Machine tool with plural tool spindles

摘要

A circular grinding machine wherein a reciprocable carriage supports a first rotary tool spindle for a relatively large grinding wheel and the housing including the bearing for the first spindle mounts a carrier which is pivotable about the axis of the first spindle by a fluid-operated motor and supports a second tool spindle for a relatively small grinding wheel. The carriage can be advanced to a first position to move the relatively large grinding wheel into coarse material removing contact with a rotary workpiece (such as a camshaft), and the carriage is thereupon retracted to a second position in which the carrier can be pivoted about the axis of the first spindle to move the relatively small grinding wheel into precision-finishing engagement with the pretreated workpiece.