JPH05278885A - Friction separating paper feeding device and friction separating paper feeding method - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent double feeding or non-feeding of paper when the paper is fed using the paper feed roller and the friction separation pad. [Structure] A plurality of stacked sheets of paper 1
And a friction separating pad 1 which is located downstream in the conveying direction of the sheet 1 and elastically abuts on the outer peripheral surface of the sheet feeding roller 5.
And a tilt angle changing means for moving the friction separating pad 14 in a direction for changing the tilt angle of the friction separating pad 14 with respect to the conveying direction of the sheet 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction separating and feeding apparatus and a friction separating and feeding method for separating stacked sheets and feeding them one by one.

[0002]

2. Description of the Related Art Conventionally, in PPCs (plain paper copying machines), facsimiles, printers, etc., it is necessary to separate the sheets set in a stacked state and feed them one by one. A large number of friction separation paper feeding methods that utilize the frictional force of a friction separation member are used for separating and feeding such paper. Among them, the method that uses a friction separation pad as the friction separation member is the most popular. ing.

As shown in FIG. 4, a conventional friction separating / feeding apparatus using a friction separating pad is arranged above a plurality of sheets 1 stacked in a sheet feeding cassette (not shown) or the like. And a friction separating pad 3 which is located downstream of the sheet 1 conveyed by the sheet feeding roller 2 in the conveying direction and elastically abuts on the outer peripheral surface of the sheet feeding roller 2. The ones are common. Then, the friction separating / feeding device using the friction separating pad 3 detects the friction force between the paper 1 and the paper feeding roller 2, between the paper 1 and the paper 1, and between the paper 1 and the friction separating pad 3. By utilizing the difference, the sheets 1 are separated and fed one by one.

[0004]

However, the above-mentioned frictional force and the friction coefficient of the paper 1, the paper feed roller 2, and the friction separation pad 3 are generated from the paper 1 due to changes in environmental conditions such as temperature and humidity. It fluctuates due to the attachment of paper powder or dust, deterioration of the paper feed roller 2 and the friction separation pad 3 over time, and the like.

Therefore, there is a case in which double feeding or non-feeding of the sheet 1 occurs even though the margin is set to some extent in the initial setting.

[0006]

The invention according to claim 1 is
A sheet feeding roller that sequentially conveys a plurality of stacked sheets from the side in contact with these sheets, and a sheet that is located on the downstream side in the sheet conveying direction and elastically contacts the outer peripheral surface of the sheet feeding roller. In a friction separation sheet feeding device having a friction separation pad in contact with the friction separation pad, inclination angle changing means for moving the friction separation pad in a direction for changing the inclination angle of the friction separation pad with respect to the sheet conveying direction is provided.

According to a second aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets of paper from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side in the conveying direction of the sheet of paper In a friction separating / feeding device having a friction separating pad elastically abutted on the outer peripheral surface of a paper roller, is the paper entering the paper separating unit where the paper feeding roller and the friction separating pad abut? A sensor that detects whether or not the friction separation pad is automatically moved so that the inclination angle of the friction separation pad with respect to the sheet conveyance direction is changed based on the detection result from the sensor. And.

According to a third aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets of paper from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side in the sheet conveying direction and has the sheet feeding roller. A friction separation pad elastically abutted on the outer peripheral surface of the paper roller, and a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad abut. And an automatic inclination angle changing means for automatically moving the friction separating pad so as to change the inclination angle of the friction separating pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. Is initially set to a large angle, and the inclination angle of the friction separation pad is set to be small from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Moving the friction separation pad toward, after the sensor detects the paper was to stop the movement of the friction separation pad.

According to a fourth aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets of paper from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side of the sheet in the conveying direction, A friction separation pad elastically abutted on the outer peripheral surface of the paper roller, and a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad abut. And an automatic inclination angle changing means for automatically moving the friction separating pad so as to change the inclination angle of the friction separating pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. Is initially set to a large angle, and the inclination angle of the friction separation pad is set to be small from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Moving the friction separation pad toward, after the sensor detects the sheet was made to move the friction separation pad to tilt angle increases direction of the frictional separation pad.

