Northrop Grumman Systems Corporation

Mark David Brown

John W Tully

David Arthur Luippold

Kent KinMan Tam

Leon Burks, Jr

George V Case

Susan LaColla Wade

A non-destructive, inline, multi-channel fabric conductivity measurement system uses an array of opposing paired transmit/receive microwave horns on opposite sides of a fabric material moving in a production line, each horn pair corresponding to a channel in the system. A processor-based controller can control channel hopping, frequency hopping, and measurement orientation to acquire measurements of material conductivity and anisotropy, which measurements can be analyzed for defects that can be flagged in real time during production. Measurements and/or analyses can be stored to make roll-to-roll, batch-to-batch, day-to-day, or production-phase-to-production-phase comparisons useful in identifying the sources of production problems and/or the causes of corrections.

Inline fabric conductivity measurement

A highly conductive thermoplastic elastomer gap filler having superior durability and EMI shielding properties. According to the preferred embodiment, the TPE comprises graphite fiber having a nickel-copper-nickel coating formed thereabout that is suspended within an elastomer, which preferably comprises polyvinylchloride. The TPE of the present invention is particularly well-suited for reducing radio frequency electromagnetic radiation reflected by gaps formed between adjacent panels of a structure, and is particularly well-suited for the maintenance and repair of low observable aircraft. The TPE of the present invention may further be modified to include carbon black filler.

Highly conductive thermoplastic elastomer (TPE) gap filler

A hot-melt fastener filler placeable within a void atop an in-place fastener countersunk within a surface such as an exposed aircraft surface. The filler includes an electrically-conductive mat fabricated of at least one ply having a plurality of non-woven electrically conductive fibers each having a core strand coated with a nickel layer, preferably coated with two additional layers of copper and nickel, and generally uniformly dispersed within a thermoplastic elastomer. Electrically conductive carbon black particulate can be distributed throughout the elastomer, and the mat preferably is fabricated of two plies oriented at 0&deg; and 90&deg; to each other. A pressure sensitive adhesive can be provided on one side of the sheet to thereby permit secured placement prior to completion of installation. The fastener filler allows not only regularly scheduled maintenance, but also permits quick and generally uncomplicated field-level repairs for assuring equipment availability at remote sites.

Hot melt fastener filler

Highly conductive elastomeric sheet. Preferably, the conductive elastomeric sheet comprises a conductive wire mesh loaded into an elastomeric matrix from which is also loaded with a conductive particulate. Preferably, the particulate comprises carbon particulate having a sub-micron size, and is present in an amount between ten percent (10%) to twenty percent (20%) by volume. The conductive elastomeric materials are exceptionally durable and retain a high degree of conductivity well-after ten thousand (10,000) fatigue performance cycles.

Highly conductive elastomeric sheet

A highly conductive thermoplastic elastomer (TPE) gap filler having superior durability and EMI shielding properties. According to the preferred embodiment, the TPE comprises graphite fiber having a nickel-copper-nickel coating formed thereabout that is suspended within an elastomer, which preferably comprises polyvinylchloride (PVC). The TPE of the present invention is particularly well-suited for reducing radio frequency electromagnetic radiation reflected by gaps formed between adjacent panels of a structure, and is particularly well-suited for the maintenance and repair of LO aircraft. The TPE of the present invention may further be modified to include carbon black filler.

Growing community of inventors

San Pedro, CA, United States of America

Mark David Brown