Tapered roller bearing and manufacturing method for tapered roller bearing

A tapered roller bearing comprising:

• an outer ring having an outer ring raceway surface on an inner circumferential surface thereof;
• an inner ring having an inner ring raceway surface on an outer circumferential surface thereof;
• a plurality of tapered rollers that are rollingly arranged between the outer ring raceway surface and the inner ring raceway surface;
• and
• a cage formed in a shape in which a large diameter ring part and a small diameter ring part separated in an axial direction are connected by a plurality of pillar parts that are in sliding contact with outer circumferential surfaces of the tapered rollers, and having a plurality of pockets that house and retain the tapered rollers,
• the inner ring including a large diameter-side end and a small diameter-side end, and only the large diameter-side end being formed with a flange part, wherein:
• the neighboring pillar parts constitute a first engagement allowance in which an inner diameter-side opening width of each of the pockets becomes smaller than a roller diameter at a position of the opening width in a direction of a rotation axis of each of the tapered rollers at at least a part of an inner diameter side of each of the pockets,
• the neighboring pillar parts constitute a second engagement allowance in which an outer diameter-side opening width of each of the pockets becomes smaller than the roller diameter at a position of the opening width in the direction of the rotation axis of each of the tapered rollers at at least a part of an outer diameter side of each of the pockets;
• bumps are formed on an inner surface of the small diameter ring part in the pockets;
• and
• end faces of the tapered rollers facing the bumps are substantially flat surfaces.

A tapered roller bearing comprising:

• an outer ring having an outer ring raceway surface on an inner circumferential surface thereof;
• an inner ring having an inner ring raceway surface on an outer circumferential surface thereof;
• a plurality of tapered rollers that are rollingly arranged between the outer ring raceway surface and the inner ring raceway surface;
• and
• a cage formed in a shape in which a large diameter ring part and a small diameter ring part separated in an axial direction are connected by a plurality of pillar parts that are in sliding contact with outer circumferential surfaces of the tapered rollers, and having a plurality of pockets that house and retain the tapered rollers,
• the inner ring including a large diameter-side end and a small diameter-side end, and only the large diameter-side end being formed with a flange part, wherein:
• the neighboring pillar parts constitute a first engagement allowance in which an inner diameter-side opening width of each of the pockets becomes smaller than a roller diameter at a position of the opening width in a direction of a rotation axis of each of the tapered rollers at at least a part of an inner diameter side of each of the pockets;
• the neighboring pillar parts constitute a second engagement allowance in which an outer diameter-side opening width of each of the pockets becomes smaller than the roller diameter at a position of the opening width in the direction of the rotation axis of each of the tapered rollers at at least a part of an outer diameter side of each of the pockets;
• recesses are formed in small diameter-side end faces of the tapered rollers;
• and
• bumps protruding to enter the recesses are formed in an inner surface of the small diameter ring part in the pockets.