Disk rotating device, disk, disk assembly, disk cartridge, and recording and reproducing device
A disk rotating device includes a flexible disk in which information is recordable, a turntable on which the disk is held, a spindle that rotates the disk held on the turntable, and a stabilizer that stabilizes the rotating disk. In the disk rotating device, a rotation transmitting device transmits the rotation of the spindle to the disk via the turntable, and a disk holding device holds the disk so that the disk is elastically deformable from a center of the rotation of the disk in a radial direction of the disk.
1. A flexible disk in which optical information is recordable, the flexible disk comprising:
an optical information recording portion where the optical information is stored;
a holding part that is held on a turntable of a disk rotating device, the holding part having a front surface and a back surface, and wherein the holding part comprises a hub; and
a first elastic body disposed on the front surface of the holding part, and a second elastic body disposed on the back surface of the holding part, such that the holding part is located between the first elastic body and the second elastic body, and
wherein the first elastic body and the second elastic body are configured to elastically expand in a radial direction of the flexible disk, from an original state, when the optical information recording portion is rotated at high speed during recording and/or reading of the optical information, and wherein the first elastic body and the second elastic body are configured to reversibly return to the original state when rotation of the optical information recording portion is stopped.
2. The flexible disk according to claim 1 , wherein each elastic body is made of a rubber or a cured adhesive, and has a modulus of shearing elasticity of about 10-100 MPa.
3. The flexible disk according to claim 1 , wherein the radius of the hub is substantially equal to the radii of the elastic bodies.
4. The flexible disk according to claim 1 , wherein the flexible disk is configured to be rotated at over 10,000 rpm, and wherein the thickness of each elastic body is about twice as large as the amount of elastic deformation at a peripheral edge of the holding part when the flexible disk is rotated at over 10,000 rpm.