JP2000118730A - Sheet material loading device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust a sheet material loading position so as to stabilize sheet material conveyance by arranging an energizing force changing means changing energizing force based on an energizing member in compliance with a sheet material loading amount. SOLUTION: A cam 7 is molded integrally with a right-hand protective member 5 and supported rotationally in a shaft 5a, and a pressing contact plate 9 is lifted and energized by means of an energizing spring 16. A pressure controlling member 17 is arranged between the cam 7 and the right-hand protective member 5 while allowing the shaft 5a to slide, and at the tip of the pressure controlling member 17, two springs 18 are supported in the upper and lower positions so as to be brought into contact with the tip part of a pressing spring fixed to a right-hand regulating member 4. On the pressure controlling member 17 side of the cam 7, a gradually varied projection part 7b is arranged, and the height of the projection part 7b can be changed according to an angle of rotation of the cam 7. When the pressure controlling member 17 is pressed to the projection part 7b of the cam 7, the shaft 5a is parallelly slid onto the pressing spring side so as to press a pressing spring tip part 6b via the spring 18, and consequently, a pressure energizing a loading member 15 toward a left-hand regulating member 2 is varied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material stacking apparatus provided in an image forming apparatus for forming an image on a sheet material.

[0002]

2. Description of the Related Art FIG. 10 is an explanatory sectional view showing a schematic structure of an image forming apparatus. The image forming apparatus receives a supply of the sheet material from a sheet cassette 41 which is loaded with the sheet material and is detachable.

[0003] As shown in FIG.
Reference numeral 1 is attached to the image forming apparatus 40 by a positioning pin or the like (not shown). The image forming apparatus 41 includes the sheet cassette 4
A feeding roller 43 serving as a feeding unit comes in contact with the sheet material 15 stacked on the sheet 1 while rotating in the direction of arrow a in FIG. 10, and pushes the sheet material 15 toward the transport path 44.

Then, the uppermost sheet material of the sheet material 15 is separated by the separation pad 8 provided on the paper feed cassette 41 and fed to the transport path 44, and then transported by the transport roller pair 45.

The conveyed sheet material 15 enters the nip of the pair of registration rollers 46 so that the writing position of the image formed on the sheet material always becomes a fixed position from the front end of the sheet material, and then forms a loop. Position and posture are adjusted.

After entering the nip, the conveying roller pair 46 temporarily stops rotating, and the image data from the controller board 55 is sent to the developing cartridge 47 by the scanner 48.
At the timing of writing as an image (latent image) on the photosensitive drum 49 held at the position, rotation with the registration roller pair 46 is started.

In the cartridge 47, a photosensitive drum 49 is provided.
A toner for developing the image (latent image) formed thereon is held in a container, and the image developed in the cartridge is transferred to the sheet material 15 by the transfer roller 50.

After the transfer, the toner remaining on the photosensitive drum 49 is discharged into a waste toner container (not shown) by a cleaning mechanism (not shown) in the cartridge.

The sheet material 15 to which the image has been transferred is fixed to the fixing device 5.
1 and the image is fixed on the sheet material 15, and the image formation is completed.

Then, the sheet material on which the image is formed is conveyed on a sheet material conveyance path 44 by a pair of paper discharge rollers 52 and 53, and is discharged to a paper discharge tray 54 outside the apparatus.

In the image forming apparatus 40 having such a configuration, a sheet feeding cassette 41 serving as a sheet material stacking apparatus detachable from the image forming apparatus 40 has a configuration as shown in FIG.

In FIG. 11, the sheet material stacked on the sheet cassette is a sheet cassette provided so that the writing position of an image formed on the sheet material is always at a predetermined position from the side end surface of the sheet material. The inner reference plate 56 is urged by a pressure spring 57a fixed on a regulating plate 57 provided opposite to the reference plate.

The pressing spring 57a has a rear end portion 57b which contacts the middle portion of the sheet material and a front end portion 5 which contacts the front end portion of the sheet material.
7c, the entirety of the sheet material is urged against the reference plate 56 by the rear end 57b of the pressure spring, and the front end 57 of the pressure spring 57a is pressed.
c urges the leading end of the sheet material against the reference plate 56 to adjust the posture of the sheet material.

Inside the paper feed cassette 41, there are provided pressure contact plates 9 rotatably mounted on both side walls of the paper feed cassette 41, and sheet materials are stacked on the pressure contact plates 9.
Further, a rear end regulating plate 12 for regulating the rear end position of the stacked sheet materials is provided at the rear of the sheet cassette 41.

