JP3902962B2 - Sheet processing apparatus and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet processing apparatus that processes a sheet, and an image forming apparatus including the sheet processing apparatus, and more particularly to a sheet alignment operation that is performed when a sheet is processed.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine, a printer, or a facsimile, for example, a sheet after image formation is performed in order to reduce the labor required for processing such as alignment and binding to a sheet of copy paper after image formation. There are some which include a sheet processing apparatus that sequentially takes the sheet into the apparatus and performs processing such as alignment and binding on the sheet.
[0003]
In the sheet processing apparatus, when aligning sheets, a two-part configuration of a first intermediate stacking unit that performs alignment in the sheet conveyance direction and a second intermediate stacking unit that performs alignment in the sheet width direction is used. There is something that realizes. The second intermediate stacking unit provided downstream of the first intermediate stacking unit has a substantially U-shaped cross section in the width direction perpendicular to the sheet conveying direction. The sheet discharged on the first intermediate stacking unit is supported, and the central portion in the width direction of the sheet is not guided. Further, the second intermediate stacking unit is formed in a trumpet shape on the sheet carry-in side so that the carried-in sheet does not jam.
[0004]
In addition, a full load detection flag for detecting the full load of the sheets stacked on the sheet stack portion located below the second intermediate stack portion in the gravity direction is provided, and the full load detection flag is the first intermediate stack portion. And a second fulcrum having a rotation fulcrum above the pair of discharge rollers that can be brought into contact with and separated from each other.
[0005]
[Problems to be solved by the invention]
When the sheet is carried into the second intermediate stacking portion, the full load detection flag is turned and retracted. In order to prevent the full load detection flag from interfering with the second intermediate stack portion, It is difficult to form an appropriate guide shape by cutting the trumpet shape of the second intermediate stacking portion or changing the curvature of the trumpet shape.
[0006]
Further, if the wrapper shape of the second intermediate stacking unit is not appropriate, the discharge roller pair between the intermediate stacking units is separated when the sheet is carried into the second intermediate stacking unit, and the sheet is Since the distance from the last roller carrying the nip to the second intermediate stacking portion is long, the sheet is likely to curl upward, and the sheet tends to jam into an unsuitable trumpet shape and jam.
[0007]
In addition, the gap amount of the conveyance path formed by the U-shape of the second intermediate stacking portion is wide so that sheets can be allowed up to the maximum number of sheets that can be stapled. If this is done, the sheet with severe curl at the end in the width direction may be bent during alignment in the width direction, causing the force to escape, and the sheet side end cannot be pushed in reliably, resulting in poor alignment performance. It was.
[0008]
An object of the present invention is to reduce jamming of a sheet at a sheet carry-in portion to the second intermediate stacking unit.
[0009]
Another object of the present invention is to improve the alignment by ensuring that the sheet side end is pushed in during alignment in the sheet width direction.
[0010]
[Means for Solving the Problems]
To achieve the above object, a typical configuration of the present invention is a sheet processing apparatus that performs processing on a sheet discharged from the image forming apparatus main body, and aligns the end of the sheet in the conveyance direction against the wall. A first intermediate stacking unit; a discharging unit that discharges the sheet from the first intermediate stacking unit; and a sheet feeding and supporting sheet on the downstream side in the transport direction of the discharging unit, and a width direction end orthogonal to the transport direction of the sheet A second intermediate stacking unit having a function of aligning the sections, a sheet stacking unit below the second intermediate stacking unit in the direction of gravity, and a fullness detection flag for detecting the fullness of sheets in the sheet stacking unit The full load detection flag has a rotation fulcrum above the sheet discharge port by the discharge means, and can be rotated by the drive means around the rotation fulcrum, and the second intermediate Transporting sheets to the stacking section Sometimes, wherein the pivoted position functions as upper guide of the lower surface of the full load detecting flag is to guide the upper surface of the sheet to be carried into the second intermediate stacking portion.
[0011]
According to the above configuration, even when the sheet is curled to the upper surface side when the sheet is carried into the second intermediate stacking unit, the sheet is guided by the full load detection flag. Can reduce sheet jam at the carry-in part.
[0012]
In addition, when the sheets are carried into the second intermediate stacking unit, the full load detection flag sequentially changes the rotation angle in accordance with the number of sheets carried on the second intermediate stacking unit, By changing the gap amount of the sheet carry-in portion to the intermediate stacking portion, it is possible to further reduce the sheet jam at the carry-in portion to the second intermediate stacking portion.
[0013]
Further, when aligning the width direction end of the sheet by the second intermediate stacking unit, the upper surface of the sheet is sequentially urged by the full load detection flag so that the second intermediate stacking unit is aligned in the sheet width direction. Since the end is pushed in securely, the consistency is improved.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. As long as there is no specific description, it is not the meaning which limits the scope of the present invention only to them.
