JP3444052B2 - Reinforcement structure of motorcycle pipe frame - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for reinforcing a motorcycle pipe frame. 2. Description of the Related Art As a vehicle body frame employed in a motorcycle, a pipe frame obtained by combining a plurality of steel pipe members is generally used. In the pipe frame, stress is particularly concentrated on the joint of the pipe members near the head pipe that supports the steering mechanism. Therefore, a bridge member or a reinforcing member is welded to secure the joint strength. I have. FIGS. 6 (a) and 6 (b) show a reinforcement structure of a pipe frame which has been generally used in the past. For example, a down tube 1 which is a pipe member,
A bridge pipe 2 which is a pipe member is erected between a tank rail (not shown) and a reinforcing member 3 formed by bending a steel plate into a U-shaped cross section at a connection between the bridge pipe 2 and the down tube 1. And the respective joints are welded. [0005] However, in the conventional reinforcing structure, the welding mark 4 at the joint between the pipe members 1 and 2 and the reinforcing member 3 is also exposed to the outside of the vehicle body, and the appearance is reduced. There was a problem of spoiling. Therefore, as shown in FIGS. 6 (c) and 6 (d), a reinforcing member 5 made of a flat steel plate is connected to the connecting portion between the down tube 6 as a pipe member and the bridge pipe 7 inside the vehicle body. There is an improvement plan in which the welding marks 8 are not visible from the outside of the vehicle body by welding the respective joints by contacting with each other. However, the joining between the pipe members 6 and 7 and the reinforcing member 5 outside the vehicle body is known. A gap 9 is formed in the gap, and further, it is difficult for the coating to enter the gap 9, and there is a possibility that rust is generated in the gap 9 to impair the appearance. The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a motorcycle pipe frame reinforcing structure having an improved appearance. [0008] In order to solve the above-mentioned problems, a reinforcement structure for a motorcycle pipe frame according to the present invention has the following features .
To the tank rail and down tube that constitute the front part
Bridge pipe consisting of pipe members
Erect the bridge pipe and the down tube
Set the connection angle of the connection part to 90 ° or more, and
A reinforcing member made of steel plate material is arranged at the connection part, and each
Of the pipe frame for motorcycles where the above connections are welded
In the reinforcing structure, the joining end of the reinforcing member to the pipe member is disposed inside the vehicle body, bent along the outer peripheral surface of the pipe member, and then bent so as to be parallel to the axis of the pipe member. In addition, the bent portion of the reinforcing member is set such that the center line of the reinforcing member is offset to the outside of the vehicle body with respect to the axis of the pipe member. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a left side view showing an example of a motorcycle to which the present invention is applied. Referring to FIG. 1, a motorcycle 11 has a body frame 12, and an engine 13 is mounted at a lower center portion of the body frame 12. A fuel tank 14 is provided above the engine 13, and an operation seat 15 is provided behind the fuel tank 14. A head pipe 16 is provided in front of the body frame 12, and a steering mechanism 17 is provided on the head pipe 16. The steering mechanism 17 includes a front fork 1 that rotatably supports a front wheel 18.
9 and the handlebar 20 are provided.
Is pivotally attached to the left and right. On the other hand, a swing arm 23 for rotatably supporting a rear wheel 22 is pivotally mounted on a pivot shaft 21 erected at a lower center portion of the body frame 12 so as to swing around the pivot shaft 21. FIG. 2 is a side view of the vehicle body frame 12, and FIG. 3 is a perspective view of the vehicle body frame 12. As shown in FIGS. 2 and 3, the body frame 12 employed in the motorcycle 11 has a double cradle type structure composed of a pipe frame in which a plurality of steel pipe members are combined, and mainly includes a head pipe 16. And a pair of tank rails 24 as pipe members and a pair of down tubes 2
5, a pair of seat rails 26 and a pair of center pillar tubes 27. The front ends of both tank rails 24 are connected to the upper rear part of the head pipe 16 so as to expand right and left, and extend obliquely downward. The distal ends of both down tubes 25 are connected to the lower rear portion of the head pipe 16 and expand left and right, extend substantially downward, bend, and extend substantially horizontally rearward. From the rear end of each down tube 25, a seat rail 26 is extended obliquely upward and then bent, and then extends substantially horizontally toward the rear. The tank rail 2 is located near the bent portion of the seat rail 26.
4 is connected, and a center pillar tube 27 is erected between a middle portion of the tank rail 24 and a lower surface slightly rearward and a connection portion between the rear end of the down tube 25 and the seat rail 26. You. FIG. 4 is an enlarged perspective view of the front part of the vehicle body frame 12, and as shown in FIGS.
