JP2004070374A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which permits rapid and easy jam processing in case of the occurrence of a failure, such as a jamming, and can consequently improve the maintainability of the apparatus in a relay conveyance means for conveying a paper formed in the apparatus body to a paper post processing device. <P>SOLUTION: An image forming section 210 is arranged below an original reading section 100 and a first paper ejection section 234 for ejecting a paper formed with images by the section 210 is formed. A relay conveyance path 300a for conveying the paper from the section 210 to the post processing device 300 is disposed between the section 100 and the section 234. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an image forming apparatus provided with a post-processing device in a multifunction peripheral having a copying function, a facsimile function, and a printing function.

2. Description of the Related Art Conventionally, as shown in FIG. 42, an MFP having a copying function, a FAX function, and a printing function includes a document reading unit 1010 for reading a document, and an image forming apparatus main body 1020 as a printing unit for printing image information on paper. And a sheet feeding / cassette means 1030 for storing and feeding sheets.

In the multifunction peripheral having the above-described configuration, a space is formed below the document reading unit 1010 so that the image forming unit 1021 of the image forming apparatus main body 1020 is vertical so as to form a U-shape when viewed from the operation surface side. And a discharging unit 1040 for discharging the sheet conveyed from the sheet conveying path 22 of the image forming apparatus main body 1020 is formed in the space.

In this way, by discharging the printed paper into the installation surface of the device, the installation area of the device is reduced compared to the case where the printed paper is discharged outside the device body. can do. In such an image forming apparatus, even if a post-processing apparatus for performing post-processing such as stapling processing on printed paper is mounted outside the apparatus main body, the post-processing apparatus can be attached to a conventional image forming apparatus. The installation area can be reduced as compared with the case of mounting.

As an example in which the above-described paper post-processing device is attached to an image forming device that discharges a printed sheet in the installation surface of the above-described device, for example, an “image forming device” disclosed in Patent Document 1, There is an “image forming apparatus” disclosed in Patent Document 2.

The image forming apparatus disclosed in Patent Document 1 has a configuration in which a sheet post-processing apparatus 1050 is disposed on a side surface of an image forming apparatus main body 1020 as shown in FIG. The sheet from the image forming apparatus main body 1020 is carried into the sheet post-processing apparatus 1050 by the relay conveying means 1060 provided in the discharging means 1040 (space) formed below the document reading unit 1010. ing.

Further, as shown in FIG. 46, the image forming apparatus disclosed in Patent Document 2 has the same configuration as that of Patent Document 1, that is, a sheet post-processing apparatus 1050 arranged on the side of the image forming apparatus main body 1020. Is configured such that a sheet from the image forming apparatus main body 1020 is conveyed by a relay conveyance unit 1060 provided in a discharge unit 1040 (space portion) formed below the document reading unit 1010.

In any of the image forming apparatuses disclosed in Patent Document 1 and Patent Document 2 described above, when the sheet post-processing device 1050 is not used, the sheet is discharged to the upper surface 1060a of the relay conveyance unit 1060. In the case of Literature 1, as shown in FIG. 45, by moving the relay conveyance means 1060 up and down, in addition to the upper surface 1060a of the relay conveyance means 1060, a space formed below the relay conveyance means 1060 The paper can also be discharged.
JP-A-10-324444 (publication date: December 8, 1998) JP-A-11-157725 (publication date: June 15, 1999)

However, in the image forming apparatuses disclosed in Patent Literature 1 and Patent Literature 2, when a jam occurs in the relay conveyance unit 1060 while using the sheet post-processing device 1050, the paper is placed on the relay conveyance unit 1060. If there is, it is necessary to remove it, open the upper surface 1060a of the relay conveyance means 1060, and remove the paper causing the jam.

As described above, in the image forming apparatuses disclosed in Patent Literature 1 and Patent Literature 2, when a jam occurs in the relay conveyance unit 1060, the sheet is discharged onto the upper surface 1060a of the relay conveyance unit 1060. For example, there is a problem that it takes time and trouble to remove the paper, such as removing the paper, removing the paper jam by opening the surface of the relay conveyance means 1060 with no paper on the relay conveyance means 1060, This leads to a decrease in the maintainability of the device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to cause a problem such as a paper jam in a relay conveyance unit that conveys a sheet formed in an apparatus main body to a sheet post-processing apparatus. It is an object of the present invention to provide an image forming apparatus capable of performing jam processing quickly and easily in this case, thereby improving the maintainability of the apparatus.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. An image forming section, and a sheet post-processing section attached to an apparatus main body including the image forming section and performing post-processing of a sheet on which an image is formed. In an image forming apparatus in which a space is formed as a discharge unit for discharging a sheet on which an image is formed, an upper discharge port and a lower discharge port for discharging the sheet are disposed in the space. And a relay transport path connected to the upper discharge port for transporting a sheet from the image forming section to the sheet post-processing section.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. An image forming unit for performing post-processing of a sheet on which an image is formed by the image forming unit, the image forming unit includes an image forming unit below the document reading unit. In addition to forming a space portion in which a discharge port for discharging the discharged paper is formed, a relay conveyance path that is connected to the discharge port and conveys the paper from the image forming unit to the paper post-processing unit is formed. The relay conveyance path is characterized in that at least a part thereof is provided in a direction perpendicular to the paper conveyance direction, and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. I have.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. An image forming unit for performing post-processing of a sheet on which an image is formed by the image forming unit, the image forming unit includes an image forming unit below the document reading unit. A space portion provided with a discharge port for discharging the formed sheet, the sheet post-processing portion is attached to the space portion, and the relay conveyance path is at least partially perpendicular to the sheet conveyance direction. It is characterized in that it is provided so as to be openable downward in the direction and with the end opposite to the surface operated by the operator of the apparatus as a fulcrum.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. An image forming section, and a sheet stack section attached to the apparatus main body including the image forming section and configured to discharge a sheet on which an image has been formed. The image forming section includes an image forming section below the document reading section. In the image forming apparatus in which a space as a discharge unit for discharging the formed paper is formed, an upper discharge port and a lower discharge port for discharging the paper are disposed in the space, A relay conveyance path connected to the discharge port and conveying the sheet from the image forming section to the sheet stacking section is formed.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. An image forming apparatus, and a sheet stacking section for discharging a sheet on which an image is formed by the image forming section, an image is formed by the image forming section below the document reading section. A space provided with a discharge port for discharging the sheet is formed, and a relay conveyance path that is connected to the discharge port and conveys the sheet from the image forming unit to the sheet stack unit is formed. The relay conveyance path is characterized in that at least a part thereof is provided in a direction perpendicular to the paper conveyance direction and is openable downward with an end opposite to a surface operated by an operator of the apparatus as a fulcrum.

The relay conveyance path may be provided on the back of the document reading unit.

The relay conveyance path may be provided between the document reading unit and the space.

(4) The relay conveyance path may be provided with a jam detecting unit for detecting that a sheet is jammed in the relay conveyance path.

In order to solve the above-described problems, an image forming apparatus of the present invention forms a document on a sheet based on image information of a document read by the document reading unit that reads image information of the document. In an image forming apparatus provided with an image forming unit and a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of an image-formed sheet, A space surrounded by the outer peripheral wall of the apparatus body is formed, and a relay conveyance path for conveying a sheet from the image forming unit to the sheet post-processing unit is formed between the document reading unit and the space. The relay conveyance path is provided so as to be openable downward at least partially in a direction perpendicular to the sheet conveyance direction and with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. .

In order to solve the above-described problems, an image forming apparatus according to the present invention forms an image on a sheet based on image information of a document read by the document reading unit that reads image information of the document. In the image forming apparatus provided with an image forming unit and a paper post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of an image-formed sheet, below the document reading unit, A discharge unit for discharging the sheet on which the image is formed by the image forming unit is formed, and the sheet is conveyed from the image forming unit to the sheet post-processing unit between the document reading unit and the discharge unit. The relay transport path is formed, and at least a part of the relay transport path is provided in a direction perpendicular to the paper transport direction, and can be opened downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Being done It is a symptom.

In order to solve the above-described problems, an image forming apparatus of the present invention forms a document on a sheet based on image information of a document read by the document reading unit that reads image information of the document. In an image forming apparatus provided with an image forming unit and a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of an image-formed sheet, A discharge section for discharging the sheet on which the image is formed by the image forming section is formed, and a relay conveyance path for conveying the sheet from the image forming section to the sheet post-processing section is formed on the back of the document reading section. The relay conveyance path is characterized in that at least a part thereof is provided in a direction perpendicular to the paper conveyance direction, and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. I have.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. In the image forming apparatus provided with an image forming unit and a paper post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of an image-formed sheet, below the document reading unit, A discharge unit for discharging the sheet on which the image is formed by the image forming unit is formed, and a relay conveyance path that conveys the sheet from the image forming unit to the sheet post-processing unit is provided on a ceiling surface of the discharge unit. The relay conveyance path is formed so as to be openable downward at least partially in a direction perpendicular to the paper conveyance direction and with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. And

(4) The relay conveyance path may be provided with a jam detecting unit for detecting that a sheet is jammed in the relay conveyance path.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. In the image forming apparatus provided with an image forming unit and a paper post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of an image-formed sheet, below the document reading unit, A space is formed as a discharge unit that discharges the sheet on which the image is formed by the image forming unit, and is surrounded by the outer peripheral wall of the apparatus main body, and is located above the discharge unit and at the back of the document reading unit. A relay transport path for transporting a sheet from the image forming section to the sheet post-processing section is formed.

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. In the image forming apparatus provided with an image forming unit, a sheet, which is surrounded by an outer peripheral wall of an apparatus main body including the image forming unit and has an image formed by the image forming unit, is discharged below the document reading unit. A space portion as a discharge portion is formed, and a relay conveyance path that conveys paper from the image forming portion to a discharge portion different from the space portion is provided above the discharge portion and on the back of the document reading portion. The image forming apparatus is characterized in that the relay conveyance path is provided with a switchback mechanism for conveying the sheet on which the image is formed on one side again to the image forming unit when forming an image on both sides of the sheet. .

According to another aspect of the present invention, there is provided an image forming apparatus configured to form an image on a sheet based on image information of a document read by the document reading unit. In the image forming apparatus provided with an image forming unit, a sheet, which is surrounded by an outer peripheral wall of an apparatus main body including the image forming unit and has an image formed by the image forming unit, is discharged below the document reading unit. A space portion as a discharge portion is formed, and a relay conveyance path that conveys paper from the image forming portion to a discharge portion different from the space portion is provided above the discharge portion and on the back of the document reading portion. The relay conveyance path is formed so as to be openable in the space.

(4) The relay conveyance path may be provided with a jam detecting unit for detecting that a sheet is jammed in the relay conveyance path.

The jam detecting unit includes an optical light emitting unit, a light receiving unit for receiving irradiation light from the light emitting unit, and an arm member that cuts off the light receiving unit by conveying and abutting a sheet. It may consist of a sensor.

The relay transport path may be unitized so as to be detachable from the apparatus main body.

れ ば One embodiment of the present invention will be described as follows.

The image forming apparatus according to the present embodiment includes a document reading section 100, an image forming apparatus main body 200, a post-processing apparatus 300, and a sheet stacking section 400 as shown in FIG.

The document reading section 100 has a document table 101 made of transparent glass or the like on the upper surface. A scanner optical system 111 for optically reading a document (not shown) placed on the document table 101 is disposed on the document table 101.

The scanner optical system 111 includes an exposure light source 112 for irradiating a document (not shown) placed on the document table 101 with light, and a photoelectric conversion element (for receiving light reflected by the document). A plurality of reflecting mirrors 113 for guiding light reflected by a document to the photoelectric conversion element 115 between the exposure light source 112 and the photoelectric conversion element 115; An imaging lens 114 for forming an image of the light guided by the reflecting mirror 113 on the photoelectric conversion element 115 is provided.

The output signal from the photoelectric conversion element 115, that is, the document image data, is subjected to image processing and then sent to an LSU (laser scanning unit) 201 provided in the image forming apparatus main body 200. I have.

The image forming apparatus main body 200 is roughly divided into an image forming unit 210 for forming (printing) an image on the transfer paper P, and a housing for accommodating the transfer paper P and transporting the transfer paper P to the image forming unit 210. And a sheet feeding / conveying section 220.

The image forming section 210 includes the LSU 201 and a photoconductor 211 on which an electrostatic latent image is formed by irradiating a laser beam from the LSU 201 to the surface.

The photoconductor 211 has a drum shape that is driven to rotate in the direction of the arrow. Around the photoconductor 211, a developing point is formed from the irradiation point of the laser beam from the LSU 201 toward the rotation direction of the photoconductor 211. An apparatus 212, a transfer charger 213, a static eliminator 214, and a main charger 215 are arranged.

The developing device 212 develops the electrostatic latent image on the surface of the photoconductor 211 exposed by the laser beam into a visible image (toner image) using toner, and the transfer charger 213 transfers the toner image on the photoconductor 211. After transfer to the paper P, the charge eliminator 214 removes the charge remaining on the photoconductor 211 after the transfer of the toner image, and the main charger 215 cleans the surface of the photoconductor 211 from which the residual charge has been removed. It is charged to a predetermined potential. Further, although not shown, a cleaning device is provided between the transfer charger 213 and the static eliminator 214 for removing the toner remaining on the photoconductor 211 after the transfer of the toner image.

The LSU 201 is not limited to the image data of the original read by the above-described original reading unit 100, and may be image information from an external device such as a computer (not shown) connected to the outside or a facsimile transmitted by communication or the like. A laser is applied to the photoconductor 211 based on the information.

Therefore, the present image forming apparatus is capable of reading a document image by the document reading unit 100 and forming an image on a sheet, a facsimile function of forming an image on a sheet based on FAX information through communication or the like, and an external device such as a computer. Is a multifunction peripheral having a print function of forming an image on a sheet based on the image information.

The paper feeder 220 has a paper cassette 221 for stocking the transfer paper P and feeding the transfer paper P, and a manual tray for feeding the transfer paper P from the side of the image forming apparatus main body 200. 222 are provided.

At the leading end of the paper cassette 221 on the transfer paper P feed side, a call-in roller 223 for feeding the transfer paper P stored in the paper cassette 221 and, although not shown, the stored transfer paper P, A roller and a sheet separating portion including a friction sheet member or a reverse rotation roller are arranged so that the sheet can be sent out one sheet at a time.

A pickup roller 224 for feeding out the transfer paper P to guide the transfer paper P to an image forming position in the image forming unit 210 and a first paper feed path 225 are provided on the downstream side in the transfer paper P conveyance direction of the above-described intraction roller 223. I have.

On the other hand, at the leading end of the manual feed tray 222 on the transfer paper P feed side, a feed roller 226 for feeding the transfer paper P on the manual feed tray 222 and an image forming unit A pickup roller 227 for sending out to guide to a position and a second paper feed path 228 are provided.

Before the image forming position of the image forming unit 210, the transfer paper P fed from the first paper feed path 225 or the second paper feed path 228 is transferred at a predetermined timing to transfer the toner image on the photoconductor 211. A registration roller 229 for transporting to a position (image forming position) is provided.

The registration roller 229 is moved to either the first paper path 225 or the second paper path 228 by a pre-registration detection switch (not shown) provided in the first paper path 225 and the second paper path 228. Based on a detection signal indicating that the transfer paper P has passed through the above, the transfer is performed so that the toner image on the photoconductor 211 and the transfer paper P are aligned.

A fixing roller for fixing the toner image transferred onto the transfer paper P by heat downstream of the transfer position where the toner image on the photosensitive member 211 is transferred onto the transfer paper P in the transfer paper P transport direction. 230 are provided.

Downstream of the fixing roller 230 in the transporting direction of the transfer paper P, a paper transport path 231 for transporting the fixed transfer paper P, and the transfer paper P transported via the paper transport path 231 are transferred to the image forming apparatus main body 200. A first paper transport path 233 for guiding the paper to a paper discharge roller 232 for discharging to the outside is provided.

The transfer paper P discharged from the paper discharge roller 232 is discharged to a first paper discharge unit 234 formed below the document reading unit 100. As shown in FIG. 1, the first paper discharge unit 234 is formed below the document reading unit 100, on the side of the image forming unit 210 of the image forming apparatus main body 200, and on the upper side of the paper cassette 221. It is formed in the space. The space here indicates an area below the document reading unit 100 and surrounded by the outer peripheral wall of the image forming apparatus main body 200.

On the upstream side of the first paper transport path 233 in the transport paper P transport direction, a second paper for switching and leading the transfer paper P to either the first paper transport path 233 or the paper transport path 236 leading to the post-processing device 300 is provided. One switching gate 235 is provided. As shown in FIG. 2, the first switching gate 235 is provided to be rotatable in directions indicated by arrows c and d with a branch point between the first paper transport path 233 and the paper transport path 236 as a fulcrum. That is, when the transfer paper P is guided to the first paper transport path 233, the transfer paper P rotates in the direction of arrow d to close the paper transport path 236, and when the transfer paper P is guided to the paper transport path 236, the arrow c , And closes the first sheet transport path 233.

In addition, the paper feeding and conveying unit 220 is provided with a reverse conveying path 237 parallel to the paper conveying path 231 as shown in FIG. The reversing conveyance path 237 is a conveyance path used for double-sided printing for forming an image on both sides of the transfer paper P. The transfer paper P is conveyed in a direction opposite to the conveyance direction of the paper conveyance path 231 described above. The sheet is conveyed to the registration roller 229.

Therefore, the transfer paper P on which double-sided printing is performed is formed with an image on one side, and is conveyed to the paper conveyance path 231. Then, the transfer paper P is once guided to the post-processing apparatus 300 by the above-described paper conveyance path 236. , And is conveyed again to the reverse conveyance path 237 through the paper conveyance path 236. The switchback function of the post-processing device 300 will be described later.

Then, the transfer paper P conveyed to the reverse conveyance path 237 is conveyed to a transfer position of the toner image via the registration roller 229, the toner image is transferred to a surface on which no image is formed, and is thermally fixed by the fixing roller 230. Then, the sheet is sent to the sheet conveying path 231.

A switching gate 238 is provided at a branch point between the paper transport path 231 and the reverse transport path 237 so as to close the paper transport path 231 when the transfer paper P is transported to the reverse transport path 237. To prevent the transfer paper P from being transported to the paper transport path 231.

That is, as shown in FIG. 2, the switching gate 238 is rotatably provided in the directions indicated by arrows a and b. When the transfer sheet P is guided to the sheet transport path 231, the switching gate 238 is rotated in the direction indicated by arrow b. When the transfer paper P is guided to the reverse transport path 237 by closing the reverse transport path 237, the paper transport path 231 is closed by rotating in the direction of arrow a.

When the transfer paper P is guided to the reverse transport path 237, it is necessary to rotate the first switching gate 235 in the direction of arrow c so that the paper transport path 236 is opened.

As shown in FIG. 1, the post-processing apparatus 300 transfers the transfer paper P transported from the paper transport path 236 of the image forming apparatus main body 200 to an escape path 302 as a second paper transport path described later or a third paper transport path. And a paper discharge roller 318 for discharging the transfer paper P transported on the paper transport path 301 to the escape path 302 or the staple tray 303.

(4) The escape path 302 and the staple tray 303 form a relay conveyance path 300a for relaying and transferring the transfer sheet P from the image forming apparatus main body 200 to a sheet stack section 400 serving as a sheet post-processing section.

{Circle around (1)} The paper transport path 301b for transporting the paper from the image forming apparatus main body 200 to the relay transport path 300a is formed by the paper transport path 301.

In other words, the post-processing device 300 is constituted by the relay conveyance path 300a and the paper conveyance path 300b. As shown in FIG. 1, the relay conveyance path 300a is unitized so as to be detachable from the paper conveyance path 300b around the paper discharge roller 318. That is, the relay conveyance path 300a is unitized so as to be detachable from the image forming apparatus main body 200.

Accordingly, when the post-processing device 300 is not used, the relay conveyance path 300a can be removed, and the maintenance can be performed by removing the relay conveyance path 300a. Therefore, the maintenance performance of the entire apparatus can be improved. it can.

{Circle around (1)} As shown in FIG. 1, the relay conveyance path 300 a is formed between the document reading unit 100 and the space serving as the first paper discharge unit 234. From another angle, it can be said that the relay conveyance path 300a is provided on the surface (back surface) of the document reading unit 100 opposite to the document table 101 (back surface). Further, it can be said that the relay conveyance path 300a is formed on the upper surface (ceiling surface) of the space that is the first paper discharge unit 234.

According to the above configuration, the relay conveyance path 300a that conveys the sheet from the image forming apparatus main body 200 to the post-processing apparatus 300 is between the document reading unit 100 and the space surrounded by the outer peripheral wall of the image forming apparatus main body 200. Therefore, the relay conveyance path 300a is formed above the first paper discharge unit 234 where the paper not conveyed from the image forming apparatus main body 200 to the post-processing apparatus 300 is discharged.

Accordingly, when a paper jam occurs in the relay conveyance path 300a, the sheet is not discharged onto the upper surface of the relay conveyance path 330a, so that the sheet not conveyed from the image forming apparatus main body 200 to the post-processing apparatus 300 is removed. Even if the paper remains on the first paper discharge unit 234 to be discharged, the jam processing can be performed without removing the paper.

Therefore, when a problem such as a paper jam occurs in the relay conveyance path 300a that conveys the sheet formed in the image forming apparatus main body 200 to the post-processing apparatus 300, the jam can be quickly and easily performed. Can be improved in maintainability.

A second switching gate 304 is provided at a branch point between the escape path 302 and the staple tray 303 on the downstream side of the paper transport path 301 in the transport paper P transport direction. As shown in FIG. 3, the second switching gate 304 is provided so as to be rotatable in the directions of arrows e and f with the branch point as a fulcrum. When the transfer sheet P rotates in the direction e and guides the transfer paper P to the staple tray 303, the transfer paper P rotates in the direction of arrow f.

The escape path 302 is a transport path that transports the transfer paper P that has not been subjected to post-processing such as stapling, and the transport portion of the transfer paper P is substantially the same as the document table 101 of the document reading unit 100 as shown in FIG. The transfer paper P is formed so as to be parallel, and is conveyed in a substantially horizontal state (substantially horizontal state) to a paper stack unit 400 described later.

A first paper discharge path 305 and a second paper discharge path 306 are provided on the downstream side of the escape path 302 in the transfer paper P transport direction. A third switching gate 307 is provided at a branch point between the first paper discharge path 305 and the second paper discharge path 306, and the transfer paper P conveyed through the escape path 302 is discharged from the first paper discharge path 302 as necessary. The sheet is conveyed by being switched to either the paper path 305 or the second paper discharge path 306. That is, as shown in FIG. 4, the third switching gate 307 is provided rotatably in the directions of arrows g and h with the branch point between the first paper discharge path 305 and the second paper discharge path 306 as a fulcrum. When the transfer paper P is guided to the first discharge path 305, the transfer paper P rotates in the direction of arrow g. When the transfer paper P is guided to the second discharge path 306, the transfer paper P rotates in the direction of arrow h. It has become.

On the other hand, the staple tray 303 is a transport path for transporting the transfer paper P on which post-processing such as staple processing is performed. As shown in FIG. 1, the staple tray 303 is provided below the escape path 302 and substantially in parallel with the escape path 302. The transfer sheet P is transported to the sheet stacking section 400 in a substantially horizontal state, similarly to the escape path 302.

In the staple tray 303, the transfer paper P is stocked and aligned in a substantially horizontal state, and the staple unit 308 described later performs staple processing on the transfer paper P aligned in the horizontal state. Has become.

A staple unit 308 for performing staple processing and a discharge roller 309 for discharging a bundle of transfer paper P stapled by the staple unit 308 are provided downstream of the staple tray 303 in the transfer paper P transport direction. Is provided.

The discharge roller 309 discharges the transfer paper P branched from the escape path 302 by the third switching gate 307 and conveyed through the second discharge path 306. Note that a paper detection sensor B (FIG. 8) for detecting the passage of the transfer paper P is provided on the paper discharge roller 309 before the transfer paper P is obtained.

The post-processing device 300 having the above-described configuration is provided between the document reading unit 100 and a space formed below the document reading unit 100, so that a space for sheet post-processing is formed on the installation surface of the image forming apparatus. Will be done. Accordingly, the installation area of the image forming apparatus including the post-processing apparatus 300 can be reduced, so that the degree of freedom for installing the image forming apparatus increases.

Further, in the post-processing apparatus 300, post-processing such as alignment of the image-formed transfer paper P and stapling is performed in a substantially horizontal state, so that post-processing such as alignment of the transfer paper P and stapling is performed. Can be performed in the same position. This eliminates the deformation of the transfer paper P bundle and the disturbance of the alignment that occur when the aligned transfer paper P bundle is conveyed to the staple position, and ensures that post-processing such as stapling is performed with the transfer paper P bundle in a state where the transfer paper P bundle is in order. Can be.

The sheet stacking section 400 stacks the transfer sheets P that have passed through the post-processing device 300. As shown in FIG. 1, a first sheet stack tray 401 as a second sheet discharging section, and a third sheet discharging section And a second sheet stack tray 402 as a copy unit.

The transfer paper P discharged from the escape path 302 of the post-processing device 300 via the first paper discharge path 305 is stacked on the first paper stack tray 401. That is, the transfer paper P that has passed through the post-processing device 300 but has not been subjected to post-processing such as stapling is stacked on the first paper stack tray 401.

On the other hand, the transfer paper P discharged from the paper discharge roller 309 via either the escape path 302 of the post-processing device 300 or the staple tray 303 is stacked on the second paper stack tray 402. That is, the transfer paper P mainly subjected to post-processing such as stapling is stacked on the second paper stack tray 402, but the transfer paper P not subjected to post-processing such as stapling is also stacked. .

{Circle around (2)} The second paper stack tray 402 moves up and down in accordance with the amount of transfer paper P loaded. That is, as the amount of transfer paper P stacked increases, the second paper stack tray 402 moves downward from a predetermined position. Therefore, when it is necessary to stack a large amount of the transfer paper P that has not been subjected to the stapling process or the like, the transfer paper P is discharged from the escape path 302 to the second paper stack tray 402 via the second paper discharge path 306. become.

As shown in FIG. 5, the staple unit 308 includes a stopper 501 provided at the leading end of the transfer paper P in the staple tray 303 in the transport direction, and abutting against the leading end of the transfer paper P transported from the staple tray 303. A paper leading end pressing lever 502 for pressing the leading end of the transfer paper P in contact with the stopper 501, a stapler 503 (FIG. 6) for performing staple processing on the transfer paper P, and a transfer paper P having been subjected to the stapling processing. And a feed-out roller 504 for feeding the paper to the paper discharge roller 309.

(6) An alignment member 505 for aligning the transfer sheet P in the width direction is provided near the staple unit 308 as shown in FIG.

As shown in FIGS. 5 and 6, the stopper 501 is formed of a member having a substantially L-shaped cross section, and is rotatably supported at an end opposite to the end abutting on the transfer paper P. When P is sent out, it rotates downward.

The paper leading end pressing lever 502 is formed on both sides of the stopper 501 and is inclined obliquely from above the staple tray 303 toward the downstream side in the transport direction of the transfer paper P at a gentle angle close to being parallel to the staple tray 303. It has a sagging shape. The paper front end pressing lever 502 is urged downward by a spring (not shown), presses down while guiding the transfer paper P even if the front end of the transfer paper P is curled, and is located on both sides of the stopper 501, The leading edge of the transfer sheet P is given a sense of rigidity to prevent misalignment due to deformation or damage when the edge of the transfer sheet P hits the stopper 501.

A roller member 506 that is orthogonal to the stopper 501 and rotatable with respect to the paper front end pressing lever 502 is provided at the front end of the paper front end pressing lever 502. Thereby, when the width direction of the transfer sheet P is aligned by the alignment member 505 while being pressed by the sheet front end pressing lever 502, the resistance between the sheet front end pressing lever 502 and the transfer sheet P can be reduced. it can.

As shown in FIG. 6, the stapler 503 is arranged so that stapling can be performed at the left corner of the leading end of the transfer sheet P in the transport direction.

5) As shown in FIGS. 5 and 6, the feed roller 504 is formed of a half-moon-shaped member, and is rotatable by a support shaft 507 extending in the width direction of the transfer paper P. That is, when the delivery roller 504 rotates in the direction of the arrow, the half-moon portion 504a protrudes from the opening 303a formed in the staple tray 303, pushes up the transfer paper P on the staple tray 303, and discharges the paper. It is sent to the side.

The feed roller 504 is on standby so that the half-moon portion 504a is on the lower side and the flat portion 504b is on the upper side so that the half-moon portion 504a is substantially parallel to the transfer paper P mounting surface of the staple tray 303 so as not to protrude from the mounting surface. are doing.

The feed roller 504 is driven by a motor 508 as a driving means, and the stopper 501 is connected to a drive shaft 508a of the motor 508. That is, the stopper 501 rotates downward in conjunction with the rotation of the delivery roller 504 in the direction of the arrow. This makes it possible to use the same drive source for the stopper 501 and the feed roller 504, thereby reducing the size of the apparatus.

(4) When the transfer sheet P is sent in the direction of the discharge roller 309, the stopper 501 is automatically moved downward just by rotating the sending roller 504, so that the transfer sheet P can be sent out smoothly.

Next, a mechanism for aligning sheets on the staple tray 303 will be described below.

As shown in FIG. 6, the alignment member 505 is provided so as to be movable in the width direction of the transfer sheet P, that is, in the direction orthogonal to the transfer direction of the transfer sheet P, and is adjacent to the stapler 503 of the staple tray 303. The transfer paper P is movable toward a fixed wall 509 provided along the transport direction of the transfer paper P. The operation of the alignment member 505 may be any time before the stapling by the stapler 503.

As shown in FIG. 7, the driving mechanism of the alignment member 505 includes a driving motor 510 provided as a driving source on the staple tray 303, and a pulley 510a for transmitting the rotational force of the driving motor 510. A drive belt 511 stretched around the pulley 510a, a pulley 512 stretching the drive belt 511, a drive gear 512a rotating in conjunction with the pulley 512, meshing with the drive gear 512a, And a rack 513 connected to the alignment member 505.

That is, the driving force of the driving motor 510 is transmitted to the driving gear 512a via the driving belt 511, and the aligning member 505 is connected to the rack 513 meshing with the driving gear 512a.

Therefore, the rotation of the drive motor 510 causes the alignment member 505 to move in the direction of the arrow, that is, toward the fixed wall 509.

The state shown in FIG. 7, that is, the state in which the alignment member 505 is located at the end of the staple tray 303 in the width direction of the transfer sheet P is defined as a home position (first standby position). The moving speed and the moving amount of the alignment member 505 are controlled by the number of pulses input to the drive motor 510. That is, when the alignment of the transfer sheet P in the width direction is completed, the drive motor 510 rotates in the reverse direction, moves the alignment member 505 away from the fixed wall 509, and returns to the first standby position. It is.

The operation of the alignment member 505 will be specifically described below with reference to FIG.

The alignment member 505 operates in a direction perpendicular to the transfer direction of the transfer sheet P, and feeds the sheet size obliquely from the first standby position to the sheet size based on the sheet size information sent from the main body. In consideration of the variation in the center, the robot stands by at a position about +3 mm to +5 mm apart (hereinafter, referred to as a second standby position).

The alignment member 505 detects that the transfer paper P has been stored in the staple tray 303, that is, the paper detection sensor A provided on the paper transport path 301 or the paper detection sensor C provided on the staple tray 303 (FIG. 8), the aligning operation is started, and the edge of the transfer sheet P opposite to the edge of the transfer sheet P in contact with the alignment member 505 contacts the fixed wall 509 on the staple tray 303. After that, the transfer paper P is further pushed in by about +1 mm to +3 mm from the width thereof, and then returns to the second standby position in preparation for the next transfer paper P to be inserted. The alignment member 505 repeats the above operation every time the transfer paper P is input.

Subsequently, after the number of sheets set by the operator has been inserted and the alignment has been completed, the alignment member 505 waits at the paper size position and holds the aligned transfer paper P so as not to shift until the staple processing is completed. Further, when the transfer paper P is discharged, the transfer paper P waits for the completion of discharge at a position where the transfer paper P does not become a resistance and is not conveyed extremely obliquely, that is, a second standby position.

Here, the details of the escape path 302 and the staple tray 303 will be described below with reference to FIGS.

As shown in FIG. 8, the escape path 302 is provided with a plurality of pairs of transport rollers 310 for transporting the transfer paper P so as to sandwich the same. These transport rollers 310 are driven by driving means (not shown).

(4) The staple tray 303 has two alignment portions (recesses) for aligning sheets, that is, a first alignment portion 311 and a second alignment portion 312.

The first alignment portion 311 is formed ahead of the second alignment portion 312 in the transfer paper P transport direction, and has a downwardly inclined surface 311a opposite to the transfer paper P transport direction; And the lowermost vertical surface 311b.

On the other hand, the second aligning portion 312 is formed behind the first aligning portion 311 in the transfer paper P transport direction, and has an inclined surface 312a inclined downward and opposite to the transfer paper P transport direction; 312a and the lowermost vertical surface 312b.

In the staple tray 303, the first aligning unit 311 and the second aligning unit 312 align the transfer paper P of a standard paper size, for example, the first aligning unit provided in front of the transfer paper P transport direction. 311 is formed so as to be suitable for the alignment of the transfer paper P of the B5 size and the A4 size, and the second alignment unit 312 provided behind the transfer paper P in the transport direction of the transfer paper P aligns the transfer paper P of the B4 size and the A3 size. It is formed so as to be suitable for.

Further, since the first alignment portion 311 and the second alignment portion 312 form a concave space between the escape path 302 and the space, a paper jam occurs in the staple tray 303 due to the space. In this case, the transfer paper P in the staple tray 303 can be easily removed.

Further, the staple tray 303 is provided with a feeding member 313 for folding the transfer paper P aligned by the first alignment unit 311 and the second alignment unit 312 to the staple position of the staple unit 308.

The feed members 313 are provided above the inclined surface 311a of the first alignment portion 311 and above the inclined surface 312a of the second alignment portion 312, respectively, and each of the feed members 313 has the same structure. Therefore, in the following description, the feeding member 313 corresponding to the first alignment unit 311 will be described.

Here, the details of the feeding member 313 will be described below.

As shown in FIGS. 9 and 10, the feed member 313 feeds the transfer paper P on the inclined surface 311a in the direction of the stopper 501 (FIG. 8) of the staple unit 308 (FIG. 8) by the feed roller 316 moving up and down. Has become.

The feed roller 316 has the same configuration as the pickup roller 224 and the pickup roller 227 provided in the image forming apparatus main body 200, and is connected to a roller arm 319 rotatably supported by a support shaft 315. The rotational drive of the feed roller 316 is controlled ON / OFF by a clutch mechanism, and the vertical movement of the roller arm 319 is controlled by a solenoid.

That is, the feeding roller 316 is at the standby position when it is lowered to the inclined surface 311a side (FIG. 10), and is raised by turning on the solenoid in accordance with the ingress of the transfer paper P (the state shown in FIG. 9). The transfer paper P descends at the timing when it passes below the feed roller 316, starts rotating when the clutch mechanism is turned on, and conveys the transfer paper P toward the stopper 501 (FIG. 8).

In this case, the rotation operation time of the feed roller 316, that is, the feed amount of the transfer paper P is determined by the paper detection sensor A provided on the paper transport path 301 or the paper detection sensor provided on the staple tray 303 shown in FIG. Timer control based on the detection signal of C, or detection by pushing up the paper leading end pressing lever 502 due to deflection of the transfer paper P, or detection of contact of the leading end of the transfer paper P with the stopper 501, or at the time of the first sheet insertion It learns the ON timing of the paper detection sensor C and the tray paper presence / absence sensor D provided on the staple tray 303, and controls the second and subsequent sheets by improving the accuracy of timer control from the ON timing of the paper detection sensor C. Is done.

(4) With this, in a state where the leading end of the transfer sheet P is securely in contact with the stopper 501, the transfer sheet P is held by the sheet leading end pressing levers 502 arranged on both sides of the stopper 501.

In the staple tray 303, the distance from the paper discharge roller 318 to the first feeding member 313 and the second feeding from the first feeding member 313 in order from the upstream side in the transfer paper P transport direction. The distance to the member 313 and the distance from the second feeding member 313 to the paper discharge roller 309 are set to be shorter than the minimum size length that allows staples.

押 Further, on both sides of the feed roller 316, a pressing lever 314 for pressing down the curl of the transfer sheet P on the inclined surface 311a is provided.

As shown in FIG. 9, the holding lever 314 is rotatable in the directions of arrows i and j with the rotation axis of the feed roller 316 as a fulcrum. When the feed roller 316 is located on the upper side, a roller arm 319 is provided. , The movement is restricted to a state substantially parallel to the roller arm 319. That is, the pressing lever 314 is regulated such that the movement of the roller arm 319 by the regulating member 317 is regulated so that the rotation in the direction of the arrow j can be performed only up to a predetermined position. The predetermined position is a position where the pressing lever 314 does not enter the escape path 302 formed on the staple tray 303, and is not particularly limited.

When the feed roller 316 is moving down, as shown in FIG. 10, the press lever 314 acts to press the transfer paper P on the inclined surface 311a. The pressing force of the pressing lever 314 is set so as to be rotatable by a fixed amount in the direction of pushing up the pressing lever 314 in the direction of arrow j due to the curl of the transfer paper P, and the length, weight, spring force ( It can be arbitrarily set by the power or the like.

Here, the paper transport operation in the image forming apparatus having the above configuration will be described below. In this image formation, single-sided printing for forming an image on one side will be described.

In the image forming apparatus having the above configuration, when the output to the first paper stack tray 401 is selected and the staple function and the offset function are not selected, or even when the staple function and the offset function are selected, the second paper stack tray 402 is selected. In the case of transfer paper P of a paper size corresponding to the prohibition of output to paper and the prohibition of stapling, the second switching gate 304 is rotated in the direction of arrow e (FIG. 3) to transfer the transfer paper P to the escape path 302. Further, the third switching gate 307 is rotated in the direction of arrow g (FIG. 4) to discharge the transfer paper P to the first paper stack tray 401.

Even when the first sheet stack tray 401 is selected, if a large amount of transfer paper P exceeding the allowable stacking amount of the first sheet stack tray 401 is output, the first sheet discharge unit which is the main body stack unit is used. Each switching gate is switched so that the transfer paper P is automatically discharged to the 234 or the second paper stack tray 402, and the operator is notified to the operation unit (not shown) that the output port (discharge unit) has been changed. It displays and informs, or informs that output is not possible without starting the job.

Further, when the output to the second paper stack tray 402 is selected and the offset function is selected, the transfer paper P is conveyed through the escape path 302 and rotated in the third switching gate 307 in the direction of arrow h (FIG. 4). The sheet is output to the second sheet stack tray 402 through the second sheet discharge path 306, and normal stacking and offset stacking are performed.

(4) The control of each of the switching gates uses sheet size information. As the sheet size information, the size detection information of the sheet cassette 221 and the size detection information of the manual feed tray 222 are used.

However, in the manual feed tray 222, there is also a transfer sheet P for which size detection is not performed due to paper feed of an irregular size or the like. In such a case, the sheet size is determined by obtaining the sheet length information based on the ON time of the sheet conveyance such as the pre-registration sensor. Nevertheless, there are transfer papers P having the same length but different widths. For example, there are A5 vertical feed and A4 horizontal feed. To cope with this, in view of the switching time of the second switching gate 304, the paper detection sensor A (FIG. 8) is arranged at a position separated by that distance so as not to detect the A5 width but to detect the A4 width. What should I do?

