US3759626A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bearing arrangement for molecular and turbo molecular pumps
Assignee: PFEIFFER A GmbH
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Filing: 1971-10-22
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Granted: 1973-09-18
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Expires: 1991-10-22
Abstract
Abstract In molecular and turbo molecular pumps a bearing arrangement is provided for the member which rotates the rotor discs of the pump and includes a pair of axially spaced bearing heads each supporting a bearing for the rotating member. The bearing heads are supported from the pump casing by radially extending disclike spring members which have a spring stiffness in the radial direction which is greater than the spring stiffness in the axial direction. Further, one of the bearing heads is biased toward the other by an axially arranged spring so that the play of the bearings is made zero. Oil is supplied to the bearings and is prevented from entering the space containing the stator and rotor discs. Damping elements are provided in association with the radially extending spring members or, alternatively, damping material is coated on the spring members.
Inventors
- 👤 W Becker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:31
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/05; F04D29/056; F04D29/059; F04D19/00; F04D19/02; F04D19/04; F04D19/042; F04D25/00; F04D25/02; F04D25/06; F04D25/0606; F04D29/051; F04D29/06; F04D29/063; F04D29/66; F04D29/661; F04D29/668; F16; F16C; F16C27/00; F16F; F16F1/00; F16F1/02; F16F1/025; F16F1/027; F16C2360/00; F16C2360/44; F16C2360/45
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
199 words
In molecular and turbo molecular pumps comprising a casing, a plurality of alternating spaced rotor discs and stator discs disposed in said casing, means for rotating said rotor discs including an axially elongated rotating member, and a bearing assembly for rotatably supporting said rotating member, wherein the improvement comprises that said bearing assembly includes a pair of axially spaced bearing heads spaced inwardly from said casing, a bearing supported within each of said bearing heads and arranged for rotatably supporting said rotating member, first spring means secured to and extending radially outwardly from said bearing head, second spring means biasing at least one of said bearing heads in the axial direction toward the other said bearing heaD, said first spring means has a greater spring stiffness in the radial direction as compared to its spring stiffness in the axial direction, said first spring means for each said bearing head comprises a pair of axially spaced radially extending spring members each secured along its radially inner edge to said bearing head, a casing ring laterally enclosing and disposed radially outwardly from each said bearing head, and the radially outer edges of said spring members being secured to said casing ring.
Claim 2
Dependent Claim
199 words
In molecular and turbo molecular pumps comprising a casing, a plurality of alternating spaced rotor discs and stator discs disposed in said casing, means for rotating said rotor discs including an axially elongated rotating member, and a bearing assembly for rotatably supporting said rotating member, wherein the improvement comprises that said bearing assembly includes a pair of axially spaced bearing heads spaced inwardly from said casing, a bearing supported within each of said bearing heads and arranged for rotatably supporting said rotating member, first spring means secured to and extending radially outwardly from said bearing head, second spring means biasing at least one of said bearing heads in the axial direction toward the other said bearing heaD, said first spring means has a greater spring stiffness in the radial direction as compared to its spring stiffness in the axial direction, said first spring means for each said bearing head comprises a pair of axially spaced radially extending spring members each secured along its radially inner edge to said bearing head, a casing ring laterally enclosing and disposed radially outwardly from each said bearing head, and the radially outer edges of said spring members being secured to said casing ring.
Claim 3
Dependent Claim
21 words
In molecular and turbo molecular pumps, as set forth in claim 1, wherein said spring members are flat disc-shaped plate springs.
Claim 4
Dependent Claim
50 words
In molecular and turbo molecular pumps, as set forth in claim 1, wherein said spring members are plate springs having a curved surface in a radially extending plane through the axis of said rotating member with the curved surface extending outwardly from the transversely extending surface of said bearing head.
Claim 5
Dependent Claim
22 words
In molecular and turbo molecular pumps, as set forth in claim 1, wherein damping means are associated with said first spring means.
Claim 6
Dependent Claim
36 words
In molecular and turbo molecular pumps, as set forth in claim 4, wherein said damping means comprises a damping element located between said spring members and extending radially between said bearing head and said casing ring.
Claim 7
Dependent Claim
30 words
In molecular and turbo molecular pumps, as set forth in claim 4, wherein said damping means comprises a coating of damping material deposited on the surfaces of said spring members.
Claim 8
Dependent Claim
28 words
In molecular and turbo molecular pumps, as set forth in claim 6, wherein said damping material is a metal selected from the group consisting of lead and indium.
Claim 9
Dependent Claim
22 words
In molecular and turbo molecular pumps, as set forth in claim 6, wherein said damping material is a resilient synthetic damping material.
Claim 10
Dependent Claim
95 words
In molecular and turbo molecular pumps, as set forth in claim 1, wherein the axis of said rotating member is arranged horizontally and each of said bearing heads is located spaced outwardly from an opposite end of said stator and rotor discs, said spring members are plate members extending between said bearing head and said casing ring, said second spring means comprises an axially extending helical spring bearing against one of said bearing heads on the side thereof opposite said bearing supported therein, and an adjustable abutment supporting the other one of said bearing heads.
Claim 11
Dependent Claim
58 words
In molecular and turbo molecular pumps, as set forth in claim 9, including means for supplying lubricating oil to and removing it from said bearings, and vapor baffles positioned between said bearings and said stator and rotor discs and extending across said casing for preventing oil vapor from penetrating into the space containing said stator and rotor discs.
Claim 12
Dependent Claim
87 words
In molecular and turbo molecular pumps, as set forth in claim 1, wherein the axis of said rotating member is arranged vertically, and extends from one end of said stator and rotor discs, said spring members are flat disc-shaped springs, said second spring means comprises an axially extending helical spring bearing against the one of said bearing heads more remote from said stator and rotor discs and biasing said rotating member toward said stator and rotor discs, and an abutment for supporting the other said bearing head.
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) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |