A forged crankshaft assembly for an engine, and a method of manufacturing the same, has a forged crankshaft and a removable counterweight to provide access for core drilling or milling a cavity. The forged crankshaft has a pin bearing journal, a main bearing journal, a first crank arm supporting the pin bearing journal, a second crank arm supporting the pin bearing journal and connecting the pin bearing journal and the main bearing journal, and at least one milled crank arm cavity formed within at least a portion of the second crank arm. The removable counterweight extends radially outward from the first crank arm, wherein the crank arm cavity is configured to be accessible to a core drill or mill cutter only when the removable counterweight is removed from the first crank arm and inaccessible to the core drill or mill cutter when the removable counterweight is coupled to the first crank arm.

A forged crankshaft assembly for an engine, and a method of manufacturing the same, has a forged crankshaft and a removable counterweight to provide access for core drilling or milling a cavity. The forged crankshaft has a pin bearing journal, a main bearing journal, a first crank arm supporting the pin bearing journal, a second crank arm supporting the pin bearing journal and connecting the pin bearing journal and the main bearing journal, and at least one milled crank arm cavity formed within at least a portion of the second crank arm. The removable counterweight extends radially outward from the first crank arm, wherein the crank arm cavity is configured to be accessible to a core drill or mill cutter only when the removable counterweight is removed from the first crank arm and inaccessible to the core drill or mill cutter when the removable counterweight is coupled to the first crank arm.

A vehicle includes, an engine including a crankshaft, a crankcase which is configured to accommodate the crankshaft therein, and a centrifugal clutch which is arranged coaxially with the crankshaft, and a propeller shaft to which rotational power output from the engine and changed in speed is transmitted, the propeller shaft passing through the crankcase and intersecting the crankshaft in plan view, at least a part of the propeller shaft being located between the centrifugal clutch and a support wall portion of the crankcase configured to support the crankshaft and above a lower end of the centrifugal clutch.

A modular crankshaft configured for use within a power end assembly. The modular crankshaft is configured to interconnect a drive shaft and a plurality of linear drive assemblies. The various embodiments of modular crankshafts disclosed herein are assembled by interconnecting a plurality of individual main bearing journals using a plurality of fasteners. One or more embodiments of modular crankshafts may also include individual connecting rod journals that are attached to individual main bearing journals using a plurality of fasteners.

A modular crankshaft configured for use within a power end assembly. The modular crankshaft is configured to interconnect a drive shaft and a plurality of linear drive assemblies. The various embodiments of modular crankshafts disclosed herein are assembled by interconnecting a plurality of individual main bearing journals using a plurality of fasteners. One or more embodiments of modular crankshafts may also include individual connecting rod journals that are attached to individual main bearing journals using a plurality of fasteners.

The present invention relates to a combustion engine which includes at least one crankshaft rotating about a first rotation shaft; at least one output shaft outputting an engine torque, said output shaft rotating about a second rotation shaft separate from said first rotation shaft; at least one transmission assembly rotating about said first rotation shaft and being rotated by said crankshaft in order to transmit said engine torque to said output shaft.

According to one embodiment, a drive device includes a first piston reciprocatively along a first direction within a first mount plane, a first crankshaft orthogonal to the first mount plane, a first XY separation crank mechanism between the first piston and the first crankshaft, which converts reciprocating motion of the first piston and rotary motion of the first crankshaft into each other, a second piston reciprocatively along a second direction symmetrical to the first direction within a second mount plane symmetrical to the first mount plane about a central reference plane, a second crankshaft orthogonal to the second mount plane, a second XY separation crank mechanism between the second piston and the second crankshaft, which converts reciprocating motion of the second piston and rotary motion of the second crankshaft into each other, and a coupler-synchronizing mechanism which rotates the first and second crankshafts in synchronous with each other.

According to one embodiment, a drive device includes a first piston reciprocatively along a first direction within a first mount plane, a first crankshaft orthogonal to the first mount plane, a first XY separation crank mechanism between the first piston and the first crankshaft, which converts reciprocating motion of the first piston and rotary motion of the first crankshaft into each other, a second piston reciprocatively along a second direction symmetrical to the first direction within a second mount plane symmetrical to the first mount plane about a central reference plane, a second crankshaft orthogonal to the second mount plane, a second XY separation crank mechanism between the second piston and the second crankshaft, which converts reciprocating motion of the second piston and rotary motion of the second crankshaft into each other, and a coupler-synchronizing mechanism which rotates the first and second crankshafts in synchronous with each other.

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.

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.