JPH03243393A - Paper transport mechanism of image forming apparatus - Google Patents

Abstract

PURPOSE:To miniaturize an apparatus itself and to efficiently feed paper at high speed by providing a common change-over mechanism alternatively switching over from the operation to stop of feed motion to the paper feed means in a forward direction feed path and the paper feed means in an orthogonal direction feed path. CONSTITUTION:The operation and stop of the feed motions in forward direction feed rollers 923-925 and an orthogonal direction feed roller 926 are alternatively changed over from one to another by a common change-over mechanism. Pinch rollers 923a-925a are brought into contact with the forward direction feed rollers 923-925 under pressure to feed recording paper from a forward direction feed path to an orthogonal direction feed path. When the recording paper reaches a predetermined position, the rollers 923a-925a are separated and the application of forward direction feed force is stopped. At the same time, a pinch roller 926a is brought into contact with the orthogonal direction feed roller 926 under pressure and the feed force in the orthogonal direction is applied to the recording paper and the recording paper is always rapidly converted in its direction at a definite position to be sent out to a sorter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus in which a finisher for post-processing recording paper in a sorter is attached to an image forming main body. relates to a conveyance mechanism for recording paper supplied to this apparatus.

[Prior Art] As is well known, in various image forming apparatuses such as copying machines, printers, and facsimile machines, a finisher consisting of a sorter or the like for sorting recording paper is sometimes attached to the image forming main body. .

A general image forming main body is often of a side-operated type in which handling such as ejection and sorting of recording sheets is performed from a side area of the main body.

For this reason, the image forming main body is provided with an image forming conveyance path for conveying the recording paper from one side toward the other side, and the finisher is provided in the image forming main body. They are arranged in parallel and connected to the exit portion of the image forming conveyance path, that is, to the side of the image forming main body.

[Problems to be Solved by the Invention] However, in such an image forming apparatus, as described above, since the image forming main body is configured as a side-operated type, the entire apparatus becomes long in the left and right direction. In addition, various operations such as removing recorded recording paper on which image formation has been performed from the tray, or loading a paper cassette containing unrecorded paper into the image forming main unit are performed by the image forming device. This will be done on both sides. Therefore, space for the above-mentioned operations is required on both sides of the image forming apparatus.

Moreover, in this space, there must be enough room to prevent pedestrians from colliding with trays, etc.
In view of these circumstances, when installing an image forming apparatus, a space larger than that required for actual operation is required. Therefore,
When such an image forming apparatus is installed in a relatively narrow space, the various operations described above may be hindered.

Therefore, in order to solve this problem, the above-mentioned conveyance path of the recording paper is changed from the inside of the image forming main body to a right angle direction, and is set to face the front side and the back side of the image forming main body by ``f''. It is also possible to do so (for example, Japanese Patent Application No. 150842/1999 filed by the present applicant).

However, in an image forming apparatus configured with the above-mentioned transport path, for example, when continuous paper feeding is performed, it is necessary to prevent the following recording paper from interfering with the preceding recording paper at the time when the feeding direction is switched. It is necessary. For this reason, efforts have been made to suppress the decrease in speed during continuous paper feeding by increasing the conveyance interval of the recording paper or by increasing the speed during perpendicular conveyance. However, in this method, since the conveyance interval is not constant depending on the type of recording paper being conveyed, it is difficult to control the conveyance speed according to the type of recording paper being conveyed. It becomes a hassle.

Furthermore, in the conventional image forming apparatus, the length of the recording paper that can be transported is set to be the maximum length, which causes the following problem.

That is, the copy modes in the above-mentioned image forming apparatus include single-sided copying, double-sided copying, and single-sided composite copying, and the image forming apparatus must be set to have a length sufficient to convey recording paper compatible with each of these modes. - The paper size used in the shell is B4, A4, B5.
Among these, the paper sizes commonly used for double-sided copying are A4 and B5.

Therefore, when transporting recording paper of the above-mentioned sizes that are frequently copied, if the transport path set for transporting recording paper of a size larger than these sizes is used for transporting each of these recording papers, especially. During double-sided copying, it takes a long time to proceed to the next image formation, and the copying process itself takes a long time, resulting in poor copying efficiency.

In addition, if the recording paper is ejected onto the top surface of the image forming apparatus, there is a risk that the document placement table will overlap with the document setting position because it is located on the top surface, so coexistence will be realized by distinguishing each process of the two. It is impossible to do so.

Furthermore, it is difficult due to the location to connect a sorter, stapler, or other peripheral device for sorting the recording paper used to process the recording paper after it has been discharged to the recording paper discharge section described above.

Furthermore, the above-mentioned recording paper is often ejected with the image side facing upward, and the ejected recording paper is loaded in the reverse order of the page order on the original side. will be placed. Therefore, in order to organize the recording sheets after copying, it is necessary to copy from the rear of the original in page order, which is a hassle. However, when copying using this procedure, if you make double-sided copies from an odd number of single-sided originals, the first page of the finished copies will not be the cover, but will be blank, and the second and subsequent pages will be blank. 1st
A problem with non-page order processing occurs in that images from pages are copied.

Therefore, the present invention can reduce the size of the device itself, eliminate the need to provide a large operating space around it, can be installed in a space-saving manner, and can convey paper efficiently at high speed. A further object of the present invention is to provide an image forming apparatus that can eject recording sheets in the order of pages of a document.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a forward transport path for transporting the recording paper on which an image is formed and is ejected toward the front side and the back side. A front-operated image forming main body section, a finisher for recording paper post-processing arranged in parallel on the side of the image forming main body section, and a finisher arranged at a substantially right angle to receive the recording paper discharged from the forward conveyance path. In the paper conveyance mechanism of an image forming apparatus, the paper conveyance mechanism of an image forming apparatus is provided with a perpendicular conveyance path connected to the forward conveyance path so as to convey the recording paper in the forward direction and feed the recording paper to the finisher; The paper feeding means and the paper feeding means in the orthogonal direction conveyance path are characterized in that a common switching mechanism is attached to selectively switch between activation and stop of the conveyance operation.

Further, the present invention includes a forward conveyance path for conveying the recording paper, which is ejected after image formation is performed at a predetermined image forming process speed, toward the front side and the back side at a predetermined paper feeding speed. A front-operated image forming main body section, a finisher for recording paper post-processing arranged in parallel on the side of the image forming main body section, and a finisher arranged at a substantially right angle to receive the recording paper discharged from the forward conveyance path. In the paper transport mechanism of an image forming apparatus, the paper transport mechanism includes a perpendicular transport path that is connected to the forward transport path so as to transport the recording paper in the forward direction and feed the recording paper to the finisher. is configured such that it is possible to select either a paper conveyance speed V□, which is the same as the image forming process speed, or a paper conveyance speed ■2, which is increased in a fixed relationship with respect to the image forming process speed. In addition, the paper feeding means in the forward direction conveyance path transports the paper with reference to the recording sheet for which the difference (hi) between the paper width dimension in the conveying direction of the recording sheet and the interval dimension i between each recording sheet is the largest. It is characterized by being configured so that the speed can be set.

Further, in the present invention, the paper feeding means in the forward direction conveyance path is configured such that the paper conveyance speed is set by a signal that detects the trailing edge of the recording sheet immediately after exiting the fixing device. It is characterized by the presence of

Further, in the present invention, the paper feeding means in the forward direction conveying path is configured to have the same paper conveying speed V1 as the image forming process speed, and the paper feeding means in the orthogonal direction conveying path is configured to have the same paper conveying speed V1 as the image forming process speed. It is characterized in that it is configured to have a paper transport speed V2 that is increased in a constant relationship with respect to the process speed.

Furthermore, in the present invention, the paper feeding means in the forward direction conveying path sets a paper conveying speed for each size of recording paper based on the paper width dimension of the recording paper and the interval dimension i between each recording paper. It is characterized by being configured as follows.

Furthermore, the present invention is provided with a conveyance path in which the conveyance direction of the recording paper is set from the front side to the back side with respect to the operation surface of the copying machine, and the recording paper is conveyed and circulated in this conveyance direction. In the image forming apparatus, the recording paper ejection port is provided on the top surface of the copying machine and on one side of the copying machine in a direction perpendicular to the transport direction, respectively, in the transport direction in the transport path. A small size switchback conveyance path is located immediately downstream of the fixing device, and is provided separately from the above-mentioned top side discharge port to set the conveyance path to the paper refeeding device for double-sided copying. a large size switchback conveyance path located downstream of the size switchback conveyance path, which branches from the discharge path toward the discharge port on the top surface of the copying machine and sets a conveyance path toward the refeeding device for double-sided copying; a composite copying conveyance path that branches from a discharge path toward the discharge port on the top surface of the copying machine and sets a conveyance path toward the double-sided copying refeeding device;
A right angle that branches from the transport path set for double-sided copying and composite copying of the large-sized recording paper and converts the transport direction of the recording paper to a right-angled direction at a position different from the refeeding device for double-sided copying. It is characterized by having a conveyance path.

The present invention also provides a method for conveying the recording paper when the recording paper is performing an image transfer process between it and the image forming photoreceptor during the conveyance path from the front side to the back side with respect to the operation surface. The present invention is characterized by setting the relationship Vl<V2, where vl is the speed and vl is the conveyance speed of the recording paper during execution of other copying processes.

Furthermore, the present invention branches from a transport path set for double-sided copying and composite copying of large-sized recording paper, and at a position different from the refeeding device for double-sided copying, the transport direction of the recording paper is directed perpendicularly. Located on the extension of the right-angled conveyor path, which converts into
The present invention is characterized in that it includes a paper reversal storage section that stores the recording paper transported from the perpendicular transport path in a state in which the image surface direction of the stored recording paper is switched in the transport direction.

[Function] In the means according to the present invention, first, since the image forming main body is configured to be operated from the front, it is possible to take out recorded paper on which an image has been formed from the tray or unrecorded paper. All operations, such as attaching the stored paper feed force cellar 1 to the image forming main body, are performed from the front side of the image forming apparatus, so there is space for operation and space on both sides of the apparatus. No extra space is required, and three sides of the device except the lower front side can be placed close to the wall.

In addition, for the finishers arranged in parallel on the side of the image forming main body, from the conveyance path in the right angle direction of the image forming main body,
The recorded paper is fed out with its direction changed in a direction perpendicular to the feeding direction of the forward conveyance path.

As a result, post-processing operations such as sorting of recording sheets are performed. The recording paper after post-processing is also taken out from the front side. Therefore, in the finisher as well, there is no need for a space for operation and a space for clearance on both sides of the device, and three sides of the device except the front side can be brought close to the wall surface.

In such a perpendicular discharge operation for the finisher, the recording paper transport direction switching operation from the forward transport path to the perpendicular transport path is performed by a single switching mechanism with a simple configuration. The reliability and high speed of the recording paper conveyance direction switching operation are improved.

In addition, in the perpendicular discharge operation to the finisher described above, the paper feed speed in the forward direction conveyance path is determined so that the distance between the preceding recording paper and the following recording sheet in the forward direction conveyance path is greater than a certain value. As a result, after the preceding transfer paper is received at the entrance of the right-angled conveyance path and sent out from there, the trailing transfer paper enters the entrance of the right-angled conveyance path. Interference due to overlap between the preceding recording paper and the following recording paper is reliably prevented at the inlet portion of the paper, and a good ejection operation is performed.

Furthermore, according to the present invention, when double-sided copying is performed on small-sized recording paper, the recording paper is printed after the image is fixed.

The sheet is immediately introduced into the small size switchback conveyance path in the conveyance path and brought to the refeeding device for double-sided copying.

Further, according to the present invention, the time required to convey the recording paper at times other than during transfer is shortened.

Further, according to the present invention, the image side of the recording paper to be discharged can be switched to either the front or the back side, and the recording paper can be discharged.
You can set the page order to your desired order.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

First, the structure of the image forming body in the image forming apparatus according to the embodiment of the present invention will be explained together with its functions in the copying machine shown in FIG.

That is, the image forming main body section is the copying machine main body C.

It is comprised of a multi-stage paper feeder (PB) 400 installed at the bottom of the copying machine main body C, and an automatic reversing original document device (ARDF) 100 installed at the top of the copying machine main body C.

In the copying machine main body C, an original to be copied is inserted from the position shown by arrow A and stopped at a predetermined position on the contact glass 203. The operation of setting the original will be described in detail in the section on the automatic reversing original document feeder (ARDF) described later.

Next, an exposure process is performed by the optical system 200. The optical system 200 is arranged under a contact glass 203 so that the original image can be scanned, and includes a JM manuscript illumination light source 201, a movable mirror 204°205, 206, a zoom lens 207, and fixed mirrors 208, 209. , 210.

The document illumination light source 201, the reflector 202, and the movable mirror 204 constitute a first scanner 220, and the first scanner 220 ;m is the copying magnification), and at the same time the movable mirror 205,
206, the second scanner 230 consists of (V/2
It is rotated and opened by a drive motor (not shown) so that it can be moved rightward in the figure at a speed of m).

Note that the circumferential speed of the photoreceptor drum 601 is constant regardless of whether the magnification is equal to the magnification or variable magnification.

The copy magnification is changed by changing the position of the zoom lens 207 on the optical path by driving a lens drive motor (not shown). In the figure, a zoom lens 207
When the position of is at I, m=0.5 (50% reduction),
m = 1.0 (same size) when in H, m when in G
=2.0 (200% enlargement).

A photosensitive drum 60 is located slightly to the right of the center of the copying machine body C.
An image forming system 600 is arranged around ↓. Specifically, around the photoreceptor drum 601 are a charger 602 that uniformly charges the photoreceptor drum 601, an eraser 603 that erases unnecessary charges, and a first developer that visualizes toner powder on the electrostatic latent image using a magnetic brush. A device 502, a second developing device 501, a belt transfer device 630 that transfers the toner image on the photoreceptor drum 601 onto recording paper, and a belt transfer device 630 that cleans the toner image remaining on the photoreceptor drum 601 without being transferred to the recording paper. Cleaning gear! 608 etc. are arranged.

The belt transfer device 630 is constructed by lightly pressing an endless belt 6↓3 stretched by a plurality of rollers 614 or the like against a photosensitive drum 601, and a charger 609 performs corona discharge for transfer from the back side of the belt. . The charger 612 charges the endless belt 613 and electrostatically attracts the recording paper. charger 6
Reference numeral 10 denotes a charger for eliminating static electricity from the endless belt 613. The rubber blade 615 is for cleaning the residue on the endless belt 613 after conveying the paper.

On the other hand, there are two main paper feeding units for recording paper: one is the multi-manual paper feeding device 300 attached to the main body, and the other is located below the bottom of the copier. This is a multistage paper feeder (PB) 400 that includes a plurality of paper feed trays. Paper guide 301 of multi manual paper feeder 300
is normally closed, and when used, it is opened as shown in the figure and recording paper is set.

Also, the set recording paper is transferred to the calling roller 30.
2, and only one sheet is fed by the paper feed roller 303 and separation roller 304. After being temporarily stopped by a pair of registration rollers 305, the photosensitive drum 60
While being synchronized with the leading edge of the image above, the paper is fed along the conveyance direction set from the front side of the operation section on the right side in the figure to the back side of the operation section on the left side in the figure. Ru. In this case, as for the conveyance speed, if the speed when executing the transfer process is Vl, and the speed when executing processes other than this process is V2, the relationship is Vl<V2, and the conveyance time is shortened. .

