JPS6242501B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image bearing member for holding an electrostatic or toner image.

Electrostatic or toner images are formed by various processes. Image holding members on which electrostatic images or toner images are formed include image holding members that have a photoconductive layer and those that do not have a photoconductive layer, which are called electrophotographic photoreceptors.

An image-bearing member usually consists of a support and an image-bearing layer thereon.

Electrophotographic photoreceptors have various configurations in order to obtain predetermined characteristics or depending on the type of electrophotographic process to which they are applied. Typical electrophotographic photoreceptors include a photoreceptor in which a photoconductive layer is formed as an image-retaining layer on a support, and a photoreceptor in which a photoconductive layer is laminated as an image-retaining layer and an insulating layer thereon. is widely used. A photoreceptor composed of a support and a photoconductive layer is used for image formation by the most common electrophotographic processes, ie, charging, image exposure, development, and, if necessary, transfer. For photoreceptors equipped with an insulating layer, this insulating layer can be used to protect the photoconductive layer, improve the mechanical strength of the photoreceptor, improve dark decay characteristics, or be applied to certain electrophotographic processes. There are things set up for this purpose. Typical examples of electrophotographic processes using such a photoreceptor having an insulating layer or a photoreceptor having an insulating layer include, for example, U.S. Pat. 15446 Publication, Special Publication No. 46-3713, Publication No. 23910-1972, Publication No. 24748-1974,
It is described in Japanese Patent Publication No. 42-19747, Japanese Patent Publication No. 4121-1974, etc.

A predetermined electrophotographic process is applied to the electrophotographic photoreceptor to form an electrostatic image, and this electrostatic image is developed and visualized.

A typical structure of an image holding member without a photoconductive layer is one having an insulating layer as an image holding layer,
Some typical uses of this image holding member will now be described.

(1) For example, Japanese Patent Publication No. 32-7115, Japanese Patent Publication No. 32-7115,
As described in Japanese Patent Publication No. 8204 and Japanese Patent Publication No. 43-1559, electrostatic images formed on electrophotographic photoreceptors without a photoconductive layer are used for the purpose of improving the repeatability of electrophotographic photoreceptors. The toner image is transferred to an image holding member and developed, and then the toner image is transferred to a recording medium.
An image holding member used in this electrophotographic process.
(2) In addition, as another electrophotographic process in which an electrostatic image is formed on an image holding member without a photoconductive layer in correspondence with an electrostatic image formed on an electrophotographic photoreceptor, for example, Japanese Patent Publication No. 45-30320 As described in Japanese Patent Publication No. 48-5063, Japanese Patent Application Laid-Open No. 51-341, etc., a screen-shaped electrophotographic photoreceptor having many minute openings is coated with a predetermined electrophotographic process. By applying corona charging to an image holding member that does not have a photoconductive layer through this electrostatic image, the ion flow of the corona is modulated to form an electrostatic image that does not have a photoconductive layer. An example of this process is to form a final image on a non-containing image holding member, develop it with toner, and transfer it to a recording medium. An image holding member used in this electrophotographic process. (3)
In addition, according to other electrophotographic processes, a toner image formed on an electrophotographic photoreceptor or an image holding member without a photoconductive layer is not directly transferred to a recording medium, and an image holding member without another photoconductive layer is used. The toner image is then transferred from the image holding member to a recording medium and fixed. An image holding member used in this electrophotographic process. This process is particularly useful for forming color images or for high speed copying.
Recording media are usually highly flexible, such as paper or film, and for this reason, it is possible to transfer a three-color image onto a recording media while accurately aligning it, with almost no deformation. A more accurately aligned color image is formed by transferring a three-color image to an image holding member that can be formed from a suitable material and then transferring it to a recording medium at once. Furthermore, it is effective for speeding up copying that the toner image is transferred to the recording medium via the image holding member. (4) In addition, as another process, an electric signal is applied to a multi-needle electrode to form an electrostatic image in accordance with the electric signal on the surface of an image holding member that does not have a photoconductive layer, and this is developed to form an image. It is something that can be done. There are image holding members used in this electrophotographic process.

Image holding members used in electrophotography are easily damaged because they are subjected to various electrical and mechanical shocks during corona charging treatment, development treatment, cleaning treatment, and the like. Once the image holding member is damaged, the quality of the image formed will be significantly reduced. Therefore,
An image holding member whose performance has deteriorated is removed and replaced. Therefore, the image holding member is required to be a consumable item and to be easy to manufacture and low in cost. Incidentally, the element that has conventionally been the most problematic in terms of manufacturing and cost in image holding members is the support. Generally, a metal drum is often used as this support. Many metal drums have been used in which molten metal is poured into a mold having an annular opening, and the metal is cooled while passing through the annular opening. This is done by so-called extrusion molding.
However, since the metal drum formed in this way does not have a bottom, in order to attach it to the main body of a copying device as an image holding member, a flange as a joining member for that purpose must be separately formed and integrated with the metal drum. It required many work steps to manufacture the product.

Further, the image holding member must be mounted on the main body of the copying device and rotated with high precision without causing eccentricity. For this reason, high accuracy is required for all of the circumferential surface accuracy of the flange, the end surface accuracy of the metal drum, and the joining accuracy between the metal drum and the flange, and it is not easy to join the flange without eccentricity.

Furthermore, a metal drum without a bottom is easily deformed by external forces, so it is necessary to increase the wall thickness to supplement the strength and to join the flanges, and as a result, it is difficult to reduce the weight of the metal drum. It was hot.

SUMMARY OF THE INVENTION The main object of the present invention is to provide an image holding member having a metal drum that does not require a flange to be attached to at least one of both ends of the metal drum.

Another object of the present invention is to provide an image holding member with high rotational accuracy.

Another object of the present invention is to provide an image holding member having a metal drum that is thin but has high mechanical strength.

Another object of the present invention is to provide an image holding member having a metal drum integrally processed for driving the image holding member.

In the image holding member according to the present invention, the support body is composed of a metal drum, one end surface of the metal drum is continuous and integrated with the peripheral surface of the metal drum, and the integrated end surface has a main body of the copying machine. It is characterized in that a driving processed portion having a concave portion or a convex portion for transmitting rotational force from the side to the image holding member is formed, and a flange is attached to the other end surface.

That is, since the metal drum used in the image holding member of the present invention has a bottom portion that is continuous and integrated with the side surface, there is no need to separately join the flange.
In addition, since the bottom of the metal drum is continuous and integrated with the side surface, the center of the bottom and the rotation axis of the metal drum are aligned, making it possible to easily determine the rotation axis without causing eccentricity. It is possible to easily ensure high turning accuracy when the vehicle is rotated. Also,
The metal drum has a highly reinforced structure with a continuously formed bottom, so even if the thickness of the metal drum is made thin, external forces such as rotational force and cleaning sliding of the image holding member can be avoided. It is not easily deformed, is suitable for maintaining perfect circularity, and enables a lightweight image holding member.

In addition, as will be described later, a driving processing portion having a concave or convex portion for transmitting the rotational force of the metal drum is formed on the end face of the metal drum, so that the attachment mechanism of the image holding member to the main body of the copying machine is improved. It can be simplified.

Such a metal drum used in the present invention can be formed by drawing a metal material.

Forming a metal drum by drawing a metal material involves pressing a metal plate into a mold under pressure and forming it into a drum, so metals formed by using a smooth metal plate. The surface smoothness of the drum is good, and there is no need for polishing as a secondary process. In addition, since secondary processing is not required, a metal drum with the strength required as an image holding member can be formed without requiring mechanical strength for secondary processing, and as a result, a metal drum with a thin wall thickness can be formed. It is also possible to manufacture a lightweight image holding member. As described above, by using the metal drum formed by the drawing process, it is possible to manufacture an image holding member that is easy to manufacture, low in cost, and lightweight. Furthermore, since the metal plate used for forming forms the bottom of one end of the metal drum that is formed by processing, the bottom is processed for driving the image holding member. By carrying out this process, it is possible to manufacture an image holding member that can be attached to a copying machine extremely easily. In addition, the metal drum can be used as a paint for forming an image-retaining layer.
For example, when forming an image-retaining layer as a film by dipping it into a paint containing dispersed photoconductive particles and pulling it up, the paint can be immersed with the bottom side facing down. This is very advantageous in terms of manufacturing, as it does not get inside the metal drum and contaminate the inner wall of the metal drum.

Next, the effect of applying driving processing to the bottom of the metal drum will be explained with reference to the drawings.

FIG. 1 shows a typical configuration of a conventional image holding member. An image holding layer 2 is formed on a metal drum 1. Since both bottom surfaces of the metal drum are completely open, flanges 3 and 4 are provided for attachment to the main body of the copying device.
This flange has undergone the necessary processing to drive the image holding member, and is made up of screws 5 and nuts 6.
The ends a and a' of the metal drum are pressed and fastened together. This flange is formed of a metal plate to provide electrical continuity between the metal drum and the copying device. As described above, the conventional image holding member requires separately formed flanges to be fixed to both sides of the metal drum, requires many manufacturing steps, and has a complicated structure.

FIG. 2 shows a typical embodiment of the image holding member of the present invention, in which one end surface 11 of a metal drum 7 formed by a drawing process is processed for driving the image holding member. A flange 13 is attached to the other end face. This end face 11 is adapted to mesh with a hook 9 of a connecting gear 8 attached to the main body 10, and the rotational force of the connecting gear is transmitted to the image holding member through a driving processed portion of the end face 11.

FIG. 3 shows the shape of the end surface 11 of the metal drum 7, in which a recess 12 is formed corresponding to the hook 9 of the connecting gear 8.

FIG. 4 is a perspective view of the connecting gear 8, in which a hook 9 is formed. Since the end face 11 constitutes a part of the metal drum, by performing driving processing using this end face, there is no need to fasten a separately molded flange. In addition, such drive processing of the end face can be formed in a separate process from the drawing process of the metal drum, but it can also be formed in the same way as the drawing process, and can be processed almost instantly. can. In particular, this driving process is easier when forming uneven portions as shown in FIG. 3.

Further, since the end face 11 is integrated with the metal drum, even if the end face is very thin, the material strength is excellent, so that a lightweight image holding member can be formed. In addition to the case shown in FIG. 2, the drive processing portion formed on the end face may have any other shape. Various metals are appropriately used to form the metal drum, such as aluminum, iron, and steel.

The thickness of the metal drum is usually preferably about 0.1 to 3 mm, particularly about 0.2 to 1.5 mm. Further, the surface smoothness of the metal drum is preferably 0.1 s to 10 s, particularly 1 s to 3 s.

As explained above, in the image holding member according to the present invention, the metal drum, which has conventionally been the largest element in terms of manufacturing and cost, can be manufactured extremely easily, and the cost can also be significantly reduced. is,
Furthermore, it is possible to achieve a significant weight reduction of the image holding member. Therefore, the restriction of collecting and recycling used image holding members is eliminated, and a so-called disposable and service-free image holding member can be provided.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of a conventional image holding member.
FIG. 2 is a diagram showing one embodiment of the image holding member according to the present invention. FIG. 3 is a diagram showing the shape of the end face of the metal drum shown in FIG. 2. FIG. 4 is a diagram showing the connecting gear shown in FIG. 2. 2... Image holding layer, 7... Metal drum, 8... Connection gear, 9... Hook, 10... Main body, 11...
End face, 12... recess, 13... flange.

Claims (1)

[Claims] 1. In an image holding member having an image holding layer on a support that holds an electrostatic image or a toner image, the support consists of a metal drum, and one end surface of the metal drum is continuous and integral with the peripheral surface of the metal drum. A driving processed portion having a concave or convex portion for transmitting the rotational force from the copying device main body to the image holding member is formed on the integrated end surface, and the other end surface An image holding member characterized in that a flange is attached to the flange.