Similarly, by performing the process before the first switching gate 235, it is possible to select a sheet that is not permitted to enter the post-processing device 300. In this case, control is performed such that the first switching gate 235 is switched so as to discharge the transfer paper P to the first paper discharge unit 234 on the image forming apparatus main body 200 side.

(5) The details of the above processing flow will be described below.

First, the transfer operation of the transfer sheet P when the offset function is selected by the post-processing device 300 will be described below with reference to the flowcharts shown in FIGS. 1 to 4, 8, and 11.

First, the operator selects the offset function by the post-processing device 300 (step S1). In this case, since the printing is a one-sided printing in which an image is formed on one side of the transfer paper P, the switching gate 238 shown in FIG. 2 is fixed while rotating in the direction of arrow b.

Next, based on the main body paper size information, it is determined whether or not the paper size selected by the operator is an allowable size for output to the second paper stack tray 402 of the paper stacking unit 400 (step S2). The paper size refers to the paper stack unit 4
9 shows the size and number of transfer sheets P discharged at 00.

Here, when it is determined that the paper size is not the allowable size for output to the second paper stack tray 402, output prohibition and offset mode cancellation are performed, and the fact is displayed on a display panel (not shown). Notify the operator (step S3).

On the other hand, if it is determined in step S2 that the paper size is an allowable size for output to the second paper stack tray 402, printing is started (step S4).

Next, based on the pre-registration sensor ON time, it is determined whether or not the paper size selected by the operator is an allowable size for output to the second paper stack tray 402 of the paper stack unit 400 (step S5). The paper size indicates the size and the number of transfer papers P discharged from the paper stack unit 400.

Here, if it is determined that the paper size is the output allowable size to the second paper stack tray 402, the process proceeds to step S6, in which the first switching gate 235 is rotated in the direction of the arrow c and the second switching gate 304 is rotated. Is rotated in the direction of arrow e. That is, the transfer paper P is transported on the escape path 302 of the post-processing device 300 via the paper transport path 301.

Next, based on the pre-registration sensor ON time, it is determined whether or not the sheet size selected by the operator is an allowable size for output to the second sheet stack tray 402 of the sheet stacking unit 400 (step S7). The paper size indicates the size and the number of transfer papers P discharged from the paper stack unit 400.

If it is determined that the paper size is the output allowable size for the second paper stack tray 402, the third switching gate is rotated in the direction of arrow h (step S8). On the other hand, if it is determined that the sheet size is not the output allowable size to the second sheet stack tray 402, the process proceeds to step S12. The processing after step S12 will be described later.

Then, the transfer paper P transported on the escape path 302 is offset-stacked on the second paper stack tray 402 (Step S9). The second paper stack tray 402 moves up and down according to the amount of the transfer papers P to be stacked, and a new transfer paper P is always conveyed to the uppermost surface of the stacked transfer papers P. I have.

(4) If it is determined in step S5 that the paper size is not the output allowable size for the second paper stack tray 402, the process proceeds to step S11. This step S11 is also executed when the output of the transfer sheet P is selected in the first sheet stack tray 401 (step S10).

In the above step S11, the transferred transfer paper P is sent to the post-processing device 300 based on the ON signal of the paper detection sensor E (FIG. 24) provided before the first switching gate 235 of the image forming apparatus main body 200. It is determined whether or not the output size is acceptable. Here, if it is determined that the transfer paper P to be conveyed has the allowable size for output to the post-processing apparatus 300, the process proceeds to step S12. If not, the first switching gate 235 is moved in the direction of arrow d. (Step S15), and outputs the transfer paper P to the first paper discharge unit 234, which is the main body stack unit (Step S16).

In step S12, it is determined whether the number of output sheets is equal to or less than the allowable amount of the first sheet stack tray 401. That is, it is determined whether or not the number of output transfer sheets P is an amount that can be stacked on the first sheet stack tray 401.

If it is determined in step S12 that the amount of transfer paper P to be stacked is the allowable amount of the first paper stack tray 401, the third switching gate 307 is rotated in the direction of arrow g (step S13), and the first switching gate 307 is rotated. The transfer paper P is output to the paper stack tray 401 (step S14).

On the other hand, if it is determined in step S12 that the amount of transfer paper P to be stacked is not the allowable amount of the first paper stack tray 401, the third switching gate 307 is rotated in the direction of arrow h (step S17), and the second The transfer paper P is output to the paper stack tray 402 (Step S18).

As described above, when the offset function is selected in the post-processing apparatus 300, the first paper output unit 234, the first paper stack tray 401, the second paper stack The transfer paper P can be output to any of the trays 402.

In particular, when a large amount of transfer paper P is output at once, if the transfer paper P is a paper that can pass through the post-processing device 300, the second paper stack tray 402 is used as an output destination of the transfer paper P. If the transfer paper P is a paper that cannot pass through the post-processing device 300, the first paper discharge unit 234 is used as an output destination of the transfer paper P.

Therefore, when a large amount of transfer paper P is output at one time, the transfer paper P is not output to the first paper stack tray 401 where the allowable amount of transfer paper P that can be stacked is small. Problems such as jams in the vicinity can be eliminated.

Next, the transport operation of the transfer sheet P when the staple function is selected in the post-processing apparatus 300 will be described below with reference to the flowcharts shown in FIGS. 1 to 4, 8 and 12.

First, the operator selects the staple function of the post-processing device 300 (step S21). In this case, since the printing is a one-sided printing in which an image is formed on one side of the transfer paper P, the switching gate 238 shown in FIG. 2 is fixed while rotating in the direction of arrow b.

Next, it is determined whether or not the paper size selected by the operator is a staple allowable size based on the main body paper size information (step S22). The paper size indicates the size and the number of transfer papers P discharged from the paper stack unit 400.

If it is determined that the paper size is not the staple allowable size, the output is prohibited and the staple mode is canceled, and the operator is notified by displaying the fact on a display panel (not shown) (step S23).

On the other hand, if it is determined in step S22 that the paper size is the staple allowable size, it is determined whether the number of originals read is equal to or less than the staple allowable number (step S24). Here, if it is determined that the output transfer sheet P has the staple allowable size, printing is started (step S25). If it is determined in step S24 that the paper size is not the staple allowable size, the process proceeds to step S23.

Next, it is determined whether or not the sheet size selected by the operator is a staple allowable size based on the pre-registration sensor ON time (step S26). Here, if it is determined that the paper size is the staple allowable size, the first switching gate 235 is rotated in the direction of arrow c (step S27), and based on the time since the paper detection sensor A was turned on, It is determined whether or not the paper size selected by the operator is a staple allowable size (step S28).

If it is determined in step S28 that the paper size is the staple allowable size, the second switching gate 304 is rotated in the direction of arrow f (step S29), and the staple tray 303 is moved to a predetermined position corresponding to the paper size. After the transfer paper P is stored and aligned, it is stapled (step S30), and the transfer paper P is output to the second paper stack tray 402 (step S31).

On the other hand, if it is determined in step S28 that the paper size is not the staple allowable size, the process proceeds to step S33. The description of step S33 will be described later.

If it is determined in step S26 that the paper size selected by the operator is not the staple allowable size based on the pre-registration sensor ON time, then based on the ON signal of the paper detection sensor E (FIG. 24), It is determined whether or not the transfer paper P to be conveyed has an allowable size for output to the post-processing device 300 (step S32). Here, if it is determined that the transferred transfer paper P has an allowable size for output to the post-processing apparatus 300, the second switching gate 304 is rotated in the direction of arrow e, and the third switching gate 307 is moved in the direction of arrow g. The transfer paper P is output to the first paper stack tray 401 (step S34).

On the other hand, if it is determined in step S32 that the transfer paper P being transported is not of an allowable size for output to the post-processing device 300, the first switching gate 235 is rotated in the direction of arrow d (step S35), and the main body stacking section is rotated. The transfer paper P is output to the first paper discharge unit 234 (step S36).

As described above, in the post-processing apparatus 300, even when the staple function is selected, the first paper discharge unit 234, the first paper stack tray 401, the second paper stack Since any of the trays 402 is automatically selected, it is possible to prevent a jam or the like caused by an incorrect operation performed by the operator.

In the image forming apparatus having the above-described configuration, the post-processing device 300 and the sheet stacking unit 400 are detachable, so that the user can detach it as needed. When the post-processing device 300 and the paper stack unit 400 are removed, the document reading unit 100 is directly mounted on the upper part of the image forming apparatus main body 200 as shown in FIG. In this case, the discharge unit is only the first discharge unit 234 formed in the space below the document reading unit 100.

Further, in the image forming apparatus having the above configuration, as shown in FIG. 1, the staple unit 308 in the post-processing device 300 is provided in a space formed below the document reading unit 100, but is not limited thereto. For example, as shown in FIG. 14, a staple unit 308 may be provided in the paper stack unit 400. In this case, the sheet stacking section 400 has not only a sheet stacking function but also a sheet staple function.

In the image forming apparatus having the above-described configuration, the description has been made on the assumption that the escape path 302 and the staple tray 303 are driven by different driving sources. A case where the feed roller 316 which is a driving roller among the rollers 310 is also used will be described. For convenience of description, members having the same functions as those in FIGS. 8 to 10 are denoted by the same reference numerals, and description thereof will be omitted.

For example, as shown in FIG. 15, the central paper guide 302a forming the lower surface of the escape path 302 is formed with an opening 302b such that a part thereof can protrude when the feeding roller 316 moves upward. Further, the escape path 302 is provided with a pressure roller 331 that presses the feed roller 316 protruding from the central paper guide 302 a from above the escape path 302. The opening 302b is formed smaller than the diameter of the pressure roller 331.

The central paper guide 302a is a common member that forms the lower surface member of the escape path 302 and also forms the upper surface member of the staple tray 303.

開口 An opening 302d through which the pressure roller 331 can penetrate from above is formed in the upper paper guide 302c facing the central paper guide 302a of the escape path 302. Therefore, the pressure roller 331 is urged downward by an elastic member such as a spring, and when the feed roller 316 moves to the inclined surface 311a side as shown in FIG. Through the opening 302d of the upper paper guide 302c, the movement thereof is regulated by the opening 302b of the central paper guide 302a.

Therefore, when the transfer paper P is transported along the escape path 302, as shown in FIG. 15, a part of the feed roller 316 moves so as to protrude from the opening 302b of the central paper guide 302a and contact the pressure roller 331. The transfer paper P is conveyed by guiding the transfer paper P to a nip formed by the feed roller 316 and the pressure roller 331.

On the other hand, when the transfer paper P is transported on the staple tray 303, as shown in FIG. 16, the feed roller 316 moves so as to contact the inclined surface 311a. At this time, the transfer paper P placed on the inclined surface 311a is conveyed by the rotational force of the feed roller 316 while being pressed by the pressing lever 314 moved downward in conjunction with the movement of the feed roller 316.

That is, as shown in FIG. 16, in a state where the feed roller 316 is lowered, the pressure roller 331 is pressed downward by the urging force, and stops at the opening 302b of the central paper guide 302a as a stopper. I have.

When the transfer paper P conveys the escape path 302, the pressing roller 331 is pushed upward by the feed roller 316 moved upward by turning on the solenoid, and rotated by turning on the clutch mechanism, as shown in FIG. The rotation starts following the feeding roller 316. At this time, the pressing force by the feed roller 316 to the pressure roller 331 that generates the transfer force of the transfer sheet P is set to a strength that does not cause the transfer sheet P to slip, and the transfer sheet P can be reliably transferred. It has become.

When the transfer paper P is transported on the staple tray 303, the feeding roller 316 is in a standby position when it comes into contact with the inclined surface 311a as shown in FIG. Then, the feed roller 316 moves upward when the solenoid is turned on in accordance with the entry of the transfer paper P, moves down when the transfer paper P passes below the feed roller 316, and rotates when the clutch mechanism is turned on. The transfer paper P is conveyed toward a stopper 501 of a staple unit 308 (not shown).

In this case, the rotation operation time of the feed roller 316, that is, the feed amount of the transfer paper P is determined by the paper detection sensor A provided on the paper transport path 301 or the paper detection sensor provided on the staple tray 303 shown in FIG. Timer control based on the detection signal of C, detection by pushing up the paper leading end pressing lever 502 due to the transfer paper P bending, detection of contact of the leading end of the transfer paper P with the stopper 501, or paper at the time of the first sheet insertion The ON timing of the detection sensor C and the tray paper presence / absence sensor D provided on the staple tray 303 is learned, and the second and subsequent sheets are controlled by improving the accuracy of timer control from the ON timing of the paper detection sensor C. You. As a result, in a state where the leading end of the transfer sheet P is securely in contact with the stopper 501, the transfer sheet P is held by the sheet leading end pressing levers 502 arranged on both sides of the stopper 501.

When the feeding roller 316 is used for both the escape path 302 and the staple tray 303, the feeding roller 316 serving as a driving roller has a transport force for transporting the transfer sheet P in the escape path 302, and the transfer paper P for the staple tray 303. The rotation is controlled so as to be stronger than the conveying force for conveying P.

In other words, the transfer force of the transfer sheet P in the escape path 302 is preferably as strong as possible in order to reliably transfer the transfer sheet P, but the transfer force of the transfer sheet P in the staple tray 303 is preferably as weak as possible. This is because the leading end of the transfer paper P is always brought into contact with the stopper 501 of the staple unit 308, and if the transfer paper P is transported with a strong transport force, a paper jam may occur. is there.

Therefore, when the transfer sheet P is conveyed on the staple tray 303, the conveyance force of the transfer sheet P by the feed roller 316 is set to the minimum size necessary for conveying the transfer sheet P. The transport force in this case is set to a size that allows the transfer paper P to move while sliding on the transfer paper P or the guide plate stocked on the inclined surface 311a for stapling, for example. As a result, the transfer paper P is not damaged or damaged by the transfer of the transfer paper P.

Further, even if the feeding amount control of the transfer paper P is disturbed due to noise such as static electricity, the transfer roller 316 and the transfer roller 316 are transferred even if a load is applied to the transfer paper P with the leading end of the transfer paper P reaching the stopper 501 of the staple unit 308. Since the paper S slips between the paper P and the paper P, jam due to excessive feeding of the paper P and breakage of the paper P can be prevented, and the leading ends of the paper P can be surely aligned.

Here, the driving mechanism of the feed roller 316 will be described below with reference to FIGS.

As shown in FIG. 17, the drive mechanism includes a drive source 332 and a drive transmission unit 333 for transmitting the drive force of the drive source 332 to the feed roller 316.

The drive source 332 has a gear 332a that can be driven forward and reverse. The drive transmission unit 333 includes a first gear 333a meshing with the gear 332a, a second gear 333b meshing with the first gear 333a, and a third gear 333c meshing with the second gear 333b. And a fourth gear 333d meshing with the third gear 333c, and a fifth gear 333e meshing with the fourth gear 333d.

The first gear 333a is attached to a support shaft 315 which is a rotation fulcrum of the roller arm 319. The fifth gear 333e is connected to the feed roller 316 at a support shaft 320 which is a rotation fulcrum of the feed roller 316. It is provided so as to rotate integrally. Further, the second gear 333b to the fourth gear 333d are supported by a support member (not shown) provided to rotate in conjunction with the roller arm 319.

That is, the driving force of the driving source 332 is transmitted from the gear 332a to the first gear 333a of the drive transmission unit 333, and is sequentially transmitted from the second gear 333b to the third gear 333c, the fourth gear 333d, and the fifth gear 333e. It is transmitted and rotates the feed roller 316.

Also, a drive transmission unit 334 as shown in FIG. 18 may be used instead of the drive transmission unit 333 as the drive mechanism. The drive transmission unit 334 is supported by a support shaft 315, and is supported by a gear 335 meshing with the gear 332 a of the drive source 332 and a support shaft 315 common to the gear 335. The first pulley 336 is interlocked with the rotation, the second pulley 337 is supported by the support shaft 320 of the feed roller 316, and the belt 338 is stretched over the first pulley 336 and the second pulley 337. I have.

That is, the driving force of the driving source 332 is transmitted to the gear 335 meshing with the gear 332a, the first pulley 336 interlocked with the gear 335 rotates, and the rotational force of the first pulley 336 is reduced. It is transmitted to the second pulley 337 by the belt 338 and rotated.

In the image forming apparatus having the above-described configuration, a claw-shaped switching gate is used to switch the transfer path of the transfer paper P. However, the present invention is not limited to this. For example, the transfer is performed using a three-joint roller as described below. The transport path of the paper P may be switched.

Here, instead of the second switching gate 304 for switching the transfer paper P in the post-processing apparatus 300 shown in FIG. 1 from the paper transport path 301 to the escape path 302 or the staple tray 303, switching is made of three continuous rollers shown in FIG. The case where the means 350 is used will be described.

As shown in FIG. 19, the switching unit 350 includes a first roller 351, a second roller 352, and a third roller 353, which are connected to each other at a branch point between the escape path 302 and the staple tray 303 so as to be rotatable. The transfer paper P discharged from the nip portion formed between the first roller 351 and the second roller 352 is discharged to the escape path 302, and the second roller 352 and the third roller The transfer paper P discharged from the nip formed with the roller 353 is discharged to the staple tray 303.

The second roller 352 is a driving roller, and the driving force is transmitted to the first roller 351 and the third roller 353. Further, a rod-shaped first gate member 354 is provided on the support shaft 352 a of the second roller 352 toward the sheet transport path 301 so as to interlock with the rotation of the second roller 352.

One end of the first gate member 354 is pivotally supported by a support shaft 352a of the second roller 352, and an opening 354a is formed at the other end, and a rod-like shape is formed in the opening 354a via the support shaft 355. A second gate member 356 is provided rotatably.

One end of the second gate member 356 is rotatably supported by the support shaft 355 at the opening 354a of the first gate member 354, and is rotatably supported by a fixed shaft 357 fixed to the apparatus main body at substantially the center. Have been. The opening 354a of the first gate member 354 is a play portion when the first gate member 354 and the second gate member 356 are driven in conjunction with each other.

The first gate member 354 and the second gate member 356 are provided on both side surfaces of the second roller 352, as shown in FIGS. The minimum interval is set smaller than the minimum size width of the transfer paper P conveyed to the post-processing apparatus 300. Thereby, the transfer paper P can be branched without fail.

The first gate member 354 is supported by the support shaft 352a of the second roller 352 with an appropriate frictional force. Accordingly, when the second roller 352 rotates, the first gate member 354 rotates in the same direction as the second roller 352 due to the frictional force between the first gate member 354 and the support shaft 352a. In addition, between the first gate member 354 and the support shaft 352a, the first gate member 354 idles when a certain force or more is applied thereto.

Further, the fixed shaft 357 is formed so as to be substantially parallel to the support shaft 352a of the second roller 352, and the first gate member 354 is supported when the second roller 352 rotates in the direction of the solid arrow. The first gate member 354 is rotated upward by the frictional force with the shaft 352a, and the second gate member 356 is moved downward with respect to the fixed shaft 357 so that the end on the upstream side in the transfer paper P transport direction is downward. The sheet rotates toward the lower side of the sheet transport path 301 (the state shown by the solid line in FIG. 19). This state is referred to as a first position. In the first position, while the second roller 352 is rotating in the direction of the solid line arrow, the gap between the first gate member 354 and the support shaft 352a is kept idle.

In the first position, the end of the second gate member 356 on the upstream side in the transfer sheet P transfer direction is located below and is in contact with the lower surface of the sheet transfer path 301. The transfer paper P conveyed 301 is guided by the second gate member 356 and the first gate member 354, and is conveyed between the first roller 351 and the second roller 352. Since the first roller 351 and the second roller 352 are rotating in the direction of the solid arrow, the transfer paper P transported to the nip formed between the first roller 351 and the second roller 352 is After passing through the nip portion, the sheet is conveyed to the escape path 302.

That is, when it is desired to transfer the transfer paper P to the escape path 302, the second roller 352 is moved in the direction indicated by the solid arrow so that the first gate member 354 and the second gate member 356 are maintained at the first position. What is necessary is just to control so that it may rotate.

