JP2004352408A - Sheet stacking device, and image forming apparatus provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet stacking device capable of securely arranging and discharging sheets by collecting sheets stacked on a tray along the width for temporarily stacking the sheets to be arranged at a prescribed position, and securely discharging the sheets to a stacking stacker from the temporarily stacking tray. <P>SOLUTION: In this sheet stacking device, a support tray 203 to temporarily hold sheets for adding post-processes is continuously disposed with a discharged paper stacker 202 to contain the sheets from the tray to be stacked, and on the support tray 203, an arranging means 219 to arrange the sheets by the side edge to be collecting along the width, and sheet discharge means 205 and 206 to carry the sheets to the discharged paper stacker 202. In this constitution, a sheet projecting member 223 to flex the sheet perpendicularly to a carrying direction is provided on a passage to carry the sheet from the support tray 203 to the discharged paper stacker 202 to be movable between a projection position where it is projected to the passage and a retraction position where it is retracted. A moving means 227 for the sheet projecting member is also provided to position the sheet projecting member 223 to the retraction position when the sheets are arranged, and the projection position while the sheets are carried to the discharged paper stacker. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, sheets discharged from an image forming apparatus such as a copier, a printer, a fax machine, and a printing apparatus are stored in a stack tray at 1 o'clock, and subjected to post-processing such as punching, stamping, and stapling. 1. Field of the Invention The present invention relates to a sheet stacking apparatus that stacks and stores sheets one by one or sequentially in a bundle, and an image forming apparatus including the same.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2002-60118 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-179322 Generally, an image forming apparatus such as a copying machine, a printer, a facsimile, and an office printing machine uses a sheet after image formation as a stacker. It is loaded and stored. Recently, staples that bind sheets formed with images on these image forming apparatuses in a bundle or post-processing devices such as punches and stamps are attached to the sheets, and after these processes are performed according to the application. Processing devices (finisher) are widely used.
[0003]
In such a post-processing apparatus, it is necessary to temporarily store sheets from the image forming apparatus on a tray in order to perform post-processing, and to convey the post-processed sheets to a discharge stacker. The tray on which the sheets are temporarily stacked includes alignment means for orderly arranging the sheets in a predetermined position for post-processing, and unloading means for transferring the post-processed sheets (one sheet or bundle) to a discharge tray. Equipped. Usually, a pair of right and left alignment plates that press the sheet side edge and shift the width to the reference position are used as this alignment means. In the case of the center of the sheet, the left and right alignment plates move around the center, and the one side side reference is used. In this case, one matching plate (member) is fixed, and the other matching plate is configured to move. Further, as the configuration of the conveying means, a method is adopted in which a pair of rollers or a belt is rotatably provided on a temporary stacker, or a sheet pushing member for pushing out the rear end of the sheet is provided on a tray so as to be movable back and forth. In particular, when the sheets are stapled and discharged in a bundle, the method using the sheet pushing member is often used.
[0004]
The configuration of such a sheet extruding member is such that a sheet is stacked on a flat tray as known from Patent Documents 1 and 2, and the sheet is aligned while being hit with a matching plate from a side, and post-processing (refer to Patent Document 1). The sheet after stapling is moved on a tray by an extruding member (projection piece) and dropped and stored in a discharge stacker. On the other hand, when aligning sheets other than the above-mentioned documents, it is known that the tray is curved in a direction orthogonal to the direction in which the sheets are aligned in order to prevent the sheets from being curved and disturbed by the influence of curl or the like and aligned at the waist of the sheets. It is also known that when the sheet is carried out, the sheet is forcibly bent in a direction orthogonal to the conveying direction to reliably carry out the sheet. The former adopts a configuration in which the tray itself is curved, and the latter employs a means for providing a projecting guide such as a rib on the tray.
[0005]
[Problems to be solved by the invention]
However, in the tray on which sheets are temporarily stacked as a premise of the present invention, the following problem occurs because the direction in which the sheets are aligned and the direction in which the sheets are carried out are orthogonal. In other words, if the tray itself is curved in order to properly align curled or thin sheets, the sheets will bend when the sheet is carried out, causing poor conveyance or remaining trailing edges. Conversely, ribs must be placed on the tray to ensure that the sheet is carried out. When the protruding pieces are provided, the sheet is bent at the time of sheet alignment, and the sheet cannot be correctly aligned. Therefore, even when a curled sheet or a thin sheet is handled in the image forming process, the temporary stack tray is configured to be flat, and at the same time, the sheet is forced to be discharged from this tray in a flat posture, and the sheet alignment is performed. And leaving problems with emissions.
[0006]
Therefore, the present invention provides a sheet stacking apparatus that can reliably carry out a sheet from a tray on which sheets are temporarily stacked, and at the same time, does not adversely affect sheet alignment, thereby reliably aligning and discharging sheets. Is the main issue.
Another object of the present invention is to provide such a device with a small size and a simple structure at a low cost.
[0007]
[Means for solving the problem]
In order to solve the above-mentioned problem, the present invention arranges a support tray for performing post-processing on sheets and a discharge stacker for stacking and storing sheets from the tray in a continuous position, and aligns a sheet side edge with the support tray. And a sheet ejecting member for bending the sheet in a direction orthogonal to the conveying direction to the path for conveying the sheet from the support tray to the sheet discharging stacker. It is movably provided between a protruding position protruding on the path and a retracted position, and is positioned at a retracted position during sheet alignment and at a protruding position during sheet conveyance. In this way, at the time of sheet alignment, the sheets are aligned by a support tray that is flat or curved to a shape suitable for alignment, and at the time of transporting the sheets, the sheet ejecting member bends the sheets in a direction perpendicular to the transport, and securely presses the sheets to the discharge stacker with the stiffness of the sheets. It is possible to carry it out.
[0008]
In view of the above, a first aspect of the present invention provides a support tray on which sheets to be sequentially fed are placed, alignment means for pressing a sheet side edge on the support tray to align the sheet with a predetermined position, and A discharge stacker for storing sheets from the support tray, sheet discharge means for transferring the sheets on the support tray to the discharge stacker, and a protruding position where the sheet on the support tray bends and a distance from the sheet. A sheet ejecting member which is movable in and out of the retracted position, and a moving means of the sheet ejecting member which positions the sheet ejecting member at the retracted position when the sheets are aligned and at the projecting position when transferring the sheet to the discharge stacker. The above object can be achieved by the configuration of the sheet stacking device.
[0009]
Next, a second aspect of the present invention is provided with a post-processing means for performing post-processing such as stapling, punching, and stamping on the sheet on the supporting tray of the first aspect. And post-processing of the sheet.
[0010]
According to a third aspect of the present invention, in the configuration of the first or second aspect, a sheet ejecting member provided with a sheet discharging means on the support tray and movable in a sheet ejecting direction, and moving the sheet pushing member back and forth in the sheet ejecting direction. The sheet pushing member is configured to engage with the trailing end of the sheet so as to transport the sheet, whereby the transport of the bundle of sheets is reliably transported without wrinkles or the like. It is possible to do.
[0011]
According to a fourth aspect of the present invention, the sheet protruding member according to any one of the first to third aspects is provided at one or several positions in a sheet width direction orthogonal to a sheet unloading direction of the support tray. It does not bend in the conveying direction or bend in the conveying direction.
[0012]
According to a fifth aspect of the present invention, there is provided the sheet pushing member according to any one of the first to fourth aspects, wherein the sheet pushing member has a sheet pushing surface engaged with a trailing edge of the sheet on the support tray and a sheet pressing surface engaged with the upper surface of the sheet. With this configuration, the sheet on the support tray is pushed out while being pressed by the hook-shaped member at the rear end and the upper surface, so that the sheet does not warp upward.
[0013]
Next, a sixth aspect of the present invention provides a support tray on which sheets to be sequentially fed are placed, alignment means for pressing a side edge of the sheet on the support tray to align the sheet with a predetermined position, and connecting to the support tray. A sheet discharge stacker arranged to store sheets from the support tray, sheet discharge means for conveying the sheets on the support tray to the discharge stacker, and a sheet orthogonal to the sheet placed on the support tray. A sheet regulating member movable between a projecting position projecting above the support tray so as to form a bend and a sheet pressing position engaging with the uppermost sheet on the discharge stacker; And a driving means for moving between the sheet pressing position and the sheet pressing position, so that the above-described problem can be achieved. In particular, when the sheet regulating member conveys the sheet from the support tray to the sheet discharging stacker, the sheet is bent at the projecting position and is securely carried out onto the sheet discharging stacker. It is possible to prevent adverse effects due to sheet warpage when a sheet is pressed and the next sheet is carried in. Therefore, it is possible to reliably carry out the sheet and carry in the next sheet with a simple structure.
[0014]
According to an eighth aspect of the present invention, in the configuration of the sixth aspect, the sheet pushing member is configured to engage with the sheet at one or several places in a sheet width direction orthogonal to the sheet unloading direction of the support tray. This makes it possible to bend the sheet in the direction perpendicular to the conveyance direction and to reliably reach the discharge stacker.
[0015]
According to a ninth aspect of the present invention, the sheet discharging means and the sheet regulating member of the sixth aspect are configured to engage with the sheet at two positions in the sheet width direction orthogonal to the sheet unloading direction. Can be conveyed without any deviation.
[0016]
According to a tenth aspect of the present invention, the sheet discharging means and the sheet regulating means of the sixth aspect are connected to the same driving means, and the driving means and the sheet regulating means are connected via a delay transmission mechanism. It is possible to reduce the size of a drive device such as a drive motor and an electric mechanism.
[0017]
According to an eleventh aspect of the present invention, in addition to the configuration according to any one of the first to tenth aspects, there is provided a printing unit for forming an image on a sheet, and a sheet conveying unit for carrying out the sheet from the printing unit to the stacking device. Accordingly, it is possible to continuously perform from image formation to post-processing and paper discharge storage.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments.
FIG. 2 is an overall view of an image forming apparatus embodying the present invention, and FIG. 1 is an explanatory view of a main part thereof. 2, the image forming apparatus includes an image forming unit 100, a post-processing unit 200, an image reading unit 300, and a document feeding unit 350, and has a unit structure incorporated in an independent casing. By combining these units, they can be used for various purposes. In the drawing, the post-processing unit 200 is installed above the image forming unit 100, and then the image reading unit 300 and the document feed unit 350 attached thereto are installed above the processing unit 200. In order to reduce the installation space of the apparatus, each unit is sequentially stacked to form an image forming apparatus.
[0019]
First, the image forming unit 100 is provided with the following structure so as to be used as an output printer by being connected to a computer or to be used as a copying machine by being connected to an image reading unit 300 described later. In the casing 101, a paper feed cassette 110, a printing unit 140, a fixing unit 150, a transport path 130 for transporting the paper in this order, and a paper discharge path 160 are incorporated. Although not shown, the paper feed cassette 110 is incorporated in the casing 101 so as to be attached to and detached from the casing 101 so that predetermined sheets (sheets) can be stored therein. The paper feed cassette 110 is provided with a paper feed roller 120 at a position where the paper feed roller 120 is rotated in the counterclockwise direction in FIG. Claws are provided. Therefore, when the paper feed roller 120 is rotated, only the uppermost sheet is separated and fed to the transport path 130 side.
