JPH1071439A - Production of developing sleeve for copying machine or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To greatly reduce production cost by substantially forming an end part to a cylindrical shape with a diameter smaller than a diameter of a tubular stock and a thickness larger than its thickness. SOLUTION: While a non-magnetic metal tube of aluminum, etc., is restricted/ rotated between a mandrel 2 and restricting frame 3, the end is formed into a truncated conical body by applying pressing force to the end part of a tube 1 with a first die. By applying pressing force to the end part of a truncated conical shape of a tube 1 by using a second die, the end part is formed into a cylindrical body. Further, the end part is thrusted to be thicknened by using a third die. The end part is further thickened by using a fourth die. A tube stock 11 is, while rotating, pressed in the axial direction by using a fifth die 8 and has its end part thrusted into a cylinder hole 8a to be further thickened. Thus, the end part of a tube stock 11 is formed into the one having a diameter smaller than the diameter of the tubular stock 11 and a thickness larger than the thickness of the tubular stock. By this method, the developing sleeve is produced in short time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a developing sleeve for use in a copying machine or a computer printer.

[0002]

2. Description of the Related Art Recently, in a copying machine or a printer of a computer, there is a tendency that a developing sleeve for supplying toner in a toner reservoir to a photosensitive drum and a toner reservoir are unitized and disposable in order to facilitate handling by a user. There is. Such units need to be as inexpensive as possible. Unexamined Japanese Patent Application No.
In the developing sleeve described in JP-A-2700082, a lid member serving as a journal portion is press-fitted into an open end of a pipe material of aluminum, an aluminum alloy, or a nonmagnetic metal,
It was made by caulking the end of the pipe blank against the lid member. Also, JP-A-57-103741, JP-A-58-221624 and JP-A-62-174
Japanese Patent Application Laid-Open No. 3-224835 discloses thickening of a tube material by pressure drawing.

[0003]

Problems to be Solved by the Invention
In the configuration described in Japanese Patent Application Publication No. 0082, the lid member serving as the journal portion is manufactured separately from the pipe material, and the end of the pipe material is cut to match the outer diameter of the lid member. Since the lid member is press-fitted, a considerable manufacturing cost is required. The thickening described in JP-A-57-103741 is not practical for producing a developing sleeve from aluminum or an aluminum alloy or the like by press-drawing at the point that buckling is likely to occur because a core metal is not used. Absent. Further, the processing methods described in JP-A-58-221624 and JP-A-63-224835 are
This method is not suitable for forming a developing sleeve that requires high quality and high accuracy because the material is heated and a split die is used.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the manufacturing cost by manufacturing a developing sleeve by merely performing pressure drawing or pressure bending and finish cutting on a pipe material of aluminum or an aluminum alloy or a non-magnetic metal. It is. Another object of the present invention is to produce a developing sleeve by using a low-cost press-drawing process which is excellent in work stability and quality stability and does not heat a material.

[0005]

In order to achieve the above object, the present invention provides a method for applying a pressing force to an end of a tubular material by using a first mold having a conical hole. Forming said truncated cone by applying a pressing force to said frusto-conical end of said tubular material using a second mold having a cylindrical bore. Developing the developing sleeve of a copying machine or the like, including the step of forming the frustoconical end into a substantially cylindrical shape with a diameter smaller than the diameter of the tubular material and greater than the thickness of the tubular material. A method of manufacturing is provided.

[0006]

In the present invention, the tubular material is axially pressed while being constrained between the cored bar and the constraining frame, and pressed into the conical hole of the first mold while being rotated. The end of the tubular material is frusto-conical, then the end is pushed into the cylindrical hole of the second mold to form a cylinder, and the end is inserted into the cylindrical hole of a third mold. The part is pushed in and made thick.

[0007]

1 to 5 show a method for manufacturing a developing sleeve according to an embodiment of the present invention.

In a first step shown in FIG. 1, a pipe material 1 made of aluminum, an aluminum alloy, or a non-magnetic metal is axially added while being restrained and rotated between a stepped core 2 and a restraining frame 3. The end is pushed into the conical hole 4a of the first mold 4 by being pressed, and the end of the pipe blank 1 is formed into a truncated conical shape. The cored bar 2 includes a first cylindrical portion 2a having an outer diameter slightly smaller than the inner diameter of the pipe blank 1 and a second cylindrical portion 2b having an outer diameter smaller than the outer diameter of the first cylindrical portion. Have. In addition, core metal 2
May have a step 2c between the first cylindrical portion 2a and the second cylindrical portion 2b according to the finished shape of the developing sleeve.

