Stability of analogue neural clas-si cation networks

An all-metal check valve for an air injection system of an internal combustion engine includes a valve body defining a chamber between the valve inlet and the valve outlet in which a valve disc is operative to control fluid flow between an air pump and the exhaust manifolds. The valve disc has an outer ring attached to the valve body and a central valve element hingedly connected to the ring by a pair of arcuate flexible arms defined by a pair of concentric diametrically opposed C-shaped slots. The arms are normally flexed for biasing the valve element against a valve seat to block the reverse flow of exhaust gases therethrough. Injection air flow additionally flexes the arms to shift the valve element to an open position for permitting flow from the air pump to the exhaust manifolds.