The provided is a bearing device for a crankshaft of an internal combustion engine including: a crankshaft having a plurality of journal portions; main bearings for supporting the crankshaft; and a bearing housing, wherein a range in which the oil groove of the upper-side halved bearing of the second main bearing is formed in the circumferential direction includes at least a range of a circumferential angle of 20° within the ±45° region, a circumferential end portion of the oil groove on a rotationally forward side communicates with the crush relief at a minimum, and is open to a circumferential end face at a maximum, and a circumferential end portion of the oil groove on the rotationally backward side of the journal portion is positioned on a circumferential center portion side of the upper-side halved bearing from a circumferential end face of the upper-side halved bearing.

The provided is a bearing device for a crankshaft of an internal combustion engine including: a crankshaft having a plurality of journal portions; main bearings for supporting the crankshaft; and a bearing housing, wherein a range in which the oil groove of the upper-side halved bearing of the second main bearing is formed in the circumferential direction includes at least a range of a circumferential angle of 20° within the ±45° region, a circumferential end portion of the oil groove on a rotationally forward side communicates with the crush relief at a minimum, and is open to a circumferential end face at a maximum, and a circumferential end portion of the oil groove on the rotationally backward side of the journal portion is positioned on a circumferential center portion side of the upper-side halved bearing from a circumferential end face of the upper-side halved bearing.

This invention relates to a drive system for an automatic step. Some embodiments include a rotary actuator for moving an automatic step, a crank arm pivotally coupled to the actuator and pivotable about a central shaft, and a first link pivotally coupled to the crank arm, the first link having first and second ends. The system has one or more force mitigation mechanisms capable of reducing forces eccentric with respect to the actuator. A first force mitigation mechanism engages when the step is deployed or nearly deployed by aligning the central shaft with the first and second ends of the first link along a first axis to generally place eccentric forces originating from the step against the central shaft of the crank arm instead of directly engaging the actuator. A second force mitigation mechanism allows the crank arm to yield without forcing the actuator by using a clutch adjacent to the central shaft.

According to one embodiment, a crank portion is formed from a crank piece, an element separate from a shaft portion. The crank piece includes a fitting hole in which the shaft portion is fit by predetermined “interference” and a slit-like slot with one end opened in an inner circumferential surface of the fitting hole, and an other end closed inside the crank piece. The fitting hole is deformed so as to expand its diameter when expanding a width of the slot. The shaft portion is fit in the fitting hole of the crank piece by the predetermined “interference” when inserted in the deformed fitting hole and the fitting hole restores an original form while the shaft portion is in the fitting hole.

A crankshaft includes a first oil hole, a second oil hole, and a through hole. The second oil hole extends in a direction in which the second oil hole intersects the first oil hole. A first extension is an imaginary line extending from an inner wall surface of the first oil hole on a second oil hole side. A second extension is an imaginary line extending from an inner wall surface of the second oil hole on a first oil hole side. The through hole passes through an intersection between the first extension and the second extension. At least one end of the through hole opens on an outer peripheral surface.

A crankshaft for an internal combustion engine is provided. The crankshaft comprises at least four main journals aligned on a crankshaft axis of rotation defining a centerline. The crankshaft further comprises at least three pin journals. Each pin journal is disposed about a respective pin journal axis and positioned between the main journals. Each of the pin journals is joined to a pair of crank arms. Each pair of crank arms is joined to a respective main journal. Each of the main journals, pin journals, and crank arms is made of a first metallic material. Each crank arm has an over-molded counterweight metallurgically bonded thereto. Each counterweight is disposed opposite a respective pin journal relative to the centerline for balance and stability. Each counterweight is made of a second metallic material. The crankshaft has a weight ratio of the second metallic material to the first metallic material of between 0.20 to 0.50.

A bearing support structure in which a split rolling bearing split into two in a peripheral direction is mounted on the outer periphery of a rotatable shaft member, the shaft member includes a cylindrical shaft portion, and a first side surface and a second side surface that face each other in an axial direction with the shaft portion sandwiched therebetween and that extend in a substantially radial direction, and at least one of the first side surface and the second side surface is inclined with respect to a plane orthogonal to a central axis of the shaft member.

A crankshaft (4) with a first central axis (A), has at least two main bearing journals (12), through which the first central axis (A) extends. At least one crankshaft web (10) is arranged between the main bearing journals (12), wherein the at least one crankshaft web (10) comprises two crank discs (14) connected with each other via a crankpin (16) with a second central axis (B). At least one crank disc (14) has a recess (26) with a planar bottom surface (28), wherein the recess (26) is adapted in the at least one crank disc (14) in such a way that the second central axis (B) of the crankpin (16) cuts the planar bottom surface (28). That planar bottom surface (28) is oriented at a right angle in relation to the direction of the second central axis (B) of the crankpin (16). A bore (30) with a third central axis (C) extend through the planar bottom surface (28) of the recess (26), through the at least one crank disc (14), and into the at least one crankpin (16). Also, a combustion engine (2), a vehicle (1) and a method for manufacture of a crankshaft (4) are disclosed.

The invention relates to a machine that amplifies the drive torque of a moving shaft, which is formed by at least one pair of identical units facing a central shaft, each unit being formed by at least one mechanical actuator (cam), a hydraulic actuator (amplified linear force that provides the application of Pascal's law) and a mechanism comprising a piston, connecting rod and crankshaft. For mechanical considerations, the machine is a two-stroke engine (compression and intake) having at least two opposite horizontal pistons, that is, a 180 V engine.

An eccentric member for a system for varying compression ratio of an internal combustion engine comprises two circumferential bearing portions for bearing respective big ends of connecting rods of a V-type internal combustion engine. The bearing portions are eccentric with respect to an inner surface of the eccentric member and located at a distance from each other in axial direction of the eccentric member. The eccentric member also comprises two external gears between which the bearing portions are located. The eccentric member is made of two half-sleeves which are fixed to each other at least between the bearing portions.