VENTURI DEVICE OF EVAPORATOR

PROBLEM TO BE SOLVED: To reduce the number of part items and enhance the assembling property in an evaporator having a small Venturi on the upstream side of the main nozzle of a Venturi part by mounting the small Venturi by fitting a plurality of radially extending beams fixed to the circumference of a cylindrical body to grooves provided on the inner wall surface of an intake passage. SOLUTION: A main nozzle 6 opened to the part of a large Venturi 2 within an intake passage 5 and a main jet 7 opened to a float chamber 81 are provided within an evaporator body 1, and a small Venturi 10 consisting of a flexible material such as soft resin is arranged just on the upstream side of the main nozzle 6. The small Venturi 10 has a cylindrical body 14 tapered toward the downstream side of the intake passage 5. Four radially extending beams 11 to be provided at circumferentially equal intervals are fitted to grooves 12 cut in the intake passage inner wall surface 51 of the evaporator body 1, whereby the mounting of the small Venturi 10 is performed.