JPH04209143A - Paper sheet feeder - Google Patents

Abstract

PURPOSE:To make a device compact and reduce sheet tractive force with low noise in the sheet feeder of a copying machine or the like which consists of a sheet feed roller, a separating spring member, and a carrier spring member by bending a contacting inclined surface to the edge of sheet at a prescribed divergent angle from an upper position of the sheet feed roller to form it at the edge of the carrier spring member. CONSTITUTION:A carrier spring member 20 formed at the upper part of a sheet feed roller 16 with a plate spring material is inclined and disposed so that a carrier direction to the placing surface of a sheet tray 13 may be kept lower. A separate spring member 21 which is farmed with a plate spring material pressed against an approximately upper part of the sheet feed roller 16 is installed on the way of the carrier spring member 20. On the top edge of the carrier spring member 20, at an angle theta which can lead the top edge of the sheet to a surface of the sheet feed roller 16, namely, at the angle theta which is 90 degree or more on the sheet feed roller 16 side, a contacting inclined surface 24 is bent to a down inclination.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) The present invention is applicable to, for example, a facsimile machine, a copying machine, an optical reading device, etc., in which a plurality of sheets of paper loaded in a stacked state are processed one by one. The present invention relates to a paper feeding device that separates and sequentially feeds paper to a predetermined paper feeding position.

(Prior Art) As shown in FIG. 4, this type of paper feeding device conventionally has a paper feeding roller 2 disposed at the lower front end of a paper tray 1 on which a plurality of sheets of paper are loaded in a stacked state. A pad member 4 having a rubber pad 3 that contacts the paper feed roller 2 is disposed above the paper tray 1, and a leaf spring is provided above the pad member 4 to press the rubber pad 3 of the pad member 4 against the paper feed roller 2. A structure in which a member 5 is provided is adopted. In the paper feed device having this structure, a plurality of sheets of paper 6 are stacked on the paper tray 1, and when the paper feed roller 2 is driven to rotate in the direction of the arrow, the sheets are fitted onto the outer periphery of the paper feed roller 2. The paper 6 is pulled out by the friction force of the rubber material and the pressing force of the spring member 5 that presses the paper 6 against the paper feed roller 2 via the pad member 4, and the paper feed roller 2 is pulled out by the friction of the rubber pad 3 of the pad member 4. The upper layer of paper 6 in contact with the sheet 6 is pressed by the rubber pad 3, and the bottom layer of paper 6 in contact with the paper feed roller 2 is separated and sent out.

Further, as shown in FIG. 5, a paper feed roller 2 is disposed at the lower front end of the paper tray 1 into which a plurality of sheets of paper are loaded in a stacked state, and a leaf spring member presses the paper 6 against the paper feed roller 2. 7
is provided, and when the paper feed roller 2 is rotationally driven in the direction of the arrow,
Among the sheets of paper 6 loaded in a stacked state on the paper tray 1, the lowest layer of paper 6 is pressed by the leaf spring member 7 that presses against the paper feed roller 2, and the friction of the leaf spring member 7 causes the paper feed roller to 2 or the leaf spring member 7 on the upper layer of the paper 6
The sheet 6 in the lowest layer that has come into contact with the sheet feeding roller 2 is separated and sent out.

(Problem to be Solved by the Invention) In the paper feeding device having the conventional structure shown in FIG. 6 is pulled out, separated one by one by the rubber pad 3 of the pad member 4, and sent out one by one. However, depending on the stacking thickness of the sheets 6 pulled out between the paper feed roller 2 and the pad member 4, the paper 6 is separated from the paper feed roller 2. The pressing force of the spring member 5 that presses the paper 6 changes, and especially when the stacking thickness of the paper 6 changes at the time when - sheets of paper 6 have been fed, the pressing force of the spring member 5 changes, so that the separation effect of the paper 6 is reduced. There is a problem in that paper feeding failures such as double feeding of multiple sheets of paper 6 or failure to feed the paper 6 easily occur.

Further, since the rubber pad 3 of the pad member 4 is pressed against the paper 6 and holds the upper layer of the paper 6 fed out by the paper feed roller 2, the rubber pad 3 of the pad member 4 is required to securely hold the paper 6. , the pad member 4 must be pressed against the paper feed roller 2 with a strong pressing force (several 100 g). Therefore, the separation and feeding resistance of the paper 6 is very large, so the load to feed the paper 6 is large.
The electric motor that rotationally drives the paper feed roller 2 needs to be large enough to handle its load, and the larger the electric motor, the louder the drive noise and the sound of the rubber pad 3 and the paper 6 rubbing against each other. There were problems such as increased noise, and furthermore, a large tensile force was applied to the paper 6, causing the paper 6 to elongate.

