Hydraulic motor for rotating the bucket of an excavating machine

摘要

The clam-shell bucket of an excavating machine is rotatably connected with the arm or boom of the machine by a hydraulic motor which also provides passages for transmitting pressure fluid from the body of the machine to jacks opening and closing the bucket. Radial cylinder bores in the stator of the motor contain respective pistons and spherical cam followers which engage a radially undulating cam face of the rotor when sequentially supplied with hydraulic fluid by a distributor rotating with the rotor in an axial bore of the stator. The passages for the fluid supply of the bucket jacks extend partly in the rotor and partly in the stator and communicate through a bearing interface remote from the distributor and the axial bore containing the same.