JP7343362B2 - supercharger - Google Patents

Description

The present invention relates to a supercharger.

A variable displacement supercharger is known in which a connecting pin is provided between a nozzle ring provided within a turbine housing and a shroud ring provided so as to surround a turbine impeller provided within the turbine housing. This connecting pin is integrally connected to the nozzle ring and the shroud ring (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2009-243432

By the way, since there is a difference in expansion between the expansion of the nozzle ring (hereinafter referred to as the first nozzle plate) and the expansion of the shroud ring (hereinafter referred to as the second nozzle plate) due to the heat of exhaust gas, the first nozzle plate and Stress corresponding to the expansion difference acts on the connecting pin provided between the second nozzle plate and the connecting pin may be deformed.

More specifically, since the first nozzle plate is often disposed on the side of the bearing housing through which the refrigerant flows, the heat of the exhaust gas is alleviated compared to the second nozzle plate. As a result, a difference in expansion occurs between the first nozzle plate and the second nozzle plate, and stress corresponding to the difference in expansion acts on, for example, the connecting pin and the connecting portion of the second nozzle plate with the connecting pin. As a result, the connecting pin and the second nozzle plate are deformed. If the second nozzle plate is deformed, a malfunction may occur in the operation of the nozzle vanes supported by the first nozzle plate and the second nozzle plate, which may lead to decreased reliability of the supercharger.

Therefore, an object of the present invention is to suppress deformation of the second nozzle plate.

The supercharger according to the present invention includes a ring-shaped first nozzle plate that is arranged on the bearing housing side through which the refrigerant flows and supports one side of the nozzle vane, and a ring-shaped first nozzle plate that is arranged on the turbine housing side where the refrigerant does not flow and supports one side of the nozzle vane. a ring-shaped second nozzle plate that supports another side; and a ring-shaped second nozzle plate that has sliding properties that allow the second nozzle plate to expand and contract in the radial direction; a protrusion that protrudes in the direction of the second nozzle plate and contacts the other to ensure a first clearance between the first nozzle plate and the second nozzle plate; disposed in a second clearance between two nozzle plates, biases the second nozzle plate in the direction toward the bearing housing along the central axis of the second nozzle plate, and presses the second nozzle plate through the second clearance. and an elastic body that seals the inflow of exhaust gas to the downstream side of the nozzle vane .

According to the present invention, deformation of the second nozzle plate can be suppressed.

FIG. 1 is an example of a cross-sectional view of the turbocharger according to the first embodiment. FIG. 2 is a partially enlarged view of the vicinity of the nozzle according to the first embodiment. FIG. 3 is a partially enlarged view of the vicinity of the nozzle according to the second embodiment. FIG. 4 is a partially enlarged view of the vicinity of the nozzle according to the third embodiment. FIG. 5 is a partially enlarged view of the vicinity of the seal ring. FIG. 6 is a partially enlarged view of the vicinity of the nozzle according to the fourth embodiment. FIG. 7 is a partially enlarged view of the vicinity of the nozzle according to the fifth embodiment. FIG. 8 is a partially enlarged view of the vicinity of the nozzle according to the sixth embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is an example of a cross-sectional view of a turbocharger 100 according to the first embodiment. FIG. 2 is a partially enlarged view of the vicinity of the nozzle N according to the first embodiment. The turbocharger 100 is a variable displacement type (variable nozzle type) supercharger. As shown in FIG. 1, the turbocharger 100 includes a compressor 10, a bearing section 20, and a turbine 30. The bearing section 20 connects the compressor 10 and the turbine 30.

Compressor 10 includes a compressor housing 11 . The bearing part 20 includes a bearing housing 21. Turbine 30 includes a turbine housing 31 . The bearing housing 21 is arranged approximately at the center of the turbocharger 100. The compressor housing 11, the bearing housing 21, and the turbine housing 31 are integrally assembled. Specifically, the compressor housing 11 and the turbine housing 31 are assembled on both sides of the bearing housing 21, respectively. Note that although the bearing housing 21 includes a refrigerant passage 23 through which a refrigerant such as cooling water or antifreeze flows, the turbine housing 31 does not include such a refrigerant passage 23.