[0015]
[First Embodiment]
FIG. 1 is a schematic cross-sectional view showing an overall configuration of a laser beam printer which is an example of an image forming apparatus including a sheet processing apparatus according to a first embodiment of the present invention.
[0016]
(Overall configuration of image forming apparatus)
In FIG. 1, reference numeral 100A denotes a laser beam printer as an image forming apparatus, and reference numeral 100 denotes a laser beam printer main body (hereinafter referred to as a printer main body) as an image forming apparatus main body. The laser beam printer 100A is independently a computer or a LAN. The image is formed (printed) on a sheet by a predetermined image forming process on the basis of image information, a print signal, and the like sent from these computers and networks, and discharged.
[0017]
Reference numeral 300 denotes a sheet processing apparatus. The sheet processing apparatus 300 is arranged above the printer main body 100, and passes a sheet discharged from the printer main body 100 to the outside of the apparatus via a conveyance unit in the sheet processing apparatus. In the face-down state with the image side down, the first intermediate stacking unit 300B is loaded into and mounted on the second intermediate stacking unit 300C (slide guides 301 and 302 described later), and then the second intermediate stacking described later. Alignment is performed using the alignment function of the unit 300C, the sheets are bundled for each predetermined job, one or more of the sheets are stapled and discharged and stacked on the sheet stacking unit 325, or the sheet stacking unit is simply face down 325 is discharged and loaded.
[0018]
Here, the sheet processing apparatus 300 and the printer main body 100 are electrically connected by a cable connector (not shown). In addition, the sheet processing apparatus 300 includes a casing part 300 </ b> A that stores each part, and is detachable from the printer main body 100.
[0019]
(Printer configuration)
Next, the configuration of each unit of the printer main body 100 will be described along the conveyance path of the conveyed sheet S.
[0020]
In the printer main body 100, a plurality of sheets S are stacked in the feeding cassette 200, and the uppermost sheet S1 is sequentially separated and fed one by one by various rollers. The sheet S fed from the feeding cassette 200 by a predetermined print signal supplied from a computer or a network is first placed on the upper surface of the image forming unit 101 that forms a toner image by a so-called laser beam type image forming process. The toner image is transferred, and subsequently, heat and pressure are applied by the fixing device 120 on the downstream side, whereby the toner image is permanently fixed.
[0021]
Next, the sheet S on which the image has been fixed is folded back in a substantially U-shaped sheet conveyance path up to the discharge roller 130, so that the image surface is reversed, and the image surface is thus on the lower side. Then, the printer body 100 is discharged face down to the outside.
[0022]
Here, the sheet S is face-down provided on the upper portion of the printer main body 100 by, for example, a discharge roller 130 according to the position of the flapper 150 of the printer main body 100 that rotates based on a control signal from a control unit (not shown). (FD) Whether to be discharged to the discharge unit 125 or to the sheet stacking unit 325 of the sheet processing apparatus 300 is selected.
[0023]
(Configuration of sheet processing apparatus)
Next, the configuration of the sheet processing apparatus 300 and the movement of each part when the sheet S conveyed from the printer main body 100 goes to the sheet processing apparatus 300 will be described with reference to FIGS. 2 and 3.
[0024]
In FIG. 2, 330a is an upper discharge roller, 330b is a lower discharge roller, M is a jogger motor as a drive source, 322 is a paddle, 323 is a reference wall for abutting the rear end of the sheet (end in the conveyance direction). Here, as shown in the figure, the discharge roller pair 330 as discharge means composed of the discharge upper roller 330a and the discharge lower roller 330b is disposed on the downstream side in the sheet conveyance direction of the flapper 150 described above and is not used. It is rotationally driven by the illustrated drive motor.
[0025]
Further, the discharge upper roller 330 a is pivotally supported by an arm 330 c that can rotate around a paddle shaft 350. The jogger motor M (see FIG. 1) is a motor for driving slide guides 301 and 302 described later, and a stepping motor is used in this embodiment.
[0026]
Further, the paddle 322 serving as an alignment means at the end portion in the sheet conveyance direction is made of a flexible material such as rubber, and a plurality of paddles 322 are fixed to the paddle shaft 350 in a direction perpendicular to the sheet conveyance direction. When the sheet is discharged from the printer main body 100, the paddle shaft 350 is driven to rotate in the clockwise direction, whereby the sheet S moves in the direction opposite to the sheet conveying direction, and the rear end ( The end portion in the transport direction abuts on the reference wall 323 and is aligned. By providing the paddle 322 in this way, the consistency can be further improved.
