JP3106399B2 - Motorcycle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motorcycle provided with an engine having an intake port on the rear side and a cylinder inclined forward.

[Conventional technology]

Conventionally, as a method of lowering the center of gravity of motorcycles and concentrating the mass, the cylinder of the engine is tilted forward, and the carburetor is turned upward to the intake pipe extending upward from the intake port provided on the rear side of the cylinder. There is one in which an air cleaner connected to a mounting and carburetor is disposed above a cylinder, and a fuel tank is disposed between the cylinder and the carburetor and a seat supported above the vehicle body (for example, Japanese Patent Application Laid-Open No. 60-1985). 185684
Reference).

In the conventional motorcycle described above, a main frame for supporting an engine is extended obliquely forward of a cylinder from a rear arm support portion to a position above a cylinder, and a head pipe provided at a front end of the main frame is provided with a front fork extending upward from the front wheel. The upper end is supported.

[Problems to be solved by the invention]

However, in the conventional motorcycle configured as described above, a front fork extending upward, and a head pipe part that is particularly strongly reinforced and supports the front fork are present at a high position above the cylinder, and the fuel tank is ,
Normally, it extends forward from the lower part of the seat to the middle part of the main frame and is supported by the left and right seat rails at high positions, so it is difficult to achieve a low center of gravity and centralized mass. .

In addition, the seat of the motorcycle has a structure in which the front portion is formed to have a width smaller than that of the rear portion so that the seat can be easily seated. Is formed so that the width dimension of the first portion becomes small. For this reason, when the fuel tank is shaped so as to pass downward through the narrow portion of the seat rail, the tank width below this portion is further reduced, causing a reduction in the tank capacity. It was difficult to lower.

[Means for solving the problem]

The motorcycle according to the present invention has an engine in which a cylinder leans forward supported on left and right main frames, and a rear arm supporting a rear wheel is swingably supported on a lower rear portion of the main frame. A carburetor is attached to an intake pipe extending obliquely rearward and upward from an intake port provided on the side so that the intake port is directed upward, and an air cleaner is connected to the intake port so as to be disposed above the cylinder. In a motorcycle in which a fuel tank is disposed between the cylinder and the carburetor and a seat on an upper part of the vehicle body, the left and right main frames are moved from a rear arm support portion below a seat front portion to a front upper side to a cylinder side. Extend,
A steering device connects the sub-frame provided at the front end to the front of the main frame, and a knuckle that supports the front wheels rotatably at the front of the vehicle body and a rear end that supports the vehicle body side to swing up and down A front wheel suspension device having a lower arm and an upper arm whose front end is operably supported on the knuckle is provided, the steering device and the knuckle are connected by a connecting member, and the air cleaner is connected to the intake pipe of the carburetor from the suction port of the carburetor. It extends obliquely upward and rearward at an angle less than the gradient, forms the bottom wall of this air cleaner in a planar shape, and forms a suction portion that opens rearward on the top wall of the air cleaner, and connects the fuel tank to the main frame. Support, with the lower part of this fuel tank facing between the left and right main frames, and the lower surface It is close to the upper surface of the scan, and causes along in close proximity to the bottom wall of the air cleaner on the upper surface of the fuel tank, in which are approximated to the front end top of the fuel tank to the carburetor bottom.

(Operation)

The main frame and the front wheel suspension device can be disposed at a low position, and the subframe and the steering device can be reduced in weight because no force is applied from the front wheels. The fuel tank is supported by a main frame at a low position, and the center of gravity of the tank is positioned near a transmission case of the engine.

In addition, the left and right main frames have a certain width in the vehicle width direction because they require strength to support the engine and torsional rigidity. This width is wider than the portion corresponding to the front part of the seat of the seat rail which has conventionally supported the fuel tank. Therefore, even if the lower portion of the fuel tank is arranged between the left and right main frames, the tank capacity does not decrease. Moreover, since the main frame is disposed at a lower position and the fuel tank is disposed between the cylinder and the seat, the fuel tank is supported as compared with a case where the fuel tank is disposed above the cylinder. The bracket does not need to protrude upward from the main frame.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. 1 and FIG.

