JPH08135458A - Oil seal structure for supercharger - Google Patents

Abstract

PURPOSE: To prevent leakage of oil in a supercharger by rotatably providing a collar on a driving shaft in the vicinity of a compressor wheel in the supercharger integratedly with the driving shaft, and arranging a retainer on the outer circumferential side of the collar through a seal ring. CONSTITUTION: In a collar 11, a retainer 12, and a deflector 13 as a mechanism for preventing oil from leaking to a compressor wheel side in a turbo charger 1, a groove 17 is formed o the collar 11, a seal ring 18 is mounted, and slinger 19 is provided on the outer circumference of the collar 11. A rib 21 is provided adjacently to the slinger 19, the first surface 22 of the inside of the rib 21 and the second surface 23 of a penetrating hole 14 side in the deflector 13 are formed nearly flush, and an annular and flat plate shaped seal lip 24 is mounted on the second surface 23 so as to make extend to the first surface 22. Since the seal lip 24 abuts on the first surface 22, it is possible to prevent inner side oil from leaking to the slinger 19 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supercharger oil seal structure represented by, for example, a turbocharger.

[0002]

2. Description of the Related Art Conventionally, in a turbocharger, a turbine wheel and a compressor wheel are connected by a drive shaft. When the turbine wheel rotates due to the pressure of the exhaust gas, the rotation is transmitted to the compressor wheel via the drive shaft, and the air is supercharged into the combustion chamber. In the turbocharger, the drive shaft is lubricated with oil for smooth rotation.

However, part of this oil may be sucked by the negative pressure in the intake passage, leak to the compressor wheel side, and be consumed by the engine through the intake passage.

As a technique for solving such a problem,
For example, the one disclosed in Japanese Utility Model Publication No. 60-116035 is known. In this technique, as shown in FIG. 5, an oil leakage prevention device 51 is provided in the turbocharger. The oil leakage prevention device 51 includes a collar 52, a retainer 53, and a deflector 54. The collar 52 has a substantially cylindrical shape, is fitted into a drive shaft 55 near a compressor wheel (not shown), and rotates together with the drive shaft 55. Also, the retainer 53
Is fixed inside a center housing (not shown) that surrounds the drive shaft 55. Further, the deflector 54 is on the opposite side of the retainer 53 from the compressor wheel,
That is, it is attached to the inner side (right side in the drawing) and has a disc shape, and a circular through hole 56 is formed in the center.

A flange-shaped slinger 57 is provided on the outer periphery of the collar 52. A first seal ring 60 is provided between the pair of ribs 58, 59 formed on the collar 52, and basically the seal ring 60 seals the retainer 53 and the collar 52. Has become. Further, the collar 5 near the deflector 54
A pair of ribs 61, 62 are formed on the second rib 6, and both ribs 6 are formed.
A second seal ring 64 is provided in the groove 63 formed by 1, 62. This seal ring 64
Are arranged at positions just corresponding to the through holes 56 of the deflector 54. Therefore, this second seal ring 6
4, the inner wall surface of the through hole 56 of the deflector 54 and the groove 63 of the collar 52 are sealed.

Therefore, according to the above conventional technique, basically, the second seal ring 64 can suppress the oil from leaking to the left in the drawing. Further, the oil that has leaked to some extent is scattered by the slinger 57, is guided downward by the deflector 54, and is discharged. Further, the first seal ring 60 regulates oil leakage to the compressor wheel. Therefore, it is possible to suppress oil leakage as a whole.

[0007]

However, as the second seal ring 64 in the above-mentioned prior art, a C ring or the like made of metal is adopted. Therefore, the second seal ring 64 and the deflector 54 can be reliably sealed. On the other hand, if the second seal ring 64 and the collar 52 (which rotates integrally with the drive shaft 55) are sealed and frictional force acts between them,
The rotation of the drive shaft 55 is hindered. Therefore, in practice, as shown in FIG. 6, it is unavoidable to provide a predetermined gap 65 between the second seal ring 64 and the groove 63 of the collar 52 to prevent the frictional force from acting. Therefore, a part of the oil may flow from the right side to the left side in the drawing through the gap 65, and the basic sealing performance may not be sufficiently ensured. As a result, there have been cases where the effects of the invention of the prior art are not fully exhibited.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide an oil seal structure for a supercharger which can almost certainly prevent oil leakage in the supercharger. is there.

[0009]

To achieve the above object, in the present invention, a compressor wheel and a turbine wheel are provided at both ends, and a drive shaft is rotatably supported in a housing, and the compressor. A substantially cylindrical collar fitted to a drive shaft near the wheel and rotating integrally with the drive shaft, and a retainer mounted inside the housing and disposed on the outer periphery of the collar via a seal ring. And a slinger that is provided in a substantially flange shape with respect to the collar, is attached to the turbine wheel side with respect to the slinger for scattering oil in the outer peripheral direction, and a circular penetrating hole through which the collar is inserted. A hole having a hole and a deflector for guiding the oil scattered by the slinger downward. A oil seal structure of the machine,
A first surface on the turbine wheel side that is provided integrally with or separately from the slinger and is orthogonal to the drive shaft, and a second surface on the through hole side on the turbine wheel side of the deflector. And make it almost flush,
The gist of the invention is that one of the first surface and the second surface is provided with a seal lip made of an elastic member extending to the other surface.

[0010]

With the above arrangement, the substantially cylindrical collar fitted on the drive shaft near the compressor wheel of the supercharger rotates together with the drive shaft.
A retainer is disposed inside the housing surrounding the drive shaft via a seal ring on the outer periphery of the collar. Therefore, the collar and the retainer are basically sealed by the seal ring.

Further, the slinger provided in a substantially flange shape with respect to the collar scatters oil in the outer peripheral direction as the drive shaft and the collar rotate. Further, the oil scattered by the slinger is guided downward by a deflector attached to the retainer on the turbine wheel side and having a collar inserted through a circular through hole formed at the center.

In the present invention, the first surface on the turbine wheel side, which is provided integrally with or separately from the slinger and is orthogonal to the drive shaft, and the second surface on the turbine wheel side of the deflector, which is on the through hole side, are provided. Is almost flush with each other, and one of the first surface and the second surface is
A seal lip made of an elastic member extending to the other surface is provided. Therefore, when the pressure in the housing is equal to the pressure between the deflector and the seal ring, the seal lip provided on one surface abuts the other surface with a surface pressure of substantially zero. Therefore, the oil inside the seal lip is blocked by the seal lip and is unlikely to leak to the slinger and the seal ring.

Therefore, according to the present invention, basically, the oil leakage is first suppressed by the seal lip. Further, the oil on the slinger side is guided downward by the action of the slinger and the deflector, and oil leakage is suppressed. Further, finally, the seal ring suppresses the oil from leaking to the compressor wheel side.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which an oil seal structure for a supercharger according to the present invention is embodied in a turbocharger will be described in detail below with reference to the drawings.

FIG. 2 is a partial sectional view showing a part of a turbocharger 1 as a supercharger mounted on a vehicle in the present embodiment, and FIG. 1 is a partial sectional view showing a main part thereof. As shown in these figures, the turbocharger 1
Includes a compressor wheel 2, a turbine wheel (not shown), and a drive shaft 3 connecting both of them. The drive shaft 3 is provided in the housing 4. When the turbine wheel rotates due to the pressure of the exhaust gas, the rotation is transmitted to the compressor wheel 2 via the drive shaft 3 to supercharge the air into the combustion chamber of the engine.

Oil is supplied into the housing 4, and the drive shaft 3 is lubricated by the oil. That is, the oil flows through the oil supply passage 5 formed in the housing 4 toward the floating bearing 6, the thrust bearing 7 and the thrust collar 8 arranged inside the housing 4. With such a configuration, the drive shaft 3 is smoothly rotated. However, since this oil supply structure is a known technique, a detailed description thereof will be omitted.

On the other hand, in this embodiment, a mechanism is provided for preventing the oil from leaking to the compressor wheel 2 side. That is, the oil leakage prevention mechanism includes the collar 11, the retainer 12, and the deflector 13. The collar 11 has a substantially cylindrical shape,
It is fitted into the drive shaft 3 near the compressor wheel 2 and rotates together with the drive shaft 3. Further, the retainer 12 is arranged on the outer periphery of the collar 11 and is fixed inside the housing 4.
Further, the deflector 13 has a disc shape, and is attached to the turbine wheel side, that is, the inner side (the right side in the drawing) with respect to the outer peripheral edge of the retainer 12. This deflector 1
A circular through hole 14 is formed in the center of the hole 3, and the collar 11 is inserted into the through hole 14.

A pair of ribs 15 and 16 are formed on the outer periphery of the collar 11 on the compressor wheel 2 side (left side in the figure), and a groove 17 is formed by these ribs 15 and 16. A metal seal ring 18 is provided in the groove 17, and basically, the seal ring 18 seals between the seal ring 18 and the retainer 12, and thus seals between the retainer 12 and the collar 11. It has become.

A flanged slinger 19 is provided on the outer periphery of the collar 11 between the retainer 12 and the deflector 13. Furthermore, the deflector 1
3, a guide portion 13a extending downward is integrally formed. The rotation of the slinger 19 causes the oil to be scattered outward, and most of it is deflected by the deflector 1.
It is supposed to hit 3. The oil that hits the deflector 13 is then guided downward through the guide portion 13a and discharged to an oil return hole (not shown).

Next, a characteristic part of this embodiment will be described. As shown in FIG. 3, the collar 11 is provided with ribs 21 adjacent to the slinger 19. A first surface 22 orthogonal to the drive shaft 3 is formed inside the rib 21 (on the right side in the drawing). The first surface 22 is located inside the deflector 13 (right side in the figure).
And the surface on the side of the through hole 14 (hereinafter, this surface will be referred to as “second surface”).
It is almost the same as 23). Further, a seal lip 24 made of an annular elastic member (rubber in this embodiment) is attached to the second surface 23 so as to extend to the first surface 22.

As shown in FIGS. 2 and 4, a plurality of protrusions 25 are formed so as to project inwardly (rightward in the figure) in a circular arc shape on the portion of the retainer 12 excluding the lower portion. These ridges 25 guide the oil downward when the oil scattered by the slinger 19 hits the inner wall of the retainer 12.

Next, the operation and effect of the oil seal structure of the turbocharger 1 configured as above will be described. According to the above conventional technique, first, when the pressure in the housing 4 is equal to the pressure between the deflector 13 and the seal ring 18 (hereinafter, referred to as the pressure on the compressor wheel 2 side), the pressure is provided on the second surface 23. The seal lip 24 contacts the first surface 22 with a surface pressure of substantially zero. Therefore, inside the seal lip 24 (right side in the figure)
The oil is blocked by the seal lip 24 and is unlikely to leak to the slinger 19 and the seal ring 18 side.

When the pressure inside the housing 4 becomes relatively large, the seal lip 24 is forced to move to the first position by the pressure.
Strongly abuts the surface 22 of the. That is, the seal lip 24
Exhibits a self-sealing function and seals between the deflector 13 and the rib 21 of the collar 11. For this reason, oil leakage to the slinger 19 side is reliably suppressed.

Further, when some oil leaks to the slinger 19 side, the oil is scattered to the outside by the rotation of the slinger 19. Then, the oil hitting the deflector 13 is guided downward by the gravity along the wall surface,
It falls down along the guide portion 13a. After that, the oil is discharged toward the oil return hole. On the other hand, when the scattered oil hits the wall surface of the retainer 12, the oil drops downward along the plurality of protrusions 25. For this reason, even if some oil leaks toward the slinger 19, the oil is still present in the slinger 19, the deflector 13 and the ridge 2.
By the action of 5, the oil is guided downward, and the inflow of oil to the seal ring 18 side is suppressed.

Furthermore, finally, the seal ring 18 reliably suppresses the leakage of oil to the compressor wheel 2 side. As a result, oil leakage as a whole can be reliably suppressed.

In addition, in this embodiment, as described above,
When the pressure in the housing 4 is equal to the pressure on the compressor wheel 2 side, the seal lip 24 provided on the second surface 23 contacts the first surface 22 with a surface pressure of substantially zero. Further, since some oil is interposed between the seal lip 24 and the second surface 22, the two are always lubricated with oil. Therefore, the rotating collar 1
Almost no frictional force acts between 1 and the fixed seal lip 24. As a result, it is possible to suppress the wear of the seal lip 24 as much as possible, and it is possible to endure long-term use. Further, since the frictional force hardly acts between them, the rotation of the drive shaft 3 is not so hindered. As a result, turbocharger 1
It is possible to prevent deterioration of the responsiveness (turbo response) of itself.

The present invention is not limited to the above embodiment, but may be configured as follows, for example. (1) In the above embodiment, the seal lip 2 is provided on the second surface 23.
However, the seal lip 24 may be attached to the first surface 22 so as to extend to the second surface 23.

In the above embodiment, the rib 21 is provided so as to be adjacent to the slinger 19, and the first surface 22 and the second surface 23 of the rib 21 are substantially flush with each other. The inner wall surface of the slinger 19 may be the first surface. Further, the slinger 19 and the rib 21 may be provided separately.

(2) The ridge 25 in the above embodiment may be omitted. (3) In the above-described embodiment, the seal lip 24 is made of rubber, but a resin material, a metal (thin film) or the like may be used as long as it has a predetermined elasticity.

(4) Although the slinger 19 is formed integrally with the collar 11 in the above embodiment, it may be provided separately. Further, the diameter of the slinger 19 is not limited to the above embodiment. That is, for example, by making the diameter of the slinger 19 larger than that in the above-described embodiment, it is possible to further suppress the outflow of oil to the seal ring 18 side.

The technical idea which is not stated in the claims of the present invention and which can be understood from the above-mentioned embodiment will be described below together with its effect. (A) In the oil seal structure for a supercharger according to claim 1, guide means for guiding the oil hitting the retainer to the lower side while avoiding the collar (the guide means is, for example, a protrusion). Article) is provided. With such a configuration, it is possible to further prevent oil leakage.

[0032]

As described in detail above, according to the present invention,
It has an excellent effect that it is possible to almost certainly prevent oil leakage in the supercharger.

[Brief description of drawings]

FIG. 1 is a sectional view showing an oil seal structure of a turbocharger.

FIG. 2 is a partial cross-sectional view showing a turbocharger in one embodiment.

FIG. 3 is a cross-sectional view showing a characteristic portion of a turbocharger of one embodiment.

FIG. 4 is a front view showing an inner surface of a retainer according to an embodiment.

FIG. 5 is a cross-sectional view showing an oil seal structure in the related art.

FIG. 6 is an enlarged cross-sectional view showing an oil seal structure in the related art.

[Explanation of symbols]

1 ... Turbocharger as supercharger, 2 ... Compressor wheel, 3 ... Drive shaft, 4 ... Housing, 11
... color, 12 ... retainer, 13 ... deflector, 14 ...
Through hole, 18 ... Seal ring, 19 ... Slinger, 22
... first surface 23, second surface 24, seal lip.

Claims (1)

[Claims] 1. A drive shaft having a compressor wheel and a turbine wheel provided at both ends thereof and rotatably supported in a housing, and a drive shaft near the compressor wheel, fitted into the drive shaft, and integrated with the drive shaft. A rotating substantially cylindrical collar, a retainer mounted inside the housing and disposed on the outer periphery of the collar via a seal ring, and a retainer provided in a substantially flange shape with respect to the collar to allow oil to flow in the outer peripheral direction. And a slinger for scattering to the retainer, a circular through hole that is attached to the turbine wheel side with respect to the retainer, and through which the collar is inserted in the center, and guides the oil scattered by the slinger downward. Is an oil seal structure for a supercharger equipped with a deflector for Or a separate body, and the first surface on the turbine wheel side orthogonal to the drive shaft and the second surface on the through hole side on the turbine wheel side of the deflector are substantially flush with each other. ,
An oil seal structure for a supercharger, wherein one of the first surface and the second surface is provided with a seal lip made of an elastic member extending to the other surface.