JPS5827153B2 - Motorcycle frame structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a frame structure for a motorcycle with improved body rigidity.

More specifically, by connecting the head pipe holder fork attachment part and the head pipe holder cushion attachment part with linear frame members, the connection strength of each important part of the car body is increased, and the strength of the car body is improved. At the same time, the fuel tank is also used as a strength reinforcing member, and the space at the rear of the head pipe formed by each frame member is used as a storage area for electrical components, improving body rigidity and making effective use of space. Regarding the frame structure of motorcycles.

The important parts when considering the body rigidity of a motorcycle are the head pipe part, which is the center of rotation of the front fork that supports the front wheel, and the mounting part of the rear fork, which supports the rear wheel so that it can swing freely. This is the attachment part of the rear cushion that cushions the rear wheel, and these parts are connected by the frame to form the general frame of the vehicle body, and the connection strength of the frame members determines the overall rigidity and strength of the motorcycle body. Therefore, the frame that connects the above-mentioned parts becomes an extremely important element in terms of vehicle body rigidity.

Conventionally, the head pipe handler fork attachment part and the head pipe handler cushion attachment part are connected, for example, by a frame member formed by connecting a plurality of pipe members, or even if a single pipe member is used, it may be bent in the middle. However, sufficient consideration was not always given to the connection strength of the frame members and the rigidity of the vehicle body.

The present inventor took into consideration the frame structure, which is important when considering the body rigidity of such a motorcycle, and applied the present invention to improve the rigidity and strength of the vehicle body.

The object of the present invention is to connect the head vip and rear fork attachment area, which are important for vehicle body rigidity, and the head pipe catcher cushion attachment area, respectively, with linear frame members, thereby increasing the connection strength and making it possible to rely on the frame members. To provide a frame structure for a motorcycle designed to improve the rigidity and strength of a vehicle body.

Another object of the present invention is to form the frame member with one thick pipe at the center extending toward the rear of the vehicle body and two thin pipes on the left and right sides of this, and a head pipe formed inside these three pipes. A motorcycle frame structure in which the rear space is used to accommodate electrical components such as batteries, allowing electrical components to be assembled close to headlights, etc., thereby shortening the length of wiring cords such as harnesses. I will provide a.

A further object of the present invention is to extend the fuel tank from the vicinity of the head pipe of the vehicle body frame to the rear end, and by fixing the fuel tank to the top surface of the vehicle body frame, the fuel tank can also be used as a strength reinforcement member for the vehicle body. In addition to further improving rigidity and strength, the fuel tank capacity has been increased compared to its appearance, and the overall position of the fuel tank has been lowered to lower the center of gravity. Provides frame structures for motorcycles.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a side view showing the frame structure of a motorcycle and the arrangement of various devices such as an engine and a fuel tank, and FIG. 2 is a plan view of the frame structure and an electrical component box.

A front fork 2 supporting a front wheel 1 is connected to a head pipe 3, and three frame members 5, 6.degree. 7 extend from a connecting plate 4 fixed to the head pipe 3 toward the rear of the vehicle body.

The backbone frame of the vehicle body is formed by the three frame members 5.6.7, and in the illustrated embodiment, all the frame members 5.6.7 are made of pipe material, but are not limited to this, and may be made of sheet metal, for example. It may also be obtained by press molding materials.

As shown in Fig. 2, the central frame member 6 among the three is formed of a thick pipe, and the two frame members 5 on the left and right sides of this
, 7 are formed of thin pipes, and the front ends of the frame members 5, 7 made of thin pipes are fixed to the upper side of the head pipe 3 via a connecting plate 4 as shown in FIG. The angle is tilted downward to the right in Figure 1.

Further, the end of the central frame member 6 made of a thick pipe is fixed to the head pipe 3 below the frame members 5 and 7, and is inclined downward to the right at a gentle angle.

As a result, the three frame members 5, 6, 7 intersect in a substantially X-shape, and these members 5, 6, 7 are arranged before and after the intersection point.
An upward space S1 and a downward space S2 surrounded by 6 and 7 are provided, and as shown in FIG.

A bottom plate 9 and a rear frame 10 are fixed to the rear ends of the frame members 5 and 1, and a rear wheel 11 is attached to the bottom plate 9.
Mounting part 1 of the rear fork 12 that supports the vertically swingable
2a is provided, thereby connecting the head pipe 3 and the vicinity of the rear fork attachment portion 12a with straight frame members 5 and 7.