On the bottom surface of the sheet cassette 41 on the sheet feeding side, the sheet cassette is connected to the image forming apparatus 40 shown in FIG.
A pressure spring 10 is provided so as to come into contact with a predetermined position on the back surface of the pressure contact plate 9 that faces the feeding roller 43 provided in the image forming apparatus 40 when the pressure contact plate 9 is mounted on the pressure contact plate 9. Is urged in the direction of the feed roller.

Further, a separation pad 8 for separating the sheet material when the feeding roller 43 feeds the sheet material is provided at the tip of the sheet-feeding-side press-contact plate of the sheet cassette 41. I have.

[0017]

However, in the above conventional example, the reference plate 56 provided in the sheet cassette 41 is not provided.
The spring pressure of the pressure spring 57a of the regulating plate 57 for urging the sheet material is constant regardless of the amount of the loaded sheet material, but the weight of the loaded sheet material differs between the fully loaded state and the small loaded state. However, if the sheet material is urged securely when the sheet material is fully loaded, the sheet material may be deformed by losing the spring pressure when the load is small, and if the sheet is fed in that state, the sheet material may be skewed or jammed. is there.

Accordingly, when the spring pressure is reduced so that the sheet material is not deformed at the time of small loading, the sheet material is moved to the reference plate 56 at full loading.
The sheet material is not sufficiently pressed against the reference plate 56, and the writing position of the image formed on the sheet material is not at a predetermined position from the side end surface of the sheet material. In some cases, it is necessary to press the sheet material against the reference plate 56 when the sheet material is loaded on the sheet feeding cassette 41.

Since the required optimum spring pressure varies depending on the size of the sheet material, when the user needs to press the large-size sheet material, as in the case of the change in the load capacity, for example. was there.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to apply an appropriate urging force by an urging member according to a change in a loaded amount or a size of a sheet material. An object of the present invention is to provide a sheet material stacking apparatus and an image forming apparatus capable of stabilizing sheet material conveyance by adjusting a sheet material stacking position and stabilizing an image forming position to be performed after conveyance. .

[0021]

In order to achieve the above object, according to the present invention, there is provided a sheet material loading means for loading and lifting a sheet material, and a sheet disposed on the sheet material loading means and loaded. A reference member that positions one end in the width direction of the sheet material, a width regulating member that is disposed at the other end position in the width direction of the sheet material facing the reference member, and the sheet material stacking means. An urging member for urging the loaded sheet material toward the reference member, wherein the urging force changing means changes the urging force of the urging member in accordance with the amount of the sheet material loaded. It is characterized by having.

Sheet material loading means for loading and lifting the sheet material; a reference member disposed on the sheet material loading means for positioning one end of the loaded sheet material in the width direction; A width regulating member disposed at the other end position in the width direction of the sheet material, and an urging member for urging the sheet material stacked on the sheet material stacking means toward the reference member side. In the sheet material stacking apparatus provided, at least one of the reference member and the width regulating member is disposed so as to be movable in a width direction according to a width of the sheet material stacked on the sheet material stacking means, and It is characterized by comprising an urging force changing means for changing the urging force of the member according to the width of the sheet material.

Sheet loading means for loading and lifting the sheet material; a reference member arranged on the sheet loading means for positioning one end of the loaded sheet material in the width direction; and a sheet loading means. A width regulating member disposed at the other end position in the width direction of the sheet material stacked on the sheet member, and a biasing member supported by the width regulating member and biasing the sheet material toward the reference member. In the sheet material stacking device, at least one of the reference member and the width regulating member is disposed so as to be movable in the width direction in accordance with the width of the sheet material stacked on the sheet stacking means, and is provided with an urging member. The apparatus is characterized in that there is provided an urging force changing means for changing the force in accordance with the stacked amount of the sheet material and the width of the sheet material.

It is also preferable that the urging force changing means changes the urging force of the urging member in conjunction with the elevating operation of the sheet stacking means.

The urging means has a spring for pressing the side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to the elevation position to rotate the force of the spring. It is also preferable to provide a cam for changing

It is also preferable that the urging force changing means changes the urging force of the urging member in conjunction with the movement of the width regulating member.

The urging means has a spring which presses a side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to the moving position to rotate the force of the spring. It is also preferable to provide a cam for changing

It is also preferable that the urging force changing means changes the urging force of the urging member in conjunction with the elevating operation of the sheet stacking means and the moving operation of the width regulating member.

The urging means has a spring which presses a side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to the elevation position to rotate the force of the spring. It is also preferable to provide a cam that engages with the width regulating member and rotates according to the moving position to change the force of the spring.

The cam is rotatably supported about an axis extending in the width direction of the sheet material, and the cam is provided with a projection which can contact the spring. It is also preferable to change the force of the spring by changing.

It is also preferable that the urging force changing means continuously changes the urging force of the urging member in accordance with a position at which the sheet material stacking means moves up and down or a position at which the width regulating member moves.

[0032] It is also preferable that the urging force changing means changes the urging force of the urging member in a stepwise manner according to the elevation position of the sheet material stacking means or the moving position of the width regulating member.

[0033] The urging force changing means may be provided on the width regulating member.

It is preferable that the urging force changing means is provided on a protection member for protecting an edge of a width regulating plate attached to the width regulating member.

The image forming apparatus includes the above-described sheet material stacking apparatus, and image forming means for forming an image on the sheet material fed from the sheet material stacking apparatus.

It is also preferable that the sheet stacking device is a sheet cassette detachably mounted on the image forming apparatus main body.

[0037]

(First Embodiment) FIG. 1 shows a sheet feeding cassette 1 as a sheet material stacking apparatus to which the present invention is applied.
1 is a diagram illustrating a configuration of a first exemplary embodiment. The sheet cassette 1 is detachably mounted on the image forming apparatus having the configuration shown in FIG.

The sheet cassette 1 is a sheet cassette on which sheets such as A3 and A4 sheets having different sizes are stacked and the center of the sheet is used as a reference.

In FIG. 1, inside a cassette tray 11 constituting a framework of the paper feed cassette 1, there are provided pressure contact plates 9 which are rotatably mounted on both side walls of the cassette tray 11 and which move up and down.

Further, on the bottom surface of the cassette tray 11 on the sheet feeding side, there is a pressing member which abuts on a predetermined position on the back surface of the pressing plate 9 corresponding to the feeding roller 43 of the image forming apparatus 40 shown in FIG. A pressure spring 10 is provided.
The pressing plate 9 is urged in the direction of the feed roller 43 by an elastic force of zero.

On the sheet material supply side of the cassette tray 11, sheet materials are separated and one by one, as shown in FIG.
4 is provided with a separation pad 8 for feeding the same. Also,
At the rear end of the cassette tray 11 in the sheet feeding direction, a rear end regulating member 12 configured to be movable in the sheet feeding direction with respect to the cassette tray 11 is disposed. Is brought into contact with the rear end of the sheet material to regulate the position of the rear end of the sheet material.

The sheet material stacked on the sheet cassette 1 is provided at the side end of the cassette tray 11 parallel to the sheet material feeding direction so as to be movable in the width direction with respect to the cassette tray 11. A left end regulating member 2 as a reference member and a left end regulating member 2 as a reference member that abuts one side end of the sheet material such that a writing position of an image formed on the sheet material always becomes a predetermined position from the sheet material side end surface. Protection member 3 for protecting the edge of the cassette tray 11, a right end restriction member 4 as a width restriction member provided to be movable in the width direction with respect to the cassette tray 11, and a right protection member 5 for protecting the edge of the right end restriction member 4.
A pressing spring 6 as an urging member for urging the stacked sheet material to the left end regulating member 2 is fixed to the right end regulating member 4. The position of the side end of the sheet material is regulated by the means.

The pressure spring 6 is composed of a rear end 6a which comes into contact with the middle portion of the sheet material and a front end 6b which comes into contact with the front end of the sheet material. When biased to the member 2, the pressure spring distal end portion 6b biases the distal end portion of the sheet material to the left end regulating member 2 to adjust the posture of the sheet material.

The right protection member 5 is provided with a cam 7 which operates in conjunction with the lifting and lowering operation of the press contact plate 9.

Next, a description will be given of moving means for regulating the positions of both side edges of the sheet material according to the size of the sheet material to be stacked.

FIG. 2A shows a relatively wide sheet material 15.
Plane explanatory view showing a sheet material loading device when loading
FIG. 2B is an explanatory plan view showing the sheet material stacking apparatus when a relatively narrow sheet material 15 is stacked. In the following description of the drawings, the horizontal direction of the cassette tray 11 is defined toward the sheet feeding direction of the sheet material 15. That is, in FIG. 2, the upper side of the cassette tray 11 is described as a right side, and the lower side is described as a left side.

2 (a) and 2 (b), the left end regulating member 2 and the right end regulating member 3 provided on the left side and right side of the cassette tray 11 as the movement restricting means are the cassette tray. With reference to the center of the sheet material 11, the sheet material 15 can be moved relative to the cassette tray 11 in the width direction of the sheet material 15.

The left end regulating member 2 and the right end regulating member 4
The racks 13a and 13b are provided below the press-contact plate 9 and protrude horizontally in the center direction of the cassette tray 11, respectively. The racks 13a and 13b are also below the press-contact plate 9 and the cassette. The tray 11 is configured to engage with a pinion 14 rotatably provided at a central position of the tray 11.

When both or one of the left end regulating member 2 and the right end regulating member 4 is moved in the width direction of the sheet material, the pinion 14 engaged with the racks 13a and 13b rotates.

Here, since the tooth pitches of the racks 13a and 13b are formed to be equal to the tooth pitch of the pinion 27, the movement of the left end regulating member 2 and the right end regulating member 4 around the pinion 14 is performed. The distances are equal.

In this way, the rear end regulating member 12, the left end regulating member 2 and the right end regulating member 4 are respectively moved according to the size of the sheet material to be used, and the sheet material is placed on the pressure contact plate 9. One side end is abutted against the reference regulating means and laminated.

The pressing spring 6 to which the rear end regulating member 12, the left end regulating member 2 and the right end regulating member 4 are fixed is brought into contact with the rear end and the side end of the sheet, respectively. Is set so as to regulate the position of the end of.

In this state, the sheet cassette 1 is moved to the apparatus main body 40.
(See FIG. 10), the sheet material stacked on the paper feed cassette 1 is fed as described in the conventional example, and an image is formed by the image forming means.

Next, a description will be given of a cam 7 provided on the right side protection member 5 as an engagement member that operates in conjunction with the pressure contact plate 9.

FIG. 3A is a side view and a cross-sectional view showing the sheet feeding cassette 1 when the stacked sheet materials 15 are fully loaded, and FIG. 3B is a state in which the stacked sheet materials 15 are slightly loaded. 2A and 2B are a side view and a cross-sectional view illustrating the sheet feeding cassette 1 at the time.

The cam 7 is formed integrally with the right side protection member 5 and is rotatably supported by a shaft 5 a disposed on an axis along the width direction of the sheet material. It is urged in the direction of lifting the plate 9.

A shaft 5 is provided between the cam 7 and the right protection member 5.
The pressure control member 17 is slidably disposed on the guide a. The pressure control member 17 has two springs 18 supported at the top and bottom at the tip. The spring 18 is inserted through guide holes provided through the right protection member 5 and the right end regulation member 4.
Is a distal end portion 6 of a pressure spring 6 fixed to the right end regulating member 4.
a.

As shown in FIG. 6, a gently changing projection 7b is provided on the pressure control member 17 side of the cam 7, and the height of the projection 7b is changed according to the rotation angle of the cam 7. It is set to change.

When the pressure control member 17 is pressed by the projection 7 b of the cam 7, the pressure control member 17 slides the shaft 5 a in parallel to the pressure spring 6 side, and By pressing the distal end portion 6b of the pressure spring 6, the pressure for urging the loaded sheet material 15 to the left end regulating member 2 changes.

As shown in FIG. 3 (a), when the sheet material 15 is fully loaded, the lever portion 7a of the cam 7 is pushed down by the pressure contact plate 9, and when the cam 7 rotates, the height of the projection 7b increases and the pressure increases. When the control member 17 is pushed in, the pressure for urging the sheet material 15 against the left end regulating member 2 increases.

Then, the sheet material 15 is fed and the stacking amount of the sheet material is reduced, and as shown in FIG.
As the number 5 becomes smaller, the seat pressure contact plate 9 is pushed upward by the pressure spring 10, so that the cam 7 is also
6, the height of the protrusion 7b is reduced.

Since the protrusion 7b is gradually changing, the pressure for urging the sheet material 15 against the left end regulating member 2 is continuously reduced as the load of the sheet material decreases.

In this manner, the pressure for urging the sheet material 15 against the left end regulating member 2 changes continuously according to the amount of the sheet material 15 loaded, and the end of the sheet material 15 is moved by an appropriate urging force. It becomes possible to energize.

Accordingly, the stacking position of the sheet material is adjusted to stabilize the conveyance of the sheet material, and the image forming position and the posture performed after the conveyance become constant.

(Second Embodiment) FIG. 4 is a drawing showing the configuration of a second embodiment of a sheet material stacking apparatus to which the present invention is applied. Reference numeral 20 denotes a sheet feeding cassette as a sheet material stacking device, which is configured to stack sheet materials such as recording papers of different sizes such as A3 and A4 and to be detachably attached to the main body of the image forming apparatus 40. In the present embodiment, a sheet feed cassette is provided with a center as a reference with respect to the center of the stacked sheet materials.

In FIG. 4, inside the cassette tray 11 constituting the framework of the paper feed cassette 20, there are provided pressure contact plates 9 rotatably mounted on both side walls of the cassette tray 11.

Further, on the bottom surface of the cassette tray 11 on the sheet material feeding side, a pressure contacting a predetermined position on the back surface of the pressure contact plate 9 corresponding to the feeding roller 43 of the image forming apparatus 40 shown in FIG. A spring 10 is provided.
The urging plate 9 is urged in the direction of the feed roller 43 by the elastic force of.

The sheet supply side of the cassette tray 11 is provided with a separation pad 8 for separating the sheet material and supplying it one by one to the sheet material transport path 44 in FIG. At the rear end of the cassette tray 11 in the sheet feeding direction, a rear end regulating member 12 configured to be movable in the sheet feeding direction with respect to the cassette tray 11 is disposed. It is configured to contact the rear end of the sheet material to regulate the position of the rear end of the sheet material.

The sheet material stacked on the sheet feed cassette 20 is provided at the side end of the cassette tray 11 parallel to the sheet material feeding direction so as to be movable in the width direction with respect to the cassette tray 11. A left end regulating member 21 serving as a reference regulating means for abutting one side end of the sheet material so that a writing start position of an image formed on the material is always a predetermined position from the sheet material side end surface, and a width relative to the cassette tray 11. Right end regulating member 2 which is a movement regulating means provided so as to be movable in the direction
2, a pressing spring 6 for urging the loaded sheet material to the left end regulating member 21 is fixed to the right end regulating member 22. It is configured to regulate the position of the side end.

The pressure spring 6 comprises a rear end 6a which comes into contact with the middle part of the sheet material and a front end 6b which comes into contact with the front end of the sheet material. The pressing spring tip 6b urges the leading end of the sheet material to the left end regulating member 2 to adjust the posture of the sheet material.

The right end regulating member 22 is provided with a cam 23 which operates in conjunction with the press contact plate 9.
In the same manner as in the first embodiment, the rear end regulating member 12, the left end regulating member 21, and the right end regulating member 22 are respectively moved according to the size of the sheet material to be used, and One side edge of the sheet material is abutted against the reference regulating means and laminated.

Then, the pressing spring 6 fixed to the rear end regulating member 12, the left end regulating member 21 and the right end regulating member 22 is brought into contact with the rear end and the rear end of the sheet material, respectively. Is set so as to regulate the position of the end of. When the sheet cassette 20 is mounted on the apparatus main body 40 in this state, an image is formed on the sheet material stacked on the sheet cassette 20 as described in the conventional example.

Next, the cam 23 provided on the right end regulating member 22 and operating in conjunction with the press contact plate 9 will be described. FIG. 5A is a side view and a cross-sectional view showing the sheet material stacking device when the sheet materials 15 stacked in the sheet cassette are full, and FIG. 5B is a diagram illustrating the sheet material 15 stacked in the sheet cassette. FIGS. 4A and 4B are a side view and a cross-sectional view showing the sheet material stacking device when the sheet is in a small loading state.

The cam 23 is formed integrally with the right end regulating member 22 or is rotatably supported by a shaft 22a fixed separately from the cam 23.
Is biased in the direction of lifting.

A pressure control member 17 is arranged between the cam 23 and the right end regulating member 22 so as to be slidable with the shaft 22a as a guide. Two springs 18 are supported at the top of the pressure control member 17 at the top and bottom, and the spring 18 is fixed to the right end regulation member 22 through a guide hole provided through the right end regulation member 22. It is in contact with the tip 6a of the pressure spring 6.

As shown in FIG. 7, a protrusion 23b is provided on the pressure control member 17 side of the cam 23,
The projection 23b is set so as to press the pressure control member 17 in accordance with the rotation angle of 3. And the pressure control member 1
7 is pressed by the projection 23b of the cam 23, the pressure control member 17 slides the shaft 22a in parallel to the pressure spring 6 side, and the distal end 6b of the pressure spring 6 via the spring 18. By pressing, the pressure for urging the loaded sheet material 15 against the left end regulating member 21 increases.

As shown in FIG. 5 (a), when the sheet material 15 is fully loaded, the lever 23a of the cam 23 is pushed down by the pressure contact plate 9, the cam 23 rotates, and the projection 23b pushes the pressure control member 17 in. , The sheet material 15 to the left end regulating member 2
The pressure applied to the pressure increases.

Then, the sheet material 15 is fed and the stacking amount of the sheet material is reduced, and as shown in FIG.
As the number 5 becomes small, the seat pressure contact plate 9 is pushed upward by the pressure spring 10 so that the cam 7 is also pressed by the urging spring 16.
As a result, the protrusion 23b is disengaged from the pressure control member 17, and the pressure for urging the sheet material 15 to the left end regulating member 2 decreases.

In this way, the pressure for urging the sheet material 15 to the left end regulating member 2 changes stepwise according to the amount of the sheet material 15 loaded. Note that the pressure can be changed in any number of stages.

