Patent ID: 8899385

Claim:
A system for retarding the speed of a railcar, the system comprising: a brake; a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of the railcar and an open position in which the brake does not apply braking pressure on the wheel of the rail car; a hydraulic circuit comprising a first manifold and a second manifold; a pump configured to pump hydraulic fluid into at least one of the first manifold and the second manifold; and a first logic element controlling pressure of the fluid in the first manifold such that when the wheel enters the brake and forces the brake towards the open position, the logic element reacts to maintain a selected pressure in the first manifold, thus causing a selected braking pressure to be applied by the brake on the wheel of the railcar; wherein the actuator comprises a piston disposed in a cylinder, wherein the piston extends from the cylinder into an extended position to move the brake into the closed position and wherein the piston retracts into the cylinder into a retracted position to move the brake into the open position; wherein the piston defines a passageway there-through, wherein said passageway facilitates flow of fluid between a cap-side of the cylinder and a rod-side of the cylinder when the piston is moved from the extended position to the retracted position, thus facilitating movement of the brake from the closed position to the open position.