Method of producing leaky coaxial cable
AssigneesAllied Corporation, Senstar Security Systems Corporation
InventorsHugh A. Edwards, John W. Patchell
Life of this patent
Estimating the term…
Abstract
A method of producing a leakage graded coaxial cable having a braided shield, in which ends of the shield wire are dropped as braiding progresses. Gaps in the shield having progressively increasing size are produced through which the radio frequency field leakage occurs, which facilitates providing a constant radio frequency field around the cable. The cable is coated with a jell flooding agent prior to extrusion of its protection jacket, which fills the interstices and gaps of the shield, and solidifies to a waxy, semi-resilient consistency. The resulting cable can be coiled and flexed, maintaining its shield reliability, and rejects water and fluids in case pinholes in the jacket occur.
Claims14
A method of making a leaky coaxial cable comprising:
- (a) preparing a conductive axial wire covered by an insulating dielectric,
- (b) progressively braiding a conductive braid shield around the dielectric, and
- (c) dropping ends of the braid according to a predefined schedule for successive lengths of the braid shield, to produce progressively larger gaps in the braid shield as the ends are dropped whereby graded leakage of signal carried by the cable is facilitated.
A method of making a coaxial cable comprising:
- (a) progressively drawing a conductive axial wire covered by a cellular polyethylene insulating dielectric through a shield braiding machine,
- (b) braiding a conductive wire shield around the dielectric using wire ends supplied from a plurality of bobbins carried on the machine,
- (c) cutting wire ends from predetermined ones of the bobbins,
- (d) braiding the shield using the same lay angle and continuing with the same braiding schedule, but without the cut ends, while continuing to draw the dielectric and shield covered wire through the machine,
- whereby gaps in the shield braid along the cable are produced.
A method of making a leaky coaxial cable comprising:
- (a) preparing a conductive axial wire covered by an insulating dielectric,
- (b) progressively braiding a conductive braid shield around the dielectric,
- (c) dropping ends of the braid according to a predefined schedule for successive lengths of the braid shield, and
- (d) braiding insulative fillers in the braid in place of the dropped braid ends,
- whereby progressively larger gaps in the braid shield filled by insulated fillers are produced as the ends are dropped and graded leakage of signal carried by the cable is facilitated.
Dependencies are inferred from the claim text.