Measuring blade tip vibration amplitude with a temperature resistant fibre optic detector

摘要

A device for measuring vibration amplitudes of the blade tips in a turbomachine, comprises a support 16 mounted in an orifice of a casing of the turbomachine and wherein are housed two optical guides 20, 22 for the emission and reception of a light signal exiting inside the casing across from the tips (26, figure 1) of the blades of a turbine wheel. Each optical guide 20, 22 comprises an optical fibre 61, 62 connected by a mechanical connector 64 to a needle 65, 66 of which the core (70, figure 6) is made of a material (e.g. sapphire) able to transmit a light signal and which is resistant to temperatures of 1100 °C and which exits at its distal end in the casing (12, figure 1) across from the blade tips.