Disk clamp for disk recording apparatus and disk recording apparatus

A disk recording apparatus, comprising:

• a hub adapted to be secured to a spindle shaft and having an axis of rotation and an outer diameter wall;
• recording disks concentrically disposed on the hub and having circumferential recording tracks on glass substrates and inner diameter edges;
• a clamp mounted to the hub axially outboard of the recording disks far retaining the recording disks on the hub;
• a thermal strain buffer located between the clamp and the recording disks, the thermal strain buffer being completely axially outboard of the recording disks and in a parallel orientation with respect to the recording disks;
• the thermal strain buffer being formed from a single, homogenous, flat sheet of material, having an axial thickness in a range of 0.1 to 0.2 mm, that is stable in terms of chemical properties aver an operating temperature range of the disk recording apparatus, and has a thermal expansion coefficient similar to that of the glass substrates;
• and
• other ones of the recording disks are spaced apart by an axial distance that is much greater than the axial thickness of the thermal strain buffer.

A disk recording apparatus, comprising:

• a hub adapted to be secured to a spindle shall and having an axis of rotation and an outer diameter wall;
• recording disks concentrically disposed on the hub and having circumferential recording tracks on glass substrates and inner diameter edges, the outer diameter wall of the hub and the inner diameter edges of the recording disks being unobstructed;
• a clamp mounted to the hub axially outboard of the recording discs for retaining the recording disks on the hub;
• a thermal strain buffer located between the clamp and an adjacent recording disk, the thermal strain buffer being completely axially outboard of the recording disks and in a parallel orientation with respect to the recording disks;
• ceramic spacers between adjacent ones of the recording disks, such that the ceramic spacers are the only structures located directly between adjacent ones of the recording disks;
• the thermal strain buffer being fromed from a single, homogenous, flat sheet of titanium material having a thickness in a range of 0.1 to 0.2 mm, that is stable in terms of chemical properties over an operating temperature range of the disk recording apparatus, and has a thermal expansion coefficient similar to that of the glass substrates;
• and
• the ceramic spacers axially space apart said adjacent ones of the recording disks by a first distance, the thermal strain buffer axially spaces apart the clamp from the adjacent recording disk by a second distance, and the first distance is significantly greater than the second distance.