Abstract: To avoid manual rotation of the rotary table (3) on the turning slide (2) of an NC (numerical control) coordinate grinding machine having a grinding wheel (1), when a conical region is being ground on a workpiece next to a cylindrical region, an NC controllable rotating devices (14) for the rotary table (3) is mounted on the turning slide (2). A measurement device (18) is also provided, for determining the distance (R) from a reference surface of the conical region and the B axis. After grinding a calibration cylinder, the distance (S) between the grinding line (6) and the C axis is calculated, and the C axis in this rotational position around the B axis is reset ("zeroed") in the computer (9'). This provides sufficient parameters for calculating the grinding program for the workpiece which is to be ground. In this way it is possible to grind automatically and precisely a series of workpieces having simultaneously both cylindrical and conical regions, without the need for manual adjustments.

Abstract: In order to eliminate the need, during operation, to continually redefine the grinding line (SL 2) between the trimming wheel (12) and the gripping wheel (10), and the need to re-zero the C-axis after each trimming step by the grinding wheel (12) on the grinding wheel (10) in a grinding machine, a trimming wheel (12) with a separate drive (11) is mounted directly on the turning slide (1) instead of on the rotary table (2) of the grinding machine. The said grinding line (SL 2) is thus not displaced when the C-axis is zeroed, but rather is held in a defined position with respect to the longitudinal axis (Z-axis) and to the B-axis perpendicular thereto of the grinding machine. To enable the quality and precision of the trimming to be increased, a trimming wheel (12) is employed which can be mounted on a conical receiving piece which is in turn mounted on a shaft having two bearings.

Abstract: To avoid manual rotation of the rotary table (3) on the turning slide (2) of an NC (numerical control) coordinate grinding machine having a grinding wheel (1), when a conical region is being ground on a workpiece next to a cylindrical region, an NC controllable rotating devices (14) for the rotary table (3) is mounted on the turning slide (2). A measurement device (18) is also provided, for determining the distance (R) from a reference surface of the conical region and the B axis. After grinding a calibration cylinder, the distance (S) between the grinding line (6) and the C axis is calculated, and the C axis in this rotational position around the B axis is reset ("zeroed") in the computer (9'). This provides sufficient parameters for calculating the grinding program for the workpiece which is to be ground. In this way it is possible to grind automatically and precisely a series of workpieces having simultaneously both cylindrical and conical regions, without the need for manual adjustments.

Abstract: In order to fabricate turned parts (18) out of a steel rod or bar (13) solely by grinding, the latter is chucked in oppositely disposed collets (14, 16) and is ground by two profiled grinding discs (20, 20') which act on it either sequentially or simultaneously. The two profiled grinding discs are advanced to (and plunged into) the rod or bar (13) (for plunge-cut grinding) at an acute angle of attitude thereto, and said discs rotate on respective axes (D, D') which are inclined with respect to the axis (B) passing through the collects. In this way, surfaces (1', 5, 6, 8, 10) which are perpendicular to the longitudinal axis (A) of the rod or bar and which may even face in opposite directions can be produced without having to rechuck the turned part (18). The usual types of profiled turned part segments (1, 2, 3, 4, 7, 9) may also be produced at the same time.

Abstract: For grinding to size a preform (18), particularly a cast preform, wherewith one or more cyindrical or conical regions (3, 4) and an end region (10) are to be ground to size between centers without re-chucking, a U-shaped intermediate jig (23) is required, whereby the centering chamber (28) of the tailstock (27) is disposed at a location displaced from the tailstock in the direction toward the headstock (25). The bore of the centering chamber extends completely through the jig member (26), and is configured to provide a steadying and centering member, wherewith a portion of the preform (18) can still pass through said chamber. This portion (4, 10) thereby extends free between the headstock (25) and tailstock (27), where said portion can be ground by a grinding wheel (29) which can be extended along the axis of centers (D) beyond the between-centers region into the region between the centering chamber (28) and the tailstock (27).