US3672628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controller for a back seated valve
Assignee: Westinghouse Electric Corp
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Filing: 1970-11-25
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Granted: 1972-06-27
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Expires: 1990-11-25
Abstract
Abstract A hydraulic controller for a back seated steam valve wherein the controller comprises a pair of axially aligned hydraulic cylinders disposed to operate in opposite directions, one of the cylinders having a drive piston and piston rod connected to the valve stem, and the other cylinder having a free piston disposed therein, which opposes the force the drive piston applies to the valve stem as the drive piston approaches the end of its stroke in valve opening direction, thus reducing the back seating force applied to the valve stem by the drive piston. The free piston also increases the initial acceleration of the valves moving parts in closing direction, thus reducing the valve''s closing time.
Inventors
- 👤 Ola J Aanstad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:45
CPC Classifications
F; F16; F16K; F16K31/00; F16K31/12; F16K31/122; F16K31/1225; F01; F01L; F01L1/00; F01L1/12; F01L1/14; F01L1/16; F01L3/00; F01L2003/25; F01L2003/258
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
219 words
A hydraulic controller for a valve having a stem and a back seat on said stem for sealing the stem when the valve is fully opened, the controller comprising a first cylinder having a movable abutment therein, a rod connecting the abutment to the valve stem, a supply of pressurized fluid, a fluid inlet port disposed adjacent one end of the first cylinder, a second cylinder having a bore, one end of which is in communication with the bore of the first cylinder, the bores of the cylinders being generally in axial alignment, the diameter of the bore of the second cylinder being smaller than the diameter of the bore of the first cylinder, a fluid inlet for said second cylinder, the fluid inlets of said cylinders being disposed adjacent the end of said cylinders opposite the ends in communication, a port in communication with said cylinder bores adjacent the area in which said bores are in communication, said port acting as a fluid drain as the abutment moves to open the valve, and means associated with said movable abutment for reducing the force said movable abutment delivers to said rod and said valve stem as said abutment approaches the end of its strokE in valve opening direction, thus reducing the back seating force applied to the valve stem.
Claim 2
Dependent Claim
219 words
A hydraulic controller for a valve having a stem and a back seat on said stem for sealing the stem when the valve is fully opened, the controller comprising a first cylinder having a movable abutment therein, a rod connecting the abutment to the valve stem, a supply of pressurized fluid, a fluid inlet port disposed adjacent one end of the first cylinder, a second cylinder having a bore, one end of which is in communication with the bore of the first cylinder, the bores of the cylinders being generally in axial alignment, the diameter of the bore of the second cylinder being smaller than the diameter of the bore of the first cylinder, a fluid inlet for said second cylinder, the fluid inlets of said cylinders being disposed adjacent the end of said cylinders opposite the ends in communication, a port in communication with said cylinder bores adjacent the area in which said bores are in communication, said port acting as a fluid drain as the abutment moves to open the valve, and means associated with said movable abutment for reducing the force said movable abutment delivers to said rod and said valve stem as said abutment approaches the end of its strokE in valve opening direction, thus reducing the back seating force applied to the valve stem.
Claim 3
Dependent Claim
19 words
A controller as set forth in claim 1 and further comprising means for biasing the valve in closing direction.
Claim 4
Dependent Claim
42 words
A controller as set forth in claim 1 and further comprising a compression spring acting against a disc fastened to the valve stem for closing the valve when pressurized fluid is allowed to flow from the supply inlet of the first cylinder.
Claim 5
Dependent Claim
21 words
A controller as set forth in claim 1, wherein the cylinders are hydraulic cylinders and the pressurized fluid is hydraulic fluid.
Claim 6
Dependent Claim
26 words
A controller as set forth in claim 1, wherein the cylinders are single acting hydraulic cylinders disposed to operate in opposite directions and oppose each other.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |