JPS6226328A - Turbine device - Google Patents

Abstract

PURPOSE:To reduce the thermal load for a tongue piece part by forming a cooling passage which communicates to the gas discharge port of a static- pressure gas bearing onto the tongue piece part of a turbine housing and efficiently cooling the tongue piece part by utilizing the gas after the completion of the bearing action of the static-pressure gas bearing. CONSTITUTION:Exhaust flows into a turbine housing 1 from an exhaust inlet part 33, and is speed-increased, introduced by a tongue piece part 35, and revolves a turbine 3. While, air is supplied from a high-pressure air feeding part 23, and after passing through the inside of a bearing 15 through an annular passage 21, the air is sent into a bearing gap 17 and floats up a shaft part 9. Then, the air is discharged at the right and left of the bearing 15 from the bearing gap 17. In this case, the air discharged at the right side is introduced into a space 27 from a gas discharge port 26, and flows into a cooling passage 39 through a cut part 29, and then cools the tongue piece part 35, and then is discharged outside from an exhaust outlet part 37. Therefore, the tongue piece part 35 can be efficiently cooled by utilizing the air after the completion of the bearing action.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a turbine device such as a turbocharger or a gas turbine equipped with a hydrostatic gas bearing.

[Prior Art] Generally, turbochargers and gas turbines used in automobiles etc. have a turbine driven by engine exhaust gas,
It mainly consists of a compressor that is interlocked with the turbine through a shaft and sends compressed air to the engine. A tongue portion for guiding the exhaust air extends along the flow direction of the exhaust gas.

On the other hand, in the hydrostatic gas bearings used in such turbine equipment, high-pressure gas (
By supplying air (usually air) to rotate the shaft while floating inside the bearing, it is effective in preventing wear and seizure of the bearing due to *t* during startup or at low speeds. It is known. (Proceedings of the Japan Society of Mechanical Engineers, Part 3, 33
(Refer to Vol. 255, November 1962 issue [Stability of Hydrostatic Gas Journal Bearings]) (Problems to be Solved by the Invention) However, there are The tongue piece, which is necessary to improve the performance of a turbocharger, has a structure in which both sides are constantly exposed to high-temperature exhaust gas during operation, so it is susceptible to periodic heat loads and has poor heat resistance and durability. There is a problem that the turbine housing is lower than other parts of the turbine housing.Furthermore, if the turbine is made of ceramic, it tends to become brittle due to oxidation or the like.

This invention was made by focusing on such conventional problems, and by cooling the tongue part which is exposed to high temperature exhaust gas with the exhaust air (air) which has finished the bearing action of the static pressure gas bearing, the tongue part is removed. The purpose of the present invention is to provide a turbine device in which the heat load applied to the turbine part is reduced.

[Means for Solving the Problem 1] In order to achieve this object, the present invention provides a cooling passage communicating with the gas discharge port of the hydrostatic gas bearing in the tongue portion of the turbine housing in which the turbine is housed. was used as a means to solve the problem.

[Function] High-pressure gas is supplied to the outer circumference of the shaft that connects the turbine and compressor to generate a bearing action, and the gas that has completed this bearing action flows from the outer circumference of the shaft through the gas outlet to cool the tongue part. After cooling the tongue part through a passageway, it is discharged to the outside.

[Example] Hereinafter, the present invention will be described in detail based on the drawings.

FIG. 1 is a sectional view showing a turbocharger to which the present invention is applied, and the structure will be explained first using this drawing. A turbine 3 housed in a turbine housing 1 and a compressor 7 housed in a compressor housing 5 are interlocked and connected by a shaft portion 9. The shaft portion 9 is rotatably supported by a bearing 15 made of porous material, for example, a sintered alloy, and housed in a bearing housing 11 interposed between the turbine housing 1 and the compressor housing 5 via a case 13. A minute bearing gap 17 is formed between the bearing 15 and the shaft portion 9.

An annular W419 is formed on the outer periphery of the bearing 15, thereby forming an annular passage 21 between the bearing 15 and the case 13. A high-pressure air supply port 23 is open. That is, the air supplied to the annular passage 21 from the air supply port 23 passes through the bearing 15 and is sent to the bearing gap ll117 on the outer circumference of the shaft portion 9.

A heat insulator 25 is disposed between the turbine 3 and the bearing 15 side to block the gap between these two members so that the exhaust gas that drives the turbine 3 does not blow into the bearing 15 side. A space 27 that communicates with the gas exhaust port 26 of the bearing gap 17 is formed on the 15 side.

The outer peripheral side of the heat insulator 25 is attached to the inner wall of the turbine housing 1, and a space 27 is formed at the left end in the figure.
A notch 29 is provided that communicates with the. Furthermore, a labyrinth seal 31 is formed at the inner peripheral end of the heat insulator 25 .

FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. It has been extended along with it.

A plurality of cooling passages 39 are bored in the left-right direction in FIG. 1, each communicating with the exhaust outlet portion 37 of the turbine housing 1.

Next, the operation of the turbocharger, which is constructed in this way, will be explained. Exhaust gas flowing into the turbine housing 1 from the exhaust inlet portion 33 is guided by the tongue portion 35, is accelerated, flows through the spiral passage, and rotates the turbine 3. At this time, the exhaust temperature may rise to a maximum of about 1000''C, and in particular, both the outer and inner peripheral surfaces of the tongue portion 35 are exposed to this high-temperature exhaust gas, so the tongue portion 35 receives the exhaust heat the most in the turbine housing 1. Easy to accept.

On the other hand, air supplied from the high-pressure air supply section 23 passes through the annular passage 21 and inside the bearing 15, and then is sent to the bearing gap 17, causing the shaft portion 9 to float. The air that has lifted the shaft portion 9 and finished its bearing action is discharged from the bearing gap 17 to the left and right sides of the bearing 15. The air discharged to the right side enters the space 27 from the gas discharge port 26, passes through the notch 29, flows through the cooling passage 39, cools the tongue portion 35, and cools the tongue portion 35.
leaks to the outside.

[Effects of the Invention] As described above, according to the present invention, the cooling passage is provided in the tongue portion of the turbine housing, and the gas after the bearing action of the hydrostatic gas bearing is guided into the cooling passage. This gas makes it possible to cool the tongue portion, which is subjected to a large heat load, thereby reducing the heat load on the tongue portion and improving durability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a turbocharger according to an embodiment of the present invention, and FIG. 2 is a scaled-down sectional view taken along the line 1--2 of FIG. 1... Turbine housing 3... Turbine 7.
... Compressor 9 ... Shaft 26 ... Gas discharge port 35 ... Tongue section 39 ... Cooling passage Fig. 2

Claims (1)

[Claims] A turbine housing in which the turbine is housed in a hydrostatic gas bearing-type turbine device that levitates the shaft by supplying high-pressure gas to the outer periphery of a shaft that connects an exhaust-driven turbine and a compressor that sends compressed air to an engine. A turbine device characterized in that a cooling passage communicating with a gas discharge port of the hydrostatic gas bearing is provided in the tongue portion of the hydrostatic gas bearing.