Multisegmented toroidal magnetic field projector

Patent metadata

Field	Value
Publication number	US-9500446-B2
Application number	US-201414515289-A
Country	US
Kind code	B2
Filing date	Oct 15, 2014
Priority date	Oct 15, 2014
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A system for triggering improvised explosive devices (IEDs) with an alternating magnetic field. In one embodiment, the magnetic field is produced by a magnetic field projector in the shape of one-half of a torus, the half-torus being composed of several conductive segments referred to as toroidal wedges. A poloidal current flows in each toroidal wedge, producing a magnetic field that is projected by the half-torus. The magnetic field may induce a current, producing heating, in a conductive loop in an IED and triggering the IED.

First claim

What is claimed is:

1. A system for projecting an oscillatory magnetic field, the system comprising:
a plurality of conductive toroidal wedges;
each toroidal wedge being a section of tube having two substantially planar ends, at least one of the substantially planar ends having a normal oblique to the centerline of the tube,
the section of tube having a slit extending between the two substantially planar ends, and

a plurality of non-conductive spacers;
the toroidal wedges being assembled to form an assembly substantially in the shape of a portion of a torus.

2. The system of claim 1 , wherein the section of tube forming a toroidal wedge of the plurality of toroidal wedges has a cross section that is substantially circular.

3. The system of claim 1 , wherein the section of tube forming a toroidal wedge of the plurality of toroidal wedges has a cross section that is substantially rectangular.

4. The system of claim 1 , wherein the slit in the section of tube forming a toroidal wedge of the plurality of toroidal wedges is substantially parallel to the centerline of the section of tube.

5. The system of claim 4 , wherein the slit in the section of tube forming a toroidal wedge of the plurality of toroidal wedges is substantially in a plane parallel to the normals of the substantially planar ends of the section of tube.

6. The system of claim 1 , wherein the angle between the normals of the substantially planar ends of the section of tube forming a toroidal wedge of the plurality of toroidal wedges is less than 45 degrees.

7. The system of claim 1 , wherein the angle between the normals of the substantially planar ends of the section of tube forming a toroidal wedge of the plurality of toroidal wedges is greater than 10 degrees.

8. The system of claim 1 , wherein the minor diameter of the portion of the torus is greater than 4 inches and less than 8 inches.

9. The system of claim 1 , wherein the major diameter of the portion of the torus is greater than 12 inches and less than 24 inches.

10. The system of claim 1 , wherein the tube diameter of the portion of the torus is greater than 4 inches and less than 8 inches.

11. The system of claim 1 , wherein the centerline length of the section of tube forming a toroidal wedge of the plurality of toroidal wedges is less than the tube diameter of the portion of the torus.

12. The system of claim 1 , wherein the section of tube forming a toroidal wedge of the plurality of toroidal wedges comprises a layer of steel and a layer of copper.

13. The system of claim 12 , wherein the thickness of the layer of copper is less than 10% of the thickness of the layer of steel.

14. The system of claim 1 , wherein the non-conductive spacers are composed primarily of fiberglass reinforced plastic.

15. The system of claim 1 , comprising an upper non-conductive support plate and a lower non-conductive support plate, configured to sandwich the assembly.

16. The system of claim 15 , further comprising a plurality of pins,
wherein:
the toroidal wedges of the plurality of toroidal wedges comprise a plurality of holes;
the non-conductive spacers of the plurality of non-conductive spacers comprise a plurality of holes; and
the upper non-conductive support plate and the lower non-conductive support plate comprise a plurality of holes located so as to be aligned with the holes in the toroidal wedges and the holes in the non-conductive spacers, and

each of the plurality of pins is positioned in a hole in the upper non-conductive support plate or in the lower non-conductive support plate, and in a hole in a toroidal wedge or in a non-conductive spacer.

17. The system of claim 1 , further comprising a plurality of conductive bridges, a conductive bridge of the plurality of conductive bridges connected to a first toroidal wedge and to a second toroidal wedge, the first toroidal wedge, the conductive bridge, and the second toroidal wedge being thereby connected in series.

18. The system of claim 1 , further comprising a class E amplifier configured to drive a current through a toroidal wedge.

19. The system of claim 1 , configured to project an oscillatory magnetic field oscillating at a frequency in the range from 1 megahertz to 30 megahertz.

Assignees

• Raytheon Co

Inventors

• Crouch David D
• Kato Keith G

Classifications

• F42D5/04

  Rendering explosive charges harmless, e.g. destroying ammunition ({F42B39/14 and F42B39/20 take precedence } ; extracting primers, dismantling ammunition F42B33/04, F42B33/06 {; chemical deactivating of explosives C06B21/0091}); Rendering detonation of explosive charges harmless · CPC title

• H01Q21/26

  Turnstile or like antennas comprising arrangements of three or more elongated elements disposed radially and symmetrically in a horizontal plane about a common centre · CPC title

• H01Q9/28

  Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines (waveguide horns or mouths H01Q13/00; slot antennas H01Q13/00) · CPC title

• F41H11/12 Primary

  Means for clearing land minefields; Systems specially adapted for detection of landmines · CPC title