The rear frame 10 is bent rearward by the upper force of the fixed parts of the frame members 5 and 7, and a mounting bracket 13 is fixed to this bent part, and a rear cushion 1 is installed to buffer the vertical movement of the rear wheel 11.
The pivot pipe 15 of No. 4 is installed on this bracket 13 as shown in FIG.
is connected to the bracket 13.

The rear end of the central frame member 6 is connected to the pivot pipe 15.
The head pipe 3 and the vicinity of the rear cushion attachment portion 14a are thereby connected by one linear frame member 6.

A hanger 16 is suspended and fixed to the cross member 8, and a second
As shown in the figure, a mounting plate 18.18 is provided on the bottom pipe 17 which is installed across the two left and right frame members 5 and 7, and the engine 19 is mounted on the hanger 16 and the mounting plate 1-18.18.
At the same time, the engine 19 is also connected to the mounting portion 9a of the bottom plate 9.

An electrical component box 20 having a cover plate 20a provided on the upper surface so as to be openable and closable is installed in the upward space S1.

This box 20 has a locking part 20 at the tip as shown in FIG.
b are each provided with a bolt insertion hole 20c at the rear, the locking part 20b is fitted and locked to a locking fitting 21 fixed to the support frame 6, and the bolt is inserted into the hole 20c and screwed to be assembled to the vehicle body.

Necessary electrical equipment such as an ignition coil 21, a battery 22, a CDI unit 23, etc. are housed in the box 20, and a tool housing box 24 is provided inside, so that the electrical component box 20 also serves as a tool housing.

As described above, the space S1 formed by the frame members 5, 6, and 7 arranged in an X-shape becomes an electrical equipment housing part, and the space is used effectively, and since the top surface is open, maintenance of electrical equipment is facilitated. The top is also convenient.

Also, since this space S1 is close to the head pipe 3, it is close to the headlight and various meter devices installed in front of the head pipe 3, and the wiring cords and harnesses can be shortened accordingly.

Further, the electrical equipment box 20 faces the upper part of the oil tank 25, and the oil tank 25 is housed so as to be inserted into the interior space of the fuel tank 26, which is formed into a saddle shape with a substantially inverted U-shaped cross section. As shown in FIG. 5, the front part is connected to the support member 27 of the cross member 8 with a screw 28, and
Fix the rear part to the frame member 6 with.

Therefore, the oil tank 25 is assembled at the same position as various electrical components, and oil can be poured into the tank 25 by opening the cover plate 20a of the electrical component box 20, making this operation easy.

On the other hand, an air cleaner 30 is installed in the downward space S2.

The upper part of this air cleaner 30 is connected to the projection 31 of the frame member 6 with screws 32 as shown in FIG.

Further, the bottom plate 9 has a pair of hanging pieces 33 33 on its lower surface and is fixed to the two left and right frame members 5 and 7.
A support rod 34 is installed through the air cleaner 9, and the lower part of the air cleaner 30 is fixed by inserting the support rod 34 through the hanging pieces 33, 33.

As described above, the rear space S2 formed by the frame members 5, 6.7 is used as an air cleaner accommodating part, and the air cleaner 30 with a larger capacity than before can be installed, and this air cleaner 30 also functions as a side cover. This eliminates the need for a side cover that has no special function other than appearance.

The fuel tank 26 has a large part 26a in the front part and a large part 26a in the front part and the seat 3.
5 and a flat portion 26b extending rearward from the lower surface of the bulge 26a and being one step lower than the enlarged portion 26a.

A pair of brackets 36.
The front portion of the fuel tank 26 is fixed to the vehicle body by inserting a bolt 37 into the hole 8a of the cross member 8 and screwing it into the hole 8a of the cross member 8.

Further, an extension plate 38 extending rearward is integrated at the rear of the flat portion 26b.

A pair of rear frames 10 are provided at the rear end of the rear frame 10.
10 and fix the cross plate 39, interpose a cushioning material 40 such as rubber between the extension plate 38 and the cross plate 39, and attach the rear part of the fuel tank 26 to the vehicle body with bolts 41 as shown in Fig. 1. Join.

In this case, as shown in FIG. 7, a cushioning material 42 such as rubber is also interposed between the bracket 13 provided on the rear frame 10 and the tank bottom plate 26c.

As described above, the fuel tank 26 is fixed so as to cover the upper surface of the frame members 5.6.7 and the rear frame 10 that constitute the vehicle body frame over almost the entire length, and is attached to the frame members 5, 6, and 7 from the vicinity of the head pipe 3. By extending to the rear end and connecting the front and rear to the vehicle body frame in this manner, the fuel tank 26 becomes a reinforcing member for the vehicle body frame, and the strength of the vehicle body is improved.