[0020]
The transport path 130 is provided with a transport roller 131 and a registration roller 132. Then, the sheet guided to the conveyance path 130 is sent to the registration roller pair 132 by the conveyance roller 131 and waits. A printing unit 140 is provided downstream of the registration roller 132. Various printing means are known, and for example, an ink jet printing method, a thermal transfer printing method, or an offset printing method can be adopted. The drawing shows a case where the electrostatic printing method is adopted. In the figure, reference numeral 141 denotes an electrostatic drum (photoreceptor), around which a laser beam transmitter for forming a latent image on the electrostatic drum, a developing device for attaching toner ink, and a charging device for transferring ink to paper are provided. Are located.
[0021]
Accordingly, a latent image is formed on the electrostatic drum by a laser transmitter in accordance with an image signal sent from a computer or the like, and toner ink is adhered on the latent image by a developing device, and waits at the position of the registration roller pair 132. The paper is fed out and the toner ink is sequentially transferred onto the paper. Reference numeral 150 denotes a heating unit which is composed of heating rollers pressed against each other by a fixing unit, and sends the toner ink on the sheet to the sheet discharging path 160 while fixing the toner ink.
[0022]
Discharge rollers 190 and 191 and a discharge stacker 192 are provided in a discharge port 161 at the end of the discharge path 160, and sheets are stacked on the discharge stacker 192 by the discharge rollers 190 and 191. I have. Therefore, the sheets (sheets) from the paper feed cassette 110 are subjected to predetermined printing by the printing unit 140 and fixed by the fixing unit 150, and then stacked and stored on the discharge stacker 192 from the discharge port 161. Become.
[0023]
Therefore, the paper discharge path 160 is provided with a connection path 162 that branches from the path toward the paper discharge port 161 and guides the paper to the post-processing unit 200 described later. The switching gate 170 directs the paper to the paper discharge port 161. Or the connection path 162 can be selected. That is, the switching gate 170 is formed by a solenoid so that the switching gate 170 rotates a predetermined angle in the counterclockwise direction from the state of FIG. 2 to block the path toward the paper discharge port 161 and at the same time feeds the sheet to the connection path 162 side. Driving means (not shown) is provided.
[0024]
"Post-processing unit"
The post-processing unit 200 includes a support tray 203 that temporarily holds sheets (sheets) sequentially discharged from the image forming unit 100, a paper binding staple that binds the sheets supported by the support tray by a predetermined number, and a sheet. Post-processing means 218 such as a punch for punching a predetermined position, a stamp for stamping a sheet, and an accumulation stacker 202 for storing the post-processed sheet are built in a casing 201. Then, paper discharge rollers 205a and 205b are disposed at a paper discharge port 204 of a carry-in path 207 connected to the connection path 162 of the image forming unit 100 so as to nip the paper and carry it out to the right side in FIG. Is temporarily arranged, and the stackers 202 are arranged below the support tray 203 so as to form steps.
[0025]
Therefore, the sheet on which the image is formed by the image forming unit 100 is guided from the connection path 162 to the carry-in path 207 of the post-processing unit 200, is stored in the support tray 203 from the paper discharge port 204, and is subjected to the post-processing on the support tray 203 Are stored in the stacker 202. Details of the post-processing unit will be described later.
[0026]
"Image reading unit"
In the illustrated image forming apparatus, an image reading unit 300 and a document feeding unit 350 are mounted above a post-processing unit. The image reading unit 300 includes a platen 302 for setting a document in a casing 301, a carriage 303 reciprocally movable along the platen 302, a light source 304, a mirror 305, a lens 306 mounted on the carriage 303, A conversion element 307 is incorporated. The carriage 303 is held on a guide rail 310 (see FIG. 2) fixed to the casing 301, and is connected to an endless belt 308 stretched between a pair of pulleys. The carriage 303 is configured to be movable in the left-right direction in FIG. 3 by a drive motor 309 connected to the pulley. The illustrated drive motor 309 is a pulse motor, and the endless belt 308 is a toothed timing belt to control the position of the carriage 303. It has become. Note that the carriage 303 shown in FIG. 3 has the chain line position set to the home position.
[0027]
Accordingly, the document set on the platen 302 receives a reading start signal, and the carriage 303 moves from the home position to the right side in FIG. 3, and in the course of the movement, light from the light source is reflected on the document surface and reaches the mirror 305. An image is formed on the photoelectric conversion element 307 via the lens 306, converted into an electric signal, and output. The photoelectric conversion element 307 shown in the drawing emits charges accumulated by reflected light from a document by a CCD (Charge Coupled Device) to the outside at a predetermined clock, and converts the electric signal as image data to the image forming unit 100 or an external computer. Will be sent to
[0028]
"Document feed unit"
A document feeding unit 350 is attached to the image reading unit 300 as an attachment. The document feed unit 350 includes a document feed tray 351, a sheet feed roller 352 that separates and feeds documents on the tray one by one, and a document fed from the sheet feed roller 352 to the image reading unit 300. The paper feed path 353 leads to the platen 302, and a paper discharge tray 354 that stores documents from the paper feed path 353.
[0029]
Reference numeral 355 denotes a backup plate provided at a (reading position) at a position facing the platen 302 in the paper feed path 353, and supports the document from the back side at the reading position to prevent image distortion. . In the drawing, reference numeral 356 denotes a pair of transport rollers provided in the paper feed path 353, and reference numeral 357 denotes a pair of discharge rollers connected to a drive motor. Therefore, if a document is set on the paper feed tray 351 and a start signal is sent, the documents on this tray are sequentially sent to the reading position of the paper feed path 353. Therefore, the carriage 303 of the image reading unit 300 is kept stationary at the position indicated by the solid line in FIG. 3 and sequentially reads the originals fed at the predetermined speed optically. The read original is stored on a discharge tray 354 via a discharge roller 357.