On the other hand, when the second roller 352 rotates in the direction of the dashed arrow, the first gate member 354 rotates downward due to the frictional force with the support shaft 352a, and the second gate 354 rotates downward due to the rotation of the first gate member 354. The member 356 rotates upward around the fixed shaft 357 in the transfer paper P transport direction and comes into contact with the upper surface of the paper transport path 301 (the state shown by the broken line in FIG. 19). This state is referred to as a second position. In the second position, while the second roller 352 is rotating in the direction of the dashed arrow, the gap between the first gate member 354 and the support shaft 352a is kept idle.

In the second position, the end of the second gate member 356 on the upstream side in the transfer sheet P transfer direction is located above and is in contact with the upper surface of the sheet transfer path 301. The transfer paper P conveyed by 301 is guided by the second gate member 356 and the first gate member 354, and is conveyed between the second roller 352 and the third roller 353. Since the second roller 352 and the third roller 353 are rotating in the direction of the dashed arrow, the transfer paper P transported to the nip formed between the second roller 352 and the third roller 353 is The paper is conveyed to the staple tray 303 through the nip.

That is, when the transfer paper P is to be conveyed to the staple tray 303, the second roller 352 is moved in the direction indicated by the dashed arrow so that the first gate member 354 and the second gate member 356 are maintained at the second position. What is necessary is just to control so that it may rotate.

In the switching unit 350, the transfer paper P is branched using two bar-shaped gate members. However, the present invention is not limited to this, and the switching unit 360 as shown in FIG. Even when the switching unit 370 is used, the transfer paper P can be similarly branched and conveyed.

As shown in FIG. 21, the switching means 360 includes a rotatable gear-shaped first gate member 361 and a rod-shaped second gate member 362 supported by a rotation shaft 361a of the first gate member 361. It is configured. The second gate member 362 is axially supported with a certain frictional force with respect to the rotation shaft 361a, and rotates with the rotation of the first gate member 361. The second gate member 362 is formed in such a length that the leading end on the upstream side in the transfer paper P transport direction can contact the upper or lower surface of the paper transport path 301 by the rotation of the second gate member 362. I have.

A gear 363 is coaxially and integrally provided on the second roller 352, and the gear 363 meshes with the first gate member 361. Thus, the rotational force of the second roller 352 is transmitted from the gear 363 to the first gate member 361.

That is, when the second roller 352 rotates in the direction of the solid arrow, the first gate member 361 rotates in the direction of the solid arrow in conjunction with the second roller 352, so that the upstream of the second gate member 362 in the transfer paper P transport direction. The end on the side moves downward, and the end comes into contact with the lower surface of the sheet transport path 301. This state is referred to as a first position. Therefore, while the second roller 352 is rotating, the second gate member 362 idles with respect to the rotation shaft 361a, and the first position is maintained.

On the other hand, when the second roller 352 rotates in the direction of the dashed arrow, the first gate member 361 rotates in the direction of the dashed arrow in conjunction with the second roller 352, so that the upstream of the second gate member 362 in the transfer paper P transport direction. The end on the side moves upward, and the end comes into contact with the upper surface of the sheet transport path 301. This state is referred to as a second position. Therefore, while the second roller 352 is rotating, the second gate member 362 idles with respect to the rotation shaft 361a, and the second position is maintained.

In the above-described configuration, when the transfer paper P is transported to the escape path 302, the second roller 352 is rotated in the direction of the solid line arrow so that the end of the second gate member 362 on the upstream side in the transfer paper P transport direction is the paper. The first position is brought into contact with the lower surface of the transport path 301. As a result, the transfer paper P conveyed along the paper conveyance path 301 is guided between the first roller 351 and the second roller 352 by the second gate member 362, and the transfer between the first roller 351 and the second roller 352 is performed. It is sent out to the escape path 302 from a nip portion formed between them.

On the other hand, when the transfer paper P is transported to the staple tray 303, the second roller 352 is rotated in the direction of the dashed arrow so that the end of the second gate member 362 on the upstream side in the transport paper P transport direction is the paper transport path 301. To the second position in contact with the upper surface of the. As a result, the transfer paper P transported along the paper transport path 301 is guided between the second roller 352 and the third roller 353 by the second gate member 362, and the transfer between the second roller 352 and the third roller 353 is performed. The paper is sent out to the staple tray 303 from the nip formed therebetween.

In the switching means 360, the gear 363 integrally provided with the second roller 352 is provided to drive the first gate member 361. However, the switching means shown in FIGS. As in 370, the rotation of the second roller 352 may be transmitted by directly contacting the second roller 352.

As shown in FIGS. 22A and 22B, the first gate member 371 is formed of a roller-shaped member, and the rotation of the second roller 352 is transmitted by contacting the second roller 352. I have. A rod-shaped second gate member 372 is pivotally supported at one end of the rotation shaft 371a of the first gate member 371.

The second gate member 372 is supported with a predetermined frictional force with respect to the rotation shaft 371a, and rotates in conjunction with the rotation of the first gate member 371. The second gate member 372 is formed to have a length such that the leading end on the upstream side in the transfer paper P transport direction can contact the upper or lower surface of the paper transport path 301 by the rotation of the second gate member 372. I have.

In the above configuration, when the transfer paper P is transported to the escape path 302, the second roller 352 is rotated in the direction of the solid line arrow so that the end of the second gate member 372 on the upstream side in the transfer paper P transport direction is the paper. The first position is brought into contact with the lower surface of the transport path 301. As a result, the transfer paper P conveyed along the paper conveyance path 301 is guided between the first roller 351 and the second roller 352 by the second gate member 372, and the transfer between the first roller 351 and the second roller 352 is performed. It is sent out to the escape path 302 from a nip portion formed between them.

On the other hand, when the transfer paper P is transported to the staple tray 303, the second roller 352 is rotated in the direction of the dashed arrow, and the upstream end of the second gate member 372 in the transfer paper P transport direction is moved to the paper transport path 301. To the second position in contact with the upper surface of the. As a result, the transfer paper P conveyed along the paper conveyance path 301 is guided by the second gate member 372 between the second roller 352 and the third roller 353, and the transfer between the second roller 352 and the third roller 353 is performed. The paper is sent out to the staple tray 303 from the nip formed therebetween.

As described above, when the above-described three-joint roller is used as a means for branching the transfer paper P, the means for driving a member for switching the transfer direction of the transfer paper P is provided by the three-joint roller. One drive roller is used. That is, the driving means for the means for branching the transfer paper P is shared. Thereby, the size of the device can be reduced.

In the following, the transfer direction of the transfer sheet P is switched using the above-described three-joint roller, and the transfer sheet P of a size for which staple processing such as postcard is generally prohibited is not erroneously transferred to the staple tray 303. The paper transport system for this purpose will be described with reference to FIG.

As shown in FIG. 23, the paper transport system is applied to an image forming apparatus capable of transporting the transfer paper P around a switching unit 350 for branching the transfer paper P in the vertical direction. For example, immediately after the fixing of the transfer sheet P, the transfer sheet P is branched into two transfer paths (a first discharge transfer path 391 and a second discharge transfer path 392) in a process of transferring the transfer sheet P from below to above. . In FIG. 23, the first discharge conveyance path 391 is connected to the escape path 302 shown in FIG. 1, and the second discharge conveyance path 392 is connected to the staple tray 303 shown in FIG.

As shown in FIG. 23, the paper transport system includes four transport paths (a first transport path 381, a second transport path 382, a first transport path 391, and a second transport path 392) before reaching the first discharge transport path 392. The third transport path 383 and the fourth transport path 384) are provided.

The first transport path 381 is formed between the first transport roller 385 that transports the transfer paper P immediately after fixing and the switching unit 350. Note that the first transport roller 385 may also serve as a fixing roller. In this manner, by providing the first transport roller 385 with a function as a fixing roller, the number of components in the paper transport system can be reduced, so that the configuration of the apparatus can be simplified.

The second transport path 382 is formed between the switching unit 350 and the second transport roller 386 that transports the transfer sheet P to the second discharge transport path 392. The second transport path 382 is a transport path that normally transports the transfer paper P discharged from the nip between the second roller 352 and the third roller 353 of the switching unit 350 to the staple tray 303.

The third transport path 383 is formed between the switching unit 350 and a third transport roller 387 that transports the transfer sheet P to the first discharge transport path 391. A fourth transport roller 388 is further provided between the switching unit 350 and the third transport roller 387 to ensure transport of the transfer sheet P to the first discharge transport path 391. The third transport path 383 is a transport path that normally transports the transfer paper P discharged from the nip between the first roller 351 and the second roller 352 of the switching unit 350 to the escape path 302.

The fourth transport path 384 extends from the first transport path 381 of the switching unit 350 to the third transport roller 387, bypassing the third transport path 383. The fourth transport path 384 is provided with a fifth transport roller 389 and a sixth transport roller 390 in order to reliably transport the transfer paper P.

In the paper transport system having the above configuration, in the second transport path 382, the distance from the nip between the second roller 352 and the third roller 353 of the switching unit 350 to the nip of the second transport roller 386 is a staple. The tray 303 is set to a paper size that allows staples (hereinafter, referred to as a staple allowable size).

Accordingly, the leading end of the stapleable transfer paper P is chucked by the second transport roller 386 before being completely discharged from between the second roller 352 and the third roller 353. Thus, the transfer paper P can be reliably sent to the second discharge conveyance path 392.

Further, by forming the second transport path 382 substantially perpendicular to the installation surface of the image forming apparatus, the transfer paper P having the staple allowable size is chucked by the second transport roller 386. The transfer paper P smaller than the transfer paper P is not chucked by the second transport roller 386, and falls to the switching means 350 side by its own weight. This is because, if the transfer paper P smaller than the staple allowable size is not completely discharged from between the second roller 352 and the third roller 353, the leading end of the transfer paper P can be chucked to the nip portion of the second transport roller 386. Because it does not become.

(4) Accordingly, it is possible to determine whether or not the transfer sheet P can be stapled only by transporting the transfer sheet P to the second transport path 382.

Therefore, in the second conveyance path 382, a paper size sensor or the like can be obtained simply by adjusting the distance between the nip between the second roller 352 and the third roller 353 of the switching unit 350 and the nip of the second conveyance roller 386. Can be used to detect the transfer paper P that can be stapled.

Accordingly, with a simple configuration, the stapleable transfer paper P can be reliably sent to the staple tray 303, but the staple-inhibited transfer paper P can be prevented from being sent to the staple tray 303. As a result, it is possible to prevent various troubles (jam and the like) caused by feeding the staple-inhibited transfer paper P to the staple tray 303.

When the transfer paper P passing through the nip between the second roller 352 and the third roller 353 of the switching means 350 is smaller than the staple allowable size, the transfer paper P is again moved by the second roller due to its own weight. 352 and the third roller 353, but the second roller 352 and the third roller 353 rotate in the direction of the arrow P, so that they move along the surface of the second roller 352 and The ink is guided between the roller 351 and the second roller 352, and is discharged to the fourth conveyance path 384 from this distance.

At this time, since the first gate member 354 and the second gate member 356 are driven so as to discharge the transfer paper P from between the second roller 352 and the third roller 353, the second gate member 356 is It is at the position indicated by the broken line in FIG.

Accordingly, the transfer sheet P discharged from between the first roller 351 and the second roller 352 is reliably transported to the fourth transport path 384 without returning to the first transport path 381.

Here, the transport operation of the transfer paper P in the paper transport system having the above configuration will be described below with reference to FIG.

First, the transfer paper P that has passed through the fixing roller (not shown) is introduced into the first transport path 381 by the first transport roller 385, and the switching unit 350 switches either the second transport path 382 or the third transport path 383. To the transport path. At this time, if the transfer paper P needs to be stapled, it branches to the second transport path 382, and if the transfer paper P does not need to be stapled, it branches to the third transport path 383.

The transfer paper P that needs to be stapled has its leading end passed through the nip between the third roller 353 and the second roller 352 until its trailing end passes through the second conveyance path 382 downstream of the second conveyance path 382. It is chucked by the roller 386. That is, the transfer paper P conveyed to the staple tray 303 via the second discharge conveyance path 392 is transferred to the nip portion between the second roller 352 and the third roller 353 and the second conveyance roller 386 in the second conveyance path 382. And the nip portion is chucked at the same time.

Here, when the operator operates the staple-inhibited transfer paper P, for example, a postcard, by mistake, to perform the stapling process, the transfer paper Pa discharged from the first transport roller 385 becomes the second roller 352 and the third roller 352. The paper passes through the nip between the rollers 353 and is discharged to the second conveyance path 382 like the transfer paper Pb.

However, the distance between the nip portion between the second roller 352 and the third roller 353 and the nip portion of the second transport roller 386 is set to the minimum value of the staple allowable paper size. In the case of a transfer sheet P such as a sheet, that is, a postcard, even if the transfer sheet P is discharged to the second conveyance path 382 from between the second roller 352 and the third roller 353, its leading end does not reach the nip portion of the second conveyance roller 386. Become. Moreover, since the second transport path 382 is formed substantially perpendicular to the installation surface of the apparatus, the transfer paper Pb falls due to its own weight, and its rear end is rotated in the rotation direction of the second roller 352 (arrow P). Direction), and becomes like transfer paper Pe. Thereafter, the transfer paper Pe is guided from the nip portion between the first roller 351 and the second roller 352 to the fourth transport path 384, is transported to the nip portion of the third transport roller 387, and is discharged to the first discharge transport path. 391. That is, the transfer paper Pe is chucked from the nip between the first roller 351 and the second roller 352 to the nip of the sixth transport roller 390 in a state like the transfer paper Pf, and is discharged from the nip. Then, after being chucked at the nip portion of the fifth transport roller 389 like the transfer paper Pg, the paper is discharged from the nip portion, chucked at the nip portion of the third transport roller 387, and is discharged to the first discharge transport path 391. And supplied to the escape path 302.

On the other hand, when the transfer paper Pc is supplied to the escape path 302, the transfer paper Pc is guided to the nip portion between the first roller 351 and the second roller 352 by the switching means 350, and from the nip portion to the third transport path 383. The sheet is ejected, the leading end thereof is chucked by the fourth conveyance roller 388 (transfer paper Pd), and is guided to the first ejection conveyance path 391 via the third conveyance roller 387.

As described above, according to the paper transport system having the above configuration, even if the staple-inhibited transfer paper P (paper smaller than the staple allowable size) is erroneously transported to the second transport path 382, the transfer paper P is discharged from the switching unit 350. The transferred transfer paper P is not chucked by the second transport roller 386 but is automatically transported to the fourth transport path 384 and guided to the first discharge transport path 391 leading to the escape path 302.

(4) This prevents the staple-inhibited transfer paper P from being erroneously guided to the staple tray 303, thereby preventing the staple tray 303 from being jammed due to unnecessary paper conveyance.

The length of the transport path (second transport path 382) for guiding to the staple tray 303 (the distance from the nip between the second roller 352 and the third roller 353 to the nip of the second transport roller 386). Is set to the staple allowable size, and it is determined whether or not the transfer sheet P is staple prohibited. Therefore, it is not necessary to provide a sensor or the like as a separate member for determining the sheet size. Therefore, the structure of the paper transport system can be simplified, and the manufacturing cost of the entire apparatus can be reduced.

The copying function includes a one-sided printing function for forming an image on one side of the transfer sheet P and a two-sided printing function for forming an image on both sides of the transfer sheet P. In the above description, the single-sided printing function has been mainly described. However, the case where the double-sided printing function is realized in the image forming apparatus having the above configuration will be described below. As described above, in order to realize the double-sided printing function, a means for reversely transporting the transfer paper P in the image forming apparatus, that is, a switchback mechanism is required.

For example, as shown in FIG. 24, it is conceivable to provide a reversing conveyance unit 600 for reversing the transfer paper P on the staple tray 303.

The reversing and conveying means 600 has a re-feed belt 601 that can be rotated forward and reverse along the sheet conveying direction on the surface of the staple tray 303 on which the transfer paper P is placed, and rotates the re-feed belt 601 in the direction of the arrow. By doing so, the transfer paper P temporarily placed on the staple tray 303 is discharged to the reverse conveyance path 237 in the image forming apparatus main body 200. That is, the re-feed belt 601 is provided at a position where the rear end of the transfer paper P placed on the staple tray 303 slightly overlaps.

As shown in FIG. 25, the reversing and conveying means 600 contacts the end of the transfer paper P placed on the staple tray 303 on the staple processing direction side and sends the transfer paper P in the reversal conveyance direction. The transport plate 602, a paper pressing lever 603 that presses the transfer paper P placed on the staple tray 303 from the upper surface side, and the transfer paper P provided on the end in the reverse transport direction of the transfer paper P, And a separating member 604 for sending out one sheet at a time to the reverse conveyance path.

The transport plate 602 is a wall that stands perpendicular to the transfer paper P mounting surface of the staple tray 303, is movable in the transport direction of the transfer paper P, and comes into contact with an end of the transfer paper P. The transfer paper P is sent out by moving the transfer paper P in the direction in which the paper is to be transported. Further, the transport plate 602 functions as a stopper for the transfer paper P on which single-sided printing has been completed during double-sided printing.

In addition, the transport plate 602 normally stands by at the upstream end of the staple tray 303 in the paper transport direction (the state shown in FIG. 24) so as not to hinder the transport of the transfer paper P during single-sided printing. I have.

The paper pressing lever 603 has a shaft portion 603a that is supported at the lower surface of the escape path 302 at one end, not shown, and the other end presses the transfer paper P placed on the staple tray 303 from above. It is made of a member (integrally formed body) made up of a holding portion 603b, and is provided rotatably around the shaft portion 603a.

用紙 The paper holding lever 603 is driven and controlled by a solenoid (not shown). That is, by controlling the driving of the solenoid, when the transfer paper P is transported onto the staple tray 303, the pressing portion 603b moves upward, and the transfer paper P is placed on the staple tray 303. Then, the pressing portion 603b moves downward so as to press the transfer paper P from above.

The separating member 604 is a substantially L-shaped member provided on the rear end side of the staple tray 303, and the interval between the lowermost portion and the re-feed belt 601 is approximately the thickness of one transfer sheet P. To prevent double feed (double conveyance) when the transfer paper P is conveyed reversely.

Here, the transfer operation of the transfer sheet P in the image forming apparatus provided with the reverse transfer means 600 having the above configuration will be described below with reference to FIGS. 24 and 25.

At the time of double-sided printing, the first switching gate 235 located after passing through the fixing of the apparatus main body is moved in the direction of arrow c, and the second switching gate 304 is moved in the direction of arrow e to transfer the transfer paper P after fixing to the paper transport path 301. From the staple tray 303.

At this time, at the time of the stapling operation, the transport plate 602 waiting at a predetermined position on the staple tray 303 moves to the downstream of the sheet length plus about 2 mm based on the sheet length information and stands by.

The transport plate 602 serves as a stopper for the leading end of the transfer paper P sent to the staple tray 303 during double-sided printing, and performs the function of aligning the paper in the paper length direction as a double-sided printing intermediate tray.

The alignment member 505 used in the stapling process is used for the alignment in the sheet width direction. Here, the alignment member 505 is used instead of the fixed wall 509 shown in FIG. Thus, the transfer paper P is aligned from both sides in the width direction. More specifically, the alignment members 505 and 505 are controlled by a timer from the detection of the sheet detection sensor A provided before the switching gate 304 so that the alignment members 505 and 505 are moved from both sides in the width direction of the transfer sheet P toward the center reference of the transfer sheet P. It is driven to push.

The above operation is performed on the set number of transfer sheets P, and the sheet bundle on which single-sided printing has been completed is stored on the staple tray 303 in an aligned state.

After the alignment of the set number of final pages is completed, the rear end of the sheet bundle stored on the staple tray 303 is pressed from above by the sheet pressing lever 603 driven and controlled by the solenoid.

