Browse Prior Art Database

Method for Pre-Sizing Copier Magnetic Brush Shells

IP.com Disclosure Number: IPCOM000049524D
Original Publication Date: 1982-Jun-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 2 page(s) / 27K

Publishing Venue

IBM

Related People

Fabrello, AR: AUTHOR [+2]

Abstract

An extruded piece of aluminum tubing may be used as the shell of a magnetic brush in a copier. The run-out of the aluminum tubing must be held to a very tight tolerance. (Run-out refers to surface variation of the tubing as the tubing is rotated). In the past, the tubing was extruded and then machined to the desired outside diameter tolerance and straightness. The difficulty arises in that machining to the desired outside diameter reduces the depth of grooves in the outside surface of the tubing. The grooves are put in the tubing when the tubing is extruded. The process described herein solves this problem by extruding the tube at a diameter slightly larger than required and then shaping the tube to the desired straightness and circularity (run-out) in a compression die.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 92% of the total text.

Page 1 of 2

Method for Pre-Sizing Copier Magnetic Brush Shells

An extruded piece of aluminum tubing may be used as the shell of a magnetic brush in a copier. The run-out of the aluminum tubing must be held to a very tight tolerance. (Run-out refers to surface variation of the tubing as the tubing is rotated). In the past, the tubing was extruded and then machined to the desired outside diameter tolerance and straightness. The difficulty arises in that machining to the desired outside diameter reduces the depth of grooves in the outside surface of the tubing. The grooves are put in the tubing when the tubing is extruded. The process described herein solves this problem by extruding the tube at a diameter slightly larger than required and then shaping the tube to the desired straightness and circularity (run-out) in a compression die.

The process is shown below. First, the core is extruded with grooves at the desired depth in the surface of the tube. The diameter of the tube is slightly greater than that desired in the final shell. Next, the shell or tubing is placed in a compression die. A Grotnes CIRCUMPRESSES* die may be used. The die stops are set for the desired final outside diameter of the shell. The die is driven to compress the shell to its desired outside diameter. This compression does not change the depth of the grooves in the surface of the shell.

A shell manufactured in accordance with the above process has been held to a total run-out tolerance of less than .004...