JPH0134627Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a technology for interconnecting pipe materials that constitute the body frame of small vehicles such as motorcycles and tricycles.

When a pipe frame is adopted as the body frame of a motorcycle, the connection of each frame pipe is as follows.
Using a lug, weld the lug and frame pipe,
Or join by soldering or omit the lug,
Join by direct arc welding. This joining causes the frame pipes or lugs to become red-hot over a wide area and tends to cause thermal distortion, which must be corrected after joining. This correction requires large processing equipment and increases the number of man-hours, leading to an increase in costs.

Furthermore, when a frame pipe made of light alloy material is used, it is easy to generate pores in the weld metal, entrainment of slag, weld cracks, etc., and requires a skilled welding engineer.

The present invention was devised under such circumstances, and is intended to provide a pipe material connection technique that does not rely on welding.

The structure of the present invention is such that the head pipe has a plurality of protruding branch pieces each having a first pipe fitting groove on its side surface, and a second pipe fitting groove that is paired with the first pipe fitting groove. Join the cover members with adhesive,
It is characterized in that a frame pipe having a large diameter at the tip is joined and held with an adhesive in a locking hole formed by each pipe fitting groove and having a large diameter at the base.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 shows a part of a body frame of a motorcycle as a cutaway perspective view of a main part, and a head pipe 1 is connected to a pair of main pipes 13 and a pair of down tubes 18.

In order to clarify this connection relationship, the shape of each component will be explained.

Head pipe 1 (see Fig. 2): a head pipe main body 2, a pair of upper and lower branch pieces 3 protruding from the peripheral wall of the head pipe main body 2 in an open leg shape,
It is formed by 4. The branch pieces 3 and 4 are members having a substantially U-shaped cross section and have first pipe fitting grooves 5 and 6 on their outer surfaces, and the groove width of the first pipe fitting grooves 5 and 6 is , the groove width W on the base side is made larger than the groove width W ₀ on the tip side of the branch pieces 3 and 4, and the groove width at the peripheral wall surface position of the head pipe body 2 is made larger.
W _nax is maximum. In the figure, 3a and 4a indicate rivet holes.

Cover member 7 (see Fig. 3): formed by a curved base plate part 8 that covers the front surface of the peripheral wall of the head pipe body 2, and a pair of upper and lower branch pieces 9 and 10 extending from the base plate part 8 in a split-leg shape. Second pipe fitting grooves 11 and 12 extend from a part of the inner surface of the base plate 8 to the inner surfaces of each branch piece 9 and 10.
have. The branch pieces 9 and 10 are members having a substantially bowl-shaped cross section. Also, the second pipe fitting groove 1
1 and 12 are shaped to correspond to the first pipe fitting grooves 5 and 6 in the head pipe 1,
The groove width on the substrate portion 8 side is larger than the groove width on the branch pieces 9 and 10 side. In the figure, 9a and 10a indicate rivet holes.

Main pipe 13, down tube 18 (see FIG. 4; however, the down tube 14 is not shown because it has substantially the same shape as the main pipe 13): The main pipe 13 has a rectangular cross section, and A notch 16 is formed from the tip edge in a pair of opposing side walls 14 at the tip (end connected to the head pipe 1), and a wedge 17 is driven into the tip opening. That is, main pipe 1
3, at the tip, a pair of opposing side walls 15 expand outward and have a larger diameter than the other portions. In the figure, 14a indicates a rivet hole. The shape of the down tube 18 is the same as that of the main pipe 13, so a description thereof will be omitted.

The shapes of each member 1, 7, 13, and 18 are as described above, and the method of assembling each member will now be described. First, a structural adhesive (e.g., epoxy resin, acrylic resin) is applied to the outer periphery of the connecting portions of the pair of main pipes 13 and the pair of down tubes 18, and each branch piece 3, 4 of the head pipe 1 is
It fits into the first pipe fitting grooves 5 and 6 from the side. At this time, the large diameter portions of the main pipe 13 and the down tube 18 match and fit into the large groove width portions on the base side of the first pipe fitting grooves 5 and 6.

Next, a structural adhesive is applied to the inner wall surface of the cover member 7 except for the parts that contact the main pipe 13 and the down tube 18 (main pipe 13,
Adhesive has already been applied to the down tube 18), the head pipe body 2, and the main pipe 1.
3. Glue the cover member 7 over the down tube 18. At this time, the main pipe 13 and down tube 18 protruding from the first pipe fitting grooves 5 and 6 and the second pipe fitting grooves 11 and 12 are fitted into each other, and the second pipe fitting groove The side wall ends 11A, 12A of the first pipe fitting grooves 5, 6 are respectively covered and bonded.

Thereafter, the branch piece 3, the main pipe 13, and the branch piece 9 are mutually reinforced and connected with a rivet 19, and the branch piece 4, the down tube 18, and the branch piece 10 are mutually reinforced and connected with a rivet 20. In addition, rivet 1
9 and 20 also function as temporary bonding means during the curing process of the adhesive.

In this embodiment, the head pipe 1 and each pipe 1 are
3 and 18 are connected in the above connection relationship,
First and second pipe fitting grooves 5, 11 and 6, 1
The force in the direction of separating from the locking holes formed respectively in the main pipe 13 and the down tube 18
Even if the large diameter portion on the tip side is
Since it is regulated by the narrow portions of the second pipe fitting grooves 5, 6, 11, and 12, excessive shearing force does not act on the adhesive layer. Furthermore, even if a force that separates the branch piece 3 and the branch piece 9 and the branch piece 4 and the branch piece 10 is applied to the main pipe 13 and the down tube 18, each member will not adhere to the adhesive. Since the members are joined to each other by the rivets 19 and 20 and also reinforced by the rivets 19 and 20, the joining relationship between the respective members is maintained stably (good peeling resistance). Incidentally, such a force causes a bending moment to act on the branch pieces 3, 4 and the branch pieces 9, 10, but these members 3, 4, 9, 10 have a U-shaped cross section. Due to its high rigidity, it is difficult to deform.

Furthermore, in this example, each pipe material was joined with adhesive, so there is no thermal deformation that occurs when welding joints, and there is no need for strain relief treatment after joining, improving production efficiency. and cost reduction is achieved.

Furthermore, when a pipe material made of a light alloy material is used, which requires skilled skill to perform welding and joining, it is advantageous to adopt a joining structure using an adhesive as in this embodiment.

In the above embodiment, square pipes were used as the main pipe and down tube, but a similar connection structure can be obtained by using circular pipes, and wedges may be used for the tips of the main pipe and down tube. Instead, it may be formed into a large diameter during pipe manufacturing.

As is clear from the description of the embodiments above, in the present invention, for a head pipe having a plurality of protruding branch pieces each having a first pipe fitting groove on the side surface, a first pipe fitting groove and a pair are provided. A cover member having a second pipe fitting groove is bonded with adhesive, and a frame pipe having a large diameter at the distal end is inserted into a locking hole formed by each pipe fitting groove and having a large diameter on the base side. Since they are joined and held together with adhesive, there is no thermal deformation that occurs when pipe materials are connected by welding, and there is no need for post-distortion treatment, improving production efficiency. and cost reduction is achieved. Moreover, it has the advantage that it does not require skilled techniques compared to welding.

Moreover, since the base side of the locking hole is made large in diameter and the tip of the frame pipe is formed in a large diameter, even if a force is applied to the frame pipe in the direction of separating from the locking hole, , no excessive shearing force acts on the adhesive.

Furthermore, since the branch piece and the cover member each have the first and second pipe fitting grooves, their bending rigidity is high.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of the main parts of a motorcycle body frame according to an embodiment of the present invention, and FIG. 2 is a perspective view of its head pipe.
FIG. 3 is a perspective view of the cover member, and FIG. 4 is a perspective view of the main pipe. DESCRIPTION OF SYMBOLS 1... Head pipe, 2... Head pipe main body, 3, 4... Branch piece, 5, 6... First pipe fitting groove, 7... Cover member, 8... Base plate part, 9,
10... Branch piece, 11, 12... Second pipe fitting groove, 13... Main pipe, 14, 15... Side wall, 16... Notch, 17... Wedge, 18... Down tube, 19 ,20...Rivets.

Claims (1)

[Scope of utility model registration request] A head pipe having a plurality of protruding branch pieces each having a first pipe fitting groove on its side surface, and a plurality of second pipe fitting grooves forming a pair with each of the first pipe fitting grooves. and a plurality of frame pipes whose tip portions have a larger diameter than other portions, and the first pipe fitting groove has a cross-sectional dimension at the base of the branch piece. is made larger than the cross-sectional dimension at the tip, the second pipe fitting groove has a shape corresponding to the first pipe fitting groove, and the cover member has a shape that corresponds to the first pipe fitting groove. The frame pipe is adhesively bonded to the head pipe by covering the side surface of the piece and the head pipe body, and the plurality of frame pipes are bonded and held within the locking hole formed by the first and second fitting grooves using adhesive. The body frame of a small vehicle is characterized by: