JP5581681B2 - Paper stacking apparatus and image forming apparatus provided with the paper stacking apparatus - Google Patents

Description

  The present invention relates to a paper stacking apparatus used in an image forming apparatus such as a copying machine, a facsimile machine, a printer, and a multifunction machine of these, and an image forming apparatus including the paper stacking apparatus.

  The paper stacking configuration of the stacker, which is a large capacity paper stacking device, has a space for setting a dedicated carriage for loading paper when the front door of the stacker is opened, and the dedicated carriage is set there. On the dedicated carriage, there is a tray on which sheets can be stacked. After the carriage is set, the front door is closed, and when the tray rises to the sheet discharge port, the tray enters a standby state.

  However, when such a conventional paper stacking apparatus prints on coated paper, when the coated paper is discharged onto the tray on which the paper is stacked, the uppermost paper in the paper stack stacked on the tray is used. There is a risk that the discharged paper may stick to each other. If sticking occurs between the stack of stacked sheets and the paper that has been ejected, the sticking causes resistance, and the paper cannot be ejected smoothly, before it is completely ejected onto the tray. The next paper is ejected and collides, causing the paper to curl. After that, the paper continues to be ejected with the paper curled up, and the job ends or the paper cannot be ejected due to the collision. Clogged, jammed and job stopped. That is, there is a problem that the stackability of paper deteriorates.

  Japanese Patent Application Laid-Open No. H10-260260 includes a transporting means for transporting a sheet discharged from an image forming apparatus for the purpose of stably receiving a sheet even if the sheet size is slightly different due to a mechanism made up of simple and inexpensive parts. A pair of upper trays that receive the sheet conveyed by the conveying means, move the sheet horizontally, align the received sheet, and drop the aligned sheet downward; A pair of upper tray driving means for providing force, an electric unit for transmitting the driving force of the upper tray driving means to the upper tray, a lower tray for stacking sheets dropped from the upper tray, and a distance between the upper tray and the lower tray In order to maintain the value within a predetermined range, the post-processing apparatus includes a lower tray driving unit that moves the lower tray in the upper and lower directions.

  However, when printing on coated paper by receiving the sheets discharged from the image forming apparatus, aligning them, and dropping them, the stack of sheets stacked on the upper tray and the sheets of discharged paper are pasted. The paper cannot be prevented from sticking, and the paper is aligned and dropped onto the tray by the paper alignment member. Therefore, the problem that the stackability of the paper loaded on the tray deteriorates cannot be solved.

  Therefore, the present invention sets a cart on the stacker, the tray on the set cart rises to the paper discharge port, accurately aligns the discharged paper, and when the number of sheets loaded increases, If a paper stacker that can load paper is printed on coated paper and the coated paper is ejected onto the tray, the stack of paper stacked on the tray and the ejected paper The object is to prevent the sheets from sticking to each other so that they can be accurately stacked on the tray even when printing on coated paper.

Of the paper stacking apparatus of the present invention, the one according to claim 1 is
Stacking sheets discharged from a fixed position sequentially on a horizontal tray that can be raised and lowered, and as a sheet aligning means, a width direction aligning means that aligns the end surfaces of the sheets in a direction orthogonal to the discharging direction, In a paper stacking apparatus having a leading edge aligning means for aligning from the position of the leading edge of the paper,
The width direction aligning means includes a receiving portion that receives discharged paper and an aligning portion that aligns the paper,
The receiving portion and the aligning portion are provided so as to be orthogonal ,
Among the aligning means provided in the vicinity of the portion from which the paper is discharged and the aligning means provided on the downstream side in the paper discharge direction, the width direction aligning means provided with the receiving portion is the paper. to in the discharge direction, wherein the means der Rukoto align is provided on the downstream side.

According to a second aspect of the present invention, in the paper stacking apparatus of the first aspect,
Stacking sheets discharged from a fixed position sequentially on a horizontal tray that can be raised and lowered, and as a sheet aligning means, a width direction aligning means that aligns the end surfaces of the sheets in a direction orthogonal to the discharging direction, In a paper stacking apparatus having a leading edge aligning means for aligning from the position of the leading edge of the paper,
The width direction aligning means includes a receiving portion that receives discharged paper and an aligning portion that aligns the paper,
The receiving portion and the aligning portion are provided so as to be orthogonal,
The width direction aligning means provided with the receiving portion drops the paper discharged by a rotation operation so that the receiving portion escapes from the discharged paper, and reciprocates in a direction perpendicular to the paper discharging direction. Alignment in the width direction is performed by performing the operation for each sheet.

According to a third aspect of the present invention, in the paper stacking apparatus according to the first or second aspect ,
The rotation and reciprocation of the aligning member provided in the downstream side of the discharge direction before Symbol for paper, paper size, characterized in that to perform in a large size, such as A3, B4.

An image forming apparatus according to claim 4, characterized by comprising a sheet stacking apparatus according to any one of claims 1 to 3.

An image forming apparatus according to a fifth aspect is the image forming apparatus according to the fourth aspect , wherein the image forming apparatus is a copier, a printer, a facsimile, or a complex machine thereof.

  According to the present invention, even when printing on coated paper, it can be accurately stacked on the tray. In other words, since the receiving member is provided on the aligning member that aligns the discharged paper on the tray, when the coated paper is discharged onto the tray, the paper bundle stacked on the tray is discharged. Can prevent sticking between sheets and stack correctly.

1 is a diagram illustrating an example of an image forming apparatus to which the present invention can be applied. 1 is a diagram illustrating an example of a paper stacking apparatus that can be employed in the image forming apparatus illustrated in FIG. The perspective view which shows the front end alignment mechanism of the paper stacking apparatus which concerns on this invention Perspective view showing the same width direction alignment mechanism The top view which shows the structure of the other width direction alignment mechanism The conceptual diagram which shows the width direction alignment mechanism of FIG. 4 seeing from upper direction

  The paper stacking apparatus of the present invention sequentially stacks the paper discharged from a fixed position on a horizontal tray that can be raised and lowered, aligns the end face of the paper in the direction perpendicular to the paper discharge direction by the width direction aligning means, and discharges the paper The sheet stacking device aligns the position of the leading edge of the sheet on the side by the leading edge aligning means. The width direction aligning means includes a receiving portion that receives discharged paper and an aligning portion that aligns the paper, and the receiving portion and the aligning portion are provided so as to be orthogonal to each other. Since the receiving member is provided on the aligning member and the coated paper is supported by the receiving portion and discharged onto the tray, the sheet bundle stacked on the tray and the discharged paper can touch each other. This eliminates sticking between sheets, so that even when printing on coated paper, the sheets are accurately stacked on the tray.

  In addition, a width direction aligning means provided with a receiving portion is provided on the downstream side in the paper discharge direction so that the paper can be reliably received even if the paper crushes and the leading edge of the paper hangs down while being discharged onto the tray. The sheet stack stacked on the tray is prevented from sticking to the discharged sheet, and is accurately stacked on the tray.

  Furthermore, the amount of movement in the width direction can be minimized compared to rotating the width direction aligning means to drop the paper and moving the total width of the paper width and receiving part width in the paper width direction to drop the paper. , Prevents the width direction aligning member and the apparatus from becoming large in the width direction. Further, the width direction aligning unit performs the reciprocating motion in the width direction for each sheet, thereby aligning all the sheets with high accuracy.

  Furthermore, when the paper size is limited to a large size and printing is performed on normal size paper and small size paper, the aligning means provided on the downstream side in the paper discharge direction is not operated to reduce power consumption.

  1 and 2 are diagrams illustrating an example of an image forming apparatus to which the present invention can be applied. The present invention is not limited to the illustrated image forming apparatus, and can be applied to various apparatuses that perform image formation.

  In the figure, reference numeral 100 denotes a stacker body, which introduces paper discharged from the image forming apparatus X such as a copying machine from the direction of arrow A in the figure. The stacker of this example can select an operation mode of a proof discharge mode, a straight discharge mode, and a shift discharge mode. When the shift discharge mode is selected, the shift discharge mode is set to pass through the sheet conveyance path. This is an operation mode in which sheets are discharged and stacked on the shift tray 102.

  The paper is transported by the transport roller 1 and the shift paper discharge roller 11 and discharged to the shift tray 102. The entrance sensor S1 and the shift sheet discharge sensor S2 detect passage of the sheet. In the shift discharge mode, sheets are stacked at different shift positions on the shift tray 102. When the number of stacked sheets increases, the shift tray 102 is gradually lowered so that the sheets can always be stacked at a constant height. The configuration of such a paper stacking apparatus is generally already known.

  1 and 2, reference numeral 120 denotes a lower branch claw, and 121 denotes an upper branch claw. The structures of the lower branch claw 120 and the upper branch claw 121 are the same. Therefore, in FIG. 2, the configuration of the branching claw is shown in detail using the lower branching claw 120.

  As shown in FIG. 2, when the branching claw 120 faces downward and the sheet sent from the image forming apparatus by the guide plate 114 passes the upper surface side of the branching claw 120, the sheet passes through the guide plate 111 and passes through the upper conveyance path. Follow (arrow L1). Further, when the branch claw 120 faces upward and the sheet sent from the guide plate 114 passes the lower surface side of the branch claw 120, the sheet passes through the guide plate 113 and follows the lower conveyance path L3.

  The branching claws 120 and 121 are rotated by rotating the gears engaged with each other by a motor (not shown) and using each shaft as a fulcrum. A method of controlling the amount of rotation of the branch claws 120 and 121 by passing a filler (not shown) through the filler 126 can be employed.

  As described above, the stacker of this example can select the operation mode of the proof discharge mode, the straight discharge mode, and the shift discharge mode. The operation of each paper discharge mode will be described below.

<Proof delivery>
The proof paper discharge mode is an operation mode in which a sheet is guided and stacked on the proof tray 101 through the sheet conveyance path L1. The paper is transported by transport rollers 1 to 4 and discharged to the proof tray 101. The entrance sensor S1 and the proof discharge sensor S4 detect the passage of the sheet. When sheets are stacked on the proof tray 101 and are stacked up to the position of the full detection sensor S5, the job in the image forming apparatus is temporarily stopped until the sheets stacked on the proof tray 101 are removed.

<Straight delivery>
The straight sheet discharge mode is an operation mode in which the sheet is guided to another apparatus such as a stacker provided at the subsequent stage of the stacker through the sheet conveyance path L2. In FIG. 2, the paper is transported by transport rollers 1, 2, 5 to 10 and sent to another apparatus such as a stacker. The entrance sensor S1 and sensors S6 and S7 detect the passage of the paper.

<Shift paper ejection>
The shift discharge mode is an operation mode in which sheets are discharged and stacked on the shift tray 102 from the direction of arrow D through the sheet conveyance path L3. The paper is transported by the transport roller 1 and the shift paper discharge roller 11 and discharged to the shift tray 102. The entrance sensor S1 and the shift sheet discharge sensor S2 detect passage of the sheet. In this shift discharge mode, sheets are stacked at different shift positions on the shift tray 102.

  FIG. 3 is a perspective view showing a tip alignment mechanism. The leading edge aligning mechanism 70 is a mechanism for aligning the leading edge of the sheet discharged onto the shift tray 102, and includes a stopper 71 whose position can be adjusted in the directions of arrows H1 and H2. The stopper 71 is attached to a slider 72, and the slider 72 is slidably guided by a shaft 73 extending in the arrow H1 direction, as shown. The slider 72 is connected to a belt 76 that is stretched between pulleys 74 and 75. When the belt 76 is moved by the motor 77, the slider 72 moves in the arrow H1 direction together with the stopper 71, and the position thereof is adjusted.

  The slider 72 is provided with a shielding plate 78, and when the stopper 71 moves to the home position, the shielding plate 78 is detected by the optical home position sensor S3.

  FIG. 4 is a perspective view showing the width direction alignment mechanism. The illustrated width direction alignment mechanism 90 includes stepping motors 80 and 80 that control movement in the width direction (a direction that is perpendicular to the paper discharge direction and horizontal) and vertical movement, a stepping motor 81 that controls rotation, and a stepping motor 81. A gear 82 meshing with a built-in gear (not shown), a rotation shaft 83 to which the gear 82 is attached, a drive shaft 84 parallel to the rotation shaft 83, sliders 85 and 85 mounted on the rotation shaft 83 and the drive shaft 84, It has. Further, although a sensor for detecting the slider 85 is provided, the illustration is omitted. In order to show the rotation state of the rotating shaft 83, the gear 82 is provided with a filler 86, and this filler is also detected by a sensor (not shown).

  Then, the alignment members 87 and 87 provided on the slider 85 are driven by the above-described stepping motor so that the distance between them is changed widely, and these are rotated up and down, but the filler 86 is detected by the sensor. Is the home position, and the alignment member 87 is in the lowered position. The illustrated width direction alignment mechanism includes a receiving portion 88 made of a plate-like body for receiving discharged paper, together with an alignment portion 87 for aligning the paper, and the alignment portion 87 is configured to be positioned below the receiving portion 88. It is. Note that an arrow p in the drawing indicates the sheet conveyance direction.

  FIG. 5 is a plan view showing a configuration of another width direction alignment mechanism. The configuration is almost the same as that of the mechanism shown in FIG. 4 except that the stepping motor 80 drives the slider 85 with a belt 92 wound around a plurality of rollers 89.

  FIG. 6 is a conceptual diagram showing the width direction alignment mechanism of FIG. 4 as viewed from above, and shows the operation of this mechanism from when the paper P is discharged in the direction of the arrow p until the paper P is aligned. is there.

