GB334186A - Improvements in and connected with the manufacture of glass containers - Google Patents

Abstract

334,186. Forster, A. C. May 27, 1929. Blowing hollow-ware. - Relates to the manufacture of glass bottles or jars of the kind in which a ledge is formed around the inside of the mouth to form a seating for a closing device, such as bottles for holding foodstuffs or milk. According to the invention, a ring mould used in a machine for making this ware is so formed that the, glass which constitutes the seating is prevented from being deformed by the action of the air when a parison is blown to a finished bottle. The ring mould comprises an outer portion 2 made, as usual, in hinged sections, and an inner sleeve 3 by which the seating at the mouth of the bottle is formed. The sleeve 3 has a cylindrical extension 3<x> which lies within the cylindrical casing 4 of the mould mount. A mouth-forming plug 5 slides in a cylindrical cavity in the sleeve 3, and its base normally rests on a flange 6 on the sleeve and is kept in place by springs 11, 12. A tubular spindle 7, screwed into the plug, allows air to be blown into the mould through passages 16 in the plug. The sleeve 3 is formed with a cylindrical top portion 15 and a ledge 14 which forms the seating at the mouth of the bottle. In use, molten glass is fed into the parison mould 1 in the usual way and is forced by compressed air or suction down into the space surrounding the sleeve 3, the plug 5 being raised to the position shown in dotted lines. The plug is then lowered, and air is blown into the space thus formed to expand the glass. During this operation, the glass is drawn away from the top of the part 15 of the sleeve 3 by the stream of air passing up around the plug, but the glass on the ledge 14 is protected by the part 15 and is not deformed. The seating thus formed in the mouth of the bottle remains flat, and an airtight joint can be formed with a closure device.