Direct display of thermal conductivity profile for non-destructive testing of insulated rocket motor cases

Claim 1

An easily interpretable display of insulation flaws system comprising an insulated object to be examined; radiation sensing means positioned such that a small area of the insulated object will be sensed at one point in time; moving means connected to said insulated object and said radiation sensing means for moving them relative to each other such that said radiation sensing means will scan a predetermined area of said insulated object; display means connected to an output of said radiation sensing means such that the area scanned will be displayed; said display means is an oscilloscope having X and Y scan and input terminals said radiation sensing means having an output connected to the Z input terminal of said oscilloscope such that it will intensity modulate the display of said oscilloscope; raster circuit means being connected to said X and Y input axes such that the area of display will correspond to the area scanned on said insulated object; said radiation sensing means is an infrared detector and said insulated object is a thin-wall insulated rocket motor case; said raster circuit means comprises a waveform generator having a long gentle slope output and a vertical sweep circuitry having a sawtooth output; amplifiers connected between the raster circuits and the X and Y input terminals of the oscilloscope; said vertical sweep circuitry comprises a constant current source connected directly to said Y axis; a capacitor connected in parallel with said constant current source; a reset switch being connected in parallel with said constant source and said capacitor; and synchronizing means connected to said reset switch and said moving means such that it will be periodically closed for a short period of time in synchronism with the scan of the insulated object.