GB1534568A - Grinding machine - Google Patents

Abstract

1534568 Grinding ELECTROFABRICATION & ENG CO Ltd 23 Aug 1977 [28 Sept 1976] 40274/76 Heading B3D A machine for shaping the arcuate outer surface of a ring, disc or like circular member, such as a piston ring 6, comprises at least one rotatable grindstone 12 having a surface 14 which is concave and symmetrically disposed about the axis of rotation, support means 4 for locating the member in a plane containing said axis of rotation, and drive means 8 for providing relative rotation between the member and the or each grindstone about the central axis of the member, the concave surface 14 making pressurized contact with the arcuate outer surface of member to impart thereto a curvature in a direction parallel to the central axis of the member. The support means consists of a plurality of rollers 4 freely rotatable about vertical axes on a table 2 and the drive means consists of a pair of drive rollers 8 which frictionally engage the circular member so as to rotate it about its central axis P with its outer surface engaged by the concave surface 14 of the grinding wheel 12 which is adjustable radially of the member. The radius of the concave surface 14 equals the radius of the outer surface of the circular member which is thereby ground to a barrel-like configuration. The circular member is located vertically at the grinding zone by rollers 14 which press the member against upstanding hardened skirts 16 on the table. In other embodiments, a plurality of grindstones may be disposed around the periphery of the circular member, and the latter may be held stationary and the or each grindstone rotated about the ring. The or each grindstone may be pivotable about the region of grinding contact to decrease the radius of curvature ground on the ring.