An internal combustion engine having an improved oil treatment system. The internal combustion engine may be a splash lubrication engine in which oil is flowed through an oil circulation circuit by a passive pump. In another aspect, a dipstick tube may be provided that includes a portion of the oil circulation circuit. In a further aspect, the internal combustion engine comprises one or more protuberances that automatically penetrate an oil treatment apparatus upon the oil treatment apparatus being mounted to the internal combustion engine, thereby fluidly coupling the oil treatment apparatus to the oil circulation circuit.

An internal combustion engine having an improved oil treatment system. The internal combustion engine may be a splash lubrication engine in which oil is flowed through an oil circulation circuit by a passive pump. In another aspect, a dipstick tube may be provided that includes a portion of the oil circulation circuit. In a further aspect, the internal combustion engine comprises one or more protuberances that automatically penetrate an oil treatment apparatus upon the oil treatment apparatus being mounted to the internal combustion engine, thereby fluidly coupling the oil treatment apparatus to the oil circulation circuit.

Methods and systems are provided for a lubricant distribution assembly comprising a rotating component with a recessed circumferentially surrounded by a radially outer section, the radially inners side of which forms a surface of an undercut groove. The lubricant distribution assembly further includes a lubricant sump separated from the rotating component by a wall, a hollow tube that delivers lubricant from the lubricant sump to the lubricant distribution assembly and a lubricant deflector positioned within an upper portion of the lubricant distribution assembly and which lies in a plane that is parallel to a first axial side of the rotating component.

This invention has two main embodiments. An opposed piston 2-stroke axial engine and a 4-stroke axial engine. The opposed piston two stroke also offers an option of a novel cylinder deactivation design. Both, two stroke and four stroke engines share novel systems for coupling piston reciprocation to shaft rotation, piston and piston ring lubricant distribution, and provision for reacting out piston side load with minimum mechanical friction.

This invention has two main embodiments. An opposed piston 2-stroke axial engine and a 4-stroke axial engine. The opposed piston two stroke also offers an option of a novel cylinder deactivation design. Both, two stroke and four stroke engines share novel systems for coupling piston reciprocation to shaft rotation, piston and piston ring lubricant distribution, and provision for reacting out piston side load with minimum mechanical friction.

The present utility model discloses a portable four-stroke engine, comprising: an engine body, a flywheel and an oil storage tank, wherein an air valve distribution chamber and a crank shaft chamber are arranged in the engine; a crank shaft is arranged in the crank shaft chamber, and is connected to the flywheel; the oil storage tank is arranged on the engine body, located above the flywheel, and configured to store lubricating oil; a cam and a rocker arm mechanism are arranged in the air valve distribution chamber; and the cam is configured to drive the rocker arm mechanism. The portable four-stroke engine provided by the present utility model has a small volume and therefore has better operation performance.

A sawmill includes a four-stroke internal combustion engine having an output shaft for driving a sawblade. The output shaft has a longitudinal axis. The engine is mounted on the sawmill for rotation between a first operative position with the longitudinal axis of the output shaft extending at a first angle, and a second operative position with the longitudinal axis of the output shaft extending at a second angle transversely to the first angle. The engine has fuel injection to facilitate operation in the first and second operative positions and a lubrication system incorporating a wet sump. An oil pick up for the lubrication system is configured to pick up oil from the wet sump at both the first and second operative positions.

A sawmill includes a four-stroke internal combustion engine having an output shaft for driving a sawblade. The output shaft has a longitudinal axis. The engine is mounted on the sawmill for rotation between a first operative position with the longitudinal axis of the output shaft extending at a first angle, and a second operative position with the longitudinal axis of the output shaft extending at a second angle transversely to the first angle. The engine has fuel injection to facilitate operation in the first and second operative positions and a lubrication system incorporating a wet sump. An oil pick up for the lubrication system is configured to pick up oil from the wet sump at both the first and second operative positions.

The overhead camshaft engine (10) includes a cylinder block (11), a crankcase (12) attached to a lower part of the cylinder block to define a crankcase chamber (32), a bearing retaining member (60) attached to a part of the cylinder block, a crankshaft (20) rotatably supported by a pair of bearings (21, 22) supported by the cylinder block and the bearing retaining member, respectively, and a crankshaft pulley (53) attached to a part of the end of the crankshaft projecting outward from the bearing supported by the bearing retaining member.

The overhead camshaft engine (10) includes a cylinder block (11), a crankcase (12) attached to a lower part of the cylinder block to define a crankcase chamber (32), a bearing retaining member (60) attached to a part of the cylinder block, a crankshaft (20) rotatably supported by a pair of bearings (21, 22) supported by the cylinder block and the bearing retaining member, respectively, and a crankshaft pulley (53) attached to a part of the end of the crankshaft projecting outward from the bearing supported by the bearing retaining member.