Patent US3701535A successfully refreshed from Google Patents.
US3701535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contact-free hydrostatic seal
Assignee: Klein Schanzlin and Becker AG
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Filing: 1970-04-27
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Granted: 1972-10-31
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Expires: 1990-04-27
Abstract
Abstract A contact-free hydrostatic seal wherein a rotary first annular sealing element defines with a second annular sealing element a gap for leak fluid. The second sealing element is biased toward the first sealing element by closing springs which tend to reduce the width of the gap. A pump delivers fluid into the gap to oppose the action of closing springs and to prevent direct contact between the sealing elements. When the pressure of fluid drops to such an extent that it can be overcome by the bias of closing springs, a safety device becomes operative to oppose such bias and to hold the second sealing element away from the first sealing element. The safety device includes a lever which is pivoted into engagement with the second sealing element by one or more strong springs when such strong spring or springs overcome the fluid pressure at a time when the fluid pressure is too low to prevent the closing springs from moving the second sealing element into frictional engagement with the first sealing element.
Inventors
- 👤 Dieter Born
- 👤 Peter Stech
- 👤 Werner Huebner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:19
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/40; F16J15/34; F16J15/3436; F16J15/346
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
220 words
A contact-free hydrostatic seal for controling leakage of fluids between stationary and moving components comprising a rotary first sealing element; a second sealing element coaxial with and defining with said first sealing element a gap; biasing means urging one of said sealing elements axially toward the other sealing element to reduce the width of said gap; a feed for conveying fluid into said gap under pressure which normally suffices to oppose said biasing means and to maintain said sealing elements out of contact with each other; and safety means for opposing said biasing means in response to a predetermined drop in fluid pressure so as to maintain said elements out of contact when the pressure of fluid supplied by said feed is insufficient to prevent excessive reduction in the width of said gap, said safety means comprising a shifting member movable into engagement with said one sealing element to shift the latter away from said other sealing element, piston means movable against said shifting means to move the latter into engagement with said one sealing element, and resilient means biasing said piston means against said shifting means, said piston means being subjected to the pressure of fluid supplied by said feed and such fluid opposing the bias of said resilient means when its pressure suffices to oppose said biasing means.
Claim 2
Dependent Claim
220 words
A contact-free hydrostatic seal for controling leakage of fluids between stationary and moving components comprising a rotary first sealing element; a second sealing element coaxial with and defining with said first sealing element a gap; biasing means urging one of said sealing elements axially toward the other sealing element to reduce the width of said gap; a feed for conveying fluid into said gap under pressure which normally suffices to oppose said biasing means and to maintain said sealing elements out of contact with each other; and safety means for opposing said biasing means in response to a predetermined drop in fluid pressure so as to maintain said elements out of contact when the pressure of fluid supplied by said feed is insufficient to prevent excessive reduction in the width of said gap, said safety means comprising a shifting member movable into engagement with said one sealing element to shift the latter away from said other sealing element, piston means movable against said shifting means to move the latter into engagement with said one sealing element, and resilient means biasing said piston means against said shifting means, said piston means being subjected to the pressure of fluid supplied by said feed and such fluid opposing the bias of said resilient means when its pressure suffices to oppose said biasing means.
Claim 3
Dependent Claim
44 words
A hydrostatic seal as defined in claim 1, wherein said shifting member is a lever and said piston comprises an adjustable portion which engages with said lever to pivot the latter against said one sealing element when said resilient means overcomes the fluid pressure.
Claim 4
Dependent Claim
63 words
A hydrostatic seal as defined in claim 1, further comprising a housing for said piston means, a bellows affixed to said piston means and said housing and defining therewith a chamber in communication with said feed, said piston means having a shoulder provided in said chamber and acted upon by fluid admitted by said feed to oppose the bias of said resilient means.
Claim 5
Dependent Claim
50 words
A hydrostatic seal as defined in claim 1, wherein said biasing means comprises at least one first spring operating between a carrier for said one sealing element and said one sealing element, and said resilient means comprises at least one second spring operating between said carrier and said piston means.
Claim 6
Dependent Claim
32 words
A hydrostatic seal as defined in claim 1, wherein saId one sealing element is said second sealing element and wherein said first sealing element rotates with reference to said second sealing element.
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) | 1975-10-31 | 1976-05-01 | 1976-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-31 | 1980-05-01 | 1980-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-31 | 1984-05-01 | 1984-10-31 | $7700.00 | Window Closed / Lapsed |