[0027]
As shown in FIG. 3, in the sheet processing apparatus 300 of this embodiment, the second intermediate stacking unit 300 </ b> C (alignment unit) having a function of performing alignment in the width direction orthogonal to the sheet conveyance direction is detailed. A slide guide 301 and a slide guide 302, which will be described later, are provided. In the figure, H is a stapler that is a binding unit that staples the sheet bundle and performs a binding process on the sheet bundle. In this embodiment, the stapler H is an image surface of an image-formed sheet. In order to staple the upper left corner portion and bind each sheet, it is fixedly arranged on the slide guide 301 side.
[0028]
The sheet processing apparatus 300 configured as described above is configured to perform stapling processing based on a command output in advance from a computer or the like. Before S is discharged by the conveying roller 121 (see FIG. 1) provided in the printer main body 100, the flapper 150 is rotated counterclockwise by a solenoid (not shown) as shown in FIG. The conveyance path is switched to the sheet processing apparatus side.
[0029]
As a result, the sheet S is carried into the sheet processing apparatus 300 by the conveying roller 121. The sheet S thus carried into the sheet processing apparatus 300 is detected by rotating the flag 391 of the entrance sensor 390 in the clockwise direction, thereby causing the flag 391 to transmit the photosensor 392. Thereafter, the sheet S is conveyed upward by the entrance roller pair 363.
[0030]
(Discharge loading operation)
By the way, in the present embodiment, the sheet processing apparatus 300 is capable of stapling and discharging and stacking the sheet on the sheet stacking unit 325 and discharging and stacking on the sheet stacking unit 325 simply face down. Hereinafter, each discharge stacking operation will be described.
[0031]
(Face-down discharge loading)
First, an operation for discharging and stacking sheets on the sheet stacking unit 325 in a face-down manner will be described.
[0032]
In this case, as shown in FIG. 4A, the bottom surfaces of the slide guide 301 on the right side and the slide guide 302 on the left side with respect to the sheet carry-in direction are not in contact with the sheet S that is carried in, that is, the sheet S. Is retracted to a position outside by a predetermined amount from the width direction.
[0033]
Therefore, after the sheet conveyed by the inlet roller pair 363 passes through the staple roller pair 320, the sheet passes through the gap of the stapler H and then is conveyed by the discharge roller pair 330, and the arrow in FIG. 4B and FIG. As shown in (), the sheet falls toward the sheet stacking unit 325. At this time, the full load detection flag 600 of FIG. 2A is pushed up by the sheet S around the rotation center 601 and rotates as shown in FIG.
[0034]
(Discharge loading after stapling)
Next, an operation of stapling sheets and discharging and stacking them on the sheet stacking unit 325 will be described.
[0035]
Here, as shown in FIG. 4A, the bottom surfaces of the slide guide 301 on the right side and the slide guide 302 on the left side with respect to the sheet loading direction do not come into contact with the sheet S being loaded, that is, the width of the sheet S. As shown in FIG. 3A, the reference pins 303 and 304 provided on the wall surfaces of the slide guides 301 and 302 are prevented from interfering with the loaded sheet S from a position outside the direction by a predetermined amount. The sheet S is moved to a position outside a predetermined amount from the width direction of the sheet S. Before this movement, as shown in FIG. 9, the full load detection flag 600 rotates the arm 330c used as a drive means for the full load detection flag upward, and the cam surface 330d of the arm 330c causes the cam of the flag 600 to When the surface 600b is pushed up, it is retracted to the position shown in FIG. In this state, the slide guides 301 and 302 are moved to the state shown in FIG. 4A, the full load detection flag 600 is inserted into the slide guides 301 and 302, and the arm 330c is lowered again to a position where the discharge roller pair 330 nips. Prepare for sheet loading. This is an initial operation at the time of staple stacking.
[0036]
At this time, the distance between the end surfaces of the bottom surfaces of the two slide guides 301 and 302 is smaller than the width of the sheet S, and the two slide guides 301 and 302 are in such a position (first position). The second intermediate stacking unit 300C that supports the sheet S entering can be configured.
[0037]
Accordingly, the sheet conveyed by the inlet roller pair 363 passes through the staple roller pair 320 and then passes through the gap between the staplers H and is then conveyed by the discharge roller pair 330 to be the second configured by the slide guides 301 and 302. Are conveyed onto the guide surface of the intermediate stacking unit 300C.
[0038]
In the present embodiment, the arm 330c is used as the driving means for the full load detection sensor. However, the present invention is not limited to this. For example, a dedicated driving means may be provided separately.
[0039]
Here, as shown in FIG. 5A, the guide surface of the second intermediate stacking unit 300C is inclined at a predetermined angle with respect to the horizontal direction, and is mutually on the upstream side and the downstream side in the sheet carry-in direction. Specifically, a bent portion 300D that bends at an inclination angle α is formed between a predetermined section on the upstream side and a predetermined section on the downstream side. In addition, by having such a bent portion 300D, bending of the central portion of the sheet S that is not guided by the slide guides 301 and 302 forming the second intermediate stacking portion 300C is prevented.
