METHOD AND MEANS FOR GRINDING BALLS OF CERAMICS OR OTHER HARD MATERIALS TO SPHERICAL SHAPE

摘要

The invention concerns a method to machine roughly shaped ball blanks of hard materials to the shape of spheres with a high sphericity and surface finish. According to the invention, balls of hard materials (e.g. ceramics) are brought to slide against already spherical balls of softer materials (e.g. steel) in a grinding cell (1, 2) under the addition of grinding agents, e.g. diamond grits. With the grinding cell, alternatingly positioned hard and soft balls are pressed against each other in a ring shaped track, defined by the facing surface of two rotationally symmetrical bodies, which are rotated relative to each other, and which exerts both a force axially against the balls, and a force radially inwards, or outwards.