CONDOM (VERSIONS), METHOD OF ITS MANUFACTURE, CONDOM AND APPLICATOR SYSTEM, PROCESS OF PRESERVATIVE ARTICLE FORMATION Russian patent published in 1999 - IPC

FIELD: prophylaxis of venereal diseases. SUBSTANCE: condom has circular thin-film packing element placed inside tubular casing. Packing element has hole which size is smaller than open end of casing. Packing element is coupled to casing over its external periphery. In operating position the element is perpendicular to longitudinal axis of casing. Condom manufacturing process includes bending of flexible material sheet along its length with overlapping of sheet sections. Then folded sheet is welded along its side peripheral fields and distant edge. Prior to coupling, input fold with central hole for formation of membrane jumper is additionally made along bending line. Preservative article is formed due to peripheral thermal coupling of overlapped thermoplastic sheet parts along longitudinal fields and distant edge of sheet. Parts of thermoplastic sheet are folded over flexible ring preliminarily stretched in longitudinal and external directions. After thermal coupling, article is turned inside out. One of article formation versions uses thermal fastening element on which tube made of thermoplastic film is pulled. After thermal coupling of folded sheets is performed stretched tube is welded to internal surface of open end of sheets with formation of article flexible binding. In version of bag-shaped condom manufacture half-finished article is placed in larger-diameter hollow and inflated through open end. This done, while keeping open end of half-finished article nonheated, the rest of half-finished article is heated up to its fitting to dimensions of hollow. In one of condom versions middle part of casing may be folded longitudinally, moved inside, spot-welded or coupled loosely so that condom length may be enlarged by stretching of its middle part. EFFECT: reduced hazard of contamination with veneral diseases, enhanced efficiency in use and manufacture. 17 cl, 36 dwg