In-line internal combustion engine having a multi-joint crank drive and a single balance shaft for damping second-order inertia forces

An internal combustion engine comprising:

• a multi-joint crank drive, said multi-joint crank drive comprising a plurality of coupling members rotatably supported on crank pins of a crank shaft, and a plurality of articulation connecting rods rotatably supported on crank pins of an eccentric shaft, wherein each of the coupling member is pivotally connected to a piston connecting rod of a piston of the internal combustion engine and to one of the articulation connecting rods, wherein oscillations in the multi-joint crank drive generate second order inertia forces having force vectors acting in both a direction of vertical axis of the internal combustion engine which is perpendicular to the vertical axis;
• and a single balance shaft positioned above the crankshaft to neutralize the second order inertia forces.