CN1172050A - Frame structure of small motorbike - Google Patents

Abstract

In the small low-seat motorcycle, the left and right rear frames are supported at the rear end of the main body, and the support position can ensure that the mutual interval between the left and right rear frames (that is, the support span of the rear frame) is relatively long, and the right and left rear frames can be improved. The support rigidity of the seat, and the power head for driving the rear wheels can be close to the front side as a whole while avoiding the interference of the rear frame, and the miniaturization of the front and rear directions of the car body can be achieved. The rear end of the main pipe and the horizontal tube made of steel pipe extending along the left and right direction of the vehicle body are integrated with one end and the other end, and the left and right ends of the horizontal tube are respectively connected to the front ends of the left and right pair of rear frames. .

Description

Frame structure of small motorbike

The present invention relates to the frame structure of small motorcycles. The frame is equipped with: under the pedals where the driver puts his feet, extending along the front and rear direction of the car body, and facing the front head tube, a main pipe stands upright and under the seat, side by side and the front A pair of left and right rear frames connected to the rear ends of the aforementioned main pipes are inclined to the respective front and lower sides, and the rear frames support the vehicle seat.

In the existing above-mentioned motorcycle, a bracket is fixedly provided at the rear end of the main pipe extending in the front-to-back direction under the pedals, and the respective front ends of a pair of left and right rear frames are connected and supported on the bracket. (Example: refer to Shiping Publication No. 1-8478)

Also, in a small motorbike, the hollow portion of the rear frame can be utilized as a passage for cooling air in the transmission mechanism in the power head. There is already a proposal for this case. (Example: refer to Shiping Publication No. 1-8478)

However, in the existing structure disclosed in the aforementioned gazette, the brackets connecting the front ends of the left and right rear frames are relatively small in the vehicle width direction, and the front parts of the left and right rear frames are spaced apart from each other (that is, the span of supporting the rear frame) is relatively small. Short, so the support rigidity for the rear frame seat, etc. is low.

And because the left and right rear frames are close to each other, it is difficult to protrude the front end of the power head driving the rear wheels in this mutual interval, so the power head is made to be close to the front portion of the rear frame (that is, the front side near the vehicle body) It is impossible to miniaturize the vehicle body in the front-rear direction. In addition, especially in the case of connecting the air suction duct protruding from the outer surface of the power head transmission box to the rear frame, the air duct must be relatively long.

In view of such circumstances, the present invention aims to solve the above-mentioned problems in the conventional structure, and to provide a frame structure of a scooter.

In order to achieve the above-mentioned purpose, in the frame structure of the small low-seat motorcycle described in Scheme 1 of the present invention, it is equipped with a pedal under the pedal where the driver puts his feet, extends along the front and rear directions of the car body, and faces the front head tube. An upright main pipe and a pair of left and right rear frames connected to the rear end of the main pipe are arranged side by side under the seat, and the front parts are inclined to the respective front and bottom, and the seat is supported on the rear frame , which is characterized in that the rear end of the aforementioned main pipe and one of the steel horizontal tubes extending in the left and right direction of the car body are connected to the other and combined with each other. The front ends of the racks are respectively connected together. The feature of program 2 of the present invention is that it has the following features in addition to the features of program 1: in the rear end opening of the aforementioned main pipe, the front end of the suspension rod is embedded and supported by buffer rubber, and the suspension rod can swingably support the drive rear wheel. The front of the power head. Furthermore, the feature of the present invention's scheme 3 is that on the basis of the features of scheme 1 or scheme 2, it has the following features: the pair of left and right rear frames are respectively made of hollow tubes, and the front end of the power head for driving the rear wheels protrudes Between the above two rear frames, in order to allow cooling air to be introduced into the transmission case of the power head, the air intake duct protruding from the front outer surface of the same transmission case is at least connected to one side of the aforementioned rear frame. The lower part of the frame is connected, and an air intake that can introduce external air is provided on the upper part of the rear frame.

Fig. 1 is a schematic overall side view of an embodiment of a small motorcycle to which the present invention is applied. Fig. 2 is a simplified plan view of the aforementioned embodiment (the view in the direction of arrow 2 in Fig. 1 ) Fig. 3 is an enlarged view of the section in the direction of arrow 3-3 in Fig. 2 . Fig. 4 is an enlarged view of a section in the direction of arrow 4-4 in Fig. 3 . Fig. 5 is an enlarged view of a section in the direction of arrow 5-5 in Fig. 3 . Fig. 6 is an enlarged view of a section in the direction of arrow 6-6 in Fig. 4 .

The implementation of the present invention will be specifically described below according to the embodiments of the present invention listed in the accompanying drawings.

