Fluid Power Control Technology : Present and Near Future

Abstract

Fluid power control technologies are utilized in precise and heavy-duty motion control of mobile or stationary hydraulic systems. In the Japanese market for hydraulic systems, construction machinery accounts for 40 percent, extending from excavators to construction robots, radio-controlled truck cranes, tunnel cutters, dredges and concrete pumps, as examples. Injection molding, press and processing machines make up 10 to 15 percents of the stationary hydraulic field. Continuous improvement of a mature technology is necessary. Efficiency elevation, noise reduction, promotion of mass-produced electrohydraulics and computer control are urgent issues. From these points of view, this paper introduces some newly developed components with scientific approaches : a coupled fluid force pump/motor with better mechanical efficiency, a sensor-integrated cylinder, compact proportional valves, high-speed switching valves and some hydrostatic drive systems.