Magnetic inspection systems for inspection of target objects

Patent metadata

Field	Value
Publication number	US-9759686-B2
Application number	US-201414166367-A
Country	US
Kind code	B2
Filing date	Jan 28, 2014
Priority date	May 13, 2011
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Inspection systems provided herein include drive coils capable of being excited to generate a substantially uniform magnetic field about an object. The object includes a ferromagnetic adhesive adhered thereto. The inspection systems may also include an array of sensor coils adapted to detect the magnetic field from the drive coils after the magnetic field interacts with the ferromagnetic adhesive and to produce a voltage output corresponding to the detected magnetic field.

First claim

The invention claimed is:

1. An inspection system, comprising:
a plurality of drive coils each configured to generate a substantially uniform magnetic field through an object; and
a plurality of sensor coils each configured to detect the magnetic field from a single respective one of the drive coil of the plurality of drive coils after the magnetic field interacts with the object and to produce a voltage output corresponding to the detected magnetic field;
wherein a first layer of the inspection system supports a first array of the drive coils and a first array of the sensor coils, wherein each sensor coil is positioned between two adjacent drive lines, the drive coils comprise drive lines and wherein the first layer is offset from at least one additional layer of the inspection system that supports at least one additional corresponding array of the drive coils and at least one additional corresponding array of the sensor coils, wherein each sensor coil in the at least one additional corresponding array of the sensor coils is positioned between two adjacent drive lines in the at least one additional corresponding array of the drive coils, and further wherein the offset is in a direction of the first array of the drive coils and the first array of the sensor coils, and
further wherein the first layer and the at least one additional layer of the inspection system avoid a blind zone.

2. The inspection system of claim 1 , wherein the plurality of drive coils are connected to one or more multiplexer circuits disposed on a circuit board.

3. The inspection system of claim 1 , wherein the plurality of sensor coils are connected to one or more multiplexer circuits disposed on a circuit board.

4. The inspection system of claim 1 , wherein the plurality of drive coils comprise substantially circular, planar drive coils having a diameter between approximately 3 inches and approximately 7 inches.

5. The inspection system of claim 1 , wherein at least some of the drive lines comprise parallel drive lines.

6. The inspection system of claim 1 , wherein at least some of the drive lines comprise an anti-parallel drive configuration wherein the drive line comprises a multiple turn and multilayer format that enables alternating magnetic flux directions between two adjacent set of drive lines.

7. The inspection system of claim 1 , comprising processing circuitry configured to convert the voltage output into a digital signal representative of the object features and to display the digital signal on a monitor.

8. The inspection system of claim 1 , wherein the plurality of drive coils are configured to be excited sequentially, one at a time.

9. The inspection system of claim 1 , wherein the object comprises an adhesive doped with magnetic material and configured to interact with the substantially uniform magnetic field produced by each of the plurality of drive coils.

10. The inspection system of claim 1 , wherein the object comprises an adhesive doped with magnetic material and adhered to a wind blade joint.

11. The inspection system of claim 1 , wherein the plurality of drive coils comprises one or more subarrays and each of the one or more subarrays is configured to be excited simultaneously.

12. An inspection system, comprising:
a plurality of drive coils each configured to generate a substantially uniform magnetic field through an object; and
a plurality of sensor coils each configured to detect the magnetic field from a drive coil of the plurality of drive coils after the magnetic field interacts with the object and to produce a voltage output corresponding to the detected magnetic field, wherein the plurality of sensor coils comprises a sensor coil array comprising at least two subarrays of sensor coils, wherein each subarray of sensor coils is dedicated to a corresponding drive coil of the plurality of drive coils and is configured to detect the magnetic field generated by the dedicated corresponding drive coil of the plurality of drive coils after the magnetic field interacts with the object,
wherein a first layer of the inspection system supports a first array of the drive coils and a first array of the sensor coils, wherein each sensor coil is positioned between two adjacent drive lines, the drive coils comprise drive lines and wherein the first layer is offset from at least one additional layer of the inspection system that supports at least one additional corresponding array of drive coils and at least one additional corresponding array of the sensor coils, wherein each sensor coil in the at least one additional corresponding array of the sensor coils is positioned between two adjacent drive lines in the at least one additional corresponding array of the drive coils, and further wherein the offset is in a direction of the first array of the drive coils and the first array of the sensor coils, and
further wherein the first layer and the at least one additional layer of the inspection system avoid a blind zone.

13. The inspection system of claim 12 , wherein the plurality of drive coils are connected to one or more multiplexer circuits disposed on a circuit board.

14. The inspection system of claim 12 , wherein the plurality of sensor coils are connected to one or more multiplexer circuits disposed on a circuit board.

15. The inspection system of claim 12 , wherein at least some of the drive lines comprise parallel drive lines.

16. The inspection system of claim 12 , wherein at least some of the drive lines comprise an anti-parallel drive configuration wherein the drive line comprises a multiple turn and multilayer format that enables alternating magnetic flux directions between two adjacent set of drive lines.

17. The inspection system of claim 12 , comprising processing circuitry configured to convert the voltage output into a digital signal representative of the object features and to display the digital signal on a monitor.

18. The inspection system of claim 12 , wherein the object comprises an adhesive doped with magnetic material and adhered to a wind blade joint.

Assignees

• Gen Electric

Inventors

• Godbole Mandar Diwakar
• Wang Changting
• May Andrzej Michal
• Tralshawala Nilesh
• Faidi Waseem Ibrahim

Classifications

• G01N27/82 Primary

  for investigating the presence of flaws · CPC title

• G01N27/904 Primary

  with two or more sensors · CPC title

• G01R33/12

  Measuring magnetic properties of articles or specimens of solids or fluids (involving magnetic resonance G01R33/20) · CPC title