US4043612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bearing structure
Assignee: Ampex Systems Corp
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Filing: 1975-06-06
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Granted: 1977-08-23
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Expires: 1995-06-06
Abstract
Abstract A spiral-groove self-pressurizing bearing structure is provided with a magnetic lubricant and magnetic means to retain the lubricant in the bearing at rest. During operation, the spiral grooves pressurize and distribute the lubricant within the bearing structure, and the magnetic retention means prevents entrainment of air into the bearing, and consequent loss of lubricating action.
Inventors
- 👤 Frederic K. Orcutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:06
CPC Classifications
F; F16; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/06; F16C33/10; F16C33/1025; F16C33/103; F16C33/1035; F16C17/00; F16C17/02; F16C17/026; F16C17/10; F16C17/102; F16C17/105; F16C33/106; F16C33/107; F16C33/72; F16C33/74; F16C33/741; F16C33/743; F16C33/746; F16J; F16J15/00; F16J15/16; F16J15/40; F16J15/43; G; G11; G11B; G11B5/00; G11B5/48; G11B5/52; G11B5/53; H; H02; H02K; H02K5/00; H02K5/04; H02K5/16; H02K5/161
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
196 words
A bearing structure for a pair of relatively moving elements, characterized in that: a magnetic lubricant is disposed between said elements; and magnetic means are provided for retaining said lubricant between said pair of elements; said magnetic means including means for establishing opposite magnetic polarities in at least two portions of said structure, said portions having confronting faces defining a primary magnetic air gap flux path therebetween for focussing said magnetic fluid between said elements; said faces being inclined divergingly with respect to one another, adjacent said primary magnetic air gap flux path, to define a secondary magnetic air gap flux path serving as a reservoir, for receiving excess magnetic lubricant from said primary air gap when the volume defined between said elements decreases or the volume of said lubricant increases, and for supplying magnetic lubricant to said primary air gap when the volume defined between said elements increases or the volume of said lubricant decreases; and at least one of said elements is formed with pumping grooves for receiving magnetic lubricant from at least said secondary reservoir air gap and for pressurizing and distributing said lubricant between said elements during relative movement of the elements.
Claim 2
Dependent Claim
196 words
A bearing structure for a pair of relatively moving elements, characterized in that: a magnetic lubricant is disposed between said elements; and magnetic means are provided for retaining said lubricant between said pair of elements; said magnetic means including means for establishing opposite magnetic polarities in at least two portions of said structure, said portions having confronting faces defining a primary magnetic air gap flux path therebetween for focussing said magnetic fluid between said elements; said faces being inclined divergingly with respect to one another, adjacent said primary magnetic air gap flux path, to define a secondary magnetic air gap flux path serving as a reservoir, for receiving excess magnetic lubricant from said primary air gap when the volume defined between said elements decreases or the volume of said lubricant increases, and for supplying magnetic lubricant to said primary air gap when the volume defined between said elements increases or the volume of said lubricant decreases; and at least one of said elements is formed with pumping grooves for receiving magnetic lubricant from at least said secondary reservoir air gap and for pressurizing and distributing said lubricant between said elements during relative movement of the elements.
Claim 3
Dependent Claim
38 words
A bearing structure as described in claim 1, and further characterized in that: one of said elements has a recess presenting a surface of revolution within which a conforming portion of the other element fits for relative rotation.
Claim 4
Dependent Claim
34 words
A bearing structure as described in claim 2, and further characterized in that: said elements are magnetized to provide opposite attracting poles, concentrically arranged one in each element, at the opening of said recess.
Claim 5
Dependent Claim
78 words
A bearing structure as described in claim 2, and further characterized in that: said recess and the conforming portion of said other element are right-circular-cylindrical in form defining a shaft and a journal bearing block therefor; said pumping grooves are helical on the sides of one of said elements within said recess; and said grooves are directed to pump toward the mid-axial portion of said recess in said block when said shaft is rotating in a predetermined direction.
Claim 6
Dependent Claim
97 words
A bearing structure as described in claim 2, and further characterized in that: said recess and the conforming portion of said other element are right-circular-cylindrical in form defining a shaft and a combination thrust and journal bearing block therefor; and said pumping grooves are spiral on the circular end of one of said elements within said recess, and helical on the sides of said one element within said recess, and all of said grooves are directed to pump toward the central end portion of said shaft and recess when said shaft is rotating in a predetermined direction.
Claim 7
Dependent Claim
85 words
A bearing structure as described in claim 2, and further characterized in that: said recess and the conforming portion of said other element have confronting surfaces that are at least in part inclined with respect to both the axis of said relative rotation and a plane normal to said axis, so as to define a combination thrust and journal bearing; and means are provided for urging said elements together in the direction of said axis to provide centering action in both rotating and non-rotating modes.
Claim 8
Dependent Claim
77 words
A bearing structure as described in claim 2, and further characterized in that: said recess and the conforming portion of said other element are conical in shape, defining a shaft and a combination thrust and journal bearing block therefor; and said pumping grooves are helical on the conical portion of one of said elements, so as to pump toward the central end portion of said shaft and recess when said shaft is rotating in a predetermined direction.
Claim 9
Dependent Claim
167 words
A bearing structure as described in claim 7, and further characterized in that: said recess and the conforming portion of said shaft are frustro-conical, the conical converging surface of said recess being defined by a non-magnetic body portion of said block; the base portion of said conical converging surface of said recess being defined by a first pole-piece supported by said block body portion and encircling said shaft so as to form an opening into said recess; the frustrum end of said frusto-conical recess being defined by a second pole-piece supported by said block body portion and extending radially from the axis of rotation of said shaft; and said magnetic means including at least two bar permanent magnets similarly oriented and aligned parallel to said axis spaced circumferentially thereabout, said magnets being supported by said block body portion and engaging said pole pieces at either end; said shaft being of magnetically permeable material, so as to define a return circuit path for the field of said magnets.
Claim 10
Dependent Claim
57 words
A bearing structure as described in claim 8, and further characterized in that: said first pole piece is chamfered to define a bevel surface encircling said shaft and converging radially inwardly toward the shaft end, so that said ferromagnetic lubricant protruding from said opening tends to concentrate at the smallest interior diameter of said first pole piece.
Claim 11
Dependent Claim
168 words
A bearing structure as described in claim 9, and further characterized in that: said shaft is frustro-conical at both ends, and two of said blocks are provided supporting said shaft at each end; one of said bearing blocks being fixed and the other being slidable in the axial direction of said shaft; and means are provided for urging said slidable bearing block toward said fixed bearing block; whereby said blocks are urged together when said shaft is stopped, to effect substantial supporting and centering engagement of the conical surfaces of said shaft and blocks, with the excess of said ferrofluidic lubricant being squeezed out to form a meniscus between said shaft and the chamfered surfaces of said first pole pieces, but yet upon rotation of said shaft in said predetermined direction, said fluid is pumped under substantial pressure into said recesses to force said blocks somewhat apart and to support the load of said shaft while lubricating the rotation thereof, and all without entraining air into the bearings.
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) | 1980-08-22 | 1981-02-21 | 1981-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-22 | 1985-02-21 | 1985-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-22 | 1989-02-21 | 1989-08-23 | $7700.00 | Window Closed / Lapsed |