GB1400844A - Arrangement for determining the deviation in the position of a railway track from its ideal position - Google Patents

Abstract

1400844 Level and curvative of railway tracks FRANZ PLASSER BAHNBAUMASCHINENINDUSTRIE GmbH 5 Oct 1972 [8 Oct 1971] 45883/72 Headings G1A and G1F [Also in Division B7] In an arrangement for determining or correcting the deviation in the position of railway track in which a reference beam of radiation e.g. a laser beam 7 is directed from a transmitter 6 parallel to the required position of the track past a position at which deviation is to be determined or corrected to a measuring board 11 or radiation receiver, a beam deflecting element is provided at the said position which deflects the beam when any track deviation is encountered. In the levelling arrangement shown in Fig. 1, the beam 7 fans outwards in a horizontal reference plane parallel to the required track plane and the beam deflecting unit is a cylindrical lens 9 having its axis horizontal and extending in the reference plane when the unit is over correctly positioned track. In this latter condition the beam is undeflected and it strikes the board 11 at a predetermined position. Track deviation is measured by the distance the deflecting unit has to be moved to bring the deflected beam to the predetermined position. During track levelling this movement occurs as the track is lifted by track levelling tools. For track alignment a beam which fans in the vertical plane and a cylindrical lens with a vertical axis are used. In the combined levelling and aligning arrangement shown in Fig. 9, laser beam 31 has a crosssection in the form of a cross and is directed, with its horizontal component 31a parallel to the required track plane and its vertical component 31 extending in line with the required alignment of the track, from transmitter 29 via beam deflecting spherical lens 30 at the track position being corrected to a beam sensitive receiver 20. The receiver, Fig. 5, includes light and/or temperature sensitive elements 23 disposed as shown which co-operate with the vertical component 21 of the beam to detect any lateral deflection arising from an alignment error to control tools for track alignment and with the horizontal component 22 of the beam to detect any vertical deflection due to level error to control tools for track levelling. For correcting track in curves, Fig. 6, the beam is directed tangentially to the track from transmitter 15 and deflected by cylindrical lens 17 to measuring board 18. Depending on the distance between points 2, 3 and 4 and the track curve radius the position the beam strikes the board can be determined and if necessary the track at position 3 and the lens are shifted to make the beam strike the board at this position.