JP2003252469A - Paper feeding mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a paper feeding error through the cooperation between a separation sheet and a conveyance roller corresponding to the circumferential surface of the separation roller, and to prevent waste of a resource by enabling an operator to take out the separation sheet and the conveyance roller while separating them from the separation roller. <P>SOLUTION: A holder 4, disposed below a separation roller 1 and freely swingable around a shaft 4a parallel to a revolving-shaft 3a of a conveyance roller 3 at a position on the downstream side of the conveyance roller in the paper feeding direction, supports a separation sheet 2 and the conveyance roller 3 in this order from the upstream side to the downstream side in the paper feeding direction. The upper surface of the separation sheet 2 and the circumferential surface of the conveyance roller 3 are collaboratingly abutted on the circumferential surface of the separation roller 1 through the holder 4. By swinging the holder 4 in the direction of an arrow B, both the upper surface of the separation sheet 2 and the circumferential surface of the conveyance roller 3 are separated from the circumferential surface of the separation roller 1. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a sheet processing apparatus such as an image forming apparatus and forms an image of a plurality of sheets (including a sheet body other than paper such as an OHP film) stored in a storage position. The present invention relates to a sheet feeding mechanism that conveys sheets one by one to a sheet processing unit such as a copy unit.

[0002]

2. Description of the Related Art In a sheet processing apparatus such as an image forming apparatus for forming an image on a sheet, a plurality of sheets are stacked and stored at a storage position such as a sheet feeding cassette, and the image forming unit or the like is stored from the storage position. A paper feed mechanism that feeds paper one by one to the paper processing unit is used. As such a paper feed mechanism, a paper feed mechanism used in a relatively small-sized paper processing apparatus is composed of a pickup roller and a separating member. The pick-up roller rotates by bringing the peripheral surface into contact with the upper surface of the uppermost sheet of the plurality of sheets stacked and stored at the sheet feeding position and rotating the uppermost sheet from the storing position. Get out in the direction. The separating member is arranged on the downstream side of the pickup roller in the paper feeding direction, separates the plurality of sheets fed from the storage position by the rotation of the pickup roller, and guides only the uppermost sheet in the paper feeding direction. .

That is, a plurality of sheets of paper stacked and stored in the storage position may be attracted to each other by electrostatic force or frictional force, and may be positioned at the uppermost position due to friction with the peripheral surface of the rotating pickup roller. When the sheet to be fed is fed, the sheet located below the sheet may also be fed together with the uppermost sheet in the sheet feeding direction.
At least one sheet is fed toward the paper processing unit at the same time, which causes a jam in the conveyance path on the way or makes it impossible to perform proper processing in the paper processing unit. For this reason,
A separating member is provided so as to feed only one sheet toward the sheet processing unit even when a plurality of sheets are fed from the storage position by the pickup roller.

A conventional separating member comprises a separating roller located on the upper side and a separating sheet located on the lower side, and the upper surface of the separating sheet is pressed against the peripheral surface of the separating roller from below by a predetermined pressing force. The sheet is configured to pass the sheet between the peripheral surface of the separating roller rotating in the sheet feeding direction and the upper surface of the separating sheet. When the multiple sheets are fed from the storage position and the multiple sheets reach between the peripheral surface of the separating roller and the upper surface of the separating sheet, only the uppermost sheet whose upper surface contacts the peripheral surface of the separating roller Is continuously passed between the separating roller and the separating sheet by the frictional force applied from the peripheral surface of the separating roller, while the sheet located below the uppermost sheet is brought into contact with the separating sheet in the sheet feeding direction. Is prevented from moving and cannot pass between the separating roller and the separating sheet. As a result, only the uppermost sheet in the storage position passes between the separating roller and the separating sheet and is fed to the sheet processing unit.