(Third Embodiment) FIG. 8 is a drawing showing the configuration of a third embodiment of the sheet material stacking apparatus according to the present invention. Reference numeral 30 denotes a sheet feeding cassette serving as a sheet material stacking device, which is configured to stack sheet materials such as recording papers of different sizes such as A3 and A4 and to be detachable from the image forming apparatus main body. still,
In the present embodiment, a paper feed cassette is provided on the basis of the center of a sheet material to be stacked.

In FIG. 8, inside the cassette tray 11 constituting the framework of the paper feed cassette 30, there are provided pressure contact plates 9 rotatably mounted on both side walls of the cassette tray 11. On the bottom surface of the cassette tray 11 on the sheet material feeding side, a pressing spring 10 which abuts on a predetermined position on the back surface of the pressing plate 9 corresponding to the feeding roller 43 of the image forming apparatus 40 shown in FIG. The pressing plate 9 is urged in the direction of the feed roller 43 by the elastic force of the pressing spring 10.

The sheet supply side of the cassette tray 11 is provided with a separation pad 8 for separating the sheet material and supplying it one by one to the sheet material transport path 44 in FIG. At the rear end of the cassette tray 11 in the sheet feeding direction, a rear end regulating member 12 configured to be movable in the sheet feeding direction with respect to the cassette tray 11 is disposed. The member 12 is configured to contact the rear end of the sheet material to regulate the position of the rear end of the sheet material.

The sheet material stacked on the sheet cassette 30 is provided at the side end of the cassette tray 11 parallel to the sheet material feeding direction so as to be movable in the width direction with respect to the cassette tray 11. A left end regulating member 2 serving as a reference regulating means for abutting one side end of the sheet material so that a writing position of an image formed on the sheet material always becomes a predetermined position from the sheet material side end surface; Protection member 3, which protects the edge of the cassette tray 11, a right-side restriction member 4 which is a movement restriction means provided so as to be movable in the width direction with respect to the cassette tray 11, and a right-side protection member 5 which protects the edge of the right-side restriction member 4. A pressing spring 6 for urging the loaded sheet material to the left end regulating member 2 is fixed to the right end regulating member 4. Side end position It is configured to regulate.

The pressure spring 6 is composed of a rear end 6a which comes into contact with the middle part of the sheet material and a front end 6b which comes into contact with the front end of the sheet material. When biased to the member 2, the pressure spring distal end portion 6b biases the distal end portion of the sheet material to the left end regulating member 2 to adjust the posture of the sheet material.

The right protection member 5 is provided with a cam 7 which operates in conjunction with the pressure plate 9 and a pressure control member 17. Further, a cam lever 3 is provided outside the cam.
1 is arranged, engages with a cam groove 34 formed on the bottom surface of the cassette tray 11 via a link lever 33, and is configured to operate in conjunction with the position of the right end regulating member 4. ing.

Then, in the same manner as in the first embodiment, the rear end regulating member 1 corresponds to the size of the sheet material to be used.
2 and the left end regulating member 21 and the right end regulating member 22 are respectively moved, and one side end of the sheet material is abutted against the reference regulating means on the press contact plate 9 and laminated.

The pressing spring 6 fixed to the rear end regulating member 12, the left end regulating member 21 and the right end regulating member 22 is brought into contact with the rear end and the rear end of the sheet material, respectively. Set to restrict the position of the part.

In this state, the paper feed cassette 30 is
When it is set to 0, an image is formed on the sheet material stacked on the sheet cassette 30 as described in the conventional example.

Next, the movement of the cam lever 31 disposed outside the cam 7 will be described. FIG. 8A is an explanatory plan view showing a sheet material stacking device when a relatively wide sheet material 15 is stacked, and FIG. 8B is a sheet material when a relatively narrow sheet material 15 is stacked. It is a plane explanatory view showing a loading device.

FIG. 9A is a side view and a cross-sectional view showing a sheet material stacking apparatus when a relatively wide sheet material 15 is stacked on the sheet cassette, and FIG. It is a side view and a sectional view showing a sheet material loading device when a narrow sheet material 15 is loaded.

The cam 7 is rotatably supported by a shaft 5a formed integrally with the right side protection member 15, and the biasing spring 1
6, the pressing plate 9 is urged in a lifting direction. A pressure control member 17 is disposed between the cam 7 and the right protection member 5 so as to be slidable with the shaft 5a as a guide.

The pressure control member 17 has a spring 18 at its tip.
Are supported at two upper and lower positions, and the distal end of the pressure spring 6 in which the spring 18 is fixed to the right end regulating member 22 through a guide hole provided through the right protecting member 5 and the right end regulating member 4. It is in contact with the portion 6a.

