| 摘要 |
1522744 Monitoring rail surfaces SPENO INTERNATIONAL SA and FRANK SPENO RAILROAD BALLAST CLEANING CO Inc 4 March 1976 [14 March 1975] 08630/76 Heading G1N The vertical undulations of a rail surface are measured by an accelerometer carried on a rail vehicle, the resulting signals being integrated, filtered and recorded as a function of distance travelled. The signals from accelerometer 4 (Fig. 3) are amplified at 6 and fed through a band pass filter 7 to be double-integrated at 12. The vertical displacements thus obtained are rectified at 13, averaged at 15 and recorded at 20. Large pulses due to e.g. joints in the rail, are eliminated by filter 19 and counted at 22. The pass band of filters 7, 19 is automatically controlled by a speed signal derived from circuit 8. The frequency of the undulations is determined at 25 by counting the zero cross overs of the signal from integrator 12. This is divided at 27 into the speed signal to determine the wavelength of the undulations. The noise developed is picked up by a microphone 31 and recorded at 41. |
