JP2010096120A - Bearing device for turbocharger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a turbocharger preventing occurrence of malfunction of rolling bearings caused by foreign matter. <P>SOLUTION: This bearing device for the turbocharger includes: a housing 11 holding rolling bearings 4, 5 and having an oil supply passage P leading engine oil to the rolling bearings; and an oil filter device 13 provided with an oil filter 17, and a bypass oil passage P1 constructed around an engine oil introducing port in the housing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bearing device that supports a rotating shaft of a turbocharger (supercharger) mounted on a vehicle such as an automobile.

  A turbocharger is a device that rotates a turbine by exhaust gas from an engine, drives a compressor by the rotation, and compresses air for intake to the engine. The rotating shaft of such a turbocharger is rotatably supported by a rolling bearing. However, since the rotational speed is very large (for example, 200,000 times per minute), oil lubrication of the rolling bearing is necessary. In view of this, there has been proposed a bearing device in which an oil supply path is provided in a housing that holds a rolling bearing, and engine oil is supplied to the rolling bearing (see, for example, Patent Documents 1 and 2).

JP 2002-54449 A JP 2002-54451 A

However, if the user neglects to change the engine oil, foreign matters such as sludge are generated in the engine oil due to deterioration. When such foreign matter is caught in the raceway of the rolling bearing, problems such as abnormal noise occur. Moreover, if it uses in such a state, the lifetime of a rolling bearing will become short.
In view of such a conventional problem, an object of the present invention is to provide a turbocharger bearing device that prevents the occurrence of problems in a rolling bearing due to foreign matter.

  A turbocharger bearing device according to the present invention includes a pair of rolling bearings rotatably supporting a rotating shaft having a turbine-side impeller and a compressor-side impeller at both ends, and holds the rolling bearing, and engine oil is supplied to them. A housing having an oil supply passage for guiding, an inner pipe portion that forms an inlet for engine oil, and an outer pipe portion on the outside of the housing; the engine oil introduced into the inner pipe portion on the outer surface side of the inner pipe portion; A bypass oil passage is configured to move the inner surface side of the outer tube portion in one axial direction, and further move the outer surface side of the outer tube portion in the other axial direction, and an oil filter is disposed in the middle of the bypass oil passage. And an intervening oil filter device.

  In the turbocharger bearing device configured as described above, the foreign matter can be removed by the oil filter, so that it is possible to prevent the rolling bearing from being defective due to the foreign matter. Further, since the oil filter device is provided with a bypass oil path around the engine oil inlet, the occupied space is small.

In the turbocharger bearing device described above, the oil filter may be cylindrical, and the engine oil may pass in the axial direction thereof.
In this case, a certain filtration effect can be ensured by the length of the oil filter in the axial direction.

  According to the turbocharger bearing device of the present invention, foreign matter can be removed by the oil filter, so that troubles of the rolling bearing can be prevented and the life can be extended. Further, since the oil filter device is provided with a bypass oil passage around the engine oil introduction port, the occupied space is small, and therefore a compact turbocharger bearing device can be obtained.

  FIG. 1 is a cross-sectional view of a turbocharger bearing device according to an embodiment of the present invention. In the figure, a turbine side impeller 2 and a compressor side impeller 3 are attached to both ends of the rotary shaft 1, respectively. The turbine side impeller 2 is rotated by exhaust gas from the engine, and the compressor side impeller 3 compresses the air for intake to the engine by the rotation. The rotating shaft 1 is rotatably attached to a substantially cylindrical inner housing 6 by a pair of rolling bearings (angular ball bearings) 4 and 5. Preloads due to the elastic force of the compression springs 7 are applied to the outer rings of the rolling bearings 4 and 5 in the axial direction via the sleeves 8 and 9, respectively.

The inner housing 6 is held by an outer housing 10, and both form a housing 11 that holds the rolling bearings 4 and 5. The outer housing 10 is formed with an oil supply path (details will be described later) for guiding engine oil as lubricating oil, a discharge outlet 1b for discharge, and a jacket 10a for passing cooling water.
Further, in order to seal the radial gap between the vicinity of the turbine side end 10 b of the outer housing 10 and the rotary shaft 1, a piston ring type seal 12 is provided in the circumferential groove 1 a formed on the outer periphery of the rotary shaft 1. It is installed.

FIG. 2 is an enlarged cross-sectional view of a part of FIG. In FIG. 2, the arrow indicates the direction in which engine oil flows.
In FIG. 2, the outer housing 10 is formed with a mounting hole 10 c that forms a cylindrical space. An oil filter device 13 is attached to the attachment hole 10c. The oil filter device 13 includes an oil filter cartridge 14 and an inner pipe portion 15 that constitutes an engine oil inlet.

  The oil filter cartridge 14 includes a bottomed cylindrical (cup-shaped) case or outer tube portion 16 (outer tube portion with respect to the inner tube portion 15) as a frame, and a cylindrical oil filter 17 attached to the outer periphery thereof. It is constituted by. Both ends of the oil filter 17 in the axial direction are supported by upper and lower support portions 16a formed to project from the outer tube portion 16 in a bowl shape. A plurality of notches or holes for allowing oil to pass in the axial direction are formed in the support portion 16a. The oil filter 17 is sandwiched between the inner wall surface of the mounting hole 10 c and the outer tube portion 16.

On the other hand, the inner tube portion 15 includes a cylindrical tube portion 15a, a mortar-shaped bottom portion 15b, and a flange portion 15c that extends radially outward from the upper end of the tube portion 15a. The tube portion 15 a and the bottom portion 15 b are disposed coaxially with the outer tube portion 16 with a gap between the tube portion 15 a and the bottom portion 15 b with the inner wall of the outer tube portion 16. A hole 15d is formed in the center of the bottom 15b. The flange portion 15 c is attached to the outer housing 10 by a bolt 18.
A hole 10d is formed at the center of the bottom of the mounting hole 10c. A lateral hole 10e extending parallel to the axial direction of the rotary shaft 1 is formed so as to communicate with the hole 10d. Further, a vertical hole 10f is formed in the radial direction so as to communicate with the horizontal hole 10e.

  The engine oil introduced into the inner pipe portion 15 is given hydraulic pressure by an oil feed pump (not shown). The introduced engine oil exits from the hole 15d in the bottom portion 15b and passes through the gap between the bottom of the outer tube portion 16 and the inner tube portion 15 radially outward. Further, the engine oil passes through the gap between the inner tube portion 15 and the inner tube portion 15 on the inner surface side of the outer tube portion 16 in the axial direction upward, and exits from the upper end of the outer tube portion 16 to the outside. The engine oil that has come to the outside passes through the oil filter 17 in the gap between the outer surface of the outer tube portion 16 and the inner wall of the mounting hole 10c downward in the axial direction, and between the bottom surface of the mounting hole 10c and the outer tube portion 16 Is moved radially inward. And it flows out from the hole 10d to the horizontal hole 10e.

  By the oil filter device 13 as described above, a bypass oil path P1 is formed for moving the engine oil in both directions in the axial direction from when it is discharged from the inner pipe portion 15 until it flows into the lateral hole 10e. As a result, a long stroke of engine oil can be created in a relatively narrow space. And the foreign material contained in engine oil is removed by the oil filter 14 interposing in the middle of the process.

  On the other hand, the engine oil that has flowed out into the horizontal hole 10 e further passes through the vertical hole 10 f and reaches the outer surface of the inner housing 6. The oil passage P2 constituted by the horizontal hole 10e and the vertical hole 10f constitutes a main part of the oil supply passage P together with the bypass oil passage P1. The engine oil that has reached the outer surface of the inner housing 6 reaches both ends of the inner housing 6 in the axial direction, and lubricates the rolling bearings 4 and 5. The engine oil is also supplied through a small hole (not shown) formed in the inner housing 6 itself through a hole 8a of the sleeve 8 and the like.

In the turbocharger bearing device configured as described above, foreign matters can be removed by the oil filter 17, so that troubles of the rolling bearings 4 and 5 due to the foreign matters can be prevented. Therefore, it contributes to extending the life of the rolling bearings 4 and 5.
In addition, since the oil filter device 13 is provided with a bypass oil passage around the inlet of the engine oil, it occupies a small space, and thus can be a compact turbocharger bearing device. For example, the oil filter device 13 can be easily attached to a conventional turbocharger bearing device without the oil filter device 13.
Further, by incorporating the oil filter 17 in the turbocharger bearing device, it is not necessary to provide an oil filter outside, which contributes to space saving around the device.

  Further, since the oil filter 17 is cylindrical, a certain filtration effect can be ensured by the length in the axial direction. That is, a dense filter is good for enhancing the filtration effect, but this is easily clogged. Conversely, a coarse filter is less likely to be clogged, but the filtration effect is poor. However, even if the filter is relatively coarse, if it is formed into a cylindrical shape and filtered with a long permeation stroke in its axial direction, a certain filtering effect can be obtained and it is difficult to clog.

  The oil filter cartridge 14 needs to be replaced periodically. At the time of replacement, the bolt 18 is removed, and the entire oil filter device 13 is removed from the outer housing 10. FIG. 3 is a cross-sectional view of the turbocharger bearing device with the oil filter device 13 removed. FIG. 4 is a cross-sectional view showing the oil filter device 13 removed (or before being attached). In this way, the oil filter device 13 can be easily removed. Therefore, the oil filter cartridge 14 can be easily replaced. Note that only the oil filter cartridge 14 may be removed and replaced from the oil filter device 13 shown in FIG. 4, or the entire oil filter device 13 may be replaced.

It is sectional drawing of the bearing apparatus for turbochargers which concerns on one Embodiment of this invention. It is sectional drawing to which a part of FIG. 1 was expanded. It is sectional drawing of the bearing apparatus for turbochargers which removed the oil filter apparatus. It is sectional drawing which shows the oil filter apparatus removed (or before attaching).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Turbine side impeller 3 Compressor side impeller 4,5 Rolling bearing 6 Inner housing 10 Outer housing 11 Housing 13 Oil filter device 15 Inner pipe part 16 Outer pipe part 17 Oil filter P1 Detour oil path P2 Oil path P Oil supply path

Claims (2)

A pair of rolling bearings rotatably supporting a rotating shaft having a turbine side impeller and a compressor side impeller at both ends;
A housing for holding the rolling bearing and having an oil supply path for guiding engine oil to the rolling bearing;
An inner pipe part forming an engine oil inlet and an outer pipe part outside the inner pipe part, and the engine oil introduced into the inner pipe part is on the outer surface side of the inner pipe part and on the inner surface side of the outer pipe part And an oil filter device in which an oil filter is interposed in the middle of the bypass oil path, and a bypass oil path is configured to move the outer surface side of the outer pipe portion to the other axial direction. A turbocharger bearing device.   The turbocharger bearing device according to claim 1, wherein the oil filter has a cylindrical shape, and engine oil passes in an axial direction thereof.

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