Railway double acting cylinder control - uses reversible motor to drive pump which operates in only one direction

摘要

The control is for double-acting cylinders, esp. for the drive of points and barriers on railways. A motor- driven pump, which conveys in one direction only, supplies a pressure medium via a path valve to one of two chambers of a cylinder, while the second chamber is relieved via the path valve. The pump (KP) is driven by a reversible motor (A), which switches the path valves (WV) between two positions via a transmission (G) in front of the pump, and dependant upon the direction of the motor. The transmission consists of a helical-toothed spur wheel or helical gear transmission between motor and pump. Its take-off (S2) is displaceable in an axial direction, to control the path valves.