FIG. 1 is a side view showing a motorcycle according to the present invention, and FIG.
The drawings are plan views showing a schematic configuration of the front wheel suspension device. In these drawings, 1 indicates a frame. The frame 1 includes left and right main frames 1a for supporting the engine 2, the seat 3, and the like, and a sub-frame 1b rotatably connected to a front portion of the main frame 1a. This sub-frame 1b has a steering shaft 1c rotatably supporting a steering device 4 composed of a steering wheel, a brake lever and the like provided at a front end, and is connected to the main frame 1a by a driving device (not shown). The steering device 4 is configured to be able to change its height by being rotated about the connecting portion.

The engine 2 includes a crankcase 2a integrally provided with a transmission case M and a cylinder 2b having an intake port on the rear side, and the cylinder 2b is inclined toward the front side of the vehicle body.

Numeral 5 is a front wheel suspension device for suspending the front wheel 6 so as to be steerable. The knuckle 5a rotatably supports the front wheel 6,
A lower arm 5b, an upper arm 5c, and the like are supported at the front end so as to be steerable at the front end, and the rear end is swingably supported by the engine 2 up and down. A front cushion (not shown) is interposed between the lower arm 5b and the engine 2.

Reference numeral 7 denotes a hydraulic cylinder for steering.
The main body is fixed to the lower arm 5b, and an advance / retreat rod is connected to the knuckle 5a, and is connected to a control device (not shown) that controls the hydraulic pressure according to the turning operation of the steering device 4. That is, the hydraulic cylinder 7
And the like are connecting members for connecting the steering device 4 and the knuckle 5a. The hydraulic cylinder 7 is driven by rotating the steering device 4, whereby the front wheels 6 are steered.

A rear arm 8 rotatably supports a rear wheel 9. The rear arm 8 is swingably supported by a rear arm supporting portion 1d of the main frame 1a via a pivot shaft 10. The rear arm 8 and the main frame A rear cushion unit 11 is interposed between the front cushion unit 1a and the rear cushion unit 11a. The left and right main frames 1a extend from the rear arm support portion 1d below the seat front portion 3a to the front upper side to the side of the cylinder 2b.

Reference numeral 12 denotes a carburetor, which is connected to the engine 2 through an intake pipe 13 extending obliquely upward and rearward from the intake port of the engine 2.

Numeral 14 denotes an air cleaner, which extends obliquely rearward and upward from the suction port of the carburetor 12 at an angle smaller than the gradient of the intake pipe 13 and is connected to the carburetor 12 via a joint 14a. It is supported by the frame 1.
The air cleaner 14 has a built-in air cleaner element 14b, and a suction portion of the upper wall is provided with a silencer 14c opened rearward.
Further, the bottom wall of the air cleaner 14 is formed in a planar shape.

Reference numeral 15 denotes a fuel tank, which is disposed between the left and right main frames 1a and between the air cleaner 14 and the transmission case M of the engine 2.
It is supported by the main frame 1a. The lower portion of the fuel tank 15 faces between the left and right main frames 1a, and the lower surface is close to the upper surface of the transmission case M of the engine. Further, the upper surface of the fuel tank 15 is brought close to and along the bottom wall of the air cleaner 14,
The upper end of the front end of the fuel tank 15 is
Close to a.

A fuel supply pump (not shown), such as an electromagnetic pump, is connected to a fuel supply pipe (not shown) for supplying fuel from the fuel tank 15 to the carburetor 12, and the fuel is supplied to the carburetor by the fuel supply pump. It is configured to be supplied to 12. Reference numeral 16 denotes a fuel supply pipe for replenishing the fuel tank 15 with fuel. The fuel supply pipe 16 projects from the fuel tank 15 so as to face a fuel supply section provided at the front of the seat 3.

Reference numeral 17 denotes a radiator. As shown in FIG. 2, two radiators 17 are disposed in front of the engine 2 on the left and right sides, and are attached to the cylinder 2b of the engine 2 via an upper bracket 17a and a lower bracket 17b. . Incidentally, 18 is a radiator cover for guiding the traveling wind to the radiator 17,
19 is a front cowl.

