Patent ID: 8753019

Claim:
A turning bearing comprising: an outer ring provided on an inside circular surface thereof with an outside grooved race, an inner ring provided on an outside circular surface thereof with an inside grooved race in opposition to the outside grooved race of the outer ring, a plurality of rollers lying in a raceway defined between the outside grooved race and the inside grooved race to circulate through the raceway while bearing a load as the outer ring and the inner ring rotate relative to each other, a plurality of separators lying in the raceway in an arrangement interposed between the rollers adjoining each other, and a closure closing a loading hole provided in either of the outer ring and the inner ring for charging the raceway with the rollers and the separators, wherein the separator has a substantially quadrilateral in a transverse cross-section perpendicular to a traveling direction of the separator of which a peripheral surface is in opposition to the outer ring and the inner ring, wherein the separator has a leading side and a trailing side each of which is concaved to fit over a circular rolling surface of the roller to thereby provide concave surfaces lying either in parallel with and in-perpendicular to an axis of the roller, the concave surfaces being combined together in a crisscrossed relation, the separator having a through-hole extending across the separator at centers of the leading and trailing sides, and wherein the concave surfaces in the separator are contoured in arced or curved profiles in which the concave surfaces bulge or rise gradually towards a circular edge of the through-hole to form arcing bulges at bottoms of the concave surfaces lying in the crisscrossed relation with each other.