JPH0867392A - Paper ejection device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a paper ejection device capable of solving various problems at the time of paper stacking on a paper ejection tray and increasing a margin against curling. [Structure] Discharge rollers 19 and 23, and this discharge roller 1
Are positioned in the vicinity of the driven rollers 20 and 24, which are pressed against the rollers 9 and 23, the discharge trays 5 and 6, and the discharge rollers 19 and 23,
Discharge pawls 21 and 25 that are rotationally switched between one of a retracted position for directing the paper discharged by the discharge rollers 19 and 23 to the discharge roller on the downstream side of the transport path and a projecting position to the discharge tray side. In the paper discharge device including the above, the protrusions 21a and 25a for giving a wavy bending to the paper are provided at the substantially central portion in the paper width direction of the surface of the discharge claw that is in sliding contact with the paper toward the paper discharge trays 5 and 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet ejecting apparatus suitable for a sheet post-processing apparatus connected to a copying machine, a facsimile, a printer or the like.

[0002]

2. Description of the Related Art A sorter is known in which a sheet is discharged to a bin by using a discharging roller and a discharging claw. This is to dispose a discharge claw along the circumferential surface of the discharge roller with a minute gap, and to discharge the paper to each bin by the discharge claw.

With this structure, the sheet is conveyed only by the inertia of the sheet after passing through the nip between the driven roller and the discharge roller, and the conveying roller is also rotated at a peripheral speed that allows for the margin. Therefore, the stackability on the bin is not so good. Moreover, the vertical direction of the leading edge of the sheet is ambiguous due to the curled state, and the preceding sheet may be pushed out, or the leading edge of the sheet may be caught due to curling of the sheet and may not be discharged smoothly.

In order to solve this problem, Japanese Patent Laid-Open No. 4-64
The description disclosed in Japanese Patent No. 571 has been proposed. In this system, the guide surface of the sorting claw that leads to the bin is overlapped with the ejection roller to obtain a sheet conveying force, and the sheet is reliably ejected to the bin.

Regarding the shape of the discharge tray, Japanese Patent Publication No. 54-27017 and Japanese Utility Model Publication No. 61-8.
In Japanese Patent No. 664, there is proposed a paper discharge tray in which a projection is formed at a substantially central position with an inclination in the discharge direction. All of these are provided to prevent the buckling and bending of the paper when the paper is discharged.

As a measure for increasing the margin against curl, as disclosed in Japanese Patent Laid-Open No. 59-99455,
There is one in which a convex portion is formed on the discharge tray.

[0007]

However, in the above-mentioned Japanese Patent Application Laid-Open No. 4-64571, not only is the driving load applied to the discharge roller increased for thick paper such as thick paper, but the leading edge of the paper is also scratched. , And streaks may occur.

Further, in Japanese Patent Publication No. 54-27017 and Japanese Utility Model Laid-Open No. 61-8664, there is a drawback in that it is not necessary to incline the protrusions, and machining is troublesome.

Further, in the above-mentioned Japanese Patent Laid-Open No. 59-99455, a convex portion must be formed on the discharge tray as a measure against curling, and conversely, the convex portion impairs the overall stackability. There was a problem that it was done.

A first object of the present invention is to eliminate problems such as curling of a sheet when ejected, pushing of the preceding sheet, and the like at the time of sheet stacking, and also to increase the margin for curling. It is to provide a sheet discharging device capable of performing

A second object of the present invention is to provide a paper ejection device which can prevent stack defects such as buckling and bending because the ejected paper is deformed into a chevron shape and is stiff in the conveying direction. To do.

A third object of the present invention is to provide a paper discharge device capable of further increasing the effects such as prevention of stack defects and increase of the margin for curling.

A fourth object of the present invention is to provide a paper discharge device capable of preventing scratches on the leading edge and scratches on the conveying surface, which may occur on thick paper, etc., and reducing the drive load of the discharge roller during paper discharge. To do.

A fifth object of the present invention is to prevent scratches on the leading edge of the paper, scratches on the conveying surface, and the like, by providing a structure for retracting the projections of the paper discharge claws when discharging strong paper such as thick paper, and to prevent the discharge roller from being damaged. An object of the present invention is to provide a paper discharge device that can reduce the driving load.

[0015]

A first object of the present invention is to provide a discharge roller which is rotationally driven to convey and discharge a sheet,
The driven roller that is pressed against the discharge roller, the discharge tray located on the lower side of the discharge roller on the downstream side, and the discharge tray for stacking the sheets, and the discharge roller are located in the vicinity of the discharge roller. In a paper discharge device having a discharge claw that guides to a discharge roller and discharges a sheet, a wavy flexure is applied to the sheet on the surface of the discharge claw that is in sliding contact with the sheet toward the discharge tray in the widthwise direction of the sheet. It is achieved by a first means provided with a protrusion for

The second purpose is to position a discharge roller that is rotated to convey and discharge a sheet, a driven roller that is pressed against the discharge roller, and a lower side of the discharge roller on the downstream side. A sheet ejecting device provided with a sheet ejection tray for stacking sheets and an ejection claw that is located in the vicinity of the ejection roller and guides the sheet from the conveyance path to the ejection roller to eject the sheet Means for forming a rib in the widthwise central portion of the discharge tray slightly upstream of the contact point between the tip of the discharge tray and the discharge tray, and forming a portion from the upstream side to immediately below the discharge roller as a substantially flat surface. Achieved by

The third object is achieved by the third means in which the projections and the ribs are located in substantially the same row in the first and second means.

The fourth object is, in the first means,
This is achieved by the fourth means which is provided so that the projection is pressed against the conveying surface and is displaceable by the surface pressure of the paper.

The above fifth object is, in the first means,
A fifth spring provided between the switching means for rotationally switching the ejection pawl and the drive means for driving the switching pawl, so as to rotate the ejection pawl even during the ejection operation of the ejection pawl. It is achieved by means of.

[0020]

In the first means, the paper sheet turn portion of the ejection pawl is provided with the projection so as to have the wavy bending in the paper conveyance direction. Problems such as pushing out when stacking paper are eliminated. Further, the margin for curl also increases.

In the second means, a convex rib is provided in the widthwise central portion of the paper discharge tray, and the rib extends to the slightly upstream side of the setting between the leading edge of the discharged paper and the paper discharge tray.
By making the portion just below the discharge roller into a substantially flat surface, the discharged paper is deformed into a chevron shape, and the waist in the transport direction is attached, so that stack defects such as buckling and bending are prevented.

In the third means, the above action is further increased by arranging the projection of the discharge claw and the rib of the discharge tray in the same row in the paper transport direction.

In the fourth means, the projection of the discharge claw is
With the structure that pressurizes the transport surface and makes it variable by the surface pressure of the paper, it prevents scratches on the leading edge and scratches on the transport surface that occur on thick paper, etc., and reduces the drive load of the discharge roller during paper discharge. it can.

In the fifth means, a spring is provided between the transport path switching means of the discharge claw and the transport path switching drive means, so that the projection of the discharge claw retracts when a strong sheet such as thick paper is discharged. As a result, scratches on the leading edge of the paper, scratches on the conveyance surface, and the like are prevented, and the driving load on the discharge roller is also reduced.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a sheet post-processing apparatus according to an embodiment, FIG. 2 is a perspective view of a sheet discharge roller and a discharge claw, and FIG. 3 shows a state in which a sheet is passed between the sheet discharge roller and the discharge claw. Top views, FIGS. 4A and 4B are explanatory views showing the configurations of the discharge roller, the discharge claw portion, and the solenoid portion, respectively, and FIG. 5 is an explanatory view showing the positional relationship between the discharge roller and the discharge tray. Is.

In these 1, 1 is an image forming apparatus, and discharge rollers 2 and 3 are provided in a discharge section. The reference numeral 4 and thereafter indicate sheet post-processing devices (sorters),
4 is a 1-bin discharge tray, 5 is a 2-bin discharge tray, and 6 is 3
Bin discharge tray, 7 is an entrance roller on the driving side, 8 is an entrance roller on the driven side, 9 is an entrance sensor, 10 is a switching claw, 11 is a reverse roller, 12 is a reverse claw, 13 is a reverse guide plate, and 14 is a conveyance. Roller, 15 strike roller, 16 reversal tray, 17 reversal sensor, 18 3-bin paper ejection sensor, 19 3-bin paper ejection roller, 20 driven roller, 21 3-bin ejection claw, 22 2-bin ejection Paper sensor, 23 is a 2-bin paper ejection roller, 24 is a driven roller, 25 is a 2-bin paper ejection claw, 26 is a 1-bin paper ejection sensor, 2
7 is a 1-bin discharging roller, 28 is a driven roller, 29 is a lumbar guide, 30 is a vertical guide roller, 31 is a vertical guide rail, 32 is a front and rear guide roller, 33 is a front and rear guide rail,
34 is a shift tray base, 35 is a tray upper surface detection sensor, 36 is an end fence, 37 is an upper entrance guide plate, 3
8 is a lower entrance guide plate, 39 is a 1-bin paper ejection guide, 50 is a shaft for 3-bin paper ejection roller or 2-bin paper ejection roller, and 51 is 3
A shaft for the bin ejecting claw or the two bin ejecting claw, 101 is a lever, and 102 solenoid.

The sorter described above is attached to the side portion of the image forming apparatus 1, and the discharge rollers 2 of the image forming apparatus 1 are provided.
There are two types of modes: a mode in which the sheets discharged by 3 are distributed and stacked in a straight state on each of the sheet discharge trays 4, 5 and 6, and a mode in which they are turned upside down.

Next, the operation will be described. Image forming apparatus 1
When the sorter is activated according to the activation information from, the inlet rollers 7 and 8 and the reversing roller 11 driven by the first drive system rotate at the same speed as the main body transport speed or slightly higher, and the second Transport roller 14 driven by a drive system, each paper ejection roller 1
9, 23, and 27 rotate at a higher speed than the conveyance speed of the image forming apparatus 1. At the same time that the front end of the paper is ejected from the ejection rollers 2 and 3 of the image forming apparatus 1, at the same time, the image forming apparatus 1 sends mode information to the sorter whether the paper should be ejected straight or reversed. Based on the above information, the paper is conveyed and discharged by different operations.

Each part will be described below along the flow of paper. (1) Straight paper discharge mode When the leading edge of the paper reaches the discharge rollers 2 and 3 of the image forming apparatus 1,
Information of the straight paper discharge mode is sent from the image forming apparatus 1 to the sorter. The sheet is guided to the inlet rollers 7 and 8 driven by the first drive system by the inlet guide plates 37 and 38. At this time, the peripheral speed of the inlet roller 7 is set to be equal to or slightly higher than the peripheral speed of the discharge rollers 2 and 3.
The paper is transported smoothly into the sorter without burdening it. At this time, the switching pawl solenoid for operating the switching pawl 10 is turned on and the switching pawl 10 is at the position indicated by the solid line, and guides the paper toward the respective paper ejection rollers 19, 23, 27 driven by the second drive system. On the other hand, when the sorter receives the mode information, each of the sheet discharge rollers 19, 23, 27 driven by the second drive system causes the leading edge of the sheet to move to the 3-bin sheet discharge roller 19 driven by the second drive system. Before reaching, the speed of the second drive system is decreased to the same speed as the first drive system, and the paper conveyed from the entrance roller 7 driven by the first drive system is transferred to the 3-bin delivery roller 19 Receive smoothly and carry it.

Next, when the trailing edge of the sheet passes through the discharge rollers 2 and 3, the trailing edge of the sheet is discharged from the image forming apparatus 1 to the discharging rollers 2 and 3.
When the sorter receives a signal that the sheet has passed through, the first and second drive systems are both speeded up so as to make a space between the sheet and the next sheet, and the trailing edge of the sheet enters the entrance roller 7, When the entrance sensor 9 detects that the vehicle has passed through 8, after a certain time,
The first drive system is returned to the original peripheral speed before the next sheet enters. At this time, the paper has been delivered to the second drive system which is driven at high speed, and has passed through the 3-bin sensor 18,
The sheet is conveyed upward so as to be discharged to each sheet discharge tray 4, 5, 6. Then, for example, when the sheet is discharged to one bin based on the information from the image forming apparatus 1, the respective sheet discharge rollers 19, 23, 27 driven by the second drive system rotate at the speed that has been increased previously. Cage, 2-bin discharge claw 25, 3-bin discharge claw 2
2 bins that operate 1 and 3 bin solenoids are off, 2
Since the bin ejecting claws 25 and the 3-bin ejecting claws 21 are in the positions indicated by the solid lines, the sheet is guided in the direction of the 1-bin sheet ejecting roller 27. Next, the paper is ejected onto the 1-bin ejection tray 4 along the 1-bin ejection guide 39. In addition, the paper is 1 bin discharge guide 3
When the backing guide 29 protruding to 9 makes a wavy backing in the transport direction, and when the rear end leaves the paper ejection roller 27, the 1-bin paper ejection roller 27 driven by the second drive system decelerates. 1 bin output tray 4 smoothly and accurately
Stocked in. The main deceleration timing is determined by the 1-bin paper ejection sensor 26 to determine whether the trailing edge of the sheet has passed. When the trailing edge of the sheet has passed, the deceleration is decelerated to a speed suitable for discharging the sheet, and After the calculated constant time, it is determined that the trailing edge of the sheet has left the 1-bin sheet discharging roller 27, the speed of the second drive system is increased again, and the next sheet is prepared to be received.

Next, for example, when the paper is discharged to the 2 bin according to the information from the image forming apparatus 1, the 2 driven by the second drive system.
The bin discharge roller 23 and the 3-bin discharge roller 19 are rotating at the speed that has been previously increased, as in the case of discharging the 1-bin.
The 3-bin solenoid that operates the 3-bin ejecting pawl 21 is off, the 3-bin ejecting pawl 21 is in the position indicated by the solid line, the 2-bin solenoid that operates the 2-bin ejecting pawl 25 is on, and the 2-bin ejecting pawl 25 is configured to eject paper. The paper is moved to the position indicated by the chain double-dashed line so as to be discharged onto the 2-bin paper discharge tray 5. Next, the paper is discharged onto the 2-bin paper discharge tray 5 along the 2-bin discharge claw 25 and the 2-bin discharge roller 23 protruding on the transport path. In addition, the paper has a wavy waist in the transport direction due to the overlap between the projection provided at the center of the 2-bin discharge claw 25 and the 2-bin discharge roller 23, and the rear end of the paper is discharged by the 2-bin discharge. Roll 2
When leaving 3, the 2-bin delivery roller 23 driven by the second drive system is decelerated, so that it is smoothly and accurately stocked in the 2-bin delivery tray 5.

The deceleration timing is determined by the 2-bin sensor 22 detecting whether or not the trailing edge of the sheet has passed. When the trailing edge of the sheet has passed, the deceleration timing is reduced to a speed suitable for ejecting the sheet, After a lapse of a fixed time calculated from the transport distance, it is determined that the trailing edge of the sheet has left the 2-bin sheet discharge roller 23, the second drive system is speeded up again, and preparation for receiving the next sheet is performed. When discharged to the 3 bin, the 2 bin solenoid is off, the 2 bin discharge pawl 25 is in the position of the solid line, the 3 bin solenoid is on, and the 3 bin discharge pawl 21 is moved to the position of the chain double-dashed line. The operation is the same as that of discharging to 2 bins except that it is present.

