Fluid pressure operated piston engine assembly

摘要

A fluid pressure operated piston engine assembly, such as a pump assembly, including a fluid pressure operated piston engine and a fluid valve for coupling fluid under pressure to alternative portions of the piston chamber of the piston engine. The fluid valve includes a valve spool which is translated to effect the alternative modes of coupling pressurized fluid to the piston chamber. The translation is accomplished by a shifter assembly having a shifter rod attached to the valve spool. The shifter rod includes a pair of diametrically opposed magnets attached thereto. A fork is attached to the piston engine drive shaft at one end and is mounted for limited movement along the shifter rod between the pair of magnets of the shifter rod. The interaction between the flux generated by a magnet carried by the fork with one of the magnets of the shifter rod causes the shifter rod, and in turn the valve spool, to shift from one position to another, thereby re-directing the flow of fluid to the piston chamber to effect the reversal of direction of travel of the piston and its associated drive shaft.