Pulse piston drive

Claim 1

A pulse piston drive comprising, in combination: a pulse chamber having a guide cavity and a second cavity adapted to receive an energy medium, an opening communicating said guide and second cavities; reciprocable piston means being positioned in said guide cavity; a differential valve in said second cavity adapted to periodically close said opening intermediate said guide and second cavities, said valve including a closure member formed as a hollow piston having an outer peripheral wall in annularly spaced relationship with the surface of said second cavity so as to facilitate axial movement of said hollow piston during flow of said energy medium, said hollow piston dividing said second cavity into first and second portions; annular sealing means on said hollow piston outer peripheral wall maintaining said first and second portions of said second cavity in sealed relationship to each other; channel means extending through the perhipheral wall of said hollow piston facilitating flow of said energy medium into the first portion of said second cavity; means for admitting said energy medium into said first portion of said second cavity; and hydraulically actuated drive means communicating with the second portion of said second cavity for biasing said differential valve into closed position, said hydraulically actuated drive means comprising a hydraulic accumulator mounted on said pulse chamber, said accumulator including a spring-biased non-return valve having a jet nozzle forming pressurized fluid passageway means between said accumulator and the second portion of said second cavity.