Patent ID: 6966280

Claim:
A method for starting a free piston internal combustion engine that includes a first pair of mutually connected pistons, a second pair of mutually connected pistons, a first piston of each pair located in a first cylinder, a second piston of each pair located in a second cylinder, the method comprising the steps of: supplying an air charge to a closed space in the cylinders; reciprocating the pistons and cyclically increasing a pressure of an air charge during successive cycles to a predetermined magnitude; cyclically admitting air and fuel to the first cylinder to produce repetitively a fuel-air mixture in the first cylinder; producing cyclic combustion of the mixture in the first cylinder; delaying application of at least a portion of an external load on the engine; cyclically admitting air and fuel to the second cylinder to repetitively produce a fuel-air mixture in the second cylinder; and producing cyclic combustion of the mixture in the second cylinder.