Abstract: A brush holder assembly for electrically-coupling relatively movable conductors comprises a brush holder having a cavity which slidably receives a brush and having a pair of shoulders located on opposite sides of the cavity to confront a conductor. An electrically-conductive twin coil spring is mounted in the cavity with its saddle portion engaging one end of the brush and its coils disposed adjacent the shoulders for biasing the other end of the brush into contact with the conductor. An electrical contact member is interposed between at least one of the shoulders and its engaged spring coil to provide a current path into the side of the brush adjacent the coil for improving the overall performance of the brush assembly.

Abstract: A brush holder assembly which affords ready removal and replacement of brushes is disclosed. The assembly comprises a guideway in a housing for slidably receiving a brush holder, latching means on the guideway and holder to secure the holder with the brush in operating relation in the housing, and means displaceable between the holder and the guideway from outside the housing to unlatch the holder to permit the brush and spring carried thereby to be withdrawn from the housing.

Abstract: The testing of an article for deviations thereof from an optimum thickness range includes scanning the article by means of a thickness measuring device; making a plurality of thickness measurements of the article during each scan; averaging successive groups of a predetermined number of theoretical measurements during each scan; comparing the averages so obtained with predetermined desired averages and marking a visual record with symbols indicative of whether each group is within, greater than, or less than the desired average.

Abstract: An arrangement for testing tube-like articles for defects includes scanning a defect detecting device in a helical path about the article; marking, upon receipt of defect indicative signals at the device, a pictorial record of the magnitude and position along the article of defects shown by the received defect indicative signals if they are greater than a predetermined magnitude; subjecting received defect indicative signals greater than said predetermined magnitude to predetermined repetition tests; and marking on the pictorial record the circumferential position about the article of defects shown by the received defect indicative signals if they satisfy the predetermined repetition tests.