JP2001221044A - Connected exhaust pipe for turbo charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent interference of exhaust gas flowing out of a turbin wheel and a by-pass channel with each other, to improve exhaust efficiency and to stabilize supercharging pressure. SOLUTION: Interference of exhaust gas with each other is prevented by providing a straightening vane 16 to separately circulate the exhaust gas in a pipe at a part where the exhaust gas flowing out of a turbine wheel 11 and a by-pass channel 12 joins.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust pipe connected to a turbine housing in a turbocharger mounted on a vehicle or the like, and more particularly, to an interference between a turbine wheel and exhaust gas flowing out of a bypass passage. The present invention relates to a connection exhaust pipe for a turbocharger, which is prevented.

[0002]

2. Description of the Related Art FIG. 6 schematically shows a supercharging system for an automobile engine, in which a turbine housing 2 of a turbocharger 1 is connected to an exhaust manifold 4 of an engine 3 and a compressor housing 5 is connected to the engine 3. Is connected via a surge tank 7.

An exhaust pipe 8 is connected to a discharge port of exhaust gas in the turbine housing 2, and an intake duct 9 for introducing outside air through an air cleaner (not shown) is connected to an intake port of the compressor housing 5. I have.

[0004] Such a supercharging system is provided with a waste gate valve 10 for controlling the amount of air supplied to the engine, that is, the supercharging pressure to a target value. That is, a bypass passage 12 is formed in the turbine housing 2 to allow a part of the exhaust gas before being introduced into the turbine wheel 11 to escape to the exhaust pipe 8, and a waste gate valve 10 is provided at an inlet portion thereof. By opening and closing by a diaphragm type actuator 13 connected to the intake pipe 6, the rotation of a compressor wheel 14 coaxial with the turbine wheel 11 is controlled, and the supercharging pressure is optimally controlled.

[0005]

As described above, in the apparatus adopting the waste gate system in which a part of the exhaust gas is released to the exhaust pipe 8 which is the main flow path via the bypass flow path 12, The exhaust gas passing through the turbine wheel 11 and the exhaust gas flowing out of the bypass flow path 12 interfere at a junction in the exhaust pipe 8, and the flow of the exhaust gas is disturbed. Efficiency decreases.

In this case, especially during high-speed and high-load operation, the back pressure increases, the pumping loss increases, and the engine performance such as output decreases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and it is possible to prevent the exhaust gas flowing out of a turbine wheel from interfering with the exhaust gas flowing out of a bypass passage, thereby improving the exhaust efficiency. It is an object of the present invention to provide a connection exhaust pipe for a turbocharger capable of increasing the pressure, stabilizing the supercharging pressure, and improving the engine performance.

[0008]

In order to achieve the above object, a connecting exhaust pipe for a turbocharger according to the present invention comprises: an exhaust gas passing through a turbine wheel of a turbocharger;
In a turbocharger connection exhaust pipe that merges and discharges exhaust gas flowing out of a bypass flow path bypassing the turbine wheel, in a pipe of a portion where exhaust gas flowing out of the turbine wheel and the bypass flow path merges,
It is characterized in that a flow straightening plate for separately circulating the exhaust gas is provided. According to the present invention having the above-described structure, the respective exhaust gases flowing out of the turbine wheel and the bypass flow path are rectified by the rectifying plates provided in the pipes at the junction thereof and flow separately downstream, so that the exhaust gases interfere with each other. As a result, there is no possibility that the flow will be disturbed, and the exhaust efficiency will be increased, and the supercharging pressure will be stabilized.

In the connection exhaust pipe, a bypass flow path is formed in the turbine housing, and an exhaust gas discharge port from the turbine wheel and an exhaust gas discharge port from the bypass flow path open in the same direction. In things
A joint pipe having a cross-sectional area large enough to cover the exhaust gas discharge ports is connected to a turbine housing,
It is preferable to provide a flow straightening plate for separately flowing exhaust gas from each exhaust gas discharge port in the joint pipe. With this configuration, the exhaust gas immediately after flowing out of the turbine wheel and the bypass flow path immediately flows separately into the two flow paths defined by the rectifying plates in the joint pipe. In addition, since the exhaust resistance is reduced, the exhaust efficiency is further increased, and the supercharging pressure is more stabilized.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. The same members as those shown in FIG. 6 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As schematically shown in FIG. 1, a short joint pipe 15 forming a part of an exhaust pipe is provided at an exhaust gas discharge port of a turbine housing 2 of a turbocharger 1 in a supercharging system similar to FIG. The exhaust pipe 8 is connected via the.

In the joint pipe 15, the turbine wheel 11
A rectifying plate 16 is provided to introduce the exhaust gas discharged from the exhaust gas and the exhaust gas flowing out from the bypass flow path 12 to the exhaust pipe 8 separately at their junction.

FIGS. 2 to 4 show the details of the connection between the turbocharger 1 and the joint pipe 15. The exhaust gas discharge port 17 on the side surface of the turbine housing 2 has:
As shown in FIG. 3, an exhaust gas outlet 18 from the turbine wheel 11 and an exhaust gas outlet 19 from the bypass passage 12 provided in the turbine housing 2 are opened in the same direction.

The joint pipe 15 is bent at its upper end into an arc shape, and the cross-sectional area of the upper end opening is made large enough to cover both the discharge ports 18 and 19 formed at the discharge port 17 for the exhaust gas. The flange 20 fixed to the opening surface is fixed to the discharge port 17 with a plurality of bolts 21.

The length from the upper end of the current plate 16 provided in the joint pipe 15 is substantially half the length of the joint pipe 15, and two flow paths 22a, 22b
Are formed on the inner surface.

The upper end of the one flow path 22a is close to the exhaust gas discharge port 18 from the turbine wheel 11, and the upper end of the other flow path 22b is close to the exhaust gas discharge port 19 of the bypass flow path 12. (See FIG. 3).

By using the joint pipe 15 of this embodiment in the turbocharger 1 having the waste gate valve 10, the exhaust gas discharged from the discharge ports 18 and 19 of the turbine wheel 11 and the bypass passage 12 is As shown in FIG. 4, the gas immediately flows separately into two flow paths 22a and 22b defined by the flow straightening plate 16, and flows into the downstream exhaust pipe 8 after being rectified.

Therefore, as in the prior art, the two discharge ports 18, 1
Exhaust gas discharged from the fuel cell 9 interferes with each other, and the flow of the exhaust gas is disturbed, so that the exhaust efficiency is reduced, and there is no fear that the supercharging pressure becomes unstable, and the engine performance can be improved.

The present invention is not limited to the above embodiment.

In the above embodiment, the exhaust gas bypass passage 12 is provided in the turbine housing 2 of the turbocharger 1, and the straightening plate 16 provided in the joint pipe 15 allows the turbine wheel 11 to be connected to the bypass passage 12. Although the exhaust gas discharged from each of the discharge ports 18 and 19 is rectified and flows downstream, the present invention can be applied to a case where the bypass flow path is formed separately from the turbocharger 1. it can.

FIG. 5 schematically shows an example in which the exhaust manifold 4 and the exhaust pipe 8 are connected by a bypass pipe 23 having a waste gate valve 10 at an inlet to bypass the turbocharger 1. When the bypass flow path 24 is formed, the flow path of the exhaust pipe 8 and the bypass flow path 24 are formed.
The exhaust gas discharged from the turbine wheel 11 and the exhaust gas discharged from the bypass pipe 23 are separately rectified and flowed downstream.

Even in the case of the one having such a bypass pipe 23, the interference of the exhaust gas is prevented, as described above, so that the exhaust efficiency can be increased and the supercharging pressure can be stabilized.

The joint pipe 15 is omitted, and the exhaust pipe 8 having a flow straightening plate in the upper end pipe is directly connected to the turbine housing 2.
You may make it attach to.

[0024]

According to the present invention, the following effects can be obtained. (A) According to the first aspect of the invention, the exhaust gas flowing out of the turbine wheel and the bypass flow passage is prevented from interfering with each other, the exhaust efficiency is increased, and the supercharging pressure is stabilized. Engine performance can be improved. (B) According to the second aspect of the present invention, the exhaust gas flowing out of the turbine wheel and the bypass flow path immediately flows separately into the two flow paths defined by the straightening plates in the joint pipe. There is almost no risk of interference between them, and the exhaust efficiency of the turbocharger having the bypass flow passage can be greatly increased, and the supercharging pressure can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a supercharging system of an engine to which the present invention is applied.

FIG. 2 is a front view showing details of a connection portion between a turbocharger and a joint pipe.

FIG. 3 is an enlarged vertical sectional side view taken along the line III-III of FIG. 2;

FIG. 4 is an enlarged vertical sectional side view taken along line IV-IV of FIG.

FIG. 5 is a schematic diagram of a supercharging system to which another embodiment of the present invention is applied.

FIG. 6 is a schematic view of a supercharging system including a conventional exhaust pipe.

[Explanation of symbols]

 1 Turbocharger 2 Turbine housing 3 Engine 4 Exhaust manifold 5 Compressor housing 6 Intake pipe 7 Surge tank 8 Exhaust pipe 9 Intake duct 10 Wastegate valve 11 Turbine wheel 12 Bypass flow path 13 Actuator 14 Compressor sub wheel 15 Coupling pipe 16 Rectifying plate 17 Discharge port 18, 19 Exhaust gas discharge port 20 Flange 21 Bolt 22a, 22b Flow path 23 Bypass pipe 24 Bypass flow path 25 Rectifier plate

Claims (2)

[Claims] 1. A turbocharger connecting exhaust pipe for merging and discharging exhaust gas passing through a turbine wheel of a turbocharger and exhaust gas flowing out of a bypass flow path bypassing the turbine wheel. A connection exhaust pipe for a turbocharger, wherein a straightening plate for separately flowing the exhaust gases is provided in a pipe at a portion where the exhaust gases flowing out from a bypass flow path join. 2. A method according to claim 1, wherein a bypass flow passage is formed in the turbine housing, and an exhaust gas discharge port from the turbine wheel and an exhaust gas discharge port from the bypass flow passage open in the same direction. A joint pipe having a cross-sectional area large enough to cover both exhaust gas discharge ports was connected to the turbine housing, and a straightening plate for separately flowing exhaust gas from each exhaust gas discharge port was provided in the joint pipe. A connection exhaust pipe for a turbocharger according to claim 1.