| 摘要 |
PURPOSE:To prevent the external force to be applied unevenly to a spiral owing to twist of dielectric supporting rods by forming the grooves which guide the dielectric supporting rods, on the innser surface of an outer enclosure. CONSTITUTION:On the inner surface of a cylindrical outer enclosure 6, circular grooves 7-9 which guide dielectric supporting rods 2-4 in insertion and fixation are formed at intervals of 120 deg.. A spiral 1 and dielectric supporting rods 2-4 are inserted into the outer enclosure 6, in a configuration where dielectric supporting rods 2-4 are set in the grooves 7-9. The spiral 1, dielectric supporting rods 2-4, and the outer enclosure 6 are fixed to each other in the state where the elastic force which is proportional to the difference between the inner diameter of the outer enclosure 6 and the outer peripheral diameter formed by the dielectric supporting rods 2-4 is always applied in the direction of center. |
