Patent ID: 7032548

Claim:
A free piston engine comprising: an energy generation and control assembly having a first side; a first combustion cylinder assembly located adjacent to the first side of the energy generation and control assembly and including a first cylinder liner that defines a generally cylindrical first engine cylinder, which is centered about an axis of motion; an outer piston assembly having a first outer piston located and telescopically slidable within the first engine cylinder along the axis of motion and having a first outer piston head facing the energy generation and control assembly, with the first outer piston including a first piston bridge portion located on an opposed end of the first outer piston from the first outer piston head, with the first piston bridge portion including a first rod boss and a guide post boss, which includes a cylindrical bore therethrough that extends parallel to the axis of motion, and a first rod mounted to the first rod boss and operatively engaging the energy generation and control assembly; and a first guide post extending parallel to the axis of motion and fixed relative to the first cylinder liner, and having an outer surface that is located and telescopically slidable within the bore of the first piston bridge portion to thereby align the first outer piston relative to the first cylinder liner.