Prong type resin cage for double row roller bearing and double row roller bearing

A double row roller bearing comprising:

• an inner ring;
• an outer ring;
• a plurality of rollers arranged in two rows between the inner ring and the outer ring;
• and
• a plurality of independent cages each of which holds the rollers arranged in a corresponding one of the rows, wherein
• each of the cages is a prong type resin cage having an annular portion and a plurality of cage bars extended in an axial direction of the prong type resin cage from one side face of the annular portion, and located at intervals in a circumferential direction of the prong type resin cage,
• each of the cage bars has a roller guide face formed in each opposed face of the cage bar, the opposed face being opposed to an outer peripheral face of a corresponding one of the rollers, the roller guide face being used for roller guide by the outer peripheral face when the prong type resin cage is rotated at a rotational speed equal to or lower than a prescribed rotational speed, and
• a cage outer face including an outer peripheral face of the annular portion and radially outer faces of the cage bars has outer ring guide faces of which diameter is increased radially outward by a centrifugal force to decrease a radial clearance between the outer ring guide faces and an inner peripheral face of the outer ring, so that outer ring guide by the inner peripheral face of the outer ring is carried out, when the rotational speed of the prong type resin cage exceeds the prescribed rotational speed,
• wherein the radially outer face of each of the came bars is an inclined face formed such that a radial clearance between the radially outer face and the inner peripheral face of the outer ring increases along a direction toward a distal end of the cage bar.

A prong type resin cage that is incorporated in a double row roller bearing in which multiple rollers are arranged in two rows between an inner ring and an outer ring, and that holds the rollers arranged in one of the two rows, the prong type resin cage comprising:

• an annular portion;
• and
• a plurality of cage bars extended in an axial direction of the prong type resin cage from one side face of the annular portion, and located at intervals in a circumferential direction of the prong type resin cage, wherein
• each of the cage bars has a roller guide face formed in each opposed face of the cage bar, the opposed face being opposed to an outer peripheral face of a corresponding one of the rollers,
• a cage outer face including an outer peripheral face of the annular portion and radially outer faces of the cage bars has outer ring guide faces, wherein the radially outer face of each of the cage bars is an inclined face formed such that a radial clearance between the radially outer face and the inner peripheral face of the outer ring increases along a direction toward a distal end of the cage bar.