Station measuring natural frequencies - is for mechanical bar resonators supported by air bearings and excited by hammer

摘要

A measuring station is for natural frequencies of mechanical bar resonators. The station has a holder holding the resonators with low damping, a device exciting oscillations in resonators and a microphone converting acoustic oscillations emitted by the resonators into electric oscillations whose frequency is analysed. The oscillation generator is in the form of a mechanical hammer released by a rotating magnet. It consists of a spring-mass system, and the resonator (2) holder has radial air bearings (5, 6) supporting the resonators at their oscillation nodal points without contact. An axial air bearing (4) supports the resonators at one of their butt-end surfaces.