Abstract: A tolerance ring that has a ring shape approximately circling along a predetermined direction includes a plurality of projections, wherein the curvature radiuses of end portions in a circling direction are smaller than the curvature radius of a portion other than the end portions in the circling direction.

Abstract: A tolerance ring that has a ring shape approximately circling along a predetermined direction includes a plurality of projections, wherein the curvature radiuses of end portions in a circling direction are smaller than the curvature radius of a portion other than the end portions in the circling direction.

Abstract: A clamp for a disk rotation driver stably and surely supports a disk in the disk rotation driver. The clamp 7 for a disk rotation driver 1 having a central portion and a periphery being circumferentially provided with a contact portion 13, the central portion fastened to a hub 5 to be rotated, and the contact portion 13 pressed against a recordable disk 3 attached to the hub 5 to apply a pressing force Fv to the disk 3 in a rotation axis direction and fixedly support the magnetic disk 3 on the hub 5, the clamp 7 comprising: a wall portion 25 extending from the periphery and being oriented in the rotation axis direction to form the contact portion 13 so that a frictional force ?Fy produced between the contact portion 13 and the magnetic disk 3 and resisting a locomotion Fx that acts on the contact portion 13 and radially outwardly biases the contact portion 13 when the contact portion 13 is in contact with the magnetic disk 3 is equal to or larger than the locomotion Fx.

Abstract: A disc can be supported stably and surely.