However, the appropriate value of the pressure contact force of the separating sheet with respect to the peripheral surface of the separating roller changes according to the conditions such as the thickness of the paper stored in the storage position, the amount of paper dust, the water content, etc. When the conditions change, the pressure contact force of the upper surface of the separation sheet against the peripheral surface of the separation roller is insufficient and multiple sheets of paper pass between the separation roller and the separation sheet, or on the contrary, the pressure contact force of the separation sheet is excessive. As a result, there may be a case where the front end of the sheet is bent or a sheet feeding error such as a delay in the sheet feeding timing occurs.

Therefore, as a conventional sheet feeding mechanism, as shown in FIG. 6, the peripheral surface is pressed against the peripheral surface of the separating roller 71 on the downstream side of the separating sheet 72 in the sheet feeding direction to rotate the separating roller 71. A configuration including a driven transport roller 73 has been proposed. With this configuration, when a plurality of sheets of paper pass between the separating roller 71 and the separating sheet 72, the plurality of sheets of paper are further separated by the separating roller 71 and the transport roller 7.
3 when passing between the uppermost sheet, the frictional force acting from the peripheral surface of the rotating separating roller 71 surely passes between the separating roller 71 and the conveying roller 73, and When the uppermost sheet of paper passes between the roller 71 and the peripheral surface of the transport roller 73 whose driven rotation is stopped, the sheets other than the uppermost sheet of paper are separated between the separation roller 71 and the transport roller 73. It is said that one sheet can be fed to the sheet processing unit in a more stable state by reliably blocking the passage.

[0007]

However, in the conventional sheet feeding mechanism including the separating roller 71, the separating sheet 72 and the conveying roller 73 shown in FIG. 6, the upper surface of the separating sheet 72 and the peripheral surface of the separating roller 71 are Since the peripheral surfaces of the transport rollers 73 are pressed against each other by the elastic forces of the individual springs 74 and 75, the separation sheet 72 and the transport rollers 73 are pressed.
However, there is a problem in that the paper feed error cannot be prevented due to the fact that they move with respect to the peripheral surface of the separating roller 71 only in an independent state, and the cooperation of the two cooperates with each other. Further, when the operation of the paper processing device is stopped while the paper is stopped in the paper feed mechanism, the separation sheet 72 and the conveyance roller 73 are separated by the separation roller 7 in order to remove the paper from the inside of the paper supply mechanism.
Although it is necessary to separate the separation sheet 72 and the conveyance roller 73 from each other by one operator,
There is a problem that the paper cannot be pulled out from the inside of the paper feeding mechanism while being separated from the paper feeding device 1, and the resource is wasted due to the damage of the paper.

An object of the present invention is to enable a separating sheet and a conveying roller to be integrally operated with respect to a peripheral surface of a separating roller, and prevent a paper feeding error by cooperating with each other. (EN) Provided is a paper feed mechanism capable of removing a sheet from the inside of a paper feed mechanism while separating a separation sheet and a conveyance roller from a separation roller by one worker, and preventing waste of resources. is there.

[0009]

The present invention has the following structure as means for solving the above problems.

(1) In a paper feeding mechanism provided with a separating roller that comes into contact with the upper surface of the paper fed from the storage position and a separating sheet that comes into pressure contact with the peripheral surface of the separating roller from below, in the paper feeding direction. A conveying roller whose peripheral surface is in pressure contact with the peripheral surface of the separating roller is arranged on the downstream side of the separating sheet, and is oscillated around an axis parallel to the rotation axis of the conveying roller on the downstream side of the conveying roller in the paper feeding direction. It is characterized in that the separation sheet and the conveyance roller are supported by a single swing member.

In this structure, the separation sheet whose upper surface is in pressure contact with the peripheral surface of the separation roller and the conveyance roller whose peripheral surface is in pressure contact with the peripheral surface of the separation roller are downstream of the conveyance roller in the paper feeding direction. The sheets are arranged in this order from the upstream side to the downstream side in the paper feeding direction in a state of being supported by a single swinging member that swings around an axis parallel to the rotation axis of the. Therefore, the separation sheet and the conveyance roller operate integrally with the separation roller via the swinging member, and are disposed between the peripheral surface of the separation roller and the upper surface of the separation sheet and between the peripheral surface of the separation roller and the conveyance roller. The separating function of the separation sheet and the conveying roller works in cooperation with the sheet passing through the peripheral surface in this order.
Further, by the swinging operation of the single swinging member, both the separating sheet and the conveying roller are simultaneously separated or pressed against the peripheral surface of the separating roller.

(2) The separating sheet and the conveying roller are urged toward the peripheral surface of the separating roller by the elastic force of individual elastic members.

In this structure, the pressure contact forces of the upper surface of the separating sheet and the peripheral surface of the conveying roller with respect to the peripheral surface of the separating roller are individually set. Therefore, when a plurality of sheets are simultaneously fed from the paper feeding position, a separating sheet that separates the sheets by applying a frictional force from the flat upper surface to the lower surface of the sheet and a frictional force from the peripheral surface to the lower surface of the sheet. The pressure contact force is set according to the respective separating functions of the conveying roller that separates the sheet by applying the action.

(3) The urging force of the upper surface of the separating sheet with respect to the peripheral surface of the separating roller is larger than the urging force of the peripheral surface of the conveying roller with respect to the peripheral surface of the separating roller.

In this structure, the upper surface of the separating sheet is pressed against the peripheral surface of the separating roller with a larger urging force than the peripheral surface of the conveying roller. Therefore, when a sufficient sheet separating function is exerted between the peripheral surface of the separating roller and the upper surface of the separating sheet, and when a plurality of sheets are simultaneously fed from the paper feeding position, the plurality of sheets are separated from the separating roller. The frequency of reaching the distance between the separating roller and the conveying roller beyond the distance between the separating sheets becomes low.

(4) An extension line in the sheet feeding direction of the separation sheet is a range on the separation sheet side divided by a line connecting the rotation axis of the separation roller and the rotation axis of the conveyance roller on the peripheral surface of the conveyance roller. And intersects with the range on the separation roller side divided by the diameter of the conveying roller orthogonal to this line.

In this structure, the extension line of the separation sheet in the paper feed direction intersects with the peripheral surface of the conveying roller in a range facing the paper feed direction. Therefore, the leading edge of the sheet that has passed between the separating roller and the separating sheet comes into contact with a region of the peripheral surface of the transport roller that faces the sheet feeding direction, and the sheet that has passed between the separating roller and the separating sheet is separated by the separating roller. The paper is reliably fed via the space between the transport roller and the transport roller.

(5) The conveying roller has a hardness higher than that of the separating roller.

In this structure, the carrying roller is less likely to be deformed than the separating roller. Therefore, at the portion where the peripheral surface of the separating roller and the peripheral surface of the conveying roller are in pressure contact with each other, the peripheral surface of the separating roller is deformed so as to be convex toward the rotation shaft side of the separating roller, and passes between the separating roller and the conveying roller. It is possible to prevent the wound paper from being wrapped around the separation roller.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the case where the sheet feeding mechanism according to the embodiment of the present invention is applied to an image forming apparatus which is a sheet processing apparatus having an image forming section as a sheet processing section will be described as an example. explain. FIG. 1 is a schematic diagram showing a configuration of an image forming apparatus to which a sheet feeding mechanism according to an embodiment of the present invention is applied. The image forming apparatus 100 has an image reading unit 11 at the top.
0, the image forming unit 210 in the center, and the paper feeding unit 25 in the lower part
It is configured by arranging 0s. This image forming apparatus 100
An automatic document feeder 112 that automatically feeds a plurality of documents set on a document set tray one by one onto the document table 111 is placed on a transparent glass document table 111 arranged on the upper surface of the document table. It is equipped. In addition, the image forming unit 21
The post-processing unit 260 is mounted on one side surface of the sheet No. 0, and the multi-stage paper feeding unit 270 also serving as a mounting table is arranged below the paper feeding unit 250.

The image reading section 110 located below the document table 111 is a first scanning unit 113, a second scanning unit 114, an optical lens 115, and a photoelectric conversion element C.
An automatic document feeder 11 having a CD line sensor 116
By the operation related to 2, the image of the document placed on the document table 111 is relatively scanned and read at a predetermined exposure position. The first scanning unit 113 is equipped with an exposure lamp unit that exposes the surface of the original, and a first mirror that reflects a reflected light image from the original in a predetermined direction. The second scanning unit 114 has a second mirror and a third mirror that guide the reflected light from the document reflected by the first mirror to the CCD line sensor 116, which is a photoelectric conversion element. The optical lens 115 reflects the light reflected from the document by C
An image is formed on the light receiving surface of the CD line sensor 116.

The original image read by the original reading unit 110 is sent as image data to an image data input unit (not shown), and after being subjected to predetermined image processing on the image data, it is stored in the memory of the image processing unit. Once stored, it is read out from the memory according to the output instruction and transferred to the image forming unit 210.

The image forming section 210 includes a photosensitive drum 22.
Laser writing for forming an electrostatic latent image on the photosensitive drum 222 by emitting a laser beam in accordance with image data transferred from the charger 223 that charges 2 to a predetermined potential, the document reading unit 110, or an external device. Unit 227, photoconductor drum 22
2. A developing device 224 that supplies toner to the electrostatic latent image formed on the photosensitive drum 222 to visualize the toner image, a transfer device 225 that transfers the toner image formed on the photosensitive drum 222 to a sheet, after the transfer process. A cleaning device 226 for collecting toner and the like remaining on the photoconductor drum 222 and a peeling device 229 for peeling the sheet from the photoconductor drum 222 after the transfer process are provided. Further, the image forming unit 210 is provided with a fixing unit 217 that heats and presses the paper on which the toner image is transferred to fix the toner image on the paper. Further, on the discharge side of the fixing unit 217, a switchback path 221 for reversing the front and back of the sheet in the double-sided image forming mode for forming images on both sides of the sheet is formed.

The sheet on which the toner image has been fixed in the fixing unit 217 is switched back to the switchback path 221 if necessary.
After that, the paper is guided to the post-processing device 260 by the paper ejection roller 219, where post-processing such as stapling and punching is performed, and then the paper is ejected onto the tray 261.

The paper feeding section 250 is composed of a manual tray 254 mounted on the side of the main body, a duplex unit 255, a paper feeding tray 251 and paper feeding trays 252 and 253 provided in the multi-stage paper feeding unit 270. . Further, these paper feed trays 251 to 254 are the storage positions of the present invention,
Multiple sheets of paper are stacked and stored. The sheet feeding trays 251 to 254 are provided with a conveyance unit such as a roller that conveys the sheets fed to the image forming unit 210 to a transfer position between the photoconductor drum 222 and the transfer unit 225. The duplex unit 255 communicates with the switchback path 221 that reverses the sheet, and temporarily stores the sheet whose front and back surfaces are inverted in the double-sided image forming mode. The duplex unit 255 can be replaced with a normal paper feed tray.

Each of the paper feed trays 251 to 254 is provided with a paper feed mechanism including a pickup roller 5, a separation roller 1 and a separation sheet 2. The pickup roller 5 is configured so that the peripheral surface thereof can be selectively pressed against the upper surface of the uppermost sheet of the plurality of sheets stored in the sheet feed trays 251 to 254. The pickup roller 5 is pressed against the upper surface of the uppermost sheet to rotate at a timing synchronized with the image reading process of the image reading unit 110 and the image forming process of the image forming unit 210, and the frictional force of the peripheral surface is applied to the upper surface of the sheet. The uppermost sheet is fed in the sheet feeding direction.

The separating roller 1 and the separating sheet 2 are located on the downstream side of the pickup roller 5 in the sheet feeding direction, and the sheet fed out by the pickup roller 5 is surrounded by the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2. Pass between and. As an example, the separating roller 1 is rotated by receiving a rotational force supplied from a drive motor common to the pickup roller 5. The separating sheet 2 has a flat plate shape, and the upper surface thereof is in pressure contact with the peripheral surface of the separating roller 1 with a predetermined pressing force. As will be described later, on the downstream side of the separating sheet 2 in the paper feed direction, a cylindrical conveying roller 3 whose peripheral surface is in pressure contact with the peripheral surface of the separating roller 1 with a predetermined pressing force rotates the separating roller 1. It is rotatably arranged around a rotation axis parallel to the axis.
Therefore, the transport roller 3 rotates following the rotation of the separation roller 1.

FIG. 2 is an external view showing the construction of the main part of the paper feed mechanism of the present invention. The separation sheet 2 and the transport roller 3 which constitute the sheet feeding mechanism 10 of the present invention are supported by the holder 4 which is the swing member of the present invention. The holder 4 is arranged below the separating roller 1 and has ribs 4b, 4 exposed on the upper surface.
The lower surface of the paper feed path is constituted by c and 4d. The holder 4 supports the separated sheets 2 and the transport rollers 3 in this order from the upstream side to the downstream side in the sheet feeding direction of the arrow A direction. Further, the holder 4 is swingable around a shaft 4a parallel to the rotation shaft 3a of the transport roller 3 at a position on the downstream side of the transport roller 3 in the paper feeding direction.
The separation sheet 2 is supported by the holder 4 with its upper surface exposed to the upper surface of the holder 4, and the transport roller 3 is supported by the holder 4 with part of its peripheral surface exposed to the upper surface of the holder 4. The upper surface of the separating sheet 2 and the peripheral surface of the transport roller 3 are in contact with the peripheral surface of the separating roller 1.

FIG. 3 is a schematic side view of the main part of the paper feeding mechanism. The paper feed mechanism 10 of the present invention, as described above,
Separation roller 1, separation sheet 2, conveyance roller 3 and holder 4
In addition, the pickup roller 5 guides only the uppermost sheet fed from the sheet feeding trays 251 to 254, which is the storage position, in the sheet feeding direction of the arrow A direction. That is, depending on the paper quality of the plurality of sheets stacked and stored in the storage position and the environmental conditions, the sheets may be strongly adsorbed to each other. In such a case, the peripheral surface of the rotating pickup roller 5 is When the uppermost sheet is brought into contact with the upper surface, a single sheet or a plurality of sheets located below the uppermost sheet may be fed simultaneously. Therefore, in the paper feeding mechanism 10 of the present invention, the uppermost sheet is separated from the lower sheet by the separating roller 1, the separating sheet 2, and the conveying roller 3, and only the uppermost one sheet is accurately formed.
It can be transported to.

Therefore, in the sheet feeding mechanism 10, the separating sheet 2 fixed to the holder 4 is separated together with the holder 4 from the separating roller 1.
A spring 6 for urging the roller 4 and a spring 7 for urging the transport roller 3 axially supported by the holder 4 toward the separating roller 1 at the end of the rotary shaft 3a. The spring 6 and the spring 7 are elastic members of the present invention. As described above, the holder 4 serves as the transport roller 3 in the paper feed direction.
On the downstream side of, the shaft 4a, which is parallel to the rotation shaft 3a of the transport roller 3, is pivotable in the directions of arrows B and C.
Therefore, the holder 4 is urged by the elastic force of the spring 6 toward the separating roller 1 together with the separating sheet 2 unless an external force acts.

With the above-described structure, in the paper feeding mechanism according to this embodiment, the upper surface of the separation sheet 2 supported by the holder 4 which is a single member and the peripheral surface of the transport roller 3 are provided for the paper fed from the storage position. A plurality of sheets of paper are pressed against the peripheral surface of the separating roller 1 in this order in the sheet feeding direction in this order, and a plurality of sheets fed simultaneously from the storage position are provided between the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2, and Separation can be performed at two places between the peripheral surface of the separating roller 1 and the peripheral surface of the transport roller 3. As a result, the separation sheet 2 and the conveyance roller 3 operate integrally with the separation roller 1 via the holder 4, and between the peripheral surface of the separation roller 1 and the upper surface of the separation sheet 2, and
The separating function of the separating sheet 1 and the conveying roller 3 can be made to act in cooperation with the sheet passing between the peripheral surface of the separating roller 1 and the peripheral surface of the conveying roller 3 in this order. Therefore, even if a plurality of sheets of paper that are fed at the same time have a strong suction force and a plurality of sheets of paper pass between the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2, these sheets are separated again by the separating roller. Since the peripheral surface of 1 and the peripheral surface of the conveyance roller 3 can be separated, only the uppermost one sheet can be accurately passed in the sheet feeding direction.

The separating sheet 2 with respect to the separating roller 1
The pressure contact force of the conveying roller 3 is stronger than the pressure contact force of the conveying roller 3 with respect to the separating roller 1. As a result, a sufficient separating action is exerted between the separating roller 1 and the separating sheet 2, and even when a plurality of sheets are simultaneously fed from the storage position, the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2 It is possible to reliably reduce the number of sheets of paper that pass between the and. Therefore, even if a plurality of sheets of paper pass between the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2 at the same time, the number of sheets is sufficiently small, and the peripheral surface of the separating roller 1 and the conveying roller 3 are small. It is possible to reliably separate the uppermost sheet from the peripheral surface from the other sheets, and the sheet feeding mechanism 1
From 0, it is possible to accurately guide only the topmost one sheet in the sheet feeding direction.

Further, in the holder 4, the rotary shaft 3a of the transport roller 3 is provided on the peripheral surface of the transport roller 3 on the side opposite to the sorting roller 1 side in the normal direction at the contact portion with the peripheral surface of the sorting roller 1. Is not in contact with. That is, the holder 4 is
The rotation shaft 3a of the conveyance roller 3 is not in contact with the conveyance roller 3 in the direction of urging the separation roller 1 side, and the elasticity of the spring 6 that urges the separation sheet 1 and the holder 4 toward the separation roller 1 side. The force does not act on the transport roller 3. Therefore, by making the elastic force of the spring 6 larger than the elastic force of the spring 7, the pressure contact force of the separation sheet 2 with respect to the separation roller 1 is made stronger than the pressure contact force of the transport roller 3 with respect to the separation roller 1. You can

FIG. 4 is a schematic side view for explaining the operation of the main part of the paper feed mechanism. In the paper feed mechanism 10 of the present invention, a holder 4 that supports the separation sheet 2 and the transport roller 3
Is swingable in the directions of arrows B and C around a shaft 4a arranged on the downstream side of the transport roller 3 in the paper feeding direction. As shown in FIG. 3, when the upper surface of the separating sheet 2 and the peripheral surface of the conveying roller 3 are brought into contact with the peripheral surface of the separating roller 1 with a predetermined pressure contact force, the holder 4 is swung in the direction of arrow B. As shown in FIG. 4, a gap is formed between the upper surface of the separating sheet 2 and the peripheral surface of the transport roller 3 and the peripheral surface of the separating roller 1.

As described above, the pressed state of the upper surface of the separating sheet 2 and the peripheral surface of the conveying roller 3 with respect to the peripheral surface of the separating roller 1 can be released only by swinging the holder 4 which is a single member. it can. Therefore, when the operation of the image forming apparatus 100 is stopped while the sheet is passing through the sheet feeding mechanism 10, when the sheet is removed from the sheet feeding mechanism 10, the operator holds the holder with one hand. 4 can be swung in the direction of arrow B, and the paper can be pulled out by the other hand, workability can be improved, and waste of resources due to damage of the paper can be prevented.

FIG. 5 is a schematic side view showing an arrangement state of the separating rollers, the separating sheets and the conveying rollers in the paper feeding mechanism. In the sheet feeding mechanism 10 of the present invention, the extension line La of the upper surface of the separating sheet 2 is divided by the line L1 connecting the rotation center of the separating roller 1 and the rotation center of the conveying roller 3 on the peripheral surface of the conveying roller 3. It is arranged to intersect with the separation sheet 2 side and an angle range of 90 ° which is a range on the separation roller 1 side divided by the diameter L2 of the transport roller 3 orthogonal to the line L1.

With this structure, the leading edge of the sheet passing between the peripheral surface of the separating roller 1 and the upper surface of the separating sheet 2 comes into contact with the peripheral surface of the conveying roller 3 in a range facing the sheet feeding direction. The paper can be reliably passed between the separating roller 1 and the transport roller 3, and the occurrence of paper folding at the leading end of the paper is prevented, so that the paper is stably formed in the image forming unit 2
Can be fed to 10.

The hardness of the conveying roller 3 is determined by the separating roller 1.
It is higher than the hardness of. Therefore, the conveying roller 3 is less likely to be deformed than the separating roller 1, and at the portion where the peripheral surface of the separating roller 1 and the peripheral surface of the conveying roller 3 are in pressure contact with each other, the peripheral surface of the separating roller 1 is the rotation axis of the separating roller 1. Deform so that it is convex to the side (inside). Therefore, at the pressure contact portion between the peripheral surface of the separating roller 1 and the peripheral surface of the conveying roller 3, a sheet conveying path is formed in a direction away from the peripheral surface of the separating roller 1.
The sheet passing between the separating roller 1 and the transport roller 3 is prevented from being wound around the peripheral surface of the separating roller 1, and the paper feeding mechanism 10 is provided.
The paper can be reliably fed from the.

In the above embodiment, the image forming apparatus has been described as an example of the sheet processing apparatus to which the sheet feeding mechanism according to the present invention is applied. However, each of the sheets stacked in the storage position is stored. On the other hand, the sheet feeding mechanism according to the present invention can be similarly applied to other sheet processing apparatuses that perform predetermined processing in the sheet processing unit.

[0040]

According to the present invention, the following effects can be obtained.

(1) A separation sheet whose upper surface is in pressure contact with the peripheral surface of the separation roller and a conveyance roller whose peripheral surface is in pressure contact with the peripheral surface of the separation roller are rotated on the downstream side of the conveyance roller in the paper feeding direction. By arranging them in this order from the upstream side to the downstream side in the paper feeding direction while being supported by a single swinging member that swings around an axis parallel to the axis, the separated sheets and the transport rollers swing. It operates integrally with the separating roller via the moving member, and passes between the peripheral surface of the separating roller and the upper surface of the separating sheet and between the peripheral surface of the separating roller and the peripheral surface of the conveying roller in this order. The separating function of the separation sheet and the conveyance roller can be made to act on the sheet to be processed in cooperation. Also,
By swinging a single swinging member, both the separation sheet and the transport roller can be separated or pressed against the peripheral surface of the separation roller at the same time, and when the sheet stopped in the sheet feeding mechanism is removed, The work can be easily performed by swinging the swing member with the other hand of the operator who holds the sheet to be pulled out by one hand.

As a result, the separation sheet and the transport roller are integrally operated with respect to the peripheral surface of the separation roller, and the cooperation of the two can prevent the paper feeding error and can prevent one worker from working. With this, the separation sheet and the transport roller can be separated from the separation roller, and the paper can be pulled out from the inside of the paper feed mechanism, so that waste of resources due to damage of the paper can be prevented.

(2) By individually setting the pressure contact forces of the upper surface of the separating sheet and the peripheral surface of the conveying roller with respect to the peripheral surface of the separating roller, when a plurality of sheets of paper are simultaneously fed from the paper feeding position, Depending on the respective separating functions, a separation sheet that separates the paper by applying frictional force from the flat upper surface to the lower surface and a transport roller that applies frictional force from the peripheral surface to the lower surface of the paper The pressure contact force can be set.

(3) By pressing the upper surface of the separating sheet against the peripheral surface of the separating roller with a biasing force larger than that of the peripheral surface of the conveying roller, the peripheral surface of the separating roller and the upper surface of the separating sheet are When the multiple sheets are fed simultaneously from the paper feed position, the multiple sheets of paper can move beyond the separation rollers to separate the separation rollers and the transport rollers. It is possible to reliably feed only the one sheet located at the uppermost position by reducing the frequency of reaching between and.

(4) By extending an extension line of the separating sheet in the paper feeding direction in a range facing the paper feeding direction on the peripheral surface of the conveying roller, the paper passing between the separating roller and the separating sheet is crossed. The leading edge of the sheet can be brought into contact with the peripheral surface of the conveying roller in a range facing the sheet feeding direction, and the sheet passing between the sheet separating sheet and the sheet separating sheet can be separated without causing a sheet break at the tip. It is possible to reliably feed the paper via the space between the sheet and the transport roller.

(5) By making it difficult for the conveying roller to be deformed as compared with the separating roller, the peripheral surface of the separating roller is attached to the rotation surface of the separating roller at the pressure contact portion between the peripheral surface of the separating roller and the peripheral surface of the conveying roller. The sheet can be deformed so as to be convex toward the side, and the sheet that has passed between the separating roller and the conveying roller can be prevented from being wound around the peripheral surface of the separating roller, and the sheet can be stably fed.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an image forming apparatus to which a sheet feeding mechanism according to an embodiment of the present invention is applied.

FIG. 2 is an external view showing the configuration of the main part of the paper feed mechanism of the present invention.

FIG. 3 is a schematic side view of a main part of the paper feeding mechanism.

FIG. 4 is a schematic side view illustrating an operation of a main part of the paper feeding mechanism.

FIG. 5 is a schematic side view showing an arrangement state of a separation roller, a separation sheet, and a conveyance roller in the paper feeding mechanism.

FIG. 6 is a side view showing a configuration of a main part of a conventional paper feeding mechanism.

[Explanation of symbols]

1-sorting roller 2-Handling sheet 3-Transfer roller 4-Holder (oscillating member) 5-Pickup roller 6,7-Spring (elastic member) 10-Paper feed mechanism 100-Image forming apparatus (sheet processing apparatus) 210-Image forming unit (paper processing unit) 2251-254-Paper feed tray (storage position)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuji Yamaji             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F-term (reference) 3F343 FA01 FA09 FB01 FC01 FC10                       GB01 GC01 GD01 JA19 JD04                       JD08 JD09 JD33 KB05

Claims (5)

[Claims] Claim: What is claimed is: 1. A sheet feeding mechanism, comprising: a separating roller that contacts an upper surface of a sheet fed from a storage position; and a separating sheet that presses a peripheral surface of the separating roller from below, in a sheet feeding direction. A conveying roller whose peripheral surface is in pressure contact with the peripheral surface of the separating roller is arranged on the downstream side of the sheet, and a single roller that swings around an axis parallel to the rotation axis of the conveying roller is provided downstream of the conveying roller in the paper feeding direction. A sheet feeding mechanism, characterized in that one swing member supports a separation sheet and a conveyance roller. 2. The sheet feeding mechanism according to claim 1, wherein the separating sheet and the conveying roller are biased toward the peripheral surface side of the separating roller by the elastic force of individual elastic members. 3. The urging force of the upper surface of the separating sheet with respect to the peripheral surface of the separating roller is set to be larger than the urging force of the peripheral surface of the conveying roller with respect to the peripheral surface of the separating roller. The paper feed mechanism described. 4. An extension line in the sheet feeding direction of the separation sheet is within a range on the separation sheet side, which is divided by a line connecting the rotation axis of the separation roller and the rotation axis of the conveyance roller on the peripheral surface of the conveyance roller. 4. The sheet feeding mechanism according to claim 1, wherein the sheet feeding mechanism intersects with a range on the separating roller side divided by a diameter of a conveying roller orthogonal to the line. 5. The sheet feeding mechanism according to claim 1, wherein the conveying roller has a hardness higher than that of the separating roller.