JPH08218904A - Intake air quantity control device for internal combustion engine - Google Patents

Abstract

PURPOSE: To reduce the load torque to be applied to a throttle vale so as to lower the rated output of a motor, and to downsize a motor. CONSTITUTION: An intake air passage passing through a throttle body 1 is formed of a first intake air passage 2 and a second intake air passage 3, and single throttle valve shaft 4, which is supported by the throttle body 1 freely to be turned, crosses the first intake air passage 2 and the second intake air passage 3. A first throttle valve 5 for controlling opening of the first intake air passage 2 and a second throttle valve 6 for controlling opening of the second intake air passage 3 are respectively fitted to the throttle valve shaft 4. Rotation of a motor 24 to be rotated in response to the output signal from an ECU 30 is given to the throttle valve shaft 4, and the first throttle valve 5 controls opening of the first intake air passage 2 and the second throttle valve 6 controls opening of the second intake air passage 3 with the rotation of the throttle valve shaft 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake air amount control device for controlling an intake air amount supplied to a combustion chamber of an internal combustion engine by means of a throttle valve arranged in an intake passage of a throttle body. In particular, the present invention relates to a throttle valve that controls the intake air amount operated by an electrically driven motor.

[0002]

2. Description of the Related Art A conventional intake air amount control device for an internal combustion engine will be described with reference to FIGS. FIG. 4 is a longitudinal sectional view of a main part of a conventional intake air amount control apparatus for an internal combustion engine, and FIG.
FIG. 6 is a system diagram showing a state in which the intake air amount control device shown in FIG. 4 is assembled to an internal combustion engine. Reference numeral 20 denotes a throttle body having a single intake passage 21 penetrating the inside thereof, and a throttle valve shaft 22 is disposed in the intake passage 21 so as to traverse the both ends of the throttle valve shaft 22. Is rotatably supported by the throttle body 20. A throttle valve 23 opens and closes the intake passage 21 and is attached to the throttle valve shaft 22. That is, when the throttle valve shaft 22 rotates, the intake passage 21
Is controlled by the throttle valve 23. Reference numeral 24 denotes a motor arranged on the right end 20A of the throttle body 20. The rotation of the motor 24 is the first throttle valve lever arranged at the right end of the throttle valve shaft 22 from the motor lever 24A via the transmission means 25. 23A. On the other hand, a monitoring throttle valve opening sensor 25 is arranged on the left end 20B of the throttle body 20, and the rotation of the throttle valve shaft 22 is controlled by the second throttle. It is applied via the valve lever 23B and the transmission means 26. The monitoring throttle valve opening sensor 25 detects the opening position state and acceleration / deceleration state of the throttle valve 23 driven by the motor 24, and outputs an electric signal to an electronic control unit described later. It is to confirm whether or not the valve 23 operates normally.

Then, an electric signal is input to the motor 24 as follows, and the motor 24 is rotationally driven. Reference numeral 27 denotes an accelerator pedal (or an accelerator grip) which is operated by the driver's will. The operation amount of the accelerator pedal 27 is an accelerator pedal sensor 29 (this is an angle sensor, A stroke sensor or the like) is mechanically input, the operation amount is converted into an electric signal by an accelerator pedal sensor 29, and the electric signal is output to an electronic control unit 30 (hereinafter referred to as ECU). When an electric signal from the accelerator pedal sensor 29 is input to the ECU 30, the digital signal directly passes through the input circuit and the analog signal is digitally converted by the A / D converter and then input to the microcomputer. It
Then, the microcomputer arithmetically processes the input signal and outputs an electric signal corresponding to the operation of the accelerator pedal 27 to the motor 24 through the output circuit.

According to the above, the motor 24 imparts the rotation in response to the operation of the accelerator pedal 29 to the first throttle valve lever 23A via the motor lever 24A and the transmission means 25, whereby the throttle valve 23 is controlled to the accelerator pedal. Pedal 29
It is possible to obtain the throttle valve opening degree according to the operation of
The air controlled by 3 is supplied into the combustion chamber of the internal combustion engine via an intake pipe described later. The above-described monitoring throttle valve opening sensor 25 monitors that the motor 24 is normally driven to rotate by an electric signal output from the ECU 30, and the throttle valve shaft 22 and the throttle valve 23 are normally operated (rotated). Play a role.

The throttle body 20 including these motors 24 is incorporated in the internal combustion engine as follows. Figure 5
In the following, reference numeral 31 denotes an internal combustion engine, which is a cylinder head 33 connected to the upper surface of a cylinder block 32.
An intake port 35 that communicates with the combustion chamber 34 and an exhaust port 36 are formed therein, and an intake pipe 38 having a fuel injection valve 37 is connected to the intake port 35 that opens to the side surface of the cylinder head 33. The throttle body 20 having the motor 24 is connected to the upstream side of the intake pipe 38, and the air cleaner 39 is further connected to the upstream side of the throttle body 20. Therefore, the amount of air flowing from the air cleaner 39 is controlled by the throttle valve 23, and is supplied into the combustion chamber 34 via the intake pipe 38 and the intake port 35. On the other hand, the fuel in the fuel tank 40 is pressurized by the fuel pump 41 and supplied to the fuel injection valve 37 through the fuel distribution pipe 42. The fuel injection valve 37 is injected by the valve opening signal from the ECU 30. By opening the holes, the desired fuel under pressure is injected and supplied into the combustion chamber 34 through the intake pipe 38 and the intake port 35.

[0006]

The conventional intake air amount control system for an internal combustion engine has the following problems.
During the rapid acceleration operation or the gradual acceleration operation of the engine in which the throttle valve 23 continuously opens the intake passage 21, torque in the closing direction, that is, load torque acts on the throttle valve 23. This load torque is formed by the throttle valve 23 between the upper surface of the throttle valve 23 and the intake passage 21 when the intake flow flowing in the intake passage 21 flows down from the upstream side of the throttle valve 23 to the downstream side. It is known that the surface pressure distribution on the upper surface of the throttle valve 23 becomes non-uniform due to the change of the projected area.
Further, the relationship between the diameter of the intake passage 21 and the load torque is as follows.
It is known that the load torque increases (increases) as the diameter of 1 increases. Explaining a concrete example with reference to FIG. 2, when the diameter of the intake passage 21 is 58 mm and the throttle valve 23 is fully closed, the inside of the intake passage 21 downstream of the throttle valve 23 is-
With a negative pressure of 700 mmHg applied, the throttle valve 23 is rapidly opened within 1 second from fully closed to fully opened.
Load torques of gf and Cm are generated. (Indicated by a chain line in FIG. 2.) On the other hand, under the same conditions as above,
When the throttle valve 23 is slowly opened from fully closed to fully open over 10 seconds or more, a load torque of 1.1 Kgf, Cm is generated at an intermediate opening degree of the throttle valve 23 near 55 degrees opening. (Indicated by a dotted line in FIG. 2.) And, as described above, the fact that a large load torque acts on the throttle valve requires an increase in the required torque of the motor, which increases the size of the motor. This is not preferable because the power consumption increases. Among them, an increase in size of the motor makes it difficult to mount and store it in a limited space in the bonnet such as an automobile, and increases the weight, which is not preferable. In addition, the increase in power consumption is not preferable in the case where the electric capacity is almost fixed and the electric capacity cannot be increased without limitation as in an automobile.

The present invention has been made in view of the above problems,
By reducing the load torque acting on the throttle valve,
The purpose is to reduce the rated output of the motor and thus reduce the size of the motor.

[0008]

According to the present invention, the above-mentioned problem is solved by opening and closing the intake passage passing through the throttle body with a throttle valve attached to a throttle valve shaft rotatably supported by the throttle body. An intake air amount in the internal combustion engine that is controlled, and a motor that applies a rotational force to the throttle valve shaft is provided on the throttle valve shaft in response to an electric signal output from the electronic control unit and the rotation of the motor is applied to the throttle valve shaft. In the control device, the throttle body is provided with a first intake passage and a second intake passage penetrating therethrough, and a single throttle valve shaft traversing the first intake passage and the second intake passage is rotatable. And a second throttle valve for opening and closing the first intake passage and a second throttle valve for opening and closing the second intake passage are attached to the throttle valve shaft, and the throttle valve shaft is provided with a motor of the motor. By giving rotation It is made.

[0009]

The intake amount required by the internal combustion engine is guaranteed by the total intake amount of the intake amount supplied from the first intake passage and the intake amount supplied from the second intake passage. On the other hand, the diameter of each intake passage of the first intake passage and the second intake passage can be made smaller than the diameter of the conventional intake passage having a single intake passage. According to this, in the first throttle valve of the first intake passage, Both the load torque applied and the load torque applied to the second throttle valve in the second intake passage can be reduced. Therefore, the total load torque of these is reduced, so that the rated output of the motor can be reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an intake air amount control device for an internal combustion engine according to the present invention will be described below with reference to FIG. The same reference numerals are used for the same structural parts as in FIG. Reference numeral 1 denotes a throttle body having a first intake passage 2 and a second intake passage 3 penetrating therethrough, and the first intake passage 2 and the second intake passage 3 are formed in parallel. 4 is a single throttle valve shaft,
The center of the first intake passage 2 and the second intake passage 3 is crossed, and both ends thereof are rotatably supported by the throttle body 1. Reference numeral 5 is a first throttle valve that controls the opening of the first intake passage 2, and a second throttle valve 6 that is attached to the throttle valve shaft 4 and that controls the opening of the second intake passage 3 is also the throttle valve shaft 4. Be attached to. Therefore, when the throttle valve shaft 4 rotates, the first throttle valve 5 and the second throttle valve 6 rotate synchronously to open and close the first intake passage 2 and the second intake passage 3. The first throttle valve lever 23A arranged at the right end of the throttle valve shaft 4 and the motor lever 24A attached to the output shaft 24B of the motor 24 arranged on the right end 20A of the throttle body 1 are the transmission means. They are mechanically connected by 25. The transmission means 25 may be one that can transmit the rotational force on one side to the rotation on the other side, like a linkage. In addition, the monitoring throttle valve opening sensor 25 arranged on the left end 20B of the throttle body 1 includes a second throttle valve lever 23B arranged at the left end of the throttle valve shaft 4 and a transmission means 26.
The rotation of the throttle valve shaft 4 is imparted via the.

Next, the operation will be described. When the driver depresses and operates the accelerator pedal 27 according to his / her will, this operation amount is mechanically input to the accelerator pedal sensor 29 through the transmission means 28, and this operation amount is converted into an electric signal by the accelerator pedal sensor 29. The electric signal is converted and output to the ECU 30. And EC
In U30, an electric signal corresponding to the operation of the accelerator pedal 27 is output to the motor 24 through the output circuit. According to the above, the motor 24 imparts rotation according to the operation of the accelerator pedal 29 to the throttle valve lever 23A and the throttle valve shaft 4 via the output shaft 8A, the motor lever 9, and the transmission means 25. When the throttle valve shaft 4 rotates in response to the rotation of the motor 24, the first throttle valve 5 controls the opening of the first intake passage 2 and the second throttle valve 6 in response to the rotation.
Is for controlling the opening of the second intake passage 3 according to the rotation thereof. Therefore, the intake air amount controlled by the first throttle valve 5 is supplied from the first intake passage 2 into the combustion chamber 34, and
The intake amount controlled by the second throttle valve 6 is supplied from the intake passage 3 into the combustion chamber 34. That is, the intake air amount supplied from the first intake passage 2 and the intake air amount supplied from the second intake passage 3 are supplied into the combustion chamber 34.

Here, in the present invention, as described above, the intake passage is replaced with the conventional single intake passage, and two intake passages, the first intake passage 2 and the second intake passage 3, are provided. It was According to the above, the diameter of the first intake passage 2 and the diameter of the second intake passage 3 can be made smaller than the diameter of the conventional single intake passage. That is, to give an example, in the case where the diameter of the intake passage is set to 58 mm when the conventional single intake passage is used, the present invention using two intake passages is used. The diameter of each of the first intake passage 2 and the second intake passage 3 can be set to 40 mm. With this setting, the opening area is 2,642 mm @ 2 when the intake passage diameter is 58 mm, and when two intake passage diameters of 40 mm are used, the total opening area is 2,514 mm @ 2 (1, 257 mm2 x 2 pieces = 2,514 mm2), the opening area of which is reduced by about 5%, but the diameter of the intake passage was originally set with a sufficient margin for the fully open intake amount required by the internal combustion engine. Therefore, the slight decrease in the opening area does not pose any problem, and the first intake passage 2 and the second intake passage 3 having the intake passage diameter of 40 mm can be used.

