Four-cylinder machine of the reciprocating piston type having balancing

Abstract

A four-cylinder, reciprocating piston-machine includes a crankshaft having a rotary axis; a center bearing supporting the crankshaft; two outer bearings flanking the center bearing and supporting the crankshaft; and first, second, third and fourth torsion springs extending parallel to the crankshaft axis. The first and second torsion springs are parallel to and facing a first side of a reference plane containing the crankshaft axis, while the third and fourth torsion springs are parallel to and facing a second side of the reference plane. First, second, third and fourth elongated balancing masses are secured to and extending unidirectionally from respective first, second, third and fourth torsion springs toward the crankshaft in a perpendicular orientation to the crankshaft axis. The first and second balancing masses are situated at the outer bearings, while the third and fourth balancing masses are situated at the center bearing. First, second, third and fourth control cams are keyed to the crankshaft and are in engagement with the respective first, second, third and fourth balancing masses for oscillating the balancing masses toward and away from the crankshaft axis to exert varying torques to the respective torsion springs.