JPH1128526A - Method for bonding hemmed panel and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding device for hemmed panels for heating thermosetting adhesive for joining between the inner and outer panels of the hemmed panels without generating thermal stress. SOLUTION: An electrically insulating block 10 is provided in the same plane shape as the upside of a lower die 1 in a region facing to the flange part of the outer panel of the die 1 and also a pair of electrodes 11, 12 for supplying current are embeded in the same plane shape as the upside of the block 10 in both end parts in the direction along the flange parts of this block. In a state where the hemmed panels are pressurized with a bending blade, Joule heat is generated corresponding to the resistance and the amount of current in a current route between both end parts of the flange part and its neighborhood is heated by heat transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of heating and curing a thermosetting adhesive interposed between two panels when the outer panel flange is folded and hemming is performed so as to sandwich the inner panel flange. TECHNICAL FIELD The present invention relates to a method and an apparatus for bonding a hemmed panel for bonding.

[0002]

2. Description of the Related Art Conventionally, such a bonding is performed by setting a heating device which generates a hot air or a magnetic field for induction heating as a separate process after the hemming process is completed, and heating the flange portion. Was.

[0003]

Therefore, it is necessary to separately provide dedicated equipment, and there is another problem that the shape of the flange portion is distorted during heating.

In view of the foregoing, the present invention provides a method for bonding a hemmed panel for heating a thermosetting adhesive for bonding between an inner panel and an outer panel of a hemmed panel without generating thermal distortion. And an apparatus.

[0005]

In order to achieve the above object, according to the present invention, there is provided a hemmed panel in which a flange portion of an inner panel is hemmed so as to be sandwiched between folded flange portions of an outer panel. In a method of bonding a hemmed panel for heating and bonding a thermosetting adhesive interposed therebetween, a flange portion of an inner panel is bonded to a flange portion of an outer panel placed on a lower mold. With the agent interposed, the bending blade is lowered for hemming, the pre-bent part of the outer panel flange is further folded back and pressurized between the lower molds, and the pressurization with the bending blade lowered is continued. In this state, current flows between both ends in the direction along the flange portion of the inner panel or outer panel flange portion, causing Joule heat. The Chakuzai is thermally cured, it is characterized by increasing the bending blade after thermal curing. In a state where the hemmed panel is pressed by the bending blade, Joule heat is generated according to the resistance and the current amount of the current path between both end portions of the flange portion, and the vicinity thereof is also heated by heat propagation.

In order to carry out the bonding method according to the first aspect with a bulky structure, according to the second aspect, an insulating block is provided in a region facing the flange portion of the outer panel in the mold so as to be flush with the upper surface of the lower mold. At the same time, a pair of electrodes for supplying current are buried at both ends in the direction along the flange portion of the insulating block in the same plane as the upper surface of the insulating block.

At this time, in order to simultaneously supply current to the press hemming machine body in an insulated state, the entire upper end portion of the lower mold is replaced with an electrically insulating block and a flange portion of the block is formed. It is conceivable to embed a pair of electrodes for supplying current in the same plane as the upper surface of the block at both end portions in the direction along.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bonding apparatus for carrying out a method for bonding a hemmed panel according to the present invention will be described with reference to FIGS. The bending blade 5 as an upper die facing the lower die 1 is driven to move up and down so as to sandwich the flange portion 31 of the inner panel 3 by folding the flange portion 21 of the outer panel 2 like a normal press hemming machine. ing.

According to the present invention, a portion of the lower die 1 shifted from the portion corresponding to the bending blade 5 toward the work is cut out in a rectangular shape along the flange portions 21 and 31 and, for example, M
An electrically insulating block 10 made of a hard synthetic resin such as C nylon is mounted on the same surface as the upper surface 1a of the lower die 1. In this block, a pair of electrodes 11 and 12 are provided near the upper end 11 near both ends in the direction along the flange portion 21.
a and 12a are embedded in the same plane as the block upper surface 10a. Conductive wires 13 and 14 are led out from the bottom surfaces of these electrodes, and are connected to a power supply that supplies a large current intermittently, for example, like a welding power supply. For example, MC nylon (trade name of engineering plastic) is used for the lower mold 1 and the bending blade 5.
Or plate-shaped electrical insulation materials 17 and 18 made of bakelite
Is interpolated.

The operation of the bonding apparatus configured as described above will be described with reference to FIG. Flange part 2 of outer panel 2
The thermosetting adhesive 19 is applied to the adhesive portion of the lower panel 1 and placed on the lower mold 1, and the flange portion 31 of the inner panel 3 is overlaid thereon. The preliminary bending blade 9 is moved in the horizontal direction, and the preliminary bending portion 21a at the distal end of the flange portion 21 is preliminarily bent from the position shown by the dotted line to the solid line position (A in the figure).

