Valve plate structure of an axial plunger pump
 An improved valve plate structure for use in axial plunger pumps is disclosed. It comprises: (a) a valve plate, which comprises a suction port, a displacement port, and a pressure build-up zone therebetween; (b) a valve cover, which is in close contact with the valve plate, comprises a suction port at a location corresponding to the suction port of the valve plate and a displacement port at a location corresponding to the displacement port of the valve plate; (c) a flow-diverted channel formed in the pressure build up zone of the valve plate; (d) a through hole provided in the bottom of the flow-diverted channel penetrating through the bottom part of the valve plate; (e) a guided channel formed in the valve cover at an interface between the cover and the valve plate abutting the through hole of the flow-diverted channel. The guided channel comprises a receptacle, which can be connected to the guided channel via the through hole, and an oil guided ditch which connects the receptacle with the second displacement port of the cover, whereby a spring-resisted seal device is provided in the receptacle of the guided channel of the valve cover the spring-resisted seal device is structured such that, under normal conditions, its spring force will push against and close the through hole of the valve plate, thus preventing the flow of fluid from the flow-diverted channel to the guided channel. 
Industrial Technology Research Institute
F
F04B
inventional
Chen-Der Chiun Lern Jiun-Jeng Chaur-Chyn
Tsai Fu Chen Luoh