JP2515573Y2 - Engine intake introduction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of an intake system for an engine in consideration of improvement of a filling rate of intake air supplied into a combustion chamber of the engine.

(Prior Art) Generally, an intake system of an engine is, for example, the actual engine shovel 62-1309.
As disclosed in Japanese Patent Publication No. 29, a fresh air duct for taking in fresh air and a communication with the fresh air duct,
It is composed of an air cleaner for purifying fresh air and a carburetor connected to the air cleaner to supply air-fuel mixture to the combustion chamber side of the engine. The fresh air duct is provided with an opening at a position that prevents engine damage due to water entering the combustion chamber.

On the other hand, in recent years, attention has been paid to improving the charging efficiency of intake air, that is, supercharging the intake air into the combustion chamber to improve compression, as one means for increasing the output of the engine.
Specific supercharging means include a turbocharger that uses exhaust gas energy of the engine as a driving force, a supercharger that uses a compressor that is driven by the driving force of the engine, and the like, and their development has been advanced.
Incidentally, such means may be equipped with a water-cooled or air-cooled intercooler for the purpose of cooling the intake air that has been compressed and become high temperature to further improve the charging efficiency. The intercooler has an intercooler duct that extends to the front end of the vehicle body in the engine room and introduces outside air. When the vehicle is traveling, traveling air is introduced from the intercooler duct to cool the introduced air. It is designed to contribute to.

(Problems to be solved by the invention) However, in the above-mentioned structure, the amount of fresh air for supercharging is limited because it is introduced only from the inlet of the fresh air duct. . As for noise, the fresh air duct inlet is open in the engine room, so its length is short due to the layout in the engine room, and the noise is sufficiently attenuated in the duct to the outside of the vehicle body. It is difficult to effectively reduce the release amount of

On the other hand, when the vehicle is traveling at a high speed, a large amount of traveling air is introduced from the intercooler duct and is introduced in excess of the amount required to cool the high-temperature intake air generated by the supercharging means. There is air. That is, as shown in FIG. 5 and FIG. 6, the high speed utilization rate due to the vehicle speed when the vehicle is running and the wind speed on the rear side of the intercooler is as follows.

Vehicle speed utilization rate (%) = Intercooler rear wind speed (m / s) x 3.6
× 100 / vehicle speed (km / h) As shown in the graph in Fig. 6, in the high-speed range, the cooling air introduced into the intercooler increases with increasing vehicle speed, and cooling efficiency improves. However, the vehicle speed utilization rate decreases. That is, the amount of surplus air increases.

Therefore, the present invention pays attention to the running wind when this vehicle is running,
The purpose is to increase the amount of intake air introduced by allowing traveling air to be introduced into the fresh air duct.

(Means for Solving the Problems) Means taken by the present invention to achieve the above object are
It is premised that a fresh air duct that introduces intake air into the engine from an introduction port whose upstream end is open to the atmosphere and a traveling wind duct that introduces traveling wind of the vehicle into the vehicle are assumed. And, a communication passage for communicating the fresh air duct with the traveling wind duct at a position different from the introduction port of the fresh air duct, and an opening / closing arranged in the communication passage for communicating the communication passage only during high speed operation of the vehicle. A valve is provided.

(Operation) The operation of the present invention having the above-described configuration is such that the open / close valve is opened during high-speed operation of the vehicle, the communication passage is in the communication state, and a part of the traveling air flowing through the traveling air duct is supplied into the fresh air duct. As a result, the amount of intake air is increased and the filling rate of intake air is improved. On the other hand, a part of the noise emitted from the engine is guided into the traveling wind duct, and is attenuated while being transmitted through the traveling wind duct, so that the amount emitted to the outside of the vehicle body is reduced.

First Embodiment Next, a first embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 3, the intake air introducing device 1 in this example
Is located in the front part of the engine room, and mainly includes a fresh air duct 2, an intercooler duct (a traveling wind duct in the present invention) 3, a communication passage 4 and a communication passage opening / closing means 5.

