JP2011111316A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain, in an image forming apparatus configured to form an image on both sides of a transfer material, simplification of the apparatus and reduction in cost of the apparatus by sharing a position regulating member for regulating the position in the width direction of the transfer material. <P>SOLUTION: The image forming apparatus includes an image forming unit GK which is disposed on the upper side in vertical direction of a housing unit 52 which houses a transfer material T to form image on the transfer material T; a sheet conveyance path 521 having a horizontal conveyance section 528A which is formed between the housing unit 52 and the image forming unit GK so as to cross a casing from one side to the other side in horizontal direction thereof; a reversion unit which reverses both sides of the transfer material T; a recycle conveyance path which is joined to the upstream side in carrying direction D1 of the horizontal conveyance portion 528A; and the position regulating member 620 which is disposed at the horizontal conveyance portion 528A to regulates the position of paper T in width the direction thereof that is orthogonal to the carrying direction D1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  2. Description of the Related Art Conventionally, as an apparatus for forming (printing) an image on a sheet as a transfer material, an image forming apparatus such as a copier, a printer, a facsimile, or a complex machine of these is known. These image forming apparatuses include a storage unit that stores paper, a carry-out unit that carries out the paper stored in the storage unit, and an image forming unit that forms an image on the paper.

  In these image forming apparatuses, the position in the width direction of the sheet carried out of the storage unit may be shifted due to distortion of the storage unit, an assembly error, or the like. As a result, there is a problem that an image may not be formed at an appropriate position on the sheet by the image forming unit.

  Here, there is provided an image forming apparatus including a positioning device having a position restricting member that restricts a position in the width direction of the paper stored in the storage unit in order to eliminate a positional shift between the image formed on the paper and the paper. It has been proposed (see, for example, Patent Document 1).

By the way, an image forming apparatus that forms images on both sides of a sheet is known (for example, see Patent Document 2). An image forming apparatus described in Patent Document 2 includes an image forming unit that forms an image on a sheet, a reversing unit that reverses the sheet transported from the image forming unit, and a sheet that has been reversed by the reversing unit. And a return conveyance path that conveys toward the forming unit.
The image forming apparatus described in Patent Document 2 incorporates a positioning device having a position regulating member that regulates the position in the width direction of the sheet in order to prevent the position in the width direction of the sheet from shifting due to the reversing operation in the reversing unit. ing.

JP 9-314940 A JP 2006-206195 A

A general image forming apparatus includes a positioning device that suppresses a shift in the position in the width direction of a sheet transported from a storage unit, like the image forming apparatus described in Patent Document 1. In addition, an image forming apparatus that forms images on both sides of a sheet includes a positioning device that adjusts the position in the width direction of the sheet whose front and back are reversed by a reversing unit, as in the image forming apparatus described in Japanese Patent Application Laid-Open No. 2005-228867. In addition, a general image forming apparatus that forms images on both sides of a sheet needs to include both positioning devices described in Patent Document 1 and Patent Document 2.
However, when the image forming apparatus includes a plurality of positioning devices, the size of the device increases and the cost of the device increases.

  In the image forming apparatus that forms images on both surfaces of the transfer material, the present invention can simplify the apparatus by using a common position restriction member that restricts the position of the transfer material in the width direction. An object of the present invention is to provide an image forming apparatus capable of reducing the cost of the apparatus.

  The present invention includes a housing, a storage unit that stores a sheet-shaped transfer material, an image forming unit that is disposed on the upper side in the vertical direction of the storage unit and forms an image on the transfer material, and the storage unit. A sheet conveyance path for conveying the transferred material to be transferred to the image forming unit, and crossing from one side to the other side in the horizontal direction of the casing between the storage unit and the image forming unit. A sheet conveyance path having a horizontal conveyance unit formed as described above, a reversing unit that reverses the transfer material unloaded from the image forming unit, and the transfer material reversed by the reversing unit. A recycle conveyance path, a recycle conveyance path that joins upstream in the conveyance direction of the horizontal conveyance section, and a width direction that is disposed in the horizontal conveyance section and is perpendicular to the conveyance direction of the transfer material Oh A position regulating member for regulating the that position, an image forming apparatus including the.

  The sheet conveyance path includes a curved conveyance unit formed continuously downstream in the conveyance direction of the horizontal conveyance unit, and the horizontal conveyance unit and the curved conveyance unit are carried into the image forming unit. It is preferable that the horizontal transfer unit functions as a standby unit that waits for the material to be transferred before waiting, and can wait without substantially bending or bending one or a plurality of the materials to be transferred. .

  A regulating member driving unit configured to move the position regulating member in the width direction; and a regulating member driving control unit configured to control the regulating member driving unit so that the position in the width direction of the transfer material is positioned at a predetermined position; Are preferably provided.

  One or more roller pairs that are disposed near the position regulating member in the horizontal conveyance unit and sandwich and convey the material to be transferred, and one or more roller drives the one or more roller pairs to rotate. Based on a detection result from the rotation driving unit, the one or more detection members arranged along the horizontal conveying unit, and the one or more detection members, the transfer material is moved to the position regulating member and the width direction. When the carry-in detection unit detects that the transfer target material is lined up in the width direction with the position regulating member, rotation of the one or the plurality of roller pairs is performed. A rotation drive control unit that controls the rotation drive unit to stop the rotation drive unit, and the restriction member drive control unit is configured to stop the rotation of the one or the plurality of roller pairs by the rotation drive control unit. Is controlled If, it is preferable that the position regulating member for controlling the regulating member driving unit so as to position at a predetermined position of the transfer material in the width direction.

  According to the present invention, in an image forming apparatus that forms images on both sides of a transfer material, the apparatus can be simplified by using a common position regulating member that regulates the position of the transfer material in the width direction. In addition, an image forming apparatus capable of reducing the cost of the apparatus can be provided.

It is a figure for demonstrating arrangement | positioning of each component of the color copier 1 of one Embodiment of this invention. 1 is a diagram for explaining main components of a color copier 1 according to an embodiment of the present invention. 2 is a plan view showing a positioning device 610 in the color copying machine 1. FIG. It is a functional block diagram which shows the function of the color copier 1 of one Embodiment of this invention. 3 is a flowchart for explaining the operation of the color copier 1. 3 is a flowchart for explaining the operation of the color copier 1.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the overall structure of the color copier 1 as an image forming apparatus according to the present embodiment will be described with reference to FIGS. FIG. 1 is a diagram for explaining the arrangement of components of a color copier 1 according to an embodiment of the present invention. FIG. 2 is a diagram for explaining main components of the color copier 1 according to the embodiment of the present invention.

As shown in FIGS. 1 and 2, a color copying machine 1 as an image forming apparatus is arranged on the upper side in the vertical direction Z in the color copying machine 1 and feeds a predetermined document, and a document feeding unit 70. An image reading unit 71 that reads an image formed on the original document sent out by the printer, and a toner image on a sheet T as a sheet-shaped transfer material (sheet) based on image information from the image reading unit 71 that is arranged on the lower side. An apparatus main body M.
In the description of the color copier 1 of the present embodiment, the rotation axis direction of various rotating bodies (rollers, belts, etc.) in the photosensitive drums 2a to 2d, the fixing unit 9 and the like is referred to as “Y direction” (direction passing through FIG. ). The Y direction is also a direction orthogonal to the transport direction D1 of the paper T as a transfer material (see FIG. 2). The direction that is horizontal and orthogonal to the Y direction is referred to as the “X direction”. The vertical direction Z of the copier 1 is orthogonal to the X direction and the Y direction.

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 unit 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 is disposed on the upper side in the vertical direction of a paper feed cassette 52 as a storage unit to be described later. 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 laser scanner units 4a, 4b, and 4c as exposure units. 4d, developing devices 16a, 16b, 16c, 16d, toner cartridges 5a, 5b, 5c, 5d, toner supply units 6a, 6b, 6c, 6d, drum cleaning units 11a, 11b, 11c, 11d, The neutralization unit 90a, 90b, 90c, 90d, the intermediate transfer belt 7, the primary transfer rollers 37a, 37b, 37c, 37d, the intermediate transfer unit 200 as a transfer unit including the secondary transfer roller 8, and the fixing unit 9 And comprising.

  As shown in FIG. 1, the paper supply / discharge unit KH includes a paper feed cassette 52 as a storage unit, a manual paper feed unit 64, a paper T conveyance path 54, a registration roller pair 80, and a paper discharge unit 50. Is provided. As will be described later, the transport path 54 includes a seventh transport path 56, an eighth transport path 509, a discharge transport path 510, a reverse transport path 520 as a third transport path, and a fourth transport path 55. And a reverse discharge conveyance path 530 and a sheet conveyance path 521 as a sheet conveyance path.

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, Exposure by 4b, 4c, 4d, development by developing units 16a, 16b, 16c, 16d, primary transfer by intermediate transfer belt 7 and primary transfer rollers 37a, 37b, 37c, 37d, static eliminators 90a, 90b, 90c, 90d Is eliminated, and cleaning is performed by the drum cleaning units 11a, 11b, 11c, and 11d.
In the image forming unit GK, secondary transfer by the intermediate transfer belt 7, the secondary transfer roller 8 and the counter roller 108, 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 the image information related to the image read by the image reading unit 71. 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 developing rollers 116a, 116b, 116c, and 116d that are opposed to the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, a stirring roller for stirring the toner, and the like. Composed.

  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 arranged so as to be stretched between the driving roller 35 and the tension roller 36. Since the tension roller 36 is biased to the side away from the drive roller 35 by the spring 38, 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. In this way, primary transfer nips N1a, N1b, N1c, and N1d are formed, and the toner images of the respective colors developed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially primary-transferred to the intermediate transfer belt 7 sequentially. . 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 90a, 90b, 90c, and 90d are disposed 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. Here, the abutting or separating operation of the secondary transfer roller 8 is performed by rotating the entire intermediate transfer unit 200.

  The secondary transfer roller 8 is included in the intermediate transfer unit 200. The intermediate transfer unit 200 accommodates the secondary transfer roller 8 and rotatably supports the secondary transfer roller 8, a rotation drive gear 210 disposed on the side surface of the housing 201, and the secondary transfer roller 8, a roller side gear 220 disposed on the side surface of the housing 201 and an idle gear 230 disposed in contact with the rotation drive gear 210 and the roller side gear 220. The intermediate transfer unit 200 has a position at which the secondary transfer roller 8 can contact the intermediate transfer belt 7 around a rotation shaft (not shown) by a transfer unit moving unit (not shown) and a position where the intermediate transfer belt 7 does not contact the intermediate transfer belt 7 And is rotated.

  A counter roller 108 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 108. 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 formed on one surface (first surface) or the other surface (second surface) opposite to the one surface of the paper T. Secondary transferred.

  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

  A belt cleaning device 40 for cleaning the intermediate transfer belt 7 is disposed between the secondary transfer roller 8 and the tension roller 36. The belt cleaning device 40 includes a cleaning brush 41 that is in sliding contact with the surface of the intermediate transfer belt 7, a cleaning roller 42 that is disposed so as to be in contact with the cleaning brush 41, and a tip that is in contact with the surface of the cleaning roller 42. The blade 43 is disposed, and the recovery spiral 44 is disposed below the blade 43.

Next, the paper supply / discharge unit KH will be described.
As shown in FIGS. 1 and 2, on the lower side of the apparatus main body M, a paper feed cassette 52 that stores paper T is disposed. The paper feed cassette 52 includes a first paper feed cassette 52A, a second paper feed cassette 52B, and a third paper feed cassette 52C.
The first paper feed cassette 52A and the second paper feed cassette 52B are arranged side by side in the X direction. Specifically, the first paper feed cassette 52A is disposed on the switchback portion 560 side described later in the X direction of the case body BD. The second paper feed cassette 52B is disposed on the opposite side of the case body BD from the switchback portion 560 in the X direction. The first paper feed cassette 52A and the second paper feed cassette 52B have a storage space in which A4 size paper T can be arranged (A4 horizontal arrangement) so that the short side is along the X direction. The first paper feed cassette 52A and the second paper feed cassette 52B are large-capacity types having a large number of sheets T that can be accommodated.

  The third paper feed cassette 52C is arranged below the first paper feed cassette 52A and the second paper feed cassette 52B. The third paper feed cassette 52C is formed long in the X direction of the case body BD so as to straddle the first paper feed cassette 52A and the second paper feed cassette 52B. The third paper feed cassette 52C has a storage space in which A3 size paper T can be arranged (A3 vertical arrangement) so that the long side is along the X direction.

  The first paper feed cassette 52A, the second paper feed cassette 52B, and the third paper feed cassette 52C are arranged so that they can be pulled out from the case body BD of the apparatus main body M in the horizontal direction. In the first paper feed cassette 52A, the second paper feed cassette 52B, and the third paper feed cassette 52C, sheets T are stored in a stacked state. The first paper feed cassette 52A and the second paper feed cassette 52B include paper containers 601A and 601B for storing paper T, and placement plates 60A and 60B on which the paper T is placed in a stacked state. The placement plates 60A and 60B arranged in the first paper feed cassette 52A and the second paper feed cassette 52B are arranged in parallel in the horizontal direction. A placement plate 60C on which the paper T is placed is disposed in the third paper feed cassette 52C.

  The placement plates 60A and 60B arranged in the first paper feed cassette 52A and the second paper feed cassette 52B are arranged movably in the vertical direction (vertical direction) inside the paper containers 601A and 601B, respectively. The mounting plates 60A and 60B are moved upward (vertical direction) by driving a moving motor (not shown). Further, when the paper T is placed on each of the placement plates 60A and 60B, the placement plates 60A and 60B move downward in the vertical direction due to the weight of the placement plates 60A and 60B (and the paper T). Is done. Each of the mounting plates 60A and 60B is moved while being guided in a vertical direction by a lifting guide (not shown).

  The paper T placed on the placement plates 60A, 60B, and 60C is disposed at the feeding side end of the paper T of each of the first paper feed cassette 52A, the second paper feed cassette 52B, and the third paper feed cassette 52C. The first cassette sheet feeding unit 51A serving as the unloading unit, the second cassette sheet feeding unit 51B serving as the unloading unit, and the third cassette sheet feeding unit 51C serving as the unloading unit are sent to the conveyance path 54.

  In the present embodiment, each of the first cassette paper feed unit 51A, the second cassette paper feed unit 51B, and the third cassette paper feed unit 51C is arranged on the end side on the switchback unit 560 side in the X direction in the case body BD. Is done.

  Each of the first cassette paper feed unit 51A, the second cassette paper feed unit 51B, and the third cassette paper feed unit 51C has a forward feed roller 61A, 61B for taking out the paper T on the placement plates 60A, 60B, 60C. , 61C and a pair of paper feed rollers 63A, 63B, 63C for feeding the paper T to the transport path 54 one by one.

  The first cassette sheet feeding unit 51A, the second cassette sheet feeding unit 51B, and the third cassette sheet feeding unit 51C are respectively stored in the first sheet feeding cassette 52A, the second sheet feeding cassette 52B, and the third sheet feeding cassette 52C. The discharged paper T is carried out to a paper feed conveyance path 521 described later.

A transport path 54 for transporting the paper T is formed between the first cassette paper feed unit 51A, the second cassette paper feed unit 51B, and the third cassette paper feed unit 51C and the paper discharge unit 50. The conveyance path 54 includes a sheet feeding conveyance path 521, a seventh conveyance path 56 from the secondary transfer nip N <b> 2 (image forming unit GK) to the fixing unit 9, and an eighth conveyance from the fixing unit 9 to the first branching unit 501. A reversal conveyance path (third conveyance path) connected to a path 509, a discharge conveyance path 510 from the first branching section 501 to the paper discharge section 50, and a switchback section 560 as a reversing section from the first branching section 501. 520 and a fourth conveyance path 55 from the switchback unit 560 to the secondary transfer nip N2 (image forming unit GK).
In the description of this embodiment, the transport direction of the paper T is referred to as “transport direction D1”. Further, the width direction that is orthogonal to the transport direction of the paper T is referred to as a “transport width direction D2”.

The paper feed conveyance path 521 conveys the paper T carried out from the first paper feed cassette 52A, the second paper feed cassette 52B, or the third paper feed cassette 52C to the image forming unit GK.
The paper feed transport path 521 is in the fifth transport path 522 that connects the first paper feed cassette 52A, the second paper feed cassette 52B, or the third paper feed cassette 52C and the first junction 511, and the fourth transport path 55. This is a conveyance path constituted by a portion from the first joining portion 511 to the secondary transfer nip N2 (image forming portion GK). The paper feed path 521 is secondary from the first paper feed cassette 52A, the second paper feed cassette 52B, or the third paper feed cassette 52C in the paper T stored in the first paper feed cassette 52A or the third paper feed cassette 52C. Used as a transport path to the transfer nip N2 (image forming unit GK).

  The first junction 511 is formed on the upstream side in the transport direction D <b> 1 of the paper T in the paper feed transport path 521. The first joining unit 511 is formed on the upstream side in the transport direction D1 from the intermediate position between the switchback unit 560 and the image forming unit GK in the paper feed transport path 521. The first merging portion 511 is formed on the end side on the switchback portion 560 side in the X direction in the paper feed conveyance path 521. A recycling transport path 523 described later is connected to the first junction 511.

  The fifth transport path 522 is a transport path from the first paper feed cassette 52A to the first merge section 511, a transport path from the second paper feed cassette 52B to the first merge section 511, or a third transport path from the third paper feed cassette 52C. It is used as a conveyance path to the 1st junction 511. The fifth conveyance path 522 includes a first carry-in path 522A that connects the first paper feed cassette 52A and the first merge section 511, and a second carry-in path 522B that couples the second paper feed cassette 52B and the first merge section 511. And a third carry-in path 522C that connects the third paper feed cassette 52C and the first junction 511.

A portion from the first joining unit 511 to the secondary transfer nip N2 (image forming unit GK) in the sheet feeding conveyance path 521 includes a horizontal conveyance unit 528A and a curved conveyance unit 528B.
The horizontal conveyance unit 528A is provided between the first sheet feeding cassette 52A, the second sheet feeding cassette 52B, the third sheet feeding cassette 52C, and the image forming unit GK from one side in the horizontal direction (X direction) of the case body BD. The case body BD is formed across the other side.
The curved conveyance unit 528B is continuously formed on the downstream side in the conveyance direction of the horizontal conveyance unit 528A.

  A portion from the first joining portion 511 to the secondary transfer nip N2 (image forming portion GK) in the paper feed conveyance path 521 is configured as a standby portion 528 that waits for the paper T. The standby unit 528 makes the paper T carried out from the first paper feed cassette 52A, the second paper feed cassette 52B, or the third paper feed cassette 52C stand by. The paper T waiting on the standby unit 528 is the paper T before being carried into the image forming unit GK.

  The standby unit 528 includes a flat standby unit configured by the horizontal conveyance unit 528A and a curved standby unit configured by the curved conveyance unit 528B. The flat standby unit (horizontal conveyance unit) 528A is formed on the first joining unit 511 side in the standby unit 528. The flat standby portion 528A is a conveyance path formed in a substantially flat surface in a portion (standby portion) 528 from the first joining portion 511 to the secondary transfer nip N2 (image forming portion GK) in the paper feed conveyance path 521.

  Specifically, the flat standby unit 528A includes the first paper feed cassette 52A, the second paper feed cassette 52B, and the second paper feed cassette 52B, above the first paper feed cassette 52A, the second paper feed cassette 52B, and the third paper feed cassette 52C. The case body BD is formed in a planar shape extending long in the horizontal direction (X direction) across the third paper feed cassette 52C. The flat standby unit 528A can make the paper T stand by without being substantially bent or bent.

  The curved standby unit (curved conveyance unit) 528B is formed on the image forming unit GK side in the standby unit 528. The curved standby portion 528B is formed continuously with the flat standby portion 528A. The curved standby section 528B is arranged on the switchback section 560 side of the flat standby section 528A in the portion (standby section) 528 from the first joining section 511 to the secondary transfer nip N2 (image forming section GK) in the paper feed conveyance path 521. Is a transport path formed from the opposite end to the secondary transfer nip N2 (image forming unit GK).

  The curved standby part 528B is a conveyance path formed so as to extend upward from the flat standby part 528A and to be curved. Specifically, the curved standby part 528B is connected to the flat standby part 528A at the end of the case body BD opposite to the switchback part 560 side in the X direction. The curved standby portion 528B is formed and curved so as to extend upward from the case body BD from the end of the flat standby portion 528A to the secondary transfer nip N2 (image forming portion GK).

  As shown in FIG. 2, a guide plate and a plurality of roller pairs that convey the paper T while guiding the paper T are arranged in the paper feed conveyance path 521. A plurality of intermediate roller pairs 550 as a roller pair, a registration roller pair 80, and a paper T are detected in the paper feed conveyance path 521 between the paper feed roller pairs 63A, 63B, 63C and the image forming unit GK. For this purpose, a plurality of first sensors S are arranged.

  The paper feed roller pairs 63A, 63B, and 63C are roller pairs for sending the paper T one by one to the paper feed conveyance path 521 as described above. The paper feed roller pairs 63A, 63B, and 63C are controlled by a carry-out control unit 105, which will be described later, and send the paper T to the paper feed conveyance path 521.

  The registration roller pair 80 is disposed on the upstream side (right side in FIG. 1) in the transport direction D1 of the paper T in the secondary transfer nip N2 (image forming unit GK). In a stopped state, the registration roller pair 80 is rotated once after the leading end portions of the paper T fed from the paper feeding roller pairs 63A, 63B, and 63C are brought into contact with the downstream side in the transport direction D1. It is a pair of rollers to send out. Further, the registration roller pair 80 is a roller pair for correcting skew (oblique feeding) of the paper T and for forming a toner image and adjusting the timing in the image forming unit GK. When the registration roller pair 80 stops, the paper T is waited by the curving standby unit 528B. The registration roller pair 80 is rotationally driven by a registration roller driving unit (not shown).

  The plurality of intermediate roller pairs 550 are spaced apart from each other by a predetermined interval in the paper feed conveyance path 521. The plurality of intermediate roller pairs 550 cause the standby unit 528 to wait for the paper T, or sandwich the paper T and convey it toward the secondary transfer nip N2 (image forming unit GK).

  In the present embodiment, the plurality of intermediate roller pairs 550 are, for example, the first roller pair 551, the second roller pair 552, and the third roller pair as the roller pair from the first joining portion 511 side in the flat standby portion 528A. 553 and a fourth roller pair 554 as a roller pair. Each of the first roller pair 551, the second roller pair 552, the third roller pair 553, and the fourth roller pair 554 is disposed at a predetermined interval in the plane standby portion 528A in order to sandwich and convey the paper T. The

  To the plurality of intermediate roller pairs 550, one or a plurality of rotation driving units 650 that rotationally drive the plurality of intermediate roller pairs 550 are connected. The plurality of intermediate roller pairs 550 causes the standby unit 528 to wait while the rotation driving unit 650 is driven, or sandwiches the paper T and conveys it toward the secondary transfer nip N2 (image forming unit GK).

  In the present embodiment, the first roller pair 551, the second roller pair 552, the third roller pair 553, and the fourth roller pair 554 include a first rotation driving unit 651, a second rotation driving unit 652, and a third rotation, respectively. Each of the drive unit 653 and the fourth rotation drive unit 654 is connected. The first rotation driving unit 651, the second rotation driving unit 652, the third rotation driving unit 653, and the fourth rotation driving unit 654 respectively include a first roller pair 551, a second roller pair 552, a third roller pair 553, and a fourth rotation driving unit 654. Each of the roller pair 554 is rotationally driven or the rotational driving is stopped. Thus, the paper T is sequentially sandwiched between the first roller pair 551, the second roller pair 552, the third roller pair 553, and the fourth roller pair 554, and is guided and transported to the paper feed transport path 521.

