Premixing device and hot-water supply apparatus

Abstract

A premixing device includes: a main pipe of a cylindrical shape, which is disposed so as to surround an air passage and has a fuel chamber of an annular shape, which is formed inside a pipe wall; a butterfly valve having an air inlet hole and rotatably disposed so as to be located within the air passage; at least one support part which internally has a fuel passage communicating with the fuel chamber and extends radially inward from an inner wall surface of the main pipe so as to be located within the air passage downstream of the butterfly valve; and a venturi ring supported by the at least one support part so as to be located within the air passage downstream of the butterfly valve. The fuel passage has an outlet opening into a space of the air passage on an inner circumferential side of the venturi ring.

Dependencies are inferred from the claim text.