JP2020045227A - Sheet ejection device - Google Patents

Abstract

To enable orderly stacking of sheets on a stacking tray by changing a discharge direction of the sheets ejected from an ejection port without using complicated equipment.SOLUTION: A conveyance guide 24b is formed at a base end of an upper stacking tray 24. A vertical position of the upper stacking tray 24 with respect to an ejection port 50 is adjusted. Sheets ejected from the ejection port 50 by a pair of ejection rollers 32 and 33 comes into contact with the conveyance guide 24b, with its ejection direction changed, and are stacked neatly on a lower stacking tray 25.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a sheet discharge device that discharges a sheet to a stack tray in an image forming apparatus, a sheet processing apparatus, and the like.

  Conventionally, a sheet processing apparatus has a plurality of stacking trays, and these stacking trays can be moved in a vertical direction by a tray unit, and a sheet or a sheet bundle from the sheet processing apparatus is selected for the plurality of stacking trays. (Patent Document 1).

  In addition, the stacking tray is moved up and down according to the number of discharged sheets, and a pair of discharge guides having a discharge roller at the leading end are vertically movable, so that the sheet discharge angle can be changed. A paper post-processing apparatus has been proposed (Patent Document 2).

JP-A-10-218476 JP 2010-126331 A

  In the sheet processing apparatus of Patent Document 1, the lower discharge roller is located at a fixed position disposed on the machine body, and the upper discharge roller is disposed on a rotation guide and can be moved up and down. When the sheet or sheet bundle is discharged onto the discharge tray, the upper and lower discharge rollers are at a fixed position. For this reason, when the sheet having a large coefficient of friction, the curled sheet, or the angle of the sheet stacking surface of the stacking tray is different, there is a problem that the stackability and alignment of the sheets on the stacking tray are reduced.

  The paper (sheet) post-processing device of Patent Document 2 can change the paper discharge angle and the interval between the pair of paper discharge rollers by controlling the pair of paper discharge guides up and down, respectively, and thereby the paper mode and the number of sheets. The sheet discharge angle can be adjusted to a condition suitable for the situation such as the characteristics of the sheet. However, a dedicated device for adjusting the rotation angle of the pair of paper ejection guides is required, and the power transmission to the ejection roller at the tip of the paper ejection guide complicates the configuration, resulting in high cost and failure. Malfunctions are likely to occur.

  In view of the above, the present invention provides a sheet discharge device that can adjust the discharge angle to the stacking tray without using a special device such as adjusting the discharge angle of the discharge roller pair, thereby solving the above-described problem. It is intended to provide.

  The present invention provides a sheet conveying path for conveying a sheet, a sheet discharging roller pair disposed near a discharge port of the sheet conveying path, and a plurality of stacking trays for stacking sheets discharged from the discharging port, A tray vertical moving means for vertically moving at least an upper stacking tray in the plurality of stacking trays, and a lower stacking device disposed at a base end of the upper stacking tray from the discharge port by the discharge roller pair. A sheet guide that comes into contact with the sheet discharged to the tray and changes the direction in which the sheet is discharged.

  According to the present invention, the sheet discharged from the discharge port is conveyed by controlling the vertical position of the upper stacking tray by a tray vertical moving means by a simple device for providing a conveying guide at the base end of the upper stacking tray. It is possible to change the discharge direction of the sheets discharged to the lower tray guided by the guide, and to improve the stackability and alignment of the sheets stacked on the lower tray.

1 is a longitudinal sectional front view showing an image forming apparatus provided with a sheet processing apparatus to which the present invention can be applied. FIG. 3 is a vertical sectional front view showing the sheet processing apparatus. FIG. 3 is a plan view showing a staple tray portion of the sheet processing apparatus. The front view. FIG. 3 is a front cross-sectional view illustrating a state in which a rotation guide of the sheet processing apparatus is closed. The perspective view which shows the said rotation guide. FIG. 3 is a front sectional view showing a state where a rotation guide of the sheet processing apparatus is opened. FIG. 3 is a front cross-sectional view illustrating a state in which a snowboard shutter of the sheet processing apparatus is closed. FIG. 3 is a front view showing a driving unit of the snowboard shutter. FIG. 3 is a front sectional view showing a sheet discharge unit of the sheet processing apparatus. FIG. 3 is a front cross-sectional view illustrating a different state of a sheet discharge unit of the sheet processing apparatus. FIGS. 7A and 7B show a base end portion of an upper discharge tray, and FIGS. 7A and 7B show different embodiments. FIGS. FIGS. 4A, 4B, and 4C show different states of sheet discharge. FIGS. FIG. 2 is a block diagram showing a control device. FIG. 6 is a flowchart showing a sheet discharging operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an internal configuration of a copying apparatus which is an image forming apparatus. A copying apparatus U includes a copying apparatus main body 100 and a sheet processing apparatus 1, and performs automatic document feeding to the copying apparatus main body 100. A cassette 200 capable of stacking a plurality of sheets (sheets) having different sizes from a document feeder (hereinafter, referred to as an ADF) 300 is provided.

  First, in the copying apparatus main body 100, 101 is a document table glass on which a document is loaded, 103 and 104 are scanning reflection mirrors (scanning mirrors) for changing the optical path of reflected light of the document, and 105 is a focusing and scaling function. , A first scanning mirror having an illumination lamp and a mirror for reading an original sent from the ADF 300, 107 a registration roller, 108 and 110 photosensitive drums and pressure rollers, 109 a developing device, 111 an image A transport belt 112 transports the recorded sheet to the fixing side. Reference numeral 112 denotes a fixing device that thermally compresses the transported sheet.

  113 and 117 are conveying rollers for conveying the sheet, 114 is a flapper for switching the conveying direction of the conveyed sheet, 115 is a conveying roller for conveying the sheet in the direction of the sheet processing apparatus 1, and 116 is the reverse of the sheet. Reference numeral 118 denotes a transport roller for transporting the paper from the paper feed cassette to the photosensitive drum unit, and 119, 120, and 121 denote rollers for transporting the paper from the manual feed unit, a manual tray, and a separation pad. Reference numerals 122, 123, and 125 denote laser and polygon mirrors for forming an image on the photosensitive drum, and mirrors for changing the optical path. Reference numeral 124 denotes a motor for driving the polygon mirror 123.

  Reference numeral 200 denotes a paper feed cassette which stacks sheets of each size by type and supplies the sheets to the main body by type according to a signal from the copying apparatus main body 100; 201, a conveying roller for pulling out the paper from the cassette; This is an intermediate roller that transfers the paper sheet upward.

  Meanwhile, the surface of the photosensitive drum 108 is made of a photoconductor and a seamless photosensitive member using a conductor. The drum 108 is rotatably supported by a shaft and a main motor (not shown) that operates in response to pressing of a copy start key. (Not shown), rotation is started in the direction of the arrow in FIG. 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 a light receiving element and sent to an image processing unit (not shown), while a predetermined data processing received by the main body from the user in the image processing unit is performed. After being performed, it is sent to the laser unit 122. The electric signal subjected to the data processing is converted into light by the laser unit 122, reflected by the polygon mirror 123 and the mirror 125, becomes an electrostatic latent image on the photosensitive drum 108, and is visualized by toner. The image is transferred onto a sheet as described later.

  The sheet set on the cassette 200 or the manual feed tray 120 is fed into the copying apparatus main body 100 by the feed rollers 118, 119, 201, and 202, and is moved toward the photosensitive drum 108 at an accurate timing by the registration roller 107. The leading edge of the latent image is aligned with the leading edge of the sheet. Thereafter, the sheet passes between the photosensitive drum 108 and the roller 110, so that the toner image on the drum 108 is transferred onto the sheet.