[0040]
On the other hand, immediately after the first sheet is thus conveyed on the surface formed by the slide guides 301 and 302, the arm 330c rotates counterclockwise as shown in FIG. As a result, the discharge upper roller 330a pivotally supported by the arm 330c is retracted upward, and the discharge roller pair 330 is separated.
[0041]
(Guide function for full load detection flag)
At this time, as shown in FIG. 9, the full load detection flag 600 is lifted in the slide guides 301 and 302 by the cam surface 330 d of the arm 330 c around the rotation center 601. Here, as shown in FIG. 9, the guide upper surface 700 of the slide guides 301 and 302 and the flag lower surface 701 of the full load detection flag 600 pass through the discharge roller pair 330 spaced from the first intermediate stacking portion 300 </ b> B, and then the second. A trumpet shape is formed to facilitate carrying of the sheet into the intermediate stacking unit 300C. As a result, as shown in FIG. 10, when the sheet S is carried into the slide guides 301 and 302 (second intermediate stacking portion 300C) in an upper curl (curled to the upper surface side), the slide guide 301 and It serves to guide the sheet S into 302. When the full load detection flag 600 is pushed with a predetermined force or more due to the sheet S being abutted, the full load detection flag 600 is rotated upward, so that the roundness of the sheet is reduced.
[0042]
At the same time, the drive connected to the discharge roller pair 330 is cut off, and the rotation of the discharge upper roller 330a and the discharge lower roller 330b is stopped. As a result, when the trailing edge of the sheet S completely passes through the staple roller pair 320 from the gap in the state where the discharge roller pair 330 is separated, the sheet S returns to the direction opposite to the conveyance direction by its own weight and moves toward the reference wall 323. To do.
[0043]
(Alignment operation in the sheet width direction)
Next, only the left slide guide 302 operates, and the alignment operation in the width direction of the sheets S stacked on the first intermediate stacking unit 300B and the second intermediate stacking unit 300C is started. Specifically, when the slide guide 302 is driven by the motor M and moves to the right side in FIG. 3, the reference pin 304 provided on the slide guide 302 contacts the left side surface of the sheet S and moves toward the slide guide 301 side. The sheet S is pushed in.
[0044]
Then, when the right side surface of the sheet S abuts on a reference pin 303 provided on the slide guide 301, the slide guide 302 moves to the position shown in FIG. 6, and alignment in the width direction of the sheet is performed. It is set so that the sheet S moves to a set staple position at a position where the sheet S is in contact with the reference pin 303 and aligned. After the alignment operation, the slide guide 302 moves in a direction wider than the width of the sheet S so that the next sheet can be conveyed again at the standby position.
[0045]
(Configuration of slide guide)
Here, the configuration of the slide guides 301 and 302 will be described in detail.
[0046]
As shown in FIG. 3, each of the slide guides 301 and 302 is guided by a total of four guide pins 313a provided on the mold frame F and guide pins 313b provided on the sheet metal frame F ′. It can be reciprocated in the left-right direction, that is, the direction (width direction) perpendicular to the sheet conveying direction, and moved by the driving force from the jogger motor M.
[0047]
Further, when viewed from the downstream side in the sheet conveyance direction, the slide guides 301 and 302 are each a wall portion that guides both sides of the sheet S and a support portion that supports the upper and lower surfaces of the sheet S, as shown in FIG. And has a substantially U-shaped cross section, and the lower surface of the U-shape supports each sheet discharged onto the first intermediate stacking unit 300B and carried into the second intermediate stacking unit 300C. In addition, the central portion of the sheet S in the width direction is not guided.
[0048]
Further, the slide guide 302 is provided with a slide rack portion 310 having a flat gear that meshes with the step gear 317. A slide rack 312 having a flat gear that meshes with the step gear 317 is also attached to the slide guide 301.
[0049]
Here, the slide rack 312 is provided to be movable relative to the slide guide 301 via a coiled spring 314. The spring 314 has one end abutting on the slide guide 302 and the other end abutting on the slide rack 312 and urges the slide guide 301 and the slide rack 312 to expand. The slide rack 312 has a square hole 312a for moving the embossed portion 301a on the slide guide 301 side.
[0050]
Further, two reference pins 303 made of metal having excellent wear resistance are provided on the side wall of the slide guide 301, and two reference pins 304 are provided on the side wall of the slide guide 302, respectively. When doing so, the slide guide 302 moves as described above, and the reference pin 304 and the pin 303 come into contact with the both side end faces 305 and 306 of the sheet.
[0051]
The slide guide 301 and the slide guide 302 are supported in the height direction by a step gear 317 and a jog sheet metal frame F ′.
[0052]
(Slide guide operation)
Next, the operation of each slide guide 301, 302 will be described.
[0053]
When the sheet processing apparatus 300 is turned on, the staple roller pair 320 starts to rotate, and then the jogger motor M rotates and the step gear 317 rotates, so that the rack portion 310 of the slide guide 302 is driven to the outside. Evacuate to.
[0054]
Further, when the jogger motor M rotates and the step gear 317 rotates, the slide guide 301 first moves the slide rack 312 relatively, and the square hole portion 312a of the slide rack 312 moves to the right side of the embossed portion 301a of the slide guide 301 in FIG. After coming into contact with the end face, it is retracted to the outside by being pressed by the square hole 312a.
[0055]
The slide guide 301 is provided with a slit portion 301S, and when the slit portion 301S moves to a predetermined retraction distance, the photosensor 316 transmits light as shown in FIG. Stops. Hereinafter, this position is referred to as a home position.
[0056]
On the other hand, when a signal that the sheet S enters the sheet processing apparatus 300 is input from the printer main body 100, the jogger motor M rotates, the slide guides 301 and 302 move inward, and the sheet that enters as shown in FIG. Stop at a position wider than the width of S by a predetermined amount d. At this position, the slide guide 301 is in a state where the stopper 301b abuts against the guide pin 313a and cannot move further inward. Hereinafter, this position is referred to as a standby position. In this standby position, the side surface of the slide guide 301 becomes the reference position for the alignment operation.
[0057]
Here, in the present embodiment, when the size (width) of the sheet S is the maximum size that can be passed, the standby positions of the slide guides 301 and 302 are set so that the gaps on both sides are equal to or larger than the predetermined amount d. Is set.
[0058]
When aligning a narrower sheet than this, the slide guide 302 moves to the right by an amount corresponding thereto, so that the left gap at the standby position shown in FIG. . On the other hand, in this case, the gap between the sheet and the slide guide 302 widens by half the amount that is narrower than the predetermined amount d.
[0059]
On the other hand, after the alignment in the width direction is performed by the slide guides 301 and 302 as shown in FIG. The sheet S is brought into a movable state in the sheet conveyance direction. Thereafter, as shown in FIG. 5 (b), the paddle 322 rotates once while contacting the upper surface of the sheet S in the clockwise direction around the paddle shaft 350, whereby the sheet S is abutted against the reference wall 323. Align.
[0060]
These operations enable alignment in the sheet conveying direction and the width direction. In order to maintain such an aligned state, a lever 400b provided with a friction member 400a as shown in FIG. 7 described later is provided in the vertical direction in the vicinity of the right end surface of the aligned sheet as shown in FIG. A stamp means 400 is provided for pressing the aligned sheet S after moving to.
[0061]
Then, after the aligning operation is completed by the stamp unit 400, the sheet in the aligned state is moved by pressing the upper surface of the sheet before the next entering sheet contacts the aligned sheet. Therefore, the alignment is prevented from being disturbed.
[0062]
Note that after the alignment of the first sheet is completed in this way, the second sheet is conveyed. In this case, the discharge roller pair 330 is separated when the second and subsequent sheets are conveyed. Therefore, when the trailing edge of the sheet S completely passes through the staple roller pair 320, the sheet returns to the direction opposite to the conveyance direction by its own weight and moves toward the reference wall 323. Since the alignment operation from here is exactly the same as that of the first sheet, description thereof is omitted.
[0063]
Then, such an operation is repeated to perform an operation of aligning the last (nth) sheet (Sn) of one job, and each reference pin 304 provided on the slide guide 302 moves the left side surface of the sheet along the slide guide 301. 6 in a state where the movement of the slide guide 302 is stopped, the position on the right side of the rear end is stapled by a small stapler H located on the right side of the rear end of the sheet bundle.
[0064]
Here, according to this configuration and operation, during the alignment operation of each sheet, the slide guide 301 stops and does not move at the reference position, and only the slide guide 302 moves and the left end portion of each sheet moves to the reference position. Thus, the binding process by the stapler H fixedly arranged on the slide guide 301 side is performed accurately and reliably.
[0065]
Furthermore, even when the width of each sheet carried in one job varies or when the sheet size changes within one job, for example, from LTR to A4, the position of the left end of each sheet is made uniform. Therefore, the finish of the binding process by the stapler H becomes accurate and beautiful, and an excellent effect is obtained.
[0066]
On the other hand, when the stapling operation is completed in this way, as shown in FIG. 5C, the arm 330c rotates in the clockwise direction, so that the discharge upper roller 330a supported on the arm 330c is moved downward. As a result, the discharge roller pair 330 is formed, and at the same time, the discharge roller pair 330 is driven to start the rotation of the discharge upper roller 330a and the discharge lower roller 330b. As a result, the sheet bundle S is sandwiched between the discharge roller pair 330 and conveyed onto the second intermediate stacking unit 300 </ b> C formed by the slide guides 301 and 302.
[0067]
After that, when the sheet bundle S is completely discharged from the discharge roller pair 330, the jogger motor M is rotationally driven to move the slide guide 302 from the state shown in FIG. When the slide guide 302 starts to move, the slide rack 312 moves to the right in FIG. 6 on the slide guide 301 side, and the slide guide 301 itself does not move immediately.
[0068]
When the position of the slide guide 302 passes the standby position shown in FIG. 3, the square hole portion 312a of the slide rack 312 comes into contact with the end surface of the embossed portion 301a of the slide guide 301, and the slide guide 301 is moved to the right side in FIG. The movement starts and both slide guides 301 and 302 move.
[0069]
After this, when the distance between the slide guides 301 and 302 becomes near or wider than the width of the sheet, the stapled sheet bundle supported by the slide guides 301 and 302 is as shown in FIG. The sheet falls downward and is stacked on the sheet stacking unit 325. The above is the configuration and the series of operations of the printer main body and the sheet processing apparatus in the present embodiment.
[0070]
As described above, in this embodiment, the sheet processing apparatus 300 is mounted on the upper portion of the printer main body 100, and the sheet is reversed by switching the conveyance path of the sheet discharged from the printer main body 100 with the flapper 150. It can be discharged and loaded.
[0071]
Here, the sheet processing apparatus 300 is mounted on the upper portion of the printer main body 100 in this way, and the sheets are reversed and discharged and stacked, whereby the sheets on which images have been formed are discharged in the order of pages without providing a switchback mechanism. Can be loaded. Further, there is no inconvenience that the sheet interval has to be widened for switchback.
[0072]
As described above, in the printer main body 100 that discharges the sheet to the upper surface of the apparatus, the sheet processing apparatus 300 is provided above the discharge unit on the upper surface of the apparatus main body, and the sheet is reversed or in a reversed state. By selectively performing an operation of discharging the sheet stacking unit 325 after processing the sheet, the configuration of the sheet processing apparatus 300 can be simplified, and the sheet processing apparatus 300 and the sheet processing apparatus 300 are provided. In addition, the installation area and cost of the printer main body 100 can be reduced.
[0073]
In the above description, only the slide guide 302 operates and the slide guide 301 does not operate during the sheet alignment operation. However, the slide guide 301 may operate during the sheet alignment operation. In this case, for example, the slide guide 301 can be realized by using the same configuration as the slide guide 302.
[0074]
Furthermore, although the two slide guides 301 and 302 are configured to operate when the sheet after the alignment operation is dropped downward, only one of the slide guides 301 and 302 may be configured to operate when the sheet S is dropped downward.
[0075]
In the description so far, the case where the binding process is performed as the process for the sheet has been described, but according to this configuration, the puncher for punching the sheet or the sheet for performing the process of creating a sheet bundle by gluing the sheet. The same effect can be obtained with the processing apparatus.
[0076]
Incidentally, FIG. 7 is a view showing the structure of the stamp means 400 described above which is an alignment deviation prevention means. As shown in FIG. 7, the stamp means 400 is provided with a friction member 400a at the tip and a shaft 400c. An arm lever 400b that is a pivotable pressing member as a fulcrum, a solenoid 401 that is a releasing means for rotating the arm lever 400b to release the pressing operation of the arm lever 400b, and an arm lever 400b in the direction of an arrow 402, that is, A torsion coil spring (not shown) that urges the sheet S in a direction to press the sheet S in the direction of the slide guide 301 is provided.
[0077]
Here, during the discharging operation, the arm lever 400b of the stamp unit 400 is positioned outside the sheet conveyance path through which the succeeding sheet Sb passes the aligned preceding sheet Sa as shown in FIG. 7 by the force of the torsion coil spring. In other words, the pressing is performed at a position outside the sheet passing range.
[0078]
As a result, the arm lever 400b can be prevented from coming into contact with the succeeding sheet Sb to be discharged next, and the preceding sheet Sa that is already held in alignment with the second intermediate stacking unit 300C is the succeeding sheet. It is possible to prevent extrusion by Sb.
[0079]
On the other hand, when the succeeding sheet Sb is completely discharged, the succeeding sheet Sb moves in the direction of the arrow 403 shown in FIG. And while the succeeding sheet Sb moves in this way, the solenoid 401 is turned on. As a result, the arm lever 400b rotates in the direction of the arrow 404 shown in FIG. 8B, and as a result, the succeeding sheet Sb enters under the arm lever 400b.
