JPH059735Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image carrier that can be attached to the main body of an image forming apparatus.

[Prior Art] As a molding method for a small-sized image bearing drum, there is a method in which impact molding is performed to close one bottom of the drum during molding to form a stub-like shape. When using such a photosensitive drum as a photosensitive drum, a part of the bottom of the photosensitive drum can be formed into a shaft shape, and this shaft can be used to provide electrical conduction to the photosensitive drum.

[Problems to be solved by this invention] However, if the diameter of the drum is further reduced,
Impact molding makes it impossible to close off one side of the drum. Furthermore, when establishing electrical continuity between the drum and the main body of the device,
As shown in Publication No. 153367, when the grounding member is pressed against the circumferential surface of the drum or the circumferential surface of the support shaft, the pressing force acts as a braking force to prevent rotation of the drum. Therefore, there is a possibility that the rotation accuracy of the drum may be reduced due to load fluctuations due to this braking force.

Therefore, the present invention provides an image carrier that is compatible with miniaturization and that also enables reliable electrical continuity between the image carrier and the main body of the apparatus without impairing the rotational accuracy of the image carrier. be.

[Configuration for Solving the above-mentioned Problems] The present invention for solving the above-mentioned problems has an image bearing member that can be attached to an image forming apparatus main body, and includes a conductive cylindrical base and an outer surface of the conductive cylindrical base. The provided image bearing layer is provided in contact with the inner surface of the conductive cylindrical base in order to establish conduction with the image forming apparatus main body side when attached to the image forming apparatus main body, and the rotation of the conductive cylindrical base is The image carrier is characterized in that it has a distal end of a conductive member located at the center and electrically connected to the image forming apparatus main body side, and a conductive member that elastically contacts in the thrust direction.

[Examples] The examples described below relate to photosensitive drums and insulating drums used in electrophotographic copying machines and electronic recording devices, and more specifically, to image-bearing drums that form latent images and toner images on their surfaces. Concerning the conduction mechanism. More specifically, the embodiments described below include:
A conduction mechanism for an image bearing drum that carries a latent image, and an image bearing layer that holds charge and toner on the surface;
A metal drum that serves as a support for the image bearing layer, an insulating flange provided at the end of the metal drum, and an inner circumferential surface of the metal drum are engaged and supported, and when the metal drum is loaded into the apparatus main body. , and a conductive member that engages with the conductive member on the main body side. Further, the conductive member is a cylindrical plate, with a part thereof cut out in the shape of a leaf spring.

Now, an embodiment to which the present invention is applied will be described with reference to the drawings.

FIG. 1 is a partially sectional perspective view of a photosensitive drum employing the electrical conduction mechanism of the present invention, and FIG. 2 is a sectional view showing the correspondence between the photosensitive drum and a structure on the apparatus main body side. The photosensitive drum used here is the conventional Japanese Patent Application Publication No. 58
The example shown is one installed in a process cartridge as disclosed in Japanese Patent No. 202459.

In the figure, a photosensitive drum 1 is a cylindrical member with openings at both ends, and resin flanges 2 and 3 are attached to both ends. This resin flange 2 engages with the cartridge housing 4 through a housing engaging portion 2a that engages with the housing 4 as a bearing to support the drum 1 on the housing 4, and also has a positioning pin receiving hole 2b.
The cartridge is engaged with a main body positioning pin 6 which is electrically connected to the side plate 5 of the main body of the image forming apparatus, thereby supporting the cartridge in the main body. A resin flange 3 on the other end side of the drum 1 supports the drum 1 on a cartridge housing 4 via a positioning pin 7.

The photosensitive drum 1 has a gear portion 2c provided on the flange 2.
A gear (not shown) on the main body of the device meshes with the gear, and is driven by the rotation of the gear on the main body. Reference numeral 8 in the figure denotes a disc-shaped conduction plate for grounding the drum 1, which is provided inside the flange 2. It is tightly fitted to the inner wall of the drum 1 to establish electrical continuity with the drum 1, and at the same time, the position of the electrically conductive plate itself is fixed. Further, the conductive plate 8 is cut out to form a leaf spring portion 8b. By attaching the cartridge to the cartridge body, the plate spring portion 8b comes into elastic contact in the thrust direction with the tip of the body positioning pin 6 that passes through the opening provided in the flange 2, and the photosensitive drum 1 and the body are connected to each other. The conduction will be established. That is, it has a conductive plate 8 that is provided in contact with the inner surface of the drum 1 and elastically contacts in the thrust direction the tip of a pin 6 located at the center of rotation of the drum 1 and conductive with the main body side. 6 and the conductive plate 8, reliable conduction can be established between the drum 1 and the main body.

[Other Embodiments] As shown in FIG. 3, the mounting structure of the conduction plate 8 is such that the conduction plate 8 is heat caulked and the resin flange 2 is attached to the drum using screws 9 or the like in advance. By fixing it, the positioning of the conductive plate can be ensured.

Moreover, instead of driving the drum 1 from the gear part 2c provided on the resin flange 2, as shown in FIG.
Rotate the positioning pin 6, and this rotating pin 6
The convex portion 10a of the drive transmitter 10 fixed to the resin flange 2 may be engaged with the concave portion 2d of the resin flange 2 to drive this flange.

In the above embodiments, the insulating flange is made of resin, but other materials such as processed paper, ceramic, and processed wood can also be used. Further, as an example of continuity, it is possible to apply not only earth (grounding) but also a voltage of positive or negative polarity. Examples of image bearing drums include not only photoreceptors installed in process cartridges, but also single drums and insulating drums having a surface layer capable of retaining charges.

Note that, as an example of use of the photosensitive drum 1, charging, exposing, developing, transferring, and cleaning means are sequentially arranged around the photosensitive drum 1, but a description of these well-known configurations will be omitted.

(1) Since there is no need to form the image bearing drum body into a bottomed cup shape, it is possible to create a drum with a diameter smaller than the required drum length. Therefore, process cartridges and equipment to which such a drum is applied can be downsized.

(2) Since the flange of the image bearing drum does not need to be made of metal, material costs can be reduced.

[Effects of the invention] As detailed above, the present invention is capable of responding to miniaturization, and also enables reliable electrical conduction between the image bearing member and the main body of the apparatus without impairing the rotational accuracy of the image bearing member. An image carrier can be provided.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a photosensitive drum to which the present invention is applied, Fig. 2 is a sectional view showing the relationship between the drum shown in Fig. 1 and the main body of the device, and Figs. 3 and 4 are perspective views showing other embodiments. It is. 1...Photosensitive drum, 2...Resin flange, 6
. . . Positioning pin, 8 . . . Conductive plate, 8 a .

Claims (1)

[Claims for Utility Model Registration] (1) An image bearing member that can be attached to a main body of an image forming apparatus, comprising: a conductive cylindrical base; an image bearing layer provided on the outer surface of the conductive cylindrical base; and image formation. In order to establish electrical conduction with the image forming apparatus main body side when mounted on the apparatus main body, it is provided in contact with the inner surface of the conductive cylindrical base, is located at the center of rotation of the conductive cylindrical base, and is located on the image forming apparatus main body side. An image carrier comprising: a conductive body that elastically contacts a tip of a conductive member that is electrically connected to the conductive member in a thrust direction; (2) A utility model registration in which a resin flange is provided at the end of the conductive cylindrical base, and the conductive member passes through an opening provided in the resin flange and comes into contact with the tip of the conductive body. An image carrier according to claim (1). (3) A resin flange is provided at an end of the conductive cylindrical base, and the conductor is provided inside the resin flange. Image carrier. (4) The conductive body is a disc-shaped conductive plate, and includes a protrusion that extends outward from the circular arc portion of the disc and contacts the inner surface of the conductive drum as the conductive cylindrical base, and a protrusion as the conductive member. An image carrier according to claim (1) of the utility model registration, comprising: an elastic protrusion that comes into contact with a tip of a central axis of rotation of the image carrier. (5) A resin flange is provided at the end of the conductive cylindrical substrate, and the resin flange is provided with a drive gear for driving a photosensitive drum. The image carrier described in item ). (6) The conductive member is a positioning pin provided on the image forming apparatus main body, and the positioning pin is provided at the end of the conductive cylindrical base when the image carrier is attached to the image forming apparatus main body. Utility model registration claim No. 1 in which the image carrier is positioned with respect to the device main body by passing through the opening of the resin flange.
The image carrier described in (1). (7) The image carrier according to claim 1, wherein the image carrier layer is a photoreceptor layer. (8) The image carrier according to claim 1, wherein the image carrier layer is an insulating layer capable of retaining charge. (9) The image carrier according to claim (1), wherein the image carrier layer holds a toner image. (10) The image carrier is provided in a process cartridge, and when the process cartridge is installed in the image forming apparatus main body, it is installed in the image forming apparatus main body. The image carrier described in item 1). (11) The image carrier according to claim 1, wherein the image forming apparatus is a copying machine, and the image carrier is attachable to the copying machine. (12) The image carrier according to claim 1, wherein the image forming apparatus is a recording device, and the image carrier is attachable to the recording device.