Patent ID: 8342208

Claim:
A multi-protection valve comprising: an input chamber connected to a compressed air source; first pressure control valves configured to close as a pressure in a service brake circuit reduces; second pressure control valves configured to close as a pressure in a parking brake circuit reduces; a flow path for communicating between the input chamber and the service brake circuit and the parking brake circuit such that air flows from the input chamber to the service brake circuit and the parking brake circuit, the flow path including all the first pressure control valves and all the second pressure control valves; and a bleed air flow path for communicating between the input chamber and the parking brake circuit so as to bypass the flow path, the bleed air flow path having a second check valve for preventing air from flowing from the input chamber to the parking brake circuit, wherein the multi-protection valve further comprises a third check valve provided between a location of communication between the bleed air flow path and the input chamber and the compressed air source to prevent air from flowing from the bleed air flow path to the compressed air source.