[0010]

According to the first aspect of the present invention, the inclination angle changing means moves the friction separation pad to change the inclination angle of the friction separation pad with respect to the sheet conveying direction. When this inclination angle is set to a large angle, it is difficult for the second and subsequent sheets of the paper conveyed by the paper feed roller to enter the paper separation section where the paper supply roller and the friction separation pad are in contact with each other. Double feed is prevented. on the other hand,
When this inclination angle is set to a small angle, the sheet conveyed by the sheet feed roller easily enters the sheet separating section, and the sheet is prevented from being unfed. Then, by properly adjusting the inclination angle in accordance with the type of paper, the variation in frictional force, and the like, double feeding and non-feeding of paper can be prevented.

According to the second aspect of the present invention, the sensor detects whether or not the sheet has entered the sheet separating section. Based on the detection result from the sensor, the friction separating pad is automatically changed by the automatic inclination angle changing means. And the inclination angle of the friction separating pad with respect to the sheet conveying direction is automatically changed. Therefore, if the friction separation pad is moved in the direction in which the inclination angle of the friction separation pad decreases from the start of sheet conveyance until the sensor detects the sheet, the inclination angle of the friction separation pad gradually increases. While the paper is getting smaller, only the paper that is in contact with the paper feed roller at the stage where the inclination angle is large enters the paper separating section, so that double feeding of the paper is prevented and the paper separating The sheet that does not easily enter the sheet section enters the sheet separating section when the inclination angle becomes small, so that the sheet is prevented from being unfed.

According to the third aspect of the present invention, the sensor detects whether or not the sheet has entered the sheet separating section. Based on the detection result from the sensor, the friction separating pad is automatically detected by the automatic inclination angle changing means. And the inclination angle of the friction separating pad with respect to the sheet conveying direction is automatically changed. The friction separation pad, which is initially set to a large inclination angle, is automatically moved in the direction in which the inclination angle decreases from the start of paper conveyance until the sensor detects the paper. The movement of the friction separation pad is stopped when the sensor detects that the removed paper has entered the paper separation unit. Therefore, when the inclination angle of the friction separation pad is gradually decreasing, only the paper that is in contact with the paper feed roller enters the paper separation portion when the inclination angle is large when the inclination separation angle is large. Double feeding of sheets is prevented, and sheets that are difficult to enter the sheet separating section are inserted into the sheet separating section when the inclination angle becomes small, so that the sheet is not fed.

According to the fourth aspect of the present invention, the sensor detects whether or not the sheet has entered the sheet separating section. Based on the detection result from this sensor, the friction separating pad is moved by the automatic inclination angle changing means. , The inclination angle of the friction separating pad with respect to the sheet conveying direction is changed.
Then, the friction separation pad initially set to a large inclination angle is moved by the automatic inclination angle changing means in a direction in which the inclination angle decreases from the start of the conveyance of the sheet until the sensor detects the sheet. Therefore, when the inclination angle of the friction separation pad is gradually reduced, only the paper that is in contact with the paper feed roller enters the paper separation portion when the inclination angle is large when the paper easily enters the paper separation portion. Double feeding of sheets is prevented, and sheets that are difficult to enter the sheet separating section are inserted into the sheet separating section when the inclination angle becomes small, so that no sheet feeding is prevented. Furthermore, after the sensor detects the paper, the friction separation pad is automatically moved in the direction that the inclination angle increases, so if a double-fed paper enters the paper separation section, those papers will be fed. The sheets are conveyed while being wound around the rollers, and a deviation occurs due to the difference in the radius of curvature between the sheets, and slippage easily occurs between one sheet in contact with the sheet feed roller and another sheet. As a result, only the sheet that is in contact with the sheet feed roller is continuously conveyed, and the conveyance of other sheets is stopped, so that the double feeding of the sheets can be prevented more reliably.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. The present embodiment corresponds to the invention described in claim 1. A paper feed roller shaft 4 is disposed above a paper feed cassette (not shown) set with the paper 1 stacked therein, and the paper feed roller shaft 4 is provided with the paper 1 as the uppermost paper. The paper feed roller 5 that sequentially conveys from 1 is fixed. A gear 6 is fixed to one end of the paper feed roller shaft 4, and the gear 6 meshes with a gear 9 fixed to a motor shaft 8 of a motor 7 for rotating the paper feed roller 5. Further, the paper feed roller shaft 4
Rotating arms 10 are rotatably attached to both ends of the rotating arm 10. At least one of the rotating arms 10 is formed in a substantially fan shape, and a gear 11 is formed in an arc-shaped peripheral portion. The paper feed roller shaft 4 is held by side plates (not shown) on both ends thereof.