  After that, the sheet is separated from the drum 108, guided to the fixing device 112 by the conveyor belt 111, and transferred by pressing and heating. The sheet on which an image has been formed in this manner is advanced by the flapper 114 in the direction of the discharge roller 115, and is discharged to the sheet processing apparatus 1 with the print surface facing upward.

  On the other hand, in the ADF 300, reference numeral 301 denotes a stacking tray on which a bundle of originals 302 is set. Thus, the sheet is conveyed to the exposure position of the original table glass 101 via 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 conveying roller 307 via the path IV, and is returned to the upper surface of the original bundle 302 again by the discharge roller 308. Reference numeral 309 denotes a recycle lever for detecting one cycle of the original. The recycle lever is placed on the upper portion of the original bundle at the start of original feeding, and originals are sequentially fed. When the document falls, one cycle of the document is detected.

  On the other hand, in the case of a two-sided original, the original is once guided from paths I and II to III, and the rotatable switching flapper 310 is switched there to guide the leading end of the original to path IV. After being conveyed onto the platen glass 101 by the full-surface belt 306, it is 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 part of the sheet processing apparatus 1. When the sheet processing apparatus 1 is connected to the copying apparatus main body 100, the stopper member 2 is formed on a side surface of the copying apparatus main body 100 by the stopper member 2. Is positioned and attached to the holding unit 133. Further, a folding machine unit or a mounting table 70 is formed below the sheet processing apparatus 1, and a caster 80 is movably mounted on the table 70.

  Therefore, when performing a jam processing near the paper discharge unit of the copying apparatus main body 100 or a jam processing at the transfer unit between the sheet processing apparatus 1 and the copying apparatus main body 100, the stopper member 2 is moved in the X direction shown in FIG. By rotating to release the engagement with the hold portion 133, and then moving the sheet processing apparatus 1 in the horizontal direction to separate the copying apparatus main body 100, the copying can be easily performed.

  On the other hand, the sheet on which the image has been formed is conveyed to either the sheet processing apparatus 1 or a folding device (not shown) provided inside the mounting table 70 in accordance with the subsequent processing.

  That is, when the sheet is processed by the sheet processing apparatus 1, the upstream end of the first flapper 3 near the copying apparatus main body 100 shown in FIG. By locating the upstream end of the second flapper 4 in the upward direction, the sheet is sent to the first transport (path) path 6 through the roller pair 5 and further downstream from the first transport (path) path 6. Become like 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.

  In FIG. 2, reference numeral 8 denotes a second transport path (buffer path), 9 denotes a buffer roller, 14, 15, and 16 denote buffer rollers, 10, 11, 12, and 13 denote sheet detection sensors, and detect and detect a passing sheet. It performs detection of staying sheets and the like. Reference numeral 17 denotes a first discharge roller, reference numeral 18 denotes a press roller, and reference numeral 19 denotes a discharge alignment belt, which is sandwiched between the first discharge roller 17 and the press roller 18 and rotates. An endless rib (not shown) is provided in the vicinity, and is configured to rotate by engaging with the first discharge roller 17. The first discharge roller 17, the pressing roller 18, and the discharge alignment belt 19 form a discharge unit.

  Reference numeral 21 denotes a width adjusting plate for aligning the sheets at the time of sheet alignment. Reference numeral 20 denotes an abutment plate, which is configured to take a home position when sheets are sequentially stacked and a retract position when the stapler 22 moves back and forth. The contact plate 20 having the same phase as that of 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 in the width direction of the sheet is performed by the width adjusting guide 21 shown in FIGS. Further, the stapler 22 performs stapling by moving in a range indicated by an arrow in FIG. 3 so as to perform binding at two places, binding at one place at the front side, and binding at one place at the back side of the sheet. 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 24 and 25 denote first (upper stacking) trays for stacking sheets discharged from the discharge port 50 formed in the side wall surface 1a of the sheet processing apparatus 1 and second (lower stacking) trays. A) a tray unit (tray up / down moving means) attached to the side wall surface 1a; the tray unit 26 can move the first tray 24 in the vertical direction across the discharge port 50; The first tray 24 has a sheet stacking surface 24c on which sheets discharged from the discharge port 50 are stacked, and a sensor 24a for detecting the stacked sheets is provided on the sheet stacking surface. The sheet stacking surface 24c has a gentle downward slope toward the side wall surface 1a, and is inclined such that the base end is thicker and thinner toward the front end so as to withstand the weight of the sheet on the sheet stacking surface 24c. . A lower surface corner of the base end of the first tray 24 is cut out so that a sheet or the like is curved to have a curved surface, and the notch is used as a conveyance guide 24b for guiding a sheet from the discharge port 50. Is formed. The sheet discharge direction (sheet discharge angle) of the sheet to be discharged to the second tray 25 can be changed depending on the position of the transport guide 24b with respect to the discharge port 50 based on the vertical movement of the first tray 24 by the tray unit 26. A discharge device H is configured, and the sheet discharge device H will be described later.

  The second tray 25 is fixedly disposed below the discharge port 50, has a steep downward slope from the side wall surface 1a toward the outside (in the sheet discharging direction), and the sheet leading end stopper 39 rises upward at the leading end. It is formed as follows. Accordingly, the discharge direction of the sheet discharged from the discharge port 50 is adjusted by the conveyance guide 24b, and the leading end of the downwardly facing sheet bundle is received by the sheet leading end stopper 39, and the sheet stacking on the second tray 25 is performed. It is loaded on the surface 25c. Therefore, the angle of the sheet stacking surface 25c of the second (lower stacking) tray 25 is different from the angle of the sheet stacking surface 24c of the first (upper stacking) tray 24. Further, the second tray 25 can be changed to a tray having a different loading surface. The second tray 25 may be a simple tray such as a wire. The tray unit 26 is mounted on the side wall surface 1a of the sheet processing apparatus 1 so as to be movable in the vertical direction, and is moved in the vertical direction by a driving source (not shown) built in a lower part thereof. .

  In FIG. 5, reference numeral 31 denotes a rotation guide (shielding member) which rotatably holds the movable discharge roller 33, and at the time of discharging the sheet, the cam 35 shown in FIG. 5 to rotate downward about the rotation shaft 31a as a fulcrum, to move the movable discharge roller 33 to a first position where the movable discharge roller 33 is pressed against the discharge roller 32 so as to discharge the sheet as shown in FIG. Things.

  Further, in a staple mode described later, the rotation guide 31 is rotated upward to a second position for retracting the moving discharge roller 33 from the sheet carry-out path R as shown in FIG. From the sheet dischargeable state to the sheet discharge disabled state.

  Further, the rotation guide 31 is provided with a sliding surface (FIG. 5) 31b, which rotates downward during normal sheet discharge or tray movement. By blocking the notch 271 of a certain upper regulating member (hereinafter referred to as an upper sliding guide) 27, the backflow of the sheet is prevented.

  Note that a plurality of ribs 311 are formed in the vertical direction on the front surface of the sliding surface 31b which comes into contact with the sheet S as shown in FIG. The provision of the ribs 311 allows the sheet to be slippery and not to be caught when the first tray 24 on which the sheet is stacked moves up and down.

  5 and 8, below the discharge roller 32, there is a lower regulating member (hereinafter, referred to as a lower snowboard guide) 27a having the same surface as the sliding surface of each of the upper snowboard guide 27 and the rotation guide 31. A plurality of ribs are formed on the sliding surface, similarly to the rotation guide 31.

  However, a slope 27b is formed immediately below the discharge roller 32 of the lower snowboard guide 27a in order to improve sheet dischargeability, stackability, and alignment.

  The outer peripheral portion of the discharge roller 32 is slightly recessed from the sliding surfaces of the upper and lower sliding guides 27 and 27a and the rotation guide 31 so as not to hinder the movement of the tray 24 and the sheet S in the vertical direction. Placed in the position. A slanting shutter (discharge port opening / closing member) 30 which is inside the lower slanting guide 27a and a part of which forms a slope 30g, is slidably mounted in the up-down direction. The snowboard shutter 30 has a comb-shaped upper part, and the front side forms a slope 30g that is gentler than the slope 27b of the lower snowboard guide 27a, and is alternately arranged with the comb teeth on the slope 27b. By providing the slopes 30g and 27b on the snowboard shutter 30 and the lower snowboard guide 27a, respectively, it is possible to improve the stackability and alignment of the rear end of the sheets stacked on the first tray 24.

  As shown in FIG. 9, the lower end of the saw blade 30 has a groove 30e between the projections 30c and 30d, into which the rotating end 34b of the small link 34 is fitted. Note that 34a in FIG. 9 is a fixed end of the small link 34. The lower end 35a of the large link 35 is fitted to the rotating end 34b of the small link 34, and the upper end 35b is fitted to the pin 36a near the outer ring of the cam 36 which forms a part of the main body drive system. I have. The pin 36a has a top dead center A and a bottom dead center B set at the rotation position of the cam 36, and recesses 36b, 36b are formed so as to be able to stop and hold at the respective positions. Each click spring 37 is engaged. Therefore, when the cam 36 rotates, the upper end of the large link 35 rotates, but the lower end is regulated by the small link 34, so that the upper link 35 swings up and down around the fixed end 34a. Therefore, the snowboard shutter 30 can be interlocked in the vertical direction.

  By the way, when the snowboard shutter 30 simply moves up and down, the slope 30g is formed on the upper surface of the snowboard shutter 30. Therefore, even when the discharge port 50 is closed, the upper end of the snowboard shutter and the upper snowboard guide 27 do not move. A step is generated between the sliding surface and the sliding surface. In this case, when the sheet passes through the discharge port 50, the sheet falls down or gets stuck at the stepped portion, disturbing the alignment of the sheet, or the sheet lifts the rotation guide 31 and causes the malfunction. It may cause trouble. Therefore, projections 30a and 30b are formed on the back side of the comb teeth portion above the saw blade shutter 30. On the other hand, a protrusion 30c is provided on the rotation guide 31 at a position overlapping with the protrusion 30a when the slender shutter 30 closes the discharge port, in accordance with the protrusion 30a of the saw blade shutter 30. Further, the protrusion 30b of the saw blade shutter 30 is provided at a position overlapping with the end 38a of the staple tray (internal tray) 38 when the shutter blade 30 closes the discharge port 50. Furthermore, the height of each of the projections 30a, 30b, 30c is such that the inclined surface 30g is flush with the sliding surface of the upper and lower snowboard guides 27, 27a when the snowboard shutter 30 covers the discharge port 50. Is set. Further, a spring for urging (urging means) 30f is mounted on the snowboard shutter 30, and always urges the snowboard shutter 30 toward the main body.

  FIG. 8 shows a state in which the saw blade shutter 30 is closed in such a configuration. The protrusion 30a of the snowboard shutter 30 stops at a position overlapping with the protrusion 31c, the protrusion 30b stops at a position overlapping with the end 38a of the staple tray 38, and the slope 30g connects the vertical sliding surface of the upper snowboard guide 27 and the lower snowboard guide 27a. The outlet is blocked by the shape. By configuring the sheet processing apparatus in this manner, the rotation guide 31 is lowered when the tray is moved, and the sliding shutter 30 is moved to a position that closes the discharge port 50. The slope 30g of the snowboard shutter 30 can be made the same as the sliding surface of the upper snowboard guide 27 and the lower snowboard guide 27a, and when the tray 24 passes through the discharge port 50, the sheets S stacked on the tray Not only does not flow back to the discharge port 50, but also can smoothly pass through the discharge port 50, so that the stacking / alignment is not disturbed.

  Next, the operation of the sheet processing apparatus thus configured will be described.

  In the present embodiment, for example, normal sheets are stacked on the first tray 24, and long sheets are stacked on the second tray 25. FIG. 10 shows a case where a normal sheet is discharged to the first tray 24 in the non-staple mode.

  When the non-staple mode is selected by the user, the cam 35 (see FIG. 6) causes the rotation guide 31 to press the movable discharge roller 33 against the discharge roller 32 as shown in FIG. Is rotated to a position where the notch 271 is closed. In this state, the sheet discharged from the copying apparatus main body 100 is passed to a pair of rollers 17 and 18 through a transport path 6 shown in FIG. 2 and is further discharged downstream by the pair of rollers 17 and 18 and then rotated. The sheet is directed toward the tray 24 by the moving guide 31, is discharged from the discharge port 50 via the discharge roller pairs 32 and 33, and is sequentially stacked on the tray 24. When a large number of normal sheets S are taken, first, it is confirmed by the paper presence sensor 24a (see FIG. 2) installed in the first tray 24 that no sheet remains on the tray 24, and then the tray unit 26 Moves to a predetermined position for receiving the first sheet on the first tray 24.

  Further, when the number of stacked sheets reaches a certain number, the tray unit 26 is lowered to a position determined so that 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 number of sheets has been loaded in the tray, a stop signal is output to the copying apparatus main body 100 to temporarily stop the sheet discharge.

  Next, discharge of sheets to the second tray 25, which is a main part of the present invention, will be described with reference to FIG. Generally, a long sheet is discharged to the second tray 25 by the discharge device H described above. The image-formed sheet introduced into the sheet processing apparatus 1 passes through a sheet conveying (path) path 6 by the conveying roller 5, and further from the discharge port 50 by the discharge roller pairs 32 and 33 via the discharge roller pairs 17 and 18. Is discharged. At this time, as shown in FIG. 11, the first (upper stacking) tray 24 is moved by the tray unit 26 so as to be located above the discharge port 50, and is located at the base end of the first tray 24. The formed transport guide 24b is positioned so as to face the discharge port 50. As a result, the long sheet discharged from the discharge port 50 is changed so that the leading end thereof contacts the transport guide 24b and faces downward along the guide surface. The sheet is discharged toward the lower tray 25 and is sequentially stacked on the downward second tray 25 with the leading end received by the sheet leading end stopper 39.

  When the number of sheets stacked on the second tray 25 reaches a predetermined value and the stacked thickness of the sheets on the second tray 25 reaches a predetermined amount, the first tray 24 is raised by a predetermined amount. Is also good. As a result, the leading end of the sheet discharged from the discharge port 50 by the pair of discharge rollers 32 and 33 abuts on the lower side of the conveyance guide 24b, that is, the position away from the discharge port 50, and the downward angle of the sheet slightly increases. Therefore, the sheets are stacked on the second tray 25 without interference with the already stacked sheets stacked on the second tray 25.

  As described above, the sheet discharge device H is provided with the transport guide 24b at the base end of the first tray 24, which is the upper stacking tray, and makes the sheet from the discharge port 50 abut on the transport guide 24b to remove the sheet. Although the discharge angle is controlled, the adjustment of the sheet discharge angle based on the sheet stacking amount is not limited to the above-described predetermined value of the number of sheets, and the first tray may be raised little by little according to the discharge of the sheet. Further, the first tray may be fixed at a fixed position regardless of the sheet stacking amount.

  In the above-described embodiment, as shown in FIG. 12A, the transport guide 24b having a single curved guide surface such as an arc is provided at the base end of the first (upper stacking) tray 24. As shown in (b), for example, a transport guide 24b including a plurality of guide surfaces 24b1, 24b2, and 24b3 having different angles such as a plurality of arcs having different centers may be provided. As shown in FIG. 13A, when the sheet is initially discharged by the discharge roller pairs 32 and 33, that is, when the number of sheets discharged (stacked) to the second tray 25 is equal to or smaller than a predetermined number (first number), the first sheet is discharged. The tray 24 is located at a relatively upper position, and the first guide surface 24b1 of the transport guide 24b faces the discharge port 50. As a result, the end of the discharged sheet S from the discharge port 50 abuts on the first guide surface 24b1 having a large downward angle (the center of the arc is upward and on the sheet processing apparatus side), and the arc of the first guide surface 24b1 is formed. The ink is discharged downward toward the second tray 25 at a relatively tight angle.

