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Clifford Harry Allen: Positive displacement rotary pump and drive coupling therefor. Bosworth Sessions & McCoy, February 17, 1976: US03938744 (17 worldwide citation)

A progressing cavity, positive displacement rotary pump assembly for fluid or semi-fluid material. The assembly includes a rotary shaft with an associated drive motor and pump components including a tubular stator with an interior helical surface and an orbital rotor within the stator operably conne ...


2
Clifford H Allen: Positive displacement rotary pump and drive coupling therefor. Bosworth Sessions & McCoy, May 9, 1978: USRE029626

A progressing cavity, positive displacement rotary pump assembly for fluid or semi-fluid material. The assembly includes a rotary shaft with an associated drive motor and pump components including a tubular stator with an interior helical surface and an orbital rotor within the stator operably conne ...


3