The weight of the first and fifth counterweights, which are located at opposite ends of a crankshaft, are set to be equal to or smaller than the weight of the remaining second to fourth counterweights. In addition, the thickness of the first and fifth counterweights are set to be equal to or smaller than the thickness of the remaining second to fourth counterweights. Moreover, the first to fifth counterweights are formed generally the same in configuration.

A crankshaft equipped in an engine, including an oil passage through which oil is drawn from a crank journal to a crank pin. The oil passage has an inlet formed at a peripheral region of the crank journal. When a plane including a center axis of the crank journal and a center axis of the crank pin crosses a peripheral surface of the crank journal at two cross portions, the inlet is located to be spaced apart in an opposite direction to a rotational direction of the crank journal from a journal s...

A crankshaft supporter having a support member which is attached to a cylinder block of an engine so as to support a crankshaft and which is formed of an aluminum alloy matrix with a preform cast inside. The support member includes a mounting surface, bolt holes and a dowel hole. A penetrated section of the preform has a through hole defining the bolt hole. The support member has a recess section formed of the matrix. The recess section is positioned between the mounting surface of the support m...

For a crankshaft of a motor with two outputs, which are braced against each other on a common shaft section by means of an essentially axial directed bracing force, measures are suggested, which deflect the axially directed bracing force into a bracing force with a radial component, that acts on at least one output.

A crankpin 1 of a crankshaft rotatably supports a big end of a connecting rod 4 through a sliding bearing 5 fitted therein. The sectional profile of the crankpin 1 takes the form of a polygon whose profile is made of plural arcs of curvature. When the crankpin 1 rotates relative to the bearing 5, the wedge effect is generated to decrease the squeeze loss, a kind of the power loss. And, the oil film thickness between the crankpin 1 and the bearing 5 is secured to prevent the shear loss, another k...

A crankshaft being integrated with stemmed, inertia-forced lobes that increase engine and motor efficiency, in which a respective lobe extends and branches out to a single traversal side of crankshaft integration, and thus being right-angular to its integration. Essentially, the lobe is a structurally-curved limb having respective curvature about the traversal axis of crankshaft rotation. Hence, the ensuing inertia from the lobes actually rotate. in the same direction and in parallel with the cr...

A crankshaft assembly for an internal combustion engine having a one-piece elongated shaft adapted to rotate about a longitudinal axis. The shaft includes a radially offset portion between the ends of the shaft, and this radially offset portion is spaced axially inwardly from each end of the shaft. An elongated connecting rod having a one-piece annular bearing support at one end is secured to the shaft so that the annular bearing support is positioned around the shaft offset portion. A first cou...

A crankshaft supporter having a bearing holder molded in aluminum alloy and having a bearing for supporting a crankshaft. A preform member is cast inside of the aluminum alloy. A screw hole having one opened end is formed in an outer surface of the bearing holder. A concave recess section is formed in the preform member to accommodate a bottom of the screw hole. An introduction passage is provided in the recess section to introduce molten metal therein during casting to prevent blowholes.

In a bearing metal fitted to a journal bearing portion where a center of a bearing metal fitting hole is deviated from a reference straight line in a direction orthogonal to the reference straight line at a time of mounting a cylinder head, a thickness, in a direction parallel to a direction in which the center of the bearing metal fitting hole is deviated, of one of an upper metal and a lower metal, which is positioned in the same direction as the direction in which the center of the bearing me...

A rolling bearing for mounting a crankshaft (1) in a crankcase (6) of an internal combustion engine comprising a bearing housing (4), between which housing (4) and a journal of the crankshaft (1), rolling elements (18) roll on raceways (19), the bearing housing (4) being split radially into two semi-shells (7,8) which can be connected to each other by screws (11), characterized in that a radially outer rolling element raceway (19) is formed directly on the semi-shells (7,8) and an outer peripher...