In the motorcycle configured as described above, the main frame 1a supporting the engine 2 is disposed at a low position, and the front wheel suspension device 5 is a swing arm type and disposed at a low position. Further, since the sub-frame 1b connected to the front portion of the main frame 1a and the steering device 4 provided on the sub-frame 1b do not receive any force from the front wheels 6, the weight can be reduced. Moreover, the fuel tank 15 is supported by the main frame 1a at a low position, and the lower portion of the fuel tank 15 is disposed between the left and right main frames 1a and close to the upper surface of the transmission case M. Therefore, the center of gravity of the tank can be located at a position close to the transmission case M.

Therefore, the heavy members can be prevented from being located at a high position, and the heavy members can be arranged so as to be concentrated around the engine. It can be aimed at.

In addition, the left and right main frames 1a have a certain width in the vehicle width direction because they require strength to support the engine 2 and torsional rigidity. This width is wider than the portion corresponding to the front part of the seat of the seat rail which has conventionally supported the fuel tank. For this reason, even if the lower portion of the fuel tank 15 is disposed between the left and right main frames 1a, the tank capacity does not decrease. In addition, the main frame 1a is disposed at a lower position, and the fuel tank 15 is attached to the cylinder 2b and the seat 3.
The fuel tank 15 is located between the cylinder 2b
Fuel tank compared to a structure that is placed above
Since the bracket for supporting the fuel tank 15 does not need to project upward from the main frame 1a, the fuel tank 15 can be firmly supported.

Further, an intake pipe 13 extends obliquely upward and rearward from an intake port provided on the rear side of the cylinder, and an air cleaner 14 communicating with the intake pipe 13 via a carburetor 12 is connected to the intake pipe 13 through the intake port of the carburetor 12. Since the bottom wall of the air cleaner 14 is formed flat and the suction wall opening rearward is formed in the upper wall of the air cleaner 14, the suction pipe 13 Both the air cleaner 14 and the air cleaner 14 are tilted rearward and upward, so that the bending of the intake passage from the inside of the air cleaner 14 to the intake port of the engine can be reduced, the intake resistance is reduced, and the charging efficiency of the intake air can be improved. In addition, the upper surface of the fuel tank 15 is brought close to and along the bottom wall of the planar air cleaner 14, and
Since the upper front end of the fuel tank 15 is close to the carburetor bottom 12a, the fuel tank 15 can be compactly disposed in a space formed below the carburetor 12 and the air cleaner 14. In addition, the upper surface of the fuel tank 15 can be formed so as to bulge rearward and upward along the bottom wall of the inclined air cleaner 14, so that the tank capacity can be increased.

In the above-described embodiment, an example in which the steering is performed by the hydraulic cylinder 7 has been described. However, an electric actuator or the like can be used instead of the hydraulic cylinder.
A structure that can be directly steered by the steering device 4 with a flexible link mechanism interposed between the knuckle 5a and the knuckle 5a may be employed.

〔The invention's effect〕

As described above, in the motorcycle according to the present invention, the left and right main frames are extended from the rear arm support to the front and upper sides of the sub-cylinder through the lower part of the seat front, and the steering device is provided at the front end. A frame is connected to the front part of the main frame, and a knuckle for rotatably supporting a front wheel is provided at a front part of the vehicle body, and a rear end part is supported to be able to swing up and down on the vehicle body side, and a front end part is capable of steering the knuckle. A front wheel suspension device having a lower arm and an upper arm for supporting the vehicle, connecting the steering device and the knuckle by a connecting member, supporting a fuel tank on a main frame, and lowering the lower portion of the fuel tank between the left and right main frames. And the lower surface is close to the upper surface of the transmission case of the engine. The sub-frame connected to the front of the main frame and the steering device provided on the sub-frame and the steering device provided on the sub-frame where the arm and the front wheel suspension device are arranged at a low position can be reduced in weight because no force is applied from the front wheels. . The fuel tank is supported by a lower main frame, and the lower part of the fuel tank is located between the left and right main frames and close to the upper surface of the transmission case. Air cleaner is arranged.

Therefore, the heavy members can be prevented from being located at a high position, and the heavy members can be arranged so as to be concentrated around the engine. It can be aimed at.

In addition, the left and right main frames have a certain width in the vehicle width direction because they require strength to support the engine and torsional rigidity. This width is wider than the portion corresponding to the front part of the seat of the seat rail which has conventionally supported the fuel tank.

Therefore, even if the lower portion of the fuel tank is arranged between the left and right main frames, the tank capacity does not decrease. Moreover, since the main frame is located at a lower position and the fuel tank is located between the cylinder and the seat,
As compared with the case where the fuel tank is arranged above the cylinder, the bracket for supporting the fuel tank does not need to protrude upward from the main frame, so that the fuel tank can be firmly supported.

Furthermore, the intake pipe extends obliquely upward and rearward from the intake port provided on the rear side of the cylinder, and an air cleaner communicating with this intake pipe via a carburetor is formed at an angle gentler than the gradient of the intake pipe from the intake port of the carburetor. Since the bottom wall of the air cleaner extends obliquely upward and rearward, and the bottom wall of the air cleaner is formed in a planar shape, and the upper wall of the air cleaner has a suction portion that opens rearward, both the intake pipe and the air cleaner tilt upward and rearward, and the air cleaner It is possible to reduce the bending of the intake passage from inside to the intake port of the engine, thereby reducing intake resistance and improving intake charging efficiency. In addition, the upper surface of the fuel tank is located close to the bottom wall of the planar air cleaner, and the upper front end of the fuel tank is located close to the bottom of the carburetor. In addition, the fuel tank can be arranged, and the upper surface of the fuel tank can be formed so as to bulge upward and rearward along the bottom wall of the inclined air cleaner, thereby ensuring sufficient tank capacity. it can.

[Brief description of the drawings]

FIG. 1 is a side view showing a motorcycle according to the present invention, and FIG. 2 is a plan view showing a schematic configuration of a front wheel suspension device. 1 ... frame, 1a ... main frame, 1b ... subframe, 1d ... rear arm support, 2 ... engine, 2a
…… Crankcase, 2b …… Cylinder, 3 …… Seat,
3a: Front of seat, 4: Steering device, 5: Front wheel suspension device, 5a: Knuckle, 5b: Lower arm, 5c ...
... Upper arm, 6 ... Front wheel, 12 ... Vaporizer, 12a ...
... bottom part, 13 ... intake pipe, 14 ... air cleaner, 15 ... fuel tank, M ... transmission case.

Continuation of the front page (56) References JP-A-62-134387 (JP, A) JP-A-62-1103282 (JP, A) JP-A-62-1103277 (JP, A) JP-A-61-292974 (JP) JP-A-1-28082 (JP, A) JP-A-1-109187 (JP, A) JP-A-62-10084 (JP, U) JP-B-52-30047 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) B62J 35/00 B62J 39/00 B62K 25/24

Claims (1)

(57) [Claims] An engine in which a cylinder leans forward is supported by left and right main frames, and a rear arm supporting a rear wheel is swingably supported at a lower rear portion of the main frame, and is provided at a rear side of the cylinder. A carburetor is attached to an intake pipe extending obliquely upward and rearward from the intake port so that the intake port is directed upward, and an air cleaner is connected to the intake port so as to be disposed above a cylinder, and the cylinder is connected to the cylinder. And a motorcycle in which a fuel tank is disposed between a carburetor and a seat at an upper part of a vehicle body, wherein the left and right main frames are extended from a rear arm support portion to a position above a front side of the seat and to a cylinder side forward and upward. A steering device that connects a subframe provided at a front end portion to a front portion of the main frame, and a knuckle that rotatably supports front wheels at a front portion of the vehicle body; A front wheel suspension device having a lower arm and an upper arm whose front end is slidably supported on the vehicle body side and whose front end portion slidably supports the knuckle, and the steering device and the knuckle are connected by a connecting member; The air cleaner extends obliquely upward and rearward from the inlet of the carburetor at an angle lower than the slope of the intake pipe,
While forming the bottom wall of this air cleaner in a flat shape,
Forming a suction portion opening rearward on the upper wall of the air cleaner, supporting the fuel tank on the main frame,
The lower part of this fuel tank is made to face between the left and right main frames, the lower surface is made close to the upper surface of the engine transmission case, and the upper surface of the fuel tank is made close to the bottom wall of the air cleaner. A motorcycle characterized in that an upper front end of the vehicle is close to a bottom of the carburetor.