JPH11229886A - Turbocharger sealing unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leakage of exhaust gas outside over an extended period of time even if a sealing becomes permanently deformed by heat from the exhaust gas, since the peripheral surface of the seal ring 17 pressure-contacts a plate 1 and a housing 2 by exhaust gas pressure. SOLUTION: In this sealing unit, an exhaust gas duct 3 within a turbine housing 2 is sealed from the outside by a ring shaped plate 1. Loop-like sealing spaces 15, 16 are formed between the turbine housing 2 and the plate 1. In addition, a seal ring 17 with a substantially U-shaped cross-section is installed within each sealing space. The peripheral surface of the seal ring 17 contacts the turbine housing 2 and the plate 1. Also, the top portion of the seal ring 17 is inclined to the outside so that pressure from the exhaust gas from the turbine housing 2 acts on the inside of the top portion of the seal ring 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbocharger used for an engine, and more particularly, to a turbocharger sealing device having a variable nozzle.

[0002]

2. Description of the Related Art Conventionally, a turbocharger provided with a variable nozzle generally has a turbine housing, a ring-shaped plate mounted on the turbine housing to seal an exhaust gas passage in the turbine housing from the outside, and a plate passing through the plate. A pin rotatably supported by each of the pins, a nozzle attached to an end of each pin on the exhaust gas passage side, and a lever attached to an end of each pin on the outside opposite to the exhaust gas passage side, A drive ring engaged with each lever, and by rotating each drive nozzle by rotating the drive ring, the flow path area between adjacent nozzles can be adjusted. Fairness 7-
No. 13468).

[0003]

The exhaust gas flowing through the exhaust gas passage leaks to the outside through the contact surface between the plate and the turbine housing. Conventionally, the exhaust gas leaks to the outside. It has been difficult to reliably prevent this for a long time. For example, even when a metal O-ring is provided between the contact surfaces, the exhaust gas temperature is 600 ° C. or higher, so that the O-ring is easily sagged and has a disadvantage of lacking durability. The present invention has been made in view of such circumstances, and provides a seal device for a turbocharger capable of effectively preventing exhaust gas in a turbine housing from leaking to the outside for a long period of time.

[0004]

According to the present invention, in the above-described turbocharger, an annular seal space is formed between the turbine housing and the plate, and a seal ring having a substantially U-shaped cross section is formed in the seal space. And the peripheral surface of the seal ring is brought into contact with the turbine housing and the plate, and the pressure of the exhaust gas from the turbine housing acts on the inside of the seal ring facing outward. is there.

[0005]

According to the above construction, the exhaust gas to be leaked to the outside from the exhaust gas passage in the turbine housing acts on the inside of the seal ring having a substantially U-shaped cross section, and its peripheral surface is formed on the turbine housing and the plate. Because of the pressure contact, the leakage is effectively prevented by the seal ring. The seal ring has a simple shape of a substantially U-shaped cross section, and its peripheral surface is pressed against the turbine housing and the plate by the pressure of the exhaust gas as described above. However, even if the exhaust gas is exhausted, it is possible to prevent the exhaust gas from leaking to the outside for a long time.

[0006]

1 to 3, a ring-shaped plate 1 is fixed to a turbine housing 2 of a turbocharger, and is formed in the turbine housing 2 by the plate 1. FIG. The swirled exhaust gas passage 3 is sealed from the outside. A large number of pins 4 are rotatably supported on the same circumference of the plate 1 respectively. Each of the pins 4 is arranged in the axial direction of the ring-shaped plate 1, penetrates the plate 1, and has a nozzle 5 at an end on the exhaust gas passage 3 side. As is well known in the art, each nozzle 5 is disposed at an inlet of a turbine chamber 6, and by rotating each nozzle 5 to control a flow path area between adjacent nozzles 5, a turbine blade provided in the turbine chamber 6 is provided. The flow rate of the exhaust gas to the vehicle 7 can be controlled.

[0007] One end of a lever 8 is attached to the outer end of each of the pins 4, and the other end of each lever 8 is directed radially outward of the ring-shaped plate 1. A drive ring 9 is mounted on the plate 1 at a position adjacent to each lever 8 so as to be rotatable about the center of the plate 1. Further, an engaging portion 9a composed of the same number of recesses as the levers 8 is formed on the outer periphery of the drive ring 9, and a columnar engaging portion protruding toward the drive ring 9 is formed at the other end of each lever 8. 8a are formed so as to protrude, and the engaging portions 8a of the respective levers 8 are respectively engaged with the engaging portions 9a of the drive ring 9. The drive ring 9 is linked to an actuator (not shown) as is well known in the art, and is reciprocally rotated by a predetermined amount by the actuator.

