JPH03224885A - Fuel tank device for motor-bicycle - Google Patents

Abstract

PURPOSE:To increase the capacity of a tank and to improve its operating ability in the above mentioned device for a motor-bicycle having an accommodating box on a middle upper part of a car body by joining upper and lower half tanks to form a front half part into the bottom part and the thickest part having arranged fuel supply cocks and to form the rear end part of the tank into the highest part provided with a fuel pouring port and arranged below a seat. CONSTITUTION:A fuel tank 17 is composed of an upper half tank 17a and a lower half tank 17b which are seam-welded through a flange 20. The upper face of the tank 17 is formed along a seat rail, and its bottom face is formed along the front upside of a rear wheel and inclined high backward so that the tank 17 may be accommodated in a body cover under a seat, and the bottom part is formed in a front half part, and the upper and lower sides of the tank 17 are formed to have the maximum thickness. A pouring port 21 is arranged at the highest position at the rear end of the upper half tank 17a, and a fuel supply cock 23 is arranged at the bottom part of the front half part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fuel tank device for a two-wheeled motor vehicle in which a storage box is arranged at the upper center of the vehicle body.

(Conventional technology) The general layout of motorcycles is that the engine unit is mounted below the main tube extending rearward from the head pipe, and the seat is mounted on a seat rail connected rearward from the rear end of the main tube. A storage box that can store large items such as a full-face helmet.
It is located on the main tube between the head pipe and the seat, and the fuel tank is located below the seat.

In this case, the rear wheels are located below the seat and space is tight, so it is difficult to find a fuel tank that can secure sufficient capacity in terms of shape and installation, or the placement of an easy-to-operate filler port or fuel supply cock. There was a problem.

(Problems to be solved by the invention) This invention is intended to solve such problems.
The shape and production direction of the fuel tank are appropriately set, making it possible to utilize even the slightest dead space, increasing the capacity, and installing the fuel inlet and fuel supply cock for easy operation. The purpose is to obtain a fuel tank device.

[Structure of the invention]

(Means for Solving the Problems) In order to satisfy the above object, the fuel tank device for a motorcycle of the present invention includes an engine unit mounted below a main tube extending rearward from a head pipe, and a rear end of the main tube. In a motorcycle where the seat is placed on a seat rail that extends further rearward from the seat, a storage box is placed between the head pipe and the seat, and a fuel tank is placed below the seat, the top surface of the fuel tank is placed along the seat rail. , the lower surface is in line with the front upper part of the rear wheel, and the shape with the lowest part and the thickest vertical width is set in the front half, and the upper and lower halves of the tank, which are divided into upper and lower halves, are seam-welded with flanges at the part near the upper surface. The first half of the upper tank is
It is formed into a tapered step with respect to the lower half tank, and is installed so as to enter from below between the seat rails that match the tapered seat.

(Function) As a result, the fuel tank enters between the seat rails and near the seat bottom plate, increasing its capacity, and the lower part of the seat rail in the front half, where the seat rail becomes narrower, increases in width due to the step. However, since this part has the thickest vertical width, it is expected that a large capacity will be secured. By seam welding the upper and lower halves and the flange portion, the step portion can be easily formed and complex curved shapes can be accommodated.

The injection port is installed on the upper surface of the rear end of the fuel tank that extends rearward from the rear end of the seat, making it easy to fill the fuel tank.It is also stored and locked by an opening/closing lid provided at the rear end of the body cover. The fuel supply cock is also located on the same level as the lower edge of the body cover, making it easy to operate from the side.

(Example) DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to figures.

FIG. 1 is a longitudinal sectional side view of a motorcycle equipped with a fuel tank of the present invention, and FIG. 2 is a plan view showing the frame structure of the motorcycle shown in FIG.

The frame of this two-wheeled motor vehicle includes a pair of left and right main tubes 2 that extend from a head pipe 1 at an angle rearward and downward, and left and right down tubes 3 that hang downward and extend rearward.
The left and right seat rails 5 are formed into an almost inverted trapezoid by the left and right center pillars 4 that connect these rear ends, and are connected to the rear end of the main tube 2 and extend rearward and upward, and the rear end of the main tube 2. The body tube 6 is connected to the seat rail 5 and supports the rear end of the seat rail 5.

An engine unit 7 is suspended within an inverted trapezoidal frame at the center. A front wheel 9 that is steered by a handle 8 is pivotally supported on the head pipe 1, and a rear wheel 11 is supported on the rear end of a swing arm 10 that is pivotally supported on the center pillar 4.

The rear wheel 11 is driven from a drive sprocket gear 13 fixed to the output shaft 12 of the engine unit 7 via a chain 14.

A storage box 15 is arranged from above the main tube 2 to above the front part of the seat rail 5, and a tandem-shaped seat 16 that also serves as a pillion seat is placed on the seat rail 5 behind it.

Due to the presence of the storage box 15, the fuel tank 17 is installed in a space surrounded by the seat rail 5 and the body tube 6 below the seat 16.

Both sides from the front of the engine unit 7 under the storage box 15 are covered with a cowling 18, and continuously below the lower edge of the seat 16 and both sides of the fuel tank 17 are covered with body covers 19.

The main tube 2 is connected to the lower part of the head pipe 1, and extends from a position near the front of the center to the upper part of the head pipe 1.
An upper main tube 2a for reinforcement is provided. Both tubes 2.degree. 2a once expand from the head pipe 1 to both sides and then are led rearward, and narrowly converge from the center of the main tube 2 to the tip of the seat rail 5.

The above-mentioned convergence continues up to the front quarter of the seat rail 5 and the front end of the seat 16, expands gently from there to the center, and extends rearward in a substantially parallel manner in the rear half. The seat rail 16 also has a tapered shape.

Next, as shown in FIG. 3, FIG. 4, and FIG.
1, the rear part is highly sloped, the first half is vertically thick with a lowest part, and the second half is thin.

The fuel tank 17 is a half tank 17 divided into upper and lower halves.
a and 17b are seam-welded at the flange 20 on the mating surfaces. In this case, the upper half case 17a is shallow overall;
The lower half case 17b has a deep shape in the front half.

The upper half tank 17a has a tapered front half in accordance with the above-mentioned tapered shape of the seat rail 5. The lower half tank 17b is not thinner, so in this part, the upper and lower half tanks 17a.

17b is joined by providing a stepped portion with the flange 20 as a boundary (
Figure 5).

This upper half tank 17b is placed so as to penetrate into the seat rail 5, and the upper surface of the flange 20 comes into contact with the lower surface of the seat rail 5 at the front half. The rear end extends rearward from the rear end of the sheet 16 to be at the highest position, and has an injection port 21 on the top surface.
will be installed. There is an opening/closing lid 22 on the rear end surface of the body cover 19, which is opened to supply oil.

The lower bottom of the front half is the lowest part, and the fuel supply cock 2 is located here.
3 is connected.

In this way, the upper part of the fuel tank 17 enters the seat rail 5 and approaches the seat bottom plate, making use of even the slightest dead space to increase capacity, and the front half of the fuel tank 17 has the maximum vertical and horizontal width. You can set a large capacity in this section.

Since the upper and lower halves are separated and seam welded, it is easy to mold complex shapes, easy to form steps, and easy to operate fuel injection. It is effective in maintaining the conventional functions when placed in the

[Effects of the Invention] As described above, in the motorcycle fuel tank device of the present invention, the engine unit is mounted below the main tube extending rearward from the head pipe, and the engine unit is mounted on the seat rail extending further rearward from the rear end of the main tube. In a motorcycle with a seat placed on the seat, a storage box between the head pipe and the seat, and a fuel tank placed below the seat, the fuel tank has an upper surface along the seat rail and a lower surface above the front of the rear wheel. The shape with the lowest part and the thickest vertical width is set in the first half, and the top and bottom two are set in the part near the top.
It is constructed by seam welding the upper and lower halves of the tank with flanges, and the front half of the upper half tank is stepped and tapered with respect to the lower half tank, and the seat rail is designed to fit the tapered seat. It is installed in such a way that it penetrates from below, and the large-capacity fuel tank is easily installed under the seat, reducing the functionality of the fuel system of motorcycles with a storage box placed in the upper center of the vehicle body. It has the effect of preventing

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view of a motorcycle equipped with a fuel tank according to the present invention, FIG. 2 is a plan view showing the frame structure of the motorcycle shown in FIG. 1, and FIG. FIG. 4 is an enlarged side view of the tank, FIG. 4 is an enlarged plan view of the fuel tank of FIG. 1, and FIG. 5 is a sectional view taken along the line AA in FIG. 1...Head pipe, 2...Main tube, 5.
...Seat rail, 7...Engine unit, 9...
・Front wheel, 11...Rear wheel, 15...Storage box, 1
6... Seat, 17... Fuel tank, 17a...
Upper half tank, 17b... Lower half tank, 18... Cowling, 19... Body cover, 20... Flange, 21... Inlet, 22... Opening/closing lid, 23...
・Fuel supply cock.

Claims (1)

[Claims] 1. An engine unit is mounted below a main tube extending rearward from the head pipe, a seat is placed on a seat rail extending further rearward from the rear end of the main tube, and a seat is placed between the head pipe and the seat. For motorcycles with a storage box or fuel tank located below the seat, the fuel tank should be placed so that the top surface is along the seat rail and the bottom surface is along the front upper part of the rear wheel, with the lowest part and vertical width in the front half. The thickest shape is set, and the upper and lower half tanks are divided into upper and lower halves near the top surface, and are seam-welded with flanges. 1. A fuel tank device for a two-wheeled motor vehicle, characterized in that the fuel tank device is formed into a tapered shape and is installed so as to enter from below between seat rails that match the tapered seat. 2. The automatic vehicle according to claim 1, wherein the rear end of the fuel tank extends rearward from the rear end of the seat and is provided with an injection port on its upper surface, and a fuel supply cock is connected to the lowest bottom of the front end.
Fuel tank device for wheeled vehicles.