JPH09264151A - Turbocharger oil leakage prevention mechanism - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To securely guide the oil blocked by the blocking plate to the discharge hole and eliminate the risk of oil leakage. SOLUTION: A blocking plate 22 for blocking oil scattered from a slinger portion 19a of a bush 19, a central flat plate portion 22b facing the slinger portion and having a central hole for inserting the bush, and an outer portion of the central flat plate portion 22b. Conical portion 2 extending toward the compressor rotor 13 side while reducing the diameter from the peripheral edge
2a, a wall portion extending from the end portion of the conical portion in a direction perpendicular to the axial direction of the shaft and fixed to the housing at an outer peripheral edge portion thereof, and a lower portion of the wall portion and the conical portion. An opening portion 22f formed to open the annular groove 22c formed by the conical portion and the wall portion to the outside, and a part of the central flat plate portion extending so as to extend obliquely outward through the opening portion 22f. The guide tongue piece 22e is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbocharger, and more particularly to an oil leak prevention mechanism for preventing oil from leaking to the compressor rotor side of the turbocharger.

[0002]

2. Description of the Related Art As an oil leakage prevention mechanism for a conventional turbocharger of this type, for example, the actual engine shovel 59-397.
There is one disclosed in Japanese Patent No. 34. In this structure, a shaft that connects a turbine rotor and a compressor rotor is supported in a housing through a radial bearing, a thrust bearing and a bush, and the outer peripheral surface of the bush that rotates integrally with the shaft and the wall portion of the housing. Disposes a seal ring between the compressor rotor and an inner peripheral cylindrical portion of a seal plate fixed with a predetermined gap, and shuts off oil scattered between the seal plate and the thrust bearing. A blocking plate is arranged to prevent oil leakage to the compressor rotor side.

[0003]

According to the above-mentioned conventional oil leakage prevention mechanism, the oil scattered by the rotation of the bush is prevented by the blocking plate, but the oil is prevented from directly entering the seal plate side. The oil that is blocked by the plate drops downwards by passing through the flat plate part of the blocking plate that has a central hole through which the bush is inserted. I couldn't shut it off.

The present invention has been made in view of the above situation, and an object thereof is to reliably guide the oil blocked by the blocking plate to the discharge hole and eliminate the risk of oil leakage.

[0005]

In order to solve the above-mentioned problems, the technical means of the present invention according to claim 1 is to provide a shaft for connecting a turbine rotor and a compressor rotor in a housing with a radial bearing, a thrust bearing and a bush. Between the outer peripheral surface of the bush, which is supported via the shaft and integrally rotates with the shaft, and the inner peripheral cylindrical portion of the seal plate, the wall portion of which is fixed to the housing with a predetermined clearance from the compressor rotor. In the turbocharger, in which a seal ring is disposed on the compressor and a blocking plate for blocking the scattered oil is disposed between the seal plate and the thrust bearing to prevent oil leakage to the compressor rotor side. The bush has a slinger portion extending outward in the radial direction at the end portion on the thrust bearing side and scattered from the slinger portion. The oil blocking plate is a central flat plate portion facing the slinger portion and having a central hole for inserting the bush, and a cone extending from the outer peripheral edge of the central flat plate portion to the compressor rotor side while reducing the diameter. Portion, a wall portion that extends in a direction perpendicular to the axial direction of the shaft from an end portion of the conical portion, and is fixed to the housing at an outer peripheral edge portion thereof, and a lower portion of the wall portion and the conical portion. An opening that opens to the outside of the annular groove formed by the conical portion and the wall, and a portion of the central flat plate portion that extends diagonally outward through the opening. The guide tongue formed locally is provided.

According to the above means, the oil scattered from the slinger portion hits the wall portion of the blocking plate, flows downward through the wall portion axially separated from the flat plate portion through the conical portion, and a part of the oil flows. It is discharged from the opening and the guide tongue to the outside through a concave passage formed between the wall portion and the conical portion. Therefore, oil is prevented from leaking to the compressor rotor side through the center hole of the flat plate portion.

