JP2000159355A - Sheet feeder and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount a sheet bundle from directly above a sheet mount section while maintaining sheet separation performance by providing the sheet mount section having an inclined surface, a sheet separation surface erected nearly vertically relative to the horizontal plane for separating a sheet in contact with the tip of the sheet, and a rear end regulating member. SOLUTION: A sheet separation surface 3 for separating a sheet S bundle in contact with the tip of the sheet S bundle mounted on the sheet mount section 20 of a sheet cassette 1 and a rear end regulating member 21 regulating the rear end position of the sheet S bundle in contact with the rear end of the sheet S bundle mounted on the sheet mount section 20 have wall faces erected nearly vertically relative to the horizontal plane. The sheet mount section 20 is connected to a sheet feed direction rear half section 20b having the nearly horizontal plane. Since the angle θ between a sheet feed direction front half section 20a and the sheet separation surface 3 is maintained, the sheet separation surface 3 and the rear end regulating member 21 are erected in the nearly vertical direction relative to the horizontal plane when supplying sheets S while maintaining sheet separation performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, etc., for separating and feeding sheets one by one from a sheet bundle stacked on a sheet placing means into an image forming apparatus main body. The present invention relates to a sheet feeding device.

[0002]

2. Description of the Related Art As shown in FIGS. 6 and 7, in a conventional image forming apparatus, sheets S are separated one by one from a sheet bundle stacked and accommodated in a sheet cassette 101, and the main body of the image forming apparatus is separated. The sheet S fed by rotation of a feed roller 102 pressed against the sheet surface to feed the sheet into the inside is pushed against a sheet separating surface 103 having a predetermined angle with respect to the sheet feeding direction. There is a type in which the sheet S is separated and fed by applying a resistance in a direction opposite to the sheet feeding direction to the leading end of the sheet S by applying the sheet S.

In order for a sheet feeding apparatus using such a separating means to exhibit a stable feeding performance, the leading end of a sheet S bundle loaded in a sheet cassette 101 must have a sheet separating surface 10.
3, the rear end regulating member 104 that regulates the rear end of the bundle of sheets S is generally disposed obliquely in parallel with the sheet separation surface 103.

[0004]

However, in the above-mentioned conventional example, the rear end regulating member 104 is disposed at an acute angle with respect to the sheet mounting surface of the sheet cassette 101, and covers the sheet S bundle toward the upper portion. Seat cassette 101
When the sheet S is replenished, the sheet S needs to be set so that the rear end of the sheet S is sunk into the acute angle side of the rear end regulating member 104.

[0005] The present invention is to solve the above-mentioned problems,
The purpose of this is that even in a sheet feeding apparatus that separates and feeds the sheet by abutting the leading end of the sheet against the sheet separating surface, it is necessary to make the rear end of the sheet fall into the acute angle side of the rear end regulating member when replenishing the sheet. It is an object of the present invention to provide a sheet feeding apparatus which can be easily set from directly above without a sheet, and an image forming apparatus provided with the sheet feeding apparatus.

[0006]

A sheet feeding apparatus according to the present invention for achieving the above object has a sheet mounting means for mounting a sheet, and a sheet feeding means disposed above the sheet mounting means. And a sheet feeding device for separating and feeding the sheet by abutting the leading end of the sheet fed by the sheet feeding device against a sheet separation surface. The latter half of the sending direction is almost horizontal,
And, a sheet mounting portion having an inclined surface in which the first half of the sheet feeding direction is inclined upward in the sheet advancing direction with respect to a horizontal plane,
A sheet placed on the sheet placement unit is fed by the sheet feeding means, and a sheet separation surface rising substantially vertically with respect to a horizontal plane for separating the sheet by contacting the leading end of the sheet, And a rear end regulating member that abuts on the rear end of the sheet placed on the sheet placing portion and rises substantially vertically with respect to a horizontal plane that regulates the rear end position of the sheet.

According to the above construction, the sheet separating surface and the rear end regulating member rise substantially vertically with respect to the horizontal plane while maintaining the inclination angle between the sheet separating surface and the first half of the sheet placing section in the sheet feeding direction. Therefore, even in a sheet feeding device that separates and feeds the sheet by abutting the leading end of the sheet against the sheet separating surface, the sheet can be easily set from directly above the sheet placing means when replenishing the sheet.

Further, another configuration of the sheet feeding apparatus according to the present invention includes a sheet cassette detachable from the image forming apparatus main body, and sheet feeding means disposed above the sheet cassette. In a sheet feeding apparatus that separates and feeds a sheet by abutting a leading end of a sheet fed by a sheet feeding unit on a sheet separating surface, the sheet cassette has a substantially horizontal surface in a rear half in a sheet feeding direction, and A sheet placement unit having a slope in which the first half in the sheet feeding direction is inclined upward in the sheet advancing direction with respect to a horizontal plane, and a sheet placed on the sheet placement unit is fed by the sheet feeding unit. A sheet separation surface that rises substantially vertically with respect to a horizontal plane for separating the sheet by abutting the leading end of the sheet, and abutting the rear end of the sheet placed on the sheet placing portion to form the sheet. rear Position and having a rear end regulating member has risen substantially in the vertical to the horizontal plane for regulating the.

According to the above construction, the sheet separating surface and the rear end regulating member rise substantially vertically with respect to the horizontal plane while maintaining the inclination angle between the sheet separating surface and the first half of the sheet placing section in the sheet feeding direction. Therefore, even in a sheet feeding apparatus that separates and feeds the sheet by abutting the leading end of the sheet against the sheet separating surface, the sheet can be easily set from directly above the sheet cassette when replenishing the sheet.

Another configuration of the sheet feeding apparatus according to the present invention includes a sheet cassette detachable from the main body of the image forming apparatus, and sheet feeding means disposed above the sheet cassette. In a sheet feeding apparatus that separates and feeds a sheet by abutting a leading end of a sheet fed by a sheet feeding unit to a sheet separating surface, the sheet cassette includes a second half in a sheet feeding direction that forms a substantially horizontal surface. A sheet mounting portion having a horizontal position forming the same plane as a substantially horizontal surface and a first half portion in a sheet feeding direction movable to an inclined position inclined upward in the sheet advancing direction with respect to the horizontal surface; The sheet placed on the sheet is fed by the sheet feeding means, and the leading end of the sheet comes into contact with the sheet and the sheet is separated from the sheet. A rear end regulating member that abuts on the rear end of the sheet placed on the placing portion and rises substantially vertically with respect to a horizontal plane that regulates the rear end position of the sheet, and the sheet of the sheet placing portion has The first half of the sheet feeding direction is at a horizontal position when the sheet cassette is taken out of the image forming apparatus main body, and transitions to an inclined position when the sheet cassette is mounted on the image forming apparatus main body.

According to the above construction, the sheet separation surface and the rear end regulating member rise substantially vertically with respect to the horizontal plane while maintaining the inclination angle between the sheet separation surface and the first half of the sheet placement section in the sheet feeding direction. In addition, when the sheet cassette is taken out of the image forming apparatus main body at the time of replenishment of the sheet, the first half of the sheet placing portion in the sheet feeding direction becomes a horizontal position,
Even with a sheet feeding device that separates and feeds the sheet by abutting the leading edge of the sheet against the sheet separation surface, the work of simply placing the sheet bundle on the sheet stacking unit from directly above the sheet cassette in a horizontal state when replenishing sheets Can be set easily.

Another configuration of the sheet feeding apparatus according to the present invention includes a sheet cassette detachable from the image forming apparatus main body, and sheet feeding means disposed above the sheet cassette. In a sheet feeding apparatus that separates and feeds sheets by abutting a leading end of a sheet fed by a sheet feeding unit on a sheet separating surface, the sheet cassette forms a substantially horizontal surface, and is capable of moving up and down. The latter half of the sheet feeding direction is interlocked with the latter half of the sheet feeding direction. When the latter half of the sheet feeding direction is at the rising position, the latter half of the sheet feeding direction becomes the horizontal position forming the same plane as the substantially horizontal plane. When the lower position is, the sheet mounting portion having a sheet feeding direction first half that transitions to an inclined position inclined upward in the sheet advancing direction with respect to the horizontal plane, and the sheet mounted on the sheet mounting portion is Sheet supply A sheet separation surface which is fed by means and rises substantially vertically with respect to a horizontal plane for separating the sheet by contacting the leading end of the sheet and the rear end of the sheet placed on the sheet placing portion. A rear end regulating member that rises substantially vertically with respect to a horizontal plane that regulates the rear end position of the sheet by contacting the sheet cassette when the sheet cassette is taken out of the image forming apparatus main body. The latter half of the sheet feeding direction is at the rising position, and the first half of the sheet feeding direction is at the horizontal position, and when the sheet cassette is mounted on the image forming apparatus main body, the latter half of the sheet feeding direction is at the lowered position, and The first half of the sheet feeding direction is shifted to the inclined position.

According to the above construction, the sheet separating surface and the rear end regulating member rise substantially vertically with respect to the horizontal plane while maintaining the inclination angle between the sheet separating surface and the first half of the sheet placing portion in the sheet feeding direction. In addition, when the sheet cassette is taken out of the image forming apparatus main body, when the sheet is supplied, the second half of the sheet placing portion in the sheet feeding direction is at the raised position, and the first half of the sheet feeding direction is at the horizontal position. Even with a sheet feeding device that separates and feeds the sheet by abutting the leading edge of the sheet against the separation surface, it only needs to place the sheet bundle on the sheet placement section from above the sheet cassette in a horizontal state when replenishing sheets. The tray can be set easily, and particularly, since the sheet placing portion is lifted above the sheet cassette to make the tray shallow, the sheet supply operation is easy.

Another configuration of the sheet feeding apparatus according to the present invention includes a sheet cassette detachable from the image forming apparatus main body, and sheet feeding means disposed above the sheet cassette. In a sheet feeding apparatus that separates and feeds a sheet by abutting a leading end of a sheet fed by a sheet feeding unit against a sheet separating surface, the sheet cassette includes a sheet mounting unit that forms a substantially horizontal surface, The sheet placed on the sheet placing portion is fed by the sheet feeding means, and the sheet is inclined upward in the sheet advancing direction with respect to the vertical direction of the horizontal plane for separating the sheet by contacting the leading end of the sheet. A separating surface, a position rising substantially vertically with respect to a horizontal plane that abuts on a rear end of the sheet placed on the sheet placing portion and regulates a rear end position of the sheet, and a tilt parallel to the sheet separating surface. And a movable trailing edge regulating member to a position, the trailing edge regulating member becomes substantially vertical position when the sheet cassette is removed from the image forming apparatus main body,
When the sheet cassette is mounted on the image forming apparatus main body, the sheet cassette shifts to an inclined position parallel to the sheet separation surface.

According to the above configuration, the rear end regulating member can be moved to a position where the rear end regulating member rises substantially vertically with respect to the horizontal plane and an inclined position parallel to the sheet separating surface, and the sheet cassette is taken out from the image forming apparatus main body. When the sheet is replenished, the rear end regulating member is at a substantially vertical position, so that even in a sheet feeding apparatus that separates and feeds the sheet by abutting the leading end of the sheet on the sheet separating surface, the rear end of the sheet is rearwardly fed when the sheet is replenished. This is preferable because it does not need to be sunk into the acute angle side of the end regulating member, can be easily set from directly above the sheet cassette, and has a simple configuration without using any extra space.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sheet feeding apparatus according to the present invention and an image forming apparatus including the sheet feeding apparatus, which is applied to a laser beam printer. FIG. 1 is an explanatory cross-sectional view illustrating a configuration of an image forming apparatus including a sheet feeding apparatus according to the present invention, and FIG. 2 is an explanatory cross-sectional view illustrating a configuration of a first embodiment of the sheet feeding apparatus according to the present invention. .

In FIG. 1, a plurality of sheets S made of paper, synthetic resin, or the like are provided in a sheet cassette 1 which is disposed below the image forming apparatus and serves as a sheet mounting means detachable from the image forming apparatus main body. The sheet S fed out by the feed roller 2 which is a sheet feeding unit which rotates in the clockwise direction in FIG. 1 when the sheet S is fed and has a leading end The image forming apparatus collides with the sheet separating surface 3 having an angle of θ with respect to the feeding direction (sheet advancing direction) and receives resistance in a direction opposite to the feeding direction, whereby the leading end of the sheet S bundle is separated and separated. It is sent out one by one into the main body.

The feed roller 2 is rotatably held at the tip end of an arm member 4 swinging about a rotation shaft 4a.
It is configured to land at a position corresponding to the stacking amount of the sheets S.

Sheet S sent out by feed roller 2
Is transferred by a pair of conveying rollers 5 and 6 to a toner image transfer section between an electrophotographic photosensitive drum 7 serving as an image forming means and a transfer roller 8.

On the other hand, the photosensitive drum 7 is rotating in the counterclockwise direction in FIG. 1 and is uniformly charged by the charger 9 and then selectively emitted from the laser scanner 10 based on an image signal. Exposure is performed by a laser beam to form an electrostatic latent image.

The electrostatic latent image is developed into a toner image by a developing unit 11, and the toner image formed on the photosensitive drum 7 is electrically attracted by a transfer roller 8 to pass through a toner image transfer unit. The image is formed by being sequentially transferred to the printing surface (upper surface) of the sheet S to be printed.

The sheet S on which the toner image has been formed is guided to a nip portion between the heating means 13 of the fixing device 12 and the pressing roller 14 pressed against the same, and the sheet S passes through the nip portion while passing through the nip portion. The toner image transferred to the printing surface is heated and pressed to be fixed on the printing surface of the sheet S.

The sheet S having passed through the fixing device 12 is guided to a pair of face-up discharge rollers 17 by a sheet guide member 15 and a separation guide 16, and further sent to a pair of face-down discharge rollers 18 to be fed to the face-down discharge roller 18. It is discharged onto the discharge tray 19 by the pair 18.

Next, the configuration of the first embodiment of the sheet feeding apparatus according to the present invention will be described in detail with reference to FIG. In FIG. 2, the leading end of the sheet bundle stacked on the sheet stacking unit 20 of the sheet cassette 1 abuts on the sheet separating surface 3 for separating the sheet S stack and the sheet stacking unit 20. The rear end regulating member 21 that abuts on the rear end of the bundle of sheets S and regulates the rear end position of the bundle of sheets S has a wall surface that rises substantially vertically with respect to a horizontal plane.

The sheet mounting section 20 has a substantially horizontal plane rear half section 20b and a sheet rear half section 20b.
20b, while satisfying the condition that the sheet separation surface 3 is a wall rising substantially perpendicular to the horizontal plane while maintaining an angle θ with the sheet separation surface 3 suitable for separating the sheet S. And a front part 20a in the sheet feeding direction having an inclined surface inclined by an angle α (α = 90 ° −θ) above the horizontal plane in the sheet advancing direction.

When the sheet cassette 1 is taken out from the main body of the image forming apparatus and the sheets S are replenished while maintaining the sheet separating performance by maintaining the angle θ between the first half 20a of the sheet feeding direction and the sheet separating surface 3. The sheet S can be inserted from directly above the sheet cassette 1 by the sheet separating surface 3 and the rear end regulating member 21 rising in a substantially vertical direction with respect to a horizontal plane, so that the sheet S can be easily set. I can do it.

Next, a second embodiment of the sheet feeding apparatus according to the present invention will be described with reference to FIG. FIG. 3A is an explanatory sectional view showing a state in which the sheet cassette is taken out of the image forming apparatus main body in the second embodiment of the sheet feeding apparatus according to the present invention, and FIG. 3B is a sheet cassette in the second embodiment. FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, similarly to the first embodiment, the sheet separating surface 3 and the rear end regulating member 21 have wall surfaces rising substantially vertically with respect to a horizontal plane. The rear half part 20b in the direction forms a substantially horizontal plane.

Further, the first half 20a of the sheet feeding direction connected to the second half 20b of the sheet feeding direction is maintained at an angle θ with the sheet separating surface 3 suitable for separating the sheet S while maintaining the angle θ. Position (see FIG. 3 (b)) and the second half 20b of the sheet feeding direction in which the angle .alpha.
And a horizontal position forming the same plane (see FIG. 3A).

The first half 20a in the sheet feeding direction is provided rotatably about a rotation shaft 20c provided at the leading end in the sheet advancing direction of the second half 20b in the sheet feeding direction.
As shown in FIG.
Is taken out, the first half 20a in the sheet feeding direction is lowered to the horizontal position by its own weight.

As shown in FIG. 3B, when the sheet cassette 1 is mounted on the main body of the image forming apparatus, a lifter rotatably held around a rotation shaft 22a provided on the main body of the sheet cassette 1 is provided. The input portion 22b of the sheet cassette 22 protruding from the side surface of the sheet cassette 1 is engaged with a projection 23 provided on the image forming apparatus main body side, and the lifter 22 is rotated.
The output portion 22c of the sheet feeder abuts on the lower surface of the leading end of the front half 20a in the sheet feeding direction to rotate the front half 20a in the sheet feeding direction to the rotating shaft 20c.
Is pushed up to the inclined position shown in FIG.

When the sheet cassette 1 is mounted on the main body of the image forming apparatus, the angle .theta. Between the first half 20a in the sheet feeding direction and the sheet separating surface 3 is maintained, so that the image forming apparatus can maintain the sheet separating performance. When taking out the sheet cassette 1 from the main body and replenishing the sheet S, the sheet S is inserted from directly above the sheet cassette 1 because the sheet separating surface 3 and the rear end regulating member 21 stand up in a substantially vertical direction with respect to a horizontal plane. The sheet stacking unit 20 can be set in a horizontal state by setting the sheet placement unit 20 to be substantially horizontal, and the setting of the sheet S can be facilitated.

Other configurations are the same as those of the first embodiment, and the same effects can be obtained.

Next, a third embodiment of the sheet feeding apparatus according to the present invention will be described with reference to FIG. FIG. 4A is an explanatory cross-sectional view showing a state in which a sheet cassette is taken out of an image forming apparatus main body in a third embodiment of the sheet feeding apparatus according to the present invention, and FIG. 4B is a sheet cassette in the third embodiment. FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body. In addition, components configured in the same manner as the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

In the present embodiment, the sheet separating surface 3 and the rear end regulating member 21 have wall surfaces rising substantially perpendicular to the horizontal plane, as in the previous embodiment. In the first half 20a of the sheet feeding direction, the leading end in the sheet advancing direction is rotatable around a rotation shaft 20d provided in the main body of the sheet cassette 1, and further, the second half of the sheet feeding direction.
It is connected rotatably around a rotation shaft 20e provided at the leading end of the sheet 20b in the sheet advancing direction.

The second half 20b in the sheet feeding direction is rotatably provided on both sides of the second half 20b in the sheet feeding direction about rotation shafts 31a and 32a provided in the main body of the sheet cassette 1. The pair of cams 31 and 32 are provided with flange portions 20f provided on both sides in the sheet feeding direction of the rear half portion 20b in the sheet feeding direction.
, So as to move up and down in a substantially horizontal state.

The cams 31 and 32 are connected by a connecting member 33 so as to be interlocked with each other. A protrusion 32b provided on the cam 32 disposed at the rear end of the sheet cassette 1 in the sheet advancing direction is provided. The cam 32 rises along the guide portion 34 while being guided by the guide portion 34 provided in the image forming apparatus main body, and the cam 31 rises in conjunction with the connection member 33.

Then, a pair of cams 31 and 32 are brought into contact with the flanges 20f on both sides of the rear half portion 20b in the sheet feeding direction, so that the rear half portion 20b of the sheet feeding direction is horizontal as shown in FIG. The first half 20a of the sheet feeding direction, which rises in the state and interlocks with the second half 20b of the sheet feeding direction via the rotating shaft 20e, rotates about the rotating shaft 20d to form a horizontal plane. Move to position.

That is, when the second half 20b in the sheet feeding direction is at the lowered position, the first half 20a in the sheet feeding direction of the sheet placing section 20 has an angle θ with the sheet separation surface 3 suitable for separating the sheet S. The angle α (α = 9) that satisfies the condition that the sheet separation surface 3 is formed in a direction substantially perpendicular to the horizontal plane while maintaining
0 [deg.]-[Theta]) (see FIG. 4 (b)), and when the latter half 20b of the sheet feeding direction is at the rising position, the first half 20a of the sheet feeding direction is shifted to the latter half 20b of the sheet feeding direction.
And a horizontal position (see FIG. 4 (a)) forming the same plane as that of FIG.

As shown in FIG. 4A, when the sheet cassette 1 is taken out of the image forming apparatus main body, the guide portion 34 provided on the image forming apparatus main body lifts the projection 32b of the cam 32 as described above. The cam 32 is raised to the raised position, and the cam 31 connected by the connecting member 33 is also raised to the raised position.

The cams 31, 32 are in contact with the flanges 20f of the rear half 20b of the sheet feeding direction, whereby the rear half 20b of the sheet feeding direction is pushed up to the raised position and the front half of the sheet feeding direction. 20a is the horizontal position.

On the other hand, as shown in FIG. 4B, when the sheet cassette 1 is mounted on the image forming apparatus main body, the guide portion 34
Pushes down the projection 32b of the cam 32, the cam 32 is pushed down to the lowered position, and the cam 31 connected by the connecting member 33 is also pushed down to the lowered position, so that the rear half 20b in the sheet feeding direction is pushed down to the lowered position. At the same time, the first half 20a in the sheet feeding direction shifts to the inclined position.

When the sheet cassette 1 is mounted on the main body of the image forming apparatus, the angle .theta. Between the first half 20a in the sheet feeding direction and the sheet separating surface 3 is maintained, so that the image forming operation can be performed while maintaining the sheet separating performance. Sheet cassette 1 from the main unit
When the sheet is taken out and replenished with the sheet S, the sheet S can be inserted from directly above the sheet cassette 1 because the sheet separation surface 3 and the rear end regulating member 21 stand up substantially in the vertical direction. The sheet S can be set on a shallow tray by raising the number 20, and the work of setting the sheet S can be facilitated.

Other configurations are the same as those of the above embodiments, and the same effects can be obtained.

Next, a fourth embodiment of the sheet feeding apparatus according to the present invention will be described with reference to FIG. FIG. 5A is a cross-sectional explanatory view showing a state in which a sheet cassette is taken out of an image forming apparatus main body in a fourth embodiment of the sheet feeding apparatus according to the present invention, and FIG. 5B is a sheet cassette in the fourth embodiment. FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body. In addition, components configured in the same manner as the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

In the present embodiment, the sheet placing portion 20 forms a substantially horizontal surface, and the sheet separating surface 3 separates the sheet S fed by the feeding roller 2 by receiving a resistance in a direction opposite to the feeding direction. In this case, an inclined wall surface is formed at an angle θ with respect to the sheet placement unit 20 which is appropriate for the operation.

Further, the rear end regulating member 21 is a sheet cassette 1
The rotation shaft 21 is rotatable about a rotation shaft 21a provided on the main body and is rotated by a torsion coil spring 41 fitted on the rotation shaft 21a.
5A is always urged clockwise in FIG. 5A. When the sheet cassette 1 is taken out of the image forming apparatus main body, the rear surface of the rear end regulating member 21 abuts on the stopper 42. In addition, as shown in FIG. 5 (a), it is held at a position that stands substantially vertically with respect to the horizontal plane.

On the other hand, a roller 43 is provided at the upper end of the rear end regulating member 21 so as to be rotatable with respect to the rear end regulating member 21. A guide member 44 is provided at the height position.

When the sheet cassette 1 is mounted on the main body of the image forming apparatus, as shown in FIG. 5B, a roller 43 serving as an input unit provided at the upper end of the rear end regulating member 21 has a guide member 44. When the rear end regulating member 21 is in contact with the lower surface and the rear end regulating member 21 resists the elastic force of the torsion coil spring 41, the rear end regulating member 21 is rotated about the rotation shaft 21a as shown in FIG.
It is rotated in the counterclockwise direction of (b), and is held at an inclined position parallel to the sheet separation surface 3.

Thus, the rear end regulating member 21 is configured to be movable between an upright position where the rear end regulating member rises in a substantially vertical direction and an inclined position parallel to the sheet separating surface 3.

That is, when the sheet cassette 1 is taken out of the image forming apparatus main body, the rear end regulating member 21 is urged by the torsion coil spring 41 to be in the upright position, as described above. When the is mounted on the image forming apparatus main body, the roller 43 of the rear end restricting member 21 engages with the guide member 44 provided on the image forming apparatus main body to lower the rear end restricting member 21 to the inclined position, and is stacked vertically. The sheet S is regulated so that the leading edge of the sheet S follows the sheet separation surface 3.

When the sheet cassette 1 is taken out of the main body of the image forming apparatus and the sheets S are supplied, the sheets S can be inserted from directly above the sheet cassette 1 because the rear end regulating member 21 rises substantially in the vertical direction. As described above, since the sheet stacking section 20 is always formed at a low position of the sheet cassette 1 on a substantially horizontal plane without being raised as in the above-described embodiments, no wasteful space is required, and the stacking amount of the sheets S is large. Can be secured.

Other configurations are the same as those of the above embodiments, and the same effects can be obtained.

In each of the above embodiments, an example has been shown in which the present invention is applied to the sheet cassette 1 which is attached to and detached from the image forming apparatus main body. However, the present invention can be applied to other sheet placing means such as a sheet deck. .

[0055]

Since the present invention has the above-described configuration and operation, according to the first and second aspects, the angle between the sheet separation surface and the first half of the sheet feeding direction is maintained. By arranging the sheet separation surface and the rear end regulating member in a direction substantially perpendicular to the horizontal plane, the sheet bundle can be stacked from directly above the sheet mounting means (sheet cassette) while maintaining the sheet separation performance. It is possible to set sheets easily.

According to the third aspect of the present invention,
By arranging the sheet separating surface and the rear end regulating member substantially vertically with respect to the horizontal plane while maintaining the angle between the sheet separating surface and the first half of the sheet feeding direction, the sheet bundle can be maintained while maintaining the sheet separating performance. Can be stacked from directly above the sheet cassette, and the sheet setting operation can be further facilitated by making the shape of the sheet mounting portion substantially horizontal when the sheets are set.

According to the fourth aspect of the present invention,
By arranging the sheet separating surface and the rear end regulating member substantially vertically with respect to the horizontal plane while maintaining the angle between the sheet separating surface and the first half of the sheet feeding direction, the sheet bundle can be maintained while maintaining the sheet separating performance. Can be stacked from directly above the sheet cassette, the shape of the sheet placing portion when setting the sheet is substantially horizontal, and the sheet placing portion is further raised to make the tray shallower, so that the sheet setting operation is further performed. Can be easier.

Further, according to the configuration described in claim 5,
The sheet bundle can be stacked from directly above the sheet cassette by the rear end regulating member standing upright in the vertical direction with respect to the horizontal plane when setting the sheet. A large amount can be secured.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view illustrating a configuration of an image forming apparatus including a sheet feeding device according to the present invention.

FIG. 2 is an explanatory cross-sectional view illustrating a configuration of a first embodiment of a sheet feeding apparatus according to the present invention.

FIG. 3A is a cross-sectional view illustrating a state in which a sheet cassette is removed from an image forming apparatus main body in a second embodiment of the sheet feeding apparatus according to the invention, and FIG. 3B is a sheet cassette in the second embodiment; FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body.

FIG. 4A is a cross-sectional explanatory view illustrating a state in which a sheet cassette is removed from an image forming apparatus main body in a third embodiment of the sheet feeding apparatus according to the present invention, and FIG. 4B is a sheet cassette in the third embodiment; FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body.

FIG. 5A is a cross-sectional view illustrating a state in which a sheet cassette is removed from a main body of an image forming apparatus according to a fourth embodiment of the sheet feeding apparatus according to the present invention, and FIG. 5B is a sheet cassette according to the fourth embodiment; FIG. 3 is an explanatory cross-sectional view showing a state in which is mounted on the image forming apparatus main body.

FIG. 6 is a diagram illustrating a conventional example.

FIG. 7 is a diagram illustrating a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Sheet cassette, 2 ... Feeding roller, 3 ... Sheet separation surface, 4 ... Arm member, 4a ... Rotating shaft, 5, 6 ... Conveyor roller pair, 7 ... Photoconductor drum, 8 ... Transfer roller, 9 ... Charging Device, 10: laser scanner, 11: developing device, 12: fixing device,
13 ... heating means, 14 ... pressure roller, 15 ... sheet guide member, 16 ... separation guide, 17 ... face-up discharge roller pair, 18 ... face-down discharge roller pair, 19 ... discharge tray, 20 ... sheet placement section, 20a: the first half of the sheet feeding direction,
20b: Rear half of sheet feeding direction, 20c: Rotating shaft, 20d: Rotating shaft, 20e: Rotating shaft, 20f: Flange, 21: Rear end regulating member,
21a: rotating shaft, 22: lifter, 22a: rotating shaft, 22b: input unit, 22c: output unit, 23: protrusion, 31, 32 ... cam, 31
a, 32a: rotating shaft, 32b: projection, 33: connecting member, 34:
Guide part, 41 ... Torsion coil spring, 42 ... Stopper, 43 ...
Roller, 44: Guide member, S: Sheet

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F343 FA02 FB02 FB03 FB04 FC01 GA03 GB01 GC01 GD02 HA14 HB03 HD06 HD10 HD18 HE08 JD03 JD15 JD39

Claims (7)

[Claims] 1. A sheet mounting means for mounting a sheet, and a sheet feeding means disposed above the sheet mounting means, wherein a leading end of the sheet fed by the sheet feeding means is provided. In a sheet feeding apparatus that separates and feeds a sheet by abutting against a sheet separating surface, the sheet mounting unit includes a sheet feeding direction rear half part substantially in a horizontal plane, and a sheet feeding direction front half part with respect to a horizontal plane. A sheet placing portion having an inclined surface inclined upward in the sheet advancing direction, and a sheet placed on the sheet placing portion is fed by the sheet feeding means, and the leading end of the sheet comes into contact with the sheet to feed the sheet. A sheet separating surface that rises substantially vertically with respect to a horizontal plane for separation, and a horizontal plane that abuts on the rear end of the sheet placed on the sheet mounting portion and regulates the rear end position of the sheet. The rear end which stood up vertically Sheet feeding apparatus comprising: the control member. 2. A sheet cassette detachably mountable to an image forming apparatus main body, and a sheet feeding means disposed above the sheet cassette, wherein a leading end of a sheet fed by the sheet feeding means is set to a sheet. In a sheet feeding apparatus for separating and feeding sheets by abutting against a separation surface, the sheet cassette is configured such that a rear half of the sheet feeding direction is substantially horizontal, and a front half of the sheet feeding direction has a sheet advance relative to a horizontal plane. A sheet placing portion having an inclined surface inclined upward in the direction, and a sheet placed on the sheet placing portion is fed by the sheet feeding means, and a leading end of the sheet comes into contact with the sheet to separate the sheet. A sheet separation surface that rises substantially vertically with respect to the horizontal plane of the sheet, and stands substantially vertically with respect to a horizontal plane that contacts the rear end of the sheet placed on the sheet placing portion and regulates the position of the rear end of the sheet. Sheet feeding apparatus characterized by having a trailing edge regulating member wanted. 3. A sheet cassette detachably mountable to an image forming apparatus main body, and a sheet feeding means disposed above the sheet cassette, wherein a leading end of the sheet fed by the sheet feeding means is set to a sheet. In a sheet feeding device that separates and feeds sheets by abutting against a separation surface, the sheet cassette includes a rear half portion in a sheet feeding direction that forms a substantially horizontal plane, and a horizontal position and a horizontal plane that form the same plane as the substantially horizontal plane. A sheet placement section having a first half in a sheet feeding direction movable to an inclined position inclined upward in the sheet advancing direction, and a sheet placed on the sheet placement section being fed by the sheet feeding means. The sheet separation surface, which is fed up and rises substantially vertically with respect to the horizontal plane for separating the sheet by contacting the leading end of the sheet, and abutting on the rear end of the sheet placed on the sheet placing portion A rear end regulating member that rises substantially vertically with respect to a horizontal plane that regulates the rear end position of the sheet, and the first half of the sheet placing section in the sheet feeding direction is the sheet cassette removed from the image forming apparatus main body. Wherein the sheet cassette is shifted to a horizontal position when the sheet cassette is attached to the main body of the image forming apparatus. 4. A sheet cassette detachably mountable to the image forming apparatus main body, and a sheet feeding means disposed above the sheet cassette, wherein a leading end of the sheet fed by the sheet feeding means is used as a sheet. In a sheet feeding apparatus for separating and feeding sheets by abutting against a separation surface, the sheet cassette forms a substantially horizontal plane, and is capable of moving up and down in a sheet feeding direction latter half, and the sheet feeding direction latter half. When the latter half of the sheet feeding direction is at the ascending position, the horizontal position is substantially the same as the horizontal plane and the horizontal position is formed. When the latter half of the sheet feeding direction is at the lowering position, it is above the horizontal plane in the sheet advancing direction. A sheet placing portion having a sheet feeding direction front half that transitions to an inclined position that is inclined to a position where the sheet placed on the sheet placing portion is fed by the sheet feeding means, and the leading end of the sheet is Contact A sheet separating surface that rises substantially vertically with respect to a horizontal plane for separating sheets, and a horizontal surface that abuts against the rear end of the sheet placed on the sheet mounting portion and regulates the rear end position of the sheet. And a rear end regulating member that rises substantially vertically, and wherein the sheet placement portion is at a raised position in the latter half of the sheet feeding direction when the sheet cassette is removed from the image forming apparatus main body, and The first half of the sheet feeding direction is at the horizontal position, and when the sheet cassette is mounted on the image forming apparatus main body, the second half of the sheet feeding direction is at the lowered position, and the first half of the sheet feeding direction is shifted to the inclined position. A sheet feeding device, characterized in that: 5. A sheet cassette detachably mountable to the image forming apparatus main body, and a sheet feeding means disposed above the sheet cassette, wherein a leading end of the sheet fed by the sheet feeding means is set to a sheet. In a sheet feeding apparatus that separates and feeds a sheet by abutting against a separation surface, the sheet cassette includes: a sheet placement unit that forms a substantially horizontal surface; A sheet separating surface that is fed by a feeding unit, and is inclined upward in a sheet advancing direction with respect to a vertical direction of a horizontal plane for separating the sheet by abutting the leading end of the sheet, and placed on the sheet mounting portion. And a rear end regulating member movable to a position rising substantially vertically with respect to a horizontal plane which contacts the rear end of the sheet and regulates the rear end position of the sheet and an inclined position parallel to the sheet separating surface. I The trailing end regulating member is at a substantially vertical position when the sheet cassette is taken out of the image forming apparatus main body, and transitions to an inclined position parallel to the sheet separation surface when the sheet cassette is mounted on the image forming apparatus main body. A sheet feeding device. 6. The sheet feeding means includes an arm member that swings around a rotation axis, and a feeding rotary body rotatably held at a tip end side of the arm member. The sheet feeding device according to claim 1. 7. An image forming apparatus comprising: the sheet feeding device according to claim 1; and an image forming unit that forms an image on a sheet.