[0080]
Thereafter, after the alignment in the sheet conveyance direction by the paddle 322 is performed, the slide guide 302 returns to the standby position. In this embodiment, however, the slide guide 302 returns to the standby position to prepare for the subsequent sheet carry-in. The solenoid 401 is turned off before the process is completed. As a result, the arm lever 400b presses the preceding sheet Sa again, and as a result, the preceding sheet Sa can be prevented from being pushed out by the subsequent sheet Sb that is subsequently conveyed.
[0081]
(Full load detection with full load detection flag)
Next, the movement of the full load detection flag will be described.
[0082]
As shown in FIG. 9 (partially enlarged view of FIG. 5B), when the full load detection flag 600 is lifted by the arm 330c as the driving means, the photosensor 602 changes from light shielding to translucent. Therefore, when the full load detection flag 600 is detected in the slide guides 301 and 302, that is, when the sheets are stacked on the second intermediate stacking unit 300C, the full load detection flag 600 is detected in software. Do not. When the sheet is ejected, the arm 330c is lowered downward by a stepping motor (not shown), and after the sheet bundle is ejected, the sheet fullness is viewed at a predetermined timing. Is detected as being full, the sheet on the sheet stacking unit 325 is detected to be full.
[0083]
However, in the case of a sheet stack in which the slide guides 301 and 302 are simply retracted to the position shown in FIG. 4A, the full load detection flag 600 is always in a downward state, and the constant sheet stacking unit 325 I'm watching the full load. While the maximum length sheet to be discharged is pushing the full load detection flag 600 during discharge, the full load detection flag 600 is in the transmission state during that time, and the full load is detected, but at least the sheet is full. When it is confirmed that the full load detection flag 600 is transparent for a time longer than the time when the detection flag 600 is pushed up during discharging, the full load detection flag 600 is made full and the loading is finished.
[0084]
As described above, according to the present embodiment, when the sheets are stacked on the second intermediate stacking unit 300C, the full load detection flag 600 is rotated using the arm 330c as a driving unit, and the full load detection flag 600 is set. By configuring the lower surface 701 to function as an upper guide for guiding the sheet introduced into the second intermediate stacking unit 300C, sheet conveyance jam at the time of carrying the sheet into the second intermediate stacking unit 300C is reduced. be able to.
[0085]
[Second Embodiment]
Next, a second embodiment of the present invention will be described. Note that the schematic configurations of the image forming apparatus main body and the sheet processing apparatus are substantially the same as those in the first embodiment described above, and thus the description thereof is omitted here.
[0086]
In the present embodiment, the full load detection flag 600 is configured such that the rotation angle can be changed at a plurality of locations by a driving means (not shown). When the sheets are stacked on the second intermediate stacking unit 300C, the optimum gap amount t shown in FIG. 10 that is optimal for sheet conveyance can be substantially maintained even when a plurality of sheets are stacked as shown in FIG. Like that. Therefore, the rotation amount of the average full load detection flag 600 predicted in advance every time the sheet is discharged is driven by a driving unit (not shown). Even when the number of sheets stacked on the second intermediate stacking unit 300C is different, a guide for carrying in the sheet is formed by the full load detection flag 600 under substantially the same conditions, so that the sheet conveyance jam can be further reduced. .
[0087]
Needless to say, a detecting means for detecting the thickness of the sheet bundle may be provided, and the position of the full load detection flag may be controlled based on the data.
[0088]
[Third Embodiment]
Next, a third embodiment of the present invention will be described. Note that the schematic configurations of the image forming apparatus main body and the sheet processing apparatus are substantially the same as those in the first embodiment described above, and thus the description thereof is omitted here.
[0089]
In the present embodiment, as shown in FIG. 11, when the sheet is carried in, the gap amount t is maintained constant, and after being conveyed to the second intermediate stacking unit 300C, the sheet is aligned by the slide guides 301 and 302. Before, the full load detection flag 600 is set to a gap amount t = 0 as shown in FIG. 12, and the upper surface of the sheet bundle at the time of alignment by the slide guides 301 and 302 is urged by the weight of the full load detection flag 600. This serves to stretch the curl of the sheet curled at both ends in the width direction, thereby improving the alignment.
[0090]
【The invention's effect】
As described above, according to the present invention, the sheet is guided by the full load detection flag even when the sheet is curled upward when the sheet is carried into the second intermediate stacking unit. It is possible to reduce sheet jam at the carry-in portion to the intermediate stacking unit 2.
[0091]
In addition, the full load detection flag sequentially changes the rotation angle according to the number of sheets carried on the second intermediate stacking unit, thereby changing the gap amount of the sheet carrying unit to the second intermediate stacking unit. Further, it is possible to further reduce sheet jam at the carry-in portion to the second intermediate stacking portion.
[0092]
Further, when aligning the sheet width direction edge by the second intermediate stacking unit, the upper surface of the sheet is sequentially urged by the full load detection flag, so that the second intermediate stacking unit moves the sheet width direction end at the time of alignment. Push in reliably and improve consistency.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing the overall configuration of a laser beam printer as an example of an image forming apparatus including a sheet processing apparatus according to the present invention.