[0030]
"Structure of post-processing unit"
The post-processing unit 200 will be described in detail. A sheet on which an image is formed by the image forming unit 100 is guided from the connection path 162 of the unit 100 to the carry-in path 207 of the post-processing unit 200. A support tray 203 for temporarily holding sheets is disposed below the discharge port 204 of the carry-in path 207, and a stacker 202 is disposed further below the support tray 203 to support the sheet from the discharge port 204. It is configured to be transported to the tray 203 and then to the stacker 202.
[0031]
The illustrated support tray 203 and the stacking stacker 202 are configured as trays having a shape sufficient to place the sheets, and are disposed so as to be inclined such that the leading end side in the sheet discharging direction is higher, and regulate the end face of the sheet at the trailing end side. Stopper walls 203a and 202a are provided respectively. Therefore, the sheets from the sheet discharge port 204 are first conveyed out along the support tray 203, are regulated by the stopper wall 203a, and are sequentially stacked. Next, after the sheet is subjected to post-processing, the sheet is carried out onto the stacking stacker 202, and is regulated and stacked by the stopper wall 202a.
[0032]
The shape of the support tray 203 may be such that the sheet unloading direction (the left-right direction in FIG. 1) is formed longer (longer) than the sheet length, but the illustrated one is made smaller (shorter). The size is reduced. Therefore, all sheets or at least the longest size sheet are supported in a bridge shape on the rear end side by the support tray 203 and on the front end side by the stacker 202.
[0033]
Therefore, the discharge port 204 is provided with a pair of discharge rollers 205a and 205b for nipping and discharging the sheet, and a discharge belt 206 for guiding the sheet from the discharge roller onto the support tray 203. The paper discharge rollers 205a and 205b are formed of ordinary rubber or synthetic resin rollers, and are mounted at positions where the rotary shafts 210a and 210b mounted on the apparatus frame are pressed against each other. The discharge belt 206 is a rubber endless belt having projections formed on the surface thereof, which is a so-called caterpillar belt, and is stretched between the pair of pulleys 212 and 213. One pulley 212 is fixed to the rotating shaft 210b, and the other pulley 213 is supported by a bracket 214 rotatably attached to the rotating shaft 210b. Accordingly, the discharge belt 206 is configured such that the pulley 213 can swing vertically in FIG. 1 around the pulley 212, and the pulley 213 moves up and down according to the loaded amount while contacting the loaded sheets on the support tray 203. Become.
[0034]
A drive motor, which will be described later, is connected to the rotation shaft 210b, and rotates the paper discharge roller 205b and the paper discharge belt 206 clockwise in FIG. The paper discharge roller 205a that comes into pressure contact with the paper discharge roller 205b is a driven roller. In addition, a paddle 215 is provided at the position shown in FIG. 4 in the paper discharge port 204, and the paddle 215 is formed of a soft rubber plate-like piece and is fixed to a rotating shaft 216 attached to the apparatus frame. Therefore, the rotation of the rotation shaft 216 is controlled so as to move the sheet on the support tray 203 toward the stopper wall 203a, and details thereof will be described later.
[0035]
The support tray 203 is provided with an aligning member 219 for moving the stacked sheets in width so as to be movable in the front and back direction in FIG. 1 (a direction orthogonal to the sheet conveying direction). The alignment member 219 is mounted on the support tray 203 so as to reciprocate a plate-like member so as to engage with the side edge of the sheet and move the sheet in the direction perpendicular to the conveyance direction. The arranged racks are connected, and a pinion connected to a forward / reverse rotation motor is meshed with the rack to reciprocate.
[0036]
A post-processing unit 218 that performs post-processing on the stacked sheets is disposed on the support tray 203, and the illustrated one illustrates a stapling mechanism that binds a sheet bundle placed on the support tray 203. The stapling mechanism 218 incorporates a linearly connected needle (not shown), and a drive motor drives a former for bending the needle in a U-shape and a driver for inserting the needle in a U-shape into a sheet. The stapling is performed by using an anvil provided on the opposite side (back side) of the sheet by moving it well and driving the sheet bundle, and bending the tip of the needle provided on the opposite side (back side) of the sheet. In addition, as the post-processing means 218, a punch mechanism for punching a sheet or a stamp mechanism for stamping a sheet can be arranged on the support tray 203 instead of the stapling mechanism or together with the stapling mechanism. Are already known. Further, the support tray 203 is provided with a sheet pushing member 217 for carrying out the post-processed sheet to the collecting tray 202.
[0037]
The illustrated sheet pushing member 217 is provided movably on the supporting tray 203 by fitting the projecting sheet pushing pieces 217 into two long grooves formed in the supporting tray 203 in the left-right direction in FIG. The sheet push-out piece 217 has a shape having a sheet contact surface 217a that abuts on the trailing edge of the sheet bundle and pushes it out, and a sheet pressing surface 217b that is connected to the contact surface 217a and abuts on the upper surface of the sheet. It is configured. The sheet pushing member 217 is fixed to a transfer belt 218 provided on the back side of the support tray 203, and the transfer belt 218 is constituted by an endless belt stretched between pulleys 219 and 220 mounted on the back side of the support tray 203. ing. The driving of the transfer belt will be described later.
[0038]
A reference numeral 221a denotes a sensor lever provided in the sheet carry-in path 207 for detecting the leading end and the trailing end of the sheet, and a reference numeral 221 denotes a sensor for electrically detecting the operation of the sensor lever. The sheet stacker 202 is provided with a sheet presser 223 for pressing the uppermost sheet. The sheet presser 223 always presses the uppermost sheet in order to cause the sheet stacked on the stacker to partially rise due to curling or stapling, causing a collapse of the load and a malfunction of the full-state detection sensor.
