| 摘要 |
PURPOSE:To obtain the vibration detector with a simple constitution, by detecting the relative displacement between a fixed magnet which is fixed at the bottom of a cylindrical container and a traveling magnet which is floated in the container as the variation in density of interlinked magnetic fluxes, by using a coil. CONSTITUTION:The fixed magnet 3 having the magnetic poles in the vertical direction is fixed to the bottom of the cylindrical container 1. A lid 2 for hermetical sealing is fixed at the top of the container. In the cylinder, the traveling magnet having the magnetic poles in the vertical direction is coupled so that it repels the fixed magnet 3, and can slide freely. A coil 5 is wound around a suitable position at the outside of the cylindrical container. In the case this detector is attached to an internal combustion engine, the traveling magnet 4 is vibrated in consonance with the vibration of the engine, the density of the fluxes which are interlinked with the coil 5 is varied, and the voltage corresponding to said magnetic flux variation speed is induced. The frequency is the same as that of the engine. By counting the voltage signal, the number of rotation can be obtained by the simple constitution. |
