JP2835640B2 - Paper feed mechanism - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed mechanism for selectively taking out sheets one by one by a friction roller from a paper feed cassette containing a plurality of sheets. .

[Conventional technology]

Conventionally, the size of paper used in copiers and printers is determined by the standard, and sheet paper that is advantageous for the user in terms of organization and handling is mainly used. Several sheets are stored together in a paper cassette in a stacked and aligned state, and the paper
At the time of use, sheets are selectively taken out one by one from the uppermost surface or the lowermost surface of the stacking arrangement and fed to a copier, a printer or the like.

In the paper feed mechanism, various paper feed systems using a frictional force or an attraction force have been put to practical use in order to selectively separate sheets one by one from the stacked and aligned sheet paper and take out the sheet paper. Among these, the most widely used paper feeding method is a corner claw method which is extremely simple in structure and can be configured small and inexpensively.

In the corner claw method, two sets of paper feed positions are provided by pressing two corner portions (feed positions) at one end of the uppermost surface or lowermost surface of sheet paper stacked and aligned in the thickness direction in the paper feed cassette. Each of the independent corner claws applies elastic pressure from the thickness direction of the sheet paper, and furthermore, the elastic pressing of the corner claws is performed by a pressing plate and a pressing spring supporting the whole or a part of the stacked and aligned sheet paper from the thickness direction. The opposite elastic pressure is applied through the sheet paper, and the pressure and the kicking force of the friction roller pressed against the surface of the laminated sheet paper in the vicinity of the corner claw are applied to the surface of the sheet paper. This is a sheet feeding method in which sheets are buckled in the vicinity of a corner claw, and the sheet is selectively jumped and released one by one from the corner claw in the sheet feeding direction by the elastic repulsive force of the sheet paper at that time to perform sheet feeding. The two sets of corner pawls are independent of each other and are provided with a pressing spring because the sheet pawls are stably held at the time of paper feeding, and the sheet papers stored in the paper feeding cassette are last one by one. This is for reliably feeding up to one sheet.

[Problems to be solved by the invention]

In the conventional technique as described above, a corner claw-type corner is provided by applying elastic pressure to two corner portions at one end of the uppermost surface or the lowermost surface of sheet paper stacked and aligned in the thickness direction in a paper feed cassette. In order to satisfy the claw function, at least two corner claws and two springs are required, for a total of four parts, and the number of component parts cannot be reduced and the structure cannot be simplified. Had.

[Means for solving the problem]

In order to solve the above problems, in the present invention,
In order to reduce the number of component parts while basically satisfying the functions of the corner claw method, one-piece molded parts 1 made of elastic material
The function of two sets of corner claws required individually can be achieved.

[Action]

According to the above configuration, the number of components of the corner claw method can be reduced to one.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a first embodiment of a sheet feeding device according to the present invention, in which even a sheet press is performed by bending a wire having a circular or square cross section and having elasticity, and a fixing convex portion 1 in the center and near both ends. A pressing portion 2 for pressing two corner portions at one end of the sheet paper is formed. Further, a sheet paper presser 4 provided with protrusions 3 for sliding guides at both ends has a symmetrical shape in the left-right plane. .

FIG. 2 is a perspective view of a sheet feeding mechanism in which the sheet presser shown in FIG. 1 is incorporated in a sheet cassette, and a pressing plate 6 and a pressing plate incorporated in the sheet cassette 5 are shown. 6
The sheet paper 8 in the stacked and aligned state, which is elastically pressed upward from below by the pressing spring 7 positioned below, is pressed by the sheet paper retainer 4 at the two left corners in an elastically pressed state from above to below. The uppermost surface of the sheet paper 8 is pressed against the uppermost surface of the sheet paper 8 in the vicinity of the sheet paper retainer 4 and one of the uppermost surfaces of the sheet paper 8 is brought close to the sheet paper retainer 4 by the pressing and kicking force of the friction roller 9. Buckling and elastic repulsion force selectively release the sheet from the sheet presser 4 in the sheet feeding direction on the left side, thereby releasing the sheet 8 in the stacked and aligned state.
, The sheet feeding operation is always performed one by one from the uppermost surface. Here, the fixing convex portion 1 of the sheet presser 4 is fitted and fixed to the side of the sheet feeding cassette 5 in the sheet feeding direction. The fixing protrusion 1 is supported by the long holes provided at the two positions in such a manner that it can move up and down in response to a change in the pressing force of the friction roller 9, the amount of the sheet paper 8, and uneven shape. The paper sheet 8 always follows up and down movements with independent left and right spring pressures.
By functioning so as not to form a gap at the two left corners of, a stable paper feeding operation is performed.

FIG. 3 shows a second embodiment of the sheet presser of the sheet feeding mechanism according to the present invention, in which a fixing projection 10 and two left and right parallel spring portions are provided at the center and in the vicinity thereof by bending an elastic plate material.
11, a pressing portion 12 for pressing two corners at one end of the sheet paper is formed near both ends, and further, a sheet paper press 14 having a sliding guide convex portion 13 at both ends is a left and right target object. It has a shape. The sheet paper retainer 14 thus formed
Is incorporated in a paper feed cassette as in the first embodiment, and operates similarly.

FIG. 4 shows a third embodiment of a sheet presser of a sheet feeding mechanism according to the present invention, in which a fixing convex portion 15 is provided at the center and a vicinity of both ends is formed by bending a wire having a circular or square cross section and having elasticity. Are formed with pressing portions 16 for holding two corners at one end of the sheet paper, and further, at both ends, convex portions 17 for sliding guides are formed.
The sheet paper retainer 18 having the shape of the left and right sides. The sheet presser 18 thus formed is incorporated in a sheet feed cassette as in the first embodiment of the sheet presser, and operates similarly. (However, fixing projection 15
Is fixed to the bottom of the sheet feeding cassette 5 below the pressing plate 6. FIG. 5 shows a fourth embodiment of the sheet presser of the sheet feeding mechanism according to the present invention, in which a fixing projection 19 is provided at the center and one end of the sheet is provided near both ends by bending an elastic plate. 2
A pressing portion 20 for holding the corner portion of the place is formed,
A sheet paper holder 22 provided with sliding guide projections 21 at both ends.
Has a left-right symmetrical shape. The sheet presser 22 formed in this manner is incorporated in a sheet cassette as in the third embodiment of the sheet presser, and operates similarly.

〔The invention's effect〕

As described above, according to the present invention, while the corner claw function of the corner claw system is basically satisfied, the number of component parts conventionally required to be four or more to achieve the four functions of the corner claw is reduced by one by the integral molding of the elastic material. Since parts can be reduced, it is possible to simplify the structure of the paper feed mechanism used in copiers and printers, improve processing and incorporation, and obtain significant advantages in terms of cost. It is extremely large.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a sheet press of the sheet feed mechanism of the present invention, FIG. 2 is a perspective view showing a feed mechanism incorporating the sheet press of FIG. 1, and FIG. FIG. 4 is a perspective view showing a second embodiment of the sheet presser of the sheet feeding mechanism of the present invention,
FIG. 5 is a perspective view showing a third embodiment of the sheet press of the sheet feeding mechanism of the present invention, and FIG. 5 is a perspective view showing a fourth embodiment of the sheet press of the sheet feed mechanism of the present invention. 1,10,15,19 …… Fixing projections 2,12,16,20 …… Pressing parts 3,13,17,21 …… Sliding guide projections 4,14,18,22 …… Sheet paper Holder 5: Paper cassette 6: Pressing plate 7: Pressing spring 8: Sheet paper 9: Friction roller 11: Parallel spring portion

Claims (1)

(57) [Claims] A first pressing member for pressing two corner portions at one end of an uppermost surface or a lowermost surface of at least one or more sheet papers in a thickness direction, and the first pressing member. And a second pressing member for providing a reverse pressing opposite to the pressing direction through the sheet paper, wherein the first pressing member is provided at a substantially central portion. A sheet feeding mechanism comprising: a fixing portion; a pressing portion that presses a corner portion at one end of a sheet of paper; and sliding guide portions provided at both ends, and is integrally formed of an elastic material.