(1) First, the paper P is discharged from the paper discharge port of the image forming apparatus (not shown) in the direction of the arrow p in the drawing. At this time, since the discharged paper P is supported by the receiving portion 88 provided with the aligning member 87 that aligns the width direction, the paper P that has already been stacked on the shift tray 102 is not touched. This state is shown in FIG.
(2) Next, if it is detected that the paper P discharged on the shift tray 102 is ready to be stacked (for example, the paper runs out), the aligning member 87 is rotated by appropriate control. Then, the sheet P falls onto the shift tray 102 as the receiving portion 88 escapes. This state is shown in FIG.
(3) Then, when the aligning member 87 performs the width shifting operation to the edge of the paper P, the bundle of the paper P is aligned in the width direction. This state is shown in FIG.

  That is, by providing the receiving portion 88, the paper P is discharged while being supported by the receiving portion 88, and the bundle of the paper P stacked on the shift tray 102 and the discharged paper P are not touched. In addition, the width direction can be aligned by performing a reciprocating motion for each sheet in a direction orthogonal to the paper discharge direction. Therefore, it is possible to prevent the sheets from sticking to each other and accurately align them on the shift tray 102 even when printed on coated paper.

  Further, the receiving portion 88 and the aligning portion 87 are arranged in a plane orthogonal to each other, so that the receiving portion 88 escapes from the discharged paper P in order to drop the discharged paper P. Since the aligning portion 87 is parallel to the end surface of the paper P when the sheet is rotated, the aligning portion 87 is reliably brought into and out of contact with the end surface of the paper P stacked on the shift tray 102 to align the bundle of the paper P. be able to. Note that it is preferable to control the rotation and reciprocation of the aligning member 87 as described above when the paper size is large, such as A3 or B4.

1 to 10: Conveying roller 11: Shift discharge roller 70: Tip alignment mechanism 71: Stopper 72: Slider 73: Shaft 74, 75: Pulley 76: Belt 77: Motor 78: Shielding plate 80, 81: Stepping motor 82: Gear 83: Rotating shaft 84: Drive shaft 85: Slider 86: Filler 87: Alignment member 88: Receiving portion 89: Roller 90: Width direction alignment mechanism 92: Belt 100: Stacker body 101: Proof tray 102: Shift trays 111, 113 114: Guide plate 120: Lower branch claw 121: Upper branch claw 126: Fillers L1 to L3: Sheet conveyance path S1: Entrance sensor S2: Shift discharge sensor S3: Home position sensor S4: Proof discharge sensor S5: Full detection sensor S6, S7: Sensor P: Paper p: Paper transport direction X: Image forming apparatus

JP 2000-095420 A

Claims (5)

Stacking sheets discharged from a fixed position sequentially on a horizontal tray that can be raised and lowered, and as a sheet aligning means, a width direction aligning means that aligns the end surfaces of the sheets in a direction orthogonal to the discharging direction, In a paper stacking apparatus having a leading edge aligning means for aligning from the position of the leading edge of the paper,
The width direction aligning means includes a receiving portion that receives discharged paper and an aligning portion that aligns the paper,
The receiving portion and the aligning portion are provided so as to be orthogonal ,
Among the aligning means provided in the vicinity of the portion from which the paper is discharged and the aligning means provided on the downstream side in the paper discharge direction, the width direction aligning means provided with the receiving portion is the paper. sheet stacking apparatus according to claim means der Rukoto aligning provided in the downstream side in the discharge direction of the. Stacking sheets discharged from a fixed position sequentially on a horizontal tray that can be raised and lowered, and as a sheet aligning means, a width direction aligning means that aligns the end surfaces of the sheets in a direction orthogonal to the discharging direction, In a paper stacking apparatus having a leading edge aligning means for aligning from the position of the leading edge of the paper,
The width direction aligning means includes a receiving portion that receives discharged paper and an aligning portion that aligns the paper,
The receiving portion and the aligning portion are provided so as to be orthogonal,
The width direction aligning means provided with the receiving portion drops the paper discharged by a rotation operation so that the receiving portion escapes from the discharged paper, and reciprocates in a direction perpendicular to the paper discharging direction. A sheet stacking device that performs alignment in a width direction by performing an operation for each sheet. The paper stacking apparatus according to claim 1 or 2 ,
The rotation and reciprocation of the aligning member provided in the downstream side of the discharge direction before Symbol for paper, sheet stacking device paper size is characterized by causing performed when the large size such as A3, B4. An image forming apparatus comprising the paper stacking device according to claim 1. 5. The image forming apparatus according to claim 4, wherein the image forming apparatus is a copier, a printer, a facsimile, or a complex machine thereof .