Superfinishing machine, superfinishing method and outer ring of bearing having superfinished raceway surface

摘要

A superfinishing machine and a superfinishing method which can perform axially uniform finishing on a logarithmically crowned surface formed on an inner peripheral surface of an annular member in a short time, and an outer ring of a bearing having a raceway surface superfinished by the superfinishing method, are provided. A superfinishing machine 1 includes a linearly reciprocating mechanism 40 configured to linearly reciprocate a grinding stone 3 held by a pressing section 30, along a plane B touching a generatrix of the logarithmically crowned surface, and in a direction C inclined by a given angle φ with respect to a center axis O of an outer ring 10.

主权项

1. A superfinishing machine comprising:
a rotation jig configured to hold an annular member such that the annular member is rotatable around a center axis of the annular member, the annular member having a logarithmically crowned surface formed on an inner peripheral surface thereof; a pressing section configured to hold a grinding stone and to bring a distal end surface of the grinding stone into pressure contact with the logarithmically crowned surface of the annular member rotating around the center axis; and a linearly reciprocating mechanism configured to linearly reciprocate the grinding stone held by the pressing section, along a plane touching a generatrix of the logarithmically crowned surface, and in a direction inclined by a given angle with respect to the center axis of the annular member, thereby superfinishing the logarithmically crowned surface, wherein the distal end surface of the grinding stone has a quadrangular shape in a cross section when seen from a radial direction and is formed such that a set of opposite sides is parallel to the inclined direction, and each side portion of the distal end surface in a circumferential direction is formed with a portion configured to abut against all locations on the logarithmically crowned surface along the inclined direction.