KR100222521B1 - Intake system and its control method for internal combustion engines - Google Patents

Abstract

A throttle body (2) having a throttle valve for regulating the amount of air as a means for obtaining a large and uniform torque in the full speed range of the engine and producing a maximum output and enabling lean combustion, and the throttle body described above. A surge tank 4 for distributing and supplying air to each combustion chamber by receiving intake air from the intake air, a cylinder head 8 having an exhaust port and an intake port 38, and the intake port 38 and the surge tank described above. (4) to connect the low-speed intake pipes (6) for supplying air to the combustion chamber 40, the throttle body (2) and the intake port (38) to supply air to the combustion chamber (40) The high speed intake pipes 14 and the cylindrical valve 16 installed in the high speed intake pipe so as to supply air to the combustion chamber only at the high speed of the engine region and the cylindrical valve are controlled by the electronic control unit. Including the strapping motor 18 That of the engine intake system.

Description

Intake system and intake control method of internal combustion engine

1 is a perspective view of an intake system according to the present invention.

2 is a diagram showing a temporary example of an intake control valve according to the present invention.

3 is a view showing another embodiment of an intake control valve according to the present invention.

4 is a side cross-sectional view of the intake system according to the present invention.

5 is a view for explaining the intake flow at high speed of the intake system according to the present invention.

Figure 6 is a view for explaining the intake flow at low and medium speed of the intake system according to the present invention.

7 shows means for controlling fuel flow to the intake port according to the present invention.

8 is a block diagram for explaining the intake control method according to the present invention.

9 is an operation diagram for explaining the intake control of the intake control system according to the present invention.

* Explanation of symbols for main parts of the drawings

2: Throttle Body 4: Surge Tank

6: low speed intake pipe 8: cylinder head

10: bypass pipe 14: high speed intake pipe

16: cylindrical valve 18: stepping motor

20: channel 24: actuator

38: intake port 40: combustion chamber

42: fuel injector 48: spark plug

50: dividing wall

The present invention relates to an intake system and an intake control method of an internal combustion engine, and more particularly, it is possible to obtain a uniform output in a low, medium, and high speed region, and in particular, to prevent a decrease in output when entering a high speed region, It relates to an intake system capable of realizing.

The output of the engine depends on the structure and shape of the intake pipes connecting between the surge tank and the combustion chamber, because the filling efficiency of the intake air can be increased by changing the structure of the intake pipe.

In the case of a high-performance engine, two intake pipes are installed for one cylinder. One intake pipe allows air to flow only in a high speed region, and the other intake pipe has air flow in a low and high speed region. .

In this way, the engine equipped with two intake pipes for one cylinder is provided with air adjusting means for selecting these intake pipes according to the speed range of the engine.

The engine employing such an air intake variable system, the intake pipe separated into the low speed intake pipe and the high speed intake pipe can be installed in a structure that can minimize the resistance of the air flow can be improved efficiency.

However, even if the engine is provided with a means for additionally supplying intake air at high speed according to the speed range, the additional air supply method is important in the design of the intake cylinder because the efficiency is limited by the additional supply method of air. .

In addition, such an intake system should have four structures capable of realizing lean combustion, and in general, there is a problem that the ignition speed does not proceed rapidly when lean combustion is performed.

The present invention has been invented in view of the problems of the prior art as described above, and an object of the present invention is to increase the ignition speed with lean combustion and to obtain the maximum output in the full speed range of the engine, It is to provide an intake system of the internal combustion engine that can speed up.

In order to realize the object of the present invention as described above, a throttle body having a throttle valve for adjusting the amount of air, a surge tank for distributing and supplying air to each combustion chamber by receiving intake air from the throttle body, and exhaust A cylinder head having a port and an intake port, low-speed intake pipes connecting the intake port and the surge tank to supply air to the combustion chamber, and connecting the throttle body and the intake port to supply air to the combustion chamber A high speed intake pipe, a cylindrical valve installed in the high speed intake pipe so as to supply air to the combustion chamber only at a high speed in the engine region, and a strapping motor controlling the cylindrical valve by an electronic control unit. An intake system of an internal combustion engine is provided.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is an external perspective view of an intake system according to the present invention, which is connected to an air cleaner (not shown) to receive air and has a throttle body having a throttle valve plate for controlling and supplying substantially supplied air into a combustion chamber. 2) and a surge tank 4 which communicates with this throttle body to supply air to each combustion chamber.

The surge tank 4 is connected to the cylinder head 8 by low speed intake pipes 6 which induce air into the combustion chamber at low speed.

In this embodiment, four-cylinder engines are shown, so four low speed intake pipes are shown.

The cylindrical valve casing 12 is fixedly communicated with the bypass conduit 10 leading from the throttle body 2.

The valve casing 12 communicates with the cylinder head 8 through the high speed intake pipes 14 so that additional air can be supplied in the high speed region.

The low speed intake pipe and the high speed intake pipe are connected to one intake port, respectively, in connection to the corresponding combustion chamber.

The inner diameter of the low speed intake pipes 6 is smaller than the inner diameter of the high speed intake pipes 14 and has a long length, which increases volumetric efficiency by allowing air to flow quickly with high inertia. This is to improve the combustion efficiency.

And the high speed intake pipes 14 are made larger than the inner diameter of the low speed intake pipes and the length thereof is shortened to minimize the quick response and the frictional resistance of the intake air in the high speed area.

Inside the cylindrical valve casing 12, as shown in FIG. 2, the cylindrical valve 16 is rotatably positioned and rotated 180 degrees by a stepping motor 18 controlled by the electronic control unit (ECU). It has a rotatable structure.

The cylindrical valve 16 has a constant width in the longitudinal direction and the channel 20 is formed, the rotational axis of the stepping motor 18 is connected to one end of the cylindrical valve 16 and the opening (opposite side) 22 is formed to receive the air flowing from the bypass pipe (10).

With this structure, when the cylindrical valve 16 is rotated so that the channel 22 is positioned toward the high speed intake pipes 14, additional air is supplied, and the channel 22 does not communicate with the high speed intake pipes. Then no additional supply is made.

3 is a view showing another embodiment of the cylindrical valve according to the present invention. In the first embodiment, the cylindrical valve 16 is rotated as a stamping motor. The rack gear 26 can be linearly moved by the actuator 24 acting by the same, and the pinion 28 connected to the cylindrical valve 16 is geared to the rack gear 26 described above.

In addition, in the first embodiment, the air flow path of the cylindrical valve 16 is illustrated in the longitudinally cut channel, but in the second embodiment, passages 30 and 32 that can communicate with each of the high speed intake pipes, respectively. , 34,36).

4 is a side cross-sectional view of the intake system according to the present invention, in which the surge tank 4 communicates with the intake port 38 of the cylinder head 8 to the intake port 38 of the cylinder head 8 so that the air flows through the combustion chamber. (40) can be supplied.

The fuel injector 42 controlled by the electronic control unit is provided at the inlet side of the intake port 38. The intake valve 44 for opening and closing the intake port and the exhaust valve for opening and closing the exhaust port are shown. (46) is shown and shown together.

FIG. 5 shows a phase in which air can be additionally supplied to the combustion chamber when the speed range of the engine is high speed, and FIG. 6 shows a state in which air is blocked from flowing to the high speed intake pipe at low speed.

7 is a cross-sectional view of the intake port 38 according to the present invention. The intake port 38 communicating with the combustion chamber 40 is divided into two types, and the fuel injector 42 has two intake ports. It is possible to inject fuel from the central part.

The fuel injected into the fuel injector 42 is guided around the spark plug 48 so that a dark mixer can exist around the spark plug in this embodiment. ) So that fuel injected from the fuel injector 42 can flow to the spark plug 48 side.

In the intake system of the present invention, the engine allows the high speed intake pipes 14 to be blocked in the low speed region so that air can flow to the low speed intake pipes 6, and in the low speed region, as shown in FIG. State is achieved.

As the engine enters the high speed region, the stamping motor 18 is driven to rotate the cylindrical valve 16 so that the cylindrical valve and the high speed intake pipe 14 communicate with each other as shown in FIG. 5. Air flows through all the intake pipes.

In the intake control method of the intake system, as shown in FIG. 8, signals from the crank angle sensor S1, the air flow sensor S2, and the throttle valve opening sensor S3 are rotated by the rotational speed detection unit 52, The air amount detecting unit 54 and the opening degree value detecting unit 56 are input, and the values of these detecting units are transferred to the calculating unit 58 to realize the stepping motor 18.

That is, as shown in FIG. 9, in the first step 100, it is determined whether the engine speed is greater than 3800 rpm. If the engine speed is smaller than the comparison value, the motor is not driven. It is determined whether the opening value of the throttle valve is greater than 47 degrees at.

If the value determined in the second step 110 is smaller than the comparison value, the motor is not driven. If the value is greater than the comparison value, the switch 60 is turned on in the third step 120 and the fourth step 130 is performed. Will drive the stepping motor 18.

When the stepping motor 18 is driven by this control method, the cylindrical valve 16 is rotated to be in the state of FIG. 5 or 6, and the additional air flowing into the bypass pipe 10 is transferred to the combustion chamber at high speed. It will be supplied and cut off at low speed.

As described above, the intake system according to the present invention supplies air to the combustion chamber through a low-speed intake pipe having a small diameter and a long length at a low speed, so that the speed of intake is increased, thereby increasing volumetric efficiency and improving combustion efficiency. .

At high speeds, additional air is supplied to the intake pipe having a shorter diameter and a larger diameter, thereby minimizing the flow resistance of the intake air.

Such intake control can obtain a large torque uniformly at low, medium and high speeds, and can produce maximum output power, thereby improving acceleration and runability at high speeds.

In addition, since the fuel injected from the fuel injector forms a dark mixer around the spark plug, the ignition can be enabled even in the lean region air-fuel ratio (17-23: 1), thereby improving fuel economy.

Claims (4)

In an internal combustion engine comprising a throttle body having a throttle valve for adjusting the amount of air, and a surge tank for distributing and supplying air to each combustion chamber by receiving intake air from the throttle body, and a cylinder head having an exhaust port and an intake port. (a) a low speed intake pipe connecting the intake port and the surge tank to supply air to the combustion chamber; (b) a high speed intake pipe connecting the intake port and the throttle body to supply air to the combustion chamber; (c) a cylindrical valve installed in the high speed intake pipe to supply air to the combustion chamber only when the engine region is high speed, wherein the cylindrical valve includes a channel communicating with the high speed intake pipe; And (d) an actuator for controlling the cylindrical valve according to the negative pressure of the engine. The intake system of an internal combustion engine according to claim 1, wherein a separation wall is provided at the intake port to guide fuel injected from the fuel injector to the spark plug side. A first step of determining whether the rotation speed signal is greater than 3800 rpm from a crank angle sensor; and a second step of determining whether the opening angle of the throttle valve is greater than 47 degrees when the comparison value of the first step is large; And a fourth step of driving the stepping motor by switching on and a third step of turning on the switch when the second step is satisfied. 4. The intake control method according to claim 3, wherein the driving of the stepping motor is stopped when the engine speed is 3800 rpm or less in the first step.