JP2010149948A - Sheet feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet feeder capable of orderly aligning sheets ejected at a high speed, without requiring to adjust a position of a regulating plate for aligning the ejected sheets. <P>SOLUTION: This sheet feeder includes a sheet rear end butting surface on the upstream side in the sheet ejecting direction of an ejecting sheet tray 2A, and includes a sheet side end butting surface 32 on one side orthogonal to the sheet ejecting direction, and also includes a guide member 33 for lifting the sheet to the other one side orthogonal to the sheet ejecting direction. A sheet loading surface of the ejecting sheet tray is inclined to the upstream side in the sheet ejecting direction, and is also inclined to one side orthogonal to the sheet ejecting direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sheet feeding apparatus that sequentially feeds a sheet bundle one by one.

  An apparatus using sheet materials such as a copying machine, a printer, a sheet-through type scanner, and a fax machine includes a sheet feeding device for sequentially feeding sheets one by one. As an example of such a sheet feeding device, an ADF (automatic document feeding device) that feeds a read document used in a copying machine or the like to an image reading unit is known.

An apparatus such as a copying machine sequentially feeds sheets one by one from a sheet bundle by a sheet feeding device. In addition, a sheet discharge mechanism is provided that discharges a sheet that has been subjected to image formation, image reading, and the like onto a discharge sheet tray and forms a sheet bundle again. The discharge sheet tray has a pair of lateral restriction plates installed so that the position in the sheet width direction perpendicular to the discharge direction can be adjusted, and a tip restriction plate installed so that the position can be adjusted in the discharge direction. Is common. The three regulating plates as described above are configured to hold the three directions of the discharged sheets and to orderly arrange the discharged sheets.

However, in such a configuration, if the discharge sheets are arranged in a more orderly manner, it is necessary to adjust the position of the restriction plate so that the restriction plate is accurately aligned with the size of the sheet. However, even if such adjustment is made, the position of the discharged sheet is slightly shifted in the sheet width direction during feeding, so that a sheet that deviates from the accurately placed restriction plate rides on the restriction plate. There was a problem. Further, in a feeding device that feeds a sheet at a high speed, the sheet discharged at a high speed hits the front end regulating plate, and the discharged sheet stops in a state of being suspended for a moment due to the impact. Therefore, the next sheet is discharged while stopped in the stagnant state, and collides with the rear end of the stagnated sheet. This not only disturbs the alignment but also causes a problem of document breakage.

Therefore, in the image forming apparatus disclosed in Patent Document 1, the driven roller of the roller pair that discharges the sheet is disposed on the discharge sheet tray by being inclined with respect to the driving roller in the sheet conveyance direction. There has been proposed a technique for orderly aligning discharged sheets without using a regulating plate so that the sheet end surface is discharged along the reference surface. In addition, even if the sheet is thin and weak, it can be damaged by using a configuration in which the pressure applied by the driven roller is variable and the conveyance force in the direction toward the reference surface on the discharge sheet tray can be adjusted. There has been proposed a method of arranging the discharge sheets in an orderly manner.
Japanese Patent Laid-Open No. 07-112857

However, in the above proposal, since the sheet discharged obliquely with respect to the discharge direction is discharged while being in contact with the reference surface, in order to discharge without damaging the sheet, adjustment of the pressing force of the driven roller is performed. Becomes indispensable. However, trial and error are required to obtain a pressure that matches the characteristics of the sheet. At present, when the types of sheets are diversified, a pressure suitable for the sheet to be fed is processed each time different types of sheets are processed. It must be said that the work to find is troublesome.

Further, since the sheet is discharged obliquely and the sheet end surface is aligned with the reference surface, the discharged sheet slides and discharges with respect to the rotation of the roller pair for discharging the sheet. If the roller surface is changed by dust such as paper dust generated from the sheet after being used for a long time in such a state, the appropriate pressure is also changed, and the adjustment work is further troublesome.

By omitting the above points, the present invention solves the problems of the conventional discharge sheet aligning apparatus, and the sheet discharge direction and the end face alignment in the sheet width direction perpendicular to the discharge direction are satisfactorily performed. An object of the present invention is to provide a sheet feeding apparatus having a discharge tray with good workability, which does not need to be aligned in a state where the sheet is taken out.

In order to solve the above problems, a sheet feeding apparatus according to the present invention stacks and holds a feeding unit that feeds sheets one by one, a discharging unit that discharges sheets, and a sheet discharged from the discharging unit. In the sheet feeding device having a discharge sheet tray, the discharge sheet tray includes a rear end abutting surface that is an abutment of the rear end of the sheet on the upstream side in the sheet discharge direction, and a downstream side in the discharge direction of the discharged sheet. A guide member that lifts only one of the corners with respect to the sheet stacking surface of the discharge sheet tray, and a side that abuts the side end surface of the discharged sheet on the side opposite to the side on which the guide member is disposed The guide member is movable in a direction substantially perpendicular to the sheet discharge direction, and is inclined so that the upper end portion is higher on the downstream side in the sheet discharge direction. It is characterized by the a shape.

By using the present invention, it is not necessary to perform operations such as moving a regulating plate that regulates the discharged sheet, and the next sheet does not collide even during high-speed paper feeding, and it is not necessary to adjust a thin document. It is possible to provide a sheet feeding apparatus that can be used.

Embodiments of the present invention will be described below with reference to the drawings.

Embodiments of a sheet feeding apparatus according to the present invention and an image reading apparatus including the sheet feeding apparatus will be described with reference to FIGS. In the following description, the image reading apparatus having a U-turn path type conveying path will be described as an example. However, the present invention is not limited to the U-turn path type, and sheet bundles such as copying machines and fax machines are fed one by one. The present invention can be applied to various apparatuses that stack sheets discharged on a discharge sheet tray while aligning them. The illustrated configuration is schematic and is not limited to this configuration.

As shown in FIG. 2, the image reading apparatus includes a sheet placing table 2 </ b> B, a pickup roller 11, a feeding roller 12, a separation roller 13, a sheet feeding regulating plate 21, a conveyance roller pair 14, and a reading sensor. A pair 15, a discharge roller pair 16, and a discharge sheet tray 2A are provided.

Next, the configuration of the discharge sheet tray will be described with reference to FIGS. The sheet stacking surface of the discharge sheet tray 2A is inclined with respect to the apparatus installation surface. As shown in FIGS. 4 and 6, this inclination direction is inclined so that the downstream side in the paper discharge direction becomes higher with respect to the paper discharge direction, and the left side as viewed from the discharge sheet tray 2A side is low as shown in FIG. It is inclined to become.

  In the following description, the discharge sheet tray 2A is inclined when the apparatus is configured such that the left side is low when the apparatus is viewed from the discharge sheet tray 2A side. The same effect can be obtained.

The discharge sheet tray 2A has a side edge abutting member 32 that abuts one side edge of the document on the left side, and has a shape that pushes up the vicinity of the other side edge of the document on the right side. A guide member 33 is provided. Both the side end abutting member 32 and the guide member 33 can be adjusted in position in a direction substantially perpendicular to the paper discharge direction.

The operation of the image reading apparatus having the discharge sheet tray 2A of this embodiment will be described with reference to FIGS. As shown in FIG. 3 as viewed from above, the sheet S is placed on the sheet placing table 2 </ b> B while both ends thereof are regulated by the sheet feed regulating plate 21. Further, the abutting surface of the side edge abutting member 32 on the discharge sheet tray 2A is adjusted to a position slightly outside the left end of the discharged sheet S in FIG. 3, and the guide member 33 is shown in FIG. Adjust to a position slightly inward from the right edge of.

When an operator instructs reading of an image from a computer (not shown) connected to the image reading apparatus, the uppermost sheet S from the sheet bundle placed on the sheet placing table 2B is moved into the apparatus by the pickup roller 11. To feed. Here, when a plurality of documents are picked up, they are separated by the feeding roller 12 and the separation roller 13 and fed one by one. The fed sheet is read by the reading sensor pair 15 while being conveyed to the discharge portion by the conveying roller pair 14, and then discharged to the discharged sheet tray 2 </ b> A by the discharge roller pair 16.

While being discharged, the vicinity of one end of the sheet S comes into contact with the guide member 33, proceeds in the discharge direction, and pushes up the lower right end in FIG. 3 following the inclination of the guide member 33. This is because the upper end portion of the guide member 33 is inclined with respect to the installation surface of the apparatus so that the downstream side in the sheet discharge direction is higher. When the sheet S is separated from the paper discharge roller pair 16 and is in a stagnant state, the sheet S rotates so that the left side as viewed from the discharge sheet tray 2A side is lowered, and the pair of the lower right end portions in FIG. The upper left end of the sheet S in FIG. 3 at the corner is pushed down.

The height of the lowermost portion (for example, the upstream end or the vicinity thereof) of the upper end portion of the guide member 33 having such a function as viewed from the surface of the desk or the like on which the apparatus is installed is determined by the sheet S to be discharged next. The height of the sheet discharged from the sheet discharge unit is set to be lower so as not to collide with the rear end of the preceding sheet S. Therefore, even if the apparatus feeds the sheet at a high speed, the alignment is not disturbed. In order to further improve the alignment, it is preferable that the height of the lowest portion of the upper end portion of the guide member 33 when viewed from the surface of the discharged sheet tray is higher than the thickness of the sheet bundle having the maximum stacking amount. .

The sheet S discharged at a speed equal to the peripheral speed of the pair of paper discharge rollers 16 is decelerated due to friction caused by contact with the guide member 33 and stops on the discharge sheet tray 2A while stopping. After that, the sheet S partially on the guide member 33 slides on the inclined sheet stacking surface of the discharge sheet tray 2A toward the left rear direction, that is, the direction indicated by the arrow in FIG. And abut against the rear end abutting surface 31 of the sheet discharge tray 2A and stop.

As described above, by adopting the sheet stacking surface and the shape of the guide member that are the features of the present invention, the apparatus is not complicated and the cost is increased, and the type of sheet to be fed is further increased. Further, even when the apparatus is used in an apparatus that speeds up conveyance and paper discharge, it is possible to provide a discharge sheet tray that can arrange the discharge sheets in an orderly manner.

1 is an external perspective view showing a configuration of an image reading apparatus according to an embodiment of the present invention. Cross section of image reader Top view for explaining a state where the sheet is discharged Left side view of image reader Front view of image reader Right side view of image reader

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Pickup roller 12 Feeding roller 13 Separation roller 14 Conveying roller pair 15 Reading sensor pair 16 Paper discharge roller pair 21 Paper feed regulating plate 2A Paper discharge tray 2B Sheet placing table S Sheet 31 Rear end abutting surface 32 Side end abutting member 33 Guide member 34 Discharge port

Claims (3)

A feeding section for feeding sheets one by one;
A discharge unit for discharging the sheet;
In a sheet feeding apparatus having a discharge sheet tray for stacking and holding sheets discharged from the discharge unit,
The discharge sheet tray is
A rear end abutting surface which becomes an abutting of the rear end of the sheet on the upstream side in the sheet discharging direction;
A guide member that lifts only one of the corners on the downstream side in the discharge direction of the discharged sheet with respect to the sheet stacking surface of the discharge sheet tray;
On the side opposite to the side where the guide member is disposed,
A side end abutting surface that abuts the side end surface of the discharged sheet;
The guide member is capable of moving in a direction substantially perpendicular to the sheet discharge direction, and has a shape in which an upper end portion is inclined so as to be higher on the downstream side in the sheet discharge direction. apparatus. 2. The sheet feeding apparatus according to claim 1, wherein the height of the lowest portion of the upper end portion of the guide member when viewed from the sheet stacking surface is higher than the stacking height of the sheet bundle having the maximum stacking amount. . The sheet stacking surface is
Inclined so that the downstream side is higher than the sheet discharge direction,
3. The sheet feeding apparatus according to claim 1, wherein the sheet feeding apparatus is inclined in a sheet width direction orthogonal to the sheet discharge direction.

Images