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 engine balance shaft (20) for an internal combustion engine (24) is provided having reduced total mass and rotational inertia while having sufficient bending stiffness and sufficient unbalance mass. The balance shaft (20) is formed by fixedly coupling a counterweight (56), a front bearing journal (68), a rear bearing journal (60), a tail piece (40), and a nose piece (44) to a hollow tube (52). The hollow tube (52) is hydroformed to expand the diameter of the tube and fasten the desired components to the tube (52).

An internal combustion engine includes a crankcase in which a crankshaft is rotatably mounted in bearings including bearing covers, to which at least one connecting rod carrying a piston is linked. The piston is movable in a cylinder covered by a cylinder head forming a combustion chamber and gas exchange valves are arranged in the cylinder head, which are actuated by at least one camshaft, which is connected to a gear train gear wheel situated on the crankshaft via a differential gear. A mass differential gear including two balance shafts is present. The mass differential gear is situated in a gear frame and attached to the crankcase below the crankshaft and driven by a mass shaft drive gear situated on the crankshaft, which is arranged axially essentially next to the gear train gear wheel/idler gear. The gear train gear wheel/idler gear is arranged on the main bearing cover.

A balance device for an internal combustion engine includes a crankshaft and a balance shaft. The crankshaft includes a CS eccentric weight. The balance shaft includes a BS eccentric weight. A CS connected point deviated from the CS main shaft, and a BS connected point deviated from the BS axial shaft are connected with a connection rod. A CS connection mechanism that enables relative rotation of the crankshaft and the connection rod is provided at the CS connected point. A BS connection mechanism that enables relative rotation of the balance shaft and the connection rod is provided at the BS connected point. A guide section guides a motion of the connection rod so that the balance shaft rotates in an opposite direction to the crankshaft.

An idle gear assembly comprises an outer ring having gear teeth formed on an external surface thereof and engaged with a crank gear and any one of the left and right balance gears. A bearing includes an inner member and an outer member in a radial direction of the bearing and a plurality of rolling bodies disposed between the inner member and the outer member. A ring has elasticity in a radial direction thereof. A hub has a flange, which is in contact with the bearing, and a penetration hole. The flange and the penetration hole are formed at one side of the hub in an axial direction. A nut is inserted through another side and mounted at a hollow portion of the ring. A bolt is inserted through the insertion hole of the bearing, the penetration hole, and the nut and fixes the bearing and the hub.

A balancer device includes a housing fixed to an internal combustion engine, a roller bearing disposed in the housing, a balancer shaft rotatably supported in the housing by the roller bearing, a balancer weight integrally mounted on the balancer shaft and rotatably accommodated in an weight accommodation room of the housing, an introduction part that introduces a lubricating oil from the outside to the inside of the weight accommodation room, and a discharge part that provides communication between the inside and the outside of the weight accommodation room and discharges the lubricating oil from the inside of the weight accommodation room, wherein herein the roller bearing is arranged to face the weight accommodation room.

A rolling-element bearing with line contact includes bearing inner and outer parts having running surfaces, and at least one rolling element is disposed between and makes line contact with the bearing inner and outer parts. A width of the outer running surface and/or a width of the inner running surface is narrower at least in a first circumferential partial region than a length of the rolling-element, and in the first partial region the bearing outer part running surface and/or the bearing inner part running surface extends obliquely to a rolling direction of the at least one rolling element.

A balance shaft includes an unbalanced shaft (3) comprising a bearing journal (8, 9), the periphery of which is merely partially cylindrical. The cylindrical partial periphery (10) of the bearing journal is oriented toward the shaft imbalance. The balance shaft also includes a needle roller cage assembly (15); and a bearing ring (13), which extends around the bearing journal, lies against the cylindrical partial periphery and forms the inner raceway of the needle roller cage assembly. The cage (27) of the needle roller cage assembly is designed to run on the end faces of the bearing ring axially on both sides by means of radially inwardly extending projections.

A balance shaft includes an unbalanced shaft (3) comprising a bearing journal (8, 9), the periphery of which is merely partially cylindrical. The cylindrical partial periphery (10) of the bearing journal is oriented toward the shaft imbalance. The balance shaft also includes a needle roller cage assembly (15); and a bearing ring (13), which extends around the bearing journal, lies against the cylindrical partial periphery and forms the inner raceway of the needle roller cage assembly. The cage (27) of the needle roller cage assembly is designed to run on the end faces of the bearing ring axially on both sides by means of radially inwardly extending projections.

An insert for a bed plate according to an embodiment of the present disclosure is coupled to a lower portion of an engine block. The insert of the bed plate includes a crankshaft seating portion disposed at a center and where a crankshaft is mounted. The insert of the bed plate also includes a ladder frame fixing portions that are disposed at opposite ends of the insert to facilitate coupling to a ladder frame. The insert of the bed plate also includes a plurality of protrusion portions that are formed on both surfaces of the insert and contact the ladder frame.