Abstract: Various embodiments include two-stroke stratified engines and dual passage carburetors for use with gaseous fuel, such as hydrogen, methane, liquid petroleum gas, pure propane, and butane. A stratified air-head engine and low pressure fuel injected engines with fuel only tube is included.

Abstract: An integrally cast four-stroke engine mono-block includes integrally cast cylinder block, cylinder head, and portion of a crankcase including crankcase outboard and inboard walls. At least parts of outer and inner bearing bosses are integrally cast with the cylinder block with the inner bearing boss integrally cast in the inboard wall. At least one cored out longitudinally extending open valve train chamber is disposed between the outboard wall and the cast cylinder block. An alternative embodiment of the integrally cast four-stroke engine mono-block includes at least parts of an outer bearing boss and/or an inner bearing boss integrally cast in the outboard and inboard walls respectively with the cast cylinder block. At least one cored out longitudinally extending open valve train chamber is disposed between the outboard wall and the cast cylinder block. Push tube passages or a belt drive passage may be in the valve train chamber.

Abstract: A two-stroke internal combustion engine includes at least one gaseous communication charge passage between a crankcase chamber and a combustion chamber of the engine and a piston to open and close the top end of the transfer passage. The air inlet port to the transfer passage for stratified scavenging is opened and closed by the piston that has passages and cutouts. The charge inlet to the crankcase chamber is opened and closed by the piston. The air and charge inlet passages are substantially asymmetrical to the layout of the transfer passages and are closer to one transfer passage compared to the other. The internal air passage in the piston is substantially perpendicular to the piston pin.

Abstract: A detachable power head (200) and a detachable equipment (500, 900) provided for hand held applications; such as a trimmer, blower, etc. The power head includes an internal combustion engine and a ring on the housing and a matching ring on the power equipment for easy attachment of the power head to the equipment.

Abstract: Various embodiments include two-stroke stratified engines and dual passage carburetors for use with gaseous fuel, such as hydrogen, methane, liquid petroleum gas, pure propane, and butane. A stratified air-head engine and low pressure fuel injected engines with fuel only tube is included.

Abstract: An integrally cast four-stroke engine mono-block includes integrally cast cylinder block, cylinder head, and portion of a crankcase including crankcase outboard and inboard walls. At least parts of outer and inner bearing bosses are integrally cast with the cylinder block with the inner bearing boss integrally cast in the inboard wall. At least one cored out longitudinally extending open valve train chamber is disposed between the outboard wall and the cast cylinder block. An alternative embodiment of the integrally cast four-stroke engine mono-block includes at least parts of an outer bearing boss and/or an inner bearing boss integrally cast in the outboard and inboard walls respectively with the cast cylinder block. At least one cored out longitudinally extending open valve train chamber is disposed between the outboard wall and the cast cylinder block. Push tube passages or a belt drive passage may be in the valve train chamber.

Abstract: A two-stroke internal combustion engine includes dual transfer passages in gaseous communication between a crankcase chamber and a combustion chamber of the engine, an air passage through the crankcase to the crankcase chamber and in gaseous communication with a carburetor of the engine. A rotatable circular disk or crank-web is rotatably connected to a crankshaft. A piston may be used to open and close a top end of the passages. An air inlet port to the transfer passage for stratified scavenging is opened and closed by the crank-web that has passages and cutouts. The rotary valve replaces the one-way reed valve used in stratified scavenged and charged two-stroke engines. The air passes from lower ends of the transfer passages to top ends and into the crankcase through a piston passage, through the adjacent transfer passages directly, or through a passage in the piston into the crankcase.

Abstract: A two-stroke internal combustion engine includes at least one gaseous communication charge passage between a crankcase chamber and a combustion chamber of the engine and a piston to open and close the top end of the passage and a rotary valve to open and close the lower end of the transfer passage. The air inlet port to the transfer passage for stratified scavenging is opened and closed by the crank-web that has passages and cutouts. The rotary valve replaces the one-way reed valve used in stratified scavenged and charged two-stroke engines. The air passes from the lower end of transfer passage to the top end and into the crankcase through the piston passage, alternatively air may also pass through the adjacent transfer passage directly or through a passage in the piston into the crankcase. A two-stroke engine also consists of a charge injection system controlled by the crank web eliminating the one-way valve.

Abstract: A 4-stroke engine incorporating a mono-shaft multi-valve operating system, the multi-valve operating system incorporating a first cam follower assembly that is associated with an intake valve, a second cam follower assembly that is associated with an exhaust valve, and a cam follower channel assembly that is integrated into a crank web of the engine, the cam follower channel assembly including a base circle channel, a cam channel, and a cross-over channel. The cam follower channel assembly is configured to commonly interact with the two cam follower assemblies to operate the intake valve at a first instance, and the exhaust valve at a second instance, with both instances occurring while the crank web completes two rotations. When either of the two cam follower assemblies engages with a cam channel of the cam follower channel assembly, the cam follower channel assembly is configured to provide a camming operation to operate the respective valve.

Abstract: A two stroke internal combustion engine includes at least one gaseous communication passage between a crankcase chamber and a combustion chamber of the engine. A first rotary shut-off valve on a periphery of a rotatable circular disk is operatively disposed between the passage and the crankcase chamber and rotatably connected to a crankshaft of the engine. The valve includes at least one circumferentially extending pathway extending axially at least partially through the disk and is rotatably alignable with a crankcase port of the passage though the crankcase chamber. The circumferentially extending pathway extends circumferentially less than 180 degrees. Two particular embodiments of the pathways include rectangular cross-sectional slots and annular L-shaped pathways. The gaseous communication passage may be a transfer passage or a charge injection passage or both which are controlled two or more axially adjacent rotary shut-off valves on the periphery of the disk.

Abstract: A two stroke internal combustion engine includes at least one gaseous communication passage between a crankcase chamber and a combustion chamber of the engine. A first rotary shut-off valve on a periphery of a rotatable circular disk is operatively disposed between the passage and the crankcase chamber and rotatably connected to a crankshaft of the engine. The valve includes at least one circumferentially extending pathway extending axially at least partially through the disk and is rotatably alignable with a crankcase port of the passage though the crankcase chamber. The circumferentially extending pathway extends circumferentially less than 180 degrees. Two particular embodiments of the pathways include rectangular cross-sectional slots and annular L-shaped pathways. The gaseous communication passage may be a transfer passage or a charge injection passage or both which are controlled two or more axially adjacent rotary shut-off valves on the periphery of the disk.