Rolling bearing

A rolling bearing, comprising:

• an inner race and an outer race, which rotate relative to each other;
• a plurality of rolling elements, which are interposed between the inner race and the outer race;
• a retainer, which is arranged between the inner race and the outer race, for retaining the plurality of rolling elements equiangularly, the retainer comprising two annular members which face each other in an axial direction and have opposing surfaces each including hemispherical pockets formed in a plurality of circumferential positions, for receiving the plurality of rolling elements, the two annular members being coupled together so that the opposing surfaces are brought into abutment on each other;
• a flange portion, which extends radially and is provided on at least one of a radially inner side and a radially outer side of an axial end portion of each of the two annular members;
• and
• a recessed groove, which is formed in a region of the inner race corresponding to the flange portion or a region of the outer race corresponding to the flange portion so as to form a labyrinth together with the flange portion,
• wherein the retainer further comprises:
• a radially-outer-side protrusion, which is formed through axially extending a radially outer side of a circumferential end portion of each of the hemispherical pockets of one of the two annular members, the radially-outer-side protrusion having an inner peripheral surface capable of being held in contact with one of the plurality of rolling elements;
• a radially-inner-side recess, which is formed through recessing a radially inner side of the circumferential end portion of the each of the hemispherical pockets of the one of the two annular members;
• a radially-inner-side protrusion, which is formed through axially extending a radially inner side of a circumferential end portion of each of the hemispherical pockets of another one of the two annular members, the radially-inner-side protrusion having an inner peripheral surface capable of being held in contact with the one of the plurality of rolling elements;
• and
• a radially-outer-side recess, which is formed through recessing a radially outer side of the circumferential end portion of the each of the hemispherical pockets of the another one of the two annular members,
• wherein the radially-outer-side protrusion and the radially-inner-side protrusion are engaged with each other in the axial direction so that the radially-outer-side protrusion is inserted into the radially-outer-side recess and the radially-inner-side protrusion is inserted into the radially-inner-side recess,
• wherein the radially-outer-side protrusion and the radially-inner-side protrusion each have an engaging surface, and the engaging surfaces are inclined with respect to the axial direction so that a distal end side of each of the radially-outer-side protrusion and the radially-inner-side protrusion is thicker than a proximal end side thereof, and
• wherein the proximal end side of the radially-inner-side protrusion is thicker than the proximal end side of the radially-outer-side protrusion.