To provide a crown type cage for a ball bearing, without increasing a torque loss when the bearing rotates, by stably supplying grease to a pocket inner surface from a grease passage.
A circular arc part 2a forming a pocket 3 and a grease storage part 4 hollowed in along a connecting part 2b connecting the adjacent circular arc part 2a, are arranged in a thickness central part in the radial direction on the opposite side of an opening 3a of the pocket 3 of an annular body 2. The outflow of the grease from the grease storage part 4 by gravity and centrifugal force, is prevented by installing an annular cover member 5 for enclosing these grease storage parts 4 except for a part of the grease passage 6, and the grease can be stably supplied to the inner surface of the pocket 3 from the grease passage 6, and the torque loss is not increased when the bearing rotates.
Torii Kazuhisa
Takayoshi Tagawa
Higashio Masahiro