In order to press the pre-bent portion 21a between the lower molds 1 and fold it back to sandwich the flange portion 31, the pre-bending blade 9
Is retracted, and the bending blade 5 is lowered (FIG. B).

When a current is supplied to the electrodes 11 and 12 for a predetermined time while the pressurizing operation for finishing the hemming process is continued by lowering the bending blade 5, the block 10 electrically insulates the lower mold 1. In this state, an amount of current corresponding to the resistance flows through a current path between the portions of the flange portion 21 that come into contact with these electrodes, and a corresponding Joule heat is generated and propagated to the vicinity. For example, 1,500 A is intermittently flowed tens of times for one minute. The current path is the overlapping flange 31
Also, it is formed in accordance with the contact resistance, and corresponding heat is generated and propagated to the vicinity.

As a result, the material of the block 10 also exhibits a thermal insulating action, so that the adhesive 19 is efficiently cured by heat without escaping heat to the lower mold 1. During this time,
Since the flange portions 21 and 31 are pressurized while the pre-bent portion 21a is folded and the flange portion 31 is sandwiched, the surface shape is not deformed. Further, the lower die 1 and the tip of the bending blade 5 are insulated from the press hemming machine main body at the earth potential by the electric insulating materials 17 and 18 so that sparking or current sneaking when energized is avoided. You. After a lapse of a predetermined time required for thermosetting, the bending blade 5 is raised.

FIG. 3 shows a bonding apparatus according to another embodiment of the present invention, in which the entire area of the tip portion of a lower die 31 made of cast iron is replaced with a rectangular heat / electrically insulating hard synthetic resin block 33. At the same time, a pair of electrodes 34 is embedded in the same plane at both ends in the direction along the flange portion. Bending blade 5
Also, an insulating material 37 is interposed therebetween. Thereby, in order for the block 33 to have an insulating function for the entire lower die 1,
There is no need to separately provide an electrical insulating material.

Further, an apparatus for implementing the bonding method according to the present invention is such that a pair of electrodes are automatically moved from a separated position to a contact position with respect to a flange portion of an inner or outer panel in a pressurized state so that a current flows. It is also conceivable to configure it.

[0016]

According to the first aspect of the present invention, it is not necessary to prepare a heating facility at another place in order to cure the adhesive in the pressurized state of the press hemming machine. Also,
By heating the thermosetting in a state in which the flange portion of the work is pressed, thermal distortion does not occur and the shape accuracy of the work is ensured.

According to the second aspect of the present invention, by embedding the current supply electrode in the lower mold, the heating device has a bulky structure, which is advantageous in equipment cost. The shape accuracy of the work is ensured because the adhesive is thermally cured in a pressurized state. According to the third aspect of the present invention, since the entire upper end portion of the lower mold is formed of the electrically insulating block, the block itself can be electrically insulated from the press hemming machine main body.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of an apparatus for bonding a hemmed panel according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating an operation of the bonding apparatus.

FIG. 3 is a sectional view of a main part of a bonding apparatus according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower mold 2 Outer panel 3 Inner panel 5 Bending blade 10 Block 11, 12 Electrode 21, 31 Flange part

Claims (3)

[Claims] 1. A hemming panel for heating and bonding a thermosetting adhesive interposed between hemmed panels that are hemmed so that a flange portion of an inner panel is sandwiched between folded flange portions of an outer panel. In the bonding method, the flange portion of the inner panel is overlapped with the flange portion of the outer panel placed on the lower die with a thermosetting adhesive interposed therebetween, and the bending blade is lowered for hemming to lower the outer panel. The pre-bent portion of the flange portion is further folded back and pressurized between the lower dies, and in a state where the pressurization with the bending blade lowered is continued, the flange in the flange portion of the inner panel or the outer panel. The adhesive is thermoset by Joule heat by passing a current between both ends in the direction along the The bending method of bonding hemming panels, characterized in that raising the blade. 2. A thermosetting adhesive which is interposed between both panels is heated on a hemmed panel manufactured by hemming a flange portion of an inner panel by folding a flange portion of an outer panel. In a bonding apparatus for a hemmed panel for bonding by bonding, an electrically insulating block is provided in a region facing the flange portion of the outer panel in the lower die so as to be flush with the upper surface of the lower die. A bonding apparatus for a hemmed panel, wherein a pair of electrodes for supplying current are embedded in both ends in the direction along the same plane as the upper surface of the block. 3. A hemmed panel for heating and bonding a thermosetting adhesive interposed between hemmed panels hemmed so as to sandwich the flange of the inner panel between the folded flanges of the outer panel. In the bonding method, the entire upper end portion of the lower mold is replaced with an electrically insulating block, and a pair of current supply pairs is provided on both ends in a direction along a flange portion of the block in the same plane as the upper surface of the block. A bonding device for hemmed panels, wherein electrodes are embedded.