According to a second aspect of the present invention, in the above-mentioned means, a protrusion extending radially outward is provided at an end portion of an inner peripheral cylindrical portion of the seal plate extending toward the radial bearing and the thrust bearing. A portion is provided, and an annular groove is formed between the protruding portion and the wall portion.

According to this means, even if the oil leaks from the center hole of the flat plate portion to the compressor rotor side, the oil scattered due to the centrifugal force is lowered through the annular groove between the projecting portion and the wall portion. It is possible to prevent the oil from leaking to the seal ring side.

According to a third aspect of the present invention, the shaft connecting the turbine rotor and the compressor rotor is supported in the housing through a radial bearing, a thrust bearing and a bush, and rotates integrally with the shaft. A seal ring is arranged between the outer peripheral surface of the bush and the inner peripheral cylindrical portion of the seal plate, the wall portion of which is fixed to the compressor rotor with a predetermined gap in the housing. In a turbocharger in which oil leakage is prevented, a protrusion extending radially outward is provided at an end of an inner peripheral tubular portion of the seal plate extending toward the radial bearing and the thrust bearing, and the protrusion is That is, an annular groove is formed between the wall and the wall.

According to this means, the oil scattered by the bush rotating with the shaft can be prevented from falling along the wall portion and the annular groove of the seal plate and entering the seal ring side.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an oil leakage prevention mechanism for a turbocharger according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention. In FIG. 1, a pair of shaft holes 10a is formed in a housing 10 made of cast iron or the like, and a shaft 30 is rotatably supported in the shaft holes 10a via radial bearings 15 and 16. The radial bearings 15 and 16 have a shaft hole 1
It is rotatably fitted in the shaft 0a and its axial movement toward the mutually facing sides is restricted by a snap ring. The radial bearing 16 is restricted from moving rightward in the drawing by a large-diameter portion formed on the outer periphery of the shaft 30. A small diameter portion is formed on the left side of the shaft 30 to which the radial bearing 15 is fitted in the drawing, and the small diameter portion is formed at the end portion on the right side of the drawing at the one end surface of the radial bearing 15 or the step portion of the shaft 30. A cylindrical bush 17 having a contacting flange is formed. A bush 19 having a slinger portion formed at the right end of the bush 17 is fitted to the left side of the bush 17 in the figure. An oil seal 20 is fitted in an annular groove formed on the outer circumference of the bush 19, and the shaft hole 10 of the housing 10 is fitted in the oil seal 20.
The inner peripheral cylindrical portion of the seal plate 21, which is press-fitted into the large-diameter hole 10d formed on the left side of a in FIG. The compressor rotor 13 is fitted to the small diameter portion of the shaft 30 on the left side of the bush 19 in the drawing, and is fixed by a bolt fitted to the end of the small diameter portion. This allows
The bushes 17 and 19 are sandwiched between the illustrated right end surface of the compressor rotor 19 and the small-diameter step portion of the shaft 20,
It rotates integrally with the shaft 20 together with the compressor rotor 19. The thrust bearing 1 fixed between the flange portion of the bush 17 and the slinger portion of the bush 19 is a step portion formed on the left side of the large diameter hole 10d of the housing 10 in the drawing.
8 is interposed in the thrust bearing 18, which is formed in the housing 10 and communicates with the oil passage 10b for supplying oil to the radial bearings 15 and 16, and the bush 17
An oil supply hole 18a for supplying oil is formed between the sliding portion of the flange portion of the bush 19 and the slinger portion of the bush 19. A compressor housing 11 having an intake inlet and an intake outlet is airtightly fixed to the housing 10, and a compressor rotor 13 is housed in the compressor housing 11.

