Patent ID: 7140477

Claim:
A parking brake for a railway vehicle brake system, said rail vehicle brake system including a brake cylinder having a push rod connected to brake rigging wherein pressurization of said brake cylinder moves said push rod in a first direction to cause said brake rigging to apply brakes on said rail vehicle, said parking brake comprising: a. a split ring clamp with first and second opposing ends thereof, defining an open state corresponding to a greater distance between said first and second opposing ends, and a locked state corresponding to a lesser distance between said first and second opposing ends, said clamp encircling at least a portion of said push rod; c. a compression member having a lower end rotatably associated with said first opposing end of said split ring clamp member and an upper end connected to an actuator; d. a tension member positioned parallel with said compression member, said tension member having a length greater than said compression member, said tension member having a lower end rotatably associated with said second opposing end of said split ring clamp and an upper end connect to said actuator; and e. a lever arrangement connected between said split ring clamp and said actuator, said lever arrangement connected to each of said first and second opposing ends, said actuator causing said lever arrangement to move said split ring clamp between said open and locked states by varying the distance between said first and second opposing ends; and f. a pneumatic cylinder enclosing a double acting piston, and said double acting piston having a rod end connected to said lever arrangement for moving said split ring clamp between said open and locked states responsive to pressure in said pneumatic cylinder, g. wherein movement of said upper end of each of said parallel compression and tension members results in rotation thereof about said lower ends thereof to cause said first and second opposing ends of said split ring clamp to move between said open state and said locked state, respectively, depending upon a direction of said rotation.