Press system with embossing foil free to expand for nano-imprinting of recording media
View Patent ↗A press system including a first die and a second die. The press system further includes a mandrel extending along a longitudinal mandrel axis through the first die. A rod portion of the mandrel to receive a magnetic recording disk to be pressed. The press system further includes a foil holder coupled to the first die. The foil holder to clamp a first portion of an embossing foil to the first die and allow the clamped foil portion to move in a radial direction relative to the foil holder.
1. A press system, comprising:
a first die;
a second die;
a mandrel extending along a longitudinal mandrel axis through the first die, a rod portion of the mandrel to receive a magnetic recording disk to be pressed; and
a first foil holder coupled to the first die, the first foil holder to clamp a first portion of an embossing foil between the first foil holder and the first die and allow the clamped first portion of the embossing foil to move in a radial direction relative to the first foil holder.
2. The press system as in claim 1 , wherein the embossing foil has an annular shape, the first portion comprising at least a portion of an outer perimeter of the embossing foil.
3. The press system as in claim 2 , wherein the first foil holder comprises a tab contacting a surface of the embossing foil to clamp at least a portion of the outer perimeter of the embossing foil between the tab and a first surface of the first die.
4. The press system as in claim 3 , wherein the first surface of the first die comprises an elastomer.
5. The press system as in claim 2 , wherein an outer diameter of the embossing foil is at least 0.1 mm smaller than a diameter of a recess in the first die into which the embossing foil is clamped.
6. The press system as in claim 1 , wherein the first foil holder is affixed to the first die to provide a predetermined foil clamping force, substantially parallel to the longitudinal mandrel axis, against a first surface of the first die.
7. The press system as in claim 6 , wherein the predetermined foil clamping force is between approximately 5 and 30 N.
8. The press system as in claim 6 , wherein the first foil holder is affixed to the first die with a coil spring compressed between a rigid body comprising the first foil holder and a tensioning screw mounted to the first die.
9. The press system as in claim 8 , wherein the coil spring is one of a plurality of coil springs spaced apart by an angular distance, wherein each coil spring is compressed between a rigid body comprising the first foil holder and a tensioning screw mounted to the first die to provide the predetermined foil clamping force.
10. The press system as in claim 9 , wherein the plurality of springs consists of 6 springs providing a total foil clamping force of between approximately 10 N and 20 N.
11. The press system as in claim 3 , wherein at least a portion of an inner perimeter of the embossing foil is rigidly affixed to a mandrel sleeve surrounding the rod portion of the mandrel to prohibit radial movement of the embossing foil relative to the mandrel sleeve.
12. The press system as in claim 1 , further comprising a second foil holder, wherein the second foil holder comprises a tab contacting a surface of a second embossing foil to clamp a portion of an outer perimeter of the second embossing foil between the tab and a surface of the second die.
13. The press system as in claim 12 , wherein an outer diameter of the second embossing foil is at least 0.1 mm smaller than a diameter of a recess in the second die to provide a gap for radial movement of the clamped second foil portion of the outer perimeter of the second embossing foil.