JPH0141581B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stacking device for a copying machine that stacks sheets discharged on a one-sided basis with the leading edge and one side edge aligned at a predetermined position.

When double-sided copying is performed using a copying machine, the paper that has been copied on one side is re-fed, but this may cause inconveniences such as misalignment between the paper and the photoreceptor in the front, back, left, and right directions. To avoid this, it is necessary to stack the sheets on the tray after single-sided copying and to eject them one by one into the tray with their leading edges and reference side edges perfectly aligned in the predetermined positions. .

Conventionally, for this purpose, a front abutment plate and a reference side wall are provided on the front edge and one side of the tray that receives the paper to be ejected, and the paper is ejected onto the tray. It is known that the paper is conveyed diagonally so that the front edge and reference side edges of the paper follow these reference planes and are aligned. direction is tilted with respect to the transport direction)
If the paper is ejected with the reference side edge shifted outward, the leading edge of the paper may hit the rear end of the reference side wall, causing the paper to rotate or jam.

In view of the above-mentioned problems of the conventional paper alignment and stacking device, the present invention makes it possible to reliably align the ejected paper sheets one by one with a reference wall using a simple mechanism, and when refeeding paper. An object of the present invention is to provide a stacking device for a copying machine that can feed paper at a predetermined paper feeding reference position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a duplex tray of a copying machine (a tray that serves both as a paper ejecting and paper feeding tray used when performing duplex copying) will be described in detail below with reference to the drawings.

The outline of the operations of ejecting paper to the duplex tray, stacking, and refeeding for back-side copying will be explained with reference to FIGS. roller 3
After that, the sheets are reversed, and the sheets are ejected and stacked one by one onto the double-sided tray 5 by the ejection roller 4, regardless of the paper size (B4, A4, B5, etc.), on a one-sided basis. When the paper stack 1' on the duplex tray 5 reaches a predetermined number, the bottom surface of the duplex tray 5 is pushed up by the tray pressure arm 6, as shown in FIG. The paper 1 is pressed with appropriate paper feeding pressure by the separation feed roller 7 which is pivotally supported on the copying machine frame above the front end of the paper 1, and the paper 1 is fed at a predetermined timing by the action of the separation feed roller 7 and the separation roller 8. The paper is re-fed one by one for back-side copying.

In this device, as a stacking device for aligning the sheets 1 ejected to the double-sided tray 5, a front abutment plate 9 serves as a reference surface for aligning the leading edges of the sheets 1, and a side edge of the sheets 1 on the reference side is brought into contact with the stacking device. A reference side wall 10 for aligning the edges and an inclined roller 11 for transporting the sheets discharged into the double-sided tray 5 one by one toward the front contact plate 9 and the reference side wall 10 are provided. Further, the double-sided tray 5 reciprocates laterally by a certain distance "a" along its pivot axis,
Each end position can be maintained.

The front abutment plate 9 is fixed to the copying machine frame in contact with the front end of the duplex tray 5 and perpendicular to the paper ejection direction, and its upper end is placed at an appropriate height so that it can be used when refeeding paper. There is a smooth transition to the guide plate.

The reference side wall 10 is provided on one side of the double-sided tray 5 so as to be perpendicular to the front plate 9 and the bottom plate of the double-sided tray 5 . This reference side wall 10
The installation position is a distance a outside the reference side position of the paper that is normally discharged from the discharge roller 4 when the duplex tray 5 is displaced upward in FIG. 3, and an appropriate position in front of the discharge roller 4. It is provided between the point and a point spaced backward by α from the side of the inclined roller 11, and both ends thereof are bent in an outward diagonal direction.

