JPH1016859A - Motorcycle frame structure - Google Patents

Abstract

(57) [Problem] To provide a frame structure of a motorcycle capable of forming a low-cost and high-accuracy body frame without requiring high dimensional accuracy for a main pipe and a sub-pipe and without a special processing step. SOLUTION: In a motorcycle in which an internal combustion engine is suspended below a single main pipe 4 and a pair of left and right sub pipes 6 and 8 are connected to a rear portion of the main pipe 4 to form a body frame 2, the sub pipe 6 , 8 are rectangular pipes, and plates 5 and 7 having flat surfaces are welded to the rear side surface of the main pipe 4, and the front portions of the sub pipes 6 and 8 are welded to the flat surfaces of the plates 5 and 7. The frame structure of a motorcycle constituting the body frame 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motorcycle frame structure.

[0002]

2. Description of the Related Art There are various types of motorcycle frame structures. In a body frame of a type in which one main pipe extends rearward from a head pipe, a seat rail or the like is provided behind the one main pipe. The sub-pipe is configured so that its front portion is connected and extends rearward.

[0003] When a sub-pipe is connected to the main pipe, a method of hitting the sub-pipe against the main pipe and welding it together is generally used. An example in which the main pipe is a square pipe and the sub-frame is a cylindrical pipe.
Japanese Patent Application Laid-Open No. 39350/1999 proposes a joining method in which a flat surface is formed by flat pressing the front end of a cylindrical sub-frame, and the flat surface is brought into contact with a side surface of a main pipe and welded.

[0004]

According to the former method, in which the sub-pipe is abutted against the main pipe, the dimensional accuracy of the main pipe and the sub-pipe must be increased in order to maintain the assembling accuracy, resulting in an increase in cost.

In the latter method of contacting the processed front end of the sub-frame with the side surface of the main pipe, the front end of the sub-pipe is flat-pressed, although it is adjustable for assembly and does not require high dimensional accuracy for the main pipe and the sub-pipe. The manufacturing process is added, and the cost increases accordingly.

The present invention has been made in view of the above points, and an object thereof is to provide a low-cost, high-precision body frame which does not require high dimensional accuracy for the main pipe and the sub-pipe and does not require any special processing step. It provides a motorcycle frame structure that can be configured.

[0007]

In order to achieve the above object, the present invention has an internal combustion engine suspended under one main pipe, and a pair of left and right sub-pipes connected to the rear of the main pipe. In the motorcycle constituting the vehicle body frame, the sub-pipe is a square pipe in section, a plate having a flat surface is welded to a rear side surface of the main pipe, and a front portion of the sub-pipe is welded to the flat surface of the plate. As a result, a frame structure of a motorcycle constituting a body frame is obtained.

[0008] Since the front part of the sub pipe of the square pipe is welded to the flat surface of the plate welded to the rear side surface of the main pipe, errors at the time of joining can be absorbed, and the dimensional accuracy of the main pipe and the sub pipe is reduced. High precision is not required, and processing of the pipe is not required, so that the manufacturing process can be simplified and the cost can be reduced.

The motorcycle has a frame structure for a motorcycle according to claim 1, wherein the plate is a hanger plate for supporting an internal combustion engine, and it is necessary to prepare a special plate only for connecting the main pipe and the sub pipe. Therefore, the structure can be simplified and the cost can be reduced.

The main pipe has a frame structure for a motorcycle according to claim 1 or 2, and is applicable to a cylindrical main pipe.

[0011] An attachment stay integrally provided with an upper and lower fastening portion is protruded forward from a head pipe formed at the front end of the main pipe, and a front cover and a front basket are sequentially stacked on the attachment stay. By adopting the motorcycle frame structure according to claim 1, the front basket can be easily mounted as an option, and the mounting of the front basket is not greatly affected by frame accuracy. The number of parts can be reduced.

The motorcycle frame structure according to claim 1, wherein a tool box integrated with a battery case is provided below the fuel tank supported by the sub-pipe.
The tool is stored in a tool box separate from the accessory case, ensuring the capacity of the accessory case, enabling the integration of heavy objects such as batteries and tools, lowering the center of gravity, and reducing the number of parts. Can be planned.

[0013] The frame structure of the motorcycle according to claim 5, wherein a driver for attaching and detaching the cover is arranged under the seat separately from the tools stored in the tool box, so that the capacity of the accessory compartment can be secured. As well as
The cover and the like of the tool box can be attached and detached by the driver for attaching and detaching the cover arranged under the seat, and the maintainability is not impaired.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall side view of a motorcycle 1 according to the present embodiment, and FIG. 2 is a side view of a body frame 2 of the motorcycle 1.

The vehicle body frame 2 has one cylindrical main pipe 4 extending obliquely downward from the head pipe 3 at the front of the vehicle body, and is welded slightly rearward in the middle of the main pipe 4. The front ends of the left and right seat rails 6, 6 are welded via a pair of front engine hanger plates 5, 5, respectively, and extend rearward diagonally upward.

The back stays 8, 8 are respectively provided between a pair of left and right rear engine hanger plates 7, 7 welded to the rear end of the main pipe 4 and portions slightly forward of the rear ends of the seat rails 6, 6. Is interposed. The seat rail 6 and the back stay 8 are pipes having a square cross section.

The head pipe 3 and the main pipe 4 are reinforced with a gusset 9 and connected to each other.
The first cross plate 10 and the second cross bar between the 6
11, the third cross plate 12 is erected and reinforced sequentially.

An internal combustion engine 15 is suspended between a front engine hanger plate 5 and a rear engine hanger plate 7 below the main pipe 4 in such a body frame 2, and is supported by a front head pipe 3 of the body frame 2. A steering wheel 17 is provided on the upper part of the steering shaft, which is extended left and right, and a front wheel 19 is pivotally supported at a lower end of a front fork 18 which is connected to a lower part and extends downward.

The rear engine hanger plate 7 includes:
The rear end of the rear fork 20 is supported at the rear end of the rear fork 20 extending rearward by swinging up and down. Right and left rear cushions 23 are interposed between the rear end of the rear fork 20 and the seat rail 6.

The internal combustion engine 15 has a crankcase 15a attached to the front and rear engine hanger plates 5 and 7 by supporting pins.
The cylinder 15b is suspended from the crankcase 15a forward to near the horizontal from the crankcase 15a. Above the cylinder 15b, a carburetor is inserted via an intake pipe 25.
An air cleaner 27 is further provided thereon and supported by the main pipe 4. An exhaust pipe 28 extends from the lower portion of the cylinder 15b, extends rearward along the lower surface of the crankcase 15a, and is connected to a muffler 29 on the right side of the rear wheel while deflecting rightward.

On the other hand, on the seat rail 6, a fuel tank 30 is located in the front half supported by the first cross plate 10, and a small case 31 is disposed behind the fuel tank 30. The fuel tank 30 and the small case A seat 32 whose front end is pivotally mounted and swingably opens and closes covers the top of the seat 31. A box member 33 integrally formed with a battery box 34 and a tool box 35 is provided below the fuel tank 30 in a space formed by the main pipe 4, the seat rail 6, and the back stay 8 to form a triangle in a side view. Mating supported battery 36 and tool 37
Is to be accommodated.

In the motorcycle 1, a front top cover 40 covers the front of the head pipe 3, and a main pipe cover 41 covers an upper side of the main pipe 4 from the rear side of the head pipe 3. Between the main pipe cover 41 and the cylinder 15b of the internal combustion engine 15.
A pair of left and right front side covers 42, 42 that cover the upper part of the vehicle and the intake system such as the carburetor 26 and the air cleaner 27 from the left and right, and a pair of left and right leg seals 43, 43 that extend to the left and right and cover the front of the driver's feet are provided. ing.

Side covers 44 cover the left and right sides of the box member 33, respectively, and a rear cover 45 is provided below the seat 32 so as to cover the periphery of the fuel tank 30 and the accessory case 31. A front fender 46 covers the upper part of the front wheel 19, and a rear fender 47 covers the rear wheel 22 from above to the rear. A front basket 48 is attached in front of the front top cover 40.

The connection structure of the body frame 2 of the motorcycle 1 having the above-described structure will be described below. Referring to FIG. 5 to FIG. 8, the front engine hanger plate 5 welded to the main pipe 4 has a fitting curved portion 5a fitted to the cylindrical main pipe 4 and is displaced outward from a rear portion thereof and downwardly. And a mounting hole 5c for suspending a mount of the internal combustion engine 15 by a support pin 16a below the hanger 5b.

The central portion of the fitting curved portion 5a is slightly depressed outward to form a vertical flat surface 5d. When this front engine hanger plate 5 is welded by fitting the fitting curved portion 5a to the cylindrical main pipe 4 from the side,
A flat surface 5d is vertically provided on the outer surface of the fitting curved portion 5a, and a hanger portion 5b is vertically provided at a position deviated outward (see FIG. 8). The front engine hanger plate 5 is provided on the left and right sides of the main pipe 4 as targets.

The rear engine hanger plate 7 is
Referring to FIGS. 5, 6, 9 and 10, downwardly at a position deviated outward through a fitting curved portion 7a fitted to cylindrical main pipe 4 and a horizontal step portion 7b at the lower end thereof. The hanger part 7c is hanging.

A vertical flat surface 7d is formed in the upper part of the hanger part 7c, and a mounting hole 7e for supporting the rear mount of the internal combustion engine 15 by the support pin 16b is formed near the center of the front end edge of the hanger part 7c. And the flat surface 7d
A pivot hole 7f through which the pivot shaft 21 for pivotally supporting the rear fork 20 is supported is formed along the lower part of the shaft, and a pivot hole 7g for pivotally supporting the main stand 39 is formed vertically below the pivot hole 7f. (See FIG. 6).

This rear engine hanger plate 7
A curved portion 7 is fitted to the rear of the cylindrical main pipe 4 from the side.
When a is fitted and welded, the flat surface 7d extends vertically downward from the position deviated outwardly, and the mounting hole 7e, the pivot hole 7f, and the pivot hole 7g are located on the hanger portion 7c which hangs down. . Note that the rear engine hanger plate 7
It is provided on the right and left rear part of the main pipe 4.

In this manner, the front and rear engine hanger plates 5 and 7 are welded to the main pipe 4. At the front half of the body frame 2, a mounting piece 51 is provided on the lower front surface of the head pipe 3 so as to protrude forward. The gusset 9 is provided with cover brackets 52, 52 on the left and right sides, respectively, and the front engine hanger plates 5, 5 are also provided with cover brackets 53, 53 on the left and right sides.

On the other hand, a seat rail 6 and a back stay 8 are welded to the rear half of the body frame 2 on the left and right, respectively, and a first cross plate 10 and a second
The cross bar 11 and the third cross plate 12 are sequentially connected. The second crossbar 11 is installed between the left and right columns 11a, 11a having a triangular shape, and the columns 11a, 11a are welded to the left and right seat rails 6, 6, to form the columns 11a, 11a.
Are provided with support shafts 11b, 11b protruding outward, and the upper ends of the rear cushions 23, 23 are pivotally mounted on the support shafts 11b, 11b, respectively.

After the front half and the rear half of the body frame 2 are separately assembled as described above, the main pipe 4 of the front half, the seat rail 6 of the rear half, and the back stay 8 are connected to each other.
They are connected via front and rear engine hanger plates 5 and 7.

That is, the front end of the seat rail 6 abuts against the outer flat surface 5d of the front engine hanger plate 5 fixed to the main pipe 4 from outside (FIGS. 2, 7 and 7).
At the same time, an outer flat surface 7d of the rear engine hanger plate 7 fixed to the rear portion of the main pipe 4 is formed.
Then, the front end of the back stay 8 abuts from the outside (see FIGS. 2, 9 and 10).

At this time, the mounting position can be adjusted, and the dimensional error of the front and rear members can be absorbed. The front engine hanger plate 5 and the front end of the seat rail 6 are welded to each other when the front half and the rear half of the body frame 2 have an appropriate positional relationship with each other, and the rear engine hanger plate 7 and the back stay 8 with the front end,
Join together.

As described above, the dimensional error can be absorbed when the vehicle body frame is connected.
The seat rails 6 and the back stays 8 do not require high dimensional accuracy and are easy to manufacture, and there is no need to apply special processing to the seat rails 6 and the back stays 8, thereby simplifying the manufacturing process and reducing costs. Can be achieved.

Further, the front and rear engine hanger plates 5 and 7 interposed between the front half main pipe 4 and the rear half seat rails 6 and back stays 8 use plates for suspending the internal combustion engine 15. In addition, since the rear engine hanger plate 7 also serves as a pivot bearing for pivotally supporting the rear fork 20, the number of parts is small, the structure is simplified, and the cost can be further reduced.

A mounting piece 51 protrudes from the head pipe 3 at the front end of the body frame 2 thus assembled, and a mounting stay 55 is fixed to the mounting piece 51. As shown in FIG. 11, the mounting stay 55 has a connecting piece 55b protruding from the rear surface of the main body plate 55a with the front facing obliquely upward and forward, and the mounting piece 51 and the connecting piece 55b are bolted at two front and rear locations. Has been fixed.

On the main body plate 55a of the mounting stay 55, a screw hole 55c for fastening is formed at the center of the upper part, and screw holes 55d, 55d for fastening are formed at the lower left and right sides, respectively. The front top cover 40 is overlaid on the front surface of the main body plate 55a of the mounting stay 55, and the front basket 48 is mounted via a collar 56.

