Patent ID: 6470786
Filing Date: 2002-10-29
Classification: F03C

Abstract:
A radial piston hydraulic engine, comprising:a rotatable box section; a cam ring operatively connected to said rotatable box section; a fixed non-rotary shaft having at least two control pressure channels; a plurality of cylinder bodies fixedly connected to said non-rotary shaft, each of said plurality of cylinder bodies having a piston structured and arranged therein; wherein a selected number of cylinder bodies have a shut-off valve in communication with said at least two control pressure channels of said non-rotary shaft; said at least two control pressure channels are structured and arranged to selectively supply a control pressure to said shut-off valves of said selected number of cylinder bodies; whereby when said control pressure is supplied to said shut-off valve a selected number of pistons are deactivated; a distributor connected to said box section and structured and arranged to rotate therewith, said distributor having at least one channel structured and arranged to communicate a pressurized medium from said non-rotary shaft through said shut-off valves to each of said pistons; an oil space located below said piston and in communication with said shut-off valves; an outlet channel formed in said non-rotary shaft and in communication with said shut-off valves; and wherein each of said shut-off valves comprise: a pin having a central annular channel; and wherein said pin is movable between a first position, in which said central channel of said pin is aligned with said outlet channel and permits a communication between said oil space located below said piston and said outlet channel, and a second position, in which said central channel is out of alignment with said outlet channel thereby preventing a communication between said oil space and said outlet channel.