Abstract: In a brushless motor comprising: a stator S having a stator core 14 arranged surrounding a bearing part, and a core cover 15 arranged on a surface of the stator core; and a rotor R having a rotational shaft 22, a rotor case 21, and a drive magnet 25, the core cover 15 itself has an integrally formed rotor retaining part that enters a groove 22a in the rotational shaft 22.

Abstract: A cylindrical member is fixed to an upper portion of a rotary shaft and a clamper presses an optical disc in contact with the top of a turntable. The structure is such that a first bottom face of the cylindrical member that faces a clamping magnet in the axial direction is positioned below an opposite face of the clamper that faces the clamping magnet in the axial direction.

Abstract: A cylindrical member is fixed to an upper portion of a rotary shaft and a clamper presses an optical disc in contact with the top of a turntable. The structure is such that a first bottom face of the cylindrical member that faces a clamping magnet in the axial direction is positioned below an opposite face of the clamper that faces the clamping magnet in the axial direction.

Abstract: In addition to a bearing holder being provided with an annular groove that opens down in the axial direction, an end cap is provided with an annular projection that extends up in the axial direction, and by way of press-fitting the projection into the groove, the fitted portion of the bearing holder and the end cap is forms an axially convex labyrinthine shape extending along the entire perimeter.

Abstract: A spindle motor comprises a turntable, on which a disc is loaded, and a motor which rotates the turntable, wherein a top face plate of a magnetic body rotor case, which rotates united with a rotational shaft of the motor, serves as the turntable. A centering member that guides the inner edge of the disc so as to be concentric with the rotational shaft is disposed on the top face plate of the rotor case and a clamping magnet is disposed in a through-opening on the interior of the centering member and is in contact with the top face plate of the rotor case.

Abstract: In a brushless motor comprising: a stator S having a stator core 14 arranged surrounding a bearing part, and a core cover 15 arranged on a surface of the stator core; and a rotor R having a rotational shaft 22, a rotor case 21, and a drive magnet 25, the core cover 15 itself has an integrally formed rotor retaining part that enters a groove 22a in the rotational shaft 22.

Abstract: A simple configuration allows a rotor of a spindle motor to be eccentric in the pickup moving direction, and improves axial run-out caused by clearance between a rotating shaft and bearing. An arc shaped magnetic body is disposed on a base of a spindle motor opposite a drive magnet and in the same direction as the opposing face, thereby generating an attractive force on the outer periphery side of the rotor.

Abstract: A simple construction causes a spindle motor rotor to be eccentric in a pickup moving direction and improves axial run-out caused by clearance between a rotating shaft and a bearing. A magnetic cap is attached to an end of a bearing of a spindle motor so as to cover an end face. A ceiling of the magnetic cap is an annular magnetic material in which a lid and opposing face protruding therefrom are continuous, and the opposing face works with an annular magnet attached to the rotor to generate an attraction force that causes the rotor to be eccentric. The opposing face is formed so as to be linearly symmetrical with respect to the axis line, which is the pickup movement line.

Abstract: A simple configuration allows a rotor of a spindle motor to be eccentric in the pickup moving direction, and improves axial run-out caused by clearance between a rotating shaft and bearing. An arch shaped magnetic body is disposed on a base of a spindle motor opposite a drive magnet and in the same direction as the opposing face, thereby generating an attractive force on the outer periphery side of the rotor.

Abstract: Problem: With a simple constitution, to cause a spindle motor rotor to be eccentric in a pickup moving direction and to improve axial run-out caused by clearance between a rotating shaft and bearing. Means for Solving the Problems: A magnetic cap 40 is attached to an end 7e of a bearing 7 of a spindle motor M so as to cover an end face 7f. A ceiling 41 of the magnetic cap 40 is an annular magnetic material in which a lid 40g and opposing face 40a protruding therefrom are continuous, and the opposing face 40a works with an annular magnet 13 attached to the rotor to generate an attraction force F that causes the rotor R to be eccentric. The opposing face 40a is formed so as to be linearly symmetrical with respect to the axis line Y, which is the pickup movement line.