Abstract: A rotation angle sensor includes: (a) a multi-resolver housing with a high precision structure; (b) stator terminals that do not cause deformation or loosening of terminal pins from the substrates to which they are attached; and (3) a signal line connection structure that is not affected by thermal stress. The housing (10) includes divisional housings (10a, 10b), and one resolver is installed in each of the divisional housings (10a, 10b). The divisional housings (10a, 10b) are assembled by aligning respective openings therein in an axial direction. The lead lines of stator windings are connected to printed circuit substrates (51) installed on insulators (20a, 20b) , and pins (54) connect the printed circuit substrates (51) to a connecting signal output line via flexible connectors (61, 64).

Abstract: To supply a pivot assembly for hard disk drive use that can reliably fix a seal member and solve the problem of out gas, thus reducing the expense and time incidental to the pre-load of a ball bearing. Ball bearings have been joined to both ends of a shaft, and on the outer circumference of these ball bearings, the spacer part is joined to a sleeve disposed between both ball bearings, and a seal member that covers the outer end of the ball bearing has been fixed to the outer circumference of the shaft by laser welding. Because the seal member is fixed by laser welding, the seal member can be reliably fixed and the problem of out gas from the seal member can be solved.

Abstract: A rotation angle sensor includes: (a) a multi-resolver housing with a high precision structure; (b) stator terminals that do not cause deformation or loosening of terminal pins from the substrates to which they are attached; and (3) a signal line connection structure that is not affected by thermal stress. The housing (10) includes divisional housings (10a, 10b), and one resolver is installed in each of the divisional housings (10a, 10b). The divisional housings (10a, 10b) are assembled by aligning respective openings therein in an axial direction. The lead lines of stator windings are connected to printed circuit substrates (51) installed on insulators (20a, 20b), and pins (54) connect the printed circuit substrates (51) to a connecting signal output line via flexible connectors (61, 64).

Abstract: A variable reluctance resolver has a rotor with magnetic poles with 2× or greater axis combination angles, and is structured so that reliable and accurate zero point detection can be carried out. Concave and convex portions are provided on at least two, but fewer than all, of the magnetic poles of the rotor, and the zero point detection winding is provided on a plurality of electrical poles of the stator. Two or more zero point detection signals are generated simultaneously by a plurality of zero point detection windings. Therefore, even if a portion of the zero point detection signals is lost, the zero point can still be identified based on the correlation between the two or more zero point detection signals.

Abstract: A pivot assembly for use in a hard disk drive, in which ball bearings are placed at both ends of a shaft, and a spacer is disposed between outer rings of the ball bearings. The spacer is fixed to the outer rings by laser welding.

Abstract: The bearing device contains two rolling bearings installed on a shaft 9 and a preload is applied to the inner ring of the rolling bearings. The respective dimension for the two rolling bearing inner rings is shortened on both sides in the orientation of the width dimensions of the inner ring, centered on the grooves for the inner ring, with each being set smaller than the dimension of the outer rings. The difference in dimensions is double the difference in the dimensions capable of eliminating rattling of the rolling bearings, when a preload is applied to the outer edge of the inner ring. The outer rings and races are respectively formed to be in a position at half the width dimension of the inner ring from the outer edges of the two outer rings for the two rolling bearings.

Abstract: A pivot bearing includes a stepped shaft having an enlarged diameter shaft portion and a reduced diameter shaft portion; a plurality of balls of a lower row are interposed between the enlarged diameter shaft portion and a sleeve outer ring surrounding the enlarged diameter shaft portion; a ball bearing including inner and outer rings and a plurality of balls interposed therebetween is provided around the reduced diameter shaft portion so that the inner ring is secured around the reduced diameter shaft portion while applying an appropriate pre-load on the upper end surface of the inner ring, and the outer ring is urged to contact the lower surface thereof intimately onto the upper surface of the sleeve outer ring. The pivot bearing has a reduced number of parts, is facilitated in incorporation into a swing arm, and is expected to be manufactured at a reduced cost.

Abstract: A rotation angle sensor and a method of winding a rotation angle sensor involve a single electrical wire that is wound from a rotor transformer to a magnetic rotor. The magnetic rotor is axially spaced on a shaft from the rotor transformer. A notch is formed in a wall of a bobbin of the rotor transformer to permit the wire to pass from the rotor transformer to the magnetic rotor. The ends of the single wire are electrically connected together at a junction, and the junction is fixed to the rotor transformer with resin.

Abstract: An apparatus for a pivot assembly that can strongly and reliably fix a sleeve to an outer ring, and in addition, that can also solve the problem of out gas. Ball bearing 2 are mated to both ends of a shaft 1, and to the outer circumference of these ball bearings 2, an inner wall part 31 mates a sleeve disposed between both ball bearings 2, and the sleeve 3 was fixed by laser welding to the outer ring 22 of the bell bearings 2.

Abstract: There is provided a pivot assembly for a magnetic disk storage which is improved in its rotating accuracy and reduced in manufacturing cost. A pivot assembly includes a pair of ball bearings each having an outer ring, and the outer ring is fitted directly into an axial bore of an actuator block. This arrangement requires no sleeve to be interposed between the pair of ball bearings and the actuator block, thus enabling to reduce its manufacturing cost. No need to interpose any sleeve allows to increase the thickness of the outer ring of the ball bearing and thus the rigidity thereof, thereby improving the rotating accuracy of the pivot assembly.

