JPH11106059A - Sheet loading device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a scratch, bending or the like of an envelope by providing a roller protruded from a loading member surface for loading envelops to be freely rotated in the envelope feeding direction and greatly reducing sliding resistance by the roller when the envelope is loaded by being slid along the loading member surface. SOLUTION: For loading an envelope S onto an envelope special cassette 8, a middle plate 9 is pressed and the envelope S is inserted in the arrow direction from a rear side to a front side. The envelope S is moved ahead while rotating a roller 9 freely rotated in the middle plate 9, and when a user releases hand in a loaded state until the front wall 21 of a cassette 2 is reached, the middle plate 9 is pushed up by the pressure of a spring 11 and the upper surface of the envelope S is contacted with a height regulating projection 8d provided in a side regulating plate 8c and its loading is completed. Thus, sliding resistance between the middle plate 9 and the envelope S is reduced during loading, inconveniences such as scratches, bending or the like are eliminated, and operability during the loading of the envelope S is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking apparatus capable of stacking and storing a plurality of sheets such as cut sheets and envelopes of an image forming apparatus such as a copying machine and a printer, and an image forming apparatus using the same. is there.

[0002]

2. Description of the Related Art Conventionally, in the case of envelope feeding of an image forming apparatus such as a copying machine or a printer, there has been a manual sheet feeding device or the like, but there is a drawback that a small number of sheets cannot be fed.

[0003] Therefore, a conveying means dedicated to envelope feeding is provided in a cassette to cope with multi-sheet feeding.

[0004]

However, in the above-described conventional feeding apparatus, in order to prevent the envelope from twisting or bulging, a height pressing projection for restricting the sheet stacking height in the width direction restricting member. Is provided.

[0005] Therefore, when the envelope is mounted on the feeding device, the height pressing projection becomes a hindrance from directly above, so that the envelope has to be inserted from the downstream side to the upstream side in the feeding direction. At this time, since the envelope is mounted while rubbing the top surface of the sheet stacking member and the bottom surface of the envelope, the envelope may be scratched or broken, which may cause paper jams and image misalignment. In the case where the sheet is fed from the sheet stacking member to the image forming section in reverse, the image forming surface is the bottom surface of the envelope that is rubbed with the upper surface of the sheet stacking member.

In addition, the bottom surface of the envelope rubs against the upper surface of the sheet stacking member during feeding, so that there is the same problem as during insertion.

[0007] The present invention has been made to solve the above-mentioned problems of the prior art.
An object of the present invention is to provide a sheet stacking apparatus and an image forming apparatus capable of smoothly moving a sheet in a sheet conveyance direction by reducing friction between a sheet bottom surface and a sheet stacking member upper surface.

[0008]

According to the present invention, there is provided a rotary member rotatable in a sheet conveying direction protruding from a surface of a stacking member for stacking sheets. Features.

With this arrangement, when the sheet is slid along the surface of the stacking member, the sliding resistance is significantly reduced by the rotating member, so that scratches and breaks are prevented, and the operability is improved. I do.

In addition, even during conveyance, scratches and breaks of the sheet sliding along the surface of the stacking member are prevented.

Further, the transport load of the lowest sheet abutting on the surface of the stacking member can be reduced, and the transportability can be improved.

The member for regulating the sheet width direction is provided with a height regulating member for regulating the sheet stacking height direction.

As described above, in the case where the height regulating member is provided, the sheet must be slid along the surface of the stacking member to be mounted, which is particularly effective in such a case.

The sliding resistance at the time of feeding the sheet is greatest at the press-contact position of the feeding means. Therefore, it is effective to provide the rotating member at a position facing the feeding means.

Further, an image forming apparatus according to the present invention includes the above-described sheet stacking apparatus and image forming means for forming an image on a sheet fed from the sheet stacking apparatus.

By feeding the sheet into the image forming section in this manner, an image defect caused by a scratch or a break at the time of mounting the sheet can be prevented, and a high-quality image can always be formed.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

As the order of the description, first, the overall configuration of the image forming apparatus will be described, and then the configurations of the sheet stacking apparatus and the sheet feeding apparatus will be described.

[Overall Configuration of Image Forming Apparatus] In FIG. 5, an image forming apparatus main body A has a scanner section B serving as image reading means for reading image information on the image surface of a book document at an upper portion thereof, and a scanner section B at a lower portion thereof. It has an image forming section C serving as an image forming means, and further includes a sheet feeding device D attached to a lower portion thereof.

The scanner section B includes a scanning system light source 201, a platen glass 202, a document pressure plate 203 that can be opened and closed with respect to the apparatus main body A, a mirror 204, a lens 205, a light receiving element (photoelectric conversion element) 206, an image processing section, and the like. Is configured. Then, a book document, sheet document, or the like, such as a book, thick paper, or curled paper, is placed on the platen glass 202 with the document surface facing down. When the is pressed, the scanning system light source 201 scans the lower part of the platen glass 202 in the direction of arrow a in FIG. The image information of the document read by the scanning light source 201 is processed by an image processing unit, converted into an electric signal, and transmitted to the laser scanner 111.

Here, the image forming apparatus main body A functions as a copying machine when a processing signal of the image processing unit is input to the laser scanner 111, and functions as a printer when an output signal of the personal computer is input. If a transmission signal from a facsimile device of another device is input or a processing signal of the image processing unit is transmitted to a facsimile device of another device, the device functions as a facsimile device.

On the other hand, a sheet cassette 1 is mounted below the image forming section C, and the sheet cassette 1 is composed of a lower cassette 1a and an upper cassette 1b as one feeding unit. In this embodiment, three feeding units U1, U2, and U3 are mounted, and six cassettes are mounted. One upper feeding unit U1 is detachably attached to the apparatus main body A, and two lower feeding units U2 and U3 are detachably attached to the sheet feeding device D.

The sheets accommodated in the cassettes 1a and 1b are fed out by a pickup roller 3, which is a feeding rotating body as a feeding means, as will be described later, and a feed roller 4 and a retard roller 5 constituting a separating means. After the sheets are separated and fed one by one by the cooperative action of the rollers, the sheets are conveyed by conveying rollers 104 and 105 constituting a conveying means.
The sheet is guided to a registration roller 106, and is fed to the image forming section C by the roller 106 in synchronization with the image forming operation.

The image forming section C includes an electrophotographic photosensitive drum 1
12, an image writing optical system 113, a developing device 114, a transfer charger 115, and the like. And
A laser beam corresponding to image information emitted from the laser scanner 111 is scanned by the image writing optical system 113 on the surface of the photosensitive drum 112 uniformly charged by the charger to form a latent image. A toner image is formed by the developing device 114, and the toner image is transferred to the first surface of the sheet by the transfer charger 115 on the sheet conveyed in synchronization with the rotation of the photosensitive drum 112 by the registration roller 106.

In FIG. 5, reference numeral 117 denotes a conveying belt for conveying the sheet on which the toner image is formed, 118 denotes a fixing device, and 119 denotes a discharge roller. The sheet on which the toner image is formed is transported by the conveying belt 117 to the fixing device 11.
After being conveyed to the sheet 8 and heated and pressed to fix the toner image on the sheet surface, the sheet is discharged by a discharge roller 119 to a sorter 120 disposed outside the apparatus and stacked.

When an image is recorded on both sides of the sheet, the sheet discharged from the fixing device 118 is sandwiched by discharge rollers 119, and the discharge roller 119 is rotated in reverse when the rear end of the sheet passes the branch point 207. Then, after the sheet is once placed on the double-sided tray 121, the conveyance rollers 104,
The sheet that has been conveyed by 105 and reaches the registration roller 106, and the inverted sheet is formed with an image on the second surface in the same manner as described above, and then discharged and stacked on the sorter 120.

In the sheet feeding apparatus D, as described above, the sheets loaded in the lower cassette 1a or the upper cassette 1b are sequentially fed by the pickup roller 3, but the upper and lower cassettes 1a and 1b are sequentially fed. Are each configured as shown in FIG.

