JP2023122354A - Seal structure of supercharger - Google Patents

Abstract

To provide a seal structure of a supercharger which can suppress the leakage of a lubricant.SOLUTION: A seal structure of a supercharger comprises: a rotating member including a rotating shaft of the supercharger and a rotating wheel provided at one end side of the rotating shaft; a stationary member including a housing for accommodating the rotating member; a bearing for rotatably supporting the rotating shaft; and a seal member formed between the rotating member and the stationary member, and provided in a seal clearance which makes a first space in which the rotating wheel is accommodated and a second space in which the bearing is accommodated communicate with each other. The stationary member includes a stationary-side internal peripheral face for defining the seal clearance, and a stationary-side end face extending in a radial direction of the rotating shaft from an edge of the second space side at the stationary-side internal peripheral face. The stationary end face includes a slope formed in a range in a prescribed peripheral direction at a lower side lower than an axial line of the rotating shaft, and inclined to the second space side in an axial line direction of the rotating shaft as progressing downward from the edge of the second space side of the stationary internal peripheral face.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a supercharger seal structure.

A turbocharger comprises a rotor (rotating body) including a rotating shaft, a turbine impeller mounted on one side of the rotating shaft, and a compressor impeller mounted on the other side of the rotating shaft, and a turbine impeller and a compressor on the rotating shaft. It includes a bearing that rotatably supports the impeller, and a casing (stationary body) that houses the rotor and the bearing. Since the bearings of the turbocharger support a rotating shaft that rotates at high speed, they are likely to reach high temperatures, and if lubrication is insufficient, there is a risk of seizure. Therefore, the bearings are lubricated and cooled by supplying lubricating oil to the bearings. A turbocharger has a seal ring that seals between the outer surface of a rotating body such as a rotor and the inner surface of a stationary body such as a casing in order to prevent leakage of lubricating oil supplied to the bearings to the compressor side or turbine side. (see, for example, Patent Document 1).

JP 2008-232124 A

In a supercharger having a sealing mechanism with a seal ring, there is a risk of leakage of lubricating oil. Specifically, the lubricating oil accumulates in the space between the outer surface of the rotating body to which the seal ring is attached and the inner surface of the stationary body, and the lubricating oil accumulated in the space moves away from the space with the seal ring interposed therebetween. There is a risk of leakage into the side space.

In view of the circumstances described above, at least one embodiment of the present invention aims to provide a supercharger seal structure capable of suppressing leakage of lubricating oil.

A supercharger seal structure according to at least one embodiment of the present invention includes:
A seal structure for a turbocharger,
a rotating member including at least a rotating shaft of the supercharger and a rotating wheel provided on one end side of the rotating shaft;
a stationary member including at least a housing that accommodates the rotating member;
a bearing that rotatably supports the rotating shaft;
A seal gap formed between the rotating member and the stationary member, the seal gap providing communication between a first space in which the rotating wheel is accommodated and a second space in which the bearing is accommodated. a sealing member;
The rotating member includes at least a rotating-side outer peripheral surface that defines the seal gap,
The stationary member includes a stationary-side inner peripheral surface that defines the seal gap, a stationary-side end surface that extends along the radial direction of the rotating shaft from an edge of the stationary-side inner peripheral surface on the second space side, including
The stationary-side end surface is a slope provided in a predetermined circumferential range below the axis of the rotating shaft, and the stationary-side inner peripheral surface has a slope that rotates downward from the edge of the stationary-side inner peripheral surface on the side of the second space. A slope inclined toward the second space in the axial direction of the shaft is included.

According to at least one embodiment of the present invention, there is provided a supercharger seal structure capable of suppressing leakage of lubricating oil.

1 is a schematic cross-sectional view showing a cross section along an axis of a supercharger having a seal structure for a supercharger according to one embodiment; FIG. 1 is a schematic cross-sectional view showing a cross-section along an axis of a seal structure of a supercharger according to one embodiment; FIG. It is a schematic diagram showing a state where the seal structure of the turbocharger according to one embodiment is viewed from the second space side. FIG. 4 is a schematic view showing the vicinity of the slope in the seal structure of the turbocharger according to one embodiment, viewed from above. 1 is a schematic cross-sectional view showing a cross-section along an axis of a seal structure of a supercharger according to one embodiment; FIG.

Several embodiments of the present invention will now be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention, and are merely illustrative examples. do not have.

(supercharger)
FIG. 1 is a schematic cross-sectional view showing a cross section along the axis of a turbocharger provided with a turbocharger seal structure according to one embodiment. As shown in FIG. 1, the turbocharger 1 includes a rotating shaft 11, a turbine wheel 12A provided on one end side of the rotating shaft 11, a compressor wheel 12B provided on the other end side of the rotating shaft 11, A bearing 13 that rotatably supports the rotating shaft 11 , and a housing 14 that houses the rotating shaft 11 , the turbine wheel 12A, the compressor wheel 12B, and the bearing 13 are provided.

Bearing 13 is supported by housing 14 . Rotating shaft 11 is rotatable about axis LA of rotating shaft 11 by being supported by bearing 13 between turbine wheel 12A and compressor wheel 12B.

Hereinafter, the direction in which the axis LA of the rotating shaft 11 extends is defined as the axial direction of the rotating shaft 11 (supercharger 1), and the direction perpendicular to the axis LA is defined as the radial direction of the rotating shaft 11 (supercharger 1). Define. In the axial direction of the rotating shaft 11 (supercharger 1), the side where the turbine wheel 12A is positioned with respect to the compressor wheel 12B is called the turbine side, and the side where the compressor wheel 12B is positioned with respect to the turbine wheel 12A is called the compressor side. do.

The turbine wheel 12A is configured to rotate by the energy of the exhaust gas discharged from the engine directed to the turbine wheel 12A. The compressor wheel 12B rotates together with the rotating shaft 11 in conjunction with the rotation of the turbine wheel 12A. The supercharger 1 compresses the gas (for example, air) guided to the compressor wheel 12B by the rotation of the compressor wheel 12B, increases the density of the gas, and sends the gas to the destination (for example, the engine). Configured.

(Turbocharger seal structure)
FIG. 2 is a schematic cross-sectional view showing a cross section along the axis of the seal structure of the supercharger according to one embodiment. FIG. 2 shows a region surrounded by a chain double-dashed line in FIG. FIG. 3 is a schematic diagram showing a state of the seal structure of the turbocharger according to one embodiment as viewed from the second space side. FIG. 4 is a schematic view showing the vicinity of the slope in the seal structure of the supercharger according to one embodiment, viewed from above. A supercharger seal structure 2 according to some embodiments is a seal structure for suppressing leakage of lubricating oil in the supercharger 1 provided in the supercharger 1 . The seal structure 2 of the supercharger is formed between a rotating member 3, a stationary member 4 accommodating the rotating member 3, and the rotating member 3 and the stationary member 4, as shown in FIGS. It includes the seal member 5 provided in the seal gap 20 and the bearing 13 described above.

(Rotating member, stationary member)
The rotating member 3 is configured to rotate when the supercharger 1 is driven. The rotating member 3 includes at least a rotating shaft 11 and a rotating wheel 12 provided on one end side of the rotating shaft 11 . The stationary member 4 is configured to remain stationary (not rotate) even if the rotating member 3 rotates when the supercharger 1 is driven. The stationary member 4 includes at least a housing 14 .

The stationary member 4 (housing 14 ) accommodates the rotating member 3 and bearings 13 . Inside the stationary member 4 (housing 14), the aforementioned seal gap 20, a first space 21 in which the rotating wheel 12 is accommodated, and a second space 22 in which the bearing 13 is accommodated are formed. The seal gap 20 is provided between the first space 21 and the second space 22 in the axial direction of the rotating shaft 11 to communicate the first space 21 and the second space 22 .

The rotary member 3 has a rotary-side outer peripheral surface 31 that defines the seal gap 20 . The stationary member 4 has a stationary inner peripheral surface 41 that defines the sealing gap 20 . The stationary-side inner peripheral surface 41 is provided radially outwardly of the rotating shaft 11 relative to the rotating-side outer peripheral surface 31 and faces the rotating-side outer peripheral surface 31 with an annular seal gap 20 therebetween.

As shown in FIG. 2 , the stationary member 4 is a stationary member that extends outward in the radial direction along the radial direction of the rotating shaft 11 from an edge 42 of the stationary side inner peripheral surface 41 on the side of the second space 22 . It has a side end face 43 . As shown in FIG. 2, the rotating member 3 has a rotating side extending inward in the radial direction along the radial direction of the rotating shaft 11 from an edge 32 of the rotating side outer peripheral surface 31 on the second space 22 side. It may have an end surface 33 .

(Seal member)
The seal member 5 is configured to seal between the stationary-side inner peripheral surface 41 and the rotating-side outer peripheral surface 31 . In the illustrated embodiment, the seal member (seal ring) 5 is arranged in a compressed state between the stationary side inner peripheral surface 41 and the rotating side outer peripheral surface 31 as shown in FIG. The outer peripheral surface abuts against the inner peripheral surface 41 and the inner peripheral surface abuts against the rotation-side outer peripheral surface 31 . As shown in FIGS. 1 and 2, at least one of the stationary-side inner peripheral surface 41 and the rotating-side outer peripheral surface 31 has a groove extending in the circumferential direction of the rotary shaft 11 for fitting a portion of the seal member 5 thereon. An annular groove extending therealong may be provided.

(Lubricating oil system)
The turbocharger 1 is configured such that lubricating oil flows into the bearing 13 and the second space 22 in which the bearing 13 is accommodated. In the embodiment shown in FIG. 1 , the housing 14 has a lubricating oil inlet 23 for introducing lubricating oil therein, and a lubricating oil supply path 24 for guiding the lubricating oil from the lubricating oil inlet 23 to the bearing 13 . and a lubricating oil discharge port 25 for discharging the lubricating oil to the outside of the housing 14 . The lubricating oil supply path 24 is a flow path defined by the inner wall surface of the housing 14 and communicating between the lubricating oil inlet 23 and the second space 22 . The lubricating oil discharge port 25 is provided below the second space 22 and communicates with the lower portion of the second space 22 .

The lubricating oil introduced into the housing 14 through the lubricating oil inlet 23 is guided to the bearing 13 through the lubricating oil supply path 24 . Most of the lubricating oil guided to the bearing 13 flows downward in the second space 22 and is discharged to the outside of the housing 14 through the lubricating oil discharge port 25 . A part of the lubricating oil guided to the bearing 13 may flow into the seal gap 20 .

The seal structure 2 of the turbocharger 1 according to some embodiments includes the rotating member 3 described above, the stationary member 4 described above, the bearing 13 described above, and the seal member 5 provided in the seal gap 20 described above. , provided. The stationary member 4 includes the stationary inner peripheral surface 41 described above and the stationary side end surface 43 described above. The stationary side end surface 43 includes a slope 6 provided in a predetermined circumferential range CR below the axis LA of the rotating shaft 11, as shown in FIGS. The slope 6 extends toward the second space 22 in the axial direction of the rotating shaft 11 (the direction in which the axis LA of the rotating shaft 11 extends) as it goes downward from the edge 42 of the stationary-side inner peripheral surface 41 on the second space 22 side. Inclined.

