초록 ▼

The invention is a venturi of unusual configuration and a method and apparatus for forming such a venturi in a single operation from a rounded, deformable tube. According to the invention, diametrically opposing sides of the tube are inwardly deflected in increasing amounts from opposing ends of the

The invention is a venturi of unusual configuration and a method and apparatus for forming such a venturi in a single operation from a rounded, deformable tube. According to the invention, diametrically opposing sides of the tube are inwardly deflected in increasing amounts from opposing ends of the tube so as to form along the length of the tube from either end a first chamber of increasingly flattened and reduced cross-section followed by a second chamber of decreasingly flattened and reduced cross-section. An elongated throat section of maximally flattened and reduced cross-section may be provided between the first and second chambers, particularly for engine muffler venturis. The tube is conveniently deformed by applying pressure to a pair of its opposing sides along at least a portion of its length, preferably by pairs of opposing dies or eccentric rollers. Venturis for engine mufflers are conveniently fabricated from thin walled steel tubes by cold forming the tubes in the manner described. In cold forming, sidewalls between the flattened walls are typically outwardly bulged as well. The outward bulging may be constrained such that the central throat section has a substantially rectangular cross-sectional shape.

대표청구항 ▼

A muffler defining a portion of a path for exhaust gases from an internal combustion engine comprising a housing and a venturi at least partially within the housing defining a path for exhaust gases passing through the housing, the venturi having a centerline, an inlet section at one end to admit ex

A muffler defining a portion of a path for exhaust gases from an internal combustion engine comprising a housing and a venturi at least partially within the housing defining a path for exhaust gases passing through the housing, the venturi having a centerline, an inlet section at one end to admit exhaust gases, an outlet section at an opposing end to release exhaust gases, a throat section intermediate the inlet section and the outlet section having a transverse cross-sectional area normal to the centerline less than the transverse cross-sectional area normal to the centerline in either the inlet section or the outlet section, a reduction chamber section connecting said inlet section and said throat section and diminishing in transverse cross-sectional area normal to the centerline between the inlet section and the throat section, and an expansion chamber section connecting said throat section and said outlet section and increasing in transverse cross-sectional area normal to the centerline between the throat section and the outlet section, the improvement wherein the venturi is formed from a single length of tubing having a uniform transverse circumferential wall length in planes normal to the centerline at each point along the centerline.