JPH07215521A - Paper feeding device - Google Patents

Abstract

PURPOSE:To provide a sheet feeding device causing no double feed or no missed feed even when many sheets are fed to a sheet feed separation section in any whole layout in any assembling work by providing no stopper adjacently on this side of a sheet pressing roller. CONSTITUTION:A fixed stopper 11 limiting the quantity of sheets fed to a sheet feed separation section 20 arranged on this side of the sheet feed side of a blade 3 in the sheet feed separation section 20 having a sheet feed roller 4 and the blade 3 kept in contact with it at its tip.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device such as a copying machine, a facsimile, a printer and a scanner.

[0002]

2. Description of the Related Art Conventionally, in a paper feeding apparatus of this type, if a large amount of paper such as originals is fed to a paper feeding / separating section, double feeding or non-feeding is likely to occur. A device disclosed in Japanese Patent Laid-Open No. 61-60548 is proposed, which is as shown in FIG. 11, and is formed between the paper feeding roller 36 and the paper pressing roller 37 of the paper feeding separating section. The sheet 2 on the sheet stacking table 38 is fed out by the nip that is formed, and a stopper 39 is provided in front of the sheet pressing roller 37, and this stopper 39 limits the amount of sheet to be supplied in front of the nip. Therefore, only one sheet that is in direct contact with the paper feed roller 36 is fed out.

[0003]

However, in such a structure, since the stopper is provided adjacent to the front side of the paper pressing roller, the stopper is placed at such a position in consideration of the overall layout and assembly work. However, there is a problem in that it cannot be adopted if it cannot be placed.

Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional paper feeding device and to prevent the stopper from being provided adjacent to the front of the paper pressing roller. It is an object of the present invention to provide a paper feeding device that does not cause double feeding or non-feeding when a large amount of paper is fed to the paper feeding / separating unit, regardless of the type.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a sheet feeding / separating section having a sheet feeding roller and a blade whose tip abuts against the sheet feeding roller. It is characterized in that a fixed stopper is provided which is arranged in front of the blade on the paper supply side and limits the amount of paper to be supplied to the paper feed separating section. Claim 2
According to another aspect of the present invention, in a paper feeding / separating unit having a paper feeding roller and a blade whose tip is in contact with the paper feeding roller, a fixed stopper is disposed in front of the paper feeding side of the blade to limit the amount of paper fed to the paper feeding / separating unit. Is provided, an auxiliary stopper made of an elastic member is provided adjacent to the fixed stopper on the paper supply side, and the auxiliary stopper preliminarily separates the paper to be supplied to the paper separation unit. is there. The invention of claim 3 is characterized in that, in the invention of claim 2, the auxiliary stopper is provided with a plurality of preliminary separating portions having different elastic forces.

[0006]

When the operation described above is started, the sheet set on the sheet mounting plate is supplied to the sheet feeding separating section in which the sheet feeding roller is rotating, abuts on the fixed stopper, and the amount of the sheet is supplied. In addition, the leading edge of the paper abutting against it is wedged by the leading end of the fixed stopper, and only the lowermost one sheet is sequentially separated by the operation of the blade and the feeding roller of the paper feeding and separating unit. The sheet is fed and fed, and this one sheet is conveyed by the pair of conveying rollers. Then, at this time, the sheet fed toward the sheet separating section is pre-separated by the auxiliary stopper before contacting the fixed stopper, and in this case, when the auxiliary stopper includes a plurality of pre-separating portions having different elastic forces. Will be preliminarily separated according to the frictional force between the sheets.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the first embodiment of the present invention shown in FIGS. 1 to 3, 1 is a sheet placing plate, 2 is a sheet placed on it, 4 is a sheet feeding roller, and 5 is a machine frame whose base end is not shown. Is a holder swingably supported by a support shaft 18, and is biased downward by a spring 14 to support a blade 3 facing the paper feed roller 4 at its tip end. The paper feed roller 4 and the paper roller 4 constitute a paper feed separation unit 20, 6 is a pickup roller which can be displaced in the vertical direction by an operating member (not shown), 7 is a pair of transport rollers provided in front of the paper feed roller 4, 8 is a reading roller arranged on the upper part of the contact glass 9, 10 is a pair of discharge rollers arranged in front of it, and 11 is arranged with its tip positioned behind the tip of the blade 3. A fixed screw that prevents paper from being fed. A topper 12 is a swing stopper whose base end is swingably supported by a support shaft 19 on a machine frame (not shown), and its front end contacts the front end of the paper 2 when the paper is set. Similarly, the base end is swingably supported by a support shaft 19 and is biased downward by a spring 15 to press the upper surface of the paper, and 16 is a paper detection sensor. As shown in FIG. 3, the fixed stopper 11 has a gate shape, both legs 22 are inclined toward the front, and the tip of the blade 3 extends forward in a space 23 in the middle thereof. .