Further, since the pad member 4 and the spring member 5, which have a complicated structure made up of multiple parts, are used, there are problems in that the cost is high and the paper feeding device becomes large.

Further, in the conventional structure shown in FIG. 5, the paper feed roller 2
The pressing force of the leaf spring member 7 that presses the paper 6 against the paper feed roller 2 changes depending on the stacking thickness of the paper 6 drawn between the paper 6 and the leaf spring member 7, and especially when the feeding of the - sheet of paper 6 is finished. If the laminated thickness of the paper 6 changes at this point, the pressing force of the spring member 5 changes, which tends to affect the separating action of the paper 6, resulting in paper feeding problems such as double feeding of multiple sheets of paper 6 or not being fed. There are problems in that defects are likely to occur and it is difficult to determine the distance between the leaf spring member 7 and the paper feed roller.

The present invention has been made in view of the above-mentioned problems, and it is possible to reliably separate and send out sheets of paper one by one.
To provide a paper feeding device which can reduce the driving load of a paper feeding roller, reduce the size of an electric motor, reduce noise, reduce the effect of tensile force on paper, reduce costs, and achieve miniaturization. It is something.

[Structure of the invention]

(Means for Solving the Problems) A paper feeding device of the present invention is a paper feeding device that separates sheets of paper loaded in a stacked state one by one and sequentially feeds out the stacked sheets. A paper feed roller that comes into contact with the bottom surface of the lower layer, and a paper feed roller that comes into contact with the top surface of the top layer of the stacked paper, presses the stacked paper against the paper feed roller to transfer one sheet of the bottom layer to the top layer. A separating spring member to be separated from the sheet is held in contact with the leading edge of the stacked sheets facing downstream from the sheet pressing position of the separating spring member of the paper feeding roller, and the leading edge and the feeding sheet are held in contact with each other. a conveying spring member having a bent abutting inclined piece portion for conveying a sheet of paper separated from the upper layer of paper between the roller and the upper layer of paper, the abutting inclined piece of the conveying spring member; The portion is bent at an angle of 90° or more, which is a spreading angle with respect to the vertical direction from a position above the paper feed roller.

(Function) When the paper feeding device of the present invention is loaded with a plurality of sheets of stacked paper, the leading edge of the paper is held in contact with the abutting inclined piece of the conveyance spring member, and the lower surface of the bottom layer of paper is It comes into contact with the roller. When the paper feed roller is driven to rotate, the bottom sheet of paper that is in contact with the paper feed roller is separated by the frictional force of the paper feed roller and the pressing force of the separation spring member, and the sheet is moved upward. It is separated from the other paper and sent out. At this time, the spring force of the separation spring member applied to the paper is sufficient to separate the sheets one by one, so the bottom layer of paper drawn in by the paper feed roller and the top layer of paper are Since the frictional force with Due to the separation force that resists the spring force, the paper is trapped between the tip of the abutting slanted piece and the paper feed roller, and the paper is separated from the part sandwiched between the separation spring member and the paper feeding roller to the abutting slanted piece. The part between the tip of the paper and the paper feed roller is wrapped around the paper feed roller, and the abutting slanted piece is bent toward the paper feed roller at an angle of 90° or more. As a result, the contact area between the paper and the paper feed roller is expanded, a force for transporting the paper is obtained, and the paper is reliably separated and sent out one by one.

(Embodiment) Next, the configuration of an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

Reference numeral II denotes a paper feeding device that feeds sheets of paper 12 such as multiple sheets of manuscript paper for transmission by a facsimile machine one by one.This paper feeding device 11 has a paper tray 13.
The sheets 12 stacked on top are loaded.

The sheets of paper 12 stacked on this paper tray 13 are separated and sent out one by one from the paper feeder 11 to the conveyance path 14.
It is pressed and read by an image sensor provided in the middle of the conveyance path 14, and is further discharged from the end of the conveyance path 14 by a plurality of discharge rollers.

As shown in FIG. 1, the paper feeding device 11 includes a rotating shaft 15 that is rotatably driven by an electric motor (not shown) at the lower front end of the paper tray 13. A paper feed roller 16 made of a material is fixed, and the upper portion of the outer periphery of this paper feed roller 16 is in a plane with the paper loading surface of the paper tray 13.