  The plurality of first sensors S are arranged immediately before each of the plurality of intermediate roller pairs 550 in the conveyance direction D1 of the paper T (upstream side in the conveyance direction D1) and immediately before the registration roller pair 80 (upstream side in the conveyance direction D1). The Each of the plurality of intermediate roller pairs 550 causes the standby unit 528 to wait for the paper T or conveys the paper T toward the image forming unit GK based on detection signal information from each of the plurality of first sensors S. Further, 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.

  A positioning device 610 that regulates the position in the transport width direction D2, which is a direction orthogonal to the transport direction D1 of the paper T, is disposed in the horizontal transport unit 528A in the paper feed transport path 521. Specifically, the positioning device 610 is disposed on the downstream side in the transport direction D1 in the horizontal transport unit 528A. Specifically, the positioning device 610 is disposed in the vicinity of the third roller pair 553 and the fourth roller pair 554 between the third roller pair 553 and the fourth roller pair 554 in the horizontal conveyance unit 528A.

The positioning device 610 adjusts (positions) the position in the transport width direction D2 orthogonal to the transport direction D1 with respect to the paper T transported through the horizontal transport unit 528A.
The configuration and operation of the positioning device 610 will be described in detail later.

  The seventh conveyance path 56 is a conveyance path that conveys the paper T on which the toner image is transferred by the intermediate transfer unit 200 from the secondary transfer nip N2 (image forming unit GK) to the fixing unit 9. A conveyance belt 156 that conveys the paper T in a state where the paper T is placed is disposed in the seventh conveyance path 56.

  The eighth transport path 509 is a transport path for transporting the paper T on which the toner image is fixed by the fixing unit 9 toward the first branching unit 501.

  The first branch portion 501 is a branch portion formed on the downstream side in the transport direction in which the paper T is transported in the eighth transport path 509. The first branching unit 501 connects the eighth transport path 509, the discharge transport path 510, and the reverse transport path 520.

  A first switching member 540 is provided in the first branch portion 501. The first switching member 540 selects the transport direction D1 of the paper T transported from the eighth transport path 509 in the direction toward the discharge transport path 510 or the direction toward the reversal transport path 520 for reversing the paper T. Switch. The first switching member 540 is moved by a drive unit (not shown).

  The discharge conveyance path 510 is a conveyance path branched from the eighth conveyance path 509 via the first branch portion 501. The discharge conveyance path 510 is a conveyance path that conveys the paper T discharged from the fixing unit 9 toward the outside of the case body BD via the paper discharge unit 50.

  The reversing conveyance path 520 is a conveyance path different from the discharge conveyance path 510 branched from the eighth conveyance path 509 via the first branching unit 501. The reversing conveyance path 520 is a conveyance path from the first branching unit 501 to a switchback unit 560 described later. The reversing conveyance path 520 extends from the first branch portion 501 substantially downward of the case body BD. The reverse conveyance path 520 conveys the paper T on which the toner image is formed on the first surface by the image forming unit GK from the first branching unit 501 to the switchback unit 560.

  The switchback portion 560 is disposed near one end portion in the X direction of the case body BD. The switchback unit 560 includes a switchback roller pair 561 and a switchback rotation drive unit (not shown).

  The switchback roller pair 561 reverses the front and back of the paper T that is unloaded from the image forming unit GK and conveyed to the reversing conveyance path 520. The switchback rotation driving unit rotates the switchback roller pair 561 in a direction opposite to the direction in which the paper T is pulled in or the direction in which the paper T is pulled in. Thereby, the switchback roller pair 561 switches the transport direction of the drawn paper T to the opposite direction.

  Further, the switchback rotation driving unit temporarily stops the rotation of the switchback roller pair 561 that has pulled the paper T when the rotation direction of the switchback roller pair 561 is switched to the opposite direction. As a result, the switchback unit 560 switches the transport direction of the drawn paper T to the opposite direction and reverses the front and back of the paper T. Then, the switchback unit 560 sends the paper T to the fourth transport path 55 from the same side as the side where the paper T is pulled in the switchback unit 560.

The fourth transport path 55 includes a recycle transport path 523 and a portion of the paper feed transport path 521 from the first joining unit 511 to the image forming unit GK. A portion from the first joining unit 511 to the image forming unit GK in the sheet feeding conveyance path 521 includes a horizontal conveyance unit 528A and a curved conveyance unit 528B.
The recycle conveyance path 523 merges the paper T, which is turned upside down by the switchback unit 560, with the first merge unit 511 formed on the upstream side in the conveyance direction D1 of the horizontal conveyance unit 528A in the paper feed conveyance path 521.
The fourth transport path 55 is connected to the upstream side in the transport direction D1 of the horizontal transport unit 528A by the recycle transport path 523, and the horizontal transport unit 528A and the curved transport unit 528B in the paper feed transport path 521 are common.
The fourth conveyance path 55 is a conveyance path that conveys the paper T, whose front and back are reversed by the switchback unit 560, toward the secondary transfer nip N2 (image forming unit GK). The fourth transport path 55 joins the paper T whose front and back are reversed by the switchback unit 560 to the paper feed transport path 521 via the recycle transport path 523 and returns it to the upstream side of the image forming unit GK. Configured as a road.

  In the present embodiment, the fourth transport path (return transport path) 55 passes from the switchback unit 560 to the paper feed transport path 521 through the first branch unit 501, the eighth transport path 509, and the fixing unit 9. Merge and pass substantially horizontally below the seventh conveyance path 56, the secondary transfer roller 8 and the registration roller pair 80, and at the end of the case body BD opposite to the switchback portion 560 side in the X direction, It is formed so as to curve toward. The fourth conveyance path 55 is a conveyance path used in the case of performing so-called double-sided printing in which toner images are printed on both sides of the paper T. For example, the sheet T is returned to the image forming unit GK via the return conveyance path (fourth conveyance path) 55 in a state where the front and back sides are reversed by the switchback unit 560.

  Specifically, when a toner image is printed on the first surface of the paper T, the paper T is transferred to the intermediate transfer unit 200 (image forming unit GK) so that the first surface faces the surface of the intermediate transfer belt 7. Be transported. When a toner image is printed on the second surface of the paper T printed on the first surface of the paper T, the paper T is returned to the return transport path (fourth transport) with the front and back reversed by the switchback unit 560. Path) 55 and returned to the intermediate transfer unit 200 (image forming unit GK). As a result, the sheet is conveyed to the intermediate transfer unit 200 (image forming unit GK) so that the second surface faces the surface of the intermediate transfer belt 7.

  A manual paper feed section 64 is provided on the right side surface of the apparatus main body M in FIG. The manual paper feed unit 64 includes a manual feed tray 65 that forms a side wall in the closed state, and a paper feed roller 66. The manual feed tray 65 is attached at its lower end to the vicinity of the upper side of the curved standby section 528B in the paper feed conveyance path 521 so as to be rotatable (openable and closable). The manual paper feed unit 64 feeds the paper T placed on the open manual feed tray 65 to the curved standby unit 528B of the paper feed conveyance path 521.

  The reverse discharge transport path 530 is a transport path that connects the second branching section 502 and the paper discharge section 50 formed on the upstream side in the transport direction D1 with respect to the first joining section 511 in the fourth transport path 55. The reverse discharge transport path 530 is a transport path that reverses the paper T on which the image is formed on the first surface and the second surface and transports the paper T to the paper discharge unit 50.

  The second branch portion 502 is formed on the upstream side in the transport direction D1 with respect to the first joining portion 511 in the fourth transport path 55. The second branch member 502 is provided with a second switching member 541. The second switching member 541 is configured to change the transport destination of the paper T, which is transported by reversing the front and back of the paper T in the switchback unit 560, to the direction toward the reverse discharge transport path 530 or the fourth transport path (return transport path) 55. Selectively switch in the direction you head. The second switching member 541 is moved by a drive unit (not shown).

  A third branch portion 503 is formed on the reverse discharge transport path 530 on the paper discharge portion 50 side of the second branch portion 502. The third branch portion 503 is provided with a third switching member (not shown). The third switching member prohibits the conveyance of the paper T discharged from the switchback unit 560 to the reverse conveyance path 520 and permits the conveyance to the reverse discharge conveyance path 530 side. The third switching member is moved by a drive unit (not shown).

