally drive the curl correction roller pair 85 via the intermediate gear 515. ing.

  Therefore, the curl correction unit 510 is fixed to the fixing member 520 on the apparatus main body M side from one end side (Y1 side) in the axial direction Y of the first rotation shaft 551 and the second rotation shaft 561 of the curl correction roller pair 85. When inserting toward the member 520, the gears on both the drive motors 530 and 540 provided on the fixed member 520 side and the outer peripheral gear 514 and the intermediate gear 515 on the curl correction unit 510 side can be simultaneously meshed. It becomes possible. This can reduce the number of steps when assembling the curl correction apparatus 500 to the apparatus main body M, and can also easily and efficiently perform the pull-out operation and the insertion operation of the curl correction unit 510 during maintenance such as jam processing.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 13 is an enlarged perspective view of a main part showing the configuration of a single drive motor 600 for rotating the curl correction unit 510 of the paper curl correction apparatus 500A in the copier 1 according to the second embodiment of the present invention and the surroundings. It is. FIG. 14 is an enlarged plan view of the main part showing the configuration of a single drive motor 600 for rotating the curl correction unit 510 of the paper curl correction apparatus 500A in the copier 1 of the second embodiment and its peripheral configuration.

  The curl correction apparatus 500A of the second embodiment is different from the curl correction apparatus 500 of the first embodiment in that the rotation drive of the curl correction unit 510 and the rotation drive of the curl correction roller pair 85 are the rotation of a single drive motor 600. This is mainly different in that it is performed by switching the direction. The second embodiment will be described mainly with respect to differences from the first embodiment. The same components as those in the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted. For the points not specifically described in the second embodiment, the description of the first embodiment is appropriately applied or adopted.

  As shown in FIGS. 13 and 14, in the curl correction apparatus 500A of the second embodiment, the rotation drive of the curl correction unit 510 and the rotation drive of the curl correction roller pair 85 are provided on the outer surface of the fixing member 620 on the apparatus main body M side. A single drive motor 600 that performs (also serves as) is installed in a fixed state.

  The output shaft 601 of the drive motor 600 protrudes inward (Y2 direction) of the fixed member 620. A pinion gear 610 is fixed to the projecting output shaft 601. A gear 611 that meshes with the pinion gear 610 is rotatably supported by the fixed member 620 via a support shaft 612. An intermediate gear 515 is engaged with the gear 611. The intermediate gear 515 is a gear rotatably supported on the third rotation shaft 511 of the support member 512 in the curl correction unit 510. The intermediate gear 515 meshes with the third gear 553 a of the two-stage diameter gear 553. The two-stage gear 553 also has a second gear 553b that meshes with the first gear 552 for rotating the hard roller.

  The support shaft 612 of the gear 611 protrudes from the fixed member 620 toward the curl correction unit 510 side (Y2 side). The protruding end portion of the support shaft 612 is rotatably supported by a fixed plate member 622 disposed inside the fixed member 620 via a bearing 621. A curl correction unit rotation direction switching gear 616 and a torque limiter 630 are concentrically and rotatably fitted to the support shaft 612.

  The torque limiter 630 is configured such that a cylindrical housing 631 and an inner ring 632 are fitted so as to be relatively rotatable with a sliding member (not shown) made of a hard ring and a magnet interposed therebetween. The inner ring 632 is disposed inside the cylindrical housing 631. The housing 631 is engaged with the curl correction unit rotation direction switching gear 616 and rotates integrally therewith. Further, the inner ring 632 and the support shaft 612 are connected to each other so as to be integrally rotatable via a pin 614 protruding from the support shaft 612 side and a pin engaging recess 615 formed on the inner ring 632 side.

  The curl correction unit rotation direction switching gear 616 meshes with an outer peripheral gear (partial gear) 514. The outer peripheral gear 514 is fixed to and supported by the support member 512 in the curl correction unit 510 via a plurality of support members 513.

Next, the curl correction direction changing operation in the curl correction apparatus 500A according to the second embodiment configured as described above will be described.
When the paper T that has been in a state of exhibiting a lower curl due to fixing by the fixing unit 9 is transported through the fourth transport path L4, when the single drive motor 600 is rotationally driven in the forward direction, the rotational driving force is , And transmitted to the gear 611 via the pinion gear 610. Thereby, the support shaft 612 is rotated. When the support shaft 612 is rotated, the rotation is transmitted to the inner ring 632 of the torque limiter 630 through the pin 614 and the pin engaging recess 615. The rotation of the inner ring 632 is transmitted to the housing 631 via a sliding member (not shown) of the torque limiter 630. Thereby, the curl correction unit rotation direction switching gear 616 rotates in the forward direction. As a result, the rotation of the curl correction unit rotation direction switching gear 616 is transmitted to the outer peripheral gear 514. Thereby, the support member 512 of the curl correction unit 510 is rotationally driven around the third rotation shaft 511 in the direction of the arrow R1 (see FIG. 11). As a result, the curl correction direction by the curl correction roller pair 85 is changed toward the direction corresponding to the lower curl.

