JP2002370838A - Sheet material separating conveyance device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high quality sheet material separating conveyance device preventing feeding failure or the like while preventing overlapped feeding of sheet material. SOLUTION: The sheet material separating conveyance device sequentially separates and conveys a plurality of sheet materials. It is characterized by that it is provided with a separation roller 2 with a conveyance part for the sheet material formed by a frictional member, a braking member 3 abutting on the separation roller 2 and comprising a flexible member stopping at least a part of the plurality of sheet materials, and a pressing member 4 pressing the brake member 3 against the separating roller 2, and a protrusion part 2a comprising a rigid body is formed on the separation roller 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet separating and conveying apparatus for sequentially separating and conveying a plurality of sheets, and more particularly to a sheet separating and conveying apparatus used in an image forming apparatus such as a printer or a copying machine. .

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus such as a copying machine having a document reading section for reading an image of a document and an image forming section for recording an image on a recording sheet, sequentially separates and conveys the sheet material such as the document or the recording sheet. And a sheet separating and conveying device.

[0005] A conventional sheet material separating and conveying apparatus will be described with reference to FIG. As shown in FIG.
Reference numeral 2 denotes a roller for separating and conveying the sheet S as a sheet material, and cooperates with a brake member 53 formed of rubber, an elastomer member, or the like to move only the lowermost sheet of the sheet S in the direction of arrow A in the figure. Separately conveyed. Here, the brake member 53
By being pressed by the pressing member 54 in the direction of the arrow P in the drawing, the separation roller 52 is pressed, and the above operation is performed. Here, the conditions for sequentially separating and transporting the sheet S from the lowermost sheet are as follows: the friction coefficient between the separation roller 52 and the sheet S is μ1, the friction coefficient between the sheets S is μ2, the sheet S and the brake member 53. If the friction coefficient between is μ3, μ1>
μ2> μ3.

A thermal transfer recording apparatus utilizing the improvement of the conveying force by using a projection roller is disclosed in Japanese Patent Laid-Open No.
Japanese Patent Application Laid-Open No. 256965/1996 and Japanese Patent Application Laid-Open No. 8-19247.

[0005]

However, according to the above-mentioned prior art, a stable and high friction coefficient μ1 is obtained for all types of paper S (for example, electrophotographic paper or pressure-sensitive paper impregnated with silicone oil). Due to the absence of the surface material of the obtained separation roller, if the friction coefficient μ3 is set too high, the sheet S may not be sent, or if the friction coefficient μ3 is set low, the sheet S may be double fed. Had occurred.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high-quality sheet material separating / conveying apparatus which prevents double sheet feeding and does not cause non-feeding.

[0007]

In order to achieve the above-mentioned object, a typical configuration of the present invention is a sheet material separating and conveying apparatus for sequentially separating and conveying a plurality of sheet materials, wherein a conveying portion of the sheet material has friction. A sheet material conveying member formed of a member, a brake member made of a flexible member that abuts on the sheet material conveying member, and stops conveyance of at least a part of the plurality of sheet materials; and And a pressing member for pressing the sheet material conveying member, wherein a projection made of a rigid body is formed on the sheet material conveying member.

According to the above construction, by forming a projection made of a rigid body on the surface of the sheet material conveying member, it is possible to increase the friction coefficient between the sheet material conveying member and the sheet material. By setting the friction coefficient between the materials to be high, a high-quality sheet material separating and conveying device that does not cause non-feeding while preventing double feeding of the sheet material can be obtained.

Further, the length of the sheet material conveying member in the width direction orthogonal to the sheet material conveying direction is made longer than that of the brake member, and a protrusion made of a rigid body is formed at a position of the sheet material conveying member where the brake member does not contact. By forming, even if the sheet material conveying member and the brake member are in direct contact rotation when the sheet material is not interposed, the protrusion formed on the surface of the sheet material conveying member does not contact the brake member, so that the durability is improved. It is possible to supply a highly reliable sheet material separating and conveying device.

[0010] Further, the projection of the sheet material conveying member may be formed by adhering and fixing powder to the surface of the sheet material conveying member, or by kneading and fixing the powder to the inner surface of the sheet material conveying member. The sheet material separating and conveying device can be supplied at low cost.

Further, by providing a backup member at a position corresponding to the projecting portion of the sheet material conveying member, the conveying force of the sheet material conveying member can be stably and reliably obtained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the drawings. However,
The dimensions, materials, shapes, relative arrangements, and the like of the components described in the following embodiments should be appropriately changed depending on the configuration of the apparatus to which the present invention is applied and various conditions, and in particular, Unless otherwise described, the scope of the present invention is not intended to be limited to them.

[First Embodiment] An image forming apparatus provided with a sheet material separating / conveying apparatus according to a first embodiment of the present invention will be described with reference to FIG. FIG. 4 is an overall configuration diagram of an image forming apparatus including the sheet material separating and conveying apparatus according to the present embodiment. In this embodiment, a small integrated multifunction printer (hereinafter, abbreviated as MFP) having printer, copy, image reading, and facsimile functions in one unit will be described as an example of the image forming apparatus.

In the MFP shown in FIG. 4, a printer unit as an image forming unit is a laser beam printer 11 (hereinafter, printer 11) using a detachable process cartridge.
In the transport direction of the recording sheet P as a sheet to be recorded, the right side is the upstream side, and the left side is the downstream side.

The printer 11 is provided with a paper feed tray 12 for supporting a recording sheet P (a sheet material to be recorded) before image formation in a vertical direction on an upstream side, and a recording sheet after image formation on a downstream side of the main body. It has a tray 13 for face-down discharge (hereinafter abbreviated as F / D discharge) for supporting P in the vertical direction, and a face-up (F / U) discharge port for discharging straight to the downstream side. Then, the lower end of the printer paper feed tray 12 and the lower end of the F / D discharge tray 13 are connected by a conveyance path extending from right to left of the main body.
5. By placing the fixing unit 16 as close as possible, a vertical substantially U-shaped conveyance path is formed.

Next, the image reading section will be described. The image reading unit 20 is disposed on the opening / closing cover 17 of the printer 11 such that the printer paper feed tray 12 and the document paper feed tray 21 are substantially parallel to each other. Similarly to 11, the right side is the upstream side, and the left side is the downstream side. The document D is conveyed downward from the document feed tray 21 by the separation roller 2 serving as a conveyance member, and is sent to the image reading sensor 24 by the reading conveyance roller 23.

The characters, figures, and the like recorded on the original D are converted by the image reading sensor 24 into electrical signals, and the converted image data is sent to a host computer or the like and displayed on a display. It functions as a fax when transferred through an image scanner or a telephone line, and as a copy when sent to a printer as it is and printed. Since one device has a plurality of functions, it is called a multi-function printer (MFP).

The document D that has passed through the image reading sensor 24 is
The sheet is conveyed downstream by the reading and discharging rollers 26, sequentially discharged onto the document discharging tray 28, and stacked.

Next, the sheet separating and conveying apparatus according to the first embodiment will be described with reference to FIGS. FIG. 1 is a central sectional view of the sheet material separating and conveying apparatus, and FIG. 2 is a partially detailed perspective view of FIG.

As shown in FIG. 1, a separation roller 2 as a sheet material conveying member is a roller member for separating and conveying a document D as a sheet material, and a brake member 3 made of rubber, an elastomer member or the like. Only the bottom sheet of the document D is separated and conveyed in the direction of arrow A in FIG. Here, the brake member 3 is pressed by the separation roller 2 by being pressed in the arrow P direction in the figure by the pressing member 4 made of a metal flexible member, and performs the above-described operation.

The conditions for separating and transporting the document D sequentially from the lowermost sheet are as follows: the friction coefficient between the separation roller 2 and the document D is μ1, the friction coefficient between the documents D is μ2, the document D and the brake If the friction coefficient between the members 3 is μ3, μ1> μ2
> Μ3.

