| 摘要 |
PURPOSE:To perform stable, sensitive, highly accurate detection of the displacement of the rail regardless of weather, by regarding the rail as an iron core and providing an exciting coil and detecting coils so as to form a differential transformer. CONSTITUTION:At the locations which have a specified height (h) over the top part of the rail 1, a primary coil 11 and secondary coils 12a and 12b are arranged on a truck of a measuring car. Both coils are air core coils. Their axial direction is horizontal and perpendicular to the rail 1. The rail 1 functions as if it were the core in the differential transformer. When the primary coil 11 is excited by an AC, the secondary coil are magnetically coupled by magnetic lines of force H. Since both secondary coils are differentially connected, the output becomes zero when the rail is located at the central position between both coils. When the rail is displaced in the horizontal direction, the detected signal corresponding to the amount of the displacement is outputted. |
