Supercharger

Abstract

This supercharger is provided with a turbine wheel, a housing that houses the turbine wheel, a nozzle ring that is housed in the housing, a plurality of nozzle blades that are attached to the nozzle ring, and a positioning means that positions the nozzle ring in the circumferential direction with respect to the housing. The positioning means is provided with: a positioning pin provided on one of the housing and the nozzle ring and extending in the axial direction of the nozzle ring; a first engagement part provided on the other of the housing and the nozzle ring and engaged with the positioning pin; a second elastic member that biases the nozzle ring in the circumferential direction with respect to the housing; and a second engagement part that engages with the second elastic member, the second elastic member and the second engagement part being provided to at least one of the housing and the nozzle ring.

Description

Technical Field

[0001] The present disclosure relates to superchargers. Background Art

[0002] For example, Patent Document 1 describes a supercharger. The supercharger described in Patent Document 1 includes a turbine runner fixed to a turbine shaft, a turbine housing housing the turbine runner, a bearing housing axially supporting the turbine runner, and a variable nozzle vane mechanism located in a connecting rod chamber between the turbine housing and the bearing housing. The variable nozzle vane mechanism includes an annular first nozzle plate located on the bearing housing side, an annular second nozzle plate located on the turbine housing side, and a plurality of nozzle vanes located between and supported by the first and second nozzle plates. An elastic body is located between the turbine housing and the second nozzle plate, biasing the second nozzle plate toward the bearing housing along the central axis of the second nozzle plate.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-76079

[0004] In the above-mentioned supercharger, the second nozzle plate is axially biased relative to the bearing housing by the elastic body, but no particular consideration is given to the circumferential positioning of the nozzle rings of the first and second nozzle plates relative to the bearing housing.

[0005] To position the nozzle ring circumferentially, for example, a locating pin extending axially along the nozzle ring is used. In this case, a clearance fit between the nozzle ring and the locating pin is required to facilitate supercharger assembly. However, a clearance fit between the nozzle ring and the locating pin causes circumferential vibration of the nozzle ring due to engine vibration, which can easily cause wear on the nozzle ring and the locating pin. Typically, an elastic body is used to apply axial force to the nozzle ring, pressing and securing the nozzle ring against the turbine housing or bearing housing. However, this alone may not be able to withstand engine vibration. Summary of the Invention

[0006] An object of the present disclosure is to provide a supercharger capable of suppressing wear of a nozzle ring and a positioning pin.

[0007] A supercharger according to one embodiment of the present disclosure includes: a turbine wheel fixed to a shaft; a housing that houses the turbine wheel and the shaft and rotatably supports the shaft; a nozzle ring housed in the housing and disposed radially outward of the turbine wheel; a plurality of nozzle vanes attached to the nozzle ring so as to be arranged circumferentially of the nozzle ring; a first elastic member that axially biases the nozzle ring relative to the housing; and a positioning unit that circumferentially positions the nozzle ring relative to the housing. The positioning unit includes: a positioning pin provided on one of the housing and the nozzle ring and extending axially of the nozzle ring; a first engaging portion provided on the other of the housing and the nozzle ring and engaging with the positioning pin; a second elastic member that biases the nozzle ring so as to circumferentially constrain the nozzle ring relative to the housing; and a second engaging portion that engages with the second elastic member. The second elastic member and the second engaging portion are provided on at least one of the housing and the nozzle ring. That is, the second elastic member is provided on the housing or the nozzle ring, and the second engaging portion is provided on the housing or the nozzle ring. For example, the second elastic member and the second engaging portion may be both provided on the housing, or both provided on the nozzle ring. Furthermore, the second elastic member may be provided on the housing, and the second engaging portion may be provided on the nozzle ring, or the second elastic member may be provided on the nozzle ring, and the second engaging portion may be provided on the housing.

[0008] In this supercharger, a positioning pin extending axially along the nozzle ring engages with the first engaging portion, thereby circumferentially positioning the nozzle ring relative to the housing. Furthermore, a second elastic member engages with the second engaging portion of the nozzle ring, applying a force to circumferentially constrain the nozzle ring relative to the housing. Therefore, even if there is a circumferential gap between the positioning pin and the nozzle ring, the second elastic member constrains the nozzle ring circumferentially relative to the housing. As a result, circumferential loosening of the nozzle ring relative to the housing is suppressed, thereby preventing circumferential vibration of the nozzle ring relative to the housing even when subjected to external vibration. This also reduces wear on the nozzle ring and positioning pin.

