JP4861050B2 - Paper discharge device and image forming apparatus - Google Patents

Description

  The present invention relates to a paper discharge device for stacking sheets after image formation, and an image forming apparatus including the paper discharge device.

  In an image forming apparatus that transfers the content according to the original image onto a sheet, the sheet discharged after the image formation has a convex shape whose center in the width direction is located above both side edges in order to increase the sheet discharge speed. It is discharged so that it is curved in the shape of an arch and accommodated in the paper discharge device. Among image forming apparatuses, in printing apparatuses that perform stencil printing or offset printing, moisture contained in ink or dampening water supplied to the surface of the plate does not actively bend the paper. By transferring to the printing surface, the printing surface of the paper after image formation swells and extends due to the absorption of moisture and curves into a convex arch shape.

  The image-formed paper curved in a convex arch shape is easy to entrain air on the back side of the printing surface while falling toward the paper output tray of the paper output device, which causes air turbulence and air resistance. Is large, and the behavior until it is placed on the paper discharge tray becomes unstable. As a result, the direction of both side edges may become inconsistent, and it may take time to move to the placement position. If the movement behavior is not stable due to the shape of the paper itself after image formation, if the printing surface of the loaded paper is undried, the ink on that surface will be loaded next after image formation The paper is rubbed by a sheet of paper, causing a defective image and adverse effects such as ink show-through.

  Therefore, in Patent Document 1, a pair of side fences that are rotatably supported by a paper discharge tray of a paper discharge device for the purpose of correcting the wrinkles of the paper after image formation curved in a convex arch shape. A support member for curving upward both sides of the paper in the width direction is fixed to the lower part of the sheet, and the form of the stacked paper is reversed by contacting the both sides of the paper in the width direction after image formation to the support member. An arch shape has been proposed.

  Patent Documents 2 and 3 describe a configuration in which an end fence is rotated to load and lift a sheet.

Japanese Patent No. 3688858 JP-A-7-309507 JP-A-57-195062

  In Patent Document 1, the side fence is configured to rotate outward. However, when taking out a sheet having a length shorter than the interval between the side fences, the stacking surface of the sheet discharge table and the stacked sheets are not separated. Since there is no gap in between, it is difficult to take out the stacked paper easily without fingers, and there is room for further improvement.

In Patent Documents 2 and 3, when the end fence is tilted, the paper stacked on the paper discharge stand is lifted, and a space can be formed between the stacking surface and the paper. Side), and the sheets aligned at the time of taking out the paper are distorted, making it difficult to take out.
SUMMARY OF THE INVENTION An object of the present invention is to provide a paper discharge device and an image forming apparatus that can easily take out stacked paper while suppressing disturbance of paper stacked in alignment with a paper discharge table.

In order to achieve the above-described object, according to the first aspect of the present invention, there is provided a paper discharge tray on which the paper after image formation to be discharged is stacked, and a front end of the paper disposed on the downstream side of the paper discharge direction on the paper discharge base. An end fence that abuts, a side fence that is disposed in a width direction of the paper discharge tray that intersects with the paper discharge direction on the paper discharge table, and provided on the paper discharge table, wherein at least one side fence is in an upright state and a fall state And a support member that is pivotally supported so as to occupy the sheet , and the side fence rotates in the outward direction of the paper discharge stand on the leading end side of the sheet at the lower portion of the side fence supported by the support member, and occupies a fall state It is characterized in that a paper lifting portion that sometimes lifts the side edge on the front end side of the paper is provided so as to be rotatable integrally with the side fence,

Paper lifting unit may have a sloped surface that is curved upward side edges of the sheet, inclined surface, it is characterized in that the area is formed so as to increase in accordance toward the sheet discharge direction.

In the invention of claim 2, in the paper discharge apparatus according to claim 1, wherein the support member is characterized by having a guide surface continuous with the inclined surface when the side fences occupies a standing state.

According to a third aspect of the present invention, in the paper discharge device according to the first or second aspect , the stacking of the paper discharge tray is from the rotation center of the side fence to the distance from the rotation center of the side fence to the lower end of the paper lifting portion. It is characterized in that the distance to the surface is set to be long.

According to a fourth aspect of the present invention, in the image forming apparatus that forms an image on a sheet and discharges the image-formed sheet to the sheet discharge apparatus, the sheet discharge apparatus is the discharge according to any one of the first to third aspects. It is a paper device.

According to the present invention, the side edge on the leading end side of the sheet is lifted when the side fence is rotated outwardly toward the sheet discharge stand and occupies a fall state on the leading end side of the sheet at the lower portion of the side fence supported by the support member. Since the paper lifting part is provided so as to be able to rotate integrally with the side fence, when the side fence is rotated, the paper loaded on the stacking surface of the paper discharge tray is lifted and is placed between the stacking surface and the paper. Since the space is formed, the sheet can be easily taken out. Further, even when the paper is lifted by rotating the side fence, it is possible to prevent the paper discharge alignment from deteriorating when the paper is picked up by contacting the other side fence and the end fence in a two-dimensional direction. Since the leading end side or the trailing end side of the sheet is lifted, it is possible to minimize the deterioration of the sheet discharge alignment.

According to the present invention, since the paper lifting portion has an inclined surface that curves the side edge of the paper upward, if the paper is stacked on the paper discharge table, the paper lifting weight is also added to the paper lifting portion. A force to hold the side fence in an upright state is applied, and the spread of the side fence in the paper width direction can be suppressed, and disorder of paper alignment can be prevented.

According to the present invention, since the inclined surface is formed so that the area thereof increases as it goes in the paper discharge direction, the edge of the inclined surface crosses the side edge of the stacked paper, and the support member and the paper are lifted. In addition to preventing the paper from entering the gap with the section, when the side fence is rotated, the space formed between the stacking surface and the paper is widened by the end fence, making it easier to take out the paper. . In addition, since the area of the paper lifting portion on the near side in the paper discharge direction is reduced, the amount of lifting from the center of the loaded paper is reduced, so that the disturbance of the loaded paper can be minimized and the The load is small, and it is possible to prevent the paper from being damaged while preventing the paper lifting portion from being damaged.

According to the second aspect of the present invention, the distance from the center of rotation of the side fence to the stacking surface of the paper discharge tray is longer than the distance from the center of rotation of the side fence to the lower end of the paper lifting portion. Since it is set, the side fence can be brought down to the inside of the paper discharge stand, and the storage property is improved.

According to the third aspect of the present invention, the distance from the rotation center of the side fence to the stacking surface of the paper discharge tray is longer than the distance from the rotation center of the side fence to the lower end of the sheet lifting portion. Since it is set, the side fence can be brought down to the inside of the paper discharge stand, and the storage property is improved.

  Reference numeral 4 denotes a plate making apparatus. The plate making apparatus 4 is arranged on the right side in the apparatus main body 100 located below the scanner apparatus 1. In the plate making apparatus 4, a stencil sheet 5 wound in a roll is pressed against a thermal head 7 by a platen roller 6 while being perforated and stenciled. 27 is conveyed. The pre-made stencil sheet is disposed in the center of the apparatus main body 100 and is an outer peripheral surface of a printing drum 8 (hereinafter referred to as “drum outer peripheral surface”) that is driven to rotate by a drum driving unit (not shown) constituted by a driving motor described later. It is conveyed to 8a. Then, the leading end of the base paper is clamped and locked to a base paper tip clamper 9 provided on the drum outer peripheral surface 8a, and the drum outer peripheral surface 8a is wound around the drum outer surface 8a. It is wound around the outer peripheral surface 8a.

  Reference numeral 11 denotes a stencil discharging apparatus for separating and transporting and storing used stencil sheets from the drum outer peripheral surface 8a. The plate discharging device 11 includes a plate discharging rollers 12 and 13 for peeling and transporting the used stencil sheet on the drum outer peripheral surface 8a, a compression plate 14 for compressing the transported plate, and a plate discharging storage box for storing the compressed plate. 15 is provided, and a plate discharging operation is performed by driving a plate discharging drive unit (not shown).

  A sheet indicated by reference numeral 20 is placed on a sheet feeding table 21 that constitutes a sheet feeding apparatus 44 disposed on the right side of the apparatus main body. The paper 20 is supplied with a conveying force from a paper feed base 21 by a roller 22 constituting a paper feed means, and is sequentially separated one by one by a separation roller 23 and a separation pad 24, and a press roller serving as a printing drum 8 and a printing pressure means. The paper is fed toward the printing section N formed between the printer 28 and the printer 28. The fed paper 20 is fed toward the printing unit N at a timing by a pair of registration rollers 25 and 26 disposed on the conveyance path between the separation roller 23 and the printing drum 8. The paper feed table 21 is usually set to a size capable of loading paper 20 up to A3 size.

  A press roller 28 constituting printing pressure means is disposed below the printing drum 8. The press roller 28 is rotatably supported by a contact / separation mechanism (not shown). This contact / separation mechanism is driven by a printing pressure drive unit composed of a known electromagnetic actuator such as a solenoid, so that the press roller 28 is synchronized with the rotation of the printing drum 8 so as to avoid the clamper 9 portion. The surface 8a is intermittently contacted and separated. In the stencil printing apparatus, the image 20 is formed by pressing the paper 20 fed by the registration rollers 25 and 26 against the stencil stencil sheet on the drum outer peripheral surface 8a by the contact / separation operation of the press roller 28. In this embodiment, the press roller 28 is exemplified as the printing pressure means, but a known pressure cylinder may be used as the printing pressure means.

  In the vicinity of the printing drum 8 downstream of the printing unit N in the paper conveyance direction, a peeling claw 29 for peeling the paper 20 from the drum outer peripheral surface 8a is disposed. A conveying belt device 30 that sucks and conveys the paper 20 printed by the printing unit N is arranged below the peeling claw 29. The sheets 20 that are sucked and conveyed by the conveyor belt device 30 are sequentially discharged and stacked on a paper discharge tray 51 that constitutes a paper discharge device 50 disposed on the left side of the apparatus main body 100.

  When the printing operation is started, the printing apparatus operates the plate discharging device 11 to peel and convey the used stencil sheet wound around the drum outer peripheral surface 8a. Next, while the scanner device 1 is operated to read the original, the stencil sheet 5 is conveyed toward the printing drum 8 as the stencil stencil sheet 52 while performing the piercing stencil on the stencil sheet 5 with the thermal head 7. The conveyed stencil stencil sheet 52 is cut into a predetermined length (length for one plate) by the cutter 10 and the tip thereof is locked by the clamper 9 on the drum outer peripheral surface 8a. The pre-made stencil sheet 52 is wound around and mounted on the drum outer peripheral surface 8a of the printing drum 8 that is rotationally driven by a drum driving unit (not shown) in accordance with the plate feeding operation.

  When the plate making operation is completed, the printing operation is executed. In the printing operation, the paper 20 loaded on the paper feed tray 21 is conveyed toward the printing unit N and is pressed against the drum outer peripheral surface 8a by the press roller 28 that makes contact and separation (printing pressure operation) in the printing unit N. As a result, the printed image is transferred. Then, the sheet 20 separated from the drum outer peripheral surface 8 a by the separation claw 29 is sucked and conveyed by the conveying belt device 30 and discharged and stacked on the sheet discharge table 51. Such a printing operation is repeated for the set number of prints, and when the set number of prints is finished, the printing process is finished.

  Next, the paper discharge device 50 will be described.

  As shown in FIG. 2, the paper discharge device 50 includes a paper discharge tray 51 on which the printed paper 20 discharged from the apparatus main body 100 is stacked, and a downstream side in the paper discharge direction indicated by an arrow A of the paper discharge tray 51. Are disposed on the end fence 52 that contacts the leading end 20a of the paper 20 and a pair of side fences 53 and 54 that are disposed in the width direction of the paper discharge tray intersecting the paper discharge direction A indicated by the double arrow B. The side fences 53 and 54 are rotatable by a shaft 57 and a hinge portion 58 extending in the paper discharge direction A so as to occupy the standing state shown in FIG. 5 and the collapsed state shown in FIGS. Support members 55 and 56 are provided.

