A New Generation of Electro-Hydraulic Control for Hydrostatic Transmissions

The use of electro-hydraulic control of hydrostatic transmissions on mobile equipment has been limited by the high cost, marginal performance, marginal reliability and poor serviceability of previously available controls. Rapidly increasing usage of electronics on mobile equipment has created a strong need for an electro-hydraulic control without these limitations. A design program was established to develop an entirely new control which both overcomes previous limitations and meets future needs. This was accomplished by selecting the proper design concept to allow meeting all design goals, then carefully implementing and thoroughly qualifying the concept in hardware.