Importance

Loading Importance Indicators...

Abstract

There is disclosed an hydrostatic transmission having a control and regulating device for adjusting the driving torque with superimposed output power limit regulation, the transmission comprising a drive unit comprising an hydraulic pump having a variable output, and an hydraulic motor arranged to be operated by the hydraulic pump; a servo-adjusting device arranged to control the output of the hydraulic pump in order to adjust the working pressure in the transmission, said device comprising a servo piston arranged for two-way adjustment of the hydraulic pump in two directions, and a control valve arranged to subject the servo-piston to an adjusting pressure so that the piston can adjust the operation of the hydraulic pump; a servo-valve spool provided in said control valve and arranged, in dependence upon the desired direction of adjustment of the hydraulic pump, to be subjected on the one hand to a control pressure and on the other hand to the working pressure prevailing in the transmission or a regulating pressure proportional to the working pressure; an arbitrarily variable operating device comprising a pressure regulator for adjusting said control pressure from a constant supply pressure provided by an auxiliary pump; and a regulating valve arranged to limit the control pressure, or indirectly the supply pressure, and adjustable in dependence upon the amount of working fluid running through the drive unit whereby the regulating valve operates in dependence upon the discharge amount through the drive unit only when a predetermined minimal discharge amount is reached.

Loading the Abstract Image...

First Claim