Next, the positioning device 610 will be described with reference to FIG. FIG. 3 is a plan view showing the positioning device 610 in the color copier 1.
As shown in FIG. 3, the positioning device 610 includes a mounting plate 615, a position restricting member 620, a rack and pinion mechanism 635, and a guide member driving unit 630 as a restricting member driving unit that moves the position restricting member 620. (See FIG. 3) and a second sensor 648 as a detection member. The position restricting member 620 includes a first guide member 620a and a second guide member 620b.

As shown in FIG. 3, the mounting plate 615 is a planar plate member. The mounting plate 615 has a flat mounting surface 615a. On the placement surface 615a, the paper T carried in from the predetermined transport direction D1 (arrow P direction) is placed.
On the placement surface 615a, the paper T carried in from the predetermined transport direction D1 (arrow P direction) is placed.

As shown in FIG. 3, the first guide member 620 a and the second guide member 620 b are disposed on the placement surface 615 a side of the placement plate 615.
Each of the first guide member 620a and the second guide member 620b rises in the vertical direction from the bottom surface portions 621a and 621b on which the paper T is placed and the outer edges of the bottom surface portions 621a and 621b in the transport width direction D2. And standing wall portions 622a and 622b that are in contact with the outer edge of the paper T.

  The first guide member 620a and the second guide member 620b move in a direction parallel to the placement surface 615a and closer to each other, and in a direction parallel to the placement surface 615a and away from each other. The first guide member 620a and the second guide member 620b are driven by the guide member driving unit 630. Specifically, the first guide member 620a is movable in the arrow Q3 direction approaching the second guide member 620b and the arrow Q4 direction moving away from the second guide member 620b. The second guide member 620b is movable in the arrow Q1 direction approaching the first guide member 620a and the arrow Q2 direction moving away from the first guide member 620a.

  The first guide member 620a and the second guide member 620b are movable to a standby position and a positioning position with reference to the home position (from a predetermined initial position). The first guide member 620a and the second guide member 620b located at the standby position move to the positioning position after the paper T is placed on the placement plate 615, and adjust the position of the paper T in the transport width direction D2. (Position).

The first guide member 620a and the second guide member 620b are configured so that the paper T is sandwiched between the standing wall portion 622a of the first guide member 620a and the standing wall portion 622b of the second guide member 620b, and the paper T is conveyed in the conveyance width direction. Adjust the position at D2.
The guide member driving unit 630 moves the first guide member 620a and the second guide member 620b in the transport width direction D2, and abuts against the outer edge of the paper T to perform positioning in the paper T transport width direction D2.

The rack and pinion mechanism 635 includes a pinion 636, and a rack 637a and a rack 637b that mesh with the pinion 636 and are arranged in parallel to each other.
A guide member driving unit 630 is connected to the pinion 636.

Each of the rack 637a and the rack 637b is connected to the first guide member 620a and the second guide member 620b on the outer side in the transport width direction D2.
Specifically, each of the rack 637a and the rack 637b is connected to the first guide member 620a and the second guide member 620b by a countersunk screw (not shown).

  Cylindrical rollers 627a and 627a are rotatably disposed between the rack 637a and the countersunk screw. Cylindrical rollers 627a and 627a are slidably fitted into a groove 628a formed on the mounting plate 615. Accordingly, the first guide member 620a is moved while being guided in the transport width direction D2 (arrows Q3 and Q4 directions).

Cylindrical rollers 627b and 627b are rotatably disposed between the rack 637b and the countersunk screw. Cylindrical rollers 627b and 627b are slidably fitted into a groove 628b formed in the mounting plate 615. Accordingly, the second guide member 620b is moved while being guided in the transport width direction D2 (arrows Q1 and Q2 directions).
According to the rack and pinion mechanism 635, the first guide member 620a and the second guide member 620b can be moved in the opposite directions by the same distance.

  As described above, the guide member driving unit 630 moves the first guide member 620a and the second guide member 620b in the transport width direction D2 and contacts the outer edge of the paper T to perform positioning in the paper T transport width direction D2. .

The second sensor 648 is disposed along the horizontal conveyance unit 528A.
The second sensor 648 detects that the paper T is placed on the placement plate 615 together with the carry-in detection unit 112 described later. The second sensor 648 detects that the paper T is carried into the positioning device 610 together with a carry-in detection unit 112 described later.

Next, functions related to control of the color copier 1 of the present embodiment will be described with reference to FIG. FIG. 4 is a functional block diagram showing functions of the color copier 1 according to the embodiment of the present invention.
As shown in FIG. 4, the color copier 1 includes a receiving unit 101, a plurality of first sensors S, a second sensor 648, a control unit 102, and a storage unit 150. The receiving unit 101 determines the number of pieces of paper T on which the image is to be formed, the type information about the type of the paper T, and whether to form an image on one side of the paper T or whether to form an image on both sides of the paper T. It is possible to receive image formation instruction information including printing surface information relating to this. The receiving unit 101 outputs the received image formation instruction information to the control unit 102 (standby status management unit 107).

The image formation instruction information includes the number information relating to the paper T received by the operation unit (not shown) of the color copying machine 1, the type information relating to the paper T, the printing surface information relating to the paper T, and a PC (personal computer). The number information about the paper T received from the external device, the type information about the paper T, and the printing surface information about the paper T are included.
The type information regarding the type of the paper T in the image formation instruction information includes the size standard (the length in the vertical direction and the length in the horizontal direction) regarding the type of the paper T and the transport direction (the vertical direction or the horizontal direction) of the paper T. Information).

The first sensor S is disposed immediately in front of each of the plurality of roller pairs 550 and the registration roller pair 80. When the paper T is transported to a position in front of each of the plurality of roller pairs 550 and the registration roller pair 80, a predetermined sensor S is provided. The signal is output to the control unit 102 (paper detection unit 104).
When the paper T is carried into the positioning device 610, the second sensor 648 outputs a predetermined signal to the control unit 102 (carry-in detection unit 112).

The control unit 102 includes a paper detection unit 104, a carry-out control unit 105, a rotation drive control unit 106, a standby state management unit 107, a guide member drive control unit 111, and a carry-in detection unit 112.
The paper detection unit 104 detects the presence / absence of the paper T at the detection positions of the plurality of first sensors S in the paper feed conveyance path 521 based on the detection signal information regarding the paper T from the plurality of first sensors S. The paper detection unit 104 outputs detection information related to the presence or absence of the paper T to the standby status management unit 107 described later.

  The rotation drive control unit 106 controls the rotation drive unit 650 so as to convey the paper T waiting on the standby unit 528 toward the image forming unit GK based on information from the standby state management unit 107 described later. Further, the rotation drive control unit 106 controls the rotation drive unit 650 so that the standby unit 528 waits for a certain number of sheets of paper T based on information from the standby state management unit 107 described later. In the present embodiment, the rotation driving unit 650 can cause the A4 horizontal sheet T to wait on the flat standby unit 528A in the standby unit 528. Further, the rotation driving unit 650 can make one plane A3 vertical paper T wait in the flat standby unit 528A in the standby unit 528.

  Further, the rotation drive control unit 106 rotates the third roller pair 553 and the fourth roller pair 554 when the carry-in detection unit 112 described later detects that the paper T is aligned with the position regulating member 620 in the width direction D2. The third rotation drive unit 653 and the fourth rotation drive unit 654 are controlled so as to stop the operation.

  The rotation drive control unit 106 drives the guide member when the third rotation drive unit 653 and the fourth rotation drive unit 654 are controlled so that the rotation of the third roller pair 553 and the fourth roller pair 554 is stopped. A predetermined signal is output to the control unit 111.

  Further, when the positioning device 610 finishes the positioning operation in the conveyance width direction D2 of the paper T, the rotation drive control unit 106 sets the third roller pair 553 and the fourth roller pair 554 in a rotatable state. The third rotation drive unit 653 and the fourth rotation drive unit 654 are controlled. Note that whether or not the positioning operation in the positioning device 610 has ended may be determined by detecting with a sensor (not shown) that detects the movement of the first guide member 520a or the second guide member 520b, or a carry-in detection unit. The determination may be made by measuring the time after the paper T is detected by 112.

