JP2001088955A - Paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a feed roller from making contact with a recording paper or separation member more than it is required and to prevent a fixed position (same position) of the feed roller from being intensively worn to attain the improvement in durability and the stabilization of feeding performance and separating performance. SOLUTION: The feed roller 4 side is connected to a roller shaft 6 side through a one-way rotation transmitting means 26 of ratchet structure. When the roller shaft 6 rotates and a shaft pin 61 presses a tapered surface 32b, a ratchet member 32 is moved and meshed to transmit a rotating driving force to the feed roller 4. The center of a collar 10 is shifted from the center of the roller shaft 6 in the state where a pair of carrying rollers 14 carries a recording paper 34 to bring the collar 10 into contact with the recording paper 34 and a separation pad 12, and the feed roller 4 is freely rotated without making contact with the recording paper 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder applied to an image forming apparatus such as a copying machine, a printer, a facsimile, and the like.

[0002]

2. Description of the Related Art As shown in FIG. 5, for example, a conventional paper feeding apparatus includes a columnar paper feeding roller 100, a roller shaft 102 for supporting the paper feeding roller 100, and a separation pad 104 as a separation member. , A holder 106 for holding the separation pad 104, and a pair of transport rollers 108 provided on the downstream side of the separation pad 104. A plurality of recording papers 112 are stacked on a bottom plate 110 of the paper feed cassette. One end of the bottom plate 110 is rotatably attached to the cassette body, and the other end is urged toward the paper feed roller 100. Thus, the recording paper 112 is in contact with the paper feed roller 100 at a predetermined paper feed pressure Pp. Holder 10
6 is also urged toward the paper feed roller 100, and the separation pad 104 is in contact with the paper feed roller 100 at a predetermined separation pressure Ps.

The roller shaft 102 is driven by driving means (not shown).
Is rotated, the paper feed roller 100 rotates, and the recording paper 112 is fed. At this time, a plurality of recording papers 11
When 2 is fed, the recording papers 112 are separated at the nip portion between the separation pad 104 and the paper feed roller 100 and are fed one by one toward the transport roller pair 108.

[0004] Originally, the recording paper 112 is
If the paper feed roller 100 is conveyed, the subsequent rotation of the paper feed roller 100 is unnecessary. However, when the cylindrical paper feed roller 100 is used, while the recording paper 112 is being conveyed, the paper feed roller 100 rotates while the recording paper 112 is sandwiched between the paper and the separation pad 104. For this reason, abrasion is fast and a large amount of paper dust is generated, so that the surface of the paper feed roller 100 or the surface of the separation pad 104 cannot maintain the initial performance for a long period of time, and the paper feed performance and the separation performance deteriorate early. was there.

To cope with this problem, Japanese Patent Application Laid-Open No. 10-29
Japanese Patent Application Laid-Open No. 7778 discloses a paper feeder using a half-moon-shaped paper feed roller lacking a part of an arc. As shown in FIG. 6, on both sides of a half-moon-shaped paper feeding roller 114, eccentric collar bearings 116 are fixed to the roller shaft 102, and a collar 118 is rotatably supported by each collar bearing 116. are doing. The recording paper conveying surface of the paper feeding roller 114 is substantially moved to the conveying roller pair 108 by the recording paper 11.
In this case, the upper surface of the recording paper 112 is pressed by the collar 118 in the initial state.

In the initial state, the collar 118 is in contact with the upper surface of the recording paper 112 and the separation pad 104.
When the roller shaft 102 rotates, the collar 118 does not rotate due to contact friction, but is displaced (revolves) due to the eccentricity of the collar bearing 116, and moves away from the recording paper 112 and the separation pad 104 as the paper feed roller 114 rotates. As the collar 118 moves away, the paper feed roller 1
14 comes into contact with the recording paper 112 and the separation pad 104, and paper is fed. By the way, in a configuration using a cylindrical feed roller and a collar that is not eccentric, the outer diameter of the collar is usually slightly smaller than the outer diameter of the feed roller. When the paper is started, the vertical position of the leading end of the recording paper and the vertical position of the separation pad vary greatly, and the recording paper may not be conveyed normally. Conversely, if the difference in outer diameter is reduced, the flatness and dimensions of the bottom plate
If the bottom plate is tilted in the vertical direction with respect to the axial direction of the roller shaft, the recording paper may not be able to stay on one side of the rubber layer of the paper feed roller and normal paper feeding may not be possible. There is. On the other hand, in the device described in JP-A-10-297778, the color 11
8 and the dimensional difference between the feed roller 114 and the feed roller 114 are small, and when the feed roller 114 rotates and comes into contact with the recording paper 112, the dimensional difference between the outer diameter of the collar 118 and the outer diameter of the feed roller 114 is obtained. The difference is increasing.

[0007]

Problems to be Solved by the Invention Japanese Patent Laid-Open No. Hei 10-2977
According to the technology described in Japanese Patent Application Publication No.
4, the load is applied to the paper feed roller 114 most when the contact with the recording paper 112 is started, and the contact start portion is the same place on all the recording papers 112, so that the rubber surface of that portion is cut most. . Accordingly, the diameter of only the contact start portion of the paper feed roller 114 becomes smaller with time, the friction coefficient is reduced, and the paper feed performance is reduced. When the paper feed roller 114 starts rotating with the leading end of the recording paper 112 remaining on the separation pad 104, and when the paper supply roller 114 conveys the recording paper 112 with the collar 118 in contact with the separation pad 104, Since the leading end of the recording paper 112 is pressed by the collar 118, the leading end of the recording paper 112 cannot move forward, and buckling may occur in the case of thin paper.

Further, in an environment with high humidity, the top surface of the recording paper 112 is wavy even in the initial state,
When a portion having high waving contacts the sheet feeding roller 114 in a state where the sheet contacts the recording sheet 112 and the roller shaft 102 starts rotating, the recording sheet 112 may be skewed.
Further, in the conventional configuration, the contact between the paper feed roller and the separation pad is unavoidable, and the contact time is long, so that there is a problem of stick-slip noise and a large load torque to the drive source.

Therefore, an object of the present invention is to provide a sheet feeding device capable of solving the above-mentioned problems.

[0010]

Means for Solving the Problems In order to solve the above problems,
According to the first aspect of the present invention, a paper feed roller, a roller shaft rotatably supported by the paper feed roller, and the roller shaft provided on both sides of the paper feed roller so as to be rotatable in synchronization with the roller shaft. Collar bearings, a collar rotatably supported by each of these collar bearings, a separation member that abuts the paper feed roller, and a pair of transport rollers provided downstream of the separation member in the paper feed direction, A paper feeder for separating the recording paper one by one by feeding the recording paper fed by the paper feeding roller between the paper feeding roller and the separating member and feeding the recording paper to the pair of transport rollers, In a state where the paper feed roller and the collar have a circular cross section, and the transport roller pair is transporting the recording paper, the center of the color is eccentric with respect to the center of the roller shaft, and the color is the recording paper and the color. Contacts the separation member, One, the paper feed roller is not in contact with the recording paper, and employs a configuration that.

According to a second aspect of the present invention, in the configuration of the first aspect, the paper feed roller and the roller shaft are connected by one-way rotation transmitting means for transmitting a rotational force in only one direction, and the roller shaft rotates. In a state in which the recording paper is stopped and the recording paper is being conveyed by the conveyance roller pair, the paper feed roller and the color rotate together.

According to a third aspect of the present invention, in the configuration according to the second aspect, a friction member is provided between the paper feed roller and the collar, and the friction member rotates with the friction member. The configuration is adopted.

According to the fourth aspect of the present invention, the second or third aspect is provided.
In the configuration described above, the one-way rotation transmission means has a ratchet-shaped meshing configuration.

According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the ratchet-shaped portion on the roller shaft side is formed as a separate member, and after the roller shaft has rotated a predetermined amount, the ratchet member has It is configured to engage with the roller side.

According to a sixth aspect of the present invention, in the configuration according to the fifth aspect, after the rotation of the roller shaft and the color is started, the rotation of the roller shaft is performed simultaneously with or after the paper feed roller contacts the recording paper. Is set to be transmitted to the paper feed roller.

According to a seventh aspect of the present invention, in the configuration of the fifth aspect, after the start of rotation of the roller shaft and the collar, at a timing when the leading edge of the recording paper does not reach a contact point between the collar and the separation member. The predetermined amount is set so that the rotation of the roller shaft is transmitted to the paper feed roller.

According to the eighth aspect of the present invention, the first, second, and third aspects of the present invention are provided.
In the configuration described in 3, 4, 5, 6, or 7, the friction coefficient between the collar and the collar bearing is smaller than the friction coefficient between the collar and the recording paper.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the paper feeding device 2 according to the present embodiment includes a paper feeding roller 4, a roller shaft 6 to which the paper feeding roller 4 is fixed, and a roller shaft 6 on both axial sides of the paper feeding roller 4.
, A collar 10 having a circular cross section rotatably supported by each of the collar bearings 8, and a separation member serving as a separation member that abuts the paper feed roller 4 at a predetermined paper feed pressure. It has a pad 12 and a pair of transport rollers 14 provided downstream of the separation pad 12 in the sheet feeding direction. The collar bearing 8 is eccentric with respect to the roller shaft 6.
The paper feed roller 4 (substantially the roller shaft 6) and the transport roller pair 14 are driven by a drive source (not shown).

The paper feed roller 4 has a cylindrical roller base 1.
6, a cylindrical rubber layer 18 provided on the outer peripheral surface of the roller base 16, and spacers 20 and 22 for fixing the roller base 16 to the roller shaft 6. On the surface of the rubber layer 18, a number of axially extending ridges 18a are formed to prevent slippage during paper feeding. An annular elastic member 24 as a friction member is disposed between the collar 10 and the roller base 16 without being fixed to any of them. Reference symbol C indicates the rotation center of the paper feed roller 4.

On the spacer 22 side, the paper feed roller 4 and the roller shaft 6 are connected by a one-way rotation transmitting means 26 for transmitting a rotational force in only one direction. The one-way rotation transmitting means 26 is formed by dividing the cylindrical portion 28 of the roller shaft 6, and includes a ratchet 30 as a tooth on the paper feed roller 4 side, a ratchet member 32 on the roller shaft 6 side, and a ratchet 30. A shaft pin 6a for driving the member 32 is provided. The shaft pin 6a is formed integrally with the roller shaft 6.
The ratchet member 32 is formed as a separate member from the roller shaft 6, and is accommodated in the roller shaft 6 so as to be slidable in the axial direction of the paper feed roller 4. The ratchet member 32 includes a shaft pin 6a.
Is formed, and a tapered surface 32b whose axial width changes is formed.

When the roller shaft 6 is rotationally driven by driving means (not shown) and the shaft pin 6a moves in the rotational direction through the notch 32a, the shaft pin 6a moves the tapered surface 32b from a wide portion to a narrow portion of the gap. Therefore, the ratchet member 32 gradually moves to the left in the drawing, and finally, the ratchet 30 and the ratchet member 32 on the side of the paper feed roller 4 mesh with each other, and the rotational force is transmitted to the paper feed roller 4. FIG.
As shown in (a), the moving range (predetermined amount) of the shaft pin 6a in the notch 32a is called a gap angle. In FIG. 1A, the arc 32a is formed by the notch 3
The range of 2a is shown. Reference symbol S indicates a boundary point between the color 10 and the paper feed roller 4. When the ratchet 30 and the ratchet member 32 are engaged with each other, the roller shaft 6 stops, and the engagement is released even when the paper feed roller 4 rotates.

The rotation of the collar 10 is transmitted to the paper feed roller 4 by the frictional force generated by the pressing deformation of the elastic members 24 arranged on both sides of the paper feed roller 4. However,
The rotational force due to the pressing deformation of the elastic member 24 is
If the paper feed roller 4 comes into contact with the recording paper 34 in this state, a slip occurs between the collar 10 and the elastic member 24 or between the paper feed roller 4 and the elastic member 24, and the paper feed roller 4 The moment the sheet 4 comes into contact with the recording paper 34, the sheet feeding roller 4 stops.

The separation pad 12 is held by a holder 36, and comes into contact with the paper feed roller 4 or the collar 10 at a predetermined separation pressure. A plurality of recording papers 34 stored in a paper feed cassette (not shown) in a stacked state are also in contact with the paper feed roller 4 or the collar 10 at a predetermined paper feed pressure.

Next, the paper feeding operation of the paper feeding device 2 will be described.
Rotation control means (not shown) is connected to the roller shaft 6, and when the roller shaft 6 makes one rotation, driving from a drive source (not shown) is shut off and the roller shaft 6 is stopped. I have. The state where the roller shaft 6 is stopped is the initial state or the standby state shown in FIG. In this state, the shaft pin 6a of the roller shaft 6 is connected to the ratchet member 32.
Is located on the wide side of the gap between the tapered surface 32b of the notch portion 32a and the teeth of the ratchet member 32 and the feed roller 4
The ratchet 30 on the side is disengaged from the ratchet 30, and the drive by the roller shaft 6 is released.

Since the center of the collar 10 is eccentric with respect to the rotation center of the roller shaft 6 in the direction in which the collar 10 comes into contact with the recording paper 34 and the separation pad 12, the separation pad 12 and the collar 10 are not shown in FIG. Contact is made at a contact point A shown in FIG. For this reason, when the paper feed roller 4 conveys the recording paper 34, the leading end of the next recording paper 34 may reach the contact point A due to friction between the conveyed recording paper 34 and the next recording paper 34. is there. In the initial state or the standby state, the color 10
Is in contact with the upper surface of the recording paper 34, and the paper feed roller 4 is
And is separated from the separation pad 12.

From this initial state or standby state, driving is started by a driving source (not shown), and the roller shaft 6 is moved by a rotation control means (not shown) in the direction of arrow N (the rotation direction of the sheet feeding roller 4) shown in FIG. Starts rotating. At this time, the entire collar 10 starts rotating and moving around the roller shaft 6. However, since the collar 10 comes into contact with the separation pad 12 and the collar 10 itself is restrained from rotating around the collar bearing 8, the collar 10 is pressed. The rotational driving force due to the frictional force caused by pressing and deforming the elastic member 24 of the roller 10 slides between the collar 10 and the elastic member 24 or between the paper feed roller 4 and the elastic member 24, and the collar 10 itself does not rotate and the roller shaft 6 does not rotate. Is revolved around the center by the amount of eccentricity. Also, the roller shaft 6
Shaft pin 6a is a notch 32a of the ratchet member 32.
During the movement of the collar 10, the feed roller 4 stops during the revolving movement of the collar 10 because the engagement between the feed roller 4 side and the ratchet member 32 does not occur during the movement of the roller 10, and the driving force of the roller shaft 6 is not transmitted. It is in a state of having done.

When the shaft pin 6a moves the notch 32a of the ratchet member 32 from the wide side to the narrow side of the gap of the tapered surface 32b, the shaft pin 6a presses the tapered surface 32b. As shown in FIG. 2, the shaft pin 6a moved by the gap angle so as to approach the ratchet 30 on the fourth side, and came into contact with the narrow end surface of the tapered surface 32b of the cutout portion 32a. At this time, the ratchet 30 on the paper feed roller 4 and the ratchet member 32 on the roller shaft 6 mesh with each other. At the moment when the shaft pin 6a comes into contact with the narrow end face of the tapered surface 32b of the notch 32a, the rotation driving force from the roller shaft 6 is transmitted to the paper feed roller 4, and the paper feed roller 4 starts rotating.

The gap angle is set so that the recording paper 34 is conveyed by the paper supply roller 4 in a state where the boundary point S between the paper supply roller 4 and the color 10 has passed the contact point K with the recording paper 34. . That is, the gap angle is set such that the recording paper 34 is conveyed by the paper supply roller 4 in a state where the color 10 is separated from the recording paper 34 and the paper supply roller 4 is in contact with the recording paper 34. 2A, the collar 10 revolves around the center of the roller shaft 6 by the amount of eccentricity, thereby causing the separation pad 12 and the collar 1 to move.
The contact point A of 0 is downstream from the leading end position (the contact point A in FIG. 1A) when the next recording paper 34 is conveyed to the contact point between the separation pad 12 and the collar 10 due to friction between the papers. Has moved to the side. That is, before the leading end of the recording paper 34 reaches the contact point A between the separation pad 12 and the color 10, the color 10
The gap angle is set so as to pass through the separation pad 12. For this reason, it is prevented that the recording paper 34 is conveyed by the paper feed roller 4 while the leading end of the recording paper 34 is pressed by the collar 10.

When the leading end of the recording paper 34 reaches the nip portion of the transport roller pair 14 and the paper feed roller 4 is further rotated, FIG.
As shown in (1), the boundary point between the paper feed roller 4 and the color 10 passes through the contact point with the recording paper 34 again. At this moment, the paper feed roller 4 is separated from the recording paper 34 and the conveyance of the recording paper 34 is stopped. When the collar 10 reaches the position of the initial state or the standby state and the roller shaft 6 makes one rotation, the roller shaft 6 is stopped by rotation control means (not shown). Then, as shown in FIG. 4, the recording paper 34 is transported by the transport roller pair 14. Since the recording paper 34 and the collar 10 are in contact with each other, the collar 10 is in the initial state or the standby state.
Spins around and rotates around. At this time, color 10
The rotational driving force due to the frictional force caused by pressing and deforming the elastic member 24 is transmitted to the paper feed roller 4 and
Rotates together with the recording paper 34.

When the paper feed roller 4 rotates along with the rotation of the collar 10, the ratchet member 32 moves in the direction of the arrow R, and the ratchet 30 on the paper feed roller 4 and the ratchet member 32 on the roller shaft 6 disengage. At this time, the rotational force of the paper feed roller 4 is not transmitted to the roller shaft 6, and the roller shaft 6 remains stopped. In this embodiment, the color 1
The friction coefficient between 0 and the color bearing 8 is set smaller than the friction coefficient between the color 10 and the recording paper 34. For this reason,
When the conveying roller pair 14 conveys the recording paper 34 with the roller shaft 6 stopped, the collar 10 surely rotates and rotates around the collar bearing 8.

At the moment when the rear end of the recording paper 34 passes through the contact point A between the separation pad 12 and the collar 10 shown in FIG.
The rotation of 0 stops, and the state becomes the initial state or the standby state shown in FIG. At this time, the leading end of the recording paper 34 following the recording paper 34 being conveyed by the conveying roller pair 14 reaches the contact point A between the separation pad 12 and the collar 10 shown in FIG. There are cases where the separation pad 1
2, the separation pad 12 and the color 10
Is not conveyed before the contact point A.

The present invention is not limited to the configuration shown in the above embodiment. For example, the elastic member 24 of the collar 10
Is configured to rotate the paper feed roller 4 by the rotational driving force due to the frictional force caused by pressing and deforming the roller. However, the configuration may be such that the rotational driving force of the transport roller pair 14 is transmitted to the paper feed roller 4 and rotated. . Further, the one-way rotation transmitting means 26 may employ a one-way clutch instead of the ratchet configuration.

[0033]

According to the first aspect of the present invention, in the state where the paper feed roller and the collar have a circular cross section and the transport roller pair is transporting the recording paper, the center of the collar is the center of the roller shaft. Since the collar is eccentric with respect to the recording paper and the separating member, and the paper feed roller is configured not to contact the recording paper, the contact time between the paper feeding roller and the separating member is reduced or eliminated. The wear of the feed roller can be reduced,
Durability and reliability can be improved. In addition, the stick-slip noise generated when the paper feed roller comes into contact with the separating member and the load torque on the drive source are reduced or eliminated. Further, when the contact of the paper feed roller with the recording paper starts, the scraping of the transfer surface (rubber surface) of the paper feed roller near the boundary between the color and the paper feed roller that most applies a load is not fixed to one place. Since the abrasion is performed uniformly over the entire circumference, the durability can be further improved, and the paper feeding performance and the separation performance can be stabilized.

According to the second aspect of the present invention, in the state where the paper feed roller and the roller shaft are connected by the one-way rotation transmitting means, and the roller shaft stops rotating and the recording paper is conveyed by the conveyance roller pair, Since the paper feed roller and the collar are configured to rotate together, it is possible to prevent the shaving of the conveyance surface of the paper feed roller from being fixed to one place with a simple configuration.

According to the third aspect of the present invention, since the paper feed roller and the collar are configured to rotate together with the frictional force of the friction member, the conveying surface of the paper feed roller can be scraped in one place with a simple configuration. It can be prevented from being fixed.

According to the fourth and fifth aspects of the present invention, since the one-way rotation transmitting means has a ratchet-shaped meshing structure, the conveying surface of the paper feed roller can be scraped off at one position with a simple structure. Can be prevented from being fixed.

According to the present invention, the rotation of the roller shaft is transmitted to the paper feed roller simultaneously with or after the start of rotation of the roller shaft and the color when the paper feed roller comes into contact with the recording paper. Therefore, even if the vertical position of the leading edge of the recording paper and the vertical position of the separating member fluctuate greatly at the start of paper feeding due to a large dimensional difference between the outer diameter of the color and the outer diameter of the paper feed roller, the color can be removed from the recording paper. When the recording paper is separated, the recording paper is surely brought into contact with the paper feed roller, and at the same time, the driving force is transmitted to the paper feed roller and rotation starts, so that the recording paper can be transported reliably.
Conversely, when the difference in outer diameter is small and the bottom plate of the paper feed cassette is tilted up and down with respect to the axial direction of the roller shaft due to variations in the flatness and dimensions of the bottom plate of the paper feed cassette, Even when the recording paper only partially touches one side of the layer, or where the upper surface of the recording paper is wavy and the color is in contact with the recording paper in a high-humidity environment, the high wavy area is the paper feed roller. Even when the roller shaft contacts, the paper feed roller does not rotate, the color separates from the recording paper, and the recording paper makes reliable contact with the paper feed roller, and at the same time, the drive is transmitted to the paper feed roller and rotation starts. Therefore, it is possible to prevent the skew of the recording paper from occurring due to the waving of the upper surface of the recording paper.

According to the present invention, the rotation of the roller shaft is transmitted to the feed roller at a timing at which the leading end of the recording paper does not reach the contact point between the collar and the separation member after the rotation of the roller shaft and the color is started. As a result, even when the leading edge of the recording paper remains on the separating member, the leading edge of the recording paper is not pressed by the collar, and buckling with thin paper can be prevented.

According to the present invention, the friction coefficient between the collar and the color bearing is made smaller than the friction coefficient between the collar and the recording paper, so that the pair of conveying rollers transports the recording paper with the roller shaft stopped. Reliable rotation of the collar when transporting,
It is possible to obtain entrainment, and it is possible to prevent rubbing marks due to color from remaining on the recording paper.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a paper feeding device according to an embodiment of the present invention in an initial state or a standby state, where (a) is a schematic front view,
(B) is a schematic sectional view.

FIGS. 2A and 2B are schematic diagrams when a rotational driving force is transmitted from a roller shaft to a paper feed roller, where FIG. 2A is a schematic front view and FIG. 2B is a schematic cross-sectional view.

FIGS. 3A and 3B are schematic diagrams illustrating a state in which a recording sheet is being conveyed by a paper feed roller. FIG. 3A is a schematic front view, and FIG.

FIGS. 4A and 4B are schematic diagrams illustrating a state in which a recording sheet is conveyed by a pair of conveying rollers, and a paper feed roller is separated from the recording sheet and a color is rotating; FIG. 4A is a schematic front view, and FIG. It is an outline sectional view.

FIG. 5 is a schematic front view of a conventional sheet feeding device.

FIG. 6 is a schematic front view of another conventional sheet feeding device.

[Explanation of symbols]

 Reference Signs List 4 feed roller 6 roller shaft 8 collar bearing 10 collar 12 separation pad as separation member 14 pair of conveyance rollers 26 one-way rotation transmission means 24 elastic member as friction member 32 ratchet member A contact point

Claims (8)

[Claims] A feed roller; a roller shaft rotatably supported by the feed roller; and a collar bearing provided on both sides of the feed roller so as to be rotatable in synchronization with the roller shaft. And a collar rotatably supported by each of the collar bearings, a separation member abutting on the paper feed roller, and a pair of transport rollers provided downstream of the separation member in the paper feed direction. A sheet feeding device for separating the recording sheet one by one by feeding the recording sheet fed by a roller between the sheet feeding roller and the separating member and feeding the sheet to the pair of conveying rollers; And the collar has a circular cross section, and in a state in which the transport roller pair is transporting the recording paper, the center of the collar is eccentric with respect to the center of the roller shaft, and the collar is in contact with the recording paper and the separation member. Contact and A paper feeding device, wherein the paper roller does not contact the recording paper. 2. The sheet feeding device according to claim 1, wherein the sheet feeding roller and the roller shaft are connected by a one-way rotation transmitting means for transmitting a rotational force in only one direction, and the roller shaft stops rotating when the roller shaft stops rotating. A paper feeding device, wherein the paper feed roller and the color rotate together when the recording paper is being transported by a transport roller pair. 3. The paper feeding device according to claim 2, wherein a friction member is provided between the paper feeding roller and the collar, and the friction member rotates with the friction member. Paper feeder. 4. The paper feeder according to claim 2, wherein said one-way rotation transmitting means has a ratchet-shaped meshing structure. 5. The paper feeding device according to claim 4, wherein the ratchet-shaped portion on the roller shaft side is formed as a separate member, and the ratchet member meshes with the paper feeding roller side after the roller shaft rotates a predetermined amount. A sheet feeding device, characterized in that: 6. The paper feeding device according to claim 5, wherein after the rotation of the roller shaft and the color is started, the rotation of the roller shaft is performed simultaneously with or after the paper feeding roller contacts the recording paper. A sheet feeding device wherein the predetermined amount is set so as to be transmitted to a roller. 7. The paper feeding device according to claim 5, wherein after the rotation of the roller shaft and the color starts, the leading end of the recording paper does not reach a contact point between the color and the separation member. A sheet feeding device, wherein the predetermined amount is set so that rotation is transmitted to the sheet feeding roller. 8. The paper feeder according to claim 1, wherein the coefficient of friction between the collar and the color bearing is smaller than the coefficient of friction between the color and the recording paper. A sheet feeding device characterized by the following.