JPH0440608Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial Application Field" This invention relates to a metal thermos flask that maintains excellent heat retention performance over a long period of time.

``Prior Art'' A metal thermos flask has an inner bottle and an outer bottle separated by a gap, and this gap is kept in a high vacuum to keep the inside warm.

In this metal thermos flask, as time passes, gas such as hydrogen gas is generated from the surfaces of the inner bottle and outer bottle, reducing the degree of vacuum in the cavity.
In order to prevent such a decrease in the degree of vacuum and to further improve the degree of vacuum, a getter for adsorbing gas is usually provided in the void. When the getter is provided in the cavity, the getter is held in the cavity by holding the getter with a holding fitting attached to the outer bottle.

``Problems that the invention seeks to solve'' However, when the getter is held with a holding metal fitting as described above, the manufacturing process of the thermos bottle becomes complicated, which increases the cost and also makes it less susceptible to shocks caused by vibration or dropping. As a result, there is a problem in that the getter is held in a loose state, causing the getter to move during use and producing an unpleasant sound. Also, in the unlikely event that Getztar
Or, if the holding metal fittings come into contact with the inner bottle, heat will be conducted between the inner bottle and the outer bottle through this contact area, reducing the heat retention performance of the thermos flask. In order to prevent this, it is necessary to provide a large space between the inner bottle and the outer bottle, which poses a problem in that the external dimensions of the thermos flask become larger.

This invention was made in view of the above-mentioned problems, and aims to provide a metal thermos flask in which the getter effect can be obtained without the need to hold the getter with a holding fitting or the like.

``Means to solve the problem'' This idea creates a double structure by joining an inner metal bottle and an outer bottle at the mouth, and creates a vacuum in the gap between the inner bottle and outer bottle. In the metal thermos flask,
Get at least part of the inner bottle and outer bottle mentioned above.
It is made of metal that has an effect.

"Embodiment" Hereinafter, a first embodiment of this invention will be described with reference to FIG.

In the metal thermos flask of this embodiment, the mouth of an inner bottle 1 made of titanium, which consists of a mouth and a body larger in diameter than the mouth, is connected to the outer bottle 2 made of titanium, which has a larger diameter than the inner bottle 1. The inner bottle 1 and the outer bottle 2 have a double structure by joining these mouth parts while being fitted into the mouth parts.
The gap 3 provided between the two is evacuated. The outer bottle 2 has a cylindrical outer bottle body 4 having a small-diameter opening at one end, and an outer bottle bottom 6 having an exhaust port 5 in the center joined to the large-diameter end of the outer bottle body 4 having a small-diameter opening at one end. A sealing plate 7 is joined from the outside to form a bottomed container shape.

Next, a method for manufacturing a metal thermos flask having such a configuration will be explained.

First, titanium material is formed into a bottomed container shape, and the inner bottle 1
At the same time, a cylindrical outer bottle body 4 is formed from a similar titanium material, and then the mouth of the inner bottle 1 is fitted into the mouth of the outer bottle body 4, and these mouths are welded. After joining, an outer bottle bottom 6 is formed at the open end of the outer bottle body 4. After this, the sealing plate 7 is supported so as to close the exhaust port 5 of the outer bottle bottom 6 from the outside with a gap, and in this state, the sealing plate 7 is placed in a vacuum heating furnace for heat treatment. While degassing the surface facing the cavity 3 and discharging this gas from the gap in the exhaust port 5, the sealing plate 7 and the outer bottle bottom 6 are joined by vacuum brazing to open the exhaust port 5. Vacuum seal. According to such a metal thermos,
Since all the members constituting the thermos flask are made of titanium, the entire surface facing the cavity 3 can exhibit the getter effect. Therefore, it is possible to improve the degree of vacuum in the cavity 3 and prevent a decrease in the degree of vacuum during use.Moreover, since titanium has low thermal conductivity, a thermos flask with extremely excellent heat retention performance is obtained. be able to. In addition, titanium is easy to work with,
Since it has excellent weldability, a thermos flask of a desired shape can be easily obtained, and the obtained thermos flask has excellent corrosion resistance, is lightweight, and has high strength.

FIG. 2 is a diagram showing a second embodiment of this invention.

In the metal thermos flask of this embodiment, the inner bottle 1, the outer bottle body 4, and the outer bottle bottom 6 are made of stainless steel,
Only the sealing plate 7 is made of titanium material. Therefore, it is the sealing plate 7 that exhibits the getter effect.
However, since inexpensive stainless steel is often used, manufacturing costs can be reduced.

FIG. 3 is a diagram showing a third embodiment of this invention.

In the metal thermos flask of this embodiment, the inner bottle 1 and the outer bottle body 4 are made of stainless steel, the outer bottle bottom 6 is made of titanium, and the outer bottle body 4 and the outer bottle bottom 6 are made of wax. It is joined by attaching etc. A chip tube 8 made of copper is connected to approximately the center of the outer bottle bottom 6 in a state that it is fitted into a hole formed in the outer bottle bottom 6. During vacuum heat treatment, this tip tube 8 discharges gas from the gap 3 from its tip, and the tip melts to seal the gap.

Although titanium was used as the getter in the metal thermos bottles in these Examples, other materials such as barium, zirconium, vanadium, cobalt, magnesium, germanium, niobium,
Metals having a getter effect such as tantalum and yttrium, or alloys thereof may be used as the getter.

"Effect of the invention" According to the metal thermos flask of this invention, at least a portion of the inner bottle and the outer bottle are made of getter, so that the getter effect can be achieved without separately providing a metal that has the getter effect. It is possible to improve the degree of vacuum in the gap and prevent the degree of vacuum from decreasing during use. Therefore,
Since there is no need for the retaining metal fittings used to hold the getter in conventional metal thermos flasks, the manufacturing process is simplified and costs can be reduced, and the getter is not held loose during use. No unpleasant noise is generated, and there is no need to increase the distance between the inner and outer bottles in order to provide holding fittings and getters, so metals with small external dimensions for a given capacity can be used. You can get a made thermos flask.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a first embodiment of this invention, and is a longitudinal sectional view of a metal thermos flask. FIG. 2 is a longitudinal sectional view of a metal thermos flask according to a second embodiment of this invention, and FIG. 3 is a longitudinal sectional view of a metal thermos flask according to a third embodiment of this invention. 1... Inner bottle, 2... Outer bottle, 3... Cavity.

Claims (1)

[Claims for Utility Model Registration] (1) A metal product made by joining an inner metal bottle and an outer bottle at the mouth to form a double structure, and creating a vacuum in the gap between the inner bottle and the outer bottle. 1. A metal thermos flask, characterized in that at least a portion of the inner bottle and the outer bottle are made of a metal having a getter effect. (2) A request for registration of a utility model characterized in that the metal having the getter effect is one metal or alloy selected from titanium, barium, zirconium, vanadium, cobalt, magnesium, germanium, niobium, tantalum, and yttrium. A metal thermos flask according to item 1.