Further, the conveyance path 1 is located on the feeding side of the paper feed roller 16.
4 is formed substantially horizontally at a position slightly lower than the paper loading surface of the paper tray 13.

Further, above the paper feed roller 16, a conveyance spring member 20 made of a leaf spring material is arranged so as to be inclined to be lower in the paper conveyance direction with respect to the placement surface of the paper tray 13. A separation spring member 21 made of a leaf spring material and pressed toward the road side of the paper feed roller 16 is provided on the conveyance spring member 20 . The separation spring member 21 is inclined downwardly at an obtuse angle from the conveyance spring member 20 toward the delivery side of the paper 12, and its leading end is positioned so that the upper surface of the leading end side of the stacked sheets 12 is positioned above the outer periphery of the paper feed roller 16. It has a pressing part 23 that comes into contact with it so as to press it.

Further, the tip of the conveyance spring member 20 has an angle θ0 of 90' or more toward the paper feed roller 16 side, which allows the tip of the paper 12 to be guided toward the surface of the paper feed roller 16. An abutting inclined piece part 24 is bent downward and the tip of this abutting inclined piece part 24 is located below the pressing part 23 of the separation spring member 21 and presses the sheet feeding roller 16. It is facing the sending side. That is, the pressing portion 23 of the separation spring member 21 and the conveyance path 14
The height dimension 12 between the distal end edge of the abutting inclined piece portion 24 of the conveyance spring member 20 and the conveyance path 14 is shorter than the height dimension l between the conveyance spring member 20 and the conveyance path 14. The tip end edge of the abutment inclined piece portion 24 of the conveying spring member 20 is located below the pressing portion 23 of the separation spring member 21 and facing downstream from the pressing portion 23 of the parentheses on which the paper feed roller 16 is fed. ing. The abutting inclined piece part 24 of this conveyance spring member 20 abuts and holds the leading edge of the stacked sheets 12, and this abutting inclined piece part 2
A sheet of paper 12 that has been separated from the upper layer of paper and sent out is conveyed between the leading edge of the sheet of paper 4 and the paper feed roller 16.

The spring force of the pressing portion 23 of the separating spring member 21 is set to a pressing force necessary to separate the sheets 12 one by one, for example, several tens of grams.

Next, the operation of this embodiment will be explained.

When a plurality of stacked sheets of paper 12 are inserted along the paper tray 13, the leading edge of the paper 12 is guided to a position above the outer periphery of the paper feed roller 16. Further, the leading edge of the paper 12 guided onto the paper feed roller 16 is held in contact with the abutting inclined piece 24 of the conveyance spring member 20, as shown in FIG.

At this time, the pressing force against the stacked sheets 12 by the pressing portion 23 of the separation spring member 21 is the pressing force necessary to separate the sheets 12 one by one.

When the paper feed roller 16 is driven to rotate, the lowest layer of paper 12 in contact with the paper feed roller 16 is moved by the frictional force of the paper feed roller 16 and the pressing force of the pressing portion 23 of the separation spring member 2I. The paper 12 is pulled forward and separated from the upper layer paper 12, and as shown in FIG. By entering, a conveying force is obtained and sent out to the conveying path 14.

At this time, the force applied to the paper 12 is
Since the pressing force by the pressing unit 23 of No. 1 is sufficient, the bottom layer of paper 12 pulled out by the paper feed roller 16 and the paper 1 of the upper layer
2 is small, and the upper layer of paper 12 is held in contact with the abutting inclined piece 24 of the conveyance spring member 20, so that multiple sheets of paper 12 are not fed in duplicate or are not fed out. This prevents paper feeding errors from occurring.

Then, due to the separation force that resists the spring force of the conveying spring member 20, the bottom layer of paper 12 is crowded between the tip of the abutting inclined piece 24 and the paper feed roller 16, and the paper 12 is pushed by the separation spring member 21. From the part sandwiched between the part 23 and the paper feed roller 16 to the part sandwiched between the tip of the abutting inclined piece part 24 and the paper feed roller 16, the sheet wraps around the paper feed roller 16. Moreover, since the abutting inclined piece is bent toward the downstream side of the paper feed roller 16 with a spread angle θ0 of 90° or more, the contact area between the paper 12 and the paper feed roller 16 is expanded, and the contact area of the paper 12 is increased. A conveying force is obtained, and the sheets 12 are reliably separated and sent out one by one, and the last sheet is certainly sent out.

