Chuck for large lathe - has three radial jaws actuated by rotating screwed rod driven by hydraulic motor

摘要

A chuck for a large lathe has a cylindrical body with three radially sliding jaws. The jaws are actuated by a tangentially moving tubular shaft with inclined splines which engage matching grooves in the jaws. The tubular shaft has an internal screw thread which engages a rotating rod. The rod is driven from a Gerotor (RTM) hydraulic motor mounted in the body. The motor is fed with oil from holes in the lathe spindle which are in turn supplied from a stationary ring surrounding the spindle and fitted with oil seals.