Hereinafter, each member will be described with reference to FIGS. 1 and 2.

The fresh air duct 2 introduces air (fresh air) E that generates a mixture to be supplied into the combustion chamber of the engine, and extends in the vehicle width direction and has one end connected to an air cleaner (not shown). 2a and the main duct
The inlet duct 2b extends from 2a toward the front of the vehicle body and is supported by a first cross member F1 forming the front end of the vehicle body frame F, and has an inlet 2c opened at one end.

The intercooler duct 3 supplies cooling air (running wind) E ′ to an intercooler 6 for cooling intake air compressed by a supercharging means (turbocharger or the like) mounted on the engine.
Is introduced from the outside and is located below the fresh air duct 2 and extends in the vehicle body front-rear direction, and its rear end 3a is connected to the intercooler 6 and, on the other hand, the traveling wind introduction port 3b which is the front end. As shown in FIG. 3, it extends forward and opens near the grill at the front end of the vehicle body.

The communication passage 4, which is a feature of the present invention, connects the lower surface 2d of the main duct 2a of the fresh air duct 2 and the upper surface 3c of the intercooler duct 3 so as to communicate the air passages of both.

The communication passage opening / closing means 5 is provided at an upper portion of the communication passage 4 and is provided with an opening / closing flap 5b as a swingable semicircular opening / closing valve on a rotation shaft 5a in the vehicle longitudinal direction. The shape of the flap 5b matches the sectional shape of the communication passage 4. A coil spring 5c is wound around the rotary shaft 5a, and the opening / closing flap is closed by the coil spring 5c.
5b is urged in the direction of closing the communication passage 4. The urging force of the coil spring 5c is the fresh air duct 2
Negative pressure of air E flowing inside and intercooler duct 3
When the dynamic pressure of the air E'circulating inside exceeds a predetermined value, it is opened by both pressures. In the case of this example, since the opening / closing flap 5b is set to open the communication passage 4 at a vehicle speed of 40 km / h or more, the negative pressure in the fresh air duct 2 is 300 mmHg or more, and the dynamic pressure in the intercooler duct 3 is The negative force of the coil spring 5c is set so that the opening / closing flap 5b is swung by the pressure of about 350 mmHg so as to open at 50 mmHg or more.

Next, the operation of the present apparatus having the above configuration will be described.

First, when driving at low speed (40 km / h or less in this example),
Since the negative pressure of the air E flowing in the fresh air duct 2 and the dynamic pressure of the air E'flowing in the intercooler duct 3 have not reached a predetermined value, the opening / closing flap 5b causes the communication passage 4 to move due to the biasing force of the coil spring. The intake air supplied to the engine side is only the air E introduced into the main duct 2a from the outside air introduction port 2c through the inlet duct 2b. That is, the operating state is the same as the conventional one with the intake air amount. On the other hand, the air E'circulating in the intercooler duct 3 is all supplied to the intercooler 6 side (arrow A) because the opening / closing flap 5b is closed.
This contributes to the cooling of the intake air compressed by the supercharging means.

Next, when traveling at high speed (40 km / h or more), the negative pressure of the air E flowing through the fresh air duct 2 and the dynamic pressure of the air E ′ flowing through the intercooler duct 3 are equal to a predetermined value (350 m).
mHg), the opening / closing flap 5b is opened against the biasing force of the coil spring 5c, and a part of the air E'circulating in the intercooler duct 3 is supplied to the main duct 2a side through the communication passage 4 ( Arrow B). By this supply, the amount of intake air in the fresh air duct 2 is increased, and the filling rate of intake air into the combustion chamber is improved. At this time, the cooling air E'supplied to the intercooler 6 side has a sufficient amount required for cooling, and does not hinder the performance of the supercharging means. Further, the noise emitted from the engine is transmitted to the fresh air duct through the intake port, the air cleaner, etc., and a part of the noise enters the intercooler duct 3 through the communication passage 4. The noise is generated because the intercooler duct 3 has a long length, and
By the time it reaches 3b, it is attenuated and exhibits a sound deadening effect.

In addition to the control corresponding to the vehicle speed described above, when the engine speed is increased during idling (that is, when the engine is idling), high temperature air flows backward from the intercooler 6 side through the intercooler duct 3 (arrow C). ), But at that time,
Since the opening / closing flap 5b is closed, the hot air is not supplied from the fresh air duct 2 to the combustion chamber side, and the hot air does not cause overheating or knocking.

As described above, according to the configuration of this example, the traveling air can be introduced into the fresh air duct 2 with a simple configuration, and the amount of intake air introduced can be increased. It is also possible to reduce noise when traveling at high speed.

(Second Embodiment) In this embodiment, the communication passage opening / closing means 5 is different from that of the first embodiment described above. Therefore, only the difference will be described.

As shown in FIG. 4, the communication passage opening / closing means 5 in this example.
Is provided at the upper part of the communication passage 4 and is provided with a swingable open / close flap 5b on a rotary shaft 5a in the vehicle width direction. A signal from a vehicle speed sensor (not shown) is provided at one end 5d of the open / close flap 5b. An actuator 5e that is driven by a CPU that receives it is provided, and the opening / closing flap 5b can open and close the communication passage 4 by the operation of the actuator 5e. Incidentally, in the case of this example, the operation switching point of the actuator 5e is set to the vehicle speed of 40 km / h as in the case of the above-mentioned first example.

In the operation of this device with this configuration, as in the case of the first embodiment, the opening / closing flap 5b opens and closes the communication passage 4 at the vehicle speed of 40 km / h as a boundary, flows through the fresh air duct, and is supplied into the combustion chamber. We are trying to adjust the amount.

Therefore, in this example, it is easy to set the switching point of the opening / closing flap 5b, and it is possible to reliably switch the intake air amount at a predetermined value.

Although the intercooler duct is applied as the traveling wind duct of the above-described first and second embodiments, the present invention is not limited to this, and various outside air intake means can be adopted.

(Effect of the Invention) As described above, according to the present invention, the air flowing in the traveling wind duct is not introduced into the fresh air duct by shutting off the communication passage by the open / close valve during low speed operation of the vehicle. , A sufficient amount of air in this traveling wind duct is secured. Therefore, when this air is used for a cooling device such as an intercooler, its cooling performance can be sufficiently ensured. On the other hand, during high-speed operation of the vehicle, the on-off valve is opened, and the surplus of the running air flowing through the running air duct is introduced into the fresh air duct through the communication passage to increase the intake air amount, and thereby to the combustion chamber. The intake air filling rate is improved, and the engine output can be increased with a simple configuration. In addition, a part of the noise emitted from the engine is guided to the traveling wind duct through the fresh air duct, and is attenuated while being transmitted to the introduction port of the traveling wind duct to reduce the emission amount outside the vehicle body. It also has

[Brief description of drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view of the present apparatus, FIG. 2 is a perspective view thereof, and FIG. 3 is a side view thereof. FIG. 4 shows the first embodiment of the second embodiment of the present invention.
It is a figure of the same part as a figure. FIG. 5 is a diagram showing the relationship between the vehicle speed and the rear wind speed of the intercooler, and FIG. 6 is a diagram showing the relationship between the vehicle speed and the intercooler vehicle speed utilization rate. 1 ... Intake introduction device, 2 ... Fresh air duct, 3
…… Intercooler duct (running wind duct), 3b …… Running air inlet, 4 …… Communication passage, E …… New air, E ′ …… Running wind.

Claims (1)

(57) [Scope of utility model registration request] 1. A fresh air duct for introducing intake air into an engine from an inlet having an upstream end open to the atmosphere, and a running wind duct for introducing running wind of a vehicle into the vehicle, wherein the fresh air duct is introduced. A communication passage that communicates the fresh air duct and the traveling wind duct at a position different from the mouth, and an on-off valve that is disposed in the communication passage and that allows the communication passage to communicate only when the vehicle is operating at high speed are provided. An intake system for an engine, which is characterized in that