WO2009106712A1

WO2009106712A1 - Valve for a combustion engine air intake system

Info

Publication number: WO2009106712A1
Application number: PCT/FR2008/001752
Authority: WO
Inventors: Samuel Leroux; Guillaume Davoult
Original assignee: Valeo Systemes De Controle Moteur
Priority date: 2007-12-19
Filing date: 2008-12-16
Publication date: 2009-09-03
Also published as: FR2925610A1; FR2925610B1

Abstract

The invention relates to a valve (14) for a combustion engine air intake system. The valve comprises three ducts (24, 27, 29) corresponding to one inlet (24), a first outlet (27) and a second outlet (29), and two butterflies (32, 33) for adjusting the proportion of air to be directed towards the first and second outlets (27, 29). The inlet (24) is intended to be connected to a line (26) such as a line connected to an air compressor of this engine, the first outlet (27) is intended to be connected to an inlet manifold via a heat exchanger, and the second outlet (29) is intended to be connected directly to the air manifold of the engine. The ducts of the first and second outlets (27, 29) are directed with respect to the inlet duct (24) at different angles (α₁₂, α₁₃). The invention applies in particular to a power plant of the supercharged type.

Description

Valve for heat engine air intake system

The invention relates to a valve intended to equip a supercharged engine and / or recirculation of exhaust gas.

BACKGROUND OF THE INVENTION

FIG. 1 diagrammatically shows a power unit marked 1, comprising a heat engine 2 supercharged by a turbocharger 3. The turbocharger comprises a turbine 4 connected to an outlet manifold 5 of this engine via an exit line 6, and a compressor 7 mounted on a shaft 8 common with the turbine to be rotated by it. The compressor 7 compresses outside air which is then admitted into an inlet manifold 9 of the engine 2.

A radiator 11 for cooling the charge air and a bypass 12 are interposed between the compressor 7 and the inlet manifold 9, so as to cool or not to cool the supercharging air delivered by the compressor before admission. in the engine. The compressor 7 is thus connected to an inlet 13 of a three-way distribution valve 14, by a compressed air line 16, this valve 14 having a first outlet 17 connected to the radiator 11 by a first line 18, and a second output 19 connected to the branch 12. The branch 12 and the outlet of the radiator 11 meet in an air intake line 21 opening into the manifold 9.

The valve 14 which is schematically shown in section in FIG. 2 comprises two butterflies 22 and 23 situated respectively in the first and in the second outlet, which are controlled to distribute the air between the radiator 11 and the bypass 12, in order to obtain a desired temperature of the air at the inlet manifold 9. In the case of Figure 2, the first butterfly 21 is fully open while the second butterfly 22 is completely closed, the entire air from the compressor 7 is thus directed to the radiator 11, before being admitted into the collector 9.

FIG. 3 shows the field of the total pressure, expressed in Pascal, of the air circulating in this valve 14, when all the air coming from the compressor 7 is directed towards the radiator 11. As shown in this figure, this valve greatly disturbs the flow of air, introducing high pressure differences between the inlet and the outlet.

Specifically, when the air flow rate is 0.2 kg / s, the pressure drop introduced by the valve, ie the difference between the average inlet pressure and the average outlet pressure is 34 millibar. This corresponds to a pressure drop which penalizes the consumption of the powertrain.

OBJECT OF THE INVENTION The object of the invention is to propose a solution for reducing the consumption of such a vehicle. SUMMARY OF THE INVENTION

For this purpose, the subject of the invention is a device for regulating the temperature of the intake gases of a heat engine, comprising a valve including an inlet pipe as well as a first outlet pipe and a second outlet pipe. , a radiator connected to the first output and a bypass line connected to the second output, the radiator and the bypass line being intended to be connected to an intake manifold of the engine, the inlet of the valve being intended to receive the gases to be regulated, the valve comprising two butterflies for regulating the temperature by adjusting the proportion of gas to be directed towards the radiator and the bypass, characterized in that the pipes of the first and the second outlet of the valve have different inclinations with respect to the inlet pipe of the valve.

With this solution, the most used pipe over the entire life of the engine can be oriented to have the lowest inclination. The pressure drop that it introduces is thus reduced, which has the effect of reducing the consumption of the vehicle.

The invention also relates to a device as defined above, wherein the inclination of the first output with respect to the input is lower than the inclination of the second output relative to the input.

The invention also relates to a device as defined above, wherein the first output is aligned with the input. The invention also relates to a device as defined above, wherein the inclination of the second output relative to the input is between zero and ninety degrees.

The invention also relates to a device as defined above, wherein the first and the second output are inclined relative to each other by an angle greater than one hundred degrees.

The invention also relates to a three-way valve as defined above. The invention also relates to a heat engine equipped with a control device as defined above.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a schematic view of a heat engine air intake system;

Figure 2 is a schematic representation of a valve of the state of the art;

Figure 3 is a diagram representative of the pressure drop in the valve of the type of that of Figure 2; Figure 4 is a schematic representation of the valve according to the invention;

Figure 5 is a diagram representative of the pressure drop in the valve according to the invention. DETAILED DESCRIPTION OF THE INVENTION

The idea underlying the invention lies in the finding that in most life situations of the engine group, the air from the compressor must be cooled before being introduced into the engine. The valve according to the invention is asymmetrical: it introduces a small pressure drop when it directs the air towards the radiator and a higher pressure drop when directing the air directly towards the collector.

The overall efficiency of the powertrain is then optimized because the pressure drop introduced by the valve is low in the majority of engine life situations, and this pressure drop is greater only in occasional situations.

It is essentially in the transient conditions, especially during a short time after start that the air from the turbocharger must be admitted directly into the engine, without cooling.

The valve of the device according to the invention which is schematically shown in FIG. 4, where it is marked by 23, thus has an asymmetrical morphology. It comprises an inlet pipe 24 intended to be connected to a line 26 for supplying air or gas whose temperature must be regulated, a first outlet 27 intended to be connected to a supply line 28 of a radiator cooling, and a second output 29 intended to be connected to a bypass line 31 directly connected to an intake manifold of the engine. It is thus integrated into a thermal engine air intake system of the same type as that of FIG.

It also has a first and a second butterfly marked 32 and 33 are located respectively at the first output and the second output. They are controlled and moved together by a mechanical drive system not shown, to distribute the air to be admitted in the radiator and in the collector, so as to obtain in this collector a temperature corresponding to a desired value.

The input 24 extends along an axis marked by AX1, the first output 27 extends along another axis marked by AX2, and the second output 28 extends along a third axis indicated by AX3.

In the ideal case, corresponding to that of FIG. 4, the pipe section of the first outlet 27 and the pipe section of the inlet 24 are aligned, which means that they are spaced at an angle a ₁₂ equal to one hundred and eighty degrees. On the other hand, the second output 29 and the pipe section of the inlet 24 are oriented at right angles, the angle αi ₃ separating them thus being ninety degrees.

In other words, the smallest angle between the AXL axes AX2 and which corresponds to the inclination iχ ₂ of the first outlet 27 with respect to the input 24 is zero, and the smallest angle between the axis AXL and AX3 which corresponds to the inclination of the second outlet 29 with respect to the inlet 24 is ninety degrees. As can be seen in the figures, we have ₁₂ + α _i2 = ii ₃ + (Xi ₃ = 180 °.

The pressure drop introduced is then minimal when the air is completely directed towards the radiator, that is to say when the powertrain is operating in steady state which corresponds to the largest part of its operating time when considering the whole life of a powertrain.

Other angular arrangements different from those of FIG. 4 can also be retained as soon as they introduce a minimal pressure drop in the operating situations of the engine which correspond to the greater part of its operating time.

In the example of FIG. 5, the angle αi ₂ separating the first outlet 27 with respect to the inlet 24 is one hundred and forty-seven and a half degrees, so that the inclination ii2 of the first outlet 27 relative to the entrance 24 is thirty-two and a half degrees. On the other hand, the angle between the second outlet 29 of the inlet 24 is about ninety-five degrees, the inclination i- ₃ of the second outlet

29 with respect to the inlet 24 being then eighty-five degrees.

This last arrangement illustrated in FIG. 5 makes it possible to respond to an integration constraint in which the first outlet 27 can not be completely aligned with the inlet 24, while minimizing the pressure drop introduced by the valve 14 under normal conditions. operation of the engine, ie when all the air from the compressor has to be reheated. As shown in FIG. 5, according to this arrangement, the maximum difference in air pressure, expressed in Pascals in FIG. 5, between two points of the valve is much smaller than in the case of the valve of the valve. State of the art shown in FIG. 3. When the air flow rate is 0.2 kg / s, the pressure drop between the inlet and the outlet of the valve, ie the difference between the mean pressure in and out is then about 16 mbar.

In the examples given above, the valve is integrated in a powertrain comprising an engine supercharged thermal. But the valve according to the invention can also be used in other architectures, for example in cases where the powertrain comprises an exhaust gas recirculation circuit, ie a circuit in which a part of the gases of exhaust is removed for re-injection into the engine manifold.

Claims

An intake gas temperature control device of a heat engine, comprising a valve (14) including an inlet pipe (24) and a first outlet pipe (27) and a second outlet pipe (29), a radiator connected to the first output (27) and a bypass line (31) connected to the second output

(29), the radiator and the bypass line (31) being intended to be connected to an intake manifold of the engine, the inlet (24) of the valve being intended to receive the gases to be regulated, the valve (14) ) including two butterflies

(32, 33) for controlling the temperature by adjusting the amount of gas to be directed to the radiator and the bypass, characterized in that the lines of the first and second outlets (27, 29) of the valve (14) have different inclinations (ii ₂ , ii ₃ ) with respect to the inlet line (24) of the valve (14).

2. Device according to claim 1, wherein the inclination (ii2) of the first outlet (27) with respect to the inlet (24) is smaller than the inclination (ii ₃ ) of the second outlet (29). with respect to the inlet (24).

3. Device according to claim 1 or 2, wherein the first output (27) is aligned with the input (24).

4. Device according to one of claims 1 to 3, wherein the inclination (ii ₃ ) of the second outlet (29) relative to the inlet (24) is between zero and ninety degrees.

5. Device according to one of claims 1 to 3, wherein the first and the second outlet (27, 29) are inclined relative to each other by an angle (ii2 + ii3) greater than one hundred degrees .

6. Heat engine equipped with a regulating device according to one of claims 1 to 5.