JPH0992451A - Method for bonding through high frequency induction heating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the thickness of a thermosetting adhesive at a predetermined value in bonding nonconducting members together through high frequency induction heating using the adhesive, so as to heat the adhesive uniformly and rapidly. SOLUTION: A thermosetting adhesive 2 and a high frequency induction heating element 4 on both sides of which are provided a number of projections 4a projecting in the direction of members 1, 3 to be laminated which are made from a nonconducting material, are interposed between the bonding surfaces of the members 1, 3 to be laminated, and the ends of the projections on the high frequency induction heating element are made to abut to the bonding surfaces of the members to be laminated. The heating element 4 may be provided with a through hole 4b. The projections on the heating element 4 which are buried in the thermosetting adhesive 2 keep the thickness of the thermosetting adhesive equal to their projected height (m).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for heat-bonding non-conductive members such as FRP, ceramics and wood by high frequency induction heating using a thermosetting adhesive.

[0002]

2. Description of the Related Art Non-conductive members such as FRP (fiber reinforced plastic), ceramics and wood are brought into contact with the adhesive surface of an adhered member coated with a thermosetting adhesive, and the adhered member is clamped with a clamp jig or the like. Was temporarily fixed, placed in an oven or the like, and heated to bond.

In Japanese Patent Laid-Open No. 4-5093, a cover member having a cover portion and a back portion, a magnetic plate mounted inside the back portion of the cover member, heated by electromagnetic induction heating, and having a large number of holes, A bookbinding member is described which is attached adjacent to a magnetic plate and includes a hot-melt adhesive that is melted by heat generated by the magnetic plate.

In JP-A-3-203931, a magnetic powder having a Curie point of 200 to 400 ° C. is mixed with a thermosetting resin, and the magnetic powder is heated by a high frequency magnetic field.
A curing method for curing a thermosetting resin by the generated heat is described.

In Japanese Patent Laid-Open No. 60-79082, an adhesive is formed on each of a pair of parts and an end surface is coated with an adhesive, and the end surfaces are butted parallel to each other. There is described a bonding structure of parts in which a space member having an outer diameter corresponding to the bonding thickness is interposed.

[0006]

In the conventional method of heating the thermosetting adhesive applied to the adherend using an oven to cure the adhesive, the adherent temporarily fixed with a jig or the like is used. Since it is necessary to put it in and out of the oven, workability is poor, and it may not be possible to perform total heating in the oven depending on the adherend. Further, it is difficult to make the thickness of the adhesive suitable for generating the maximum adhesive force.

In the one disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 4-5093, the magnetic plate having a large number of holes that generate heat is a flat plate, and the thickness of the molten adhesive cannot be appropriately maintained.
It is difficult to produce the best adhesion. Further, the one described in JP-A-3-203931 discloses a thermosetting resin in which a low melting point soluble metal piece sealed with a thermosetting resin is prevented from heat transfer melting and a magnetic powder is mixed. It is cured by heat and does not have a proper adhesive thickness. Further, in the one described in the above-mentioned JP-A-60-79082, a space member having an outer diameter corresponding to the required thickness of the adhesive is interposed, but in the case where heat is generated to promote and strengthen the adhesion. Absent.

According to the present invention, when a non-conductive member such as FRP, ceramics or wood is bonded by high frequency induction heating using a thermosetting adhesive, the adhesive can be kept at a predetermined thickness. Further, the present invention provides a high-frequency induction heating adhesive method in which the adhesive agent is uniformly and rapidly heated to obtain a maximum adhesive force in a short curing time.

[0009]

According to the present invention, when a non-conductive member is subjected to high-frequency induction heating adhesion using a thermosetting adhesive, the adhesive surface of an adherend member made of a non-conductive material is thermally cured. Adhesive and a high frequency induction heating element having a large number of projections projecting in the direction of the adherend on both sides are interposed, and the tips of the protrusions of the high frequency induction heating element abut the adhesion surface of the adherend. As described above, the high-frequency induction heating method is a heating and bonding method, and the high-frequency induction heating element may be provided with a through hole. The protrusion of the high frequency induction heating element embedded in the thermosetting adhesive keeps the thickness of the thermosetting adhesive equal to the protruding height.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a bonding process according to a first embodiment of the present invention. FIG. 1A shows a state in which a thermosetting adhesive 2 is applied to the adhesive surface of a non-conductive adherend member 1 such as FRP (fiber reinforced plastic), ceramics, or wood. FIG. 1B shows that the adhesive 2 is applied to the adhesive surface of the non-conductive adherend 3 and the conductive heating element 4 made of steel, iron or the like capable of high frequency induction heating is placed on the adhesive 2. 4 shows a state in which projections 4a projecting in both directions of the adherends 1 and 2 are provided on both sides and embedded in the adhesive 2 by a thickness m that maximizes the adhesive force. 4b is provided.

In FIG. 1C, both adherends 1 and 3 are set to the bonding position, and the tip of the projection 4a of the heating element 4 embedded in the adhesive 2 is
A state is shown in which the adhesive surfaces of the adherends 1 and 3 are in contact with each other and the adhesive is kept at a thickness m. As shown by the arrow, the hole 4b serves as a flow path between the adhesives on both sides, and plays a role of supplementing the excess and deficiency of the adhesive. The heating element 4 is caused to generate heat by the high-frequency induction heating coil 5, and the thermosetting adhesive is heated and adhered by heat transfer. At this time, the heating element 4 is located at the center of the adhesive 2, and the adhesive is heated uniformly and quickly.

FIG. 2 shows a second embodiment of the present invention in which two heating elements 4 similar to those shown in FIG. 1 are embedded in the adhesive between the adherends 1 and 3. The tips of the protrusions 4a of the heating element 4 contact the adhesive surfaces of the adherends 1 and 3 to keep the adhesive at a predetermined thickness m. Further, the thickness of the adhesive in the middle of the plurality of heating elements 4 is also m, and since both heating elements 4 are heated by the high frequency induction heating coil 5, the amount of heat generation is increased and the heating of the adhesive is accelerated to cure. The adhesive strength can be strengthened earlier. Hole 4b provided in heating element 4
Acts as an air escape hole to prevent voids in the adhesive, and also acts as a flow path for the adhesive to apply the adhesive to the adhesive surfaces of both adherends 1 and 3 even when the adhesive is applied on one side. Can be crossed.

[0013]

According to the present invention, when non-conductive members such as FRP, ceramics and wood are bonded by high frequency induction heating using a thermosetting adhesive, the thickness of the adhesive is kept at a predetermined value. Moreover, since the adhesive is heated uniformly and rapidly, the curing time is short and maximum adhesive force can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a process of adhesion according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Adhered member 2 Thermosetting adhesive 3 Adhered member 4 High frequency induction heating element 4a Protrusion 4b Through hole 5 High frequency induction heating coil

Claims (2)

[Claims] 1. A thermosetting adhesive and a high-frequency induction heating element having a large number of protrusions projecting toward the adhered member are provided on the adhesive surface of the adhered member made of a non-conductive material. A high-frequency induction heating bonding method, characterized in that high-frequency induction heating is carried out so that the tips of the protrusions of the high-frequency induction heating element come into contact with the bonding surface of the adherend member. 2. The high frequency induction heating bonding method according to claim 1, wherein a hole penetrating the high frequency induction heating element is provided.