An engine component, for example a piston ring, including a wear resistant coating applied by physical vapor deposition (PVD) is provided. The coating includes tetrahedral amorphous carbon (ta-C), the carbon of the coating includes sp.sup.3 hybrid orbitals, and the coating includes boron in an amount of 0.1 wt. % to 4.0 wt. %, based on the total weight of the coating. The doped boron makes the coating less sensitive to the ion energy during the physical vapor deposition (PVD) process, improves adhesion of the coating, and expected to reduce compressive stress in the coating. Thus, the boron-doped ta-C coating can be applied to a greater thickness compared to ta-C coatings without the doped boron. In addition, there is a strong indication that the addition of boron will maintain a high level of sp.sup.3 bonded carbon and a high microhardness.

An engine component, for example a piston ring, including a wear resistant coating applied by physical vapor deposition (PVD) is provided. The coating includes tetrahedral amorphous carbon (ta-C), the carbon of the coating includes sp.sup.3 hybrid orbitals, and the coating includes boron in an amount of 0.1 wt. % to 4.0 wt. %, based on the total weight of the coating. The doped boron makes the coating less sensitive to the ion energy during the physical vapor deposition (PVD) process, improves adhesion of the coating, and expected to reduce compressive stress in the coating. Thus, the boron-doped ta-C coating can be applied to a greater thickness compared to ta-C coatings without the doped boron. In addition, there is a strong indication that the addition of boron will maintain a high level of sp.sup.3 bonded carbon and a high microhardness.

Load transfer point offset of rocking journal bearings in uniflow-scavenged, opposed-piston engines with phased crankshafts includes differing offsets for the load transfer points of opposed pistons. More specifically, under the condition that a first crankshaft leads the second crankshaft, an angular offset of a rocking journal wristpin of a piston coupled to the first crankshaft proportional to an offset of the first crankshaft relative to the second crankshaft is made to ensure adequate oil film thickness to the wristpin when it experiences a peak combustion pressure during a power stroke.

Load transfer point offset of rocking journal bearings in uniflow-scavenged, opposed-piston engines with phased crankshafts includes differing offsets for the load transfer points of opposed pistons. More specifically, under the condition that a first crankshaft leads the second crankshaft, an angular offset of a rocking journal wristpin of a piston coupled to the first crankshaft proportional to an offset of the first crankshaft relative to the second crankshaft is made to ensure adequate oil film thickness to the wristpin when it experiences a peak combustion pressure during a power stroke.

An automotive shaft includes a journal having a crest-to-crest contact surface area defined by and between undercut regions of the shaft, an entirety of the crest-to-crest contact surface area being laser hardened to a depth no greater than 1 mm to form a layer that does not contain unhardened portions.

An automotive shaft includes a journal having a crest-to-crest contact surface area defined by and between undercut regions of the shaft, an entirety of the crest-to-crest contact surface area being laser hardened to a depth no greater than 1 mm to form a layer that does not contain unhardened portions.

A rotatable assembly, such as a crankshaft or camshaft assembly, includes a first rotatable component and a second rotatable component coupled to the first rotatable component. The first rotatable component includes a first body and defines a plurality of recesses extending into the first body. The second rotatable component includes a second body and defines a plurality of protrusions extending from the second body. The protrusions are disposed inside the respective recesses to allow the second rotatable component to rotate in unison with the first rotatable component.

A rotatable assembly, such as a crankshaft or camshaft assembly, includes a first rotatable component and a second rotatable component coupled to the first rotatable component. The first rotatable component includes a first body and defines a plurality of recesses extending into the first body. The second rotatable component includes a second body and defines a plurality of protrusions extending from the second body. The protrusions are disposed inside the respective recesses to allow the second rotatable component to rotate in unison with the first rotatable component.

An improved internal combustion engine utilizes at least one orbital body with at least one orbiting rod journal offset and engaged in a specific way from the center of orbiting body. Further, orbiting body together with orbiting rod journal and one of the gears as one body, rotationally linked to the block via stationary second gear engaged in 1:1 ratio. Which transfers the rotation to main journal via flying arm. Such that radial motion of flying arm transfers the rotation to the main crankshaft axis and constitute one body. This results in a constant volume compression period of max. 60° , improving operation, efficiency and cleanliness of the engine.

A biasing member assembled with a bearing and a crankshaft wherein the bearing is configured to receive the crankshaft. The crankshaft is assembled with an internal combustion engine. The biasing member biases the bearing in an axial direction relative to the crankshaft to reduce an endplay of the crankshaft while the engine is operable in a normal operating condition. The biasing member provides a resilient biasing force for biasing the bearing into engagement with a cylinder block when the crankshaft is operational to thereby eliminate or reduce the crankshaft endplay and improve the sealing performance of a crankshaft axial seal.