On the other hand, the experimental result of the load torque of the throttle valve when the diameter of the intake passage is set to 40 mm is shown in FIG.
Shown in. The conditions in such an experiment are the same as the conditions in which the experiment of FIG. 2 was performed, and when the throttle valve is fully closed,
A negative pressure of -700 mmHg is applied to the intake passage on the downstream side of the throttle valve, and in this state, the throttle valve is rapidly opened within 1 second from fully closed to fully open, and the throttle valve is opened for 10 seconds or more. It was performed during the time of slowly opening from the fully closed to the fully open. From the above experimental results,
When the throttle valve is rapidly opened, a load torque of 1.1 Kgf, Cm is generated at an intermediate opening degree near the 55 degree opening degree of the throttle valve.
(Indicated by the one-dot chain line in FIG. 3.) When the throttle valve is slowly opened, a load torque of 0.4 Kgf, Cm is generated at an intermediate opening degree near the 55 degree opening of the throttle valve. (Indicated by a dotted line in FIG. 3.) From the above experimental results,
In the case of the intake passage having a diameter of 40 mm, a maximum load torque of 1.1 kgf and Cm is generated when the throttle valve is rapidly opened. In the present invention, since the first intake passage 2 and the second intake passage 3 having the diameter of the intake passage of 40 mm are provided, the first throttle valve 5 has a maximum of 1 when the throttle valve is rapidly opened. .1K
A load torque of gf, Cm acts, while a load torque of 1.1 kgf, Cm at the maximum acts on the second throttle valve 6. Therefore, a load torque of 2.2 Kgf, Cm, which is the sum of the load torques, acts on the throttle valve shaft 4. According to the above, the maximum load torque generated in the present invention is compared with the maximum load torque 3 Kgf, Cm generated in the conventional intake air amount control device using the single intake passage having the diameter of the intake passage of 58 mm. It was able to be reduced to 2.2 Kgf and Cm.

According to the fact that the load torque acting on the throttle valve can be reduced in this way, the throttle valve shaft including the throttle valve can be rotated by reducing the rated output of the motor 24. According to the above, it is possible to reduce the size of the motor and save the current consumption of the motor.

[0015]

As described above, according to the intake air amount control apparatus for the internal combustion engine of the present invention, the first throttle body is provided.
A first throttle valve for opening and closing the first intake passage and a second throttle valve for controlling the opening and closing of the first intake passage on a single throttle valve shaft that crosses the intake passage and the second intake passage. Since the intake passages are arranged, the diameter of each intake passage can be made smaller than the diameter of the conventional intake passage that is configured with a single intake passage, which reduces the load torque acting on the throttle valve. is there. The reduction of the load torque makes it possible to reduce the rated output of the motor, so that the motor can be downsized and the current consumption can be saved.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of an intake air amount control device for an internal combustion engine according to the present invention.

FIG. 2 is a diagram showing the relationship between throttle valve opening and load torque when the diameter of the intake passage is 58 mm.

FIG. 3 is a diagram showing the relationship between the throttle valve opening and the load torque when the diameter of the intake passage is 40 mm.

FIG. 4 is a vertical cross-sectional view of a main part of a conventional intake air amount control device for an internal combustion engine.

5 is a system diagram showing a state in which the intake air amount control device of FIG. 4 is incorporated in an internal combustion engine.

[Explanation of symbols]

 1 Throttle body 2 First intake passage 3 Second intake passage 4 Throttle valve shaft 5 First throttle valve 6 Second throttle valve 24 Motor 30 Electronic control unit

Claims (1)

[Claims] 1. An intake passage passing through a throttle body is
Opening and closing is controlled by a throttle valve attached to a throttle valve shaft that is rotatably supported by the throttle body, and the throttle valve shaft is given a rotational force according to an electric signal output from an electronic control unit. In an intake air amount control device for an internal combustion engine in which a motor for activating a throttle valve shaft is provided, a first intake passage 2 and a second intake passage 3 are bored through a throttle body 1 And a single throttle valve shaft 4 that traverses the inside of the first intake passage 2 and the second intake passage 3 is rotatably supported and arranged, and the first intake passage 2 is opened and closed on the throttle valve shaft 4. First throttle valve 5
And a second throttle valve 6 for opening and closing the second intake passage 3 is attached, and rotation of the motor 24 is applied to the throttle valve shaft 4, and an intake air amount control device for an internal combustion engine.