  The carry-out control unit 105 controls the first cassette sheet feeding unit 51A, the second cassette sheet feeding unit 51B, and the third cassette sheet feeding unit 51C based on information from a standby status management unit 107 described later. The first cassette sheet feeding unit 51A, the second cassette sheet feeding unit 51B, and the third cassette sheet feeding unit 51C are controlled by a control signal from the carry-out control unit 105, so that the first sheet feeding cassette 52A, the second sheet feeding cassette 52B, 3 The paper T stored in the paper feed cassette 52C is carried out.

  The standby status management unit 107 is based on image formation instruction information including detection information regarding the paper T input by the paper detection unit 104, number information regarding the number of sheets T input by the reception unit 101, and type information regarding the paper T. The standby state of the paper T in the standby unit 528 is managed. The standby status management unit 107 outputs information on the standby status to the carry-out control unit 105 and the rotation drive control unit 106.

  Specifically, the standby status management unit 107 recognizes the standby status of the paper T waiting on the paper feed conveyance path 521 based on the detection information regarding the paper T input by the paper detection unit 104.

  In addition, the standby status management unit 107 receives the sheet T conveyed through the sheet feeding conveyance path 521 based on the image formation instruction information including the number information regarding the number of sheets T input by the receiving unit 101 and the type information regarding the sheet T. The total number and remaining number of sheets and the size of the paper T are recognized.

  The standby status management unit 107 also sets the standby status of the paper T, the total number of sheets T and the remaining number, the size of the paper T, the driving status of the rotation driving unit 650, the first cassette paper supply unit 51A, and the second cassette paper supply. The standby state of the paper T in the standby unit 528 is predicted based on the driving status of the unit 51B and the third cassette paper feeding unit 51C and the driving status of the guide member driving unit 630. For example, when the paper T on the registration roller pair 80 side in the standby unit 528 is conveyed to the image forming unit GK, the standby status management unit 107 transfers the next conveyed paper T to the registration roller pair 80 in the standby unit 528. Predict the waiting situation that will be sequentially pulled to the side. As described above, the standby state management unit 107 predicts the standby state of the paper T in the standby unit 528 and outputs information on the standby state to the carry-out control unit 105 and the rotation drive control unit 106.

  The guide member drive control unit 111 controls the guide member drive unit 630 to move each of the first guide member 620a and the second guide member 620b to the positioning position. The guide member drive control unit 111 controls the guide member drive unit 630 based on the size information of the paper T included in the information output from the receiving unit 101 and position information stored in the storage unit 150 described later. .

  Here, the guide member drive control unit 111 moves the first guide member 620a and the second guide member 620b to the standby position based on information on the standby position stored in the storage unit 150 described later. The drive unit 630 is controlled.

  Further, the guide member drive control unit 111 is configured such that when the third rotation drive unit 653 and the fourth rotation drive unit 654 are controlled such that the rotation of the third roller pair 553 and the fourth roller pair 554 is stopped, the guide member drive control unit 111 The drive control unit 111 drives the guide member to move the first guide member 620a and the second guide member 620b from the standby position to the positioning position after a predetermined time based on the positioning position information stored in the storage unit 150. The unit 630 is controlled.

  The carry-in detection unit 112 detects that the paper T is aligned with the position regulating member 620 in the width direction D <b> 2 based on the detection result output from the second sensor 648. The carry-in detection unit 112 outputs a predetermined signal to the rotation drive control unit 106 when detecting that the paper T is aligned with the position regulating member 620 in the width direction D2.

  Here, the storage unit 150 stores position information related to the positions of the first guide member 620a and the second guide member 620b set in advance for each size of the paper T. The position information includes information regarding the standby position and information regarding the positioning position. The standby position is a position where the first guide member 620a and the second guide member 620b wait for the paper T that is carried into the positioning device 610. The positioning position refers to the positions of the first guide member 620a and the second guide member 620b that can adjust the position of the paper T in the conveyance width direction D2 when the first guide member 620a and the second guide member 620b abut on the outer edge of the paper T. It is a position.

Next, the basic operation of the color copier 1 of this embodiment will be briefly described.
The image read from the document feeding unit 70 is read by the image reading unit 71. The image information in the read image is input to the apparatus main body M.

  In the apparatus main body M, the input image information is input to an image formation control unit (not shown). Based on the image information, the image formation control unit is a photosensitive drum 2a, 2b, 2c, 2d as an image carrier constituting the image formation unit GK, a charging unit 10a, 10b, 10c, 10d, a laser scanner unit 4a, 4b, 4c, 4d, developing devices 16a, 16b, 16c, 16d and the like are controlled. A predetermined toner image is formed on the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d based on the image information (see FIG. 1).

Specifically, in the image forming unit GK, charging by the charging units 10a, 10b, 10c, and 10d, laser scanner units 4a, 4b, and 4c in order from the upstream side to the downstream side with respect to the surface of the photosensitive drum 2. 4d exposure and development by the developing devices 16a, 16b, 16c and 16d are performed.
Specifically, first, the charging units 10a, 10b, 10c, and 10d uniformly charge the surface of the photosensitive drum 2 to negative (minus polarity) or positive (plus polarity).
Next, 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 the image information related to the image read by the image reading unit 71. 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.
Next, the developing devices 16a, 16b, 16c, and 16d attach the toner of each color to the electrostatic latent images formed on the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, and transfer the toner images to the photosensitive drum 2a. 2b, 2c, 2d.

  The toner images formed on the photosensitive drums 2a, 2b, 2c, and 2d are secondarily transferred to the first surface of the paper T at the secondary transfer nip N2 via the intermediate transfer belt 7. The paper T printed (image formed) on the first surface is discharged from the paper discharge unit 50 to the outside of the case body BD (see FIG. 1).

Here, when the paper T is printed on one side, the paper T on which the image is formed on the first side is directly discharged via the discharge conveyance path 510 (without passing through the reverse conveyance path 520). The paper 50 is discharged to the outside of the case body BD.
On the other hand, when the paper T is printed on both sides, the front and back of the paper T are reversed through the reversing conveyance path 520, the switchback roller pair 561, the return conveyance path (fourth conveyance path) 55, and the like. Then, it is conveyed again to the secondary transfer nip N2, and printing (image formation) on the second surface of the paper T is performed. Further, the paper T printed on the second surface is again turned upside down (without printing) through the reversing conveyance path 520, the switchback roller pair 561, the reversing discharge conveyance path 530, and the like. Inverted and discharged from the paper discharge unit 50 to the outside of the case body BD.

Next, specific operations in the color copier 1 of the present embodiment will be described with reference to FIGS. 1 to 5B. FIG. 5A is a flowchart for explaining the operation of the color copier 1. FIG. 5B is a flowchart for explaining the operation of the color copier 1.
The specific operation of the first example of the color copier 1 according to the present embodiment will be described in the case where an A4 size paper T is conveyed in the horizontal direction (A4 landscape paper T). Each of the first paper feed cassette 52A and the second paper feed cassette 52B stores a plurality of A4 size paper T. In the first paper feed cassette 52A and the second paper feed cassette 52B, the A4 size paper T is arranged (A4 horizontal arrangement) so that the short side is along the X direction.

  As shown in FIG. 5A, in step ST1, the color copier 1 is in an initial state in which no paper T is present in the transport path 54. The accepting unit 101 accepts image formation instruction information generated when, for example, an operating unit (not shown) arranged outside the copier 1 is operated in the initial state of the color copier 1.

  Specifically, in the image formation instruction information input from the operation unit, the number information regarding the number of sheets T on which the image is formed, the type information regarding the type of the sheet T, and the image on one side of the sheet T are formed. Or printing surface information relating to whether images are to be formed on both sides of the paper T. The receiving unit 101 outputs the received image formation instruction information to the standby state management unit 107.

  In step ST2, the guide member drive control unit 111 moves or maintains each of the first guide member 620a and the second guide member 620b to the standby position based on the standby position information stored in the storage unit 150. The guide member driving unit 630 is controlled.