A cam lever 31 rotatably mounted on the shaft 5a outside the cam 7 is provided with a flange 32 to rotate the shaft 5a.
It is locked so that it does not come off. Cam lever 3
One end of a link lever 33 is engaged with one of the ends, and the other end of the link lever 33 is engaged with a cam groove 34 formed in the cassette tray. The cam lever 31 is provided with a cam portion 31a. When the cam lever 31 rotates, the cam portion 31a comes into contact with the flange 32, and the cam lever 31 moves to the cam 7 side. ing.

When the sheet material 15 is wide as shown in FIG. 8A, the tip of the link lever 33 is engaged with one end 34a of the cam groove 34, so that as shown in FIG. 9A. The cam lever 31 pivots to move the cam portion 31a to the flange 32.
a, the cam lever 31 moves to the cam 7 side, and pushes the cam 7 into the pressure control member 17.

When the pressure control member 17 is pressed by the cam, the pressure control member 17 slides the shaft 5a in parallel with the pressure spring 6 side, and the pressure control member 17 Sheet material 1 loaded by pressing the tip 6b of
5 urges the left end regulating member 2.

When the width of the sheet material 15 is narrow as shown in FIG. 8B, the tip of the link lever 33 is engaged with one end 34b of the cam groove 34, so that as shown in FIG. 9B. The cam lever 31 does not rotate, and the pressure for urging the stacked sheet materials 15 against the left end regulating member 2 becomes low.

Since the cam portion 31a of the cam lever 31 is formed with a gentle slope, the pressure for urging the sheet material 15 against the left end regulating member 2 depends on the width of the sheet material. Is high, and changes continuously low when it is narrow.

Further, as described in the first embodiment, the cam 7 operates in conjunction with the press contact plate 9 so that the sheet material 15 can be moved by the left end regulating member 2 depending on the stacking height of the sheet material 15. The pressure applied to changes.

[0099]

According to the present invention as described above, the sheet material is provided with the urging force changing means for changing the urging force of the urging means for urging the sheet material in conjunction with the sheet material stacking means. When the stacking amount of the sheet material is large, the urging force is high, and when the stacking amount of the sheet material is small, the urging force is reduced, so that the sheet material is securely provided in the sheet material stacking device regardless of the sheet material stacking amount. It became possible to energize.

Further, since the weight of the sheet material to be stacked varies depending on the size of the sheet material, the urging force is increased when the width of the sheet material is large, and the urging force is increased in accordance with the size of the sheet material. When the width of the sheet material is small, the urging force is reduced, so that the sheet material can be surely urged to the reference member regardless of the loaded weight of the sheet material.

Therefore, the stacking position of the sheet material is stabilized, and the positional accuracy of the formed image is improved. In addition, there is no need for the user to press the sheet material against the reference plate when the sheet material is loaded, and the operability is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a configuration of a first embodiment of a sheet material stacking apparatus according to the present invention.

FIG. 2 is an explanatory plan view showing the sheet material stacking device according to the first embodiment;

FIG. 3 is a side view and a cross-sectional view showing the sheet material stacking device according to the first embodiment.

FIG. 4 is an explanatory diagram showing a configuration of a second embodiment of the sheet material stacking device of the present invention.

FIG. 5 is a side view and a cross-sectional view illustrating a sheet material stacking device according to a second embodiment.

FIG. 6 is a supplementary explanatory diagram of the first embodiment.

FIG. 7 is a supplementary explanatory diagram of the second embodiment.

FIG. 8 is an explanatory view showing a configuration of a third embodiment of the sheet material stacking device of the present invention.

FIG. 9 is a side view and a cross-sectional view showing a sheet material stacking device according to a third embodiment.

FIG. 10 is an explanatory cross-sectional configuration diagram of an image forming apparatus provided with a sheet material stacking apparatus.

FIG. 11 is an explanatory view of a conventional example.

[Description of Signs] 1 Sheet material stacking device 2 Left side regulating member 3 Left side protecting member 4 Right side regulating member 5 Right side protecting member 6 Pressure spring (biasing member) 7 Cam (biasing force changing means) 8 Separation pad 9 Pressure contact Plate 10 pressure spring 11 cassette tray 12 rear end regulating plate 13 rack 14 pinion 15 sheet material 16 urging spring 17 pressure control member 18 spring 20 sheet material loading device 21 left end regulating member 22 right end regulating member 23 cam 30 sheet material Loading device 31 Cam lever 32 Flange 33 Link lever 34 Cam groove 35 Cam 40 Image forming device 41 Sheet material loading device 42 Cassette tray 43 Feed roller 44 Transport path 45 Transport roller pair 46 Registration roller pair 47 Developing cartridge 48 Scanner unit 49 Drum 50 Transfer roller 51 Fixing device 2 discharge roller pair 53 discharge roller pair 54 discharge tray 55 Controller Board

Continued on the front page F term (reference) 2C059 AA05 AA09 AA42 DD07 2H072 BA03 BA12 JA04 3F343 FA02 FB01 GB01 GC01 GD01 HB03 HE03 HE11 JA01 JD08 LC20 MA22 MB12 MC12

Claims (16)

[Claims] 1. A sheet material stacking means for stacking and raising and lowering a sheet material, a reference member arranged on the sheet material stacking means, and positioning one end position in the width direction of the stacked sheet material; A width regulating member disposed at the other end position in the width direction of the sheet material facing the reference member; and an urging member for urging the sheet material stacked on the sheet material stacking means toward the reference member side. And a biasing force changing unit that changes the biasing force of the biasing member in accordance with the loading amount of the sheet material. 2. A sheet material stacking means for stacking and raising and lowering a sheet material, a reference member arranged on the sheet material stacking means, and positioning one end position of the stacked sheet material in the width direction; A width regulating member disposed at the other end position in the width direction of the sheet material facing the reference member; and an urging member for urging the sheet material stacked on the sheet material stacking means toward the reference member side. Wherein at least one of the reference member and the width regulating member is disposed so as to be movable in a width direction according to a width of the sheet material stacked on the sheet material stacking means. A sheet material stacking device comprising: an urging force changing unit that changes an urging force of an urging member according to a width of a sheet material. 3. A sheet stacking means for stacking and raising and lowering a sheet material, a reference member disposed on the sheet stacking means and positioning one end of the stacked sheet material in a width direction, and the sheet material A width regulating member disposed at the other end position in the width direction of the sheet material stacked on the stacking means; and a biasing member supported by the width regulating member and biasing the sheet material toward the reference member. In the sheet material stacking device provided, at least one of the reference member and the width regulating member is disposed so as to be movable in a width direction according to a width of the sheet material stacked on the sheet stacking means, and the urging member is provided. And a biasing force changing unit that changes the biasing force according to the load amount of the sheet material and the width of the sheet material. 4. The sheet material stacking apparatus according to claim 1, wherein the urging force changing means changes the urging force of the urging member in conjunction with the elevating operation of the sheet material stacking means. 5. The urging means has a spring which presses a side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to its elevation position to rotate the spring. The sheet loading device according to claim 1, further comprising a cam that changes a force of the sheet. 6. The sheet stacking device according to claim 2, wherein the urging force changing unit changes the urging force of the urging member in conjunction with the movement of the width regulating member. 7. The urging means has a spring for pressing a side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to a moving position of the spring to rotate the spring. 7. The sheet stacking device according to claim 2, further comprising a cam for changing the force of the sheet. 8. The apparatus according to claim 3, wherein said urging force changing means changes the urging force of said urging member in conjunction with the elevating operation of the sheet stacking means and the moving operation of said width regulating member. The sheet material loading device described in the above. 9. The urging means has a spring which presses a side end of the sheet material, and the urging force changing means engages with the sheet material stacking means and rotates according to its elevation position to rotate the spring. 9. The sheet material according to claim 3, further comprising a cam that changes the force of the spring and that rotates in accordance with the movement position of the spring by changing the force of the spring by engaging with the width regulating member. Loading device. 10. The cam is rotatably supported about an axis along the width direction of the sheet material, and the cam is provided with a projection that can abut the spring. 10. The sheet material stacking apparatus according to claim 5, wherein a force of the spring is changed by changing a bending amount. 11. The apparatus according to claim 1, wherein the urging force changing means changes the urging force of the urging member continuously in accordance with a position at which the sheet stacking means moves up and down or a position at which the width regulating member moves. The sheet loading device according to any one of 1 to 10. 12. The apparatus according to claim 1, wherein said urging force changing means changes the urging force of said urging member in a stepwise manner in accordance with an elevating position of said sheet stacking means or a moving position of said width regulating member. The sheet loading device according to any one of 1 to 10. 13. The apparatus according to claim 1, wherein said urging force changing means is provided on said width regulating member.
The sheet loading device according to any one of claims 1 to 7. 14. The sheet stacking device according to claim 13, wherein the urging force changing unit is provided on a protection member that protects an edge of the width regulating plate attached to the width regulating member. . 15. An image forming apparatus comprising: the sheet material stacking device according to claim 1; and image forming means for forming an image on a sheet material fed from the sheet material stacking device. apparatus. 16. The image forming apparatus according to claim 15, wherein the sheet stacking device is a sheet cassette detachably mounted on an image forming apparatus main body.