Patent US3861818A successfully refreshed from Google Patents.
US3861818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thrust wear detector
Assignee: General Electric Co
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Filing: 1974-02-14
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Granted: 1975-01-21
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Expires: 1994-02-14
Abstract
Abstract An improved thrust wear detector for a turbomachine includes a hydraulically positioned follower piston which is testable against sticking to the detector casing. A calibrated orifice used to blanace the follower piston is accessible for maintenance without disassembly of the wear detector. Movement of the follower piston, indicating bearing wear, is measured directly from the piston and false tripouts due to pressure switch failure is averted by providing redundant pressure switches.
Inventors
- 👤 Markus A Eggenberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:11
CPC Classifications
F; F01; F01D; F01D21/00; F01D21/04; G; G01; G01B; G01B21/00; G01B21/16
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
125 words
A device for following the axial movement of a rotating shaft including a casing mounted adjacent the rotating shaft having a hydraulically positioned follower piston slidably mounted within the casing defining opposite first and second chambers; the device further comprising: a piston nozzle slidably mounted within the follower piston, the piston nozzle having an open end closely adjacent the rotating shaft defining a hydraulic gap therebetween; the first chamber in fluid communication with the second chamber and the second chamber in fluid communication with the piston nozzle and hydraulic gap; a collar formed on the piston nozzle defining an internal chamber within the follower piston; means for selectively introducing hydraulic fluid into the internal chamber; and, means biasing the piston nozzle against the follower piston.
Claim 2
Independent Claim
125 words
A device for following the axial movement of a rotating shaft including a casing mounted adjacent the rotating shaft having a hydraulically positioned follower piston slidably mounted within the casing defining opposite first and second chambers; the device further comprising: a piston nozzle slidably mounted within the follower piston, the piston nozzle having an open end closely adjacent the rotating shaft defining a hydraulic gap therebetween; the first chamber in fluid communication with the second chamber and the second chamber in fluid communication with the piston nozzle and hydraulic gap; a collar formed on the piston nozzle defining an internal chamber within the follower piston; means for selectively introducing hydraulic fluid into the internal chamber; and, means biasing the piston nozzle against the follower piston.
Claim 3
Dependent Claim
18 words
The device recited in claim 1 further comprising a calibrated orifice interconnecting the first and second opposite chambers.
Claim 4
Dependent Claim
14 words
The device recited in claim 2 wherein the calibrated orifice is outside the casing.
Claim 5
Dependent Claim
63 words
The device recited in claim 3 further including: a first fluid supply connected to the first chamber; a second fluid supply connected to the second chamber including a valve for selectively introducing the second fluid supply into the second chamber; and, a pipe interconnecting the first and second fluid supplies at a point downstream from the valve, the pipe including the calibrated orifice.
Claim 6
Dependent Claim
27 words
The device recited in claim 4 further including: a third fluid supply connected to the internal chamber; and, means for selectively introducing fluid into the internal chamber.
Claim 7
Dependent Claim
58 words
The device recited in claim 1 further comprising: a pilot valve positioned by the follower piston and hydraulically connected to first and second pairs of pressure switches; and, an electrical alarm and shutdown circuit connected to two pairs of pressure switches, whereby loss of hydraulic pressure in either pair of pressure switches causes activation of the electric circuit.
Claim 8
Dependent Claim
23 words
The device recited in claim 1 further including a linear variable differential transformer having a rod slidable therein positioned by the follower piston.
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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |