JPH04277472A - Aluminum/other metal joining device - Google Patents

Abstract

PURPOSE:To offer an improved countermeasure for prevention of electrocorrosion at the joint part of a joining device for Al and other metal, which is applied to a heat emitting body device using positive characteristic thermister. CONSTITUTION:To join Al 1 with any other metal (terminal 2) to generate electrical connection, the joint part is covered with a consolidated two-layer type thermal shrinking tube 4, whose outer layer 5 is formed from a thermal shrinking resin having heat resistance and electrical insulativeness and inner layer 6 formed from a thermoplastic resin having heat resistance and an adhesiveness, and this tube 4 is contracted by heat to seal the joint part. This permits easy accomplishment of the sealing structure for shielding the joint part from the atmosphere. It is also easy to secure exterior protection having uniform thickness, and further this ensures excellent performance about environmental subjects, appearance quality, and working effectiveness.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a device for joining aluminum and dissimilar metals used in heating element devices using positive temperature coefficient thermistors, and in particular to measures to prevent galvanic corrosion at joints. It is.

0002

2. Description of the Related Art Hitherto, in a heating element device using a positive temperature coefficient thermistor, a structure has been adopted in which a fin made of aluminum and a terminal made of stainless steel are joined to establish electrical conduction. Examples of this are shown in FIGS. 4 and 5, where 1 is aluminum constituting the fins and the like, and 2 is a terminal made of stainless steel or the like. The terminal 2 has a dogleg-shaped cross section at the end where it joins the aluminum 1, and a plurality of burring protrusions 2a are provided on the doglegged end, sandwiching the end of the aluminum 1. By caulking the dogleg-shaped end, the burring protrusion 2a is attached to the aluminum 1.
Bonding and conduction are ensured by biting into the hole.

[0003] At the joint between the aluminum 1 and the terminal 2, which is a dissimilar metal, it is necessary to take measures to prevent electrolytic corrosion. Conventionally, as shown in FIGS.
Liquid paint 3 such as silicone paint was applied using simple equipment such as a brush to protect the joints.

0004

[Problems to be Solved by the Invention] When the above-mentioned joining device which has been subjected to galvanic corrosion prevention treatment is used in a heating element device that generates heat, the aluminum 1 and the terminal 2 which are different metals are Thermal stress occurs in the joint due to the difference in coefficient of thermal expansion. Therefore, the liquid paint 3 applied around the joint is required to be soft enough to withstand heat stress after hardening.

However, the above-mentioned silicone paints have the following problems. First, the liquid paint 3 has a disadvantage in that it requires large-scale ventilation equipment due to environmental concerns because it contains a solvent. In addition, quality problems such as sagging peculiar to liquid paints, variations in coating thickness due to uneven coating, and adhesion to other parts have been chronic, and the workability has been unfavorable.

Now, the function necessary for the above-mentioned galvanic corrosion prevention measures is to isolate the joint between the aluminum 1 and the terminal 2, which is a dissimilar metal, from the atmosphere, and a structure having a joint with external protection is used. is applied to various things, and the following items are typical of the requirements. These items include uniform thickness for exterior protection, elimination of adhesion to areas other than necessary, selection of materials that do not require solvents to improve the working environment, and exterior protection that can withstand thermal stress caused by heat at joints. The purpose is to ensure that

The object of the present invention is to provide an apparatus for joining aluminum and dissimilar metals, which is subjected to highly galvanic corrosion prevention treatment and solves these problems in terms of environmental friendliness, workability, and appearance.

[0008]

[Means for Solving the Problems] In order to solve this problem, the apparatus for joining aluminum and dissimilar metals of the present invention, when joining aluminum and other metals and making them electrically conductive, connects the joint to an outer layer. The inner layer is made of a heat-shrinkable resin with heat resistance and insulation properties, and the inner layer is a thermoplastic resin with heat resistance and adhesive properties.This heat-shrink tube is then heat-shrinkable. This makes the joint part a sealed structure.

[0009]

[Function] According to this structure, by using the integral two-layer heat shrink tube, the joint portion between aluminum and different metals can be shielded from the atmosphere, and a sealed structure can be easily achieved. In addition, it ensures a uniform thickness of exterior protection, has no environmental problems unlike liquid paints, and has the advantage of being excellent in appearance quality and workability.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a top view of the bonding device of the present invention, FIG. 2 is a side view of the same, and FIG. 3 is an integrated type 2 used in the device.
It is a perspective view showing a layered heat shrinkable tube, and the same numbers are attached to the same parts as in the conventional example.

