Patent US3826588A successfully refreshed from Google Patents.
US3826588A
Expired / Lapsed
US
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Turbomolecular vacuum pump
Assignee: Leybold Heraeus Verwaltung GmbH
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Filing: 1973-06-19
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Granted: 1974-07-30
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Expires: 1993-06-19
Abstract
Abstract In a turbomolecular vacuum pump which has axially spaced pump stages each formed of a stator blade wheel and a cooperating rotor blade wheel, the pitch angle of the blades in at least one pump stage increases in a direction radially outwardly from the blade ends attached to the pump rotor or pump stator for maintaining the compression ratio in that pump stage at least approximately constant in the radial direction.
Inventors
- 👤 R Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:48
CPC Classifications
F; F04; F04D; F04D19/00; F04D19/02; F04D19/04; F04D19/042; F04D29/00; F04D29/26; F04D29/32; F04D29/321; F04D29/324; F04D29/40; F04D29/52; F04D29/54; F04D29/541; F04D29/542; F04D29/544
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
217 words
In a turbomolecular vacuum pump having an axis, a high vacuum side, a stator, a plurality of axially spaced stator blade wheels carried by said stator, each stator blade wheel being formed of a plurality of circumferentially spaced stator blades each having one end attached to said stator and each extending in a radial direction with respect to said axis, a rotor arranged axially coextensive with said stator, a plurality of axially spaced rotor blade wheels carried by said rotor, each rotor blade wheel being formed of a plurality of circumferentially spaced rotor blades each having one end attached to said rotor and each extending in a radial direction, each blade having a pitch angle defined by the inclination of the blade to the plane of the blade wheel, said stator blade wheels being in an interleaving relationship with said rotor blade wheels, each stator blade wheel forming a pump stage with an adjacent, cooperating rotor blade wheel, the improvement comprising the arrangement of the blades in at least one pump stage, wherein the pitch angle of the blades in said at least one pump stage increases in a direction radially outwardly from their respective attached end for maintaining the compression ratio in said at least one pump stage at least approximately constant in the radial direction.
Claim 2
Dependent Claim
217 words
In a turbomolecular vacuum pump having an axis, a high vacuum side, a stator, a plurality of axially spaced stator blade wheels carried by said stator, each stator blade wheel being formed of a plurality of circumferentially spaced stator blades each having one end attached to said stator and each extending in a radial direction with respect to said axis, a rotor arranged axially coextensive with said stator, a plurality of axially spaced rotor blade wheels carried by said rotor, each rotor blade wheel being formed of a plurality of circumferentially spaced rotor blades each having one end attached to said rotor and each extending in a radial direction, each blade having a pitch angle defined by the inclination of the blade to the plane of the blade wheel, said stator blade wheels being in an interleaving relationship with said rotor blade wheels, each stator blade wheel forming a pump stage with an adjacent, cooperating rotor blade wheel, the improvement comprising the arrangement of the blades in at least one pump stage, wherein the pitch angle of the blades in said at least one pump stage increases in a direction radially outwardly from their respective attached end for maintaining the compression ratio in said at least one pump stage at least approximately constant in the radial direction.
Claim 3
Dependent Claim
30 words
A turbomolecular vacuum pump as defined in claim 1, wherein solely the blades of the pump stages at the high vacuum side of the pump have radially varying pitch angles.
Claim 4
Dependent Claim
27 words
A turbomolecular vacuum pump as defined in claim 1, wherein said radially outwardly increasing pitch angle varies continuousLy at least along subsequent length portions of the blade.
Claim 5
Dependent Claim
69 words
A turbomolecular vacuum pump as defined in claim 1, wherein the degree of overlap defined by the ratio of the distance between corresponding points on adjacent blades of the same blade wheel as measured along a circle concentric with said blade wheel, to the width of one of said blades as measured along said concentric circle, is approximately constant in the radial direction in at least one pump stage.
References Cited (Backward Citations)
US3748055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-29 | 1978-01-28 | 1978-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-29 | 1982-01-28 | 1982-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-29 | 1986-01-28 | 1986-07-30 | $7700.00 | Window Closed / Lapsed |