Abstract: A compound ball bearing comprises a bearing assembly including a spindle 1, a sleeve 2 surrounding the spindle 1, and an inner ring 6 fitted on the spindle or an outer ring fitted in the sleeve, and balls 5, 9 provided between the spindle 1 and the sleeve 2, between the spindle and outer ring or between the inner ring 6 and sleeve 2. A base 16 of a motor is formed as a one-piece unit with the spindle. The vibration accuracy of the spindle 1 can be improved.

Abstract: A compound ball bearing type pulley comprises a bearing assembly including a spindle 1, a sleeve 2 surrounding the spindle 1 with outer flanges 22a, 22b formed on upper and lower ends of the sleeve and an inner ring fitted on the spindle. Balls 5, 9 are provided and between the spindle 1 and sleeve 2, between the inner ring 6 and sleeve 2. Conventional outer rings are not necessary and the outer diameter of the pulley can be made smaller.

Abstract: A compound ball bearing comprises a bearing body including a spindle 1, a sleeve 2 surrounding the spindle 1, and an inner ring fitted on the spindle or an outer ring fitted in the sleeve, and balls 5, 9 provided between the spindle 1 and sleeve 2, between the spindle and outer ring or between the inner ring 6 and sleeve 2. A motor component such as a hub 11 for the rotor, a flange for the motor base or a yoke yolder is molded as a one-piece molding with the sleeve, spindle or inner ring. The inner or outer ring can be secured in a proper position by facilitating its pre-loading, and the vibration accuracy of the spindle can be improved.

Abstract: A compound ball bearing for swing arm unit acomprises a bearing assembly including a spindle 1, a sleeve 2 surrounding the spindle 1, an inner ring fitted on the spindle, with balls 5 and 9 being provided between the spindle 1 and sleeve 2, between the inner ring 6 and sleeve 2. A swing arm 22 is mounted on the sleeve 2. Conventional outer rings are not necessary and the outer diameter of the sleeve can be made smaller than conventional devices.

Abstract: A compound ball bearing comprises a bearing assembly including a spindle 1, a sleeve 2 surrounding the spindle 1, and an inner ring 6 fitted on the spindle or an outer ring fitted in the sleeve, and balls 5, 9 provided between the spindle 1 and sleeve 2, between the spindle and outer ring or between the inner ring 6 and sleeve 2. A hub 11 serving as the rotor of a motor is formed as a one-piece unit with the spindle. The vibration accuracy of the spindle 1 can be improved.

Abstract: A compound ball bearing comprises a bearing body including a spindle 1, a sleeve 2 surrounding the spindle 1, and an inner ring fitted on the spindle or an outer ring fitted in the sleeve, and balls 5, 9 provided between the spindle 1 and sleeve 2, between the spindle and outer ring or between the inner ring 6 and sleeve 2. A motor component such as a hub 11 for the rotor, a flange for the motor base or a yoke yolder is molded as a one-piece molding with the sleeve, spindle or inner ring. The inner or outer ring can be secured in a proper position by facilitating its pre-loading, and the vibration accuracy of the spindle can be improved.

Abstract: A double-row ball bearing comprises an axle (1) and a sleeve (2). In such ball bearing: a pre-load is axially applied to one of a short straight tube type inner ring (6) which is mounted on the axle (1) and a short straight tube type outer ring (10) which is mounted in a sleeve (2); and the inner ring (6) is fixed to the axle (1) or the outer ring (10) is fixed to the sleeve (2), in a condition in which the pre-load is applied.