JPH0873058A - Sheet cassette and image forming apparatus - Google Patents

Abstract

(57) [Abstract] [Purpose] It is not necessary to attach a dust cover to the paper feed cassette, and the opening of the paper feed cassette protruding from the main body of the device is covered with the dust cover. [Structure] A paper feed cassette dust cover mounted on an image forming apparatus main body has an engaging portion projecting into a mounting / dismounting path of the paper feed cassette, and when the paper feeding cassette is mounted on the main body of the apparatus, the engaging portion feeds The dust cover is extended by engaging the cassette.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed cassette cover device and an image forming apparatus such as a copying machine, a printer and a facsimile, which is equipped with the cover device.

[0002]

2. Description of the Related Art Conventionally, a paper feed cassette is detachably attached to a main body of an image forming apparatus.

FIG. 6 schematically shows an electrophotographic copying machine 1 as an example of an image forming apparatus using such a paper feed cassette. The copying machine 1 shown in the figure has an image forming apparatus main body (hereinafter simply referred to as "apparatus main body") having an image forming unit.
It is equipped with 2. A paper feed cassette 3 for stacking the transfer sheets S is attached to the lower part of the apparatus main body.

The sheet feeding cassette 3 is provided with a box-shaped cassette tray 3b, and an intermediate plate 3a whose tip (on the right side in the figure) is biased by a compression spring 3c. A transfer sheet S, which is positioned by a regulating member 3d that regulates the rear end of the transfer sheet and a separation claw 3e that separates the transfer sheet S, is stacked on the intermediate plate 3a. The apparatus main body 2 is provided with a half-moon shaped feeding roller 6, and the feeding roller 6 is the intermediate plate 3a.
The uppermost transfer sheet S of the upper transfer sheets S is brought into contact with and the transfer sheet S is fed to the image forming section 5. Further, transport rollers 7 and 9 are provided downstream of the transfer sheet S being fed. Further, a scanner 10 that emits a laser beam L and a mirror 11 that reflects a laser are arranged above the apparatus body 2. The image forming unit 5, that is, the photosensitive drum 5a on which the image is written by being irradiated with the laser beam L reflected by the mirror 11, and the toner attached to the image are provided at substantially the center of the apparatus main body 2. And a transfer unit 5c for contacting the photosensitive drum 5a and transferring the toner adhering to the photosensitive drum 5a onto the conveyed transfer sheet S. . A fixing device 12 for fixing the toner on the transfer sheet S is arranged downstream of the photosensitive drum 5a, and further downstream thereof, a pair of conveying rollers 13 and 15 and a discharge roller 16 are arranged. Further, a paper discharge tray 17 on which the transfer sheet S is placed is provided on the upper part of the apparatus main body 2. On the other hand, a hand gap 18 is provided on the right side of the apparatus main body of FIG.
The transfer sheet material S is conveyed to the image forming portion 5 through the sheet.

Under such a structure, the transfer sheet S placed on the middle plate 3a of the paper feed cassette 3 is fed by the feeding roller 6
When is rotated in the direction of arrow R, the sheets are fed while being separated one by one by the separating claw 3e. Then, the transfer sheet S is conveyed to the image forming section 5 via the conveying rollers 7 and 9, and after the image is formed, the toner is fixed by the fixing device 12, and further, the conveying roller pair 13 and 15 is formed.
The paper is ejected onto the paper ejection tray 17 through the paper ejection roller 16.

Here, as shown in FIG. 7, the paper feed cassette 3 mounted on the apparatus main body 2 has a box-shaped cassette tray 3b, and an opening for replenishing the transfer sheet S is provided on the entire upper surface. Have. Further, as shown in FIG. 6, when the paper feed cassette 3 is mounted from the side of the device main body 2 along with the recent miniaturization of the device main body 2, a part of the paper feed cassette 3 is partially removed. May project from the opposite side.
In particular, in the case of a universal cassette, since the inner partitioning position is changed to accommodate transfer sheets S of various sizes, the size of the paper feed cassette 3 is the largest of the transfer sheets S. Part of the opening tends to protrude from the main body 2 of the apparatus, and a part of the opening facing upward also protrudes from the side surface of the main body 2. Therefore, foreign matter such as dust enters through the opening of the protruding portion of the paper feed cassette. When foreign matter enters the paper feed cassette 3, not only is the transfer sheet S contaminated, but also when the paper is fed from the paper feed cassette 3, the foreign matter that has entered between the feeding roller 6 and the transfer sheet S feeds the sheet. The roller 6 may slip, and the transfer sheet S may not be conveyed properly.

Therefore, in order to prevent foreign matters such as dust from entering the paper feed cassette even if the paper feed cassette 3 is left attached to the apparatus main body 2, the paper feed cassette 3 will be described with reference to FIGS.
As shown in FIG. 3, a detachable dust cover 3f is attached to the opening of the cassette for each paper feed cassette to effectively prevent foreign matter from entering.

[0008]

However, the dust cover 3f is required for each paper feed cassette. Further, the dust cover 3f needs to be removed when the transfer sheet S is replenished and then reattached after the replenishment, so that the attaching / detaching operation becomes complicated.

Therefore, the present invention provides a paper feed cassette cover and an image forming apparatus in which it is not necessary to attach a dust cover to each paper feed cassette, and therefore it is not necessary to attach and detach the dust cover when replenishing the transfer sheet S. Especially.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and when the paper feed cassette (3) is attached to the apparatus body (2), the projecting opening of the apparatus body (2) is provided. In a cover device for covering a protruding portion of the paper feed cassette (3) protruding from the device body (33), the cover device from the device body (2) is interlocked with the mounting operation of the paper feed cassette (3) to the device body (2). The paper cassette (3) that projects
Cover (31, 41, 51, 6 for covering the upper surface of the protruding portion of the
1) and a cover device comprising:

[0011] Preferably, the cover (31) is an engaging portion (31a) projecting into the attachment / detachment path of the paper feed cassette (3).
It is preferable that the cover (31) be extended by engaging the engaging portion (31a) with the paper feed cassette (3) at the time of mounting.

Further, when the paper feed cassette (3) is not attached to the apparatus body (2), a return means (63) for accommodating the cover (31) in the apparatus body (2) is provided. I hope

Further, when the paper feed cassette (3) is not attached to the apparatus main body (2), the cover (31) is provided.
Preferably functions as a lid for closing the paper feed cassette projecting opening (33) of the apparatus body (2).

It is preferable that the cover (31) is formed in a plate shape and a slide guide (32) is provided as a supporting means of the cover (31).

In particular, the returning means (63) may be a spring interposed between the plate-shaped cover (31) and the apparatus main body (2).

In particular, the cover (31) is formed in a plate shape, and a pivotal support (52) is provided as a support means for the cover (31).
And a plate-like cover (31) is swingable,
It is preferable to take a position that covers the paper feed cassette (3) when it is attached and a position that closes the paper feed cassette protrusion port (33) when not attached.

Further, the cover (31) may be formed in the shape of a transfer sheet, and a winding member (42) may be provided as a supporting means of the cover (31).

The present invention can also be applied to an image forming apparatus provided with the cover device.

[0019]

Based on the above construction, the apparatus body (2) is interlocked with the mounting operation of the sheet feeding cassette (3) to the apparatus body 2.
The dust covers (31, 41, 51, 61) are fed out from the side, and cover the part of the opening on the upper surface of the paper feed cassette (3) protruding from the apparatus main body (2) from above.

At this time, the dust covers (31, 41, 5)
When the engaging portion (31a) is fitted to the (1, 61), the engaging portion (31a) engages with the sheet feeding cassette (3), so that the dust cover (31, 41, 51, 6
1) is paid out.

When the paper feed cassette (3) is not attached to the apparatus body (2), the dust cover (31,
41, 51, 61) are housed in the device body (2) by the returning means (63), and the dust cover (31, 41, 51, 61) is a cassette projecting port of the device body (2). It has a function as a lid for closing (33).

[0022]

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the same reference numerals are given to the members having the same functions as those of the conventional art, and the description thereof will be omitted.

(Embodiment 1) As shown in FIG. 1, as in the conventional example, the uppermost stacking sheet on the intermediate plate 3a arranged in the sheet feeding cassette 3 mounted on the apparatus main body 2 is as follows. The toner is fixed by the fixing device 12 after being conveyed to the image forming unit 5 by the feeding roller 6 and the conveying rollers 7 and 9 and subjected to the image forming process. Then, the transport rollers 13, 15,
The paper is ejected to the paper ejection tray 17 via the paper ejection roller 16. The sheet feeding cassette 3 is detachable, and the apparatus main body 2 is configured such that the sheet feeding cassette 3 is attached and detached from a mounting portion on the right side of the apparatus main body in FIG.

2A to 2D show the dust cover 3
1 shows a device main body 2 which is formed in a plate shape and is provided with a slide guide 32 as a means for supporting the dust cover 31.

FIG. 2A is a sectional view of the apparatus main body 2 in a state where the paper feed cassette 3 is not attached, and FIG. 2B is a perspective view of the apparatus main body 2 in such a state.

In the upper and lower sides of the image forming apparatus main body 2 in the vicinity of the paper feed cassette protruding port 33, 1 is attached in the paper feed cassette attaching / detaching direction.
A pair of slide guides 32 are provided, and a plate-like dust cover 31 is provided on the slide guides 32 so as to be slidable in the directions of arrows O and P. The tip end of the dust cover 31 has an engaging portion 31a that is bent downward and protrudes into the attachment / detachment path of the sheet feeding cassette 3.

FIG. 2 (c) is a sectional view of the apparatus main body 2 in the mounted state of the paper feed cassette 3, and FIG. 2 (d) is a perspective view in this state.

When the paper feed cassette 3 is inserted from the side of the main body, the engaging portion 3 of the dust cover is formed near the cassette projecting opening 33.
1a engages with the front end portion 35 of the sheet feeding cassette 3, and when the insertion is further continued, the dust cover 31 is extended in the direction of the arrow O, and the upper surface opening of the sheet feeding cassette 3 protruding from the apparatus main body 2 is dusted. Covered by the cover 31.

When the paper feed cassette 3 is removed, the operator manually pushes back the dust cover 31 to store the dust cover 31 in the apparatus main body 2.

The engaging portion 3 at the tip of the dust cover 31
As shown in FIG. 5, which will be described later, 1a may be configured to completely cover the paper feed cassette projecting opening 33 when the paper feed cassette 3 is not mounted.

(Embodiment 2) In FIGS. 3A to 3D, the dust cover 41 is in the form of a sheet, and an apparatus main body provided with a winding member 42 as a means for supporting the sheet-like dust cover 41. 2 is illustrated.

FIG. 3A is a sectional view of the apparatus main body 2 in a state where the paper feed cassette 3 is not mounted, and FIG. 3B is a perspective view in this state.

A winding member 42 is arranged near the paper feed cassette protrusion 33 of the apparatus main body 2, and a sheet-like dust cover 41 is wound around the winding member 42. Further, at the tip of the sheet-like dust cover 41, a bar member 42a that engages with the protrusion 3g provided at the tip of the upper portion of the sheet feeding cassette 3 is provided as an engaging member.

FIG. 3 (c) is a sectional view of the apparatus main body 2 in the mounted state of the paper feed cassette 3, and FIG. 3 (d) is a perspective view in this state. When the paper feed cassette 3 is inserted into the apparatus main body 2, the bar member 42a at the front end of the sheet is engaged with the protrusion 3g at the front end thereof, the winding member 42 rotates in the direction of arrow Q, and the dust cover 41 is fed. Interlocked with the insertion operation of the paper cassette 3, the paper cassette 3 is gradually extended in the direction of the arrow O to cover the upper surface opening of the paper feed cassette 3 protruding from the apparatus main body 2. Then, when the paper feeding cassette 3 is taken out from the apparatus main body 2, the winding member 42 is interlocked with this and the winding member 42 is shown in FIG.
The sheet-like dust cover 4 rotates in the direction of arrow T shown in
1 is wound up by the winding member 42 which is urged by the elastic member, resulting in the state shown in FIGS. 3 (a) and 3 (b).

(Embodiment 3) Further, in the cover device shown in FIGS. 4 (a) to 4 (d), the dust cover 51 has a plate shape, and the pivot support portion 52 is provided as a means for supporting the dust cover. -Shaped dust cover 51 is swingable, and has a position M ₂ that covers the paper feed cassette 3 when the paper feed cassette 3 is mounted and a position that closes the paper feed cassette protrusion 33 when the paper feed cassette 3 is not mounted. Take M ₁ .

FIG. 4A is a sectional view of the apparatus main body 2 in a state where the paper feed cassette 3 is not mounted, and FIG. 4B is a perspective view in this state.

When the paper feed cassette 3 is not attached to the apparatus main body 2, the paper feed cassette protruding port 33 is closed by the weight of the dust cover.

FIG. 4C is a sectional view of the apparatus main body 2 with the paper feed cassette 3 attached, and FIG. 4D is a perspective view with such a state.

When the paper feed cassette 3 is inserted into the main body 2 of the apparatus, the dust cover 51 is gradually pushed out from the main body 2 of the apparatus around the pivot portion 52 by the tip of the paper feed cassette 3 and further inserted. Then, the paper feed cassette 3 is covered. On the other hand, when the paper feed cassette 3 is removed, the dust cover 51 descends in the direction opposite to the arrow K centering on the pivot portion 52 and covers the paper feed cassette projecting opening 33.

(Embodiment 4) FIGS. 5A to 5D show the plate-like dust cover 61 and the plate-like dust cover 61.
In the cover device having the slide guide 62 as a support means of the device, the tension spring 63 is provided between the device body 2 and the dust cover 61 so that the force in the arrow P direction is applied from the device body 2 to the extended dust cover 61. The cover device mounted between the two is shown.

FIG. 5 (a) is a sectional view of the apparatus main body 2 in which the paper feed cassette 3 can be placed without being attached, and FIG. 5 (b) is a perspective view in this state. Engagement part 61 of dust cover 61
a also serves as a lid of the paper feed cassette protruding port 33, and a tension spring 63 is mounted between the dust cover 61 and the apparatus main body 2. Since the biasing force of the tension spring 63 acts in the direction of arrow P, the dust cover 61 covers the paper feed cassette projecting opening 33 when the paper feed cassette 3 is not attached to the apparatus main body 2.

FIG. 5 (c) is a sectional view of the apparatus main body 2 when the paper feed cassette 3 is attached, and FIG. 5 (d) is a perspective view of such a state. The paper feed cassette 3 engages with the dust cover 61 in the vicinity of the paper feed cassette protrusion 33, and the tension spring 6
Against the biasing force of 3, the dust cover 61 gradually moves in the direction of the arrow O in association with the protrusion from the sheet cassette protrusion port 33.
It is paid out in the direction. As a result, the dust cover 61 covers the upper surface opening protruding from the main body of the paper feed cassette 3.

When the paper feed cassette 3 is pulled out from the apparatus main body 2, the dust cover 71 is pulled back to the paper feed cassette projecting opening 33 by the urging force of the tension spring 63 and stored in the apparatus main body 2, and also serves as a lid. Engaging part 61a
The paper feed cassette protruding port 33 is covered with.

[0044]

As described above, according to the present invention,
Without installing a dust cover for each paper cassette,
It is possible to prevent foreign matter such as dust from entering the portion of the paper feed cassette protruding from the main body when the paper feed cassette is attached to the apparatus main body. As a result, the transfer sheet is not contaminated, and when the transfer sheet is fed from the paper feed cassette, the feeding roller slips due to foreign matter that has entered between the feeding roller and the transfer sheet. It is possible to prevent a defective conveyance.

Further, it is possible to avoid the trouble of the operator removing the cover attached to the sheet feeding cassette when replenishing the transfer sheet and changing the type of the transfer sheet.

Furthermore, since it is not necessary to attach a dust cover to each paper feed cassette, the cost of the entire image forming apparatus including the paper feed cassette can be reduced.