The turbine housing 12 is hermetically fixed to the right end of the shaft 30 in the figure. A turbine rotor 14 fixed to the right end of the shaft 30 in the drawing is housed in the turbine housing 12. The turbine housing 12 is formed with an exhaust inlet to which an exhaust manifold of an engine (not shown) is connected and an exhaust outlet to which an exhaust outlet pipe (not shown) is airtightly connected. As a result, the turbine rotor 14 rotates due to the energy of the exhaust gas of the exhaust manifold, whereby the shaft 30 rotates, and together with the shaft 30, the compressor rotor 1
3 rotates and supercharges the intake air of the engine.

In this embodiment, however, the bush 19
At the end of the inner peripheral cylindrical portion of the seal plate 21 that faces the slinger portion 19a, a protruding portion 21a that expands radially outward is formed. The projecting portion 21a is formed in a conical shape so as to follow the shape of a cone portion formed at the connecting portion between the cylindrical portion of the bush 19 and the slinger portion 19a, and the end portion thereof has a predetermined small gap with the slinger portion 19a. Are facing through.

In this embodiment having such a structure, when the above-mentioned turbocharger is operated, oil is supplied between the flange portion of the bush 17 and the slinger portion of the bush 19 through the oil supply hole 18a, The oil is tapered outward by the centrifugal force and on the outer peripheral surface of the slinger portion 19a (the compressor rotor 13 side has a large diameter).
As a result, it is scattered diagonally outward to the left in the figure. The scattered oil hits the inner peripheral surface of the seal plate 21, falls along the inner peripheral surface, and is guided to the discharge hole 10c of the housing 10. Further, while falling along the wall portion of the seal plate 21 and falling along the wall surface, it also falls along the annular groove formed between the wall portion and the protruding portion 21a on the inner peripheral tubular portion, and the housing 10 To the discharge hole 10c. Therefore, it is possible to properly prevent oil from entering the seal ring 20 side from between the end portion of the inner peripheral tubular portion and the slinger portion 19a.

2 to 5 show another embodiment of the present invention. In this embodiment, the same components as those of the embodiment shown in FIG. 1 described above are denoted by the same reference numerals in FIGS. 2 to 5, and the description thereof is omitted.

2 and 3, in this embodiment, the seal plate 21 is different from the embodiment shown in FIG.
The projecting portion 21a formed at the end of the inner peripheral cylindrical portion of the bushing 21 is formed to be short. As shown in FIG. 3, the projecting portion 21a is arranged in parallel with the slinger portion 19a of the bush 19 with a small gap therebetween. It opposes the central flat plate portion 22b of the blocking plate 22 with a small gap.

As shown in FIGS. 4 and 5, the blocking plate 22 faces the slinger portion 19a and the bush 19.
A central flat plate portion 22b having a central hole for inserting
A conical portion 22a extending toward the compressor rotor 13 while reducing its diameter from the outer peripheral edge of the central flat plate portion 22b;
A wall portion extending from the end portion of 2a in a direction perpendicular to the axial direction of the shaft 30 and fixed to the inner hole 21b of the seal plate 21 at an outer peripheral edge portion 22d thereof, and the wall portion and the conical portion 22.
an opening 22f which is formed in a lower part of a and which opens an annular groove 22c formed by the conical portion 22a and the wall portion to the outside;
A guide tongue piece 2 formed by extending a part of the central flat plate portion 22b so as to extend obliquely outward through the opening portion 22f.
2e.

In this embodiment having such a structure, the oil scattered from the slinger portion 19a hits the wall portion of the blocking plate 22, and the wall portion axially separated from the central flat plate portion 22b via the conical portion 22a is hung downward. Flow into the annular groove 22c, a part of which is formed between the wall portion and the conical portion 22a.
Through the (concave passage), the opening 22f and the guide tongue 2
It is discharged from 2e to the outside and guided to the discharge hole 10c. Therefore, the conical portion 22a causes the oil to move to the central flat plate portion 22.
Leakage to the compressor rotor 13 side through the center hole of b is accurately prevented.

Further, even if the oil leaks from the center hole of the central flat plate portion 22b to the compressor rotor 13 side, the oil scattered by the centrifugal force is the protruding portion 2 of the seal plate 21.
It is prevented that the oil drops downward through the annular groove between the wall 1a and the wall and leaks to the seal ring 20 side.

[0021]

As described above, according to the present invention of claim 1, the oil scattered from the slinger portion hits the wall portion of the blocking plate, and the wall portion axially separated from the central flat plate portion through the conical portion. Therefore, it flows downward, and a part of it flows through the concave passage formed between the wall portion and the conical portion and is discharged to the outside through the opening and the guide tongue piece. It is possible to accurately prevent the oil from leaking to the compressor rotor side.

According to the second aspect of the invention, even if the oil leaks from the center hole of the flat plate portion to the compressor rotor side, the oil scattered by the centrifugal force is annular between the projecting portion and the wall portion. Since the oil drops downward through the groove, it is possible to prevent oil from leaking to the seal ring side.
Further, according to the invention of claim 3, the oil scattered by the bush rotating with the shaft falls along the wall portion and the annular groove of the seal plate, so that the oil is prevented from entering the seal ring side. You can

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an oil leakage prevention mechanism for a turbocharger according to the present invention.

FIG. 2 is a sectional view showing another embodiment of an oil leakage prevention mechanism for a turbocharger according to the present invention.

FIG. 3 is an enlarged view of a main part of another embodiment shown in FIG.

FIG. 4 is a side view of the blocking plate in FIG.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

[Explanation of symbols]

 10 Housing 13 Compressor rotor 14 Turbine rotor 15 and 16 Radial bearing 17 Bushing 18 Thrust bearing 19 Bushing 19a Slinger part 20 Seal ring 21 Seal plate 21a Projection part 22 Blocking plate 22a Conical part 22b Central flat plate part 22c Annular groove 22e Guide tongue piece 22f Aperture

Claims (3)

[Claims] 1. A shaft for connecting a turbine rotor and a compressor rotor is supported in a housing via a radial bearing, a thrust bearing and a bush, and an outer peripheral surface of the bush that integrally rotates with the shaft and a wall of the housing. A seal ring is disposed between the compressor rotor and the inner peripheral cylindrical portion of the seal plate, which is fixed with a predetermined gap, and shuts off the oil scattered between the seal plate and the thrust bearing. In the turbocharger in which a blocking plate for preventing oil from leaking to the compressor rotor side is arranged, the bush has a slinger portion extending radially outward at the end portion on the thrust bearing side, and the slinger portion The blocking plate for blocking the oil splashed from is opposed to the slinger portion and A central flat plate portion having a central hole for insertion, a conical portion extending toward the compressor rotor side while reducing a diameter from an outer peripheral edge of the central flat plate portion, and an axial direction of the shaft from an end portion of the conical portion. Extending vertically,
A wall fixed to the housing at its outer peripheral edge,
An opening formed in a lower part of the wall portion and the conical portion and opening an annular groove formed by the conical portion and the wall portion to the outside, and extending obliquely outward through the opening portion. The oil leakage prevention mechanism for a turbocharger according to claim 1, further comprising a guide tongue piece formed by extending a part of the central flat plate portion. 2. A protrusion extending radially outward is provided at an end of an inner peripheral tubular portion of the seal plate extending toward the radial bearing and the thrust bearing, and a protrusion extending radially outward is provided between the protrusion and the wall. An oil leakage prevention mechanism for a turbocharger according to claim 1, wherein an annular groove is formed in the. 3. A shaft for connecting a turbine rotor and a compressor rotor is supported by a housing through a radial bearing, a thrust bearing and a bush, and the outer peripheral surface of the bush that rotates integrally with the shaft and the wall of the housing. In a turbocharger in which a seal ring is disposed between the compressor rotor and an inner cylindrical portion of a seal plate fixed with a predetermined gap to prevent oil leakage to the compressor rotor side. ,
A protrusion extending radially outward is provided at an end of the inner peripheral cylindrical portion of the seal plate extending toward the radial bearing and the thrust bearing, and an annular groove is formed between the protrusion and the wall. The oil leakage prevention mechanism of the turbocharger, which is characterized.