GB688876A - Improvements relating to the manufacture of hollow glassware - Google Patents

Abstract

688,876. Manufacture of hollow glassware. SMITH, A. E. Dec. 29, 1950 [Jan. 25, 1950], No. 31580/50. Class 56. Hollow glass parisons are formed by delivering a first charge 13 of molten glass downwardly into the cavity of a mould 10, compacting the charge downwardly by gaseous pressure into conformity with the shape of the lower end portion of the mould, subsequently delivering at least one further charge 15 of molten glass downwardly into the mould so that it unites with the first charge, and quickly moving a pressing member 16 upwardly in the mould to press the combined charges internally into conforming contact with the walls of the mould cavity. The first charge is preferably small and sufficient to form only the neck or rim finish, and the temperature of this charge as delivered may be higher than that of the subsequent charge, in certain cases however the temperature of the second charge is the higher. Fig. 1 shows a divided body mould 10 embraced by a divided neck mould 11 with a reciprocable neck pin 12 which forms a starting cavity in the glass 13. The glass 13 is compacted by pressure from a blowhead 14 and/or by suction from below. The blowhead 14 and plunger 12 are then removed, the second charge 15 added, and plunger 16 moved upwardly so that the tip of the plunger enters the cavity in charge 13 at or about the same time that charge 15 meets charge 13. Plunger 16 continues upwardly and a cover 17 is applied-to the top of the mould so that the glass fills the mould. The plunger 16 is then removed, the mould and parison inverted, and the parison transferred to a finishing mould and blown to the required shape. The cover 17 may be omitted to produce a parison without a baffle seam, for example for perfumery ware. The production of wide-necked jars is also illustrated. Figs. 13 and 15 show stages in the manufacture of articles with handles, the parison mould halves being formed with grooves 20 which co-operate to form the shape of the handle, vent holes 21 being provided. The parison is blown in a finishing mould 19 formed with mating grooves to receive the handle, and the cavity formed by the grooves communicates at both ends with the interior of the main cavity of the mould. The parison may be prepared at different stations of a rotary machine and then be transferred to a further rotary machine for blowing &c. Specification 547,474 and U.S.A. Specification 2,289,046 are referred to.