JP2505684B2 - Liquid cooling structure for motorcycle engine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid cooling structure for a motorcycle engine.

[0002]

2. Description of the Related Art In a motorcycle of a race type, in order to improve engine cooling performance, engine cooling water, oil lubricant, etc. are used in a heat exchanger. However, in the case of motorcycles, there are large restrictions on the size of the heat exchanger, the installation location, etc., so it is not possible to select a heat exchanger of a free size like an automobile, and it is cooled by a fan. Since there is no place to install a fan to blow the wind, the running wind is applied to the heat exchanger to cool it. For this reason, the engine temperature may rise and the engine may overheat when the vehicle is in a state where the traveling wind cannot be expected or when the traveling wind is low during traveling at low speed such as a muddy road.

In view of the above point, the present invention has an object of providing a liquid cooling structure for an engine for a motorcycle, in which the amount of circulating fluid stored is increased and overheat can be reliably prevented.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a heat exchanger is arranged above and below a main frame extending rearward from a rear portion of a head pipe, and a heat exchanger is provided along a lower portion of the engine crankcase. A liquid storage tank having a front portion that is inclined forward and upward and formed in a long casing in the front-rear direction, and is provided between the engine and the heat exchanger, between the heat exchanger and the liquid storage tank, and between the liquid storage tank and the engine. The exhaust pipes connected to the exhaust ports provided in front of the engine are bent and extended from the front of the engine to one side in the width direction of the vehicle, and the circulation pipes are connected by connecting pipes. It is characterized in that the heat exchanger and the upper end of the liquid storage tank are connected by a connecting pipe at a position on the other side in the vehicle width direction opposite to the bent exhaust pipe.

[0005]

After the circulating fluid for cooling stored in the liquid storage tank is supplied to the engine during operation of the engine, the circulating fluid heated by the cooling of the engine is sent to the heat exchanger and cooled. It is returned to the liquid storage tank again to effectively cool the engine. Moreover, the amount of the circulating liquid for cooling can be increased by the capacity of the liquid storage tank, and the cooling performance is improved by the increased amount of circulating liquid. By arranging the connecting pipe between the heat exchanger and the liquid storage tank on the side of the other vehicle opposite to the bent exhaust pipe, the connecting pipe can be separated from the exhaust pipe that becomes hot.

[0006]

1 is a partial side view of a motorcycle according to the present invention, in which a main frame 1 of a head pipe 10 extends rearward from a rear portion thereof through a lower portion of a fuel tank 11.
2 is provided, and one down tube 5 extending obliquely downward from the rear portion of the head pipe 10 is provided. The lower portion of the down tube 5 is cooled in the vehicle width direction and then returned to the liquid storage tank to effectively cool the engine. Moreover, the amount of the circulating liquid for cooling can be increased by the capacity of the liquid storage tank, and the cooling performance is improved by the increased amount of circulating liquid. By arranging the connecting pipe between the heat exchanger and the liquid storage tank on the side of the other vehicle opposite to the bent exhaust pipe, the connecting pipe can be separated from the exhaust pipe that becomes hot.

[0006]

1 is a partial side view of a motorcycle according to the present invention, in which a main frame 1 of a head pipe 10 extends rearward from a rear portion thereof through a lower portion of a fuel tank 11.
2 is provided, and one down tube 5 extending obliquely downward from the rear portion of the head pipe 10 is provided. The lower portion of the down tube 5 is branched into two down tubes 7, 7 spaced apart in the vehicle width direction. A frame composed of the main frame 12, the down tube 5, the down tubes 7, 7, etc. The engine 6 is mounted inside the space. The exhaust pipe 6 connected to the exhaust port 14 of the engine 6
a is projected forward, and is bent in a U shape on the right side of the vehicle body with respect to the traveling direction of the vehicle.

