Sampuntensili’s G 250 generating and profile grinding machine, available from Star SU, is designed for cylindrical gears with a maximum outer diameter of 250 mm and shafts as long as 550 mm. Using a dual work spindle concept, the machine loads/unloads in masked time while simultaneously grinding another workpiece. For micron-level accuracy and shorter change-over times, gear meshing is performed directly from the grinding position. High rotational and linear accelerations, along with their appropriate absolute speeds, make for shorter cycle times and, according to the company, positions the machine to anticipate future grinding tool developments.
Because of the 40-mm minimum axis distance between worktable and grinding wheel, combined with the 12,000-rpm grinding spindle, the machine can use small-OD profile or threaded grinding wheels. This eases grinding of workpieces like shoulder-type gears, which have tool diameter limitations. Similarly, double and triple pinions with very small distances can be ground with the proper tooth-to-tooth alignment. An optional 24,000-rpm spindle multiplier add-on enables the use of electroplated cubic boron nitride profile grinding wheels with outer diameters as small as 25 mm. In addition, grinding spindle’s large tool capacity enables the use of long grinding worms. For mass production environments, a universal quick-change clamping system provides rapid tool change.
Featuring rigid and precise positioning via the rotating worktable, the profile dressing unit uses a diamond dressing roll mounted on a dedicated spindle, with an optional diamond OD dressing tool. It can accommodate single-flank, double-flank and multi-rib-type dressing rolls.
A menu-guided operating interface offers simulation capability. In addition, the grinder’s hydraulically actuated swivel arm brings an inspection probe into position and retracts it from the work area during grinding, performing profile, lead and pitch inspection. Results can be printed or stored on a memory device.