Abstract The amount of pollutants expelled from an internal combustion engine is lowered by bleeding a predetermined amount of ambient air into the conduit which connects a conventional vacuum advance control system with the intake manifold. This results in a retardation of the vacuum advance that otherwise would be obtained and provides a considerable reduction in oxides of nitrogen, CO and hydrocarbons. The vacuum advance bleed control comprises a conduit inserted into the vacuum advance line of an internal combustion engine, with a characterized bleed hole in the conduit, and filter medium for preventing dirt from entering the bleed hole. Flanges on the conduit hold the filter in position and an annular recess is provided in the conduit over the bleed hole. An orifice may be provided in the conduit between the bleed hole and the carburetor.
Bleeding means as in claim 1 wherein said recess extends around the perimeter of the circuit.
Claim 2
Dependent Claim
14 words
Bleeding means as in claim 1 wherein said conduit contains more than one opening.
Claim 3
Dependent Claim
25 words
Bleeding means in claim 1 wherein said flange means is a raised portion extending peripherally around the circumference of the conduit and formed integrally therewith.
Claim 4
Dependent Claim
16 words
Bleeding means as in claim 1 including orifice means in the conduit separate from said opening.
Claim 5
Dependent Claim
27 words
Bleeding means as in claim 5 wherein carburetor means is included on the said engine and the orifice means is between said opening and said carburetor means.
Claim 6
Dependent Claim
14 words
Bleeding means as in claim 1 wherein the filter medium is a foam material.
Claim 7
Dependent Claim
212 words
In an internal combustion engine having a distributor with a vacuum spark advance control system to control the timing of the cylinder spark, said vacuum advance control system including the application of a vacuum from the intake manifold to an advance control in the distributor thoough a vacuum conduit wherein the intake manifold pressure controls the cylinder spark timing, improved means for reducing the spark advance timing, positioned in communication with said vacuum conduit, said reducing means bleeding a predetermined amount of ambient air into the vacuum conduit thereby reducing the vacuum imposed on the advance control in the distributor to lower the spark advance and reduce the amount of pollutants in the engine exhaust, said reducing means comprising a second conduit having at least one opening in the wall thereof opening to ambient air positioned in the vacuum conduit, said opening being covered by a filter media for preventing dirt particles from entering the opening, said opening being positioned in a recess in the wall of the second conduit to space the opening from the filter media, and flange means positioned on the second conduit for holding the filter media in position over the recess and opening and preventing the ends of the vacuum conduit from sliding and covering the opening.
Claim 8
Dependent Claim
29 words
An engine according to claim 8 including an orifice means in said second conduit between said opening and the source of application of the vacuum from the intake manifold.