JP2001354330A - Sheet feeding apparatus and image forming apparatus having the same - Google Patents

Abstract

(57) [Problem] To provide a sheet feeding device capable of reliably preventing double feeding of a thin sheet and reliably feeding a thick sheet. SOLUTION: A sheet S stored in a sheet storage means 1 is provided.
Are fed by the feeding means 7 and the sheets S sent by the feeding means 7 are separated and fed one by one by the separation slope 2. Then, the separation slope 2 can be moved together with the sheet S1 sent from the feeding means 7 at the time of separation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus and an image forming apparatus having the same, and more particularly to an apparatus for separating sheets by using a separation slope.

[0002]

2. Description of the Related Art Conventional image forming apparatuses such as printers, copiers, and facsimile machines are provided with a sheet feeding apparatus for feeding a sheet to an image forming section. Some sheets are separated one by one and fed to an image forming unit.

FIG. 20 is a view showing a schematic configuration of an image forming apparatus provided with such a conventional sheet feeding apparatus. In FIG. 20, reference numeral 100 denotes an image forming apparatus, and 101 denotes a horizontal sheet stacking surface 101a. The paper feed tray 102 has a separation slope provided at an end of the paper feed tray 101 in the sheet feeding direction. The separation slope 102 is provided to form an angle θ (obtuse angle) with the stacked sheets S. Have been. Reference numeral 120 denotes a position-adjustable rear-end regulating member that supports the rear end of the sheet S provided at the rear end.

Reference numeral 103 denotes a paper feed roller integrally holding a gear 103a; 105, a paper feed roller arm which rotatably holds the paper feed roller 103 and is rotatably held with respect to a drive shaft 104; Reference numeral 106 denotes a drive gear fixed to the drive shaft 104, and reference numerals 107 a and 107 d denote idler gears held by the sheet feed roller arm 105, for transmitting the drive of the drive gear 106 to the sheet feed roller 103. The drive shaft 104 is driven by a controllable drive mechanism (not shown), and the drive of the drive shaft 104 controls the start and stop of the sheet feeding operation.

Reference numeral 108 denotes a conveying roller, and 109 denotes a conveying roller which is urged by an urging means (not shown) and is in contact with the conveying roller 108 at a predetermined pressure. The sheet S sent out by the paper roller 103 is conveyed. 111 is an upper surface conveyance guide for guiding the upper surface of the sheet, and 110 is a lower surface conveyance guide for guiding the lower surface of the sheet. The sheet feeding device 100A is constituted by the sheet feeding tray 101, the sheet feeding roller 103, the sheet feeding roller arm 105, and the like.

On the other hand, in FIG. 20, reference numeral 112 denotes a photosensitive drum, reference numeral 113 denotes a toner cartridge integrally holding the photosensitive drum 112 and image developing means (not shown), and reference numeral 114 denotes a photosensitive drum surface which is exposed to form a latent image on the photosensitive drum. A laser scanner 115 to be formed is a transfer roller for transferring the toner image formed on the photosensitive drum to the sheet S by developing the latent image formed on the photosensitive drum in the toner cartridge. The photosensitive drum 112, the transfer roller 115, and the like form an image forming unit 100B.

A fixing device 116 fixes the toner image transferred by the transfer roller 115 onto the sheet S.
Reference numeral 17 denotes a discharge roller pair A for conveying the sheet S after the toner image is fixed, 118 denotes a discharge roller pair B for discharging the sheet S out of the image forming apparatus, and 119 denotes a discharge tray on which the discharged sheet S is stacked. is there.

The image forming apparatus 1 having such a configuration
When an image is formed at 00, a latent image is first formed on the surface of the photosensitive drum 112 by exposure with a laser scanner 114, and then this latent image is developed by image developing means provided in the toner cartridge 113. As a result, a toner image is formed on the surface of the photosensitive drum.

On the other hand, in parallel with this, the drive shaft 104 is rotated by receiving a drive from a drive mechanism (not shown), and this rotation is performed by an idler gear 107
gear 103a of the paper feed roller 103 via the
, Whereby the paper feed roller 103 starts rotating.

By the way, as shown in FIG. 21, the sheet feeding roller 103 is a sheet (hereinafter, referred to as a top sheet) located at the highest position among the sheets S placed on the sheet stacking surface.
1 is pressed against the upper surface of
When 03 starts rotating, a feeding force Fp due to frictional force acts on the uppermost sheet Sl. At the same time, the uppermost sheet S1 receives a frictional force Fs12 with the next transport sheet S2 immediately below it as a resistance.

As a result, the uppermost sheet S1 abuts against the separation slope 102 and the reaction force R from the separation slope 102.
1 and the leading end is bent, and thereafter, the sheet feeding roller 103 is rotated, so that the sheet S
1 will be advanced in a bent state with its tip abutting on the separation slope. The next transport sheet S2
Receives the frictional force Fs23 from the sheet S3 immediately below the sheet S3, does not advance with the uppermost sheet S1, and is not multi-fed.

Then, in this way, the paper feed roller 103
The uppermost sheet S1 separated and sent out by the separation slope 102 is conveyed by the rotation of the conveying roller 108 and the conveying roller 109 shown in FIG. 20, and is sent to the nip between the photosensitive drum 112 and the transfer roller 115.

Thereafter, the toner image formed on the photosensitive drum is transferred to the transfer roller 11 on the sheet S1 fed to the nip between the photosensitive drum 112 and the transfer roller 115.
5, the sheet S1 to which the toner image is further transferred is conveyed to the fixing device 116. After the toner image is fixed in the fixing device 116, the sheet S1 is discharged out of the apparatus main body 100C by the sheet discharge roller pair Al17 and the sheet discharge roller pair B118, and is stacked on the sheet discharge tray 119. .

[0014]

In such a conventional sheet feeding apparatus and an image forming apparatus having the same, as described above, the sheet S on the separation slope 102 is formed to prevent the double feeding of the sheet. It depends on the resistance and the friction between the sheets.

Therefore, for example, when a sheet is replenished before the last replenished sheet is used, the friction coefficient between the sheets at the boundary between the new and old sheets, that is, at the replenishment surface, is determined by the friction coefficient between the sheets at the other surface. If it is lower than the coefficient,
Sheet separation is performed only by the deformation resistance of the sheet on the separation slope 102, and as a result, double feed in the vicinity of the replenishing surface frequently occurs, particularly for a sheet such as a thin paper sheet having a low stiffness.

Here, for example, the sheet feeding roller 103 and the separation slope 10 are provided so as to efficiently prevent double feeding of thin paper.
There is a case where the distance from the paper 2 is set to be short. In this case, the double feed of the thin paper can be prevented, but the force required for feeding the thick paper becomes insufficient, and the paper feeding may fail. is there.

Accordingly, the present invention has been made in view of such a situation, and a sheet feeding apparatus capable of reliably preventing double feeding of thin sheets and reliably feeding thick sheets. And an image forming apparatus provided with the same.

