JP2833346B2 - Intake control device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake control device provided in, for example, an internal combustion engine for an automobile, and more particularly, to an intake control device for converting a part of the energy of intake air into electric energy and recovering it. The present invention relates to an intake control device.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 2-291426 discloses an "intake control device for an internal combustion engine" for the purpose of reducing pumping loss and improving fuel efficiency when the engine load is low.

In this technique, as shown in FIG. 2, an intake passage (primary intake passage) is provided in a combustion chamber 32 of an engine 31.
33 are connected. In the middle of the intake passage 33, a turbine 34 (air motor) that rotates by the flow of intake air is provided. The turbine 34 is connected to a crankshaft 40 via a belt 39 and the like. The intake passage 33 is provided with a bypass passage 35 (secondary intake passage) that connects the upstream side and the downstream side of the turbine 34. In the intake passage 33 and the bypass passage 35, throttle valves 37 and 38 which are opened and closed in conjunction with operation of an accelerator pedal 36 are provided, respectively.

[0004] When the engine 31 is under a low load, the throttle valve 38 of the bypass passage 35 is completely closed, and the throttle valve 37 of the intake passage 33 is slightly opened. Then, all the intake air is guided to the turbine 34 through the intake passage 33, passes through the turbine 34, and reaches the combustion chamber 32. The passage of the intake air rotates the turbine 34, and a part of the energy (intake energy) of the intake air is recovered. The rotation of the turbine 34 is transmitted to the crankshaft 40 via the belt 39 and the like.

[0005] Accordingly, when the engine 31 is under a low load, a pumping loss occurs, but this loss is compensated by the recovery of the intake air energy. Along with this, fuel efficiency at the time of low load is improved.

[0006]

However, in the above prior art, the adjustment of the amount of intake air to the combustion chamber 32 is substantially performed by adjusting the opening degrees of the throttle valves 37 and 38. Therefore, when the depression amount of the accelerator pedal 36 is small and the throttle valve 37 is almost fully closed, much of the intake energy is consumed by the throttle valve 37. As a result, effective recovery of intake energy over a wide engine load range could not be expected.

The present invention has been made in view of the above circumstances, and has as its object to provide an intake control device for an internal combustion engine that can effectively recover intake energy over a wide load range of the internal combustion engine. Is to do.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is provided in the middle of an intake passage of an internal combustion engine,
An impeller that rotates by the flow of the intake air to adjust the flow rate, and is connected to an output shaft of the impeller to generate electric power based on the rotation of the impeller and to generate the electric power in proportion to the electric power. And a control means for increasing the power generation amount of the generator as the required intake air amount according to the operation state of the internal combustion engine is smaller.

[0009]

According to the above construction, when the impeller is rotated by the energy of the intake air flowing in the intake passage, the generator connected to the output shaft of the impeller operates to generate electric power. During the operation of the generator, a force acts to suppress the rotation of the impeller. This force is proportional to the amount of power generated by the generator.

When the required intake air amount according to the operating state of the internal combustion engine is small, the control means increases the power generation amount of the generator. Then, the force for suppressing the rotation of the impeller by the generator increases. Accordingly, the impeller becomes difficult to rotate, so that the intake air does not easily pass through the impeller, and the amount of intake air reaching the internal combustion engine decreases.

Conversely, if the required intake air amount is large, the control means reduces the amount of power generated by the generator. Then, the force for suppressing the rotation of the impeller by the generator decreases. Along with this, the impeller becomes easy to rotate, the intake air easily passes through the impeller, and the amount of intake air reaching the internal combustion engine increases.

As described above, the impeller, the generator, and the control means not only convert part of the energy of the intake air into electric power and recover it, but also exert a function of adjusting the intake air amount. The adjustment of the intake air amount performs at least a part of the overall intake air amount control in the internal combustion engine. For this reason, the share of the throttle valve in the total intake amount control is reduced.
As a result, a loss of intake energy due to the throttle valve is reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an intake control device for an internal combustion engine according to the present invention will be described below in detail with reference to FIG.

