Cage and ball bearing comprising the cage

A cage comprising:

• a first sub-part comprising a plurality of first partitions integrated as a whole and a plurality of first pocket portions formed by adjacent first partitions, wherein a first engaging portion is formed on at least one of the first partitions, one first partition of the plurality of first partitions having a first axial width;
• and
• a second sub-part comprising a plurality of second partitions integrated as a whole and a plurality of second pocket portions formed by adjacent second partitions, wherein a second engaging portion is formed on at least one of the second partitions, and a pocket is formed by the first pocket portion and its corresponding second pocket portion, one second partition of the plurality of second partitions having a second axial width, the first axial width being greater than the second axial width;
• wherein each first engaging portion snaps with its corresponding second engaging portion;
• wherein the plurality of first pocket portions includes a primary first pocket portion and a secondary first pocket portion disposed on opposite sides of said one first partition, wherein the plurality of second pocket portions includes a primary second pocket portion and a secondary second pocket portion disposed on opposite sides of said one second partition, wherein:
• an axial inner side of said one first partition is formed as a first curved surface extending circumferentially from the primary first pocket portion to the secondary first pocket portion, and an axial inner side of said one second partition is formed as a second curved surface matching with the first curved surface, the second curved surface extending circumferentially from the primary second pocket portion to the secondary second pocket portion;
• or
• an axial inner side of said one first partition is formed as a first inclined surface inclined relative to the axial direction, the first inclined surface extending circumferentially from the primary first pocket portion to the secondary first pocket portion, and an axial inner side of said one second partition is formed as a second inclined surface inclined relative to the axial direction and matching with the first inclined surface, the second inclined surface extending circumferentially from the primary second pocket portion to the secondary second pocket portion.