US Patent 7841773 Tapered roller bearing

A tapered roller bearing comprises an inner ring having a conical surface-like raceway surface in it outer periphery and formed with a cone back face rib and a cone front face rib on the opposite sides of the raceway, an outer ring having a conical surface-like raceway in its inner periphery, a plurality of tapered rollers interposed between the raceways of the inner and outer rings, and a cage for holding the tapered rollers in predetermined circumferential intervals, wherein the ratio R/RBASE of the radius of curvature R of the large end face (32) of the tapered roller (30) to the distance RBASE from the apex of cone of the tapered roller (30) to the cone back face rib surface (18) of the inner ring (10) is set at 0.75 to 0.87, and the end face deflection of the large end face (32) of the tapered roller (30) is 3 μm or less.