JP2003072648A - Car body frame for motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily install a rear frame 25 onto a front frame 23. SOLUTION: This car body frame is provided with a front frame 23 having a tank rail 21 and a rear arm bracket 22, and a rear frame 25 detachably installed on a rear end part of the front frame 23. A connection part between the front frame 23 and the rear frame 25 comprises an engagement recess 51 formed in the front frame 23, and an engagement protrusion 52 on the rear frame 25 to be engaged with the engagement recess 51. By engaging the engagement protrusion 52 with the engagement recess 51, a front end part of the rear frame 25 is supported by the front frame 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motorcycle body frame having a front frame and a rear frame detachably attached thereto.

[0002]

2. Description of the Related Art Conventionally, a vehicle body frame of a motorcycle having a relatively large engine displacement has a structure in which a pair of left and right tank rails are connected to a head pipe and a rear arm bracket is connected to a rear end portion of the tank rail. I am collecting.
In this type of vehicle body frame, the tank rail supports the fuel tank and the front part of the engine, and the rear arm bracket supports the rear arm and the rear part of the engine. Further, a seat is supported by a front frame formed by the tank rail and the rear arm bracket in the vehicle body frame via a rear frame.

The rear frame is formed so as to extend rearward of the vehicle body from the front frame, and is detachably attached to the front frame with attachment bolts. The reason why the rear frame is detachably attached to the front frame in this way is mainly to facilitate the work when painting the vehicle body frame. That is, by painting the front frame with the rear frame detached from the front frame, the space required for painting may be smaller than in the case where both frames are integrally formed.

[0004]

However, the vehicle body frame formed by dividing the front frame and the rear frame as described above has a problem that the work of attaching the rear frame to the front frame becomes complicated. . this is,
This is because it is necessary to simultaneously perform the work of determining the mounting position by aligning the front end of the rear frame with the front frame and the work of tightening the fixing bolt.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a motorcycle body frame in which the rear frame can be easily attached to the front frame.

[0006]

In order to achieve this object, a motorcycle body frame according to the present invention includes a front frame having a tank rail and a rear arm bracket, and a removable front frame. The rear frame is attached to the front frame and the rear frame, and the connecting portion between the front frame and the rear frame is an engaging concave portion formed in one frame and an engaging convex portion of the other frame engaged in the engaging concave portion. And a front end portion of the rear frame is supported by the front frame by engaging the engagement convex portion with the engagement concave portion.

According to the present invention, since the front end of the rear frame can be temporarily held by the front frame, the work of determining the mounting position of the rear frame and the work of tightening the fixing bolt can be performed separately. it can.

A motorcycle body frame according to a second aspect of the present invention is the motorcycle body frame according to the first aspect of the invention, wherein the engaging concave portion and the engaging convex portion are both outside the vehicle in the frame. It is a part formed on the exposed surface to the exterior. According to the present invention, the outer shape of the engaging concave portion and the engaging convex portion in the engaged state is more complicated than that in which the matching shape at the exposed portion is formed by a straight line, and therefore the front frame and the rear frame are Even if there is a deviation in the connection portion with the, this becomes less noticeable.

A motorcycle body frame according to a third aspect of the present invention is the motorcycle body frame according to the second aspect, wherein the front frame and the rear frame have axes extending in the vehicle width direction. The left and right bolts are joined together, and the two bolts on one side are arranged in a substantially vertical direction, and the upper bolts are located on the inner side in the vehicle width direction than the lower bolts in the tightened state. It is a thing. According to the present invention, the width of the seat located above the connecting portion between the front frame and the rear frame can be narrowed.

A motorcycle body frame according to a fourth aspect of the present invention is the motorcycle body frame according to the first aspect of the invention, wherein the front frame and the rear frame have axes extending in the vehicle width direction. The bolts are coupled to each other, and the coupling portion has a bolt-penetrating boss formed in the front frame and a bolt-penetrating boss formed in the rear frame, and the boss of the front frame is the boss of the rear frame. Both bosses are connected to each other by the bolts that are located on the outer side in the vehicle width direction and are inserted from the vehicle outer side direction. According to the present invention, during the bolt insertion work, even if the rear frame is moved to search the bolt holes of the temporarily placed rear frame, the state where the rear frame is inserted into the bolt penetration boss of the front frame The bolt does not move.

A motorcycle body frame according to a fifth aspect of the present invention is the motorcycle body frame according to the first aspect, wherein the tank rail is formed so as to extend rearward and downward. The rear arm bracket is formed so as to extend substantially vertically, and the connecting portion between the front frame and the rear frame is provided in the vicinity of the bent portion from the tank rail to the rear arm bracket. According to the present invention, since the connecting portion of the front frame with the rear frame does not largely project rearward from the bent portion, the handleability becomes good in the manufacturing process of the front frame alone.

A motorcycle body frame according to a sixth aspect of the present invention is the motorcycle body frame according to the fifth aspect, wherein a pair of left and right frames are connected to a bent portion of the front frame. In addition, a cross member having a support portion for the upper end of the rear wheel suspension device is provided, and the rear frame is provided with an attachment portion for covers that form the rear portion of the vehicle body. According to this invention, the support rigidity of the vehicle body frame can be improved by the cross member. The position (dimension) accuracy of the connection portion of the front frame with the rear frame is increased. Further, since the entire rear wheel suspension device including the rear wheel and the rear arm can be assembled to the front frame without the rear frame, workability is improved. Since the covers constituting the rear part of the vehicle body can be sub-assembled with the rear frame, workability is further improved.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a motorcycle body frame according to the present invention will be described in detail below with reference to FIGS. FIG. 1 is a side view of a motorcycle employing a vehicle body frame according to the present invention, FIG. 2 is a plan view of the same, and FIG.
4 is an enlarged side view showing a main part, FIG. 4 is a side view showing a foaming agent filling range in the rear arm bracket, and FIG. 5 is a sectional view taken along line VV of the rear arm bracket in FIG. Figure 6
Is a front view showing the rear arm bracket as seen from the front side of the vehicle body, FIG. 7 is a plan view of the rear frame, FIG. 8 is a side view of the front part of the rear frame, and FIG. 9 is a view of the front frame and the rear frame in FIG. It is the IX-IX sectional view taken on the line of a connection part.

In these figures, the reference numeral 1 designates a motorcycle according to this embodiment. The motorcycle 1 is of a so-called on-road type, and includes a cowling 4 that covers a head pipe portion 3 of a vehicle body frame 2 according to the present invention. 1, reference numeral 5 indicates a front wheel, 6 a front fork, 7 a steering wheel, 8 a fuel tank, 9 a seat, 10 an engine, 11 a rear wheel,
Reference numeral 12 is a rear arm, and 13 is a footrest. The engine 10 is a water-cooled 4-cycle engine, which is supported by a vehicle body frame 2 described later, and drives a rear wheel 11 by a chain 14.

The vehicle body frame 2 includes a front frame 23 including a pair of left and right tank rails 21 extending rearward and downward from a head pipe (not shown), and a rear arm bracket 22 welded to the rear ends of the tank rails 21.
And a fixing bolt 24 on the rear arm bracket 22.
And the rear frame 25 fixed by. The material of each frame member forming the vehicle body frame 2 is an aluminum alloy.

The tank rail 21 is formed of a pipe having a rectangular cross section, as shown in FIG. 1, is formed so as to be inclined downward and rearward in a side view, and a rear end portion thereof is connected to a rear arm bracket 22. is doing. Further, as shown in FIG. 1, the tank rail 21 has a sub pipe 26, which is L-shaped in a side view, welded to a lower portion thereof, and supports the cylinder 10 a of the engine 10 via the sub pipe 26. Further, the tank rail 21 supports the fuel tank 8 via a bracket (not shown).

The rear arm bracket 22 is shown in FIGS.
As shown in FIG. 6, a hollow rear arm bracket main body 27 forming a pair in the vehicle width direction and cross pipes 28, 28 connecting the upper and lower ends of the left and right rear arm bracket main bodies 27 are integrally formed. However, it is formed so as to extend substantially vertically in a side view. The rear arm bracket body 27 and the upper and lower cross pipes 28, 28 are integrally formed by casting. As shown in FIG. 1, the rear arm bracket main body 27 supports the rear arm 12 via a pivot shaft 29 so as to be swingable in the vertical direction,
The upper bracket 27a welded to the upper end supports the rear end of the fuel tank 8 and the front end of the seat 9.
As shown in FIGS. 3 and 6, the upper cross pipe 28 of the two cross pipes 28, 28 has a cushion bracket 30 projecting rearward of the vehicle body at the center portion in the left-right direction. The upper end of a rear cushion unit 31 (see FIG. 1) is supported by 30. The lower end of the rear cushion unit 31 has the link 3
It is connected to the rear arm 12 via 2.

Further, the rear arm bracket 22 has bolts 33, 34 for fixing the rear portion of the engine 10 (see FIG. 1).
The inside of the engine 10 is filled with a vibration isolator 35 (see FIG. 5) so that noise generated by transmitting the vibration of the engine 10 to a wide side surface is minimized. The bolt holes of the rear arm bracket 22 through which the engine fixing bolts 33, 34 are inserted are shown in FIGS.
The range indicated by reference numeral 36 in FIG.
Shown with hatching inside.

In the present embodiment, the vibration isolator 35 is a foam resin foamed in the rear arm bracket 22. This anti-vibration material 35 is attached to the rear arm bracket 22.
In order to fill the inside, an injection port 37 (see FIG. 5) is formed in the cross pipe 28, and the foamed resin is injected from the injection port 37 to foam in the rear arm bracket 22. This rear arm bracket 22
As shown in FIGS. 4 and 5, the cross pipe 28 is connected to the substantially central portion of the rear bracket body 27 in the front-rear direction, and the space in the rear bracket body 27 is separated from the connecting portion with the cross pipe 28. Since it is formed so that it becomes gradually narrower as
It is possible to fill the left and right rear arm bracket bodies 27, 27 with the foamed resin substantially evenly. This is because as the foamed resin moves inside the rear bracket body 27 while foaming, the resistance when the foamed resin flows gradually increases, and the foamed resin flows toward the side where the resistance is relatively small. The inlet 37 is formed in a portion of the upper cross pipe 28 on the left side of the vehicle body with respect to the center portion in the left-right direction where the cushion bracket 30 is located. This is to prevent the rigidity of the central portion of the cross pipe 28 that receives the cushion reaction force from being reduced by the inlet 37.

The rear frame 25 is shown in FIGS.
As shown in FIG. 5, a pair of left and right rear frame bodies 41, 41 supported by the rear arm bracket body 27, a pair of left and right pipes 42, 42 inserted into the rear end portions of the rear frame bodies 41, 41 and welded, First cross member 43 for connecting the rear frame bodies 41 to each other
A second cross member 44 for connecting the rear end portions of the pipe 42, a sheet receiving member 45 extending horizontally between the front end portions of the pipe 42, and the like. The rear frame body 41 is formed into a hollow shape by casting. As shown in FIG. 1, the rear frame 25 supports a seat 9, a side cover 46 that laterally covers the rear part of the seat 9, a grab bar 47, a tail lamp 48, a fender 49, a flasher lamp 50, and the like. I am letting you.

As shown in FIG. 1, the connecting portion between the rear frame 25 and the front frame 23 is provided in the vicinity of the bent portion from the tank rail 21 to the rear arm bracket 22. More specifically, as shown in FIGS. 3 and 7 to 9, this connecting portion is an engaging recess 51 that is open toward the rear of the vehicle body on both sides of the rear end portion of the rear arm bracket 22 in the vehicle width direction. And engaging protrusions 52 that project toward the front of the vehicle body and engage with the engaging recesses 51 on both sides in the vehicle width direction at the front end of the rear frame 25, respectively. By engaging the engaging convex portion 52 with the mating concave portion 51, the rear frame 25
The front end of the above is supported by the front frame 23. The engaging concave portion 51 and the engaging convex portion 52 respectively form engaging surfaces extending in the vehicle width direction at portions facing each other, and the engaging convex portion 52 is formed on the engaging surface of the engaging concave portion 51 in the engaged state. The engagement surfaces make contact. The engagement surface of the engagement protrusion 52 is indicated by reference numeral 5 in FIG.
2a.

