Patent ID: 7484894
Filing Date: 2009-02-03
Classification: C21D,F16C

Abstract:
1. A tapered roller bearing comprising: an outer ring that is made of steel material and includes a crowned raceway surface; an inner ring that is made of steel material and includes a crowned raceway surface; a plurality of tapered rollers that are made of steel material, include crowned rolling contact surfaces and are interposed between the outer ring and the inner ring; and a cage for the tapered rollers, wherein surface hardnesses of the raceway surface of the inner ring and the rolling contact surfaces of the tapered rollers are 63 to 69HRC, respectively, a total crowning amount, which is a sum of outer ring crowning amount, inner ring crowning amount and two times of roller crowning amount, is 50 μm or larger, an outer ring crowning rate, which is a rate of the outer ring crowning amount on the total crowning amount, is 40% or larger, and a roller crowning rate, which is a rate of two times of the roller crowning amount on the total crowning amount is 20% or smaller.