KR100189564B1 - Variable intake system and its control method in an automotive engine - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold mounted to an engine of an automobile, and in particular, to control an intake manifold configured to vary the length of a long / short in an intake manifold, the amount of fuel injection according to the pressure of the intake manifold detected using a vacuum sensor. The first process of starting the engine and the second process of determining the opening / closing angle of the throttle valve according to the running load of the engine after the engine is started so as to automatically vary the intake air according to the determined fuel injection amount. When the valve is opened or closed at a predetermined angle, the third process of determining the engine speed and the fourth process of controlling the fuel injection amount of the intake manifold according to the determined running load and the speed of the engine are variable. It relates to an intake system control device and a control method.

Description

Variable intake system control device and control method for automobile engine

1 is a longitudinal sectional view of a conventional general variable intake manifold,

2 is an output waveform diagram of FIG.

3 is a block diagram of a variable intake system control apparatus for an automobile engine according to the present invention;

4 is an output waveform diagram of FIG.

5 is a flowchart illustrating a method of controlling a variable intake system of an automobile engine according to the present invention.

* Explanation of symbols for main parts of the drawings

10: negative pressure source 20: negative pressure reservoir

30 one-way valve 40 solenoid valve

50: orifice 60: diaphragm

70: throttle valve

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold mounted to an engine of an automobile, and in particular, in controlling an intake air configured to vary the length of a long / short in an intake manifold, a fuel injection amount is determined according to the pressure of the intake manifold detected using a vacuum sensor. The present invention relates to a variable intake system control apparatus and a control method for an automobile engine capable of automatically varying the intake path according to the determined fuel injection amount.

In general, automobiles have a heat engine, or an engine, which is an internal combustion engine that converts thermal energy generated inside an engine by combustion of fuel into mechanical energy, and an intake manifold mounted to the engine includes a carburetor outlet and each cylinder. The intake hole is connected to distribute the mixer made from the carburetor evenly to each cylinder. It is usually made of cast iron. In the multi-cylinder engine, two adjacent intake holes are common, and the length between the carburetor and each cylinder intake hole is The larger the diameter of the intake manifold, the higher the suction efficiency. However, if the speed of the mixer is low, the flow rate at the highest rotational speed of the engine is usually because the mist-like fuel particles adhere to the walls of the intake manifold. It is designed not to be less than 2.5m / sec when operating at 70m / sec. Therefore, according to this, the inner diameter of the intake manifold is 25-35%.

On the other hand, the variable intake control system for controlling the intake of the intake manifold as described above, by adjusting the circuit of the air flow sucked by the control signal of the computer so that the maximum torque is generated according to the rotational speed of the engine, Set the target position of the sub valve according to the number of revolutions in advance, and if a difference occurs between the actual values, the difference is detected by the variable induction control valve position sensor and input to the computer. By operating the VIC valve drive motor, the circuit of air flow is regulated to match the actual value.

In the conventional variable intake manifold, as shown in FIG. 1, the separation wall 3 is formed in the inner intake port 2 of the intake manifold 1 in the same manner as the outer wall 4, and the separation wall 3 The on-off valve 5 is provided between the front end of the head) and the inwardly protruding end of the outer wall 4.

In the figure, reference numeral 6 denotes an inlet, 7 an outlet, and 8 an intake path.

In the conventional intake manifold configured as described above, first, clean air passing through an air cleaner (not shown) is supplied in the direction of the arrow below the intake manifold 1 at a low speed running of the engine at low speed, and is thus internally provided through the intake port 2. Flows into.

The air introduced in this way passes through the inlet 6 through the inlet 6 through a long flow through the passage between the separation wall 3 and the outer wall 4 and the intake passage 8 through the outlet 7. Supplied to the engine.

On the other hand, in the high speed travel, the air introduced into the intake port 2 by the opening and closing of the valve 5 is supplied to the engine through the outlet 7 in a short flow immediately passing through the intake path 8.

The variable operation of the air flow is made by the opening and closing of the on-off valve 5, the opening and closing operation as described above is automatically operated at the set value according to the low and high speed of the engine speed as shown in FIG. will be.

However, the conventional variable intake system as described above, by adjusting the circuit of the air flow sucked by the control signal of the computer to control the generation of the maximum torque in accordance with the rotational speed of the engine to take into consideration the running load of the engine. There is a problem that can not be precise control by detecting and controlling only the engine speed irrespective of the running load, thus reducing the efficiency of driving.

Accordingly, the present invention has been made to solve the above-mentioned problems of the related art. The present invention relates to the pressure of the intake manifold detected by using a vacuum sensor in controlling the intake passage configured to vary the length of the long / short in the intake manifold. It is an object of the present invention to provide a variable intake system control apparatus and a control method for an automobile engine that can automatically vary the intake air according to the determined fuel injection amount by determining the fuel injection amount accordingly.

The present invention for achieving the object as described above, the negative pressure source for forming the intake negative pressure of the engine, the negative pressure reservoir for receiving the intake negative pressure formed in the negative pressure source to maintain a constant intake negative pressure volume, stored in the negative pressure reservoir One-way valve for preventing the loss of intake negative pressure, solenoid valve for connecting or disconnecting the intake negative pressure of the negative pressure reservoir, orifice for preventing the solenoid valve from opening rapidly, and intake negative pressure connected through the solenoid valve It is characterized by consisting of a diaphragm for opening and closing the throttle valve by receiving a negative pressure of.

In addition, the present invention for achieving the above object, the first process for starting the engine, the second process for determining the opening and closing angle of the throttle valve according to the running load of the engine after starting the engine, the throttle valve is a predetermined angle or more And a third process of determining the engine speed when the engine is opened and closed, and a fourth process of controlling the fuel injection amount of the intake manifold according to the determined running load and the engine speed of the engine.

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

The variable intake system control apparatus for an automobile engine according to the present invention includes a negative pressure source 10 for forming an intake negative pressure of the engine, as shown in FIG. A negative pressure reservoir 20 which receives the intake negative pressure formed in the negative pressure source 10 and maintains a constant intake negative pressure volume; A one-way valve 30 for preventing a loss of intake negative pressure stored in the negative pressure reservoir 20; A solenoid valve 40 for connecting or disconnecting the intake negative pressure of the negative pressure reservoir 20; An orifice (50) for preventing the solenoid valve (40) from being opened and closed abruptly; The diaphragm 60 opens and closes the throttle valve 70 by receiving a negative pressure of the intake negative pressure connected through the solenoid valve 40.

Referring to the operation and effect of the present invention configured as described above in detail.

The present invention is to control the intake when the variable intake system function is selected to improve the performance of the engine at medium / high speed, the coolant temperature of the engine is a certain temperature (for example about 20 ℃ or more and the air sucked into the intake manifold If the engine is started at a certain temperature (e.g. about 20 ° C) or more at a determined speed (e.g. about 40 km / hour) or more, the electronic control module (not shown) When a valve open / close command is transmitted to the solenoid valve 40, the intake negative pressure generated at the load source 10 is transmitted to the negative pressure reservoir 20 through the one-way valve 30.

After the intake negative pressure formed in the load source 10 is transferred to the negative pressure reservoir 20 through the one-way valve 30, 12 V is applied to the solenoid (not shown) through the solenoid valve 40. At this time, the intake negative pressure in the negative pressure reservoir 20 operates the diaphragm 60 to open the throttle valve 70.

When the throttle valve 70 is opened or closed by a predetermined angle (for example, about 25-3% to 25%) by determining the opening and closing angle of the throttle valve 70 that is opened and closed according to the running load of the engine after starting the engine as described above. By determining the engine speed, if the engine speed is equal to or greater than a predetermined speed (for example, about 1800 to 2000 RPM or 4800 to 5000 RPM), the fuel injection amount of the intake manifold is controlled according to the determined running load and the rotation speed of the engine.

Here, the fuel injection quantity can be calculated | required by following Formula (Equation 1).

Fuel injection quantity = engine speed × engine negative pressure × volumetric efficiency

= RPM × MAP × VE. (Equation 1)

On the other hand, when the operation of the intake manifold according to the running load and the number of revolutions of the engine is shown in a waveform diagram as shown in Figure 4, the opening and closing angle of the throttle valve 70 is within a certain angle, that is, Θ1 throttle valve opening and closing angle Θ1- It is in the HΘ1 range, and the engine speed is operated above or below a certain speed, that is, within the R1 + HR1 engine speed R1 or R2 engine speed R2-HR2 range.

A first process (100) of starting the engine as shown in FIG. A second step 200 of determining an opening / closing angle of the throttle valve according to the running load of the engine after starting the engine; A third process 300 for determining the rotation speed of the engine when the throttle valve is opened or closed by a predetermined angle; In operation S400, the fuel injection amount of the intake manifold is sequentially controlled according to the determined driving load and the rotation speed of the engine.

The first step (100) comprises a first step (101) of determining whether a variable intake system control function has been selected; A second step (102) of determining whether the coolant temperature of the engine is above a predetermined temperature (T1) when the variable intake system control function is selected; A third step (103) of determining whether the air temperature drawn into the intake manifold is above the predetermined temperature (T2) when the coolant temperature of the engine is above the predetermined temperature (T1); When the air temperature sucked into the intake manifold is equal to or higher than the predetermined temperature T2, the operation is sequentially performed in a fourth step 104 of determining whether the speed of the vehicle is equal to or higher than the predetermined speed V1.

The second step (200) comprises a first step (201) of determining whether the variable intake system is turned on after the engine is started; A second step 202 of determining whether the opening / closing angle of the throttle valve according to the running load of the engine is equal to or less than a certain angle Θ1 when the variable intake system is not turned on; On the other hand, when the variable intake system is turned on, the operation of the throttle valve according to the running load of the engine is sequentially performed in the third step 203 for determining whether the opening / closing angle is less than or equal to the predetermined angle θ1-HΘ1.