The stationary side end surface 43 further includes a flat surface 43A provided outside the area where the slope 6 is formed, as shown in FIGS. The flat surface 43A extends outward along the radial direction of the rotating shaft 11 from the edge 42 of the stationary inner peripheral surface 41 on the side of the second space 22 . As shown in FIG. 4, of the edge 42 on the second space 22 side of the stationary-side inner peripheral surface 41, the slope side edge 42A (upper end edge of the slope 6) connected to the slope 6 is a flat surface connected to the flat surface 43A. It has a concave curved shape that is recessed toward the first space 21 in the axial direction of the rotating shaft 11 from the side edge 42B (the inner peripheral edge that continues to the stationary side inner peripheral surface 41 of the flat surface 43A). The slope 6 has a lower edge 44 that continues to the flat surface 43A. As shown in FIG. 3 , the lower edge 44 has a downwardly convex curved shape when viewed from the second space 22 side in the axial direction of the rotating shaft 11 .

Lubricating oil that has flowed into the seal gap 20 accumulates below the seal gap 20 . At least part of the lubricating oil accumulated in the lower portion of the seal gap 20 flows down along the slope 6 and is discharged into the second space 22 .

According to the above configuration, lubricating oil can be discharged from the lower portion of the seal gap 20 by the slope 6 provided in the predetermined circumferential range CR below the axis LA of the rotating shaft 11 of the stationary side end face 43, so that the seal Lubricating oil can be prevented from accumulating in the lower portion of the gap 20 . The seal structure 2 of the turbocharger suppresses the accumulation of lubricating oil in the lower portion of the seal gap 20, so that the lubricating oil is pushed closer to the first space 21 (rotating wheel 12) than the seal member 5 provided in the seal gap 20. is located) can be suppressed.

In some embodiments, as shown in FIG. 1, the supercharger seal structure 2A (2) is designed to flow lubricating oil from the second space 22 to the first space 21A (21) in which the turbine wheel 12A is housed. It is intended to suppress the leakage of The rotary wheel 12 of the supercharger seal structure 2A consists of the above-described turbine wheel 12A. As shown in FIG. 1 , the first space 21A and the seal gap 20A (20), which are spaces in which the turbine wheel 12A is accommodated, are located in the axial direction of the rotating shaft 11 relative to the second space 22 in which the bearings 13 are accommodated. It is provided on the turbine side.

The rotation-side outer peripheral surface 31A (31) may be, for example, the outer peripheral surface of a boss protruding from the back surface of the turbine wheel 12A as shown in FIG. The stationary side inner peripheral surface 41A (41) may be an inner wall surface of the housing 14 facing the outer peripheral surface of the boss portion of the turbine wheel 12A across the seal gap 20A.

In some embodiments, as shown in FIG. 1, the supercharger seal structure 2B(2) is designed to flow lubricating oil from the second space 22 to the first space 21B(21) in which the compressor wheel 12B is housed. It is intended to suppress the leakage of The rotary wheel 12 of the seal structure 2B of the supercharger consists of the compressor wheel 12B described above. As shown in FIG. 1, the first space 21B (21) and the seal gap 20B (20), which are spaces in which the compressor wheel 12B is accommodated, are closer to the rotating shaft 11 than the second space 22 in which the bearings 13 are accommodated. It is provided on the compressor side in the axial direction.

The rotation-side outer peripheral surface 31B (31) may be, for example, the outer peripheral surface of an annular sleeve 15 included in the supercharger 1 as shown in FIG. The sleeve 15 is attached to the rotating shaft 11 so as to cover the outer circumference of the rotating shaft 11 between the compressor wheel 12B (rotating wheel 12) and the bearing 13 in the axial direction of the rotating shaft 11 . The rotating member 3 may further include a sleeve 15 . The stationary-side inner peripheral surface 41B (41) may be an inner wall surface of the housing 14 facing the outer peripheral surface of the sleeve 15 across the seal gap 20B. Further, the rotation-side outer peripheral surface 31 may be the outer peripheral surface of the rotating shaft 11 .

The supercharger 1 may include both the supercharger seal structures 2A and 2B. That is, the end surface of the stationary inner peripheral surface 41A connected to the compressor side and the end surface of the stationary inner peripheral surface 41B connected to the turbine side may each be the stationary side end surface 43 including the slope 6 described above.

In some embodiments, the slope 6 described above is formed to include a position P1 vertically below the axis LA of the rotating shaft 11, as shown in FIG. In this case, one end 61 of the slope 6 in the circumferential range CR is provided on one side in the horizontal direction with respect to the axis LA of the rotating shaft 11 . The other end 62 of the slope 6 in the circumferential range CR is provided on the opposite side (the other side) of the one end 61 in the horizontal direction with respect to the axis LA of the rotating shaft 11 .

According to the above configuration, by forming the slope 6 so as to include the position P1 vertically below the axis LA of the rotating shaft 11, the rotation of the seal gap 20, which is the portion where the lubricating oil is accumulated in the seal gap 20, is reduced. The lubricating oil can be discharged directly to the slope 6 from the lower region 20C (see FIG. 3) including the position P1 vertically below the axis LA of the shaft 11 . Therefore, the slope 6 including the vertically downward position P1 can effectively discharge lubricating oil from the bottom of the seal gap 20 to the slope 6 compared to the slope 6 not including the vertically downward position P1.

In some embodiments, the slope 6 described above is inclined along the circumferential direction from both ends 61, 62 in the circumferential range CR toward the vertically downward position P1 described above, as shown in FIG.

According to the above configuration, the slope 6 is provided with an inclination along the circumferential direction from both ends 61 and 62 in the circumferential range CR toward the vertically downward position P1. The lubricating oil can flow toward the vertically downward position P1. As a result, the lubricating oil gathers in the vicinity of the position P1 vertically below the slope 6, and the movement of the lubricating oil along the slope of the slope 6 due to its own weight is promoted. .

In a cross section along the axis of the rotating shaft 11 as shown in FIG. 2, the angle of inclination of the slope 6 with respect to a virtual plane obtained by extending the flat surface 43A is defined as θ. In some embodiments, the slope 6 described above is configured such that the inclination angle θ increases from both ends 61 and 62 in the circumferential range CR toward the vertically downward position P1. In this case, the lubricating oil guided to the slope 6 from the seal gap 20 can flow toward the vertically downward position P1, and the lubricating oil can be collected in the vicinity of the vertically downward position P1 of the slope 6.

A slope length L is defined as the length from the upper edge (slope side edge 42A) to the lower edge 44 of the slope 6 in a cross section along the axis of the rotating shaft 11 as shown in FIG. In some embodiments, the slope 6 described above is configured such that the slope length L increases from both ends 61 and 62 in the circumferential range CR toward the vertically downward position P1. In this case, the lubricating oil guided to the slope 6 from the seal gap 20 can flow toward the vertically downward position P1, and the lubricating oil can be collected in the vicinity of the vertically downward position P1 of the slope 6.

If the circumferential range CR of the slope 6 is made too small, the effect of discharging lubricating oil from the seal gap 20 via the slope 6 will be reduced. Also, if the circumferential range CR of the slope 6 is made too large, a redundant slope 6 will be formed in the circumferential range CR where the lubricating oil falls by gravity without passing through the slope 6 .

The circumferential range CR of the slope 6 described above is preferably set to a range of 60° or more and 120° or less. In this case, by setting the circumferential range CR of the slope 6 to a range of 60° or more and 120° or less, the slope 6 can be used more easily than when the circumferential range CR of the slope 6 is set to less than 60°. The effect of discharging lubricating oil from the sealed gap 20 can be improved. In addition, by setting the circumferential range CR of the slope 6 to a range of 60° or more and 120° or less, the surplus slope 6 is Formation can be suppressed, and the formation work of the slope 6 can be shortened.

More preferably, the circumferential range CR of the slope 6 described above is set to a range of 85° or more and 95° or less. In this case, the circumferential range CR of the slope 6 is set to a range of 85° or more and 95° or less, thereby suppressing a decrease in the effect of discharging the lubricating oil from the seal gap 20 via the slope 6. Formation of redundant slopes 6 can be effectively suppressed.

In some embodiments, as shown in FIG. 2, at a position P1 vertically below the axis LA of the rotating shaft 11, an edge 42 (slope side edge 42A) is positioned closer to the first space 21 than the edge 32 of the rotation-side outer peripheral surface 31 on the second space 22 side.

According to the above configuration, the lubricating oil flowing down along the rotation-side end surface 33 has a shape that makes it difficult for the lubricating oil to enter the seal gap 20. Therefore, the inflow of the lubricating oil into the seal gap 20 can be suppressed. It is possible to suppress the lubricating oil from accumulating in the lower part.

FIG. 5 is a schematic cross-sectional view showing a cross section along the axis of the seal structure of the supercharger according to one embodiment. FIG. 5 shows a region surrounded by a two-dot chain line in FIG. In some embodiments, the stationary end surface 43 described above includes the slope 6 described above and a flat surface 43B provided outside the area where the slope 6 is formed, as shown in FIG. The flat surface 43B continues to the lower edge 44 of the slope 6 and extends outward in the radial direction along the radial direction of the rotating shaft 11 from the edge 42 of the stationary-side inner peripheral surface 41 on the second space 22 side. are doing. Below the axis LA of the rotating shaft 11 , the above-described flat surface 43B is positioned closer to the first space 21 than the edge 32 of the rotating-side outer peripheral surface 31 on the second space 22 side. In this case, the lubricating oil flowing down along the rotation-side end surface 33 has a shape that makes it difficult for the lubricating oil to enter the seal gap 20, so that the inflow of the lubricating oil into the seal gap 20 can be suppressed. It is possible to suppress accumulation of lubricating oil.

As used herein, expressions such as "in a certain direction", "along a certain direction", "parallel", "perpendicular", "central", "concentric" or "coaxial", etc. express relative or absolute arrangements. represents not only such arrangement strictly, but also the state of being relatively displaced with a tolerance or an angle or distance to the extent that the same function can be obtained.
For example, expressions such as "identical", "equal", and "homogeneous", which express that things are in the same state, not only express the state of being strictly equal, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the existing state.
Further, in this specification, expressions representing shapes such as a quadrilateral shape and a cylindrical shape not only represent shapes such as a quadrilateral shape and a cylindrical shape in a geometrically strict sense, but also within the range where the same effect can be obtained. , a shape including an uneven portion, a chamfered portion, and the like.
Moreover, in this specification, the expressions “comprising”, “including”, or “having” one component are not exclusive expressions excluding the presence of other components.

The present disclosure is not limited to the above-described embodiments, and includes modifications of the above-described embodiments and modes in which these modes are combined as appropriate.

The contents described in the several embodiments described above are understood as follows, for example.

1) The turbocharger seal structure (2) according to at least one embodiment of the present disclosure is
A seal structure for a supercharger (1),
a rotating member (3) including at least a rotating shaft (11) of the supercharger (1) and a rotating wheel (12) provided at one end of the rotating shaft (11);
a stationary member (4) comprising at least a housing (14) containing said rotating member (3);
a bearing (13) rotatably supporting the rotating shaft (11);
A sealing gap (20) formed between the rotating member (3) and the stationary member (4), the first space (21) accommodating the rotating wheel (12) and the bearing (13). ) and a seal member (5) provided in the seal gap (20) communicating with the second space (22) in which the
The rotating member (3) includes at least a rotating side outer peripheral surface (31) defining the seal gap (20),
The stationary member (4) has a stationary side inner peripheral surface (41) defining the seal gap (20) and an edge (42) of the stationary side inner peripheral surface (41) on the side of the second space (22). a stationary side end face (43) extending along the radial direction of said rotating shaft (11) from
The stationary side end surface (43) is a slope (6) provided in a predetermined circumferential range (CR) below the axis (LA) of the rotating shaft (11), and the stationary side inner peripheral surface ( 41) includes a slope (6) inclined toward the second space (22) side in the axial direction of the rotating shaft (11) as it goes downward from the edge (42) on the second space (22) side.

According to the above configuration 1), the slope (6) provided in the predetermined circumferential range (CR) below the axis (LA) of the rotating shaft (11) of the stationary side end surface (43) reduces the sealing gap. Since the lubricating oil can be discharged from the lower part of (20), it is possible to prevent the lubricating oil from accumulating in the lower part of the seal gap (20). The seal structure (2) for a supercharger described in 1) above suppresses the accumulation of lubricating oil in the lower portion of the seal gap (20), so that the lubricating oil is provided in the seal gap (20). It is possible to suppress leakage to the first space (21) side (the side where the rotating wheel 12 is located) rather than (5).

2) In some embodiments, the turbocharger seal structure (2) according to 1) above,
The slope (6) is formed to include a position (P1) vertically below the axis (LA) of the rotating shaft (11).

According to the configuration of 2) above, by forming the slope (6) to include the position (P1) vertically below the axis (LA) of the rotating shaft (11), lubrication in the seal gap (20) Lubricating oil is discharged directly to the slope (6) from the lower region including the position (P1) vertically below the axis (LA) of the rotating shaft (11) of the seal gap (20), which is the part where the oil is accumulated. can. For this reason, the slope (6) including the vertically downward position (P1) is more inclined from the bottom of the seal gap (20) to the slope (6) than the slope (6) not including the vertically downward position (P1). Lubricating oil can be effectively discharged to

3) In some embodiments, the supercharger seal structure (2) according to 2) above,
The slope (6) slopes along the circumferential direction from both ends (61, 62) in the circumferential range (CR) toward the vertically downward position (P1).

According to the above configuration 3), the slope (6) is provided with an inclination along the circumferential direction from both ends (61, 62) in the circumferential range (CR) toward the vertically downward position (P1). , the lubricating oil guided to the slope (6) from the seal gap (20) can flow toward the vertically downward position (P1). As a result, the flow of lubricating oil formed on the slope (6) gathers the lubricating oil and promotes the movement of the lubricating oil along the slope of the slope (6) by its own weight. It is possible to improve the discharge efficiency of the lubricating oil.

4) In some embodiments, the supercharger sealing structure (7) according to any one of 1) to 3) above,
A circumferential range (CR) of the slope (6) was set to a range of 60° or more and 120° or less.

If the circumferential range (CR) of the slope (6) is made too small, the effect of discharging lubricating oil from the seal gap (20) through the slope (6) will be reduced. Also, if the circumferential range (CR) of the slope (6) is made too large, the excessive slope (6) is formed in the circumferential range (CR) such that the lubricating oil falls by gravity without passing through the slope (6). will be formed. According to the above configuration 4), by setting the circumferential range (CR) of the slope (6) to a range of 60° or more and 120° or less, the circumferential range (CR) of the slope (6) is set to less than 60°. can improve the effect of discharging lubricating oil from the seal gap (20) through the slope (6), compared with the case of setting . Further, by setting the circumferential range (CR) of the slope (6) to a range of 60° or more and 120° or less, when the circumferential range (CR) of the slope (6) is set to a range of more than 120° In comparison, it is possible to suppress the formation of excess slopes (6) and shorten the formation work of the slopes (6).

5) In some embodiments, the turbocharger seal structure (2) according to 4) above,
A circumferential range (CR) of the slope (6) was set to a range of 85° or more and 95° or less.

According to the above configuration 5), the circumferential range (CR) of the slope (6) is set to a range of 85° or more and 95° or less, so that the seal gap (20) through the slope (6) It is possible to effectively suppress the formation of excess slopes (6) while suppressing a decrease in the lubricating oil discharge effect.

6) In some embodiments, the supercharger seal structure (2) according to any one of 1) to 5) above,
The rotating member (3) has a rotating side end surface ( 33) further comprising
At a position (P1) vertically below the axis (LA) of the rotating shaft (11), the edge (42) of the stationary inner peripheral surface (41) on the second space (22) side is: It is positioned closer to the first space (21) than the edge (32) on the second space (22) side of the rotation-side outer peripheral surface (31).

According to the above configuration 6), at the position (P1) vertically below the axis (LA) of the rotating shaft (11), the second space (22) side edge ( 42 (that is, the upper end edge of the slope 6) is positioned closer to the first space (21) than the edge (32) on the second space (22) side of the rotation-side outer peripheral surface (31). In this case, since the lubricating oil flowing down along the rotation side end face (33) is difficult to enter into the seal gap (20), the inflow of the lubricating oil into the seal gap (20) can be suppressed. It is possible to suppress accumulation of lubricating oil in the lower portion of the seal gap (20).

1 supercharger 2, 2A, 2B seal structure 3 rotating member 4 stationary member 5 sealing member 6 slope 11 rotating shaft 12 rotating wheel 12A turbine wheel 12B compressor wheel 13 bearing 14 housing 15 sleeves 20, 20A, 20B seal gap 20C lower region 21, 21A, 21B First space 22 Second space 23 Lubricating oil introduction port 24 Lubricating oil supply path 25 Lubricating oil discharge port 31, 31A, 31B Rotating side outer peripheral surface 32 Rim 33 Rotating side end surface 41, 41A, 41B Stationary inside Peripheral surface 42 Edge 42A Slope side edge 42B Flat surface side edge Side edge 43 Stationary side end surfaces 43A, 43B Flat surface 44 Bottom edges 61, 62 End CR Circumferential range LA Axis P1 Vertically downward position

Claims (6)

A seal structure for a turbocharger,
a rotating member including at least a rotating shaft of the supercharger and a rotating wheel provided on one end side of the rotating shaft;
a stationary member including at least a housing that accommodates the rotating member;
a bearing that rotatably supports the rotating shaft;
A seal gap formed between the rotating member and the stationary member, the seal gap providing communication between a first space in which the rotating wheel is accommodated and a second space in which the bearing is accommodated. a sealing member;
The rotating member includes at least a rotating-side outer peripheral surface that defines the seal gap,
The stationary member includes a stationary-side inner peripheral surface that defines the seal gap, a stationary-side end surface that extends along the radial direction of the rotating shaft from an edge of the stationary-side inner peripheral surface on the second space side, including
The stationary-side end surface is a slope provided in a predetermined circumferential range below the axis of the rotating shaft, and the stationary-side inner peripheral surface has a slope that rotates downward from the edge of the stationary-side inner peripheral surface on the side of the second space. including a slope inclined toward the second space in the axial direction of the shaft,
The seal structure of the supercharger. The slope is formed to include a position vertically below the axis of the rotating shaft,
The seal structure for a supercharger according to claim 1. The slope slopes along the circumferential direction from both ends of the circumferential range toward the vertically downward position.
The seal structure for a supercharger according to claim 2. The circumferential range of the slope is set to a range of 60 ° or more and 120 ° or less,
The supercharger seal structure according to any one of claims 1 to 3. The circumferential range of the slope is set to a range of 85 ° or more and 95 ° or less,
The sealing structure for a supercharger according to claim 4. The rotating member further includes a rotating-side end surface extending along the radial direction of the rotating shaft from the second space-side edge of the rotating-side outer peripheral surface,
At a position vertically below the axis of the rotating shaft, the edge of the stationary-side inner peripheral surface on the second space side is higher than the edge of the rotating-side outer peripheral surface on the second space side. Located on the 1 space side,
The supercharger seal structure according to any one of claims 1 to 3.

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