US3569820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Proximity detection system
Assignee: Bourns Inc
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Filing: 1969-02-24
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Granted: 1971-03-09
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Expires: 1989-02-24
Abstract
Abstract A system to replace directly actuated electric switches in hazardous or other adverse environments, for example aircraft landing-gear-actuated switches, in which system movement of a magnetic target relative to an alternating magnetic field causes a phase shift or inversion in an AC signal which change is detected by a phase detector the output of which controls solidstate electric switches or controllers which may be remote from the adverse environment.
Inventors
- 👤 Robert K Nishimuta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:22
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/94; H03K17/945; H03K17/95; H03K17/9512; B; B64; B64C; B64C25/00; B64C25/02; B64C25/08; B64C25/10; B64C25/18; B64C25/26; B64C25/28; H01; H01F; H01F29/00; H01F29/08; H01F29/10; H03K17/952; H03K17/9525
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
265 words
A proximity detection system for detecting whether a movable member is proximate or remote from a selected location, said system comprising: first means, including AC wave signal-generating means; second means, including a rigid, encased, differential transformer situated at the selected location, said transformer having fixed electrically opposed secondary windings, a stationary, fixed magnetic core and a stationary primary winding connected to said first means to be energized thereby with an applied AC wave signal whereby to enable said transformer to produce an AC output signal, said second means including a movable magnetic member physically separate from said transformer and movable to and from first and second positions respectively proximate to and remote from said location and effective incident to movement from either of said positions to the other to cause inversion of the phase relationship of the output signal thereof to the energizing signal supplied from said first means; third means, including phase-detector means, connected to said first means to receive an AC signal from said generating means and connected to said second means to receive the output signal therefrom, said third means effective to provide a signal of high character incident to reversal of phase relationship from a first phase relationship to a second phase relationship between the output signals from said generating means and said second means, and effective to provide a signal of low character incident to the opposite reversal of such phase relationship; and fourth means, including controlling means connected to said third means, effective to perform a controlling function incident to change of character of signal from said third means.
Claim 2
Dependent Claim
265 words
A proximity detection system for detecting whether a movable member is proximate or remote from a selected location, said system comprising: first means, including AC wave signal-generating means; second means, including a rigid, encased, differential transformer situated at the selected location, said transformer having fixed electrically opposed secondary windings, a stationary, fixed magnetic core and a stationary primary winding connected to said first means to be energized thereby with an applied AC wave signal whereby to enable said transformer to produce an AC output signal, said second means including a movable magnetic member physically separate from said transformer and movable to and from first and second positions respectively proximate to and remote from said location and effective incident to movement from either of said positions to the other to cause inversion of the phase relationship of the output signal thereof to the energizing signal supplied from said first means; third means, including phase-detector means, connected to said first means to receive an AC signal from said generating means and connected to said second means to receive the output signal therefrom, said third means effective to provide a signal of high character incident to reversal of phase relationship from a first phase relationship to a second phase relationship between the output signals from said generating means and said second means, and effective to provide a signal of low character incident to the opposite reversal of such phase relationship; and fourth means, including controlling means connected to said third means, effective to perform a controlling function incident to change of character of signal from said third means.
Claim 3
Dependent Claim
94 words
A proximity-detecting system as defined in claim 1, in which said differential transformer is provided with an exposed face exposing a portion of said core having a nonmagnetic gap in the flux path thereof, and in which said movable member is movable relative to said gap to and from positions respectively proximate to and remote from said core to decrease and increase said gap, respectively, to thereby invert the phase of the secondary winding output potential relative to the phase of the AC wave signal applied from the signAl-generating means to said primary winding.
Claim 4
Dependent Claim
69 words
A proximity-detecting system according to claim 1, in which said phase-detector means comprise a transistor and first and second amplifier means the outputs of which are connected to bias said transistor to conduct to produce a detector output signal incident to the respective AC signals applied thereto from said generating means and said first means having a selected relative phase relationship selected from among phase opposition and phase coincidence.
Claim 5
Dependent Claim
165 words
A proximity-detecting system according to claim 1, in which said differential transformer is provided with an exposed face and in which said core is provided with a nonmagnetic flux-path gap at said face, and in which said movable member is movable adjacent said face to and from positions respectively proximate to and remote from said gap to thereby cause reversal of the phase relationship of the secondary winding AC output signal relative to the AC wave signal applied from the said signal-generating means to the said primary winding, and in which system said phase-detector means comprise a transistor and first and second amplifier means the outputs of which are connected to bias said transistor to conduct to produce a detector output signal incident to the respective AC signals applied thereto from said generating means and from said first means having a selected phase relationship selected from among phase opposition and phase coincidence, said transistor being connected to said fourth means to provide a signal thereto.
Claim 6
Dependent Claim
94 words
A proximity-detecting system according to claim 4, in which said first amplifier means comprises wave-squaring means and an output line, said phase-detector means further comprising a diode in the said output line effective to pass only alternate half-cycles of the output of said squaring means, and in which system said second amplifier means comprises a differential amplifier, and in which system the passed half-cycles of the signal from said squaring means are effective to bias said transistor off incident to the output signals of said first and second amplifier means being in phase coincidence.
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) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |