US3791231A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Turbine turning mechanism
Assignee: Elliott Turbomachinery Co Inc
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Filing: 1972-04-03
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Granted: 1974-02-12
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Expires: 1992-04-03
Abstract
Abstract A fluid operated piston and cylinder structure is employed to impart intermittent rotation to a steam turbine subsequent to shutdown. Preferably the motion transmitting means between the piston and cylinder structure and the turbine shaft consists of a ratchet wheel fixed to the shaft and a pawl operated by the piston and cylinder. Means is provided to restrain movement of the pawl into engagement with the ratchet when the turbine is operating. Preferably the pawl restraining means is operated automatically upon the turbine reaching a predetermined speed.
Inventors
- 👤 C Geary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:16
CPC Classifications
F; F01; F01D; F01D25/00; F01D25/34; Y; Y10; Y10T; Y10T74/00; Y10T74/15; Y10T74/1526; Y10T74/1553; Y10T74/1555
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
187 words
A turning mechanism for intermittently rotating steam turbines subsequent to shutdown comprising a tooth ratchet wheel fixedly secured to the turbine shaft for rotation therewith, an arm extending radially of said ratchet wheel and having an end portion extending outwardly from the periphery of said ratchet wheel, a pawl pivotally mounted on the extending portion of said arm for movement into and out of engagement with the teeth on said ratchet wheel, a powered driver connected to said arm and being operable to effect oscillation thereof about said axis, said pawl being operable upon engagement with said ratchet wheel during oscillation of said arm in one direction to effect rotation of said ratchet wheel and the turbine shaft, a wall encircling said ratchet wheel and said arm, means for restraining movement of said pawl into engagement with the teeth of said ratchet wheel and including an arcuate shoe member carried by said wall and movable into and out of engagement with said pawl, said shoe member being operable upon such engagement to maintain said pawl out of engagement with said ratchet wheel during oscillation of said arm.
Claim 2
Dependent Claim
187 words
A turning mechanism for intermittently rotating steam turbines subsequent to shutdown comprising a tooth ratchet wheel fixedly secured to the turbine shaft for rotation therewith, an arm extending radially of said ratchet wheel and having an end portion extending outwardly from the periphery of said ratchet wheel, a pawl pivotally mounted on the extending portion of said arm for movement into and out of engagement with the teeth on said ratchet wheel, a powered driver connected to said arm and being operable to effect oscillation thereof about said axis, said pawl being operable upon engagement with said ratchet wheel during oscillation of said arm in one direction to effect rotation of said ratchet wheel and the turbine shaft, a wall encircling said ratchet wheel and said arm, means for restraining movement of said pawl into engagement with the teeth of said ratchet wheel and including an arcuate shoe member carried by said wall and movable into and out of engagement with said pawl, said shoe member being operable upon such engagement to maintain said pawl out of engagement with said ratchet wheel during oscillation of said arm.
Claim 3
Dependent Claim
82 words
A turning mechanism according to claim 1 wherein said pawl restraining means includes a permanent magnet fixed to said arm in juxtaposition to said pawl, and means carried by said ratchet wheel and operable upon said turbine shaft and ratchet wheel reaching a predetermined speed of rotation to Move said pawl into the effective field of said magnet, said magnet being operable upon said pawl being moved into said effective field to maintain said pawl out of engagement with said ratchet wheel.
Claim 4
Dependent Claim
32 words
A turning mechanism according to claim 2 and including reset means mounted in said wall and operable exteriorly thereof to move said pawl out of the effective field of said permanent magnet.
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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |