JPH0649505Y2 - Body frame structure of motorcycle - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] In this invention, a head pipe and a rear member of a vehicle body are connected by a pair of left and right main frames, and each main frame surrounds an engine of a motorcycle. The present invention relates to a vehicle body frame structure (double cradle type frame structure) of a motorcycle.

[Conventional technology]

Conventionally, by welding and fixing the front end of the fuel tank to the head pipe and the rear end to the seat rail,
It is known that a fuel tank is used as a reinforcing member for a vehicle body frame and a reinforcing member such as a main pipe is omitted (see Japanese Patent Laid-Open Nos. 51-81332 and 51-66640).

Further, a structure in which the front and rear portions of a fuel tank are detachably fixed to a vehicle body frame via bolts is disclosed (Japanese Patent Publication No. Sho.
58-27153 publication).

[Problems to be solved by the device]

However, according to the former configuration, since the fuel tank is welded and fixed to the vehicle body frame, it is impossible to remove the fuel tank from the vehicle body, and it is difficult to maintain and inspect the engine and the like.

On the other hand, according to the latter configuration, although the fuel tank can be removed from the vehicle body frame, the weight of the entire vehicle body cannot be reduced because there is a thick pipe as a strength reinforcing member in the center of the vehicle body frame. Not only that, but the above pipes hinder the maintenance and inspection of the engine.

The present invention has been made to solve the above-mentioned problems, and is a motorcycle that is lightweight, yet has the required strength, and that allows for easy maintenance and inspection of the engine and the like when necessary. An object is to provide a vehicle body frame structure.

[Means for Solving the Problems]

The motorcycle body frame structure according to the present invention is provided with a pair of left and right lower main frames that connect the head pipe and the vehicle body rear member, and is arranged above and facing the lower main frames. A fuel tank, a first mounting plate fixed to the front and rear portions of the fuel tank, and second mounting plates fixed to the head pipe and the vehicle body rear member in correspondence with the first mounting plate, A fastening member that removably fastens the first mounting plate to these second mounting plates is provided, and the first and second mounting plates are fastened by the fastening member so that the fuel tank is on the upper side. A main frame is also provided, and the engine of the motorcycle is surrounded by the lower main frame and the fuel tank.

[Action]

According to the above configuration, since the fuel tank is also used as the strength member of the vehicle body frame, the strength member and the reinforcing member used to secure the strength required for the vehicle body frame such as the main pipe are omitted. It is possible,
It is possible to secure the necessary strength as a motorcycle while making the whole lightweight.

Also, the fuel tank can be easily detached from the vehicle body frame by releasing the fastening of the front and rear parts of the fuel tank. Maintenance and inspections can be performed easily and reliably in a large work space.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of a vehicle body frame structure showing an embodiment of the present invention.

In the figure, a fuel tank 1 has a fuel filler port 2 on the upper portion thereof, and a first mounting plate 3A, 3
B is projected by welding and these mounting plates 3A,
Mounting holes 4A and 4B are formed in 3B.

The vehicle body frame 5 is composed of a head pipe 6, front and rear portions 7a and 7b from which a pair of upper tubes 7 are removed, a pair of lower tubes 8 and a vehicle body rear member 5C such as a seat rail 9 and a back stay 10.

Second mounting holes 11A and 11B are welded and fixed to the front and rear portions 7a and 7b of the body frame 5 so as to correspond to the mounting plates 3A and 3B of FIG. The mounting plates 11A, 11B are provided with mounting holes 12A, 12B while protruding.

The first mounting plates 3A, 3B are directly brought into contact with the second mounting plates 11A, 11B at their flat surfaces, so that the bolts 13A, 13B and nuts 1 are not in contact with each other.
The fastening members 15 and 16 made of 4A and 14B are detachably and firmly fastened.

That is, the bolts 13A, 1 are attached to the mounting holes 4A, 4B, 12A, 12B formed in the first and second mounting plates 3A, 3B, 11A, 11B, respectively.
The fuel tank 1 is detachably and firmly fastened to the vehicle body frame 5 by the fastening members 15 and 16 by inserting the nut 3A and screwing the nuts 14A and 14B into the tips of the bolts 13A and 13B.

In this way, the first mounting plate 3 protruding from the fuel tank 1
A, 3B and the second mounting plate 11A, protruding from the vehicle body frame 5,
Since the 11B and the fastening members 15 and 16 are detachably fastened, the fastening members 15 and 16 are unfastened, and the fuel tank 1 is removed from the vehicle body frame 5. Since it will be opened, the engine (not shown) attached to the lower tube 8 etc. can be installed and removed easily, or the maintenance and inspection with the engine installed can be done easily and reliably in a large work space. You can

Further, since the first and second mounting plates 3A, 3B, 11A, 11B are directly contacted and firmly fastened by the fastening members 15, 16, the fuel tank 1 is rigidly fixed to the vehicle body frame 5. Thus, it can be used as a rigid member of the vehicle body frame 5 and can also serve as the upper tube 7.

Accordingly, the weight of the vehicle can be reduced by omitting the upper tube 7.

[Effect of device]

As described above, according to the present invention, since the fuel tank is also used as the strength member of the vehicle body frame, the strength member used to secure the strength required for the vehicle body frame such as the main pipe, The reinforcing member can be omitted, and the required strength as a motorcycle can be secured while making the overall weight lightweight.

Further, since the fuel tank can be easily detached from the vehicle body frame by releasing the fastening of the front and rear portions of the fuel tank, it is possible to attach or detach the engine mounted in the space surrounded by the frame member, or Maintenance and inspection with the engine installed can be performed easily and reliably in a large work space.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a vehicle body frame structure showing one embodiment of the present invention, and FIG. 2 is an assembled perspective view of the vehicle body frame structure. 1 ... Fuel tank, 1A ... Fuel tank front part, 1B ... Fuel tank rear part, 3A, 3B ... First mounting plate, 5 ... Body frame, 5C ... Body rear member, 6 ... Headpipe,
7 ... Upper tube (upper main frame), 7a ...
… Front part of the upper main frame, 7b …… Rear part of the upper main frame, 8 …… Lower tube (lower main frame), 11A, 11B …… Second mounting plate, 15,16 …… Fastening members.

Claims (1)

[Scope of utility model registration request] 1. A pair of left and right lower main frames which connect a head pipe and a rear member of a vehicle body, and a fuel tank which is arranged above the lower main frames so as to face the lower main frames.
First mounting plates fixed to the front and rear of the fuel tank,
Second mounting plates fixed to the head pipe and the rear member of the vehicle body corresponding to the first mounting plate, and a fastening member for removably fastening the first mounting plate to the second mounting plates. And the first and second mounting plates are fastened together by the fastening member so that the fuel tank also serves as an upper main frame, and the lower main frame and the fuel tank are automatically two-wheeled. A body frame structure for a motorcycle, characterized in that it is configured to surround a vehicle engine.