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US3893025A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for determining the distance to a concealed conductive structure

Assignee: Individual
•
Filing: 1974-02-01
•
Granted: 1975-07-01
•
Expires: 1994-02-01
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Abstract

Abstract A device for locating concealed conductive structures in both horizontal and vertical planes wherein depth measurements are accomplished by a comparison of the signal outputs from two vertically spaced antennas which are energized by a signal radiated from a buried or otherwise concealed object.

Inventors

  • 👤 Jr Thomas G Humphreys

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 16:11
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/08

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 187 words
A locator for determining the distance to a concealed conductive object lying along a known direction and wherein the object is radiating an alternating current signal, said locator comprising: first and second signal receptors, each being adapted to receive said signal and provide an output voltage in proportion to the level of said signal as received; support means for positioning said receptors a selected and fixed distance apart whereby one receptor may be positioned a selected distance greater than the other from said object; signal combining means, including adjustment means, coupled to the outputs of said receptors for adjustably combining said outputs in a subtractive mode and providing a combined signal output which is reducible to a substantially zero level as a function of setting of said adjustment means; detection means responsive to the output of said signal combining means for indicating when said combined signal output is at a substantially zero level; and depth indication means coupled to said signal combining means and responsive to adjustment of said adjustment means and the distance apart of said receptor for indicating the distance to a concealed conductive object.
Claim 2
Dependent Claim 187 words
A locator for determining the distance to a concealed conductive object lying along a known direction and wherein the object is radiating an alternating current signal, said locator comprising: first and second signal receptors, each being adapted to receive said signal and provide an output voltage in proportion to the level of said signal as received; support means for positioning said receptors a selected and fixed distance apart whereby one receptor may be positioned a selected distance greater than the other from said object; signal combining means, including adjustment means, coupled to the outputs of said receptors for adjustably combining said outputs in a subtractive mode and providing a combined signal output which is reducible to a substantially zero level as a function of setting of said adjustment means; detection means responsive to the output of said signal combining means for indicating when said combined signal output is at a substantially zero level; and depth indication means coupled to said signal combining means and responsive to adjustment of said adjustment means and the distance apart of said receptor for indicating the distance to a concealed conductive object.
Claim 3
Dependent Claim 16 words
A locator as set forth in claim 1 wherein said signal combining means comprises a potentiometer.
Claim 4
Dependent Claim 23 words
A locator as set forth in claim 1 further comprising an amplifier coupling the output of each receptor to said signal combining means.
Claim 5
Dependent Claim 45 words
A locator as set forth in claim 2 wherein the output of one of said receptors is connected across the full range of said potentiometer and the output of the other said receptor is connected across an adjustable portion of the range of said potentiometer.
Claim 6
Dependent Claim 51 words
A locator as set forth in claim 2 wherein the outputs of said receptors are connected in series across the full impedence Of said potentiometer and the output of said signal combining means is coupled from the adjustable arm of said potentiometer and a common receptor connection to said detection means.
Claim 7
Dependent Claim 39 words
A locator as set forth in claim 2 wherein said potentiometer is adjustable to provide a resistance which varies as the square of the distance of adjustment of said potentiometer, whereby said depth indication means comprises a linear scale.
Claim 8
Dependent Claim 28 words
A locator as set forth in claim 2 wherein said detection means comprises means for providing a variable frequency output as a function of the detected signal level.
Claim 9
Dependent Claim 30 words
A locator as set forth in claim 2 wherein said detection means includes means for providing an audible signal output indicative of the output of said signal level adjustment means.
Claim 10
Dependent Claim 48 words
A locator as set forth in claim 1 further comprising selection means coupled to at least one of said signal receptors for coupling it directly to said detection means whereby in this mode of connection said locator is adapted to determine the direction along which said object extends.
Claim 11
Dependent Claim 29 words
A locator as set forth in claim 2 wherein each said signal receptor comprises an electrical capacitor connected in parallel whereby said receptor is tuned to a preselected frequency.

References Cited (Backward Citations)

US1897688A Cited
US2358027A Cited
US2471105A Cited
US2428326A Cited
US3562633A Cited
US3617865A Cited
US3704413A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-06-30 1978-12-30 1979-07-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-30 1982-12-30 1983-07-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-30 1986-12-30 1987-07-01 $7700.00 Window Closed / Lapsed

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