Patent US3857544A successfully refreshed from Google Patents.
US3857544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically operated relief valves
Assignee: Northrop Grumman Properties Ltd
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Filing: 1972-12-15
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Granted: 1974-12-31
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Expires: 1992-12-15
Abstract
Abstract An electrically-operated pressure relief valve has a closure member which can be urged open by pressure at the valve inlet. A cross-member is secured to the shaft of a torque motor for pivotal movement within the valve body. One end of said crossmember engages a stem of said closure member, and the crossmember is also engaged by a spring which rotates the shaft to urge the closure member shut. The torque motor is energisable to rotate the shaft against the spring to open the valve. The bias applied by the spring is variable and the distance between the shaft and the engagement of the cross-member with the valve stem is also variable.
Inventors
- 👤 R Rigby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:44
CPC Classifications
F; F16; F16K; F16K31/00; F16K31/02; F02; F02C; F02C9/00; F02C9/16; G; G05; G05D; G05D16/00; G05D16/20; G05D16/2093; G05D16/2095; G05D16/2097
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
142 words
A pressure relief valve comprising a housing having an inlet and an outlet, a closure member movable in response to a pressure in said inlet to open the valve, a torque motor, a linkage operatively connecting a shaft of said torque motor to said closure member, said shaft being rotatable in a direction to open the valve in response to an electrical control signal, biasing means urging the shaft to rotate in a direction to shut the valve and means for adjustably varying movement of the closure member in response to a given angular movement of the shaft, said linkage including a part secured to said shaft for rotation therewith and a stem extending transversely of the axis of said shaft and engaging said part and said closure member, the axis of said stem being spaced from the axis of said shaft.
Claim 2
Dependent Claim
142 words
A pressure relief valve comprising a housing having an inlet and an outlet, a closure member movable in response to a pressure in said inlet to open the valve, a torque motor, a linkage operatively connecting a shaft of said torque motor to said closure member, said shaft being rotatable in a direction to open the valve in response to an electrical control signal, biasing means urging the shaft to rotate in a direction to shut the valve and means for adjustably varying movement of the closure member in response to a given angular movement of the shaft, said linkage including a part secured to said shaft for rotation therewith and a stem extending transversely of the axis of said shaft and engaging said part and said closure member, the axis of said stem being spaced from the axis of said shaft.
Claim 3
Dependent Claim
19 words
A valve as claimed in claim 1 which includes a linkage operatively connecting said shaft and said closure member.
Claim 4
Dependent Claim
27 words
A valve as claimed in claim 1 in which said part includes means for varying the spacing of the axes of said shaft and said closure member.
Claim 5
Dependent Claim
55 words
A valve as claimed in claim 3 in which said means for varying said spacing comprises an element rotatable about an axis transverse to the axis of said shaft, said element having means therein for locating one end of said stem, and said locating means being spaced from the axis of rotation of said element.
Claim 6
Dependent Claim
27 words
A valve as claimed in claim 1 in which said biasing means comprises a spring engaged between said linkage part and an abutment carried on said housing.
Claim 7
Dependent Claim
21 words
A valve as claimed in claim 5 which includes means for varying the position of said abutment relative to said housing.
Claim 8
Dependent Claim
22 words
A valve as claimed in claim 1 in which said torque motor lies in a passage between said inlet and said outlet.
Claim 9
Dependent Claim
18 words
A valve as claimed in claim 7 which includes a permanent magnet in said passage adjacent said inlet.
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) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |