JPH0948557A - Sheet aftertreatment device, and image forming device equipped with it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet aftertreatment device which can raise a tray without causing a lock condition with simple structure, and an image forming device equipped with it. SOLUTION: At binding operation, a shifting discharge roller 33 retained by a rotation guide 31 is separated from a discharge roller 32 and a pair of rollers are brought into such condition that the sheet discharge is impossible, by rotating the rotation guide 31 into the first position by a rotation means. Moreover, at discharge of sheets, the shifting discharge roller 33 is welded by pressure to the discharge roller 32 by rotating the rotation guide 31 into the second position, and also this device prevents sheets from penetrating from upper space by blocking the upper space of the discharge port 50 with the shielding part 31a provided at the rotation guide 31. This is so arranged that the sheet does not get caught by the shielding part 31a forming the same face as the upper regulating member 27, when blocking the upper space of the discharge port 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus for performing post-processing such as binding operation for sheets on which images are formed by an image forming apparatus, and an image forming apparatus including the same.

[0002]

2. Description of the Related Art A conventional sheet post-processing apparatus includes a first tray for supporting an upstream side portion of a sheet discharged from a discharging means and a sheet having an upstream side portion supported by the first tray. Some of them are provided with a second tray that can move up and down with respect to a first tray that supports the downstream side portion, and a sheet post-processing apparatus having such a structure is disclosed in, for example, Japanese Patent Laid-Open No. 1-313261. There is something to be done.

And, such a sheet post-processing apparatus is
As shown in FIG. 21, a pair of moving means composed of a discharge roller 32 disposed inside the discharge port 50 and a movable discharge roller 33 provided so as to be movable in the vertical direction, and rotating while sandwiching the sheet S. The sheet S is discharged to the second tray T by the roller pair 32A.

In the figure, 27 is an upper regulating member, 27a is a lower regulating member, and these upper and lower regulating members 27, 27a respectively form the upper wall surface and the lower wall surface of the discharge port 50, and the sheet S. And a regulating means for regulating the movement of the sheet S by making contact with the inclined end which is the upstream end of the sheet S. Further, 38 is a staple tray which is a first tray.

[0005]

By the way, the sheet post-processing apparatus disclosed in this publication has a second tray for the first tray.
The tray is composed of one stage, and since the stopper for the already stacked sheets and the like is not provided at the upstream end of the second tray, when the first tray is moved above the sheet discharging unit (discharge port), The stacked sheets may fall onto the second tray, and may be locked by being sandwiched between the ceiling of the opening of the first tray and the second tray.

For this reason, the blocking member for closing the opening of the first tray is installed at a position where the guide member supporting one of the moving means swings to open and close to prevent the sheets from being stacked and conveyed. Further, when the sheets stacked on the second tray slide up and down along the regulating means, the guide member is used as a part of the regulating means so that it does not open and close due to the vertical movement of the sheets. Requires a stopper member.

Therefore, it is an object of the present invention to provide a sheet post-processing apparatus and an image forming apparatus including the same, which can reliably prevent the sheet from entering the discharge port with a simple structure. .

[0008]

According to the present invention, there is provided a main body for carrying out post-processing such as sheet binding, a discharge port formed on a side wall surface of the main body for discharging a sheet, and an inclined surface mounted on the wall surface. A sheet post-processing apparatus having a vertically movable tray for stacking sheets discharged from the discharge port and forming a top wall surface of the discharge port and sheets stacked on the tray. An upper regulating member that abuts the inclined end of the sheet, a roller pair that rotates in a state of sandwiching the sheet and ejects the sheet from the ejection port, holds one roller of the roller pair, and ejects the sheet when ejecting the sheet. A rotatable shielding member having a shielding portion that closes the upper space of the outlet to prevent the sheet from entering through the upper space; and the shielding member, the one roller when the binding operation, the other roller While rotating the roller pair is separated from the la in a first position to a sheet discharging disabled state,
A second block that closes the upper space of the discharge port in a state in which the one roller is brought into pressure contact with the other roller at the time of sheet discharge and the shielding part forms the same surface as the upper regulating member.
And a turning means for turning it to a position.

Further, according to the present invention, a discharging means for discharging a sheet, a first tray for supporting an upstream side portion of the sheet discharged by the discharging means, and an upstream side portion for supporting the first tray. A second tray that can move up and down with respect to the first tray that supports the downstream side portion of the stacked sheets, and the sheets stacked over the first tray and the second tray. A pair of moving means for moving to the tray, a restricting means for restricting the upstream end of the sheets stacked on the second tray, and one of the moving means are rotatably supported, and at the first position. The pair of moving means are spaced from each other to stack the sheets on the first tray and the second tray, and at the second position, the pair of moving means are in pressure contact with each other.
A sheet post-processing apparatus having a guide member configured to discharge a sheet to the second tray, the guide member being the first tray when the guide member is in the second position. Is closed, and is on the same plane as the regulating means.