By the way, a heat exchanger 9 for cooling the circulating fluid is provided in the upper front portion of the engine, and the circulating fluid is placed between the two down tubes 7 at the lower portion of the engine crankcase. A liquid storage tank 1 for storing the liquid is disposed along the down tube 7.

The liquid storage tank 1 is formed in a long casing shape in which the front portion is tilted upward and the rear portion is extended, the lower surface is a ship bottom shape 2, and the upper surface is in front of and below the engine crankcase 13. It is shaped according to the side shape, and is fastened to the down tube 7 by using bolts and nuts so that the upper end of the front part is located below the exhaust port 14 of the engine.

The liquid storage tank 1 is provided with an inlet 3 and an outlet 4 for circulating the circulating liquid on the left and right of the front upper end thereof, and the vehicle advancing with the inlet 3 opposite to the bent exhaust pipe 6a. It is connected to the heat exchanger 9 via a connecting pipe 8a arranged on the left side in the direction. The heat exchanger 9 is connected to the engine 6 via the connecting pipe 8b.
The engine 6 is connected to the outlet 4 of the storage tank 1.

During operation of the engine, however, the circulating liquid in the liquid storage tank sequentially circulates through the engine 6 and the heat exchanger 9.

Therefore, in this motorcycle, the volume of the circulating fluid for cooling can be increased by the volume of the storage tank 1 attached to the lower portion of the engine 6 without increasing the volume of the heat exchanger 9. Since the engine 6, the heat exchanger 9 and the liquid storage tank 1 are circulated while being cooled, the temperature rise of the engine 6 can be prevented even when the motorcycle is stopped or running at a low speed on a mud road. Moreover, the installation of the liquid storage tank 1 does not take up much space and does not interfere with the driving operation of the driver.

[0012]

As described above, according to the present invention, the liquid storage tank is connected below the heat exchanger arranged in front of the engine through the heat exchanger and the connecting pipe, and the heat exchanger and the liquid are connected. Since a circuit for circulating the circulating liquid is provided between the storage tank and the engine, the circulating liquid is increased in quantity, and the liquid is cooled by both the heat exchanger and the liquid storage tank.
Overheating can be prevented by reducing the temperature rise of the engine etc. Moreover, the circulating fluid can be radiated favorably not only while the motorcycle is traveling but also at low speed traveling on the mud road, because the circulating fluid receives traveling wind and mud. Further, since the connecting pipe is arranged on the other side of the bent exhaust pipe, the connecting pipe is separated from the exhaust pipe that becomes hot, and the heat from the exhaust pipe is prevented from being transferred to the circulating fluid passing through the connecting pipe. Therefore, the cooling performance is improved.

[Brief description of drawings]

FIG. 1 is a side view of the present invention,

FIG. 2 is a perspective view of the same.

FIG. 3 is a plan view of a liquid storage tank,

FIG. 4 is a side view of the same.

[Explanation of symbols]

 1 Liquid Storage Tank 2 Ship Bottom Type 5, 7 Down Tube 6 Engine 9 Heat Exchanger 10 Head Pipe 11 Fuel Tank 12 Main Frame

Claims (1)

(57) [Claims] Claim: What is claimed is: 1. A heat exchange is performed in front of and above an engine mounted below a main frame extending rearward from a rear portion of a head pipe.
Of the crankcase of the engine
A long casing in the front-rear direction in which the front part is inclined forward and upward along the lower part.
A liquid storage tank formed in the shape of
Between heat exchangers, between heat exchangers and liquid storage tanks, and
Connect the liquid storage tank and the engine with connecting pipes.
To form a circulation circuit, and further in front of the engine
It is bent extends the exhaust pipe connected to the exhaust port from the front of the engine in the width direction of one side of a vehicle provided Rutotomo
On the other side of the vehicle in the width direction on the side opposite to the bent exhaust pipe.
Position, the heat exchanger and the upper end of the liquid storage tank
A liquid cooling structure for motorcycle engines, characterized in that they are connected by connecting pipes .