Magnetic disk device having motor

A magnetic disk device comprising:

• a housing;
• a motor including
• a hub being attached to the housing inside the housing so as to be rotatable around a rotation axis relative to the housing, and
• a clamp being attached to the hub;
• a plurality of magnetic disks attached to the motor while aligned with each other along the rotation axis;
• and
• a plurality of spacers attached to the motor, each of which is located between two adjacent magnetic disks among the plurality of magnetic disks or between the clamp and one of the plurality of magnetic disks,
• wherein
• each of the plurality of magnetic disks has a first inner circumferential surface oriented toward the rotation axis,
• each of the plurality of spacers has a second inner circumferential surface oriented toward the rotation axis,
• the hub has
• a support wall supporting a stack of the plurality of magnetic disks and the plurality of spacers, and
• a first outer circumferential surface extending from the support wall in an extension direction along the rotation axis and being in contact with the first inner circumferential surface of at least one of the plurality of magnetic disks and with the second inner circumferential surface of at least one of the plurality of spacers,
• the clamp has
• a second outer circumferential surface being in contact with the second inner circumferential surface of at least one of the plurality of spacers, and
• a retaining wall protruding from the second outer circumferential surface, and
• the clamp holds the stack of the plurality of magnetic disks and the plurality of spacers in-between the support wall and the retaining wall.