RU2444272C2 - Vessel with double walls and vacuum between them - Google Patents

Abstract

FIELD: personal use articles.

SUBSTANCE: invention relates to domestic appliances, namely, to devices for storage and heating of food products. The vessel with double walls and vacuum between them is characterised by the fact that between the double walls there is an elastic reservoir with a coolant, which contacts one wall and may contact two walls in heated condition.

EFFECT: invention makes it possible to vary temperature of vessel content by means of thermal exposure of its external wall and elastic reservoir.

4 cl, 1 dwg

Description

The invention relates to household appliances, and in particular to devices for storing and heating food.

The purpose of the invention is to improve the operation of a device known as a Dewar vessel (US patent No. 872795 from 12/03/1907), making it possible to change the temperature of the contents of the vessel by thermal exposure to its outer wall, while maintaining the insulating properties.

During the patent search, several inventions were discovered that partially solved the problem.

A technical solution is known according to the USSR copyright certificate No. 1681836, class. A47J 41/00, 1988 for the invention of Thermos. Thermos contains a housing in the form of a Dewar vessel and an electric heater. The heater is made in the form of a semiconductor film deposited on the outer surface of the inner vessel. The disadvantage of this device is the inability to change the temperature of the contents of the vessel by thermal exposure to its outer wall.

Known technical solution according to Japanese patent No. 3653712, class. A47J 41/02, 1996 on the invention of "Portable thermos and method of its manufacture." The thermos contains an electric heater and heat-retaining material located inside the thermos, and is equipped with an electrical control circuit. The disadvantage of this device is the inability to change the temperature of the contents of the vessel by thermal exposure to its outer wall.

Known technical solution for Japanese patent No. 3207703, class. A47J 41/02, 1995 for the invention of “Metal thermos with double walls and thermostatic control”. The inner container of the metal thermos is made of ferromagnetic stainless steel. The outer tank is made of non-magnetic stainless steel. A vacuum is formed between the containers. The electric heating device is formed from a heating inductor of the solenoid type and from a high frequency current control circuit. A thermos is inserted inside the inductor. When a high-frequency current flows in the inductor, induction heating of the tanks occurs. The disadvantage of this device is the inability to change the temperature of the contents of the vessel by thermal exposure to its outer wall.

A technical solution according to German patent No. 04329138, cl. A47J 41/02, 1993 for the invention of "Thermos". Thermos consists of a container having double walls and a vacuum between them. Thermos is installed with its bottom on the heating plate. On one of the sections of the bottom of the thermos, the inner and outer walls are in contact, forming a heat-conducting bridge. Through this bridge, heat enters from the heating plate to the beverage in the thermos. The disadvantage of this device is the lack of thermal insulation of the bottom of the Dewar vessel.

Patent search did not reveal technical solutions that completely solve the problem.

The problem can be solved using the device shown in the drawing (in section). The device is a vessel (1) with double walls and a vacuum between them. An elastic container (2) (bellows, membrane box) with a coolant inside is attached to the bottom of the outer wall from the inside. A gap is formed between the elastic container and the inner wall of the vessel. To improve heat transfer, additional elements can be used in the device: tip (3) of an elastic container made of a material with high thermal conductivity, vessel wall (4), consisting of a combination of materials with different thermal conductivity. To improve the distribution of the coolant along the inner surface of the elastic container, a capillary-porous material (wick) can be used.

The device operates as follows. In the absence of heating of the outer wall and elastic capacity, the pressure that the coolant creates is small. Between the elastic tank and the inner wall of the vessel, a gap is maintained. There is no heat transfer between the outer and inner walls. When heating the outer wall and elastic capacity, the pressure of the coolant increases. The elastic container lengthens and contacts the inner wall of the vessel. Heat transfer occurs between the outer and inner walls. Depending on the amount of coolant in the elastic tank, heat transfer can be carried out by convection or by the principle of a heat pipe (US patent No. 3229759 from 02/02/1963).

Claims (4)

1. A vessel with double walls and a vacuum between them, characterized in that an elastic container with a heat carrier is fixed between the double walls, which has contact with one wall and the ability to contact with two walls in a heated state. 2. The vessel according to claim 1, characterized in that the final part of the elastic container with a coolant has a tip made of a material with high thermal conductivity. 3. The vessel according to claim 1, characterized in that the wall of the vessel consists of a combination of materials with different thermal conductivity. 4. The vessel according to claim 1, characterized in that the elastic container with a coolant contains capillary-porous material.

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