A compressor wheel 12 is housed within the compressor housing 11 . The compressor wheel 12 is fixed to one end of the turbine shaft 32 by a nut 13. The compressor wheel 12 rotates together with the turbine shaft 32. The compressor wheel 12 is provided with a plurality of compressor blades. When the compressor wheel 12 rotates, fresh air is accelerated and compressed radially outward by the compressor blades by centrifugal force. Therefore, as shown in FIG. 1, when fresh air is introduced into the center of the compressor housing 11, this fresh air is compressed by the compressor blades of the rotating compressor wheel 12, and this compressed fresh air is It is discharged to the outside of the charger 100. Specifically, this compressed fresh air is discharged toward the engine via the intake pipe. In this way, fresh air flows through the compressor 10.

The bearing housing 21 is provided with various bearings. For example, a thrust bearing for receiving the load in the thrust direction of the turbine shaft 32, a floating bearing for holding the load in the radial direction of the turbine shaft 32, and the like are provided. Bearings are lubricated with oil or the like. The turbine shaft 32 is supported by these various bearings.

A turbine wheel 33 is housed within the turbine housing 31 . The turbine wheel 33 may also be referred to as a turbine impeller. The other end of the turbine shaft 32 is connected to and fixed to the turbine wheel 33 . The turbine wheel 33 is rotationally driven by exhaust gas discharged from the engine. Thereby, the turbine wheel 33 generates rotational power. This rotational power drives the compressor wheel 12 through the turbine shaft 32 to generate compressed fresh air. As mentioned above, compressed fresh air is discharged toward the engine.

Further, a link chamber 50 is formed between the turbine housing 31 and the bearing housing 21. A variable nozzle vane mechanism 34 is arranged in the link chamber 50. As shown in FIG. 2, the variable nozzle vane mechanism 34 includes a ring-shaped first nozzle plate 34a, a plurality of nozzle vanes 34b, a ring-shaped second nozzle plate 34c, and the like. The first nozzle plate 34a is fixed to the bearing housing 21 by being connected to the connecting shaft 22 supported by the bearing housing 21.

The first nozzle plate 34a is arranged at a position facing the shroud portion 31a of the turbine housing 31 so as to be in contact with the turbine housing 31. That is, the first nozzle plate 34a is arranged on the bearing housing 21 side. On the other hand, the second nozzle plate 34c is arranged on the shroud portion 31a of the turbine housing 31. That is, the second nozzle plate 34c is arranged on the turbine housing 31 side. By arranging the first nozzle plate 34a and the second nozzle plate 34c to face each other, a nozzle N through which exhaust gas flows is formed as a flow path.

The nozzle vane 34b is rotatably arranged within the nozzle N with the first nozzle plate 34a supporting one side of the nozzle vane 34b and the second nozzle plate 34c supporting the other side of the nozzle vane 34b. The nozzle vane 34b adjusts the cross section of the flow path in the nozzle N, thereby making the capacity of the turbine 30 variable.

As shown in FIG. 2, the first nozzle plate 34a is integrally provided with a protrusion 34a1 that protrudes from the first nozzle plate 34a toward the second nozzle plate 34c and directly contacts the second nozzle plate 34c. The protrusion 34a1 ensures a gap (hereinafter referred to as nozzle side clearance) between the first nozzle plate 34a and the second nozzle plate 34c. The protrusion 34a1 prevents the nozzle vane 34b from coming into contact with the first nozzle plate 34a and the second nozzle plate 34c. Therefore, the nozzle vane 34b can rotate smoothly. That is, malfunction of the nozzle vane 34b is suppressed.

Further, the contact portion of the protrusion 34a1 with the second nozzle plate 34c, as shown by the arrow It has acceptable sliding properties. This slidability allows the second nozzle plate 34c to contract inward in the radial direction, as shown by arrow X, without being hindered. That is, the slidability allows the second nozzle plate 34c to expand and contract in the radial direction.

In this way, the protrusion 34a1 is not integrally connected to the second nozzle plate 34c and is not restrained, so even if the second nozzle plate 34c expands or contracts in the radial direction, the protrusion 34a1 is not connected to the second nozzle plate 34c. The stress corresponding to the expansion difference between the second nozzle plate 34c and the second nozzle plate 34c does not act on the second nozzle plate 34c via the protrusion 34a1. Therefore, deformation of the contact portion of the second nozzle plate 34c with the protrusion 34a1 can be suppressed, and as a result, deformation of the second nozzle plate 34c can be suppressed.

Furthermore, as shown in FIG. 2, a clearance (hereinafter referred to as turbine side clearance) 36 is provided between the second nozzle plate 34c and the turbine housing 31 to allow expansion of the second nozzle plate 34c. There is. Since the second nozzle plate 34c is often hotter than the turbine housing 31, the second nozzle plate 34c expands. If there is no turbine side clearance 36 and the second nozzle plate 34c expands in the direction along the central axis K of the second nozzle plate 34c (see FIG. 1), the nozzle vane 34b will be compressed by the expanded second nozzle plate 34c. This may hinder smooth rotation. In this embodiment, the presence of the turbine side clearance 36 ensures smooth rotation of the nozzle vane 34b even if the second nozzle plate 34c expands. Note that the center axis K of the second nozzle plate 34c is common to the center axis of the turbine shaft 32.

On the other hand, before the second nozzle plate 34c expands, the positioning of the second nozzle plate 34c may be unstable and vibrate due to the existence of the turbine side clearance 36. When the second nozzle plate 34c vibrates, abnormal noise is generated due to collision between the second nozzle plate 34c and the protrusion 34a1. Further, due to the collision, the contact portion of the protrusion 34a1 with the second nozzle plate 34c may be worn, and the length of the protrusion 34a1 may be shortened. When the length of the protrusion 34a1 becomes short, the nozzle side clearance between the first nozzle plate 34a and the second nozzle plate 34c becomes insufficient, and the nozzle vane 34b is compressed by the expanded second nozzle plate 34c, inhibiting smooth rotation. There is a possibility that

For this reason, as shown in FIG. 2, an expansion space 36a is formed in the turbine side clearance 36 by expanding a part of the turbine side clearance 36, and a C ring 36b as an elastic body is disposed in the expansion space 36a. The C ring 36b urges the inner peripheral portion of the second nozzle plate 34c in the direction toward the bearing housing 21 along the central axis K (see FIG. 1) of the second nozzle plate 34c, as shown by arrow Y. Thereby, the above-mentioned abnormal noise and wear can be suppressed. Further, since the C-ring 36b has elasticity, it can allow the second nozzle plate 34c to expand.

In addition, from the viewpoint of not only suppressing noise and wear but also achieving the above-mentioned sliding properties, it is preferable to arrange the C-ring 36b having an elastic force capable of suppressing noise and wear and achieving sliding properties. desirable. Furthermore, before the second nozzle plate 34c expands, as shown by arrow Z, exhaust gas may flow into the downstream side of the nozzle vane 34b via the turbine side clearance 36. Therefore, it is desirable that the C-ring 36b has a sealing property that prevents exhaust gas from flowing into the downstream side of the nozzle vane 34b. This suppresses the exhaust gas from flowing into the downstream side of the nozzle vane 34b and causes the exhaust gas to flow into the nozzle N, so that a decrease in the turbine efficiency of the turbine 30 can be suppressed. Moreover, the sealing properties of the C-ring 36b suppress the inflow of exhaust gas to the downstream side of the C-ring 36b, and also suppress the rise in temperature of various parts that come into contact with the exhaust flow path. As a result, expansion of various parts that come into contact with the exhaust flow path can be suppressed.

As described above, according to the first embodiment, the turbocharger 100 includes the ring-shaped first nozzle plate 34a, the ring-shaped second nozzle plate, the protrusion 34a1, and the C ring 36b. The first nozzle plate 34a is arranged on the side of the bearing housing 21 through which the refrigerant flows, and supports one side of the nozzle vane 34b. The second nozzle plate 34c is arranged on the side of the turbine housing 31 through which the refrigerant does not flow, and supports the other side of the nozzle vane 34b. The protrusion 34a1 has sliding properties that allow the second nozzle plate 34c to expand and contract in the radial direction, protrudes from the first nozzle plate 34a toward the second nozzle plate 34c, comes into contact with the second nozzle plate 34c, and The nozzle side clearance between the nozzle plate 34a and the second nozzle plate 34c is ensured. The C ring 36b is arranged in the turbine side clearance 36 between the turbine housing 31 and the second nozzle plate 34c, and attaches the second nozzle plate 34c in the direction toward the bearing housing 21 side along the central axis K of the second nozzle plate 34c. to strengthen Thereby, deformation of the second nozzle plate 34c can be suppressed.

(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a partially enlarged view of the vicinity of the nozzle N according to the second embodiment. Components similar to those shown in FIG. 2 are denoted by the same reference numerals, and their explanations will be omitted. The same applies to the third embodiment and subsequent embodiments described below.

In the first embodiment, it has been explained that the first nozzle plate 34a is integrally provided with the protrusion 34a1, but as shown in FIG. 3, the second nozzle plate 34c may be integrally provided with the protrusion 34c1. . In this case, the protrusion 34c1 protrudes from the second nozzle plate 34c toward the first nozzle plate 34a and comes into contact with the first nozzle plate 34a.

In this way, the protrusion 34c1 is not integrally connected to the first nozzle plate 34a and is not constrained, so even if the second nozzle plate 34c expands or contracts in the radial direction, the first nozzle plate 34a and the The stress corresponding to the expansion difference with the second nozzle plate 34c does not act on the first nozzle plate 34a via the projection 34c1. Therefore, deformation of the protrusion 34c1 can be suppressed, and as a result, deformation of the second nozzle plate 34c can be suppressed.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. 4 and 5. FIG. 4 is a partially enlarged view of the vicinity of the nozzle N according to the third embodiment. FIG. 5 is a partially enlarged view of the vicinity of the seal ring 35.

In the first embodiment, it has been explained that the projection 34a1 integrally formed on the first nozzle plate 34a directly contacts the second nozzle plate 34c, but as shown in FIG. 4, a seal ring is attached to the projection 34a1. 35 may be provided so that the protrusion 34a1 indirectly contacts the second nozzle plate 34c via the seal ring 35.

More specifically, as shown in FIG. 5, the central axis K (see FIG. 1) and the central axis (not shown) of the second nozzle plate 34c are common to the end of the protrusion 34a1, and the diameter of the second nozzle plate 34c is A seal ring 35 that is large and whose outer peripheral portion is held by the protrusion 34a1 is arranged. The seal ring 35 has sliding properties similar to those described in the first embodiment. On the other hand, an outer circumferential groove 34d along the outer circumference is formed in the outer circumference of the second nozzle plate 34c. The outer circumferential groove 34d has a width greater than the thickness of the seal ring 35. Then, the inner peripheral part of the seal ring 35 is accommodated in the outer peripheral groove 34d, and the second nozzle plate 34c is biased by the C ring 36b as shown by the arrow Y, so that the outer peripheral part of the second nozzle plate 34c is The inner circumferential portion of the seal ring 35 comes into contact with the inner peripheral portion of the seal ring 35. Thereby, the position of the second nozzle plate 34c with respect to the direction of the central axis K of the second nozzle plate 34c is determined.

Further, as shown in FIG. 5, there is a clearance in the radial direction of the second nozzle plate 34c (hereinafter referred to as radial clearance) between the outer circumferential surface of the second nozzle plate 34c excluding the outer circumferential groove 34d and the protrusion 34a1. 34e is formed. Further, a radial clearance 34f is similarly formed between the outer circumferential surface of the second nozzle plate 34c and the seal ring 35 in the outer circumferential groove 34d.

Therefore, when the second nozzle plate 34c expands in the radial direction, the outer circumference of the second nozzle plate 34c and the inner circumference of the seal ring 35 are in contact with each other, as shown by the arrow W. The second nozzle plate 34c expands while its outer circumference slides (that is, slides) on the inner circumference of the seal ring 35. In particular, an expansion difference occurs between the first nozzle plate 34a and the second nozzle plate 34c due to the heat of exhaust gas, but due to the presence of the radial clearances 34e and 34f, they are formed integrally with the first nozzle plate 34a. The projection 34a1 and the second nozzle plate 34c expand while maintaining non-contact without directly interfering with each other. Therefore, stress corresponding to the expansion difference does not act on the second nozzle plate 34c via the projection 34a1. Therefore, deformation of the second nozzle plate 34c can be suppressed.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG. 6. FIG. 6 is a partially enlarged view of the vicinity of the nozzle N according to the fourth embodiment. In the first embodiment, a structure has been described in which the protrusion 34a1 integrally formed on the first nozzle plate 34a does not penetrate through the second nozzle plate 34c, but as shown in FIG. The protrusion 34a1 formed in the second nozzle plate 34c may be passed through the second nozzle plate 34c, and the tip of the protrusion 34a1 may be caulked.

More specifically, the end of the protrusion 34a1 includes a protrusion detail 34a2 that is thinner than the base of the protrusion 34a1. The length of this protruding detail 34a2 is longer than the thickness of the second nozzle plate 34c. On the other hand, the second nozzle plate 34c is provided with a through hole 34g that penetrates in the axial direction of the second nozzle plate 34c. The size of the radial cross section of this through hole 34g is larger than the size of the radial cross section of the protrusion detail 34a2. When the protrusion detail 34a2 is inserted into the through hole 34g and the tip of the protrusion detail 34a2 protrudes from the second nozzle plate 34c, the tip of the protrusion detail 34a2 is caulked in the direction of the root of the protrusion 34a1, and the protrusion caulking portion is formed. 34a3 is formed. Thereby, the first nozzle plate 34a and the second nozzle plate 34c are joined via the protrusion 34a1.

Since the second nozzle plate 34c is biased by the C ring 36b, the second nozzle plate 34c does not contact the protrusion caulking portion 34a3, but contacts the step between the protrusion 34a1 and the protrusion detail 34a2. In this way, the position of the second nozzle plate 34c with respect to the direction of the central axis K of the second nozzle plate 34c is determined. Note that the step between the protrusion 34a1 and the protrusion detail 34a2 has the above-mentioned sliding property. Here, since the second nozzle plate 34c does not contact the protrusion caulking part 34a3, there is a gap between the second nozzle plate 34c and the protrusion caulking part 34a3 along the central axis K (see FIG. 1) of the second nozzle plate 34c. A clearance (hereinafter referred to as axial clearance) 34h is formed in the direction.

Therefore, when the second nozzle plate 34c expands in the radial direction and the axial direction of the central axis K, the second nozzle plate 34c slides on the step while the second nozzle plate 34c is in contact with the step. At the same time, the second nozzle plate 34c expands. In particular, an expansion difference occurs between the first nozzle plate 34a and the second nozzle plate 34c due to the heat of exhaust gas, but the protrusion caulking portion 34a3 and the second nozzle plate 34c interfere with each other due to the existence of the axial clearance 34h. Inflate while maintaining non-contact. Therefore, stress corresponding to the expansion difference does not act on the second nozzle plate 34c via the projection 34a1. Therefore, deformation of the second nozzle plate 34c can be suppressed.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a partially enlarged view of the vicinity of the nozzle N according to the fifth embodiment. In the first embodiment, the C ring 36b is used as an example of the elastic body, but as shown in FIG. 7, a disc spring 37 may be used as the elastic body. In this case, the disc spring 37 is arranged in the turbine side clearance 36.

The disc spring 37 urges the second nozzle plate 34c in the direction toward the bearing housing 21 along the central axis K (see FIG. 1) of the second nozzle plate 34c. The disc spring 37 may bias between the outer circumferential portion and the inner circumferential portion of the second nozzle plate 34c, or may bias the inner circumferential portion of the second nozzle plate 34c as in the first embodiment. Good too. Thereby, as in the first embodiment, deformation of the second nozzle plate 34c can be suppressed, and abnormal noise and wear described in the first embodiment can be suppressed. Since the disc spring 37 has elasticity, it can allow the second nozzle plate 34c to expand.

Furthermore, from the viewpoint of realizing the slidability described in the first embodiment, it is desirable to dispose a disc spring 37 having an elastic force that can suppress noise and wear and realize slidability. As in the first embodiment, it is desirable that the disc spring 37 has a sealing property that prevents exhaust gas from flowing into the downstream side of the nozzle vane 34b.

Note that when the C ring 36b biases the inner peripheral part of the second nozzle plate 34c with strong elastic force, the contact part between the outer peripheral part of the second nozzle plate 34c and the protrusion 34a1 becomes a fulcrum, so that the second nozzle plate There is a possibility that the inner peripheral portion of the nozzle plate 34c may curve toward the first nozzle plate 34a, and the second nozzle plate 34c may be deformed. In order to suppress such deformation, as shown in FIG. 7, it is desirable that the disc spring 37 biases between the outer and inner circumferential portions of the second nozzle plate 34c.

On the other hand, the outer circumferential portion of the second nozzle plate 34c is located near the upstream side of the exhaust gas flowing into the nozzle N, and therefore tends to become hotter than the inner circumferential portion of the second nozzle plate 34c. If the C-ring 36b is placed in a position where it is likely to become hot, the elastic force of the C-ring 36b may be reduced. For this reason, it is desirable that the C-ring 36b be placed near the inner peripheral portion of the second nozzle plate 34c, where the temperature does not easily rise.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a partially enlarged view of the vicinity of the nozzle N according to the sixth embodiment. In the fifth embodiment, the disc spring 37 is used as an example of the elastic body, but as shown in FIG. 8, the gasket 38 may be used as the elastic body. Similar to the fifth embodiment, the gasket 38 is arranged in the turbine side clearance 36. The gasket 38 may be a coating agent such as FIPG (Formed In Place Gasket), or may be a solid gasket such as a rubber gasket.

The gasket 38 urges the second nozzle plate 34c in the direction toward the bearing housing 21 along the central axis K (see FIG. 1) of the second nozzle plate 34c. For the same reason as in the fifth embodiment, the gasket 38 may bias between the outer circumferential portion and the inner circumferential portion of the second nozzle plate 34c, or may bias the inner circumferential portion of the second nozzle plate 34c. It's okay. Thereby, deformation of the second nozzle plate 34c can be suppressed, and the above-mentioned abnormal noise and wear can be suppressed. Since the gasket 38 has elasticity, it can allow the second nozzle plate 34c to expand.

Furthermore, from the viewpoint of achieving the above-mentioned sliding properties, it is desirable to dispose a gasket 38 having an elastic force that can suppress noise and wear and achieve sliding properties. As described above, it is desirable that the gasket 38 has sealing properties that seal the exhaust gas from flowing into the downstream side of the nozzle vane 34b.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention as described in the claims. Changes are possible. For example, the first to sixth embodiments described above may be partially combined as appropriate.

21 Bearing housing 23 Refrigerant path 31 Turbine housing 34a First nozzle plate 34b Nozzle vane 34c Second nozzle plate 34a1, 34c1 Projection 36b C ring 37 Disc spring 38 Gasket 100 Turbocharger

Claims (1)

a ring-shaped first nozzle plate that is disposed on the bearing housing side through which the refrigerant flows and supports one side of the nozzle vane;
a ring-shaped second nozzle plate that is disposed on a side of the turbine housing through which the refrigerant does not flow and supports another side of the nozzle vane;
The second nozzle plate has sliding properties that allow expansion and contraction in the radial direction of the second nozzle plate, protrudes from one of the first nozzle plate and the second nozzle plate in the other direction and comes into contact with the other, and the first nozzle plate a protrusion that secures a first clearance between the plate and the second nozzle plate;
The second nozzle plate is disposed in a second clearance between the turbine housing and the second nozzle plate that allows expansion of the second nozzle plate, and is directed toward the bearing housing along the central axis of the second nozzle plate. an elastic body that urges the second nozzle plate and blocks exhaust gas from flowing into the downstream side of the nozzle vane through the second clearance ;
A supercharger equipped with

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