  When the number of discharged sheets exceeds the first number, the first tray 24 is raised by a predetermined amount as shown in FIG. In this state, the discharge port 50 faces the second guide surface 24b2 of the transport guide 24b, and the sheet discharged by the discharge roller pair 32, 33 has the second guide surface 24b2 at the lower middle angle (the center of the arc is the middle). , Is changed downward at an intermediate angle, and is stacked on the already stacked sheets S on the second tray 25.

  When the number of discharged sheets exceeds the second number, which is larger than the first number by a predetermined amount, the first tray 24 is further raised by a predetermined amount as shown in FIG. In this state, the discharge port 50 is opposed to the third guide surface 24b3 of the transport guide 24b, and the sheet discharged by the discharge roller pair 32, 33 has a gentle downward angle (the center of the arc is downward and the sheet processing device does not). The distant side) is guided by the third guide surface 24b3, is changed downward at a gentle angle, and is stacked on the already stacked sheets S on the second tray 25. As a result, the sheets sequentially discharged from the discharge port 50 are adjusted in a direction away from the sheet processing apparatus for each predetermined number of sheets, and even if there are a large number of discharged sheets, the second tray 25 is not interfered with the already stacked sheets. Loaded neatly on top.

  The selection of the plurality of guide surfaces 24b1, 24b2, and 24b3 is set according to the number of sheets stacked on the second tray 25, but the present invention is not limited to this. You may set according to a state etc. For example, the operation panel of the image forming apparatus (copying apparatus) U is configured to allow the user to input the basis weight of the sheet and select the type of the sheet, thereby setting the height of the first tray 24. Is also good. Further, the second tray 25 may be configured to be changeable to one having a different sheet stacking surface 25c, and the height of the first tray 24 may be set in accordance with the change. The setting of the height of the first tray 24 includes a case where the sheet from the discharge port 50 is set upward so as not to hit the conveyance guide 24b, and the discharge direction of the sheet by the conveyance guide is not changed.

  When the discharge rollers 32, 33 discharge the sheet toward the second (lower stacking) tray 25 and convey it for a predetermined distance, the sheet contacts the first (upper stacking) tray 24 with the conveyance guide 24b. It may be raised to a position where it does not occur, so as to prevent interference with the already loaded sheets.

  The number of transport surfaces of the transport guide is not limited to three, but may be two or four or more. Further, the shape of the transport guides 24b, 24b1, 24b2, 24b3 is preferably a circular arc, but is not limited to a circular arc, and may be another curved shape or an inclined shape. In the above-described embodiment, the non-staple mode sheets are stacked on the second tray 25. However, the present invention is not limited to this, and is applied to the case where a stapled sheet bundle is stacked on the second tray. May be. Further, the present sheet discharging apparatus is not limited to the sheet processing apparatus 1, and may be applied to the sheet discharging apparatus of the image forming apparatus main body 100, that is, the image forming apparatus (copying apparatus) having no sheet processing apparatus. Further, the above-described embodiment has been described with reference to the stacking trays in the upper and lower stages of the first tray 24 and the second tray 25; , The intermediate stacking tray becomes a lower stacking tray with respect to the upper stacking tray, and becomes an upper stacking tray with respect to the lower stacking tray, and the intermediate stacking tray also has a transfer guide similar to the upper stacking tray. Can be formed.

  FIG. 14 is a control block diagram of the sheet processing apparatus 1 including the first tray 24 and the second tray 25. In FIG. 14, for example, an input side of the CPU 200 as control means of the present embodiment includes: The sheet detection sensors 10, 12, and 13 for detecting sheets, the tray position detection sensor 204 for detecting the vertical position of the first tray, the operation panel 205 for transmitting sheet size data specified by the user to the CPU 200, and the like are electrically connected. Connected to On the other hand, a transport motor 206, a tray motor 207 for moving the first tray up and down, and the like are electrically connected to the output side of the CPU 200 via drivers D1 and D2, respectively. Further, the CPU 200 has, for example, a ROM 201 and a RAM 202, which are memories, as storage units. The ROM 201 stores a post-processing control procedure executed by the CPU 200 and the like. The RAM 202 is a part for temporarily storing the sheet size and the like input by the user. The CPU 200 receives the signals from the above-described sensors and the ROM 201 and the RAM 202 and controls the motors and the like based on the signals so that post-processing control and the like can be executed. Further, the CPU 200 exchanges signals with the control unit of the image forming apparatus main body 100 to control the entire sheet processing apparatus 1.

  Next, an example of a method for controlling the stacking of sheets on the first tray 24 and the second tray 25 will be described based on a flowchart shown in FIG.

  When receiving the print request, the CPU 200 determines the discharge destination of the sheet (St101 to St102), and in the case of the first tray (the upper tray of St103), determines the height of the first tray as the sheet discharge position (St104). One tray is moved to the sheet discharge position below the discharge port (St105).

  If the sheet is to be discharged to the second tray (the lower tray of St103), the height of the first tray is determined to be the paper guide position (St106), and the first tray is moved to the guide position above the discharge port (St107). When determining the paper guide position, the position may be determined according to the sheet stiffness, the stacking amount of the second tray, the stacking angle of the second tray, and the like. After the movement of the first tray to the sheet discharge position or the sheet guide position is completed, the sheets are discharged from the discharge port 50 (St108), whereby the sheets are stacked on the first tray 24 or the second tray 25.

  As described above, according to the sheet processing apparatus of the embodiment, it is possible to discharge a sheet at an optimal discharge angle to a stacking tray having a different angle between the first tray and the second tray, and to improve sheet stacking performance. Further, there is an effect that it is possible to provide a sheet processing apparatus and an image forming apparatus that can be produced at low cost without lowering the alignment property.

Reference Signs List 1 sheet processing apparatus 6 sheet transport path 24 upper (first) loading tray 24b transport guides 24b1, 24b2, 24b3, guide surface 24c loading surface 25 lower (second) loading tray 25c loading surface 50 discharge port H sheet discharging device

Claims (7)

A sheet conveying path for conveying the sheet,
A sheet discharge roller pair disposed near a discharge port of the sheet conveying path,
A plurality of stacking trays for stacking sheets discharged from the discharge port,
Tray vertical moving means for vertically moving at least the upper stacking tray in the plurality of stacking trays,
A conveyance guide disposed at a base end portion of the upper stacking tray and abutting a sheet discharged from the discharge port to the lower stacking tray by the discharge roller pair to change a discharge direction of the sheet. Was
A sheet discharging device characterized by the above-mentioned. The lower stacking tray is different from the upper stacking tray in an angle of a stacking surface on which sheets are stacked.
The sheet discharging device according to claim 1. The lower stacking tray has a stacking surface suitable for stacking long sheets,
The sheet discharging device according to claim 2. A discharge angle of the sheet by the transport guide is controlled by a position of the upper stacking tray with respect to the discharge port by the tray vertical moving unit,
The sheet discharging device according to claim 1. The transport guide has a plurality of guide surfaces having different sheet discharge angles,
The sheet discharging device according to claim 4. The position of the upper stacking tray is set by the number of stacked lower stacking trays,
The sheet discharging device according to claim 4. The position of the upper stacking tray is set by the angle of the stacking surface of the lower stacking tray,
The sheet discharging device according to claim 4.

Images