In FIG. 6, reference numeral 2 denotes a main cassette main body, which includes a pair of left and right side regulating members 2a for regulating the widthwise end of the sheet S1, and a rear end regulating member 2b for regulating the rear end of the sheet in the sheet feeding direction. A sheet storage portion is formed. The sheet accommodating portion is provided with an opening 2c, and an intermediate plate 6 is provided so as to cover the opening 2c. The intermediate plate 6 is rotatably supported about a hinge portion 7, and when the main cassette body 2 is mounted on the image forming apparatus main body, an intermediate plate pressing member (not shown) disposed below the opening 2c. ), And stops the sheet S1 stacked and accommodated on the middle plate 6 at a position where the sheet S1 can be fed by the pickup roller 3.

A sheet stacking device can be mounted on the main cassette 2.

[Description of Sheet Loading Apparatus and Sheet Feeding Apparatus] Next, the sheet loading apparatus and a sheet feeding apparatus to which the sheet loading apparatus is attached to feed a sheet will be described.

The middle plate 6 of the main cassette 2 can be attached to and detached from the hinge portion 7, and when the middle plate 6 is removed, the sheet of the present invention is attached to the cassette bottom plate 2e in the sheet accommodating portion as shown in FIG. Four fitting holes 2d are provided for detachably attaching the cassette 8 for envelopes, which is a loading device. On the other hand, the bottom plate 8a of the cassette 8 for exclusive use of the envelope has four pins 8b protrudingly formed corresponding to the insertion holes 2d.
By inserting or removing the pin 8b into or from the insertion hole 2d, the envelope-dedicated cassette 2 can be attached to and detached from the main cassette 2.

The envelope-dedicated cassette 8 is loaded with an envelope having a flap as a sheet or an envelope which easily expands, and feeds the envelope to the image forming means for use in printing an address or the like. Therefore, the sheet fed in the present embodiment is a concept including not only a so-called cut sheet but also an envelope and the like.

FIGS. 1 and 2 (a) schematically show the configuration of an envelope-dedicated cassette 8 as the sheet stacking device.

That is, the cassette 8 for exclusive use of the envelope comprises a bottom plate 8a fixed to the bottom plate 2e of the main cassette 2, and a bottom plate 8a.
A side regulating members 8c, 8c which are erected on a and regulate the widthwise end of the envelope S form an envelope accommodating portion. A middle plate 9 as a sheet stacking member is vertically movably accommodated in the envelope accommodating portion. Unlike the middle plate 6 of the main cassette 2, the middle plate 9 is not rotatably supported at the rear end, but is supported so as to be vertically movable in a state parallel to the bottom plate 8a. However, similarly to the middle plate 6 of the main cassette 2, the rear end may be rotatably supported via a hinge.

The middle plate 9 is provided between the middle plate 9 and the bottom plate 8a.
An urging spring 11 as an urging means for urging the intermediate plate 9 upward is interposed, and presses the intermediate plate 9 with a predetermined force against the pickup roller 3 as a feeding rotating body.

On the other hand, the intermediate plate 9 is provided with a roller 10 as a rotating member protruding from its loading surface. The roller 10 is rotatable in the direction in which the envelope is conveyed, and is disposed at two positions separated from each other in the sheet conveying direction, and the roller 10 disposed on the downstream side in the conveying direction is a pickup roller 3 serving as a feeding rotating body. Is provided at a position opposite to the above.

On the other hand, the left and right side regulating members 8c are provided with two height pressing projections 8d as height regulating members for regulating the sheet height.

When mounting the envelope S in the cassette 8 for exclusive use of the envelope, as shown in FIG. 2A, the middle plate 9 is pushed down, and the envelope S is inserted in the direction of the arrow from the rear to the front. .
The envelope S is advanced while rotating the rotatable roller 10 on the middle plate 9, and when the user releases his / her hand while being attached to the front wall 2 f of the cassette 2, the middle plate 9 is pushed up by the pressure of the spring 11. Then, the upper surface of the envelope S abuts against the height pressing projection 8d provided on the side regulating plate 8c, and the mounting is completed. The upper surface of the envelope S is pressed against the pickup roller 3 at the same time.