FIG. 1 is a schematic configuration diagram showing an intake control device for an internal combustion engine in this embodiment. An intake pipe 3 as an intake passage is connected to a combustion chamber 2 of an engine 1 as an internal combustion engine, and intake air is introduced into the combustion chamber 2 through the intake pipe 3. An exhaust pipe 4 is connected to the exhaust side of the combustion chamber 2, and exhaust gas generated in the combustion chamber 2 is led out of the engine 1 through the exhaust pipe 4. An air motor (positive displacement pump) 5 is provided in the intake pipe 3. An impeller (not shown) of the air motor 5 is rotated by the flow of the intake air, and the rotation of the impeller causes resistance of the flow of the intake air to adjust the flow rate of the intake air.

The output shaft of the impeller of the air motor 5 includes:
A generator 6 that generates electric power based on the rotation of the impeller is connected. The negative electrode of the generator 6 is grounded, and the positive electrode is connected to the emitter 7E of the transistor 7. The generator 6 has a function of suppressing the rotation of the impeller in addition to the power generation function. The rotation suppressing force of the generator 6 is proportional to the amount of electric power extracted from the generator 6. That is, when the current taken out is small, the rotation suppressing force is small, and when the current is large, the rotation suppressing force is large. When the rotation suppressing force decreases, the impeller easily rotates and the flow rate of intake air increases. When the rotation suppressing force increases, the impeller hardly rotates and the flow rate of intake air decreases.

The base 7B of the transistor 7 as a control means is connected to the output terminal of the potentiometer 8, and the collector 7C is connected to the battery 12 via the diode D. Transistor 7 outputs a take-out current (emitter current I B) from generator 6 based on a control current (base current IB) corresponding to the voltage supplied to base 7B.
E), that is, the power generation amount of the generator 6 is controlled. The transistor 7 supplies the extracted current IE to the battery 12 via the diode D.

The potentiometer 8 comprises a resistor 8a and a slider 8b. One end of the resistor 8a is connected to the constant voltage VB, and the other end is grounded. The slider 8b is connected to the accelerator pedal 9, slides on the resistor 8a in accordance with the amount of depression of the accelerator pedal 9, and supplies a voltage obtained by dividing the constant voltage VB to the base 7B from an output terminal. I do.
In this embodiment, when the depression amount of the accelerator pedal 9 is small, the slider 8b is connected to the ground side of the resistor 8a (the lower side in FIG. 1).
The slider 8b moves toward the constant voltage VB (upward in FIG. 1) as the depression amount of the accelerator pedal 9 increases.

The potentiometer 8 includes an accelerator pedal 9
Is large (the slider 8b moves to the constant voltage VB side), the potential of the base 7B is raised, and conversely, the accelerator pedal 9 is small (the slider 8b moves to the ground side). ), And lower the potential of the base 7B.

A vehicle electric load 13 and an alternator 14 are connected to the battery 12. Therefore, the electric power generated by the generator 6
And the vehicle electric load 13. Note that the diode D is for protecting the transistor 7 from a reverse voltage caused by the battery 12 and the alternator 14.

Next, the operation of the intake control device having the above configuration will be described. First, when the depression amount of the accelerator pedal 9 is small, that is, when the intake amount required by the engine 1 (required intake amount) is small, the slider 8b of the potentiometer 8 moves to the ground side, The potential of the base 7B decreases. The control current IB increases due to the decrease in the potential of the base 7B, and the extraction current IE
And the power generation amount of the generator 6 increases. For this reason, the rotation suppressing force of the generator 6 increases, and the impeller becomes difficult to rotate. As a result, the intake air does not easily pass through the impeller, and the amount of intake air flowing into the combustion chamber 2 decreases.

Conversely, when the depression amount of the accelerator pedal 9 is large, that is, when the required intake air amount is large, the slider 8b of the potentiometer 8 moves to the constant voltage VB side and the transistor 7 The potential of the base 7B increases. As the potential of the base 7B rises, the control current IB decreases, the takeout current IE decreases, and the power generation of the generator 6 decreases. For this reason, the rotation suppressing force of the generator 6 decreases, and the impeller easily rotates. As a result, the intake air easily passes through the impeller, and the amount of intake air flowing into the combustion chamber 2 increases.