Further, the present invention can be applied to an image forming apparatus including an image forming section and a sheet post-processing apparatus for post-processing a sheet on which an image is formed by the image forming section. Is.

Based on the above construction, when the binding operation is performed, the shield member is rotated to the first position by the rotating means so that one roller of the roller pair held by the shield member is separated from the other roller. Then, the roller pair is set in a state in which the sheet cannot be discharged. Further, when the sheet is discharged, the shielding member is rotated to the second position, one roller is brought into pressure contact with the other roller, and the shielding portion provided on the shielding member closes the upper space of the discharge port. Prevent the sheet from entering from the space. Further, when the upper space is closed, the shielding part forms the same surface as the upper regulating member so that the sheet is not caught.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the internal structure of a copying machine which is an example of an image forming apparatus to which the present invention can be applied. In the figure, 1 is a sheet post-processing apparatus main body of the present invention,
Reference numeral 100 is a copying apparatus main body, 200 is a cassette for stacking a plurality of sheets of different sizes, and 300 is an original document feeder (hereinafter referred to as ADF) for automatically feeding an original document.

First, in the copying apparatus main body 100, 10
Reference numeral 1 denotes a platen glass on which a document is loaded; 103 and 104 each a scanning reflection mirror (scanning mirror) for changing the optical path of the reflected light of the document; 105 a lens having focusing and zooming functions; A first scanning mirror having an illumination lamp and a mirror for reading the read original;
Reference numeral 107 is a registration roller, 108 and 110 are photosensitive drums and pressure rollers, 111 is a conveyor belt that conveys an image-recorded recording sheet to the fixing side, and 112 is a fixing device that thermocompresses the conveyed recording sheet.

Denoted at 113 and 117 are conveying rollers for conveying the recording sheet, 114 is a flapper for switching the conveying direction of the conveyed recording sheet, and 115 is a conveying roller for conveying the recording sheet toward the sheet post-processing apparatus 1. Reference numeral 116 is a reversing path for reversing the front and back of the recording paper, 118 is a conveyance roller for conveying the paper from the paper feed cassette to the photosensitive drum unit, 1
Reference numerals 19, 120, and 121 are rollers, a manual feed tray, and a separation pad that convey the paper from the manual feed unit. 12
2, 123 and 125 are lasers and polygon mirrors for forming an image on the photosensitive drum, mirrors for changing the optical path, and 124 is a motor for driving the polygon mirror 123.

Reference numeral 200 denotes a paper feed cassette that stacks sheets of each size according to the type and supplies the sheets to the main body according to the type from a signal from the copying machine main body 100. It is an intermediate roller that delivers the paper pulled out from above.

By the way, the surface of the photosensitive drum 108 is composed of a photoconductor and a seamless photoconductor using the conductor, and the drum 108 is rotatably supported and operates in response to the pressing of the copy start key. A main motor (not shown) starts rotation in the direction of the arrow in the figure. When the predetermined rotation control and the potential control processing (pre-processing) of the drum 108 are completed, the original placed on the original table glass 101 is illuminated by an illumination lamp integrated with the first scanning mirror 106, and the original is illuminated. The reflected light passes through the lens 105 via the scanning mirrors 103 and 104 and forms an image at the light receiving element inside the lens unit.

Here, the reflected light image from the original is converted into an electric signal by the light receiving element and sent to an image processing section (not shown), while the image is processed by the user.
After the predetermined data processing received by the main body is performed, the data is sent to the laser 112. Then, the electric signal subjected to the data processing is converted into light by the laser unit 112, and then converted to a polygon mirror 123 and a mirror 125.
Is reflected by the toner to form an electrostatic latent image on the photosensitive drum 108, visualized by toner, and transferred onto a transfer paper as described later.

The transfer paper set in the cassette 200 or the manual feed tray 120 is fed by the paper feed rollers 118,
119, 201, and 202 feed the inside of the copying apparatus main body 100, and the registration roller 109 feeds it toward the photosensitive drum 108 at accurate timing so that the leading edge of the latent image and the leading edge of the transfer sheet are aligned with each other. Then, the photosensitive drum 1
When the transfer paper passes between the roller 08 and the roller 110, the toner image on the drum 108 is transferred onto the transfer paper.

After this, the transfer paper is separated from the drum 108, guided to the fixing device 112 by the conveyor belt 111, and transferred by pressing and heating. Then, the transfer paper (hereinafter referred to as a sheet) on which an image is formed in this manner is advanced toward the paper discharge roller 115 by the flapper 114, and is discharged to the sheet post-processing apparatus 1 with the printing surface facing upward. It has become.

On the other hand, in the ADF 300, 301 is a stacking tray on which a document bundle 302 is set.
5 and the entire surface of the belt 306, the sheet is conveyed to the exposure position of the original table glass 101 through the paths I to II, and then stopped to prepare for the start of the copying operation.

After the copying is completed, the original is sent to the path VI by the large conveyance roller 307 via the path IV, and is further returned to the upper surface of the original bundle 302 by the paper discharge roller 308.
Reference numeral 309 denotes a recycle lever for detecting one cycle of the document.
When the originals are sequentially fed and the trailing edge of the final original falls through the recycle lever 309 and falls under its own weight, one cycle of the original is detected.

On the other hand, when a two-sided original is used, the original is temporarily passed through the path I,
A switching flapper 31 that is guided from II to III and is rotatable there.
By switching to 0, the leading edge of the document is guided to the path IV. The document is conveyed onto the document table glass 101 by the conveyance belt 306 through the path II by the conveyance roller 305 and stopped. That is, the document is reversed by the large conveying roller 307 along the route of the paths III to IV to II.

By the way, a stopper member 2 is provided on the upper portion of the sheet post-processing apparatus 1. When the sheet post-processing apparatus 1 is connected to the copying apparatus main body 100, the stopper member 2 serves to prevent the copying apparatus main body 100 from moving. It is positioned and attached to a hold portion 133 formed on the side surface. Further, a folding machine unit or a mounting base 70 is formed under the sheet post-processing apparatus 1, and casters 80 are movably mounted on the base 70.

Therefore, when performing jam processing near the paper discharge section of the copying apparatus main body 100 or jam processing at the transfer section of the sheet post-processing apparatus 1 and the copying apparatus main body 100,
It is easy to rotate the stopper member 2 in the X direction shown in FIG. 2 to release the engagement with the hold portion 133, and then move the sheet post-processing apparatus 1 horizontally to separate the copying apparatus main body 100 from each other. To be able to do.

On the other hand, the image-formed sheet is conveyed to either the sheet post-processing device 1 or a folding device (not shown) provided inside the mounting base 70 according to the subsequent processing. There is.

That is, when processing a sheet by the sheet post-processing apparatus 1, the upstream side end of the first flapper 3 on the side closer to the copying apparatus main body 100 shown in FIG.
By positioning the upstream end of the second flapper 4 on the downstream side of the non-wrapper 3 in the upward direction, the sheet is sent to the first transport path 6 through the roller pair 5, and is further transported to the downstream side from the first transport path 6. Will be available. When the sheet is transported to the folding device, the upstream end of the first flapper 3 is positioned upward as shown in FIG. It is sent to the folding device located at the end of the direction.

By the way, in the figure, 8 is a second transport path (buffer path), 9 is a buffer roller, and 14 and 1.
Numerals 5 and 16 are buffer rollers, and numerals 10, 11, 12, and 13 are sheet detection sensors, which perform detection of a passing sheet and detection of a staying sheet. Reference numeral 17 is a first discharging roller, 18 is a pressing roller, and 19 is a discharging alignment belt, which is sandwiched between the first discharging roller 17 and the pressing roller 18 to rotate, and as a belt detachment prevention measure, a central portion on the inner side of the belt. An endless rib (not shown) is provided in the vicinity, and is engaged with the first discharge roller 17 to rotate.

Reference numeral 21 is a width-bending plate for aligning the sheets at the time of aligning the sheets. Reference numeral 20 denotes an abutting plate, which is configured so as to have a home position for sequentially stacking sheets and a retracted position for moving the stapler 22 back and forth.
When changing the position of, the contact plate 20 in the same phase as the stapler 22 can be rotated to the position shown by the broken line and retracted.

By the way, in the present embodiment, the alignment of the sheets in the width direction is performed by the width aligning guide 21 shown in FIGS. Further, the stapler 22 is configured to move within a range indicated by an arrow in FIG. 3 and perform stapling so that sheets are bound at two positions, one at the front side and one at the back side. Although the description of the operation of the stapler 22 is omitted here, the stapler 22 itself has almost the same configuration as that of a commercially available electric (solenoid) or motor-driven automatic stapling apparatus. To bind the sheets. 3 and 4, reference numeral 21a is an alignment reference plate.

On the other hand, in FIG. 2, reference numerals 23, 24 and 25 are first trays for stacking sheets discharged from the discharge port 50 formed on the side wall surface 1a of the sheet post-processing apparatus main body 1. , Second and third trays, and 26 is a tray unit in which these first, second and third trays 23, 24 and 25 are attached in the vertical direction and in a state of being inclined toward the main body 1 side. Here, this tray unit 26
Is attached to the side wall surface 1a of the sheet post-processing apparatus main body 1 so as to be movable in the vertical direction, and is also moved in the vertical direction by a drive source (not shown) built in the lower portion thereof.

By the way, in FIG. 5, reference numeral 31 is a rotation guide which is a shielding member or a guide member, which rotatably holds the movable discharge roller 33 which is one of the rollers forming a roller pair, and at the time of discharging the sheet, Cam 3 shown in FIG.
When the drive source M rotates in the direction of the arrow in the figure, the drive source 5 rotates downward about the rotary shaft 31a as a fulcrum, and the movable discharge roller 33 is pressed against the discharge roller 32 as shown in FIG. To move to.

The cam 35 and the drive source M constitute drive means. In addition, this rotation guide 31
9 in the later-described staple mode in the staple mode.
As shown in FIG. 7, the movable discharge roller 33 is moved away from the discharge roller 32 by rotating upward to move the sheet to the first position where the sheets are stacked over the first, second and third trays 23, 24 and 25 and the staple tray 38. The roller pair 32A is moved from the sheet dischargeable state to the sheet discharge impossible state.

Further, the rotation guide 31 is provided with a notch portion 271 of an upper regulating member (hereinafter referred to as an upper snowboard guide) 27.
The sliding surface 31b is a shielding portion that closes the notch 271 so that the sliding surface 31b closes the cutout portion 271 when the sliding surface 31b rotates downward and moves to the second position. Here, a plurality of ribs 311 are formed in the vertical direction on the front surface of the sliding surface 31b that comes into contact with the sheet, as shown in FIG. By having such ribs 311, when the tray on which the sheets are stacked moves up and down, the sheets become slippery and are not caught.

By the way, although similar ribs are formed on the front surfaces of the upper snow guide 27 and the lower regulating member (hereinafter referred to as the lower snow guide) 27a, when the rotation guide 31 is rotated downward, a sliding surface is formed. The rib 311 of 31b and the ribs of these snowboard guides 27, 27a are formed on the same plane.

Then, by configuring in this way,
The sliding surface 31b of the rotation guide 31 is connected to the upper slooze guide 27.
It is possible to use it as an extension surface of the above, and there is no need to expand and contract the upper snowboard guide 27 or to make another snowboard guide appear on the extension surface of the upper snowboard guide 27, and the structure can be simplified. ing. Further, as shown in FIG. 7, by utilizing the sliding surface 31b of the rotation guide 31 as a part of the sheet placing surface, the space between the tray 23 and the tray 24 can be narrowed.

By the way, the rotation guide 31 is adapted to rotate in the direction shown by the arrow in the figure in the staple mode described later.
When the tray 1 rotates, the tray 24 on which the sheets S are stacked
If the sheet S is not located above the lower end 27b of the upper snowboard guide 27, the staple tray 38
Will fall in the direction of.

Therefore, in order to perform stapling without dropping the sheets S, the distance between the trays 23 and 24 needs to be equal to or more than the distance from the maximum stacking surface of the tray 23 to the lower end 27b of the upper saw guide 27. However, in the present embodiment, the operation mode is limited, and for example, when the sheet S is discharged to the first tray 23 as shown in FIG. Only non-staple mode is performed.

Then, by configuring in this way,
The sliding surface 31b of the rotation guide 31 is connected to the upper slooze guide 27.
Can be used as a part of
It is possible to lower the second tray 24 on which the trays are stacked below the lower end of the upper snow guide 27, reduce the space between the trays 23 and 24, and reduce the size of the tray unit 26.

On the other hand, in FIG. 5, reference numeral 30 denotes a stopper, which is rotated about the rotation shaft 30a as a fulcrum when the tray is moved,
When the tray 24 passes through the discharge port 50 by closing the discharge port 50 by the shutter portion 30b formed at the upper end as shown by the solid line in FIG. 8, the sheets S stacked on the tray 24 are discharged from the discharge port 50. This is to prevent backflow to the. When the sheet is discharged, the stopper 30 rotates in the Y direction shown in FIG. 5 to open the discharge port 50, and in the staple mode described later, FIG. As shown in FIG. 3, the rotation guide 31 is rotated in the direction of releasing the discharge port 50, similarly to the rotation guide 31.

