JPS6036986B2 - Motorcycle frame structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a frame structure suitable for motorcycles, particularly small motorcycles.

More specifically, a main pipe is extended diagonally rearward and downward from the bottom of the head tube, and the rear end of this main pipe is connected to two vertical main pipes arranged diagonally above and below on the left and right, and the head Two subtubes are extended rearward from the top of the tube approximately horizontally, and the rear ends of the left and right subtubes are tied to the upper ends of the left and right vertical main pipes mentioned above, and the tube is extended rearward between these tied parts. The extended article storage box is installed across the board and the joints are connected, and this storage box forms a cross member for the left and right subtubes and the left and right vertical pipes to ensure their strength, and the left and right subtubes In between, a fuel tank is arranged so that its rear end faces the joint, and the above-mentioned article storage box and fuel tank are covered with a sheet, which simplifies the frame, increases its strength, and also makes it relatively large. The present invention relates to a frame structure for a motorcycle in which bulky parts are arranged centrally in a concentrated manner, and the parts are arranged within the width of the frame, thereby streamlining the arrangement of parts and improving the appearance.

A small motorcycle has a frame made of thick pipe material, on which a seat holder, electrical equipment storage box, fuel tank, engine, etc. are arranged.

The frame to which these parts are assembled is composed of, for example, a horizontal frame, a vertical frame, reinforcing members between them, etc. Therefore, the pipes that serve as the frame material inevitably have a large diameter, and the weight of the frame becomes large. The width of the power unit, which includes the seat holder, electrical equipment storage box, fuel tank, and engine, is wider than the frame, so the parts protrude from the sides of the frame, which is unfavorable for appearance.In addition, the width of each part Since the frame is wider than the frame, the mounting bracket is also large, and the shape and structure are complicated, which poses problems in terms of installation.Furthermore, since the width of the above parts is wider than the frame, the space of the frame can be utilized. However, rational arrangement such as concentrated arrangement within this width is not possible.In view of the above-mentioned problems with the frame of a small motorcycle, the inventors have requested to simplify the frame, increase its strength, and improve the number of parts. A rational and centralized arrangement should be planned.
This is what constitutes the present invention. The purpose of the present invention is to
Extend the main pipe rearward from the bottom of the head tube,
The rear end of this is tied to the bottom of two vertical pipes installed vertically on the left and right, and the two subtubes are extended rearward from the top left and right of the head tube almost horizontally, and each of the subtubes is Connect the rear end and the upper end of each of the vertical pipes, respectively,
An article storage box that also serves as a seat support is erected and extended rearward across the joints to connect the joints, and a fuel tank is suspended between the subtubes in front of the storage box. To provide a frame structure for a motorcycle in which the tank and article storage box are covered with a sheet.

Therefore, an object of the present invention is to use an article storage box as a cross member at the joint between two vertical members and two horizontal members to improve strength without requiring a separate cross member. To provide a frame structure for a motorcycle, which can save parts, eliminate the use of silk as a backing material, and simplify and reduce the weight of the frame.

Further, the object of the present invention is to place an article storage box that also serves as a cross member behind the connecting part of the above-mentioned members, and in front of this, a fuel tank is arranged between the lower surfaces of the subtubes, and a sheet is covered from above. Therefore, parts with a relatively large volume can be concentrated in the upper center of the vehicle body, and can be arranged within the width of the frame, making it possible to rationally arrange parts and improve appearance, as well as improve the overall appearance. To provide a frame structure of a motorcycle capable of supporting the weight including the weight of an occupant in a box part forming a mounting part and a cross member, and achieving reliable support while simplifying and reducing the weight of the frame.

