Resources Contact Us Home
Variable Venturi carburetor

Image Number 3 for United States Patent #4302404.

A variable venturi carburetor wherein the suction piston is fully closed with respect to the venturi section at engine stop to elevate the negative pressure at the time of cranking, and is opened to a predetermined degree at the time of idling, thereby obtaining stable driving performance at a suitable air-fuel ratio. The suction piston slides, via a spring, into and out from a suction chamber communicating with a mixing chamber via a negative pressure path and has at its head a metering needle to face a metering jet. The low negative pressure occurring in the mixing chamber along with cranking is reliably applied to the gap between the metering needle and the metering jet which is wider than the gap in their matching state at the time of idling. Hence, the engine starts operating with an over-rich air-fuel ratio. The suction piston is shaped in such manner so as to close a venturi section on the upstream side with respect to the base portion of the metering needle at the time of stop of the engine. A venturi-crossing flange is disposed at a location corresponding to the position in the venturi section of either one or both of the suction piston head and a barrel member of the above-mentioned venturi section. Alternatively, an atmospheric pressure is communicated with the negative pressure to the suction chamber in order to enable driving at a set air-fuel ratio with a suitable lift movement.

  Recently Added Patents
Liquid crystal display apparatus
Image processing system, image processing apparatus, control method for image processing apparatus, and storage medium
Integrated emergency medical database system
Differentiated PSIP table update interval technology
Randomly accessible visual information recording medium and recording method, and reproducing device and reproducing method
Methods of prognosing a rheumatoid arthritis remission phenotype
Triple-action pest control formulation and method
  Randomly Featured Patents
Graphic user interface computer icon for a monitor display
Evaluation and treatment of patients with progressive immunosuppression
Ceiling fixture having tiltable foot hanger bars with press fit mounting brackets and slidable and adjustable hanger bars with press fit rotatable end mounting brackets
Top for furniture
Method and device for mobile object information management, and computer product
Automobile vehicle with a wiperless cleaning system for glazed surfaces and the like
Preparation of halogenated primary amines
Stand ring for a square drum
Video production switcher