Abstract: A secondary air supplying apparatus for an internal combustion engine and a gas heating apparatus are provided to enable high-performance exhaust gas purification in a catalytic apparatus of the internal combustion engine, in particular, even at a low-temperature starting time. A secondary air supplying apparatus supplies secondary air to the catalytic apparatus through a secondary air introducing path for communicating the intake side of the internal combustion engine with an exhaust manifold. In the apparatus, a gas heating apparatus having an exothermic body is provided for the secondary air introducing path.

Abstract: A check valve has a valve element 12 integral with a metallic bushing 11 and made of a substantially annular rubber material. A hole is provided in the center of the valve element, and a shaft 13 passes through the hole. A spring 2 is mounted around the shaft, and a back face of the valve element is supported at one end of the spring through the metallic bushing. A truncated conical stopper 4 includes a recess at an intermediate portion, and is mounted downstream of the valve element to restrict the amount of movement and deformation of the valve element. The stopper is fixed at one end 13b of the shaft. It is thereby possible to provide a reliable check valve in which flow resistance can significantly be reduced, and sufficient safety can be established against counter flow pressure.