Hand-operated piston pump

摘要

Hand-operated piston pump comprising: a drive shaft (3); a rotor (4) containing a plurality of compression chambers (104), mechanically coupled to the drive shaft (3) and mounted within a housing case (1); a fluid reservoir in said housing case; a stationary valve plate (6) having two separate arcuate grooves (106,306) that alternately communicate the compression chambers (104) with intake and discharge conduits; and a valve body (27) with an upper flange (271) containing said intake and discharge conduits. The valve plate (6) is mounted to float relative to the upper flange (271), o-ring seals or the like being interposed between the valve plate (6) and the upper flange (271) such that the valve plate (6) is separate from the upper flange (271).