To provide a positive displacement pump that simplifies its structure and also improves the extent of sealability, thereby making it usable as a liquid pump even if a gaseous body exists on top of the liquid.
This pump is composed of installing a driving shaft 14 having an outer circumferential cylindrical surface 14a and a radial inner circumferential cylindrical surface 14b whose both ends are opened to the former 14a, and rotating around a center axis of the said outer circumferential cylindrical surface, a housing member 28 fitted in with this driving shaft 14, a piston member 26 having an outer circumferential surface 26d to be inserted into the inner circumferential cylindrical surface 14d of the driving shaft 14 and a sliding guide part 26a being orthogonal with the center axis of the outer circumferential surface, and a driven shaft 27 having a key part 27a being fitted in the sliding guide part 26a and the outer circumferential cylindrical surface. In addition, it is also provided with a bearing member supporting the outer circumferential cylindrical surface 14a of this driven shaft member 27 as being eccentric to the driving shaft 14 as a constituent element, through which volumetric capacity of an operating space surrounded by the driving shaft, the housing member and the piston member is varied to some extent by a reciprocating motion of the piston member, and thus a fluid is transferred.
HAYASE ISAO
TOJO KENJI
MIZUNO TAKAO
TOMITA YOSHIKATSU
MATSUNAGA MUTSUNORI
HITACHI SHIMIZU ENG KK