Chucking device with a cone including a sliding portion, brushless motor using the same, and disk drive apparatus using the same

A chucking device for removably holding a disk with a central opening, comprising:

• a shaft coaxially arranged with a specified central axis;
• a turntable fixed to the shaft, the turntable including a disk support surface arranged to support the disk;
• a cone arranged axially above the turntable, the cone including a sliding portion arranged to make vertical sliding movement with respect to the shaft and a disk holding portion having an annular disk holding surface inclined radially outwards and axially downwards;
• an annular yoke arranged above the sliding portion of the cone and fixed to the shaft;
• and
• a clamp magnet fixed to the yoke through an adhesive agent;
• wherein the yoke includes an upper surface having an annular recess defined in a concentric relationship with the central axis, at least a part of the adhesive agent being applied on a region of the upper surface existing radially inwards of the recess;
• the recess includes a radial outer wall parallel to the central axis or inclined radially outwards and axially upwards, and a radial inner wall inclined radially inwards and axially upwards;
• and
• the angle between the radial outer wall and a lower surface of the clamp magnet is greater than the angle between the radial inner wall and the lower surface of the clamp magnet.

A brushless motor comprising:

• a chucking device, a rotor unit, and a stator unit,
• wherein the chucking device for removably holding a disk with a central opening comprises;
• a shaft coaxially arranged with a specified central axis;
• a turntable fixed to the shaft, the turntable including a disk support surface arranged to support the disk;
• a cone arranged axially above the turntable, the cone including a sliding portion arranged to make axial sliding movement with respect to the shaft and a disk holding portion having an annular disk holding surface inclined radially outwards and axially downwards;
• an annular yoke arranged above the sliding portion of the cone and fixed to the shaft;
• and
• a clamp magnet fixed to the yoke through an adhesive agent;
• wherein the yoke includes an upper surface having an annular recess defined in a concentric relationship with the central axis, at least a part of the adhesive agent being applied on a region of the upper surface existing radially inwards of the recess;
• the recess includes a radial outer wall parallel to the central axis or inclined radially outwards and axially upwards, and a radial inner wall inclined radially inwards and axially upwards;
• and the angle between the radial outer wall and the central axis is smaller than the angle between the radial inner wall and the central axis,
• wherein the rotor unit includes a rotor magnet arranged to rotate about the central axis together with the shaft, the chucking device being attached to the rotor unit;
• and
• wherein the stator unit includes a stator arranged to generate magnetic fields toward the rotor magnet.

A disk drive apparatus, comprising:

• a brushless motor arranged to rotate a disk;
• an optical pickup mechanism, and
• a moving mechanism;
• wherein the brushless motor comprising:
• a chucking device, a rotor unit, and a stator unit,
• wherein the chucking device for removably holding a disk with a central opening comprises:
• a shaft coaxially arranged with a specified central axis;
• a turntable fixed to the shaft, the turntable including a disk support surface arranged to support the disk;
• a cone arranged axially above the turntable, the cone including a sliding portion arranged to make axial sliding movement with respect to the shaft and a disk holding portion having an annular disk holding surface inclined radially outwards and axially downwards;
• an annular yoke arranged above the sliding portion of the cone and fixed to the shaft;
• and
• a clamp magnet fixed to the yoke through an adhesive agent;
• wherein the yoke includes an upper surface having an annular recess defined in a concentric relationship with the central axis, at least a part of the adhesive agent being applied on a region of the upper surface existing radially inwards of the recess;
• the recess includes a radial outer wall parallel to the central axis or inclined radially outwards and axially upwards, and a radial inner wall inclined radially inwards and axially upwards;
• and the angle between the radial outer wall and the central axis is smaller than the angle between the radial inner wall and the central axis,
• wherein the a rotor unit includes a rotor magnet arranged to rotate about the central axis together with the shaft, the chucking device being attached to the rotor unit;
• and
• wherein the stator unit includes a stator arranged to generate magnetic fields toward the rotor magnet,
• wherein the optical pickup mechanism includes a recording and reproducing unit arranged to perform at least one of optical recording and reproducing tasks with respect to the disk;
• and
• wherein the moving mechanism is arranged to move the optical pickup mechanism in a radial direction of the disk.

A brushless motor comprising:

• a chucking device, a rotor unit, and a stator unit,
• wherein the chucking device for removably holding a disk with a central opening comprises:
• a shaft coaxially arranged with a specified central axis;
• a turntable fixed to the shaft, the turntable including a disk support surface arranged to support the disk;
• a cone arranged axially above the turntable, the cone including a sliding portion arranged to make vertical sliding movement with respect to the shaft and a disk holding portion having an annular disk holding surface inclined radially outwards and axially downwards;
• an annular yoke arranged above the sliding portion of the cone and fixed to the shaft;
• and
• a clamp magnet fixed to the yoke through an adhesive agent;
• wherein the yoke includes an upper surface having an annular recess defined in a concentric relationship with the central axis, at least a part of the adhesive agent being applied on a region of the upper surface existing radially inwards of the recess;
• the recess includes a radial outer wall parallel to the central axis or inclined radially outwards and axially upwards, and a radial inner wall inclined radially inwards and axially upwards;
• and the angle between the radial outer wall and a lower surface of the clamp magnet is greater than the angle between the radial inner wall and the lower surface of the clamp magnet,
• wherein the rotor unit includes a rotor magnet arranged to rotate about the central axis together with the shaft, the chucking device being attached to the rotor unit;
• and
• wherein the stator unit includes a stator arranged to generate magnetic fields toward the rotor magnet.

A disk drive apparatus, comprising:

• a brushless motor arranged to rotate a disk;
• an optical pickup mechanism, and a moving mechanism;
• wherein the brushless motor comprising:
• the chucking device, a rotor unit, and a stator unit,
• wherein the chucking device for removably holding a disk with a central opening comprises:
• a shaft coaxially arranged with a specified central axis;
• a turntable fixed to the shaft, the turntable including a disk support surface arranged to support the disk;
• a cone arranged axially above the turntable, the cone including a sliding portion arranged to make vertical sliding movement with respect to the shaft and a disk holding portion having an annular disk holding surface inclined radially outwards and axially downwards;
• an annular yoke arranged above the sliding portion of the cone and fixed to the shaft;
• and
• a clamp magnet fixed to the yoke through an adhesive agent;
• wherein the yoke includes an upper surface having an annular recess defined in a concentric relationship with the central axis, at least a part of the adhesive agent being applied on a region of the upper surface existing radially inwards of the recess;
• the recess includes a radial outer wall parallel to the central axis or inclined radially outwards and axially upwards, and a radial inner wall inclined radially inwards and axially upwards;
• and the angle between the radial outer wall and a lower surface of the clamp magnet is greater than the angle between the radial inner wall and the lower surface of the clamp magnet,
• wherein the rotor unit includes a rotor magnet arranged to rotate about the central axis together with the shaft, the chucking device being attached to the rotor unit;
• and
• wherein the stator unit includes a stator arranged to generate magnetic fields toward the rotor magnet,
• wherein the optical pickup mechanism includes a recording and reproducing unit arranged to perform at least one of optical recording and reproducing tasks with respect to the disk;
• and
• wherein the moving mechanism is arranged to move the optical pickup mechanism in a radial direction of the disk.