  At the same time, the rotation of the gear 611 is transmitted to the hard roller 85 b of the curl correction roller pair 85 via the two-stage gear 553 and the first gear 552. As a result, the hard roller 85b is rotationally driven in the direction of the arrow r1 (see FIG. 11), and the soft roller 85a is driven to rotate.

  When the support member 512 of the curl correction unit 510 is operated (rotated) so that the curl correction direction by the curl correction roller pair 85 is changed to the position corresponding to the lower curl (state of FIG. 11), the curl A predetermined load is applied to the correction unit rotation direction switching gear 616 and the housing 631 of the torque limiter 630. When a predetermined load is applied, slip occurs between the housing 631 and the inner ring 632 of the torque limiter 630, and the rotation of the support shaft 612 is not transmitted to the housing 631. Therefore, the rotation of the curl correction unit rotation direction switching gear 616 is stopped. Even in this state, the rotation of the gear 611 is continuously transmitted to the hard roller 85 b of the curl correction roller pair 85 via the two-stage gear 553 and the first gear 552. Thereby, the rotational drive of the hard roller 85b in the direction of the arrow r1 and the driven rotation of the soft roller 85a are maintained, and the correction of the lower curl is performed as prescribed.

  Further, when the paper T that has been curled up by the fixing unit 9 is transported through the fourth transport path L4, when the drive motor 600 is rotationally driven in the reverse direction, the rotational driving force is It is transmitted to the gear 611 via the pinion gear 610. Thereby, the support shaft 612 is rotated. When the support shaft 612 is rotated, the rotation is transmitted to the inner ring 632 of the torque limiter 630 through the pin 614 and the pin engaging recess 615. The rotation of the inner ring 632 is transmitted to the housing 631 via a sliding member (not shown) of the torque limiter 630. Thereby, the curl correction unit rotation direction switching gear 616 is rotated in the reverse direction. As a result, the rotation of the curl correction unit rotation direction switching gear 616 is transmitted to the outer peripheral gear 514. Accordingly, the support member 512 of the curl correction unit 510 is rotationally driven around the third rotation shaft 511 in the direction of arrow R2 (see FIG. 12). As a result, the curl correction direction by the curl correction roller pair 85 is changed toward the direction corresponding to the upper curl.

  At the same time, the rotation of the gear 611 is transmitted to the hard roller 85 b of the curl correction roller pair 85 via the two-stage gear 553 and the first gear 552. As a result, the hard roller 85b is rotationally driven in the direction of the arrow r2 (see FIG. 12), and the soft roller 85a is driven to rotate.

  When the support member 512 of the curl correction unit 510 is operated so that the curl correction direction by the curl correction roller pair 85 is changed to the position corresponding to the upper curl (state of FIG. 12), the curl correction unit is rotated. A predetermined load is applied to the direction switching gear 616 and the housing 631 of the torque limiter 630. When a predetermined load is applied, slip occurs between the housing 631 and the inner ring 632 of the torque limiter 630, and the rotation of the support shaft 612 is not transmitted to the housing 631. Therefore, the rotation of the curl correction unit rotation direction switching gear 616 is stopped. Even in this state, the rotation of the gear 611 is continuously transmitted to the hard roller 85 b of the curl correction roller pair 85 via the two-stage gear 553 and the first gear 552. Thereby, the rotational drive of the hard roller 85b and the driven rotation of the soft roller 85a in the direction of the arrow r2 are maintained, and the upper curl is corrected as prescribed.

According to the curl correction apparatus 500A of the second embodiment described above, the following effects can be obtained in addition to the effects shown in the first embodiment.
In the curl correction apparatus 500A of the second embodiment, the rotation drive of the curl correction roller pair 85 by the roller drive motor 530 and the rotation drive of the curl correction unit 510 by the first drive source are the rotation directions of the single drive motor 600. Is performed by switching to the forward rotation direction or the reverse rotation direction.

  That is, both the rotation drive of the curl correction roller pair 85 and the rotation drive of the curl correction unit 510 can be performed at the same time by simply switching the rotation direction of the single drive motor 600 to the normal rotation direction or the reverse rotation direction. Is possible. Therefore, the entire structure of the curl correction apparatus 500 can be simplified, and weight reduction, size reduction, cost reduction, and the like can be achieved. Further, since the operation of one drive motor 600 is sufficient, there is little loss of power consumption, and further power saving can be achieved.

As mentioned above, although preferred embodiment of this invention was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above.
For example, in the first embodiment described above, both the roller drive motor 530 and the unit drive motor 540 are disposed on one end side (Y1 side) in the axial direction Y of the curl correction roller pair 85 in the curl correction unit 510. However, it is not limited to this. Both drive motors 530 and 540 may be arranged separately on both end sides (Y1 side and Y2 side) in the axial direction Y.
The roller drive motor 530 may rotationally drive both the hard roller 85b and the soft roller 85a, or may drive only the soft roller 85a.

  Instead of the outer peripheral gear 514 in the curl correction apparatus 500 of the first embodiment, for example, gear teeth can be formed on the peripheral surface of the support member 512 and used as the outer peripheral gear. In this case, the first drive source is connected to the peripheral surface of the support member 512. According to this configuration, the first drive source can directly transmit power to the support member 512. Therefore, the support member 512 is rotated by the operation of the first drive source, and the curl correction direction is preferably changed.

The sheet is not limited to paper, and may be a film sheet, for example.
The present invention is not limited to the copying machine 1 and can be applied to an image forming apparatus such as a printer, a facsimile, or a complex machine thereof. The present invention can also be applied to apparatuses other than the image forming apparatus.

  DESCRIPTION OF SYMBOLS 1 ... Copy machine, 85 ... Curl correction roller pair, 85a ... Soft roller (1st roller), 85b ... Hard roller (2nd roller), 85c ... Nip part, 85d ... Start edge, 85e ... End edge, 500 ... Curl straightening device 510 ... Curl straightening unit 511 ... third rotation shaft 512 ... support member 514 ... peripheral gear 515 ... intermediate gear (input gear) 520 ... fixing member 530 ... roller drive motor (second drive) Source), 540 ... Unit drive motor (first drive source), 551 ... First rotation shaft, 552 ... First gear, 553 ... Two-stage gear (relay gear), 553a ... Third gear, 553b ... Second gear 561, second rotation shaft, 570, sheet introduction guide path (sheet introduction guide path), 580, sheet delivery guide path (sheet delivery guide path), 600, single drive motor, H, first surface, T, etc. Paper Door), V ... the second surface

Claims (4)

A sheet curl correction device for correcting sheet curl by passing a sheet between a first roller and a second roller,
A first roller that rotates about a first rotation axis and is elastically deformable;
A second roller that rotates about a second rotation axis that is parallel to the axial direction of the first rotation axis and that is formed to be harder than the first roller;
A support member for supporting the first roller and the second roller;
A first drive source for rotating the support member around a third rotation axis;
A first gear connected to an end of the second roller on the first drive source side;
A relay gear meshing with the first gear;
An input gear meshing with the relay gear and rotating about the third rotation shaft;
A second drive source for transmitting rotational force to the input gear;
An outer peripheral gear that rotates around the third rotation axis and has a peripheral surface on which gear teeth are formed;
The second roller is pressed against the first roller so as to bite the first roller so as to form a curved nip portion through which the sheet passes between the second roller and the first roller.
The third rotating shaft extends parallel to the axial direction of the first rotating shaft on a surface including the first rotating shaft and the second rotating shaft,
The outer peripheral gear is connected so as not to rotate relative to the support member;
The first drive source is connected to the outer peripheral gear, and is a sheet curl correction device capable of rotating the support member by 180 ° about the third rotation shaft. The curl correction unit includes the first roller, the second roller, and the support member, and the curl correction direction by the first roller and the second roller can be changed by rotating the support member. And
The first drive source and the second drive source are provided on a fixing member on the apparatus main body side that rotatably supports the curl correction unit, and the first rotation of the first roller in the curl correction unit. Arranged on one end side of the second rotating shaft of the shaft and the second roller;
2. The sheet curl correction apparatus according to claim 1, wherein each of the first drive source and the second drive source includes a single drive motor capable of switching a rotation direction to a normal rotation direction or a reverse rotation direction. The curl correction unit includes a sheet introduction guide path that guides introduction of a sheet into a nip portion between the first roller and the second roller, and a nip portion between the first roller and the second roller. A sheet derivation guide path for guiding the derivation of the seat from
The sheet curl correction apparatus according to claim 2, wherein the sheet introduction guide path and the sheet lead-out guide path are configured to rotate as the support member of the curl correction unit rotates. An image forming unit for forming an image on a sheet;
An image forming apparatus comprising: the sheet curl correcting apparatus according to claim 1, which corrects curl of the sheet on which an image is formed by the image forming unit.

Images