JP3467458B2 - Photoreceptor drum holding structure and image forming apparatus having the structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive drum holding structure for rotatably holding both ends of a photosensitive drum and an image forming apparatus having the structure.

[0002]

2. Description of the Related Art Conventionally, a photosensitive drum used in an image forming apparatus is removed from the image forming apparatus at the time of replacement and is replaced with a new photosensitive drum. Since the photoconductor drum has a photoconductor layer on its outer peripheral surface, when a new photoconductor drum is mounted, it must be mounted by holding both ends thereof. For example, Japanese Industrial Standard (JIS) A
In an image forming apparatus capable of forming an image on a wide sheet such as a size of row 0 (hereinafter referred to as "A0"), the photosensitive drum is about 1 m long, so the photosensitive drum is slid in the length direction. It is difficult to mount it on the device. Therefore, in this type of image forming apparatus, it is necessary to mount the photosensitive drum from the front side of the apparatus while holding both ends of the photosensitive drum.

When an opening / closing cover that can be pulled out to the front is provided above the front side of the housing so that the photosensitive drum can be replaced from the front side of the apparatus, it is difficult to reach the mounting position due to the front side of the opening / closing cover. . Moreover, since the optical system is provided above the photoconductor drum, the photoconductor drum cannot be mounted from directly above. Therefore, in the conventional wide image forming apparatus, the rail provided at a predetermined position in the housing is removed, the rail is fixed to the side wall of the housing, and the photosensitive drum is rolled from the front side to the rear side along the rail. I was wearing it.

[0004]

However, when mounting the photosensitive drum, the rail is removed from a predetermined position in the housing and fixed to the side wall of the housing, and after the mounting is completed, the rail is removed from the side wall of the housing. It has to be mounted again at a predetermined position in the housing, which is troublesome. Further, there is a problem that the number of parts is increased by adopting the rail.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photoconductor drum holding structure which allows a photoconductor drum to be easily mounted with a simple structure, and an image forming apparatus having the structure.

[0006]

In order to achieve the above object, the invention according to claim 1 is a cylindrical body having a predetermined length, and a photosensitive drum having a photosensitive layer on its outer peripheral surface. Is a photosensitive drum holding structure for rotatably holding both ends of the photosensitive drum, and has a pair of holding members respectively formed corresponding to both ends of the photosensitive drum. A fixed-side receiving member that has a receiving surface that is recessed in a substantially semi-circular shape, and is fixed and fixed to a predetermined portion of the image forming apparatus And a rotating side receiving member that rotates between an open position and a closed position with a support shaft provided at one end as a fulcrum, and when the rotating side receiving member is in the closed position,
The rotating-side receiving member and the fixed-side receiving member face each other, and a circular receiving surface that rotatably holds the end of the photosensitive drum is formed by the receiving surfaces of the rotating-side receiving member and the fixed-side receiving member. Is in the open position, the receiving surface of the rotating side receiving member faces upward so that the end portion of the photosensitive drum can be placed on the receiving surface.
With the end of the photoconductor drum on the receiving surface of the
When the rotating side receiving member is rotated to the closed position side, the photosensitive member is exposed.
The body drum is separated from the rotating side receiving member, and the fixed side receiving member is
Special feature is that it is designed to roll over to
This is a characteristic structure for holding the photosensitive drum.

According to this structure, the end of the photosensitive drum is placed on the receiving surface of the rotating side receiving member at the open position, and the rotating side receiving member is rotated to fix the photosensitive drum to the fixed side. It can be moved to the receiving member, and at the closed position, the receiving surfaces of the rotating-side receiving member and the fixed-side receiving member can surround and rotatably hold the end portion of the photosensitive drum. Therefore, the photosensitive drum can be easily mounted with a simple structure. The invention according to claim 2 is
An operation for gripping the turning side receiving member at the end opposite to the end where the support shaft is provided when the turning side receiving member is turned between the open position and the closed position. And a screw hole for fixing the rotating-side receiving member and the fixed-side receiving member when the rotating-side receiving member is in the closed position. The photoconductor drum holding mechanism according to claim 1.

According to this structure, the turning side receiving member can be turned easily and surely by grasping the operation portion. Further, the rotating side receiving member and the fixed side receiving member can be easily fixed with screws. Further, claim 3
3. The photosensitive drum according to claim 1, wherein the rotating side receiving member is regulated by a stopper so that the receiving surface faces upward in the open position. It is a holding mechanism.

According to this structure, the receiving surface of the rotating side receiving member can be surely directed upward at the open position, so that the photosensitive drum can be easily placed on the receiving surface. Further, since the stopper supports the rotating side receiving member, the strength of the receiving surface of the rotating side receiving member supporting the photosensitive drum can be increased. Claim 4
Of the invention, the fixed-side receiving member is inclined with respect to the horizontal direction.
It is mounted for the purpose of claim 1.
The photoconductor drum holding mechanism according to any one of item 1 to 3 above.
According to this configuration, the photosensitive drum is
Suppresses shock when rolling and moving to the fixed side receiving member
You can Further, according to the invention of claim 5 , an image can be formed on a wide sheet, and the photosensitive drum can be exchanged from the front upper side of the front side by opening the opening / closing cover on the front side upper side of the housing. An image forming apparatus comprising the photosensitive drum holding structure according to any one of claims 1 to 4 , wherein when a new photosensitive drum is attached after removing the photosensitive drum,
An image characterized in that the photoconductor drum can be mounted by placing the turning side receiving member in the open position, placing both ends of the photoconductor drum on the receiving surface, and then turning to the closed position. It is a forming device.

According to this structure, it is possible to provide an image forming apparatus having a photosensitive drum holding structure that achieves the above effects.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an internal configuration of an image forming apparatus 1 according to an embodiment of the present invention. The image forming apparatus 1 is, for example, A0.
An image forming apparatus 1 capable of forming an image on a wide sheet of size or the like, including a sheet accommodating section 2 for accommodating a roll sheet or a cut sheet, and a conveyance for feeding a sheet to an image forming mechanism. Mechanism 3, an optical system 4 for reading an original, an image forming mechanism 5 for forming an image based on light provided from the optical system and transferring the image onto a sheet, and for fixing the image transferred on the sheet. The fixing device 6 of FIG.

The image forming mechanism 5 includes a photosensitive drum 7, a main charger 8 for charging the photosensitive drum 7,
A developing device 9 for developing the electrostatic latent image formed on the photosensitive drum 7 into a toner image, a cleaning device 10 for cleaning the residual toner on the surface of the photosensitive drum, and the like are provided. FIG. 2 is a schematic perspective view showing a mounting mode of the photosensitive drum 7. Housing 1 of image forming apparatus 1
A part of the upper front side of 1 forms an opening / closing cover 12 that can be opened / closed by sliding in the front-rear direction, for example.
FIG. 2 shows a state in which the open / close cover 12 is open.

At the time of replacement, the photosensitive drum 7 is removed from the space formed by opening the opening / closing cover 12 to the outside of the housing 11 and replaced with a new photosensitive drum 7. When mounting a new photoconductor drum 7, in a wide image forming apparatus 1 such as this image forming apparatus 1, the photoconductor drum 7 is as long as about 1 m. Therefore, slide the photoconductor drum in the length direction. Difficult to attach to the device. Therefore, the photoconductor drum 7 is mounted from both sides of the front side as shown by the arrow in FIG.

FIG. 3 is a schematic perspective view showing a holding structure for the photosensitive drum 7. Further, FIG. 4 shows an arrow A- shown in FIG.
It is a principal part sectional view seen along A. FIG. However, since the configuration and mounting structure of the photosensitive drum 7 are the same at both ends, only the vicinity of one end will be described below. 3 and 4
Referring to, the photosensitive drum 7 has, for example, a cylindrical shape,
A flange portion 13 that is cylindrical and is coaxial with the photosensitive drum 7 projects at one end thereof. From one end of the flange portion 13,
A convex portion 14 having a cylindrical shape and coaxial with the photosensitive drum 7 further projects. The outer peripheral surface of the convex portion 14 has a cylindrical bearing 1.
It is rotatably fitted into the inner peripheral surface of the member 5. Convex portion 14
A connecting groove 16 for connecting to a rotary shaft (not shown) of a drive system provided in the image forming apparatus 1 is formed at one end of the.

The photosensitive drum 7 is rotatably held by a holding member 18 attached to one side surface 17a of a mounting plate 17 fixed in the housing 11. Holding member 18
Is a fixed side receiving member 19 having a substantially semi-circular cross section attached and fixed to the side surface 17a of the mounting plate 17, and a support shaft having a shape corresponding to the fixed side receiving member 19 and provided at one end 20a. It comprises a turning side receiving member 20 rotatably mounted between a closed position and an open position with 21 as a fulcrum. One end of the support shaft 19 has one side surface 17a of the mounting plate 17.
Are linked to. A flange receiving member 22 for receiving the flange portion 13 is formed on the outer peripheral surface of the rotating side receiving member 20.

The inner peripheral surfaces of the fixed-side receiving member 19 and the rotating-side receiving member 20 form receiving surfaces 23 and 24 for receiving the bearing 15, respectively.
Is in the closed position, the rotating side receiving member 20 and the fixed side receiving member 19 face each other, and the receiving surfaces 23 and 24 of each other form a circular receiving surface corresponding to the outer peripheral surface of the bearing 15. . When mounting the photoconductor drum 7, first see FIG.
As shown by, the bearing 15 and the flange portion 13 are placed on the receiving surface 24 of the rotating side receiving member 20 and the upper surface of the flange receiving member 22, respectively, with the rotating side receiving member 20 in the open position. . One side 17 of the mounting plate 17
One side of, for example, a plate-shaped stopper 25 for receiving the rotating side receiving member 20 at the open position is connected to a. The stopper 25 is a receiving surface 24 of the turning side receiving member 20.
The upper surface of the flange receiving member 22 receives the outer peripheral surface of the flange receiving member 22 so as to face upward in the open position.

At the other end 20b of the turning side receiving member 20, an operating portion 26 for holding the turning side receiving member 20 when turning the turning side receiving member 20 between an open position and a closed position is formed. As the rotating side receiving member 20 is gripped by the operating portion 26 and rotated from the open position to the closed position, the photosensitive drum 7 moves from the rotating side receiving member 20 to the fixed side receiving member 19. Will be moved. For example, a screw hole 27 is formed in the operation portion 26, and a screw hole 28 is formed in one end of the fixed side receiving member 19 facing each other at the closed position. When the turning side receiving member 20 reaches the closed position, these screw holes 27, 2
A screw (not shown) is fastened through 8, and the bearing 15 is fixed by the rotating side receiving member 20 and the fixed side receiving member 19, and the photosensitive drum 7 is rotatably held.

Further, in order to prevent an impact from occurring when the photosensitive drum 7 is moved to the fixed side receiving member 19 by rotating the rotating side receiving member 20, the fixed side receiving member 19 is The receiving surface 23 is attached so as to be oblique to the upper side. FIG. 5 is a schematic diagram showing the procedure for attaching the photoconductor drum 7, and shows how the photoconductor drum 7 is attached in stages. When the photoconductor drum 7 is mounted, the photoconductor drum 7 is first received from the front side (the right side shown in FIG. 5) as shown in FIG. 24. And
By lifting the turning side receiving member 20 in the closing direction B, the photosensitive drum 7 is lifted together with the turning side receiving member 20.

