JP4246135B2 - Paper feed tray and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet material supply apparatus used for an image forming apparatus such as a copying machine, a printer, a facsimile machine, a printing machine, or a complex machine thereof.

In general, a sheet material supply apparatus is configured such that a sheet material is stacked on a bottom plate that can be rotated or a bottom plate that can be moved up and down. The sheet material is fed one by one from the uppermost sheet material by the conveying force and conveyed from the sheet feed tray to the image forming apparatus.
In such a paper feed tray, bag-shaped sheet materials such as envelopes and medicine bags are stacked, and this bag-shaped sheet material may be fed one by one to form an image in the image forming unit.・ Sheet materials such as medicine bags have a bag shape with the bottom part glued, and the bottom part of the glued bag has a different thickness from the entrance part that is not glued. It becomes a sheet material block with different height. If the heights of the stacked sheet material blocks are not uniform on the left and right sides in the conveyance direction, the conveyance load applied to the sheet material is biased, resulting in paper feed defects such as skew, folds, and unfeeds. .
Conventionally, as shown in Patent Documents 1 and 2, the height of the block is reduced by limiting the sheet stacking amount by limiting the sheet stacking amount to a small amount, or by limiting the stacking direction of the sheet material. As a measure to prevent the above-mentioned problems, it has been ensured that there is no bias on the left and right with respect to the conveyance direction.
Japanese Patent Laid-Open No. 9-175777 JP-A-5-229699

However, in the conventional technology, there is a problem that the usage of the user is limited, and the number of times the sheet material is replenished is increased, so that convenience is reduced, and the sheet conveyance time per sheet is increased. There was a problem that productivity of image formation was lowered.
The present invention has been made in consideration of the above-described circumstances, and enables a bag-like sheet material such as an envelope and a medicine bag to be smoothly conveyed into an image forming apparatus, and the height difference of the stacked sheet material blocks. It is an object of the present invention to provide a sheet material supply device that can prevent the occurrence of paper feed defects such as skew, bent ears, and non-feed due to the above.

In order to solve the above-described problem, the invention according to claim 1 is a pair of sheets that are arranged on the left and right sides in the sheet material conveyance direction and are movable in the width direction of the sheet material according to the size of the sheet material. and side fences have lacked the side fences enters cut on the left and right sides of the conveying direction of the sheet material, and vertically movable bottom plate for laminating the sheet material, the sheet feed tray having a provided on the bottom plate Further, a bottom raising member is provided on either the left or right side in the conveying direction of the sheet material on the downstream side of the notch .
A second aspect of the present invention is the paper feed tray according to the first aspect, wherein the height of the bottom raising member is adjustable.
A third aspect of the present invention is the paper feed tray according to the first aspect , wherein the bottom raising member is configured to be detachable from the bottom plate.
A fourth aspect of the present invention, the most important feature image forming apparatus having a paper feed tray of claims 1 to 3 any one SL placement.

According to the sheet feeding tray of the present invention, the bottom raising member is provided on either the left or right side in the sheet conveyance direction on the downstream side of the notch provided in the bottom plate, so that the height of the sheet material on the left and right with respect to the conveyance direction during stacking is increased. This eliminates the difference in height of different sheet materials and prevents paper feeding problems such as skew and non-feeding due to differences in the left and right transport loads when transported from the paper feed tray to the image forming unit. it can.
According to the paper feed tray of the present invention, by making the bottom raising member movable in the height direction, it is possible to obtain an optimum bottom raising height according to the type and size of the sheet material to be stacked. It is possible to prevent paper feeding problems such as skew and non-feed due to load deviation at the time.
According to the paper feed tray of the present invention, the bottom raising member is detachable from the bottom plate body, so that it is possible to obtain an optimum bottom raising height according to the type and size of the sheet material to be stacked. In addition, it is possible to prevent paper feeding problems such as skew and non-feed due to load deviation during conveyance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view of a paper feed tray according to the present invention. A paper feed tray 1 according to this embodiment as shown in FIG. 1 is an image forming apparatus (reading optical system, writing optical system) such as a copying machine, a FAX, or a printer. The sheet material P is attached to a sheet feeding unit of an image forming unit, a sheet feeding unit, a sheet discharge unit, and the like, and stacks and accommodates sheet materials P fed toward a transfer position provided in the image forming unit. The paper feed tray 1 includes a pair of side fences 3 that are located on both sides in the width direction of the sheet material P to be accommodated and are movable in the width direction of the sheet material P according to the size of the sheet material P, and a rear end portion in the paper feed direction And an end fence 4 that presses the end face of the sheet material in the conveying direction, and a bottom plate 2 that pushes up and holds the sheet material P to a feed position where the sheet material P can be fed out.
FIG. 2 is a schematic diagram of the bottom plate and the bottom plate raising mechanism, and shows a drive mechanism that turns the bottom plate up and down. The drive mechanism includes a motor provided in the main body of the image forming apparatus, a drive shaft connected to the motor, and a rotating arm 5 that is integrally attached to the end of the drive shaft and disposed at the bottom of the bottom plate. Has been. In this configuration, when the paper feed tray is set in the main body of the image forming apparatus, the motor is driven, and the drive shaft rotates accordingly, and the rotating arm 5 that rotates integrally with the drive shaft rotates. The push-up piece 5a provided on the turning arm 5 pushes up the bottom plate 2 to cause the bottom plate to turn up around the turning fulcrum 2a. Along with this operation, the sheet material P placed on the bottom plate is pushed up to a feed position where it can be fed out and held (standby).
FIG. 3 is a side view of the sheet material separating mechanism, showing a sheet feeding mechanism that separates and feeds the stacked sheet materials P one by one. This paper feeding mechanism is composed of a calling roller (pickup roller) 6 that is in contact with the uppermost surface of the transfer paper P by raising the bottom plate, a paper feeding roller (feed roller) 7 and a reverse roller (reverse roller) 8 that face each other. It is configured. When a print command is input to the image forming apparatus by an operation from the operation unit or a signal from the host machine, the paper feeding roller 7 and the calling roller 6 are rotationally driven by the paper feeding signal. The reversing roller 8 is driven to rotate in the counter-feeding direction via a torque limiter. The uppermost sheet material P is fed out by the rotation of the calling roller 6 in contact with the sheet material P, and is fed into the nip portion between the sheet feeding roller 7 and the reverse rotation roller 8. When only one sheet material is fed into the nip portion, the reverse roller torque limiter does not interfere with the conveyance of the sheet material P conveyed by the sliding paper feeding roller, and the sheet material P remains as it is. It is conveyed in. When two or more of the transferred transfer sheets are overlapped and fed into the nip part, the torque limiter of the reverse roller does not slip and the roller rotates in the reverse direction. The other sheet material is conveyed in the reverse direction, and only one sheet material is conveyed into the image forming apparatus main body.

FIG. 4 is a schematic view of a bottom plate provided with a height difference. The tray bottom board which provided the height difference in right and left with respect to the conveyance direction is shown. The tray bottom plate has a structure in which a height difference of several millimeters is provided by raising a part 2A on either the left or right side (in the drawing, the back side of the tray) of the tray with respect to the conveyance direction. This makes it possible to reduce the conveyance load deviation in the sheet material conveyance process even when the stacked sheet material blocks have a difference in height from left to right with respect to the conveyance direction. That is, if the left or right side of the sheet material bundle is set lower on the higher portion 2A, the height difference can be reduced.
According to this, by raising a part or the entire surface of either one of the left and right bottom plates with respect to the conveyance direction to provide a height difference, the height of the sheet material having a different height on the left and right with respect to the conveyance direction when stacked. When the difference is canceled and the sheet is transported from the sheet feed tray to the image forming unit, it is possible to prevent a sheet feeding failure such as skew or non-feed due to a difference in the left and right transport load.
FIG. 5 is a schematic view of a bottom plate provided with a height difference movable in the height direction. Several portions 2 </ b> C that are moved up and down by the screw mechanism 9 are provided on either the left or right of the conveying direction on the bottom plate. Accordingly, it is possible to set an optimum height difference according to the sheet material to be used.
According to this, it is possible to obtain the optimum height for raising according to the type and size of the sheet material to be loaded by making the structure where the bottom is raised movable in the height direction, and the load deviation during conveyance It is possible to prevent paper feed defects such as skew and non-feed due to the paper.
FIG. 6 is a view showing a bottom plate provided with a detachable height difference. A plate-like bottom raising member 10 having a height of several mm is bonded on the bottom plate with a seal or the like. Since the bottom raising member 10 can be replaced, it is possible to set the optimum height difference according to the sheet material to be used.
According to this paper feed tray, it is possible to obtain the optimum bottom height according to the type and size of the sheet material to be stacked by making the bottom raised portion detachable from the bottom plate body, It is possible to prevent paper feeding problems such as skew and non-feed due to load deviation during conveyance.

1 is a schematic view of a paper feed tray according to the present invention. Schematic of a bottom plate and a bottom plate raising mechanism. The side view of a sheet material separation mechanism. Schematic of the baseplate which provided the elevation difference. Schematic of the baseplate which provided the height difference movable in a height direction. Schematic of the baseplate which provided the height difference which can be attached or detached.

Explanation of symbols

P sheet material 1 sheet feeding tray body 2 bottom plate 3 front side fence 4 rear side fence 5 rotating arm 6 calling roller 7 sheet feeding roller 8 reverse roller 9 screw type bottom raising member 10 detachable bottom raising member

Claims (4)

A pair of side fences that are arranged on the left and right sides of the sheet material in the conveyance direction and are movable in the width direction of the sheet material according to the size of the sheet material, and the side fences on the left and right sides in the conveyance direction of the sheet material has a notch enters a vertically movable bottom plate for laminating the sheet material, the sheet feed tray having a
A sheet feed tray, wherein a bottom raising member is provided on either the left or right side of the sheet material in the conveyance direction downstream of the notch provided on the bottom plate . 2. The paper feed tray according to claim 1, wherein a height of the bottom raising member is adjustable. 2. The paper feed tray according to claim 1 , wherein the bottom raising member is configured to be detachable from the bottom plate. An image forming apparatus comprising the paper feed tray of claims 1 to 3 any one SL placement.

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