  Each hinge portion 58 is provided on the support members 55 and 56, a pair of flanges 58a to which the shaft 57 is fixed, side fences 53 and 54 are provided, and a long hole 58c into which the shaft 57 is inserted is formed. Each of the pair of flange portions 58b is configured. Each long hole 58c is formed so as to extend in the paper stacking direction (vertical direction) in FIG. For this reason, each side fence can be displaced in the vertical direction with respect to the shaft 57.

  The side fences 53, 54 are extended from the apparatus main body 100 side toward the end fence 52, and, as shown in FIG. It is supported by support members 55 and 56 so as to be rotatable toward the inside of the paper discharge table. A shaft 70 is disposed in parallel with the shaft 57 at the upper portion of the hinge portion 58. Both ends of the tension coil spring 71 are hooked between the shaft 57 and the shaft 70 and urge the side fences 53 and 54 toward the support members 55 and 56. For this reason, the force in the direction in which the side fences 53 and 54 are held in the standing state shown in FIGS. 3 and 5 acts elastically. The side fences 53 and 54 are respectively formed with stoppers 85 that come into contact with the upper surfaces of the support members 55 and 56 to restrict the movement of the fences in the fall direction when the side fences 53 and 54 are tilted in the outer direction C of the paper discharge tray. .

  The discharge table 51 is formed in a box shape, and racks 61 and 62 are laid in the inner space in the discharge table width direction B as shown in FIG. The tooth portions 61 a and 62 a formed on the racks 61 and 62 mesh with a common pin-on 64 rotatably supported by a shaft 63 provided on the paper discharge table 51, and one rack is connected to the width of the paper discharge table. When moving in the direction B, the other rack is also moved in conjunction with it.

  The side fences 53, 54 lift both side edges 20b, 20c on the front end side of the paper 20 as shown in FIG. Correction portions 59 and 60 as lifting members are provided so as to be rotatable integrally with the side fences 53 and 54. In this embodiment, the paper discharge tray 51 is attached to the apparatus main body 100 such that the side fence 53 is located on the back side of the apparatus main body 100 and the side fence 54 is located on the front side of the apparatus main body 100. In this embodiment, the front side of the apparatus main body 100 is a work side where the apparatus user stands and takes out the paper 20 from the paper discharge tray 51.

  The correction units 59 and 60 have a substantially trapezoidal shape, and one surface located inward of the paper discharge tray 51 is curved toward the center of the paper discharge tray 51 so that both side edges 20b and 20c of the paper 20 are curved upward. It is formed as inclined surfaces 59a and 60a inclined downward. As shown in FIG. 4, the inclined surfaces 59 a and 60 a are formed so that the areas thereof increase as the paper discharge direction A is reached.

  The support members 55 and 56 have a substantially trapezoidal shape, and are extended from the apparatus main body 100 side toward the end fence 52 like the side fences 53 and 54. The support members 55 and 56 are fixed to the ends of the racks 61 and 62, respectively, so that the side fences 52 and 53 can be moved relative to each other in the sheet discharge table width direction B.

  One surface of the support members 55 and 56 positioned inward of the paper discharge tray 51 is in contact with substantially the entire area of both side edges 20b and 20c of the paper 20 toward the center of the paper discharge tray 51 so as to bend upward. It is formed as guide surfaces 55a and 56a inclined downward. The guide surfaces 55a and 56a are formed so as to form the same flat surface continuously with the inclined surfaces 59a and 60a of the correction portions 59 and 60 when the side fences 53 and 54 are in the standing state. .