Further, in FIG. 5, reference numeral 34 is a roller guide for guiding the discharged sheet S to the tray 24, and the lower end portion is pivotally supported between the lower drainage guide 27a and the discharge port 50 to rotate. It has a horizontal arm 34a and a vertical arm 34b that is erected so as to stand upright at substantially right angles to the horizontal arm 34a.

The roller guide 34 is urged in the direction of arrow A in FIG. 5 by the spring 37 attached to the horizontal arm 34a, and in the staple mode, as shown in FIG. It is held at a position (hereinafter referred to as a first position) where the same surface as 27a is formed.

Then, in this way, the lower sinker guide 27
By forming the same surface as “a”, even when the inclined end of the sheets Sa stacked on the tray 24 is curved upward in the staple mode, the inclined end of the sheet Sa is not inclined.
7a and the discharge roller 32 are prevented from being caught.

In this embodiment, the vertical arm 3
A locking claw 35 is provided on the upper end of 4b so as to project outward, and when the roller guide 34 is held at the first position, the locking claw 35 projects above the tray 24. It has become. By projecting the locking claws 35 above the tray 24 in this manner, the upper end of the sheet S can be prevented from exceeding the point G even when the inclined end of the sheet S is curved upward, and the next sheet is It is possible to prevent the sheet from being caught and jammed when it comes out, and from becoming a load when the width aligning guide 21 is operated to perform the alignment to deteriorate the integrity.

By the way, the roller guide 34 is adapted to swing in conjunction with the rotation guide 31 via a link 36. That is, as shown in FIG. 5, when the rotation guide 31 rotates downward and pushes down the upper arm 36a of the link 36, the link 36 rotates downward with the rotation shaft 36b as a fulcrum, and accordingly, the link 36. The lower arm 36c pushes down the horizontal arm 34a of the roller guide 34.

When the horizontal arm 34a is pushed down in this way, the roller guide 34 swings while extending the spring 37, and the tip of the locking claw 35 moves toward the inside of the main body 1 at least from the front end of the discharge roller 32. It is designed to be retracted to the position where it has entered (hereinafter referred to as the second position).

By retracting the roller guide 34 in this way, it is possible to prevent the sheet S from being caught between the roller guide 34 and the discharge roller 34 when the sheet is discharged, and to reliably discharge the sheet S. can do.
Further, as shown in FIG. 10, it is possible to form a flank shown by a slanted line I between the roller guide 34 and the lower slats guide 27a, so that the discharged sheet S can be smoothly guided to the tray 24. You can do it.

On the other hand, when the rotation guide 31 is rotated upward, the roller guide 34 returns to the first position while rotating the link 36 upward by the restoring force of the spring 37. When the roller guide 34 returns to the first position in this way, the flank I is not formed, so that the sheet S can be prevented from being caught in the staple mode.

Next, the operation of the sheet post-processing apparatus having the above structure will be described.

For example, when a sheet is discharged without stapling, the first, second and third trays 23, 24, 2 are
5 is directly discharged. FIG. 11 shows a case where the sheet is discharged to the second tray 24.

When the user selects the non-staple mode, the cam 35 (see FIG. 6) causes
As shown in FIG.
Is rotated to a position where it is pressed against the discharge roller 33. Note that, at this time, the stopper 30 rotates in the Y direction and stops. Further, the roller guide 34 is held at the second position by the rotation guide 31 and the link 36, and the locking claw 35 is retracted to the inside of the main body from the front end of the discharge roller 32.

The sheet discharged from the copying apparatus main body 100 in this state is passed through the conveying path 6 shown in FIG. 2 to the roller pair 5 and 17, and further discharged to the downstream side by the roller pair 5 and 17. After that, it is directed toward the tray 24 by the rotation guide 31, is discharged from the discharge port 50 through the discharge rollers 32 and 33, and is sequentially stacked on the tray 24.

When the sheet is discharged, the sheet S may be charged depending on the state of the sheet S or the coefficient of friction between the sheets S may be high, resulting in poor ejection, but the roller guide 34 is at the first position. The sheet is discharged without being caught by the discharging roller 32, and as shown in FIG.
Relief portion I formed between the lower part and the lower snow guide 27a
And is smoothly loaded on the tray 24.

On the other hand, when a large amount of normal sheets S are to be taken, first, the paper presence sensors 23a, 24a and 25a (FIG. 2) installed in the first, second and third trays 23, 24 and 25 are provided.
After confirming that there is no sheet left on the trays 23, 24, and 25, the tray unit 26
The first tray 23 is moved to a predetermined position for receiving the first sheet.

Further, when the number of stacked sheets reaches a fixed number, the tray unit 26 descends to a position where the upper surface of the stacked sheets is substantially the same as the surface receiving the first sheet. When the above operation is repeated and it is detected that the maximum amount of sheets has been stacked in the tray, a stop signal is issued to the copying apparatus main body 100 to temporarily stop the sheet discharge.

Next, the tray unit 26 is the second tray 2
In order to stack the sheets on the sheet No. 4, the sheet is lowered to a position where the first sheet on the second tray 24 is set to be stacked. Thereafter, the copying operation is restarted by the copying apparatus main body 100, and the stacking of sheets is restarted. After that, the same operation as described above is repeated until the tray 24 is fully loaded. The third tray 2
When sheets are stacked on the first tray 23, the second tray
This is the same as when moving to the tray 24.

By the way, in the present embodiment, the copying apparatus main body 100 is of a digital type, and such copying apparatus main body 100 is composed of a scanner section for reading an image of a document and a printer section for reproducing the image. It is also possible for each to operate independently. That is, in the scanner section, the original is illuminated by a lamp, and the reflected light is decomposed into small dots (pixels) by the light receiving element and at the same time converted into an electric signal according to the light and shade of the original (photoelectric conversion). Based on the electric signal sent from the unit, the drum is irradiated with a laser beam to form an electrostatic latent image on the drum, and a copy image is formed through developer, transfer and fixing.

Therefore, by connecting the interface 500 to the digital copying machine as shown in FIG. 1, the signal of the original read by the scanner unit is transferred to another facsimile 501.
Alternatively, it is also possible to transfer the electric signal received from another facsimile 501 to the printer unit through the interface 500 and display the image on the transfer paper. Similarly, an image signal received from a computer device 502 such as a personal computer can be sent to a printer unit through an interface 500 to be copied onto a transfer sheet, or an image read by a scanner unit can be taken into the personal computer through an interface 500. You can do it.

As described above, in the current digital copying machine, the original sent from the ADF 300 and the original table glass 10 are used.
1. Not only is the original placed on top read and copied, but also through the interface 500,
It can be used as a facsimile or as a printer for a personal computer.

By the way, in order to use the apparatus 100 as described above, the sheets are sorted into different trays and stacked, or each tray is numbered according to the user's request so that the user can select the sheets. Sheets need to be stacked on the tray.

For this reason, in this embodiment, for example, the output paper of the facsimile is used for the first tray 23 and the second tray 2 is used.
The output paper from the personal computer is placed on the sheet 4, and the output paper in the copy mode is placed on the third tray 25. Then, the operation of discharging the sheet to each tray in this way will be described.

First, description will be given of the case where the sheets S in the copy mode are stacked from the state where a certain number of output sheets from the personal computer shown in FIG. 12 are received, that is, the case where the third tray 25 is used.

When the third tray 25 is used while receiving a certain number of output sheets from the personal computer, the tray unit 26 descends and moves to a position for receiving the first sheet of the third tray 25. This operation is the same as that in the copy mode, except that the tray is lowered even if the number of stacked sheets in the tray is not the maximum.

Next, description will be given of a case where the output paper of a personal computer, such as a facsimile, is stacked on the second tray 24, that is, the first tray 23 is used.

While the sheets are stacked on the second tray 24,
The tray unit 26 moves up to stack sheets on the first tray 23. At this time, the stopper 30 is rotated as shown in FIG. 8 to prevent the sheet S from entering the space of the F portion shown by the diagonal lines in FIG. 5, and the shutter portion 30a closes the space of the F portion. The sheet 24 can move upward with the sheets S stacked. The contact surface of the shutter portion 30a with the sheet includes the sliding surface 31b of the rotation guide 31 (see FIG. 6) and the lower snow guide 27a.
Similarly, the sheet S has a rib shape so as to be slippery.

With such a structure, the sheet S can pass through the discharge port 50 without flowing backward, so that the tray 24 can move upward with the sheets S stacked. Becomes

The operation described above is an operation for moving from the second tray 24 to the first tray 23, but the same applies regardless of which tray is started.

Next, the stapling operation of the sheet post-processing apparatus will be described.

First, at the time of staple sorting in which stapling is performed to make a copy, the sheets are not directly stacked on the stacking trays 23, 24 and 25, but first, the staple tray 38 in FIG.
To load.

When the staple sort mode is selected by the user, the rotation guide 31 rotates upward to the first position as shown in FIG. 9, but when the rotation guide 31 rotates in this manner, the rollers are rotated. The guide 34 is held by the spring 37 in a position flush with the lower snow guide 27a, and the locking claw 35 of the roller guide 34 projects to the upper end of the tray stacking surface.

In this state, the sheet discharged from the copying apparatus main body 100 passes through the conveying path 6 and the roller pair 1
After being transferred to the rollers 7 and 18, the rollers 17 and 18 are ejected, but since the rotation guide 31 is rotated upward, the sheets are not ejected and are stacked on the staple tray 38. .

Here, the staple tray 38 is attached inside the main body 1 at an angle such that the sheets S are stacked on the staple tray 38 by its own weight. Also,
The tray 24 is positioned above the non-staple mode as shown in FIG. 13 so as to support the rear end of the sheet S and assist in returning to the upstream side in the discharge direction.

On the other hand, the sheet S discharged onto the staple tray 38 as shown in FIG.
And the sheet fall position of the tray 24 are set to be higher, which helps to drop the sheet toward the upstream side by its own weight by the discharge alignment belt 19 that rotates in the arrow direction in synchronization with the discharge roller 17. Staple tray 3
8 is urged in the upstream direction.

Therefore, the sheet S hits the contact plate 20 and is aligned in the direction perpendicular to the discharge direction. In addition, the alignment of the sheet S in the width direction is performed by the width aligning guide 21.
(See FIGS. 3 and 4), the sheet S falls onto the staple tray 38 and starts to operate at a predetermined time of hitting the abutting plate 20, and the sheet S is moved from the inner side of the body by a predetermined dimension larger than the width dimension of the sheet S. By moving to the front side, the sheet S is aligned in the front direction. Hereinafter, the above operation is repeated until the second and subsequent sheets S are all stacked on the staple tray 38 by the number set by the user.

Then, as shown in FIG. 14, when the number of sheets set by the user is aligned on the staple tray 38, the stapler operates and staples at the position set by the user. Note that when stapling is completed, FIG.
The rotation guide 31 descends as shown in FIG.
Is rotated in the direction of the arrow, the stapled sheet S on the tray 38 is ejected as shown in FIG.

During the stapling operation, the sheets are sequentially ejected from the copying apparatus 100. Therefore, the leading first sheet of the ejected sheets of the next job is retained in the main body 1.
An operation is performed in which the sheet is discharged while being superposed on the second sheet.

The operation will be described with reference to FIGS. 17 to 20. FIG. 17 shows a state in which the sheet S has started to enter the main body 1.

The first sheet S1 discharged from the copying apparatus 100 is sent to the buffer path 8 when the upstream end portions of the flappers 3 and 4 are located below. The sheet S1 sent to the buffer path 8 is sent in the direction indicated by the arrow in the figure while being wound around the buffer roller 9. Where flapper 3
18, the sheet S1 is rotated so that the sheet S1 is fed in the direction of the roller 15, and the sensor 11 detects the leading edge of the sheet S1.
Stop in the state as shown in.

Then, when the second sheet S2 enters as shown in the figure, the buffer roller 9 starts to rotate, and as shown in FIG. 19, the first and second sheets S2.
1 and S2 are stacked and transported. Furthermore, the first sheet S
When the rear end of the sheet 1 passes the position of the flapper 39, the flapper 39 rotates so that the sheet S is fed toward the discharge rollers 17 and 18 as shown in FIG. Is discharged to By performing the above operation, the sheet S is not discharged from the discharge rollers 17 and 18 while the stapler is performing the stapling operation, the stapling operation can be performed, and the operation of the copying apparatus 100 is stopped. Never do.

Further, in order to further increase the time for performing the stapling operation, it is possible to wind the third or more sheets S around the buffer roller 9.

By repeating the above operation, a plurality of staple copy bundles Sa are created, but as shown in FIG.
When there are already stapled copy bundles Sa on the tray 24, if the sheets S exceed the point G at the upper end of the already stacked copy bundles Sa when the deflection or bulge of the copy bundle Sa is large. When the next sheet comes out, it may be caught and jammed, or it may become a load when the width aligning guide 21 operates and align, and the alignment may deteriorate.

However, at this time, since the roller guide 34 is in the same plane as the lower saw guide 27a and the locking claw 35 of the roller guide 34 projects above the tray 24, the rear end surface of the sheet S is Since it can be pressed, it is possible to prevent jamming and the like.

