WO2020021816A1

WO2020021816A1 - Compressor and compression system

Info

Publication number: WO2020021816A1
Application number: PCT/JP2019/018914
Authority: WO
Inventors: 直樹堀川; 能成吉田; 将西岡; 生真西口
Original assignee: 株式会社Ihi
Priority date: 2018-07-24
Filing date: 2019-05-13
Publication date: 2020-01-30
Also published as: JP2020016174A

Abstract

A compressor C comprises a compressor impeller 10 provided with a plurality of blades 10d on an outer periphery of a hub 10a, a compressor housing 4 in which a flow path 11 that houses the compressor impeller is formed, and a protective surface 20a that protrudes radially inward of the compressor impeller from an inner wall surface 4a of the housing facing the flow path, and faces radially outer part of the blades along a direction of a rotational axis of the compressor impeller.

Description

Compressors and compression systems

The present disclosure relates to a compressor and a compression system. This application claims the benefit of priority based on Japanese Patent Application No. 2018-138714 filed on July 24, 2018, the contents of which are incorporated herein by reference.

Patent Document 1 discloses a compressor in which a compressor impeller is housed in a housing. The housing has a main flow passage for accommodating the compressor impeller and a scroll flow passage located radially outside the compressor impeller. The compressor impeller has a plurality of blades provided on the outer periphery of the hub. The leading edge of the blade faces the opening of the main flow path.

JP 2018-84241 A

In the compressor, solids such as ice blocks may enter the main flow path. The solid that has entered the main flow path collides with the leading edge of the blade. The peripheral speed of the blade is higher as it goes radially outward. For this reason, when a solid material collides with the leading edge in the radial direction outside of the blade, the blade is likely to be damaged.

An object of the present disclosure is to provide a compressor and a compression system capable of reducing blade damage.

A compressor according to an aspect of the present disclosure includes a compressor impeller having a plurality of blades provided on an outer periphery of a hub, a housing having a flow passage that houses the compressor impeller, and an inner wall surface of the housing facing the flow passage. And a protection surface protruding radially inward of the compressor impeller and facing a radially outer part of the blades in the direction of the rotation axis of the compressor impeller.

The protective surface may face at least the radially outermost end of the leading edge of the blade in the rotational axis direction.

The protective surface may be positioned in the rotation axis direction between the tip of the hub and the leading edge of the blade.

From the innermost side in the radial direction of the protective surface, a slope is provided extending in a direction away from the blade in the radially outer side, of the leading edge of the blade, the thickness at the intersection with the extension of the slope is Alternatively, the thickness may be 109% or more of the thickness at the outer end.

At least one of the plurality of blades may include a notch extending from a radially outermost end of the leading edge in a direction radially outward and away from the protective surface. Good.

A compressor according to another aspect of the present disclosure includes a housing in which a flow path including an intake port is formed, a compressor impeller housed in the flow path of the housing, and provided with a plurality of blades on an outer periphery of a hub; Is provided on at least any one of the blades, and from the outer end portion having a thickness of 0.5 mm or more, which is located at the outermost position in the radial direction of the flow path among the leading edges facing the intake port, and is located radially outside, A notch extending in a direction away from the mouth.

径 The radial length of the notch may be 2.5 mm or more and 5.0 mm or less.

圧縮 A compression system according to an aspect of the present disclosure includes a pre-stage compression unit, an intercooler connected to the pre-stage compression unit, and a compressor connected to the intercooler.

According to the present disclosure, damage to the blade is reduced.

FIG. 1 is a schematic sectional view of the supercharger according to the first embodiment. FIG. 2 is an enlarged view of a broken line portion in FIG. FIG. 3 is a diagram illustrating a supercharger according to the second embodiment. FIG. 4 is an enlarged view of the blade. FIG. 5 is an enlarged view of a broken line portion in FIG. FIG. 6 is a diagram showing the relationship between the shape of the notch and the compressor performance. FIG. 7 is a diagram illustrating a supercharger according to the third embodiment. FIG. 8 is a diagram illustrating a compression system.

Hereinafter, an embodiment of the present disclosure will be described with reference to the accompanying drawings. The dimensions, materials, other specific numerical values, and the like shown in the embodiments are merely examples for facilitating understanding, and do not limit the present disclosure unless otherwise specified. In the specification and the drawings, elements having substantially the same function and configuration will be denoted by the same reference numerals, without redundant description, and elements not directly related to the present disclosure will be omitted. I do.

FIG. 1 is a schematic sectional view of the supercharger TC of the first embodiment. Hereinafter, the direction of arrow L shown in FIG. 1 will be described as the left side of the supercharger TC. The direction of arrow R shown in FIG. 1 will be described as the right side of the supercharger TC. As shown in FIG. 1, the supercharger TC includes a supercharger main body 1. The supercharger main body 1 includes a bearing housing 2, a turbine housing 3, and a compressor housing 4 (housing). The turbine housing 3 is connected to the left side of the bearing housing 2 by a fastening bolt 5. The compressor housing 4 is connected to the right side of the bearing housing 2 by a fastening bolt 6.

軸受 A bearing hole 2a is formed in the bearing housing 2. The bearing hole 2a penetrates the supercharger TC in the left-right direction. The bearing hole 2 a accommodates a part of the shaft 7. A pair of bearings 8 are housed in the bearing holes 2a. Here, the bearing 8 is configured by, for example, a full floating bearing. The shaft 7 is rotatably supported by a pair of bearings 8. At the left end of the shaft 7, a turbine impeller 9 is provided. The turbine impeller 9 is rotatably accommodated in the turbine housing 3.

コンプレッサ A compressor impeller 10 is provided at the right end of the shaft 7. A channel 11 is formed in the compressor housing 4. The compressor impeller 10 is rotatably accommodated in the flow path 11. The flow path 11 passes through the compressor housing 4 in the left-right direction. The flow path 11 includes an intake port 11a. The intake port 11a is an opening formed in the compressor housing 4. The intake port 11a opens to the right of the supercharger TC. The intake port 11 a is an upstream end in the flow direction of the air in the flow path 11. The intake port 11a is connected to an air cleaner (not shown).

(4) The diffuser channel 12 is formed by the facing surfaces of the bearing housing 2 and the compressor housing 4. The diffuser channel 12 pressurizes air. The diffuser channel 12 is formed in an annular shape. The diffuser flow path 12 communicates with the flow path 11 on the radially inner side. The diffuser channel 12 is continuous with the channel 11 radially outside.

コンプレッサ A compressor scroll flow path 13 is provided in the compressor housing 4. The compressor scroll channel 13 is annular. The compressor scroll passage 13 is located, for example, radially outside the shaft 7 from the diffuser passage 12. The compressor scroll passage 13 communicates with an intake port of an engine (not shown) and the diffuser passage 12.

(4) When the compressor impeller 10 rotates, air is drawn into the compressor housing 4 from the intake port 11a. The intake air is pressurized and accelerated in a process of flowing between the blades of the compressor impeller 10. The pressurized and accelerated air is pressurized in the diffuser channel 12 and the compressor scroll channel 13. The pressurized air is led to the intake port of the engine. That is, the supercharger TC includes the compressor C including the compressor housing 4 and the compressor impeller 10.

吐出 A discharge port 14 is formed in the turbine housing 3. The discharge port 14 opens on the left side of the supercharger TC. The discharge port 14 is connected to an exhaust gas purification device (not shown). The turbine housing 3 is provided with a flow path 15 and a turbine scroll flow path 16. The turbine scroll flow path 16 is provided, for example, radially outside the flow path 15. The turbine scroll channel 16 is annular. The turbine scroll passage 16 communicates with a gas inlet (not shown). Exhaust gas discharged from an exhaust manifold (not shown) of the engine is guided to the gas inlet. The turbine scroll flow path 16 also communicates with the flow path 15. Therefore, the exhaust gas guided from the gas inlet to the turbine scroll flow path 16 is guided to the discharge port 14 via the flow path 15 and the turbine impeller 9. The exhaust gas guided to the discharge port 14 rotates the turbine impeller 9 during the circulation process.

回転 The rotational force of the turbine impeller 9 is transmitted to the compressor impeller 10 via the shaft 7. When the compressor impeller 10 rotates, the air pressure is increased as described above. The air pressurized by the compressor C is guided to the intake port of the engine.

において In the compressor C, air is sucked into the flow passage 11 from the intake port 11a. Depending on the environment in which the compressor C is used, solids such as ice blocks may be contained in the air sucked into the flow path 11. When the solids enter the flow path 11, the compressor impeller 10 may be damaged by collision with the solids. The compressor C of the present embodiment includes a mechanism for reducing damage to the compressor impeller 10 due to collision with a solid matter.

FIG. 2 is an enlarged view of a broken line portion in FIG. The compressor C includes a compressor housing 4 in which a flow path 11 is formed. The channel 11 includes an intake port 11a. The flow path 11 is open to the outside of the compressor housing 4 at the intake port 11a. The channel 11 accommodates the compressor impeller 10. The inside diameter of the flow path 11 on the intake port 11a side of the compressor impeller 10 is substantially constant. However, the inner diameter of the flow path 11 may gradually decrease as the flow path 11 approaches the compressor impeller 10 from the intake port 11a.

The compressor impeller 10 includes a hub 10a. The diameter of the hub 10a gradually increases as the distance from the intake port 11a increases. Hub 10a has a distal end portion 10a ₁ and the enlarged diameter portion 10a _2. Tip 10a ₁ is an outer diameter is constant. The enlarged diameter portion 10a _2, to the distal end portion 10a _1, contiguous to the opposite side of the air inlet 11a. The enlarged diameter portion 10a ₂ has a diameter gradually increasing as away from the distal end portion 10a _1.

挿 In the hub 10a, an insertion hole 10b penetrating in the left-right direction in FIG. 2 is formed. The shaft 7 is inserted into the insertion hole 10b. The tip of the shaft 7 protrudes toward the intake port 11a from the insertion hole 10b. At the tip of the shaft 7, a fastening member 7a is provided. Here, the fastening member 7a is formed of a bolt. The compressor impeller 10 is attached to the shaft 7 by the axial force of a fastening member 7 a provided at the tip of the shaft 7. However, the method of attaching the compressor impeller 10 to the shaft 7 is not limited to bolting. For example, the shaft 7 and the compressor impeller 10 may be welded or attached by an adhesive.

複数 A plurality of short blades 10c and blades 10d are provided on the outer periphery of the hub 10a. The short blades 10c and the blades 10d are alternately arranged on the outer periphery of the hub 10a. The short blades 10c and the blades 10d are provided apart from each other in a rotation direction of the compressor impeller 10 (hereinafter, simply referred to as a rotation direction). The short blades 10c and the blades 10d adjacent to each other in the rotation direction maintain an equal interval in the rotation direction. The number of the blades 10d may be two or more on the outer periphery of the hub 10a, and the number is not limited. Further, the short blade 10c is not essential, and the compressor impeller 10 may be provided with a plurality of blades 10d on the outer periphery of the hub 10a.

Short blade 10c are provided within the enlarged diameter portion 10a _2. Blade 10d is provided over the distal end 10a ₁ of the hub 10a to the enlarged diameter portion 10a _2. The blade 10d is longer in the rotation axis direction than the short blade 10c. The blade 10d has a leading edge LE facing the air inlet 11a. The leading edge LE is a surface of the blade 10d that is located closest to the intake port 11a. Leading edge LE has a channel 11 (the compressor impeller 10) radially (hereinafter, simply referred to as radial direction) of the base end portion LE ₁ located innermost. Proximal portion LE ₁ is a section which is continuous with the outer peripheral surface of the hub 10a (distal end 10a _1). Leading edge LE has a outer end portion LE ₂ positioned closest to the outer side in the radial direction. Outer end LE _2, of the leading edge LE, is the site closest to the inner wall surface 4a of compressor housing 4 facing the flow path 11.

The blade 10d has a shape curved in the rotation direction. The base end portion LE ₁ and the outer end portion LE _2, are located offset in the rotational direction. However, the blade 10d may extend linearly in the radial direction. In addition, the thickness of the blade 10d decreases as the distance from the hub 10a increases. The leading edge LE of the blade 10d is the largest thickness of the base end portion LE _1, the thickness becomes smaller toward the outer edge portion LE _2. However, the thickness of the leading edge LE may be constant. Also, the leading edge LE, the thickness of the base end portion LE ₁ may be smaller than the thickness of the outer end portion LE _2. In the present specification, the thickness of the leading edge LE indicates a length in a width direction orthogonal to the extending direction of the leading edge LE and the rotation axis direction.

When the shaft 7 rotates, the compressor impeller 10 (short blade 10c and blade 10d) rotates in the circumferential direction of the shaft 7. The peripheral speed of the leading edge LE is higher as it goes radially outward. Leading edge LE, the higher circumferential speed is faster near the outer end LE _2. The thickness of the leading edge LE is smaller toward the outside in the radial direction. Assuming that the solids which has entered the flow path 11 collides with the leading edge LE, the more collisions position approaches the outer end LE _2, blade 10d is easily damaged. Accordingly, the compressor C is provided with a protective wall 20 that protects the outer end LE ₂ side of the leading edge LE from the solids.

The protection wall portion 20 is formed of an annular protrusion that protrudes radially inward of the compressor impeller 10 from the inner wall surface 4a of the compressor housing 4 facing the flow path 11. The protection wall portion 20 includes a protection surface 20a that projects substantially perpendicularly from the inner wall surface 4a. That is, the protection surface 20a is a surface parallel to the radial direction. The protection surface 20a protrudes radially inward from the inner wall surface 4a of the compressor housing 4 facing the flow path 11.

リー The leading edge LE of the blade 10d is inclined with respect to the radial direction so that the leading edge LE of the blade 10d is further away from the intake port 11a in the radial direction. The separation distance between the leading edge LE and the protection surface 20a is smaller toward the inside in the radial direction. However, the protection surface 20a may be provided so as to be inclined in a direction closer to the leading edge LE toward the inside in the radial direction. The protection surface 20a may be provided so as to be inclined in a direction away from the leading edge LE toward the inside in the radial direction. The separation distance between the leading edge LE and the protection surface 20a may be larger toward the inside in the radial direction, or may be constant regardless of the position in the radial direction.

The protrusion amount (radial length) of the protection surface 20a is equal to or larger than the radial gap between the compressor impeller 10 and the inner wall surface 4a. The protection surface 20a is opposed to a part of the blade 10d on the outside in the radial direction in the rotation axis direction of the compressor impeller 10. Protected surface 20a, rather than the outer end portions LE ₂ of the leading edge LE, extending to the inside in the radial direction. Protected surface 20a is at least, of the leading edge LE of the blade 10d, facing the rotation axis direction and an outer end portion LE ₂ positioned closest to the outer side in the radial direction. However, the protrusion amount (radial length) of the protection surface 20a is not particularly limited.

(4) The protection surface 20a covers a part of the blade 10d on the radially outer side. Thereby, collision of the solid matter with a part of the blade 10d on the radially outer side is avoided. The risk of damage to the blade 10d is reduced.

Greater distance in the axial direction of the protective surface 20a and the leading edge LE has the possibility of solids collide with the outer end portion LE ₂ is increased. Therefore, it is preferable that the distance between the protection surface 20a and the leading edge LE in the axial direction is small as long as it does not contact each other. The position of the protection wall portion 20 (protection surface 20a) in the rotation axis direction is between the tip of the hub 10a (tip portion 10a ₁ ) and the leading edge LE of the blade 10d. The axial separation distance between the protection surface 20a and the leading edge LE is approximately equal to the radial gap between the blade 10d and the inner wall surface 4a. However, the axial separation distance between the protection surface 20a and the leading edge LE may be larger or smaller than the radial gap between the blade 10d and the inner wall surface 4a.

The protection wall 20 includes an inclined surface 20b. The inclined surface 20b extends from the radially innermost side of the protective surface 20a to the radially outer side and the direction away from the blade 10d (toward the intake port 11a). By the inclined surface 20b, the solid matter that has collided with the protective wall portion 20 is easily guided to the center side of the flow path 11. Solids, easily collides with the proximal end portion LE ₁ side of the leading edge LE.

As an example, the thickness at the outer end LE ₂ of the leading edge LE is assumed to be 0.33 mm. The leading edge LE has a greater thickness as it extends radially inward. When the protruding height (radial length) of the protection surface 20a is 1 mm, the thickness at the intersection x of the leading edge LE of the blade 10d with the extension line of the inclined surface 20b (indicated by a dashed line in FIG. 2). Is 0.36 mm. The intersection x can be said to be the radially outermost position in the range where the solids can collide in the leading edge LE when the inclined surface 20b is provided. When the protection surface 20a is not provided, the minimum thickness of the leading edge LE is 0.33 mm in a range where the solid matter can collide. When the protruding height (the length in the radial direction) of the protection surface 20a is 1 mm, the minimum thickness of the leading edge LE is 0.36 mm in a range where a solid object can collide. Among the leading edge LE of the blade 10d, the thickness at the intersection x of the extension line of the inclined surface 20b is about 9% of the thickness at the outer end portion LE _2.

The greater the projection height of the protected surface 20a (the length in the radial direction), the intersection point x is closer to the base end portion LE _1. The thickness of the leading edge LE is increased closer to the base end portion LE _1. For example, when the protruding height (the length in the radial direction) of the protection surface 20a is 2 mm, the thickness at the intersection x is 0.39 mm. When the protrusion height of the protected surface 20a (the length in the radial direction) is 2 mm, of the leading edge LE of the blade 10d, the thickness at the intersection x of the extension line of the inclined surface 20b is the thickness at the outer end portion LE ₂ It is about 121%. If the thickness increases toward the proximal end portion LE ₁ side of the leading edge LE, the greater the projection height of the protected surface 20a (the length in the radial direction), thickness at the intersection x increases. The projection height of the protective surface 20a, and the thickness of the leading edge LE of the outer end portion LE ₂ and an intersection x is not particularly limited. However, among the leading edge LE of the blade 10d, the thickness at the intersection x of the extension line of the inclined surface 20b may If it is more than 9% of the thickness at the outer end portion LE _2.

As described above, the leading edge LE is slow enough base end portion LE ₁ side peripheral speed. Also, the leading edge LE has a greater thickness as the base end portion LE ₁ side. More collision parts of solids is in the proximal portion LE ₁ side, possibly blade 10d is damaged becomes low. The inclined surface 20b further reduces damage to the blade 10d at the time of collision with a solid object. However, the inclined surface 20b is not essential. For example, the protective wall portion 20 may have a constant inner diameter in the rotation axis direction.

Figure 3 is a diagram for explaining the supercharger TC ₂ of the second embodiment. The supercharger TC2 of the _second embodiment is provided with a notch 30 instead of the protection wall 20 of the supercharger TC of the first embodiment. The configuration other than the protection wall portion 20 and the cutout portion 30 is the same in the first embodiment and the second embodiment. About the same composition as a 1st embodiment, the same numerals are attached as the above and explanation is omitted.

Supercharger TC ₂ of the second embodiment comprises a compressor _{C 2} comprising the compressor housing 4 and the compressor impeller 10A. The flow path 11 including the intake port 11a is formed in the compressor housing 4. The compressor impeller 10 </ b> A is housed in the flow passage 11 of the compressor housing 4. The compressor impeller 10A includes a hub 10a. The diameter of the hub 10a gradually increases as the distance from the intake port 11a increases. Hub 10a includes a tip portion 10a ₁ and the enlarged diameter portion 10a _2. Tip 10a ₁ has an outer diameter approximately constant. The enlarged diameter portion 10a _2, to the distal end portion 10a _1, contiguous to the opposite side of the air inlet 11a. The enlarged diameter portion 10a ₂ has a diameter gradually increasing as away from the distal end portion 10a _1.

The outer periphery of the hub 10a, the short blades 10c and blade 10d ₂ are more respectively provided. Short blade 10c and the vane 10d ₂ are alternately disposed at the outer periphery of the hub 10a. Short blade 10c and the vane 10d _2, the rotation direction of the compressor impeller 10A (hereinafter, simply referred to as rotation direction) is provided spaced apart from one another in. Short blade 10c and the vane 10d adjacent in the rotation direction ₂ is maintained at equal intervals in the rotational direction. Blade 10d ₂ may as long provided two or more on the outer circumference of the hub 10a, the number is not limited. Short blade 10c is not essential, the compressor impeller 10A has only to the plurality of blades 10d ₂ is provided on an outer periphery of the hub 10a.

Short blade 10c are provided within the enlarged diameter portion 10a _2. Blade 10d ₂ are provided across the front end portion 10a ₁ of the hub 10a to the enlarged diameter portion 10a _2. Blade 10d ₂ is longer in the axial direction than the short blades 10c. Blade 10d ₂ is provided with a leading edge LE which faces the air inlet 11a. Leading edge LE, of the blade 10d _2, a surface located on the most air inlet 11a side. Leading edge LE has a passage 11 radial (compressor impeller 10A) (hereinafter, simply referred to as radial direction) proximal end LE ₁ located innermost. Proximal portion LE ₁ is a section which is continuous with the outer peripheral surface of the hub 10a (distal end 10a _1). Leading edge LE has a outer end portion LE ₂ positioned closest to the outer side in the radial direction. Outer end LE _2, of the leading edge LE, is the site closest to the inner wall surface 4a of compressor housing 4 facing the flow path 11.

Figure 4 is an enlarged view of the blade 10d _2. FIG. 4 shows a one vane 10d _2, only a portion in the vicinity of the hub 10a. As shown in FIG. 4, the blade 10d ₂ is a curved shape in the direction of rotation. The base end portion LE ₁ and the outer end portion LE _2, are located offset in the rotational direction. However, the blade 10d ₂ may extend in a straight line in the radial direction. Blade 10d _2, the more away from the hub 10a, the plate thickness is reduced. The leading edge LE of the blade 10d ₂ is the largest thickness of the base end portion LE _1, the thickness becomes smaller toward the outer edge portion LE _2. However, the thickness of the leading edge LE may be constant. Leading edge LE, the thickness of the base end portion LE ₁ may be smaller than the thickness of the outer end portion LE _2.

As shown in FIGS. 3 and 4, the blade 10d ₂ is provided with an edge E that faces the inner wall surface 4a and radially. The outer diameter of the edge E increases as the distance from the inlet 11a increases. Blade 10d ₂ is provided with a cutout portion 30. Cutout portion 30, the outer end portion LE ₂ of the leading edge LE, which extends in a direction away from the inlet port 11a and an outer side in the radial direction. Notches 30 extends from the outer end portion LE ₂ to the edge E.

Here, it is assumed that the notch 30 is not included in the leading edge LE. That is, the cutout portion 30 is provided radially outside the leading edge LE. The notch 30 is further away from the intake port 11a than the leading edge LE. Blade 10d _2, relative to the blade 10d of the first embodiment, differs only in that the cutout portion 30 is provided, other shapes, it is assumed the dimensions are equal. Outer end LE ₂ of the blade 10d _2, rather than the outer end portions LE ₂ of the blade 10d of the first embodiment, by the amount notches 30 are provided, are located inward in the radial direction.

Here, the thickness W of the outer end portion LE ₂ shown in FIG. 4 is 0.5 mm. Blade 10d ₂ is not limited to the leading edge LE, the more outer side in the radial direction, the thickness is reduced. The thickness of the edge E is smaller than the thickness of the outer end portion LE _2. By providing the notch portion 30, the minimum thickness of the leading edge LE is larger than the thickness of the edge E.

FIG. 5 is an enlarged view of a broken line portion in FIG. As shown in FIG. 5, the notch 30 has a 45-degree inclination angle with respect to the rotation axis direction and the radial direction. A front edge portion Ef of the most air inlet 11a side of the edge E, the separation distance L1 in the rotation axis direction of the outer end portion LE ₂ is 2.5 mm. The radial length of the notch 30, that is, the radial distance L ₂ between the front edge Ef of the edge E and the outer end LE ₂ is also 2.5 mm.

Blade 10d ₂ is a curved shape in the direction of rotation. The outer end LE ₂ and the front edge portion Ef, in displaced in the rotational direction position. Here, the separation distance L1, as shown in FIG. 5, the cross-section passing through the rotation axis center of the compressor wheel 10A, before when projected and edge Ef and an outer end LE _2, both the rotation axis direction of the Separation distance. The separation distance L2, of the circle centered on the rotation axis center of the compressor wheel 10A, to the radius of a circle passing through the leading edge Ef, the difference between the radius of a circle passing through the outer end LE _2.

According to the compressor impeller 10A, by notches 30 are provided, the compressor impeller 10 of the first embodiment, the thickness of the outer end portion LE ₂ is increased. If it is ensured a thickness of the outer end portion LE ₂ is more than 0.5 mm, even as a solid to the outer end portion LE ₂ collides, blade 10d ₂ is hardly damaged. By notches 30 are provided, damage of the blades 10d ₂ by collision with solids penetrate between the wing is reduced.

The radial length of the cutout portion 30 (distance L2) is larger, the thickness of the outer end portion LE ₂ is increased. Distance L2 is larger, thereby reducing the risk of blade 10d ₂ can be damaged. However, the larger the distance L2, the area of the blade 10d ₂ is reduced, operation efficiency of the compressor _{C 2} is decreased.

FIG. 6 is a diagram illustrating the relationship between the shape of the notch 30 and the compressor performance. The horizontal axis in FIG. 6 indicates the rotation speed of the compressor impeller 10A. The vertical axis of FIG. 6 indicates the compressor performance of the compressor C2 of the _second embodiment and the compressor of the comparative example. Here, the comparative example differs from the compressor impeller 10A of the second embodiment only in that the notch 30 is not provided, and all other conditions are the same. The solid line in FIG. 6 indicates the compressor performance when the radial length (separation distance L2) of the notch 30 is 2.5 mm (hereinafter, referred to as C2.5). The dashed line in FIG. 6 indicates the compressor performance when the radial length (separation distance L2) of the cutout portion 30 is 5.0 mm (hereinafter, referred to as C5.0).

6 The broken line in FIG. 6 is the compressor performance of the comparative example, and the plot on this broken line indicates that the compressor performance is equal to that of the comparative example. Therefore, in FIG. 6, the lower the distance from the broken line, the greater the decrease in compressor performance with respect to the comparative example. The two-dot chain line in FIG. 6 indicates an allowable line of the compressor performance. Therefore, in FIG. 6, the range between the broken line and the two-dot chain line indicates that the compressor performance is lower than that of the comparative example, but the compressor performance is within an allowable range.

As is clear from FIG. 6, when the cutout portions 30 of C2.5 and C5.0 are provided, the amount of performance decrease with respect to the comparative example is within an allowable range. Although not shown, when the radial length (separation distance L2) of the notch portion 30 exceeds 5.0 mm, the compressor performance falls below the allowable line depending on the number of rotations. Therefore, the radial length (separation distance L2) of the notch 30 is preferably 2.5 mm or more and 5.0 mm or less. In the case the radial length of the notch 30 (distance L2) is 5.0 mm, the thickness of the outer end portion LE ₂ is, for example, 0.65 mm. Therefore, when considering the compressor performance, the outer end portion LE ₂ thickness, 0.5 mm or more and may be less than 0.65 mm. However, if the compressor performance is not taken into consideration, the radial length (separation distance L2) of the notch 30 is not particularly limited.

Figure 7 is a diagram for explaining supercharger TC ₃ of the third embodiment. Turbocharger TC ₃ of the third embodiment, the protective wall portion in the turbocharger TC of the first embodiment 20, and, notches 30 in the supercharger TC ₂ of the second embodiment is provided. The supercharger TC3 of the _third embodiment differs from the first embodiment only in the configuration of the notch 30. The supercharger TC3 of the _third embodiment differs from the second embodiment only in the configuration of the protection wall 20. About the same structure as 1st Embodiment and 2nd Embodiment, the same code | symbol as the above is attached | subjected and description is abbreviate | omitted.

Turbocharger TC ₃ of the third embodiment includes a compressor _{C 3} including the compressor housing 4 and the compressor impeller 10A. A protective wall portion 20 is provided on the inner wall surface 4a of the compressor housing 4. The protection wall portion 20 includes a protection surface 20a protruding inward in the radial direction from the inner wall surface 4a, and an inclined surface 20b extending from the protection surface 20a to the intake port 11a side.

Compressor impeller 10A is provided with a blade 10d _2. Blade 10d ₂ is from the outer end portion LE ₂ of the leading edge LE, includes a cutout portion 30 which extends in the direction away from the inlet port 11a and an outer side in the radial direction. Notches 30 extends from the outer end portion LE ₂ to the edge E. Cutout portion 30, the outer end portion LE ₂ of the leading edge LE, which extends in a direction away from the protective surface 20a and an outer radial. The protection surface 20a faces the notch 30 in the rotation axis direction.

In the compressor C ₃ both the protected surface 20a and the cutout portion 30 is provided, as in the first embodiment and the second embodiment, is a possibility that the blades 10d ₂ is damaged is reduced. By notches 30 are provided, damage of the blades 10d ₂ by collision with solids penetrate between the wing is reduced.

The protruding height of the protection surface 20a is not particularly limited. Of the protective surface 20a, the portion that best located inward in the radial direction, may be located outward in the radial direction from the outer end LE _2. Of the protective surface 20a, the portion that best located inward in the radial direction may be opposite to the outer end portion LE ₂ in the rotation axis direction. Protected surface 20a may protrude to the inside in the radial direction from the outer end portion LE _2.

In the third embodiment, the inclined surface 20b is not essential. If the inclined surface 20b is provided, the intersection x of extension and (7 indicated by a dashed line) the blade 10d ₂ of the inclined surface 20b may be located on the leading edge LE. Intersection x may be located on the cutout portion 30, it may coincide with the outer end LE _2.

In a third embodiment, the thickness of the outer end portion LE ₂ and an intersection x is not particularly limited. Incidentally, as in the first embodiment, of the leading edge LE of the blade 10d _2, the thickness at the intersection x of the extension line of the inclined surface 20b is, even more than 9% of the thickness at the outer end portion LE ₂ Good.

In each of the above embodiments, the case where the compressors C, C ₂ , and C ₃ are provided in the supercharger has been described. However, the compressors C, C ₂ , and C ₃ are applicable not only to the supercharger but also to any other devices. Compressor _C, C 2, _{C 3} may be provided alone. Here, an example of a compression system to which the above-described compressor C is applied will be described.

FIG. 8 is a diagram illustrating the compression system 100. The compression system 100 includes a low-pressure stage compression unit 110 (pre-stage compression unit), a first intercooler 120 (intercooler), a compressor C (C ₂ , C ₃ ), and a second intercooler 130. The low-pressure stage compression section 110 increases the pressure of the intake air. The first intercooler 120 is connected to the low-pressure stage compression unit 110. The air pressurized by the low-pressure stage compression section 110 is guided to the first intercooler 120. The first intercooler 120 cools the air guided from the low-pressure stage compression section 110.

圧縮 The compressor C is connected to the first intercooler 120. The air cooled by the first intercooler 120 is drawn into the flow path 11 from the intake port 11a of the compressor C. In the compressor C, the pressure of the air taken into the flow passage 11 is increased in the diffuser flow passage 12 and the compressor scroll flow passage 13 (see FIG. 1). A second intercooler 130 is connected to the compressor scroll passage 13. The second intercooler 130 cools the air pressurized by the compressor C and discharges the air to the outside.

