A pair of cylinders (2, 5) are arranged in parallel at the two sides of a crankshaft (8). The cylinders (2, 5) are respectively provided with pairs of pistons (3, 4, 6, 7). The crankshaft (8) has a pair of crankpins (12, 13). The axes of these crankpins (12, 13) are slanted with respect to the axis of the crankshaft (8) in opposite directions. The crankpins (12, 13) have the rocker members (14, 15) attached to them to be able to turn. The tip ends of the arms (16) of the rocker member (14, 15) are connected to the connecting rods (11) of the corresponding pistons (3, 4, 6, 7). If the pistons (3, 4, 6, 7) reciprocate the rocker members (14, 15) engage in swinging motion and the crankshaft (8) rotates.

An internal combustion engine for use with a propeller driven aircraft includes a camshaft adapted to function as an output shaft that rotates a propeller to provide propulsive thrust. A gear set is configured to transfer rotational power from the crankshaft to the camshaft and to rotate the camshaft at a velocity that is proportional to the rotational velocity of the crankshaft. The gear set is disposed rearward of the engine housing rearward wall and is configured to rotate the camshaft in a direction opposite the crankshaft rotation. The length of the camshaft reduces engine torsional vibration. In one embodiment, the engine is a six-cylinder compression ignition engine having a boxer configuration and can generate a peak output power within a range from about 300 horsepower to about 350 horsepower.

An engine provided with a combustion chamber includes a cylinder head in which a bulkhead is provided so as to extend toward the combustion chamber and an intake port is formed so as to bifurcate at the bulkhead, a bulkhead member that is provided with a partition plate intersecting the bulkhead and that divides the intake port into a first flow passage and a second flow passage with the partition plate provided between the first and second flow passages. The bulkhead of the cylinder head has a cutout formed and the partition plate of the bulkhead plate has an auxiliary wall that fills the cutout.

An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the coupling includes a connecting rod coupled to the piston, a slider bearing located for reciprocating movement relative to the connecting rod, the coupling further including a crankshaft rotatably mounted within a slider bearing, the engine having a camshaft and a balance shaft wherein the balance shaft is housed in a hollow of the camshaft such that the camshaft and the balance shaft rotate about a common axis.

An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the engine has increased engine part commonality. The internal combustion engine may include a first cylinder bank and a second cylinder bank, the first cylinder bank having a first cylinder head, the second cylinder bank having a second cylinder head, and the first cylinder head and the second cylinder head being formed as common parts such that they are interchangeable. An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the engine includes a crankcase formed of a plurality of separable like parts, each of the like parts being cast as a common part.

An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the engine has increased engine part commonality. The internal combustion engine may include a first cylinder bank and a second cylinder bank, the first cylinder bank having a first cylinder head, the second cylinder bank having a second cylinder head, and the first cylinder head and the second cylinder head being formed as common parts such that they are interchangeable. An internal combustion engine, including a piston, a cylinder, and an output shaft, wherein the piston is arranged for reciprocating motion within the cylinder, driven by combustion, and the piston is coupled to the output shaft by a coupling such that said reciprocating motion of the piston drives rotation of the output shaft, wherein the engine includes a crankcase formed of a plurality of separable like parts, each of the like parts being cast as a common part.

There is presented various embodiments disclosed in this application, including an improved crankshaft system using a load connecting member which provides a greater maximum torque angle than a conventional system, thereby improving efficiency and power.

There is presented various embodiments disclosed in this application, including an improved crankshaft system using a load connecting member which provides a greater maximum torque angle than a conventional system, thereby improving efficiency and power.

Pressurized air may be generated within a lightweight opposed piston engine without the need to make use of a supercharger. The lightweight engine may be combined with one or more lightweight micro-generators.

In some aspects, reciprocating engines can include a first reciprocating mechanism that includes an axially translating y-axis component configured to reciprocate substantially along a y-axis with a reciprocating motion of a piston assembly relative to a base to which the y-axis component is slidingly attached. The first reciprocating mechanism can include an x-axis component slidingly coupled to and translating with the y-axis component along the y-axis, the x-axis component being: i) configured to reciprocate substantially perpendicularly to the y-axis relative to the y-axis component, ii) comprising an orbital output component, and iii) comprising an orbital linking component disposed substantially concentric with the orbital output component. The first reciprocating mechanism can include a stationary output component and a stationary linking component that are substantially concentric and disposed in a direction that is substantially perpendicular to the x-y plane.