JP2505683B2 - 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, when the running wind is not expected and the running wind is low during low speed running such as a muddy road, the temperature of the engine may rise and overheating may occur.

In view of the above points, the present invention has an object to obtain a liquid cooling structure for a motorcycle engine in which the amount of lubricating liquid contained is increased to reliably prevent overheating.

[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 arranged along a lower portion of the engine crankcase. A liquid storage tank whose front portion is inclined upward and upward and which is formed in a long casing in the front-rear direction is provided, and the engine and the heat exchanger, the heat exchanger and the liquid storage tank, and the liquid storage tank and the engine are provided. A circulation circuit is formed by connecting the respective parts with connecting pipes, and the front part of the liquid storage tank that is long in the front-rear direction is positioned near the joint surface between the crankcase and the cylinder.

[0005]

During operation of the engine, the circulating liquid for cooling stored in the liquid storage tank is sent to the engine, where the circulating liquid heated by cooling the engine is supplied to the heat exchanger and cooled. It is returned to the liquid storage tank again to effectively cool the engine. In addition, the circulating fluid for cooling is increased by the capacity of the liquid storage tank, and the traveling wind efficiently hits the liquid storage tank to improve the cooling performance.

[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 part of the down tube 5 is branched into two down tubes 7 and 7 that are spaced apart in the vehicle width direction (Fig. 2). These main frames 12, down tubes 5 and down tubes 7 and 7 The engine 6 is mounted inside the constituted frame space.

By the way, a heat exchanger 9 for cooling the circulating fluid is arranged in the upper front part of the engine, and the two down tubes 7, 7 are arranged under the crankcase below the engine. A liquid storage tank 1 for storing the circulating liquid is disposed along the down tube 7. The front portion of the liquid storage tank is located near the joint surface between the engine crankcase and the cylinder.

As shown in FIGS. 2 to 4, the liquid storage tank 1 is formed in a casing shape which is long in the front-rear direction, in which the front portion is inclined upward and the rear portion is extended, and the lower surface is a ship bottom shape 2. At the same time, the upper surface is shaped according to the front and lower shapes of the engine crankcase 13, and the down tube 7 is tightened with bolts and nuts so that the front upper end thereof is located below the engine exhaust port 14. It is worn.

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 inlet 3 is connected to the heat exchanger 9 via a connecting pipe 8a. Has been done. The heat exchanger 9 is connected to the upper portion of the engine 6 via a connecting pipe 8b, and the engine 6 is further 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 circulating fluid for cooling can be increased by the capacity of the storage tank 1 attached to the lower portion of the engine 6 without increasing the capacity of the heat exchanger 9.
Since the increased circulating fluid circulates while cooling the inside of the engine 6, the heat exchanger 9, and the storage tank 1, the temperature rise of the engine 6 can be prevented even when the motorcycle is stopped or running at a low speed in a muddy road. Moreover, the storage tank 1 does not take up much space for installation, and does not disturb the driving operation of the driver.

[0012]

As described above, according to the present invention, the liquid storage tank is arranged below the heat exchanger arranged in front of the engine so that the front portion thereof is located near the joint surface between the crankcase and the cylinder of the engine. Since the circulation liquid is increased, the traveling wind efficiently hits the liquid storage tank to cool the circulation liquid, and the temperature rise of the engine and the like can be reduced to prevent overheating. 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, the front of the cylinder part, which becomes hot, is not blocked by the liquid storage tank, and traveling air (cooling air) can be sufficiently applied to the cylinder, so that sufficient cooling performance can be ensured.

[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 15 Front Fender

Claims (1)

(57) [Claims] 1. A heat exchanger is disposed above and below a main frame that extends below a main frame extending rearward from a rear portion of a head pipe, and a crankcase of the engine is provided.
Along the bottom, it is arranged a liquid storage tank which is formed in a long casing shaped in the longitudinal direction which is inclined forward and upward front, between the engine and the heat exchanger, and between the heat exchanger and the liquid storage tank and
Connect the liquid storage tank and the engine with connecting pipes.
To form a circulation circuit, and to
The front portion of the body storage tank is connected to the crankcase and the cylinder.
A liquid cooling structure for motorcycle engines, characterized by being located near the joint surface of .