[0009] Alternatively, the positioning pin may be provided on the housing, and the first engaging portion may be provided on the nozzle ring. In such a configuration, the first engaging portion and the second engaging portion may be formed on the nozzle ring using the same process, thereby facilitating the manufacture of the nozzle ring.

[0010] Alternatively, the housing may include an inner circumferential surface that faces the nozzle ring in the axial direction, and the second elastic member may be mounted on the housing so as to be aligned with the positioning pins in the circumferential direction of the nozzle ring, thereby applying a force to the nozzle ring in a direction intersecting the axial and radial directions. In this configuration, the second elastic member, aligned with the positioning pins in the circumferential direction of the nozzle ring, applies a force to the nozzle ring in a direction intersecting the axial and radial directions. Consequently, the nozzle ring is reliably restrained in the circumferential direction relative to the housing.

[0011] Alternatively, the housing may include an inner circumferential surface that faces the nozzle ring in the axial direction, and the second elastic member may be attached to the inner circumferential surface of the housing to apply force to the nozzle ring in a direction intersecting the axial and radial directions. In this configuration, the second elastic member attached to the inner circumferential surface of the housing applies force to the nozzle ring in a direction intersecting the axial and radial directions. As a result, the nozzle ring is reliably constrained in the circumferential direction relative to the housing.

[0012] Alternatively, the nozzle ring may include an outer circumferential surface that faces the housing in the nozzle ring's radial direction. The second engaging portion is provided on the nozzle ring so as to form an opening in the outer circumferential surface and is a cutout portion having a tapered surface. The second elastic member applies a force radially inwardly toward the nozzle ring against the tapered surface of the cutout portion. In this configuration, when the second elastic member applies a force radially inwardly toward the nozzle ring against the tapered surface of the cutout portion, the combined component of this force biases the nozzle ring in a direction intersecting the axial and radial directions. Thus, with a simple structure, the nozzle ring is circumferentially constrained relative to the housing.

[0013] Alternatively, the nozzle ring may include an outer circumferential surface that faces the housing in the nozzle ring's radial direction. The second engaging portion is provided on the nozzle ring so as to form an opening in the outer circumferential surface and is a cutout portion having two inner side surfaces that face each other in the circumferential direction of the nozzle ring. The second elastic member applies a force to one of the two inner side surfaces. In this configuration, the second elastic member applies a force to one inner side surface of the cutout portion of the nozzle ring, directly applying a force to the nozzle ring in a direction intersecting the axial and radial directions. Thus, with a simple structure, the nozzle ring is constrained in the circumferential direction relative to the housing.

[0014] Alternatively, the nozzle ring may be provided with a common engaging portion constituting both the first and second engaging portions, and the second elastic member may be positioned adjacent to the positioning pin in the common engaging portion in the circumferential direction of the nozzle ring, thereby applying force to the nozzle ring in directions intersecting the axial and radial directions. In this configuration, even without the second elastic member being attached to the housing, the nozzle ring is still biased in directions intersecting the axial and radial directions by the second elastic member. This simplifies the housing structure while constraining the nozzle ring circumferentially relative to the housing.

[0015] In one embodiment of the present disclosure, a supercharger includes: a turbine wheel fixed to a shaft; a housing housing the turbine wheel; a nozzle ring housed in the housing and disposed radially outward of the turbine wheel; a plurality of nozzle vanes attached to the nozzle ring; and a positioning unit for positioning the nozzle ring relative to the housing. The positioning unit includes: a positioning pin provided on at least one of the housing and the nozzle ring and extending in the axial direction of the nozzle ring; a pin engaging portion engaging with the positioning pin to circumferentially position the nozzle ring relative to the housing; and an elastic body for applying a force to constrain the nozzle ring circumferentially relative to the housing.

[0016] The structure may further include an elastic body engaging portion provided on at least one of the housing and the nozzle ring and engaged with the elastic body.

[0017] According to the present disclosure, it is possible to suppress wear of the nozzle ring and the positioning pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional view showing a supercharger according to the first embodiment of the present disclosure.

[0019] Figure 2 It is an exploded perspective view of the variable capacity mechanism.

[0020] Figure 3 It is a top view of the variable capacity mechanism.

[0021] Figure 4 It is a top view (including a partial cross section) showing the positioning unit together with the nozzle ring.

[0022] Figure 5 This is a perspective view of the positioning pin and spring components.

[0023] Figure 6 yes Figure 4 A cross-sectional view of the positioning unit is shown.

[0024] Figure 7 It is a top view (including a partial cross section) showing a positioning unit as a comparative example together with a nozzle ring.

[0025] Figure 8 yes Figure 7 A cross-sectional view of the positioning unit is shown.

[0026] Figure 9 This is a plan view (including a partial cross section) showing a modified example of the positioning unit together with the nozzle ring as a supercharger according to the second embodiment of the present disclosure.

[0027] Figure 10 This is a plan view (including a partial cross section) showing another modified example of the positioning unit together with the nozzle ring as a supercharger according to the third embodiment of the present disclosure.

[0028] Figure 11 This is a plan view (including a partial cross section) showing still another modified example of the positioning unit together with the nozzle ring as a supercharger according to the fourth embodiment of the present disclosure.

[0029] Figure 12 This is a cross-sectional view showing a positioning unit of a supercharger according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and repeated description will be omitted.

[0031] Figure 1 1 is a cross-sectional view showing a supercharger according to a first embodiment of the present disclosure. Figure 1 The supercharger 1 of this embodiment is a variable geometry supercharger and is used in, for example, an engine of a vehicle or a ship.

[0032] The supercharger 1 includes a turbine 2, a compressor 3, and a shaft 4 coupling the turbine 2 and the compressor 3. The turbine 2 includes a turbine wheel 5 and a turbine housing 6. The compressor 3 includes a compressor wheel 7 and a compressor housing 8.

[0033] The turbine impeller 5 is fixed to one end of the shaft 4. The compressor impeller 7 is fixed to the other end of the shaft 4. A bearing housing 10 is disposed between the turbine housing 6 and the compressor housing 8. The bearing housing 10 is fixed to the turbine housing 6 and the compressor housing 8. The bearing housing 10 accommodates the shaft 4 and rotatably supports the shaft 4 via the bearing 9.

[0034] The turbine housing 6 houses the turbine wheel 5. The turbine housing 6 has a vortex flow path 11 and an outflow port 12 communicating with the vortex flow path 11. The vortex flow path 11 is provided around the turbine wheel 5. Exhaust gas from the engine flows into the turbine housing 6 through an inlet (not shown), then flows through the vortex flow path 11 and is guided to the turbine wheel 5, causing the turbine wheel 5 to rotate. The exhaust gas then flows out of the turbine housing 6 through the outflow port 12.

[0035] The compressor housing 8 houses the compressor impeller 7. The compressor housing 8 has an intake port 13 and a vortex flow path 14 connected to the intake port 13. The vortex flow path 14 is provided around the compressor impeller 7. When the turbine impeller 5 rotates, the compressor impeller 7 rotates via the shaft 4. As a result, external air is drawn into the compressor housing 8 through the intake port 13. The drawn-in air passes through the compressor impeller 7 and the vortex flow path 14 and is compressed. The compressed air is discharged from a discharge port (not shown) and supplied to the engine.

[0036] In addition, as Figure 2 As shown, the turbine 2 includes a variable capacity mechanism 20 for adjusting the nozzle opening (capacity). The variable capacity mechanism 20 includes a CC plate (clearance control plate) 21, a nozzle ring 22, a CC pin (clearance control pin) 23, multiple nozzle vanes 24, a drive ring 25, multiple nozzle link plates 26, and a drive link plate 27.

[0037] The CC plate 21 is circular. The central axis of the CC plate 21 coincides with the rotation axis X of the shaft 4. The CC plate 21 is arranged so as to surround the turbine wheel 5 around the rotation axis X. The CC plate 21 is arranged radially outward of the turbine wheel 5. The term "radially outward" refers to a position radially farther from the rotation axis X than a certain reference (e.g., the turbine wheel 5). Furthermore, the term "radially inward" refers to a position radially closer to the rotation axis X than a certain reference.

[0038] The CC plate 21 has a plate main surface 21a that faces the inner wall surface 6a of the turbine housing 6, and a plate back surface 21b that faces the nozzle ring 22. The plate back surface 21b is the surface of the CC plate 21 opposite the plate main surface 21a. The CC plate 21 is provided with plate holes 21h that extend from the plate main surface 21a to the plate back surface 21b. Furthermore, the CC plate 21 is provided with a plurality (e.g., three) of pin holes 29. The pin holes 29 are arranged, for example, at equal intervals along the circumference of the CC plate 21.