When the dust cover is provided with an engaging portion,
The cover is extended in conjunction with the mounting operation of the paper feed cassette.

If the dust cover has a function as a lid that closes the cassette projecting port, dust will not enter the main body of the apparatus when the sheet cassette 3 is not installed, which may cause a failure of the apparatus. It will be prevented.

Further, if the dust cover device is provided with a return member, the dust cover is stored in the main body of the apparatus in conjunction with the removal of the paper feed cassette, and therefore the manual labor of storing the dust cover in the main body can be saved.

Further, in the case of the cover device using the winding member, it is possible to dispose the cover device for covering the paper feed cassette even if there is no space for mounting the cover device consisting of the slide guide and the supporting means in the main body of the device.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an entire image forming apparatus according to the present invention.

FIG. 2 is a cover device for a sheet feeding cassette mounted on the image forming main body according to the first exemplary embodiment of the present invention.

FIG. 3 is a cover device for a paper feed cassette mounted on an image forming main body according to a second embodiment of the present invention.

FIG. 4 is a cover device for a sheet feeding cassette mounted on an image forming main body according to a third exemplary embodiment of the present invention.

FIG. 5 is a cover device for a paper feed cassette mounted on an image forming main body according to a fourth embodiment of the present invention.

FIG. 6 is a vertical cross-sectional view showing the entire conventional image forming apparatus.

FIG. 7 is a cassette cover device mounted on a conventional paper feed cassette.

[Explanation of symbols]

 1 image forming apparatus (copying machine) 2 image forming apparatus main body 3 sheet feeding cassette 3a middle plate 3b cassette tray 3c compression spring 3d transfer sheet rear end regulating member 3e separation claw 3g sheet feeding cassette protrusion 5 image forming unit 6 feeding roller 610 Scanner 11 Mirror 12 Fixer 17 Paper Ejection Tray 31, 41, 51, 61 Dust Cover 31a Engagement Part 32 Support Means (Slide Guide) 33 Paper Feed Cassette Projection Port 41a Engagement Part (Bar Member) 42 Support Means (Winding) 52) Supporting means (pivotally supporting part) 61a Engaging part 62 Supporting means (slide guide) 63 Returning means (tension spring)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taku Goto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (9)

[Claims] 1. A cover device for covering a projecting portion of the sheet feeding cassette projecting from a sheet feeding cassette projecting port of the image forming apparatus body when the sheet feeding cassette is mounted to the image forming apparatus body, A cover device that covers a top surface of a protruding portion of the paper feed cassette that projects from the image forming apparatus main body in association with the mounting operation of the paper feed cassette. 2. The cover has an engaging portion that projects into a mounting / dismounting path of the sheet feeding cassette, and the cover is extended by engaging the engaging portion with the sheet feeding cassette at the time of mounting. The cover device according to claim 1, wherein: 3. The cover according to claim 1, further comprising a returning unit that stores the dust cover in the main body of the image forming apparatus when the paper feed cassette is not mounted in the main body of the image forming apparatus. apparatus. 4. The cover functions as a lid that closes the paper feed cassette protruding port of the image forming apparatus main body when the paper feeding cassette is not attached to the image forming apparatus main body. A cover device according to any one of items 1 to 3. 5. The cover device according to claim 1, wherein the cover is formed in a plate shape, and a slide guide is provided as a supporting means of the cover. 6. The cover device according to claim 3, wherein the returning means is a spring interposed between the plate-shaped cover and the image forming apparatus main body. 7. The cover is formed in a plate shape, and a pivotal support portion is provided as a supporting means of the cover so that the plate cover can swing, and a position that covers the upper surface of the paper feed cassette when the paper feed cassette is mounted. The cover device according to any one of claims 1 to 4, wherein the cover device has a position for closing the paper feed cassette protrusion when the paper feed cassette is not attached. 8. The cover device according to claim 1, wherein the cover is formed in a sheet shape, and a winding member is provided as a supporting means of the cover. 9. An image forming apparatus comprising the cover device according to any one of 1 to 8 above.