In FIGS. 1 to 3, the aluminum 1 and the terminal 2 are joined together by caulking the doglegged ends of the terminal 2 sandwiching the ends of the aluminum 1, as described above. A plurality of burring protrusions 2a provided at the ends bite into the aluminum 1 to ensure bonding and electrical continuity. In this state, the joint portion is exposed to the atmosphere. Next, an integrated two-layer heat-shrinkable tube 4 as shown in FIG. 3 is inserted into the joint, heat is applied to the tube 4 to shrink the joint, and the joint is heat-shrinked as shown in FIGS. 1 and 2. It has a structure that is sealed with a tube 4.

[0012] In the integrated two-layer heat shrinkable tube 4, the outer layer 5 is made of a heat-shrinkable resin having heat resistance and insulation properties, and the inner layer 6 is made of a thermoplastic resin having heat resistance and adhesive properties. For example, Sumitube manufactured by Sumitomo Electric Industries, Ltd. is known. As mentioned above, FIGS. 1 and 2 show a state in which the tube 4 is heated and shrunk, and the outer layer 5 is shrunk along the caulked portion, and the inner layer 6 is thermoplastic, so the outer layer 5 is This indicates that more protrusion occurs. This shows that the sealing required to prevent galvanic corrosion is ensured to isolate the joints from the atmosphere.

In the above embodiment, the integral two-layer heat shrink tube 4 not only has excellent heat resistance and insulation properties, but also has an outer layer 5 that is soft and has strong physical properties, so it is resistant to heat stress. also shows stable performance. Further, the thermoplastic resin of the inner layer 6 is bonded so as to firmly cover the joint between the aluminum 1 and the terminal 2, which is a dissimilar metal. From this, it becomes possible to reliably isolate the joint portion between the aluminum 1 and the terminal 2, which is a dissimilar metal, from the atmosphere, which is considered important in measures to prevent electrolytic corrosion. Tube 4 also eliminates work environment problems caused by solvents, which have been a problem in the past.
It also solves environmental concerns since it does not contain solvents. Furthermore, unlike liquid paints in terms of workability and appearance quality, it is possible to easily and uniformly protect the exterior.

[0014]

[Effects of the Invention] As described above, according to the present invention, the integrated type 2
By using layered heat shrink tubing, it is possible to easily isolate the joint between aluminum and dissimilar metals from the atmosphere and create a hermetically sealed structure. Therefore, measures to prevent galvanic corrosion are required in this type of joint structure. It is highly anticipated that it will be applied to a variety of products. In addition, by using an integrated two-layer heat shrink tube, it is easy to ensure a uniform thickness of exterior protection, and unlike liquid paints, there are no environmental problems, and it also has excellent appearance quality and workability. You can get the effect of Furthermore, the mechanical strength is naturally superior compared to liquid paints.

[Brief explanation of the drawing]

FIG. 1 is a top view showing an embodiment of a joining device according to the present invention.

[Fig. 2] Side view of a joining device in one embodiment

[Fig. 3] A perspective view of an integrated two-layer heat shrink tube used in one embodiment.

[Fig. 4] Top view of a conventional joining device

[Fig. 5] Side view of a conventional joining device

[Fig. 6] Top view of a conventional joining device that has been treated to prevent electrolytic corrosion.

[Fig. 7] Side view of the joining device shown in Fig. 6.

[Explanation of symbols]

1 Aluminum 2 Terminals made of different metals 2a Burring protrusion 4. Integrated double-layer heat shrink tube 5 Outer layer 6 Inner layer

Claims (1)

[Claims] [Claim 1] When joining aluminum and other metals and making them conductive, the joint is made of a heat-shrinkable resin whose outer layer has heat resistance and insulation properties, and whose inner layer has heat resistance and adhesive properties. A device for joining aluminum and dissimilar metals that is coated with an integrated two-layer shrinkable tube made of thermoplastic resin, and the heat-shrinkable tube is heat-shrinked to create a sealed structure at the joint.