A reciprocating internal combustion engine includes at least one piston, which is operatively connected by two connecting rods having two crankshafts rotating in opposite directions and running parallel to each other, which crankshafts are oriented in an upright manner to a horizontal water line of a boat, and an internal combustion engine housing of the internal combustion engine is composed of at least a cylinder crank housing and a cylinder head, having inlet and outlet valves, and is bounded by an upper end face and a bottom end face. To optimize the internal combustion engine, a joint ventilation system has an oil separating device provided with an oil pre-separator and a main oil separator, via which, when operating the internal combustion engine, a mixture of oil and leaking gas, resulting in a crankcase of the cylinder crank housing, reaches, by way of a discharge line extending adjacent to the upper end face, the oil pre-separator, from where the mixture of oil and leaking gas is led into the main oil separator and there is separated into the components of oil and leaking gas. The oil flows into an oil pan connecting at the bottom end face and the leaking gas near the upper end face flows into an intake system of the internal combustion engine.

A valve operating apparatus for use in an internal combustion engine includes an intake cam 38, an intake rocker arm 33 rotatable about a rotational shaft 35 and driven by the intake cam 38, and an intake valve 40 pushed by a pusher 70 of the intake rocker arm 33, the internal combustion engine has a cylinder assembly 12L lying horizontally, and the intake rocker arm 33 has a weight 67 adjusting the center of gravity of the rocker arm 33 to position the pusher 70 above the rotational shaft 35 while the intake cam 38 is held out of abutting contact with the intake rocker arm 33.

An air cleaner system that potentially reduces debris entering a prime mover (e.g., engine) during removal/replacement of an air cleaner. In one embodiment, the engine includes a shroud defining an air cleaner compartment. The engine further includes a tubular air feed port defining a combustion air intake. The air feed port terminates at an end face located at or within the air cleaner compartment, and a lower portion of the end face is notched relative to other portions of the end face. In other embodiments, an engine oil drain system is provided that selectively positions a distal end of an oil drain tube at a drain position located away from the engine. The oil drain tube may also be repositioned to a stored position, wherein the distal end of the drain tube attaches to a nipple connected to either an engine housing or surrounding structure.

An air cleaner system that potentially reduces debris entering a prime mover (e.g., engine) during removal/replacement of an air cleaner. In one embodiment, the engine includes a shroud defining an air cleaner compartment. The engine further includes a tubular air feed port defining a combustion air intake. The air feed port terminates at an end face located at or within the air cleaner compartment, and a lower portion of the end face is notched relative to other portions of the end face. In other embodiments, an engine oil drain system is provided that selectively positions a distal end of an oil drain tube at a drain position located away from the engine. The oil drain tube may also be repositioned to a stored position, wherein the distal end of the drain tube attaches to a nipple connected to either an engine housing or surrounding structure.

Implementations are disclosed herein that relate to a cylinder occupying structure. An example provides a cylinder system comprising a mechanical cylinder including an internal space in which a fluid is introduced, and a piston configured for reciprocating motion in the internal space, and a cylinder occupying structure including an insertion rod acting as a second piston, wherein the insertion rod is variably inserted into, and retracted from, the internal space of the cylinder in correspondence with the reciprocating motion of the piston and where parts of the insertion rod and the piston may surround the combustion space, and where fluid compression and fluid combustion is conducted within separate spaces.

An eccentric sleeve for a crankshaft of a compressor, a crankshaft, a crankshaft assembly, and a compressor are provided. The crankshaft has a main shaft, a counterbalance and an eccentric shaft. The main shaft and the eccentric shaft are provided at two sides of the counterbalance and arranged eccentrically. The main shaft is internally provided with a main lubrication oil passage. An outer circumferential wall of the eccentric shaft is provided with an oil leakage hole in fluid communication with the main lubrication oil passage. The eccentric sleeve is fitted over the eccentric shaft. An outer circumferential wall of the eccentric sleeve is provided with a shaft flow hole extending through the outer circumferential wall in a thickness direction of the eccentric sleeve.

An air-cooled internal combustion engine including a crankshaft rotating about a crankshaft axis, a first cylinder having a first cylinder head, a second cylinder having a second cylinder head, and a blower assembly. The blower assembly includes a blower housing, a first fan, and a second fan. The first fan is positioned proximate the first cylinder and the second fan is positioned proximate the second cylinder.

An embodiment relates to a machine including a prime mover, a drive pulley, a chassis, a subframe, a drive device, a drive belt, and a pulley arrangement. The drive pulley is coupled to the prime mover. The chassis is configured to support at least an operator and the prime mover. The subframe is pivotally coupled to the chassis about a pivot axis. The subframe is further coupled to the chassis via a suspension device. The drive device is configured to drive wheels of the machine. The drive device is configured to be driven by the prime mover. The pulley arrangement is configured to direct the drive belt from the drive pulley to a driven pulley on the drive device. The pulley arrangement comprises at least one idler pulley having a diameter and a rotational axis.

An internal combustion may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in the cylinder in a work stroke from one end to another. The work stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion, and a compression stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.

The present disclosure provides a six-cylinder opposed free piston internal combustion engine generator. The generator comprises two free piston internal combustion engine sets, one opposed piston internal combustion engine set and two linear generator sets. Air entering cylinders is subjected to first-stage compression in low-pressure cylinder sets in the free piston internal combustion engine sets and the opposed piston internal combustion engine set and then subjected to second-stage compression in high-pressure cylinder sets, and a high pressure gas produced after the combustion is subjected to first-stage expansion in the high-pressure cylinder sets and then subjected to second-stage expansion in the low-pressure cylinder sets. The technical problem about how to improve the power generation efficiency of the opposed free piston generator and improve the reliability of the device is solved, the six-cylinder opposed free piston internal combustion engine generator is provided, a dual piston dual cylinder type free-piston internal combustion engine linear generator is used for replacing a return device in the opposed free piston generator, and the reliability and the power generation efficiency of the device are improved.