| 摘要 |
PURPOSE:To provide a heat resistant insulated electric wire without fear of degradation of insulation and dielectric breakdown by dividedly absorbing the difference in thermal expansion between a conductor and insulation of each of a plurality of insulation layers. CONSTITUTION:Insulating material 2c, 2b, 2a and a reinforcement 3 are laminated upon a conductor 10. At room temp. no thermal stress will act between the insulating material 2 and reinforcement 3, and the perforation 5 which is brittle should remain without any abnormality, and a specified dielectric withstand voltage will be kept. When a heat cycle is applied, a tensile stress is generated in longitudinal direction due to the difference in the coefficient of thermal expansion between the conductor metal 10 and the inorganic insulating substance of tape 1. Because the pieces of insulating material 2a, 2b, 2c are slidable, the difference in thermal expansion is dispersed in the insulating material 2a, 2b, 2c of different layers, and therefore, a crack is initiated at the perforation 5 to cause generation of ruptural gaps 12a, 12b, 12c. However, these positions differ between laminated insulating pieces 2a, 2b, 2c as adjoining, and electric bridging from the conductor 10 will not be generated by setting the mutual distance good greater than the anticipated difference 12 in the thermal expansion, and thus no drop of insulating performance should occur. |