As shown in FIGS. 4 and 8 and 9, the front frame 23 and the rear frame 25 are fixed to each other by projecting them at the rear end of the rear arm bracket 22 and on the upper and lower sides of the engaging recess 51, respectively. The outer boss 53 and the inner boss 54 projecting from the front end of the rear frame body 41 on both the upper and lower sides of the engaging projection 52 are connected by the fixing bolts 24 whose axes extend in the vehicle width direction. By doing, we are going to four places. The fixing bolt 24 is
These bosses 53, 54 are inserted from the vehicle outer side direction. The outer boss 53 and the inner boss 54 constitute a boss for bolt penetration according to the present invention. Of the four fixing parts, two fixing parts on one side in the vehicle width direction have two fixing parts.
The fixing bolts 24, 24 of the book are arranged substantially in the vertical direction, and the upper fixing bolt 24 is positioned on the inner side in the vehicle width direction than the lower fixing bolt 24 in the fastening state.

Further, the bosses 53 and 54 are arranged such that the outer boss 53 is in a state where the engaging projection 52 is engaged with the engaging recess 51.
Inner bosses 54 are lined up inside the vehicle body, and bolt holes 53a, 54a formed in these bosses 53, 54 in a side view.
Are formed so as to substantially overlap with each other. The bolt hole of the outer boss 53 is a through hole, but the bolt hole of the inner boss 54 is formed with a female screw, and the fixing bolt 24 in the engaged state described above.
The bolts 53 can be inserted into the bolt holes 53a of the outer boss 53 from the outside of the vehicle body and turned, so that both bosses can be fastened together by the fixing bolts 24.

Body frame 2 constructed as described above
First, the front frame 23 and the rear frame 25 are painted respectively, and after the parts are assembled after painting, the two frames are connected to each other. That is, the front frame 23 and the rear frame 25 are separately coated, and the front frame 23 is coated with the engine 10, the front fork 6 and the rear arm 1.
2 etc. are assembled and the rear frame 25
Attach the seat 9, side cover 42, tail lamp 44, etc.

After assembling the main parts of at least the rear side portion of the front frame 23, the engaging projection 52 at the front end of the rear frame 25 is engaged with the engaging recess 5 of the rear arm bracket 22.
Engage 1 from the rear of the vehicle. By this engagement, the front end portion of the rear frame 25 is supported by the front frame 23. As described above, the front frame 23 and the rear frame 2
By assembling the parts before attaching 5, the assembling work can be performed in a state where the upper part of the rear part of the front frame 23 is wide open. That is, the rear arm 12
It is possible to improve the workability of the work of assembling the rear cushion unit 31, etc.

By temporarily holding the front end portion of the rear frame 25 on the front frame 23 in this way, the operator supports the rear frame 25 with one hand so as not to drop it from the front frame 23, while It is possible to insert the fixing bolt 24 into the boss 53 of the front frame 23 by hand and tighten the fixing bolt 24. Therefore, the body frame 2 can perform the work of determining the mounting position of the rear frame 25 and the work of tightening the fixing bolts 24 separately from each other, so that the work can be performed at the same time as compared with the conventional one. Easy to assemble.

In the above-described embodiment, the front frame 2
Although the example in which the engagement concave portion 51 is formed in 3 is shown, the engagement concave portion 51 may be formed in the rear frame 25 and the engagement convex portion 52 may be formed in the front frame 23.