In the accompanying drawings, Fig. 1 is a simplified overall side view of an embodiment suitable for a small motorbike of the present invention, Fig. 2 is a simplified plan view (view in the direction of arrow 2 in Fig. 1 ) of the aforementioned embodiment, and Fig. 3 is a diagram Figure 4 is an enlarged view of the section in the direction of arrow 3-3 in Figure 2, Figure 4 is an enlarged view of the section in the direction of arrow 4-4 in Figure 3, and Figure 5 is an enlarged view of the section in the direction of arrow 5-5 in Figure 3.

First, in Fig. 1 and Fig. 2, the shell P of the small motorbike V is equipped with: a pedal Ps on which the driver puts his feet, and a front cover that stands up from the front end of the pedal Ps and is integrated with the protective plate. The cover Pf is connected to the rear portion of the pedal Ps and covers the power head 2 for driving the rear wheels and the rear cover Pr of the rear wheel Wr from above. A seat S is provided at the upper end opening of the rear cover. The bottom front end of the seat S is coupled to the rear cover Pr so that it can be opened and closed.

The metal body frame F that supports the aforementioned shell P is integrally integrated with the head pipe H that pivotally supports the front wheel _Wf in a direction-controllable manner in the front cover Pf, and that runs along the vehicle under the pedal Ps. A main pipe 3 extending in the front-rear direction of the body and facing the front head pipe H is located in the rear cover P under the seat S, juxtaposed on the left and right at a certain interval, and the front half is inclined to the front and bottom of each, and is in line with the main pipe. 3 A pair of left and right rear frame 4 ₁ , 4 ₂ connected at the rear end.

A pair of left and right rear frames ₄₁ , ₄₂ are respectively made of hollow tubes, and the upper part, namely the rear half part _4r14r2 , extends in a straight line directly below the seat S along the front-rear direction of the car body, and at the same time leans against each other _. The upper horizontal tubes 5 are combined together, and their rear ends are bent mutually inwardly. From Fig. 5, it can be clearly seen that: at the upper surface of the central position of the left-right direction of the upper cross tube 5, there is an air suction that leads the outside air into the upper cross tube 5 (that is, in the rear vehicle frame ₄₁ ) upwards. At the same time, a trough-shaped support plate 6 is fixed across the suction port 5a. On this support plate 6, a vehicle seat that can abut against the ground and support the middle position of the bottom plate of the vehicle seat S in the front-rear direction is fixed with bolts. Reed tongue strut 7.

On the upper horizontal tube 5, near the support plate 6, a bracket 8 is fixed to the rear and downward. The bottom of the rear half _4r1 , _4r2 of the rear frame ₄₁ , ₄₂ is equipped with _a rear fender _Rf covering the upper part of the rear wheel Wr. The rear cover Pr surrounds the surrounding vehicle body space so that muddy water splashed by the rear wheels Wr does not penetrate.

As shown in Figures 3 and 4, the rear end 3a of the main pipe 3 is integrated with the lower horizontal pipe 10 made of steel pipe extending in the left-right direction of the vehicle body, so that one of them (the main pipe rear end 3a in the figure) penetrates the other (Fig. Shown is horizontal tube 10). The left and right ends of the lower transverse tube 10 are respectively welded to the front ends of a pair of left and right rear frames 4 ₁ , 4 ₂ in a butt welding manner. The lower transverse tube 10 thus constitutes the transverse tube of the present invention. The cross-section of the rear end 3a of the main pipe 3 is a flat ellipse in the up-down direction, and the flat tube passes through the lower horizontal tube 10 in the front-back direction and is welded together with the horizontal tube 10 . Between the front part of the left and right pair of rear frame ₄₁ , ₄₂ and the front of the left and right ends of the lower horizontal tube 10, in order to improve the joint strength between them, a pair of left and right brackets _B1 , _B2 are straddled and welded in between together. The brackets B ₁ and B ₂ are respectively connected to the rear ends of the left and right stays S _t1 and S _t2 that support the footboard Ps.

Between the front parts of the left and right rear frame 4 ₁ , 4 ₂ close to the lower cross tube 10, the front end 2a of the power head (a part of the front cover of the engine E in the figure) protrudes, so that the rear frame 4 ₁ can be avoided , The interference of 4 ₂ can make the power head move forward as a whole at the same time, that is, it is close to the main pipe 3. Therefore, it is possible to reduce the size of the motorcycle in the front-rear direction.