Furthermore, even if the electrical component box 20 is provided in the front part, the fuel tank 26 is
The capacity of the fuel tank 26 can be increased, and the height position of the fuel tank 26 relative to the vehicle body can be lowered as a whole, allowing the center of gravity to be lowered.

An engaging piece 43 is provided at the front of the flat part 26b of the fuel tank 26 as shown in FIG. The extension plate 38 of the fuel tank 26 and the seat bottom plate 35a are fixed with screws 45, and the seat 35 is attached to the upper surface of the lower flat part 26b of the fuel tank 26.

As a result, the rear upper surface of the fuel tank 26 has a surface where the seat 35 is received, and the seat 35 has an inverted U-shaped cross section.
The lower edge 35b covers both left and right sides of the flat part 26b, and only the enlarged part 26a at the front of the fuel tank 26 is exposed to the outside.
The rear flat portion 26b is not exposed.

Therefore, compared to the external size of the tank 26, the fuel tank capacity can be increased by the amount of the flat portion 26b as described above.

The rear extension plate 38 of the fuel tank 26 is formed into a channel shape as shown in FIG. 8, and has side plates 38a and 38 on both sides.
a is formed.

The rear end 46, which is integrated with the seat cowl attached to the rear of the vehicle body, is provided with left and right protruding plates 46a, 46a protruding from the front as shown in FIG.

46a is the side plate 38a of the extension plate 38 as shown in FIG.

38a, and screw both 38a and 46a with screw 4.
Combine with 7.

Further, upper and lower clamping pieces 48 and 49 are formed at the rear end of the extension plate 38, and a retaining piece 50 of the rear fender 46 is fitted between the clamping pieces 48 and 49, and the extension plate 38 is connected to the fuel tank 26. A rear fender 46 is attached, and the tank 26 is also used as a rear fender attachment member.

As is clear from the above description, according to the present invention, the head pipe portion, rear fork mounting portion, and rear cushion mounting portion, which are important for vehicle body rigidity, are connected by linear frame members, thereby improving the strength of the vehicle body. This improves the connection strength of the frame members, increases the degree of connection from the head pipe to the rear wheel axle, improves the handling stability of the motorcycle, and makes the intersection points of the frame members more effective. Since the upper part of the engine is suspended and supported, the rigidity and stability of suspending the engine can also be increased.

In addition, since the space at the rear of the head pipe formed by the frame member is used as the electrical component housing section, effective use of space can be achieved, and the wiring cords and harnesses from the electrical components to the headlight etc. can be shortened.

Furthermore, since the fuel tank extends from near the head pipe of the body frame to the rear end and is fixed to the body frame, this tank serves as a reinforcing member for the body frame, improving the rigidity of the frame and lowering the center of gravity. , it is extremely beneficial to improve the stability of motorcycles, etc.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a side view showing the frame structure and the arrangement of the engine, etc., Fig. 2 is a plan view of the frame structure and electrical component box, and Fig. 3 is an exploded perspective view. , Figure 4 is a sectional view taken along the line 4-4 in Figure 1, and Figure 5 is a cross-sectional view taken along line 4-4 in Figure 1.
6 is a sectional view taken along line 6-6, FIG. 7 is a sectional view taken along line 5-5, and FIG. 8 is a sectional view taken along line 8-8. In the drawing, 3 is a head pipe, 5, 6.7 are frame members, 12 is a rear fork, 14 is a rear cushion, 26
is a fuel tank, and Sl is a space for accommodating electrical components.

Claims (1)

[Scope of Claims] 1. The lower part of the head pipe and the vicinity of the rear cushion attachment part are connected by one straight frame member, and the upper part of the head pipe and the vicinity of the rear cushion attachment part below the rear cushion attachment part are connected. , the frame member is connected by two straight frame members spaced apart from each other on the left and right sides of the frame member, and the engine is connected to the lower surface of the frame member at a point where the one frame member and the two frame members intersect. A frame structure for a motorcycle characterized by suspension support at the upper part. 2. In claim 1, the frame member is composed of one thick pipe at the center and two thin pipes on both left and right sides, and the rear part of the head pipe formed by the plurality of frame members is A frame structure for a motorcycle, characterized in that a space is used as an electrical equipment housing part. 3. Claim 1 is characterized in that a fuel tank extends from the vicinity of the head pipe to the rear of the vehicle body frame formed by the frame member, etc., and the fuel tank is covered and fixed to the vehicle body frame. Motorcycle frame structure.