摘要 |
In an electrically powered mechanism for expanding and contracting antenna in which an operation strip coupled to antenna overcoat members that are telescopically connected to expand or contract, is expanded or contracted by a rotary member driven by a motor, and the operation strip has a width greater than the thickness thereof, and has arcuate surfaces or flat surfaces; the rotary member is rotatably provided in a case body which is provided with an annular guide portion with a guide groove for guiding the operation strip to the side of the drum and to the side of the antenna overcoat members, and a strip-receiving groove is formed along said rotary member into which the operation strip is fitted; and the operation strip is fitted in a curved manner to the strip-receiving groove, and a torque for delivering or pulling the operation strip when the rotary member is roated is so selected as to produce a required holding force depending upon the thickness of the operation strip, the radius of curvature of the strip-receiving groove and the width of the strip-receiving groove. |