METHOD TO CONTROL OPERATION OF POWER DRIVE Russian patent published in 2008 - IPC B60T17/22 B60T13/24 

FIELD: railway transport.

SUBSTANCE: invention relates to power drives of pneumohydraulic type, particularly, to automatic parking brakes of railway vehicles. Proposed method to control operation of power drive including working medium source, control of and actuating members comes to evaluation of facts of straight and return displacements of fixing member at operation of power drive and when power drive stops its operation. Straight and return displacement of fixing member is initiated by potential energy of force of additional elastic body onto said member. Said action is effected at appearing of preset level of working medium gauge pressure acting onto actuating member and corresponding displacement of the latter. In process of operation of power drive, straight displacement of fixing member including rod arranged in housing-bushing installed in cover of cylinder of power drive is initiated by action onto rod by force realized by potential energy of working medium used in power drive at which rod is displaced and acts onto contact element with subsequent switching on of signaling. When power drive stops it action, return displacement of rod is provided by force action onto rod at corresponding movement of actuating member to release position at which action of rod onto contact element is stopped which leads to switching off of signaling.

EFFECT: improved reliability.

3 dwg