KR20040021937A - Exhaust gas recirculation apparatus of turbo charger - Google Patents

Abstract

PURPOSE: An exhaust gas recirculation apparatus of a turbo charger is provided to simplify components of a turbo charger and improve the durability of the turbo charger. CONSTITUTION: An exhaust gas recirculation port(30) is formed in ring shape on one side of a throat(27) installed in a compressor(23) of a turbo charger(20) to induce part of exhaust gas. A ring-shaped slot(31) is outward inclined to flow air flowing in the exhaust gas recirculation port to a front of a diffuser(28) of the throat. An exhaust gas recirculation line(33) connects one side of the exhaust gas recirculation port with one side of an exhaust manifold(32) for inducing part of the exhaust gas to the exhaust gas recirculation port. An adjusting valve(34) is formed in the middle of the exhaust gas recirculation line to control a quantity of recirculated exhaust gas. An electronic control unit(35) controls the adjusting valve.

Description

Exhaust gas recirculation apparatus of turbo charger

The present invention relates to an exhaust gas recirculation structure and a control method of a turbocharger. The conventional variable turbocharger is realized by realizing exhaust gas recirculation while allowing a part of the exhaust gas passing through the exhaust manifold to flow into the compressor side of the turbocharger. The present invention relates to a turbocharger exhaust gas recirculation structure for simplifying turbocharger components and improving durability.

In general, a diesel engine using diesel fuel has a turbocharger configured to pressurize intake air by using exhaust pressure of exhaust gas and to supply pressurized intake air to the combustion chamber.

FIG. 2 schematically shows a general intake air supply system of a diesel engine. Intake air supplied to the engine 11 flows into the air duct 12 and is purified by the air cleaner 13 and then discharged. It is pressurized by the turbocharger 14 which is rotated by pressure. However, since the temperature control of the suction air pressurized by the turbocharger 14 is artificially impossible, the temperature of the suction air is excessively increased more than necessary. Therefore, excessively elevated state of the intake air lowers the density of the intake air, which does not improve the output of the engine. Thus, to improve this, an intercooler 15 for cooling the air pressurized by the turbocharger 14 is formed in the middle of the intake line connecting the turbocharger 14 and the intake manifold.

In addition, the intake air cooled by the intercooler 15 is introduced into the combustion chamber while causing a swirl in the surge tank 16 according to the opening amount of the spool valve by the driver's accelerator pedal.

Meanwhile, in a general diesel engine, an exhaust gas recirculation device, which is a device for recycling a part of the exhaust gas discharged to the exhaust system to the intake system, is applied to suppress the generation of nitrogen oxides (Nox). Therefore, a part of the hot exhaust gas discharged from the exhaust manifold is led to the intake manifold, thereby improving the combustion efficiency of the engine. That is, the exhaust pressure to the intake system for the exhaust gas recirculation must be higher than the intake pressure to mix the air, and the combustion efficiency is increased.

By the way, in the high horsepower high-power engine, when the intake air amount increases, there is a region in which the boost pressure is higher than the exhaust pressure, and in this region, the exhaust gas is not recycled. On the other hand, if the supercharge pressure is lowered to reduce the above phenomenon, the engine output decreases and the fuel economy performance is disadvantageous.

Therefore, in order to solve the above problem, some conventional engines form a flue gas passage in the turbocharger so that exhaust gas recirculation is performed while the back pressure of the exhaust gas is increased. The type of engine applied in this way is generally referred to as a variable geometry turbocharger (VGT).

However, the apparatus to which the variable turbocharger is applied has a number of components constituting the turbocharger, which adversely affects the layout of the engine and is disadvantageous in terms of durability and reliability of the engine. In addition, in order to adjust the boost pressure and the exhaust pressure, there was a problem in that a large number of test data must be obtained in the engine development process.

Accordingly, the present invention has been made to solve the above problems, by applying a conventional variable turbocharger by realizing the exhaust gas recirculation by allowing a part of the exhaust gas passing through the exhaust manifold to the compressor side of the turbocharger. It is an object of the present invention to provide a turbocharger exhaust gas recirculation structure in order to make the turbocharger components simpler and improve durability.

The present invention as a means for providing the above object,

A turbocharger for pressurizing intake air is mounted on one side of the exhaust manifold, and in the exhaust gas recirculation structure for guiding a part of the exhaust gas into the intake machine,

An exhaust gas recirculation port formed in an annular shape on one side of the throat provided in the compressor of the turbocharger;

An annular slot formed to be inclined outward so that air flowing through the exhaust gas recirculation port flows toward the diffuser front side of the throat;

An exhaust gas recirculation line for connecting one side of the exhaust gas recirculation port and one side of the exhaust manifold to direct a part of the exhaust gas to the exhaust gas recirculation port;

A control valve formed in the middle of the exhaust gas recirculation line to adjust the gas amount of the exhaust gas to be recycled;

An electronic controller for controlling the regulating valve; Characterized in that comprises a.

1 is a configuration of the exhaust gas recirculation structure of the turbocharger according to the present invention.

2 is a view for explaining a conventional technology.

※ Explanation of code for main part of drawing

20: turbocharger 21: main housing

22: rotating shaft 23: compressor

24 turbine 25 compressor housing

26 turbine housing 27 throat

28: diffuser 30: exhaust gas recirculation port

31: slot 32: exhaust manifold

33 exhaust gas recirculation line 34 control valve

35: electronic control device

Hereinafter, a preferred embodiment according to the exhaust gas recirculation structure and operation formed by the present invention will be described in detail with the accompanying drawings.

1 is a configuration diagram of an exhaust gas recirculation structure of a turbocharger formed by the present invention, and reference numeral 20 shown in the drawing indicates a turbocharger formed by the present invention.

The turbocharger 20 is provided with a compressor 23 and a turbine 24 on one side of the main housing 21, similarly to a conventional turbocharger, and has a compressor 23 and a turbine at the center of the main housing 21. The rotating shaft 22 which connects 24 coaxially is formed. The compressor 23 and the turbine 24 surround the compressor 23 and the turbine 24, respectively, and the compressor housing 25 and the turbine housing 26 for guiding the flow paths of the intake air and the exhaust gas, respectively. ) Is formed. The pressurized air passage 25a and the exhaust gas passage 26a provided in the compressor housing 25 and the turbine housing 26 are formed in an annular shape.

In particular, a throat 27 is formed inside the compressor housing 25 so that suction air pressurized by the compressor 23 can be led to the pressurized air passage 26a. An end portion of the throat 27 connected to the passage 25a will be referred to as a diffuser 28 for convenience of description.

On the other hand, one side of the main housing 21 formed by the present invention, that is, the side connected to the compressor 23, the exhaust gas recirculation port for allowing a part of the exhaust gas to be guided to the throat 27 side ( 30) is formed in an annular shape. In addition, a slot 31 is formed to allow the air flowing in the exhaust gas recirculation port 30 to be led to the pressurized air passage 25a through the diffuser 28, and the slot 31 is exhaust gas recirculation. It is formed by an inclined hole that gradually extends toward the diffuser 28 from the port 30 side. In particular, the exhaust gas recirculation port 30 and the slot 31 is preferably molded by a weight loss method in the process of molding the main housing 21.

In addition, an exhaust gas recirculation line 33 connecting one side of the exhaust gas recirculation port 30 and one side of the exhaust manifold 32 is formed, and the exhaust gas recirculation line 33 receives a portion of the exhaust gas. To lead to the recirculation port 30.

In addition, an adjustment valve 34 for adjusting the amount of exhaust gas flowing from the exhaust manifold 32 to the compressor 23 through the exhaust gas recirculation line 33 is formed in the middle of the exhaust gas recirculation line 33. The adjustment valve 34 is configured to be adjusted by the electronic control device 35 according to the operating environment of the engine, such as the engine speed and the engine load.

The structure of this invention formed as mentioned above is demonstrated.

When the engine to which the exhaust gas recirculation structure of the turbocharger according to the present invention is applied starts, the electronic controller 35 checks all operating conditions of the engine such as engine speed, engine load, cooling water temperature, and the like.

Therefore, the electronic control device 35 controls the control valve 34 so that the exhaust gas of a predetermined amount can be recycled in the engine design process.

Thus, when the regulating valve 34 is opened, a part of the exhaust gas flowing to the exhaust manifold 32 is led to the exhaust gas recirculation port 30, and the recirculated exhaust gas introduced to the exhaust gas recirculation port 30 is thus introduced. Gas is supplied to the diffuser 28 through the slot 31 while rotating the annular port.

In particular, due to the intake and back pressure of the high-power diesel engine, the intake pressure is larger than the exhaust pressure at a predetermined rotation speed of the engine, so that the exhaust gas can not be recycled in a conventional conventional turbocharger. The exhaust gas is recycled to the throat 27 and the pressure riser of the diffuser 28.

Therefore, when the exhaust gas recirculation apparatus is realized by the apparatus according to the present invention, the structure which was complicated for exhaust gas recirculation in the prior art is deleted, thereby reducing the development cost of the engine and reducing the schedule of the engine development. do.

The present invention constituted as described above is an exhaust gas recirculation apparatus for suppressing the generation of nitrogen oxides and improving the combustion efficiency by inducing some of the exhaust gas discharged to the exhaust manifold side to the intake machine, the compressor on one side of the turbocharger There is a great advantage that the exhaust gas recirculation can be made in the taobao charger by allowing the recycle gas induced in the exhaust system to be guided to the throat and diffuser provided. In addition, since the exhaust gas recirculation structure is installed in the turbocharger, many structures which are complicated for exhaust gas recirculation in the related art are deleted.

Claims (2)

A turbocharger for pressurizing intake air is mounted on one side of the exhaust manifold, and in the exhaust gas recirculation structure for guiding a part of the exhaust gas into the intake machine, An exhaust gas recirculation port 30 formed in an annular shape on one side of the throat 27 provided in the compressor 23 of the turbocharger; An annular slot (31) formed to be inclined outward so that air flowing through the exhaust gas recirculation port (30) flows toward the diffuser (28) front side of the throat (27); An exhaust gas recirculation line 33 connecting one side of the exhaust gas recirculation port 30 and one side of the exhaust manifold 32 to direct a part of the exhaust gas to the exhaust gas recirculation port 30; An adjustment valve 34 formed in the middle of the exhaust gas recirculation line 33 to adjust the gas amount of the exhaust gas to be recycled; An electronic controller 35 for controlling the regulating valve 34; Exhaust gas recirculation structure of the turbocharger comprising a. The method of claim 1, Said exhaust gas recirculation port (30) and the slot (31) are integrally molded in the main housing (21) of the turbocharger (20).