  As shown in FIG. 5, the portions of the support members 55 and 56 that oppose the correction units 59 and 60 serve as space portions 66 that house the correction units 59 and 60 and communicate with the inside and the outside of the paper discharge tray 51. Is formed. The lower surface 66a of the space portion 66 is arranged such that when the side fences 53 and 54 are rotated around the shaft 57 that is the rotation center of the side fences 53 and 54 inside or outside the paper discharge tray 51, It is formed in an arc shape that is lower than the rotation trajectory of the lower tips 59b, 60b so as not to interfere with the lower tips 59b, 60b of the 60. The distance L from the rotation center of the shaft 57, which is the rotation center of the side fences 53, 54, to the stacking surface 51a of the discharge table 51 is the distance from the rotation center of the shaft 57 to the lower tips 59b, 60b of the correction units 59, 60. It is set to be longer than L1.

  Next, the operation of the paper discharge device 1 will be described.

  The paper 20 that is printed and discharged toward the paper discharge device 50 is bent into a convex arch shape whose both side edges 20b and 20c are lower than the center as shown in FIG. Then, it falls toward the paper discharge tray 51. The sheet 20 is guided and dropped at both side edges 20b and 20c by the inner side surfaces of the side fences 53 and 54, and the guide surfaces 55a and 56a of the support members 55 and 56 constituting the same continuous surface on the sheet discharge table 51. On the inclined surfaces 59a, 60a of the correction portions 59, 60, both side edges 20b, 20c are corrected into a concave arch shape positioned above the center portion and loaded.

  When taking out the paper 20 stacked on the paper discharge tray 51, as shown in FIG. 6, when the side fence 54 is pushed toward the paper discharge tray outer direction C, the stopper 85 comes into contact with the upper surface of the support member 54. Therefore, the rotation is restricted at a predetermined angle. The side fence 54 rotates about the shaft 57, and at this time, the lower ends 59 b and 60 b of the correction portions 59 and 60 rotate without interfering with the lower surface 66 a of the space portion 66. Further, when the side fence 54 is rotated in the discharge table outer side direction C, the correction portions 59 and 60 are also rotated integrally, so that the side fence 54 is stacked on the stacking surface 51A of the discharge table 51 and is positioned on the leading end side of the sheet 20. Since the side edge 20c is lifted and a space 80 is formed between the stacking surface 51a and the paper 20, the operator can put his hand and the paper 20 can be easily taken out. Even if the paper 20 is lifted by rotating the side fence 54, the side edge 20b of the paper and the paper tip 20a are in two-dimensional contact with the side fence 53 and the end fence 52, respectively. It is possible to prevent the deterioration of the paper discharge alignment. Since the correction portions 59 and 60 are formed at the end fence 52 side end side which is the paper front end side of the side fence 54, the paper front end 20a portion is lifted also in the side edge 20c of the paper 20, so Can be minimized. Further, when the stacking amount of the paper 20 on the paper discharge tray 51 increases, as shown in FIG. 3, the stacking weight of the paper 20 is also added to the correction units 59 and 60. Therefore, if the side fences 53 and 54 are pulled. Even when the sheet 20 is stacked beyond the height of the support members 55 and 56, the spread of the side fences 53 and 54 in the sheet width direction B is suppressed. It is possible to prevent paper misalignment.

  The correction units 59 and 60 have inclined surfaces 59a and 60a that bend the both side edges 20b and 20c of the paper 20 upward, and the inclined surfaces so that the area increases as the paper discharge direction A (end fence 52) is directed. Since 59a and 60a are formed, the side edges 59b and 60b of the inclined surfaces 59a and 60a cross the side edges 20b and 20c of the stacked paper 20, as shown in FIG. The sheet 20 can be prevented from entering the gaps 90 and 91 between the portions 59 and 60, and the space 80 formed between the stacking surface 51a and the sheet 20 when the side fence 52 is rotated ends. It becomes wide by the fence 52, and it becomes easier to take out the paper 20. Further, since the areas of the correction units 59 and 60 gradually become smaller near the apparatus main body 100 on the near side in the paper discharge direction, the amount of lifting of the central portion of the side edge 20c of the stacked paper 20 is reduced and loaded. Disturbance of the paper 20 is minimized, and the weight of the paper is not added to only a part of the correction units 59 and 60, and the paper 20 is prevented from being damaged while preventing the correction units 59 and 60 from being damaged. be able to.

