JPH02175521A - Paper sheets feeding device - Google Patents

Abstract

PURPOSE:To prevent the reduction in the frictional coefficient of recording paper in a low temperature environment, and the poor paper feeding due to slip accompanied by the increase of curl and the increase in rigidity by providing, on a recording paper pressing plate, a projected member by which the recording paper sheets are pressed against a transfer roller with a given winding angle. CONSTITUTION:In the case of paper feeding, a projected member 17 on a recording paper pressing plate 13 abuts on the lowest part or recording paper sheets 11 to deform the entire recording paper sheets 11 in an upwardly convex shape, and the recording paper sheets 11 are pressedly brought into contact with a transfer roller 12 so as to be wound around it, so that the pressedly contacting area is increased. As a result, a larger transfer force can be obtained, and poor paper feeding can be prevented, and also the load of the entire equipment can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a paper feeding device for an image printer equipped with an automatic paper feeding mechanism.

2. Description of the Related Art In a conventional paper feeding device for an image printer equipped with an automatic paper feeding mechanism, as shown in FIG. At the same time, a recording paper pressing plate 13 is disposed below so as to be rotatable up and down about a rotational shaft. When feeding paper, the recording paper pressing plate 13 is pressed upward by the elevating means 19,
The recording paper 11 stacked in the recording paper cassette 18 is lifted up, and the recording paper 11 is pressed horizontally against the conveyance roller 12, and conveyance is performed by the generated frictional force.

Even if there are multiple sheets of recording paper 11, recording paper 1
The recording paper pressing plate 13 has a shape of a single plate with a bent portion so that the recording paper pressing plate 1 maintains a horizontal state.

The recording paper 11 conveyed to the conveyance roller 12 is one sheet or several sheets of the upper layer, and after being conveyed while being guided by the guide member 14, when passing between the separate roller 15 and the reverse roller 16, Only the top layer is sorted and transported. The separation roller 15 rotates only in the transport direction, and the reverse roller 16 has a slip mechanism, so that when two or more sheets of recording paper 11 enter, it reverses the transport rotation direction and transports all but the top sheet. The paper is pushed back in the opposite direction, and the above pair forms a sorting mechanism to automatically feed only one sheet.

Problems to be Solved by the Invention However, with the above configuration, when feeding special recording paper for image printers in a low-temperature environment, the friction coefficient of the recording paper decreases, the rigidity increases, and the amount of curl increases. Accompanied by
It became difficult to obtain the driving force necessary for conveyance from the conveyance rollers, and the recording paper and the conveyance rollers sometimes slipped, causing paper feeding failures. In addition, in order to prevent paper feeding failures, it is necessary to excessively increase the pressing force of the elevating means that presses the recording paper pressing plate.
This also had the problem of increasing the load on the entire device.

In view of the above-mentioned problems, the present invention has a recording paper press plate that is movable up and down that stacks a plurality of sheets of recording paper, contacts a part of the recording paper surface, and wraps the recording paper around a conveyance roller at a constant angle. By providing a protrusion member that is pressed by the paper feeder, paper feeding errors can be eliminated and the load on the mechanism can be reduced.

Means for Solving the Problems In order to solve the above problems, the paper feeding device of the present invention includes a recording paper pressing plate that can move up and down to stack a plurality of recording papers, a conveying roller that conveys the recording papers, an elevating means for pressing or releasing the pressure on the recording paper stacked on the paper pressing plate against the conveying roller; and when the elevating means presses the recording paper against the conveying roller;
The recording paper pressing plate is provided with a protruding member that comes into contact with a part of the surface of the recording paper stacked on the recording paper pressing plate and presses the recording paper against the conveyance roller at a certain wrapping angle.

Effect of the Invention With the above-described configuration, the projecting member on the recording paper pressing plate hits the lowest part of the recording paper during paper feeding, deforming the entire recording paper into an upwardly convex shape, and causing the recording paper to move against the conveyance roller, which is normally the case. A larger conveyance force is obtained by increasing the pressure contact area by making the recording paper wrap around the conveyance roller instead of being in pressure contact with it horizontally.

Embodiment Hereinafter, a paper feeding device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the main parts of a paper feeding device in an embodiment of the present invention. In FIG. 1, a plurality of sheets of recording paper 11 are stored in a recording paper cassette 18, and the recording paper 11 is stored in a recording paper cassette 18.
Set to 4. A conveying roller 12 serving as a paper feeding means is rotatably disposed above the recording paper cassette 18, and
A recording paper pressing plate 13 is disposed below so as to be rotatable up and down about a rotational shaft. During paper feeding, the recording paper pressing plate 13 is pressed upward by the elevating means 19 to lift the recording paper 11 stacked in the recording paper cassette 18 and press the recording paper 11 against the conveyance roller 12.

The recording paper pressing plate 13 has a single plate with a bending portion so that the recording paper 11 remains horizontal with respect to the paper feeding direction even when the recording paper 11 becomes a plurality of sheets when pressed by the elevating means 19. In addition, there is a projection member 17 on the recording paper pressing plate 13.
By providing the recording paper 11 so that the entire recording paper 11 is deformed into a convex shape and wrapping the recording paper 11 around the conveyance roller 12, a large conveyance force is obtained, and one sheet of the upper layer or After several sheets of recording paper 11 are conveyed while being guided by a guide member 14, when passing between a separate roller 15 and a reverse roller 16, only the upper layer sheet is separated and conveyed. The separation roller 15 rotates only in the transport direction, and the reverse roller 16 has a slip mechanism, so that when two or more sheets of recording paper 11 enter, it rotates in the opposite direction from the transport rotation direction, except for the upper one. The pair of sheets described above forms a sorting mechanism to automatically feed only one sheet.

As described above, according to this embodiment, the recording paper 11 is brought into contact with the recording paper 11 stacked on the recording paper pressing plate 13 and the recording paper 11 is transferred to the transport roller 1.
By providing on the recording paper pressing plate 13 a protruding member 17 that is pressed with a certain wrapping angle, paper feeding failures can be eliminated and the load on the entire apparatus can be reduced.

Note that a belt may be stretched between the conveyance roller 12 and the separate roller 15.

Effects of the Invention As described above, the present invention reduces the coefficient of friction of the recording paper in a low-temperature environment by providing a protrusion member on the recording paper pressing plate that presses the recording paper against the conveyance roller with a fixed wrapping angle. It is possible to prevent paper feeding failures due to slippage due to an increase in the amount of curl and increase in rigidity. Further, excellent effects such as being able to reduce the load on the entire apparatus can be obtained without excessively increasing the pressing force of the elevating means to prevent paper feeding failures.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the main parts of a paper feeder according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the main parts of a conventional paper feeder. 11... Recording paper, 12... Conveyance roller, 13.
...Recording paper pressing plate, 17...Protrusion member, 19...
- Lifting means.

Claims (1)

[Claims] A recording paper pressing plate that carries a plurality of sheets of recording paper and rotates up and down, a conveying roller that conveys the recording paper, and pressing or pressing the recording paper stacked on the recording paper pressing plate against the conveying roller. an elevating means for releasing, and on the recording paper pressing plate that displaces the recording paper so that when the recording paper is pressed against the conveyance roller by the elevating means, the recording paper contacts the conveyance roller at a constant wrapping angle. 1. A paper feeding device comprising: a protruding member provided at the top of the sheet feeding device;