In the above-mentioned one, the sheet placing plate 1
After the paper feed roller 4 rotates, the paper 2 set in
The rotating pickup roller 6 moves upward to contact the sheet 2, and the lower end of the sheet 2 forms a wedge shape as shown in FIG. The paper is fed toward the fixed stopper 11 to limit its supply amount, and the leading end 21 of the paper that abuts against the fixed stopper 11 is wedged by the leading end 25 of the fixed stopper 11 to form a paper feed separation unit. By the operation of the blade 3 of 20 and the paper feed roller 4, only the lowermost one sheet is sequentially separated and fed,
The one sheet 2 is conveyed by the pair of conveying rollers 7. Then, after being detected by the paper detection sensor 16, the reading roller 8 reads the paper on the upper portion of the contact glass 9 while preventing the floating, and the paper is discharged by the paper discharge roller pair 10.

In the case of this embodiment, the fixed stopper 11 is shown in FIG.
The inclination angle φ of both leg portions 22 shown in FIG. 2 is in the range of 0 ° ≦ φ ≦ 30 °, and the distance t between the tip of the tip portion 25 and the apex 24 of the sheet feeding roller 4 is 0 mm ≦ t ≦ 0.6 mm. Within the range of, the distance x between the tip of the tip 25 and the contact portion 26 of the blade 3 and the paper feed roller 4 x
Is in the range of 1 mm ≦ x ≦ 10 mm, each positional relationship satisfies the conditions in the respective ranges, and when the tip of the tip end portion 25 is a blunt and sharp edge, the paper 2
The fixed stopper 11 can stably separate the leading edge of the sheet 2 into a wedge shape without supplying a large amount of paper or vice versa.

Many parts of the second embodiment shown in FIGS. 5, 6 and 7 are the same as those of the first embodiment. Therefore, such parts are designated by the same reference numerals and their description is omitted. , Mainly different parts will be described. An auxiliary stopper 30 having an elastic force is additionally provided at the rear portion of the fixed stopper 11, and this auxiliary stopper 30 is made of phosphor bronze, SUS material or polymer mylar, etc., and as shown in FIG. Both legs 29
Is arranged so as to be opposed to the space 28 between the leg portions 22 of the fixed stopper 11 and the blade 3, and is attached to the fixed stopper 11. The sheet 2 fed toward the separating portion 20 is first pre-separated by the auxiliary stopper 30 and then wedged by the tip portion 25 of the fixed stopper 11. The auxiliary stopper 30 is φ,
When t and x are in the same range as in the first embodiment, the distance s of the free portion above the bent portion of the auxiliary stopper 30 is 0 mm ≦ s.
When pasted so that it is within the range of ≦ 20 mm, the leading edge 21 of paper 2
Can be sorted into a wedge shape.

Since many parts of the third embodiment shown in FIGS. 8 to 10 are similar to those of the second embodiment, such parts are designated by the same reference numerals and their description will be omitted. The different parts will be described. As shown in FIG. 9, the auxiliary stopper 30 'attached to the rear portion of the fixed stopper 11 is provided with another pair of both leg portions 31 on the outside of both leg portions 29 thereof, and is preliminarily separated according to the frictional force between the sheets. Except for the points, it is similar to the second embodiment. It is preferable that the leg portions 29 near the center have a width narrower than that of the outer leg portions 31 to weaken the elastic force and make the length longer.

[0012]

The present invention is as described above, and the invention of claim 1 is, in a paper feed separating section having a paper feed roller and a blade whose front end abuts on the paper feed roller, before the blade on the paper feed side. There is a fixed stopper that limits the amount of paper that is placed and that feeds to the paper feed separation unit.Because the stopper is not installed in front of the paper pressing roller, it does not affect the overall layout or assembly work. Even in such a case, when a large amount of paper is fed to the paper feeding / separating unit, there is an effect that double feeding or non-feeding does not occur. Claim 2
According to another aspect of the present invention, in a paper feeding / separating unit having a paper feeding roller and a blade whose tip is in contact with the paper feeding roller, a fixed stopper is disposed in front of the paper feeding side of the blade to limit the amount of paper fed to the paper feeding / separating unit. Is provided, and an auxiliary stopper made of an elastic member is provided on the paper supply side adjacent to the fixed stopper, and this auxiliary stopper preliminarily separates the paper to be supplied to the paper feed separating section, so that double feeding or non-feeding is performed. It is possible to effectively prevent the occurrence of the above. According to the invention of claim 3, in the invention of claim 2, the auxiliary stopper comprises a plurality of pre-separation portions having different elastic forces, and since the auxiliary stopper pre-separates in accordance with the frictional force between the sheets, it is even more preferable. There is an effect that it is possible to more effectively prevent the occurrence of double feed, non-feed, and the like.

[Brief description of drawings]

FIG. 1 is a front view of a first embodiment of the present invention.

FIG. 2 is an enlarged front view of the main part of the above.

FIG. 3 is a side view of the above.

FIG. 4 is an explanatory diagram of a positional relationship of each part of the above.

FIG. 5 is an enlarged front view of the essential parts of the second embodiment of the present invention.

FIG. 6 is a side view of the above.

FIG. 7 is an explanatory diagram of a positional relationship of each part of the above.

FIG. 8 is an enlarged front view of the essential parts of the third embodiment of the present invention.

FIG. 9 is a side view of the above.

FIG. 10 is an explanatory diagram of a positional relationship of each part of the above.

FIG. 11 is a front view of a main part of a typical conventional example of a paper feeding device of the same type as the present invention.

[Explanation of symbols]

 1 Paper Placement Plate 2 Paper 3 Blade 4 Feed Roller 5 Holder 6 Pickup Roller 7 Conveyor Roller Pair 11 Fixed Stopper 14 Spring 20 Paper Separation Part 21 Paper Tip 22 Fixed Stopper Legs 25 Fixed Stopper Tip 29 Inner Both Legs Parts 30, 30 'Auxiliary stopper 31 Both outer legs

Claims (3)

[Claims] 1. A sheet feeding / separating unit having a sheet feeding roller and a blade whose tip is in contact with the sheet feeding roller, is fixed in front of the sheet feeding side of the blade and limits the amount of sheets fed to the sheet feeding / separating unit. A sheet feeding device, which is provided with a stopper. 2. A fixed sheet feeding / separating section having a sheet feeding roller and a blade whose tip is in contact with the sheet feeding roller, which is arranged in front of a sheet feeding side of the blade and limits an amount of sheets fed to the sheet feeding / separating section. A stopper is provided, and an auxiliary stopper made of an elastic member is provided on the paper supply side adjacent to the fixed stopper, and the auxiliary stopper preliminarily separates the paper to be supplied to the paper feed separating section. Paper equipment. 3. The sheet feeding device according to claim 2, wherein the auxiliary stopper includes a plurality of pre-separation portions having different elastic forces.