| 摘要 |
<p>An emergency lowering system for a vehicle mounted pantograph in which lever actuated trip valves are disposed at opposite ends of the pantograph current collector in a position to be actuated in the event that an overhead contact wire tends to slide off and end of the current collector. The trip valves control a relay air valve which is arranged to supply a relatively large volume of high pressure air to a pneumatic jack wherein the jack is connected to lower the pantograph. In a preferred embodiment the emergency lowering system is adapted to supply air at a higher pressure and larger volume than the normal lowering system whereby the pantograph is lowered at a faster rate in an emergency. For use in a train of vehicles the system includes a pressure responsive switch for detecting initiation of an emergency lowering condition and for providing a signal which can be used to effect lowering of all pantographs in the train if any one pantograph experiences an emergency condition.</p> |
