Anti-theft method and apparatus for locking the brakes of a vehicle

An anti-theft apparatus for a wheeled vehicle, the vehicle including a wheel-braking system having at least one conduit for braking fluid such that a) when the fluid moves in one direction in said conduit the brakes are applied, and b) when the fluid moves in the opposite direction in said conduit the brakes are released;

• said apparatus comprising:
• A) valve means including:
• recess means defining a valve chamber,
• within said chamber a valve seat surrounding a passageway,
• a valve member defining a surface which is radially symmetrical about an axis of symmetry, said surface seating against said valve seat, said valve member having internal passage means and being rotatable about said axis of symmetry between 1) a first position in which it blocks fluid flow from said chamber to said passageway and functions as a one-way check valve, and 2) a second position in which it permits fluid flow in both directions along said passage means between said chamber and said passageway,
• and resilient means for urging said valve member against said valve seat,
• B) connecting means adapted to permit the apparatus to be installed in said braking fluid conduit such that when the braking fluid moves in said one direction it passes from said passageway to said chamber, and when the braking fluid moves in said opposite direction it passes from said chamber to said passageway, and
• C) locking means operatively associated with said valve member and adapted a) to move said valve member between said first and second positions, and b) to lock said valve member in said first position.