Two mode boring tool guiding system and method

• US 6,057,687 A
• Filed: 04/13/1998
• Issued: 05/02/2000
• Est. Priority Date: 03/01/1991
• Status: Expired due to Fees

• Current Assignee: Merlin Technologies Incorporated
• Original Assignee: Digital Control Incorporated
• Inventors: Mercer, John E.
• Primary Examiner(s): Snow, Walter E.
• Application Number:
  US09/058,981
• Time in Patent Office: 750 Days
• Field of Search: 324/326, 324/327, 324/328, 324/329, 324/226, 324/247, 175/40, 175/45
• US Class Current: 324/326
• CPC Class Codes: E21B 47/0228 using electromagnetic energy or detectors therefor
• CPC Class Codes: E21B 47/0232 at least one of the energy sources or one of the detectors being located on or above the ground surface
• CPC Class Codes: E21B 47/024 of devices in the borehole determining slope or direction of the borehole E21B47/022
• CPC Class Codes: G01C 9/06 Electric or photoelectric indication or reading means
• CPC Class Codes: G01C 9/20 the indication being based on the inclination of the surface of a liquid relative to its container
• CPC Class Codes: G01V 3/165 operating with magnetic or electric fields produced or modified by the object or by the detecting device with electromagnetic waves G01V3/17

Abstract

A boring tool contains an arrangement for producing a dipole magnetic field. The boring tool is steered through the ground using a boring machine. The position of the boring tool, during its movement through the ground, is established by an above ground receiver in cooperation with and responsive to the magnetic field. The receiver is configured to operate alternatively in first and second modes. When operating the receiver in the first mode positioned above ground, the receiver includes an arrangement responsive to the magnetic field for determining the location of the boring tool as the boring tool moves along a path from a first point to a second point. When operating the receiver in the second mode positioned at a fixed point, the receiver includes an arrangement responsive to the magnetic field for establishing between the boring tool and the receiver a homing path along which the boring tool is steered toward the fixed point.

Claims

1. In a system in which a boring tool containing means for producing a dipole magnetic field is steered through the ground by means of a boring machine and in which the position of the boring tool during its movement through the ground is established by means of an above-ground receiver in cooperation with and responsive to said magnetic field, the improvement comprising:

(a) said receiver which is configured to operate alternatively in first and second modes such that

(i) the receiver, operating in said first mode positioned above ground, includes means responsive to said magnetic field for determining the particular location of the boring tool as the boring tool moves along said path from a first point to a second point, and

(ii) the receiver, operating in said second mode positioned at a fixed point, includes means responsive to said magnetic field for establishing between said boring tool and said receiver a homing path along which said boring tool is steered toward said fixed point.

2. The Improvement according to claim 1 wherein said receiver includes first and second orthogonal antennae.

3. The improvement according to claim 2 wherein said antennae are oriented at angles of 45°

with the horizontal when the receiver is operating in its first mode positioned above ground and remote from said particular path.

4. The improvement according to claim 2 wherein the antennae are oriented in substantially a horizontal plane when the receiver is operating in its second mode positioned at said fixed point.

8. The improvement according to claim 2 wherein the antennae are oriented in substantially a vertical plane when the receiver is operating in its second mode positioned at said fixed point.

9. The improvement according to claim 4 wherein said receiver includes third and fourth orthogonal antennae oriented in substantially a vertical plane when the receiver is operating in its second mode positioned at said fixed point.

10. The improvement according to claim 1 wherein said receiver includes a first pair of first and second orthogonal antennae and a second pair of third and fourth orthogonal antennae.

5. In a method of guiding a boring tool containing means for producing a dipole magnetic field through the ground by means of a boring machine and in which the position of the boring tool during its movement through the ground is established by means of an above-ground receiver in cooperation with and responsive to said magnetic field, the improvement comprising:

(a) providing a receiver which is configured to operate alternatively in first and second modes such that

(i) the receiver, operating in said first mode positioned above the ground, includes means responsive to said magnetic field for determining the particular location of the boring tool as the boring tool moves along said path from a first point to a second point, and

(ii) the receiver, operating in said second mode positioned at a fixed point, includes means responsive to said magnetic field for establishing between said boring tool and said receiver a homing path along which said boring tool is steered toward said fixed point; and

(b) guiding said boring tool through the ground by operating said receiver in said first mode.

6. In a method of guiding a boring tool containing means for producing a dipole magnetic field through the ground by means of a boring machine and in which the position of the boring tool during its movement through the ground is established by means of an above-ground receiver in cooperation with and responsive to said magnetic field, the improvement comprising:

(a) providing a receiver which is configured to operate alternatively in first and second modes such that

(i) the receiver, operating in said first mode positioned above the ground, includes means responsive to said magnetic field for determining the particular location of the boring tool as it moves along said path from a first point to a second point, and

(ii) the receiver, operating in said second mode positioned at a fixed point, includes means responsive to said magnetic field for establishing between said boring tool and said receiver a homing path along which said boring tool is steered toward said fixed point; and

(b) guiding said boring tool through the ground by operating said receiver in said second mode.

7. The improvement according to claim 6 including the step of guiding said boring tool through the ground by operating the receiver in said first mode.