As a result, the sliding resistance between the middle plate 9 and the envelope S at the time of mounting is reduced, problems such as scratches and breakage are eliminated, and the operability at the time of mounting the envelope S is improved.

Next, at the time of transporting the envelope S, the pickup cassette 8 is mounted on the main cassette 2 and the pickup roller transports the envelope S to the nip of the pair of rollers 4 and 5 as shown in FIG. The roller 10 is arranged at a position facing 3.

The envelope-dedicated cassette 8 may be mounted on the main cassette 2 after the envelope S is set on the envelope-dedicated cassette 8 and then mounted on the main cassette 2. The envelope S may be set afterwards.

As a result, "feed failure", which has conventionally been a problem when the last paper (the lowermost sheet of the set paper) is fed, that is, the frictional resistance between the envelope S and the intermediate plate 9 is reduced by the envelope S and the pickup roller. In order to be larger than the frictional resistance of 3,
The phenomenon that the pickup roller 3 slips on the envelope and the envelope does not advance by a predetermined amount is solved. This is because, by arranging the roller 10 at a position facing the pickup roller 3, the frictional resistance between the envelope S and the intermediate plate 9 is reduced.
Is reduced by the driven rotation.

However, at this time, as a problem that is simultaneously concerned, as shown in FIG. 3B, a so-called "double feed" occurs in which two envelopes are simultaneously fed to the nip of the roller pair 4,5. In this case, the second (lower) envelope fed by double feeding is returned to the cassette 2 direction by the separation roller 5 rotating in the direction opposite to the rotation direction of the feeding roller 4. Further, since the roller 10 on the intermediate plate 9 also rotates in the direction opposite to the feeding direction, the envelope returns smoothly, and no problem occurs.

In the above-described embodiment, the bottom plate 8a of the envelope-dedicated cassette 8 is fixed to the main cassette 2. However, as shown in FIG. The plates 8c, 8c are directly mounted on the main cassette 8,
A spring 11 may be interposed between the middle plate 9 and the bottom plate 2e of the main cassette.

Although the present invention has been described with reference to the cassette 8 exclusively for envelopes, the present invention is not limited to envelopes but can be widely used as a stacking device for various sheet materials. For example, a roller as a rotating member may be provided on the middle plate 6 of the main cassette 2 as the loading member.

[0046]

As described above, according to the present invention,
Since the sheet stacking member is provided with a rotatable member capable of rotating the sheet in the sheet conveying direction, it is possible to prevent scratches, breakage, and the like when mounting the envelope, and to improve operability. Furthermore,
Since the transport load of the last sheet can be reduced, the transportability is improved.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an envelope-dedicated cassette as a sheet stacking device according to an embodiment of the present invention.

FIG. 2 is a sectional view when an envelope is mounted.

FIGS. 3A and 3B are cross-sectional views when an envelope is conveyed.

FIG. 4 is a schematic exploded perspective view showing the entire configuration of the main cassette.

FIG. 5 is a cross-sectional view illustrating a configuration example of an image forming apparatus to which the cassette of FIG. 4 is mounted.

FIG. 6 is a perspective view showing a main cassette.

[Explanation of symbols]

 Reference Signs List 3 Pickup roller (feeding means) 8 Cassette for exclusive use of envelope (sheet stacking member) 8a Bottom plate 8c Side regulating plate 8d Height holding projection (height holding member) 9 Medium plate 10 Roller (rotating member)

Claims (4)

[Claims] 1. A sheet stacking apparatus, comprising: a rotatable member that is rotatable in a sheet conveying direction and protrudes from a surface of a stacking member for stacking sheets. 2. The sheet stacking apparatus according to claim 1, wherein the member that regulates the sheet width direction includes a height regulating member that regulates the sheet stacking height direction. 3. The sheet stacking apparatus according to claim 1, wherein the rotating member is provided at a position facing a feeding unit that feeds the sheet from the sheet stacking member. 4. An image comprising: the sheet stacking device according to claim 1; and image forming means for forming an image on a sheet sent from the sheet stacking device. Forming equipment.