  In step ST <b> 3, the carry-out control unit 105 controls the first cassette paper feed unit 51 </ b> A so that the paper T is carried out to the paper feed conveyance path 521 based on the number information of the paper T in the image formation instruction information. The sheets T are sequentially conveyed toward the image forming unit GK through the sheet feeding conveyance path 521.

  In step ST4, the paper T is transported toward the horizontal transport unit 528A in the paper feed transport path 521.

  In step ST <b> 5, the paper detection unit 104 detects the presence or absence of the paper T in the paper feed conveyance path 521 based on the detection signals of the paper T from the plurality of first sensors S. The paper detection unit 104 outputs detection information regarding the presence or absence of the paper T to the standby status management unit 107.

  In addition, the standby status management unit 107 includes the detection information regarding the paper T input by the paper detection unit 104, the number information regarding the number of sheets T input by the receiving unit 101, and the image formation instruction information including the type information regarding the paper T. Based on this, the standby state of the paper T in the standby unit 528 is managed. The standby status management unit 107 outputs information on the standby status to the carry-out control unit 105 and the rotation drive control unit 106.

  Further, the rotation drive control unit 106 controls the rotation drive unit 650 based on information from the standby state management unit 107. The carry-out control unit 105 controls the first cassette paper feed unit 51A to carry out the paper T from the first paper feed cassette 52A based on the information from the standby state management unit 107.

Specifically, the rotation drive control unit 106 causes the standby unit 528 to wait for the paper T based on the information input from the standby state management unit 107 or conveys the paper T toward the image forming unit GK. The rotational drive unit 650 is controlled depending on whether or not it is performed.
The carry-out control unit 105 also waits for a predetermined number of sheets T in order from the registration roller pair 80 side in the standby unit 528 based on the information input from the standby status management unit 107. To control.

In step ST6, the sheet T conveyed to the horizontal conveyance unit 528A is positioned in the conveyance width direction D2. Specifically, a positioning device 610 is disposed between the third roller pair 553 and the fourth roller pair 554 on the image forming unit GK side in the horizontal conveyance unit 528A. The paper T carried into the positioning device 610 is sequentially positioned by the positioning device 610 in the transport width direction D2.
Specifically, when the paper T is aligned in the positioning device 610 (when the carry-in detection unit 112 detects that the paper T is aligned in the width direction D2), the rotation drive control unit 106 includes the third roller pair 553 and The third rotation drive unit 653 and the fourth rotation drive unit 654 are controlled to stop the fourth roller pair 554.
The guide member driving unit 630 drives the guide member when the third rotation driving unit 653 and the fourth rotation driving unit 654 are controlled so that the rotation of the third roller pair 553 and the fourth roller pair 554 is stopped. Based on an instruction from the control unit 111, the first guide member 620a and the second guide member 620b are moved from the standby position to the positioning position.

  The positioning device 610 operates in this way, thereby positioning the loaded paper T in the transport width direction D2. After the positioning operation in the transport width direction D2 of the paper T is completed, the guide member driving unit 630 moves each of the first guide member 620a and the second guide member 620b from the positioning position based on an instruction from the guide member driving control unit 111. Move to the standby position. Thereafter, the rotational drive control unit 106 detects the end of the positioning operation of the positioning device 610 by a sensor (not shown) that detects the movement of the first guide member 520a or the second guide member 520b, for example, and the third roller pair 553 and The guide member driving unit 630 is controlled so that the fourth roller pair 554 can be rotated.

  In step ST <b> 7, the paper T positioned in the transport width direction D <b> 2 by the positioning device 610 based on the information input from the standby state management unit 107 is sequentially transported toward the registration roller pair 80. Accordingly, the paper T is sequentially conveyed toward the image forming unit GK in a suitable state after being positioned in the conveyance width direction D2.

  In step ST8, an image is formed on the first surface of the paper T by the image forming unit GK.

As illustrated in FIG. 5B, in step ST <b> 9, the control unit 102 determines whether to form an image on one side of the paper T or to form an image on both sides of the paper T based on the information output from the receiving unit 101. When images are formed on both sides of the paper T (YES), the process proceeds to step ST10. In this embodiment, when forming images on both sides of the paper T, first, after forming an image only on the first side of a predetermined number of papers T, the paper T is reversed and printed on the first side. An image is formed on the second surface of the predetermined number of sheets T. As a result, images are formed on both sides of the paper T. For example, the image forming unit GK continuously forms images on only the first surface of the five sheets of paper T, and then continuously on the second surface of the five sheets of paper T on which the image is formed on the first surface. Form an image.
When an image is formed on one side of the paper T (NO), the process proceeds to step ST18.

  In step ST10, the paper T is conveyed toward the switchback unit 560 in order to form a toner image on the second surface of the paper T. Specifically, the five sheets of paper T on which the image is formed on the first surface discharged from the fixing unit 9 sequentially pass through the eighth transport path 509, the first branching section 501 and the reverse transport path 520. Then, it is conveyed to the switchback unit 560. The paper T is turned upside down by the switchback unit 560.

  In step ST11, the guide member drive control unit 111 guides each of the first guide member 620a and the second guide member 620b so as to move or maintain each of the first guide member 620a and the second guide member 620b to the standby position. The member drive unit 630 is controlled.

  In step ST12, the paper T reversed by the switchback unit 560 is sequentially conveyed again to the image forming unit GK through the return conveyance path (fourth conveyance path) 55. For example, when double-sided printing is performed on five A4 landscape sheets T, the five A4 landscape sheets T on which images are formed on the first surface are reversed by the switchback unit 560 and returned to the return conveyance path (the fourth transport path). Are sequentially conveyed to the image forming unit GK via a conveyance path) 55.

  In step ST13, the paper T is transported to the horizontal transport unit 528A. Here, a portion from the first junction 511 to the image forming unit GK in the return conveyance path (fourth conveyance path) 55 is a conveyance path that is common to the paper feed conveyance path 521. Therefore, the paper T conveyed on the return conveyance path (fourth conveyance path) 55 can be conveyed to the horizontal conveyance unit 528A.

  In step ST14, similarly to step ST6 described above, the paper T is transported to the horizontal transport unit 528A.

  Here, the paper T whose front and back are reversed by the switchback unit 560 may be displaced in the transport width direction D2 by the reversing operation in the switchback unit 560. For this reason, the positioning device 610 disposed in the horizontal conveyance unit 528A can suppress the displacement of the position in the conveyance width direction D2 of the paper T due to the reversing operation in the switchback unit 560.

  In particular, the positioning device 610 is disposed in a common horizontal conveyance unit 528A to which the paper T carried out from the first paper feed cassette 52A and the paper T inverted during double-sided printing are conveyed. For this reason, the sheet T conveyed from the first sheet cassette 52A and the sheet T conveyed from the switchback unit 560 during double-sided printing are shifted by the common positioning device 610 in the conveyance width direction D2 of the sheet T. A positioning operation for adjusting the position is performed.

  Thus, the positioning device 610 becomes a positioning device for the paper T carried out from the first paper feed cassette 52A and a positioning device for the paper T carried out from the switchback unit 560. Therefore, since the color copying machine 1 according to the present invention does not need to have two positioning devices by sharing the two positioning devices, the device can be simplified and the cost of the device can be reduced. Can do.

  The positioning operation in step ST14 is a positioning operation in the conveyance width direction D2 of the paper T whose front and back are reversed in the switchback unit 560. Since the description of the operation in step ST14 is the same as that in step ST6, the description of the operation in step ST6 is incorporated.

  In step ST15, the paper T positioned by the positioning device 610 is sequentially conveyed toward the image forming unit GK. The rotation drive control unit 106 and the carry-out control unit 105 are based on the information from the standby state management unit 107 until all the number of sheets T in the number information received by the receiving unit 101 are conveyed to the image forming unit GK. Then, the control for conveying the paper T to the image forming unit GK is efficiently performed. Then, the positioning device 610 performs a positioning operation in the transport width direction D2 on all sheets T transported to the horizontal transport unit 528A.

  In step ST16, the paper T on which the image is formed on the first surface is sequentially conveyed to the image forming unit GK. As a result, an image is formed on the second surface of the paper T by the image forming unit GK.

