Split-type sliding bearing for a crankshaft in internal combustion engine and split-type sliding 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, the semi-cylindrical bearings being 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 therein,
• wherein the split-type bearing housing is comprised of a housing half having a higher thermal expansion coefficient, and a housing half having a lower thermal expansion coefficient, and
• wherein the pair of semi-cylindrical bearings includes a first and second semi-cylindrical bearings, the first semi-cylindrical bearing being supported on the housing half having a higher thermal expansion coefficient, and a second semi-cylindrical bearing being supported on the housing half having a lower thermal expansion coefficient, the first and second semi-cylindrical bearings having the following dimensional relationship in a preinstalled condition:
• (a) the first and second semi-cylindrical bearings have an equal outer diameter, and
• (b) the first semi-cylindrical bearing has circumferential ends having a thickness smaller than that of the opposite circumferential ends of the second semi-cylindrical bearing,
• whereby the inner surfaces of the first and second semi-cylindrical bearings are aligned with each other at the circumferential end faces thereof even though a stepped difference is caused due to a difference in thermal contraction between the housing halves, because of a difference between thermal expansion coefficients, at the diameter of the bearing retaining bore between the circumferential end faces of the pair of housing halves when the internal combustion engine in a low temperature condition is started in a cold district 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 fitted therebetween.