JP2584527Y2 - Electrophotographic copier drive - 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 driving device for an electrophotographic copying machine, and more particularly, to fixing a photosensitive drum to a photosensitive drum shaft and preventing movement of the photosensitive drum shaft in the axial direction. The mechanism to do.

[0002]

2. Description of the Related Art Conventionally, techniques for fixing a photosensitive drum and a drum shaft, or preventing axial movement between the drum shaft and a frame supporting the drum shaft, include:
The structure described in JP-A-63-256970 is known. As shown in FIG. 5, a leaf spring 32 is provided between the photosensitive drum shaft 30 and the photosensitive drum 31, and the photosensitive drum shaft 30 and the This prevents the photosensitive drum 31 from moving in the axial direction. In FIG. 5, the photosensitive drum shaft 30 and the drum shaft portion 33 are fixed to the inner rings of the bearings 35 and 34, respectively, and the movement in the axial direction is restricted. An abutment member 36 fixed to the photosensitive drum shaft 30 abuts against the leaf spring 32, and the axial movement of the photosensitive drum 31 that can freely rotate with respect to the photosensitive drum shaft 30 is controlled by the spring of the leaf spring 32. Regulated by force. In the figure, 5 is a rear frame, 37 is a drive plate, and 38 is a front frame.

FIG. 6 shows a general structure for preventing the photosensitive drum from moving in the axial direction. 6, a bearing 41 and a pair of screw cylinders 42 are provided between the C-shaped retaining ring 40 and the rear frame 5 at an intermediate portion of the photosensitive drum shaft 39, and the screw cylinder 42 is adjusted. Thus, the axial movement of the photosensitive drum 43 is prevented. In the drawings, 44 and 45 are bearings with retaining rings, 46 is a front frame, and 47 is a C-shaped retaining ring.

[0004]

However, the above-mentioned conventional structure has the following problems.

First, in the structure shown in FIG. 5, the photosensitive drum shaft 30 and the photosensitive drum 31 move in the axial direction due to the vibration of the leaf spring 32 and the thrust force generated when the photosensitive drum shaft 30 rotates. However, the photosensitive drum 31 vibrates with this, which has an adverse effect on the formation of a latent image on the surface of the photosensitive drum 31. Therefore, there is a disadvantage that a clear image cannot be obtained. If the drum 31 is to be fixed securely, the spring force of the leaf spring 32 increases, and the strength between the parts increases, which causes a problem that the assembling work becomes difficult.

In the structure shown in FIG. 6, a bearing 41 and a C-shaped snap ring 47 are provided in addition to the pair of screw cylinders 42.
However, there is a problem that the number of components is increased and the size cannot be reduced.

The present invention solves the above-mentioned problems, reduces the number of parts, facilitates assembly, and reduces the size of the photosensitive drum. It is intended to prevent axial movement of the shaft.

[0008]

In order to achieve the above object, the present invention provides a photosensitive drum shaft rotatably supported between a pair of support plates via a bearing, and a photosensitive drum shaft with respect to the photosensitive drum shaft. A photoreceptor drum detachably mounted
It is fixed to the photosensitive drum shaft, and engages from the inside with a notch formed on the inside of the photosensitive drum in the axial direction,
A photosensitive drum fixing pin for regulating movement of the photosensitive drum shaft and the photosensitive drum in a rotation direction; a male screw portion formed on an outer side of the photosensitive drum in the axial direction; and one end of the male screw portion screwed with the male screw portion. A female screw cylinder contacting one of the bearings, and a stopper member fixed to the photosensitive drum shaft and contacting the other of the bearings.

