JP2501419Y2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an image forming apparatus having an image carrier such as a photosensitive drum.

(Prior Art) Conventionally, an image carrier (hereinafter, referred to as a photoconductor drum) and an image forming unit arranged so as to surround the photoconductor drum are provided as one type of image forming apparatuses such as a copying machine and a printer. There is known an image forming apparatus configured so that it can be detached from the apparatus body separately (Japanese Patent Laid-Open No. 63-21606).
No. 5 bulletin).

Further, in order to prevent a user from touching a new photosensitive drum when setting a new photosensitive drum, various image forming apparatuses are provided with a protective sheet or a protective cover around the photosensitive drum. Proposed (JP-A-57
-211181).

(Problems to be solved by the invention) By the way, in the above-described conventional image forming apparatus, if the protective sheet and the protective cover are not removed from the photosensitive drum after the photosensitive drum is set in the apparatus main body, the image forming process is performed. Could not be executed.

Therefore, in this type of conventional image forming apparatus, when the used photoconductor drum is removed from the image forming unit, the photoconductor drum contaminated with toner must be directly handled, so that the user's hand or the like cannot handle the toner. There was a problem that was contaminated with.

An image forming apparatus has been proposed in which a shutter member is provided at the exposed portion of the exposed photoconductor drum so that the user or the like does not directly touch the photoconductor drum when the image forming unit is replaced. .

However, also in this image forming apparatus, when the photosensitive drum is attached to or detached from the apparatus main body, the shutter member needs to be removed as in the above, and therefore the used photosensitive drum must be directly handled. Therefore, the above-mentioned problems could not be solved.

(Means for Solving the Problems) According to the present invention, in order to solve the above problems, an image forming unit surrounding an image carrier is detached from the image carrier and then attached to and detached from the apparatus main body. In the image forming apparatus configured as described above, the image carrier has a pair of substantially symmetrical protective covers that cover the image carrier except for a transfer portion facing the transfer charger so as to surround each half of the image carrier, One end of each protective cover is supported by the supporting member of the image carrier so as to be rotatable between a closed position that surrounds the image carrier and an open position that opens in both sides to expose the image carrier. At the same time, it has the habit of turning to the closed position, and opens and closes in conjunction with the attachment / detachment operation of the image forming unit and the image carrier, and when one of the protective covers occupies the open position, Part of the transfer paper that is transported toward the transfer site The structure has a guide surface.

(Operation) According to the present invention, since the guide surface of the transfer paper conveyed toward the photoconductor drum is formed on one side of the protective cover, the protective cover is provided with the peripheral surface of the photoconductor drum. The function of protecting and the function of guiding the transfer paper are provided.

Therefore, according to the present invention, when the photosensitive drum is attached to the image forming unit, the protective cover is used while being attached to the photosensitive drum without being removed from the photosensitive drum.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings.

An image forming apparatus embodying the present invention is, as shown in FIG. 1, a transfer charger 2, an image writing unit 3, a developing unit 4, a transfer charger, which are arranged so as to surround the periphery of a photosensitive drum 1. An image forming unit (process kit) 13 including the cleaning unit 6 and the cleaning unit 6 is provided.

Further, the apparatus body of this image forming apparatus is composed of a fixed portion 20 that is fixed and a movable portion 21 that is opened and closed with respect to this fixed portion 20, and this movable portion 21 with respect to the fixed portion 20. When opened, the photosensitive drum 1 is exposed from the apparatus main body.

That is, as shown in FIG. 2, the movable portion 21 rotates in the direction of the arrow a to expose the photosensitive drum 1 and the transfer charger charger 5 to the fixed portion 21 of the apparatus main body.

As a result, the photoconductor drum 1 can be taken out from the apparatus main body. Further, in association with the opening operation of the movable portion 21, the developing unit 4 rotates about the support shaft 14 in the direction of arrow b in FIG.
The housing 15 closes the opening of the cleaning unit 6 to prevent the toner from scattering when the image forming unit 13 is attached or detached.

