JPH05213460A - Paper sheet carrying mechanism - Google Patents

Abstract

PURPOSE:To reduce the restriction both in the length required for providing a belt with a necessary frictional force for feeding paper sheets and in the material by fitting a timing belt to a pulley that has been fitted to a driving shaft, and by pressing the timing belt against the paper sheets from the above of the timing belt. CONSTITUTION:An elastic projected piece is provided to a part of a frame 8 for covering a timing belt 7 so as to be extended rearwards, and a rotary roller 9 rotatably fitted to the projected piece with a proper torque presses the timing belt 7 with the elasticity of the projected piece. A pad-holder 3 is bridged between a tray 1 and a pulley 6 so as to have a slope, and the pad- holder 3 is energized by a spring, so that the pad 4 that has been fixed to a turning part is pressed by the pulley 6 via the timing belt 7. The timing belt 7 presses paper sheets 2 by the pressing force both of the weight of the nonengaging part itself and of the rotary roller 9, and the paper sheets 2 are carried to a nip point by the rotation of the timing belt 7, and they are separated and fed one by one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying mechanism of a sheet feeding device.

[0002]

2. Description of the Related Art In a conventional sheet conveying mechanism, a belt having a sufficient length is engaged with the uppermost portion of a sheet by its own weight so that a frictional force between the sheet and the belt is relatively small. Even if the stacking height is changed according to the feeding of the paper, it is adapted to engage with it (for example, Japanese Patent Publication No. 2-4056).
(See Japanese Patent Publication No. 5).

[0003]

However, in such a sheet conveying mechanism, the length of the belt affects the weight of the unsupported portion, and the frictional force acting on the sheet is proportional to the pressure of the belt. Since the pressure is equal to the weight of the unsupported portion of the belt, the belt was limited in length and material to provide the frictional force needed to feed the paper.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a paper transport mechanism in which the length and the material are less restricted because the belt gives a frictional force necessary for feeding the paper.

[0005]

In order to achieve the above object, in a sheet conveying mechanism of the present invention, a timing belt for conveying a sheet to a nip point, and a drive shaft for rotating a pulley for rotating the timing belt. , Paper 1
It is characterized by having a separating means for separating the sheets one by one and a means for pressing the timing belt from above the timing belt onto the paper.

Further, the separating means for separating the sheets one by one is characterized by being a timing belt and a pad, or a timing belt and a separating roller.

The means for pressing the timing belt against the paper from above the timing belt is a frame pivotally supported by a drive shaft, and a rotating roller attached to the frame pivotally supported by the drive shaft is used.

[0008]

In the sheet conveying mechanism constructed as described above, the pressure for pressing the timing belt against the sheet is obtained by the weight of the timing belt and the means for pressing the timing belt against the sheet from above.

[0009]

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

FIG. 1 is a side view of a paper feed device adopting a friction pad system showing an embodiment of the present invention.

Sheets 2 are stacked on the tray 1.
A drive shaft 5 that is separated from the sheet 2 and rotates by receiving a drive force from a power source (not shown) is attached. Drive shaft 5
The toothed pulley 6 is fixed to the. Pulley 6
The timing belt 7 is attached to the top. The timing belt 7 is longer than the outer circumference of the pulley 6, and the non-meshing portion that is not meshed with the pulley 6 is in contact with the sheets 2 stacked backward.

A frame 8 is rotatably supported on the drive shaft 5 and attached to an upper portion of a pulley 6. Frame 8
Covers the pulley 6 in order to prevent the slack of the timing belt 7 at the portion where the timing belt 7 and the pulley 6 mesh with each other. A projecting piece having a spring property extends rearward at a portion of the frame 8 covering the timing belt 7. A rotary roller 9 is rotatably attached to the projecting piece with an appropriate torque. The rotating roller 9 presses the timing belt 7 by the spring property of the protruding piece.

In front of the tray 1, a pad holder 3 bridges the tray 1 and the pulley 6 at their lower portions with a certain angle with respect to the tray 1. The pad holder 3 is biased by a spring (not shown), and presses the pad 4 fixed to the rotating portion against the pulley 6 via the timing belt 7.

The material of the timing belt 7 is natural rubber,
Conventional rubbers such as neoprene, styrene-butadiene, polyacrylonitrile and isoprene may be used.

The friction coefficient μ of the timing belt 7 with respect to the sheet of paper has a relationship of μ2 <μ1 <μ with the friction coefficient μ1 of the pad 4 with respect to the sheet of paper and the friction coefficient μ2 of the sheet of paper.

Next, paper feeding will be described. The drive shaft 5 is rotated by the driving of the power source, and the pulley 6 and the timing belt 7 are rotated. Since the rotating roller 9 pressing the timing belt 7 has an appropriate torque for rotating, it rotates the frame 8 following the rotation of the timing belt 7. After that, the rotating roller 9 starts rotating and presses the timing belt 7 downward. The timing belt 7 presses the paper by its own weight of the non-meshing portion with the pulley 6 and the pressing of the rotating roller 9. Paper 2
Are conveyed to the nip point between the pad 4 and the timing belt 7 by the rotation of the timing belt 7, and are separated and delivered one by one.

FIG. 2 is a side view of a sheet feeding device when a friction roller system is adopted in another embodiment of the present invention.

Between the tray 1 and the pulley 6, an inclined plate 10 having a certain angle to the sheet 2 and a timing belt 7 are pressed by a spring (not shown) in a direction perpendicular to the sheet 2. There is a separating roller 11.

Although the separation method is different, the operation of conveying the paper to the nip point is the same as that in FIG.

In the above embodiment, the paper conveying mechanism using the rotating roller 9 as the means for pressing the timing belt 7 from above the timing belt 7 to the paper is described, but the frame directly presses the timing belt 7 to the paper. May be.

Further, the pressure for pressing the timing belt 7 from above the timing belt 7 to the paper is a friction resistance such as a friction force when the frame and the pulley, the timing belt or the drive shaft, and the rotating roller rotate.

[0022]

Since the timing belt has the rotary roller for pressing the paper, the length and material restrictions can be reduced because the belt provides the frictional force necessary for feeding the paper.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a paper transport mechanism according to the present invention.

FIG. 2 is a side sectional view showing another embodiment of the paper transport mechanism.

[Explanation of symbols]

 1 Tray 2 Paper 5 Drive Shaft 6 Pulley 7 Timing Belt 8 Frame 9 Rotating Roller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Imae 347 Hino, Hino-shi, Tokyo Orient Toki Time Co., Ltd. Hino factory (72) Inventor Manabu Hashikake 347 Hino, Hino-shi, Tokyo Orient Time total Hino Co., Ltd. in the factory

Claims (5)

[Claims] 1. A sheet feeding device for separating sheets stacked on a tray, a timing belt for conveying the sheets to a nip point, a pulley for rotating the timing belt, a drive shaft for rotating the pulley, and a sheet. A sheet conveying mechanism comprising: a separating unit that separates the sheets one by one; and a unit that presses the timing belt from above the timing belt onto a sheet. 2. The timing belt and the pad are the separating means for separating the sheets one by one.
The paper transport mechanism described. 3. The sheet conveying mechanism according to claim 1, wherein the separating means for separating the sheets one by one is a timing belt and a separating roller. 4. The paper transport mechanism according to claim 1, wherein the means for pressing the timing belt from above the timing belt to the paper is a frame pivotally supported by a drive shaft. 5. The sheet conveying mechanism according to claim 1, wherein the means for pressing the timing belt from above the timing belt onto the sheet is a rotating roller attached to a frame pivotally supported by a drive shaft.