Electrical conductor locating device

• US 7,145,319 B2
• Filed: 05/18/2005
• Issued: 12/05/2006
• Est. Priority Date: 05/26/2004
• Status: Active Grant

• Current Assignee: William Herbert Dunning
• Original Assignee: William Herbert Dunning
• Inventors: Dunning, William Herbert
• Primary Examiner(s): Deb, Anjan
• Assistant Examiner(s): Dole, Timothy J.
• Application Number:
  US11/131,754
• Publication Number:
  US 20050264274A1
• Time in Patent Office: 566 Days
• Field of Search: 324/66, 324/67
• US Class Current: 324/66
• CPC Class Codes: G01V 3/104 using several coupled or uncoupled coils G01V3/101 takes precedence

Abstract

An electrical conductor locating device comprises a pulse generator and a detector. The pulse generator includes a transformer with outputs for connecting to two positions along the electrical conductor to define a closed loop. The current in the closed loop produces an electromagnetic field around the conductor. The detector is comprised of a magnetic field sensor coupled to the input of an amplifier. The output of the amplifier is connected to an indicator, such as a LED. When the sensor is moved perpendicularly closer to the conductor, it senses an increasing magnetic or electromagnetic field strength so the amplifier drives the indicator at greater intensity. When the sensor is directly aligned with the conductor, the sensor is inside the equipotential point of the magnetic or electromagnetic field where the field strength approaches zero, so the amplifier drives the indicator at close to zero intensity and thus pinpoints the conductor.

Claims

1. An electrical conductor locating device, comprising:

an amplifier;

a magnetic field sensor including at least a coiled wire connected to an input of the amplifier;

an indicator connected to an output of the amplifier, wherein the amplifier is arranged to activate the indicator when the sensor is moved into proximity of the conductor, and to deactivate the indicator when the sensor is moved to a generally equipotential point of the electromagnetic field around the conductor; and

a laser aligned with a through-hole in the sensor for directing a laser beam through the through-hole.

2. The electrical conductor locating device of claim 1, wherein the amplifier comprises an op-amp.

3. The electrical conductor locating device of claim 1, wherein the indicator comprises a lamp.

4. The electrical conductor locating device of claim 1, further including a filter connected between the sensor and the input of the amplifier.

5. The electrical conductor locating device of claim 1, further including additional magnetic field sensors in a 3-axis arrangement for pinpointing the conductor in three dimensions.

6. An electrical conductor locating device, comprising:

an electrical pulse generator for connecting to an electrical conductor, wherein the generator is arranged for delivering pulses to the conductor and producing an electromagnetic field around the conductor; and

a detector including at least

a magnetic field sensor connected to an input of an amplifier,

an indicator connected to an output of the amplifier, wherein the amplifier is arranged to activate the indicator when the sensor is moved into proximity of the conductor, to deactivate the indicator when the sensor is moved to a generally equipotential point of the electromagnetic field around the conductor, and

a laser aligned with a through-hole in the sensor for directing a laser beam through the through-hole.

7. The electrical conductor locating device of claim 6, wherein the pulse generator includes a transformer with outputs for connecting to the conductor to define a closed loop.

8. The electrical conductor locating device of claim 6, wherein the amplifier comprises an op-amp.

9. The electrical conductor locating device of claim 6, wherein the indicator comprises a lamp.

10. The electrical conductor locating device of claim 6, further including a filter connected between the sensor and the input of the amplifier.

11. The electrical conductor locating device of claim 6, further including additional magnetic field sensors in a 3-axis arrangement for pinpointing the conductor in three dimensions.

12. An electrical conductor locating device, comprising:

an electrical pulse generator with a transformer with outputs for connecting to an electrical conductor to define a closed loop, wherein the generator is arranged for delivering pulses to the conductor and producing an electromagnetic field around the conductor; and

a detector including at least

a coiled wire connected through a filter to an input of an amplifier,

an indicator connected to an output of the amplifier, wherein the amplifier is arranged to activate the indicator when the coiled wire is moved into proximity of the conductor, and to deactivate the indicator when the coiled wire is moved to a generally equipotential point of the electromagnetic field around the conductor, and

a laser aligned with a through-hole in the sensor for directing a laser beam through the through-hole.

13. The electrical conductor locating device of claim 12, further including additional magnetic field sensors in a 3-axis arrangement for pinpointing the conductor in three dimensions.

14. A system comprising:

a sensor for sensing an electromagnetic field, wherein the sensor has a through-hole;

an indicator for indicating that the sensor senses the electromagnetic field, wherein the indicator is deactivated when an equipotential point of the electromagnetic field is found;

a beam source aligned with the through-hole in the sensor for shining a beam through the through-hole, wherein the sensor and the beam source are configured such that when the equipotential point of the electromagnetic field is reached, a direction associated with the beam is indicative of information associated with a location of a source of the electromagnetic field.

15. A method comprising:

sensing an electromagnetic field, via a sensor that has a though-hole;

in response to the sensing, sending a signal to an indicator that activates the indicator;

deactivating the indicator in response to moving the sensor into an equipotential in the electromagnetic field; and

shining a beam through the through-hole within the sensor, wherein when the equipotential point in the electromagnetic field is reached by the sensor, a direction associated with the beam is indicative of information associated with a location of a source of the electromagnetic field.