A support rod 12 having an axis parallel to the paper feed roller shaft 4 is mounted between the pair of rotating arms 10. A mounting hole 13 is formed in the support rod 12 at a position facing the sheet feeding roller 5, and the mounting hole 13 is frictionally separated so as to elastically contact the outer peripheral surface of the sheet feeding roller 5. The legs 15 of the pad 14 are slidably inserted. The friction separating pad 14 is brought into contact with the outer peripheral surface of the paper feed roller 5 on the downstream side in the conveying direction of the sheet 1, and the outer peripheral surface of the paper feeding roller 5 of the friction separating pad 14 is contacted. The elastic contact with the friction spring is performed by the pressing force of the compression spring 16 mounted between the friction separating pad 14 and the support rod 12. Also,
A guide plate 18 for guiding the sheet 1 conveyed by the sheet feeding roller 5 toward the sheet separating portion 17 where the sheet feeding roller 5 and the friction separation pad 14 are in contact with each other is provided in the sheet feeding roller 5. It is arranged so as to face the outer peripheral portion.

Next, the gear 1 of the rotating arm 10
A gear 19 that meshes with the gear 1 is provided.
Is fixed to the motor shaft 21 of the motor 20. Then, the motor 20, the rotating arm 10, and the gear 1
9 and 11, the paper 1 by the paper feed roller 5
Inclination angle changing means 22 for rotating the friction separation pad 14 in a direction for changing the inclination angle of the friction separation pad 14 with respect to the conveyance direction of is formed.

In such a structure, when the paper feed roller 5 is rotationally driven in the direction of arrow a by driving the motor 7,
A feeding force is applied to the sheet 1 from the sheet feeding roller 5, and the uppermost sheet 1 and some sheets 1 positioned below the uppermost sheet 1 are conveyed. Then, when the leading ends of the sheets 1 come into contact with the guide plate 18, the second and subsequent sheets 1 are stopped from being conveyed at that position, and the sheet feeding roller 5 directly applies the conveying force to the uppermost sheet. Only the sheet 1 of No. 1 is continuously conveyed and enters the sheet separating unit 17, and the double feeding of the sheet 1 is prevented.

However, the paper feed roller 5 and the friction separation pad 1 are changed depending on the type of the paper 1, changes in environmental conditions such as temperature and humidity.
4 and two or more sheets 1 may enter the sheet separating section 17 and cause double feeding, or the sheet 1 may not enter the sheet separating section 17 and may not be fed depending on the change in the friction coefficient of the sheet 1 or the like. There is a case.

Therefore, in such a case, the motor 20
The rotation arm 10 is rotated around the paper feed roller shaft 4 by driving the. Then, the friction separation pad 14 also integrally rotates with the rotation of the rotation arm 10, and the inclination angle “θ” of the friction separation pad 14 with respect to the transport direction of the sheet 1 is changed. Here, if the inclination angle “θ” of the friction separating pad 14 is increased by rotating the rotating arm 10 in the counterclockwise direction (the direction of arrow b), the second and subsequent sheets 1 of the sheet 1 are separated. It becomes more difficult to enter the sheet 1, and the double feeding of the sheets 1 can be prevented more reliably. On the other hand, by rotating the rotating arm 10 in the clockwise direction (the direction of arrow c), the inclination angle “θ” of the friction separation pad 14 becomes small, and the conveyed sheet 1 easily enters the sheet separating portion 17. Moreover, the non-feeding of the sheet 1 is prevented.

Although the friction separating pad 14 is rotated by the motor 20 in this embodiment, the friction separating pad 14 is manually rotated. Good.

Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those described in FIGS. 1 and 2 are designated by the same reference numerals, and the description thereof will be omitted. In addition, this embodiment corresponds to the invention described in claim 2, 3 or 4. A sensor 23 that detects whether or not the conveyed sheet 1 has entered the sheet separating unit 17 is attached to the rotating arm 10. And this sensor 23
Is connected to a control unit (not shown) that controls the drive of the motor 20, and the motor 20 is controlled based on the detection result from the sensor 23. The sensor 23, the control unit, the motor 20, the gears 19 and 11, and the rotating arm 10 change the inclination angle of the friction separating pad 14 with respect to the conveying direction of the sheet 1 by the sheet feeding roller 5. An automatic inclination angle changing means 24 for automatically rotating the friction separating pad 14 is formed.

In such a structure, the friction separating pad 14 is rotated by rotating the rotating arm 10 in the counterclockwise direction (the direction of arrow b) before the conveyance of the sheet 1 is started.
The inclination angle “θ” of is set to a large angle in advance. From this state, when the paper feed roller 5 is rotationally driven based on the paper feed signal and the conveyance of the paper 1 is started, at the same time, a detection signal indicating that the paper 1 is not detected is input from the sensor 23 to the control unit. It Then, the motor 20 is driven based on this detection signal from the sensor 23, and the rotating arm 1
0 rotates in the clockwise direction (direction of arrow c), and the inclination angle “θ” of the friction separation pad 14 gradually decreases.

Then, when the inclination angle "θ" of the friction separating pad 14 reaches a certain angle, the conveyed sheet 1 is conveyed.
Enters the sheet separating section 17, and when the sheet 1 entering the sheet separating section 17 is detected by the sensor 23, the driving of the motor 20 is stopped based on the detection result, and the rotation operation of the friction separating pad 14 is also stopped. To be done. Therefore, in the case of the type of sheet 1 that easily enters the sheet separating unit 17 and easily causes double feeding, the inclination angle “θ” of the friction separating pad 14 is large.
Is large and it is difficult for the second and subsequent sheets 1 to enter the sheet separating section 17, only the uppermost sheet 1 is separated into the sheet separating section 17
The double feed is prevented. On the other hand, in the case of the paper 1 of the type that is difficult to enter the paper separating unit 17 and is easily fed, only the uppermost paper 1 is formed when the inclination angle “θ” of the friction separating pad 14 becomes sufficiently small. As it comes into the separating portion 17, non-feeding is prevented.

It should be noted that the conveyed sheet 1 has a sheet separating section 17
When the sensor 23 no longer detects the sheet 1 after passing through, the motor 20 is driven in the direction to rotate the rotating arm 10 in the direction of arrow b, and the friction separating pad 14 has the largest inclination angle "θ". Return to the initial state.

After the sensor 23 detects the sheet 1 that has entered the sheet separating portion 17, the motor 23 is driven in a direction to rotate the rotating arm 10 in the direction of arrow b, so that the sheet 1
Even when the sheet has entered the sheet separating section 17 in the double-feed state, the sheet 1 that has been double-fed as the friction separation pad 14 rotates in the direction to increase the inclination angle “θ”
Since the sheet 1 is conveyed in a state of being wound around the sheet 1, a deviation occurs due to the difference in the radius of curvature between the sheets 1 that have been double-fed, and between the sheet 1 that is in contact with the sheet feed roller 5 and another sheet 1. Slipping easily occurs, and only the uppermost sheet 1 in contact with the sheet feeding roller 5 is continuously conveyed and the conveyance of the other sheets 1 is stopped, so that the double feeding of the sheets 1 can be prevented more reliably. It

In this case, when the sheet 1 passes through the sheet separating portion 17 and the sensor 23 stops detecting the sheet 1, the rotating arm 10 continues to rotate in the direction of arrow b and the friction separating pad 14 is moved. Returns to the initial state in which the tilt angle “θ” becomes maximum.

[0027]

According to the first aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side in the sheet conveying direction. In a friction separating paper feeding device having a friction separating pad elastically abutted on the outer peripheral surface of the paper feeding roller,
Since the inclination angle changing means for moving the friction separating pad in the direction for changing the inclination angle of the friction separating pad with respect to the sheet conveying direction is provided, the inclination angle changing means increases the inclination angle of the friction separating pad. In this case, it is possible to prevent the second and subsequent sheets of the sheets conveyed by the sheet feeding roller from easily entering the sheet separating portion where the sheet feeding roller and the friction separating pad are in contact with each other, thereby preventing double feeding. On the other hand, when the inclination angle of the friction separation pad is set to a small angle, it is possible to prevent the sheet conveyed by the sheet feed roller from easily entering the sheet separation section and prevent non-feeding.

According to a second aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets of paper from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side in the sheet conveying direction and has the sheet feeding roller. In a friction separating / feeding device having a friction separating pad elastically abutted on the outer peripheral surface of a paper roller, is the paper entering the paper separating unit where the paper feeding roller and the friction separating pad abut? A sensor that detects whether or not the friction separation pad is automatically moved so that the inclination angle of the friction separation pad with respect to the sheet conveyance direction is changed based on the detection result from the sensor. Since the and are provided, it is possible to automatically move the friction separation pad in the direction in which the inclination angle of the friction separation pad decreases from the start of sheet conveyance until the sensor detects the sheet. As the inclination angle of the friction separation pad gradually decreases, only the paper that is in contact with the paper feed roller enters the paper separation section when the inclination angle is large when the paper easily enters the paper separation section. It is possible to prevent double feeding and to prevent non-feeding because a sheet that is difficult to enter the sheet separating section enters the sheet separating section when the inclination angle becomes small. ..

According to a third aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets from the side in contact with these sheets, and the sheet feeding roller that is located on the downstream side in the sheet conveying direction. A friction separation pad elastically abutted on the outer peripheral surface of the roller; a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad abut; An automatic inclination angle changing means for automatically moving the friction separation pad so as to change the inclination angle of the friction separation pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. The inclination angle is initially set to a large angle, and the inclination angle of the friction separation pad becomes small from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Since the friction separation pad is moved in the same direction and the movement of the friction separation pad is stopped after the sensor detects the sheet, the movement of the sheet is started until the sensor detects the sheet. During this period, the friction separation pad is automatically moved in the direction in which the inclination angle decreases. Therefore, when the inclination angle of the friction separation pad gradually decreases, the paper that easily enters the paper separation section has a large inclination angle. Since only the paper that is in contact with the paper feed roller will enter the paper separating section, it is possible to prevent double feeding, and for paper that is difficult to enter the paper separating section, separate the paper at the stage when this inclination angle becomes small. Since it comes into the part, there is an effect such that non-feeding can be prevented.

According to a fourth aspect of the present invention, a sheet feeding roller that sequentially conveys a plurality of stacked sheets from the side in contact with these sheets, and a sheet feeding roller that is located on the downstream side in the sheet conveying direction and has the sheet feeding roller. A friction separation pad elastically abutted on the outer peripheral surface of the paper roller, and a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad abut. And an automatic inclination angle changing means for automatically moving the friction separating pad so as to change the inclination angle of the friction separating pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. Is initially set to a large angle, and the inclination angle of the friction separation pad is set to be small from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Since the friction separating pad is moved in the direction, since the friction separating pad is automatically moved in the direction in which the inclination angle decreases from the start of the sheet conveyance to the detection of the sheet by the sensor, As the inclination angle of the separation pad gradually decreases, for paper that easily enters the paper separation section, only the paper that is in contact with the paper feed roller enters the paper separation section when the inclination angle is large. Double feed can be prevented, and paper that does not easily enter the paper separating section will enter the paper separating section when the angle of inclination becomes small, so non-feeding can be prevented. After detecting the paper, the friction separation pad was automatically moved in the direction of increasing the inclination angle, so if a double-fed paper enters the paper separation section, Since the paper is conveyed while being wound around the paper feed roller, there is a gap between the papers due to the difference in the radius of curvature, and there is a gap between one paper that is in contact with the paper feed roller and another paper. Makes it easier to slip, and only one sheet of paper that is in contact with the paper feed roller is continuously conveyed and the conveyance of other sheets is stopped, so that double feeding of sheets can be prevented more reliably. Have the effect of.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of the present invention,
(A) shows the mounting state of the friction separation pad, (b) shows the mounting state of the rotating arm, and (c) shows the combined state.

FIG. 2 is a front view.

FIG. 3 is a side view showing a second embodiment of the present invention,
(A) shows the attachment state of the friction separation pad, (b) shows the attachment state of the rotating arm, and (c) shows the state in which they are combined.

FIG. 4 is a side view showing a conventional example.

[Explanation of symbols]

 1 Paper 5 Paper Feed Roller 14 Friction Separation Pad 17 Paper Separation Part 22 Inclination Angle Change Means 23 Sensor 24 Automatic Inclination Angle Change Means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoki Kato 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd. (72) Yasuyuki Okada 1-3-3 Nakamagome, Ota-ku, Tokyo Shares Within Ricoh Company (72) Inventor Motomi Ozaki 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Company, Ltd.

Claims (4)

[Claims] 1. A paper feed roller that conveys a plurality of stacked sheets in order from the side in contact with these sheets, and a downstream side of the sheet in the conveyance direction and an outer peripheral surface of the paper feed roller. In a friction separation sheet feeding device having a friction separation pad elastically abutted, an inclination angle changing means for moving the friction separation pad in a direction for changing an inclination angle of the friction separation pad with respect to a conveyance direction of the sheet. A friction separation sheet feeding device characterized by being provided with. 2. A paper feed roller which conveys a plurality of stacked paper sheets in order from the side in contact with these paper sheets, and a downstream side of the paper sheet in the conveyance direction and an outer peripheral surface of the paper feed roller. In a friction separation sheet feeder having a friction separation pad elastically abutted, a sensor for detecting whether or not the sheet has entered a sheet separation section where the sheet supply roller and the friction separation pad are in contact with each other. And an automatic inclination angle changing means for automatically moving the friction separation pad so as to change the inclination angle of the friction separation pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. Characteristic friction separation paper feeder. 3. A paper feed roller that conveys a plurality of stacked sheets in order from the side in contact with these sheets, and a downstream side of the sheet in the conveyance direction and an outer peripheral surface of the sheet feed roller. A friction separation pad elastically contacted, and a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad are in contact with each other,
And an automatic inclination angle changing means for automatically moving the friction separating pad so as to change the inclination angle of the friction separating pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. The inclination angle of the friction separation pad is initially set to a large angle, and the inclination angle of the friction separation pad decreases in the direction from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Is moved so that the movement of the friction separating pad is stopped after the sensor detects the sheet, and the friction separating sheet feeding method. 4. A paper feed roller that conveys a plurality of stacked sheets in order from the side in contact with these sheets, and a paper feed roller that is located on the downstream side in the sheet conveyance direction and on the outer peripheral surface of the paper feed roller. A friction separation pad elastically contacted, and a sensor for detecting whether or not the paper has entered the paper separation unit where the paper feed roller and the friction separation pad are in contact with each other,
And an automatic inclination angle changing means for automatically moving the friction separating pad so as to change the inclination angle of the friction separating pad with respect to the conveyance direction of the sheet based on the detection result from the sensor. The inclination angle of the friction separation pad is initially set to a large angle, and the inclination angle of the friction separation pad decreases in the direction from the start of the conveyance of the sheet to the detection of the sheet by the sensor. Is moved so that after the sensor detects the sheet, the friction separation pad is moved in a direction in which the inclination angle of the friction separation pad increases.