DK146994B - Inelastic bottom support in a thermos flask - Google Patents

Description

(19) DENMARK

φ (, 2) PUBLICATION WRITING (ιυ 146994 B

DIRECTORATE OF THE PATENT AND TRADEMARKET SYSTEM

(21) Patent Application No. 3196/78 (51) IntCI.3: A47J 41/02 (22) Filing Date: 17 Jul 1978 (41) Alm. available: 26 Jan 1979 (44) Submitted: 12 Mar 1984 (66) International Application No: - (30) Priority: 25 Jul 1977 SE 770851 »(71) Applicant: SHARE COMPANY * TERMOVERKEN; S-550 03 Joenkoeplng, SE.

(72) Inventor: Sven * Tureseon; SEE.

(74) Plenipotentiary: Chas. Skin (54) Inelastic bottom support in a thermos bottle

The invention relates to a bottom support in a thermos bottle of the type specified in the preamble of claim 1. Thus, the invention is based on a thermo bottle having a thermoglass with a centrally located capillary tube.

OQ

(g) On thermoglass, capillary tubes are required for loading a liquid to provide internal mirror coating of the double-walled thermoglass and to evacuate this fluid and subsequently to evacuate air. Previously, this capillary tube has been positioned near the vertical outer surface of the O thermoglass, whereby clamping pressure has been applied centrally to the bottom surface of the thermoglass. However, this does not provide any protection of the capillary tube from impact, e.g. during insertion of the thermos into a sleeve for the thermos.

In order to improve the mechanical protection of the capillary tube, a transition has been made to surround the lower part of the thermoglass with a ring of metal, which is attached to the lower part of the thermoglass by gluing or using casting material. This attachment makes it possible to apply the clamping pressure to the thermo glass via the metal ring, therefore no pressure is required against the relatively thin glass wall in the bottom of the thermo glass. As a result, the capillary tube has been placed centrally on the bottom of the thermoglass, where it obtains protection in the transverse direction by means of the metal ring.

The metal ring is usually made of rather thin sheet material and is given a stiffening by means of an over approx. the half height from the outside pressed into the groove. This further serves to prevent the solidified fastener placed after the incorporation of the thermoglass or molding from sliding down the inner wall of the ring.

However, the use of this metal ring and its attachment means that several labor and material-intensive manufacturing steps are required. The object of the invention is therefore to provide an inelastic bottom support which, in addition to being easy to manufacture, must simplify the attachment to the thermoglass and nevertheless provide a satisfactory protection of the capillary tube. The solution to this problem is apparent from the measures specified in the characterizing part of claim 1.

According to the invention, the inelastic bottom support thus consists of a plastic tube which encloses the lower part of the thermoglass and which extends some distance along it. Inside the plastic tube there is a transverse wall connecting to the contour on the lower part of the thermos with a hole for the capillary tube. This transverse wall is at such a distance from the lower end plane of the plastic tube that the tip of the capillary tube cannot safely reach this plane.

The upper edge of the plastic tube is preferably tapered to an egg at the point where it abuts against the thermoglass, allowing for a tight connection. In order to compensate for varying diameter dimensions on the thermoglass set, a bead-shaped inwardly thickening can be applied to this egg.

The invention is explained below with reference to the drawing, in which fig. 1 is a schematic sectional view of the lower portion of a thermos bottle; and FIG. 2 a portion of the plastic tube.

A bottom support 1 encloses the lower portion of a thermo glass 2 and has an inner transverse wall 3, the shape of which corresponds to the contour of the lower portion of the thermo glass. The cross wall has a hole 4 through which the capillary tube 5 can freely pass. The lower end plane 6 of the plastic tube 1 is so far from the tip of the capillary tube 5 that it cannot be damaged.

The bottom support does not have to be neither molded nor glued to the thermo glass, but simply raised around its lower part.

Because the lower bottom surface of the thermo glass is largely in contact with the entire transverse wall of the plastic tube, a gentle pressure take-up is ensured by applying a clamping pressure to the thermo glass. This happens e.g. after the thermo glass has been inserted into the sleeve 8 of the thermos by screwing or otherwise affixing a bottom lid 9 against which the bottom support should rest.

The plastic tube is simply inserted over the thermo glass and pressed against its bottom surface. No bonding or casting is required anymore. The plastic tube can be given such dimensions that no deformation at pressure can occur, e.g. towards its lower edge. Such deformation is very common when using a metal ring.

A sealing connection of the upper edge of the plastic tube is achieved if the plastic tube is formed here with a somewhat inwardly resilient egg-like end 7, which as shown in FIG. 2 may have an inwardly projecting bead-like thickness 10 to compensate for varying diameter dimensions on the thermoglass.

The bottom support can be used for different types of thermo bottles and need only be adapted to the dimensions of the thermo glass used.