As described above, in this embodiment, part of the intake energy is converted into rotational energy by the impeller of the air motor 5. Then, the rotational energy is converted into electric energy by the generator 6 and the battery 12
And the vehicle electric load 13. Therefore, the intake energy can be collected and used as electric energy.

In this embodiment, the slider 8b is slid according to the depression amount of the accelerator pedal 9, and the control current I
By changing B, the extraction current IE is controlled. Then, by controlling the extraction current IE, the amount of power generated by the generator 6 is changed to adjust the amount of intake air to the combustion chamber 2. Therefore, the intake air amount can be adjusted simultaneously with the recovery of a part of the intake energy. Therefore, it is possible to control the intake air amount without using a conventional throttle valve. As a result, there is no loss of intake energy due to the throttle valve in the conventional engine low load range, and the intake energy can be effectively recovered over a wide range.

Further, in this embodiment, part of the intake energy is converted into electric energy and collected, so that under the condition of the same intake pressure and the same intake amount, the intake energy is changed according to the energy recovery. Decrease. Due to this decrease, the temperature of the intake air downstream of the air motor 5 decreases, and the amount of nitrogen oxides generated during combustion decreases.

In particular, when the temperature of the intake air decreases when the engine 1 is partially loaded, the wall surface of the intake pipe 3 is also cooled. Therefore, even during a transition from this state to when the engine 1 is brought into a full load state, a rise in the intake air temperature is suppressed by the wall surface of the intake pipe 3. As a result, volumetric efficiency is increased, and acceleration performance is improved.

In addition, in this embodiment, as the intake air temperature decreases, the ignition timing region restricted by knocking can be narrowed. Therefore, the engine efficiency can be increased as a whole. In addition, since the temperature at the compression top dead center in the combustion chamber 2 can be reduced, knocking can be suppressed.

It should be noted that the present invention is not limited to the above-described embodiment, but may be carried out as follows by appropriately changing a part of the configuration without departing from the spirit of the invention. (1) In addition to the configuration of the above-described embodiment, a throttle valve similar to the related art may be provided upstream of the air motor 5. In this case, the adjustment of the intake air amount by the air motor 5 or the like plays at least a part of the overall intake air amount control in the engine 1. For this reason, the burden on the throttle valve conventionally used for controlling the intake air amount is reduced. As a result, the loss of intake energy due to the throttle valve is reduced, and the intake energy can be effectively recovered over a wide load range.

(2) In the above embodiment, the accelerator pedal 9
Slider 8b of potentiometer 8 according to the amount of depression
Is slid to change the control current IB,
Instead, an accelerator sensor for detecting the opening of the accelerator pedal 9 may be provided, and the control current IB may be changed by the controller based on the detection result of the accelerator sensor.

(3) In the above embodiment, a positive displacement pump is used as the air motor 5, but a non-positive displacement pump may be used.

[0030]

As described in detail above, according to the intake control system for an internal combustion engine of the present invention, the smaller the required intake air amount in accordance with the operating state of the internal combustion engine, the larger the power generation amount of the generator. Therefore, it is possible to adjust the intake air amount at the same time as the intake energy is recovered, and it is possible to reduce the intake energy loss especially at low load and to effectively collect the intake energy over a wide engine load range. It has excellent effects.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an intake control device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing an intake control device for an internal combustion engine according to the related art.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine as an internal combustion engine, 3 ... Intake pipe as an intake passage, 6 ... Generator, 7 ... Transistor as control means.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makoto Suzuki 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-2-291426 (JP, A) JP-A-59-20526 (JP, A) JP-A-2-181024 (JP, A) JP-A 62-141637 (JP, U) JP-A 59-41100 (JP, U) (58) Fields investigated (Int. Cl. ⁶⁾ F02B 67/08 F02B 61/00 F02M 35/10

Claims (1)

(57) [Claims] An internal combustion engine is provided in the middle of an intake passage,
An impeller that rotates by the flow of intake air to adjust the flow rate, and is connected to an output shaft of the impeller, and generates electric power based on the rotation of the impeller, and the impeller in proportion to the electric power. An intake control device for an internal combustion engine, comprising: a generator for suppressing the rotation of the internal combustion engine; and control means for increasing the power generation amount of the generator as the required intake air amount according to the operating state of the internal combustion engine is smaller. .