The front top cover 40 is a slightly symmetrical plate member which is slightly curved as shown in FIGS. 12 and 13 so as to cover the front of the head pipe 3, and has one mounting hole 40a at the center thereof and a lower portion thereof. Mounting holes 40 on each side
The three mounting holes 40a, 40b, and 40b correspond to the three fastening screw holes 55c, 55d, and 55d of the mounting stay 55, respectively. . The front basket 48 is attached to the rear wall 48a by the mounting stay.
Three mounting brackets 49 are fixedly attached to the three fastening screw holes 55c, 55d, 55d, respectively.

When attaching the front basket 48,
First, the front top cover 40 is mounted on the front surface of the main body plate 55a of the mounting stay 55, and the screw holes 55c, 55d, 55d and the mounting holes 40 are provided.
a, 40b, and 40b, and then overlap each other.
The front basket 48 is placed in the recesses a, 40b and 40b with the cylindrical collar 56 interposed therebetween, and the mounting bracket 49 of the wall 48a is abutted against each collar 56 so as to overlap with each other. Through the mounting bracket 49, the collar 56, and the mounting holes 40a, 40b, and 40b, respectively.
Screw 55c, 55d, 55d and tighten (see FIG. 11).

In the mounting stay 55 for fastening the front basket 48 together with the front top cover 40, the upper screw hole 55c for fastening and the lower screw holes 55d, 55d are integrally formed. The mounting position and orientation of the frame are not affected by the accuracy of the frame, and high accuracy is not required for the frame. The front basket 48 is fastened to the mounting stay 55 together with the front top cover 40, so that the number of parts can be reduced.

When the front basket 48 is not mounted, only the front top cover 40 may be fastened to the mounting stay 55 with screws 57, and the front basket 48 can be an optional accessory.

The mounting stay 55 for mounting the front basket 48 is bolted to a separate mounting piece 51 protruding from the head pipe 3, but as shown in FIG. The mounting piece 60a protruding from the rear surface of the head pipe 60a may be directly welded to the head pipe 3. In the modification shown in FIG. 18, the same members as those in the above embodiment, such as the front basket 48 and the front top cover 40, use the same reference numerals.

The box member 33, which is fitted and supported in a substantially triangular space in a side view formed by the main pipe 4, the seat rail 6, and the back stay 8, substantially at the center of the body frame 2, as described above. A box 34 and a tool box 35 are integrally formed, and a right triangular right wall 33a as shown in FIG. 14 (a right side view of the box member 33) and FIG. The battery box 34 is formed to protrude to the left,
A tool box 35 is formed on the front side of the tool box 35 so as to have a substantially square rectangular shape and be recessed leftward.

Accordingly, both the battery box 34 and the tool box 35 have openings on the right side, and four mounting holes 33b provided on the peripheral edge of the right side wall 33a are screwed to mounting brackets provided on the vehicle body frame 2. The box member 33 is fixed. A cover member 38 is attached to the right side wall 33a so as to close both openings of the battery box 34 and the tool box 35. On the right side wall 33a of the box member 33, a screw hole 33c for attaching the cover member 38 is formed at an upper part, a locking hole 33d which is a vertically long hole is formed at a front part, and a pivot holding piece 33e is formed at a lower part. .

As shown in FIGS. 16 and 17, one lid member 38 has a shape that simultaneously closes a vertically long rectangular opening of the battery box 34 and a square opening of the tool box 35.
A mounting hole 38a is provided corresponding to the screw hole 33c of the right side wall 33a of the box member 33, and a locking piece 38b is formed so as to protrude corresponding to the locking hole 33d, and is pivotally supported corresponding to the pivot holding piece 33e. A shaft 38c is formed. A locking claw is formed at the tip of the locking piece 38b.

The pivotally holding piece 33 below the box member 33
The pivot shaft 38c of the lid member 38 is fitted into the e, and the lid member 38 is pivotally mounted so as to be swingable about the lower pivot shaft 38c. Then, the lid member 38 is swung and applied to the right side surface of the box member 33, and the locking piece 38b is inserted and locked in the locking hole 33d in the front part of the right side wall 33a, thereby locking the battery box 34 and the tool box 35. And a screw is passed through and screwed into a mounting hole 38a corresponding to the screw hole 33c on the upper part, and fixed. Conversely, when opening the lid member 38,
The operation reverse to the above may be performed, and the opening and closing of the lid member 38 can be easily performed.

The tool 37 to be stored in the tool box 35
In addition, only the driver 58 is held by the holder 59 formed on the bottom plate 32a of the seat 32 (see FIG. 1). Therefore, at the time of maintenance, the seat 32 is opened upward, the driver 58 is taken out, and the right side cover 44 is removed.
The tool 37 can be taken out of the tool box 35 by loosening the mounting screws of the above, removing the side cover 44, and then loosening the screws of the cover member 38 and opening the cover member 38.

Thus, the maintainability is good. In addition, since the tool box 35 is provided separately from the accessory case 31, the capacity of the accessory case 31 below the seat can be sufficiently secured.

Since the tool box 35 and the battery box 34 are integrally formed, the weight of the battery 36 and the tool 37 can be concentrated, and the box member 33
Is disposed below the fuel tank 30, so that the heavy objects of the battery 36 and the tool 37 are arranged at relatively low positions on the vehicle body to reduce the center of gravity. Since the tool box 35 and the battery box 34 are integrally formed as the box member 33, the number of parts can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall side view of a motorcycle according to an embodiment of the present invention.

FIG. 2 is a side view of a body frame of the motorcycle.

FIG. 3 is a plan view of the same.

FIG. 4 is a rear view of the same.

FIG. 5 is an exploded perspective view of the vehicle body frame.

FIG. 6 is an exploded side view showing one process of assembling the vehicle body frame.

FIG. 7 is a top view of the front engine hanger plate (FIG. 6);
FIG.

FIG. 8 is a front view of the same (viewed in the direction of arrow VIII in FIG. 6).

FIG. 9 is a top view of the rear engine hanger plate (FIG. 6);
FIG.

FIG. 10 is a rear view of the same (viewed in the direction of arrow X in FIG. 6).

FIG. 11 is a side view of a main part with a part of a cross section showing a mounting structure of the front basket omitted.

FIG. 12 is a front view of the front top cover.

FIG. 13 is a side view of the same section.

FIG. 14 is a right side view of the box member.

FIG. 15 is a top view of the same.

FIG. 16 is a right side view of the lid member.

FIG. 17 is a top view of the same.

FIG. 18 is a side view of a main part of a modification of the front basket mounting structure, with a partial cross-section partially omitted.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Body frame, 3 ... Head pipe, 4 ... Main pipe, 5 ... Front engine hanger plate, 6 ... Seat rail, 7 ... Rear engine hanger plate, 8 ... Back stay, 9 ... Gusset, 10 ... first cross plate, 11 ... second cross bar, 12 ... third cross plate, 15 ... internal combustion engine, 17 ... handle, 18 ... front fork, 19 ... front wheel, 20 ... rear fork, 21 ... pivot shaft, 22 ... Rear wheel, 23 ... rear cushion, 25 ... intake pipe, 26 ...
Vaporizer, 27… Air cleaner, 28… Exhaust pipe, 29… Muffler, 30… Fuel tank, 31… Accessories, 32… Seat, 33…
Box member, 34 ... battery box, 35 ... tool box, 36 ... battery, 37 ... tool, 38 ... lid member, 39 ... main stand, 40 ... front top cover, 41 ... main pipe cover, 42 ... front side cover, 43 ... leg shield, 44 ... side cover, 45 ... rear cover, 46 ... front fender, 47 ... rear fender, 48 ... front basket, 49 ... mounting bracket, 51 ... mounting piece, 52, 53 ... cover bracket, 55 ... mounting stay, 56… Color, 57… Screw, 58… Driver, 59… Holder, 60… Mounting stay.

Claims (6)

[Claims] 1. A motorcycle in which an internal combustion engine is suspended below a single main pipe and a pair of left and right sub-pipes are connected to a rear portion of the main pipe to form a body frame. A frame structure for a motorcycle, wherein a plate having a flat surface is welded to a rear side surface of the main pipe, and a front portion of the sub-pipe is welded to a flat surface of the plate to form a body frame. 2. The motorcycle frame structure according to claim 1, wherein said plate is a hanger plate for supporting an internal combustion engine. 3. The motorcycle frame structure according to claim 1, wherein the main pipe is a cylindrical pipe. 4. A head pipe formed at the front end of the main pipe, a mounting stay integrally having an upper and lower fastening portion is protruded forward, and a front cover and a front basket are sequentially stacked on the mounting stay, The motorcycle frame structure according to claim 1, wherein the motorcycle is fastened together at a fastening portion. 5. The motorcycle frame structure according to claim 1, wherein a tool box integrated with a battery case is provided below the fuel tank supported by the sub-pipe. 6. The motorcycle frame structure according to claim 5, wherein a driver for attaching and detaching a cover is arranged below the seat separately from the tools stored in the tool box.