JPH04107113A - Method for jointing fiber-reinforced resin molded item - Google Patents

Abstract

PURPOSE:To make it possible to bend a molded fiber-reinforced resin molded panel to a frame of a vehicle body without opening biss holes by a method wherein a plate part of an inserting member is exposed above one of the faces of the panel and plurality of apexes of pins penetrating the sheet-like part from the other face are projected. CONSTITUTION:An inserting member 1 constituted of a round plate part 2 made of a steel having a flat upper face 2a and a rear face 2b and steel pins 3 planted vertically on the rear face 2b are fixed on the rear face 4a of a top force 4 of a mold. Then, the top force 4 is lowered to perform mold clamping. Then, a thermosetting resin material is injected in the mold and the voids between long fibers are filled with the resin to mold a fiber-reinforced resin molded panel 9. An upper face 2a of the round plate part 2 is exposed above an upper face 9a and apexes 3a of the pins 3 are projected on the rear face 9b. Then, spot welding is performed while a pressure is applied on chips 11 and 12 under a condition wherein the apexes 3a of the pins 3 projected from the rear face 9b of the molded panel 9 is brought into contact with the upper face 10a of a steel sheet 10 bonded with this molded panel 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a joining method for joining a fiber-reinforced resin molded product to a conductive member.

(Prior Art) In recent years, for the purpose of reducing the weight of automobile bodies, there has been a trend to employ fiber-reinforced resin molded panels for body outer panels such as bonnets or fenders.

Such a resin molded panel is disclosed in, for example, Japanese Patent Application Laid-Open No. 61172.
As disclosed in Publication No. 725, it is joined to the vehicle body frame etc. via screws, but when drilling screw holes in this resin molded panel, the reinforcing fibers inside the panel are cut. There was a problem in that the strength of the joint was reduced.

(Object of the Invention) Therefore, an object of the present invention is to provide a joining method that allows joining a fiber-reinforced resin molded panel to a vehicle body frame, etc., without drilling screw holes or the like in the panel.

(Structure of the Invention) In the method of the present invention, first, a conductive metal plate and a plurality of conductive metal pins implanted on one surface of the plate while maintaining electrical continuity with the plate are used. A conductive insert member made of the following is prepared. Next, this insert member is set in a mold while being attached to a mat material pre-formed from long fibers for resin reinforcement. In this case, the insert member is attached to the mat material with the plurality of pins passing through the mat material from one surface to the other surface. Next, a thermosetting resin material is injected into a molding die to form a fiber-reinforced resin molded panel. In this case, the surface of the plate portion of the insert member is exposed on one surface of the resin-molded panel, and the tips of the plurality of pins of the insert member protrude from the other surface. Next, spot welding is performed with another conductive member in contact with the tips of the plurality of pins protruding from the other surface of the panel to join the panel to the other conductive member. Features.

(Effects of the Invention) According to the present invention, the plate portion of the insert member is exposed on one surface of the molded fiber-reinforced resin molded panel, and the plurality of pins electrically connected to the plate portion from the other surface are exposed. Since the tip is protruding, it is extremely easy to spot weld this insert member to another conductive member, thereby making it possible to firmly join the resin molded panel to the other conductive member. In addition, since the pin of the insert member is inserted through long fibers or unfixed long fiber mat material,
There is no fear that the pins will cut the long fiber material, and together with the fact that the plurality of pins of the insert member penetrate the joint, the strength of the joint can be significantly improved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 2 and 3 show an example structure of an insert member used in the present invention, and this insert member 1 includes a steel disk portion 2 having a flat upper surface 2a and a lower surface 2b, and a steel disk portion 2. It is composed of eight steel pins 3 installed vertically on the lower surface 2b of the. These 8 pins 3
is electrically connected to the disk portion 2, and the tip of the pin 3 forms a sharp point 3a. The dimensions of the insert member 1 in this example are that the diameter of the disc portion 2 is 8+nm and the thickness is 0.1 mm, the diameter of the pin 3 is 0.6 mm, and the length is 2.5 mm including the tip portion 3a. , the length of the pointed end 3a is 0.5 mm.

