Multi-disc servo track writer vibration isolation method and apparatus
View Patent ↗Apparatus and method for orienting a head over a disc within a multi-disc servo-track writer preferably uses two gas bearings, an adaptor plate, and an actuator assembly including an E-block and arm/head assembly. Rotation of the E-block, and hence actuator arm/head assembly, can be controlled by the movement of a rotational gas bearing, which is rotated by a motor. The gas bearing provides for reduced friction and, as a result, decreased eccentricity of the head as compared to related art configurations. A translational gas bearing can be used for laterally positioning the actuator assembly for servo track recording.
1. A track writing apparatus comprising:
an actuator assembly comprising an actuator block having a cavity therein;
a rotational gas bearing housed within the cavity of the actuator block for supporting one or more transducers each for recording information on the track; and
a translational gas bearing formed on the actuator block operable when moving the actuator assembly over a surface of a platform and between a first position and a second position.
2. The track writing apparatus of claim 1 further comprising a stop positioned on the actuator block and a catch supported by the platform, wherein movement of the actuator assembly on the translational gas bearing is positioned in a track writing position when the stop interacts with the catch.
3. The track writing apparatus of claim 1 further comprising a slide mechanism for laterally moving the actuator block on the translational gas bearing between the first and second positions.
4. The trace writing apparatus of claim 1 wherein the translational gas bearing comprises a groove juxtaposed between two landings on the actuator block that extend around a centrally located recess in the actuator block.
5. The track writing apparatus of claim 1 , wherein the rotational gas bearing comprises a rotatable spindle supporting an adaptor plate that in turn supports the transducers.
6. The track writing apparatus of claim 5 further comprising a motor coupled to the rotational gas bearing spindle.
7. The track writing apparatus of claim 6 further comprising a corner cube attached to the adaptor plate, the corner cube providing positional information for controlling the motor to position the transducers.
8. The trace writing apparatus of claim 1 wherein the rotational gas bearing has an axis of rotation substantially parallel to the platform surface.
9. The track writing apparatus of claim 8 wherein the transducers operably rotate around the rotational gas bearing axis of rotation.
10. A method for positioning a servo recording head adjacent a disc in a multi-disc track writer, the method comprising steps of:
(a) applying gas pressure to a translational gas bearing an actuator assembly to provide a float between the actuator assembly and the platform;
(b) laterally moving the actuator assembly on the translational gas bearing to a servo recording position;
(c) removing the gas pressure from the translational gas bearing;
(d) pulling a vacuum on the translational gas bearing to immobilize the actuator assembly against the platform;
(e) applying gas pressure to a rotational gas bearing in the actuator assembly, the rotational gas bearing supporting the servo recording head; and
(f) rotating the servo recording head on the rotational gas bearing.
11. The method of claim 10 wherein applying gas pressure to the translational gas bearing comprises pressurizing a groove juxtaposed between two landings and extending around a centrally located recess in the actuator assembly.
12. The method of claim 10 further comprising steps of:
(h) recording information on the disc;
(i) rotating the servo recording head off of the disc;
(j) removing the gas pressure from the rotational gas bearing;
(k) applying gas pressure and removing the vacuum to the translational gas bearing; and
(l) moving the actuator assembly to a disc loading and unloading position.
13. The method of claim 12 further comprising the steps of:
(m) removing the gas pressure to the translational gas bearing; and
(n) pulling a vacuum on the translational gas bearing to immobilize the actuator assembly in the disc loading and unloading position.
14. A track writing apparatus comprising:
an actuator assembly comprising an actuator block; and
a translational gas bearing formed on the actuator block the translational gas bearing comprising a fluid port adapted for receiving pressurized fluid for spatially separating the actuator block from a support surface, the translational gas bearing further comprising a vacuum port different than the fluid port adapted for receiving a vacuum for fixingly engaging the actuator block against the support surface.
15. The apparatus of claim 14 further comprising a rotational gas bearing supported by the actuator block and supporting, in turn, one or more transducers each for recording information on the track.
16. The apparatus of claim 15 further comprising an adaptor plate connecting the rotational gas bearing and the actuator assembly.
17. The apparatus of claim 15 wherein the rotational gas bearing has an axis of rotation around which the transducers are moveable.
18. The apparatus of claim 15 further comprising a motor coupled to the rotational gas bearing.
19. The apparatus of claim 14 further comprising a slide mechanism for laterally moving the actuator block on the translational gas bearing.
20. The apparatus of claim 14 wherein the translational gas bearing comprises a groove communicating with the fluid port juxtaposed between two landings on the actuator block and extending around a centrally located recess communicating with the vacuum port.