Liquified petroleum gas carburetor

Claim 1

A liquified petroleum gas carburetor for an internal combustion engine supplied from a tank with an outlet and containing source of liquified petroleum gas maintained at a pressure (P 1 ) wherein the gas is in an equilibrium state, and having a throttle valve in the intake tube controlling the amount of the air fuel charge ingested by the engine through the intake manifold, the carburetor characterized by: a heat exchanger adaptable to be mounted contiguous with the intake manifold and surrounding the intake tube for receiving the liquified petroleum gas in the equilibrium state and discharging liquified petroleum gas in a vaporized state; a first pressure regulator coupled to the outlet of the tank and integral with said heat exchanger to receive the liquified petroleum gas in the equilibrium state and regulate the pressure of the liquified petroleum gas to a second pressure (P 3 ); a second pressure regulator coupled to the output of said heat exchanger and upstream therefrom, said second pressure regulator in the air flow to the throttle valve for receiving said vaporized liquified petroleum gas and regulating its pressure to a third pressure (P 4 ); and a metering valve coupled to said second pressure regulator for discharging said vaporized liquified petroleum gas into the intake tube in response to engine requirements for mixing said vaporized liquified petroleum gas with the flow of air.

Claim 9

A method for metering liquified petroleum gas through a carburetor into an internal combustion engine comprising the steps of: maintaining a source of liquified petroleum gas in a pressure-temperature equilibrium where said gas is a liquid; removing said gas from said source; introducing said gas into the carburetor; reducing the pressure of said gas to a second pressure that is lower than the pressure at its source maintaining said gas as a liquid; cooling the intake manifold by vaporizing the gas in a chamber contiguous to the intake manifold and encircling the input tube of the engine; reducing the pressure of the vaporized gas to a third pressure; metering the flow of air into the intake tube of the engine; metering the vaporized gas into the intake tube of the engine, and then mixing the vaporized gas with a predetermined amount of air forming a fuel charge in the intake tube of the internal combustion engine.

Claim 10

A method for metering liquified petroleum gas through a carburetor into an internal combustion engine comprising the steps of: maintaining a source of liquified petroleum gas in a pressure-temperature equilibrium where said gas is a liquid; removing said gas from said source; introducing said gas into the carburetor; reducing the pressure of said gas to a second pressure that is lower than the pressure at its source maintaining said gas as a liquid; cooling the intake manifold by vaporizing the gas in a chamber contiguous to the intake manifold and encircling the input tube of the engine; reducing the pressure of the vaporized gas to a third pressure; metering the flow of air into the intake tube of the engine; metering the vaporized gas into the intake tube of the engine, and then mixing the vaporized gas with a predetermined amount of air forming a fuel charge in the intake tube of the internal combustion engine.