GB885987A - Improvements in or relating to vacuum flasks - Google Patents

Abstract

885,987. Container closures. LESLIESMITH. L. Jan,. 6, 1958 [Jan. 8, 1957; March 7, 1957 ; May 7, 1957 ; July 8, 1957], Nos. 733/57, 7551/57, 14519/57 and 21577/57. Class 125(3). The bottle 3 of a vacuum flask is closed by a stopper 15 and a polyethylene pouring lip member 1 of a form described in a Divisional Specification 885,989, i.e. having screw threading 14 or equivalent inclined surfaces formed on the inner face for co-operation with similar threading or surfaces on the outer face of the stopper. An inwardly-direeted skirt 6 of the lip 1 makes a liquid-tight seal at the bottle mouth while a polyethylene bung portion 16 of the stopper seals the bottle. A ridge 24 around the underface of the stopper rim 20 presses the edge of the lip 1 against the inner face of the rim flange 21. A rigid collar 25 may replace the flange 21 or may merely reinforce the lip. In another form, Fig. 5 (not shown), the bottom of the stopper rim flange has a smaller internal diameter than that of the lip so that it underlies the lip when the stopper has been screwed into position and the flange bottom has jumped the lip edge. The top of the stopper is a separate rigid disc which is a push fit into the hollow bung-and-screw-thread portion as described in a Divisional Specification 885,988, and in the form shown, there is a depending skirt, Fig. 4 (not shown) extending down behind the stopper screw thread for reinforcement. The lip member 1, which may be formed with a second sealing skirt 8, may be extended downwardly to form the shoulder of the flask canister. The second Provisional Specification describes also a canister shoulder having an upstanding sleeve for external support of the pouring lip screw threading. The third Provisional Specification describes a stopper without screw threading but which clips over the lip. Specification 818,541 also is referred to.