In addition to being able to prevent the occurrence of paper feeding failures as described above, the driving load on the paper feeding roller 16 is small, and the electric motor that rotates the paper feeding roller 16 can be downsized. Noise can be reduced by eliminating friction points between the members and the paper 12, and no large tensile force is applied to the paper 12, making it possible to prevent the paper 12 from elongating.

Note that the abutting inclined piece portion 24 of the conveyance spring member 20 has an expanding and bending angle θ0 with respect to the vertical direction from the position above the paper feed roller, or this angle θ0 is
This angle θ0 is set to a large value for paper with strong stiffness, and a small angle for paper with weak stiffness.

In addition, in the above embodiments, the facsimile paper feeding device has been described, and various types of devices such as copying machines and optical reading devices that separate sheets loaded in a stacked state one by one and feed them one by one to a predetermined paper feeding position are also applicable. Applicable to paper feeding devices.

〔Effect of the invention〕

According to the present invention, a plurality of sheets of paper loaded in a stacked state are
The leading edge is held in contact with the contact inclined piece of the conveying spring member,
The bottom surface of the bottom layer of paper is in contact with the paper feed roller, and the bottom layer of paper that is in contact with the paper feed roller by the paper feed roller is rotated and pressed by the frictional force of the paper feed roller and the separation spring member. A separation force acts on the paper and the paper is separated from the upper paper and sent out, and at this time, the spring force of the separation spring member applied to the paper is sufficient to only have the pressing force necessary to separate the paper one by one. Therefore, the frictional force between the bottom layer of paper pulled in by the paper feed roller and the paper in the upper layer is small, and only the bottom layer of paper is pulled out by the paper feed roller, and the upper layer paper is pulled out by the contact slope of the conveyance spring member. The bottom layer of paper is held in contact with one of the pieces, and the bottom layer of paper enters between the tip of the contacting inclined piece and the paper feed roller by the separation force that resists the spring force of the conveyance spring member, and the paper is separated from the separation spring member and the paper feed roller. The part between the part sandwiched between the paper roller and the tip of the abutting inclined piece and the paper feed roller wraps around the paper feed roller, and
Since the abutment slanted piece is bent toward the paper feed roller side with an expansion angle of 90 degrees or more, the contact area between the paper and the paper feed roller is expanded, paper conveyance force is obtained, and the paper is securely transported. Since it is possible to separate and send out one sheet at a time, and there is no need to apply strong pressing force to the paper, it is not affected by changes in the stacking thickness of the paper, and the paper can be reliably separated and sent out one by one. This makes it possible to prevent paper feeding failures. Additionally, since there is no need to press the paper against the paper feed roller with a strong spring force, the load driving the paper feed roller can be reduced and the electric motor can be made smaller. By abolishing it, noise is reduced, no large tensile force is applied to the paper, and elongation of the paper can be prevented. Furthermore, the structure is simple, and costs can be reduced and miniaturization can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the paper feeding device of the present invention, FIGS. 2 and 3 are cross-sectional views of the same operating state, FIG. 4 is a cross-sectional view of a conventional paper feeding device, and FIG. 5 is a sectional view of yet another conventional paper feeding device. DESCRIPTION OF SYMBOLS 11... Paper feed device, 12... Paper, 16... Paper feed roller, 20... Conveyance spring member, 21... Separation spring member, 24
...Abutting inclined surface.

Claims (1)

[Claims] (1) In a paper feeding device that separates and sequentially feeds a plurality of stacked sheets of paper one by one, a paper feeding roller that comes into contact with the bottom surface of the lowest layer of the stacked papers; and a separation spring member that comes into contact with the upper surface of the uppermost layer of stacked sheets of paper and presses the stacked sheets of paper against the paper feed roller to separate the bottom layer of paper from the upper layer of paper; The leading edges of the stacked sheets facing downstream from the paper pressing position by the separation spring member are held in contact with each other, and separated from the upper layer of paper between the leading edge and the paper feed roller and sent out. and a conveying spring member formed by bending an abutting inclined piece part for conveying a sheet of paper, and the abutting inclined piece part of the conveying spring member is arranged vertically from a position above the paper feed roller. A sheet feeding device characterized in that the sheet feeding device is bent and formed at an angle of 90° or more, which is a spreading angle.