A protrusion includes a leading end to which a yoke is fixed and a connector that connects an axially lower end of a flange and the leading end. A minimum width of the connector in a direction intersecting a direction in which the protrusion protrudes is smaller than a maximum width of the leading end in a radial direction. A radial position at a radially inner end of the leading end is located radially outward with respect to a side surface in a radially inward direction of a magnet.

In this stator, a passage line extending in a circumferential direction is disposed in a circumferential gap between two circumferentially adjacent ones of coils. A lead wire continuous with a conducting wire defining one of the coils includes a bend portion being bent in the gap with the passage line serving as a supporting point; a led-out portion arranged to extend from the coil to one side in an axial direction to the bend portion; and a connection portion arranged to extend from the bend portion to another side in the axial direction. At least a portion of a portion of the lead wire which overlaps with the passage line when viewed in a radial direction is arranged at a radial position between the passage line and a core back. Thus, the lead wire is bent with the passage line serving as the supporting point to reverse the direction in which the lead wire runs in the axial direction, and this contributes to preventing a slackening of the connection portion of the lead wire from causing the lead wire to be slackened to the one side in the axial direction. This in turn reduces the likelihood that the lead wire will be brought into contact with a member arranged on the one side of the stator in the axial direction.

A hub of this motor includes a hub annular portion being annular and arranged above a stator, and a flange portion arranged to extend radially outward from the hub annular portion, and including an upper surface on which an annular member is arranged. A yoke includes a first yoke cylindrical portion to which a magnet is fixed; a yoke annular portion arranged to extend radially inward from an upper end of the first yoke cylindrical portion, and including an upper surface arranged opposite to a lower surface of the hub; and a second yoke cylindrical portion arranged to extend axially upward from a radially inner end portion of the yoke annular portion. An inner circumferential surface of the hub annular portion and an outer circumferential surface of the second yoke cylindrical portion are fixed to each other at an engagement portion arranged radially inward of a radially inner end portion of each of coils.

This motor includes a base and a circuit board arranged on a lower surface of the base. The base includes a first annular portion and a second annular portion. The first annular portion is arranged under a stator. The second annular portion is arranged under a flange portion of a hub. A conducting wire drawn out from the stator is arranged to pass through a through hole defined in the first annular portion, and is soldered to a land portion of the circuit board. The second annular portion is arranged to have an axial thickness smaller than that of the first annular portion. The land portion is arranged radially inward of the through hole. The above arrangement makes it easier to achieve a reduced axial dimension of the motor while ensuring a sufficient axial dimension of the hub, which is arranged axially above the second annular portion.

A magnetic disk device includes a plurality of disk-shaped magnetic disks 30, spacers 80, a hub 90, a clamp 70, and a fastening member 72. Each of the magnetic disks 30 includes a through-hole in a center section thereof. Each of the spacers 80 includes a through-hole in a center section thereof, and is disposed among the magnetic disks 30. The hub 90 is inserted into the through-holes of the magnetic disks 30 and the spacers 80. The clamp 70 presses and holds the magnetic disks 30 and the spacers 80. The fastening member 72 fastens the clamp 70 to the hub 90. The clamp 70 is fastened to the hub by the fastening member 72 with a torque of from 5 cN.Math.m to 45 cN.Math.m.

In this stator, a passage line extending in a circumferential direction is disposed in a circumferential gap between two circumferentially adjacent ones of coils. A lead wire continuous with a conducting wire defining one of the coils includes a bend portion being bent in the gap with the passage line serving as a supporting point; a led-out portion arranged to extend from the coil to one side in an axial direction to the bend portion; and a connection portion arranged to extend from the bend portion to another side in the axial direction. At least a portion of a portion of the lead wire which overlaps with the passage line when viewed in a radial direction is arranged at a radial position between the passage line and a core back. Thus, the lead wire is bent with the passage line serving as the supporting point to reverse the direction in which the lead wire runs in the axial direction, and this contributes to preventing a slackening of the connection portion of the lead wire from causing the lead wire to be slackened to the one side in the axial direction. This in turn reduces the likelihood that the lead wire will be brought into contact with a member arranged on the one side of the stator in the axial direction.

This motor includes a base and a circuit board arranged on a lower surface of the base. The base includes a first annular portion and a second annular portion. The first annular portion is arranged under a stator. The second annular portion is arranged under a flange portion of a hub. A conducting wire drawn out from the stator is arranged to pass through a through hole defined in the first annular portion, and is soldered to a land portion of the circuit board. The second annular portion is arranged to have an axial thickness smaller than that of the first annular portion. The land portion is arranged radially inward of the through hole. The above arrangement makes it easier to achieve a reduced axial dimension of the motor while ensuring a sufficient axial dimension of the hub, which is arranged axially above the second annular portion.

A motor that rotates an annular member includes a stationary portion including a stator, and a rotating portion arranged to be rotatable about a central axis extending in a vertical direction. The rotating portion includes a hub extending in an annular shape around the central axis; a magnet including a pole surface arranged radially opposite to the stator; and a yoke to which the magnet is fixed. The yoke includes a yoke increased thickness portion arranged radially outside of the magnet; and a yoke decreased thickness portion with a radial thickness smaller than that of the yoke increased thickness portion, and arranged axially above the yoke increased thickness portion. The yoke decreased thickness portion is fixed to the hub annular portion through press fitting.

To provide an outer rotor type motor capable of suppressing the runout of a top surface by improving the strength in a fitted part between a rotor yoke and a rotor shaft and suppressing resonance between vibration generated by rotation of a rotated body to be a load and motor vibration to thereby realize noise reduction. A rotor yoke is configured so that a rotor hub is fitted to a top surface portion formed in a cup shape integrally with a rotor shaft, and a reinforcing hub concentrically fixed to the rotor shaft with the rotor yoke is arranged so as to overlap the rotor hub.

This motor is arranged to rotate an annular member, and includes a stationary portion including a stator, and a rotating portion arranged to be rotatable about a central axis extending in a vertical direction. The rotating portion includes a hub arranged to extend in an annular shape around the central axis; a magnet including a pole surface arranged radially opposite to the stator; and a yoke to which the magnet is fixed. The hub includes a hub annular portion in the shape of a circular ring and arranged above the stator, and a flange surface on which the annular member is arranged. The yoke includes a yoke increased thickness portion arranged radially outside of the magnet; and a yoke decreased thickness portion arranged to have a radial thickness smaller than that of the yoke increased thickness portion, and arranged axially above the yoke increased thickness portion. The yoke decreased thickness portion is fixed to the hub annular portion through press fitting.