The power head 2 is composed of an engine E and a transmission that changes its speed and transmits it to the rear wheel _Wf , and realizes the function of a rocker arm that pivotally supports the rear wheel Wr in a oscillating manner. The front part of the power head 2 is connected and supported by the lower horizontal tube 10 through the boom 15 so as to be swingable up and down. That is, the support wrist 2b protruding from the lower part near the front end of the power head 2 and the rear frame 15b of the suspender 15 surrounded by a square are rotatably connected together by the rubber sleeve 16 and the fulcrum 17 passing through the rubber sleeve 16. In addition, the front frame 15a of the suspension rod 15 and a pair of brackets _10b , 10b welded together on the left and right rear surfaces of the lower transverse tube 10 and the front parts of the left and right rear frames 4 and 4 are passed through like rubber sleeves. The cylinder 18 and the support shaft 19 penetrating the rubber bush 18 are rotatably connected.

In addition, a groove-shaped stopper piece 15s to which a block-shaped buffer rubber 20 is fixed at the tip protrudes from the front central portion of the front frame 15a of the suspension rod 15 . and combined into one. The stopper piece 15s, as shown in FIG. 6 , is fitted and supported in the opening 3a at the rear end of the main pipe 3 through the buffer rubber 20 . Thereby, when the support shaft 19 of the boom 15 is rotated, the up and down oscillation is elastically suppressed by the buffer rubber 20 . In this way, the brake pad 15 and the buffer rubber 20 are accommodated in the opening of the rear end 3a of the main pipe 3, so the pipe rear end 3a can be used as a swing braking means relative to the boom 15, and the boom support can be achieved. Simplification and miniaturization of construction. In addition, as shown in the figure, the rear end 3a of the main pipe is in a flat cylindrical shape in the vertical direction (that is, relatively long in the left-right direction). Therefore, not only can the support strength for the lower horizontal pipe 10 be increased, but also the suspension can be easily absorbed. The deviation between the left and right positions of the rod 15 and the main pipe rear end 3a. Furthermore, the vibration-proof property of the cushion rubber 20 can be improved.

In addition, one of the left and right sides of the power head is integrated with the transmission case of the flexible transmission M that transmits the engine power to the rear wheels Wr. On the outer surface of the front end of the transmission case 11, a cylindrical cooling air inlet 11a is protruded. Between this intake 11a and the air outlet 4 _a1 that offers on the rear frame ₄₁ lower peripheral wall relative to the other side (the left side of the illustration) of the intake, a flexible suction pipe 12 connected therebetween is interposed. In addition, a suction device (as shown in the figure, a suction fan is fixedly installed on the driving pulley of the transmission mechanism M) is also provided for relying on the suction pipe 12 to forcibly suck cooling air in the transmission case 11 .

Next, the operation of the foregoing embodiment will be described. When the vehicle body V is running, when the rear wheel Wr jumps due to uneven ground and other reasons, the power head 2 is continuously buffered against the rear buffer 9 and shakes up and down around the fulcrum 17 at the rear end of the boom 15 relative to this jump. At this time, due to the impact force applied to the boom 15, the boom 15 will shake to some extent around the fulcrum 19 on one side of the lower horizontal tube 10 (see the two-point line in Fig. 3). The brake pad 15s at the front end is elastically coupled in the opening of the main pipe rear end portion 3a via the buffer rubber 20, so that vibration can be suppressed in a buffered manner.

In addition, along with the operation of the engine E of the power head 2, the suction device 13 in the transmission case 11 operates, and the suction device 13 operates from the vehicle body space directly below the seat S through the suction port 5a and the upper horizontal pipe. 5 inside, the same direction of the rear frame 4 ₁ inside, the air outlet 4 _a1 and the suction pipe 12, the external air is introduced into the transmission box 11 to cool the transmission mechanism M, and then through the exhaust air installed at the appropriate position on the power head 2 The air port (not shown) is exhausted to the outside.

Also, the front portions of the left and right rear frames 4 ₁ , 4 ₂ are supported by the rear end 3 a of the main pipe 3 by the lower cross pipe 10 made of steel pipes perpendicular to the pipe 3 . Since the distance between the left and right rear frames 4 ₁ and 4 ₂ of the support portion (that is, the support span of the rear frame) can be ensured to be relatively long, it is possible to effectively reduce the weight of the frame structure and reduce the cost. The supporting rigidity of the seat S of the left and right rear frames, the rear outer cover Pr, the rear shock absorber 9, and the like is greatly improved. And because left and right rear frame 4 ₁ , the anterior portion of 4 ₂ intervals expand, and the front end 2a of the power head 2 that drives rear wheel can not be reluctantly protruded in its interval, and this power head 2 can avoid contact with the rear frame. The interference of 4 ₁ and 4 ₂ is close to the front side as a whole.

In addition, as shown in the figure, by protruding the front end 2a of the power head 2 into the space between the front ends of the left and right rear frames 4 ₁ , 4 ₂ , the air intake pipe 12 protruding from the outer surface of the transmission case 11 of the power head 2 can be made Close to the bottom of the rear frame 4 ₁ , 4 ₂ , therefore, the tube length can be shortened correspondingly, and the fresh external air from the upper part of the rear frame 4 ₁ , 4 ₂ to the duct 12 through the inside of the rear frame can be efficiently into the gearbox.

The embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various embodiments are possible within the scope of the present invention. For example: the aforementioned embodiment is a small two-wheeled motorcycle, but the present invention can also be implemented in a small three-wheeled motorcycle. Also, in the foregoing embodiment, the air intake 5a that should be provided on the rear frame 4 ₁ , 4 ₂ indicates that the opening is opened on the upper surface of the upper horizontal tube 5 connecting the left and right rear frame 4 ₁ , 4 ₂ and is placed on the vehicle. The underside of the seat spring tongue stay. But the position of the air intake of the present invention is not limited to the foregoing embodiments, for example, any position on the top of the rear frame 4 ₁ , 4 ₂ can directly open the air intake. However, in order to avoid the intrusion of muddy water and rainwater brought up by the jumping of the rear wheels, and to allow only fresh outside air to be taken in from the intake port, it is desirable that the car body space directly below the seat S surrounded by the rear cover cover Inhalation port is opened upwards.

Also, in the foregoing embodiment, the rear end 3a of the main pipe passes through the horizontal pipe 10 at its front and back, but it is also possible to make the horizontal pipe 10 pass through at its left and right with respect to the main pipe rear end 3a on the contrary.

Through the invention of each of the above schemes: the front end of the left and right rear frames is supported on the rear end of the main tube by a relatively light, cheap, and high-bending steel tube made of steel pipes, so the distance between the left and right rear frames of the supporting parts ( The support span of the rear frame) can be set long enough. In this way, weight reduction and cost reduction of the frame structure can be achieved. At the same time, it can also effectively improve the support rigidity of the left and right rear frames to the seat. Moreover, by enlarging the mutual spacing between the front parts of the left and right rear frames, the front end of the power head driving the rear wheels can be made to face the front part, avoiding the interference of the rear frame, and can be as close as possible to the front end at the same time. direction miniaturization.

In addition, especially according to the invention of claim 2, the front end of the suspension rod for the power head and the buffer rubber are accommodated in the opening at the rear end of the main pipe, and the main pipe itself can be used as a braking means for the suspension rod. The support structure of the boom is simplified and miniaturized.

Also according to the invention of scheme 3, the front end of the power head driving the rear wheel can be made to protrude in the mutual interval of the left and right rear vehicle frame front parts, so the power head can be made closer to the front side of the car body. And the duct that protrudes on the outer surface of the power head transmission case is used for air suction can be close to the bottom of the rear frame, so the length of the duct can be shortened, so that from the top of the rear frame, through the rear frame The fresh outside air entering the duct can be efficiently introduced into the transmission box.

Claims (3)

1. the present invention relates to the body frame structure for automotive of small low saddle motorcycle, it comprises: put at chaufeur pin pedal below along the car body fore-and-aft direction extend, and the person in charge (3) that erects facing to preceding size pipe (H); About below-seat side by side and anterior to separately tiltedly below tilt, with the aforementioned person in charge's (3) rear end (3a) bonded assembly pair of right and left after vehicle frame (4 ₁, 4 ₂); This back vehicle frame (4 ₁, 4 ₂) on can support vehicle seat (S), it is characterized in that: the aforementioned person in charge's (3) rear end (3a) is combined into one vehicle frame (4 after the two ends, the left and right sides of aforementioned transverse tube (10) are connecting pair of right and left respectively with the transverse tube of the steel pipe system of extending along the car body left and right directions with the form that a side connects the opposing party ₁, 4 ₂) front end.

2. the chassis structure of the small low saddle motorcycle of putting down in writing as claim 1, it is characterized by: embed the front end (15s) of supporting suspension rod (15) by yielding rubber (20) in the opening of the rear end of the aforementioned person in charge (3) (3a), this suspension rod (15) can joltily support to drive the front portion of the unit head (2) of trailing wheel.

3. as the chassis structure of claim 1 or 2 small low saddle motorcycles of being put down in writing, it is characterized by: vehicle frame (4 after the aforementioned pair of right and left ₁, 4 ₂) make by hollow tube respectively, simultaneously, the front end (2a) that drives the unit head (2) of the trailing wheel vehicle frame (4 after above-mentioned two of advancing by leaps and bounds ₁, 4 ₂) between, import for the air that will cool off usefulness in the transmission gearbox (15) of this unit head (2), will from the outstanding intake guide (12) of the forward outer surface of transmission gearbox (15) at least with a side aforementioned back vehicle frame (4 ₁, 4 ₂) the bottom connect, and at back vehicle frame (4 ₁, 4 ₂) top the air suctiton inlet (5a) can import extraneous air is set.

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