US Patent 10167971 Aspirated relief valve for a turbocharging system

Engine systems have an air induction system, a turbocharger in fluid communication with an intake manifold, an evacuator defining a Venturi gap with a suction port in fluid communication therewith, a relief valve enclosing a piston and defining an inlet and an outlet in selective fluid communication with one another, and a storage tank of high pressure air in fluid communication with the evacuator. The relief valve has a valve element connected to the piston, and the piston divides the housing into a pressurized chamber in fluid communication with the suction port of the evacuator and a bypass portion in fluid communication with the inlet, which is in fluid communication with the compressed air from the turbocharger, and the outlet, which is in fluid communication with the air induction system or atmosphere. A discharge cone of the evacuator is in fluid communication with atmosphere or the air induction system.