On the surface of the separation roller 2, a projection 2a formed of a rigid body is provided. In this embodiment,
As shown in FIG. 2, the length of the separation roller 2 in the width direction (the direction orthogonal to the sheet material conveyance direction) is longer than the brake member 3, and the separation roller 2 is provided at a position where the brake member 3 does not contact. A projection 2a is formed.

In this embodiment, as shown in FIG.
The projection 2a is provided on the separation roller 2 outside the brake member 3 in the width direction (the direction orthogonal to the sheet material conveyance direction), but may be provided on the entire surface of the separation roller 2.

As described above, by arranging the projection 2a formed of a rigid body on the surface of the separation roller 2, it becomes possible to increase the friction coefficient μ1, and by setting the friction coefficient μ3 higher. In addition, a high-quality sheet material separation / conveying apparatus that does not cause non-feeding while preventing double feeding of sheet materials can be obtained.

Further, by disposing the projection 2a at a position where the brake member 3 does not contact the separation roller 2, even if the separation roller 2 and the brake member 3 rotate directly when there is no sheet material. Since the protrusion 2a provided on the surface of the separation roller 2 does not contact the brake member 3, it is possible to supply a highly durable sheet material separation and conveyance device.

The protruding portion 2a may be an inorganic material such as ceramics or a rigid material such as metal powder adhered and fixed to the surface of the separation roller 2, or may be kneaded and arranged inside the separation roller 2. Is also good. Further, a part of the separation roller 2 may be formed of metal, and the surface may be plastically worked to provide a projection. With this configuration, it is possible to supply the sheet material separating / conveying device at low cost.

Further, the height of the projection 2a of the separation roller 2 may be 1 μm to 990 μm.
The sheet material separating and conveying device can be supplied at low cost.

In the present embodiment, the separation roller which is a roller member has been described as an example of the sheet conveying member. However, the present invention is not limited to this. For example, another member such as a belt member may be used. It may be.

[Second Embodiment] Next, a sheet separating apparatus according to a second embodiment will be described with reference to FIG. In FIG. 3, the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof will be omitted. FIG. 3 only shows the present embodiment to the extent that the present embodiment can be understood, and therefore only schematically shows the shapes, dimensions, and arrangements of the components.

In the present embodiment, as shown in FIG.
The backup member 5 is disposed to face the projection 2a in the sheet material separating / conveying device described in (1). In FIG. 3, the backup member 5 is rotatably supported, and is pressed down by the pressing member 4 in the direction of the arrow P1 in the figure, and the document D is conveyed by the cooperation of the separation roller 2 and the backup member 5. I do.

As described above, the protrusion 2a of the separation roller 2
By disposing the backup member 5 at the opposing portion of the above, the conveyance force of the separation roller 2 to the document D can be stably and reliably obtained by stabilizing the force of pressing the document D against the protrusion 2a. Can be.

[Other Embodiments] In the above-described embodiment,
Although a printer has been illustrated as an example of the image forming apparatus, the present invention is not limited to this, and may be another image forming apparatus such as a scanner, a copier, a facsimile apparatus, and may be used in the image forming apparatus. A similar effect can be obtained by applying the present invention to the sheet material separating and conveying device.

Further, in the above-described embodiment, the sheet material separating / conveying apparatus for sequentially separating / conveying a document or the like to be read is exemplified, but the present invention is not limited to this.
For example, a similar effect can be obtained by applying a sheet material separating and conveying device that sequentially separates and conveys a sheet material such as recording paper as a recording target.

Further, in the above-described embodiment, the electrophotographic method is exemplified as the recording method, but the recording method is not limited to this, and another recording method such as an ink jet method may be used.

[0035]

As described above, according to the present invention,
By forming a projection made of a rigid body on the surface of the sheet conveying member, it is possible to increase the coefficient of friction between the sheet conveying member and the sheet, thereby increasing the friction coefficient between the brake member and the sheet. By setting, it is possible to obtain a high-quality sheet material separation / conveyance apparatus in which double feeding of sheet materials is prevented and no non-feeding occurs.