The insert member 1 having such a configuration is shown in FIG.
It is attached to the lower surface 4a of the upper die 4 of the molding die shown in A). A permanent magnet 5 is buried in a proper position on the lower surface of the upper die 4, and the insert member 1 is attracted to its disk portion 2 by the permanent magnet 5, and is held with the pin 3 facing downward. On the other hand, on the upper surface 6a of the lower mold 6 of the molding die, a mat is formed in advance to a predetermined thickness to match the shape of the cavity of the molding die using long fibers for resin reinforcement such as glass fiber or carbon fiber. Set material 7. Note that a recessed hole 8 having a depth of about 05 mm is formed in the upper surface of the lower mold 6 to allow the pointed end 3a of the pin 3 of the insert member 1 to escape.

Next, the upper mold 4 is lowered and the mold is clamped as shown in FIG. 1(B). As the mold is clamped, the pin 3 of the insert member 1 penetrates from the upper surface 7a to the lower surface 7b of the long fiber mat material 7, and its tip 3a protrudes from the lower surface 7b of the mat material 7. Next, as shown in Fig. 1(C), a thermosetting resin material is injected into the mold to fill the spaces between the long fiber materials, and a fiber-reinforced resin molding molded with a thickness of 2 mm is made. Form 8 flannel 9. The upper surface 2a of the disk portion 2 of the insert member 1 is exposed on the upper surface 9a of the molded panel 9, and the tip portions 3a of the eight pins 3 of the insert member 1 protrude from the lower surface 9b of the molded panel 9. The state will be as follows.

Next, as shown in FIG. 1(D), the lower surface 9 of the molded panel 9
With the upper surface 10a of the steel plate 10 to be joined to the formed panel 9 in contact with the pointed end 3a of the pin 3 protruding from The other chip 12 is brought into contact with the upper surface 2a.
Spot welding is performed while applying pressure to the tips 11 and 12 while contacting the lower surface 10b of the steel plate 10 at a position opposite to the tips 11. By this spot welding, the tip 3a of the pin 2 of the insert member 1 melts and fuses with the steel plate 10, as shown in FIG.
The lower surface 9b of the steel plate 10 and the upper surface 10a of the steel plate 10 are firmly joined with each other in close contact with each other.

As is clear from the above description, in this embodiment, the pins 3 of the insert member 1 penetrate the long fiber mat material 7 in which the long fiber material is movable prior to forming the panel 9. Therefore, there is no fear that the long fiber material will be cut by the pins 3, and the insert member 1 is not inserted into the upper mold 4.
By clamping the insert member 1 while holding it on the lower surface 4a of the mat member 7, the insert member 1 can be attached to the mat member 7 at the same time as clamping the insert member 1.

Furthermore, by forming the tip of the pin 3 into a pointed portion 3a, even if a film of resin material adheres to the tip of the pin 3 during molding of the resin-molded panel 9, the pointed portion 3a of the pin 3 can easily remove the film. Since it can be penetrated, there is no risk of non-conductivity between the tips 11 and 12 during spot welding.

[Brief explanation of the drawing]

FIGS. 1A to 1E are cross-sectional views illustrating an embodiment of the present invention in the order of steps, and FIGS. 2 and 3 are a bottom view and a side view of the insert member. 1... Insert member 2... Disk portion of insert member 3... Pin 3a of insert member... Pin tip 4... Upper die 5... Permanent magnet 6... Lower die 7... Long fiber mat material 9... Fiber reinforced resin molded panel 10... Steel plate

Claims (1)

[Claims] A conductive insert member is prepared which includes a conductive metal plate and a plurality of conductive metal pins implanted on one surface of the plate while maintaining electrical continuity with the plate. and setting this insert member in a mold with the plurality of pins passing through the long fiber mat material from one side of the long fiber mat material to the other side and attached to the long fiber mat material, A thermosetting resin material is injected into the mold to expose the plate portion of the insert member on one surface, and the tips of the plurality of pins of the insert member protrude from the other surface. A fiber-reinforced resin molded panel is molded, and spot welding is performed with another conductive member in contact with the tips of the plurality of pins protruding from the other surface of the panel. A method for joining fiber-reinforced resin molded products, the method comprising joining another conductive member to the resin molded panel.