A bridge pipe 28 as a pipe member is installed near the head pipe 16 of the down tube 25. A reinforcing member 29 made of a steel plate material also serving as a mounting bracket for an auxiliary device (not shown) is applied to the connection between the bridge pipe 28 and the down tube 25 from the inside of the vehicle body. You. The connection angle θ between the down tube 25 and the bridge pipe 28 is 90
° or higher. FIG. 5 is a sectional view taken along the line V--V in FIG. As shown in FIG. 5, the reinforcing member 29 has a joint end 30 thereof.
Is arranged inside the vehicle body and bent along the outer peripheral surface of the down tube 25, and then the axis 31 of the bridge pipe 28 is
It is bent backward so as to be parallel to. Also,
The bent portion 32 of the reinforcing member 29 is located at the center line 33 of the reinforcing member 29.
Is set so as to be offset to the outside of the vehicle body with respect to the axis 31 of the bridge pipe 28. Next, the operation of the present embodiment will be described. By disposing the joint end 30 of the reinforcing member 29 inside the vehicle body and welding the joint with the down tube 25, the welding mark 34 becomes invisible from the outside of the vehicle body and the appearance is improved. The reinforcing member 29 is connected to the down tube 25.
After being bent along the outer peripheral surface of the bridge pipe 28, and in the rearward direction so that the center line 33 of the reinforcing member 29 is offset outside the vehicle body with respect to the axis 31 of the bridge pipe 28. By bending toward
The gap 35 formed at the joint between the down tube 25 and the reinforcing member 29 on the outer side of the vehicle body is easily coated with paint, and rust is prevented from being generated in the gap 35, so that the appearance is improved and the rigidity and durability of the joint are improved. Increase. Further, since a plate material is used for the reinforcing member 29, it is easier to attach an auxiliary device and the like, and the number of parts such as brackets can be reduced as compared with a conventional member having a U-shaped cross section. The cost and weight of the body frame 12 can be reduced. As described above, according to the motorcycle pipe frame reinforcing structure of the present invention, the motorcycle body frame composed of a pipe frame obtained by combining a plurality of steel pipe members is provided. In a motorcycle, a reinforcing member is disposed at a connecting portion between the pipe members, and the respective joints are welded. On the other hand, the reinforcing member has a connecting end to the pipe member disposed inside the vehicle body, and the After being bent along the outer peripheral surface, the pipe is bent so as to be parallel to the axis of the pipe member, and the bent portion of the reinforcing member is formed such that the center line of the reinforcing member is aligned with the axis of the pipe member. Since it is set to be offset to the outside, welding marks are not visible from the outside of the car body and the appearance is improved, and the gap created at the joint between the pipe member and the reinforcement member on the outside of the car body is This makes it easier to paint and prevents rust from forming in these gaps, improving the appearance and improving the rigidity of the joints,
Increases durability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a left side view of a motorcycle showing one embodiment of a motorcycle pipe frame reinforcing structure according to the present invention. FIG. 2 is a side view of the vehicle body frame. FIG. 3 is a perspective view of a vehicle body frame. FIG. 4 is an enlarged perspective view of a front portion of a vehicle body frame. FIG. 5 is a sectional view taken along the line VV in FIG. 4; 6A is a side view showing an example of a conventional pipe frame reinforcing structure, FIG. 6B is a cross-sectional view taken along line bb thereof,
(C) is a side view showing another example of a conventional pipe frame reinforcing structure, and (d) is a cross-sectional view along the line dd. DESCRIPTION OF SYMBOLS 11 Motorcycle 12 Body frame 16 Head pipe 24 Tank rail (Pipe member) 25 Down tube (Pipe member) 28 Bridge pipe (Pipe member) 29 Reinforcement member 30 Reinforcement member joining end 31 Bridge pipe (Pipe member) ) Axis 32 bending part 33 of reinforcing member center line of reinforcing member

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B62K 19/06 B62K 19/20 B62K 19/28

Claims (1)

(57) [Claims] [Claim 1] A tank tank constituting a front portion of a body frame
Pipe near the head pipe of
A bridge pipe consisting of members is installed, and this bridge
The connection angle of the connection between the pipe and the down tube is 90
° or more, and a steel plate
Reinforcement members are arranged, and the above-mentioned connection portions are welded.
In the reinforcement structure of the motorcycle pipe frame,
After arranging the joint end of the reinforcing member to the pipe member inside the vehicle body and bending along the outer peripheral surface of the pipe member ,
While bending so that it is parallel to the axis of the pipe member ,
Centerline above path of the reinforcing member the bent portion of the reinforcing member
Reinforcement structure of a pipe frame for a motorcycle, characterized in that the set to be offset on the outer side of the vehicle body against the axial line of the type member.