Abstract: A carburettor metering system comprises a fuel evaporator 113 consisting of porous parallel plates 114 with their lower portions immersed in fuel 121, fuel metering means 122 for supplying fuel to the evaporator 113, and a laminar flow air restrictor 128 comprising a series of parallel plates 127 separated by spacers and defining narrow gaps between the plates 127. Such an arrangement enables a substantially constant air/fuel mixture strength to be obtained over a wide range of air flow rates in single cylinder engines. Furthermore the supply of mixture to the engine by way of an exit tube 126 may be controlled by a valve member 132 coupled to the engine governor so that the rate of flow of mixture varies in dependence on the load, and additionally so as to change the system between two modes of carburettor operation, namely lean operation, which is provided up to about three quarters load, and rich operation in which additional fuel is supplied to the evaporator 113.

Abstract: A carburetor metering system is provided comprising a fuel valve including a valve member movable with respect to a valve seat to vary the fuel flow, the valve member and the valve seat having substantially parallel inclined surfaces and which define therebetween a passage for the flow of fuel having a width corresponding to the distance apart of the surfaces and a length. A wick for use a carburetor metering system is also provided for absorbing liquid for vaporization into an air flow, comprising a cloth of woven strands and means for suspending said cloth in the air flow. There is also provided a spark plug for use in a fuel combustion system.

Abstract: A carburettor metering system comprises a fuel evaporator 113 consisting of porous parallel plates 114 with their lower portions immersed in fuel 121, fuel metering means 122 for supplying fuel to the evaporator 113, and a laminar flow air restrictor 128 comprising a series of parallel plates 127 separated by spacers and defining narrow gaps between the plates 127. Such an arrangement enables a substantially constant air/fuel mixture strength to be obtained over a wide range of air flow rates in single cylinder engines. Furthermore the supply of mixture to the engine by way of an exit tube 126 may be controlled by a valve member 132 coupled to the engine governor so that the rate of flow of mixture varies in dependence on the load, and additionally so as to change the system between two modes of carburettor operation, namely lean operation, which is provided up to about three quarters load, and rich operation in which additional fuel is supplied to the evaporator 113.

Abstract: A carburetor metering system is provided comprising a fuel valve including a valve member movable with respect to a valve seat to vary the fuel flow, the valve member and the valve seat having substantially parallel inclined surfaces and which define therebetween a passage for the flow of fuel having a width corresponding to the distance apart of the surfaces and a length. A wick for use a carburetor metering system is also provided for absorbing liquid for vaporization into an air flow, comprising a cloth of woven strands and means for suspending said cloth in the air flow. There is also provided a spark plug for use in a fuel combustion system.

Abstract: A carburetor metering system is provided comprising a fuel valve including a valve member movable with respect to a valve seat to vary the fuel flow, the valve member and the valve seat having substantially parallel inclined surfaces and which define therebetween a passage for the flow of fuel having a width corresponding to the distance apart of the surfaces and a length. A wick for use a carburetor metering system is also provided for absorbing liquid for vaporization into an air flow, comprising a cloth of woven strands and means for suspending said cloth in the air flow. There is also provided a spark plug for use in a fuel combustion system.

Abstract: A fuel valve 1 is provided for injecting liquid fuel into a stream of air which comprises a valve member 2 movable along a displacement axis 3 with respect to a valve seat 4 to vary the fuel flow through the valve 1. The valve member 2 and the valve seat 4 have substantially parallel surfaces 7 and 9 which are inclined with respect to the displacement axis 3 and which define therebetween a passage for the flow of fuel having a width W corresponding to the distance apart of the surfaces 7 and 9 and a length L corresponding to the degree of overlap of the surfaces 7 and 9. The length L of the passage varies substantially in proportion to the width W as the valve member 2 is moved along the displacement axis 3. Such a valve construction minimizes the effect of momentum changes in the fuel orifice, and enables accurate control of fuel flow over a wide range of air flows and mixture strengths.

Abstract: In vaporization means for liquid fuel for an internal combustion engine, the mixture strength is measured and used to control the rate of flow of liquid fuel into the air stream so as to maintain the mixture strength constant. Measurement of mixture strength is effected by measuring the temperature drop in the air flow due to the latent heat of the liquid fuel.