JPH0429372B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for joining the mouth of a double-breasted metal bottle, such as a metal thermos flask consisting of an inner cylinder and an outer cylinder, whose mouth requires anti-corrosion treatment.

Metal thermos flasks, which are made up of a metal inner cylinder and an outer cylinder, are widely used as portable thermos flasks because of their excellent impact resistance. The inner and outer cylinders of this type of metal thermos were traditionally made of highly corrosion-resistant stainless steel, but in recent years,
By using carbon steel or the like for the outer cylinder, the material cost of the thermos flask is reduced. however,
Carbon steel is a material with inferior corrosion resistance compared to stainless steel, and since the mouth of a thermos comes into contact with the contents when pouring or dispensing the contents, such as hot water or water, the mouth of the outer cylinder has poor corrosion resistance. It is also necessary to apply anti-corrosion treatment to the joints of the mouths of the inner and outer cylinders where dissimilar metals come into contact.

Therefore, as shown in Fig. 1, the opening of a conventional metal thermos flask is connected to an edge 2a on the opening side of the opening 2 of the inner cylinder 1 (hereinafter referred to as the opening edge) and an outer edge 2a of the opening 2 of the inner cylinder 1. After the openings 2 and 4 are joined and integrated with the opening edge 4a of the opening 4 of the cylinder 3 aligned and aligned,
This has been done by applying anti-corrosion treatment such as plating or painting to the opening 4 of the outer cylinder 3.

By the way, if the spout is joined using this method by aligning the inner and outer cylinder ends of the spout, molten metal and brazing filler metal will flow to the inner cylinder wall, staining the wall surface, and forming unevenness, causing the plug body to deteriorate. Not only will the alignment become poor, but the anti-corrosion treatment will also apply to the inner surface of the mouth 2 of the inner cylinder 1, which is unnecessary, and a part of the inner surface will be plated or have anti-corrosion paint adhered to it. There was an inconvenience. Moreover, since the inner surface of the mouth part 2 of the inner cylinder 1 is surrounded, it is difficult to uniformly apply anti-corrosion treatment, which tends to result in deterioration in aesthetic appearance and gives rise to problems such as giving an unfavorable impression to customers. Ta.

Therefore, the opening of the mouth 2 of the inner cylinder 1 is closed with a masking jig such as a rubber stopper to prevent the molten metal from flowing onto the inner cylinder wall surface and to prevent corrosion from reaching the inner surface of the mouth 2 of the inner cylinder 1. Things are being done in such a way that it is not necessary to do so. However, when such a masking jig is used, a shadow area is created by the masking jig, and the outer cylinder 2
There was a problem in that it was difficult to apply anti-corrosion treatment to the outer surface of the mouth portion 4, particularly to the open end surface 4a of the mouth portion 4 and the externally exposed portion 5a of the joint portion 5 of the inner and outer cylinders 1 and 2.

This invention was made in view of the above-mentioned circumstances, and prevents excess molten metal from flowing down and unnecessary anti-corrosion treatment such as anti-corrosion paint or plating on the inner surface of the mouth portion 2 of the inner cylinder 1. Completely welded on outer cylinder 2
The object of the present invention is to provide a method for joining the mouth of a metal thermos flask, which can be joined and subjected to anti-corrosion treatment.

Hereinafter, a method for joining the mouth of a metal thermos flask according to the present invention will be explained.

FIG. 2 is an enlarged view of the mouth of a metal thermos flask for explaining one embodiment of the method of the present invention.
The reference numeral 11 in the figure is an inner cylinder, and this inner cylinder 11 is made of a highly corrosion-resistant metal such as stainless steel.
It is designed to prevent corrosion by hot water, cold water, etc. poured into the inner cylinder 11. Reference numeral 12 denotes an outer cylinder, and the outer cylinder 12 is made of a metal such as carbon steel, which has slightly lower corrosion resistance than stainless steel. Further, the inner diameter of the opening 13 of the outer cylinder 12 is formed to be approximately equal to the outer diameter of the opening 14 of the inner cylinder 11.

In the mouth joining method of the present invention, first, the positions of the mouth 14 of the inner cylinder 11 and the mouth 13 of the outer cylinder 12 are adjusted such that the opening side end 15 of the mouth 14 of the inner cylinder 11 is the same as that of the outer cylinder. 12 so as to protrude from the opening edge 16 of the opening 13 by a predetermined distance.

Next, the inner and outer cylinders 1 aligned as described above
The openings 13 and 14 of Nos. 1 and 12 are hermetically joined together by welding methods such as brazing, seam welding, and Teig welding. Furthermore, since the mouth portion 14 of the outer cylinder 12 is joined onto the outer wall surface of the inner cylinder 11, weld metal and brazing metal can be prevented from flowing down onto the inner wall surface of the inner cylinder 11.

After the mouth parts 13 and 14 are joined and integrated in this manner, the mouth part of the thermos bottle is subjected to anti-corrosion treatment. Anti-corrosion treatment is
At least the outer peripheral surface of the mouth 13 of the outer cylinder 12, the opening edge 16, and the joint 17 between the inner and outer cylinders 11 and 12.
Externally exposed portion 17a exposed to the outside (the above portion is hereinafter referred to as the main portion 19 and is indicated by a dotted line in FIG. 2).
give to Also, during this anti-corrosion treatment, the inner cylinder 11
If necessary, the opening of the mouth part 14 of the inner cylinder 11 is closed with a masking jig such as a rubber stopper 18 as shown by the dashed line in FIG. 2 so that the inner surface of the mouth part 14 is not subjected to corrosion protection.

