JPS5934584A - Method of fixing photoconductive sleeve into cylindrical body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of attaching a sleeve to an inner cylinder. More specifically, one invention relates to a method for mounting and securing a photoconductor on a drum for use in a copying machine.

BACKGROUND OF THE INVENTION Small-sized copying machines use photoconductor drums whose circumference 1- is shorter than the length of copy paper. There must be no seals or other discontinuities in the photoconductor because the images overlap on the photoconductor. Such discontinuities cause stripes in the finished copy.

However, due to deterioration of photoconductor properties over time, it is necessary to replace the photoconductor surface. If the photoconductor is attached directly to the drum surface, the entire drum must be replaced when the photoconductor surface becomes worn. It is not practical or economical to frequently replace copiers at the customer's location where they are installed.

In addition to the need for the photoconductor to be seamless and continuous in those types in which the photoconductor is attached to a drum, slippage between the attached photoconductor and the drum surface must be avoided. Must not occur. In other words, while it is necessary that the photoconductor be firmly attached to the drum, it is also necessary that the photoconductor be easily replaced at the copier site without the need for special tools. 2- Yes.

The rigid mounting of a sleeve around a circular or cylindrical holder is required in many fields. For example, in the driving wheels of a steam locomotive, an outer rim of forged steel is integrally attached to an inner rim. For this purpose, the inner diameter of the outer rim is made smaller than the outer diameter of the inner rim, and is attached by heat shrinkage. That is, the outer rim is heated and increases in diameter, and the unidirectional rim is cooled and decreases in diameter.

In this state, the outer rim is fitted into the inner rim, the outer rim is cooled, the inner rim is warmed, and the two rims are integrated. However, this method of attachment cannot be used to attach a photoconductor sleeve to a metal drum. The photoconductor is generally coated onto a stable isometric plastic support such as Mylar. Therefore, heating the sleeve will cause it to melt or become distorted. Furthermore, the copier installation light does not allow sufficient cooling of the drum without special tools.

Although mounting carrier sheets under tension in rotary printers has been practiced, this is not a solution for mounting photoconductors in copiers. In this method, the locking portion extends outside the diameter of the drum, so the surface is discontinuous.

This is not a problem with printers. That is, the printing plate extends radially beyond the extension of the loaf portion.

One solution to the problem of attaching the photoconductor is to wrap a sheet 1 - longer than the diameter of the drum around the drum and attach the ends of the sheet to the drum with adhesive or clips. One end of the sheet is attached to the tension section of the drum, which is then swung outward and returned to position so that the sheet is attached under tension. This method also has the disadvantage that surface discontinuities occur at both end portions of the seams.

Other methods have been proposed for attaching one end of a sheet of photoconductor that is slightly longer than the circumference of the Drano. The seams attached at one end are wrapped around the drum and the other ends are overlapped and attached. In this case as well, there are problems in that mounting is difficult and the surface of the photoconductor is not flat and has slight protrusions.

Other methods include providing the drum with an eccentric mechanism to increase the diameter of the drum. In this method, the sleeve is not completely supported by the drum surface, and the sleeve flattens out at the gap created by increasing the circumference of the drum.

SUMMARY OF THE INVENTION In accordance with the present invention, the drum is fitted with an axially removable key member or wedge member which defines the circumferential surface of the drum. When the key member is removed, the circumference of the drum is slightly reduced, allowing the seamless photoconductor sleeve to slide onto the drum. The key member (which should preferably be tapered) is then reinserted and the
The circumference of the drum returns or increases in circumference and the sleeve is locked in place.

5-=4- The present invention has the advantage that the seamless sleeve is firmly attached to the drum and the photoconductor is supported on its entire surface. The present invention also has the advantage that photoconductor sleeves can be easily and economically inspected at the customer's site where the copier is installed.

DESCRIPTION OF THE EMBODIMENTS The drums of embodiments of the present invention are formed of a suitable material having some flexibility. As shown in FIG. 1, these drums are constructed so that all their peripheral parts are not directly supported by the shaft 4.

In FIG. 1, the outer peripheral part 1 of the drum is attached to a shaft 4 by means of an axially extending connecting part. When the key member 5 is withdrawn from the drum, a void portion 3 is created and, due to the flexibility of the material of the drum, the outer circumferential portions l approach each other so that the circumferential length is the same as that in which the key member was inserted. slightly shorter than the time.

That is, the diameter of the drum when the key member 5 is removed is slightly smaller than the diameter 61 of the drum when the key member is attached. The flexibility of reduces the drum diameter.

The photoconductor sleeve 2 is made as a continuous or endless surface and the diameter of this sleeve 2 is slightly larger than the diameter of the drum when the key member 5 is removed. The photoconductor sleeve 2 is fitted onto the drum and slid into position.

As shown in FIG. 2, the key member 5 is inserted into the cavity 3. It is desirable that a groove be provided on the end surface of the outer circumferential portion 1 facing the gap portion 3 to serve as a guide portion for the key member 3. As the key member 5 is inserted in the direction of arrow 6, the diameter of the drum increases slightly to firmly support the photoconductor sleeve and prevent slip movement.

In a preferred embodiment, the key member 5 is provided with a tapered portion for fitting into the guide groove of the outer peripheral portion 1.

[Brief explanation of the drawing]

Figure 1 shows the drum with the key part removed and the photoconductor sleeve partially fitted onto the surface of the drum; Figure 2 shows the photoconductor sleeve fully fitted onto the drum surface. FIG. 1...Outer peripheral portion, 2...Photoconductor sleeve, 3
...Gap part, 4...Shaft, 5...Key part. Applicant International Business Machines
Corporation agent Patent attorney Hitoshi Yamamoto (1 other person) 8-

Claims (1)

[Claims] A part of a cylindrical body supported by a rotating shaft along the rotating shaft is removable, and when the part is removed and the diameter of the cylindrical body is made smaller than the original diameter before the removal, an endless light is produced. A method of securing a photoconductor sleeve to a cylinder comprising fitting the conductor sleeve into the cylinder and returning the portion to the cylinder to return the drum to the optical diameter.