JP2899033B2 - Component arrangement structure in front of motorcycle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a structure for arranging components at a front portion of a motorcycle.

(Prior Art) Conventionally, there is a motorcycle configured as follows.

That is, an engine is supported on the body frame, and an exhaust pipe for the engine temporarily extends forward from the cylinder of the engine, and then extends forward.
A rear pipe disposed on one side of the engine and having one end connected to the extension end of the front pipe and the other end extending rearward;

A radiator is provided in front of the cylinder of the engine and is supported by the body frame. A cooling water pump is attached to the engine, and a cooling water feed pipe connecting the cooling water pump to a lower end of the radiator is provided.

In the above case, it is conventionally known that if the length of the exhaust pipe is lengthened to a certain extent, the inertia effect of the exhaust is improved and the engine performance is improved.

(Problems to be Solved by the Invention) However, in the above configuration, simply increasing the length of the exhaust pipe increases the area of the exhaust pipe in front of the radiator in front of the radiator as viewed from the front of the vehicle body. Smooth flow of the traveling wind is impeded, and the cooling effect of the radiator may be reduced.

Further, since the rear pipe, the cooling water pump and the feed pipe are located at approximately the same position in the front-rear direction of the vehicle body, the cooling water pump and the feed pipe are easily heated by heat from the rear pipe. The cooling effect of the radiator associated with the water pump and the feed pipe may be reduced.

Moreover, since the rear pipe usually forms an expansion chamber and has a large outer dimension, the rear pipe may hinder the piping work of the feed pipe.

(Object of the Invention) The present invention has been made in view of the above-mentioned circumstances, and enables the exhaust pipe to be sufficiently long. Even in such a case, the cooling effect of the radiator is kept good. It is another object of the present invention to facilitate the work of piping a feed pipe for connecting a cooling water pump to a radiator.

(Structure of the Invention) In order to achieve the above object, the present invention is characterized in that an engine 25 is supported on a vehicle body frame 2, and an exhaust pipe 55 for the engine 25 is once directed forward from a cylinder 28 of the engine 25. And a front pipe 56 that extends rearward, and is disposed on one side of the engine 25, one end of which is connected to the extending end of the front pipe 56 and the other end of which is rearward. A radiator 61 is disposed in front of the cylinder 28 of the engine 25 and is supported by the vehicle body frame 2, a cooling water pump 71 is attached to the engine 25, and the cooling water pump 71 is In the structure for disposing components at the front part of the motorcycle provided with a feed pipe 72 for cooling water connected to the lower end of the radiator 61, 1) the front pipe 56 extends forward and downward from the cylinder 28. Later, it extends to one side in the vehicle width direction, A first bent pipe 56a extending upward, and extending from the upper end of the first bent pipe 56a to the other side opposite to the one side through the front side from the lower end of the radiator 61. A second bent tube 56 extending downward and then extending toward the rear tube 60
2) The lower end of the radiator 61 and the upper end of the second bent tube 56b of the front tube 56 are overlapped with each other in a vehicle front view. 3) The cylinder 28 is mounted in the vehicle width direction. The point is that the cooling water pump 71 and the feed pipe 72 are disposed on the vehicle body side opposite to the rear pipe 60 as a reference.

(Operation) The operation of the above configuration is as follows.

An exhaust pipe 55 once extends forward from the cylinder 28 of the engine 25, and then extends forward.A front pipe 56 extends rearward. Tube 56
A rear tube 60 connected to the extension end of the cylinder and extending the other end rearward, and a radiator 61 is disposed in front of the cylinder 28,
In the case where a cooling water feed pipe 72 for connecting a cooling water pump 71 attached to the engine 25 to the radiator 61 is provided: 1) After the front pipe 56 extends forward and downward from the cylinder 28 A first bent tube 56a extending to one side in the vehicle width direction and then extending upward; and a first bent tube 56a extending from an upper end of the first bent tube 56a to a front side of a lower end of the radiator 61. A second bent tube 56 extending toward the other side opposite to the side and extending downward, and then extending toward the rear tube 60
b.

For this reason, the front pipe 56 has a cylinder
A substantially "" -shaped shape is drawn with the position of the stroke 28 as the starting point of the stroke order. In other words, the front tube 56 is piped in a well-balanced manner with the cylinder 28 substantially at the center.

Therefore, the front pipe 56 can use the space on each of the left and right sides of the vehicle body without bias, and the length of the exhaust pipe 55 can be made longer accordingly.

2) When viewed from the front of the vehicle body, the lower end of the radiator 61 and the upper end of the second bent tube 56b of the front tube 56 are overlapped.

Therefore, even if the exhaust pipe 55 is sufficiently long as described above, it is possible to prevent the exhaust pipe 55 from obstructing the flow of the traveling wind toward the radiator 61.

3) In the vehicle width direction, the cooling water pump is provided on the side of the vehicle body opposite to the rear pipe 60 with respect to the cylinder 28.
71 and a feed pipe 72 are provided.

Therefore, the cooling water pump 71 and the feed pipe 72
Is largely separated from the rear tube 60 in the vehicle width direction, and the heating by the rear tube 60 is suppressed.

Further, as described above, since the feed pipe 72 is separated from the rear pipe 60 in the vehicle width direction, even if the outer dimensions of the rear pipe 60 are large, the feed pipe 72 is not disturbed by the rear pipe 60 and is provided around the feed pipe 72. A large work space is secured.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

1 to 6, reference numeral 1 denotes a motorcycle and reference numeral 2 denotes a body frame thereof.

The vehicle body frame 2 has a head pipe 3 at the front thereof, and left and right main frames 4, 4 made of sheet metal and having a box-shaped section with a vertically long cross section from the head pipe 3 toward the rear lower side. The left and right main frames 4, 4 are firmly connected to each other by a main cross pipe 5.

Rear arm brackets 7 extend downward from the rear ends of the main frames 4, respectively, and the left and right rear arm brackets 7,
2 is pivoted up and down freely.

Down tubes 13 extend downward from the front ends of the main frames 4 below the main frames 4 and 4, respectively.

A front fork 15 is pivotally supported on the head pipe 3 so as to be steerable. And this front fork 15
The front wheel 16 is supported at the lower end of the front fork 15
The handle 17 is attached to the upper end of. In the above case, the front fork 15 includes a steering shaft (not shown) pivotally supported in the head pipe 3 so as to be rotatable around an axis, an upper bracket 15a attached to upper and lower ends of the steering shaft, and a lower shaft. The front wheel 16 is supported between the lower ends of the left and right fork tubes 15c, as described above, and includes a bracket 15b and a pair of left and right fork tubes 15c which are supported by the two brackets 15a and 15b and are extendable and retractable. The front wheel 16 is provided with a front fender 16a.

On the other hand, a rear wheel 18 is supported on the swinging end of the rear arm 12. 19 is a shock absorber, and this shock absorber 19 is
From the vehicle body 2 via the rear arm 12.

An engine 25 is provided below the left and right main frames 4,4. The engine 25 is a two-stroke single-cylinder engine. A power transmission device 27 is connected to the rear of the crankcase 26, and a cylinder 28 projects from the upper surface of the crankcase 26 to the upper front. A cylinder head 29 is mounted on the cylinder 28.

The upper end of the cylinder head 29 is screwed to the main cross pipe 5 with a bolt 30 to be supported by the left and right main frames 4, 4.
Is screwed to the lower end of each down tube 13 with a bolt 31. Further, the rear end of the power transmission device 27 is supported by the pivot shaft 11, whereby the engine 25 is firmly supported by the body frame 2. Have been.

Further, a drive wheel 33 is provided on the power transmission device 27 side, while a driven wheel 34 is attached to the rear wheel 18,
A transmission chain 35 is wound around the two chain wheels 33, 34.

A carburetor 40 and an air cleaner 41 are connected to an intake port formed on the rear surface of the cylinder 28. Also,
A fuel tank 46 for supplying fuel to the carburetor 40 is provided. The fuel tank 46 is made of resin and is located near the upper part of the engine 25 and between the left and right main frames 4, 4, so that the mass of the vehicle body is concentrated and the center of gravity is reduced. As shown in FIGS. 3 and 5, the front portion of the fuel tank 46 is supported by the left and right main frames 4, 4 via a pair of left and right cushioning members 47, 47, and the rear end thereof is It is supported on the main cross pipe 5 by another cushioning material 47 '. A cap 48 for opening and closing the fuel inlet is provided on the front upper surface of the fuel tank 46.

A cover 49 is provided to entirely cover the upper surfaces of the air cleaner 41 and the fuel tank 46, and rubber is attached to the upper surface of the cover 49 to form a seat 50. In FIG. 6, reference numeral 53 denotes a kick pedal of a kick starter.

In the exhaust port formed on the front surface of the cylinder 28,
An exhaust pipe 55 made of sheet metal is connected. This exhaust pipe 55
A front pipe 55 that once extends forward from the exhaust port and then extends rearward, and one end is disposed on one side of the engine 25 and has one end that is an extension end of the front pipe 56. And a rear tube 60 whose other end extends rearward.

The front pipe 56 extends forward and downward from the exhaust port of the cylinder 28, and then extends rightward as one side in the vehicle width direction.
Next, a first bent pipe 56a extending upward,
It extends from the upper end of the bent tube 56a to the left, which is the other side opposite to the one side, and extends downward, and then is folded upward to extend toward the rear tube 60. And a second bent tube 56b. The upper end of the second bent tube 56b extends rearward, bypassing the side of the down tube 13, and the front end of the rear tube 60 is connected thereto.

That is, the front pipe 56 is provided so that the length of the pipe is sufficiently long by effectively utilizing the excess space extending vertically and horizontally along the front side of the engine 25 as a whole.

On the other hand, the rear pipe 60 has a muffler 57 connected to the front pipe 56, and this muffler 57 is, as shown particularly in FIG. It is disposed in a space created between the main frame 4 and the left side of the crankcase 26. In this case, as shown in FIG. 6, the muffler 57 is provided closer to the inside of the vehicle body than the imaginary surface 62 connecting the outer surface of the main frame 4 and the outer surface of the crankcase 26. The movement of the rider's foot
It is not inhibited by muffler 57.

Also, a connecting pipe 58 extends rearward from the rear end of the muffler 57.
The connecting pipe 58 is connected to the left rear arm bracket 7.
And the buffer 19 pass through the space created. A silencer 59 is connected to the rear end of the connection pipe 58.

Thus, when the engine 25 operates, outside air is sucked through the air cleaner 41, which
Is mixed in a carburetor 40, and the air-fuel mixture is sucked into the cylinder 28, where it is burned. Then, the combustion gas is exhausted through an exhaust pipe 55. At this time, the power generated in the engine 25 is transmitted to the rear wheel 18 via the power transmission device 27 and the transmission chain 35, so that the motorcycle 1 can travel. Becomes

In FIG. 3, a cable body 63 such as a clutch wire or a wire harness is provided extending downward from the handle 17 toward the lower side of the main frame 4. The cord 63 extends below the main frame 4 through a space surrounded by the head pipe 3, the upper bracket 15a, the lower bracket 15b, and the left fork tube 15c. It is supported by a protruding bracket 64. In this case, the cable body 63 may pass through a space surrounded by the right fork tube 15c instead of the left fork tube 15c.

According to the above configuration, since the cable body 63 is near the head pipe 3, when the steering wheel 17 is steered,
Rotational movement of the rope 63 that is to be rotated with the movement of the cable 17 is suppressed to a small value. Therefore, the cable bodies 63 are prevented from interfering with each other, and the bending of the cable bodies 63 is suppressed to be small, thereby preventing the cable bodies 63 from being damaged. Further, the cord 63 is surrounded by the head pipe 3, the lower bracket 15b, and the fork tube 15c, and is prevented from wobbling left and right.

