JPH10231033A - Sheet feeding and carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the passage length of a sheet carrying passage to carry sheets which are separated and fed from a mainbody-side feed cassette and an option-side feed cassette by a separating and feeding means formed with a frictional separation pad and a feed roller and reduce the number of carrying rollers arranged on the sheet carrying passage. SOLUTION: A sheet carrying passage 22 on the option side is provided to be extended from a sheet carrying passage 12 connected to a feed cassette 2 on the mainbody side and connected directly to a separation and feed position on the feed cassette 4 on the option side without a branch passage branching for every feed cassette 4. The sheet carrying passages 12, 22 are combined in one unit and no branch passage branching from the sheet carrying passage 22 for every feed cassette 4 is required, so that the total passage length of the sheet carrying passages 12, 22 can be greatly shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an image forming apparatus such as a facsimile apparatus, a printer, a copying machine, etc., and separates and feeds sheets stored in a sheet feeding cassette one by one. Paper feeder
The present invention relates to a transport device.

[0002]

2. Description of the Related Art Paper feed / conveyance devices applied to image forming apparatuses are roughly classified into two types: those having a separation feeding portion of a corner claw type and those having a separation feeding portion of a pad separation type.
Examples of a sheet feeding / conveying apparatus having a kind and a separating sheet feeding section of the corner claw type include, for example, JP-A-8-132605.
There are those described in Japanese Patent Application Laid-open No. In a sheet feeding / conveying apparatus having a separate sheet feeding section of the corner claw type, when a plurality of sheet cassettes are arranged, sheets fed from each sheet cassette are conveyed by one sheet conveying path. While it is easy to adopt a layout that makes it possible, a corner claw, a pick-up roller, a feed roller and a reverse roller, etc. are required, which increases the number of parts, and furthermore, the upstream side of the corner claw to reliably separate paper. Since it is necessary to secure a predetermined length or more from the pickup roller arranged in the feed roller to the feed roller and the reverse roller arranged downstream of the corner claw, there is a problem that the installation space of the apparatus becomes large, and generally, the image is It may not be suitable from the viewpoint of miniaturization and cost reduction of the forming apparatus.

On the other hand, in a sheet feeding / conveying apparatus having a separation sheet feeding unit of a pad separation type, sheets can be fed directly from a sheet cassette into a conveying path by a sheet feeding roller.
Also, unlike the corner claw method, which requires the position of the corner claw to be adjusted according to the paper size, there is no need to adjust the position of the paper feed roller and friction separation pad that constitute the separation paper feeding means. Therefore, in general, the image forming apparatus is efficient from the viewpoint of miniaturization and cost reduction.

FIG. 5 is a schematic view of a printer equipped with a conventional paper feeding / conveying device. Reference numeral 1 denotes an apparatus main body of the printer, and reference numeral 2 denotes a main body side detachably mounted on the apparatus main body 1. Paper feed cassettes 3 and 1 to multiple units (1 in the figure)
The optional paper feeding unit 3 is an optional paper feeding unit in which the optional paper feeding cassette 4 is detachably mounted. The optional paper feeding unit 3 is formed integrally with the apparatus main body 1 or
Alternatively, it is formed separately from the apparatus main body 1 and connected to the lower portion of the apparatus main body 1 so that a number of paper feed cassettes 4 corresponding to the type of paper P to be fed to the apparatus main body 1 can be mounted.
In the paper feed cassettes 2 and 4, reference numeral 5 denotes a case-shaped cassette main body for storing the paper P, and reference numeral 6 denotes a swingably supported bottom of the cassette main body 5, on which the paper P stored in the cassette main body 5 is placed. The sheet P placed on the bottom plate 6 is
It is urged upward by a pressure spring 6a disposed below the bottom plate 6. Reference numeral 7 denotes a friction separating pad disposed at the upper end of the cassette body 5 on the sheet feeding side, 8 denotes a pressure spring disposed below the friction separating pad 7 to urge the friction separating pad 7 upward, and 9 denotes a bottom plate 6. A paper feed roller 10 for pressing against both the leading end of the placed paper P and the friction separation pad 7;
Is a paper transport path on the option side which is connected to the paper feed cassette 4 which is constituted by a guide plate or the like and is mounted on the optional paper feed unit 3 and which extends into the apparatus main body 1;
Are a pair of conveying rollers arranged along.

