Bearing having cylindrical member connected to outer member of bearing

A bearing comprising:

• an outer member rotatably coupled to an inner ring of the bearing via rolling members;
• a cylindrical member connected to the outer member;
• and
• a plurality of grooves formed on the outer member for firmly connecting the cylindrical member to the outer member, wherein:
• the plurality of grooves have inclinations relative to an axial direction of the bearing and are formed so that the grooves do not cross one another;
• the plurality of grooves are grouped into several groups, and the grooves in each group have the same inclination relative to the axial direction of the bearing,
• when viewed along a direction perpendicular to the axial direction of the bearing, each of the plurality of grooves is provided by a straight line inclined relative to the axial direction of the bearing,
• the several groups are formed on an outer peripheral surface of the outer member and segmented by predetermined circumferential angles, respectively, and
• the several groups are separated from each other by predetermined clearances.