Further, as compared with the case where the fitting shape at the exposed portion at the connecting portion between the front frame and the rear frame is constituted by a straight line, the external shape of the engaging concave portion 51 and the engaging convex portion 52 in the engaged state. Is complicated, so the front frame 2
Even if there is a deviation in the connection portion between the rear frame 3 and the rear frame 25, this will be inconspicuous. Therefore, even if the shapes and dimensions of the engaging concave portions 51 and the engaging convex portions 52 are slightly changed due to manufacturing errors or the like, it is possible to manufacture a motorcycle body frame whose appearance is not impaired.

Further, the front frame 23 and the rear frame 25 are connected by two left and right fixing bolts 24 having an axis extending in the vehicle width direction, and the two bolts 24, 24 on one side are substantially vertically moved. In the fastened state, the upper bolts 24 are located on the inner side in the vehicle width direction compared to the lower bolts 24, so that the width of the seat 9 located above the connecting portion between the front frame 23 and the rear frame 25 is aligned. Can be narrowed. Therefore, it is possible to improve the foot contact of the occupant seated on the seat 9.

Furthermore, the front frame 23 and the rear frame 25 are connected by a fixing bolt 24 whose axis extends in the vehicle width direction.
3 has a boss 53 for bolt penetration formed in 3 and a boss 54 for bolt penetration formed in the rear frame 25, and the boss 53 of the front frame 23 is outside the boss 54 of the rear frame 25 in the vehicle width direction. Located on the bosses 53, 5 by means of the fixing bolt 24 which is inserted from the vehicle outer side direction.
Since 4 are connected, even if the rear frame 25 is moved to search the bolt holes 54a of the temporarily placed rear frame 25 during the bolt insertion work, the boss 53 for bolt penetration of the front frame 23 The fixing bolt 24, which is inserted in, does not move. Therefore, the bolt insertion work can be easily performed.

In addition, the tank rail 21 is formed so as to extend rearward and downward, and the rear arm bracket 22 is formed so as to extend substantially vertically.
And the rear frame 25 are connected to the tank rail 21.
It is provided in the vicinity of the bent portion from the rear arm bracket 22 to the rear arm bracket 22. According to this invention,
Since the connecting portion of the front frame with the rear frame does not largely project rearward from the bent portion, the handleability becomes good in the manufacturing process of the front frame alone.

The front frame 23 can be improved in support rigidity by the cross member 28 provided on the rear arm bracket 22, and the position (dimension) accuracy of the connecting portion of the front frame 23 with the rear frame 25 can be improved. Get higher Further, since the entire rear wheel suspension device including the rear wheel 11 and the rear arm 12 can be assembled to the front frame 23 without the rear frame 25, workability is improved. Since the covers constituting the rear part of the vehicle body can be sub-assembled with respect to the rear frame 25, workability is further improved. Therefore, it is possible to manufacture the vehicle body frame 2 which has high strength and accuracy and is easy to assemble parts.

[0033]

As described above, according to the present invention, the front end portion of the rear frame can be temporarily held by the front frame by engaging the engagement convex portion with the engagement concave portion. The work of determining the mounting position of the frame and the work of tightening the fixing bolt can be performed separately.
Therefore, since the rear frame can be easily attached to the front frame, it is possible to provide a vehicle body frame for a motorcycle 1 which is easy to assemble even though the front frame and the rear frame are formed separately. You can

According to the second aspect of the present invention, the outer shape of the engaging concave portion and the engaging convex portion in the engaged state becomes complicated as compared with the case where the fitting shape at the exposed portion is constituted by a straight line. Even if the connecting portion between the front frame and the rear frame is misaligned, this is less noticeable. Therefore,
It is possible to provide a vehicle body frame for a motorcycle in which the external appearance is not impaired even if the shapes and dimensions of the engaging concave portions and the engaging convex portions are slightly changed due to manufacturing errors or the like.

According to the third aspect of the invention, the width of the seat located above the connecting portion between the front frame and the rear frame can be narrowed, so that the occupant seated on the seat is improved in foot contact. Can be made.

According to the invention described in claim 4, during the bolt insertion work, even if the rear frame is moved to search for the bolt hole of the temporarily placed rear frame, the bolt boss of the front frame is penetrated. Since the bolt that is inserted into the shaft does not move, the insertion work can be easily performed.

According to the fifth aspect of the present invention, since the connecting portion of the front frame with the rear frame does not largely project rearward from the bent portion, the front frame alone is manufactured in a manufacturing process (for example, a coating process). Good handling.

According to the sixth aspect of the invention, the supporting rigidity of the vehicle body frame can be improved by the cross member. The position (dimension) accuracy of the connection portion of the front frame with the rear frame is increased. Further, since the entire rear wheel suspension device including the rear wheel and the rear arm can be assembled to the front frame without the rear frame, workability is improved. Since the covers constituting the rear part of the vehicle body can be sub-assembled with the rear frame, workability is further improved. Therefore, it is possible to provide a motorcycle body frame that has high strength and accuracy and is easy to assemble parts.

[Brief description of drawings]

FIG. 1 is a side view of a motorcycle that employs a vehicle body frame according to the present invention.

FIG. 2 is a plan view of a motorcycle that employs a vehicle body frame according to the present invention.

FIG. 3 is a side view showing an enlarged main part.

FIG. 4 is a side view showing a foaming agent filling range in a rear arm bracket.

5 is a sectional view taken along line VV of the rear arm bracket in FIG.

FIG. 6 is a front view showing a state in which a rear arm bracket is viewed from the front side of the vehicle body.

FIG. 7 is a plan view of a rear frame.

FIG. 8 is a side view of the front part of the rear frame.

9 is a sectional view taken along the line IX-IX of the connecting portion between the front frame and the rear frame in FIG.

[Explanation of symbols]

2 ... Body frame, 21 ... Tank rail, 22 ... Rear arm bracket, 23 ... Front frame, 25 ... Rear frame, 51 ... Engagement concave part, 52 ... Engagement convex part.

Claims (6)

[Claims] 1. A front frame having a tank rail and a rear arm bracket, and a rear frame detachably attached to a rear end of the front frame,
The connecting portion between the front frame and the rear frame has an engaging concave portion formed in one frame and an engaging convex portion of the other frame engaged with the engaging concave portion, and is engaged with the engaging concave portion. A vehicle body frame for a motorcycle, wherein a front end portion of a rear frame is supported by the front frame by engaging the fitting convex portions. 2. The motorcycle body frame according to claim 1, wherein the engaging concave portion and the engaging convex portion are both formed on a vehicle outer side portion of the frame and exposed to the exterior. flame. 3. The motorcycle body frame according to claim 2, wherein the front frame and the rear frame are joined by two right and left bolts whose axes extend in the vehicle width direction, and two bolts on one side are A motorcycle body frame having a structure in which the bolts on the upper side are arranged in the vehicle width direction in comparison with the bolts on the lower side when they are fastened in a substantially vertical direction. 4. The motorcycle body frame according to claim 1, wherein the front frame and the rear frame are joined by a bolt having an axis extending in the vehicle width direction, and the joining portion is formed by a bolt penetrating member formed on the front frame. Boss for
Having a boss for bolt penetration formed on the rear frame,
A motorcycle body frame in which the boss of the front frame is located outside the boss of the rear frame in the vehicle width direction, and both bosses are joined by the bolt that is inserted from the vehicle outside direction. 5. The motorcycle body frame according to claim 1, wherein the tank rail is formed so as to extend rearward and the rear arm bracket is formed so as to extend substantially vertically, and the front frame and the rear frame are provided. The body frame for a motorcycle, which is provided in the vicinity of a portion where the tank rail and the rear arm bracket are bent, is connected to the vehicle body frame. 6. The motorcycle body frame according to claim 5, wherein a cross member having a support portion for the upper end of the rear wheel suspension is provided in the bent portion of the front frame, the pair of left and right frames being connected to each other. A vehicle body frame for a motorcycle, wherein the rear frame is provided with mounting portions for covers that form the rear portion of the vehicle body.