Further, the length of the sheet material conveying member in the width direction orthogonal to the sheet material conveying direction is made longer than that of the brake member, and a protrusion made of a rigid body is formed at a position of the sheet material conveying member where the brake member does not contact. With this configuration, even if the sheet material conveying member and the brake member are in direct contact rotation when the sheet material is not interposed, the protrusion formed on the surface of the sheet material conveying member does not contact the brake member, so that the durability is improved. It is possible to supply a highly reliable sheet material separating and conveying device.

Further, the projection of the sheet conveying member may be formed by fixing powder to the surface of the sheet conveying member, or by kneading and fixing the powder to the inner surface of the sheet conveying member. The sheet material separating and conveying device can be supplied at low cost.

Further, by disposing the backup member at a position corresponding to the projecting portion of the sheet material conveying member, the conveying force of the sheet material conveying member can be stably and reliably obtained.

[Brief description of the drawings]

FIG. 1 is a central cross-sectional view of a sheet conveying apparatus according to a first embodiment.

FIG. 2 is a partially detailed perspective view of FIG. 1;

FIG. 3 is a partially detailed perspective view of a sheet conveying apparatus according to a second embodiment.

FIG. 4 is an overall configuration diagram of an image forming apparatus including a sheet material separating / conveying apparatus according to the embodiment;

FIG. 5 is a central sectional view of a conventional sheet conveying apparatus.

[Explanation of symbols]

 D ... Document P ... Recording paper 2 ... Separation roller 2a ... Protrusion 3 ... Brake member 4 ... Pressing member 5 ... Backup member 11 ... Printer 12 ... Printer paper feed tray 13 ... F / D discharge tray 14 ... Paper feed unit 15 … Process cartridge 16… Fixing unit 17… Opening / closing cover 20… Image reading unit 21… Document feed tray 23… Reading and conveying roller 24… Image reading sensor 26… Reading and discharging roller 28… Document discharging tray

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) G03G 15/00 516 G03G 15/00 516 F term (reference) 2H072 BA03 BA13 CA01 JA02 JA05 JB01 JB05 JC07 JC08 3F343 FA02 FB02 FB04 FC01 GB02 GC01 GD01 HA12 JA12 JA19 JD04 JD08 JD09 JD22 JD35 JD38 JD39 KB05 LA03 LC27 LD04 MB03 MB14 MC26

Claims (9)

[Claims] 1. A sheet material separating and conveying device for sequentially separating and conveying a plurality of sheet materials, wherein the sheet material conveying section abuts on the sheet material conveying member formed of a friction member, and the sheet material conveying member. A brake member made of a flexible member that stops conveyance of at least a part of the plurality of sheet materials; and a pressing member that presses the brake member against the sheet material conveyance member. A sheet material separating / conveying device characterized in that a projection made of a rigid body is formed on the sheet material. 2. The sheet material conveying member has a length in a width direction orthogonal to the sheet material conveying direction longer than the brake member, and a rigid protrusion is formed at a position of the sheet material conveying member where the brake member does not contact. The sheet material separating and conveying device according to claim 1, wherein: 3. The sheet material separating and conveying device according to claim 1, wherein the sheet material conveying member is a roller member. 4. The sheet material separating and conveying apparatus according to claim 1, wherein the pressing member is made of a metal flexible member. 5. The height of the projection of the sheet material conveying member is one.
The sheet material separating and conveying device according to claim 1, wherein the height is from μm to 990 μm. 6. The sheet material separating apparatus according to claim 1, wherein the projections of the sheet material conveying member are formed by adhering and fixing powder to the surface of the sheet material conveying member. Transport device. 7. The sheet material according to claim 1, wherein the protrusions of the sheet material transport member are formed by kneading and fixing powder to an inner surface of the sheet material transport member. Separation transfer device. 8. The sheet material separating and conveying apparatus according to claim 1, wherein a backup member is provided at a position corresponding to a projecting portion of the sheet material conveying member. 9. An image forming apparatus having one or both of image reading means for reading an image of a sheet material to be read and image forming means for forming an image on a sheet material to be recorded, wherein the sheet materials are sequentially separated. An image forming apparatus comprising the sheet material separating / conveying device according to claim 1 as a sheet material separating / conveying device for conveying.