(2) Reversed paper discharge mode When the leading edge of the paper reaches the discharge rollers 2 and 3 of the image forming apparatus 1, the image forming apparatus 1 sends information of the reversed paper discharge mode to the sorter. The sheet is guided by the inlet guide plates 37 and 38 to the inlet rollers 7 and 8 driven by the first drive system. At this time, the peripheral speed of the inlet roller 7 is set to be equal to or slightly higher than the peripheral speed of the discharge rollers 2 and 3.
The paper is transported smoothly into the sorter without burdening it. In the reverse sheet discharge mode, since the sheet does not straddle the first and second drive systems, the transport roller 14 driven by the second drive system and each sheet discharge roller 19, 23, 27. Is rotating at a speed higher than the peripheral speed of the discharge rollers 2 and 3. At this time, the switching pawl solenoid for operating the switching pawl 10 is off, the switching pawl 10 is at the position indicated by the chain double-dashed line, and the paper is driven by the reversing pawl 12 and the first drive system to perform the reversing operation. The wedge-shaped portion composed of 11 is entered. The tip of the reversing claw 12 is set so as to overlap the reversing roller 11 and is pressed in the counterclockwise direction so that it can be rotated clockwise so as not to obstruct the entrance of the sheet. Is attached to. Therefore,
The sheet is conveyed along the reversing guide plate 13 by the conveying force generated by the reversing roller 11 and the reversing claw 12 to the reversing tray 16
Transported up.

Next, when the trailing edge of the sheet passes through the discharge rollers 2 and 3, the trailing edge of the sheet is discharged from the image forming apparatus 1 by the discharging rollers 2 and 3.
When the sorter receives this signal, the first drive system is accelerated to a speed higher than the conveyance speed of the image forming apparatus 1 and the paper is separated from the next paper. After a lapse of a fixed time after the trailing edge passes through the entrance roller 7, the first drive system is returned to the original peripheral speed before the next sheet enters. Next, the trailing edge of the paper is the reverse roller 11 and the reverse claw 12.
When it comes out of the portion in contact with, the reversing claw 12 moves from the position indicated by the one-dot chain line in the figure to the position indicated by the solid line by the rotational force. At this time, since the sheet has no carrying force, the reversing claw 1
Stop at the position slightly out of the tip of 2. next,
When the reversing sensor 17 detects that the rear end of the sheet has come out of the tip of the reversing claw 12, the reversing solenoid that drives the hitting roller 15 is turned on, and the hitting roller 15 moves from the position indicated by the solid line to the second position.
Moves to the position of the chain double-dashed line in contact with the conveyance roller 14 driven at high speed by the drive system of FIG. , 2 and 3 bins) and is discharged from each of the discharge rollers 19, 23 and 27 which are driven at high speed by the second drive system, resulting in reverse discharge. At this time, the space between the sheets is sufficiently widened so that the reversal sensor 17 does not overlap the trailing edge of the sheet and the leading edge of the next sheet. The discharge operation of the discharge rollers 19, 23, 27 to the discharge trays 4, 5, 6 is the same as in the straight discharge mode. Moreover, in addition to the sorting and stacking functions which are the same functions as the normal sorter using the paper discharge trays 4, 5, 6
The one-bin discharge tray 4 also has a doggy-tail (repeated horizontal movement) function of alternately stocking sheets at regular intervals. For this reason, the 1-bin paper ejection tray 4 has a vertical movement mechanism for maintaining the upper surface of the ejected paper at a constant height in order to improve the alignment accuracy of the paper.

Next, the paper discharge roller and the discharge claw will be described. As shown in FIGS. 2 and 3, a plurality of paper ejection rollers 19 and 23 are provided symmetrically with respect to the center line CL on the paper ejection roller shaft 50, and the paper is ejected between the rollers. The discharge claws 21 and 25 are provided so as to face each other. Protrusions 21a and 25a are provided on the shaft 51 of the central discharge claws 21 and 25 so as to face the discharge rollers 19 and 23, respectively.
As shown in (b), when the paper is discharged, the paper guide surface thereof is positioned so as to be substantially in contact with the paper discharge rollers 19 and 23. As shown in FIG. 4A, the discharge claw driving mechanism of the main discharge claws 21 and 25 includes a lever 101 fixed coaxially with the shaft 51, and a solenoid 102 fixed to one end of the lever 101. It is composed of a tension spring 103 for returning the discharge claws 21 and 25 rotated by the suction of the solenoid 102 to the original positions.

With this structure, as shown in FIG.
Is conveyed so as to have a wavy bend in the paper conveyance direction, and does not cause stacking defects such as buckling and trailing edge remaining when ejected to the paper discharge trays 5 and 6, and is reliably conveyed to the paper discharge trays 5 and 6. It is stored.

Next, the positional relationship between the paper discharge roller and the paper discharge tray will be described. As shown in FIG. 5, the discharge trays 5 and 6 are provided.
Convex ribs 5a and 6a are provided at the center of
The ribs 5a and 6a are provided on the front end of the ejected paper and the ejection roller 1
They are located slightly upstream (e in the figure) to downstream of the contact points 9 and 23 (d in the figure). It should be noted that the portion directly below the paper ejection rollers 19 and 23 is a flat surface, but this is because the shape of the rear end of the paper that abuts the end fence 106 is a substantially straight line.
This is to improve stackability in the transport direction. By adopting this configuration, when the paper comes into contact with the paper discharge trays 5 and 6, the paper is deformed into a chevron shape, and the waist in the carrying direction is attached, so stack defects such as buckling and bending can be prevented. The effects are further enhanced by arranging the protrusions 21a and 25a of the discharge claws 21 and 25 and the ribs 5a and 6a of the discharge trays 5 and 6 in the same row (on the same line) in the sheet conveying direction. Further, this configuration has a large drop between the paper discharge rollers 19 and 23 and the paper discharge trays 5 and 6, and is particularly effective when stacking a large number of sheets.

FIG. 6 is a block diagram showing an example of the projection of the discharge claw. In this example, the protrusions 21a and 25a are separate from the discharge claws 21 and 25, and the protrusions 21a and 25a are different from each other.
The position of the sheet is variable by the surface pressure of the sheet via the spring 40.

FIG. 7 is a constitutional view showing another example of the projection of the discharge claw. In this example, the projections 21a and 25a are integrated with the discharge claws 21 and 25, and the elasticity of the material itself is used to
After all, it is variable depending on the surface pressure of the paper. in this way,
By adopting the retracting structure of the protrusions 21a and 25a,
It is possible to prevent scratches on the leading edge, scratches, increase in load on the transport drive unit, and the like for strong paper such as thick paper.

In FIG. 8, conversely, the protrusions 21a and 25a are provided.
The evacuation is performed by rotating the ejection claws 21 and 25 themselves. Lever 107 and solenoid 10
Since the pulling spring 105 is provided between the two to allow retreat even when the solenoid 102 is attracted, it is possible to prevent scratches on the leading edge of the sheet, scratches, an increase in the load on the transport drive unit, and the like.

[0041]

According to the first aspect of the present invention, the sheet turn portion of the discharge claw is provided with a projection and has a wavy flexure in the sheet conveying direction. Therefore, it is possible to eliminate problems such as pushing out the previous sheet when the sheets are stacked. Further, the margin for curl can be increased.

According to the second aspect of the present invention, a convex rib is provided in the central portion in the width direction of the paper discharge tray, and the rib extends to the slightly upstream side of the setting of the leading end of the discharged paper and the paper discharge tray. And, by making it a flat surface in the part directly below the discharge roller, the discharged paper is deformed into a mountain shape, and the waist in the transport direction is attached, so it is possible to prevent stacking defects such as buckling and bending. You can

According to the third aspect of the present invention, the above-mentioned action can be further enhanced by arranging the projection of the discharge claw and the rib of the discharge tray in the same row in the paper transport direction.

According to the fourth aspect of the present invention, the projection of the discharge claw is configured to press the conveying surface and to be variable by the surface pressure of the paper, so that the leading edge scratches and the conveying that occur on the thick paper or the like are conveyed. It is possible to prevent scratches on the surface and reduce the drive load of the discharge roller when discharging the paper.

According to the fifth aspect of the present invention, by providing a spring between the transport path switching means of the discharge claw and the transport path switching drive means, the projection of the discharge claw is formed when a strong sheet such as thick paper is discharged. The retracted structure prevents scratches on the leading edge of the paper, scratches on the conveyance surface, and the like, and also reduces the drive load on the discharge roller.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a sheet post-processing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a sheet discharge roller and a discharge claw of the sheet post-processing apparatus according to the exemplary embodiment of the present invention.

FIG. 3 is a top view showing how a sheet is passed between a sheet discharge roller and a discharge claw of the sheet post-processing apparatus according to the exemplary embodiment of the present invention.

4A and 4B are configuration diagrams showing an example of a discharge claw driving mechanism of the sheet post-processing apparatus according to the embodiment of the present invention.

FIG. 5 is a front view showing the positional relationship between the paper discharge rollers and the paper discharge tray of the paper post-processing apparatus according to the embodiment of the present invention.

FIG. 6 is a configuration diagram illustrating an example of a protrusion of a discharge claw of the sheet post-processing apparatus according to the exemplary embodiment of the present invention.

FIG. 7 is a configuration diagram showing another example of the protrusion of the ejection claw of the sheet post-processing apparatus according to the embodiment of the present invention.

FIG. 8 is a configuration diagram showing another example of the ejection pawl drive mechanism of the sheet post-processing apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 5, 6 Paper ejection tray 5a, 6a Rib 19,23 Paper ejection roller (ejection roller) 20,24 Driven roller (driven roller) 21,25 Ejection claw 21a, 25a Protrusion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Minoru Hattori 2-28-24 Izumi, Higashi-ku, Nagoya, Aichi Prefecture, Yokota Building, Ricoh Elemex Co., Ltd. 24 Yokota Building Ricoh Elemex Co., Ltd.

Claims (5)

[Claims] 1. A discharge roller that is rotationally driven to convey and discharge sheets, a driven roller that is pressed against the discharge roller, and a stack located below the discharge roller on the downstream side. A paper ejection device having a paper ejection tray and a paper ejection pawl that is located near the paper ejection roller and guides the paper from the conveyance path to the paper ejection roller to eject the paper. A sheet ejecting apparatus, wherein a protrusion for imparting a wavy bending to a sheet is provided at a substantially central portion of the surface of the ejecting claw which is in contact with the sheet in the sheet width direction. 2. A discharging roller that is rotationally driven to convey and discharge the paper, a driven roller that is pressed against the discharging roller, and a stack located below the discharging roller on the downstream side. In a paper discharge device having a paper discharge tray and a discharge claw that is located near the discharge roller and guides the paper from the conveyance path to the discharge roller, and discharges the paper, the front end of the discharged paper and the discharge A sheet discharging device, characterized in that a rib is formed in a widthwise central portion of the discharging tray extending slightly upstream of a contact point with the sheet tray, and a portion extending from the upstream side to directly below the discharging roller is substantially flat. 3. The sheet ejection device according to claim 1, wherein the protrusions and the ribs are located in substantially the same row. 4. The sheet ejection device according to claim 1, wherein the protrusion is provided so as to be pressed against a conveyance surface and displaceable by a surface pressure of the sheet. 5. The discharging claw according to claim 1, wherein the discharging claw is rotated between the switching means for rotating the discharging claw and the driving means for driving the switching means even during the discharging operation of the discharging claw. A paper ejection device having a spring for enabling the paper ejection.