JPS63189228A - Method for joining various joining members through resistance heating - Google Patents

Abstract

PURPOSE:To eliminate or facilitate the finishing work and make it possible to execute on-site worping by a method wherein the joining is done by melting an electrically conductive thermoplastic synthetic resin film, which is pinched between joints, by the Joule heat generated by energizing the film. CONSTITUTION:As a thermoplastic synthetic resin, polyvinyl chloride synthetic resin, acrylonitrile-butadiene-styrene synthetic resin, polystyrene synthetic resin, polycarbonate synthetic resin or the like is exampled. When joining members 1 are of thermoplastic synthetic resin material, an electrically conductive synthetic resin film 2, which is same in kind and has compatibility with the joining member, is preferably used from the view point of easiness of welding and enhancement of bonding strength. In addition, by energizing the film 2, the Joule heat is generated, resulting in melting of the film itself by the heat. When the film is of polyvinyl chloride synthetic resin-based one, for example, the film is heated up to the melting point of the film of about 150-200 deg.C through the energizing of the film.

Description

[Detailed Description of the Invention] Industrial Field of Application This invention relates to the joining of joining members of various materials and shapes, such as the joining of members constituting a picture frame, especially the joining of synthetic resin materials. The present invention relates to a joining method suitably employed for joining.

Conventional technology and its problems Conventionally, for example, when joining components of a picture frame made of hard synthetic resin, the surfaces of the components to be joined are first heated and melted using a heater, and then these joining surfaces are immediately bonded. A method of fusion fixing is adopted by butting the buttocks together. In such a method, the two members are compatible with each other and a strong bonding strength can be obtained.

However, so-called burrs tend to occur around the joints, which impairs the appearance of the joint, requiring a troublesome finishing process to remove the burrs, and also has the disadvantage of poor processing accuracy.

Still other methods include high-frequency welding, which utilizes heat generated by molecular motion in a high-frequency electric field, ultrasonic welding, which utilizes frictional heat generated by ultrasonic vibration, and even welding that uses heat sprayed from a hot air welding machine. Various welding methods such as hot air welding, which involves melting using a hot air stream such as heated air, are sometimes used, but all of these methods require large or special equipment, which is difficult to do at construction sites, for example. The problem was that it could not be adopted.

On the other hand, instead of the above-mentioned joining methods, methods of joining using adhesives have been widely adopted, but compared to the above-mentioned joining methods, sufficient joining strength cannot be obtained, or the material In some cases, there is a problem in that suitable adhesives do not exist.

This invention was made to solve the above-mentioned problems, and can be used to join joining members made of various materials and shapes, and can eliminate or easily perform finishing processing. Furthermore, the present invention attempts to present a method for joining joining members that can be constructed on-site without requiring any special equipment or the like.

Means for Solving the Problems For the above purpose, the inventor has conducted various experiments and research, and has found that by applying electricity to a conductive thermoplastic synthetic resin film, it generates Joule heat, and this heat causes the film to They focused on the fact that the synthetic resin melts, and that this melted synthetic resin acts as an adhesive, leading to the completion of this invention.

That is, in the bonding method according to the present invention, when bonding members made of various materials and shapes are bonded, a conductive thermoplastic synthetic resin film is sandwiched between these bonded parts, and then the film is The film is characterized in that the above film is melted and bonded by the Joule heat generated by energizing it.

The wave joining member to which the joining method according to the present invention is applied is not particularly limited in terms of material, shape, etc.

However, as for the material, it is desirable to use a thermoplastic synthetic resin material that is compatible with the conductive thermoplastic synthetic resin film described below, from the viewpoint of ease of bonding or improvement of bonding strength, but this is not necessarily the case. It is not limited. Other materials such as wood or metal may also be used, and the material may be any combination of joining members of different types as well as combinations of joining members of the same type.

In addition, various shapes such as rod-shaped bodies and plate-shaped bodies are permitted, and various joining forms such as butt joints, overlapping joints, and full or partial joints are also permitted. sell.

Examples of the thermoplastic synthetic resin include polyvinyl chloride synthetic resin (PVC), acrylonitrile-butadiene-styrene synthetic resin (ABS), polystyrene synthetic resin (PS), polycarbo, and nate synthetic resin (PC). .

On the other hand, the film used to join these joining members is a conductive thermoplastic synthetic resin film, and when electricity is applied to it, Joule heat is generated, and the film itself is damaged by the heat. It needs to be something that can be melted.

Examples of such films include polyvinyl chloride synthetic resin (PVC), acrylonitrile butadiene styrene synthetic resin (ABS), and polystyrene synthetic resin (PS).
, a base film made of polycarbonate synthetic resin (PC) or the like with thin nichrome wires embedded over substantially the entire surface thereof can be used. However, instead of this nichrome wire, a patterned heater wire circuit may be provided in the base film as described above. Furthermore, heat Eji as mentioned above! Carbon (C), tin oxide (SnO2),
It may also have conductivity by kneading a conductive substance such as silver (Ag) or copper (CU).

When the bonding member is a thermoplastic synthetic resin material, it is desirable to use a conductive synthetic resin film having the same type of compatibility from the viewpoint of ease of bonding or improvement of bonding strength.

In addition, the thickness of the film needs to be as thin as possible in order to improve processing accuracy, but it must be as thin as possible in order to obtain the bonding strength suitable for the application of the bonded member. It goes without saying that it is necessary to take this into consideration. Usually the thickness is 0, 3~0. About 1rtm, preferably 0
．． Those with a length of 5m+ or less are used.

For example, if the film is based on vinyl chloride synthetic resin, the upper 4a film may be heated to about 150 to 200°C, which is the melting point of the film. In short, as long as the film satisfies the conditions for melting and hanging due to the Joule heat generated by it, there are no restrictions on the type of power source, whether direct current or alternating current, and on the applied voltage, energization time, etc. It's not a thing.

By the way, when the bonding members are two thermoplastic synthetic resin materials, the bonded portions thereof are melted together with the film and are integrally bonded. On the other hand, when the bonding member is other than the above, the resin of the melted film acts as an adhesive.

Further, it goes without saying that it is desirable to apply a predetermined pressure when temporarily fixing the joining member.

Furthermore, although the size of the film that corresponds to the joining surface of the joining member is generally used, a film that is larger or smaller than this may be used depending on the case. Even if a large film is used, since the film is thin, the finishing work of removing the protruding parts around it is easy. In addition, when using a small one, it is necessary to lead the electrode terminal to the outside.

Effects of the Invention The resistance heating bonding method for various bonding members according to the present invention has no effect on the bonding strength when the bonding members are made of thermoplastic synthetic resin compared to the conventional fusion fixing method. Not only is it comparable, so-called flaking is less likely to occur around the joints, making finishing processing unnecessary or easy. Furthermore, it is possible to bond even synthetic resin materials for which no suitable adhesive exists, such as fluorocarbon resin materials.

Furthermore, since joining can be performed as long as there is a power source, there is no need for large or special equipment such as those used in high-frequency welding methods, and it is not only possible to perform on-site construction, but also to make it possible to connect materials, shapes, joining methods, etc. It can be adopted almost independently.

Example Next, the present invention will be described with reference to embodiments.

As shown in Figure 1, a band-shaped sheet member (1) made of vinyl chloride synthetic resin with a thickness of 1 ml and a width of 10 m
).

The synthetic resin film (2) used to join these members (1) and (1) is made of vinyl chloride synthetic resin, has a thickness of 0.5 #ls+, and has a size of 10 mm x 50 mm inside the base film (3). 60μm nichrome wire (4
) were installed in parallel at each standard interval, and these were connected in parallel and buried. The interelectrode resistance value of this film was approximately 200Ω.

Then, as shown in FIGS. 2 and 3, the ends of the band-shaped sheet members (1) and (1) are overlapped with each other over a length of 50 m, and the conductive material is placed between them. sandwiching a thermoplastic synthetic resin film (2) having
And a weight (W) was placed on top of it to temporarily fix it.

Thereafter, electricity was applied to the film (2).

Here, the energization conditions were as follows.

Applied voltage = 60 V Frequency: 60 Hz Current application time: 1 minute Then, after the above-mentioned current application, it was left as it was for a while to allow it to cool naturally.

In the thus obtained bonded product, the film (2) was melted by the Joule heat generated during energization, and was in a state in which it was compatible with the sheet members (1) and (1).

As a precaution, we conducted a tensile strength test to check the joint strength, and found that the material broke at a location other than the joint.

In addition, in order to compare the present invention with the conventional method, when sheet members exactly similar to those in the above embodiment were heated and welded together, not only did the heating take a long time, but also the sheet members was deformed by the load, making it impossible to perform the intended joining.

From this result, it was confirmed that the method according to the present invention enables accurate and reliable joining.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is an overall perspective view of a band-shaped sheet member that is a joining member and a conductive thermoplastic synthetic resin film, and FIG. 2 is an explanation showing the state at the time of joining. FIG. 3 is a sectional view taken along the line ■-■ in FIG. 2. (1)...Joining member (band-shaped sheet member), (2)...
・Thermoplastic synthetic resin film that is conductive. Amendment to the above procedure March 10, 1988 Patent Application No. 23088 2 Title of the invention Resistance heating joining method for various joining members 3 Relationship with the person making the amendment Patent applicant Address Hirano, Osaka City 2-3-9 Hirano Kita Ward Name: Eitai Kako Co., Ltd. Representative Kiyomitsu Wada 4 Agent address: 72-45 Unagidani Nakano-cho, Minami-ku, Osaka City Date of amendment order (voluntary amendment) 6. Increased due to amendment Number of inventions to be amended: 17, Detailed explanation of the invention column 8 of the specification to be amended, Contents of the amendment (1) "Weight" in the seventh line from the bottom of page 11 of the specification is corrected to "load". that's all

Claims (5)

[Claims] (1) When bonding members made of various materials and shapes are bonded, a conductive thermoplastic synthetic resin film is sandwiched between these joints, and then electricity is applied to the film. A resistance heating joining method for various joining members, characterized in that the film is melted and joined using Joule heat. (2) A resistance heating bonding method for various bonding members according to claim 1, wherein the conductive thermoplastic synthetic resin film is formed by embedding a heater wire in a base film made of a thermoplastic synthetic resin. . (3) The electrically conductive thermoplastic synthetic resin film is obtained by kneading a conductive substance such as carbon or tin oxide into a thermoplastic synthetic resin. Heat bonding method. (4) A method for resistance heating joining various joining members according to claim 2 or 3, wherein the thermoplastic synthetic resin is a vinyl chloride synthetic resin. (5) A resistance heating joining method for various joining members according to claim 2 or 3, wherein the thermoplastic synthetic resin is a polystyrene synthetic resin.