| 摘要 |
PURPOSE:To attain deep drawing and to prevent the reduction in the minimum resonance frequency and generation of abnormal sound, by impregnating a thermosetting resin on a base cloth woven to be a hexagonal shape while twisting threads and heat and press forming the base into a prescribed corrugation shape. CONSTITUTION:The outer circumference of a voice coil coupling section 1 is formed with a corrugation section 2 and a skirt section 3 is provided downward to the circumference a connection part 4 is provided for the framing to the circumference. As the base cloth 5, >=1 or 2 pieces of cotton threads or synthetic threads 6 are formed by weaving the threads into hexagonal shape while twisting the threads mechanically and alternately. The longitudinal and lateral threads of the close do not shift at every cross point. A thermosetting resin such as phenol resin is impregnated to the cloth 5 and said constitution is obtained by heating and pressing. The directivity of the cloth is very less, and the forming of the damper with deep corrugation is possible, the deformation of the damper is less and excellent linearity is obtained. |