The compression system 100 is a multistage compression system that compresses (pressurizes) air in multiple stages. In the compression system 100, a first intercooler 120 is provided between the low-pressure stage compression section 110 and the compressor C. The first intercooler 120 may generate condensed water from the compressed air compressed by the low-pressure stage compression section 110. In a cold region or the like, condensed water is cooled between the first intercooler 120 and the compressor C, and may become ice blocks. When ice blocks enter the compressor C, the ice blocks may collide with the compressor impeller 10. However, in the compressor C, a part of the leading edge LE of the blade 10d in the radial direction is partially covered with the protection surface 20a. Therefore, there is a low possibility that the blade 10d is damaged by the collision of the ice blocks.

Here, the case where the compression system 100 includes the compressor C of the first embodiment has been described. However, the compression system 100 may include the compressors C ₂ and C ₃ of the _second and third embodiments.

Here, the compressor C, and C _2, C ₃ has been described when used in a multi-stage compression system. However, even in a compression system having only one compression stage, there is a possibility that an ice block may collide with the leading edge LE. The solids that collide with the leading edge LE are not limited to ice blocks. Additional compressor C, C _2, C ₃ is not limited to a multi-stage compression system, the compression stages may be applied to the compression system of only one stage. Compressor _C, C 2, _{C 3} may be used alone.

Although the embodiments of the present disclosure have been described with reference to the accompanying drawings, it is needless to say that the present disclosure is not limited to such embodiments. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the claims, and those modifications naturally belong to the technical scope of the present disclosure. You.

In the first embodiment, the protective wall portion 20 (protective surface 20a) is provided on the entire circumference of the inner wall surface 4a. However, the protective wall portion 20 (protective surface 20a) may be provided on a part of the inner wall surface 4a in the circumferential direction. A plurality of protective wall portions 20 (protective surfaces 20a) may be provided apart from each other in the circumferential direction of the inner wall surface 4a.

In the second and third embodiments, the cutout portion 30 to all of the plurality of blades 10d ₂ are provided. However, the cutout portion 30, only to be provided on at least one of the plurality of blades 10d _2.

形状 The shapes and dimensions of the protective wall portion 20 and the notch portion 30 in each of the above embodiments are merely examples, and the design can be changed as appropriate.

The present disclosure can be used for a compressor and a compression system.

4: Compressor housing (housing) 4a: Inner wall surface 10: Compressor impeller 10A: Compressor impeller 10a: Hub 10d: Blade 10d ₂ : Blade 11: Flow path 11a: Inlet 20a: Protective surface 20b: Inclined surface 30: Notch 100: compression system 110: low-pressure stage compression part (front compression unit) 120: first intercooler (intercooler) C: compressor C _2: compressor C _3: compressor LE: leading edge LE _1: base end portion LE _2: Outer edge

Claims

A compressor impeller provided with a plurality of blades on the outer periphery of the hub,
A housing in which a flow passage for housing the compressor impeller is formed,
A protection that protrudes radially inward of the compressor impeller from an inner wall surface of the housing facing the flow path, and opposes a part of the blades in the radial direction outside of the blade in the rotation axis direction of the compressor impeller. Face and
A compressor comprising:
2. The compressor according to claim 1, wherein the protection surface faces at least an outer end portion of the leading edge of the blade that is located on the outermost side in the radial direction in the rotation axis direction.
The compressor according to claim 1 or 2, wherein the position of the protection surface in the rotation axis direction is between a tip of the hub and a leading edge of the blade.
From the innermost part of the protection surface in the radial direction, an inclined surface extending in a direction away from the blades and outside the radial direction,
4. The compressor according to claim 2, wherein a thickness of the leading edge of the blade at an intersection with an extension of the inclined surface is 109% or more of a thickness at the outer end portion. 5.
At least one of the plurality of blades has a notch extending from a radially outermost end of the leading edge in a direction outside the radial direction and away from the protective surface. The compressor according to any one of claims 1 to 4, further comprising:
A housing in which a flow path including an intake port is formed,
A compressor impeller housed in the flow path of the housing and provided with a plurality of blades on the outer periphery of the hub;
Provided on at least one of the plurality of blades, from a radially outermost end of the leading edge facing the intake port and having a thickness of 0.5 mm or more located on the radially outermost side of the flow path, A cutout portion that is outside and extends in a direction away from the intake port,
A compressor comprising:
The compressor according to claim 5 or 6, wherein the radial length of the notch is 2.5 mm or more and 5.0 mm or less.
A first-stage compression unit;
An intercooler connected to the pre-compressor,
The compressor connected to the intercooler;
The compression system according to any one of claims 1 to 7, comprising: