| 摘要 |
<p>PURPOSE: To protect the antenna housing against the pressure of earth and sand or water and to enhance the efficiency in the maintenance work of a dielectric resin plate by providing a joint, having a level difference, at the opening of a metal housing and coupling the dielectric resin plate. CONSTITUTION: A joint 20 having level difference parts 24, 25, is welded to the opening of a metal housing 10 and a dielectric resin plate 21 is fitted to the level difference part 24. Another dielectric resin plate 22 is coupled with an antenna housing 11 having a flange 26 disposed in the metal housing 10 and fitted to the level difference part 25. Since the level difference at the part 25 is larger than the total thickness of the flange 26 and the dielectric resin plate 22, a gap appears between the dielectric resin plates 21, 22 fitted to the joint 20. Consequently, the dielectric resin plate 22 can be protected even if the dielectric resin plate 21 is subjected to external pressure of earth and sand or water and pressed. Furthermore, the antenna housing 11 is provided with vibration resistance.</p> |