Furthermore, it is an object of the present invention that the subtube and the vertical pipe are made into two pieces so that the frame has a width and a space, so that the above-mentioned parts can be stored and arranged within this space, and the engine can also be operated at the bottom of the frame. It can be arranged within the width, therefore, the engine and other parts mentioned above can be easily and reliably installed and supported with simple brackets and installation, and each part can be supported and arranged easily and rationally. Provided is a frame structure that can simplify the entire motorcycle and improve its appearance.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is a side view of the motorcycle, Figure 2 is a perspective view of the front of the frame viewed from diagonally below, and Figure 3 is the upper part of the frame.
FIG. 4 shows an enlarged perspective view of the rear part, and FIG. 4 shows a perspective view of the main part of the frame as seen diagonally from the front.

Reference numeral 1 denotes a head tube that supports the steering shaft with an iron frame, and a rearward extending portion la is provided at the middle or lower part of the head tube, and a main pipe 2 extends diagonally rearward and downward from the extending portion la.
has been extended.

The rear end of the main pipe 2 has vertical pipes 3 and 4 arranged diagonally up and down, spaced apart from each other left and right, and parallel to each other.
It is connected to the vertical pipe side by being tied to a cross plate 5 installed across the middle to lower part of the pipe so as to connect the middle part to the lower part of the pipe.

A step bar 6 is installed across the lower ends of the left and right vertical pipes 3 and 4, and both ends of the step bar 6 are extended to the outside of the pipes 3 and 4, and a step bar 7 is attached to the extended part. has been done. On the other hand, the front ends of two sub-tubes 8 and 9 are connected to the upper left and right sides of the head tube 1 by welding or the like.
The front end portions 8a, 9a of the sub tubes 8, 9 are bent so as to bulge outward, and extend rearward in parallel and horizontally with the same width as the pipes 3, 4 described above.

The rear ends 8b and 9b of the sub tubes 8 and 9 are bent diagonally rearward and downward, and the rear ends of each rear part are connected to the vertical pipes 3 and 4 described above.
8b and 9b are joined to 4, respectively. The joining member IQ, 11 of each of the above members is at least approximately reverse L
It forms a T-shape in the illustration, and has a cylindrical part 1 at the front and lower part.
They are formed by press molding or the like to form 0a, 10b, 11a, and 11b.

The rear ends of the subtubes 8 and 9 are bonded by formation welding to the cylindrical parts 10a and 11a that protrude forward at the top, and the upper ends of the vertical pipes 3 and 4 are attached to the downward cylindrical parts 10b and 11b. The joint ends of the left and right subtubes and vertical pipes are joined by welding, etc. Extension pieces 10c and 11c are provided at the rear of the joint sections 10 and 11, between which an article storage box 12 which also serves as a sheet support with only the top open is erected across, and left and right portions 12a and 12a of the box 12 are extended. Pieces 10c, 11
Attach by welding etc. to c. In this way, the left and right members 8, 3 and 9, 4 are connected using the article storage box 12 as a cross member.

A bar 13 is installed transversely between the front parts of the box 12, and the upper ends of the rear cushion knits 14 are connected. As is clear from FIG. 2, each of the subtubes 8 and 9 has a cross member 15 installed across its front end and front portion to increase strength in the width direction, and is covered with a cover (not shown). Cover the supported harness. A fuel tank 16 is disposed in front of the article storage box 12 between the left and right subtubes 8 and 9.

The rear end of the fuel tank 16 is located in front of the box 12, and the rear end is locked to the bar 13 with a locking part 16b or the like.
The front or middle portion is located at the rear of the cross member 15 constructed between the rear portions of the subtuffs 8 and 9 15a.
is combined with The width of the fuel tank 16 is approximately equal to the outer width of the subtubes 8 and 9, and recessed steps 16a and 16a are provided on the left and right sides of the upper part in the width direction, and the upper part is inserted between the tubes 8 and 9, as shown in FIG. It was shown to. A sheet 17 is provided so as to cover most of the fuel tank 16 on and in front of the article storage box 12 except for the front part.

The front part of the seat 17 is jointed to the intermediate part of the fuel tank 16 and the cross member 15a at joints 16a and 17a with rubber or the like interposed therebetween, and the seat 17 is commonly connected to the subtube side, and the seat 17 has a hinge at the front end. The rear upper surface of the tank 16 and the storage box 12
It is constructed so that the top surface can be opened. This is shown in Figure 7. This serves as a barrier between refueling from the tank refueling port 16c and the storage box 12. Electrical components such as a battery, turn signal relay, and ignition coil (not shown) are stored in the storage box 12. shall be. As described above, the sheet 17 covers the storage box 12 and the fuel tank 16 located below it and provided in the space between the subtubes 8 and 9 and the vertical pipes 3 and 4.

Furthermore, in the illustrated embodiment, the rear carrier 18 extends rearwardly.
The front ends of the left and right stays 18a are tied to both ends of the bar 13, and a turn signal light 19 and a tail light 20 are tied to the rear of the rear carrier 18.

Further, an engine hanger bracket 21 is provided rearward at the bottom of each of the left and right vertical pipes 3, 4, to which, for example, the rear part of the engine 22a of a unit swing type power unit 22 is pivotally connected, and a transmission case extending to the rear of the engine 22a is attached. 2
The upper part of 2b is connected to the lower end of the 1'' cushion knit 14 to form a unit swing type suspension mechanism.

This case 22b supports the rear wheel 23, and
A front fork 24 extends below the head tube 1 to support a front wheel 25, and a handle 26 is provided above. As is clear from the above, according to the present invention, two vertical pipes and two subtubes extending rearward from the top of the head tube are connected at their corresponding ends,
This part is connected to a cross member with an article storage box that also serves as a seat support that extends rearward.
It is possible to connect the two without requiring a separate cross member between the connecting parts, increase the strength, obtain the practically necessary and sufficient strength, simplify the frame with the minimum number of structural members,
Vertical pipes and subtubes can also be made with small dents, and in relation to the main pipe, a structure similar to a truss structure with approximately triangular sides can be obtained, making it lightweight and simple as a motorcycle frame. Provides strength.

In particular, since there is a space between two subtubes and two vertical pipes, the above-mentioned storage items are arranged within the width of the space, and a fuel tank is installed in front of this box, and the fuel tank is placed between the subtubes and above the vertical pipes. The tank and storage box are placed centrally at the top of the frame and covered with a sheet from above, allowing for a large volume and allowing the entire passenger seat area to be placed within the width of the frame. It is possible to rationalize the arrangement and improve the appearance.

In addition, since the present invention has a frame having a space with two vertical pipes and two subtubes as described above, parts other than the above parts, that is, the power unit, these accessory parts,
All of the parts such as the rear unit can be placed within this width, so the above parts can be attached with simple brackets and support structures without the need for brackets with wide and complicated shapes and structures. In addition to being able to achieve a rational and visually pleasing component arrangement, the above frame structure, brackets, etc.
This simplifies assembly, which is a major factor in contributing to mass production of small motorcycles and cost reduction.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a schematic side view of a motorcycle, Fig. 2 is a perspective view of the front part of the frame as seen diagonally from below, and Fig. 3 is a portion including an article storage box. Fig. 4 is a perspective view of the rear part of the frame, Fig. 5 is a side view of the main parts with the seat and fuel tank attached, Fig. 6 is a sectional view taken along line 5-6, Fig. 7 The figure is an explanatory side sectional view of the joint between the seat and the tank. In the drawing, 1 is the head tube, 2 is the main pipe, 3,
4 is vertical village, 8 and 9 are horizontal village, 12 is goods storage box, 16
is the fuel tank. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1. Extend the main pipe rearward from the lower part of the head tube, tie the rear ends of this to the lower parts of two vertical members provided on the left and right, and in the vertical direction, and connect the two main pipes from the left and right of the upper part of the head tube to the rear. Extending the horizontal member rearward approximately horizontally,
Each rear end of the horizontal member and the upper end of the vertical member are tied together, an article storage box is erected and extended rearward so as to cross between the tied parts, and the tied parts are connected. A frame structure for a motorcycle, characterized in that a fuel tank is disposed between the horizontal members in front of the box, and the tank and the storage box are covered with a sheet.