The third process (300) includes a first step (301) of determining whether the variable intake system is turned on when the throttle valve is opened or closed over a predetermined angle; A second step 302 of determining whether the engine speed is less than the constant speed R1 when the variable intake system is not turned on; On the other hand, when the variable intake system is turned on, a third step 303 for determining whether the engine speed exceeds a predetermined speed R1 + HR1; A fourth step 304 of primarily determining the engine speed and then determining whether the variable intake system is turned on for fine control of the engine; If the variable intake system is not turned on, a fifth step 305 of determining whether the engine speed is greater than the constant speed R2; On the other hand, when the variable intake system is turned on, operation proceeds sequentially to a sixth step 306 of determining whether the engine speed exceeds a certain speed R2-HR2.

The fourth process 400 includes a first step 401 of determining whether the variable intake system is turned on when the engine is not started; If the variable intake system is turned on, resetting the variable intake system flag to zero; A third step 403 of determining whether the variable intake system is turned on when the engine is started; A fourth step 404 of setting the variable intake system flag to 1 if the variable intake system is not turned on; The operation is sequentially performed in a fifth step 405 of controlling the fuel injection amount of the intake manifold according to the determined running load and the rotation speed of the engine.

As described in detail above, the present invention provides a fuel injection amount determined by determining the fuel injection amount according to the pressure of the intake manifold detected using a vacuum sensor in controlling the intake passage configured to have different lengths / shorts in the intake manifold. According to the present invention, the intake air can be automatically varied, and the engine speed can be precisely controlled by sensing the number of revolutions of the engine several times, thereby improving the efficiency of the intake stroke at engine start.

Claims (6)

A negative pressure source 10 for forming an intake negative pressure of the engine; A negative pressure reservoir 20 which receives the intake negative pressure formed in the negative pressure source 10 and maintains a constant intake negative pressure volume; A one-way valve 30 for preventing a loss of intake negative pressure stored in the negative pressure reservoir 20; A solenoid valve 40 for connecting or disconnecting the intake negative pressure of the negative pressure reservoir 20; An orifice (50) for preventing the solenoid valve (40) from being opened and closed abruptly; A variable intake system control apparatus for an automobile engine, characterized in that the diaphragm (6) for opening and closing the throttle valve (70) in response to the negative pressure of the intake negative pressure connected through the solenoid valve (40). A first step (100) of starting the engine; A second step 200 of determining an opening / closing angle of the throttle valve according to the running load of the engine after starting the engine; A third process 300 for determining the rotation speed of the engine when the throttle valve is opened or closed by a predetermined angle; And a fourth step (400) of controlling the fuel injection amount of the intake manifold according to the determined driving load and the rotational speed of the engine. The method of claim 2, wherein the first process (100) comprises: a first step (101) of determining whether a variable intake system control function has been selected; A second step (102) of determining whether the coolant temperature of the engine is above a predetermined temperature (T1) when the variable intake system control function is selected; A third step (103) of determining whether the air temperature drawn into the intake manifold is above the predetermined temperature (T2) when the coolant temperature of the engine is above the predetermined temperature (T1); Variable air intake system of an automobile engine, characterized in that the operation in the fourth step (104) to determine whether the speed of the vehicle is above a certain speed (V1) when the air temperature sucked into the intake manifold is above the predetermined temperature (T2). Control method. 3. The method of claim 2, wherein the second step (200) comprises: a first step (201) of determining whether the variable intake system is turned on after the engine is started; A second step 202 of determining whether the opening / closing angle of the throttle valve according to the running load of the engine is equal to or less than a certain angle Θ1 when the variable intake system is not turned on; On the other hand, when the variable intake system is turned on, the automobile engine is sequentially operated in a third step 203 for determining whether the opening / closing angle of the throttle valve according to the running load of the engine is equal to or less than a predetermined angle (θ1-HΘ1). Variable intake system control method. 3. The method of claim 2, wherein the third process (300) comprises: a first step (301) of determining whether the variable intake system is turned on when the throttle valve is opened or closed over a predetermined angle; A second step 302 of determining whether the engine speed is less than the constant speed R1 when the variable intake system is not turned on; On the other hand, when the variable intake system is turned on, a third step 303 for determining whether the engine speed exceeds a predetermined speed R1 + HR1; A fourth step 304 of primarily determining the engine speed and then determining whether the variable intake system is turned on for fine control of the engine; If the variable intake system is not turned on, a fifth step 305 of determining whether the engine speed is greater than the constant speed R2; On the other hand, when the variable intake system is turned on, the variable intake system control method for a car engine, characterized in that the operation in the sixth step 306 to determine whether the engine speed exceeds a predetermined speed (R2-HR2) . The method of claim 2, wherein the fourth process (400) comprises: a first step (401) of determining whether the variable intake system is turned on when the engine is not started; If the variable intake system is turned on, resetting the variable intake system flag to zero; A third step 403 of determining whether the variable intake system is turned on when the engine is started; A fourth step 404 of setting the variable intake system flag to 1 if the variable intake system is not turned on; And a fifth step (405) of controlling the fuel injection amount of the intake manifold according to the determined running load and the rotational speed of the engine.