[0009]

According to the present invention, the female screw cylinder is pressed against one of the bearings by rotating the female screw cylinder interposed between the photosensitive drum and one of the bearings, and the reaction force applied to the male screw portion. Is applied to the other bearing via a photosensitive drum, a photosensitive drum fixing pin, a photosensitive drum shaft, and a stopper. Thus, the fixing of the photosensitive drum to the photosensitive drum shaft and the regulation of the movement of the photosensitive drum shaft in the axial direction are simultaneously performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The features of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view of a main part showing an embodiment of the present invention. In the figure, a front bearing support plate 2 is detachably attached to a front frame 1 with screws 3. A bearing 4 with a retaining ring is press-fitted and fixed to the front bearing support plate 2 from the inside of the frame, and a bearing 6 with a retaining ring is press-fitted and fixed to the rear frame 5 from the inside of the frame. And these bearings with retaining rings 4, 6
Thus, the photosensitive drum shaft 7 is rotatably supported. The photosensitive drum shaft 7 is driven to rotate from the rear frame 5 by a drive source (not shown) such as a motor. A C-shaped retaining ring 8 is provided on the rear frame 5 side of the photosensitive drum shaft 7 so as to prevent the movement of the photosensitive drum shaft 7 in the direction A.

FIG. 2 shows details of the periphery of the bearing 6 with a retaining ring. The bearing 6 is, for example, a so-called ball bearing type, and has a configuration in which an inner ring 6b and an outer ring 6c are arranged with a large number of balls 6a arranged in a ring therebetween. The C-shaped retaining ring 8 fixed to the photosensitive drum shaft 7 contacts the inner ring 6b of the bearing 6, and the annular stopper 9 fixed to the outer ring 6c of the bearing 6 contacts the rear frame 5. The bearing 4 has the same structure as the bearing 6.

In FIG. 1, a photosensitive drum fixing pin 10 is press-fitted and fixed to an intermediate portion of the photosensitive drum shaft 7. On the other hand, as shown in FIG. 3, a cut portion 16 is formed in the abutting portion 12 protruding inside the photoconductor drum 11 in a radial direction, and the photoconductor drum fixing pin 10 is formed in the cut portion 16. The pin 10 is engaged, and the pin 10 contacts the bottom of the cutout 16. Therefore, the photosensitive drum shaft 7 and the photosensitive drum 11 are fixed in the rotation direction, and the movement of the photosensitive drum shaft 7 in the axial direction is restricted.

On the front frame 1 side of the photosensitive drum 11, a male screw portion 13 is protrudingly provided.
A female threaded cylinder 14 screwed to 3 is interposed between the photosensitive drum 11 and the front bearing support plate 2.
4, the rear frame 5 side of the photoconductor drum 11 is supported by the photoconductor drum shaft 7 via four support protrusions 15, as shown in FIG.

In the above-described structure, when the photosensitive drum 11 is mounted, first, the front bearing support plate 2 is removed, and the photosensitive drum 11 is removed.
Is fitted into the photosensitive drum shaft 7 so that the notch 16 of the butting portion 12 and the photosensitive drum fixing pin 10 are engaged. At this time, the fixing pin 10 fixed to the photosensitive drum shaft 7 passes through the space between the support protrusions 15 on the rear frame 5 side of the photosensitive drum 11, so that the photosensitive drum 11 is moved to the photosensitive drum shaft 7. There is no hindrance to the work of fitting into the. The female screw cylinder 14 may be screwed into the male screw portion 13 of the photosensitive drum 11 in advance, or may be screwed later.

Next, with the bearing 4 fitted on the photosensitive drum shaft 7, the front bearing support plate 2 is fixed to the front frame 1 with screws 3.

Next, when the female threaded cylinder 14 is rotated so as to extend in the axial direction, the female threaded cylinder 14 acts to push the inner ring of the bearing 4 with the retaining ring from the inside of the front bearing support plate 2, and as a reaction, the photosensitive element is exposed. Body drum 11
The abutting portion 12 in the inside of the hollow works to push the photosensitive drum fixing pin 10 in the direction of the rear frame 5. The photosensitive drum fixing pin 10 further includes a C-shaped retaining ring 8 via a photosensitive drum shaft 7 and an inner ring 6b of a bearing 6 with a retaining ring.
Works from the inside of the rear frame 5.

Then, by a series of operations as described above, the female screw cylinder 14 is tightened until the gap between the components becomes zero, whereby the shaft between the front frame 1 and the rear frame 5 and the photosensitive drum shaft 7 is formed. The movement in the direction can be restricted, and the photosensitive drum shaft 7 and the photosensitive drum 11 can be fixed at the same time.

When a rotational force is applied to the photosensitive drum shaft 7, the photosensitive drum shaft 7 and the female screw cylinder 14 fixed to the photosensitive drum 11 are rotatably supported by the bearings 4 and 8, so that the photosensitive drum is rotated. The body drum shaft 7 and the photosensitive drum 11 rotate integrally.

[0019]

As described above, in the present invention, the photosensitive drum shaft and the photosensitive drum are prevented from moving in the axial direction while rotating integrally, and the vibration of the photosensitive drum caused by the rotation is also reduced. And the adverse effect on the latent image formation on the photosensitive drum surface is prevented. Further, since a conventional leaf spring or the like is not required, assembly becomes easy. Furthermore, the number of parts is smaller than that of the conventional product, and the tightening mechanism is integrated with the photoconductor drum, so that the size is reduced. And the photosensitive drum can be fixed at the same time.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention.

FIG. 2 is an enlarged detailed view of the rear frame side in one embodiment of the present invention.

FIG. 3 is an axial sectional view of a portion X of FIG. 1;

FIG. 4 is a sectional view taken along line YY of FIG. 1;

FIG. 5 is a diagram of a conventional drum fixing mechanism using a leaf spring.

FIG. 6 is a diagram of a conventional drum fixing mechanism using a screw cylinder.

[Explanation of symbols]

Reference Signs List 1 front frame, 2 front bearing support plate, 3 screws, bearing with retaining ring, 5 rear frame, 6 bearing with retaining ring, 6a ball, 6b
Inner ring, 6c outer ring, 7 photosensitive drum shaft, 8 C-shaped retaining ring, 9 stopper, 10 photosensitive drum fixing pin, 11
Photoreceptor drum, 12 abutting part, 13 male screw part,
14 Female threaded cylinder, 15 Support projection, 16 Notch, 30 Photoconductor drum shaft, 31 Photoconductor drum, 32
Leaf spring, 33 drum shaft part, 34, 35 bearing, 36 butting body, 37 drive plate, 38 front frame, 39 photosensitive drum shaft, 40 C-shaped snap ring,
41 bearing, 42 screw cylinder, 43 photoreceptor drum, 44, 45 bearing with retaining ring, 46 front frame, 47 C retaining ring

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobunori Sato 2274 Hongo, Ebina, Ebina-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Minoru Kasama 2274, Hongo, Ebina-shi, Kanagawa Fuji Xerox Corporation Institution (72) Inventor Masato Kobayashi 2274 Hongo, Ebina-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd.Ebina Corporation (72) Inventor Hiroshi Kato 2274 Hongo, Ebina-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. Takashi Hoshino 2274 Hongo, Ebina-city, Ebina-shi, Kanagawa Prefecture (72) Inside the Ebina Office of Ebina Co., Ltd. 2274 Hongo Fuji Xerox Corporation Ebina Works (56) References JP-A-63-8654 (JP, A) JP-A-2-304459 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16C 13/02 G03G 21/00 350

Claims (1)

(57) [Scope of request for utility model registration] A photosensitive drum shaft rotatably supported between a pair of support plates via a bearing; a photosensitive drum detachably attached to the photosensitive drum shaft; and the photosensitive drum. Affixed to a shaft, engaged from the inside with a notch formed on the inside in the axial direction of the photosensitive drum,
A photoreceptor drum fixing pin for restricting movement of the photoreceptor drum shaft and the photoreceptor drum in a rotational direction; a male screw portion formed on an outer side in the axial direction of the photoreceptor drum; A drive device for an electrophotographic copying machine, comprising: a female threaded cylinder abutting on one of the bearings; and a stopper member fixed to the photosensitive drum shaft and abutting on the other of the bearings.