The inclined roller 11 is provided near a corner of the front end of the double-sided tray 5 on the side where the reference side wall 10 is provided, and is inclined at an angle θ toward the reference side wall 10 with respect to the paper traveling direction. The inclined roller 11 has its drive shaft 12
Inclined roller arm 1 rotatably supported around
A belt 14 is pivotally supported on the free end of the paper tray 5 and is stretched between the belt 14 and the drive shaft 12.
While being discharged, it is continuously driven to rotate in the direction of the arrow shown in FIG. The inclined roller arm 13 is movable between a raised position where the tip is flipped up and a lowered position where the roller 11 at the tip can follow the top surface of the paper due to its own weight. Also, inclined roller 1
1, when the inclined roller arm 13 is in the lowered position, the tray 5 is applied with an appropriate pressing force due to its own weight, as shown in FIG.
By rotating while pressing against the upper surface of the uppermost sheet 1, only the uppermost sheet 1 is conveyed in an oblique direction inclined at an angle θ with respect to the paper ejection direction, and the sheet 1
The feeding force is set so that the front edge of the sheet hits the front abutting plate 9 and the side edge of the sheet hits the reference side wall 10 until it completely follows the sheet, and thereafter the sheet does not slip and jam. This feeding force is determined by the weight of the inclined roller 11 and the material of the inclined roller 11.
This is caused by the frictional force between the circumferential surface of the paper 1 and the paper 1, and by making this frictional force larger than the frictional force between the paper sheets, a new stack of paper sheets that has already been aligned to the standard can be ejected without disturbing it. It is possible to align the printed sheets. According to the experimental results, sponge rubber was the most suitable material for the rollers 11. Note that the contact pressure between the roller 11 and the paper 1 described above is
It is also possible to obtain an appropriate value by means such as a spring or the like, in addition to using the own weight of 1.

The horizontal movement of the duplex tray 5, the raising and lowering of the tray pressurizing arm 6, and the raising and lowering of the inclined roller arm are rotated by a half-rotation clutch that is controlled by selecting the duplex copying mode and turning on and off a solenoid according to a paper refeed command. The cam is sequentially controlled via a link mechanism as described below. That is, when the duplex mode is selected, the tray pressure arm 6 is lowered to release the pressure on the duplex tray 5, and then the duplex tray 5 is moved by a distance "a" to the third
In the figure, the inclined roller arm 13 moves laterally upward and then descends. When a command is given to refeed paper from the duplex tray, the inclined roller arm 13 is first raised, and then the duplex tray 5 is moved laterally by a distance "a" until the reference side wall 10 is in a position matching the paper passing reference. The pressurizing arm 6 then rises to push up the double-sided tray 5 and press the upper surface of the sheet placed thereon against the separating and feeding rollers 7.

Since this device is constructed as described above, the paper 1 is turned upside down by the turn roller 3 and discharged one by one into the double-sided tray 5 from the discharge roller 4.
are sequentially sent toward both the front abutment plate 9 and the reference side wall 10 by the inclined rollers 11, and the front end and reference side edge of the paper abut against both members 9 and 10, respectively, and are completely This ensures that the paper 1 is perfectly aligned in the predetermined position. However, the inclined roller 11
As described above, the feeding force is set to an appropriate strength, so even if the inclined rollers 11 are continuously driven during the paper ejection operation, the paper 1 will not completely contact the front contact plate 9 and the reference side wall 10. After contact, it will slip, so there is no risk of jamming.

The inclined roller 11 is pivotally supported at one end by the free end of an arm that is pivotally supported, and is brought into pressure contact with the upper surface of the paper by its own weight, so that it can easily follow even if the paper is stacked and the thickness changes.

If the paper 1 skews or is conveyed with a misaligned horizontal position in the paper transport path up to the paper ejection roller 4 and enters the duplex tray 5 from the ejection roller 4, if the reference side wall 10 is If the paper is placed at a position that coincides with the reference side surface of the paper discharged from the discharge roller 4, the leading corner of the paper may collide with the edge of the reference side wall 10, causing a jam or causing the paper to Although there is a risk of running over the reference side wall 0, in this device, the position of the reference side wall 10 is set outward by an appropriate amount a from the position of the side edge of the reference side of the paper discharged from the discharge roller 4 in the normal position. Therefore, even if the paper 1 is ejected with some degree of skew or lateral deviation, the above-mentioned accident will not occur.

Furthermore, as shown in FIG. If the corner 1a of the tip of the paper on the reference side wall side reaches the reference surface from an oblique direction, and if there is a reference side wall 10 there, the corner 1a of the paper will bend or go over the reference side wall and be aligned. However, in this device, the reference side wall 10 is not installed between the front abutment plate 9 and the side of the inclined roller to the rear by α, so the paper 1 may skew and advance. come,
Even when it is sent in an oblique direction by the inclined rollers 11,
As shown in FIG. 4, the corner portion 1a of the paper 1 does not collide with the reference side wall 10, and after the front end corner portion 1b on the opposite side abuts against the front contact plate 9, the paper 1 is moved onto the inclined roller 11. It rotates around the corner 1b due to the feeding force and the reaction force acting on the corner 1b, and one corner 1
a moves as shown by continuous arrows in FIG. 4, and the front edge and side edges completely abut against the front abutment plate 9 and the reference side wall 10, respectively, and are aligned at predetermined positions.

When re-feeding the paper stack 1' that has been aligned and stacked in the manner described above, the second
As shown in the figure, the lower surface of the tray 5 is pushed up by the tray pressurizing arm 6 so that the upper surface of the bundle bundle 1' comes into pressure contact with the separating and feeding roller 7. At this time, the inclined roller arm 13 Through a mechanism, the inclined roller 11 rotates counterclockwise in conjunction with the operation of the pressure arm 6, and the inclined roller 11 is displaced to a position away from the upper surface of the paper bundle 1', which is at the position lifted by the pressure arm 6. and retained. Therefore, there is no concern that the inclined rollers 11 will brake the feeding of the paper 1 by the separation feeding rollers 7, resulting in non-feeding, or that a feeding force in an oblique direction will be applied, causing skew.

In this case, before the upper surface of the paper bundle 1' is pressed by the pressure arm 6 against the separating and feeding roller 7, the tray 5 moves in the lateral direction by a distance "a", so that the paper receiving sheet shown in FIG. At times, the paper bundle' aligned along the reference side wall 10, which was located at a position "a" outside the reference position of the ejected paper, moves to the front side of the figure by "a" together with the tray 5 when refeeding the paper. and match the paper feed reference position. Therefore, there is no possibility of horizontal misalignment between the re-fed paper and the image on the photoreceptor.

As described above, according to the present invention, even if the paper is ejected one by one, even if the ejection position of the paper is slightly shifted or the paper is ejected in a skewed manner, the simple mechanism can reliably and perfectly align and stack the sheets. However, it becomes possible to feed paper at the paper feeding reference position when refeeding paper.

[Brief explanation of drawings]

FIG. 1 is a side view showing the state of the embodiment of the present invention during paper stacking, FIG. 2 is a side view showing the state of the same embodiment during paper refeeding, and FIG. 3 is a plan view of the main part thereof. FIG. 4 is a plan view illustrating an example of its operation. 1...Paper, 4...Ejection roller, 5...Tray,
9... Front abutment plate, 10... Reference side wall, 11... Inclined roller.

Claims (1)

[Claims] 1 Paper is discharged onto a tray one by one on a one-sided basis, and the paper is conveyed in an oblique direction, and the leading edge of the paper and one side edge are connected to a front plate provided in front of the tray at right angles to the paper discharge direction. , in a tray stacking device for a copying machine that stacks and refeeds sheets by aligning them at a predetermined position by colliding with the reference side walls provided on one side of the tray parallel to the paper ejection direction, respectively; The reference side wall is formed integrally with the tray, and the tray has a first position where the reference side wall occupies a reference position, and a position where the reference side wall is a predetermined distance outward from the reference position in a direction perpendicular to the paper ejection direction. When sheets are ejected to the tray, aligned and stacked, the tray is held at the second position, and the sheets stacked on the tray are re-fed. A stacking device characterized in that the tray is moved to the first position and held at this position before stacking paper.