| 摘要 |
PCT No. PCT/SE81/00283 Sec. 371 Date May 20, 1982 Sec. 102(e) Date May 20, 1982 PCT Filed Sep. 30, 1981 PCT Pub. No. WO82/01312 PCT Pub. Date Apr. 29, 1982.The ear plug (40) includes an elongate body with a rounded tip portion and of an elastic material enveloped by a deep-drawn sheath (41) of thin flexible plastics film material. Rearwardly the plug preferably has a neck portion from which the sheath projects in the form of a stiffer collar or flange. Production of the ear plug includes deep-drawing a thermoplastic film or foil into a sheath with desired thickness distribution, and filling the sheath with elastic material (53). Filling may take place simultaneously with deep-drawing, the body of elastic material constituting a die for deep-drawing in a forming hole (45), or after the deep-drawing. In the latter case, an elastic die body is used to advantage, the shape of which generally corresponds to that of the finished plug, for deep-drawing in a forming hole suited to the die body. |
