JPH03211134A - Paper feeding mechanism - Google Patents

Abstract

PURPOSE:To return a sheet into a sheet tray by simple mechanism by pressing the sheet to a paper feed belt after the termination of paper feeding action, and rotating paper feed rollers reversely to the direction at the paper feeding time. CONSTITUTION:At the time of paper feeding, only the uppermost sheet, that is, only the first sheet 2a is fed, and the second sheet 2b, one sheet below, is positioned, with its front end slightly jutting out from the front end of a sheet tray 1, into the vicinity of a separating roller 11, that is, the second sheet 2b is positioned, on the whole, across the inside and outside of the sheet tray 1. After the termination of paper feeding action, the sheet 2b is pressed to a paper feed belt 3, and paper feed rollers 8, 9 are rotated in the reverse direction IT to the direction at the paper feeding time. The second sheet 2b with its front end jutting out from the sheet tray 1 can be thereby separated from the first sheet 2a and returned positively into the sheet tray 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper feeding mechanism, particularly to a paper feeding mechanism suitable for printers, copying machines, etc.

[Summary of the invention]

In the paper feeding mechanism, the paper is brought into pressure contact with the paper feeding belt after the paper feeding operation is completed, and the paper feeding roller is rotated in the opposite direction to that during paper feeding, so that the paper can be fed into the paper tray with a simple mechanism. This allows for cost reduction.

[Conventional technology]

An example of a paper feeding mechanism provided in conventional printers, copying machines, etc. is the one shown in Japanese Utility Model Application Publication No. 60-170329.

The above-mentioned paper feeding mechanism includes a paper feeding belt that rotates in the paper feeding direction, for example, clockwise, by a pair of paper feeding rollers, and a paper feeding belt that is arranged below the pair of paper feeding rollers and rotates in the same direction as the paper feeding belt, for example. The separation roller rotates clockwise to feed only the topmost sheet of paper that is in pressure contact with the paper feed belt, that is, the first sheet, and to feed the bottom sheet of paper, that is, the second sheet of paper, as described above. It is separated from the first sheet of paper.

In this case, the front end of the separated second sheet of paper is located near the separation roller, slightly protruding from the front end of the paper tray. Conventionally, this second sheet of paper was pushed back into the paper tray by a member such as a lever.

[Problem to be solved by the invention]

The conventional paper feeding mechanism as described above requires a mechanism for pushing the second sheet of paper back into the paper tray by operating a lever each time paper is fed. For this reason, the mechanism becomes complicated,
There was a problem that the cost would increase.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a paper feeding mechanism that can reliably return paper into a paper tray with a simple mechanism.

[Means to solve the problem]

In this invention, the paper is brought into pressure contact with the paper feed belt after the paper feeding operation is completed, and the paper feed roller is rotated in the opposite direction to that during paper feeding.

[Effect]

During paper feeding, only the top paper, that is, the first paper, is fed, and the bottom paper, that is, the second paper, is fed by the separation roller with its front edge slightly protruding from the front edge of the paper tray. , and the second sheet is located entirely inside and outside the paper tray.

Therefore, after the paper feeding operation is completed, the paper is pressed against the paper feeding belt,
Rotate the paper feed roller in the opposite direction to when feeding paper. This separates the paper from the first one and allows the second paper with the front edge to protrude from the paper tray.
The first sheet of paper can be returned to the paper tray without fail.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In this embodiment, a paper feeding mechanism provided in a thermal dye sublimation printer is explained as an example.

FIG. 1 is a diagram showing a paper feeding mechanism.

A large number of sheets of paper 2 are stored in the paper tray 1.

Paper 2 is placed on this paper tray l, and paper 2 is loaded when feeding paper.
A mounting plate 4 is attached to press the paper evenly against the paper feed belt 3. Further, an opening 7 is formed in the front end 5 of the paper tray 1 so that a lift arm 6, which will be described later, can enter the paper tray 1. Note that the paper 2 mentioned above is photographic paper in this embodiment, and the surface of the paper 2 has the following:
A still image is printed by sequentially pressing ink ribbons having primary color pigments of yellow Y1 magenta M1 cyan Cv.

A pair of paper feed rollers 8.9 are disposed above the frame 10 at the front end 5 of the paper tray 1, and are driven by a drive mechanism (not shown) clockwise [direction indicated by arrow T in FIG. 1] and counterclockwise [direction indicated by arrow T in FIG. It is rotatable in both directions (in the direction indicated by the arrow IT in Figure 1) and is pivotally supported. A paper feed belt 3 is wound around this pair of paper feed rollers 8.9.

Below the paper feed roller 8, the frame 10 at the front end 5 of the paper tray 1
A separation roller 11, which is rotatable by a drive mechanism (not shown), is arranged near the separation roller 11. This separation roller 11 is rotatably attached to a support plate 13 via a shaft 12. The support plate 13 is attached to a shaft 14 so as to be rotatable in the downward direction indicated by the arrow and in the direction indicated by the IT force in FIG.

A lift arm 6 is provided below the paper tray 1 at a position corresponding to the opening 7 of the paper tray 1. The lift arm 6 is rotatable in the IT force direction as indicated by the arrow in FIG. 1 by a drive mechanism (not shown). Note that 17 is an axis.

A paper guide 18 is provided above the support plate 13 and the separation roller 11. This paper guide 18 guides the paper 2 taken out one by one from the paper tray 1 to a platen (not shown).

The operation will be explained below with reference to FIGS. 1 to 4. FIG. 1 is a diagram showing the home position of this paper feeding mechanism.

When a paper feeding instruction is issued, for example, from a system controller (not shown), the drive mechanism is controlled to perform the following operations.

First, as shown in FIG. 2, when the lift arm 6 rotates in the direction of the arrow IT force and passes through the opening 7 of the paper tray 1 and comes into contact with the lower surface 19 of the placement plate 4, the lift arm 6 is further rotated in the direction of the arrow IT force to push the front end 20 of the mounting plate 4 upward.

As a result, the top paper, that is, the first paper 2
a contacts the paper feed belt 3 with a predetermined pressing force. Further, at approximately the same time as the lift arm 6 rotates, the support plate 13 moves toward the direction indicated by the arrow IT.
Rotates in the direction of force.

Next, the pair of paper feed rollers 8.9 rotate clockwise, that is, in the direction of arrow T, so that the paper feed belt 3 rotates in the direction of arrow T. As a result, the first sheet 2a moves from the paper tray 1 to the paper guide 18 side. At this time, due to friction between the sheets, for example, two sheets of paper 2a
, 2b may move from the paper tray 1 to the paper guide 18 side, but the separation roller 11 is in contact with the bottom side of this second sheet 2b, and it rotates in the same rotation direction as the paper feed belt 3. , that is, since it is rotating in the direction of arrow T, 2
The first sheet of paper 2b is separated from the first sheet of paper 2a.

After this, as shown in FIG. 3, the paper feed roller 8.9 and separation roller 11 are stopped. Further, since the lift arm 6 rotates in the direction of arrow T and stops, the placing plate 4 and the paper 2 move downward within the paper tray 1. This prevents the paper tray 1 from being pulled out during printing.

Further, as the support plate 13 rotates in the direction of the arrow T, the separation roller 11 also moves downward. Therefore, as shown in FIG. 3, the first sheet of paper 2a is guided to the platen by the paper guide. This first sheet of paper 2a is then wound around a platen (not shown) and pressed against the aforementioned ink ribbon. When this printing operation is completed, the first sheet 2a is ejected. At this point, the front edge 21 of the second sheet 2b is placed in the frame 1 of the paper tray 1.
The paper 2b is located near the separation roller 11 with a slight protrusion toward the paper guide 18 side, and the paper 2b is generally located across the front and rear sides of the frame 10 of the paper tray l.

Therefore, after the paper discharge is completed, an operation is performed to return the second sheet 2b into the paper tray 1.

As shown in FIG. 4, the lift arm 6 rotates again in the direction of the arrow IT force, whereby the paper 2b comes into contact with the paper feed belt 3. Further, substantially simultaneously with the rotation of the lift arm 6, the support plate 13 rotates in the direction of the arrow IT force and comes into contact with the paper feed belt 3.

Next, the pair of paper feed rollers 8.9 rotate in the counterclockwise direction opposite to the direction in which the paper is fed, that is, in the direction of the arrow IT force, and the paper feed belt 3
rotates in the direction of the IT force indicated by the arrow. As a result, the aforementioned paper 2b is transferred from the frame 10 side of the front end 5 of the paper tray 1 to the loading plate 4.
Move to the upper paper 2 side.

As a result, at the end of the paper feeding operation, the front end 21 is located near the separation roller 11 in a state where it slightly protrudes from the frame 10 of the paper tray 1 toward the paper guide 18, and as a whole, the front end 21 is located near the separation roller 11. The paper 2b located both at the front and the rear is reliably returned to the paper tray 1 side.

When the operation of returning the paper 2b to the paper tray 1 is completed, the paper feeding mechanism returns to the home position shown in FIG.

In this way, the paper 2b can be returned into the paper tray 1 with a simple mechanism, making it possible to reduce costs.

This embodiment is applicable not only to thermal dye sublimation printers but also to paper feeding mechanisms that are installed in various printers or copying machines and automatically feed paper.

Furthermore, although this embodiment explains that the operation is controlled by the system controller, the same function is not limited to this, and the same function can be achieved by a mechanical configuration or an electronic circuit configuration. You may.

〔Effect of the invention〕

According to this invention, after the paper feeding operation is completed, the paper is pressed against the paper feeding belt, and the paper feeding roller is rotated in the opposite direction to that during paper feeding, so that the paper can be returned to the paper tray with a simple mechanism. It has the effect of being able to. Furthermore, since the mechanism can be simplified, it is possible to reduce costs.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing one embodiment of the present invention, and FIGS. 2 to 4 are schematic sectional views each illustrating the operation of the paper feeding mechanism. 0 Explanation of main symbols in the drawings 2.2a, 2b: Paper, 3: Paper feed belt, 6: Lift arm, 8.9: Paper feed roller, 11: Separation roller, T2 clockwise, ■T2 counterclockwise direction.

Claims (1)

[Claims] A paper feeding mechanism that presses the paper against a paper feeding belt after the paper feeding operation is completed, and rotates the paper feeding roller in the opposite direction to that during paper feeding.