Free piston engine fuel feeding apparatus

Abstract

A two-cycle free piston engine which is adapted to burn various types of fuel but is particularly adapted to burn gaseous fuel. It introduces the fuel through at least one hole in the side wall of at least one cylinder at a location inwardly of the cylinder air intake and exhaust ports so as to be closed by the power piston at a time or position before the compression pressure in the power cylinder is equal to the injection pressure and also not before the valving system has interrupted the fuel flow. This advantageously keeps the fuel admission controls out of the hottest portion of the cylinder's combustion chamber, gives safer and better mixing of fuel and air and prevents blow back of fuel in the fuel supply line. The fuel admission is preferably started shortly before or after the air intake port is closed, but before the exhaust port is closed and not earlier than is sufficient to prevent the first fuel particles entering the cylinder from escaping through the exhaust port. The fuel flow is under the control of a valve that moves simultaneously with the piston and is open during a portion of the compression stroke of the piston and is closed during the power stroke thereof.