US4584902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Valve actuators
Assignee: Rotork Controls Ltd
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Filing: 1983-06-01
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Granted: 1986-04-29
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Expires: 2003-06-01
Abstract
Abstract A valve actuator is disclosed which comprises only two housings, namely a first housing defining a single enclosure for a reversible electric motor, electrical control gear associated with the motor and torque control means and travel limit switch mechanism, and a second housing comprising a gear box containing reduction gearing.
Inventors
- 👤 Jeremy J. Fry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:30
CPC Classifications
H; H02; H02K; H02K7/00; H02K7/10; H02K7/116; H02K7/1163; H02K7/1166; H02K11/00; H02K11/20; H02K11/21; H02K11/24; H02K11/30; H02K11/33; H02K11/38; H02K5/00; H02K5/04; H02K5/12; H02K5/136; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2186
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
91 words
A valve actuator comprising only two housings, namely (a) a first housing defining a single enclosure for (1) a reversible electric motor, (2) electrical control gear associated with the motor and (3) torque control means and travel limit switch mechanism and (b) a second housing comprising a gear box containing reduction gearing, a main drive extending from the electric motor to the reduction gearing and wherein the first housing has an outlet opening sealingly closed by a terminal block through which pass manual adjustment members for the travel limit switch mechanism.
Claim 2
Dependent Claim
91 words
A valve actuator comprising only two housings, namely (a) a first housing defining a single enclosure for (1) a reversible electric motor, (2) electrical control gear associated with the motor and (3) torque control means and travel limit switch mechanism and (b) a second housing comprising a gear box containing reduction gearing, a main drive extending from the electric motor to the reduction gearing and wherein the first housing has an outlet opening sealingly closed by a terminal block through which pass manual adjustment members for the travel limit switch mechanism.
Claim 3
Dependent Claim
17 words
A valve actuator according to claim 1, wherein all manual adjustment members pass through said terminal block
Claim 4
Dependent Claim
25 words
A valve actuator according to claim 1 wherein additional sealing is provided at said outlet opening by a potting compound disposed behind the terminal block.
Claim 5
Dependent Claim
38 words
A valve actuator according to claim 1, wherein the terminal block is provided with a cover sealed to said outlet opening to enclose ends of said adjustment members and terminals on the outer side of the terminal block.
Claim 6
Dependent Claim
18 words
A valve actuator according to claim 4, wherein said cover has a removable lid sealingly secured to it.
Claim 7
Dependent Claim
29 words
A valve actuator according to claim 1 wherein the travel limit switch mechanism is driven from the main drive through a second reduction gearing contained within said first housing.
Claim 8
Dependent Claim
65 words
A valve actuator according to claim 6, wherein said main drive includes a worm shaft extending from a connection with the electric motor shaft into the gear box where it carries a worm meshing with a worm wheel to form the first mentioned reduction gearing and wherein the worm shaft carries a further worm meshing with a worm wheel to form said second reduction gearing.
Claim 9
Dependent Claim
38 words
A valve actuator according to claim 1, wherein the gear box houses a drive column and wherein one end of said drive column is closed by a cover which is secured to the gear box by tie bolts.
Claim 10
Dependent Claim
39 words
A valve actuator according to claim 8, wherein the gear box has a separately formed drive connector block mounted on the gear box by tie bolts at least some of which are used in common to secure said cover.
Claim 11
Dependent Claim
53 words
A valve actuator according to claim 9, wherein said gear box is provided at the end of the column opposite the cover with recesses for the heads of tie bolts so that the cover can be secured in position by the tie bolts when a separately formed drive connector block is not provided.
Claim 12
Dependent Claim
27 words
A valve actuator according to claim 8, wherein the cover has a knock-out top and an internal thread into which an extension cover tube can be screwed.
References Cited (Backward Citations)
GB1450447A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-28 | 1989-10-28 | 1990-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-28 | 1993-10-28 | 1994-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-28 | 1997-10-28 | 1998-04-29 | $7700.00 | Window Closed / Lapsed |