FIG. 2 is a diagram illustrating the configuration of the sheet processing apparatus and the movement of each unit when a sheet conveyed from the printer main body is directed to the sheet processing apparatus.
FIG. 3 is a plan view and a side view of main parts of the sheet processing apparatus.
FIG. 4 is a diagram illustrating a state where a sheet bundle is dropped when a slide guide provided in the sheet processing apparatus is located at a home position.
FIG. 5 is a diagram for explaining the movement of each part in the processing operation of the sheet processing apparatus.
FIG. 6 is a diagram illustrating a state in which sheets are aligned by the slide guide.
FIG. 7 is a diagram illustrating a configuration of stamp means provided in the sheet processing apparatus.
FIG. 8 is a diagram illustrating a state of the stamp portion when the sheet is aligned.
FIG. 9 is a diagram illustrating a full load detection flag provided in the sheet processing apparatus according to the first embodiment.
FIG. 10 is a diagram for explaining a full load detection flag provided in the sheet processing apparatus according to the first embodiment.
FIG. 11 is a diagram illustrating a full load detection flag provided in the sheet processing apparatus according to the second embodiment.
FIG. 12 is a diagram illustrating a full load detection flag provided in the sheet processing apparatus according to the third embodiment.
FIG. 13 is an overall perspective view of a laser beam printer as an example of an image forming apparatus including a sheet processing apparatus according to the present invention.
[Explanation of symbols]
F ... Mold frame
F '... Sheet metal frame
H ... Stapler
M: Jogger motor
S ... Sheet
S1 ... sheet
100: Printer body
100A ... Laser beam printer
101. Image forming unit
120: Fixing device
121 ... Conveying roller
125 ... discharge section
130 ... discharge roller
200 ... Feed cassette
300 ... Sheet processing apparatus
300A ... casing part
300B ... 1st intermediate loading part
300C second intermediate loading section
300D ... Bent part
301, 302 ... slide guide (second intermediate stacking portion)
301S ... slit part
301a: Embossed part
301b ... stopper
303, 304 ... reference pin
305, 306 ... end face
310 ... slide rack section
312 ... slide rack
312a ... Square hole
313a ... guide pin
313b Guide pin
314: Spring
316 ... Photosensor
317 ... Step gear
320 ... Staple roller pair
322 ... Paddle
323 ... Reference wall
325 ... Sheet stacking unit
330 ... discharge roller pair
330a ... discharge upper roller
330b ... discharge lower roller
330c ... arm
330d ... cam surface
350 ... Paddle shaft
363: Inlet roller pair
390 ... Entrance sensor
391 ... Flag
392 Photosensor
400… Stamp means
400a ... friction member
400b ... lever
400c ... axis
401 ... Solenoid
600 ... Full load detection flag
600b ... cam surface
601: Center of rotation
602 ... Photo sensor
700 ... upper surface of the guide
701: Flag bottom surface

Claims (4)

In a sheet processing apparatus that processes sheets discharged from the image forming apparatus main body,
A first intermediate stacking unit that aligns a sheet conveying direction end against the wall;
Discharging means for discharging sheets from the first intermediate stacking unit;
A second intermediate stacking unit having a function of carrying in and supporting the sheet on the downstream side in the conveyance direction of the discharge unit and aligning a width direction end perpendicular to the conveyance direction of the sheet;
A sheet stacking portion below the second intermediate stacking portion in the direction of gravity;
A full load detection flag for detecting the full load of sheets in the sheet stacking unit;
Have
The full load detection flag has a rotation fulcrum above the sheet discharge port by the discharge unit, and can be rotated by the drive unit around the rotation fulcrum.
When the sheet is carried into the second intermediate stacking unit, the lower surface of the full load detection flag is rotated to a position that functions as an upper guide for guiding the upper surface side of the sheet carried into the second intermediate stacking unit. A sheet processing apparatus. When the sheets are carried into the second intermediate stacking unit, the fullness detection flag sequentially changes the rotation angle according to the number of sheets carried into the second intermediate stacking unit, so that the second intermediate stacking unit The sheet processing apparatus according to claim 1, wherein the gap amount of the sheet carry-in section to the section is varied. 3. The sheet processing apparatus according to claim 1, wherein when the second intermediate stacking unit aligns the end portions in the width direction of the sheet, the full load detection flag sequentially biases the upper surface of the sheet. An image forming apparatus having an image forming apparatus main body that forms an image on a sheet, and a sheet processing apparatus that performs processing on a sheet discharged from the image forming apparatus main body.
An image forming apparatus comprising the sheet processing apparatus according to claim 1 as the sheet processing apparatus.

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