Internal combustion engine fuel injection system

Claim 1

In an internal combustion engine having at least one cylinder defining a piston chamber, a compression piston reciprocable axially of said chamber, and a cylinder head cooperating with said compression piston while adjacent one end of its stroke to define therewith a combustion chamber wherein air is compressed by said compression piston while moving toward said end of its stroke; a fuel injection system comprising the combination of: pressurizing means adjacent said combustion chamber having a compression chamber and a compression means operative to further compress in said compression chamber a relativey small part of the air precompressed by said compression piston in said combustion chamber to a substantially higher pressure and temperature than the peak pressure and temperature of air compressed by said compression piston in said combustion chamber; fuel feed means including a fuel metering piston coaxial with and internal to said compression piston, said fuel metering piston and said compression piston constrained for relative movement with respect to one another, said fuel metering piston independently movable, said compression piston moved only by movement of said fuel metering piston, said fuel feed means operative only after initiation of compressive action of said compression means to supply a metered quantity of combustible fuel to said compressed body of air in said compression chamber; and nozzle means communicating said compression chamber with said combustion chamber and operative to confine at least most of the air in said compression chamber during said further compression thereof and to discharge said confined compressed air mixed with said fuel as a jet into said combustion chamber.