The anti-corrosion treatment methods used at this time include coating the main parts 19 with plating with metals or alloys such as nickel (N1) and chromium (Cr), which have higher corrosion resistance than carbon steel, or coating the main parts 19 with powdered synthetic resin. A method of covering the main part 19 by welding, pouring, etc., a method of covering the main part 19 by painting,
A chemical conversion coating method is performed in which the metal surface of the main part 19 is chemically converted to create a so-called corrosion product, and the main part 19 is covered with this product.

In such a mouth joining method, the inner cylinder 11
and the outer cylinder 12 are aligned so that the opening side end 15 of the opening 14 of the inner cylinder 11 protrudes from the opening edge 16 of the outer cylinder 12, and then these openings 13 and 14 are joined and integrated. Therefore, even if the mouth 14 of the inner cylinder 11 is closed with a masking jig such as the rubber stopper 18 to prevent the formation of an anticorrosive layer on the inner surface of the mouth 14 of the inner cylinder 11, the open end of the outer cylinder 12 Edge 16 and joint 17
The externally exposed parts 17a and other parts of the masking jig do not cast shadows on the main parts 19 that require anti-corrosion treatment.
can be completely anti-corrosion treated. Therefore, according to this mouth part joining method, there is no possibility that anti-corrosion areas will be formed in patches on the inner surface of the mouth part 14.
Moreover, since the main part 19 can be completely anti-corrosion treated, it is possible to obtain a metal thermos flask with excellent corrosion resistance and a clean appearance.

In addition, in such a mouth joining method, when joining the mouth 14 of the inner cylinder 11 and the mouth 13 of the outer cylinder 12 by brazing, the opening side end 15 of the inner cylinder 11 protrudes. Therefore, this serves as a protection, thereby preventing the molten brazing material from flowing into the inner surface of the mouth 14 of the inner cylinder 11. Therefore, it is not necessary to perform the work of removing the wax material that has flowed in afterwards, so that the finish of the inner surface of the mouth part 14 of the inner cylinder 11 is improved, and a clean metal thermos flask can be easily manufactured.

Furthermore, in such a brazing method, due to the difference in wettability of molten brazing material between stainless steel and carbon steel, molten brazing material is used in the outer cylinder 1 made of carbon steel.
The liquid flows to the first side and covers the opening edge 16 of the mouth 13 of the outer cylinder 12 and the outer peripheral surface. Therefore, if silver solder, nickel solder, etc., which have excellent corrosion resistance are used as the soldering material, there is no need to perform anticorrosion treatment on the part of the mouth 13 of the outer cylinder 12 that is covered with such soldering material. It's a good idea to do it within a narrow range. Moreover, since the distance from the open end 20 of the inner cylinder 11 to the part requiring anti-corrosion treatment becomes large, in some cases, the rubber plug 18 may be used to prevent anti-corrosion treatment from being applied to the inner surface of the mouth 14 of the inner cylinder 11. Therefore, it becomes unnecessary to close the mouth portion 14 of the inner cylinder 11, and therefore anticorrosion treatment can be performed more easily.

In the above embodiments, the inner cylinder 11 is made of a highly corrosion-resistant metal material and the outer cylinder 12 is made of a material with poor corrosion resistance. However, the present invention is not limited to this, and any It goes without saying that this method can also be applied to the case where metal materials are joined and integrated, and similar effects can be achieved.

As explained above, the method for joining the mouth of a double metal bottle of the present invention is to connect the opening side end of the mouth of the inner cylinder to
After aligning the outer cylinder so that it protrudes beyond the opening edge, the openings are joined together and then anti-corrosion treatment is applied to the opening of the outer cylinder, so there is no molten metal flowing down the inner wall of the inner cylinder. Furthermore, it is possible to easily prevent unnecessary anti-corrosion treatment from being applied to the inner surface of the mouth of the inner cylinder, and
Since the masking jig used for this process does not shade the areas that require anti-corrosion treatment, complete anti-corrosion treatment can be applied to the necessary areas. Therefore, this mouth joining method provides excellent corrosion resistance and A clean metal thermos flask can be manufactured. This effect is particularly great when a metal thermos flask is made in which the inner cylinder is made of a corrosion-resistant metal material and the outer cylinder is made of a metal material with poor corrosion resistance.

[Brief explanation of drawings]

FIG. 1 is a partially sectional plan view for explaining a conventional mouth joining method, and FIG. 2 is a partially sectional plan view for explaining the mouth joining method of the present invention. DESCRIPTION OF SYMBOLS 11... Inner cylinder, 12... Outer cylinder, 13... Mouth part (outer cylinder), 14... Mouth part (inner cylinder), 15... Opening side end, 16... Opening edge.

Claims (1)

[Scope of Claims] 1. When manufacturing a metal vacuum double-bottle bottle in which the space between the inner and outer cylinders is evacuated, when the inner and outer cylinders are joined together, the opening side end of the mouth of the inner cylinder is connected to the outer cylinder. A method of joining a mouth of a double metal bottle, characterized in that after aligning the mouth so that it protrudes beyond the edge of the mouth opening, these mouths are joined and integrated, and then anti-corrosion treatment is applied to the mouth of the outer cylinder. Method. 2. A method for joining a mouth portion of a metal double bottle according to claim 1, characterized in that the inner cylinder is made of a metal material with high corrosion resistance, and the outer cylinder is made of a metal material with poor corrosion resistance.