| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure of a fixed part of an antenna element capable of securely and reliably fixing the antenna element by allowing a pointed head at each of two right and left lined ribs within a boom to cut into a circumferential wall of a corresponding antenna element.SOLUTION: At each of inner surface of right and left walls in a tube wall of a boom, two lined long ribs are arranged in parallel to the direction of axis of the boom with a gap formed in vertical direction mutually. The rib is formed in a chevron shape so that a top part may be formed at a side near each partner's rib. The diameter of a tube wall hole is formed wider than a gap between the top parts of the two right and left lined ribs. In addition, the top part of the rib is broken off at a position where each tube wall hole is prepared. Each of eight pointed heads in the two right and left lined ribs is cut into a circumferential wall of the corresponding antenna element. Using the eight pointed heads, the antenna element is fixed to the boom while the antenna element is prevented from turning and moving in an axial direction. |
