Self-modulating air bleed apparatus and method for internal combustion engine

Claim 1

In an internal combusion engine comprising a carburetor throat for producing a fuel-air mixture, an intake chamber maintained at a partial vacuum by the engine, a throttle valve located between the carburetor throat and the intake chamber, a spark distributor including a vacuum-controlled spark advance unit, a spark advance control port in the carburetor throat adjacent the throttle valve, a first conduit for connecting the spark advance unit to the control port, and a second conduit connected to the intake chamber, improved apparatus for automatically regulating the amount of air admitted into the intake chamber in response to varying engine load conditions comprising in combination: a valve body for defining a first chamber, a second chamber and a valve seat, first channel means for continuously admitting air into the second conduit, means for manually adjusting the size of the first channel means in order to regulate the amount of air flowing into the intake chamber through the first channel means, second channel means for admitting air into the second conduit, separation means for cooperating with the valve seat to separate the first chamber, the second chamber and second channel means, said separation means being moved from the valve seat in response to an increasing vacuum signal differential and being moved toward the valve seat in response to a decreasing vacuum signal differential, third conduit means for connecting the second chamber to the second conduit, and fourth conduit means for connecting the first chamber to the first conduit, said separation means being movable away from the valve seat to permit air flow into the second chamber via the second channel means when the vacuum signal differential increases, whereby in operation, the combustion of the fuel-air mixture is improved and exhaust emissions are reduced.

Claim 11

A method of automatically regulating the amount of air admitted into the intake chamber of an internal combustion engine having a carburetor throat for producing a fuel-air mixture, a throttle valve located between the carburetor throat and the intake chamber, said throttle valve being rotatable into an idle position in which the flow of the fuel-air mixture into the intake chamber is substantially reduced and rotatable into an open position in which the flow of the fuel-air mixture into the intake chamber is substantially unrestricted, a spark distribuor including a vacuum-controlled spark advance unit and a control port in the carburetor throat adjacent the throttle valve, a first conduit for connecting the spark advance unit to the control port, an engine crankcase, a vent for transmitting crankcase fumes, a second conduit for connecting the crankcase vent to the intake chamber, a first channel between the atmosphere and the second conduit, and a second channel between the atmosphere and the second conduit, said method comprising the steps of: opening the first channel so that air is continuously admitted to the intake chamber; closing the second channel in response to a vacuum signal when the throttle valve is in the idle position and the open position; and opening the second channel when the throttle valve is between the idle position and the open position in response to a higher vacuum signal whereby combustion of the fuel-air mixture is improved and exhaust emissions are reduced.

Claim 12

A method of automatically regulating the amount of air admitted into the intake chamber of an internal combustion engine having a carburetor throat for producing a fuel-air mixture, a throttle valve located between the carburetor throat and the intake chamber, said throttle valve being rotatable into an idle position in which the flow of the fuel-air mixture into the intake chamber is substantially reduced and rotatable into an open position in which the flow of the fuel-air mixture into the intake chamber is substantially unrestricted, a spark distribuor including a vacuum-controlled spark advance unit and a control port in the carburetor throat adjacent the throttle valve, a first conduit for connecting the spark advance unit to the control port, an engine crankcase, a vent for transmitting crankcase fumes, a second conduit for connecting the crankcase vent to the intake chamber, a first channel between the atmosphere and the second conduit, and a second channel between the atmosphere and the second conduit, said method comprising the steps of: opening the first channel so that air is continuously admitted to the intake chamber; closing the second channel in response to a vacuum signal when the throttle valve is in the idle position and the open position; and opening the second channel when the throttle valve is between the idle position and the open position in response to a higher vacuum signal whereby combustion of the fuel-air mixture is improved and exhaust emissions are reduced.