Patent ID: 6546722
Filing Date: 2003-04-15
Classification: F01N,Y10T

Abstract:
An engine exhaust assembly, comprising:a partitioning member provided in a pipe of a silencer arranged in the engine exhaust assembly for dividing the pipe into at least two exhaust passageways; a valve mechanism for causing variation in a surface area of one of the exhaust passages; means for driving the valve mechanism to vary the surface area of said one of the exhaust passages; a connecting member for operably joining the valve mechanism to the driving means; and a diaphragm located between said driving means and the connecting member; wherein said driving means is connected to a throttle valve chamber of a carburetor through a bypass controller and a check valve; and said driving means drives the diaphragm by applying negative pressure from the throttle valve chamber thereto, said bypass controller controls the amount of negative pressure applied from the throttle valve chamber, and said check valve sets the amount of negative pressure to be applied from the throttle valve chamber within a predetermined range.