US3678482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple surface fluid film bearing
Assignee: Unisys Corp
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Filing: 1970-08-26
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Granted: 1972-07-18
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Expires: 1990-08-26
Abstract
Abstract A magnetic memory system having a recording head adjacent a movable disk is described wherein the recording head is separated from the disk by a fluid bearing. In a preferred embodiment, the bearing comprises a taper land bearing having a main bearing face preceded by a converging bearing face. A narrow slot provides a hydrodynamic separation between the trailing edge of the main face and the leading edge of a satellite face coplanar with the main bearing face. A diverging face is provided aft of the satellite face. In operation the recording head is retracted until the disk is up to its usual rotational speed, and then the head is advanced toward the disk to its final floating position in the order of 30 microinches from the surface. The satellite face and diverging face cooperate during the transitional ''''landing'''' of the recording head to produce a fluid film force that pivots the recording head to its final floating position without contact between the disk and head.
Inventors
- 👤 Shahbuddin A Billawala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:30
CPC Classifications
F; F16; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/06; F16C33/10; G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/60; G11B5/6005; G11B5/6011; G11B5/6064; G11B5/6082
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
168 words
A fluid film bearing member movable between a first position sufficiently remote from a second member movable relative thereto that fluid film forces are negligible and a second position sufficiently near the second member that fluid film forces between the two members are substantial comprising: a main bearing portion having a leading edge and a trailing edge on the bearing member and adapted to float adjacent the second member in the second position for generating a principal portion of fluid film force while in the second position; and means for generating a larger fluid film forcE than the main bearing portion at an intermediate position during transition of the bearing member between the first position and the second position comprising a satellite bearing portion at least partly hydrodynamically separated from and aft of the trailing edge of the main bearing portion and adapted to float adjacent the second bearing member in the second position for generating a minor portion of fluid film force while in the second position.
Claim 2
Dependent Claim
168 words
A fluid film bearing member movable between a first position sufficiently remote from a second member movable relative thereto that fluid film forces are negligible and a second position sufficiently near the second member that fluid film forces between the two members are substantial comprising: a main bearing portion having a leading edge and a trailing edge on the bearing member and adapted to float adjacent the second member in the second position for generating a principal portion of fluid film force while in the second position; and means for generating a larger fluid film forcE than the main bearing portion at an intermediate position during transition of the bearing member between the first position and the second position comprising a satellite bearing portion at least partly hydrodynamically separated from and aft of the trailing edge of the main bearing portion and adapted to float adjacent the second bearing member in the second position for generating a minor portion of fluid film force while in the second position.
Claim 3
Dependent Claim
57 words
A fluid film bearing member as defined in claim 1 wherein the main bearing portion comprises: a main bearing face having a leading edge and a trailing edge; and a converging bearing face having a trailing edge coincident with the leading edge of the main bearing face, the converging face being angulated relative to the main face.
Claim 4
Dependent Claim
70 words
A fluid film bearing member as defined in claim 2 wherein the satellite bearing portion comprises a satellite bearing face having a leading edge and a trailing edge and coplanar with the main bearing face of the main bearing portion; and a diverging bearing face having a leading edge at least in part coincident with the trailing edge of the satellite bearing face and angulated relative to the satellite face.
Claim 5
Dependent Claim
36 words
A fluid film bearing member as defined in claim 3 wherein the diverging bearing face is at a greater angle from the satellite bearing face than the converging bearing face is from the main bearing face.
Claim 6
Dependent Claim
59 words
A fluid film bearing member as defined in claim 1 wherein the satellite bearing portion includes a bearing face having a leading edge displaced laterally from the main bearing face in a direction transverse to the direction of relative motion of the baring member and second member for enhancing roll stability and influencing roll attitude of the bearing member.
Claim 7
Dependent Claim
163 words
A magnetic memory system comprising: a recording head having a leading edge and a trailing edge; a magnetic memory surface movable relative to the recording head; the recording head being movable between a retracted position relatively remote from the memory surface and a final floating position at a relatively small predetermined distance from the memory surface, a main bearing surface on the recording head arranged to float adjacent the memory surface when the head is in the final floating position and for generating a principal portion of fluid film force while the recording head is in the final floating position; and means for applying a substantial moment to the recording head in a position intermediate between the retracted and floating positions, the moment tending to raise the trailing edge and lower the leading edge of the recording head relative to the memory surface, comprising a satellite bearing portion having at least a portion aft of the main bearing surface and hydrodynamically separated therefrom.
Claim 8
Dependent Claim
163 words
A magnetic memory system comprising: a recording head having a leading edge and a trailing edge; a magnetic memory surface movable relative to the recording head; the recording head being movable between a retracted position relatively remote from the memory surface and a final floating position at a relatively small predetermined distance from the memory surface, a main bearing surface on the recording head arranged to float adjacent the memory surface when the head is in the final floating position and for generating a principal portion of fluid film force while the recording head is in the final floating position; and means for applying a substantial moment to the recording head in a position intermediate between the retracted and floating positions, the moment tending to raise the trailing edge and lower the leading edge of the recording head relative to the memory surface, comprising a satellite bearing portion having at least a portion aft of the main bearing surface and hydrodynamically separated therefrom.
Claim 9
Dependent Claim
81 words
A magnetic memory system as defined in claim 6 wherein the satellite bearing comprises: a satellite plane bearing face having a leading edge and a trailing edge and a satellite diverging bearing face having a leading edge at least partly coincident with the trailing edge of the satellite bearing face, the satellite diverging bearing face being angulated relative to the satellite plane bearing face for diverging from the magnetic memory surface while the recording head is in the final floating position.
Claim 10
Dependent Claim
36 words
A magnetic memory system as defined in claim 7 further comprising: a plurality of magnetic recording transducers, each of the transducers having a recording gap substantially aligned with the trailing edge of the satellite bearing face.
Claim 11
Dependent Claim
44 words
A magnetic memory system as defined in claim 6 wherein the satellite bearing portion is substantially longer in a direction transverse to the direction of movement relative to the memory surface than it is in a direction parallel to the direction of relative movement.
Claim 12
Dependent Claim
65 words
A magnetic memory system as defined in claim 6 wherein the main bearing surface comprises a taper land bearing having a plane main bEaring face having a leading edge and a trailing edge; and a plane converging bearing face having a trailing edge coincident with the leading edge of the main bearing face, the converging bearing face being angulated relative to the main bearing face.
Claim 13
Dependent Claim
77 words
A magnetic memory system as defined in claim 10 wherein the satellite bearing portion comprises a satellite plane bearing face having a leading edge and a trailing edge, the leading edge being hydrodynamically separated from the trailing edge of the main bearing face; and a satellite diverging bearing face having a leading edge at least in part coincident with the trailing edge of the satellite bearing face, the diverging face being angulated relative to the satellite face.
Claim 14
Dependent Claim
36 words
A magnetic memory system as defined in claim 11 further comprising: a plurality of magnetic transducers, each of the transducers having a magnetic recording gap approximately aligned with the trailing edge of the satellite bearing face.
Claim 15
Dependent Claim
33 words
A magnetic memory system as defined in Claim 12 further comprising: a recessed region surrounding each of the transducers sufficiently remote from the bearing faces to be substantially free of fluid film forces.
Claim 16
Dependent Claim
89 words
A magnetic memory system as defined in claim 6 further comprising resilient means for applying a moment to the recording head, the applied moment being negligible while the recording head is in the retracted position and substantial when the recording head is in the final floating position and wherein the moment applied to the recording head by the satellite bearing position when the recording head is in a position intermediate between the retracted and floating positions is at least as great as the moment applied by the resilient means.
Claim 17
Dependent Claim
115 words
A recording head comprising: a fluid film bearing surface portion adapted to float adjacent the magnetic memory surface on a fluid film and having: a first bearing face having a trailing edge; and a second bearing face having at least a portion of leading edge coincident with the trailing edge of the first bearing face, the second bearing face being angulated relative to the first bearing face; a recessed region within the fluid film bearing surface; and a magnetic transducer mounted in the recording head within the recessed region and having a magnetic recording gap substantially aligned with the trailing edge of the first bearing face, and substantially flush with the fluid film bearing surface.
Claim 18
Dependent Claim
115 words
A recording head comprising: a fluid film bearing surface portion adapted to float adjacent the magnetic memory surface on a fluid film and having: a first bearing face having a trailing edge; and a second bearing face having at least a portion of leading edge coincident with the trailing edge of the first bearing face, the second bearing face being angulated relative to the first bearing face; a recessed region within the fluid film bearing surface; and a magnetic transducer mounted in the recording head within the recessed region and having a magnetic recording gap substantially aligned with the trailing edge of the first bearing face, and substantially flush with the fluid film bearing surface.
Claim 19
Dependent Claim
40 words
A recording head as defined in claim 15 wherein the bearing surface further comprises: a third bearing face coplanar with the first bearing face and having a trailing edge hydrodynamically separated from the leading edge of the first bearing face.
Claim 20
Dependent Claim
40 words
A recording head as defined in claim 16 wherein the bearing surface further comprises: a fourth bearing face having a trailing edge coincident with the leading edge of the third bearing face and angulated relative thereto by a small angle.
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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) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |