Patent US1654497A successfully refreshed from Google Patents.
Patent US3701015A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3701015A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic pickup with feedback circuit

Assignee: ELECTRO PRODUCTS LAB Inc
•
Filing: 1971-01-20
•
Granted: 1972-10-24
•
Expires: 1991-01-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

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 22:44
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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag