PROCESSES AND DEVICES FOR THE CUTTING OR MACHINING AND BURNISHING OF BALL SURFACES OF WORKPIECES

摘要

A ball turning and burnishing machine comprises a chuck 1 on which a workpiece 2 is mounted and which is rotatable about an axis a, a table 6 rotatable alternately in opposite directions about an axis b which intersects the axis a at a point defining the centre of curvature of the ball', a cutting tool 8 mounted on the table to one side of the axis a and a burnishing tool 11 on the other side of the axis a, diametrally opposite the cutting tool. Operation.-With the table 6 in the position shown in the Figure the tool 8 is moved hydraulically to apply the cut and the burnishing roller 8 is retracted from the workpiece. The table is rotated in the direction of the arrow 13 and the workpiece rotates about the axis a, to form a spherical surface. When the tool 8 reaches the position 81, the tool holder contacts a stop (not shown) which causes the table to stop, the tool to be retracted and the burnishing roller 11 which is now in the position 111 to be advanced into contact with the work. The table 6 then rotates in the opposite direction so that the burnishing tool works the turned surface.