In this manner, while the sheet bundle is pressed down from above by the sheet pressing lever 603, the refeed belt 601 is driven in the direction of the arrow, and only the lowermost transfer sheet P of the sheet bundle is conveyed. At this time, double feeding of the transfer paper P is prevented by the separating member 604.

(4) The transfer sheet P sent out by the re-feed belt 601 is sent to the reversing conveyance path 237 of the image forming apparatus main body 200 with the rear end of the sheet leading. Then, the transfer paper P is chucked by the first transport roller 237a in the reverse transport path 237, and the driving of the re-feed belt 601 is stopped. That is, the drive of the re-feed belt 601 is stopped by the timer control until the transfer paper P to be reversely transported is chucked by the transport roller 237a, and the paper pressing lever 603 is also moved upward. This re-feed operation is continued until the set number of sheets ends at the same timing as the sheet interval at the time of single-sided printing.

The re-transferred transfer paper P is guided to the registration roller 229 via the reverse conveyance path 237, and the registration roller 229 aligns the transfer paper P with the toner image on the photoconductor 211 of the image forming unit 210. After that, printing is performed on the side (back side) on which an image is not formed by flowing as in the case of single-sided printing, and is conveyed to any one of the first paper discharge unit 234 serving as the main body paper stack unit, the escape path 302, and the staple tray 303. Is done.

According to the above configuration, it is not necessary to separately provide an intermediate tray used for double-sided printing, so that the configuration of the transport system of the apparatus main body can be simplified, and the apparatus can be reduced in size and cost.

In the above description, the staple tray 303 is used as an intermediate tray during double-sided printing, and the copying method in which the transfer paper P printed on one side is temporarily stored in the staple tray 303 and then printed on the other side has been described. However, the present invention is not limited to this. For example, a copying method in which transfer paper P is printed on both sides one by one is also possible. In this case, the transfer paper P on which the single-sided printing has been performed is conveyed onto the staple tray 303, and then the transfer paper P may be immediately reversed and conveyed.

When the staple tray 303 is used as an intermediate tray for double-sided printing as described above, double-sided printing cannot be performed due to interruption during staple processing. Therefore, it is conceivable to use the escape path 302 as an intermediate tray for double-sided printing so that double-sided printing can be performed even in such a case.

That is, when double-sided printing is performed by interruption during the stapling operation, the second switching gate 304 is moved in the direction of arrow e. As a result, the transfer paper P to be printed on both sides is conveyed to the escape path 302. At this time, based on the paper length information, the first switching gate is moved in the direction of arrow d when the trailing edge of the transfer paper P at that time passes the first switching gate 235, and the rotation of the transport roller 310 near the escape path 302 is rotated. Reverse the direction. As a result, the transfer paper P is sent to the reverse conveyance path 237, which is a conveyance path for double-sided printing, and is printed on both sides. The transfer paper P on which double-sided printing has been completed is discharged via the escape path 302.

When double-sided printing is performed by interruption during staple processing as described above, by using the escape path 302 as an intermediate tray, the stackability of the transfer paper P already stored in the staple tray 303 for staple processing can be prevented. Thus, switchback for double-sided printing can be performed.

In other words, since the switchback mechanism is provided in the escape path 302 and the staple tray 303, the switchback mechanism of the escape path 302 is used when double-sided printing is performed by interruption while the staple tray 303 is being used. Will be done. Thus, double-sided printing can be performed without disturbing the stackability of the sheets on the staple tray 303.

In addition, the switchback can be performed without damaging the transfer sheet P to be switched back and ensuring the positional accuracy of the transfer sheet P.

When the switchback mechanism of the staple tray 303 is used, the staple tray 303 can be used as an intermediate tray, so that a predetermined number of single-sided printing sheets can be stocked. By switching back the single-sided printing paper stocked for a predetermined number of sheets, double-sided printing is completed. Therefore, the efficiency of double-sided printing can be improved.

Further, as described above, the transport plate 602 is provided on the staple tray 303 as an alignment member for aligning the end of the transfer paper P opposite to the post-processing direction so as to be movable in the paper transport direction. By doing so, the alignment member as a post-processing function can be used as an alignment member when used as an intermediate tray during double-sided printing, and as a result, members required for the switchback mechanism can be reduced. It is possible to reduce the size and cost of the entire apparatus.

In the image forming apparatus having the above-described configuration, as shown in FIG. 1, the escape path 302 is provided with a plurality of transport rollers in a transport path, and drives the transport rollers to move the transfer paper P through the transport path. It is designed to be transported. This transport path is formed of a paper transport guide plate completely separated from the staple tray 303, and the transfer paper P supplied to the paper transport guide plate is discharged to the outside of the apparatus without being guided to the staple tray 303. It has become.

Therefore, separate drive rollers are required for the escape path 302 and the staple tray 303.

Therefore, instead of the escape path 302, an escape path 700 as shown in FIG.

The escape path 700 has a configuration in which a plurality of paper transport members 701, each of which can be driven independently, are arranged side by side in the paper transport direction. The sheet conveying member 701 includes a sheet conveying belt 702 and a pair of rollers 703 that stretch the sheet conveying belt 702.

Among the rollers 703, the roller 703 disposed on the opposite side in the paper transport direction is provided in a state of being in contact with the drive roller 704 via the paper transport belt 702 and in a state where the rotation shaft is fixed to the apparatus main body. ing. Therefore, the roller 703 is driven by the rotation of the drive roller 704, and the paper transport belt 702 stretched around the roller 703 is driven to rotate.

On the other hand, among the rollers 703, the roller 703 disposed on the paper transport direction side is rotatably provided around the rotation axis of the other roller 703 as a fulcrum. As a result, the sheet conveying member 701 rotates from the state illustrated in FIG. 30 to the staple tray 303 side as illustrated in FIGS. 31 and 32 around the rotation axis of the roller 703 on the opposite side of the sheet conveying direction. It is supposed to.

(4) In the escape path 700 having the above configuration, the transfer paper P is chucked and transported between the paper transport belt 702 of the paper transport member 701 and the drive roller 704.

As shown in FIG. 26, a driven roller 705 is provided between the paper transport members 701 to contact the respective paper transport belts 702 and follow the rotation of the paper transport belts 702. Thus, by driving only the driving roller 704 on the upstream side in the sheet conveying direction, the sheet conveying belts 702 of all the sheet conveying members 701 can be rotationally driven.

As described above, since the paper transport member 701 is rotatable about the rotation axis of one roller 703 as described above, the escape path 700 is rotated by rotating the paper transport member 701. The transfer paper P to be conveyed can be sent to the staple tray 303 on the way. In this case, as shown in FIG. 30, among the paper transport members 701 at the home position, some of the paper transport members 701 are arranged such that the paper transport belt 702 contacts the staple tray 303 as shown in FIG. As shown in FIG. 32, the paper feed member 701 is rotated from the home position to a predetermined angle α.

That is, the sheet conveying member 701 at the position where the transfer of the transfer sheet P from the escape path 700 to the staple tray 303 is started to rotate as shown in FIG. 32, and escape is performed by utilizing the inclination of the sheet conveying member 701. The transfer paper P conveyed on the path 700 is sent to the staple tray 303, and the paper conveyance member 701 at the position for transferring the transfer paper P on the staple tray 303 rotates as shown in FIG. The transfer paper P is transported by sandwiching the transfer paper P at a contact portion between the paper transport belt 702 and the staple tray 303 of the paper transport member 701. The number of rotations of the paper transport member 701 is determined according to the paper size.

That is, when the B5 size transfer paper P is fed from the escape path 700 to the staple tray 303, as shown in FIG. 27, the second paper transport member 701 from the end in the paper transport direction rotates. State. When the A4 size transfer paper P is sent from the escape path 700 to the staple tray 303, as shown in FIG. 28, the third paper transport member 701 from the end in the paper transport direction is rotated. State. Further, when the A3-size transfer paper P is sent from the escape path 700 to the staple tray 303, as shown in FIG. 29, all of the five paper transport members 701 are in a rotated state.

Regardless of the size of the transfer paper P sent to the staple tray 303 according to the paper size as described above, the leading end of the transfer paper P is aligned by the stopper 706 provided on the downstream side of the staple tray 303 in the paper transport direction. You. As a result, even if the transfer paper P having a different paper size is sent to the staple tray 303, the next transfer paper P is always conveyed to the upper surface of the transfer paper P placed first. Can be transported smoothly.

According to the escape path 700 having the above-described configuration, since the transfer unit of the transfer paper P provided in the escape path 700 also serves as the transfer unit for transferring the staple tray 303, the escape path 302 and the staple tray 303 are provided. And the number of transport rollers is greatly reduced as compared with the case where drive rollers for transporting the transfer paper P are separately provided in the escape path 302 and the staple tray 303, as in the case of a structure in which the transfer paper P is completely separated. can do.

As shown in FIG. 32, the sheet transporting member 701 located at the most upstream side in the sheet transporting direction among the sheet transporting members 701 rotating to feed the transfer sheet P is positioned at a predetermined position from the transporting surface of the escape path 700 as shown in FIG. , In this case, an angle smaller than 90 °. This makes it possible to smoothly transfer the transfer paper P that has been transported on the escape path 700 to the staple tray 303.

The size and the number of the paper transporting members 701 are determined so that the size of the transfer paper P from the B5 size to the size of the A3 size transfer paper P are sent from the escape path 700 to the staple tray 303. The size and arrangement of the sheet conveying member 701 are not limited, and the size and arrangement of the sheet conveying member 701 can be such that transfer paper P of a size that can be stapled and other than the above-described sheet size can be fed into the staple tray 303. The number may be determined.

Here, a staple tray 303 for transporting the transfer paper P on which staple processing is performed and an escape path 302 for transporting the transfer paper P on which staple processing is not performed are separately provided. The mechanism will be described below with reference to FIGS.

FIG. 33 is a perspective view showing only the post-processing device 300, and FIG. 34 is an explanatory diagram schematically showing a cross section of the post-processing device 300 shown in FIG. FIGS. 35A to 35C are explanatory diagrams showing a jam clearing operation.

In the post-processing apparatus 300, as shown in FIGS. 35B and 35C, the central paper guide 302a of the escape path 302 and the transport guide 303b of the staple tray 303 are respectively orthogonal to the paper transport direction, that is, It is configured to open to the operation surface side of the device.

As shown in FIG. 34, the central paper guide 302a and the transport guide 303b are supported by a rear frame member 651, a front frame member 652, and an upper plate 653 of the post-processing device 300, which constitute the post-processing device 300. . That is, the central paper guide 302a is supported with one end connected to the rear frame member 651 via the movable member 654 and the other end mounted on the upper surface 652a of the front frame member 652. . One end of the transport guide 303b is connected to the rear frame member 651 via the movable member 655, and is also connected to the rear surface by the movable member 656. Further, the other end of the transport guide 303b is fixed to a front frame member 652.

The movable member 654 has one end fixed to the back frame member 651 and the other end fixed to the central paper guide 302a. The central paper guide 302a can be moved by removing the support by the front frame member 652. It is designed to pivot downward with 654 as a fulcrum.

Similarly, the movable member 655 has one end fixed to the rear frame member 651 and the other end fixed to the transport guide 303b, and the transport guide 303b is supported by the movable member 655 together with the front frame member 652. It is designed to pivot downward. The movable member 656 has one end fixed to the back frame member 651 and the other end fixed to a contact member 657 provided below the transport guide 303b. The contact member 657 is in contact with the lower surface of the transport guide 303b and normally supports the transport guide 303b. When the transport guide 303b is opened, the contact member 657 is detached from the transport guide 303b. Has become.

フ ッ ク Further, a hook-shaped lever 658 is provided on the upper surface of the front frame member 652, and the tip of the lever 658 is engaged with the upper plate 653. That is, when the locked state between the lever 658 and the upper surface plate 653 is released, the central paper guide 302a and the transport guide 303b simultaneously rotate downward, and the operation surface side of the post-processing device 300 is opened. State.

The jam processing in the post-processing device 300 having the above configuration will be described below with reference to FIGS. It is assumed that the jam detection is performed based on the transfer timing of the transfer sheet P without disposing a jam detection sensor in the post-processing apparatus 300.

First, when a jam detection sensor or the like notifies the occurrence of a jam in the post-processing device 300, the operator releases the locked state between the lever 658 and the upper plate 653. As a result, as shown in FIG. 35 (a), after the jam (transfer paper P ') occurs in the escape path 302 and the staple tray 303, the post-processing device 300 operates as shown in FIG. 35 (b). Opened on the surface side. For convenience of explanation, it is assumed that a jam occurs in both the escape path 302 and the staple tray 303.

Then, first, the transfer paper P ′ on the central paper guide 302a is removed from the post-processing device 300 in the open state, and the central paper guide 302a is lifted up as shown in FIG. Remove the paper P '.

(4) Finally, the transport guide 303b is lifted, and the lever 658 is locked to the upper plate 653, thereby completing the jam processing.

In the above description, the case where the jam processing has occurred in both the escape path 302 and the staple tray 303 has been described. However, the same applies to the case where the jam has occurred in either the escape path 302 or the staple tray 303. Jam processing can be performed by an operation.

As described above, in the post-processing apparatus 300, the escape path 302 and the staple tray 303 are configured to be opened in a direction orthogonal to the sheet conveyance direction. Even if the transferred transfer sheet P is placed on the transfer sheet P, jam processing can be performed without disturbing the aligned transfer sheet P only by removing the transfer sheet P in a jam state generated thereon. Therefore, immediately after the jam processing, the print request can be processed continuously.

In the above description, the jam is detected based on the transfer timing of the transfer sheet P and the jam processing is performed without providing the jam detection sensor in the post-processing apparatus 300. The case where the jam detection sensor is attached will be described.

As shown in FIG. 36, a jam detection mechanism including a paper detection sensor 800 disposed between the central paper guide 302a of the escape path 302 and the transport guide 303a of the staple tray 303 is used for the above-described jam detection. .

As shown in FIGS. 37A and 37B, the paper detection sensor 800 includes an optical sensor 801 and two large and small arms 802 and 803 that block the optical path of the optical sensor 801. The arm 802 and the arm 803 are rotatably supported by a common support shaft 804.

The optical sensor 801 has one light emitting unit 801a and a light receiving unit 801b, and the end 802a of the arm 802 and the end 803a of the arm 803 are disposed between the light emitting unit 801a and the light receiving unit 801b. Are located. That is, the rotation of the arms 802 and 803 blocks the optical path of the optical sensor 801 and limits the amount of light incident on the light receiving unit 801b.

The end 802b of the arm 802 opposite to the end 802a is formed so as to protrude from the central paper guide 302a as shown in FIG. As a result, when the transfer paper P is transported through the central paper guide 302a, the transfer paper P comes into contact with the end 802b of the arm 802 and rotates the arm 802 in the direction of the arrow. The amount of light incident on the light receiving unit 801b is changed.

On the other hand, an end 803b of the arm 803 opposite to the end 803a is formed so as to be close to the transport guide 303b, and when the transfer paper P is transported through the transport guide 303b, the transfer paper P The arm 803 is rotated in the direction of the arrow by contacting the end 803b, and the amount of light incident on the light receiving portion 801b of the optical sensor 801 is changed by the end 803a.

By the way, the balance of the center of gravity of the arm 802 and the balance of the center of gravity of the arm 803 are designed to be different.

In other words, the arm 802 has a center of gravity in the direction from the support shaft 804 serving as a fulcrum to the optical path side of the optical sensor 801, and when the transfer paper P is not in the escape path 302, as shown in FIG. With the paper guide 302a protruding and the end 802a having no effect on the amount of light incident on the light receiving portion 801b of the optical sensor 801, the transfer paper P is being conveyed to the escape path 302 or the transfer paper P is transferred. When the paper P is jammed, as shown in FIG. 39, the end 802b is pushed downward by the transfer paper P and rotated toward the staple tray 303, and the end 802a blocks the optical path of the optical sensor 801. Become.

On the other hand, when the arm 803 has a center of gravity in the direction of the transport guide 303b from the support shaft 804, which is a fulcrum, and when there is no transfer paper P in the staple tray 303, as shown in FIG. At a distance, the end 803a does not affect the amount of light incident on the light receiving portion 801b of the optical sensor 801, and the transfer paper P is being conveyed to the staple tray 303 or the transfer paper P At the time of a jam, as shown in FIG. 41, the end 803b is pushed upward by the transfer paper P and rotated toward the escape path 302, and the end 803a blocks the optical path of the optical sensor 801.

As described above, when the end portion 802a of the arm 802 blocks the optical path of the optical sensor 801 for a predetermined time or more, the operation panel or the like is notified that a jam has occurred in the escape path 302, and the optical sensor 801 If the time during which the optical path is interrupted is within a predetermined time, the fact that the transfer paper P is being transported through the escape path 302 is notified to an operation panel or the like. The case of the arm 803 is the same as that of the arm 802.

{Circle around (2)} As described above, the paper detection sensor 800 having the above configuration also serves as a paper detection sensor in both the escape path 302 and the staple tray 303 and also serves as a jam detection sensor. Accordingly, the jam processing in the post-processing device 300 can be appropriately performed, and it is not necessary to provide a separate space for disposing a sensor for jam processing. As a result, the transfer path of the transfer paper P can be further simplified.

画像 The image forming apparatus of the present invention can be implemented in various configurations as described below.

That is, according to the image forming apparatus of the present invention, in the image forming apparatus in which the sheet post-processing device can be additionally mounted on the main body having the first paper discharge unit below the scanner, the paper transport path leading to the first paper discharge unit is provided. A paper conveying path of a paper post-processing device provided above the main body and below the scanner is connected to a branch that is branched into two in the main body and does not face the first paper discharge unit. The paper transport path is further branched into two, and post-processing of the paper is performed in one of the two paths. The paper transport path in which the post-processing is not performed reaches the second paper discharge unit provided on the side of the main body. The paper transport path on which the processing is performed is configured to reach a third paper discharge unit provided on the side of the main body.

According to the above configuration, the paper transport path in the main body is branched into two, and the paper transport path of the paper post-processing device is connected to the branch that is not directed to the first paper discharge unit. The unit can be used without being blocked by the sheet post-processing device. Further, the sheet conveyance path of the sheet post-processing device is branched into two, and the corresponding second and third discharge units are provided, so that the total number of discharge units is three.

Therefore, when it is desired to sort and output sheets to different paper output units for each of a plurality of functions of the image forming apparatus, a number corresponding to three typical functions such as a copy function, a print function, and a facsimile function. Can be secured without sacrificing the first paper discharge unit, and the space performance and convenience are improved.

Further, of the two paper transport paths branched in the paper post-processing apparatus, the one that reaches the third paper discharge section is used for post-processing of paper. In addition, it is not necessary to perform complicated operation control in one sheet conveyance path unlike the related art. Further, the transport rollers whose conditions are optimized for post-processing and the transport rollers optimized when post-processing is not performed can be arranged in separate paper transport paths, which hinders paper transport. Not even.

According to another image forming apparatus of the present invention, a sheet conveyance path leading to a second sheet discharge unit is branched so as to communicate with a third sheet discharge unit, and sheets are discharged to any of the first, second, and third sheet discharge units. This is a configuration in which the user can select whether to do so.

According to the above configuration, it is possible to select a paper discharge unit to be used according to the convenience of the user. In the case where a sheet that is not subjected to post-processing is discharged to the third sheet discharge unit, the sheet can be discharged to the third sheet discharge unit using a sheet conveyance path that does not perform post-processing in the sheet post-processing apparatus. Therefore, the third paper discharge unit can be selected even when post-processing is not performed.

In still another image forming apparatus according to the present invention, it is possible to select a paper discharge unit for each function, and for a function in which a third paper discharge unit is selected and no post-processing is performed, an internal paper post-processing apparatus is used. In this configuration, the sheet is discharged to the third sheet discharge unit from a sheet conveyance path that does not perform post-processing.

According to the configuration described above, it is possible to sort sheets output according to functions such as a copy function, a print function, and a facsimile function. Further, it is not necessary to consider the presence or absence of post-processing for the function to which the third paper discharge unit is assigned.

