JPH0319363B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a suction cooling mechanism with a backflow prevention function.

(Prior Art) The main method of cooling in a heat engine is heat exchange with air, which includes air cooling, a natural cooling method using liquid cooling, and a forced cooling method. The former has a slow cooling effect and a low cooling limit, while the latter has an increased cooling capacity, but consumes engine output in the form of electricity, which ends up becoming a load on the engine, and in some cases. This is clearly visible.

Therefore, the inventor of the present invention utilizes the exhaust gas flow and the air flow obtained during driving to generate negative pressure, thereby increasing the amount of air passing through the engine, auxiliary equipment, and other peripheral devices that require cooling. He has completed an invention that improves the cooling effect with almost no load, and has already filed an application for some of the inventions.

However, the operating conditions of the engine are not uniform, and in the case of automobiles, when the accelerator is suddenly closed while negative pressure is being generated, or when the accelerator is similarly closed for engine braking, the cooling air flow using the above-mentioned invention is It was discovered that the exhaust system of the engine is affected by the engine exhaust system to which it is connected, causing instantaneous exhaust pulsation and backflow.

(Technical Problem) Although the above-mentioned backflow phenomenon is instantaneous, it obstructs the cooling airflow, lowers the cooling effect, and causes abnormal noise due to the vibration of the airflow, so it is necessary to eliminate this phenomenon. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a suction cooling mechanism with backflow prevention that solves the above-mentioned problems and provides a smooth cooling effect.

(Technical means) The above purpose is to create a cooling system by installing a negative pressure generating section with a narrowed cross-sectional area at a suitable location in the engine exhaust system pipe, leading to the engine body or its peripheral equipment, and taking in air flow. A pipe is connected to the negative pressure generating section, and a means for silencing the air flow in the pipe and a check valve for stopping a flow flowing backward through the pipe from the negative pressure generating section are connected to the pipe. This is achieved by establishing

In the above configuration, the negative pressure generating section is for generating energy to suck air to cool the engine, auxiliary equipment, and other peripheral devices, and in the embodiment, it is provided in the muffler that releases exhaust gas. There is.

The system for discharging the cooling airflow at a lower temperature than the exhaust gas is for discharging the airflow that has cooled the engine, auxiliary equipment, and other peripheral equipment, and is connected to the negative pressure generating section and uses its energy to suck in the desired cooling airflow. Ru. The objects to be cooled include an oil cooler, an intercooler, a radiator, or other equipment that generates heat, and the engine body.

The airflow toward the negative pressure generating section is muffled by the muffling means, but the check valve stops the cooling airflow sucked by the negative pressure if it backflows toward the engine, auxiliary equipment, etc. , provided to allow ventilation only in the discharge direction.

(Example) To explain the following using an example, FIGS. 1 and 2 schematically show a suction cooling mechanism in which the present invention is implemented, where 1 is a gasoline engine, and 2 is an oil cooler, that is, for cooling lubricating oil. 3 is a cooling part for cooling the oil cooler by suction airflow, 4 is an engine exhaust system pipe, 5 is a muffler, 6 is a negative pressure generating part provided at the rear end, 7 is a sub-silencer A check valve 8 is provided at the inlet (upstream side), and is installed between the cooling section 3 and the negative pressure generating section 6 via a conduit 9.

The muffler 5 has an exhaust flow path 10 in the center, and is connected to the exhaust pipe 4 via a first accelerating section 11 with a narrowed cross-sectional area. Negative pressure is generated in the negative pressure extraction section 6. The exhaust passage 10 has an inner cylinder 13, a middle cylinder 14, and an outer cylinder 15 that are arranged concentrically, and the inner cylinder 13 has an exhaust hole 1.
It has a noise-absorbing structure with a large number of cylinders 6 and a bypass path between it and the middle cylinder. 18 is a negative pressure extraction generating section 6
17 indicates a connection port.

The connection port between the sub-silencer 7 and the pipe line 9 is a check valve 8, and the illustrated valve includes a valve case 20 whose pipe diameter expands downstream, a ball valve 21, and a valve provided upstream of the valve case 20. Provided on the seat 22 and the downstream side, the ball valve 21 during normal operation
A porous body 24 having a large number of ventilation holes 23 that supports the
It is equipped with 25 is an inner pipe, 26 is an outer pipe, 27 is a muffling hole of the inner pipe 25, 28 is a tip cone, and the rear end of the outer pipe 26 is closed. The specific configuration of the sub-silencer 7 can also be changed,
It is sufficient if it has a de facto check valve and a sound deadening function.

Further, the object to be cooled can be selected from various devices other than the oil cooler or the engine itself, and the negative pressure generating section is not limited to the illustrated portion as long as it is the engine exhaust system.

(Operation of the Invention) In the present invention configured as described above, when the engine 1 starts, exhaust gas flows through the exhaust system pipe 4, creating negative pressure in the negative pressure outlet 6, and this negative pressure increases the engine rotational speed. becomes stronger as the value increases. When the engine 1 warms up, the temperature of the lubricating oil increases, and heat exchange with the surrounding air takes place.In particular, in the cooling section 3, airflow is sucked from the negative pressure generating section 6 through the pipe 9, so the cooling effect is further enhanced. This will be promoted.

During engine operation, exhaust noise is transmitted through the pipe 9 and released from the cooling section 3 to the outside, causing abnormal noise and noise, but in the present invention, the noise is muffled by the sub-silencer 7.

Furthermore, when the engine speed suddenly decreases due to accelerator operation, the suction negative pressure flow passing through the pipe 9 becomes unstable due to the influence of the exhaust gas flow into the muffler 5, and it will flow backward through the pipe 9. , this can also be prevented by operating the check valve 8. That is,
When reverse negative pressure is generated on the muffler 5 side, the ball valve 21 comes into contact with the valve seat 22 to prevent reverse flow from the pipe line 9.
When the rotational speed increases again and negative pressure starts to be generated normally, the cooling airflow passes through the porous body 24 and the cooling action is resumed.

(Effects of the Invention) Therefore, according to the present invention, exhaust noise and negative pressure vibrations caused by a sudden decrease in engine speed are emitted to the outside through the exhaust system of the cooling air flow, causing abnormal noise. Moreover, since no backflow of the cooling airflow occurs, remarkable effects such as the desired cooling effect can be achieved.

[Brief explanation of the drawing]

The drawings show an embodiment of the backflow prevention type suction cooling mechanism according to the present invention, and FIG. 1 is a schematic explanatory diagram;
Figure 2 is a side view of a two-wheeled motor vehicle showing an embodiment;
The figure is a longitudinal cross-sectional view of the main part, and FIG. 4 is a cross-sectional view of the check valve portion. 1...Engine, 2...Engine auxiliary equipment, 3...
Cooling section, 4... Exhaust system pipe, 5... Muffler, 6... Negative pressure generating section, 7... Sub-silencer, 8... Check valve, 9...
...cooling air flow conduit.

Claims (1)

[Claims] 1. A negative pressure generating section with a reduced cross-sectional area of the pipe is provided at an appropriate location of the engine exhaust system pipe, and the negative pressure generating section is connected to a system line that communicates with the engine body or its peripheral equipment, takes in air flow, and cools it. Backflow prevention, characterized in that the pipe is connected by a pipe, and the pipe is provided with a means for silencing the air flow in the pipe, and a check valve that stops the flow from flowing backward through the pipe from the negative pressure generating section. With suction cooling mechanism.