  The distance L from the shaft 57 to the stacking surface 51a of the paper discharge tray 51 is set to be longer than the distance L1 from the center of the shaft 57 of the side fences 53, 54 to the lower tips 59b, 60b of the correction portions 59, 60. Therefore, as shown in FIG. 7, the side fences 53 and 54 can be tilted from the upright state indicated by the two-dot chain line to the sheet discharge table inner side D, which is the storage position indicated by the solid line. Will be better.

  In the present embodiment, the stencil printing apparatus has been described as an example of the image forming apparatus to which the paper discharge device 50 is mounted. However, the image forming apparatus is not limited to the stencil printing apparatus, and various printing apparatuses, electrophotography, and the like. An image forming apparatus that transfers and fixes a toner image onto the paper 20 by a method, a printer that ejects ink from nozzles, or a laser printer may be used. In addition, one correction unit is provided in each of the paper width direction on the front end side of the paper, but only one correction unit (on the front side of the apparatus main body) may be provided on the front side of the paper, and further on the rear end side of the paper. Alternatively, it may be configured to be provided at positions diagonal to the leading end side and the trailing end side of the sheet.

1 is a schematic front view of a stencil printing apparatus as an example of an image forming apparatus equipped with a paper discharge device of the present invention. 1 is a partially broken plan view illustrating a configuration of a paper discharge device according to an embodiment of the present invention. FIG. 3 is a front view illustrating a configuration of a paper discharge device viewed from the image forming apparatus side. It is the side view which looked at the side fence from the inside of a paper discharge stand. FIG. 6 is an enlarged view illustrating a sheet correction operation by a sheet lifting unit when sheets are stacked on a sheet discharge table. FIG. 6 is an enlarged view showing a state in which a sheet is lifted by a sheet lifting unit when the side fence is tilted from the standing state toward the outside of the sheet discharge table. FIG. 10 is an enlarged view showing an operation when the side fence is tilted from the standing state toward the inside of the paper discharge tray.

Explanation of symbols

20 Paper 20a Paper leading edge 20b, 20c Paper side edge 50 Paper discharge device 51 Paper discharge stand 52 End fence 53, 54 Side fence 55, 56 Support member 55a, 56a Guide surface 59, 60 Paper lifting part 59a, 60a Inclined surface 59b , 60b Lower end of the paper lifting part A Paper discharge direction B Output width direction L Distance from the rotation center to the output tray loading surface L1 Distance from the rotation center to the lower end

Claims (4)

A paper discharge tray on which the paper after image formation to be discharged is stacked, an end fence disposed on the downstream side in the paper discharge direction on the paper discharge tray, and a front end of the paper abutting, and paper discharge on the paper discharge tray Side fences respectively arranged in the width direction of the paper discharge tray crossing the direction, and a support member provided on the paper discharge table and rotatably supporting at least one side fence so as to occupy a standing state and a fall state And
A paper lifting portion that lifts the side edge of the paper front end side when the side fence occupies a fallen state on the paper front end side of the lower side of the side fence supported by the support member when the side fence is rotated outwardly and occupies a fallen state. , Provided to be rotatable integrally with the side fence ,
Prior Symbol sheet lifting unit has an inclined surface which is curved upwardly a side edge of the sheet leading end side, that the inclined surface is, the area in accordance toward the sheet discharge direction is formed so as to increase Characteristic paper discharge device. The paper discharge device according to claim 1.
The paper discharge device, wherein the support member has a guide surface that is continuous with the inclined surface when the side fence occupies an upright state. The paper discharge device according to claim 1 or 2,
The distance from the center of rotation to the stacking surface of the sheet discharge table is set to be longer than the distance from the center of rotation of the side fence to the lower end of the sheet lifting portion. Paper discharge device. In an image forming apparatus that forms an image on a sheet and discharges the image-formed sheet to a sheet discharge device.
The image forming apparatus according to claim 1, wherein the paper discharge device is the paper discharge device according to claim 1 .

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