Patent ID: 8555828

Claim:
An internal combustion engine which includes an engine body having at least one cylinder having a first cylinder end and an opposed, second cylinder end; a piston which is sealingly mounted for slidingly movement inside the cylinder and which includes a first piston end and an opposed, second piston end; and a crankshaft assembly which is connected to the piston; the piston having a piston body and including a piston valve which is mounted to a passage which extends through the piston body; the piston body includes a biasing member in the form of a compression spring which operates inside the passage thereby causing the piston valve to be biased towards a closed position; the passage includes at least one pair of strut members which support the piston valve through a valve stem thereof thereby to guide longitudinal movement of the piston valve to and from the closed position at which the passage is sealed by the piston valve; wherein first and second cylinder ends are sealed with the crankshaft assembly positioned outside of the sealed cylinder thereby forming a first chamber inside the sealed cylinder between the piston and the first cylinder end and a second chamber inside the sealed cylinder between the piston and the second cylinder end so that the crankshaft assembly is positioned outside the first and second chambers; wherein movement of the piston towards the first cylinder end causes the first chamber to become pressurised and movement of the piston to the second cylinder end causes the second chamber to become pressurised; wherein the piston is connected to the crankshaft assembly through the sealed second cylinder end thereby allowing for linear movement of the piston between the first and second cylinder ends to cause rotational movement in the crankshaft assembly; wherein rotational movement of the crankshaft assembly causes the piston valve to move to and from the closed position thereby allowing pressure formed in the second chamber through movement of the piston to ventilate the first chamber.