By the way, in the conventional image forming apparatus, there is a problem that the used photoconductor drum 1 soiled with the toner must be directly handled when the photoconductor drum 1 is exposed as described above when the photoconductor drum 1 is removed. there were.

Therefore, in the image forming apparatus according to the present invention, as shown in FIG. 3, a pair of protective covers 30A, 30A,
The protective cover kit 30 having 30B is arranged to make the photosensitive drum 1 into a kit.

The protective cover kit 30 includes protective covers 30A and 30A, each of which is formed in a symmetrical shape so as to cover a substantially half circumference of the photosensitive drum 1.
B is arranged to be openable and closable on side plates 31 as a pair of supporting members that rotatably support the photosensitive drum 1. At this time, each of the protective covers 30A and 30B is arranged so as to expose only a portion of the photosensitive drum 1 corresponding to the transfer charger charger 5.

Further, as shown in FIG. 4, the protective covers 30A and 30B are respectively biased by springs 32 to have a turning tendency in a direction of surrounding and closing the peripheral surface of the photosensitive drum 1. There is.

Therefore, in this image forming apparatus, as shown in FIG.
The movable part 21 is opened, and the photosensitive drum 1 and the image forming unit are opened.
Since the photoconductor drum 1 is covered with the protective covers 30A and 30B in a state where the photoconductor drum 1 and 13 are separated, a user or the like does not directly touch the peripheral surface when the photoconductor drum 1 is attached or detached.

On the other hand, as shown in FIG. 1, these protective covers 30A and 30B have the movable portion 21 closed and the movable portion 21 closed with the photosensitive drum 1 and the image forming unit 13 mounted. It is released in conjunction with the movement.

Here, as shown in FIG. 4, a means for opening each of the protective covers 30A, 30B in conjunction with the closing rotation of the movable portion 21 is, for example, as shown in FIG. Each pin 33 laid in each protective cover 30A, 30B at the time of closing and rotating 21
Is configured to be pushed down against the elasticity of each spring 32.

Further, as described above, the movable portion 21 is closed and the photosensitive drum 1 and the image forming unit 13 are attached to the protective covers 30A and 30B, and the protective cover 30A, 30B is interlocked with the closing rotation of the movable portion 21. In the opened state, as shown in FIG. 1, guide surfaces 30a and 30b having a guide function for the transfer paper P conveyed toward the photosensitive drum 1 by the registration roller 16 are formed.

Therefore, each protective cover 30A, 30 in this image forming apparatus
B does not need to be removed from the photoconductor drum 1 each time when the photoconductor drum 1 and the image forming unit 13 are attached and detached.

By the way, in the above embodiment, an example in which the transfer is performed on the lower side of the photosensitive drum 1 has been shown, but the present invention, as shown in FIG. The image forming apparatus, such as a laser printer, configured to perform the operation may be implemented.

In this embodiment, the photosensitive drum 1 and the transfer charger 5, the movable portion 21 of the apparatus main body, and the image forming unit.
A fixed part 20 of the main body of the apparatus is arranged on the crocodile, and the movable part 21 is separated from the fixed part 20 at a portion indicated by a broken line in FIG. 1
The image forming unit 13 is attached and detached.

Further, each protective cover 30A, 30B in this embodiment,
Similar to the above-described embodiment, the movable portion 21 is opened and closed in conjunction with the opening / closing rotation of the movable portion 21, and the movable portion 21 is separated from the fixed portion 20 to close the protective covers 30A and 30B and close the periphery of the photosensitive drum 1. The surface is protected, and when the movable part 21 is attached to the fixed part 20, the protective covers 30A and 30B are opened to function as guide members for the transfer paper P.

At this time, of the protective covers 30A and 30B, the protective cover 3
0A is also used as a lower guide of the transfer paper P conveyed by the registration rollers 16, but the other protective cover 30B is
The transfer sheet P is flipped up and released to a position where it does not hinder the conveyance of the transfer sheet P.

Further, in this embodiment, as shown in FIG. 6, the transfer charger 5 is formed integrally with the protective cover kit 30.

Therefore, the protective cover kit 30 in this embodiment,
Since the peripheral surface of the photoconductor drum 1 is completely shielded from the outside and the transfer charger 5 can be replaced at the same time when the photoconductor drum 1 is replaced, the performance of the image forming apparatus can be maintained in a better state.

As described above, in the image forming apparatus according to the present invention, since the photosensitive drum 1 is covered with the protective covers 30A and 30B in the opened state of the movable portion 21 of the apparatus body, the photosensitive drum 1 and the image forming unit 13 are covered. It is possible to avoid the risk of the user's or service person's hand directly touching the peripheral surface of the photoconductor drum 1 during replacement.

As for the processing of the jammed paper around the photosensitive drum 1, as shown in FIG. 2, the movable portion 21 is opened and the protective cover kit 30 is exposed to release the pressure contact of the registration roller 16. , The registration roller 16 pulls out the transfer paper P from the surface. At this time, a part of the jammed paper may be sandwiched between the joints of the protective covers 30A and 30B.
It is desirable to preliminarily form a small gap that allows the movement of the.

According to the present invention, when removing the used photoconductor drum from the image forming unit, the photoconductor drum contaminated with toner can be replaced together with the protective cover kit. You don't have to handle the drums directly, and the hands of users will not be contaminated with toner.

Further, since at least one of the protective covers has a transfer paper guiding function, it is possible to reduce the cost of the transfer paper guide member and eliminate unnecessary consumption of the protective cover kit and troublesome attachment / detachment operation. it can.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an embodiment of the present invention, FIG. 2 is a schematic cross-sectional view showing an opening mode of the above-mentioned embodiment, FIG. 3 is a perspective view of a protective cover kit in the above-mentioned embodiment, and FIG. FIG. 5 is a side view showing the protective cover kit in an open state, FIG. 5 is a schematic sectional view of another embodiment of the present invention, and FIG. 6 is a side view of the protective cover kit in the other embodiment. 1 ... Photosensitive drum, 5 ... Transfer charger, 13 ... Image forming unit, 30 ... Protective cover kit, 30A, 30B ... Protective cover, 30a, 30b ... Guide surface.

Continuation of front page (56) Reference JP-A-1-179952 (JP, A) JP-A-1-267662 (JP, A) JP-A-1-152470 (JP, A) JP-A-59-195250 (JP , A) JP 3-7960 (JP, A) JP 2-272464 (JP, A) JP 60-185966 (JP, A) JP 60-114871 (JP, A) JP 59-195250 (JP, A) JP 59-58447 (JP, A) JP 57-21181 18 (JP, A) Actually opened 62-99065 (JP, U) Actually opened 61-49359 (JP, U) Actually open 57-123238 (JP, U) Actually open 1-90046 (JP, U) Actually open 2-98370 (JP, U) Special public open 6-93142 (JP, B2)

Claims (2)

(57) [Scope of utility model registration request] 1. An image forming apparatus configured such that an image forming unit surrounding the image bearing member is detached from the image bearing member and then attached to and detached from the apparatus main body. A pair of substantially symmetrical protective covers that cover the image carrier so as to surround each half of the image carrier except a transfer portion facing each other. Each protective cover has a closed position that surrounds the image carrier and a double-opened shape. One end is supported by a supporting member of the image carrier so as to be rotatable between an open position where the image carrier is exposed to the outside and an open position where the image carrier is exposed. A guide surface of the transfer paper that is opened and closed in association with the attachment / detachment operation of the unit and the image carrier and is conveyed toward the transfer site on a part of one of the protective covers when the protective covers occupy the open position. An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein a transfer charger is provided on a support member of the protective cover.