On the other hand, in the paper feeding operation by the multi-stage paper feeding device 400, the paper feeding device 41 first moves toward the paper tray of the selected paper feeding stage.
0 is raised and lowered. When the selected paper reaches the tray, the vertical movement of the paper feeder 410 is stopped in response to a signal from a sensor (not shown), and then the paper tray is moved toward the paper feeder. The paper feeding method is basically the same as that of a multi-manual paper feeding device.

That is, the paper is sent to the paper feed roller 412 by the pick-up roller 411, and then separated into one sheet by the paper feed roller 412 and separation roller 413 and fed out.From the feeding position, for example, a conveyor belt equipped with a suction mechanism 419 and is fed toward the conveyance roller 306.

Then, the fed paper passes through a conveyance roller 306, reaches a pair of registration rollers 305, and is stopped. The paper, which has passed through a pair of registration rollers 305 and is held by an endless belt 613 and has a toner image transferred thereto, has the toner image fused by a pair of heat rollers (fixing roller 701 and pressure roller 702).

The recorded paper after fixing, so-called recording paper (hereinafter referred to as transfer paper), passes through a pair of fixing paper ejection rollers 701 and 702 in the transport path along the above-mentioned transport direction, and then reaches the ejector located on the top surface of the copying machine main body. The paper passes through a conveyance path 822 set to face the paper tray 809 to the main body discharge tray 809 , paper refeeding device 900 , or sorter conveyance section 950 .

A sensor 801 for detecting the trailing edge of the transfer paper is arranged immediately after passing the pair of fixing and discharging rollers described above, and a guide game 1-8 is located downstream of this sensor 801.
03, a conveyance path 821 is provided which branches from the conveyance path formed by the roller pair 802 and 804 and constitutes a small-size switchback conveyance path for conveying the transfer paper toward a refeeding device 900 for double-sided copying, which will be described later. It is. This small size switchback conveyance path 821 is, as will be described later,
This is a conveyance path used when performing double-sided copying of transfer paper smaller than this size.

In addition, the above-mentioned small size switchback conveyance path 821
Behind the so-called downstream side of the switchback conveyance path 821 in the conveyance direction of the recording paper, there is a mechanism for detecting the trailing edge of the transfer paper in the middle of the conveyance path toward the paper discharge tray 809 located on the top surface of the copying machine. A sensor 810 is arranged, and a pair of rollers 806 that can rotate in forward and reverse directions is located downstream of this sensor 810. This pair of rollers 806 and a guide gate 811 move the conveyance formed by the pair of rollers 802 and 804. A conveyance path 824 is provided that branches from the path and constitutes a large-size switchback conveyance path for conveying the transfer paper toward a double-sided copy refeeding device 900 to be described later.

In other words, when performing single-sided copying, there are two types: A4 (or L T ) size or smaller and other sizes.
Two different transport paths are used.

First, if the paper is A4 (or LT) size or smaller, when the trailing edge of the transfer paper passes through the fixing device 700, the sensor 801
Immediately after the transfer paper passes through the gate 803 in response to a signal from
Head to 1. After passing through the pair of rollers 901, the calling roller 908 is lowered and rotated, and the transfer paper is conveyed to just below the paper feed roller 909. Pressure plate 9 except when feeding paper
Reference numeral 11 is located below and is raised during paper feeding to apply paper feeding pressure to the paper feeding roller 909 . The separation roller 910 is
When the torque is below a certain level, counterclockwise rotation is applied, but when more torque is applied, the transfer paper is rotated along with the paper feed roller 909, thereby feeding the transfer paper one sheet at a time. be done. The re-fed transfer paper is
After being conveyed until a predetermined slack is given by a pair of registration rollers 305, it is stopped and restarted in synchronization with the leading edge of the image on the photoreceptor. The subsequent steps are the same as for single-sided copying.

Therefore, by introducing small-sized recording paper of A4 size or smaller into the small-size switchback conveyance path 821, the paper refeeding device 900 for double-sided copying can avoid passing through the conveyance path of recording sheets of this size or larger. Since the sheet is fed at the same time, the conveyance speed other than the transfer process is fast, and the time required for single-sided copying until the paper feed start time is shortened.

On the other hand, in the case of paper larger than A4 (or LT), the transfer paper passes through a fixing device and a guide gate 803 for introduction into the small size switchback conveyance path, and then passes through a pair of rollers 802 and 804. Pass through gate 8↓1
When the trailing edge is detected by the sensor 810, the pair of rollers 806 is reversed, and the transfer paper is conveyed toward the above-mentioned refeeding device 900 for double-sided copying and toward the right-angled conveyance path described later. It is sent to a conveyance path 824 that constitutes a switchback conveyance path for large sizes. At this time, the gate 814 is displaced to the position indicated by the broken line, and the transfer paper is sent to the pair of rollers 902.

When the size of the transfer paper is A3 (or 17'), the gate 905 takes the position shown by the broken line, and immediately after passing the pair of rollers 902, it is ejected onto the paper refeeding device. Transfer paper size is B4
(or 14'), the gate 9.5 takes the position shown by the solid line, and the gate 906 takes the position shown by the broken line, so that the transfer paper that has passed through the pair of rollers 903 is discharged onto the paper refeeding device. There is. Also, the transfer paper size is A4 portrait, B5
When it is vertical (or 11'), the gates 905 and 906 take the positions shown by the solid lines, and the gate 907 takes the position shown by the broken lines, and the transfer paper that has passed the pair of rollers 904 is discharged onto the paper refeeding device. The subsequent operations are the same as those for A4 and below as described above.

On the other hand, in addition to the conveyance path set for double-sided copying described above, the above-mentioned copying machine main body C is also provided with a conveyance path for composite (multiple) copying of images on one side of a transfer sheet.

That is, the above-mentioned combination conveyance path includes a pair of rollers 80
It is set from the gate 805 located on the downstream side of 4 to the paper refeeding device 900 for double-sided copying.

When performing composite copying on this transport path, regardless of the size, the game 1-805 is first moved to the position indicated by the broken line to send the fixed transfer paper to the transport path 823. Then, the gate 814 is moved to the position indicated by the broken line, and the transfer paper is sent to the pair of rollers 902. Transfer paper size is A
3 (or 17#), the gate 905 takes the position indicated by the broken line, and the paper is immediately discharged onto the paper refeeding device after passing the pair of rollers 902. When the transfer paper size is B4 (or size 41), the gate 905 is positioned as a solid line and the gate 906 is positioned as a broken line, and after passing through a pair of rollers 903, the sheet is discharged onto the paper refeeding device. Also, the transfer paper size is A4 portrait,
Gates 905 and 906 when BS vertical (or 11")
takes the position shown by the solid line, and the gate 907 takes the position shown by the broken line, and the transfer paper that has passed through the pair of rollers 904 is discharged onto the paper refeeding device.

The operations up to this point are the same as those for both sides of paper larger than A4 (or LT) as described above.

When the transfer paper size is A4 landscape (or LT or smaller), gates 905, 906, and 907 take the positions shown by solid lines, and after passing above gate 907, the paper is discharged onto the paper refeeding device. A pair of pick-up rollers 908 is operated to align the ejected transfer paper. The subsequent operations are the same as those for double-sided copying described above.

The configuration and operation of the automatic reversing document device (ARDF) 100 will be described with reference to FIGS. 2 and 3.

First, in the case of a single-sided original, the original to be copied is set on the tray 101 in the direction of arrow A with the image side facing up. The set original is fed by a paper feeding mechanism similar to the multi-manual paper feeding device.

In other words, the document is pulled in to the left by the feed roller 102, and then the paper feed roller 1 is rotated clockwise.
03 and separation roller 1 which is also rotated clockwise.
Due to 04, only the topmost document is moved to a pair of rollers 106.
It will be sent to the destination.

This automatic document feeder feeds documents in page order. The pair of rollers 106 are stopped until the document is sent, and begin rotating a little after the leading edge of the document is reached. This corrects the skew (oblique feeding) of the original.

Then, after passing the pair of rollers 107, the guide plate 123
The contact glass 203 and the conveyor belt 11 are guided by
Sent between 8. The conveyor belt 118 is a sliding roller 1
15, roller 116 and tension roller 117
It is suspended by. Original contact glass 203
The upward stopping position is determined by the number of pulses starting from when the trailing edge of the document passes the sensor 127.

When scanning of the document is completed, the conveyor belt opening roller 1
15 is rotated clockwise and the document is sent out to the left in a switchback manner. The first gate 111, which was initially in the position shown by the solid line, is displaced to the position shown by the broken line in FIG. 3(a). In other words, the state shown by the solid line shown in FIG. 3(c) is established. The leading edge of the document passes between rollers 112 and 113 and is delivered to tray 11.
Served on 9th.

In this state, the image side of the document is on the top side, so if the paper continues to be ejected, the order of the pages will be reversed. To avoid this, this device performs another reversal. That is, at the same time that the rear edge of the original is detected by the sensor 128, the roller 108 and the roller 1
13 is reversed counterclockwise. At the same time, based on this inversion signal, the second gate 110 is switched to the solid line position shown in FIG. 3(b), and the first gate 111 is also switched to the lower solid line position. In this way, as shown in FIG. 3(Q), the originals pass between the rollers 113 and 114 and are stacked on the tray 119 with the image side facing down. The same operation is repeated one after another, and the originals are stacked in the same page order as when they were first set.

In the case of a double-sided original, the first side is covered with a contact glass 203.
The process is the same as the single-sided mode described above until it is stopped at the top. When scanning of the original is completed, the conveyor belt opening roller 11
5 is rotated clockwise and the document is sent out to the left in a switchback manner. At this time, the first gate 111 is moved upward as in the case of a single-sided original, and in addition, the third gate 1-109 is also moved upward. The situation is shown in FIG. 3(d).

In FIG. 3(d), the leading edge of the document to be reversed is guided by guides 121, 122 and placed on the contact glass 22 again.
3 is sent above. The stopping position of the original on the contact glass 203 is determined by the number of pulses from the time when the trailing edge of the original passes the sensor 38.

When the scanning of the second side of the document is completed, the conveyor belt moving roller 115 is rotated clockwise to send the document to the left in a switchback manner. At this time, the third gate 109 is displaced downward, and the document passes between the rollers 12 and 113 and is stacked on the tray 119 in the state shown in FIG. 3(c).
The feeding and discharging operation of the double-sided original is completed. Thereafter, the same operation is repeated one after another, and the originals are stacked at the same page as when they were first set.

On the other hand, sorters 1000 as shown in FIG. 4 are arranged side by side on the side of the above-described image forming main body.

To this sorter 1000, recording sheets are fed out from a refeeding device for double-sided copying, which constitutes an image forming conveyance path in the image forming main body, so that the direction is changed in the direction perpendicular to the opening. . That is, in the paper refeeding device 900 of the image forming apparatus main body shown in FIG. 1, the transfer paper that has been brought to the front side (right side in the figure) with respect to the operation section in FIG. The sorting to be conveyed is provided with a discharge conveyance path as will be described later, and has excellent conveyance efficiency since sheets that have been sent in long lengths, such as A3 and B4, are sent in short lengths.

In addition, this sorter 1000 has the ability to
In other words, the orientation of the image surface can be switched immediately after image formation is completed, but first a case will be explained in which the orientation is not switched on the sorter side.

In other words, when copying in page order, the copied sheets are stacked with the image side facing down, or if the image side is facing up, they are inserted under the previous transfer sheet and placed in the same state as the original. However, the latter method is not very common due to its ease of use, and the former method is more common, so for convenience, this method is referred to as back-side paper ejection.

The above-mentioned operation of turning the top surface of the transfer sheet inside out for back side ejection is performed on the image forming main body side shown in FIG. In other words, as in the case of synthetic copying, gate 80
By switching to the position indicated by the broken line in 5, the transfer paper is transferred to the conveyance path 8.
23,826 to a pair of rollers 922, and the i-th
As shown in the figure, vertical conveyance rollers 923, 924. ．． 925, the image is sent down the sorter conveyance path 92↓ with the image surface facing down.

At this time, the pinch roller 926a, which serves as a pressure roller constituting the right-angle conveying roller 926, is retracted upwardly.

The transfer paper that has come out of the roller 925 is sent to a photo sensor 927
The leading edge is detected and stopped after being fed for a certain period of time. Next, a pinch roller 923a as a pressure roller forming the vertical conveyance roller 923°924.925,
924a and 925a are retracted so as to be separated upward, and in their place, the pinch roller 926a of the right angle conveying roller 926 is lowered to sandwich the transfer paper and convey it to the front side with respect to the paper surface shown in Figure T. be done.

As shown in FIG. 4, the transfer paper sent out from the image forming main body passes through a guide plate 1301 and is guided upward by a gate 1302. Further, as shown in FIG. 5, the gate 1104a is rotated counterclockwise, and the t-th sheet of transfer paper is fed to the bin tray 1lo1a after passing through a pair of rollers 102a and 1103a. Gates 1104b are opened for the second sheet of transfer paper, gate ↓104c is opened for the third sheet of transfer paper, and so on, and the gates are opened one after another.

1, stacked into a bin tray of 101c.

The gate 1105 for the tenth bin 1101j is always fixed at an open position.

On the other hand, in front-side discharge with the image side facing up, the transfer paper is first switched back in the image forming body in the same manner as double-sided copying, and then sent to the sorter conveyance path. The operation of conveying the transfer paper from the sorter conveyance path to the sorter is the same as in the case of back side discharge.

Sorter 1000 switches between front side and back side output.
Regarding the operation performed on the side, paper processing on the image forming main body side will be explained based on a method in which the paper is stacked on the paper refeeding device without switchback as in the case of composite copying. Since the sheet is conveyed to the guide plate 1301 with the image side facing down, the above-described operation is performed when the sheet is discharged from the back side.

In other words, the gate 1302 is located at the lower side, and the transfer paper is guided directly to the upper 10 bin sorters. In front-side paper discharge, the gate 1302 is positioned upward, and the transfer paper is first guided to the lower 10 bin sorters. At this time, the right side of the transfer paper in the figure becomes the image surface. When the sensor 1210 detects the trailing edge of the transfer paper, the rollers 1307 and 1205
, 1206 and 1207 are reversed and the transfer paper is switched back to the top 10 bin sorters.

Stacking into each bin is the same as when outputting from the back side, but
The image side is facing up on the tray.

Also, as shown in FIG. 6, in the lower 10 bin sorter, the gate 1302 is displaced upward;
The transfer paper is guided downward by a guide plate 1301 and passes through a pair of rollers 1307. - When the 11th sheet (correctly the 11th sheet since the operation is performed after the 11th bin) comes, the gate 1204a is opened and the rollers 1202a, 1
203a and is stacked on the bin tray 1201a. Thereafter, the gates 1204b and 1204C are sequentially opened, and the trays are stacked onto the trays ↓201b and 1201c.

Next, switch between front side paper output and back side paper output on sorter 1.
The operation performed on the 000 side will be explained.

In the case of back-side paper ejection, gate 1 is positioned directly above.
302 leads directly to the 10 bin sorters below. In the case of front side paper ejection, gate 1 is used as shown in Figure 5.
302 is located below, and after passing through the guide plate 1301, is first sent upward.

At this time, the image surface is on the left side of the transfer paper in the drawing. When the rear edge of the transfer paper is detected by the sensor 1110, the roller 110
2.1103 is reversed, thereby switching back the transfer paper. The subsequent operation is the same as the other stacking operations; the gate 1204 is opened, the sheets pass through a pair of rollers 1202 and 1203, and are stacked on the tray 1201.

20 such bin sorters plus 20 more
The body equipped with a bin sorter is shown in Figure 7. The additional 20 bin sorters have a similar internal configuration. Added 20 body bins.
The transfer paper is conveyed to the sorter by threading between the ten bin sorters. At this time, the gate 1302 is placed at an intermediate position as shown in FIG. 8(b). The transfer paper that has passed through the guide plate 1301 is moved horizontally as it is and is moved to rollers 1304, 1305, 13.
Pass through 06. The operation after passing through the guide plate 1303 is similar to the operation of the 20 bin sorters after the guide plate 1301.

On the other hand, the forward conveyance roller 923.924.9 mentioned above
25 and the orthogonal direction conveyance roller 926 are selectively activated or stopped by a common switching mechanism, as will be described later with reference to FIG.

In other words, in this example, A4 size paper has a density of 40 cpm (c
opy per m1nute, number of copies per minute 4
0 sheets), 27 cpm for B4 longitudinal feed, 2 for A3 longitudinal feed
It is configured as a 3 cpm machine, and after the trailing edge of the largest size paper passes the fixing roller 701, the leading edge of the paper is gripped by the forward transport roller 923.

As described above, in the forward conveyance rollers provided in the forward conveyance path and the perpendicular conveyance path,
Pinch rollers 9238, 924a, and 925a are brought into contact with or separated from opening rollers 923, 924, and 925, which are constantly rotated, at predetermined timings, thereby performing a perpendicular discharge operation with respect to the sorter.

That is, with respect to the opening rollers 923, 924, and 925 constituting the forward conveyance rollers of the forward conveyance path, pinch rollers 923a, 924a, and
925a is pressed, the Xi''I sheet is conveyed from the forward direction conveyance path to the perpendicular direction conveyance path, and when the recording sheet comes to a predetermined position, the above-mentioned opening roller 9
When the pinch rollers 923a, 924a, and 925a mentioned above are removed from the recording paper 23, 924, and 925, the application of the forward conveying force to the recording paper is stopped.

At the same time, the pinch roller 926a constituting the pressure roller is pressed against the above-mentioned opening roller 926 constituting the perpendicular conveyance roller, so that a conveyance force in the perpendicular direction is applied to the recording paper. This allows the recording paper to be sent to the sorter in a constant position at all times, while being quickly changed direction.

A configuration for performing the above-described operation is shown in FIG.

That is, in FIG. 9, the forward conveyance roller 9
Pinch roller-923a for 23,924,925
, 924a, 925a are supported by support shafts 951, 952 by elastic members 941, 942, 943 made of springs or the like.
, 953 in the pressing direction, and the pinch roller 926a for the perpendicular conveyance roller 926 is urged in the pressing direction through a support shaft 954 by an elastic member 944 made of a spring or the like. has been done.

The spindle 953 of the pinch roller 925a and the spindle 954 of the pinch roller 926a extend in directions perpendicular to each other, and the spindle 953 of the pinch roller 925a extends in directions perpendicular to each other.
A bevel gear 953a fixed to the tip of the pinch roller 926a is meshed with a bevel gear 954a fixed to the tip of the spindle 954 of the pinch roller 926a. Thereby, the rotational movement of the support shaft 953 is transmitted to the support shaft 954 side, so that both the support shafts perform rotational movement at the same time.

Further, the forward direction conveyance rollers 923, 924° 925 obtain rotational opening power from input pulleys 931, 932, 933, respectively, and the perpendicular direction conveyance roller 926 obtains rotational opening power from an input pulley 934. .

Then, the transfer paper is transported at a predetermined speed by the transport action of forward transport rollers 923, 924, and 925.
After passing the most downstream forward conveyance roller 925, the leading edge is detected by a paper detection sensor 927, and the leading edge is stopped in response to a signal from the sensor 927 so that the leading edge is aligned with a stop position 928. At the same time, the conveyance direction is changed to 90 as shown below.
You can switch degrees.

This switching operation of the conveying direction is performed by the pinch roller 9.
23a, 924. a, 925 a support shaft 95
↓, each plunger connected to 952, 953
This is performed by the suction operation of solenoids 96↓, 962, and 963. That is, each plunger solenoid 96
↓, each support shaft 951, 9 due to the suction operation of 962, 963
52, 953 are rotated through a certain angle, and as a result, the pinch rollers 923a, 924a, 925a of the forward transport rollers 923, 924, 925 are retracted to the open position and the transfer paper is stopped, and at the same time, the spindle 953 The rotational motion is transmitted to the support shaft 954 side, and thereby the pinch roller 926a of the perpendicular conveyance roller 926 is pressurized and a perpendicular conveyance force is applied to the transfer paper.

Other means such as a cam may also be used as such a transport direction switching mechanism. In this way, the transfer paper is conveyed with a 90 degree change in direction from before, and as a result, the recording paper is always in a fixed position, quickly changes direction, and is conveyed in a right-angled direction, and then sent to the sorter. It will be.

As soon as the preceding transfer paper P1 is withdrawn, the suction operation of the plunger solenoids 961, 962, and 963 is released, and the pinch roller 923a.

924a and 925a are elastic members 941, 942°943
It is pressurized by the tension of As a result, the forward conveying rollers 923, 924, and 925 are again given conveying force, and are prepared for conveying the subsequent transfer paper P2.

In this embodiment, each conveyance roller in the forward direction conveyance path has a paper conveyance speed □ which is the same as the operating process speed,
The paper conveyance speed V2 is increased in a fixed relationship with respect to the operating process speed, and the conveyance speed of the forward conveyance rollers in these forward conveyance paths is It is set based on the paper width dimension in the paper conveyance direction and the interval dimension i between each transfer paper. More specifically, as will be described later, the transfer paper with the largest difference m (m=h−i) between the paper width in the transport direction of the transfer paper and the interval i between each transfer paper is used as a reference. The paper transport speed in the forward direction is configured to be set. Further, the switching operation of the paper conveyance speed at this time is performed based on the trailing edge detection signal of the transfer paper immediately after leaving the fixing device 700.

Hereinafter, this will be specifically explained in the case of A4 horizontal feeding (shorter feeding), the case of B4 vertical feeding (longitudinal feeding), and the case of A3 vertical feeding (longitudinal feeding). Note that each transport roller in the orthogonal transport path is configured to have a paper transport speed V2 that is increased in a constant relationship to the imaging process speed.

First, when we calculate the difference m (m=h-i) between the paper width dimension in the transport direction of each transfer paper and the interval dimension i between each transfer paper, A4; m=h-i=297-165=132 (m
u) B4; m=hi=257-190=67(m
)A3 ;m=hi=297-233=64
(mm). Since the transfer paper with the largest difference m is A4, the paper conveyance speed is set based on the A4 transfer paper.

Figure 10(c), Figure 11(C) and Figure 12(C)
As shown in , in the case of A4 horizontal feed (short feed), the toner image on the drum 601 is transferred to the transfer paper and passes through the fixing device 700, where the toner image is fixed. The sheet passes through a pair of fixing sheet discharge rollers 704 and reaches a sheet detection sensor 801 .

The transfer paper conveyance speed at this time is approximately 25%, which is the same as the process speed.
The transfer speed is set to V1 on the low speed side of 0 +nm/see, and as shown in Fig. 10(C), the paper width dimension in the transfer direction of the transfer paper is 297+m, but the distance between the transfer papers is The interval i is approximately 165 m. The transfer paper passes through a pair of transport rollers 802 , and after passing through transport rollers 804 , it advances to a turn transport path 823 . At this time, the gate claw 805 has been displaced to the upper position shown by the broken line.