[0039]
224 (FIG. 6) is a biasing spring for applying a pressing force to the sheet retainer 223, and biases the sheet retainer clockwise in FIG. When the sheet is sent from the support tray 202, the sheet retainer 223 needs to be retracted from the stacked sheets. For this reason, the sheet retainer 223 shown in the drawing rotatably supports the base end of the lever-shaped member on a shaft 225. Then, it swings between the pressed position in FIG. 6A and the retracted position in FIG. 6D. A cam follower pin 226 is provided integrally with the sheet retainer 223, and a cam 227 is engaged with the cam follower pin 226. The cam 227 is rotated against the spring 224 by the rotation of the cam 227 (counterclockwise in FIG. 6). The sheet presser 223 is moved from the pressed position to the retracted position. The driving of the cam 227 will be described later.
[0040]
The stacking stacker 202 is provided with a fullness detection lever 222 for detecting the uppermost position of the stacked sheets. In the illustrated stacking lever, an arm-shaped lever 222 is suspended from above the support tray 203 onto the stacking stacker 202. 228 are sensors for detecting the movement of the lever. The reason why the fullness detection lever 222 is suspended from above the support tray 203 onto the stacker 202 is that the sheet edge is detected as close to the center of the stacker as possible so that the edge of the sheet is stapled. This is because the load amount can be properly detected even when the swelling is caused by post-processing. Accordingly, when the fullness detection lever 222 is conveyed from the sheet discharge port 204 onto the support tray 203, it needs to be retracted from its transport path. The cam follower 230 is provided integrally with the base end portion.
[0041]
The cam follower 230 is engaged with a cam 231 fixed to a rotary shaft 216 to which the paddle 215 is mounted. The driving and control of the discharge roller 205, the discharge belt 212, the paddle 215, the sheet pushing member 217, the sheet pressing member 223, and the fullness detection lever 222 will be described. As shown in FIG. 5, the rotation of the drive motor M, which can be rotated forward and backward, transmits the rotation to a rotation shaft 210 to which a paper discharge roller 205b and a paper discharge belt 212 are attached via a transmission belt and gears. A one-way clutch 231 is built in between the rotating shaft 210 and the transmission gear attached to the rotating shaft 210, and transmits the rotation of the drive motor M that rotates forward and backward only in one direction indicated by an arrow.
[0042]
The drive motor M is adapted to be transmitted through a transmission gear train 232 to a rotating shaft 216 to which a paddle 215 is attached. A gear 234 attached to an intermediate shaft 236 shown in the figure and a gear 235 of the rotating shaft 216 meshing with the gear 234 are attached. Is intermittently transmitted. That is, the gear 235 is formed of a sector gear, and is partially disengaged from the gear 234 at a part of the outer periphery thereof.
[0043]
Further, a biasing spring 237 is bridged between the gear frame 235 and the apparatus frame so as to always rotate in one direction, and the rotation shaft 216 is fixed to the rotating shaft 216 so as to prevent the rotation by the biasing spring 237. A latch wheel 238 and a solenoid 239 that engages the wheel are provided. Then, when the solenoid 239 is energized and the actuator is separated from the latch wheel 238, the rotating shaft 216 is rotated by the urging spring 237, and the gear 235 meshes with the gear 234 connected to the drive motor M, and a rotational force is applied.
[0044]
In this state, when the power supply to the solenoid 239 is cut off, the actuator comes into contact with the outer periphery of the latch wheel and slides while the rotation shaft 216 makes one rotation, and the gear 234 and the gear 235 are disengaged. Locked. A cam 231 for retracting the paddle 214 and the fullness detection lever 222 is attached to the rotating shaft 216. Accordingly, the leading end of the sheet that has entered the carry-in path 207 with the drive motor M rotated is detected by the sensor 221 and is carried out of the discharge port 204 by the discharge rollers 205a and 205b and the discharge belt 206. After a predetermined time period based on the signal from the sensor 221, the solenoid 239 is energized to rotate the rotating shaft 216.
[0045]
Then, the cam 231 rotates in the time direction in FIG. 1 to rotate the cam follower 230 counterclockwise, and the fullness detection lever 222 integrally formed with the cam follower 230 also retreats above the support tray 203 around the rotation shaft 216. With the rotation of the rotation shaft 216, the paddle 214 attached thereto also rotates clockwise in FIG. 1 to feed the rear end of the sheet that has entered the support tray 203 to the stopper wall 203a side. On the other hand, a gear is transmitted to the transport motor M via an electromagnetic clutch 240 to a rotating shaft 241 to which a pulley 220 of the transfer belt 218 is attached.
[0046]
A sheet pushing member 217 is attached to the transfer belt 218. When the electromagnetic clutch 240 is engaged, the rotation of the drive motor M is transmitted to the rotating shaft 241 to move the sheet pushing member 217 to the right in FIG. When the rotation is reversed, the sheet pushing member 217 moves to the left side in FIG. A cam 227 of the sheet pressing member 223 is connected to the rotation shaft 241 via a gear train 242, and the cam 227 is rotated by the rotation of the rotation shaft 241 as shown in FIGS. 6A, 6B, 6C, and 6D. 3), the sheet pressing member 223 is moved from the sheet pressing position to the retracted position.
[0047]
At this stage, when the transport motor M is rotated in the reverse direction, the rotation of the rotation shaft 216 of the paddle 215 is not transmitted because the gears 234 and 237 are disengaged, and the paper discharge rollers 205a and 205b and the paper discharge belt 212 are also one-way clutches. 231 idles and rotation is not transmitted. On the other hand, a rotational force in the opposite direction is applied to the rotating shaft 217, and the transport belt 218 and the sheet pressing member 223 return in the order of FIGS. 6d, c, b, and a.
[0048]
The configuration of the sheet push-out member 217 will be described. The sheet push-out member 217 is formed by the projecting member having the sheet contact surface 217a and the sheet pressing surface 217b as described above, and is fixed to the transfer belt 218. Is configured to reciprocate, but the one shown in the drawing particularly has the following configuration.
[0049]
First, the sheet push-out member 217 is set to be stopped at a standby position (the position in FIG. 6A) slightly retreated from the stopper wall 203a of the support tray 203, and a limit sensor (not shown) for detecting the sheet push-out member 217 at this position. Z) is provided. In the illustrated embodiment, a stopper wall 203a is provided separately from the sheet pushing member 217 to regulate the trailing edge of the sheet on the supporting tray 203. However, the sheet pushing member 217 directly controls the trailing edge of the sheet on the supporting tray 203. May be regulated. The sheet pushing member 217 is connected to the electromagnetic clutch 240 in response to a processing end signal from the post-processing means 218 so that the driving force of the driving motor M is transmitted to the rotating shaft 241. With the rotation of the rotating shaft 241, the transfer belt 218 moves the sheet push-out member 217 from the state shown in FIG. 6A to the unloading position shown in FIG. 6D, and in this process, the sheets on the support tray 203 are stored on the stacker 202. You.
[0050]
The leading end of the sheet push-out member 217 is set to have a positional relationship of pressing the uppermost sheet on the stacker 202 at the unloading position. Therefore, when the sheet is stored on the stacker 202, the sheet pressing member 223 retracts to the state shown in FIG. 6D, but instead, the leading end of the sheet pushing member 217 presses the loaded sheet to cause a collapsed load state. Nothing.
[0051]
An embodiment in which the present invention is applied to the sheet stacking device of the sheet post-processing unit 200 will be described below. In the support tray 203, a sheet discharging unit that carries out the sheets placed on the tray to the sheet discharge stacker 202, an aligning unit that aligns the sheets placed on the tray, and the sheet on the tray is bent. A sheet protruding member is provided for each.
[0052]
As described above, the support tray 203 is formed of a plate-like material that supports the entire sheet (full length) or a part thereof, and is usually formed in a flat shape. The discharging means for carrying out the sheet on the tray 203 is constituted by the above-described sheet pushing member 217. As shown in the drawing, this discharge means provides a slit groove in the support tray 203 in the transport direction, and makes the protruding sheet pushing member 217 protrude from the back side of the tray (the side opposite to the sheet placing surface). Is fixed to the endless belt 218, and the endless belt may be turned by a driving means (a driving motor M in the drawing). In addition, the discharging means may be configured to nip the loaded sheet with a pair of rollers or a conveyance belt with the support tray 203 interposed therebetween and to discharge the sheet to the discharge stacker. It is also possible to constitute the discharging means by scraping the sheet on the support tray 203 with a paddle (a blade-like rotating body of an elastic member).
[0053]
As shown in FIGS. 1 and 3, the aligning means 219 is formed of a plate-like member which engages with a side edge (in the direction perpendicular to the direction of conveyance) of the sheet placed on the support tray 203. The aligning means 219 is provided in a pair on the left and right sides of the side edge of the sheet. When aligning the sheet on the basis of the center, the right and left sides are moved by the same amount to align the sheet at a predetermined position. When the alignment is performed in (1), one of the right and left is a fixed wall surface, and the other is configured to be movable. The one shown in the figure is a plate-shaped movable alignment plate 219 that abuts at least the center side edge of the sheet on the support tray 203 on the side reference, and a reference wall (not shown) formed integrally with the support tray 203 constitutes an alignment means. Make up. The movable aligning plate 219 has a rack gear integrally provided on the back side of the tray 203 (the side opposite to the sheet mounting surface), and a pinion that meshes with the rack is connected to a pulse motor that can rotate normally and reversely. Therefore, when the pulse motor is rotated forward and backward, the movable alignment plate 219 reciprocates by a predetermined amount, and the placed sheet on the support tray 203 is moved closer to the fixed reference wall. The pulse motor operates after a predetermined time (after the sheet is placed on the support tray) from the timing signal when the leading end or the trailing end of the sheet is detected by the sensor 221 of the above-described carry-in path 207.
[0054]
The sheet protruding member 223 is provided movably between a position protruding above the support tray 203 and a retreat position that is on the same plane as the sheet mounting surface of the support tray 203 or is separated from the same. The sheet protruding member is provided at one or more positions in the sheet width direction (transport orthogonal direction) so as to bend the sheet placed on the support tray 203 in the transport orthogonal direction. In the drawing, the sheet protruding member 223 is also used as the sheet pressing member 223 on the sheet discharge stacker 202. As described above, the sheet protruding member may be provided on the support tray 203 as an independent functional component, may also be used as a sheet pressing member as shown in the drawing, or may be also used as another functional component. The structure of the sheet pushing member with respect to the illustrated sheet pushing member 223 will be described. The sheet pushing member 223 is provided above the sheet discharge stacker 202 so as to be swingable about a shaft 225. As shown in FIG. 4, the illustrated sheet holding member is formed of arm-shaped members at two places in the sheet width direction, and the position and shape thereof are set to optimal values for curving the sheet in a wave-like shape by these members. The arm-shaped sheet pressing member 223 is urged by an urging spring 224 so that the leading end pressing portion 223a always presses the sheet on the discharge stacker 202. Further, a cam follower pin 226 is provided integrally with the sheet holding member 223 so as to engage with the cam 227. As shown in FIG. 6, the cam 227 is attached to the rotation shaft 227a, and the rotation of the rotation shaft 227a causes the sheet pressing member 223 to move above the discharge stacker 202 against the urging spring 224. That is, the sheet pressing member 223 is moved between a position retracted below the support tray 203 in FIGS. 6A and 6B and a position protruded above the support tray 203 in FIGS. 6C and 6D. It is configured to move by the cam 227 in the order of a), (b), (c), and (d).
[0055]
Next, the operation of the above configuration will be described. The sheet from the image forming unit 100 reaches the carry-in path 207 of the post-processing unit 200 and is conveyed to the paper discharge port 204. In this process, the leading edge of the sheet operates the sensor lever 221a and the sensor 221 detects this, thereby detecting the arrival timing of the leading edge of the sheet and controlling the subsequent operation. At this time, the above-described drive motor M is controlled to rotate the discharge roller 205b and the discharge belt 206 in the sheet discharge direction by a timing signal from the image forming unit 100. The sheet is transported to the right in FIG. 1 with the rotation of the paper ejection roller 205 b and the paper ejection belt 206, and the leading end moves along the support tray 203. When the sensor lever 221b detects the rear end (passing) of the sheet, the solenoid 239 is actuated a predetermined time after the timing, the engagement of the rotation shaft 216 with the latch wheel 238 is released, and the rotation shaft 216 is attached. The spring 237 rotates by a predetermined amount. Then, the gear 235 attached to the rotating shaft 216 meshes with the gear 234 connected to the driving motor M, and the rotation of the driving motor M is transmitted to the rotating shaft 216, and the paddle 215 attached thereto rotates clockwise in FIG. I do. The leading end of the paddle 215 contacts the sheet on the support tray 203 and moves the sheet to the left in FIG. 1, but the timing is such that the trailing end of the sheet comes into contact with the sheet after the sheet is completely discharged from the discharge belt 206 onto the support tray 203. The operation timing of the solenoid 239 is set.
[0056]
At the same time as the rotation of the rotation shaft 216, the cam 231 attached to the rotation shaft 216 engages with the cam follower 230 to swing the fullness detection lever 222 in the counterclockwise direction in FIG. Before entering and colliding with the fullness detection lever 222, the lever retracts upward from above the support tray 203. That is, the cam 231 of the rotating shaft 216 retracts the detection lever 222 above the support tray 203 before the sheet front reaches the full detection lever 222 from the timing when the sensor lever 221a detects the front end of the sheet. Is activated. Then, the paddle 215 of the rotating shaft 216 comes into contact with the sheet on the tray 203 after the rear end of the largest sheet to be used is carried out onto the support tray 203, and moves the sheet in the left direction in FIG. In a relationship. The trailing edge of the sheet moved by the paddle 215 enters between the paper discharge belt 206 and the support tray 203, and stops by hitting the stopper wall 203 by the rotation of the belt 206. When the sheets from the sheet discharge port 204 are stacked on the support tray 203 in this way, the alignment member 219 moves a predetermined amount in the front and back direction in FIG. 1 (the direction orthogonal to the sheet conveying direction) to shift the sheet side edge to the width. Align. At this time, the sheet is positioned at a predetermined position following the mounting surface of the support tray.
Such operations are sequentially repeated to stack sheets on the support tray 203. When the stacking of the predetermined sheets is completed, it is determined from the end signal from the image forming unit 100 or the fact that the next sheet does not reach the sensor lever 221a for a predetermined time or more, and the post-processing means 250 outputs a signal indicating the end of the processing or a predetermined end of the processing After the time, the electromagnetic clutch 240 connected to the drive motor M is operated to transmit the rotation of the drive motor M to the rotating shaft 241. Then, by the rotation of the pulley 219 attached to the rotating shaft 241, the transfer belt 218 rotates clockwise in FIG. 1, and the sheet pushing member 217 moves from the standby position in FIG.
[0057]
The post-processed sheet on the support tray 203 moves so as to be gradually extruded toward the stacker 202 as the sheet pushing member 217 moves. At this time, the cam 227 connected to the rotating shaft 241 by the gear train 242 engages with the cam follower pin 226 to swing the sheet pressing member 223 counterclockwise in FIG. 1 around the shaft 225 and the sheet pressing member 223 is integrated. Withdraw from the stacker 202.
[0058]
The sheet pushing member 217 pushes out the sheet on the support tray 203 onto the stacking stacker 202 before and after the sheet holding member 223 is retracted from the stacker 202, and the tip of the sheet pushing member 217 is stored in the stacker 202. The uppermost surface of the sheet is pressed downward.
[0059]
This operation will be described with reference to FIGS. 6A, 6B, 6C, and 6D. When the sheet pushing member 217 located at the standby position is in the state shown in FIG. 6A, the electromagnetic clutch 240 is actuated and the rotating shaft 241 is rotated. When rotated, it moves to the position shown in FIG. At the same time, the rotating shaft 227a connected to the rotating shaft 241 via the gear train 242 also rotates synchronously.
[0060]
In the state shown in FIG. 7B, the cam 227 of the rotating shaft 227a engages with the cam follower pin 226 to retract the sheet pressing member 223 above the stacker 202. Further, with the rotation of the rotation shaft 241, the sheet pressing member 223 retracts to a position protruding above the support tray 203 in FIGS. 6C and 6D, and curves the sheet to be discharged in a direction orthogonal to the discharge direction. The conveyance force of the sheet push-out member 217 is transmitted to the sheet by the bending of the sheet in the conveyance orthogonal direction, and the sheet is vigorously discharged to the stacker 202 side.
[0061]
When the sheet pushing member 217 is located at the carry-out position in FIG. 6A, the leading end of the pushing member 217 presses the sheet on the stacker 202 downward instead of the sheet pressing member 223 to hold the stacked sheets. The extruding member 217 is provided with a limit switch at a standby position. When the control pulse of the drive motor M reaches a predetermined number of pulses with the movement from this position, the drive motor M is rotated in a reverse direction. A control signal is issued, and the drive motor M rotates in the reverse direction. By the reverse rotation of the drive motor M, the sheet pressing member 223 moves (returns) in the direction of pressing the sheet on the stacking stacker 202 in the order of (d), (c), and (b) of FIG.
[0062]
【The invention's effect】
According to the present invention, as described above, a sheet protruding member movable between a projecting position at which a sheet is bent on a support tray on which the sheet is placed and a retracted position away from the sheet is aligned by the aligning means. The sheet is sometimes located at the retracted position, and is located at the projecting position when the sheet is conveyed by the sheet discharging means, so that when the sheet is carried out, the sheet curves and is reliably discharged to the sheet discharge stacker. Further, at the time of sheet alignment, the sheet can be aligned in a correct posture following the support tray without being curved. In addition, the sheet ejecting member is configured to press the stacked sheets on the sheet discharge stacker at the retracted position, so that the sheets are ejected to the support tray when the sheets are ejected while holding the stacked sheets on the sheet discharge stacker, and the sheets are reliably ejected. can do.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a main part showing an example of an embodiment of a sheet stacking apparatus according to the present invention.
FIG. 2 is an overall explanatory diagram showing an embodiment of an image forming apparatus according to the present invention.
FIG. 3 is an explanatory diagram showing a main part of an embodiment of the image forming apparatus according to the present invention.
FIG. 4 is a perspective view showing a driving mechanism of the sheet stacking apparatus according to the present invention.
FIG. 5 is a conceptual diagram showing a transmission system of the drive mechanism shown in FIG.
FIGS. 6A and 6B are explanatory diagrams of an operation state of the sheet pushing means shown in FIG. 1, wherein FIG. 6A shows a state of a standby position, FIG. 6B shows a state of being moved from the standby position, and FIG. The state of the carry-out position for carrying out the sheet to the stacking stacker is shown, and FIG. 4D shows the state of pressing and holding the sheet on the sheet stacking stacker.
[Explanation of symbols]
REFERENCE SIGNS LIST 100 Image forming unit 110 Paper feed cassette 130 Transport path 140 Printing means 150 Fixing means 160 Discharge path 200 Post-processing unit 202 Stacker 203 Support tray 205a Discharge roller 205b Discharge roller 206 Discharge belt 215 Paddle 217 Sheet push-out member 217a Sheet contact surface 217b Sheet pressing surface 218 Post-processing means 219 Alignment member 221 Sensor lever operation detection sensor 222 Full detection lever M Drive motor 223 Sheet pressing 300 Image reading unit 302 Platen 303 Carriage 307 Photoelectric conversion element 350 Document feed unit 351 Paper tray 354 Output tray

Claims (11)

A support tray on which sheets to be sequentially fed are placed;
Alignment means for regulating the side edge of the sheet on the support tray and aligning it at a predetermined position;
A discharge stacker that is arranged in tandem with the support tray and stores sheets from the support tray;
Sheet discharging means for transporting the sheet on the support tray to the paper discharge stacker; and a protruding position for forming a bend in a direction perpendicular to the direction of transport on the sheet placed on the support tray, and a retreat position separated from the sheet. A sheet protruding member movable between
A sheet stacking device comprising: a driving unit for driving the sheet protruding member to position the sheet protruding member at a retracted position when the sheets are aligned and to a protruding position when the sheet is carried out to the discharge stacker. 2. The sheet stacking apparatus according to claim 1, further comprising a post-processing unit that performs post-processing such as stapling, punching, and stamping on the sheet on the support tray. A sheet ejecting member provided on the support tray and movable in a sheet unloading direction;
3. A sheet stacking device according to claim 1, further comprising a driving means for moving said sheet pushing member back and forth in a sheet carrying direction, wherein said sheet pushing member engages with a rear end of the sheet to transfer the sheet. apparatus. 4. The sheet stacking apparatus according to claim 1, wherein the sheet protruding member is provided at one or several positions in a sheet width direction orthogonal to a sheet unloading direction of the support tray, and deflects the sheet in a conveyance orthogonal direction. . 5. The sheet pushing member according to claim 1, wherein the sheet pushing member comprises a hook-shaped member having a sheet pushing surface engaged with a trailing edge of the sheet on the support tray and a sheet pressing surface engaged with an upper layer surface of the sheet. The sheet stacking apparatus according to any one of the preceding claims. A support tray on which sheets to be sequentially fed are placed, alignment means for pressing a side edge of the sheet on the support tray to align the sheet with a predetermined position, and sheets arranged from the support tray which are arranged in tandem with the support tray and store sheets from the support tray A paper output stacker,
A sheet discharging means for conveying the sheet on the support tray to the discharge stacker, and a projecting position projecting above the support tray so as to form a sheet mounted on the support tray in a direction orthogonal to the direction of conveyance. A sheet pushing member movable between a sheet pressing position engaged with the uppermost sheet on the sheet discharge stacker, and a driving means for moving the sheet regulating member between the projecting position and the sheet pressing position. Integrated device. 7. The sheet stacking device according to claim 6, wherein the driving unit is controlled to move the sheet pushing member from a sheet pressing position to a projecting position when the sheet on the supporting tray is carried out by the sheet discharging unit. The sheet pushing member is configured to engage with the sheet at one or several places in a sheet width direction orthogonal to the sheet unloading direction of the support tray, and deflects the sheet in the conveyance orthogonal direction. 8. The sheet stacking apparatus according to 6 or 7. 7. The sheet stacking apparatus according to claim 6, wherein the sheet discharging means and the sheet pushing member are configured to engage with the sheet at two positions in a sheet width direction orthogonal to the sheet unloading direction. 7. The sheet stacking apparatus according to claim 6, wherein said sheet discharging means and said sheet pushing means are connected to the same driving means, and said driving means and the sheet regulating means are connected via a delay transmission mechanism. An image forming apparatus comprising: the sheet stacking device according to claim 1; a printing unit that forms an image on a sheet; and a sheet conveying unit that unloads a sheet from the printing unit to the sheet stacking device. .

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