JPH07150962A - Bearing housing of turbocharger - Google Patents

Abstract

PURPOSE:To easily largely form a cooling water passage by forming its bearing housing in a divided structure. CONSTITUTION:The bearing housing of a turbocharger is provided with a shaft 10 for fitting a turbine rotor 16, bearing parts 11, 12 for supporting the shaft 10, a cooling water passage 27 for supplying cooling water, a first bearing housing 13 having an oil passage 28 for supplying oil to the slide part between the shaft 10 and the bearing parts 11, 12 and a second bearing housing 23 having a seal ring 24 inserted through the turbine rotor 16. The first bearing housing 13 and the second bearing housing 23 are connected together by a sealing member 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing housing of a turbocharger, which is used, for example, in a turbocharger for an automobile engine.

[0002]

2. Description of the Related Art As a prior art of a bearing housing for a turbocharger of this type, there is known one disclosed in Japanese Utility Model Laid-Open No. 4-79940. This is a bearing housing, a shaft that is housed in the bearing housing and that fixes the turbine rotor, a bearing that supports the shaft, a cooling water passage that supplies cooling water, and oil that is supplied to the sliding portion of the bearing housing. This is a bearing housing of a turbocharger having an oil passage and a seal ring inserted into a turbine rotor, and the bearing housing is formed as an integral structure.

[0003]

According to the above-mentioned conventional technique, it is very difficult to remove the casting sand from the cooling water passage having a complicated structure after the bearing housing is formed by casting. Further, it is not easy to confirm whether or not this casting sand has been completely removed. To provide an oil passage because the bearing housing is an integral structure,
In order to provide an oil passage for lubricating the bearing portion on the turbine side that supports the shaft, it is easy to form an oil passage by inserting a drilling means such as a drill from the oil supply passage. Can not. Also, the cooling water passage cannot be formed large due to the position of the oil passage.

SUMMARY OF THE INVENTION It is an object of the present invention to form a cooling water passage easily and in a large size by using a split bearing structure.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the measures taken in the invention of claim 1 are a shaft for fixing a turbine rotor, a bearing portion for supporting the shaft, and cooling for supplying cooling water. A first bearing housing including a water passage and an oil passage for supplying oil to a sliding portion between the shaft and the bearing portion, a cooling water passage for supplying cooling water, and a seal ring inserted in the turbine rotor are provided. The second bearing housing is provided, and the first bearing housing and the second bearing housing are fastened by a sealing member.

The means taken in the invention of claim 2 is that it has a partition plate which is inserted into the shaft and fixed to the first bearing housing.

[0007]

According to the above-mentioned means of claim 1, when the bearing housing is of the split type, when the cooling water passage formed by the first bearing housing and the second bearing housing is cast, the cooling water passage Casting is easy because one end is open.

Further, the oil passage for lubricating the bearing portion on the turbine side supporting the shaft can be easily formed from the turbine rotor side, and the cooling water passage can be enlarged. Further, since the structure of the cooling water passage is simple, it is easy to remove sand after casting, and casting sand does not remain. In addition, the second bearing housing uses a conventional material such as cast iron because the temperature rises as the temperature of the turbine housing rises. However, the first bearing housing suppresses the temperature rise due to the cooling water passage and the like as compared with the second bearing housing. Therefore, it is possible to use a light metal that is lightweight and has a high heat dissipation effect. As a result, the weight of the bearing housing can be reduced,
Further, the reliability of the bearing portion can be improved.

According to the second aspect of the present invention, since the partition plate is provided, it is possible to suppress the oil that lubricates the sliding surface between the bearing housing and the bearing portion from flowing out to the turbine rotor side. Can be mixed with the exhaust gas to prevent deterioration of the catalyst device and increase pollution due to the white smoke phenomenon of the exhaust gas.

[0010]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a sectional view of the bearing housing of a turbocharger. The shaft 10 is rotatably supported by a first bearing housing 13 by radial bearings (bearing portions) 11 and 12.
1, the axial movement of one end is restricted by the snap ring 14, and the bearing 12 is fixed by the snap ring 15.
It is regulated by. A turbine rotor 16 is integrally fixed to the right end of the shaft 10 in the figure, and a compressor rotor 17 is integrally fixed to the left end of the shaft in the figure.

A seal plate 18 is fixed to the first bearing housing 13 on the right side of the shaft 10 in the compressor rotor 17 in the figure, and thrust bushes 19 and 20 are fixed to the shaft 10. A seal ring (not shown) is arranged between the left side of the thrust bush 19 in the figure and the inner peripheral surface of the seal plate 18.

The thrust bearing 21 has its inner peripheral portion clamped by the thrust bushes 19 and 20, and its outer peripheral portion clamped by the first bearing housing 13 and the seal plate 18. A seal ring plate 22 is arranged on the seal plate 18.

On the other hand, the second bearing housing 23 is provided with a seal ring 24 for preventing oil from flowing out to the turbine rotor 16.

An oil slinger 25 is provided to the right of the radial bearing 11 inserted into the shaft 10 in the figure to prevent oil leakage.

The first bearing housing 13 and the second bearing housing 23 are a metal gasket (sealing member) 26.
The cooling water passage 27 is integrally formed by the first bearing housing 13 and the second bearing housing 23. Further, the first bearing housing 13 is formed with an oil passage 28 for supplying oil to the sliding surface between the bearings 11 and 12 and the shaft 10.

Next, the operation of this embodiment will be described.

When an engine (not shown) is started, the turbine rotor 16 begins to rotate due to exhaust gas and the shaft 10
Rotates. Further, when the engine is started, oil lubricates the radial bearings 11 and 12 through an oil passage 28 from an oil pump (not shown). The oil that has flowed to the radial bearing 11 is the oil that lubricates the outer circumference of the first bearing housing 13 and the radial bearing 11,
It is divided into the shaft 10 and the oil that lubricates the inner peripheral side of the radial bearing 11. Regarding the oil flowing on the shaft 10 side, the oil flowing to the left in the drawing is
The oil is discharged from 0 to the oil drain hole 29. The oil that flows to the right in the figure includes oil that is dropped downward and oil that flows along the shaft 10. Since the oil flowing along the shaft 10 is sealed by the seal ring 24, it does not flow rightward in the drawing from the seal ring 24, but flows into the oil drain hole 30 below. Further, the oil flowing to the outer peripheral side of the radial bearing 11 has an oil chamber 31 formed by the oil slinger 25 and the first bearing housing 13.
And flows from the oil chamber 31 to the oil drain hole 30 below. As a result, the oil flowing out to the turbine rotor 16 side can be suppressed, and the oil can be prevented from being mixed with the exhaust gas to promote the deterioration of the catalyst device and the pollution due to the white smoke phenomenon of the exhaust gas.

Further, since the bearing housing is of a split type, when the cooling water passage 27 formed by the first bearing housing 13 and the second bearing housing 23 is cast, the side of the cooling water passage 27 is opened. Therefore, casting can be performed easily. Further, the oil passage 28a can be easily formed from the turbine rotor 16 side, and the cooling water passage 27 can be formed without narrowing. Further, since the structure of the cooling water passage 27 can be easily made large, the cooling effect can be improved, and further, the sand removal of the casting sand after casting becomes easy and the casting sand does not remain.

Since the second bearing housing 23 is heated to a high temperature by the exhaust gas that rotates the turbine rotor 16, the second bearing housing 23 is made of a conventional material such as cast iron. In addition, since heat transfer is suppressed in the first bearing housing 13 by the large-sized cooling water passage 27, the temperature rise is lower than that in the second bearing housing 23, and thus a light metal (aluminum or the like) having a high heat dissipation effect is used. can do. Further, due to the high heat radiation effect, the frictional heat of the bearings 11 and 12 is radiated and oil deterioration can be prevented. This makes it possible to reduce the weight of the bearing housing and improve the reliability of the bearing portion.

[0021]

According to the invention of claim 1, when the bearing housing is of a split type, when the cooling water passage formed by the first bearing housing and the second bearing housing is cast, the cooling water passage Casting is easy because one end is open. Further, it is possible to form the oil passage that lubricates the bearing portion on the turbine side that supports the shaft from the turbine rotor side, and the cooling water passage can be made large. Further, since the structure of the cooling water passage is simple, it is easy to remove sand after casting, and casting sand does not remain.
In addition, the second bearing housing uses a conventional material such as cast iron because the temperature rises as the temperature of the turbine housing rises. However, the first bearing housing suppresses the temperature rise due to the cooling water passage and the like as compared with the second bearing housing. Therefore, it is possible to use a light metal that is lightweight and has a high heat dissipation effect. As a result, the weight of the bearing housing can be reduced, and the cooling effect is further improved, so that the reliability of the bearing portion can be improved.

According to the second aspect of the invention, since the partition plate is provided, it is possible to suppress the oil that lubricates the sliding surface between the bearing housing and the bearing portion from flowing out to the turbine rotor side. Can be mixed with the exhaust gas to prevent deterioration of the catalyst device and increase pollution due to the white smoke phenomenon of the exhaust gas.

[Brief description of drawings]

1 is a cross-sectional view of an embodiment according to the present invention.

[Explanation of symbols]

 10 ... Shaft 11, 12 ... Radial bearing (bearing part) 13 ... 1st bearing housing 16 ... Turbine rotor 17 ... Cooling water passage 23 ... 2nd bearing housing 24 ... Seal ring 25 ... Oil slinger (partition plate) 26 ... Metal gasket (sealing member) 28 ... Oil passage

Claims (2)

[Claims] 1. A shaft for fixing a turbine rotor,
A first bearing housing including a bearing portion that supports the shaft, a cooling water passage that supplies cooling water, and an oil passage that supplies oil to a sliding portion between the shaft and the bearing portion; A second bearing housing having a cooling water passage to be supplied and a seal ring inserted into the turbine rotor is provided, and the first bearing housing and the second bearing housing are fastened by a sealing member. Bearing housing of the turbocharger. 2. A bearing housing for a turbocharger according to claim 1, further comprising a partition plate which is inserted through the shaft and fixed to the first bearing housing.