GB931613A - Improvements in and relating to vacuum flasks - Google Patents

Abstract

931,613. Vacuum-jacketed vessels. BRITISH VACUUM FLASK CO. Ltd. Feb. 8, 1962 [June 16, 1961], No. 21946/61. Class 64 (2). The integral or separately attached base of an external container 17 for a vacuum flask is of recessed form as at 18 to provide support for a vacuum vessel 25, the latter being retained in position in the container 17 by means of a resilient shoulder 21, e.g. as described in Specifications 866,263, 866,264 and 884,185. A thin non-resilient packing member, e.g. of paper (not shown) may be interposed between the recessed support 18 and the vessel 25. As shown, the container 17 may be a onepiece plastics moulding, e.g. of polystyrene or polypropylene. The mouth of the container 17 includes an integral annular bead 19 directed radially inwards and radially spaced from the outer periphery to provide an abutment face 20. The shoulder 21 is provided with an annular radially outwardly-directed hook-like flange 22 which defines on its inner surface a recess 23 for engaging the bead 19 with a snap-action and abuts at its free end the abutment face 20 of the container 17. The shoulder is formed with inwardly-directed resilient lips 24 bearing directly on the vacuum vessel 25. The base of the container 17 is recessed to accommodate an exhaust nipple on the vacuum vessel 25, the upper part of the base having a profile complementary to the base of the vacuum vessel at their areas of contact. The base may have strengthening radial ribs (Fig. 2, not shown).