Abstract: A pivot bearing assembly that can be easily assembled without deformation and featuring a lower amount of outgas and thermal compensation of bond strength. Further, with the pivot bearing assembly, a bearing inner ring and a shaft and a bearing outer ring and a housing are slidingly fitted, bonded and secured to each other with an ultraviolet curing type anaerobic adhesive having a high vitrification temperature, respectively.

Abstract: A rotation angle sensor includes: (a) a multi-resolver housing with a high precision structure; (b) stator terminals that do not cause deformation or loosening of terminal pins from the substrates to which they are attached; and (3) a signal line connection structure that is not affected by thermal stress. The housing (10) includes divisional housings (10a, 10b), and one resolver is installed in each of the divisional housings (10a, 10b). The divisional housings (10a, 10b) are assembled by aligning respective openings therein in an axial direction. The lead lines of stator windings are connected to printed circuit substrates (51) installed on insulators (20a, 20b), and pins (54) connect the printed circuit substrates (51) to a connecting signal output line via flexible connectors (61, 64).

Abstract: A variable reluctance resolver has a rotor with magnetic poles with 2× or greater axis combination angles, and is structured so that reliable and accurate zero point detection can be carried out. Concave and convex portions are provided on at least two, but fewer than all, of the magnetic poles of the rotor, and the zero point detection winding is provided on a plurality of electrical poles of the stator. Two or more zero point detection signals are generated simultaneously by a plurality of zero point detection windings. Therefore, even if a portion of the zero point detection signals is lost, the zero point can still be identified based on the correlation between the two or more zero point detection signals.

Abstract: A rotation angle sensor and a method of winding a rotation angle sensor involve a single electrical wire that is wound from a rotor transformer to a magnetic rotor. The magnetic rotor is axially spaced on a shaft from the rotor transformer. A notch is formed in a wall of a bobbin of the rotor transformer to permit the wire to pass from the rotor transformer to the magnetic rotor. The ends of the single wire are electrically connected together at a junction, and the junction is fixed to the rotor transformer with resin.

Abstract: A bearing suitable for use in PC card type ultra-thin hard disk drive devices is provided. The bearing device includes two bearings assembled on a shaft. Each bearing includes an inner ring, an outer ring and rolling members such as balls. The outer rings of the bearings are in close contact with each other. A space greater than 2&dgr;, i.e., the sum of axial one-sided rattle &dgr; of each of the two bearings is created between the two inner rings by virtue of a difference between the total width dimensions of the two outer rings and the total width dimensions of the two inner rings. Therefore, the amount of preload applied to the outer edge of either inner ring can be adjusted over a wide range and the rattling of the bearing device can be eliminated, and at the same time the desired precision and rigidity of the bearing device can be maintained. The ends of the bearings with inner ring and the outer ring aligned are apart from each other when the bearings are assembled.

Abstract: The bearing device contains two rolling bearings installed on a shaft 9 and a preload is applied to the inner ring of the rolling bearings. The respective dimension for the two rolling bearing inner rings is shortened on both sides in the orientation of the width dimensions of the inner ring, centered on the grooves for the inner ring, with each being set smaller than the dimension of the outer rings. The difference in dimensions is double the difference in the dimensions capable of eliminating rattling of the rolling bearings, when a preload is applied to the outer edge of the inner ring. The outer rings and races are respectively formed to be in a position at half the width dimension of the inner ring from the outer edges of the two outer rings for the two rolling bearings.

Abstract: An apparatus for a pivot assembly that can strongly and reliably fix a sleeve to an outer ring, and in addition, that can also solve the problem of out gas. Ball bearings 2 are mated to both ends of a shaft 1, and to the outer circumference of these ball bearings 2, an inner wall part 31 mates a sleeve disposed between both ball bearings 2, and the sleeve 3 was fixed by laser welding to the outer ring 22 of the ball bearings 2.

Abstract: To supply a pivot assembly for hard disk drive use that can reliably fix a seal member and solve the problem of out gas, thus reducing the expense and time incidental to the pre-load of a ball bearing. Ball bearings have been joined to both ends of a shaft, and on the outer circumference of these ball bearings, the spacer part is joined to a sleeve disposed between both ball bearings, and a seal member that covers the outer end of the ball bearing has been fixed to the outer circumference of the shaft by laser welding. Because the seal member is fixed by laser welding, the seal member can be reliably fixed and the problem of out gas from the seal member can be solved.

Abstract: A pivot assembly for use in a hard disk drive, in which ball bearings are placed at both ends of a shaft, and a spacer is disposed between outer rings of the ball bearings. The spacer is fixed to the outer rings by laser welding.

Abstract: In order to facilitate fixing a pivot assembly to an actuator block and to obtain the stable coaxiality, a screw hole passing from the outside is provided towards a fitting hole into which the pivot assembly is inserted. Moreover, a set screw is screwed into a screw hole to press a sleeve of the pivot assembly, which has been inserted into the fitting hole with an end portion of the set screw. The sleeve pressed at a pressure F1 with the set screw is clamped and fixed by a inside wall surface of the fitting hole and the end portion of the set screw revealing in the inner side of the fitting hole.