Patent US3827291A successfully refreshed from Google Patents.
US3827291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transducer systems for detection of relative displacement
Assignee: Rolls Royce Power Engineering PLC
•
Filing: 1971-11-29
•
Granted: 1974-08-06
•
Expires: 1991-11-29
Abstract
Abstract A transducer system wherein relative displacement of two members is detected by the change in inductive coupling between a single coil on one member and a pair of opposed coils on the other member, an A.C. input being applied to the coil or coils on one of the members and the output from the coils or coil on the other member being detected when the single coil is displaced from its normal symmetrical position relative to the two coils. The displacement to be measured may result from mechanical movement or vibration or from load, pressure or acceleration applied to devices incorporating the transducer system.
Inventors
- 👤 Calvey L Mc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:45
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/16; G01B7/24; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/20; G01D5/204; G01D5/2073; H; H01; H01F; H01F29/00; H01F29/08; H01F29/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
244 words
A transducer system for detection and/or measurement of relative displacement comprising two relatively-displaceable members, first electrical coil means mounted on one of said members and second electrical coil means mounted on the other of said members, said first electrical coil means comprising a single coil and said second electrical coil means comprising a pair of series-connected coils arranged to interact inductively with the single coil of the first coil means in opposition to one another whereby the inductive interactions are balanced against one another when the single coil is in a symmetrical position relative to the coils of the pair, means for supplying an alternating current to one of said coil means, and means for detecting the currents induced in the other of said coil means, wherein the coils of the first and second coil means are in the form of rectangular spirals having parallel axes, said axes being perpendicular to the direction of relative displacement of the members, the coils of the second coil means lie in a common plane with their centres spaced apart in the direction of relative displacement of said members, the coil of the first coil means lies in a plane parallel to said common plane, each of the coils has the same number of turns, and the length of side of each turn of the single coil of the first coil means is greater than that of the corresponding turn of each coil of the second coil means.
Claim 2
Dependent Claim
244 words
A transducer system for detection and/or measurement of relative displacement comprising two relatively-displaceable members, first electrical coil means mounted on one of said members and second electrical coil means mounted on the other of said members, said first electrical coil means comprising a single coil and said second electrical coil means comprising a pair of series-connected coils arranged to interact inductively with the single coil of the first coil means in opposition to one another whereby the inductive interactions are balanced against one another when the single coil is in a symmetrical position relative to the coils of the pair, means for supplying an alternating current to one of said coil means, and means for detecting the currents induced in the other of said coil means, wherein the coils of the first and second coil means are in the form of rectangular spirals having parallel axes, said axes being perpendicular to the direction of relative displacement of the members, the coils of the second coil means lie in a common plane with their centres spaced apart in the direction of relative displacement of said members, the coil of the first coil means lies in a plane parallel to said common plane, each of the coils has the same number of turns, and the length of side of each turn of the single coil of the first coil means is greater than that of the corresponding turn of each coil of the second coil means.
Claim 3
Dependent Claim
68 words
A transducer system as claimed in claim 1 constructed as a strain gauge, a first of said members being attached to a part subject to stress at a single location whereby it is not displaced when the stress alters while the second of the said members is attached to the said part at a different location whereby it is displaced relative to the first upon change in stress.
Claim 4
Dependent Claim
77 words
A transducer system as claimed in claim 1 wherein a first of said members is a part which is subject to stress and the second of said members is secured to said first member at a first location and extends parallel to said first member in cantilevered manner to support one of said first and second electrical coil means at a second location, whereby said relative displacement occurs upon change of stress applied to said first member.
References Cited (Backward Citations)
US2276816A
Cited
US2422806A
Cited
US2452862A
Cited
US2836803A
Cited
US2905914A
Cited
US3202948A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |