A moment-cancelling, four-stroke engine is disclosed. The engine includes a first cylinder having a first piston and a second cylinder having a second piston, a first crankshaft operably connected to the first piston and a second crankshaft operably connected to the second piston. The first crankshaft rotates in a first direction and the second crankshaft rotates in a second direction that is opposite the first direction to cancel the moments applied to the engine and reduce engine vibration.

A moment-cancelling, four-stroke engine is disclosed. The engine includes a first cylinder having a first piston and a second cylinder having a second piston, a first crankshaft operably connected to the first piston and a second crankshaft operably connected to the second piston. The first crankshaft rotates in a first direction and the second crankshaft rotates in a second direction that is opposite the first direction to cancel the moments applied to the engine and reduce engine vibration.

The disclosure relates to a method for operating an internal combustion engine of a watercraft, in particular on inland waters, in which (i) in an electrolysis unit for the production of hydrogen, water is split into hydrogen and oxygen, (ii) a carbon dioxide sorption unit extracts carbon dioxide from the ambient air, (iii) the hydrogen and the carbon dioxide are fed to a methanol synthesis unit for the production of methanol, and are synthesized therein to methanol, (iv) a photovoltaic unit absorbs solar energy and converts it into electrical energy. The electrolysis unit, the carbon dioxide sorption unit and the methanol synthesis unit are powered by the electrical energy generated in the photovoltaic unit. The methanol produced is transported by means of a distributor system to at least one tank of the watercraft, and is fed from the tank as required to the internal combustion engine, and therein is combusted to generate mechanical energy.

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.

A pivot bearing suitable for two connecting rods in at least one piston of an internal combustion engine having two crankshafts, includes radial bearing regions that are provided with bolt boreholes and are disposed on either side of a center longitudinal plane of the piston and delimit connecting rod ends, forming an intermediate space. The bearing regions are designed as cylinder bodies having a crucible-like cross-section, of which each cylinder body has a base wall and a bearing ring jacket. The base walls of the two cylinder bodies extend at a distance from each other, and the bearing ring jackets surrounding the base walls are guided away from the base walls in opposite directions. One or more connecting supports run between the base walls. The bearing ring jackets cooperate with the piston boreholes in a rotatably movable manner. The base walls are connected to bearing bushings which are oriented in the axial direction of the pivot bearing and into which the bolt boreholes are incorporated. The pivot bearing is made of a material that brings about a targeted low-weight construction of the pivot bearing, while offering high strength and low wear.

A pivot bearing suitable for two connecting rods in at least one piston of an internal combustion engine having two crankshafts, includes radial bearing regions that are provided with bolt boreholes and are disposed on either side of a center longitudinal plane of the piston and delimit connecting rod ends, forming an intermediate space. The bearing regions are designed as cylinder bodies having a crucible-like cross-section, of which each cylinder body has a base wall and a bearing ring jacket. The base walls of the two cylinder bodies extend at a distance from each other, and the bearing ring jackets surrounding the base walls are guided away from the base walls in opposite directions. One or more connecting supports run between the base walls. The bearing ring jackets cooperate with the piston boreholes in a rotatably movable manner. The base walls are connected to bearing bushings which are oriented in the axial direction of the pivot bearing and into which the bolt boreholes are incorporated. The pivot bearing is made of a material that brings about a targeted low-weight construction of the pivot bearing, while offering high strength and low wear.

There is disclosed an internal combustion engine. The internal combustion engine includes a cylinder unit and a piston unit. The cylinder unit is rotatably coupled to a pair of spaced-apart crankshafts, with the cylinder unit moveable along a longitudinal axis. The piston unit is continually disposed within the cylinder unit, with the piston unit rotatively coupled to a second pair of spaced-apart crankshafts. The piston is moveable along the longitudinal axis in a direction opposite the direction of the cylinder during a combustion cycle. Both the cylinder unit and the piston unit are structured to be balanced relative to the respective center-of-gravity of each unit. Each center-of-gravity is located midway between the pair of spaced-apart crankshafts to which each unit is rotatively coupled.

In an inverted V-8 engine capable of operating in power level steps with four pairs of piston and cylinder assemblies having fuel injectors with dual options, the improvement which comprises a three component frame structure having cooperating interengaging surfaces containing two banks of four inline crankshaft connected piston and cylinder units converging angularly upwardly from two interconnected crankshafts. The surface-to-surface contact between the block component and head component includes oppositely paired cylinder open ends covered by cam operated valving in the head component with the adjacent upper combustion chambers of each pair of cylinders being communicated by an intercommunicating polished passage formed in a two-piece insert fixedly positioned in a recess in the head component and a method of operating the engine in a vehicle.

In an inverted V-8 engine capable of operating in power level steps with four pairs of piston and cylinder assemblies having fuel injectors with dual options, the improvement which comprises a three component frame structure having cooperating interengaging surfaces containing two banks of four inline crankshaft connected piston and cylinder units converging angularly upwardly from two interconnected crankshafts. The surface-to-surface contact between the block component and head component includes oppositely paired cylinder open ends covered by cam operated valving in the head component with the adjacent upper combustion chambers of each pair of cylinders being communicated by an intercommunicating polished passage formed in a two-piece insert fixedly positioned in a recess in the head component and a method of operating the engine in a vehicle.