When the trailing edge of the transfer paper is detected by the paper detection sensor 801, the forward transport roller group starting with the transport roller 804 is switched to the higher transport speed v2. The high-speed conveyance speed (2) at this time is determined as follows.

First, the distance L1 from the leading edge of the paper to the paper stop position 928 when the paper detection sensor 801 detects the paper is the distance La(
In this example, 880 mm), the length L of the transfer paper in the conveying direction
t (210 nwn for A4 size transfer paper) and the distance Ls from the fixing roller 701 to the paper detection sensor 801 (110 m in this embodiment), L 1 =L a - L t - L s .

Furthermore, the time T2 from when the leading transfer paper P1 is detected by the paper detection sensor 801 until the leading edge reaches the stop position 928 is such that the following transfer paper P2 is
, the time Tb required for the preceding transfer paper P1 to move in the width direction over the width dimension, and the time Td at which the trailing edge of the preceding transfer paper P1 is detected by the paper detection sensor 801. T2=Tf-Tb-Td.

On the other hand, the time Tg for the subsequent transfer paper P2 to catch up with the preceding transfer paper PL due to high-speed conveyance and the time Th for the trailing edge of the subsequent transfer paper P2 to be detected by the paper detection sensor 801 are as follows: Tg=(La-2XLt-Ls )/V2Th=Tc+
(Lt+Ls)/V.

=i/V□10(Lt+Ls)/V□=(i+Lt+Ls)/V. Since the above Tf is T f = T g + T h , considering T b = (h 10 m) / V engineering T d = L s / V 1, T f = (L a 2 X L t L s)
/V 2 +(i+Lt+Ls)/V engineering. Therefore, T2 (=Tf-Tb-Td) is T2 = (La2XLtLs)
/ V z +(i +Lt+LS)/V1 (h+m)/V2-Ls/V1 = (La-2X Lt-Ls-h-m)/
V2+(i+Lt)/V□. That is, it is expressed as V2=V,X (Lt+h+m)/(i+Lt). At this time, the distance i between the transfer sheets (i FIG. 10(c)
) is about 165- as shown in h
= 297na, and by substituting the actual numerical value in this example into the above equation, we get V, = 250X (
210+297+13) / (165+210)=2
It is determined that 50X520/375 = 347 (an/5ee).

In the case of this A4 horizontal feeding, when the trailing edge of the transfer paper is detected by the paper detection sensor 80↓, each conveyance roller 804,
813,922,923,924°925.926 is
The low conveyance speed V□ is switched to the high conveyance speed v2. Note that the conveyance rollers 923, 924, 925, 9
26 is designed to be able to take only the conveyance speed v2 on the high speed side.

The high-speed conveyance speed V2 (34
When the transfer paper is conveyed at a speed of 7 mm/sec), the preceding transfer paper P1 is transferred to the first transfer paper after leaving the fixing roller 701.
As shown in Figure 2(c), the stop position 92 is reached after about 2.05 seconds.
Reach 8.

Next, the paper moves to right angle conveyance, and in about 2.94 seconds it is completely retracted to a position with a margin of about 13 mm from the succeeding transfer paper P2.

At this time, among the above-mentioned conveyance rollers, 804.813.
922, the rear end of the transferred transfer paper is the roller 922
After passing through, the conveyance speed is returned to the lower speed side of 1 yuan.

By the way, as mentioned above, the high-speed conveyance speed v2 is
The stop position 928 is reached after about 1.6↓ seconds. Then, the paper moves to right-angle conveyance, and after about 2.35 seconds, it is completely retracted to a position with a margin of about 13 nwn from the succeeding transfer paper P2. The switching to the right angle direction and the conveyance operation are the same as in the case of A4.

Furthermore, FIGS. 10(a), 11(a) and 1
Even in the case of A3 longitudinal feeding (longitudinal feeding) shown in FIG. 2(a), the fJ conveyance operation is basically the same as in the cases of A4 horizontal feeding and B4 longitudinal feeding.

That is, the transfer paper in this case is also transported at a transport speed of about 250 nwn/sec, which is the same as the image forming process speed V1, and the trailing edge of the transfer paper reaches the paper detection sensor 80.
1, the forward conveyance roller group below conveyance roller 804 is switched to a high 41M conveyance speed ■2.

The high-speed conveyance speed V2 at this time is also set to 347 m/sec, which is the same as the high-speed conveyance speed V2 in the case of A4 feeding and B4 feeding, and the preceding transfer paper P1
After leaving the fixing roller 701, it reaches a stop position 928 about 1.61 seconds later, as shown in FIG. 12(b).

Then, it moves to right-angle conveyance, and after about 2.35 seconds, it is completely retracted to a position with a margin of about ↓3 m from the transfer paper P2 following t and Z. The switching to the right angle direction and the conveyance operation are the same as in the case of A4.

Furthermore, FIGS. 10(a), 11(a) and 1
In the case of A3 vertical feeding (longitudinal feeding) shown in FIG.

In this case, the transfer paper in this case also has a conveyance speed of about 250 nwn/see, which is the same as the image forming process speed (1).
When the trailing edge of one rolled sheet is detected by the sheet detection sensor 801, the forward conveyance roller group starting from the conveyance roller 804 is switched to the high conveyance speed V2. The high-speed conveyance speed 2 at this time is also set to 347 m/see, which is the same as the high-speed conveyance speed V2 in the case of A4 feed and B4 feed, and the preceding transfer paper PL is transferred after leaving the fixing roller 701. , Figure 12(a)
The stop position 928 is reached after about 1.45 seconds, as shown in FIG. Then, the transfer paper moves to right angle conveyance, and after about 2.34 seconds, the transfer paper P2 is completely retracted to a position with a margin of about 13 on+ from the succeeding transfer paper P2. The switching to the right angle direction and the conveyance operation at this time are the same as in the case of A4 feeding and B4 feeding.

In this way, in the perpendicular discharge operation to the sorter, the paper feeding speed in the forward direction conveyance path is increased at a predetermined timing to maintain a constant relationship with the process speed, and as a result, the preceding transfer paper P1 in the forward direction conveyance path The distance between the following transfer paper P2 and the preceding transfer paper PL is set to a certain value or more.
is received at the entrance of the perpendicular transport path and sent out from there, and then the subsequent transfer paper P2 enters the entrance of the perpendicular transport path. Therefore, wrap interference between the preceding recording paper and the following transfer paper at the entrance of the perpendicular conveyance path is reliably prevented.

That is, as explained above, for any size of transfer paper, the high-speed conveyance speed (2) is determined from the width direction value of the transfer paper and the transfer paper interval value i, and is the same for any size of transfer paper. Interference can be avoided with a margin of distance of 1, and a good ejecting operation can be performed.

Furthermore, in this embodiment, at the above-mentioned transport speed, each transport roller in the forward direction transport path is set to the same paper transport speed as the image forming process speed, and each transport roller in the orthogonal transport path is set at the same paper transport speed as described above. The increased paper transport speed is also set in a fixed relationship with respect to the process speed.

This case will be explained below using A3 vertical feeding (longitudinal feeding), B4 vertical feeding (longitudinal feeding), and A4 horizontal feeding (shortward feeding).

First, let us begin with Figure 10 (,
), Figure 1 (a) and the newly added Figure 13 (a)
In the case of A3 vertical feeding (longitudinal feeding) shown in , the transfer paper has the toner image on the drum 601 transferred thereto, passes through the fixing device 700, and after the toner image is fixed here, the transfer paper is transferred to the fixing paper discharge roller. Pair 704, conveyance rollers 802, 8
04, 813, 922, etc. in sequence. The gate claw 805 has been displaced to the position indicated by the broken line in the figure,
As a result, the transfer paper is guided to the turn conveyance path 823. Further, the gate claw 814 is located at the position shown by the solid line in the figure, so that the transfer paper is guided to the turn conveyance path 826.

At this time, the transfer paper conveyance speed is set to a low conveyance speed of about 250 rrrn/see, which is the same as the image forming process speed, and the paper spacing between the transfer sheets is as shown in Fig. 10 (
As shown in a), it is approximately 233 mm.

Next, the transfer paper approaches the forward conveyance roller 923, but each of the following forward conveyance rollers 923, 924, 92
5 is also the same as the imaging process speed, approximately 250 ntn/se
The transport speed is set to V4 on the low speed side of e.

After the transfer paper P1 passes through the forward conveyance roller 925, when the leading edge is detected by the paper detection sensor 927,
In response to this signal, the tip is aligned with the stop position 928 and is temporarily stopped. As shown in Figure 13(a),
Approximately 1 minute after the rear end of the transfer paper P1 leaves the fixing roller 701
．． After 84 seconds, the conveyance direction of the transfer paper P1 changes to 9.
0' converted.

The conveyance speed of the perpendicular direction conveyance roller 926 is set to approximately 470 nrn/see, which is faster than the image forming process speed (approximately 250 mm/5ee), and approximately 0.66 seconds have elapsed since the perpendicular direction conveyance was started. Sometimes the 11th
As shown in FIG.
It is placed at a non-interference position with a margin width of r@.

This is about 2.5 seconds after the trailing edge of the preceding transfer paper P1 leaves the fixing roller 701.

At this time, the leading edge of the subsequent transfer paper P2 is
13 and the conveying roller 922, and the distance between the two transfer sheets is approximately 70 mm.

In this way, the ejection of the preceding transfer paper P1 is completed, but if the speed of the right-angle conveyance is kept at the image forming process speed, the state shown by the broken line in FIG. 13 will occur, and the subsequent This may cause interference with the transfer paper P2.

Next, Fig. 10(b), Fig. 11(b) and Fig. 13(
In the case of B4 vertical feeding (longitudinal feeding) shown in b), basically the same paper conveyance as in the above-mentioned A3 vertical feeding (longitudinal feeding) is performed. That is, each of the forward conveyance rollers 923, 924, and 925 is set to a low conveyance speed of about 250 am/see, which is the same as the image forming process speed, and after the transfer paper P1 passes through the forward conveyance roller 925, the paper is detected. When the tip is detected by the sensor 927, the tip is aligned with the stop position 928 based on the signal and is temporarily stopped. As shown in FIG. 13(b), this is about 2.06 seconds after the rear end of the transfer paper P1 leaves the fixing roller 701, and from there the conveyance direction of the transfer paper P1 changes by 90''. be done.

The conveying speed of the right angle conveying roller 926 is about 4 times faster than the imaging process speed (about 250 ny/5ee).
70 m/sec, and when approximately 0.57 seconds have elapsed since the conveyance started in the right angle direction, as shown in Fig. 11(b)
As shown, the transfer paper PL is conveyed at right angles over about 27 On+m and is placed at a non-interference position with a margin width of about ↓3m with respect to the following transfer paper P2. This is 2.64 seconds after the rear end of the preceding transfer paper P1 leaves the fixing roller 701, as shown in FIG. 13(b). At this time, the leading edge of the succeeding transfer paper P2 is located between the transport roller 922 and the forward transport roller 923, and the distance between the two transfer papers is approximately 45 mm.

In this way, the ejection of the preceding transfer paper P1 is completed, but if the speed of the right-angle conveyance is left as the image forming process speed, the state shown by the broken line in FIG. This will cause interference with the transfer paper P2.

Furthermore, even in the case of A4 horizontal feed (short feed) shown in FIG. 10(C), FIG. 11(C), and FIG. Basically, the same paper conveyance as in the case of feeding (longitudinal feeding) is executed. That is, each forward conveyance roller 923, 924,
925 is approximately 250 wr/sec, which is the same as the image forming process speed.
After the transfer paper P1 passes the forward transport roller 925, the leading edge of the transfer paper P1 is detected by the paper detection sensor 927, and the leading edge is aligned with the stop position 928 based on the signal, and once will be stopped. As shown in FIG. 13(c), this is approximately 2.68 seconds after the rear end of the transfer paper PL leaves the fixing roller 701.
From there, the transport direction of the transfer paper is changed by 90'.

The conveyance speed of the perpendicular direction conveyance roller 926 is set to approximately 470 m/see, which is faster than the image forming process speed (approximately 250 no/5ee), and when approximately 0.66 seconds have elapsed since the perpendicular direction conveyance was started. Figure 11 (c
), the transfer paper P1 is conveyed at right angles over about 31 ORIn and placed at a non-interfering position with a margin width of about 13 strokes relative to the following transfer paper P2. This is approximately 3.34 seconds after the trailing edge of the preceding transfer paper P1 leaves the fixing roller 701. At this time, the leading edge of the subsequent transfer paper P2 is connected to the transport roller 922 and the forward transport roller 92.
It is between 3 and 3.

When the preceding transfer paper P1 is substantially removed from the perpendicular conveyance path, approximately 3.3 seconds have elapsed since the trailing edge of the transfer paper PL exited the fixing roller 701, and at this time, the subsequent transfer Paper P2 is located approximately 10 mm behind. Therefore, no interference occurs between the two transfer papers. In this way, the conveying speed of the perpendicular conveying roller 926 (approximately 470 re/
5ee) is determined based on the A4 horizontal feed with the smallest transfer paper interval.

In this way, the ejection of the preceding transfer paper P1 is completed, but if the speed of the right-angle conveyance is kept at the image forming process speed, the state shown by the broken line in FIG. 13 will occur, and the subsequent This will cause interference with the transfer paper P2.

In this embodiment, by using the sorter configured as described above, the following advantages can be obtained.

The 0+ transfer paper can be taken out in the front direction, and the edge of the transfer paper can be placed in the front regardless of the size, so that the ease of taking out the transfer paper can be improved.

(2) Post-processing such as stapling and punching on the edge of the transfer paper can be easily performed, and can also be performed manually.

■Even if a jam occurs during sorting, it is easy to remove the jammed paper because the edge of the copy paper is at the front.

- Transfer paper of relatively large size, such as A3 size or B4 size, can be fed in the transverse direction, improving conveyance efficiency and enabling speedy sorting.

■Since the largest A3 size transfer paper is fed in the transverse direction and stacked on the bin tray, the width direction of the sorter can be shortened and space can be saved. By limiting the number of sheets stacked in the bin and making the bin slope more than a certain level, it is possible to further reduce the width.

■Since it can be expanded in stages, it is possible to provide a large-capacity sorter that fully meets the needs of users, and even in this case, the conveyance path of the sorter can be kept short to prevent a decline in conveyance performance.

(Effects of the Invention) As is clear from the above description, according to the present invention, the direction of the recording sheet is changed approximately perpendicularly from the image forming conveyance path of the front-operated image forming main body to the finisher. Since a discharge path is provided for the sorting to be sent out, it is possible to downsize the entire image forming apparatus including the image forming main body and the finisher. Therefore, it is possible to make the space extremely small without setting up a large operating space around the device, which was conventionally required, and the image forming device can be installed in a space-saving manner.

In addition to this, according to the present invention, the width direction value of the recording paper, which has the most severe transport conditions, is adjusted so that the distance between the preceding recording paper and the following recording paper on the forward transport path is set to a certain value or more. Since we have adopted a configuration in which the paper feed speed in the forward direction conveyance path and the paper feed speed in the perpendicular direction conveyance path relative to the paper feed speed in the forward direction conveyance path are set from the paper interval value i, The interference state due to arbor wrap between the preceding recording paper and the following recording paper in
This can be reliably prevented with a simple configuration for recording paper of any size. Therefore, high-speed and good paper grain feeding can be carried out stably and at low cost.

Further, according to the present invention, a switchback conveyance path is set in the conveyance path in the image forming main body for double-sided copying of small-sized recording paper. It is possible to improve the efficiency of copying work by shortening the transport time until paper is re-feeded.

Further, according to the present invention, since the recording paper is configured to be reversed in the recording paper transport path including the right-angle forging path, the pages 111i of the recording paper can be aligned to match the original.

[Brief explanation of drawings]

FIG. 1 is a schematic layout diagram showing the overall configuration of an image forming apparatus equipped with a paper conveyance mechanism according to an embodiment of the present invention. FIG. 2 is an automatically reversing document used in the image forming apparatus shown in FIG. Enlarged side view of paper feeder (ARDF), Figure 3 (a)
, (b), (C), and (d) are partially enlarged side views illustrating the configuration and operation of the document feeding section, reversing section, and document conveying section of the automatic reversing document feeding device, and FIG. 4 is the same as FIG. 1. FIG. 5 is a front schematic explanatory view showing a state in which a sorter is added to the image forming apparatus shown in FIG.
The figure is an enlarged front view illustrating the configuration and operation of the bin sorter located at the bottom of the sorter, and FIG. 7 is a schematic front view showing the image forming apparatus shown in FIG. 1 with an additional sorter added. Explanatory drawings, FIGS. 8(a) and 8(b) are front enlarged views for explaining the configuration and operation of the sorter loading section, and FIG. 9 is an enlarged front view for explaining the main parts of the paper conveyance mechanism according to the embodiment of the present invention. A perspective view, FIGS. 10 and 11 are plan views for explaining the paper conveyance state by the paper conveyance mechanism shown in FIG. 9, and FIGS.
FIG. 7 is a diagram for explaining the actions of the paper conveyance mechanisms shown in the figures. C...Copying machine main body, 400...Multi-stage paper feeder (PB
), 100... automatic reversing document feeder (ARDF),
821...Switchback conveyance path for small size, 823
. . . Conveyance path for composite copying, 824 . . . Switchback conveyance path for large size, 921 . . . Sorter conveyance path for forming a perpendicular direction conveyance path, 923,924.
...Forward direction conveyance roller 926...Right angle direction conveyance roller, 923a, 924a, 925a, 926
a ”・Pinch roller-11000---Sorter-ゝ＼-1~ Shape 72 figure (a) %/2 figure (-b) Shape/, 50 (δ) Zuno? Figure CC) Shape/In the field )

Claims (1)

[Scope of Claims] 1. A front-operated image forming main body section that is equipped with a forward conveyance path that conveys recording paper on which an image is formed and is ejected toward the front side and the rear side; A finisher for post-processing of recording paper is installed in parallel on the side of the image forming main body, and receives the recording paper discharged from the forward conveyance path, conveys the recording paper in a substantially perpendicular direction, and sends the recording paper to the finisher. In a paper transport mechanism of an image forming apparatus including a perpendicular transport path connected to a forward transport path, the paper transport means in the forward transport path and the paper transport means in the perpendicular transport path include: A paper conveyance mechanism for an image forming apparatus, characterized in that a common switching mechanism for selectively switching between activation and stop of a conveyance operation is provided. 2. A front operation type that is equipped with a forward conveyance path that conveys the recording paper, which is ejected after image formation is performed at a predetermined image forming process speed, toward the front and rear sides at a predetermined paper feed speed. an image forming main body section, a finisher for recording paper post-processing arranged in parallel on the side of the image forming main body section, and a finisher for receiving the recording paper discharged from the forward conveyance path and conveying it in a substantially perpendicular direction. , a paper transport mechanism of an image forming apparatus comprising a perpendicular transport path connected to a forward transport path so as to feed the recording paper to the finisher, wherein the paper transport means in the forward transport path is configured to a paper transport speed V_1 that is the same as the imaging process speed and a paper transport speed V_1 that is increased in a constant relationship to said imaging process speed;
_2 can be selected, and the paper feeding means in the forward transport path is configured to detect the difference ( A paper conveyance mechanism for an image forming apparatus, characterized in that a paper conveyance speed is set based on a recording sheet having the largest h-i). 3. In the paper transport mechanism of the image forming apparatus according to claim 2, the paper transport speed of the paper transport means in the forward direction transport path is set by a signal that detects the trailing edge of the recording paper immediately after exiting the fixing device. A paper conveyance mechanism of an image forming apparatus configured as follows. 4. In the paper conveyance mechanism of an image forming apparatus according to claim 2, the paper conveyance means in the forward direction conveyance path is configured to have a paper conveyance speed V_1 that is the same as the image forming process speed, and the paper conveyance means in the forward direction conveyance path is configured to have the same paper conveyance speed V_1 as the image forming process speed. The paper transport mechanism of the image forming apparatus is configured such that the paper transport means in the path has a paper transport speed V_2 that is increased in a constant relationship with respect to the image forming process speed. 5. In the paper transport mechanism of the image forming apparatus according to claim 2, the paper transport means in the forward direction transport path determines the size of the recording paper based on the paper width dimension h of the recording paper and the interval dimension i between each recording paper. A paper conveyance mechanism of an image forming apparatus is configured such that a paper conveyance speed can be set at each time. 6. The copying machine has a conveyance path in which the direction of conveyance of the recording paper is set from the front side to the back side with respect to the operation surface of the copying machine, and the recording paper is conveyed and circulated in this conveyance direction, and the top surface of the copying machine in the conveyance path and in a paper transport mechanism of an image forming apparatus, which is equipped with a recording paper ejection port on one side of the copying machine corresponding to a direction perpendicular to the transport direction, in the transport direction in the transport path. A switchback conveyance path for small size, which is located immediately downstream of the fixing device and is provided separately from the above-mentioned top side discharge port, and sets a conveyance path to the paper refeeding device for double-sided copying; a switchback conveyance path for large sizes, which is located downstream of the switchback conveyance path for large sizes, and sets a conveyance path branching from the discharge path leading to the discharge port on the top surface of the copying machine and heading to the refeeding device for double-sided copying; , a transport path for composite copying which sets a transport path branching from the discharge path leading to the discharge port on the top surface of the copying machine and heading towards the refeeding device for double-sided copying; and double-sided copying and composite copying for the large-sized recording paper. and a right-angled conveyance path that branches from a conveyance path set for the recording paper and converts the conveyance direction of the recording paper to a right-angled direction at a position different from the double-sided copying refeeding device. paper transport mechanism of an image forming apparatus. 7. In the paper transport mechanism of the image forming apparatus according to claim 5, the recording paper undergoes an image transfer process between it and the image forming photoreceptor in the transport path from the front side to the rear side with respect to the operation surface. The conveyance speed of the recording paper during the copying process is V_1, and the conveyance speed of the recording paper during the other copying processes is V_1.
2, the paper conveyance mechanism of the image forming apparatus is set to have a relationship of V_1<V_2. 8. The paper conveyance mechanism of the image forming apparatus according to claim 5, wherein the paper conveyance mechanism is branched from the conveyance path set for double-sided copying and composite copying of large-sized recording paper and is separate from the paper refeeding device for double-sided copying. is located on an extension of the orthogonal conveyance path that converts the conveyance direction of the recording paper to the orthogonal direction at the position, and the orientation of the image surface of the stored recording paper is such that the conveyance direction of the recording paper that is conveyed from the orthogonal conveyance path is A paper conveyance mechanism of an image forming apparatus including an inverted storage section that accommodates paper in a switched state.