In the second step shown in FIG. 2, the pipe material 1 whose end is formed into a frusto-conical shape in the first step rotates while being restrained between the cored bar 2 and the restraining frame 3. The cylindrical hole 5 of the second mold 5 is pressed in the axial direction.
The end is pushed into a to form a cylindrical shape. The cylindrical hole 5 a of the second mold 5 has an inner diameter smaller than the outer diameter of the pipe blank 1, and the second mold 5 is
It may have a step 5c corresponding to c.

In a third step shown in FIG. 3, the pipe material 1 having a cylindrical end portion in the second step is rotated while being restrained between the cored bar 2 and the restraining frame 3 in the axial direction. And the cylindrical hole 6a of the third mold 6
The end is pushed into the wall to make it thick. The cylindrical hole 6a of the third mold 6 has a diameter larger than that of the cylindrical hole 5a of the second mold 5 and has a smaller axial length, and the inner diameter of the hole 6c is 2 is slightly larger than the outer diameter of the second cylindrical portion 2b.

In a fourth step shown in FIG. 4, the pipe material 1 whose end is thickened in the third step is rotated while being restrained between the cored bar 2 and the restraining frame 3 while being rotated in the axial direction. And the end is pushed into the cylindrical hole 7a of the fourth mold 7 to make it thicker. The cylindrical hole 7a of the fourth mold 7 has a smaller axial length and a larger diameter than the cylindrical hole 6a of the third mold 6, and the inner diameter of the hole 7c is 2 is slightly larger than the outer diameter of the second cylindrical portion 2b.

In a fifth step shown in FIG. 5, the pipe material 1 whose end is thickened in the fourth step is rotated while being restrained between the cored bar 2 and the restraining frame 3 while rotating in the axial direction. And the end is pushed into the cylindrical hole 8a of the fifth mold 8 to make it thicker. The cylindrical hole 8a of the fifth mold 8 has a smaller axial length and a larger diameter than the cylindrical hole 7a of the fourth mold 7,
The inner diameter of c is slightly larger than the outer diameter of the second cylindrical portion 2b of the metal core 2.

[0013] In a sixth step (not shown), the pipe blank 1 whose end is made considerably thick in the fifth step is finished with an inner and outer diameter of the end by cutting, and a part of the end. The flattened provides a detent.

In the manufacturing method described above, steps 3 and 4 can be omitted depending on the thickness of the finished end of the pipe blank 1.

[0015]

As described above, the method for manufacturing the developing sleeve according to the present invention is only required to perform pressure drawing or pressure bending and cutting on a pipe material of aluminum, an aluminum alloy or a non-magnetic metal. Since the developing sleeve can be manufactured in a short time, the manufacturing cost is greatly reduced.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a first step of a method for manufacturing a developing sleeve according to one embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a second step of the method.

FIG. 3 is a schematic sectional view showing a third step of the method.

FIG. 4 is a schematic sectional view showing a fourth step of the method.

FIG. 5 is a schematic sectional view showing a fifth step of the method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe material 2 Core metal 3 Restraining frame 4 First mold 4a Conical hole 5 Second mold 5a Cylindrical hole 6 Third mold 6a Cylindrical hole 7 Fourth mold 7a Cylindrical hole 8 Fifth mold 8a Cylindrical hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location G03G 15/09 G03G 15/09 Z

Claims (2)

[Claims] 1. A step of applying a pressing force to an end of a tubular material by using a first mold having a conical hole to make the end substantially frustoconical, and a cylindrical hole. By applying a pressing force to the frusto-conical shaped end of the tubular material using a second mold having the following shape, the frusto-conical shaped end is reduced in diameter from the diameter of the tubular material. Producing a developing sleeve for a copying machine or the like, comprising the step of forming a substantially cylindrical shape having a smaller diameter and a thickness greater than the thickness of the tubular material. 2. The method according to claim 1, further comprising the step of cutting the substantially cylindrical end to finish the inner and outer diameters and flattening a part of the cylindrical surface of the end. For producing a developing sleeve for a copying machine or the like.