US5117589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adjustable transfer tool for lapping magnetic head sliders
Assignee: Western Digital Technologies Inc
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Filing: 1991-04-01
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Granted: 1992-06-02
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Expires: 2011-04-01
Abstract
Abstract An adjustable transfer tool is used to compensate for row bow during lapping a bar or a row of magnetic head sliders. The adjustable transfer tool enables establishing uniform and substantially precise throat heights for a multiplicity of thin film transducers disposed on said sliders. To allow the desired adjustment, the transfer tool incorporates slot means by which the shape of the surface of the tool on which the bar of sliders is mounted can be modified so that the slider transducers assume a collinear array across its entire length for the lapping process. Adjustment is accomplished by manual means, such as by a screw or a tapered pipe plug, or by electrical means, such as a piezoelectric actuator, in conjunction with a computer or microprocessor.
Inventors
- 👤 Peter G. Bischoff
- 👤 Robert A. Cole
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:11
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3163
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
290 words
An adjustable transfer tool for lapping magnetic head sliders on which thin film transducers are deposited comprising: a tool body for supporting a bar of material from which said magnetic head sliders are to be configured, each of said sliders having at least one transducer disposed thereon, said transducers having a transducing gap at a surface to be lapped; said tool body being formed with first, second and third sections, said first section having a top surface for accommodating a magnetic head slider bar; a substantially U-shaped slot formed between said sections, one leg of such slot being disposed between the bottom of said first section and the top of said second section, and a second leg of said slot being disposed between the bottom of said second section and the top of said third section, and a base connecting said legs disposed between said first and third sections; said second section configured substantially as a finger disposed between the legs of said U-shaped slot, said second section having a free end in juxtaposition to said base, a first body part at the other end of such second section for connecting said second section approximately to the center of said first section, a second body part connecting other end of said second section to a point on said third section displaced from the center of said third section; adjustment means for applying a displacement force at said free end of said second section so that second section operates as a lever for adjusting the curvature of said top surface of said first body section and for correcting for row bow of said head slider bar so that the throat height of said transducers are effectively controlled to very close tolerances.
Claim 2
Dependent Claim
290 words
An adjustable transfer tool for lapping magnetic head sliders on which thin film transducers are deposited comprising: a tool body for supporting a bar of material from which said magnetic head sliders are to be configured, each of said sliders having at least one transducer disposed thereon, said transducers having a transducing gap at a surface to be lapped; said tool body being formed with first, second and third sections, said first section having a top surface for accommodating a magnetic head slider bar; a substantially U-shaped slot formed between said sections, one leg of such slot being disposed between the bottom of said first section and the top of said second section, and a second leg of said slot being disposed between the bottom of said second section and the top of said third section, and a base connecting said legs disposed between said first and third sections; said second section configured substantially as a finger disposed between the legs of said U-shaped slot, said second section having a free end in juxtaposition to said base, a first body part at the other end of such second section for connecting said second section approximately to the center of said first section, a second body part connecting other end of said second section to a point on said third section displaced from the center of said third section; adjustment means for applying a displacement force at said free end of said second section so that second section operates as a lever for adjusting the curvature of said top surface of said first body section and for correcting for row bow of said head slider bar so that the throat height of said transducers are effectively controlled to very close tolerances.
Claim 3
Dependent Claim
34 words
An adjustable transfer tool as in claim 1, wherein said adjustment means is a threaded screw passing through said third section and bearing against said second section for controllably rotating said second lever section.
Claim 4
Dependent Claim
24 words
An adjustable transfer tool as in claim 2, wherein the displacement provided by said threaded screw is approximately 0.0000035 inch per degree of rotation.
Claim 5
Dependent Claim
39 words
An adjustable transfer tool as in claim 1, wherein said adjustment means is a movable tapered pipe plug disposed within said second leg of said slot and between said second and third sections for controllably rotating said second section.
Claim 6
Dependent Claim
28 words
An adjustable transfer tool as in claim 4, wherein the displacement provided by said pipe plug is approximately 0.0000006 inch per degree of rotation of said pipe plug.
Claim 7
Dependent Claim
48 words
An adjustable transfer tool as in claim 1, further including a second slot formed between said first and third sections adjacent to said other end of said second section, wherein said second section acts as a lever with its fulcrum between said U-shaped slot and said second slot.
Claim 8
Dependent Claim
40 words
An adjustable transfer tool as in claim 1, wherein said adjustable means provides an applied force which results in an upward displacement of said lever with a corresponding downward displacement substantially at the center of the magnetic head slider bar.
Claim 9
Dependent Claim
122 words
An adjustable transfer tool useful for lapping magnetic head sliders on which thin film transducers are deposited comprising: a tool body for supporting a bar of material from which magnetic head sliders are to be configured, each of said sliders having at least one transducer disposed thereon, said transducers having a magnetic gap at a surface to be lapped; a configured slot formed in said body; means for varying the configuration of said slot and the contour of said surface so that said surface is adjusted to cause the array of sliders and transducers thereon to become collinear during lapping whereby the throat height of said transducers is effectively controlled to be substantially uniform, wherein said adjustment means is a piezoelectric actuator.
Claim 10
Dependent Claim
122 words
An adjustable transfer tool useful for lapping magnetic head sliders on which thin film transducers are deposited comprising: a tool body for supporting a bar of material from which magnetic head sliders are to be configured, each of said sliders having at least one transducer disposed thereon, said transducers having a magnetic gap at a surface to be lapped; a configured slot formed in said body; means for varying the configuration of said slot and the contour of said surface so that said surface is adjusted to cause the array of sliders and transducers thereon to become collinear during lapping whereby the throat height of said transducers is effectively controlled to be substantially uniform, wherein said adjustment means is a piezoelectric actuator.
Claim 11
Dependent Claim
22 words
An adjustable transfer tool as in claim 8, wherein said slot means comprises a T-shaped slot in which said actuator is positioned.
Claim 12
Dependent Claim
28 words
An adjustable transfer tool as in claim 8, including means coupled to said actuator for providing voltage signals to said actuator to vary the height of said actuator.
Claim 13
Dependent Claim
22 words
An adjustable transfer tool as in claim 8, wherein said actuator comprises a plurality of alternating piezoelectric crystal layers and conductive layers.
Claim 14
Dependent Claim
20 words
An adjustable transfer tool as in claim 11, wherein alternate one of said conductive layers are coupled to ground potential.
Claim 15
Dependent Claim
22 words
An adjustable transfer tool as in claim 12, wherein said piezoelectric actuator operates through an intermediate lever for increasing the resultant displacement.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-02 | 1995-12-02 | 1996-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-02 | 1999-12-02 | 2000-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-02 | 2003-12-02 | 2004-06-02 | $7700.00 | Window Closed / Lapsed |