US3701015A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic pickup with feedback circuit
Assignee: ELECTRO PRODUCTS LAB Inc
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Filing: 1971-01-20
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Granted: 1972-10-24
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Expires: 1991-01-20
Abstract
Abstract A magnetic pickup having an electronic switch circuit for generating a high level digital signal having improved signal form and an improved signal to noise ratio. The switch has an input transistor connected to a sensing coil and an output transistor which generates a digital output signal. The circuit further includes a feedback connection between the output transistor and the input transistor to stabilize operation for low level voltages induced in the pickup coil.
Inventors
- 👤 Kenneth C Dittman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:07
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/4802; G01P3/481; G01P3/488
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
239 words
In a magnetic pickup sensing system having a coil subject to a change in magnetic flux linkage due to relative movement between the coil and a body of magnetic material, a circuit for converting a voltage generated in said coil by said change in flux linkage to a digital signal, comprising: a bistable electronic switch having an input connected with said coil; means for deriving said digital signal as an output from said switch as a function of the voltage generated in the coil; and means defining a feedback path from said output to said input whereby operation of said electronic switch is stabilized for low voltage levels generated in said coil, said switch comprising a first transistor having its base connected to said coil and its emitter-collector circuit connected in series with a first resistance across a source of power, a second transistor having its base connected to the common junction of said first transistor and its associated resistance and its emittercollector circuit connected in series with a second resistance across said source of power; said feedback means comprising resistance means connected to the common junction of said second transistor and its associated resistance and to the base of said first transistor, said resistance means comprising third and fourth resistances connected in series and further including a fifth resistance connected between the common junction of said third and fourth resistances and one side of said source of power.
Claim 2
Dependent Claim
239 words
In a magnetic pickup sensing system having a coil subject to a change in magnetic flux linkage due to relative movement between the coil and a body of magnetic material, a circuit for converting a voltage generated in said coil by said change in flux linkage to a digital signal, comprising: a bistable electronic switch having an input connected with said coil; means for deriving said digital signal as an output from said switch as a function of the voltage generated in the coil; and means defining a feedback path from said output to said input whereby operation of said electronic switch is stabilized for low voltage levels generated in said coil, said switch comprising a first transistor having its base connected to said coil and its emitter-collector circuit connected in series with a first resistance across a source of power, a second transistor having its base connected to the common junction of said first transistor and its associated resistance and its emittercollector circuit connected in series with a second resistance across said source of power; said feedback means comprising resistance means connected to the common junction of said second transistor and its associated resistance and to the base of said first transistor, said resistance means comprising third and fourth resistances connected in series and further including a fifth resistance connected between the common junction of said third and fourth resistances and one side of said source of power.
References Cited (Backward Citations)
US3356082A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |