JP3202872B2 - Paper feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder, and more particularly, to a paper feeder.
A plurality of sheets are stacked and stored, and the sheets are
The present invention relates to a sheet feeding device for taking out sheets one by one and sending them to a predetermined printing position.

[0002]

2. Description of the Related Art Conventionally, for example, in various printers such as a laser printer, a copying apparatus, an offset printing apparatus, and the like, a plurality of sheets are stacked and stored, and the sheets are taken out one by one from an upper part and a predetermined number is taken out. Paper feeders for supplying printing and copying positions are often used.

FIGS. 3 and 4 show such a conventional paper feeder, in which a top surface is opened and a predetermined paper 1 is placed inside.
A box-shaped main body 2 for stacking and storing the paper 1 is provided. Inside the main body 2, a flat paper tray 3 on which the paper 1 is placed is provided. This paper tray 3
The support pin 4 attached to the base end of the main body 2
Are rotatably supported on both side surfaces of the support pin 4 so as to be vertically swingable about the support pin 4.
A pressing spring (not shown) that constantly urges the paper tray 3 upward is disposed on the lower surface side of the paper tray 3.

Separating claws 5 are provided at both ends of the main body 2 at both ends of the paper 1 at predetermined heights to be fixed to both uppermost corners of the paper 1. In the vicinity of the separation claw 5, a paper feed roller 6 is rotatably disposed.

In such a conventional sheet feeding device, predetermined sheets of paper 1 are stacked and placed on the upper surface of the sheet tray 3, and the top corner of the uppermost sheet 1 is placed under the lower surface of the separation claw 5. The paper 1 is stored inside the main body 2 by being locked to the side.

As shown in FIG. 4, the uppermost sheet 1 is pressed below the sheet feeding roller 6 by the urging force of the sheet tray 3 upward, and in this state, the sheet feeding roller 6 is pressed. When driven to rotate, the upper sheet 1 is conveyed by the frictional force between the paper feed roller 6 and the sheet 1, but only the uppermost sheet 1 of the conveyed sheet 1 is separated by the separation claw 5. The sheet 1 is separated from the sheet 1 below, passes over the separation claw 5 and is sent out of the main body 2 to the outside, and the sheet 1 is conveyed to a predetermined printing position.

When the remaining amount of the paper 1 decreases, the paper tray 3 is swung upward about the support pin 4 by the urging force of the paper tray 3 upward. As shown in FIG. 3, always the topmost sheet 1
Is pressed against the paper feed roller 6.

[0008]

However, in such a conventional paper feeder, for example, as shown in FIG.
The tilt angle of the paper tray 3 is different between a state where a large number of sheets 1 of about 100 sheets are stored in the main body 2 and a state where several sheets 1 are stored in the main body 2 as shown in FIG. Since the position of the separation claw 5 is constant,
Depending on the number of sheets 1 stored, the uppermost sheet 1 and the separation claw 5
When the locking height between the uppermost sheet 1 and the separation claw 5 becomes improper, the sheet 1 can be properly sent out. There is a problem that the paper is lost or the proper separation by the separation claw 5 cannot be performed, and a plurality of sheets of paper 1 are sent out, resulting in a feeding failure. This is particularly noticeable when a relatively thick sheet 1 having a thickness of about 0.2 mm is fed, for example.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and enables the separation claw to be always held at an appropriate locking height regardless of the number of sheets stored, even if the sheet is relatively thick. It is an object of the present invention to provide a sheet feeding device capable of reliably sending out sheets one by one.

[0010]

According to the present invention, there is provided a sheet feeding apparatus including a sheet tray for stacking and stacking predetermined sheets inside a main body having an open upper surface. disposed swingably vertically around the proximal end portion, said at a predetermined height to the top of the paper at the tip portion of the body disposed a separation claw to be locked, there above said body The uppermost sheet of paper near the separation claw so as to ride over the separation claw.
In the paper feeder having a paper feed roller that is rotatably arranged to send out the paper, the separation claw is moved between the uppermost sheet and the separation claw according to the swing position of the paper tray according to the amount of stacked paper. It is characterized in that it is formed so as to be operable so that the stop height is within a predetermined range.

Preferably, a claw support plate having a guide hole extending linearly in the up-down direction is provided inside the main body so as to be rotatable up and down around a rear end thereof. The separation claw is formed at an upper end portion of a support plate, and a guide pin protruding to a side of a leading end portion of the paper tray is engaged with the guide hole.

[0012]

According to the paper feeding device according to the present invention, the separation pawl, contracture to swing position by the amount of lamination of the sheets of the paper tray
Are those Warazu locking height between the top of the paper and the separation claw is operated so as to be constant, for example, when the remaining amount of sheets on the sheet tray is reduced, the paper tray is swung upward By the swinging operation of the paper tray, the guide pin of the paper tray moves in an arc shape, whereby the guide hole follows the guide pin, whereby the claw support plate is rotated. By the rotation of the claw support plate,
The locking height between the separation claw and the uppermost sheet can always be maintained at a constant height.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 show an embodiment of a sheet feeding device according to the present invention, in which a predetermined sheet 1 is stacked and placed inside a box-shaped main body 2 having an open top. A flat paper tray 3 for placing the paper tray 3 is provided. The paper tray 3 is urged upward by a pressing spring (not shown), and a support pin 4 attached to a base end thereof is connected to the main body. By being rotatably supported on both side surfaces of the support pin 2, it is arranged so as to be able to swing up and down around the support pin 4.

In this embodiment, a claw support plate 7 formed substantially in an L shape along the front and lower surfaces of the main body 2 is provided on both front sides of the main body 2 up and down around its rear end. The pawl support plate 7 is rotatably disposed on the
Separating claws 5 to be engaged with both uppermost corners of the paper 1 are provided at the upper end of the paper 1. The claw support plate 7 is formed with a guide hole 8 that extends linearly in the up-down direction. The guide hole 8 has guide pins 9 protruding from both sides of the leading end of the paper tray 3. Are engaged. The guide pins 9 of the paper tray 3 are moved in accordance with the vertical swinging operation of the paper tray 3.
The claw support plate 7 is rotated along the guide hole 8. In the above embodiment, the separation claws 5 are provided on both sides of the main body 2, however, they may be formed only on one side of the main body 2.

Further, a paper feed roller 6 is rotatably disposed above the main body 2 and near the separation claw 5.

Next, the operation of the present embodiment will be described.

In this embodiment, predetermined sheets of paper 1 are stacked and placed on the upper surface of the sheet tray 3, and the top corners of the uppermost sheet 1 are engaged with the lower surface of the separation claw 5. Thus, the paper 1 is stored inside the main body 2. In this case, in the present embodiment, the paper tray 3 is inclined downward about the support pin 4 due to the lamination thickness of the paper 1, and the guide pin 9 of the paper tray 3 is The claw support plate 7 is rotated clockwise in FIG. 2 so that the locking height between the separation claw 5 and the uppermost sheet 1 is set to a predetermined value. Is held at the height. The locking height between the separation claw 5 and the uppermost sheet 1 is, for example, 0.
In the case of about 2 mm, 0.5 to 2.0 mm is appropriate.

When the uppermost sheet 1 is pressed under the sheet feed roller 6 by the urging force of the sheet tray 3 upward, the sheet feed roller 6 is driven to rotate.
The upper sheet 1 is conveyed by the frictional force between the paper feed roller 6 and the sheet 1, but only the uppermost sheet 1 of the conveyed sheet 1 is separated from the lower sheet 1 by the separation claw 5. The paper 1 is separated and gets over the separation claw 5 and is sent out of the main body 2 to convey the paper 1 to a predetermined printing position.

When the remaining amount of the paper 1 is reduced as a result of the paper feeding being performed as described above, the paper tray 3 is swung upward about the support pin 4 by the urging force of the paper tray 3 upward. So that, as shown in FIG.
The uppermost sheet 1 is always pressed against the sheet feed roller 6. In this case, in the present embodiment, when the paper tray 3 is swung upward, the guide pins 9 of the paper tray 3 move in an arc around the support pins 4. Since the guide hole 8 of the plate 7 is formed in a straight line, the upward movement of the paper tray 3 causes the claw support plate 7 to rotate counterclockwise in the drawing. By the rotation of the claw support plate 7, the locking height between the separation claw 5 and the uppermost sheet 1 is reduced, for example, as shown in FIG. Even if it does, it will always be kept at a certain height.

Therefore, in this embodiment, the locking height between the separation claw 5 and the uppermost sheet 1 is increased by rotating the claw support plate 7 in response to the swing of the sheet tray 3. ,
Since the sheet can always be held at a constant height, the separation effect of the separation claw 5 can be kept constant regardless of the remaining amount of the sheet 1, and as a result, the sheet 1 stacked on the sheet tray 3 can be maintained. Can be reliably sent out one sheet at a time, and it is possible to reliably prevent the sheet 1 from not being sent out or a plurality of sheets 1 being sent out.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed.

[0023]

Sheet feeding apparatus according to the present invention as described above, according to the present invention is maintained, the locking height of the separation claw and the top of the sheet regardless of the oscillation of the paper tray, always at a constant height Therefore, the separation effect of the separation claw can be kept constant irrespective of the remaining amount of paper, and as a result, the paper stacked on the paper tray can be reliably sent out one by one. There are effects such as the fact that the occurrence of a paper feeding failure in which the paper is not sent out or a plurality of sheets are sent out can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a sheet feeding apparatus according to an embodiment of the present invention in a state where several sheets are stacked.

FIG. 2 is a schematic configuration diagram of a sheet feeding device of the present invention in a state where a large amount of sheets are stacked.

FIG. 3 is a schematic configuration diagram showing a state in which several sheets are stacked in a conventional sheet feeding device.

FIG. 4 is a schematic configuration diagram showing a state in which a large number of sheets are stacked in a conventional sheet feeding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper 2 Main body 3 Paper tray 4 Support pin 5 Separation claw 6 Paper feed roller 7 Claw support plate 8 Guide hole 9 Guide pin

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B65H 1/00-3/68

Claims (2)

(57) [Claims] 1. A paper tray for stacking and stacking predetermined papers is disposed inside a main body having an open upper surface so as to be swingable up and down around a base end thereof. A separation claw is provided at a leading end of the top sheet to be locked at a predetermined height to the top sheet, and the top sheet is sent over the separation claw above the main body and near the separation claw. Sa
In the sheet feeding device having a sheet feeding roller to be rotatably disposed, the separation claw is provided with a locking height between the uppermost sheet and the separation claw irrespective of a swing position due to a stack amount of sheets in the sheet tray. A sheet feeding device characterized in that the sheet feeding device is formed so as to be operable so as to be constant . 2. A claw support plate having a guide hole extending linearly in the up-down direction is provided inside the main body so as to be rotatable up and down around a rear end thereof. 2. The paper feeding device according to claim 1, wherein the separation claw is formed at an upper end portion, and a guide pin protruding from a front end portion of the paper tray is engaged with the guide hole.