JPH09194065A - Sheet feeder and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent defective feeding such as double-feed of a sheet so as to handle varied kinds of sheets by changing an oscillational slanting face, which is used for separating a fed sheet previously, interlockingly with the oscillation of a pressing means. SOLUTION: A pressing plate 2 serving as a pressing means is joumalled to a main body frame 1 oscillationally around a shaft 2a. When a line feed roller 5 is rotated in the feeding direction, the pressing plate 2 presses a sheet member S on the pressing plate 2 onto the roller 5 by means of a spring 3, and the sheet member S is picked up so as to be fed. A slanting face 7 is oscillated interlockingly when an oscillation of the pressing plate 2 is transmitted by means of a gear train 16-18, and the slanting face is inclined at a proper angle according to the number of placed sheet members S. Therefore, the sheet member in the upper position is conveyed by means of the roller 5, while the sheet member in the lower position is stopped by means of resistance of the slanting face 7, so that defective feeding such as double-feed is not generated even if a plurality of sheets are picked up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material feeding device used in an image forming apparatus such as a copying machine, a printer, a facsimile, etc., and more particularly to a sheet material for sequentially separating and feeding sheet materials one by one from a sheet bundle. The present invention relates to a material feeding device.

[0002]

2. Description of the Related Art Conventionally, as a sheet material feeding device used in an image forming apparatus such as a copying machine, as shown in FIG. 6, for example, a feeding device using a torque limiter type separating roller is generally known. ing. As shown in FIG. 6, this feeding device has a rubber layer on the outer peripheral surface thereof, and a line feed roller 10 which is rotated by a driving force transmitted from a motor through a gear.
1, a swing-type pressure plate 104 that is swingably supported by the frame 102 and is urged in the direction of the roller 101 by a spring 103, and a regulating member (not shown) that regulates the swing of the pressure plate 104. ) And a torque limiter type separation roller 105 that has a rubber layer on the outer peripheral surface and swings in conjunction with the movement of the pressure plate 104, and an inclined surface that is fixed to the frame 102 and that assists the separation of the sheet material. It is composed of an inclined surface 106 and the like. Sheet material S separated and fed by this feeding device
A plurality of sheets are set on the stacker 107 of the apparatus.

When the above-mentioned conventional feeder is used for feeding, first the line feed roller 101 is rotated in the feeding direction (the direction of the arrow in the figure). Then, the restriction of the pressure plate 104 by the restriction member is released, and the pressure plate 104 swings in the direction of the roller 101 about the axis by the bias of the spring 103. At this time, the pressure plate
The separation roller 105 also moves in accordance with the movement of the roller 104.
Swing in the direction of. The sheet material S pressed against the line feed roller 101 by the pressure plate 104 urged by the spring 103.
The uppermost one sheet or a plurality of upper sheets are picked up from the stacker 107 by the frictional force with the line feed roller 101, and are conveyed in the rotation direction of the line feed roller 101.

Here, when a plurality of sheet materials are fed, they are separated by the separation roller 105 on the downstream side of the pressure plate 104 in the conveying direction. And the line feed roller 101
When the sheet material is rotated to some extent in order to convey the sheet material to the image forming portion, the regulation member regulates the swing of the pressure plate 104 again (lowers the pressure plate). Separation roller 10 linked to it
5 also swings and retracts from the line feed roller 101, and waits for the next feeding operation. Here, the sheet separation by the separation roller 105 will be described.

First, a case where only the uppermost one sheet material enters the nip portion between the separation roller 105 and the line feed roller 101 will be described with reference to FIG. The upper surface of the sheet material S1 contacts the line feed roller 101, and the lower surface of the sheet material S1 contacts the separation roller 105. The sheet material S1 receives a force in the conveying direction due to the frictional force between the line feed roller 101 and the upper surface of the sheet material S1. A frictional force is also generated between the lower surface of the sheet material S1 and the separating roller 105. However, since the separating roller 105 exceeds the torque limit, the separating roller 105 is driven by the sheet material S1 having a conveying force. Rotate. That is, if only the uppermost one sheet material enters the roller nip portion due to the conveying force of the line feed roller 101> the braking force of the torque limiter of the separation roller 105, the uppermost one sheet material Only can be transported.

Next, a case where two sheet materials enter the roller holding portion will be described with reference to FIG.
The upper sheet material S1 has a line feed roller 10 on the upper surface.
1, and the lower surface is in contact with the upper surface of the lower sheet material S2.
The lower surface of the lower sheet material S2 is in contact with the separation roller 105. Here, since the relationship of the forces acting on the upper sheet material S1 is: upper surface> lower surface, the upper sheet material S1 is conveyed in the conveying direction, but the relationship of the forces acting on the lower sheet material S2 is the upper surface < Since it is on the lower surface, the separation roller 105 does not rotate, and the lower sheet material S2 stops on the separation roller 105. That is, when two sheets of material enter the roller holding section, the lower sheet material S2 stops on the separation roller 105, and only the upper sheet material S1 is conveyed, and the sheet material S1 and the sheet material S2 are conveyed. Since it is separated from, only the uppermost sheet material can be conveyed.

Next, a case where three or more sheet materials enter the roller holding portion will be described with reference to FIG. Similar to the above, since the relationship of the forces acting on the upper sheet material S1 is the upper surface> the lower surface, the upper sheet material S1 is conveyed and the relationship of the forces acting on the lower sheet material S2 is the upper surface <lower surface. Therefore, the lower sheet material S2 is the separation roller 10
5 Stop on top. However, since each surface of the middle sheet material S3 is in contact with the upper sheet material S1 and the lower sheet material S2, the relationship of the force (friction force) acting on the middle sheet material S3 is the upper surface ≈ Since it is on the lower surface and the difference in frictional force between both surfaces is small, it is not possible to reliably stop the middle sheet material S3 only by the separating roller 105. That is, when three or more sheet materials enter the roller holding portion, the sheet materials may be double-fed.

As described above, due to the structure of the separating roller 105 alone, when one or two sheets of material enter the roller holding portion, the separation of the sheet material is surely performed, and the uppermost sheet is separated. However, if three or more sheet materials enter the roller nip portion, it is not possible to reliably separate the sheet materials, and there is a possibility that double feeding may occur. is there.

Therefore, the inclined surface of the inclined surface 106 provided in the vicinity of the separation roller 105 assists the separation of the sheet by the separation roller 105. That is, the inclined surface of the inclined surface 106 is provided for the purpose of preventing a plurality of sheets (especially three or more sheets) from entering the nipping portion between the line feed roller 101 and the separation roller 105.

The function of the inclined surface 106 will be described with reference to FIG. The inclined surface 106 is provided in the vicinity of the separation roller 105 and is formed of an inclined surface having an appropriate angle. Therefore,
The sheet material S1 that has been picked up hits the slope of the slope 106 before entering the roller nip. At this time, the conveying force from the line feed roller 101 and the drag force of the inclined surface of the inclined surface 106 act on the sheet material S1. The relationship between the conveying force acting on the sheet material S1 and the drag force on the slope is that if the conveying force is smaller than the drag force on the slope, the picked-up sheet material stops at the slope of the slope 106 and is not conveyed to the downstream side. , Conveyance force> Slope resistance must be met.

Further, when a plurality of sheet materials are picked up, the lower sheet material S2 (or S3) is conveyed by friction with the upper sheet material S1 (or S2) and the drag force of the inclined surface 106. Works. If the relationship between the conveying force acting on the sheet material S2 (or S3) and the drag force on the slope is such that the conveying force> the drag force on the slope surface, the lower sheet material S2 (or S3) resists the drag force on the slope surface and the separating roller. Since it enters 105, it is necessary that the conveying force is less than the slope drag.

Therefore, the proper value of the slope of the slope 106 is the conveying force (friction force) from the line feed roller 101.
> Drag force of inclined surface 106> An angle within a range that satisfies the conveying force (friction force) between sheet materials, and is fixed within this range.