Further, when the front wheel 16 receives an impact and the fork tubes 15c are reduced during traveling of the motorcycle 1, the space between the lower bracket 15b and the front fender 16a becomes narrower. It is also prevented from being pinched.

1, 3 and 5, a device for cooling the cylinder 28 by water cooling is provided. This device has a radiator 61, and this radiator 61
The body frame 2 which is disposed in front of the 25 cylinders 28
It is supported by. The upper part of the radiator 61 is disposed between the left and right main frames 4, 4, and the lower part of the radiator 61 is disposed between the lower ends of the down tubes 13, 13 and fastened to these down tubes 13 by fasteners 66. Have been. Further, a motor driven cooling fan 65 is provided corresponding to the rear surface of the radiator 61.

In the above case, the second bent tube 56b of the front tube 56 extends in the vehicle width direction through the front side of the lower end of the radiator 61 and extends in the vehicle width direction (FIG. 1). The lower end and the upper end of the second bent tube 56b are overlapped.

A lower end of an injection pipe 68 for injecting cooling water is connected to an upper part of the radiator 61, and an upper end side of the injection pipe 68 extends upward between front ends of the left and right main frames 4, 4, and a cap 69 is provided at an upper end thereof. Installed. Further, the lower end of the radiator 61 is connected to a cooling water pump 71 attached to the right end of the crankcase 26 by a feed pipe 72, and the cooling water in the radiator 61 cooled by the cooling fan 65 or the traveling wind is provided. The cooling water is pumped into the cylinder 28 by the cooling water pump 71 to cool the cylinder 28.

Further, the upper end of the cylinder head 29 is connected to the upper part of the radiator 61 by a return pipe 73, and the cooling water after cooling the cylinder 28 is returned to the radiator 61 through the return pipe 73. .

7, a relay switch 74, a control unit 75, and a vehicle speed sensor 76 are connected to an electric motor of the cooling fan 65, and the cooling fan 65 is controlled as follows.

That is, when the vehicle speed is low, such as 20 km / h, the cooling fan 65 is rotated forward and the cooling air from the cooling fan 65 overcomes the traveling wind and is blown forward as shown by the arrow A in the drawing. It has become. According to this, it is possible to prevent the hot air that has passed through the radiator 61 from heating the fuel tank 46.

On the other hand, when the vehicle speed exceeds 20 km / h, at high speeds, the cooling fan 65 is rotated in reverse, so that the cooling air from the cooling fan 65 is blown backward as shown by the arrow B in the drawing. Has become. In this case, since the traveling wind also increases, the temperature of the air that has passed through the radiator 61 is relatively low, so that the air that has passed through the radiator 61 is prevented from heating the fuel tank 46. The occurrence of vapor lock overheat and the like is prevented, and the engine performance is kept good.

7 to 9, the cooling fan 65 is provided on the rear side of the radiator 61 and has a circular casing in a front view.
The casing 65a is screwed to the radiator 61 by a bracket 65b extending radially.
In addition, the motor 65c is formed into a casing by the bracket 65b.
Installed in the center of 65a. And this electric motor 6
A fan blade 65d is attached to the output shaft of 5c, and the fan blade 65d is located in the casing 65a.

A protective net 65e that covers the cooling fan 65 from the rear side
Is detachably attached to the rear edge of the casing 65a by a tightening string 65f. The protection net 65e is mainly used for maintenance and inspection of the vehicle body, and prevents a tool from touching the fan blade 65d.

In addition, 78 in FIG. 3 is a footrest, 79 is a sheet metal engine guard, the front end of which is screwed to the lower ends of the left and right down tubes 13, 13 with bolts 80, and the rear end of which is the rear arm with bolts 81. It is screwed to the bracket 7. The engine guard 79 protects the engine 25 and the power transmission device 27 reliably. The angle θ between the front end of the engine guard 79 and the lower surface of the front pipe 56 with respect to the horizontal direction is
The angle is set to 30 ° or more, that is, the front tube 56 is centralized and compact. Thus, the mass is concentrated.

(Effect of the Invention) According to the present invention, an engine is supported by a body frame, and an exhaust pipe for the engine once extends forward from a cylinder of the engine, and then extends forward. A rear pipe disposed on one side of the engine, one end of which is connected to an extension end of the front pipe and the other end of which extends rearward, and a radiator is disposed in front of a cylinder of the engine. A cooling water pump attached to the engine, and a cooling water feed pipe connecting the cooling water pump to a lower end of the radiator. In the structure, 1) the front pipe extends from the cylinder toward the front and downward, then extends to one side in the vehicle width direction, and then extends upward; Above from the top of the bent tube A second bent pipe extending forward from the lower end of the radiator toward the other side opposite to the one side and extending downward, and then extending toward the rear pipe; ing.

For this reason, the front tube draws a substantially "-" shape with the position of the cylinder as the starting point of the stroke order when viewed from the front of the vehicle body. Piped.

Therefore, the front pipe can utilize the space on each of the left and right sides of the vehicle body without bias, and the length of the exhaust pipe can be made longer accordingly.

2) When viewed from the front of the vehicle body, the lower end of the radiator and the upper end of the second bent pipe of the front pipe are overlapped.

Therefore, even if the exhaust pipe is sufficiently long as described above, it is possible to prevent the exhaust pipe from obstructing the flow of the traveling wind toward the radiator.

Therefore, the cooling effect of the radiator is kept good.

3) In the vehicle width direction, the cooling water pump and the feed pipe are disposed on the side of the vehicle body opposite to the rear pipe with respect to the cylinder.

For this reason, the cooling water pump and the feed pipe are largely separated from the rear pipe in the vehicle width direction, so that heating by the rear pipe is suppressed.

Therefore, the cooling effect of the radiator associated with the cooling water pump and the feed pipe is kept good.

In addition, as described above, since the feed pipe is separated from the rear pipe in the vehicle width direction, even if the external dimensions of the rear pipe are large, a wide working space is secured around the feed pipe without being obstructed by the rear pipe. Is done.

Therefore, the piping work of the feed pipe can be easily performed.

[Brief description of the drawings]

1 is a front view, FIG. 2 is an overall side view of a motorcycle, FIG. 3 is a partially enlarged view of FIG. 2, FIG. 4 is a plan view, and FIG. FIG. 6 is a sectional view taken along line VV of FIG. 3, FIG. 6 is a sectional view taken along line VI-VI of FIG.
FIG. 8 is a partially enlarged view of FIG. 3, and FIG.
FIG. 9 is a partial enlarged view of FIG. DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 25 ... Engine, 28 ... Cylinder, 55 ... Exhaust pipe, 56 ... Front pipe, 56a ... First bent pipe, 56b ... Second bent pipe, 60 ... Rear pipe, 61 ... Radiator, 71 ... cooling water pump,
72… Sending pipe.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-301192 (JP, A) JP-A-59-104824 (JP, U) JP-A-60-128927 (JP, U) (58) Investigation Field (Int.Cl. ⁶ , DB name) B62M 7/02 B62J 39/00

Claims (1)

(57) [Claims] An exhaust pipe for an engine is supported on a body frame, and an exhaust pipe for the engine once extends forward from a cylinder of the engine and then extends forward. A rear pipe disposed laterally and having one end connected to an extension end of the front pipe and the other end extending rearward, and a radiator disposed in front of a cylinder of the engine, and A cooling water pump attached to the engine, and a cooling water feed pipe connecting the cooling water pump to the lower end of the radiator. The front pipe extends forward and downward from the cylinder, then extends to one side in the vehicle width direction, and then extends upward, and from the upper end of the first bent pipe. From the lower end of the radiator And a second bent tube extending toward the other side opposite to the one side and extending downward through the front side, and then extending toward the rear tube. 3) The lower end of the radiator and the upper end of the second bent pipe of the front pipe are overlapped, and 3) the vehicle body side opposite to the rear pipe with respect to the cylinder in the vehicle width direction. The structure of disposing components at the front of a motorcycle in which the cooling water pump and the feed pipe are disposed.