Retainer for tapered roller bearing, method for manufacturing retainer, and tapered roller bearing

A retainer for a tapered roller bearing, comprising:

• a first side having a first radius and a second side having a second radius, wherein the first radius is smaller than the second radius;
• a first ring portion at the first side of the retainer;
• a second ring portion at the second side of the retainer;
• a plurality of brace portions arranged between the first ring portion and the second ring portion;
• and
• a hook portion formed at the second side of the retainer, the hook portion being engaged with a second side of an inner race, the second side of the inner race having a radius that is larger than a radius of a first side of the inner race;
• wherein the retainer is made of a resin material and is configured to retain tapered rollers in pockets formed between the plurality of brace portions,
• wherein an outer diameter of each of the pockets at the first side of the retainer is larger than an inner diameter of the hook portion,
• wherein the hook portion comprises an outer end surface, a radially inner end, and a guide inclined surface extending from the outer end surface to the radially inner end so as to incline toward the first side of the retainer, and
• wherein an inclination angle of the guide inclined surface with respect to the outer end surface is within a range from 10° to 30°, and a radial length of the guide inclined surface is within a range from 20% to 40% of a radial length of the hook portion.