| 摘要 |
PURPOSE:To enlarge the frequency range capable of preventing the vibration and noise by forming at least one of spring-constant variable layers, which is constituted of an elastomer having a particular glass transmission point and a heating member disposed on the surface of the elastomer or inside thereof. CONSTITUTION:An elastic member 4 is disposed between an upper holding plate 2 and a lower holding plate 3. The elastic member 4 is constituted of fixed layers 5, of which principal ingredient is crude rubber, and spring-constant variable layers 6, which is made of polynorbornane with the glass transmission point ranging from 10 deg.C-50 deg.C and contains thread-like heating elements 7 therein, and then, direct current is applied from a power source 9 through a lead 8. Thereby, in the unenergized state, the elastic member 4 possesses an inherent spring constant, which is the composition of those of the spring-constant variable layers 6 and the fixed layers 5, so as not to resonate with the vibration due to an engine during the ordinary rotation, while at the time of energizing, the elastic member 4 possesses such a spring constant as not to resonate with the vibration due to the engine during the high speed rotation. Therefore, it is possible to enlarge the frequency range capable of preventing the vibration and noise. |