[0018]

SUMMARY OF THE INVENTION According to the present invention, there is provided a sheet feeding means for feeding a sheet in contact with a sheet stored in a sheet storing means, and separating the sheets fed by the sheet feeding means one by one. A sheet feeding device having a separation slope for feeding the sheet in the sheet feeding device, wherein the separation slope is movable relative to the sheet feeding means.

According to the present invention, there is provided a sheet feeding means for feeding a sheet in contact with a sheet stored in a sheet storing means, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. Wherein the separation slope is configured to be movable along the sheet advancing direction along with the sheet fed from the sheet feeding means.

The present invention is characterized in that the separation slope is provided so as to be able to advance and retreat in the sheet advancing direction within a plane including a sheet contact surface with which the leading end of the sheet abuts on the separation slope.

According to the present invention, the separation slope is provided at a sheet feeding side end of a sheet storage portion of the sheet storage means, and the separation slope is moved to a fixed slope reference plane parallel to the sheet contact surface. It is characterized by being attached as possible.

According to the present invention, when the separation slope moves along the traveling direction of the sheet along with the movement of the fed sheet, the separation slope is set to be in contact with the sheet on the separation slope in an initial state. It is characterized in that the sheet contact surface moves gradually away from the plane including the contact surface in a direction parallel to the plane and in a direction opposite to the side where the sheet feeding means is disposed.

According to the present invention, the separating slope is provided at an end of the sheet storage section of the sheet storage section on the sheet sending side, and the separation slope is moved from a plane including the sheet contact surface in a sheet advancing direction. A slope reference surface that is inclined in a direction away from the sheet feeding means, and the separation slope is provided on a slope holding member movable along the slope reference surface, and the separation slope is brought into contact with the sheet by the slope holding member. The sheet is moved in a state parallel to a plane including the surface and gradually away from the plane in a direction opposite to the side where the sheet feeding means is disposed.

According to the present invention, the slope reference surface is composed of two parallel and stepped surfaces, and the slope holding member for holding the separation slope slides on both of the two slope reference surfaces. It is characterized by the following.

The present invention is characterized in that the separation slope starts moving from an initial position together with the sheet when a predetermined force is applied by the sheet fed from the sheet feeding means.

The present invention is characterized in that when the separating slope is moved by the force from the sheet, it returns to the initial position by its own weight.

The present invention is characterized in that it has an elastic member for returning the separation slope to an initial position at the start of movement.

According to the present invention, a plurality of the separation slopes are arranged in the width direction of the sheet, and the separation slope is brought into contact with the sheet at an initial position when the separation slope starts moving between the plurality of separation slopes. A fixed slope member fixed substantially parallel to the surface and recessed from the sheet contact surface.

The present invention is characterized in that the resistance applied to the leading end of the sheet separated from the surface of the fixed slope member is smaller than the resistance applied from the separation slope.

The present invention is characterized in that the fixed slope member is disposed so as to gradually project from the sheet contact surface of the separation slope when the separation slope moves with the sheet from the initial state. And

[0031] The present invention is characterized in that a regulating means is provided for holding the separation slope moved to a predetermined position together with the sheet.

The present invention is characterized in that the sheet storage means is detachably stored in the apparatus main body, and the holding operation of the regulating means is released in conjunction with the taking-out operation of the sheet storage means. .

The present invention is characterized in that the sheet storage means uses a lifter-type middle plate that can move up and down while maintaining the same posture angle.

The present invention is characterized in that the separation slope and means for movably supporting the separation slope are provided on a front door unit which opens and closes when paper is supplied.

The present invention is characterized in that the lifter type intermediate plate is inclined such that the side on which the separation slope is disposed is positioned vertically upward.

According to the present invention, there is provided a sheet feeding means for feeding a sheet in contact with a sheet stored in a sheet storing means, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. Wherein the separation slope is configured so that the sheet fed by the sheet feeding means abuts and bends.

The present invention is characterized in that the separation slope is formed of a flexible plate-like member.

According to the present invention, there is provided a sheet feeding means for feeding a sheet in contact with a sheet stored in a sheet storing means, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. And wherein the separation slope can be moved by a manual operation in a state parallel to a direction in which the separation slope approaches or separates from the sheet feeding means.

According to the present invention, a sheet holding member for holding a sheet in the sheet storage means is connected to the separation slope, and the sheet holding member is provided so as to be movable with the movement of the separation slope. Features.

According to the present invention, there is provided a guide member disposed downstream of the separation slope for transferring a sheet sent out by the sheet feeding means from the separation slope to a conveying path. It is characterized in that it is moved in conjunction with the movement of.

[0041]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a view for explaining the structure of a sheet feeding apparatus according to a first embodiment of the present invention, and FIG.
It is a 1 arrow view. 1 and 2, reference numeral 1A denotes a sheet feeding device, 1 denotes a sheet feeding tray which is a sheet storage means provided with a fixed sheet stacking surface 1b configured to be higher in a sheet feeding direction, and 2 denotes a sheet feeding device. The separation slope 2 is provided at the end of the sheet feeding direction of the tray 1, and the separation slope 2 is provided at the sheet sending side end of the sheet storage unit that stores the sheets of the paper feed tray 1. Are arranged so as to form an angle θ with respect to the stacked sheets S.

Reference numeral 3 denotes a slope holding member for holding the separation slope 2, and reference numeral 4 denotes a sliding roller rotatably attached to the slope holding member 3. In the present embodiment, two sliding rollers 4 are attached to the slope holding member 3, but the number of the sliding rollers 4 may be any number as long as the slope holding member 3 can move smoothly.

Reference numeral 5 denotes a fixed slope reference plane provided at the end of the sheet feeding tray 1 on the sheet feeding direction side and provided in parallel with the sheet contact surface with which the sheet on the separation slope 2 contacts. Numeral 3 can move along the slope reference surface 5 via the sliding roller 4. Thus, the separation slope 2 can move forward and backward in the sheet traveling direction.

Reference numeral 6 denotes a slope spring which is an elastic member, 3a is provided on the slope holding member 3, and a spring receiving movable boss holding one end of the slope spring 6; A spring receiving fixing boss holding the other end. Reference numeral 3b denotes a retaining boss that prevents the slope holding member 3 from sliding off the slope reference surface 5 together with the spring receiving movable boss 3a. The spring receiving movable boss 3a and the retaining boss 3b are inserted through guide holes 5a formed in the slope reference surface 5, respectively.
In addition, the retaining boss 3b is prevented from coming off by a flange formed on the boss 3b. In addition, a wide opening is formed in the upper part of the guide hole 5a so that a flange portion formed on each boss can be inserted therethrough.

FIG. 5 shows a state in which the slope holding member 3 is at an initial position before the sheet feeding operation is started. In this state, the slope spring 6 holds the slope holding member 3 at a predetermined position. Pulling force Fl. At this time, the spring receiving movable boss 3a and the retaining boss 3b are
As shown in FIG. 5, the lower end of the guide hole 5a formed in the slope reference surface 5 is in contact with each other, whereby the slope holding member 3 is pulled to the slope reference surface 5 by the slope spring 6 with a predetermined force Fl. It has been held.

Reference numeral 7 denotes a sheet feeding roller as sheet feeding means integrally holding a gear (not shown), 8 denotes a drive shaft, 9 denotes a sheet feed roller 7 rotatably held, and A feed roller arm 10 rotatably held is provided with drive gears 11a, 11b, 11c fixed to the drive shaft 8,
Reference numeral 11d denotes an idler gear held by the paper feed roller arm 9 so as to transmit the drive of the drive gear 10 to the paper feed roller 7. The drive shaft 8 is driven by a controllable drive mechanism (not shown). As a result, the start and stop of the sheet feeding operation are controlled.

Reference numeral 12 denotes a transport roller which rotates by being driven by a drive unit (not shown). Reference numeral 13 denotes a transport roller which is in contact with the transport roller 12 at a predetermined pressure by a biasing means (not shown). 13, the sheet fed is conveyed. 14
Is an upper surface transport guide for guiding the upper surface of the sheet, and 15 is a lower surface transport guide for guiding the lower surface of the sheet. In this embodiment, the arrangement of the paper feed roller 7 and the angle θ formed by the separation slope 2 with respect to the sheet (bundle) S are set to be suitable for preventing the double feeding of thin paper. Further, in order to transfer the sheet to a conveyance path composed of an upper surface conveyance guide 14 and a lower surface conveyance guide 15 for vertically conveying the sheet, the separation slope 2 is used.
In order to secure the angle θ, the sheet stacking surface 1b is formed obliquely so that the sheet feeding side is higher.

Next, the sheet separating operation of the sheet feeding apparatus 1A thus configured will be described. When the sheet feeding is started, the drive shaft 8 and the drive gear 10 are driven by a drive mechanism (not shown) and rotate. This rotation is performed by the idler gears 11a, 11b, 1
The light is transmitted to the paper feed roller 7 via 1c and 11d, and the paper feed roller 7 starts rotating.

Here, since the paper feed roller 7 is in pressure contact with the upper surface of the uppermost sheet Sl of the sheets S placed on the sheet stacking surface, the rotation of the paper feed roller 7 causes the uppermost sheet Sl Is fed by frictional force.

If the sheet to be fed now is a thin sheet, the setting of the feed roller 7 and the separation slope 2 causes the sheet shown in FIG.
As shown in FIG. 7, even if the feeding force is small, the uppermost sheet S1 is deformed along the separation slope 2, and is advanced by being guided by the upper surface transport guide 14 and the lower surface transport guide 15, and then the transport roller 1
The sheet 3 is conveyed to an image forming apparatus (not shown) by the conveying roller 12.

On the other hand, when the sheet is a stiff cardboard, the leading end of the uppermost sheet S1 does not deform along the separation slope 2 at first due to the setting of the sheet feeding roller 7 and the separation slope 2, and the sheet is further fed afterward. When the value of the feeding force increases due to the rotation of the paper roller 7, the feeding force acts in a direction to push up the slope holding member 3 due to the stiffness of the sheet S1.

Thereafter, if the component force of the feeding force in the direction parallel to the separation slope 2 exceeds a predetermined force F1 applied to the slope holding member 3 by the slope spring 6 in the initial state, the slope The holding member 3 starts to move upward. Since the contact between the slope holding member 3 and the slope reference surface 5 is rolling contact by the sliding roller 4, the frictional force between the two may be considered to be very small.

When the slope holding member 3 starts moving upward as described above, the leading end of the sheet is strongly in contact with the separation slope 2 held by the pushed-up slope holding member 3 and is shown in FIG. As described above, as the slope holding member 3 (separated slope 2) moves, the slope holding member 3 is lifted upward. As a result, the uppermost sheet S1 is bent and deformed, and
Since the contact angle between the leading end of the sheet and the separation slope 2 becomes gentle and slipping easily occurs, the sheet is fed along the sheet contact surface of the separation slope 2.

As described above, when the sheet is fed, the separating slope 2 is moved together with the sheet fed from the sheet feeding roller 7, that is, the separating slope 2 is moved relatively to the sheet feeding roller 7. The position of the sheet feeding roller 7 and the separation slope 2 that can reliably prevent the double feeding of thin paper by making it possible.
And a thick sheet can be fed.

Further, it is possible to reduce the paper feeding force required at the time of feeding thick paper, and to reduce the load on the driving source. further,
The above-mentioned effect can be obtained by using a mechanism having a small occupied space.

Further, by using the sliding roller 4, the operation threshold value of the slope holding member 3 can be set to the slope reference surface 5 of the frictional force.
Is not affected by the frictional force due to the vertical drag component, and is determined only by the initial force of the slope spring 6, so that the operation can be more reliably separated between thin paper and thick paper. After the sheet is separated and sent out, the separation slope 2 is returned to the initial position when the movement is started by the slope spring 6. In order to return the separation slope 2 to the initial position, the separation slope 2 may be returned with its own weight or weight without using the slope spring 6.

Next, a second embodiment of the present invention will be described.

FIG. 5 is a diagram showing a configuration of the sheet feeding apparatus according to the present embodiment. In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts.

In the drawing, reference numeral 30 denotes a sheet feeding tray, reference numeral 20 denotes a separation slope provided at a sheet feeding side end of a sheet storage portion for storing sheets of the sheet feeding tray 1, and reference numeral 21 denotes a separation slope 20. Slope holding member for holding, 2
Reference numeral 2 denotes a slope reference surface that slidably holds the slope holding member 21 and is inclined in a direction away from the paper feed roller 7.
The slope reference surface 22 is formed so as to incline in a direction away from the sheet feeding roller 7 as the sheet advances in the sheet advancing direction from a plane including the sheet contact surface 20a with which the sheet on the separation slope 20 contacts. 20 sheet contact surfaces 2
It forms an angle of with respect to 0a.

Reference numeral 23 denotes a slope spring which pulls the slope holding member 21 at a predetermined force F2 at the initial position shown in FIG.
21a is a spring receiving movable boss provided on the slope holding member 21 and holding one end of the slope spring 23. 30a is a spring receiving fixing boss provided on the sheet feeding tray 30 and holding the other end of the slope spring 62. , 21b are spring receiving fixing bosses 21a.
In addition, it is a retaining boss for retaining the slope holding member 21 slidable with respect to the slope reference surface 22. In addition,
The structure for attaching the spring receiving movable boss 21a and the retaining boss 21b to the slope reference surface 22 is the same as the configuration described in the first embodiment.

Reference numeral 24 denotes a latch arm pivotally supported by the paper feed tray 30. The latch arm 24 is normally urged counterclockwise by an urging means (not shown) to
The front end protrudes from a cutout portion 22a formed at the upper end of the first. Reference numeral 21c is a locking hole provided on the sliding surface of the slope holding member 21 to lock the distal end of the latch arm 24.

Reference numeral 25 denotes a latch release portion which is integral with the latch arm 24 and protrudes from a latch release portion hole 27 formed on the side wall of the sheet feeding tray 30. In addition, 2
Reference numeral 6 denotes a downstream guide member that is fixed to the paper feed tray 30 and guides the sheet fed by the paper feed roller 7.

Next, the sheet separating operation of the sheet feeding apparatus 1A thus configured will be described.

When a thin sheet is fed, the uppermost sheet S1 is separated from the separation slope 2 by the setting of the sheet feeding roller 7 and the separation slope 20 even if the feeding force is small, as in the first embodiment.
It is conveyed while deforming along 0. At this time, the separation slope 20 (slope holding member 21) is connected to the slope spring 23.
Is stopped by the action of the initial force F2.

On the other hand, when a thick sheet is fed, the leading end of the uppermost sheet S1 does not deform along the separation slope 20 at first due to the setting of the sheet feeding roller 7 and the separation slope 20, and after that, the sheet is further fed. When the value of the feeding force increases due to the rotation of the roller 7, the feeding force acts in a direction to push up the slope holding member 21 due to the stiffness of the sheet S1.

Thereafter, when the feeding force increases, a component force [Fs · cos (θ + ψ)] of the feeding force is applied to the slope holding member 21 by the slope spring 23 in the initial state. Will be exceeded. Thereby, the slope holding member 21 and the separation slope 20 are connected to the slope spring 2.
3 and the angle formed by the slope reference surface 22 with respect to the sheet S is (θ + ψ), so that it is moved to the upper right in the figure together with the sheet S1 as shown in FIG. I do.

When the paper is thus fed, the separation slope 2
0 is moved together with the sheet fed from the sheet feeding roller 7, so that the position of the sheet feeding roller 7 and the angle of the separation slope 2 which can surely prevent the double feeding of thin sheets can be adopted. Paper feeding can be enabled.

In the present embodiment, the feeding force F
The component force [Fs · cos (θ + ψ)] of the separation slope 20
Force [Fs · co] in the direction (angle to the sheet: θ)
s (θ)], the sheet can be fed with a smaller force than in the first embodiment.

When thick paper is fed so that the separation slope 20 must be largely moved to feed the paper, the slope holding member 21 moves to the position shown in FIG. Here, when the slope holding member 21 moves to this position, it is held by the regulating means. The restricting means includes a locking hole 21c provided in the slope holding member 21 and a latch arm 2 provided on the sheet feeding tray 30 side so as to be lockable in the locking hole 21c.
4 is provided. By this regulating means, the slope holding member 2
1 is held at the position shown in FIG.

As a result, the distance between the contact portion between the sheet feeding roller 7 and the sheet S and the contact portion between the sheet S and the separation slope 21 is
In FIG. 5, X was changed to X + as shown in FIG.
ΔX, that is, the distance between the feed roller 7 and the separation slope 21 increases. Thereby, the thick sheet is more easily bent, and the thick sheet can be fed even in a state where the slope holding member 21 is fixed.

As described above, according to the present embodiment, the moving direction of the separation slope 20 defined by the slope reference plane 22 can be set to be gentler than the angle θ of the separation slope. Therefore, the moving direction of the leading end of the sheet becomes a shallow angle. For this reason, the load applied to the initial movement is reduced, and a thicker sheet is easily fed.

Further, since the slope holding member 21 is held by the latch mechanism of the restricting means, the slope holding member 21 does not slide every time a thick sheet is fed, so that durability and quietness are improved. Is improved. Further, since the moving direction of the separation slope 20 includes a movement component in the sheet stacking direction, even if the sheet tip touches the separation slope 20 in the initial state, the operation is not hindered, and the operation is more stable. It is possible to operate.

In FIGS. 6 and 7, reference numeral 29a denotes a release cam provided on the inner wall 28 of the image forming apparatus, and 29b denotes a latch guide provided on the inner wall 28. Here, the release cam 29a is connected to the slope holding member 2 by the latch arm 24.
2 to release the holding of the release cam 2.
9a is a paper feed tray 30 detachably provided in the apparatus main body.
When taking out from the apparatus main body, the latch arm 24 is rotated clockwise while coming into contact with the latch release section 25. When the latch arm 24 rotates clockwise in this manner, the holding of the slope holding member 22 by the latch arm 24 is released.

In this embodiment, it is obvious that the effects unique to the present invention can be obtained even if the latch arm 24 is omitted. In place of the latch arm 24, a smooth braking may be applied using a plastic member or a damper at the top dead center of the operation of the slope holding member. Further, as in the first embodiment, the separation slope 20 is not used to return the separation slope 20 to the initial position without using the slope spring 23.
The weight may be returned with its own weight or weight.

Next, a third embodiment according to the present invention will be described.

FIG. 8 is a schematic sectional view of the sheet feeding apparatus according to this embodiment. FIG. 9 is a diagram illustrating a state immediately after starting the sheet feeding operation in the sheet feeding apparatus according to the present embodiment. FIG. 10 is a perspective view for explaining the situation of the inclined member arrangement surface of the sheet feeding tray in the present embodiment. In the above figures, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts.

In FIG. 8, reference numeral 51 denotes a sheet stacking surface 51a.
A paper tray (paper cassette) equipped with
Steps are provided, each having the same configuration. Reference numeral 52 denotes an optional path provided in the paper feed tray 51,
Reference numeral 53 denotes a separation slope disposed at a side end of the sheet feeding tray. In FIG. 8, the separation slope 53 is in an initial position before the sheet feeding operation.

Reference numeral 54 denotes a slope holding member which holds the separation slope 53 and is movably held with respect to the sheet feeding tray 51. In the present embodiment, no biasing means or the like is provided on the slope holding member 54, and the separation slope 53 is not provided.
And the weight of the slope holding member 54 to return to the initial position shown in FIG.

Reference numerals 55a and 55b denote posture determining pins provided on the slope holding member 54, 56 denotes a lower slide surface provided on the paper feed tray 51, and 57 denotes a paper feed tray 5
1 and is an upper slide surface which is a step and is substantially parallel to the lower slide surface 56. The slope holding member 54 is slidable on both the lower slide surface 56 and the upper slide surface 57, and its posture is provided on both the lower slide surface 56 and the upper slide surface 57 (not shown). Slot and posture determination pins 55a, 5
5b.

Reference numeral 61 denotes a support slope which is fixedly disposed at a position farther from the sheet stacking area (sheet storage portion) than the separation slope 53 in FIG. 8 and is substantially parallel to the separation slope 53. . The support slope 61 is made of a material (material) that applies a lower conveyance resistance to the sheet leading end than the separation slope 53.

By providing the two-stage slide surface, the occupied volume is reduced more than the slide member shown in FIG. 5, and as a result, the option path 52 is extended in the vertical direction as shown in FIG. It is possible to arrange.

Reference numeral 58 denotes a paper feed roller. Reference numeral 59 denotes a paper feed roller 58 which is rotatably held near one end by an arm shaft 60, holds the paper feed roller 58 near the other end, and has a paper feed roller 5 therein.
8 is a sheet feeding roller arm unit holding driving means for transmitting driving to the sheet feeding roller 8.

In FIG. 8, reference character B denotes an optional feeder in the present embodiment, reference numeral 62 denotes an optional transport roller, reference numeral 63 denotes an optional transport roller, and reference numeral 64 denotes a feeder mounted on the optional feeder B. An optional lower surface paper feed guide that guides the lower surface of the leading edge of the sheet fed from the paper tray 51, and 65 guides the upper surface of the leading edge of the sheet fed from the paper tray 51 mounted on the optional feeder B This is an optional upper surface paper feed guide.

