Method and apparatus improved in order to detect the cracks or fissures hidden, which may exist in the metal bars, in the rails or in any other similar elements.

摘要

290,073. Jackson, F. R., (Sperry Development Co.). July 22, 1927. Pens for recording-instruments.-In apparatus for detecting flaws in metal bars, rails, &c., a relay controls the circuit of a recording pen shown in Fig. 13, comprising an electromagnet 36 and a spring arm 37 which carries at its free end a U-shaped pen 38, the inner end of which dips into an ink trough 39. A series of such pens may be mounted adjacent to one another with the magnets staggered, as shown. The pens mark on a chart which is driven from the car wheels, so that the location of a flaw may be scaled off from the chart. A polarized recording pen is shown in Figs. 4 and 4a, in which a U-shaped magnet 120 is energized by a continuous current and a coil 421 is in circuit with or controlled by the amplifier. A spring plate armatures 122 pinned at its base projects through the coil 421 and between the ends of the U- shaped magnet, and has a pin 123 engaging a slot in the reed 125 which holds the pen 461. A flaw causes motion in one direction, while bad or broken contact at the brushes causes motion in the other direction.