[0013]

However, in the above-mentioned conventional example, since the inclined surface 106 for assisting the separation of the sheet material is a fixed type, there are the following problems.

In recent years, a variety of sheet materials such as recording papers used in image forming apparatuses have become available and the properties of each sheet material have become large.
The angle of inclination of was limited to a very narrow range. For example, for sheet materials with a low coefficient of friction, line feed rollers
The frictional force with 101 decreases, and the frictional force between sheet materials increases in the case of a sheet material having a high friction coefficient. Therefore, the above condition (conveyance force from line feed roller 101> drag force of inclined surface 106> slope between sheet materials> The angle range (appropriate value) of the slope satisfying the carrying force) was very narrow.

Thus, the angle of the slope of the slope 106 is
With the diversification of sheet materials, the proper value is limited to a very narrow range, and if the proper value is deviated, it causes a feeding failure such as double feeding.

Further, the drag force of the inclined surface of the inclined surface 106 against the sheet material changes depending on the number of stacked sheet materials on the stacker 107, and thus may deviate from an appropriate value within a narrow range. That is, when the number of stacked sheet materials is large, the amount of swing of the pressure plate 104 is small, so that the inclined surface with respect to the sheet material is
The slope angle of 106 becomes higher than the set value, and the drag force of the slope becomes large. On the contrary, when the number of stacked sheet materials is small, the amount of rocking of the pressure plate 104 is large, so that the angle of the slope of the inclined surface 106 with respect to the sheet material becomes more slanted than the set value, and the drag force of the slope becomes small. In this way, even if the number of sheet materials stacked on the stacker 107 is increased, the inclined surface 10
There is a possibility that it will deviate from the proper value of the angle of 6 slope,
This was a cause of defective feeding such as double feeding.

The present invention has been made in view of the above problems, and an object of the present invention is to prevent feeding defects such as double feeding of sheet materials and to cope with various diversified sheet materials. It is to provide a material feeding device.

[0018]

A typical structure of the present invention for achieving the above object is to provide a feeding means for picking up and feeding a sheet material, and a swingingly provided sheet material. A pressing means for pressing the feeding means, a separating means for separating the sheet materials fed by the feeding means one by one, and arranged on the upstream side of the sheet material conveying direction of the separating means, A sloping inclined surface for separating in advance by abutting the sheet material sent out by the feeding means, and an interlocking means for changing the inclination angle of the inclined surface in association with the oscillating movement of the pressing means, It is characterized by having.

According to the above construction, since the inclined surface is oscillated in association with the pressing means which is oscillated according to the number of stacked sheet materials, the inclined surface with respect to the sheet material to be picked up and fed. The angle of the slope is corrected according to the number of stacked sheet materials, and thus feeding failure such as double feeding of sheet materials can be prevented.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a sheet material feeding device according to the present invention will be described. The sheet material feeding device according to the present invention is used as a feeding device of an image forming apparatus such as a copying machine, a printer, and a facsimile, and is used as a sheet material such as paper as an image forming object or as an image reading object. The sheet material such as the original document is fed toward the image forming unit or the image reading unit. In the following description, a sheet material feeding device that feeds a sheet material such as paper as an image forming target to the image forming unit will be described as an example.

[First Embodiment] A sheet material feeding device according to a first embodiment will be described with reference to Figs.
FIG. 1 is an overall perspective view showing a schematic configuration of a sheet material feeding device according to the present embodiment, FIG. 2 is a sectional view of an essential part of the sheet material feeding device, and FIG. 3 is a schematic diagram showing a relationship between a pressure plate and an inclined surface. FIG.

1 to 3, reference numeral 1 denotes a main body frame, to which various members to be described later are attached. Reference numeral 2 denotes a pressure plate as a pressing means, which has a shaft 2a on the upstream side in the conveying direction, is axially supported by the main body frame 1 by the shaft 2a, and can swing about the shaft 2a. The pressure plate 2 is biased in the direction of the line feed roller 5 by a spring 3 arranged on the lower surface side, and supplies the sheet material S on the stacker 6 capable of stacking and accommodating a plurality of sheet materials S. It has a function of pressing the line feed roller 5 at the time of feeding. That is, normally (at the time of non-feeding), it is restricted to the solid line position in FIG. 2 by the restriction member 4 shown by the broken line in FIG. Then, at the time of feeding, the regulation by the regulation member 4 is released and the sheet material S is swung to a position where it is pressed against the line feed roller 5 (position indicated by a chain double-dashed line in FIG. 2). A gear 16 for transmitting a driving force to an inclined surface 7 described later is attached to the shaft 2a of the pressure plate 2.

Line feed roller 5 as a feeding means
Is a roller for picking up the sheet material S pressed by the pressure plate 2 and carrying the sheet material S. The line feed roller 5 is rotatably supported by the main body frame 1 and has a rubber 10 on its surface.
Is provided. A gear 14 that engages with a gear 13 of a pulse motor 12 that is a drive source and receives a drive force is attached to one end (drive source side) of the line feed roller 5 in the longitudinal direction.

The separating roller 8 as a separating means is a roller for separating the sheet materials S picked up by the line feed roller 5 one by one. In this embodiment, a torque limiter type separating roller is used. There is.
That is, although not shown, the separation roller 8 has a one-way clutch arranged on a shaft serving as a center of rotation, and when the separation roller 8 receives a rotational force (conveyance force) exceeding the torque limit of the one-way clutch during separation and feeding, It is adapted to rotate in the transport direction. The separating roller 8 is axially supported by a swingable holder 9, and a rubber 11 is provided on the surface thereof.

The holder 9 has a shaft 9 on the downstream side in the carrying direction.
The shaft 9a is pivotally supported by the main body frame 1 by the shaft 9a and is biased by the spring 15 toward the line feed roller 5. A rib 9b is provided at the tip (free end) of the holder 9, and the swing of the holder 9 is regulated by the rib 9b being regulated by the normal pressure plate 2. Here, when the pressure plate 2 swings, the regulation of the rib 9b is released, so that the separation roller 8
The holder 9 which pivotally supports is also rocked. That is, when the pressure plate 2 is regulated by the regulation member 4 (solid line position in FIG. 2), the separation roller 8 is retracted together with the holder 9 to a position separated from the line feed roller 5. When the regulation by the regulation member 4 is released and the sheet material is pressed against the line feed roller 5 (the position of the chain double-dashed line in FIG. 2), the regulation of the holder 9 is also released,
The separation roller 8 contacts the line feed roller 5 by the urging force of the spring 15.

The inclined surface 7 is used for preliminarily separating the sheet material S sent out by the line feed roller 5 when the sheet material S abuts against it.
Is arranged on the upstream side in the transport direction. This inclined surface 7
Has a shaft 7a on the downstream side in the transport direction.
Is swingably supported by the body frame 1. Also, the pressure plate 2 is attached to the shaft 7a of the inclined surface 7 via a gear 18.
A gear 17 for receiving the drive of the gear 16 attached to the end of the is attached. Gear train 16 as this interlocking means
The transmission of the driving force 18 causes the inclined surface 7 to swing in conjunction with the swing of the pressure plate 2.

Next, the sheet material feeding process in the sheet material feeding apparatus having the above-mentioned configuration will be described in detail. In the feeding standby state, the pressure plate 2 is regulated by the regulation member 4 and stands by at the position (solid line position in FIG. 2) where the sheet material S is separated from the line feed roller 5 against the biasing force of the spring 3. There is. Further, the separation roller 8 is also retracted to a position separated from the line feed roller 5 because the rib 9b of the holder 9 that pivotally supports the separation roller 8 is restricted by the pressure plate 2.

When the pulse motor 12 is driven, the driving force is transmitted to the line feed roller 5 via the gears 13 and 14, and the line feed roller 5 rotates in the feeding direction (counterclockwise direction in the figure). To do. Then, the restriction of the pressure plate 2 by the restriction member 4 is released, the pressure plate 2 is swung in the direction of the line feed roller 5 by the urging force of the spring 3, and the sheet material S on the pressure plate 2 is pressed against the line feed roller 5. To do. Then, as for the sheet material S, a conveying force is applied to the line feed roller 5 rotating in the feeding direction, and the uppermost one sheet or a plurality of upper sheets are picked up from the stacker 6 and the line feed roller 5 moves. It is paid out in the direction of rotation.

At the same time, when the pressure plate 2 swings in the direction of the line feed roller 5 as described above, the regulation of the rib 9b of the holder 9 which pivotally supports the separation roller 8 is released, so that the holder 9 is moved. The urging force of the spring 15 causes the line feed roller 11 to swing about the shaft 9a, the separation roller 8 is pressed by the line feed roller 5, and the frictional force thereof causes the line feed roller 5 to rotate in the feeding direction.

Further, as the pressure plate 2 swings, the pressure plate 2
The gear 16 attached to the end of the pressure plate 2 is centered on the shaft 2a.
Rotate in the same direction (counterclockwise direction in the figure) by the amount of rocking. With the rotation of the gear 16, the gear 17 attached to the end of the inclined surface 7 via the intermediate gear 18 also rotates in the same direction (counterclockwise direction in the drawing). Accordingly, the swingable inclined surface 7 is rotated counterclockwise by the swing amount of the pressure plate 2 (see FIG. 2).
Rocking from the solid line position to the broken line position).

Here, the swing of the pressure plate 2 is caused by the stacker 6
It is performed until the sheet materials S stacked and accommodated on the sheet collide with the line feed roller 5. Therefore, the swing amount is small when the number of the sheet materials S stacked is large, and conversely when the number of the sheet materials S stacked is small. Will increase. The amount of swing of the inclined surface 7 that assists the separation of the separation roller 8 corresponds to the amount of swing of the pressure plate 2, so the sheet material S on the pressure plate 2 is formed.
The angle of the inclined surface of the inclined surface 7 is always an appropriate angle according to the number of stacked sheet materials S, that is, the swing amount of the pressure plate 2.

Therefore, the sheet material S picked up by the line feed roller 5 hits the slope of the inclined surface 7 before entering the nipping portion with the separation roller 8. At this time, the conveying force from the line feed roller 5 and the drag force of the inclined surface of the inclined surface 7 act on the sheet material S. Furthermore,
When a plurality of sheet materials are picked up, a frictional force with a lower sheet material also works. However, as described above, since the angle of the slope of the inclined surface 7 with respect to the sheet material S always takes an appropriate angle according to the number of stacked sheet materials S on the stacker 6, the slope of the sheet material S and the inclined surface 7 The relationship of the drag force is: conveyance force from line feed roller 5> slope 7
Slope resistance> The condition of the frictional force between the sheet materials S is always satisfied. That is, the upper sheet material is the line feed roller 5
And the lower sheet material is stopped at the slope of the slope 7. Therefore, it is possible to prevent a plurality of sheets (in particular, three sheets or more) of sheet materials from entering between the line feed roller 5 and the separation roller 8.

As described above, in this embodiment, even when a plurality of sheet materials S are picked up, the drag force of the inclined surface 7 does not affect the number of stacked sheet materials S on the stacker 6. Since the lower sheet material is stopped and the load on the separating roller 8 is reduced, it is possible to prevent three or more sheet materials from entering between the line feed roller 5 and the separating roller 8, and thus the sheet It is possible to prevent defective feeding such as double feeding of materials.

[Second Embodiment] Next, a sheet material feeding device according to a second embodiment will be described with reference to FIG.
FIG. 4 is a schematic cross-sectional view showing the relationship between the pressure plate and the inclined surface of the sheet material feeding device according to the present embodiment. Since the configuration of the entire apparatus is substantially the same as that of the above-described embodiment, detailed description will be omitted here. Further, members having the same functions as those of the above-described embodiment are denoted by the same reference numerals. Hereinafter, the characteristic portion of the sheet material feeding device according to the present embodiment will be described.

In this embodiment, as the interlocking means, there is provided a link mechanism in which the ends of the arms 19 and 20 rotatably attached to the inclined surface 7 and the pressure plate 2 are rotatably coupled. The link mechanism changes the tilt angle of the tilted surface 7 in association with the swing of the pressure plate 2.

In FIG. 4, the pressure plate 2 as a pressing means has a shaft 2a on the upstream side in the carrying direction, and the shaft 2a is pivotally supported by the main body frame 1 and can swing about the shaft 2a. , Are urged upward (in the direction of the line feed roller) by the spring 3. The pressure plate 2 has an arm mounting shaft 2b at the downstream end in the transport direction, and a rotatable arm 19 is mounted on the shaft 2b.

The inclined surface 7 has a shaft 7a on the downstream side in the conveying direction, and is pivotally supported by the main body frame 1 by the shaft 7a. Further, the inclined surface 7 has an arm mounting shaft 7b at the upstream end in the transport direction, and a rotatable arm 20 is mounted on the shaft 7b.

The arms 19 and 20 attached to the pressure plate 2 and the inclined surface 7 respectively include the arm attachment shafts 2b and
At the end opposite to 7b, each is rotatably connected by a shaft 21. This shaft 21 is the main frame 1
It is slidably attached to the crescent-shaped groove 1a provided in the.

An arm 19 rotatably attached to the shaft 2b of the pressure plate 2, an arm 20 rotatably attached to the shaft 7b of the inclined surface 7, and the arms 19 and 20 are each rotatable. The groove 1a of the main body frame 1 slidably supporting the shaft 21 thus connected constitutes a link mechanism as an interlocking means for rocking the inclined surface 7 according to the rocking of the pressure plate 2.

Next, the operation of the link mechanism will be described in detail. First, in the feeding standby state, the pressure plate 2 is regulated by the regulation member and stands by at a position (solid line position in FIG. 4) where the sheet material S is separated from the line feed roller against the biasing force of the spring 3. There is. At this time, the angle between the pressure plate 2 and the arm 19 is the largest in the movable range, and the connecting shaft 21 is also positioned substantially at the upper end of the crescent-shaped groove 1a of the main body frame 1. At this time, the inclined surface 7 is in the most lying state in the movable range (solid line position in FIG. 4), and the angle between the inclined surface 7 and the arm 20 is also the smallest in the movable range.

When the restriction by the restriction member is released, the pressure plate 2 swings in the direction of the line feed roller about the shaft 2a by the urging force of the spring 3. At this time, the pressure plate 2 swings until the sheet material S on the stacker 6 hits the line feed roller, as in the above-described embodiment. The arm 19 rotates in response to the swing of the pressure plate 2, and the shaft 21 slides along the crescent-shaped groove 1a of the main body frame 1 in the substantially lower end direction in response to the swing. The arm 20 rotates in response to the movement of the shaft 21, and the inclined surface 7 swings accordingly. That is, the link mechanism causes the inclined surface 7 to swing by an amount corresponding to the swing amount of the pressure plate 2.

Here, the swing amount of the pressure plate 2 is determined by the sheet material S.
When the number of stacked sheets is large, the number is small, and when the number of stacked sheets S is small, the number is large. As described above, since the swing amount of the inclined surface 7 corresponds to the swing amount of the pressure plate 2, the sheet material S
The angle of the inclined surface of the inclined surface 7 is always an appropriate angle according to the number of stacked sheet materials S.

As described above, in this embodiment, even when a plurality of sheet materials S are picked up, the drag force of the inclined surface of the inclined surface 7 does not affect the number of stacked sheet materials S on the stacker 6. Since the lower-order sheet material is stopped to reduce the load on the separation roller, it is possible to prevent three or more sheet materials from entering between the line feed roller and the separation roller. It is possible to prevent feeding defects such as feeding.

[Third Embodiment] Next, a sheet material feeding device according to a third embodiment will be described with reference to FIG.
FIG. 5 is a schematic cross-sectional view showing the relationship between the pressure plate and the inclined surface of the sheet material feeding device according to the present embodiment. Since the configuration of the entire apparatus is substantially the same as that of the above-described embodiment, detailed description will be omitted here. Further, members having the same functions as those of the above-described embodiment are denoted by the same reference numerals. Hereinafter, the characteristic portion of the sheet material feeding device according to the present embodiment will be described.

In this embodiment, as the interlocking means, the spring 23 as the urging means urges the line feed roller in the direction of the line feed roller, and the stopper 1b restricts the swinging, and is formed in front of the end of the pressure plate 2. Tapered portion 22a of rib 22
Has a mechanism in which a part of it is in contact, and is configured to change the inclination angle of the inclined surface 7 in conjunction with the swing of the pressure plate 2.

In FIG. 5, the pressure plate 2 as a pressing means has a shaft 2a on the upstream side in the carrying direction, and the shaft 2a is pivotally supported by the main body frame 1 and can swing about the shaft 2a. , Are urged upward (in the direction of the line feed roller) by the spring 3. A rib 22 having a cam tip is attached to the downstream end of the pressure plate 2 in the transport direction, and the tapered portion 22a of the rib 22 is in contact with a part of the inclined surface 7.

The inclined surface 7 has a shaft 7a on the downstream side in the conveying direction, and the shaft 7a is swingably supported by the main body frame 1. The inclined surface 7 is biased in the direction of the line feed roller by a spring 23 as a biasing means, and its swinging is restricted by a stopper 1b provided on the main body frame 1.

Next, the operation of the above mechanism will be described in detail. First, in the feeding standby state, the pressure plate 2 is regulated by the regulation member, and stands by at the position (solid line position in FIG. 5) where the sheet material S is separated from the line feed roller against the bias of the spring 3. There is. At this time, the ribs 22 attached to the pressure plate 2
The taper portion 22a of the above is in contact with a part of the inclined surface 7. On the other hand, the inclined surface 7 is biased in the direction of the line feed roller by the biasing force of the spring 23, and the stopper 1b of the body frame 1 is pushed.
It is in a state of hitting.

When the regulation by the regulation member is released, the pressure plate 2 swings in the direction of the line feed roller about the shaft 2a by the urging force of the spring 3. At this time, the pressure plate 2 swings until the sheet material S on the stacker 6 hits the line feed roller, as in the above-described embodiment. At this time, the taper portion 22a of the rib 22 attached to the pressure plate 2 is
The inclined surface 7 is pushed counterclockwise in the figure against the biasing force of the spring 23. That is, by the mechanism described above, the inclined surface 7 swings by an amount corresponding to the swing amount of the pressure plate 2.

Here, the swing amount of the pressure plate 2 is determined by the sheet material S.
When the number of stacked sheets is large, the number is small, and when the number of stacked sheets S is small, the number is large. As described above, since the swing amount of the inclined surface 7 corresponds to the swing amount of the pressure plate 2, the sheet material S
The angle of the inclined surface of the inclined surface 7 is always an appropriate angle according to the number of stacked sheet materials S.

As described above, in the present embodiment, even when a plurality of sheet materials S are picked up, the drag force of the inclined surface of the inclined surface 7 does not affect the number of stacked sheet materials S on the stacker 6. Since the lower-order sheet material is stopped to reduce the load on the separation roller, it is possible to prevent three or more sheet materials from entering between the line feed roller and the separation roller. It is possible to prevent feeding defects such as feeding. Further, the number of parts is smaller than that of the above-described embodiment, and the configuration can be simplified, which is advantageous in terms of cost.

[Other Embodiments] In the above-described embodiment,
Although the sheet material feeding device for feeding the sheet material such as paper as the image forming object to the image forming unit has been described as an example, the present invention is not limited to this. For example, even when the present invention is applied to a sheet material feeding device that feeds a sheet material such as a document as an image reading target to the image reading unit, the same effects as the above-described effects can be obtained. The sheet material feeding device is used as a feeding device for feeding the sheet material to the image forming unit or the image reading unit of the image forming apparatus. The image forming apparatus includes a copying machine and a printer. , A facsimile, a scanner, etc., and by applying the present invention, the same effects as the above-described effects can be obtained.

[0053]

As described above, according to the present invention,
It is possible to cope with various diversified sheet materials and prevent feeding failure such as double feeding of sheet materials due to the influence of the number of stacked sheet materials on the stacker.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a sheet material feeding device according to a first embodiment.

FIG. 2 is a sectional view of an essential part of the sheet material feeding device.

FIG. 3 is a schematic cross-sectional view showing a relationship between a pressure plate and an inclined surface of the sheet material feeding device.

FIG. 4 is a schematic cross-sectional view showing the relationship between the pressure plate and the inclined surface of the sheet material feeding device according to the second embodiment.

FIG. 5 is a schematic cross-sectional view showing the relationship between the pressure plate and the inclined surface of the sheet material feeding device according to the third embodiment.

FIG. 6 is a sectional view of a main part of a conventional sheet material feeding device.

FIG. 7 is a conceptual diagram showing a sheet separating process by a conventional line feed roller and a separating roller.

FIG. 8 is a conceptual diagram showing a sheet separating process by a conventional line feed roller and a separating roller.

FIG. 9 is a conceptual diagram showing a sheet separating process by a conventional line feed roller and a separating roller.

FIG. 10 is a conceptual side view showing an auxiliary separation process using an inclined surface in a conventional sheet material feeding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main body frame 1a ... Groove 1b ... Stopper 2 ... Pressure plate 2a, 2b ... Shaft 3,15,23 ... Spring 4 ... Regulation member 5 ... Line feed roller 6 ... Stacker 7 ... Inclined surface 7a, 7b ... Shaft 8 ... Separation roller 9 ... Holder 9a ... Shaft 9b ... Rib 10, 11 ... Rubber 12 ... Motors 13, 14, 16, 17, 18, Gears 19, 20 ... Arm 21 ... Shaft 22 ... Rib 22a ... Tapered part

Claims (7)

[Claims] 1. A feeding means for picking up and feeding a sheet material, a pressing means provided swingably for pushing the sheet material against the feeding means, and a feeding means fed by the feeding means. Separating means for separating the separated sheet materials one by one, and a shaker for separating in advance by abutting the sheet material sent out by the feeding means, which is arranged upstream of the separating means in the sheet material conveying direction. A sheet material feeding device comprising: a movable inclined surface; and interlocking means for changing the inclination angle of the inclined surface in association with swinging of the pressing means. 2. The interlocking means adjusts the inclination angle of the inclined surface according to the swing position of the pressing means so that the angle between the direction in which the sheet material abuts the inclined surface and the inclined surface is always constant. The sheet material feeding device according to claim 1, wherein the sheet material feeding device is changed. 3. The rocking of the pressing means is achieved by a gear train including a gear arranged at an end of each rocking center axis of the inclined surface and the pressing means, and a gear arranged between the gears. The sheet material feeding device according to claim 1, wherein the angle of the inclined surface is changed in conjunction with the sheet material feeding device. 4. The interlocking means is interlocked with the swing of the pressing means by a link mechanism in which the end portions of the arms rotatably attached to the inclined surface and the pressing means are rotatably coupled. The sheet material feeding device according to claim 1 or 2, wherein the angle of the inclined surface is changed. 5. The interlocking means is urged in the direction of the feeding means by an urging means and its swinging is restricted by a stopper, and a part of the interlocking means is formed on a cam formed in front of the end of the pressing means. The sheet material feeding device according to claim 1 or 2, wherein an angle of the inclined surface is changed by interlocking with the swing of the pressing means by a mechanism that is in contact. 6. An image forming apparatus comprising the sheet material feeding device according to claim 1. Description: 7. The image forming apparatus according to claim 6, wherein the sheet material feeding device feeds a sheet material as an image forming object or a sheet material as an image reading object.