Boom warning actuator

A warning system for use on a crane wherein said crane includes a movable boom, and at least one movable weight bearing line, said system comprising:

• a. a source of fluid under pressure;
• b. a pressure activated signal emitting device;
• c. a plurality of signal device actuators positioned in pressure communication with said source and device;
• d. each of said actuators having a housing and a valve body mounted in said housing for longitudinal movement therein and shiftable between a first position permitting fluid pressure communication between said source and device and a second position blocking said communication, wherein one of said actuators further comprises:
• i. a boom engageable portion of its valve body located outwardly of said housing;
• ii. means internal to said housing for urging its valve body to said second position;
• and
• iii. means for causing said boom engageable portion to shift said valve body to said first position against the force of said urging means;
• and wherein
• e. a second of said actuators further comprises:
• i. first and second body portions, each of said body portions including means for passing said weight bearing line therethrough;
• ii. fluid pressure inlet means provided in said first body portion in fluid pressure communication with a fluid pressure source;
• iii. fluid pressure outlet means provided in said first body portion in fluid pressure communication with a fluid pressure activated signal emitter;
• and
• iv. an elongated valve member mounted at least partially in said first body portion for longitudinal movement therein between a first position permitting pressure communication between said inlet and outlet and a second position blocking such communication.