GB1051711A - - Google Patents

Abstract

1,051,711. Track levelling apparatus. CANADA IRON FOUNDRIES. June 1, 1963 [Feb. 8, 1963], No. 12853/63. Heading B7N. [Also in Division G1] Track levelling apparatus comprises a high frequency beam transmitter, such as an infrared beam transmitter 11, Fig. 1, mounted on a self-propelled truck 10 for movement along the track above the grade rail and transmitting a cone-like beam longitudinally of the track, a pair of beam receivers 15a, 15b on a carriage 14 one above each rail, for movement along the track in spaced relationship to the transmitter 11, a pair of shadow boards 20 mounted on railengaging wheels 21 on a frame 22 connected to the front of carriage 14 and a pendulum or other gravity sensing device controlling devices for adjusting the height of one of the receivers 15a, 15b so as to maintain one of them in cross level relative to the grade rail. As shown, two transmitters 11 are provided but only one is in use at a time depending on which is the grade rail. The two receivers 15a, 15b may be mounted by brackets 30, Fig. 2 (not shown), on screw jacks 24a, 24b, operated by motors 26, 26b, the brackets 30 being connected by a cross-bar 31 carrying a casing 34 which houses a pendulum. In use if the receivers 15a, 15b are open to the transmitted beam both rails will be jacked and when one receiver has been obscured from the beam by the raising of its shadow board 20 the jacking of the associated rail is stopped. If the pendulum within casing 34 swings away from its central position one of a pair of switches is closed and motor 26 or 26b is operated to raise or lower one of the receivers 15a or 15b until it is in cross level relative to the grade rail. In a modification the pendulum and switches are replaced by a gravity sensing electrolyte potentiometer, bridge and phase sensitive amplifier.