Crankshaft main bearing failure in variable compression ratio engines
having eccentric main bearing supports is prevented by supporting the
bearings in a crankshaft cradle (16) having a high stiffness and a high
natural frequency. The crankshaft cradle (16) is rotatable mounted in the
engine on a first axis, and the crankshaft (8) is mounted in the
crankshaft cradle (16) on a second axis off-set from the first axis, the
first axis and the second axis defining a first plane. The crankshaft
cradle comprises a primary eccentric member (24) and a plurality of
smaller bearing caps (26) separated by a parting line. The crankshaft
cradle comprises accentric members (24) that support the bearing element
(64), and structural webbing (72) that rigidly holds the eccentric members
(24) in alignment with one another at all times.