A hydrostatic drive system for a vehicle (10) comprises an open circuit (100), a closed travel circuit (120), an electronic controller (320), and a main variable displacement hydraulic pump (102) driven by an internal combustion engine (12) equipped with a speed sensor (350). The main variable displacement hydraulic pump may be configured to supply hydraulic fluid to a hydraulic consumer (34, 44, 50) via a hydraulic supply line (106). A pressure relief valve (118) may be connected to a reservoir (300) and may be permanently connected to the hydraulic supply line of the open circuit. The electronic controller may be configured to run a strong braking mode in which the electronic controller at least partially increases the displacement of the main variable displacement hydraulic pump such that hydraulic fluid is discharged via the permanently connected pressure relief valve into the reservoir if the sensed engine speed is higher than a predetermined maximum engine speed.
Closed loop drive circuit with external brake assist
2016-10-04
Patent
Electronic Resource
English
IPC: | F16D COUPLINGS FOR TRANSMITTING ROTATION , Nicht schaltbare Kupplungen / B60T Bremsanlagen für Fahrzeuge oder Teile davon , VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF / E02F Baggern , DREDGING / F04B Verdrängerkraft- und Verdrängerarbeitsmaschinen für Flüssigkeiten , POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS / F15B SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL , Druckmittelbetriebene Systeme allgemein / F16H Getriebe , GEARING |