Further, annular seal spaces 15 and 16 are formed between the outer peripheral surface of the plate 1 and the contact surface between the turbine housing 2 and the inner peripheral surface of the plate 1 and the contact surface between the turbine housing 2. And a seal ring 17 having a substantially U-shaped cross section in each seal space.
Is provided. The seal ring 17 is, for example, 0.2
It is manufactured from a thin heat-resistant steel plate such as SUS304 having a thickness of mm, and has a cylindrical portion 17a that comes into contact with one of the plate 1 and the turbine housing 2 as shown in an enlarged view in FIG. In the illustrated embodiment, as shown in FIG. 1, the cylindrical portion of the seal ring 17 in the seal space 15 contacts the turbine housing 2, and the cylindrical portion of the seal ring 17 in the seal space 16 contacts the plate 1. ing.

The seal ring 17 has a curved portion 17b which is bent substantially in a U shape from the outside of the cylindrical portion 17a, that is, from the end opposite to the exhaust gas passage 3.
The distal end portion 17c of the curved portion 17b comes into contact with the other of the plate 1 and the turbine housing 2. Therefore, the substantially U-shaped seal ring 17
Is in contact with the plate 1 and the turbine housing 2, the top 17d of the curved portion 17b of the seal ring 17 faces outward, and the inside faces toward the exhaust gas passage 3 side. And inside this seal ring 17,
Exhaust gas pressure acts through an orifice passage 18 formed between the plate 1 and the turbine housing 2. At this time, the seal ring 17
Each contact surface between the plate 1 and the turbine housing 2 where the cylindrical portion 17a and the curved portion 17b are in contact with each other is a cylindrical surface extending in the axial direction of the ring-shaped plate 1, and the curved portion 17b The distal end portion 17c is inclined with respect to the cylindrical surface in a free state.

In the above configuration, when the drive ring 9 is rotated by the actuator, the drive ring 9
The levers 8 are simultaneously swung in the same direction via the engaging portions 8a of the levers 8 engaged with the engaging portions 9a. When the levers 8 are simultaneously swung in the same direction,
Thus, the nozzles 5 are simultaneously rotated in the same direction via the pins 4, so that the flow passage area between the adjacent nozzles 5 is controlled as described above. The exhaust gas flowing through the exhaust gas passage 3 flows into the seal spaces 15 and 16 via the orifice passage 18, and the pressure acts on the inside of the seal ring 17. as a result,
The cylindrical portion 17a of the seal ring 17 and the tip portion 17c of the curved portion 17b come into pressure contact with the plate 1 and the turbine housing 2 to seal the portion well,
Exhaust gas is prevented from leaking to the outside from the contact surface between the plate 1 and the turbine housing 2.
Further, the seal ring 17 has a simple shape with a substantially U-shaped cross section, and its peripheral surface is pressed against the plate 1 and the turbine housing 2 by the pressure of the exhaust gas as described above. Even if the exhaust gas 17 is heated by the exhaust gas, it is possible to prevent the exhaust gas from leaking to the outside for a long period of time.

The term "substantially U-shaped" is used to mean a V-shaped or U-shaped cross section.

[0012]

As described above, according to the present invention, it is possible to effectively prevent the exhaust gas in the turbine housing from leaking to the outside for a long period of time.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part showing a first embodiment of the present invention.

FIG. 2 is a right side view of a plate portion.

FIG. 3 is a left side view of a plate portion.

FIG. 4 is an enlarged sectional view of a seal ring 17;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Plate 2 ... Turbine housing 3 ... Exhaust gas passage 4 ... Pin 5 ... Nozzle 8 ... Lever 9 ... Drive ring 15, 16 ... Seal space 17 ... Seal ring 18 ... Orifice passage

Claims (4)

[Claims] 1. A turbine housing, a ring-shaped plate attached to the turbine housing to seal an exhaust gas passage in the turbine housing from the outside, a pin that penetrates the plate and is rotatably supported, respectively. A nozzle attached to an end of the pin on the exhaust gas passage side, a lever attached to an end of the pin on the outside opposite to the exhaust gas passage side, and a drive ring engaged with each lever; In the turbocharger in which each of the nozzles is rotated by rotating the drive ring, an annular seal space is formed between the turbine housing and the plate, and a substantially U-shaped cross section is formed in the seal space.
A seal ring having a V-shape is disposed, and the peripheral surface of the seal ring is brought into contact with the turbine housing and the plate. A sealing device for a turbocharger, characterized in that: 2. The turbocharger sealing device according to claim 1, wherein an inside of the seal ring communicates with an exhaust gas passage via an orifice passage. 3. The seal ring includes a tubular portion that contacts one of the turbine housing and the plate, and a curved portion that is bent in a substantially U-shape from an outer end of the tubular portion. The turbocharger sealing device according to claim 1 or 2, wherein a tip portion of the curved portion contacts the other of the turbine housing and the plate. 4. A contact surface between the turbine housing and the plate, at which the cylindrical portion and the curved portion of the seal ring come into contact, is a cylindrical surface extending in the axial direction of the ring-shaped plate. The sealing device for a turbocharger according to claim 3, wherein a tip portion of the portion is slanted with respect to the cylindrical surface in a free state.