[0083]

As described above, according to the present invention, when the sheet is discharged, the shield member is rotated to close the upper space of the discharge port by the shield portion provided on the shield member.
It is possible to prevent the sheet from entering from the upper space.
As a result, the tray can be raised with a simple structure without causing a locked state. Further, when closing the discharge port, the shielding part and the regulating member form the same surface, so that the tray can be raised without the sheet being caught.

[Brief description of drawings]

FIG. 1 is a sectional view of a sheet post-processing apparatus and a copying apparatus embodying the present invention.

FIG. 2 is a sectional view of the sheet post-processing device.

FIG. 3 is a plan view of a staple tray portion of the sheet post-processing device.

FIG. 4 is a side sectional view of the staple tray portion.

FIG. 5 is an enlarged side sectional view of an essential part of the sheet post-processing apparatus.

FIG. 6 is a diagram showing how the rotation guide of the sheet post-processing device rotates.

FIG. 7 is an enlarged side sectional view of an essential part of the sheet post-processing device.

FIG. 8 is a diagram showing a state in which the rotation guide blocks the discharge port.

FIG. 9 is a diagram showing a state where the roller guide of the sheet post-processing device is in the first position.

FIG. 10 is a diagram showing a state in which the roller guide is in a second position.

FIG. 11 is a diagram showing how sheets are discharged to a second tray of the sheet post-processing device.

FIG. 12 is a diagram showing a state in which output sheets from a personal computer are stacked on a second tray.

FIG. 13 is a diagram showing a state of the second tray at the time of staple sorting.

FIG. 14 is a diagram showing a state in which the number of sheets set by the user is aligned on the staple tray.

FIG. 15 is a diagram showing how stapled sheets are ejected.

FIG. 16 is a diagram showing how a stapled sheet has been ejected.

FIG. 17 is a diagram showing a state in which a sheet has started to enter the sheet post-processing apparatus.

FIG. 18 is a diagram showing a state in which the first sheet is wound around a buffer roller.

FIG. 19 is a diagram showing a state in which the first and second sheets S1 and S2 are stacked and conveyed.

FIG. 20 is a diagram showing a state in which two sheets are discharged in a stacked state.

FIG. 21 is a side sectional view of a main part of a conventional sheet post-processing device.

[Explanation of symbols]

 1 Sheet Post-Processing Device 23, 24, 25 Tray 27 Upper Regulation Member 31 Rotation Guide 31b Shutter Part 32 Ejection Roller 32A Roller Pair 33 Moving Ejection Roller 35 Cam 100 Copier S Sheet M Drive Source

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroaki Namiki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Minor Kawanishi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (3)

[Claims] 1. A main body for performing post-processing such as sheet binding, a discharge port formed on a side wall surface of the main body for discharging a sheet, and a sheet mounted in an inclined state on the wall surface and discharged from the discharge port. A sheet post-processing apparatus having a vertically movable tray for stacking sheets, and an upper regulation that forms an upper wall surface of the discharge port and abuts on an inclined end of the sheets stacked on the tray. A member, a roller pair that rotates in a state of sandwiching a sheet and discharges the sheet from the discharge port, holds one roller of the roller pair, and closes an upper space of the discharge port when discharging the sheet. A rotatable shield member having a shield portion for preventing sheets from entering from the upper space; and the shield member, wherein one roller is separated from the other roller during a binding operation. While the roller pair is rotated to the first position in which the sheet cannot be discharged, the one roller is pressed against the other roller at the time of discharging the sheet, and the shielding portion forms the same surface as the upper regulating member. A sheet post-processing apparatus comprising: a rotating unit that rotates to a second position that closes the upper space of the discharge port. 2. A discharging means for discharging a sheet, a first tray for supporting an upstream side portion of the sheet discharged by the discharging means in a discharging direction, and a sheet for which an upstream side portion is supported by the first tray. A second tray that can move up and down with respect to the first tray supporting a downstream side portion of the sheet, and a sheet stacked over the first tray and the second tray is moved to the second tray. A pair of moving means, and the second
Of the moving means and one of the moving means are rotatably supported, and the pair of moving means are separated from each other at the first position. A guide member configured to stack sheets on the tray and the second tray, and to press the pair of moving means under pressure at the second position to discharge the sheet to the second tray,
In the sheet post-processing apparatus having, in the state where the guide member is in the second position,
The sheet post-processing device, wherein the guide member closes the discharge port of the first tray and is on the same plane as the regulating means. 3. An image forming apparatus comprising an image forming section and a sheet post-processing apparatus for post-processing a sheet on which an image has been formed by the image forming section, wherein the sheet post-processing apparatus is claim 1 or An image forming apparatus, which is the sheet post-processing apparatus according to item 2.