Hydraulic actuation system for a rail vehicle
AssigneeSchweizerische Lokomotiv-und Maschinenfabrik
InventorsBruno Meier, Otto Luginbuhl
Life of this patent
Estimating the term…
Abstract
The hydraulic activators are provided with a relief valve which serves to permit communication between the disengaging cylinder chamber and the work cylinder chamber. The open position of the relief valve occurs when the release apparatus for the rotatable friction brake member is closed. The closed position of the relief valve occurs after the rotating brake is released. The relief valve can be mounted in the release apparatus of the working piston.
Claims16
An hydraulic brake actuation system for a rail vehicle comprising at least one double-acting reciprocating actuator for selectively engaging and disengaging a brake, said actuator including
- a cylinder;
- a work piston slidably mounted in said cylinder to define a return cylinder chamber on one side and a work cylinder chamber on an opposite side thereof;
- a screw-threaded spindle extending from said piston;
- a reversible screw-threaded connection between said spindle and said work piston to permit rotation of said spindle relative to said piston;
- a friction brake member mounted on said spindle, said member having rotatable brake surface thereon;
- a release means including an insert in said cylinder having a stationary brake surface opposite said rotatable brake surface, and a disengaging piston slidably mounted in said insert to selectively move said friction brake member away from said insert and to define a disengaging cylinder chamber in said insert, said disengaging piston being disposed in facing relation to said rotatable brake member to separate said disengaging cylinder chamber from said work cylinder chamber;
- and
- a relief valve between said disengaging cylinder chamber and said work cylinder chamber, said valve being movable between a closed position for blocking communication between said disengaging cylinder chamber and said work cylinder chamber with said brake surfaces in spaced relation and an open position for communicating said disengaging cylinder chamber with said work cylinder chamber with said brake surfaces in contact with each other.
A hydraulic brake actuation system for a rail vehicle comprising at least one double-acting reciprocating actuator for selectively engaging and disengaging a brake, said actuator including
- a cylinder;
- a work piston slidably mounted in said cylinder to define a return cylinder chamber on one side and a work cylinder chamber on an opposite side thereof;
- a screw-threaded spindle secured to and extending from said work piston;
- a recirculating ball nut rotatably mounted on said spindle and in said cylinder, said nut having a rotatable brake surface thereon;
- a release means including an insert in said cylinder having a stationary brake surface opposite said rotatable brake surface and a disengaging piston slidably mounted in said insert to selectively move said nut away from said insert and to define a disengaging cylinder chamber in said insert, said disengaging piston being disposed in facing relation to said nut to separate said disengaging cylinder chamber from said work cylinder chamber;
- and
- a relief valve between said disengaging cylinder chamber and said work cylinder chamber, said valve being movable between a closed position for blocking communication between said disengaging cylinder chamber and said work cylinder chamber and an open position for communicating said disengaging cylinder chamber with said work cylinder chamber.
Dependencies are inferred from the claim text.