S1 in FIG. 9 indicates a fed sheet.

FIG. 10 is a view showing the arrangement of the separation slope 53 and the support slope 57 in the sheet width direction in the present embodiment. In FIG. 10, the separation slopes 53a and 53b (the left and right sides) are arranged in pairs in the sheet width direction. ) And the separation slope (right). As shown in the drawing, in the present embodiment, a plurality of separation slopes and a support slope 61 are arranged at intermediate positions between the separation slopes.

The surface of the support slope 61 has a lower coefficient of friction than the surfaces of the separation slope (left) 53a and the separation slope (right) 53b and is configured to be slippery. When the separation slope (left) 53a and separation slope (right) 53b are at the lower position (initial position), the support slope 61 is at a position retracted from the separation slope (left) 53a and separation slope (right) 53b. (See FIG. 11A), and the separation slope (left) 53
a, When the separation slope (right) 53b moves upward, the support slope becomes a position protruding toward the paper stacking range side from the separation slope (left) 53a and the separation slope (right) 53b.

Next, the sheet separating operation in the sheet feeding apparatus thus configured will be described.

By the rotation of the paper feed roller 58, the paper feed force due to the frictional force with the paper feed roller 58 acts on the uppermost sheet, and the uppermost sheet starts to move in the right hand direction in the figure. The leading edge of the sheet comes into contact with the separation slope 53 and starts to bend along the separation slope 53. At this time, the uppermost sheet and the other sheets are separated. Thereafter, as the paper feed roller 58 continues to rotate, the leading end of the sheet is fed to the nip between the rotating transport roller 12 and the transport roller 13, and is transported to an image forming apparatus (not shown) by the transport force of the transport roller pair. .

When the rigidity of the fed sheet is high,
Since the force applied to the separation slope 53 increases, the sheet holding force applied by the sheet feeding roller 58 increases the slope holding member 54.
The separation slope (left) 53a and the separation slope (right) 53b are pushed up. At this time, the slope holding member 54 is guided by the lower slide surface 56 and the upper slide surface 57 and moves along the slide direction defined by both.

As shown in FIG. 11A, when the movement of the separation slope (left) 53a and the separation slope (right) 53b exceeds a predetermined amount, the leading end of the sheet is moved to the separation slope (left) 53a and the separation slope (right). A) It comes into contact with the support slope 61 projecting from 53b. Since the surface of the support slope 61 is configured to be more slippery than the separation slope (left) 53a and the separation slope (right) 53b, the center of the leading end of the highly rigid sheet slides out along the support slope 61. Thus, the advancing direction of the sheet is the support slope 61 contact area in the support slope 61 contact area, and the separation slope contact area is the slide surface direction in the separation slope contact area. As a result, as the leading edge of the sheet advances, the separation slope (left) 53a, the separation slope (right) 53
b, the degree of abutting of the sheet leading end with respect to b is reduced,
The leading end of the sheet gradually moves in the direction of the support slope 61.

When a surface having a friction coefficient significantly smaller than the others is included in the stacked sheet bundle, several sheets immediately above the low friction surface are interlocked with the operation of the feed roller 58. May cause back and forth movement. FIG. 11 is a view showing this state. SL in FIG. 11 is the above-mentioned low friction surface. Even in such a case, the range of the forward and backward movement is determined by the support slope 61, so that the sheet can be fed without causing multiple feeding.

In this embodiment, since only the own weight is applied to the slope holding member 54, even when the sheet end having high rigidity lifts the separation slope upward, the same resistance force is always exerted on the separation slope ( Left) 53a, separation slope (right) 53
b.

With the above configuration, the following effects can be obtained. (1) By providing a plurality of slide surfaces, the space on the back surface can be increased, and as a result, an optional path can be easily provided. (2) By providing the support slope at the center, it is possible to change the direction of the cardboard quickly, and to improve the cardboard feeding performance. (3) The same resistance can be applied to the leading edge of the paper irrespective of the amount of rise of the sliding separating slope by using the sliding separating slope which is urged in the moving direction only by its own weight. It is also possible to prevent some scratches or the like from occurring on the surface.

Next, a fourth embodiment according to the present invention will be described.

FIG. 12 is a schematic sectional view of a large-capacity sheet feeding apparatus according to this embodiment. FIG. 13 is a diagram illustrating a state in which the front door is opened in the sheet feeding apparatus according to the present embodiment. FIG. 14 is a conceptual diagram illustrating a loading table vertical movement mechanism according to the present embodiment.

In FIG. 12, C indicates a large-capacity sheet feeding apparatus according to the present embodiment, D below it indicates a large-capacity tray mechanism main body, and E indicates when a sheet is supplied. 2 shows a front door unit to be rotated. In the figure, reference numeral 71 denotes a paper feeding roller, 72 denotes a paper feeding roller arm unit, and the paper feeding roller arm unit incorporates driving means for transmitting drive to the paper feeding roller 71, and 73 denotes a conveying roller. Reference numeral 74 denotes a transport roller that faces the transport roller and is urged toward the transport roller 73 by a pressing unit (not shown).

In this embodiment, two pairs of transport rollers are arranged in a direction perpendicular to the plane of the drawing. Reference numeral 75 denotes a transport path, which faces a paper inlet of an image forming apparatus (not shown). Reference numeral 76 denotes a sheet lifter that can be moved up and down under control. The sheet lifter 76 has a sheet loading surface that is inclined such that the transport direction rises vertically with respect to a horizontal plane. 77 is a lift motor for controlling the vertical movement of the seat lifter 76, and 78 is a drive pulley directly connected to the lift motor. In this embodiment, the drive pulley 78 is connected to the lift motor 7 for explanation.
Although it is directly connected to 7, even if it is connected via a drive system, it does not depart from the spirit of the invention. 79 is a lifter drive belt, and 80 is an idler pulley B. 81 is a regulating means for holding the idler pulley B80, 82 is a positioning column for determining the moving direction of the sheet lifter 76,
Reference numeral 83 denotes a slide bearing fixed to the seat lifter 76.

In this embodiment, two pairs of positioning pillars 82, slide bearings 83, and idler pulleys B 80 are disposed in a direction perpendicular to the paper surface. It is a member. Reference numeral 85 denotes a separation slope provided on the front door unit E. In the present embodiment, two separation slopes are arranged in a direction perpendicular to the paper surface. Reference numeral 86 denotes a slope holding member that holds the separation slope 85, and the slope holding member 86 is positioned by the same method as the slope holding member 54 in the third embodiment.

FIG. 13 shows a state where the front door unit is rotated. In the figure, reference numeral 87 denotes a front door rotation shaft provided on the large capacity tray mechanism main body D, and reference numerals 88 and 89 denote bearing members H and L held by the front door unit E. Also, in FIG.
b is the transport rollers L and R. 85a and 85b are separation slopes L and R. FIG. 14 shows a driving means of the seat lifter 76 in the present embodiment.
Reference numerals 80a and 80b denote idler pulleys B (L) and B (R), 90a and 90b denote idler pulleys B (L) and B (R), and 9
Reference numerals 1a and 91b denote idler pulleys B (L) and idler pulleys B (R), which are idler pulleys for determining the path of a lifter drive belt 79 for driving the sheet lifter 76. Reference numerals 92a and 92b denote a part of the sheet lifter, which is a belt fixing member (L) and a belt fixing member (R) for fixing a predetermined position of the lifter driving belt 79. By these fixing means, the seat lifter 76 can smoothly move up and down by the movement of the belt. 82a,
82b is a positioning column (L) and a positioning column (R), and 83a and 83b are a slide bearing (L) and a slide bearing (R) fixed to the seat lifter 76.

Next, the sheet feeding operation in the large-capacity sheet feeding apparatus thus configured will be described.

The seat lifter 76 can be moved up and down by rotation control of a lift motor 77 by the seat lifter driving mechanism shown in FIG. The position control of the seat lifter is performed by combining this with a top surface detection unit and a front door open / close detection unit (not shown).

When the front door unit E is opened, this is detected by the front door detecting means, and the lift motor 77 is opened.
Is rotated in the direction in which the sheet lifter descends and is stopped at a predetermined position, so that the large-capacity sheet feeding apparatus according to the present embodiment takes a posture to accept paper supply by the user. At this time, it is easy to release the contact with the sheet by rotating the sheet supply roller arm 72 upward as shown in FIG. 13 by a simple mechanism. Further, in the present embodiment, since the sheet lifter 76 is configured to have a surface that is lowered in the paper supply direction, replenishment can be performed by dropping a sheet bundle. When the replenishment is completed and the front door unit E is closed, the seat lifter control means detects the closed state by the front door detection means, rotates the lift motor 77 in a direction to raise the seat lifter 76, and The sheet lifter 76 is raised until it is detected that the uppermost surface of the stacked sheets has reached a predetermined height.

The sheet feeding operation is performed as follows.
First, a sheet feeding roller arm 72 is driven by a driving mechanism (not shown).
Is rotated for a certain period of time, whereby the paper feed roller 71 that contacts the uppermost sheet also rotates for a certain period of time.
Thereby, the sheet feeding force is applied to the uppermost sheet, and the sheet advances rightward in the drawing. At this time, when the sheet comes into contact with the separation slopes 85a and 85b and bends, the uppermost sheet and the other sheets are separated using the force required for the bending as a threshold value. When the thick paper is fed, the separation slope 85 moves along the sliding direction of the slope holding member 54 without being affected by the waist of the paper, as in the above-described embodiments. It is possible to send.

In the present embodiment, the separation slope 85
a, 85b and the transport rollers 74a, 74b are provided on the front door unit side, so that the view of the space above the sheet lifter 76 is greatly opened when the front door unit is opened, and the sheet stacking operation and the replacement of the paper feed roller 71 are performed. The configuration is such that the operation, the stacking paper size changing operation, and the like can be more easily performed.

The structure of the separation section using the separation slopes 85a and 85b may be any of the first to third embodiments.

Under the above configuration, the following effects can be obtained. (1) By inclining the sheet lifter in the direction in which the upstream side in the sheet feeding direction is lowered, it is possible to facilitate the work of replenishing the sheet, and to make the separation slope portion and the front end regulating member surface of the sheet on the lifter substantially parallel. And the step can be easily managed, which is effective for stabilizing the sheet feeding performance. (2) By providing the separation slope on the front door unit side, it is possible to more easily perform the sheet stacking operation, the sheet feeding roller 71 replacing operation, the stacking paper size changing operation, and the like. (3) A space can be provided near the upper surface of the large-capacity sheet feeding device by adopting the sheet feeding roller arm structure and tilting the sheet lifter. This makes it possible to efficiently arrange the drive mechanism for vertically moving the seat lifter near the upper surface. This makes it possible to efficiently arrange electric components and optimally arrange a lifter vertical movement mechanism.

Next, a fifth embodiment of the present invention will be described.

FIG. 15 is a diagram showing a configuration of the sheet feeding apparatus according to the present embodiment. In FIG. 1, FIG.
The same reference numerals indicate the same or corresponding parts.

In FIG. 15, reference numeral 31 denotes a sheet feeding tray detachable from the apparatus main body, 32 denotes a separation slope, 33 denotes a sheet holding member which holds the separation slope 32 and is slidably provided on the sheet feeding tray 31, and 31a. Is the sheet holding member 3
3 is a stopper for slidably positioning the vertical position of the sheet feeder 3, and the stopper 31 a is a part of the sheet feed tray 31. By the sliding movement of the sheet holding member 33, the separation inclined surface 32 moves in a direction to approach or separate from the sheet feeding roller 7 with the contact surface of the sheet being parallel.

Reference numeral 34 denotes a trailing end regulating member that determines the position of the upstream end face in the sheet feeding direction, and reference numeral 33d denotes a trailing end positioning hole that determines the position of the trailing end regulating member 34. A plurality of members 33 are provided,
The rear end regulating member 34 can be fixed and positioned by the user's hand in the above-described arbitrary rear end positioning hole 33d according to the sheet size to be used.

Reference numeral 35 denotes a paper feed roller arm which rotatably holds the paper feed roller 7 at one end thereof and is rotatably held about a drive shaft 8, and 36 supplies a driving force of the drive gear 10. This is an idler gear train for transmitting to the paper roller 7.

A guide 37 guides the lower surface of the sheet conveyed along the separation slope 32, is rotatable around the shaft 13a of the conveying roller 13, and is rotated counterclockwise by a biasing means (not shown). The urged lower guide member 38 is an upper guide member for guiding the upper surface of the sheet 39.
A lower guide block 39 serves as a guide for the lower surface of the sheet downstream of the conveyance roller 12, and a boss member 39 a that defines a rotation range of the lower guide member 37.

On the other hand, 33a and 33b are the sheet holding members 3
3, first and second knobs protruding from an upper end portion 33B protruding from the upper end of the separation slope holding portion 33A; 33c are positioning hooks formed at the end of the upper end portion 33B;
Reference numerals 1 and 31b2 denote two positioning holes provided on the sheet feeding tray 31, and the positioning hooks 33c are selectively locked.

Here, in this embodiment, the position of the sheet holding member 33 is manually switched according to the thickness of the sheet to be fed. That is, when feeding a thin sheet, the positioning hook 33c is locked in the first positioning hole 31b1 as shown in the figure, so that the distance between the feed roller 7 and the top end of the uppermost sheet is shortened. ing. By shortening the distance between the sheet feeding roller 7 and the top end of the uppermost sheet, a thin sheet can be reliably separated.

On the other hand, when feeding a thick sheet, the first and second knobs 33 are pulled out after the sheet feeding tray 31 is pulled out.
A, 33b is first pulled out of the positioning hook 33c from the first positioning hole 31b1 as shown in FIG. 16, and then the sheet holding member 33 (separation) is held while the first and second knobs 33a, 33b are being picked up. The slope 32) is moved in a direction away from the paper feed roller 7.

Finally, as shown in FIG. 17, the positioning hook 33c is locked in the second positioning hole 31b2, so that the distance between the sheet feeding roller 7 and the top end of the uppermost sheet is increased. And, as described above, the paper feed roller 7
By increasing the distance between the
Thick sheets can be reliably separated.

When the positioning hook 33c is locked in the second positioning hole 31b2, the first knob 33a moves to a position away from the lower surface guide member 37. Here, when the first knob 33a moves in this manner, the lower surface guide member 37 is moved by the urging force of the urging means.
As shown in FIG. 17, it rotates to a position where it comes into contact with the first knob 33a. That is, the position of the lower surface guide member 37 switches in conjunction with the movement of the separation slope 32.

Next, the sheet separating operation of the sheet feeding apparatus 1A thus configured will be described.

When the paper feeding is started, the drive shaft 8 and the drive gear 10 are driven by a drive mechanism (not shown) and rotate.
This rotation is transmitted to the paper feed roller 7 via the idler gear 36 in the paper feed roller arm 35, and the paper feed roller 7 starts rotating. Here, since the paper feed roller 7 is in pressure contact with the upper surface of the uppermost sheet Sl placed on the sheet stacking surface, the feeding force due to the frictional force is applied to the uppermost sheet Sl by the rotation of the paper feed roller 103. Works.

If the sheet is thin paper, the sheet holding member 33 is set in the state shown in FIG.
After being deformed along 2 and guided by the upper surface guide 38 and the lower surface guide 37, the sheet is conveyed to an image forming apparatus (not shown) by the conveying rollers 13 and the conveying rollers 12.

On the other hand, when feeding a thick sheet, first, after taking out the sheet feeding tray 31, the first and second knob portions 33a and 33b are gripped as shown in FIG. After being extracted from the positioning hole 31b1, the sheet holding member 33 (separation slope 32) is moved away from the paper feed roller 7 while holding the first and second knobs 33a and 33b, and is positioned as shown in FIG. The hook 33c is locked in the second positioning hole 31b2.

Here, the positioning hook 33c is
Is locked in the second positioning hole 31b2, the sheet holding member 33 is moved to a position where the separation slope 32 is separated from the sheet feeding roller 7, whereby the contact point between the sheet feeding roller 7 and the sheet S and the top end of the top sheet 15 is longer than Z1 at the time of setting for feeding a thin sheet shown in FIG. Thereby, a thick sheet can be reliably separated.

As described above, by moving the sheet holding member 33 in accordance with the thickness of the sheet, it is possible to largely switch the feeding condition of the thin sheet and the feeding condition of the thick sheet. Various types of sheets can be handled.

When the positioning hook 33c is locked in the second positioning hole 31b2 as described above, the lower surface guide member 37 rotates to a position where it comes into contact with the first knob 33a, so that a smoother sheet feeding is achieved. Can be sent.

In this embodiment, the sheet holding member 3
Although the case where 3 is switched to two positions has been described, if the positions are switched to three or more positions, the sheet can be separated with higher accuracy. Further, in the case where the angle of the separation slope 32 with respect to the sheet stacking surface changes or the angle of the sheet bundle stacking surface with respect to the horizontal direction changes in conjunction with the switching of the sheet holding member 33, the present embodiment is specific to this embodiment. It is obvious that the effect is further enhanced.

Next, a sixth embodiment of the present invention will be described.

FIG. 18 is an enlarged view of a main part of the sheet feeding apparatus according to the present embodiment. In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts.

In FIG. 18, reference numeral 41 denotes a paper feed tray detachable from an image forming apparatus (not shown), and reference numeral 42 denotes a flexible material such as a stainless steel strip for spring or a phosphor bronze plate for spring. And a holding portion 41a for fixing the separation slope 42.

Here, in the present embodiment, when a sheet having rigidity such as thin paper is fed, the separating slope 42 is hardly bent as shown in FIG. On the other hand, when a sheet having high rigidity such as thick paper is fed, the separation slope 42 is bent as shown in FIG.

When the separation slope 42 is bent as described above, the angle between the separation slope 42 and the sheet is smaller than the initial set value (Y ° −ΔY °). This makes it easier to feed the sheet, and it is possible to feed thick paper. With the above configuration, it is possible to make the thick paper feeding performance and the thin paper double feeding prevention performance coexist using components that are simpler and have less variation.

Note that the present invention is not limited to the above embodiments, and various combinations of the embodiments are possible. For example, the feature of the sixth embodiment is the It may be applied to the first to fifth embodiments,
The configuration that is the feature of the fifth embodiment may be applied to the first embodiment.

[0133]

As described above, according to the present invention, there is provided a sheet feeding apparatus capable of reliably preventing double feeding of thin sheets and reliably feeding thick sheets. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a sheet feeding device according to a first embodiment of the present invention.

FIG. 2 is a view taken in the direction of arrow V1 in FIG. 1;

FIG. 3 is an enlarged view of a main part showing a state when a thin sheet is fed by the sheet feeding apparatus shown in FIG. 1;

FIG. 4 is an enlarged view of a main part of the sheet feeding apparatus shown in FIG. 1 when feeding a thick sheet.

FIG. 5 is a diagram illustrating a configuration of a sheet feeding device according to a second embodiment of the present invention.

FIG. 6 is an enlarged view of a main part of the sheet feeding apparatus shown in FIG. 5 when a thick sheet is fed.

FIG. 7 is an enlarged view of a main part of the sheet feeding apparatus shown in FIG. 5 when feeding a thick sheet.

FIG. 8 is a diagram illustrating a configuration of a sheet feeding device according to a third embodiment of the present invention.

FIG. 9 is a diagram illustrating a state in which a sheet is fed by the sheet feeding apparatus illustrated in FIG. 8;

FIG. 10 is a perspective view showing a main part of the sheet feeding apparatus shown in FIG. 8;

FIG. 11 is an enlarged view of a main part of the sheet feeding device shown in FIG.

FIG. 12 is a longitudinal sectional view of a sheet feeding device according to a fourth embodiment of the present invention.

FIG. 13 is a diagram showing the sheet feeding apparatus shown in FIG. 12 when a front door unit is opened.

FIG. 14 is a simplified explanatory view of a sheet lifter driving mechanism of the sheet feeding apparatus shown in FIG.

FIG. 15 is a diagram showing a configuration of a sheet feeding device according to a fifth embodiment of the present invention.

16 is a diagram illustrating a setting switching operation of the sheet feeding apparatus illustrated in FIG.

FIG. 17 is a diagram illustrating a setting state of the sheet feeding apparatus illustrated in FIG. 15 when feeding a thick sheet.

FIG. 18 is a diagram illustrating a large-capacity sheet feeding apparatus according to a sixth embodiment of the present invention.

FIG. 19 is an enlarged view of a main part of the sheet feeding device shown in FIG. 18 when a thick sheet is fed.

FIG. 20 is a diagram illustrating a schematic configuration of an image forming apparatus including a conventional sheet feeding device.

FIG. 21 is a diagram illustrating a sheet separating operation of the conventional sheet feeding apparatus.

[Explanation of symbols]

 1A Sheet feeding device B Optional feeder C Large capacity sheet feeding device D Large capacity tray mechanism main body E Front door unit 1, 30, 31, 41 Paper feed tray 2, 20, 32, 42, 53, 85 Separation slope 3, 21, 54, 86 Slope holding member 4 Sliding roller 5 Slope reference surface 6 Slope spring 7 Feed roller 24 Latch arm 33 Sheet holding member 33a, 33b Knob 37 Subordinate lower guide 56, 57 Sliding surface 61 Support slope 76 Sea lifter 100 Image forming apparatus 100B Image forming section 100C Device main body S sheet

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B65H 3/24 B65H 3/24 D 5/36 5/36 (72) Inventor Yama ▲ saki ▼ Yoshiyuki Shimomaruko, Ota-ku, Tokyo 3-30-2 Canon Inc. (72) Inventor Ryuichi Kojima 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term (reference) 3-30-2 Canon Inc. 3F101 FB01 FE03 FE17 LA02 LA05 LA07 LB03 LB05 LB06 3F343 FA02 FA05 FA06 FB02 FB03 FB04 FC01 GA01 GB01 GC01 GD01 HA01 HA16 HA17 HA31 HD09 HD11 HD17 HD20 HE07 HE08 JC09 JD02 JD09 JD15 KB03 KB05 KB06 LA02 LA03 LA12 LA14 LB02 LC07 LD10 LD28 MA10 MB08 MB18

Claims (24)

[Claims] 1. A sheet feeding means for feeding a sheet abutted on a sheet stored in a sheet storing means, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. The sheet feeding device according to claim 1, wherein the separation slope is relatively movable with respect to the sheet feeding unit. 2. A sheet feeding means for abutting a sheet stored in a sheet storing means to feed a sheet, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. The sheet feeding device according to claim 1, wherein the separation slope is configured to be movable in a sheet advancing direction along with the sheet fed from the sheet feeding unit. 3. The separation slope is provided so as to be able to advance and retreat in the sheet advancing direction in a plane including a sheet contact surface with which the leading end of the sheet abuts on the separation slope. 3. The sheet feeding device according to 1. 4. The separation slope is provided at a sheet feeding side end of a sheet storage portion of the sheet storage means, and the separation slope can be moved to a fixed slope reference plane parallel to the sheet contact surface. The sheet feeding device according to claim 3, wherein the sheet feeding device is attached. 5. When the separation slope moves along the traveling direction of the sheet along with the movement of the fed sheet, the separation slope contacts the sheet of the separation slope in an initial state. The sheet contacting surface is moved from a plane including the surface so as to be gradually separated in a direction parallel to the plane and in a direction opposite to an arrangement side of the sheet feeding means. Sheet feeding device. 6. The sheet feeding device according to claim 6, wherein the separating slope is provided at a sheet feeding side end of a sheet storing portion of the sheet storing means, and the sheet feeding is performed from a plane including the sheet contact surface in a sheet advancing direction. A slope reference surface that is inclined in a direction away from the feeding means, and the separation slope is provided on a slope holding member movable along the slope reference surface, and the sheet contact surface is separated from the separation slope by the slope holding member. 6. The sheet feeding apparatus according to claim 5, wherein the sheet feeding apparatus is moved so as to be gradually separated from the plane in a direction opposite to a side where the sheet feeding means is disposed, in a state parallel to the plane including the sheet feeding means. 7. The slope reference surface is composed of two parallel and stepped surfaces, and a slope holding member that holds the separation slope slides on both of the two slope reference surfaces. The sheet feeding device according to claim 6, wherein 8. The separation slope is configured to start moving from an initial position together with the sheet when a predetermined force is applied by a sheet fed from the sheet feeding means. The sheet feeding device according to any one of claims 1 to 7. 9. The sheet feeding apparatus according to claim 8, wherein when the separation slope moves by a force from a sheet, the separation slope returns to an initial position by its own weight. 10. The sheet feeding device according to claim 8, further comprising an elastic member for returning the separation slope to an initial position at the start of the movement. 11. A plurality of separation slopes are arranged in the width direction of a sheet, and between the plurality of separation slopes, at an initial position at the time of starting movement, the separation slope is provided on the sheet contact surface of the separation slope. The sheet feeding device according to any one of claims 5 to 10, further comprising a fixed slope member that is fixed substantially parallel to the sheet contact surface and recessed from the sheet contact surface. 12. The sheet feeding device according to claim 11, wherein a resistance force applied to a leading end of the sheet separated from the surface of the fixed slope member is smaller than a resistance force applied from the separation slope. 13. The fixed slope member is arranged such that, when the separation slope moves with the sheet from an initial state, the separation slope gradually protrudes from the sheet contact surface of the separation slope. The sheet feeding device according to claim 11. 14. The sheet feeding apparatus according to claim 1, further comprising a regulating unit that holds the separation slope moved to a predetermined position together with the sheet. 15. The apparatus according to claim 1, wherein said sheet storage means is detachably stored in the apparatus main body, and the holding operation of said restricting means is released in conjunction with a take-out operation of said sheet storage means. 15. The sheet feeding device according to 14. 16. The sheet feeding apparatus according to claim 1, wherein said sheet storage means uses a lifter-type middle plate which can move up and down while maintaining the same posture angle. Feeder. 17. A sheet feeding apparatus according to claim 16, wherein said separation slope and means for movably supporting said separation slope are provided on a front door unit which opens and closes when replenishing paper. 18. The sheet feeding device according to claim 16, wherein the lifter-type intermediate plate is inclined such that the side on which the separation slope is disposed is positioned vertically upward. 19. A sheet feeding means for abutting a sheet stored in a sheet storing means to feed a sheet, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. The sheet feeding device according to claim 1, wherein the separation slope is configured so that a sheet fed by the sheet feeding unit abuts and bends. 20. The sheet feeding apparatus according to claim 19, wherein said separation slope is formed of a flexible plate-like member. 21. A sheet feeding means for feeding a sheet in contact with a sheet stored in a sheet storing means, and a separation slope for separating and feeding the sheets fed by the sheet feeding means one by one. The sheet feeding device according to claim 1, wherein the separation slope can be moved by a manual operation in a state parallel to a direction of approaching or separating from the sheet feeding means. 22. A sheet holding member for holding a sheet in the sheet storing means is connected to the separation slope.
22. The sheet feeding apparatus according to claim 21, wherein the sheet holding member is provided so as to be movable with the movement of the separation slope. 23. A guide member which is disposed downstream of the separation slope and transfers a sheet sent out by the sheet feeding means from the separation slope to a conveyance path, and moves the guide member on the separation slope. 23. The sheet feeding apparatus according to claim 21, wherein the sheet feeding apparatus is moved in conjunction with the sheet feeding. 24. An image forming apparatus comprising: an image forming unit; and a sheet feeding device for feeding a sheet to the image forming unit, wherein the sheet feeding device is any one of claims 1 to 23. An image forming apparatus according to claim 1.