Patent ID: 8932193
Filing Date: 2015-01-13
Classification: B29C,B29L,B65H

Abstract:
1. A sheet feed rolling element for use in an electrophotographic device, said rolling element being formed by injection molding and including a roller portion having an outer peripheral surface and shoulders on both sides of the outer peripheral surface, each of said shoulders being formed by a curved chamfer; wherein a step is formed fully about a circumference of the rolling element on the curved chamfer of at least one of the shoulders, said step dividing the curved chamfer into a first portion near an end surface of the rolling element and a second portion near the outer peripheral surface, a diameter of said first portion being smaller than a diameter of said second portion; wherein the diameter of said first portion of the curved chamfer gradually decreases from said step to the end surface of the rolling element such that the first portion of the curved chamfer has a first extreme end disposed at said step and a second extreme end disposed at the end surface of the rolling element; wherein the diameter of said second portion of the curved chamfer gradually decreases from the outer peripheral surface of the roller portion to said step such that the second portion of the curved chamfer has a first extreme end disposed at an end of the outer peripheral surface of the roller portion and a second extreme end disposed at said step; and wherein the outer peripheral surface is constituted by a smooth surface, the outer peripheral surface and the shoulders are mutually integral portions of the roller portion, and the outer peripheral surface and the shoulders are both formed of the same material.