In the apparatus main body 1, reference numeral 12 denotes a main body composed of a guide plate and the like, which is connected to the paper feed cassette 2 mounted on the apparatus main body 1 and extends to a paper discharge position via a transfer position. The paper transport path on the side 13 is a pair of registration rollers disposed on the paper transport path 12, and the optional paper transport path 10 on the upstream side of the registration roller pair 13 merges with the paper transport path 12 on the main body side. I have. Reference numeral 14 denotes an image forming unit that forms a toner image on a drum-shaped photoconductor 15 based on a known electrophotographic process, 16 denotes a transfer roller that transfers the toner image formed on the photoconductor 15 to paper P, and 17 denotes a toner image. Is a fixing unit for fixing the toner image by heating and pressing the sheet P onto which the image has been transferred, and a sheet discharging roller pair 18.

Next, a description will be given of a separating sheet feeding operation and an image forming operation in the printer configured as described above. When the paper P is separated and fed, any one of the paper feed cassettes 2 and 4 containing the paper P of a size adapted to the toner image on the photoconductor 15 is selected. A driving force is transmitted to one of the paper feeding rollers 9 corresponding to the selected paper feeding cassettes 2 and 4 via a clutch mechanism (not shown), and the driving force causes the paper feeding roller 9 to move to a predetermined predetermined position. Rotate by the amount of rotation of. As a result, the uppermost sheet P to which the sheet feeding roller 9 contacts is sent out in the sheet feeding direction or the sheet P
A plurality of sheets P including the uppermost sheet P due to frictional force between them
Is sent in the paper feeding direction, and the one or more sheets P are inserted between the paper feeding roller 9 and the friction separation pad 7.
At this time, when one sheet of paper P is sent in the sheet feeding direction by the sheet feeding roller 9, the single sheet of paper P is fed against the sheet feeding cassettes 2, 4 against the frictional force with the friction separation pad 7. When a plurality of sheets P are fed from inside to the sheet transport paths 10 and 12 and sent out in the sheet feeding direction by the sheet feeding roller 9, the uppermost sheet P is placed between the sheets P and in friction. The sheet transport paths 10, 12 from inside the sheet cassettes 2, 4 against the frictional force with the separation pad 7.
And the remaining paper P is fed by the frictional separation force between the friction separation pad 7 and the paper P until the uppermost paper P is fed to the paper transport paths 10 and 12.
4.

[0007] When the sheet feeding from the sheet feeding cassette 4 mounted on the optional sheet feeding unit 3 is selected in the above-described separated sheet feeding operation, the sheet P fed from the sheet feeding cassette 4 is transferred to the sheet feeding path. The sheet is conveyed by a pair of conveying rollers 11 along the path 10 and reaches a registration roller pair 13 via a junction with the sheet conveying path 12. When the paper feed cassette 2 on the main body side is selected, the paper P fed from the paper feed cassette 2 reaches the registration roller pair 13 along the paper transport path 12 by the transport force of the paper feed roller 9. I do.

The sheet P is conveyed by the pair of registration rollers 13 at the timing when the toner image on the photoconductor 15 moves to a predetermined position after the leading end thereof is once positioned by contacting the nip portion of the pair of registration rollers 13. Then, the toner image on the photoconductor 15 is transferred by the transfer roller 16. The sheet P is conveyed to the fixing device 17 and is heated and pressed to fix the toner image thereon, and is discharged to a discharge tray or the like outside the apparatus main body 1 by the discharge roller pair 18.

[0009]

In the above-described printer apparatus provided with a paper feeding / transporting apparatus for performing the paper separation and feeding by the paper separation means including the friction separation pad 7 and the paper feeding roller 9 as described above, The paper transport path 12 and the optional paper transport path 10 must be provided independently, and the optional paper transport path 10 is connected to the paper cassette 4 mounted on the optional paper feed unit 3. Fork 10
Since a must be provided, there arises a problem that the path length of the entirety of the paper transport paths 10 and 12 increases, and the number of transport roller pairs 11 arranged in the optional paper transport path 10 also increases.

It is an object of the present invention to solve the above-mentioned problem by separating paper fed from a main body paper cassette and an optional paper cassette by a separate paper feeding means comprising a friction separation pad and a paper feeding roller. It is an object of the present invention to provide a sheet feeding / transporting device that enables a reduction in the path length of a sheet conveying path to be conveyed and also enables a reduction in the number of conveying rollers disposed in the sheet conveying path.

[0011]

According to another aspect of the present invention, there is provided a sheet feeding / conveying apparatus according to the present invention, wherein the sheet feeding cassette is detachably mounted to an image forming apparatus main body. And an optional paper feed unit attached to the image forming apparatus main body and having one or more optional paper feed cassettes detachably mounted thereon, and a paper feed side end of the main body side and the optional paper feed cassette And a friction separation pad, which is disposed on the main body side and the option side paper feed cassette, and presses against the leading end of the paper stored in the paper feed cassette to separate and feed the paper in the paper feed cassette together with the friction separation pad. The paper feed roller constituting the means and the paper separated and fed from the main body side or the optional paper feed cassette by the separation paper feed means in a direction opposite to the paper feeding direction by the separate paper feed means. A sheet conveying means for conveying the sheet by rotating the sheet feeding roller corresponding to one of the selected sheet feeding cassettes to feed the sheet in the sheet feeding direction. And a sheet other than one sheet contacted by the sheet feed roller,
In a sheet feeding / conveying device that holds the sheet in a sheet cassette by frictional force of the friction separation pad, the sheet conveying unit includes:
A single paper transport path including a main body paper transport path connected to the main body paper cassette and an optional paper transport path extended from the main body paper transport path and connected to the optional paper feed cassette; And a transport roller for transporting the paper along the one paper transport path.

According to the first aspect of the present invention, the paper feeding means is extended from the main body paper feeding path connected to the main body paper feeding cassette and the main body paper feeding path. The entire paper transport path is constituted by one paper transport path comprising an optional paper transport path connected to the side paper cassette and a transport roller for transporting the paper along the one paper transport path. Path length can be greatly reduced.

Further, the paper feeding / conveying device according to claim 2 is
2. The sheet feeding / conveying device according to claim 1, wherein a roller surface formed of a circular curved surface and a cut surface formed of a non-circular curved surface obtained by cutting out the circular curved surface are formed on an outer peripheral surface of the sheet feeding roller,
When the paper feed roller is rotating, the roller surface faces the paper transport path, and when the paper feed roller is held at a predetermined standby phase, it is separated from the paper transport path by the cut surface.

According to a second aspect of the present invention, a roller surface having a circular curved surface and a cut surface having a non-circular curved surface formed by cutting out the circular curved surface are formed on the outer peripheral surface of the paper feed roller. When the paper feed roller is rotated, the roller surface faces the paper transport path, and when the paper feed roller is held at a predetermined standby phase, the paper face is separated from the paper transport path by the cut surface, so that the upstream paper feed is performed. The paper fed from the cassette can be prevented from contacting the downstream paper feed roller in the paper transport path.

Further, the paper feeding / conveying device according to claim 3 is
3. The sheet feeding and conveying device according to claim 2, wherein the sheet conveying means is provided on both sides of the sheet feeding roller, respectively.
As a transport roller, a driven roller rotatably supported by a rotation shaft of a paper feed roller and a driving roller for holding and transporting the sheet conveyed from the downstream side in contact with the driven roller together with the driven roller are provided. And

According to a third aspect of the present invention, there is provided a paper feeding / conveying device, wherein the paper conveying means is provided on both sides of the paper feeding roller, and the driven roller is rotatably supported by a rotation shaft of the paper feeding roller. By providing a driving roller as a conveying roller for holding and conveying the sheet conveyed from the downstream side in contact with the driven roller together with the driven roller, the number of conveying roller pairs disposed between the sheet feeding rollers is reduced, Alternatively, it is possible to eliminate the need, and to share the rotating shaft of the sheet feeding roller and the driven roller, and to simplify the mechanism for transmitting torque to the driving roller.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a main part of a printer device to which a paper feeding / conveying device according to a first embodiment of the present invention is applied. Members corresponding to those described with reference to FIG. The description is omitted here. Reference numeral 21 denotes a paper feed roller disposed at a mounting position of each of the paper feed cassette 2 on the main body side and the paper feed cassette 4 on the optional side. The paper feed roller 21 is mounted on the bottom plate 6 in the cassette main body 5. It is provided so as to be in pressure contact with both the leading end of the paper P and the friction separation pad 7. Also, 22
Is an optional paper transport path provided by extending the paper transport path 12 connected to the paper cassette 2 on the main body side. The paper transport path 22 is via a branch path branched for each paper cassette 4. Instead, it is directly connected to the separation paper feed position in the paper feed cassette 4 on the option side. Here, the separation sheet feeding position is defined as the friction separation pad 7 constituting the separation sheet feeding means.
This is a position where the paper P separated by the paper feed roller 21 is sent out of the paper feed cassettes 2 and 4 by the conveyance force of the paper feed roller 21. The paper transport paths 12 and 22 connected to each other are configured as a U-shaped reverse path as a whole, and the paper P separated and fed from the paper feed cassettes 2 and 4 is fed by a feed roller 21. The sheet is transported in a direction reverse to the sheet feeding direction.
This makes it possible to efficiently use the space in the apparatus main body 1, and thus facilitates downsizing of the apparatus main body 1.

Further, the outer peripheral surface of the paper feed roller 21 of the present embodiment includes a roller surface 21a formed of a circular curved surface and a cut surface 21b formed of a plane obtained by cutting the circular curved surface forming the roller surface 21a in a chord direction. The paper feed roller 21
Makes the roller surface 21a face the paper transport paths 12, 19 in the rotating state. Further, the sheet feeding roller 21 is controlled in phase in the rotation direction by a clutch mechanism (not shown) so as to be held at a predetermined standby phase during non-rotation when not performing separated sheet feeding,
The cut surface 21b is held in the illustrated standby phase.
To separate from the paper transport paths 12 and 22.

Next, a separate sheet feeding operation in the printer equipped with the sheet feeding / conveying device of the present embodiment will be described. At the time of separating and feeding the sheet P, any one of the sheets P containing the sheet P of a size adapted to the toner image on the photoconductor 15 is stored.
The paper feed cassettes 2 and 4 are selected. A driving force is transmitted to one of the sheet feeding rollers 21 corresponding to the selected sheet feeding cassettes 2 and 4 via a clutch mechanism, and the driving force causes the sheet feeding roller 21 to rotate by a predetermined rotation amount. Rotate. Here, as described above, the sheet feed roller 21 is held at a predetermined standby phase during non-rotation when the separation sheet feeding is not performed, so that the rotation amount of the sheet feeding roller 21 during the separation sheet feeding is an integer number of rotations (normally Must be one rotation).

When the paper feed roller 21 rotates, the uppermost sheet P contacting the roller surface 21a is sent out in the paper feeding direction, or a plurality of sheets including the uppermost sheet P are generated by frictional force between the sheets P. Is fed in the paper feeding direction, and the one or more sheets P are inserted between the roller surface 21 a of the paper feeding roller 21 and the friction separation pad 7. At this time, the roller surface 21a
When only one sheet P is sent out in the sheet feeding direction,
This one sheet of paper P is fed to the paper transport paths 12, 22 from inside the paper feed cassettes 2, 4 against the frictional force with the friction separating pad 7, and is also sent out in the paper feeding direction by the roller surface 21a. When there are a plurality of sheets of paper P, the topmost sheet of paper P is
The paper P is sent out of the paper feed cassettes 2 and 4 to the paper transport paths 10 and 12 against the frictional force between the paper feed cassettes 2 and 4 and the remaining paper P is transferred to the paper transport path 12 for the uppermost paper P. ,
Until the paper feeding to 22 is completed, friction separation pad 7 and paper P
The sheet is held in the sheet cassettes 2 and 4 by the frictional force therebetween.

When the sheet feeding from the sheet feeding cassette 4 mounted on the optional sheet feeding unit 3 is selected in the above-described separate sheet feeding operation, the sheet P fed from the sheet feeding cassette 4 is transported by the sheet feeding unit. The sheet is conveyed downstream along the path 22 by the conveying force of the sheet feeding roller 21 or the conveying force of the conveying roller pair 11. At this time, the feeding force can be applied to the paper P only when the paper feed roller 21 is holding the paper P together with the friction separation pad 7. Therefore, when the leading end of the sheet P cannot be conveyed to the pair of registration rollers 13 by the sheet feeding roller 21 alone,
Although it is necessary to arrange the transport roller pair 11 downstream of 21,
In the sheet feeding / conveying apparatus of the present embodiment, the sheet conveying paths 12 and 22 on the main body side and the option side are made into one, and a branch path that branches from the sheet conveying path 22 to the sheet feeding cassette 4 is unnecessary. Accordingly, the path lengths of the entire paper transport paths 12, 22 can be significantly reduced, so that the space occupied by the paper transport paths 12, 22 is reduced, and the paper transport paths 12, 22 are reduced.
It is possible to reduce the number of the conveying roller pairs 11 arranged in the device 22, and it is possible to reduce the size of the apparatus main body 1 and the cost of the apparatus.

The paper feed roller 21, which is held in the non-rotating state without performing the separate paper feed, is held at the illustrated standby phase and is separated from the paper transport paths 12, 22 by the cut surface 21b. Paper P fed from the upstream paper feed cassette 4
Can be prevented from contacting the paper feed roller 21 on the downstream side, so that the conveyance of the paper P fed from the optional paper feed cassette 4 in the paper conveyance paths 12 and 22 can be stabilized. Here, as shown in FIG.
In the case where 21b is not formed, the paper P fed from the upstream paper feed cassette 4 comes into contact with the downstream paper feed roller 21 and
The paper P may be caught on the roller surface 21a of the paper feed roller 21 having a high friction coefficient. If the paper P is caught on the roller surface 21a, the paper P buckles due to frictional resistance and a jam occurs, or the paper P rotates the paper feed roller 21 to cause misfeed. This causes the paper P fed from the cassette 4 to be unstable in the paper transport paths 12 and 22.

FIG. 2 is a structural view showing a main part of a paper feeding / conveying apparatus according to a second embodiment of the present invention, and FIG. 3 is an exploded perspective view for explaining the structure of a driven roller and a driving roller shown in FIG. The members corresponding to the members described with reference to FIGS. 1 and 5 are denoted by the same reference numerals, and description thereof will be omitted.
Reference numeral 31 denotes driven rollers provided on both sides of the paper feed roller 21, and the driven roller 31 is a rotating shaft of the paper feed roller 21.
33, and is rotatably supported by the rotating shaft 33. Numeral 34 denotes a driving roller which abuts on the driven roller 31.

As shown in FIG. 3, the rotating shaft of the paper feed roller 21
Both ends of the device 33 are connected to the apparatus main body 1 via bearing members 35, respectively.
Or, the frame portion of the optional paper feed unit 3 (not shown)
The gear 36 is mounted on one end of the rotating shaft 33. The gear 36 is one of the elements of a gear train (not shown) connected to the clutch mechanism. When the clutch mechanism is turned on and the conveyance motor (not shown) is turned on, the torque from the conveyance motor is applied to the paper feed roller 21. introduce. Here, the driven roller 31 is fixed at a position not in contact with the friction separation pad 7 in the axial direction, and a certain clearance is secured between the driven roller 31 and the sheet P against which the roller surface 21a of the sheet feeding roller 21 is pressed. As described above, the feed roller 21 is formed to have a smaller diameter than the radius of the feed roller 21.

Both ends of the rotating shaft 37 of the driving roller 34 are also disposed on the frame of the apparatus main body 1 or the optional sheet feeding unit 3 via bearing members 38, respectively. Have been. The gear 39 is one of the elements of a gear train (not shown) connected to the transport motor, and transmits torque from the transport motor to the drive roller 34 when the transport motor is turned on. The rotating shaft 37 supported in parallel with the rotating shaft 33 of the paper feed roller 21 is urged in the direction of the rotating shaft 33 by the contraction force of the pressure spring 40 connected to the bearing member 38, and The driving roller 34 comes into pressure contact with the driven roller 31 with a pressing force corresponding to the contraction force of the pressing spring 40.

According to the paper feeding / conveying apparatus of the second embodiment of the present invention configured as described above, the paper feeding cassettes 2, 4
The paper P fed from the paper feeding roller 21 is separated from the frictional separation pad 7 and the holding portion by the paper feeding roller 21, and the driven roller 31 and the driven roller 31 which are coaxial with the paper feeding roller 21 which separated and fed the paper.
The sheet P conveyed downstream along the sheet conveying paths 12 and 22 by the driving roller 34 pressed against the sheet 31 and further fed from the sheet feed cassette 4 on the upstream side is driven by the driven roller 31 disposed on the downstream side. And is conveyed by the drive roller 34. This reduces the number of transport roller pairs disposed between the paper feed roller 21 and between the paper feed roller 21 and the registration roller pair 13,
Or, it can be unnecessary, and the rotating shaft 33 of the sheet feeding roller 21 and the driven roller 31 can be shared, and the driving roller
Since the gear train serving as the torque transmission mechanism to the motor 34 can be simplified, the size of the apparatus body 1 and the cost of the apparatus can be further reduced.

[0027]

As described above, according to the first aspect of the present invention,
According to the sheet feeding / conveying device described above, the sheet conveying means is connected to the main unit side sheet conveying path connected to the main unit side sheet feeding cassette and the optional side sheet feeding cassette extended from the main unit side sheet conveying path. 1 consisting of the optional paper transport path
Since the paper transport path and the transport rollers for transporting the paper along the one paper transport path are configured, the path length of the entire paper transport path can be significantly reduced. The space occupied by the path can be reduced, and the number of transport rollers arranged in the paper transport path can be reduced, so that the apparatus main body can be downsized and the apparatus cost can be reduced.

According to a second aspect of the present invention, in the sheet feeding / conveying apparatus according to the first aspect, a roller surface having a circular curved surface and a circular curved surface are cut out on the outer peripheral surface of the sheet feeding roller. Forming a cut surface consisting of a non-circular curved surface, the paper feed roller faces the roller surface in the paper transport path in a rotating state, and from the paper transport path by the cut surface in a state of being held in a standby phase. By separating, the paper fed from the upstream paper feed cassette can be prevented from coming into contact with the downstream paper feed roller in the paper transport path. The conveyance in the conveyance path can be stabilized.

According to a third aspect of the present invention, there is provided the sheet feeding / conveying apparatus according to the second aspect, wherein the sheet conveying means is provided on both sides of the sheet feeding roller. A driven roller rotatably supported by a rotation shaft and a driving roller for holding and conveying the sheet conveyed from the downstream side while being in contact with the driven roller as a conveying roller are provided as conveying rollers, so that the distance between the sheet feeding rollers and The number of transport rollers disposed between the feed roller and the registration roller pair can be reduced or made unnecessary, and the rotary shaft of the feed roller and the driven roller can be shared, and torque is transmitted to the drive roller. Since the mechanism can be simplified, it is possible to further reduce the size of the apparatus main body and reduce the apparatus cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a main part of a printer device to which a sheet feeding / conveying device according to a first embodiment of the present invention is applied.

FIG. 2 is a configuration diagram illustrating a main part of a sheet feeding / conveying device according to a second embodiment of the present invention.

FIG. 3 is an exploded perspective view illustrating a configuration of a driven roller and a driving roller illustrated in FIG. 2;

4 is an operation explanatory diagram of a sheet feeding roller without a cut surface for describing an effect of a cut surface provided in the sheet feeding roller shown in FIG. 2;

FIG. 5 is a configuration diagram schematically showing a printer device provided with a conventional paper feed / conveyance device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device main body, 2, 4 ... Paper feed cassette, 3 ... Optional paper feed unit, 7 ... Friction separation pad, 12, 22 ...
Paper transport path, 21: paper feed roller, 21a: roller surface, 2
1b: cut surface, 31: driven roller, 33, 37: rotating shaft,
34: drive roller, P: paper.

Claims (3)

[Claims] 1. A main body side paper cassette detachably mounted to an image forming apparatus main body, and one or more optional side paper cassettes attached to the image forming apparatus main body and detachably mounted. An optional paper feeding unit, friction separating pads respectively disposed at the paper feeding side ends of the main body side and the optional side paper feeding cassette, and a leading end of the paper stored in the main body side and the optional side paper feeding cassette And a paper feed roller which constitutes a separation paper feeding means for separating and feeding the paper in the paper feeding cassette together with the friction separation pad, and separated from the main body side or the inside of the optional paper feeding cassette by the separation paper feeding means. Paper feeding means for conveying the fed paper in a direction opposite to the paper feeding direction by the separation paper feeding means; Rotates the paper feed roller corresponding to the selected one paper feed cassette to feed the paper in the paper feed direction, and separates the paper other than the one paper contacted by the paper feed roller into the frictionally separated paper. In a paper feed / conveyance device that holds a sheet in a paper cassette by frictional force of a pad, the paper conveyance unit is extended from a main body side paper conveyance path connected to the main body side paper supply cassette and the main body side paper conveyance path. A single paper transport path comprising an optional paper transport path connected to the optional paper cassette;
A sheet feeding / conveying device comprising a conveying roller for conveying a sheet along a sheet conveying path of a book. 2. A roller surface comprising a circular curved surface and a cut surface comprising a non-circular curved surface formed by cutting out the circular curved surface are formed on an outer peripheral surface of the paper feeding roller, and the roller surface is formed when the paper supplying roller is rotated. 2. The sheet feeding / conveying apparatus according to claim 1, wherein the sheet is separated from the sheet conveying path by the cut surface when the sheet is held at a predetermined standby phase in the sheet conveying path. 3. The paper transport means is provided on both sides of the paper feed roller, and is driven by a driven roller rotatably supported by a rotation shaft of the paper feed roller, and is transported from a downstream side in contact with the driven roller. 3. The sheet feeding / conveying apparatus according to claim 2, further comprising a driving roller for nipping and conveying the fed sheet together with a driven roller as the conveying roller.