JP2725185B2 - Radiator for motorcycles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a radiator device of a motorcycle for cooling cooling water of a water-cooled engine.

(Prior art) In the case of a motorcycle equipped with a water-cooled engine, a radiator for cooling and circulating the cooling water is attached to a down tube in front of the engine unit to allow passage of a heat exchange wind. Many are designed to ensure a sufficient amount.

However, in the radiator attached to the down tube,
It is easy to lose the function due to the mud splashed by the front wheel.
In addition, since the front of the engine is closed, the air cooling effect of each part of the engine due to the traveling wind cannot be expected. In particular, the carburetor and the air cleaner disposed behind the engine are likely to become hot, which may cause a decrease in output. Furthermore, since the mounting position of the engine unit is shifted toward the rear due to the presence of the radiator, there is a problem that the load on the front wheels is insufficient and the steering stability may be affected.

In order to avoid such a problem, a radiator is conventionally installed at a place other than the front of the engine. For example, Japanese Patent Laid-Open No. 55-140670 discloses a radiator provided below a container such as a fuel tank disposed behind a head pipe. A radiator that is substantially horizontal is installed, and traveling wind is introduced into the radiator by a baffle tube formed on the bottom of the container or the like.

This prevents contamination by mud splashes and provides an air-cooling effect on the engine.However, for the radiator, since the traveling wind is deflected downward and introduced, the air volume is smaller than that attached to the down tube. The cooling effect is inferior. Further, air heated by heat exchange with the radiator may easily hit the carburetor, which may lead to a decrease in output.

(Problems to be Solved by the Invention) As described above, the conventional radiator device for a motorcycle is
When installed at the front of the down tube in order to increase the heat exchange rate, the air cooling action of the engine or the carburetor is hindered, and when installed at a place other than the front of the down tube, the heat exchange rate is reduced.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above circumstances, and has as its object to obtain a radiator device for a motorcycle, which has a sufficient air cooling effect on an engine and a carburetor and has a high radiator heat exchange rate. Things.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, a motorcycle radiator device according to the present invention has an engine unit mounted in a central portion of a vehicle body, a fuel tank disposed above the engine unit, and Automatic 2 covered with cowling from both sides of the engine unit
In the motorcycle, the bottom surface of the fuel tank is inclined obliquely downward toward the rear of the vehicle body so that a concave chamber is formed on the tank bottom surface between both sides of the fuel tank. , A radiator inclined downward and rearward is arranged, and the inlet cap of the radiator is projected from the upper surface of the front part of the fuel tank, and a wind guide port is opened in front of the cowling, and a duct following the wind guide port is provided. It is an opening at the front end of the concave chamber.

(Operation) With such a configuration, the running wind is directly applied to the engine unit mounted in the center portion of the vehicle body, and each part of the engine is air-cooled. Particularly, it prevents an adverse effect on the output caused by an increase in the temperature of the carburetor or the air cleaner.

On the other hand, since the radiator is installed across the passage formed below the fuel tank and the seat, the traveling wind can travel straight from the head pipe to the rear of the passage, and the resistance is low, so the air volume is large and the cooling efficiency of the radiator is high. .

Also, since the lower end of the radiator is located above the rear upper end of the rear end of the cylinder head, the air that passes through the radiator and is heated by heat exchange does not touch the cylinder head or the carburetor, and the air cooling effect is not diminished. .

(Embodiment) Hereinafter, a description will be given of a diagram showing an embodiment of the present invention.

The figure shows a motorcycle equipped with a cowling. The head pipe 1 is connected to a pair of left and right main pipes 2 extending rearward and curving downward, and a down tube 3 hanging downward and leading rearward, and a substantially trapezoidal vehicle body surrounded by the main pipe 2 and the down tube 3. The engine unit 4 is mounted in the space of the frame.

A front fork 5 is supported on the head pipe 1,
The front wheel 6 is pivotally supported at its lower end. A swing arm 7 is pivotally supported at the rear lower portion of the main pipe 2 so as to be able to swing up and down, and a rear wheel 8 is pivotally supported at the rear end.

A fuel tank 9 is placed on the upper surface of the main pipe 2, and a seat 11 and a pillion seat 11 a are placed on a seat rail 10 extending rearward from a rear upper end of the main pipe 2.

A carburetor 12 is connected rearward to an upper engine portion of the engine unit 4, and an air cleaner case 13 extending further below the rear seat 11 is connected.

The cowling 14 covers the front of the head pipe 1 from both sides of the engine unit 4. A wind guide port 15 is opened in the lower front part of the cowling 14 to guide the traveling wind A backward and blow it to the engine unit 4. Fins are formed on the outer surface of the cylinder block 16 of the engine, and are subjected to air cooling by the traveling wind A.

Next, the bottom surface 17 of the fuel tank 9 has a front end portion that is high and is gradually inclined downward toward the rear, so that a concave chamber 17a is formed between both sides.
Is formed. A radiator 19 inclined rearward and downward is disposed from the front end of the bottom plate 17 to the rear upper end of the cylinder head 18 of the engine. The upper half of the radiator 19 is housed in the concave chamber 17a.

The water inlet cap 20 of the radiator 19 protrudes from the front upper surface of the fuel tank 9, and the reservoir tank 21 is housed at the front end of the recessed chamber 17a. Reference numeral 22 denotes a cooling fan, and reference numerals 23a and 23b denote water hoses which form a circulation path between the radiator 19 and the engine water jacket.

A pair of left and right air guide ports 24 are formed on the front surface of the cowling 14, and a tail end 25a of a duct 25 connected to the rear thereof opens to the front end of the concave chamber 17a below the front end of the fuel tank 9. At the rear of the radiator 19, a passage 28 is formed which is surrounded by a rear portion of the fuel tank bottom surface 17 and the seat 11, a bottom surface of the air cleaner case 13, and an inner surface of the body cover 27.

The traveling wind B introduced from the wind guide port 24 flows into the duct 25,
17a, blows through the passage 28, while passing through the radiator 19 to cool the engine cooling water by heat exchange. Since the traveling wind B heated by the heat exchange proceeds straight to the passage 28 as described above, it does not contact the carburetor 12 and heat it.
Rather, since the traveling wind A is sucked from below the carburetor 12 by the flow velocity of the traveling wind B, the cooling of the carburetor 12 is promoted.
The air whose temperature is relatively lowered by this mixing is sucked through the air suction port 26 at the rear end of the air cleaner case 13, and there is no influence on the output due to the temperature of the suction air.

Since there is no radiator on the front portion of the down tube 3, the engine unit 4 can be moved forward, and the load on the front wheels can be increased to enhance the steering. Also, an oil cooler can be installed in place of the radiator to obtain the same effect.

〔The invention's effect〕

As described above, the radiator device for a motorcycle according to the present invention has an engine unit mounted in the center of the vehicle body, a fuel tank disposed above the engine unit, and a cowling covered from the front of the vehicle body to both sides of the engine unit with the cowling. In the motorcycle, the bottom surface of the fuel tank is inclined obliquely downward toward the rear of the vehicle body so that a concave chamber is formed on the tank bottom surface between both sides of the fuel tank. A radiator inclined downward and rearward is arranged over the upper end, and the inlet cap of the radiator is projected from the upper surface of the front part of the fuel tank, and a ventilation opening is opened in front of the cowling, and a duct following this ventilation opening is opened. Since the opening is formed at the front end of the concave chamber, the heat exchange rate of the radiator is high, and at the same time, the air heated by the heat exchange can contact the carburetor. To facilitate cooling of the engine each part by without, and traveling wind, it is possible to improve the engine output performance.

Further, since the inlet cap of the radiator is disposed on the upper surface of the front part of the fuel tank, it is possible to obtain effects such as easy injection of the cooling water into the radiator.

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle provided with a radiator device according to an embodiment of the present invention, FIG. 2 is a plan view, and FIG. 3 is a front view. 1 ... head pipe, 2 ... main pipe, 3 ... down tube, 4 ... engine unit, 9 ... fuel tank, 11 ... seat, 12 ... carburetor, 13 ... air cleaner case, 18 ... cylinder Head, 19 ... radiator.

Claims (1)

(57) [Claims] 1. An engine unit is mounted in the center of a vehicle body.
In a motorcycle in which a fuel tank is disposed above and covered with a cowling from the front of the vehicle body to both sides of the engine unit, the fuel tank has a bottom surface inclined obliquely downward toward the rear of the vehicle body, and the fuel tank is provided with both side surfaces. A concave chamber is formed on the bottom of the tank between the bottom of the fuel tank and a radiator inclined downward and rearward from the front end of the bottom of the fuel tank to the rear upper end of the engine cylinder head. A radiator device for a motorcycle, wherein the radiator device is provided so as to protrude and open a wind guide port in front of the cowling, and a duct following the wind guide port is opened at a front end of the concave chamber.