Abstract: Apparatus and method to detect corrosion in metal junctions. Corroded metal junctions are usually discovered by visual inspection. The present invention detects corrosion in metal junctions when it is not visually apparent. A corroded metal junction acts as a nonlinear device. It generates harmonics and other nonlinear products (such as intermodulation) of any signals applied to the junction. The presence of relatively high level harmonics and/or intermodulation products indicates directly that corrosion has occurred. To detect corrosion in a metal junction, one couples a fundamental frequency signal (f0) into the junction and tests for harmonics of that frequency, especially the third harmonic. Harmonic frequency signals that are relatively large (i.e., above the harmonics generated by the testing system) indicate the presence of corrosion. Measurements to determine if a metal junction is corroded are performed without disturbing the junction.

Abstract: A speed retarding governor particularly adaptable to a carriage of a typewriter wherein the speed of a traversing typewriter carriage is retarded by the cooperation of a plurality of arcuate pivotless lightweight flyweights that are floatably disposed within a cylindrical governor housing. A drive pin fixed to a rotating typewriter escapement toothed drive wheel engages an end of a first flyweight which abuts a second flyweight whereby both flyweights rotate therewith. The centrifugal force thus generated forces the two felt-lined flyweights outwardly against the internal peripheral surface of the governor housing which has now been rendered stationary, to produce a retarding force necessary to retard the speed of the traversing carriage.

Abstract: A pulley for a high speed positive drive system for business machines. The uppermost contour of the teeth of the pulley in combination with the contour of the valleys therebetween, when functionally engaged by a standard positive drive timing belt, provides a quiet running power transmission drive system.