As shown in FIG. 5B, when the turning side receiving member 20 is in the upright state, the photosensitive drum 7 moves away from the turning side receiving member 20 and rolls to the fixed side receiving member 19. To do. Since the fixed side receiving member 19 is obliquely attached, it is possible to suppress the impact when the photosensitive drum 7 moves from the rotating side receiving member 20 to the fixed side receiving member 19. When the turning side receiving member 20 is further rotated in the closing direction B and reaches the closing position as shown in FIG. 5B, the turning side receiving member 20 and the fixed side receiving member 19 are screwed through the screw holes 27 and 28. 29 is fastened. The rotating side receiving member 20 and the fixed side receiving member 19 are connected, the mounting of the photosensitive drum 7 is completed, and the photosensitive drum 7 is rotatably held.

The present invention is not limited to the contents of the above embodiment, and various modifications can be made within the scope of the claims. For example, the fixed side receiving member 19 and the rotary side receiving member 20 are not limited to being connected by the screw 29, but may be connected by another connecting mechanism.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an internal configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a mounting mode of a photosensitive drum.

FIG. 3 is a schematic perspective view showing a holding structure for a photosensitive drum.

FIG. 4 is a cross-sectional view of main parts as seen along an arrow AA shown in FIG.

FIG. 5 is a schematic diagram showing a procedure for mounting a photosensitive drum.

[Explanation of symbols]

1 Image forming device 7 Photosensitive drum 11 housing 12 Open / close cover 18 Holding member 19 Fixed side receiving member 20 Rotating side receiving member 20a one end 20b the other end 21 spindle 23 Receiving surface 24 Receiving surface 25 stopper 26 Operation part 27 screw holes

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G03G 21/16 G03G 21/00 350 G03G 15/00 550 F16C 13/00

Claims (5)

(57) [Claims] 1. A photoconductor drum holding structure for rotatably holding both ends of a photoconductor drum having a photoconductor layer on the outer peripheral surface of a tubular body having a predetermined length. There is a pair of holding members formed respectively corresponding to both ends of the drum, and each holding member has a receiving surface that is recessed in a substantially semi-arc shape.
A fixed side receiving member attached and fixed to a predetermined portion of the image forming apparatus and a receiving surface recessed in a substantially semi-arcuate shape, and a spindle provided at one end which is paired with the fixed side receiving member. A pivot side receiving member that pivots between an open position and a closed position as a fulcrum is included, and when the pivot side receiving member is in the closed position, the pivot side receiving member and the fixed side receiving member face each other. Then, a circular receiving surface that rotatably holds the end portion of the photosensitive drum is formed by the receiving surfaces of each other, and when the rotating side receiving member is in the open position, the rotating side receiving member Has a receiving surface facing upward, and the end of the photosensitive drum can be placed on the receiving surface. The end of the photosensitive drum is placed on the receiving surface of the rotating side receiving member.
Rotate the rotating side receiving member to the closed position side with it placed.
Then, the photosensitive drum separates from the rotating side receiving member,
It comes to roll to the fixed side receiving member
A photosensitive drum holding structure characterized by being 2. A rotating side receiving member is rotated between an open position and a closed position at an end of the rotating side receiving member opposite to an end where the support shaft is provided. And a screw hole for fixing the rotating side receiving member and the fixed side receiving member when the rotating side receiving member is in the closed position. It is formed, The claim 1 characterized by the above-mentioned.
The photosensitive drum holding mechanism described. 3. The photosensitive drum according to claim 1, wherein the rotating side receiving member is regulated by a stopper so that the receiving surface thereof faces upward at the open position. Retention mechanism. 4. The fixed side receiving member is
It is attached diagonally, characterized in that
4. The photoconductor drum holding mechanism according to any one of item 3. 5. An image forming apparatus capable of forming an image on a wide sheet, and opening and closing an opening cover at the front upper side of the housing to replace the photosensitive drum from the front upper side of the front side. When the photoconductor drum holding structure according to any one of claims 1 to 4 is provided and a new photoconductor drum is attached after the photoconductor drum is removed, the rotating side receiving member is used. An image forming apparatus in which the photosensitive drum can be mounted by placing the both ends of the photosensitive drum on the receiving surface in the open position and then pivoting to the closed position.