Abstract: A hard disc drive is disclosed, which comprises a compound bearing assembly including a stepped shaft 1 having a large-diameter portion 1a and a small-diameter portion 1b, the large-diameter portion 1a having an inner raceway groove 2a formed in the outer periphery, an outer race ring 3 surrounding the large-diameter portion 1a and having an outer raceway groove 2b, a plurality of balls 4 provided between the inner and outer raceway grooves 2a and 2b, a ball bearing unit 5 having an inner and an outer race ring 5a and 5b and a plurality of balls 6 provided therebetween, the inner race ring 5a being fitted on the small-diameter portion 1b, and a sleeve-like spacer 7 surrounding the stepped shaft 1and having opposite end small-diameter portions, the outer race ring 3 and the outer race ring 5b of the ball bearing unit 5 being fitted on the opposite end small-diameter portions, respectively.

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 hard disc drive is disclosed, which comprises a compound bearing assembly including stepped shaft 1 having a large-diameter portion 1a and a small-diameter portion 1b, a plurality of balls 4 provided between an outer raceway groove 2b formed in the inner periphery of an outer race ring 3 and an inner raceway groove 2a directly formed in the outer periphery of the large-diameter portion 1a, and a plurality of balls 8a provided between an inner raceway groove 6a formed in the outer periphery of an inner race ring 7a fitted on the small-diameter portion 1b of the stepped shaft 1 and an outer raceway groove 6b directly formed in the inner periphery of a portion of a sleeve-like outer race ring 5 adjacent an end thereof. A hub 12 of a rotor 11 of a motor of the hard disc drive is fitted on the compound bearing assembly.

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 first outer race ring 3, a sleeve-like spacer 7, a plurality of first balls 4, a conventional ball bearing unit 5 and a stepped-diameter shaft 1 are assembled into a compound bearing assembly by a bearing maker to enable a user or motor manufacturer to be free from a cumbersome assembling work of the bearing assembly. Consequently, upon receipt of the bearing assembly, the motor manufacturer may immediately mount the bearing assembly in a central hub portion of a rotor of the motor in an insertion manner to complete his product, i.e., high-performance motor.

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 single-piece outer race ring 3, a sleeve-like spacer 11, a plurality of first balls 4, a conventional ball bearing unit 7, a stepped-diameter shaft 1 and the like are assembled into a compound bearing assembly by a bearing maker with high accuracy to enable a user to be free from a cumbersome assembling work of rotating portions or cylindrical rotary shaft and its bearing means of a computer and its peripheral devices. In use, the compound bearing assembly is coaxially mounted in the cylindrical rotary shaft and the like at the user's end to rotatably support the cylindrical rotary shaft and the like in the computer and its peripheral devices.

Abstract: The drive unit is improved in precision while the number of its manufacturing steps is a minimum. The drive unit reduces its manufacturing cost, and comprises a base plate 1 assuming a predetermined shape in cross-section so as to form a pair of frame portions 2 in its opposite sides. The plate 1 is made of metal, formed by using an extrusion process, and provided with: a concave portion 4 with a central hole 3a through which a motor M is mounted on the plate 1; and, a mounting hole 3c through which a swing arm is mounted on the plate 1. The motor M has its spindle 5 mounted in the central hole 3a of the plate 1 in an insertion manner. The swing arm 6 has its base portion supported by a pivot 8 through a pair of ball bearings 7. The pivot 8 is mounted on the plate 1 through the mounting hole 3c in an insertion manner.

Abstract: In the stepping motor, in which the stator core 4 is disposed outside the rotor 2 mounted on the rotation shaft, by the bearings 8, 9 mounted on the casings 10, the front and rear portion of the rotation shaft 1 are supported, and the casings 10, 11 are made of a press-molded metal plate.The thin portions 10b, 11b of the casings 10, 11, which are in contact with the stator core 4 support one portion of the outer circumference of the stator core 4. Also, by the alternately folded portions 10c, 11c of the thin portions and the projections 10d, 11d the bearings 8, 9 are supported. Whereby, the thin portions 10b, 11b cover one portion of the stator core, so that dusts are prevented from being entered. Further, the folded portions 10c, 11c and the projections 10d, 11d enable the bearings 8, 9 to install and keep the correct posture.

Abstract: An integral bearing type electric motor is disclosed, which comprises a bearing body including a spindle, a sleeve surrounding the spindle, an inner or outer ring fitted in or on the spindle, and balls provided between the spindle and sleeve, between the spindle and outer ring or between the inner ring and sleeve. A hub for the rotor of the motor, a flange for the base of the motor or a stator yoke holder is formed by molding together with the sleeve, spindle or inner ring of the bearing body. The number of components is reduced, the number of assembling steps can be reduced, and reduction of the cost of manufacture can be expected.

Abstract: A bearing assembly, and method of assembling same, including a stepped-diameter shaft, a first outer race ring being disposed around a raceway groove directly formed in the large diameter portion, a second bearing outer race and an inner race ring mounted on the small diameter portion of the shaft, and a sleeve-like spacer provided with a pair of small diameter portions in its opposite axial end portions each fitted into in the respective first and second outer races.

Abstract: In the manufacture of a casing base for a hard disc drive device, an elongate semi-product of a light metal having a predetermined sectional profile having opposite side frame portions, is extrusion molded and then cut to a predetermined length to obtain an eventual casing base, which is then formed with necessary holes and recessed or raised portions using a press, thus completing the casing base. Like the case of die casting, no cavities are generated, so that it is possible to readily carry out washing and surface treatment. In addition, unlike the case of forming frames in a sole press process, a large number of press forming steps are not involved, and it is possible to permit mass production of a highly accurate and highly rigid product in a small number of steps and at a low cost of manufacture.

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.