Split-type sliding bearing for crankshaft in internal combustion engine and split-type sliding bearing device

A split-type sliding bearing device for a crankshaft in an internal combustion engine, comprising:

• a split-type sliding bearing for a crankshaft in an internal combustion engine, comprised of a pair of semi-cylindrical bearings which are mated with each other into a cylindrical body in use, and
• a split-type bearing housing having a cylindrical bearing retaining bore which is bi-split so as to be aligned with the pair of semi-cylindrical bearings in the mated condition, for accommodating and retaining the pair of semi-cylindrical bearings in the bearing retaining bore, characterized in that
• the split-type bearing housing is comprised of a housing half having a relatively high thermal expansion coefficient, and a housing half having a relatively low thermal expansion coefficient,
• a first semi-cylindrical bearing which is one of the pair of semi-cylindrical bearings, and which is supported on the housing half having a relatively high thermal expansion coefficient, and a second semi-cylindrical bearing which is the other one of the pair of semi-cylindrical bearings, and which is supported on the housing half having a relatively low expansion coefficient, have the following dimensional relationship in a preinstalled condition:
• (1) the first and second semi-cylindrical bearings have an equal outer diameter, and
• (2) opposite circumferential end parts of the first semi-cylindrical bearing have a thickness which is larger than that of the opposite circumferential end parts of the second semi-cylindrical bearing;
• whereby the inner surfaces of the first and second bearings are aligned with each other at the abutting end faces of both semi-cylindrical bearings even though a stepped difference is caused between the abutting end faces of the pair of housing halves due to a difference between degrees of thermal expansion of both housing halves, when the temperature of the housing halves are increased during operation of the internal combustion engine in the condition that the pair of housing halves are mated with each other by fastening bolts after the first and second semi-cylindrical bearings are incorporated between the pair of housing halves.