US3738175A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for detecting the thermal overloads of a rotating member
Assignee: U N E L E C
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Filing: 1971-10-04
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Granted: 1973-06-12
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Expires: 1991-10-04
Abstract
Abstract A device for detecting thermal overload in a rotating member includes a piece made from magnetic material having a Curie point corresponding to the temperature to be detected disposed on said rotating member so as to rotate along a path adjacent a stationary magnetic bridge consisting of two arms through which pass opposite fluxes of equal magnitude separated by an air gap in which a magnetic detector is located so that an increase in temperature of the rotating member beyond the Curie point of the magnetic piece can be detected by the magnetic detector as a reduction in signal level or a complete loss of signal.
Inventors
- 👤 A Linsig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:05
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/36; G01K7/38
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
107 words
An arrangement for detecting thermal overloads in a rotating member, comprising a magnetic piece carried by the rotating member and a stationary magnetic bridge including two arms which normally carry opposite magnetic fluxes of equal magnitude separated by an air gap in which a magnetic field detector is located, said magnetic bridge having its axis passing through said air gap which is disposed adjacent the path of said magnetic piece in the course of the rotation thereof, said magnetic piece being made from a magnetic material whose permeability varies in accordance with the temperature thereof and whose Curie point corresponds to a critical temperature to be detected.
Claim 2
Dependent Claim
107 words
An arrangement for detecting thermal overloads in a rotating member, comprising a magnetic piece carried by the rotating member and a stationary magnetic bridge including two arms which normally carry opposite magnetic fluxes of equal magnitude separated by an air gap in which a magnetic field detector is located, said magnetic bridge having its axis passing through said air gap which is disposed adjacent the path of said magnetic piece in the course of the rotation thereof, said magnetic piece being made from a magnetic material whose permeability varies in accordance with the temperature thereof and whose Curie point corresponds to a critical temperature to be detected.
Claim 3
Dependent Claim
36 words
An arrangement for detecting thermal overloads according to claim 1 wherein said magnetic piece is secured to the periphery of the rotor of a rotary machine, outside of the magnetic circuit thereof, on a current conductor.
Claim 4
Dependent Claim
19 words
An arrangement for detecting thermal overloads according to claim 1 wherein said magnetic field detector is a Hall-effect device.
Claim 5
Dependent Claim
68 words
An arrangement for detecting thermal overloads according to claim 1 wherein said magnetic bridge comprises first and second permanent magnets, a first pole piece interconnecting one corresponding pole of said first and second permanent magnets, and second and third pole pieces respectively contacting the other corresponding poles of said first and second permanent magnets so as to form a gap therebetween, said detector being disposed in said gap.
Claim 6
Dependent Claim
19 words
An arrangement for detecting thermal overloads according to claim 4 wherein said magnetic field detector is a Hall-effect device.
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) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |