Patent US5303105A successfully refreshed from Google Patents.
US5303105A
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Shape memory alloy for centering a transducer carried by a slider in a support arm over a track on a magnetic disk
Assignee: Seagate Technology LLC
•
Filing: 1992-12-16
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Granted: 1994-04-12
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Expires: 2012-12-16
Abstract
Abstract An apparatus positions a transducer, carried by a slider, over a track on a magnetic disk. An arm has a first end for attachment to an actuator for rotating the arm and a second end for attachment to the slider. The arm also has an arm portion extending between the first and second ends. A shape memory alloy is coupled to the arm portion. Thermal energy is selectively applied to the shape memory alloy to cause corresponding deformation of the shape memory alloy causing the arm portion to deflect and move the second end along an arcuate path in a plane substantially transverse to the track.
Inventors
- 👤 David J. Jorgenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/596; G11B5/4806; G11B5/4873; G11B5/54; G11B5/55; G11B5/5521; G11B5/5552
Claims Analysis
Total Claims: 66
Claim 1
Independent Claim
140 words
An apparatus for repositioning a transducer, carried by a slider, over a track on a magnetic disk, comprising: an arm having a first end for attachment to an actuator for rotating the arm, a second end for attachment to the slider, and an arm portion extending between the first and second ends; shape memory alloy means, responsive to thermal energy to deform the shape memory alloy means, being coupled to the arm portion for deforming the arm upon deformation of the shape memory alloy means; and means for selectively applying thermal energy to the shape memory alloy means to cause corresponding deformation of the shape memory alloy means causing the arm to deform and move the second end along an arcuate path in a plane substantially transverse to the track to position the transducer over a center of the track.
Claim 2
Independent Claim
140 words
An apparatus for repositioning a transducer, carried by a slider, over a track on a magnetic disk, comprising: an arm having a first end for attachment to an actuator for rotating the arm, a second end for attachment to the slider, and an arm portion extending between the first and second ends; shape memory alloy means, responsive to thermal energy to deform the shape memory alloy means, being coupled to the arm portion for deforming the arm upon deformation of the shape memory alloy means; and means for selectively applying thermal energy to the shape memory alloy means to cause corresponding deformation of the shape memory alloy means causing the arm to deform and move the second end along an arcuate path in a plane substantially transverse to the track to position the transducer over a center of the track.
Claim 3
Dependent Claim
47 words
The apparatus of claim 1 wherein the arm portion comprises: a data arm portion adapted for being coupled to the actuator; and a first flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a first slider.
Claim 4
Dependent Claim
18 words
The apparatus of claim 2 wherein the shape memory alloy means is coupled to the data arm portion.
Claim 5
Dependent Claim
111 words
The apparatus of claim 3 wherein the shape memory alloy means comprises: a first shape memory alloy element coupled to one side of the data arm portion, deformation of the first shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a first direction; and a second shape memory alloy element coupled to a second side of the data arm portion, the second side being generally opposite the first side, and deformation of the second shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 6
Dependent Claim
17 words
The apparatus of claim 2 wherein the shape memory alloy means is coupled to the first flexure.
Claim 7
Dependent Claim
109 words
The apparatus of claim 5 wherein the shape memory alloy means comprises: a first shape memory alloy element coupled to one side of the first flexure, deformation of the first shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a first direction; and a second shape memory alloy element coupled to a second side of the first flexure, the second side being generally opposite the first side, and deformation of the second shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 8
Dependent Claim
36 words
The apparatus of claim 6 wherein the arm portion further comprises: a second flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a second slider.
Claim 9
Dependent Claim
23 words
The apparatus of claim 7 wherein the shape memory alloy means further comprises: second shape memory alloy means coupled to the second flexure.
Claim 10
Dependent Claim
110 words
The apparatus of claim 8 wherein the second shape memory alloy means comprises: a third shape memory alloy element coupled to one side of the second flexure, deformation of the third shape memory alloy element causing the second end of the second flexure to move along the arcuate path in a first direction; and a fourth shape memory alloy element coupled to a second side of the second flexure, the second side being generally opposite the first side, and deformation of the fourth shape memory alloy element causing the second end of the second flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 11
Dependent Claim
121 words
The apparatus of claim 8 wherein the means for selectively applying thermal energy comprises: first energy means for selectively applying thermal energy to the first shape memory alloy means to cause corresponding deformation of the first shape memory alloy means causing the first flexure to deflect and move the second end of the first flexure along an arcuate path in a plane substantially transverse to the track; and second energy means for selectively applying thermal energy to the second shape memory alloy means to cause corresponding deformation of the second shape memory alloy means causing the second flexure to deflect and move the second end of the second flexure along an arcuate path in a plane substantially transverse to a track.
Claim 12
Dependent Claim
31 words
The apparatus of claim 2 wherein the shape memory alloy means is coupled at a first end to the data arm portion and at a second end to the first flexure.
Claim 13
Dependent Claim
49 words
The apparatus of claim 1 and further comprising: position indicating means for providing a position signal indicating when the transducer is tracking off center; and heat control means for selectively controlling the amount of heat applied to the shape memory alloy means as a function of the position signal.
Claim 14
Dependent Claim
50 words
The apparatus of claim 12 wherein the magnetic disk has a plurality of sectors for containing information and wherein position data is recorded on at least one of the sectors of the magnetic disk, the position data indicating a distance that the transducer is from the center of the track.
Claim 15
Dependent Claim
37 words
The apparatus of claim 13 wherein the position indicating means includes means for producing a modulated signal representing the position data which the transducer passes over as the transducer passes over the sector containing the position data.
Claim 16
Dependent Claim
25 words
The apparatus of claim 14 wherein the position indicating means further comprises: a demodulator for demodulating the modulated signal to produce a demodulated position signal.
Claim 17
Dependent Claim
80 words
The apparatus of claim 15 wherein the heat control means comprises: compensation means for compensating the demodulated position signal to provide a compensated position signal; correction means for determining a correction value based on the compensated position signal wherein the correction value represents the distance that the transducer is from the center of the track; and a heat control power supply which varies power delivered to the means for selectively applying thermal energy as a function of the correction value.
Claim 18
Dependent Claim
34 words
The apparatus of claim 1 wherein means for selectively applying thermal energy comprises: a controllable power supply, coupled to the shape memory alloy means for controlling power delivered to the shape memory alloy means.
Claim 19
Dependent Claim
43 words
The apparatus of claim 17 wherein the means for selectively applying thermal energy comprises: resistive heating element means, coupled to the controllable power supply and in thermal contact with the shape memory alloy means, for receiving power supplied by the controllable power supply.
Claim 20
Dependent Claim
44 words
The apparatus of claim 18 wherein the resistive heating element means comprises: a plurality of resistive heating elements, each in thermal contact with the shape memory alloy means, wherein power delivered to each resistive heating element by the controllable power supply is selectively controllable.
Claim 21
Dependent Claim
28 words
The apparatus of claim 19 wherein the shape memory alloy means includes a plurality of shape memory alloy elements coupled to generally opposing sides of the arm portion.
Claim 22
Dependent Claim
27 words
The apparatus of claim 20 wherein at least a single resistive heating element is in thermal contact with each of the plurality of shape memory alloy elements.
Claim 23
Dependent Claim
26 words
The apparatus of claim 21 wherein a plurality of resistive heating elements are in thermal contact with each of the plurality of shape memory alloy elements.
Claim 24
Dependent Claim
40 words
The apparatus of claim 1 and further comprising: a mechanical coupler coupling the shape memory alloy means to the arm portion such that at least a portion of the shape memory alloy means is spaced apart from the arm portion.
Claim 25
Independent Claim
176 words
An apparatus for controlling tracking of a plurality of transducers, carried by a plurality of sliders, over tracks on a plurality of magnetic disks, at least one transducer corresponding to each disk, the apparatus comprising: a plurality of arms, each having a first end for attachment to an actuator for rotating the arm, and a second end for attachment to one of the plurality of sliders, and the plurality of arms having arm portions, each arm having an arm portion extending between the first and second ends; a plurality of shape memory alloy elements, at least one shape memory alloy element coupled to each of the arm portions; and means for selectively applying thermal energy to selected shape memory alloy elements to cause corresponding deformation of the selected shape memory alloy elements causing selected deflection in the arm portions, thereby causing selected movement of the second ends along an arcuate path in a plane substantially parallel to the corresponding disk and substantially transverse to a track to position each transducer over a center of the track.
Claim 26
Independent Claim
176 words
An apparatus for controlling tracking of a plurality of transducers, carried by a plurality of sliders, over tracks on a plurality of magnetic disks, at least one transducer corresponding to each disk, the apparatus comprising: a plurality of arms, each having a first end for attachment to an actuator for rotating the arm, and a second end for attachment to one of the plurality of sliders, and the plurality of arms having arm portions, each arm having an arm portion extending between the first and second ends; a plurality of shape memory alloy elements, at least one shape memory alloy element coupled to each of the arm portions; and means for selectively applying thermal energy to selected shape memory alloy elements to cause corresponding deformation of the selected shape memory alloy elements causing selected deflection in the arm portions, thereby causing selected movement of the second ends along an arcuate path in a plane substantially parallel to the corresponding disk and substantially transverse to a track to position each transducer over a center of the track.
Claim 27
Dependent Claim
47 words
The apparatus of claim 24 wherein each arm portion comprises: a data arm portion adapted for being coupled to the actuators; and a first flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a first slider.
Claim 28
Dependent Claim
21 words
The apparatus of claim 25 wherein each data arm portion is coupled to at least one independent shape memory alloy element.
Claim 29
Dependent Claim
108 words
The apparatus of claim 26 wherein a first shape memory alloy element is coupled to one side of each data arm portion, deformation of the first shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a first direction, and wherein a second shape memory alloy element is coupled to a second side of each data arm portion, the second side being generally opposite the first side, and deformation of the second shape memory alloy element causing the second end of the first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 30
Dependent Claim
20 words
The apparatus of claim 25 wherein each first flexure is coupled to at least one independent shape memory alloy elements.
Claim 31
Dependent Claim
110 words
The apparatus of claim 28 wherein a first shape memory alloy element is coupled to one side of a corresponding first flexure, deformation of the first shape memory alloy element causing the second end of the corresponding first flexure to move along the arcuate path in a first direction, and wherein a second shape memory alloy element is coupled to a second side of the corresponding first flexure, the second side being generally opposite the first side, and deformation of the second shape memory alloy element causing the second end of the corresponding first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 32
Dependent Claim
36 words
The apparatus of claim 29 wherein each arm portion further comprises: a second flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a second slider.
Claim 33
Dependent Claim
25 words
The apparatus of claim 30 wherein at least one of the shape memory alloy elements is coupled to the second flexure of each arm portion.
Claim 34
Dependent Claim
110 words
The apparatus of claim 31 wherein a third shape memory alloy element is coupled to one side of a corresponding second flexure, deformation of the third shape memory alloy element causing the second end of the corresponding second flexure to move along the arcuate path in a first direction, and wherein a fourth shape memory alloy element is coupled to a second side of the corresponding second flexure, the second side being generally opposite the first side, and deformation of the fourth shape memory alloy element causing the second end of the corresponding second flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 35
Dependent Claim
35 words
The apparatus of claim 24 wherein the shape memory alloy elements are coupled to the arm portions such that at least a portion of each shape memory alloy element is spaced from the arm portions.
Claim 36
Dependent Claim
69 words
The apparatus of claim 24 and further comprising: arm selection means for selecting an arm to be corrected; position indicating means for providing a position signal indicating when the transducer coupled to the selected arm is tracking off center; and heat control means for selectively varying the amount of heat applied to the shape memory alloy elements coupled to the selected arm as a function of the position signal.
Claim 37
Dependent Claim
64 words
The apparatus of claim 34 wherein each magnetic disk has a plurality of sectors for containing information and wherein the position indicating means comprises: position data recorded on at least one of the sectors of the magnetic disk corresponding to the selected arm, the position data indicating a distance that the transducer coupled to the selected arm is from the center of the track.
Claim 38
Dependent Claim
38 words
The apparatus of claim 35 wherein the position signal comprises: a modulated signal representing the position data which the transducer coupled to the selected arm passes over as the transducer passes over the sector containing the position data.
Claim 39
Dependent Claim
25 words
The apparatus of claim 36 wherein the position indicating means further comprises: a demodulator for demodulating the modulated signal to produce a demodulated position signal.
Claim 40
Dependent Claim
87 words
The apparatus of claim 37 wherein the heat control means comprises: compensation means for compensating the demodulated position signal to provide compensated position signal; correction means for determining a correction value based on the compensated position signal wherein the correction value represents the distance that the transducer coupled to the selected arm is from the center of the track; and a heat control power supply which varies power delivered to the shape memory alloy element coupled to the selected arm as a function of the correction value.
Claim 41
Dependent Claim
35 words
The apparatus of claim 24 wherein the means for selectively applying thermal energy comprises: a controllable power supply, coupled to the shape memory alloy elements, for controlling power delivered to the shape memory alloy elements.
Claim 42
Dependent Claim
43 words
The apparatus of claim 39 wherein the means for selectively applying thermal energy comprises: resistive heating element means, coupled to the controllable power supply and in thermal contact with the shape memory alloy elements, for receiving power supplied by the controllable power supply.
Claim 43
Dependent Claim
44 words
The apparatus of claim 40 wherein the resistive heating element means comprises: a plurality of resistive heating elements, each in thermal contact with a shape memory alloy element, wherein power delivered to each resistive heating element by the controllable power supply is selectively controllable.
Claim 44
Dependent Claim
66 words
The apparatus of claim 41 wherein shape memory alloy elements are coupled to generally opposing sides of each of the arm portions and wherein each of the plurality of shape memory alloy elements is in thermal contact with at least a single, corresponding resistive heating element, each single resistive heating element corresponding to one of the plurality of shape memory alloy elements being independently, selectively controllable.
Claim 45
Dependent Claim
27 words
The apparatus of claim 42 wherein each of the plurality of shape memory alloy elements is in thermal contact with a plurality of corresponding resistive heating elements.
Claim 46
Independent Claim
140 words
An apparatus for repositioning a transducer, carried by a slider, over a track on a magnetic disk, comprising: an arm having a first end for attachment to an actuator for rotating the arm, a second end for attachment to the slider, and an arm portion extending between the first and second ends; positioning means coupled to the arm portion for applying force to the arm when thermal energy is applied to the positioning means and for removing the force from the arm when thermal energy is removed from the positioning means; and means for selectively applying thermal energy to the positioning means to cause corresponding contraction of the positioning means causing the arm portion to deflect and move the second end along an arcuate path to adjust position of the second end with respect to a center of the track.
Claim 47
Independent Claim
140 words
An apparatus for repositioning a transducer, carried by a slider, over a track on a magnetic disk, comprising: an arm having a first end for attachment to an actuator for rotating the arm, a second end for attachment to the slider, and an arm portion extending between the first and second ends; positioning means coupled to the arm portion for applying force to the arm when thermal energy is applied to the positioning means and for removing the force from the arm when thermal energy is removed from the positioning means; and means for selectively applying thermal energy to the positioning means to cause corresponding contraction of the positioning means causing the arm portion to deflect and move the second end along an arcuate path to adjust position of the second end with respect to a center of the track.
Claim 48
Dependent Claim
47 words
The apparatus of claim 44 wherein the arm portion comprises; a data arm portion adapted for being coupled to the actuator; and a first flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a first slider.
Claim 49
Dependent Claim
47 words
The apparatus of claim 45 wherein the positioning means comprises: a first positioning element coupled to one side of the data arm portion, contraction of the first positioning element causing the second end of the first flexure to move along the arcuate path in a first direction.
Claim 50
Dependent Claim
64 words
The apparatus of claim 46 wherein the positioning means further comprises: a second positioning element coupled to a second side of the data arm portion, the second side being generally opposite the first side, and contraction of the second positioning element causing the second end of the first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 51
Dependent Claim
43 words
The apparatus of claim 45 wherein the positioning means comprises: a first positioning element coupled to the first flexure, contraction of the first positioning element causing the second end of the first flexure to move along the arcuate path in a first direction.
Claim 52
Dependent Claim
60 words
The apparatus of claim 48 and further comprising: a second positioning element, coupled to a second side of the first flexure, the second side being generally opposite the first side, and contraction of the second positioning element causing the second end of the first flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 53
Dependent Claim
36 words
The apparatus of claim 49 wherein the arm portion further comprises: a second flexure, coupled at a first end to the data arm portion, having a second end adapted for being coupled to a second slider.
Claim 54
Dependent Claim
96 words
The apparatus of claim 50 and further comprising: a third positioning element, coupled to one side of the second flexure, contraction of the third positioning element causing the second end of the second flexure to move along the arcuate path in a first direction; and a fourth positioning element, coupled to a second side of the second flexure, the second side being generally opposite the first side, contraction of the fourth positioning element causing the second end of the second flexure to move along the arcuate path in a second direction generally opposite the first direction.
Claim 55
Dependent Claim
29 words
The apparatus of claim 45 wherein the positioning means is coupled, at a first end, to the data arm portion and, at a second end, to the first flexure.
Claim 56
Dependent Claim
46 words
The apparatus of claim 44 and further comprising: position indicating means for providing a position signal indicating when the transducer is tracking off-center; and heat control means for selectively controlling the amount of heat applied to the positioning means as a function of the position signal.
Claim 57
Dependent Claim
50 words
The apparatus of claim 53 wherein the magnetic disk has a plurality of sectors for containing information and wherein position data is recorded on at least one of the sectors of the magnetic disk, the position data indicating a distance that the transducer is from the center of the track.
Claim 58
Dependent Claim
37 words
The apparatus of claim 54 wherein the position indicating means includes means for producing a modulated signal representing the position data which the transducer passes over as the transducer passes over the sector containing the position data.
Claim 59
Dependent Claim
25 words
The apparatus of claim 55 wherein the position indicating means further comprises: a demodulator for demodulating the modulated signal to produce a demodulated position signal.
Claim 60
Dependent Claim
80 words
The apparatus of claim 56 wherein the heat control means comprises: compensation means for compensating the demodulated position signal to provide a compensated position signal; correction means for determining a correction value based on the compensated position signal wherein the correction value represents the distance that the transducer is from the center of the track; and a heat control power supply which varies power delivered to the means for selectively applying thermal energy as a function of the correction value.
Claim 61
Dependent Claim
32 words
The apparatus of claim 44 wherein the means for selectively applying thermal energy comprises: a controllable power supply, coupled to the positioning means, for controlling thermal energy delivered to the positioning means.
Claim 62
Dependent Claim
41 words
The apparatus of claim 58 wherein the means for selectively applying thermal energy comprises: resistive heating element means coupled to the controllable power supply and in thermal contact with the positioning means, for receiving power supplied by the controllable power supply.
Claim 63
Dependent Claim
42 words
The apparatus of claim 59 wherein the resistive heating element means comprises: a plurality of resistive heating elements, each in thermal contact with the positioning means, wherein power delivered to the resistive heating elements by the controllable power supply is selectively controllable.
Claim 64
Dependent Claim
45 words
The apparatus of claim 60 wherein the positioning means includes a plurality of positioning elements coupled to generally opposing sides of the arm portion and wherein at least a single resistive heating element is in thermal contact with each of the plurality of positioning elements.
Claim 65
Dependent Claim
24 words
The apparatus of claim 61 wherein a plurality of resistive heating elements are in thermal contact with each of the plurality of positioning elements.
Claim 66
Dependent Claim
36 words
The apparatus of claim 44 and further comprising: a mechanical coupler, coupling the positioning means to the arm portion such that at least a portion of the positioning means is spaced apart from the arm portion.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-04-11 | 1997-10-11 | 1998-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-11 | 2001-10-11 | 2002-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-11 | 2005-10-11 | 2006-04-12 | $7700.00 | Window Closed / Lapsed |