No other technology can generate as much linear power in as small a package as a hydraulic cylinder. And with the right design, hydraulic cylinders in closed-loop electrohydraulic systems can also achieve high speed and precise position. Of course, hydraulic cylinders cannot operate as solitary components. They require a flow source, control valves, fluid lines, and usually filters. An alternative to designing a complete system could be the Mini-Motion Package (MMP4) from KYB Americas Corp., Addison, Ill.
KYB's MMP4 is an electric over hydraulic linear actuator featuring an integrated cylinder, motor, pump and valve. The lightweight and compact unit can generate extension forces to 2000 lb.
The MMP4 is a completely selfcontained hydraulic circuit that requires no external piping, which drastically reduces the potential for external oil leakage. Because it is a sealed hydraulic system it has no restrictions on mounting orientation.
Compared to electric actuators, the MMP4 offers better shock absorption, higher standard IP rating (IP 67 weatherproof rating is standard), lower current draw, and no mechanical clutches or gears. Moreover, the MMP4's relief valve can be adjusted for different extension and retraction forces.