Shaft rotation rate sensor for turbine engines.

摘要

A shaft rotation rate sensor 50 for turbine engines. A reflective radial grating 66 on the surface of the turbine shaft 70 is employed in conjunction with an electromagnetic wave source 52 and beam combining elements to mix two beams of frequency f and f +/- DELTA f, where DELTA f is proportional to the rotation rate of the grating 66. The source energy is reflected off the grating 66, and the zero-th and first order transmission from the grating 66 are mixed to give the beat frequency proportional to the rotation rate. The sensor 50 has no moving parts. <IMAGE>