(6) Still another image forming apparatus according to the present invention has a configuration in which selection of a function is set using a display panel, and the setting is stored in a memory until the setting is changed.

According to the above configuration, the selection operation is facilitated, and it is not necessary to perform the setting every time the image forming apparatus is used.

In still another image forming apparatus of the present invention, when performing post-processing of a sheet, the sheet is discharged to the third sheet discharge unit regardless of the user's selection.

According to the above configuration, the post-processing of the sheet is correctly performed even if the user makes an erroneous selection of the discharge unit.

According to still another image forming apparatus of the present invention, when a sheet of a type for which post-processing is prohibited is conveyed during post-processing of a sheet, the sheet is discharged using a sheet conveying path that does not perform the post-processing. It is a configuration that is performed.

According to the above configuration, if the post-processing is performed on the paper for which the post-processing is prohibited, there is a possibility that the conveyance of the paper may be disturbed, so that this can be prevented.

(7) Still another image forming apparatus according to the present invention has a configuration in which a gate for selecting a branch destination of the paper transport path is provided at each branch point of the paper transport path.

According to the above configuration, it is possible to easily form a path until the paper is discharged to a target paper discharge unit.

Still another image forming apparatus according to the present invention includes a document reading means (scanner), a printing means for printing image information, a paper feeding means for containing and feeding paper, a cassette means, and a paper discharging means for discharging printed paper. In the image forming apparatus having the U-shaped image forming apparatus, the discharging unit is disposed below the document reading unit, above the sheet feeding unit and the cassette unit, and further on a side surface of the printing unit. A paper post-processing transport path for substantially horizontally transporting the paper is disposed in the paper discharge unit, and the post-processing transport path has a paper alignment member, and the transported paper is aligned after being aligned. In this configuration, the sheet bundle is post-processed by post-processing (staple) means.

According to the above configuration, by arranging the sheet post-processing device by effectively using the space portion (above the sheet discharging portion) of the U-shaped image forming apparatus, the apparatus can be made compact, and the occupied space can be reduced. Can be reduced.

Further, since the sheet alignment position and the post-processing (staple) position are the same, post-processing can be performed without deforming the aligned sheet bundle, and a printed matter with the sheet bundle arranged can be provided to the user.

Still another image forming apparatus according to the present invention includes a document reading unit (scanner), a printing unit for printing image information, a paper feeding unit for storing and feeding paper, a cassette unit, and a paper discharging unit for discharging printed paper. An image forming apparatus having a printing paper post-processing means between the paper discharging means and a storage means for storing printing paper, wherein the post-processing means is a space formed with respect to the image forming apparatus, The post-processing of the printing paper is performed by the means.

According to the above configuration, it is not necessary to dispose the image forming apparatus on the side surface of the image forming apparatus, so that the apparatus space can be effectively used and a compact design can be achieved.

Still another image forming apparatus according to the present invention includes a document reading unit (scanner), a printing unit for printing image information, a paper feeding unit for storing and feeding paper, a cassette unit, and a paper discharging unit for discharging printed paper. In an image forming apparatus having a printing paper post-processing means between the paper discharging means and a storage means for storing paper, the post-processing means is disposed substantially horizontally with respect to the image forming apparatus, This is a configuration having two transport paths.

According to the above configuration, the size of the device attached to the side surface of the image forming apparatus can be made compact, and the space occupied by the entire device can be reduced.

According to still another image forming apparatus of the present invention, the first transport path among the two transport paths transports printing paper to a first paper stack tray and a second paper stack tray.

According to the above configuration, the functions of the paper stack unit, such as the output of special paper and small-size paper, the output of a large amount, and the offset function, can be fully utilized.

According to still another image forming apparatus of the present invention, of the two transport paths, the second transport path is configured to staple print paper on a second paper stack tray and then transport the staple print paper.

According to the above configuration, by configuring the conveyance path exclusively for staples, it is easy to configure the alignment member and the drive system of its power source.

According to still another image forming apparatus of the present invention, the staple unit is attached to the same member as the stopper and the fixed wall, and the staple unit is disposed outside the width of the main body.

According to the above configuration, it is possible to improve the positional accuracy of the stapling with respect to the sheet and to improve the appearance quality of the sheet bundle after the stapling.

According to still another image forming apparatus of the present invention, the printing paper conveyed in the second conveyance path may be, depending on the type of printing, a rear end portion of the printing paper in one of a plurality of recesses arranged in the conveyance path. Is stored, the alignment of the leading edge of the paper and the alignment of pages of a plurality of printing papers can be easily performed.

According to the above configuration, the next sheet always comes on the stacked sheets without the need for a dedicated pressing member or control.

さ ら に Still another image forming apparatus of the present invention is configured to have a width shifting mechanism for alignment in the above-described substantially horizontal post-processing apparatus.

According to the above configuration, the staple unit can be fixed at a predetermined position by aligning the paper to improve the quality of the staple bundle and by shifting the paper to the staple position.

According to still another image forming apparatus of the present invention, the bundle of printing sheets stapled by the stapling unit is a sheet conveying member disposed on a staple tray section of a post-processing apparatus, the second stack tray and the staple tray section. And a fourth sheet discharging roller disposed between the second sheet stack tray and the second sheet stack tray.

According to the above configuration, the sheets can be discharged without damaging the bundled sheets.

According to still another image forming apparatus of the present invention, the post-processing apparatus has a gate unit for branching a sheet into a first conveyance path and a second conveyance path inside the post-processing apparatus.

According to the above configuration, sorting can be performed according to whether or not the staple function is selected.

According to still another image forming apparatus of the present invention, the gate means can be switched based on paper size information from a main body paper feeding unit and a result obtained by a paper length and width detecting means passing through the main body. It is.

According to the above configuration, it is possible to sort according to each permitted sheet.

According to still another image forming apparatus of the present invention, the rotation and rotation of the drive roller to the staple path are detected by detecting that the leading edge of the sheet has been discharged from the sheet discharging unit of the apparatus, and then the leading edge of the sheet is conveyed to the rotating roller. This is a configuration that is performed after.

According to the above configuration, when the leading end of the sheet is conveyed to the driving roller portion, the gap between the driving roller and the contact member is sufficiently wide, and even if the sheet is curled, the conveying operation can be smoothly performed without the leading end hitting the roller. I can do it.

According to still another image forming apparatus of the present invention, the rotation angle or the rotation time of the driving roller to the staple path is set until the leading edge of the sheet reaches the staple leading edge stop mechanism.

According to the above configuration, after the leading end of the sheet reaches the staple leading end stop mechanism, the rotation of the drive roller is stopped or the drive roller is rotated to the escape path, thereby preventing jamming due to excessive feeding of the sheet and damage to the sheet. It becomes possible.

In still another image forming apparatus of the present invention, the staple driving roller has a conveying force set such that the leading end of the paper reaches the staple leading end stop mechanism, and when a load is applied to the paper, the paper slips between the paper and the roller. Configuration.

According to the above configuration, the staple drive roller has a conveying force set such that the leading end of the paper reaches the staple leading end stop mechanism, and when a load is applied to the paper, the paper slips between the paper and the roller. Therefore, the leading edge of the sheet can be surely aligned without causing jam due to excessive feeding of the sheet and damage to the sheet.

According to still another image forming apparatus of the present invention, a rotating roller is connected to a gear that rotates in conjunction with a rotating arm from a gear attached to a rotating fulcrum to transmit a rotational force. It is.

According to the above configuration, since the rotating roller is connected to the gear that rotates in conjunction with the rotating arm from the gear attached to the rotating fulcrum, the rotational force is transmitted, so that the arm rotates. Thus, the driving force is smoothly transmitted without a change in the gear pitch.

(6) Still another image forming apparatus according to the present invention is configured such that a rotating roller is connected to a rotating shaft by a belt or a gear or a pulley attached to a rotating fulcrum to transmit a rotating force.

According to the above configuration, since the rotating roller is connected to the gear or the pulley attached to the rotation fulcrum by the belt and the rotational force is transmitted, the pitch of the gear or the pulley changes due to the arm rotation. In the case of gear connection, if the rotating arm is long, the number of gears will be large or the gear will be large, but if the belt is connected, it can be handled only by changing the belt length Thus, the number of parts can be reduced and the size can be reduced.

According to still another image forming apparatus of the present invention, the transporting force of the rotated roller is greater in the escape path than in the staple path.

According to the above configuration, at the time of staple path conveyance, the conveyance paper moves while sliding on the paper or the guide plate stocked for staple, but the conveyance force of the drive roller at the time of staple (the pressure contact force between the roller and the paper). By reducing the size, it is possible to prevent the paper from being scratched or damaged.

According to still another image forming apparatus of the present invention, in the print sheet post-processing means, the paper jam in the escape conveyance path is disposed on the side of the apparatus from the detection of the conveyance of the sheet by the printing means of the image forming apparatus. Even when the paper arrives at the paper discharge section, it is determined that the paper has jammed in the escape conveyance path when the paper has not arrived.

According to the above configuration, at the time of printing request, when performing discharge using the escape transport path without requesting post-processing, a detection mechanism for detecting the passage and retention of paper in the transport path becomes unnecessary. .

In still another image forming apparatus of the present invention, in the printing paper post-processing means, after the paper jam in the post-processing conveyance path is selected by the printing request, the post-processing of the printing paper is selected. Even if the job is completed, it is determined that the paper has jammed in the post-processing conveyance path when the paper does not arrive even when the paper arrives at the paper discharge unit arranged on the side of the apparatus. .

According to the above configuration, when a post-processing is requested at the time of a print request, it is determined that the paper is not discharged even when one job is completed and the next job is started. No more deposition.

A first image forming apparatus according to the present invention includes: a document reading unit that reads image information of a document; an image forming unit that forms an image on a sheet based on image information of the document read by the document reading unit; An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including an image forming unit and performing post-processing such as alignment and stapling of an image-formed sheet; A space surrounded by the outer peripheral wall of the apparatus body is formed as a discharge unit for discharging the sheet on which an image is formed by the image forming unit, and the sheet is placed between the document reading unit and the space. A relay transport path for transporting the sheet from the image forming section to the sheet post-processing section is formed.

In addition, a second image forming apparatus of the present invention includes a document reading unit that reads image information of a document, and an image forming unit that forms an image on a sheet based on the image information of the document read by the document reading unit. An image forming apparatus provided with a paper post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing such as alignment and stapling of an image-formed sheet. A space surrounded by an outer peripheral wall of the apparatus body is formed as a discharge unit for discharging the sheet on which the image is formed by the image forming unit, and the sheet is formed on the back of the document reading unit. A relay transport path for transporting the sheet from the forming section to the sheet post-processing section is formed.

Further, a third image forming apparatus of the present invention includes a document reading unit that reads image information of a document, and an image forming unit that forms an image on a sheet based on the image information of the document read by the document reading unit. An image forming apparatus provided with a paper post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing such as alignment and stapling of an image-formed sheet. A document space on which a space surrounded by an outer peripheral wall of the apparatus main body is formed as a discharge unit for discharging a sheet on which an image is formed by the image forming unit; A relay conveyance path for conveying a sheet from the image forming section to the sheet post-processing section is formed on the opposite side.

In any of the above-described first to third image forming apparatuses, the relay conveying path for conveying the sheet from the image forming unit to the sheet post-processing apparatus is a space surrounded by the document reading unit and the outer peripheral wall of the apparatus main body. Therefore, a relay conveyance path is formed above a discharge unit from which a sheet not conveyed from the apparatus main body to the sheet post-processing apparatus is discharged.

Accordingly, as in the configuration of the image forming apparatus disclosed in Literature 1 and Literature 2, that is, a configuration in which a sheet not conveyed from the apparatus main body to the sheet post-processing device is discharged onto the upper surface of the relay conveyance path, a jam occurs in the relay conveyance path. If this occurs, the paper will not be discharged onto the upper surface of the relay conveyance path, so even if paper remains on the discharge unit that discharges paper that is not conveyed from the apparatus main body to the paper post-processing device, the paper will not be removed. Jam processing can be performed.

Therefore, in the relay conveyance path for conveying the sheet formed in the apparatus main body to the sheet post-processing apparatus, when a problem such as a paper jam occurs, the jam can be cleared quickly and easily, thereby improving the maintainability of the apparatus. Can be improved.

上 記 The relay conveyance path can be used for various applications as described below.

For example, in order to solve the above-mentioned problem, a fourth image forming apparatus of the present invention accommodates a sheet on which an image is formed on one side by the image forming unit and forms an image on a non-image-formed side of the sheet. For this purpose, a switchback mechanism for transporting the sheet to the image forming unit again is provided.

(4) This eliminates the need to separately provide a member having a switchback function necessary for double-sided printing on the apparatus main body side, thereby enabling the apparatus to be downsized.

In the fifth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the relay conveyance path is formed in a direction perpendicular to a sheet conveyance direction and at an end opposite to a surface operated by an operator of the apparatus. It is characterized in that it is provided so as to be openable downward with a fulcrum as a fulcrum.

(4) In the case where a sheet is jammed in the relay conveyance path, that is, when a jam occurs, the jam conveyance can be easily performed by opening the relay conveyance path on the operation surface side of the operator.

Further, in order to solve the above-mentioned problem, the sixth image forming apparatus of the present invention is provided with a jam detecting means for detecting that a sheet is jammed in the relay conveyance path. It is characterized by having.

According to a seventh image forming apparatus of the present invention, in order to solve the above-mentioned problem, the relay conveyance path is unitized so as to be detachable from the apparatus main body.

Thus, when the sheet post-processing unit is not used, the relay conveyance path can be removed, and maintenance can be performed by removing the relay conveyance path, thereby improving the maintainability of the entire apparatus. .

By the way, when a sheet post-processing device for performing post-processing such as stapling is mounted in the image forming apparatus, the result is as shown in FIG. 43 and FIG.

画像 In the image forming apparatus shown in FIG. 43, a post-processing device 50 is provided on an extension of the paper transport path 22. In the post-processing device 50, a paper stack tray 51 for stacking the paper transported from the paper transport path 22 is provided at an inclination almost perpendicular to the installation surface of the device. Therefore, in the post-processing device 50, the conveyed sheet is dropped on the sheet stack tray 51 by its own weight and aligned, and staple processing is performed in this state.

On the other hand, in the image forming apparatus shown in FIG. 44, the post-processing device 60 is provided on an extension of the paper transport path 22. In the post-processing device 60, a paper stack tray 61 for stacking the paper transported from the paper transport path 22 is provided at an inclination almost parallel to the installation surface of the device. Therefore, in the post-processing device 60, the conveyed sheets are aligned in a substantially horizontal state, and staple processing is performed in this state.

However, in the image forming apparatus shown in FIG. 43, since the sheet stack tray 51 of the post-processing device 50 is inclined substantially perpendicularly to the installation surface of the device, the installation area of the post-processing device 50 can be reduced to some extent. However, there is a problem that the post-processing device 50 becomes large in the height direction because the paper is aligned in the vertical direction.

In the image forming apparatus shown in FIG. 44, the sheet stack tray 61 of the post-processing device 60 is substantially parallel to the installation surface of the device. 43 can be made lower than that of the post-processing device 50 shown in FIG. 43, but since the installation area of the post-processing device 60 becomes large, there arises a problem that the installation area of the entire device becomes large.

Further, in any of the image forming apparatuses shown in FIGS. 43 and 44, the transport path for transporting the paper to the post-processing devices 50 and 60 uses the paper transport path 22 for discharging the paper to the discharging unit 40. When the post-processing devices 50 and 60 are mounted as described above, there arises a problem that the discharge unit 40 cannot be used.

課題 The above problem is solved in the following eighth image forming apparatus of the present invention and thereafter.

That is, in order to solve the above-described problems, an eighth image forming apparatus according to the present invention includes a document reading unit that reads image information of a document, and a paper reading unit based on the image information of the document read by the document reading unit. And an image forming unit for forming an image on the image forming unit. The image forming unit is disposed below the document reading unit, and serves as a discharging unit for discharging a sheet on which an image is formed by the image forming unit. In the image forming apparatus in which the space is formed, a paper post-processing unit is provided between the document reading unit and the space to perform post-processing such as alignment and stapling of the image-formed paper in a substantially horizontal state. It is characterized by having.

According to the above configuration, since the paper post-processing unit is provided between the document reading unit and the space unit, a space for paper post-processing is formed on the installation surface of the image forming apparatus. become. Accordingly, the installation area of the image forming apparatus having the sheet post-processing unit can be reduced, so that the degree of freedom for installing the image forming apparatus is increased.

Further, since the sheet post-processing unit performs post-processing such as alignment and stapling of the image-formed sheet in a substantially horizontal state, post-processing such as sheet alignment and stapling is performed at the same position. It can be carried out. This eliminates deformation and misalignment of the sheet bundle that occurs when the aligned sheet bundle is conveyed to the staple position, and ensures that post-processing such as stapling is performed in a state where the sheet bundle is aligned.

According to a ninth image forming apparatus of the present invention, in order to solve the above-described problem, a sheet discharging unit for discharging a sheet post-processed by the sheet post-processing unit is provided separately from the space. It is characterized by having.

According to the above configuration, the post-processed paper and the non-post-processed paper can be discharged to separate paper discharge units, so that the post-processed paper and the non-post-processed paper are completely separated. Can be. This eliminates the necessity of a sorting operation such as a case where the post-processed paper and the non-post-processed paper are discharged to the same paper output unit, thereby improving the work efficiency in the case of performing the operation in the image forming apparatus. .

According to a tenth image forming apparatus of the present invention, in order to solve the above-described problems, the paper post-processing unit includes a paper tray on which the paper on which the image is formed by the image forming unit is placed, and a paper tray on the paper tray. A staple unit for aligning the sheets placed on the paper tray and performing stapling. The staple unit is provided at the end of the sheet in the conveyance direction when aligning the sheets placed on the paper tray. It is characterized in that it is mounted on the same member as a stopper for abutting and aligning the paper and a fixed wall for abutting in a direction orthogonal to the transport direction of the paper and aligning the paper.

According to the above configuration, the stapling unit includes a stopper for abutting the end of the sheet in the sheet conveying direction and aligning the sheet when aligning the sheet placed on the sheet tray; The stopper and the fixed wall can move integrally with each other because they are attached to the same member as the fixed wall for abutting in the direction perpendicular to the direction to align the sheets.

(4) As a result, the position of the stapling process with respect to the sheet and the stapling process can be performed quickly and reliably, and as a result, the appearance quality of the sheet bundle after the stapling process can be improved.

According to an eleventh image forming apparatus of the present invention, in order to solve the above-described problems, the sheet post-processing section includes a sheet tray on which the sheet on which the image is formed by the image forming section is placed; A staple unit for aligning and stapling the paper placed on the paper tray, and abutting the paper on a fixed wall in a direction perpendicular to the paper transport direction, and aligning the aligned paper on the paper tray. It is characterized in that a width shifting mechanism for shifting the bundle to the staple position by the staple unit is provided.

According to the above configuration, the paper tray is provided with a width shifting mechanism for bringing the sheets into contact with the fixed wall in a direction orthogonal to the sheet conveying direction and for shifting the aligned sheet bundle to the staple position. Accordingly, the alignment of the sheets on the sheet tray and the alignment of the aligned sheet bundle to the staple position can be reliably performed.

(4) As a result, the sheet bundle is shifted to the staple position, so that it is not necessary to move the staple unit toward the aligned sheet bundle.

Therefore, stapling can be performed while the stapling unit is fixed at a predetermined position. As a result, stapling of the sheet bundle can be performed quickly and reliably. Can be improved.

According to a twelfth image forming apparatus of the present invention, in order to solve the above-described problem, a plurality of concave portions into which a rear end portion of a sheet in a sheet conveying direction is formed are formed in the sheet tray in accordance with a sheet size. It is characterized by:

According to the above configuration, the rear end of the sheet conveyed to the sheet tray in the sheet conveyance direction enters the recess formed according to the sheet size, and the sheets are stacked according to the sheet size. There is no need for a dedicated holding member or control means for the paper conveyed to each paper size. Thereby, the configuration on the paper tray can be simplified.

In order to solve the above-mentioned problems, a thirteenth image forming apparatus according to the present invention includes a first paper transport unit for transporting paper from the image forming unit to the paper post-processing unit, The unit includes a second paper transport path for transporting the paper not subjected to post-processing, a third paper transport path for transporting the paper for post-processing, and a transport direction of the paper passing through the first paper transport path. Gate means for switching to either the second paper transport path or the third paper transport path is provided.

According to the above configuration, the paper post-processing section is provided with the second paper transport path for transporting the paper not subjected to post-processing and the third paper transport path for transporting the paper for which post-processing is performed. Thus, the sheet not subjected to the post-processing and the sheet subjected to the post-processing can be transported separately, so that the sheet can be sorted according to the presence or absence of the post-processing. For example, by separately providing a discharge unit that communicates with each transport path, it is possible to reliably perform sorting according to the presence or absence of post-processing of paper.

According to a fourteenth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the gate unit can be switched according to sheet size information and a sheet length and a sheet width passing through the inside of the image forming apparatus main body. It is characterized by.

According to the configuration described above, the gate unit is switched according to the sheet size information and the length and width of the sheet passing through the image forming apparatus main body, so that the gate unit is connected to the second sheet transport path according to the size of the sheet. The paper can be transported by switching to the third paper transport path. For example, even if the paper size is smaller than the permissible staple size and the staple processing is selected, that is, even if the operator selects the staple processing despite using the staple prohibited paper. Since the apparatus body automatically switches the conveyance path to a conveyance path corresponding to the sheet size and conveys the sheet, it is possible to prevent the staple-inhibited sheet from being erroneously sent to the third sheet conveyance path.

As described above, the paper can be reliably fed to the transport path according to the paper size, and thus a jam caused by transport of the transport-prohibited paper, for example, staple-prohibited paper, to the third transport path can be eliminated. . Therefore, the reliability of the device can be greatly improved.

According to a fifteenth image forming apparatus of the present invention, there is provided a document reading section for reading image information of a document, and an image forming apparatus on a sheet based on image information of the document read by the document reading section. An image forming unit that forms the image, a first paper discharging unit that is provided below the document reading unit, and that discharges the paper on which the image is formed by the image forming unit, and a first paper discharging unit that transfers the paper from the image forming unit to the first paper discharging unit. A first paper transport path for transporting the paper, a paper post-processing unit for performing post-processing such as stapling on the paper on which the image is formed by the image forming unit, the document reading unit and the first paper discharging unit And is branched into two from the first paper transport path. The second paper discharge unit and the third paper discharge unit formed on the side surface of the apparatus body separately from the first paper discharge unit. A second paper transport path and a third paper transport path for guiding paper are provided. A sheet not subjected to post-processing is discharged to the second sheet discharging section through the second sheet conveying path, while a sheet post-processed by the sheet post-processing section is outputted to the third sheet discharging section. Is discharged through the third paper transport path.

According to the above configuration, the discharge destination of the sheet on which the image is formed by the image forming unit is the first discharge unit to the third discharge unit, and each discharge unit can be classified and used according to the function. . For example, when the image forming apparatus is a multifunction device capable of executing a plurality of functions such as a copier function, a facsimile function, and a print function, the first discharge unit is used as a discharge unit for discharging a sheet on which an image is formed by the copy function. The second discharge unit is used as a discharge unit that discharges a sheet on which an image is formed by the FAX function, and the third discharge unit is used as a discharge unit that discharges a sheet on which an image is formed by the print function. Accordingly, it is not necessary to perform a paper sorting operation for each function, such as when the paper on which an image is formed is discharged to the same discharge unit.

Further, in the sheet post-processing unit, the sheet that is not post-processed and the sheet that is to be post-processed convey on different conveyance paths (the second conveyance path and the third conveyance path). Transport rollers can be arranged in each transport path. As a result, there is no need to perform operation control in a complicated mechanism as in the case of transporting a sheet that is not post-processed and a sheet that is to be post-processed by the same transport path.

According to a sixteenth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the first to third paper discharge units can be selected for each function.

According to the above configuration, the first to third paper discharge units are operated by the user to discharge paper on which images are formed by various functions such as a copy function, a fax function, and a print function. The discharge unit can be arbitrarily set for each function. Thus, a function desired by the user can be assigned to each discharge unit for each user, and the convenience of the apparatus can be improved.

According to a seventeenth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the second paper transport path is provided with gate means for branching the transported paper to the third paper transport path. When the third paper discharge unit is selected and the post-processing of the paper is not selected, the control unit controls the gate unit so that the paper is discharged from the second paper conveyance path to the third paper discharge unit. Features.

According to the above configuration, the second paper transport path is provided with the gate unit that branches the transported paper to the third paper transport path, so that the second discharge unit that communicates with the second paper transport path is provided. When the number of sheets stored in the third paper transport path exceeds the allowable amount, the sheets can be stored in the third discharge unit communicating with the third sheet transport path. As a result, a large amount of paper that is not subjected to post-processing such as staple processing can be conveyed and reliably discharged, so that the convenience of the apparatus can be improved.

According to the eighteenth image forming apparatus of the present invention, in order to solve the above-described problem, when the post-processing of the sheet is set, the sheet is transported to the third sheet discharging unit regardless of the selected sheet discharging unit. It is characterized by:

According to the above configuration, when the post-processing of the sheet is set, the sheet is conveyed to the third sheet discharging section regardless of the selected sheet discharging section, so that the user may erroneously perform an operation other than the third sheet discharging section. Even if the discharge unit is set, the post-processing of the sheet is correctly performed, and the sheet can be discharged to the correct discharge unit.

According to a nineteenth image forming apparatus of the present invention, in order to solve the above-described problem, when the sheet post-processing is set, when the sheet of the type for which post-processing is prohibited is conveyed, the first The paper is discharged using a paper transport path or the second paper transport path.

According to the above configuration, when the post-processing of the sheet is set, when the type of the sheet for which the post-processing is prohibited is conveyed, the first sheet conveying path or the second sheet conveying path is used. By discharging the sheet, even if a user erroneously conveys a sheet for which post-processing is prohibited, the sheet is not subjected to post-processing instead of the third sheet conveying path which is a post-processing conveying path. The sheet is conveyed to the second sheet conveying path where the sheet is conveyed.

Accordingly, a problem caused by the conveyance of the post-processing prohibited sheet to the third sheet conveyance path, which is a post-processing conveyance path, such as a jam or the like, does not occur, and the reliability of the apparatus is improved. Can be.

According to a twentieth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the second paper transport path and the third paper transport path are also used as a drive source for transporting the paper. And

According to the above configuration, since the second paper transport path and the third paper transport path are also used as a drive source for transporting the paper, the number of components constituting the paper transport path in the paper post-processing unit can be reduced. The device can be made compact.

According to a twenty-first image forming apparatus of the present invention, in order to solve the above-mentioned problem, the driving source is a driving roller provided for the second sheet conveying path and the third sheet conveying path for conveying the sheet. It is characterized by consisting of.

According to the above configuration, the drive source is configured by the drive roller for transporting the sheet commonly provided in the second sheet transport path and the third sheet transport path, thereby forming the sheet transport path in the sheet post-processing unit. The number of components to be used and the size of the apparatus can be reduced.

According to a twenty-second image forming apparatus of the present invention, in order to solve the above-described problem, the second paper transport path is disposed above the third paper transport path, and the drive roller is vertically movable. When the paper is transported to the second paper transport path, it moves upward so as to contact the paper transported in the second paper transport path, and when the paper is transported to the third paper transport path, It is characterized in that it moves downward so as to come into contact with the sheet conveyed in the third sheet conveying path.

According to the above configuration, the second paper transport path is disposed above the third paper transport path, the drive roller is provided to be vertically movable, and when the paper is transported to the second paper transport path, When the paper is transported to the third paper transport path, it moves upward to contact the paper transported in the second paper transport path, and moves downward to contact the paper transported in the third paper transport path. By doing so, when the paper is transported through the second paper transport path, the drive roller moves away from the third paper transport path.

Accordingly, when an interrupt request for conveying a sheet that is not subjected to the staple processing is received while the sheet for the staple processing is being conveyed, the staple sheet bundle stacked in the third sheet conveying path includes: Since the drive rollers do not come into contact with each other, misalignment of the sheet bundle such as reverse feeding of the sheet can be eliminated, and the processing can be promptly resumed when the interrupt request is completed.

According to a twenty-third image forming apparatus of the present invention, in order to solve the above-described problem, the driving roller has a conveyance force for conveying a sheet in the second sheet conveyance path for conveying a sheet that is not subjected to post-processing. It is characterized in that the rotation is controlled so as to be stronger than the transport force for transporting the paper in the third paper transport path for transporting the paper to be processed.

According to the above configuration, the drive roller has a conveying force for conveying the sheet in the second sheet conveying path for conveying the sheet not to be post-processed, and the third sheet conveying for conveying the sheet to be post-processed. The sheet conveyed to the third sheet conveyance path is controlled by the rotation control so as to be stronger than the conveyance force for conveying the sheet on the path, so that the sheet bundle already placed on the third sheet conveyance path is It can be transported while abutting smoothly. This makes it possible to prevent the paper or the paper bundle from being damaged or the paper from being damaged when the paper is discharged to the third paper transport path.

According to a twenty-fourth image forming apparatus of the present invention, in order to solve the above-described problem, a document reading unit that reads image information of a document, and an image forming unit that forms an image on a sheet based on image information of the document read by the document reading unit. An image forming unit that forms the image, a first paper discharging unit that is provided below the document reading unit, and that discharges the paper on which the image is formed by the image forming unit, and a first paper discharging unit that transfers the paper from the image forming unit to the first paper discharging unit. A first paper transport path for transporting the paper, a paper post-processing unit for performing post-processing such as stapling on the paper on which the image is formed by the image forming unit, the document reading unit and the first paper discharging unit And is branched into two from the first paper transport path. The second paper discharge unit and the third paper discharge unit formed on the side surface of the apparatus body separately from the first paper discharge unit. A second paper transport path and a third paper transport path for guiding paper are provided. The branching means for branching the paper from the first paper transport path to either the second paper transport path or the third paper transport path can be driven in forward and reverse rotations. The image forming apparatus is characterized in that it is a three-joint roller that selectively conveys the sheet from the image forming section to either the second or third sheet conveying path.

According to the above configuration, the sheet is guided to one of the two nip portions formed by the three connecting rollers. At this time, since the nip that can convey the paper can be switched according to the rotation direction of the central roller, the paper can be reliably sent to the desired paper conveyance path.

According to a twenty-fifth image forming apparatus of the present invention, in order to solve the above-described problem, one of the second paper transport path and the third paper transport path is blocked and the other is blocked depending on the rotation direction of the three connecting rollers. It is characterized in that a transport member for transporting the sheet while being opened is provided.

According to the above configuration, a transport member that transports the paper by opening one of the second paper transport path and the third paper transport path and opening the other according to the rotation direction of the three connecting rollers is provided. This makes it possible to reliably feed the paper to a desired paper transport path.

According to a twenty-sixth image forming apparatus of the present invention, in order to solve the above-mentioned problem, the transport member includes a first gate member having one end connected to a rotation shaft of a central roller of the three connection rollers; The second gate member is connected to the other end of the first gate member and has a substantially central portion formed of a second gate member rotatably supported by a fixed shaft.

According to the above configuration, the transport member is connected to the first gate member, one end of which is connected to the rotation shaft of the center roller of the three connecting rollers, and the other end of the first gate member, Since the substantially central portion is constituted by the second gate member which is rotatably supported by a fixed shaft, when the paper is to be sent to one of the conveying paths, the three connecting rollers want to send the paper. Is rotated in a direction in which a sheet is drawn into a nip portion opposed to a transport path on the side (hereinafter, referred to as a discharge-side transport path).

At this time, the first gate member connected to the central roller is inclined toward the discharge side conveyance path with its rotation. The side of the second gate member that is connected to the first gate member is inclined toward the discharge-side transport path with the movement of the first gate member. Is rotatably supported with respect to the fixed shaft, the end on the side not connected to the first gate member is inclined so as to open the side of the discharge-side transport path.

Therefore, in the transport path switching mechanism using three connecting rollers, the first and second gate members can reliably guide the sheet to the discharge-side transport path. Further, the above configuration is particularly effective when switching the transport path in the horizontal transport path.

駆 動 Further, since the driving force to the gate member is given by the rotating shaft of the three connecting rollers, a driving source for driving the gate member is not required.

他 Besides using the first and second gate members, the following configuration is also possible. That is, in the twenty-seventh image forming apparatus according to the present invention, in order to solve the above-described problem, the transport member includes a first gear formed on a rotation shaft of a center roller of the three connecting rollers; It is characterized by comprising a second gear meshing with the gear, and a paper separation gate provided on the second gear and rotating on the opposite side of the rotation direction of the first gear.

According to a twenty-eighth image forming apparatus of the present invention, in order to solve the above-described problem, the paper path can be dropped by its own weight on the transport path from the three connecting rollers to the paper transport roller provided in the third paper transport path. And the distance between the nip portion of the three connecting rollers and the nip portion of the paper transport roller is set to a paper size that can be post-processed.

According to the above configuration, the conveyance path from the three-connection roller to the paper conveyance roller provided in the third paper conveyance path is formed at an inclination at which the paper can drop by its own weight, and the nip portion of the three-connection roller is formed. The distance between the sheet and the nip portion of the sheet transport roller is set to a sheet size that can be post-processed, so that the sheet of the sheet size that can be post-processed is completely discharged from the nip portion of the three continuous rollers. The leading end is guided by the nip of the paper transport roller. Further, even if the sheet smaller than the sheet size that can be post-processed is completely discharged from the nip portion of the three-connection roller, the leading end thereof is not guided to the nip portion of the paper-conveying roller. To fall.

(4) As a result, only paper of a paper size that can be post-processed is transported to the third paper transport path. In other words, paper smaller than the post-processable paper size (staple-prohibited paper) does not convey on the third paper conveyance path, so that a malfunction such as the occurrence of a jam in the third paper conveyance path due to a malfunction occurs. Can be eliminated.

In addition, whether or not the sheet can be post-processed can be determined only by setting the distance of the transport path, so that it is not necessary to separately provide a paper detection sensor and the like, and the paper transport path can be made simple. .

According to a twenty-ninth image forming apparatus of the present invention, in order to solve the above-mentioned problem, a sheet smaller than a post-processable sheet size is provided between a nip portion of the three connecting rollers and a nip portion of the sheet conveying roller. When the sheet is conveyed, the sheet passes through another nip portion of the three connecting rollers by rotation of a central roller, and is guided to a second sheet conveying path.

According to the above configuration, when a sheet smaller than the post-processable sheet size is conveyed between the nip portion of the three connecting rollers and the nip portion of the sheet conveying roller, the sheet is rotated by the rotation of the central roller. The paper is guided to the second paper transport path through another nip portion of the above-mentioned three connecting rollers, thereby preventing the paper from being jammed between the nip portion of the above three connecting rollers and the nip portion of the paper transport roller. can do.

In order to solve the above-mentioned problems, a thirtieth image forming apparatus according to the present invention includes a document reading unit that reads image information of a document, and an image forming unit that forms an image on a sheet based on the image information of the document read by the document reading unit. An image forming section for forming the image forming section, and a space section serving as a discharge section for discharging a sheet on which an image is formed by the image forming section, wherein the image forming section is disposed below the document reading section. In the image forming apparatus in which is formed, a paper post-processing unit that performs post-processing such as alignment and staple processing of the image-formed paper in a substantially horizontal state is provided between the document reading unit and the space unit, The sheet post-processing unit is provided with a switchback mechanism for conveying the sheet on which an image is formed on one side again to the image forming unit when forming an image on both sides of the sheet.

According to the above configuration, the sheet post-processing unit is provided with the switchback mechanism for transporting the sheet having the image formed on one side to the image forming unit again when forming an image on both sides of the sheet. Thus, the sheet post-processing unit can be used as an intermediate tray for double-sided image formation (hereinafter, referred to as double-sided printing) of a sheet. As a result, the job efficiency of double-sided printing can be improved in a small space and at low cost.

According to a thirty-first aspect of the present invention, in order to solve the above-mentioned problems, the paper post-processing section includes an escape path for conveying a sheet not subjected to post-processing, and a staple tray for conveying a sheet to be post-processed. Is provided on the escape path and the staple tray, a switchback mechanism for inverting the sheet on which an image is formed on one side and transporting the sheet to the image forming unit again so that the image is formed on the side on which the image is not formed. It is characterized by being provided.

According to the above configuration, the switchback in which the sheet on which the image is formed on one side is reversed on the escape path and the staple tray, and is conveyed to the image forming unit again so that the image is formed on the side on which the image is not formed. Since the mechanism is provided, when double-sided printing is performed by interruption while the staple tray is used, a switchback mechanism of an escape path is used. Thus, double-sided printing can be performed without disturbing the stacking property of the sheets on the staple tray.

Further, it is possible to switch back without damaging the paper to be switched back and ensuring the positional accuracy of the paper.

When the staple tray switchback mechanism is used, the staple tray can be used as an intermediate tray, so that a predetermined number of single-sided printing sheets can be stocked. By switching back the single-sided printing paper stocked for a predetermined number of sheets, double-sided printing is completed. Therefore, the efficiency of double-sided printing can be improved.

Specifically, the configuration is as follows. That is, in order to solve the above-mentioned problem, the 32nd image forming apparatus of the present invention employs the above-described escape path switchback mechanism, in which the rear end of the sheet on which one side of the image is formed is inserted into the escape path. The paper feeding roller provided is chucked, and the paper feeding roller is reversely rotated to switch back the sheets one by one.

According to a thirty-third image forming apparatus of the present invention, when the switchback mechanism of the staple tray is used to solve the above-described problem, a predetermined number of sheets of image-formed paper on one side are placed on the staple tray. After the sheets are stored, the sheets are sequentially switched back from the sheet bundle on the staple tray.

According to a thirty-fourth image forming apparatus of the present invention, in order to solve the above-described problem, an alignment member for aligning an end of the staple tray on the opposite side to the post-processing direction is provided in the paper conveyance direction. It is characterized by being provided movably.

According to the configuration described above, the staple tray is provided with an alignment member for aligning the end on the opposite side to the post-processing direction of the paper so as to be movable in the paper conveyance direction. By using the alignment member of (1) as an alignment member when used as an intermediate tray during double-sided printing, the number of members required for the switchback mechanism can be reduced. be able to.

According to a thirty-fifth image forming apparatus of the present invention, in order to solve the above-described problem, a document reading unit that reads image information of a document, and an image forming unit on a sheet based on image information of the document read by the document reading unit. An image forming section for forming the image forming section, and a space section serving as a discharge section for discharging a sheet on which an image is formed by the image forming section, wherein the image forming section is disposed below the document reading section. In the image forming apparatus in which is formed, a paper post-processing unit that performs post-processing such as alignment and staple processing of the image-formed paper in a substantially horizontal state is provided between the document reading unit and the space unit, The paper post-processing section is provided with an escape path for transporting the paper not subjected to post-processing and a staple tray for transporting the paper to be post-processed. The escape path includes a paper transport belt and the paper transport belt. A plurality of paper transport members each comprising a pair of rollers for stretching the paper are provided in parallel in the paper transport direction, and the paper transport members are rotatably provided on the staple tray side around a roller opposite to the paper transport direction as a fulcrum. It is characterized by having.

According to the configuration described above, the paper transporting the escape path can be sent to the staple tray side by rotating the paper transport member that is the transport means of the escape path. Accordingly, it is not necessary to provide a branching unit for branching the paper conveyed from the image forming unit to the escape path or the staple tray near the paper conveyance entrance of the escape path and the staple tray, thereby reducing the number of parts of the apparatus. can do.

According to a thirty-sixth image forming apparatus of the present invention, in order to solve the above-described problems, the paper transport member is located at a home position where the paper transport belt is in a substantially horizontal state when the paper is transported in the escape path. When a staple request is made during image formation, the staple tray is rotated.

According to the above configuration, the paper transport member is located at the home position where the paper transport belt is in a substantially horizontal state when the paper is transported in the escape path, and when a staple request is made during image formation, By rotating to the tray side, the sheet transporting member can be rotated with an arbitrary position on the escape path as a sheet guiding position. Thereby, the paper guide position to the staple tray can be changed according to the paper size, for example.

Specifically, the configuration is as follows. That is, in order to solve the above-described problems, the thirty-seventh image forming apparatus according to the present invention is characterized in that the rotation position of each of the sheet conveying members is switched according to the sheet size.

According to a thirty-eighth image forming apparatus of the present invention, in order to solve the above-mentioned problem, in a state where the paper transport member is rotated to the staple tray side, the paper transport belt is in contact with the staple tray in the paper transport direction. It is characterized in that it rotates.

According to the above configuration, the paper transporting member rotates the paper transport belt in the paper transport direction while abutting on the staple tray in a state of being rotated toward the staple tray, so that the paper fed to the staple tray is rotated. The sheet can be conveyed by a sheet conveying member. This makes it possible to use a common driving unit for conveying the paper between the escape path and the staple tray, thereby reducing the number of parts and reducing the cost of the apparatus.

According to a thirty-ninth image forming apparatus of the present invention, in order to solve the above-described problem, among the paper transport members rotated to the staple tray side, the paper transport member positioned at the most upstream in the paper transport direction is the staple tray. It is characterized in that the angle is set to 90 degrees or less with respect to the sheet mounting surface.

According to the above configuration, among the paper transporting members rotated to the staple tray side, the paper transporting member positioned at the most upstream in the paper transporting direction is at an angle of 90 degrees or less with respect to the paper mounting surface of the staple tray. With the setting, the paper can be smoothly fed into the staple tray.

Specifically, the paper transport belt has the following configuration. That is, in order to solve the above-described problems, a fortieth image forming apparatus according to the present invention is characterized in that the paper transport belt of the paper transport member can rotate forward and backward.

In order to solve the above-described problems, a forty-first image forming apparatus of the present invention includes a document reading unit that reads image information of a document, and an image forming unit that forms an image on a sheet based on the image information of the document read by the document reading unit. An image forming section for forming the image forming section, and a space section serving as a discharge section for discharging a sheet on which an image is formed by the image forming section, wherein the image forming section is disposed below the document reading section. In the image forming apparatus in which is formed, a paper post-processing unit that performs post-processing such as alignment and staple processing of the image-formed paper in a substantially horizontal state is provided between the document reading unit and the space unit, The paper post-processing unit is provided with an escape path for transporting paper not subjected to post-processing and a staple tray for transporting paper to be post-processed, and has an operation surface perpendicular to the paper transport direction and operated by an operator. It is characterized in that the escape path and the staple tray is provided so as to be opened opposite end as a fulcrum.

According to the above configuration, the paper post-processing unit is provided with the escape path for conveying the paper not subjected to post-processing and the staple tray for conveying the paper to be post-processed. The escape path and the staple tray are releasably provided with the end on the side opposite to the operation surface due to the operation surface as a fulcrum, so that if at least one of the escape path and the staple tray is jammed, the operation surface is opened. Therefore, the jam processing can be easily performed.

In addition, if the escape path and the staple tray are opened with a single lever, jamming can be easily performed without removing screws used to open the escape path and the staple tray from the apparatus. And the like can be resolved.

According to a forty-second image forming apparatus of the present invention, in order to solve the above-mentioned problem, the escape path and the staple tray are simultaneously opened in a space formed below the document reading unit. I have.

According to the above configuration, the escape path and the staple tray are simultaneously opened in the space formed below the document reading unit, thereby opening the space for opening the escape path and the staple tray. There is no need to provide a separate device, and the installation space of the device can be effectively used.

According to a forty-third image forming apparatus of the present invention, in order to solve the above problem, the escape path is disposed on an upper surface side of the staple tray, and a lower surface member of the escape path, and an upper surface member of the staple tray. Is constituted by a common member, wherein the common member is rotatably provided on the escape path side so as to open only the staple tray when the escape path and the staple tray are in an open state. I have.

According to the above configuration, when the escape path and the staple tray are opened, the lower surface member of the escape path and the common member forming the upper surface member of the staple tray are pushed down, so that the escape path and the staple tray can be moved in one action. The staple tray can be opened at the same time. Moreover, only the staple tray can be opened only by lifting the common member.

According to a forty-sixth image forming apparatus of the present invention, in order to solve the above-described problems, the escape path is disposed on an upper surface side of the staple tray, and a lower surface member of the escape path, and an upper surface member of the staple tray. Are formed of a common member, and the common member is formed with a jam detection mechanism for detecting a jam in the staple tray and the escape tray with one sensor.

According to the above configuration, since the jam detection mechanism in both transport paths (escape path and staple tray) is performed by one sensor, wiring and the like in the jam detection mechanism can be simplified. As a result, the size of the device can be reduced, and the cost for manufacturing the device can be reduced.

構成 Specifically, the configuration of the above sensor is as follows. That is, in order to solve the above problem, in the forty-fifth image forming apparatus of the present invention, the sensor includes: an optical light emitting unit; a light receiving unit for receiving irradiation light from the light emitting unit; It may be constituted by an arm member that blocks the light receiving unit by being transported and abutting.

Furthermore, the arm member is specifically as follows. That is, in the forty-sixth image forming apparatus of the present invention, in order to solve the above-described problem, the arm member has one end abutting on a sheet to be conveyed and the other end having the fulcrum through the fulcrum. The light receiving unit may be rotatably provided around a fulcrum provided on the common member so as to block the light receiving unit.

The present invention can be applied not only to a single-function image forming apparatus such as a copying machine, a facsimile apparatus, and a printer, but also to a multifunction apparatus having a copying function, a facsimile function, and a printing function. It can be suitably used for an image forming apparatus.

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic explanatory view illustrating a main part of a sheet conveyance system in the image forming apparatus main body of the image forming apparatus illustrated in FIG. 1. FIG. 2 is a schematic explanatory diagram illustrating a main part of a sheet conveyance system in the post-processing device of the image forming apparatus illustrated in FIG. 1. FIG. 2 is a schematic explanatory diagram illustrating a main part of a sheet transport system in a sheet stack unit of the image forming apparatus illustrated in FIG. 1. FIG. 5 is an explanatory diagram illustrating the vicinity of a staple unit in a sheet stack unit illustrated in FIG. 4. FIG. 6 is a schematic perspective view near the staple unit shown in FIG. 5. FIG. 2 is a schematic plan view schematically illustrating an alignment member in a staple tray in the post-processing apparatus of the image forming apparatus illustrated in FIG. 1. FIG. 8 is a schematic sectional view of the staple tray shown in FIG. 7. FIG. 9 is an explanatory diagram illustrating an operation of a feeding member of the staple tray illustrated in FIG. 8. FIG. 9 is an explanatory diagram illustrating an operation of a feeding member of the staple tray illustrated in FIG. 8. 3 is a flowchart illustrating a flow of a sheet conveying operation when an offset function is selected in the image forming apparatus illustrated in FIG. 1. 3 is a flowchart illustrating a flow of a sheet conveying operation when a staple function is selected in the image forming apparatus illustrated in FIG. 1. FIG. 2 is a schematic configuration diagram of the image forming apparatus in a state where a post-processing device is removed from the image forming apparatus illustrated in FIG. 1. FIG. 9 is a schematic configuration diagram of an image forming apparatus according to another embodiment of the present invention. FIG. 4 is an explanatory diagram showing an example in which a drive roller for carrying a sheet between an escape path and a staple tray is also used in the image forming apparatus of the present invention. FIG. 4 is an explanatory diagram showing an example in which a drive roller for carrying a sheet between an escape path and a staple tray is also used in the image forming apparatus of the present invention. It is explanatory drawing which shows an example of the transmission means of the driving force from the said drive roller to a double use roller. It is explanatory drawing which shows the other example of the transmission means of the driving force from the said drive roller to a double use roller. FIG. 5 is an explanatory diagram illustrating a case where a triple connecting roller is used as a sheet branching unit in a sheet conveyance path in the image forming apparatus of the present invention. (A) is a plan view of the three-joint roller shown in FIG. 19, and (b) is a side view of the three-joint roller shown in FIG. 19. FIG. 9 is an explanatory diagram illustrating another example in which a three-joint roller is used as a sheet branching unit in a sheet conveyance path in the image forming apparatus of the present invention. FIGS. 7A and 7B are explanatory views showing still another example of a case where a three-joint roller is used as a sheet branching unit in a sheet conveying path in the image forming apparatus of the present invention. FIG. 2 is an explanatory diagram illustrating an example of a sheet conveyance system in the image forming apparatus of the present invention. FIG. 3 is an explanatory diagram illustrating an example of a case where a post-processing device in the image forming apparatus of the present invention is used as an intermediate tray in double-sided printing. FIG. 25 is a schematic perspective view of the vicinity of a staple tray in the post-processing apparatus shown in FIG. 24. FIG. 9 is an explanatory diagram illustrating a modified example of the escape path in the post-processing device in the image forming apparatus of the present invention. FIG. 27 is an explanatory diagram showing the operation of the escape path shown in FIG. 26. FIG. 27 is an explanatory diagram showing the operation of the escape path shown in FIG. 26. FIG. 27 is an explanatory diagram showing the operation of the escape path shown in FIG. 26. FIG. 27 is an explanatory diagram showing an operation of a sheet conveying member constituting the escape path shown in FIG. 26. FIG. 27 is an explanatory diagram showing an operation of a sheet conveying member constituting the escape path shown in FIG. 26. FIG. 27 is an explanatory diagram showing an operation of a sheet conveying member constituting the escape path shown in FIG. 26. FIG. 2 is a schematic perspective view of a post-processing device of the image forming apparatus of the present invention. 34 is a cross-sectional view of the post-processing device shown in FIG. FIGS. 34A to 34C are explanatory diagrams showing a jam clearing operation in the post-processing apparatus shown in FIG. FIG. 3 is a schematic configuration diagram illustrating a jam detection mechanism that detects a sheet in the post-processing device of the image forming apparatus of the present invention. (A), (b) is a schematic block diagram of the paper detection sensor provided in the jam detection mechanism. FIG. 37 is an explanatory diagram illustrating an operation of detecting a transfer sheet of an escape path in the jam detection mechanism illustrated in FIG. 36. FIG. 37 is an explanatory diagram illustrating an operation of detecting a transfer sheet of an escape path in the jam detection mechanism illustrated in FIG. 36. FIG. 37 is an explanatory diagram illustrating an operation of detecting a transfer sheet on a staple tray in the jam detection mechanism illustrated in FIG. 36. FIG. 37 is an explanatory diagram illustrating an operation of detecting a transfer sheet on a staple tray in the jam detection mechanism illustrated in FIG. 36. FIG. 10 is a schematic configuration diagram of a conventional image forming apparatus. FIG. 4 is an explanatory diagram illustrating an example of a state in which a post-processing device is provided in the image forming apparatus. FIG. 9 is an explanatory diagram illustrating another example of a state in which a post-processing device is provided in the image forming apparatus. FIG. 10 is a schematic configuration diagram of a conventional image forming apparatus. FIG. 10 is a schematic configuration diagram of a conventional image forming apparatus.

Explanation of reference numerals

100 Document reading unit 200 Image forming apparatus main body 210 Image forming unit 220 Paper feeding / conveying unit 221 Paper cassette 222 Manual feed tray 223 Call-in roller 224 Pick-up roller 225 First paper feed path 226 Call-in roller 227 Pick-up roller 228 Second paper feed path 229 Registration Roller 230 Fixing roller 231 Paper transport path 232 Discharge roller 233 First paper transport path 234 First paper discharge section 235 First switching gate 236 Paper transport path 237 Reverse transport path 238 Switching gate 300 Post-processing device (paper post-processing section)
301 Paper transport path 302 Escape path (second paper transport path)
302a Central paper guide (upper surface member, lower surface member, common member)
302c Upper paper guide 303 Staple tray (third paper transport path)
303b Transport guide 304 Second switching gate 305 First paper discharge path 306 Second paper discharge path 307 Third switching gate 308 Staple unit 309 Paper discharge roller 310 Transport roller 311 First alignment unit (recess)
312 Second matching part (recess)
313 Feeding member 314 Holding lever 316 Feeding roller 318 Discharge roller 319 Roller arm 320 Support shaft 331 Pressure roller 332 Drive source 333 Drive transmission unit 334 Drive transmission unit 350 Switching means (three continuous rollers)
351 First roller 352 Second roller 353 Third roller 354 First gate member 356 Second gate member 357 Fixed shaft 360 Switching means 361 First gate member 362 Second gate member 370 Switching means 371 First gate member 372 Second gate Member 381 First transport path 382 Second transport path 383 Third transport path 384 Fourth transport path 391 First discharge transport path 392 Second discharge transport path 400 Paper stack unit 401 First paper stack tray (second paper discharge unit)
402 Second paper stack tray (third paper discharge unit)
Reference numeral 501 Stopper 502 Paper leading end pressing lever 503 Stapler 504 Feeding roller 505 Alignment member 509 Fixed wall 600 Reverse conveying means 601 Re-feeding belt 602 Conveying plate 603 Paper pressing lever 604 Separating member 651 Back frame member 652 Front frame member 653 Top plate 658 Lever 700 Escape path (second paper transport path)
701 Paper transport member 702 Paper transport belt 703 Roller 704 Driving roller 705 Driven roller 706 Stopper 800 Paper detection sensor (jam detection means, jam detection mechanism)
801 Optical sensor 801a Light emitting unit 801b Light receiving unit 802 Arm (arm member)
802a End 802b End 803 Arm (arm member)
803a End 803b End 804 Support shaft (fulcrum)

Claims (19)

A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
A sheet post-processing unit attached to the apparatus main body including the image forming unit and performing post-processing of the sheet on which the image is formed;
In the image forming apparatus, a space is formed below the document reading unit as a discharge unit for discharging the sheet on which the image is formed by the image forming unit.
An upper discharge port and a lower discharge port for discharging the sheet are disposed in the space, and connected to the upper discharge port to relay the sheet from the image forming section to the sheet post-processing section. An image forming apparatus, wherein a transport path is formed. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus comprising: a sheet post-processing unit that performs post-processing of a sheet on which an image is formed by the image forming unit;
Below the document reading unit, a space is formed in which a discharge port for discharging a sheet on which an image has been formed by the image forming unit is formed, and the space is connected to the discharge port. A relay conveyance path for conveying from the forming unit to the paper post-processing unit is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus comprising: a sheet post-processing unit that performs post-processing of a sheet on which an image is formed by the image forming unit;
A space in which a discharge port for discharging a sheet on which an image is formed by the image forming unit is formed below the document reading unit,
The paper post-processing unit is attached to the space,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
A sheet stack unit attached to the apparatus main body including the image forming unit and discharging an image-formed sheet;
An image forming apparatus, wherein a space as a discharge unit for discharging a sheet on which an image is formed by the image forming unit is formed below the document reading unit.
An upper discharge port and a lower discharge port for discharging the paper are disposed in the space, and connected to the upper discharge port to relay the paper from the image forming unit to the paper stack unit. An image forming apparatus, wherein a path is formed. A document reading unit for reading image information of the document,
An image forming unit that forms an image on paper based on image information of the document read by the document reading unit;
An image forming apparatus comprising: a sheet stack unit configured to discharge a sheet on which an image is formed by the image forming unit;
Below the document reading unit, a space is formed in which a discharge port for discharging a sheet on which an image has been formed by the image forming unit is formed, and the space is connected to the discharge port. A relay conveyance path for conveying from the forming unit to the paper stack unit is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. 6. The image forming apparatus according to claim 1, wherein the relay conveyance path is provided on a back surface of the document reading unit. 7. 6. The image forming apparatus according to claim 1, wherein the relay conveyance path is provided between the document reading unit and the space. 6. The image forming apparatus according to claim 1, wherein the relay conveyance path is provided with a jam detection unit that detects that a sheet is jammed in the relay conveyance path. 7. apparatus. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of a sheet on which an image is formed;
A space surrounded by an outer peripheral wall of the apparatus main body is formed below the document reading unit, and a sheet is processed between the image forming unit and the sheet post-processing between the document reading unit and the space. A relay conveyance path for conveying to the section is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of a sheet on which an image is formed;
A discharge unit for discharging the sheet on which the image is formed by the image forming unit is formed below the document reading unit, and the sheet is formed between the document reading unit and the discharge unit. A relay transport path for transporting the sheet from the unit to the paper post-processing unit is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of a sheet on which an image is formed;
A discharge unit for discharging the sheet on which the image is formed by the image forming unit is formed below the document reading unit, and a sheet is placed on the back of the document reading unit from the image forming unit after the sheet. A relay transport path for transporting to the processing unit is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of a sheet on which an image is formed;
A discharge unit for discharging the sheet on which the image is formed by the image forming unit is formed below the document reading unit, and a sheet is placed on the ceiling surface of the discharge unit after the sheet from the image forming unit. A relay transport path for transporting to the processing unit is formed,
The image is characterized in that at least a part of the relay conveyance path is provided in a direction perpendicular to the sheet conveyance direction and is openable downward with a fulcrum at an end opposite to a surface operated by an operator of the apparatus. Forming equipment. The image forming apparatus according to any one of claims 9 to 12, wherein the relay conveyance path includes a jam detection unit that detects that a sheet is jammed in the relay conveyance path. apparatus. A document reading unit for reading image information of the document,
An image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit;
An image forming apparatus provided with a sheet post-processing unit attached to an apparatus main body including the image forming unit and performing post-processing of a sheet on which an image is formed;
A space is formed below the document reading unit as a discharge unit which is surrounded by the outer peripheral wall of the apparatus main body and discharges a sheet on which an image is formed by the image forming unit, and is formed above the discharge unit. An image forming apparatus, wherein a relay conveyance path for conveying a sheet from the image forming unit to the sheet post-processing unit is formed on a back surface of the document reading unit. A document reading unit for reading image information of the document,
An image forming apparatus comprising: an image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit.
Below the document reading unit, a space is formed, which is surrounded by the outer peripheral wall of the apparatus main body including the image forming unit and serves as a discharge unit for discharging a sheet on which an image is formed by the image forming unit,
Above the discharge unit, and on the back of the document reading unit, a relay conveyance path for conveying a sheet from the image forming unit to a discharge unit different from the space unit is formed,
An image forming apparatus, wherein the relay conveyance path is provided with a switchback mechanism for conveying a sheet having an image formed on one side to an image forming unit again when images are formed on both sides of the sheet. . A document reading unit for reading image information of the document,
An image forming apparatus comprising: an image forming unit that forms an image on a sheet based on image information of a document read by the document reading unit.
Below the document reading unit, a space is formed, which is surrounded by the outer peripheral wall of the apparatus main body including the image forming unit and serves as a discharge unit for discharging a sheet on which an image is formed by the image forming unit,
Above the discharge unit, and on the back of the document reading unit, a relay conveyance path that conveys paper from the image forming unit to a discharge unit different from the space unit is formed,
The image forming apparatus, wherein the relay conveyance path is provided to be openable in the space. 17. The image forming apparatus according to claim 14, wherein the relay conveyance path is provided with a jam detection unit for detecting that a sheet is jammed in the relay conveyance path. apparatus. The jam detecting means includes an optical light emitting unit, a light receiving unit for receiving irradiation light from the light emitting unit, and an arm member for interrupting the light receiving unit by conveying and abutting a sheet. 18. The image forming apparatus according to claim 17, comprising a sensor. 19. The image forming apparatus according to claim 1, wherein the relay conveyance path is unitized so as to be detachable from the apparatus main body.

Images