Patent ID: 6370945
Filing Date: 2002-04-16
Classification: F17D,G01M

Abstract:
A leak detection system for an elongate body, said leak detection system comprising:(a) first and second electrically conductive layers separated by an insulative layer, one of said first and second conductive layers defining said body and the other of said first and second conductive layers being disposed about a substantial portion of the perimeter of a transverse cross section of said body; (b) a circuit coupled to said first and second conductive layers for determining changes in capacitance between said first and second layers, said circuit comprising: (i) an oscillating circuit coupled to said first and second conductive layers for providing a first AC voltage signal (ii) an integrating circuit to said oscillating circuit and to said first and second conductive layers for producing a second AC voltage signal which is an integrated product of the first AC voltage signal; (iii) a detection circuit coupled to said integrating circuit for detecting the peak to peak amplitude of the second AC voltage signal produced by said integrating circuit; and (iv) a response circuit coupled to said detection circuit for triggering a predetermined response when the peak to peak amplitude of said second AC voltage signal produced by said integrating circuit exceeds a predetermined value.