US 4,072,895 A · Eddy current converter for non-destructive testing of electrically conducting coating in holes of printed circuit boards

Abstract

The proposed eddy current converter for non-destructive testing of electrically conductive coating in holes of printed circuit boards comprises a cylindrical frame enveloped by an exciting winding and a measuring winding and inserted into a hole of a printed circuit board being tested. The coils of the exciting and measuring windings extend along the generatrices of the cylindrical frame. With the use of the proposed converter, the testing accuracy is independent of the parameters of respective contact areas of a hole being tested. The converter of the present invention is sensitive to the most undesired flaws like transversely extending cracks.

Claims3

Dependent claims

An eddy current converter for non-destructive testing of electrically conducting coating in holes of printed circuit boards, comprising:

a cylindrical frame inserted in a hole being tested of a printed circuit board;
a winding enveloping said cylindrical frame, said winding being inserted for testing together with said cylindrical frame into said hole of the printed circuit board being tested, said winding when energized inducing eddy currents in said coating and sensing the induced eddy currents;
and
conductors of said winding extending in an axial direction all over the surface of said cylindrical frame the axial length of the conductors and cylinder being greater than the depth of the holes of the printed circuit boards.

1 more element

Dependencies are inferred from the claim text.

Eddy current converter for non-destructive testing of electrically conducting coating in holes of printed circuit boards

Life of this patent

Eddy current converter for non-destructive testing of electrically conducting coating in holes of printed circuit boards

Life of this patent

Abstract

Claims3