Patent ID: 7213672

Claim:
A hydrostatic transmission circuit for a vehicle having at least two displacement members driven by at least one hydraulic motor having a feed main duct and a discharge main duct a pressurized fluid source connected to said motor via the feed main duct, and skid control means for controlling skidding of at least one displacement member, which means comprise a skid control valve disposed on one of said main ducts and having a constriction of variable section, detection means for detecting a situation in which said displacement member is skidding, and control means suitable for adjusting the section of said constriction as a function of the detected situation, said skid control means for controlling skidding of said displacement member further comprising an additional valve disposed in parallel with the skid control valve, on a branch of the main duct on which said skid control valve is disposed, said additional valve having a first end position in which its through section thereof is at its maximum and a second end position in which said through section is at its minimum, and being suitable for being caused to move between its end positions by the control means.