Auxiliary safety braking system

Claim 1

AN AUXILIARY BRAKE APPLYING MECHANISM ADAPTED FOR USE WITH A FORCE APPLYING BRAKE LEVER AND COMPRISING AN AUXILIARY BRAKE OPERATING ROD HAVING A LOST MOTION OPERATIVE ASSOCIATION WITH THE BRAKE LEVER, SPRING MEANS CONNECTED TO SAID BRAKE OPERATING ROD AND COMPRESSIBLE TO A PRELOADED POSITION TO SHIFT THE ROD TO AN INOPERATIVE POSITION WITH RESPECT TO NORMAL OPERATION OF THE BRAKE LEVER, DIAPHRAGM MEANS CONNECTED TO SAID SPRING MEANS, CONDUIT MEANS CONNECTING SAID DIAPHRAGM MEANS WITH A SOURCE OF FLUID PRESSURE, A HOUSING HAVING A FIRST BORE IN CONSTANT COMMUNICATION WITH SAID CONDUIT MEANS, A FIRST VALVE MEMBER IN SAID FIRST BORE CONTROLLING A LATERAL PASSAGE IN THE HOUSING, A SECOND BORE IN SAID HOUSING IN CONSTANT COMMUNICATION WITH SAID FIRST BORE, A SECOND VALVE MEMBER IN SAID SECOND BORE, A THIRD BORE IN COMMUNICATION WITH SAID LATERAL PASSAGE AND WITH SAID DIAPHRAGM MEANS, RESPECTIVELY, SAID HOUSING HAVING A PAIR OF PORTS SPACED FROM THE POINT OF COMMUNICATION BETWEEN SAID FIRST AND SECOND BORES AND SPACED FROM EACH OTHER AND COMMUNICATING WITH ONE ANOTHER THROUGH SAID SECOND BORE WITH ONE PORT LEADING TO THE DIAPHRAGM MEANS AND THE OTHER PORT VENTING TO ATMOSPHERE, VALVE SPRINGS URGING SAID FIRST AND SECOND VALVE MEMBERS TO POSITIONS RESPECTIVELY CLOSING SAID LATERAL PASSAGE AND OPENING THE PORT LEADING TO THE DIAPHRAGHM MEANS WITH FORCE TENDING TO SHIFT THE VALVE MEMBERS TO THE AFORESAID POSITIONS WHEN THE PRESSURE OF FLUID FALLS BELOW A PREDETERMINED SAFE OPERATING LEVEL AND SAID VALVE MEMBERS BEING SHIFTED AGAINST THE ACTION OF THE VALVE SPRINGS BY THE FLUID PRESSURE WHEN IT IS ABOVE THE PREDETERMINED SAFE OPERATING LEVEL FOR OPENING SAID LATERAL PASSAGE TO EFFECT COMPRESSIONOF THE SPRING MEANS BY SAID DIAPHRAGM MEANS AND FOR CLOSING THE PORT LEADING TO THE DIAPHRAGM MEANS WHEREBY, UPON FAILURE OF THE PRESSURE TO BELOW THE PREDETERMINED SAFE OPERATING LEVEL, THE VALVE SPRINGS URGE SAID FIRST AND SECOND VALVE MEMBERS TO THE AFORESAID POSITIONS WITH THE SAID ONE PORT LEADING TO THE DIAPHRAGM MEANS COMMUNICATING THROUGH THE SECOND BORE WITH THE SAID OTHER PORT VENTING TO THE ATMOSPHERE WHEREBY TO VENT THE DIAPHRAGM MEANS AND PERMIT THE SPRING MEANS TO EXPAND AND ACTUATE THE BRAKE OPERATING ROD.