TURBINE HOUSING OF TURBOCHARGER FOR VEHICLE

Abstract

A turbine housing of a turbocharger for a vehicle that may be connected to an exhaust manifold and in which a turbine wheel may be rotated using kinetic energy of exhaust gas therein, may include a turbine wheel accepting portion having a circular hole shape so as to receive the turbine wheel therein, a scroll portion surrounding the turbine wheel accepting portion therein, wherein an exhaust gas passage may be formed along a rotating direction of the turbine wheel through the scroll portion, a partition dividing the exhaust gas passage of the scroll portion into at least two passages, and a slit formed at the partition in a radial direction of the partition.

Description

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2011-0112248 filed in the Korean Intellectual Property Office on Oct. 31, 2011, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a turbine housing of a turbocharger for a vehicle. More particularly, the present invention relates to a turbine housing of a turbocharger for a vehicle that improves durability.

2. Description of Related Art

Generally, engine output per cycle can be increased when pressure of intake air flowing into a cylinder of an engine is increased to higher than atmospheric pressure and an air amount in the cylinder is increased. This is called supercharging. Mechanical supercharging deteriorates thermal efficiency even though crankshaft power is increased since output of a crankshaft is used for compressing the intake air.

In order to solve the problem, the turbocharger has been developed. According to the turbocharger, a compressor fixedly connected with an exhaust turbine feeds air into the cylinder when the exhaust turbine is operated by energy from exhaust gas. Therefore, engine output is improved. The turbocharger is widely used with diesel engines where a knocking problem does not generally occur as opposed to a gasoline engine where knocking occurs if the pressure in the cylinder is excessively increased by supercharging.

In detail, in the turbocharger, a turbine wheel that recovers exhaust energy and a compressor wheel that delivers compressed air to the cylinder are disposed on respective ends of the same shaft, and a housing for leading flow of the exhaust gas and the air covers each wheel. Particularly, the turbine housing is divided into a single scroll type having one exhaust gas passage and a twin scroll type having two exhaust gas passages divided by a partition. The twin scroll type prevents exhaust interference of the engine and efficiently uses a pulse effect of the exhaust, and thus rotation efficiency of the turbine wheel can be improved.

However, a pressure difference between cylinders of the twin scroll becomes larger in comparison with that of the single scroll, and thus a side force due to exhaust pulsation is exerted on the partition. Therefore, a crack in the partition often occurs. In addition, durability of the partition may be weakened by repeated expansion and compression due to an abnormal temperature inversion phenomenon of inner and outer portions of the scroll.

The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing a turbine housing of a turbocharger for a vehicle having advantages of improving durability of a partition of the turbine housing as a twin scroll type.

In an aspect of the present invention, a turbine housing of a turbocharger for a vehicle that is connected to an exhaust manifold and in which a turbine wheel is rotated using kinetic energy of exhaust gas therein, may include a turbine wheel accepting portion having a circular hole shape so as to receive the turbine wheel therein, a scroll portion surrounding the turbine wheel accepting portion therein, wherein an exhaust gas passage is formed along a rotating direction of the turbine wheel through the scroll portion, a partition dividing the exhaust gas passage of the scroll portion into at least two passages, and a slit formed at the partition in a radial direction of the partition.

The partition may include a scroll wall extending from an inner surface of the scroll portion toward a center of the turbine housing, and a scroll tip formed at an end portion of the scroll wall, wherein the scroll tip is thinner than the scroll wall.

The scroll portion may include inner rims extending from an inner surface of the turbine housing and the scroll tip is disposed between the rims to deliver the exhaust gas to the turbine wheel through openings formed between the rims and the scroll tip.

A diameter of the rims is shorter than that of the scroll tip.

At least a portion of the exhaust gas passage of the scroll portion is open toward the turbine wheel so as to deliver the kinetic energy of the exhaust gas to the turbine wheel.

A width of the slit is constant along the radial direction of the partition.

The width of the slit is between approximately 0.2 mm and approximately 0.4 mm.

The methods and apparatuses of the present invention may have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a turbine housing of a turbocharger for a vehicle according to an exemplary embodiment of the present invention.

FIG. 2 is a schematic diagram of a turbocharger according to an exemplary embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a scroll portion according to an exemplary embodiment of the present invention.

FIG. 4 is a perspective view of a partition taken along a line A-A in FIG. 2.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.

FIG. 1 is a perspective view of a turbine housing of a turbocharger for a vehicle according to an exemplary embodiment of the present invention.

As shown in FIG. 1, a turbine housing 10 of a turbocharger for a vehicle according to an exemplary embodiment of the present invention is connected with an exhaust manifold 30, and includes a scroll portion 11 and a turbine wheel accepting portion 15.

The turbine housing 10 is adapted to receive exhaust gas from the exhaust manifold 30. In addition, the turbine housing 10 is adapted to operate a turbine by using kinetic energy of the exhaust gas.

The turbine wheel accepting portion 15 is formed with a circular hole shape penetrating the turbine housing 10.

The scroll portion 11 forms passages to flow the exhaust gas along an exterior circumference of the turbine wheel accepting portion 15.

FIG. 2 is a schematic diagram of a turbocharger according to an exemplary embodiment of the present invention.

As shown in FIG. 2, the scroll portion 11 includes a power delivery hole 17, a partition 14, and a twin scroll 12, and a turbine wheel 16 is disposed at the turbine wheel accepting portion 15.

The power delivery hole 17 is formed along an interior circumference of the scroll portion 11 such that an exhaust gas passage of the scroll portion 11 is opened toward the turbine wheel 16 with a predetermined gap.

The partition 14 is formed to divide the exhaust gas passage of the scroll portion 11 into two passages, and the two passages divided by the partition 14 are called the twin scroll 12. In addition, the partition 14 protrudes from an interior surface of a radial outside portion of the scroll portion 11 to the proximity of the power delivery hole 17, and thus the twin scroll 12 is formed.

When the exhaust gas is delivered from the exhaust manifold 30 to the turbine housing 10, the exhaust gas rotates around the turbine wheel 16 along the twin scroll 12. At this time, power of the exhaust gas is delivered to the turbine wheel 16 through the power delivery hole 17. Thus, the turbine wheel 16 is rotated. Arrows in FIG. 2 represent the flow of the exhaust gas supplied from the exhaust manifold 30.

The torque of the turbine wheel 16 rotated by the above-mentioned operation is delivered to a compressor wheel 20, and the compressed air generated by rotation of the compressor wheel 20 is delivered to a cylinder. An operation of the turbocharger that improves output of an engine by these processes is well-known to a person of ordinary skill in the art such that a detailed description thereof will be omitted.

FIG. 3 is an enlarged cross-sectional view of a scroll portion according to an exemplary embodiment of the present invention.

As shown in FIG. 3, the partition 14 dividing the exhaust gas passage of the scroll portion 11 so as to form the twin scroll 12 includes a scroll wall 14a and a scroll tip 14b.

The scroll wall 14a refers to a part of the partition 14 protruded from the interior surface of the radial outside of the scroll portion 11. In addition, the scroll tip 14b refers to another part of the partition 14 close to the power delivery hole 17. In other words, the scroll tip 14b that is close to the turbine wheel 16 is heated faster than the scroll wall 14a. Further, the scroll tip 14b that is formed thinner than the scroll wall 14a emits heat easily and is cooled quickly. Therefore, the compression and the expansion of the scroll tip 14b can be excessively generated in comparison with the scroll wall 14a.

In an exemplary embodiment of the present invention, the scroll portion 11 includes inner rims 25 extending from an inner surface of the turbine housing 10 and the scroll tip 14b is disposed between the rims 25 to deliver exhaust gas to the turbine wheel 16 through openings formed between the rims 25 and the scroll tip 14b.

Diameter of the rims 25 may be shorter than that of the scroll tip 14b.

FIG. 4 is a perspective view of a partition taken along a line A-A in FIG. 2.

As shown in FIG. 4, the partition 14 viewed along the line A-A in FIG. 2 may have an annular shape and includes a slit 18.

At least one of slits 18 is formed radially at the partition 14 of the annular shape. In addition, each slit 18 is a narrow gap formed from the scroll tip 14b to the scroll wall 14a so as to cut the partition 14. Further, the width of the slit 18 may be about 0.2-0.4 mm, and preferably about 0.3 mm.

Three straight slits 18 cutting the partition 14 are shown in FIG. 4, but the number and shape of the slits 18 are not limited to the exemplary embodiment shown in FIG. 4. The number and shape of the slits 18 can be changed variously by a person of ordinary skill in the art.

As described above, since the slits 18 are formed at the partition 14, durability of the partition 14 that experiences repeated expansion and compression can be improved. In other words, since occurrence of a crack at the partition 14 is prevented, deterioration of the turbocharger can be reduced.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.

Claims

1. A turbine housing of a turbocharger for a vehicle that is connected to an exhaust manifold and in which a turbine wheel is rotated using kinetic energy of exhaust gas therein, the turbine housing comprising:

a turbine wheel accepting portion having a circular hole shape so as to receive the turbine wheel therein;

a scroll portion surrounding the turbine wheel accepting portion therein, wherein an exhaust gas passage is formed along a rotating direction of the turbine wheel through the scroll portion;

a partition dividing the exhaust gas passage of the scroll portion into at least two passages; and

a slit formed at the partition in a radial direction of the partition.

2. The turbine housing of claim 1, wherein the partition includes:

a scroll wall extending from an inner surface of the scroll portion toward a center of the turbine housing; and

a scroll tip formed at an end portion of the scroll wall, wherein the scroll tip is thinner than the scroll wall.

3. The turbine housing of claim 2, wherein the scroll portion includes inner rims extending from an inner surface of the turbine housing and the scroll tip is disposed between the rims to deliver the exhaust gas to the turbine wheel through openings formed between the rims and the scroll tip.

4. The turbine housing of claim 3, wherein a diameter of the rims is shorter than that of the scroll tip.

5. The turbine housing of claim 1, wherein at least a portion of the exhaust gas passage of the scroll portion is open toward the turbine wheel so as to deliver the kinetic energy of the exhaust gas to the turbine wheel.

6. The turbine housing of claim 1, wherein a width of the slit is constant along the radial direction of the partition.

7. The turbine housing of claim 6, wherein the width of the slit is between approximately 0.2 mm and approximately 0.4 mm.