  In step ST17, after an image is formed on the paper T by the image forming unit GK, the paper T is discharged from the paper discharge unit 50 to the outside of the case body BD, and the control ends.

  When an image is formed on one side of the paper T in step ST9 (NO), the process proceeds to step ST17, where the paper T is discharged from the paper discharge unit 50 to the outside of the case body BD, and the control ends.

According to the color copier 1 of the present embodiment having the above configuration, the following effects are exhibited.
The color copier 1 of the present embodiment is a paper feed conveyance path 521 that conveys the paper T carried out from the paper feed cassette 52 to the image forming unit GK, and is between the paper feed cassette 52 and the image forming unit GK. A paper feed conveyance path 521 having a horizontal conveyance unit 528A formed so as to cross from one side to the other side in the horizontal direction of the case body BD, and a reversing unit that reverses the paper T carried out from the image forming unit GK. 560 and a recycle conveyance path 523 that conveys the paper T that has been turned upside down by the reversing unit 560, and is disposed in the recycle conveyance path 523 that merges upstream in the conveyance direction of the horizontal conveyance unit 528A, and the horizontal conveyance unit 528A. A position regulating member 620 that regulates the position of the paper T in the transport width direction D2.

  Therefore, the positioning device 610 having the position regulating member 620 serves as a positioning device for the paper T carried out from the paper feed cassette 52 and a positioning device for the paper T carried out from the switchback unit 560. Accordingly, since the color copying machine 1 does not need to include the two positioning devices 610 by sharing the two positioning devices 610, the device can be simplified and the cost of the device can be reduced. Can do.

  Further, according to the color copier 1 of the present embodiment, the paper feed conveyance path 521 has the curved conveyance unit 528B continuously formed on the downstream side in the conveyance direction D1 of the horizontal conveyance unit 528A, and the horizontal conveyance unit 528A and the curved conveyance unit 528B function as a standby unit that waits for the paper T before being carried into the image forming unit GK. Therefore, the horizontal transport unit 528A can transport or wait for the paper T without being substantially bent or bent. Accordingly, the paper T conveyed to the horizontal conveyance unit (planar standby unit) 528A is conveyed or waited in a stable state. Further, the sheet T conveyed to the horizontal conveyance unit (planar standby unit) 528A is conveyed or waited in a state where the load applied by the conveyance path is suppressed. Accordingly, the positioning device 610 disposed in the horizontal conveyance unit (planar standby unit) 528A conveys the paper T in a stable state and a load applied to the paper T by the conveyance path is suppressed. Positioning in the width direction D2 can be suitably performed.

  Further, according to the color copier 1 of the present embodiment, the guide member driving unit 630 that moves the position regulating member 620 in the transport width direction D2, and the guide that positions the position of the paper T in the transport width direction D2 at a predetermined position. And a guide member drive control unit 111 that controls the member drive unit 630. Thereby, the color copier 1 of the present embodiment can suitably perform positioning in the transport width direction D2 of the paper T transported toward the image forming unit GK.

  Further, according to the color copier 1 of the present embodiment, one or a plurality of roller pairs 550 that are disposed in the vicinity of the position regulating member 620 in the horizontal conveyance unit 528A and convey the sheet T, and one or a plurality of rollers. One or a plurality of rotational driving units 650 that rotationally drive the roller pair 550, a second sensor 648 disposed along the horizontal conveying unit 528A, and the sheet T is a position regulating member based on the detection result from the second sensor 648 620 and the carry-in detection unit 112 that detects that the paper T is aligned in the width direction D2, and when the carry-in detection unit 112 detects that the paper T is aligned in the width direction D2 and the one or more rollers A rotation drive control unit 106 that controls the rotation drive unit 650 to stop the rotation of the pair 550, and the guide member drive control unit 111 is controlled by the rotation drive control unit 106. When the rotation driving unit 650 is controlled so that the rotation of the one or the plurality of roller pairs 550 is stopped, the position regulating member 620 controls the guide member driving unit 630 so that the sheet T is positioned at a predetermined position in the width direction D2. To do. Thereby, the color copier 1 of the present embodiment can suitably perform positioning in the transport width direction D2 of the paper T transported toward the image forming unit GK.

As mentioned above, although preferred embodiment was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above.
For example, in the above-described embodiment, the storage unit 52 includes the first paper feed cassette 52A, the second paper feed cassette 52B, and the third paper feed cassette 52C, but is not limited thereto. The storage unit 52 may be configured to include one or two sheet feeding cassettes.

  In the above-described embodiment, the case where the A4 size paper T is conveyed in the horizontal direction (A4 landscape paper T) is described, but the present invention is not limited to this. For example, it may be a case where A3 size paper T is conveyed in the vertical direction (A3 horizontal paper T).

  In the above-described embodiment, the toner image is indirectly transferred to the paper T by the intermediate transfer unit 200. However, the present invention is not limited to this. The intermediate transfer unit 200 may be configured to transfer the toner image directly to the paper T.

The type of the image forming apparatus of the present invention is not particularly limited, and may be a monochrome copier, a printer, a facsimile, or a complex machine thereof.
Further, the numbers of the intermediate roller pairs 550 and the rotation driving units 650 are not limited.
Further, the sheet-like transfer material is not limited to paper, and may be a film sheet, for example.

  DESCRIPTION OF SYMBOLS 1 ... Color copier (image forming apparatus), 2a, 2b, 2c, 2d ... Photosensitive drum (image carrier), 9 ... Fixing part, 16a, 16b, 16c, 16d ... Developing device, 52 ... ... Paper feed cassette (storage section), 521 ... Feed conveyance path (sheet conveyance path), 523 ... Recycle conveyance path, 560 ... Switchback section (reversing section), 620 ... Position restricting member, D1 ... Transport direction, D2: Transport width direction (width direction), BD: Case body (housing), GK: Image forming unit, T: Paper (transferred material)

Claims (4)

A housing,
A storage section for storing a sheet-like transfer material;
An image forming unit disposed on the upper side in the vertical direction of the storage unit and forming an image on the transfer material;
A sheet conveyance path for conveying the material to be transferred unloaded from the storage unit to the image forming unit, and between the storage unit and the image forming unit, from one side to the other side in the horizontal direction of the housing A sheet conveyance path having a horizontal conveyance portion formed so as to cross over
A reversing unit for reversing the front and back of the material to be transferred carried out from the image forming unit;
A recycle conveyance path for conveying the material to be transferred that has been turned upside down by the reversal section, and a recycle conveyance path that joins the upstream side in the conveyance direction of the horizontal conveyance section;
An image forming apparatus comprising: a position regulating member that is disposed in the horizontal conveyance unit and regulates a position in a width direction that is a direction orthogonal to the conveyance direction of the transfer material. The sheet conveying path has a curved conveying portion formed continuously on the downstream side in the conveying direction of the horizontal conveying portion,
The horizontal conveyance unit and the curved conveyance unit function as a standby unit that waits for the transfer material before being carried into the image forming unit,
The image forming apparatus according to claim 1, wherein the horizontal conveying unit is capable of waiting without substantially bending or bending one or a plurality of the transfer materials. A regulating member driving unit that moves the position regulating member in the width direction;
The image forming apparatus according to claim 1, further comprising: a regulating member driving control unit that controls the regulating member driving unit so that the position in the width direction of the transfer material is positioned at a predetermined position. One or a plurality of roller pairs arranged in the vicinity of the position regulating member in the horizontal transport unit, and sandwiching and transporting the transferred material;
One or a plurality of rotation driving units for rotating the one or more roller pairs;
One or a plurality of detection members arranged along the horizontal conveyance unit;
A carry-in detector that detects that the material to be transferred is aligned with the position regulating member in the width direction based on detection results from the one or more detection members;
Rotation drive that controls the rotation drive unit to stop the rotation of the one or the plurality of roller pairs when the carry-in detection unit detects that the transfer material is aligned with the position regulating member in the width direction. A control unit,
When the rotation drive unit is controlled by the rotation drive control unit so that the rotation of the one or the plurality of roller pairs is stopped, the position control member moves the transfer material in the width direction. The image forming apparatus according to claim 3, wherein the restriction member driving unit is controlled to be positioned at a predetermined position.

Images