[0039] The nozzle ring 22 is in the shape of a circular plate. The central axis of the nozzle ring 22 coincides with the rotation axis X of the shaft 4. The nozzle ring 22 is located closer to the bearing housing 10 than the CC plate 21 in the direction of the rotation axis X (axial direction). The nozzle ring 22 is disposed between the CC plate 21 and the bearing housing 10. The nozzle ring 22 is disposed radially outward of the turbine impeller 5. The nozzle ring 22 is arranged so as to surround the turbine impeller 5 or the shaft 4 around the rotation axis X.

[0040] The nozzle ring 22 includes a cylindrical ring body portion 30 , an outer flange portion 31 extending radially outward from the ring body portion 30 , and an inner flange portion 32 extending radially inward from the ring body portion 30 .

[0041] The ring body 30 has an outer peripheral surface 30c. The ring body 30 is provided with a plurality of nozzle shaft holes 33 and cutouts 34 and 35. The nozzle shaft holes 33 are arranged at equal intervals along the circumference of the ring body 30. The cutouts 34 and 35 will be described in detail later.

[0042] The outer flange portion 31 has an outer peripheral surface 31 c. A plurality of (here, three) pin holes 36 are provided in the outer flange portion 31. The central axis of the pin hole 36 coincides with the central axis of the pin hole 29 of the CC plate 21.

[0043] The nozzle ring 22 has a main ring surface 22a that faces the plate back surface 21b of the CC plate 21, and a back ring surface 22b that faces the bearing housing 10. The back ring surface 22b is the surface of the nozzle ring 22 opposite the main ring surface 22a. The nozzle ring 22 is provided with an annular hole 22h that extends from the main ring surface 22a to the back ring surface 22b. The back ring surface 22b includes a main body back surface 30b, an outer flange back surface 31b, and an inner flange back surface 32b. A portion of the main body back surface 30b faces the nozzle link plate 26. The outer flange back surface 31b faces the drive ring 25.

[0044] The CC pin 23 connects the CC plate 21 and the nozzle ring 22. One end of the CC pin 23 is inserted into the pin hole 29 of the CC plate 21. The other end of the CC pin 23 is inserted into the pin hole 36 of the nozzle ring 22. The CC pin 23 defines the gap between the CC plate 21 and the nozzle ring 22. The CC pin 23 functions as a spacer, forming a gap between the CC plate 21 and the nozzle ring 22 for the nozzle vanes 24 to be arranged.

[0045] A plurality of nozzle vanes 24 are arranged between the CC plate 21 and the nozzle ring 22. The nozzle vanes 24 are arranged, for example, at equal intervals along the circumference of the nozzle ring 22. A nozzle shaft 37 extending toward the nozzle ring 22 is fixed to the nozzle vanes 24. The nozzle shaft 37 is inserted through the nozzle shaft hole 33 of the nozzle ring 22. Furthermore, the tip of the nozzle shaft 37 protrudes from the rear surface 30b of the nozzle ring 22. The diameter of the nozzle shaft 37 is slightly smaller than the diameter of the nozzle shaft hole 33. Therefore, the nozzle shaft 37 is rotatable relative to the nozzle ring 22. The nozzle link plate 26 is fixed to the tip of the nozzle shaft 37.

[0046] The drive ring 25 is arranged on the outer flange back surface 31b of the nozzle ring 22. The drive ring 25 circumferentially surrounds the ring body 30 of the nozzle ring 22. The drive ring 25 is coaxial with the nozzle ring 22 and is rotatable relative to the nozzle ring 22 about the rotation axis X.

[0047] The drive ring 25 has a ring main surface 25a that faces the outer flange back surface 31b of the nozzle ring 22, and a ring back surface 25b that faces the bearing housing 10. The ring back surface 25b is the surface of the drive ring 25 opposite the ring main surface 25a. Multiple nozzle link plates 26 are arranged on the ring back surface 25b. A single drive link plate 27 is also arranged on the ring back surface 25b.

[0048] Also like Figure 3 As shown, the drive ring 25 has a plurality of couplings 38 arranged along the circumferential direction. The coupling 38 is composed of a pair of rising portions 38a that clamp the front end portions of the nozzle link plate 26 and the drive link plate 27. The rising portion 38a protrudes from the back surface 25b of the ring. In addition, Figure 3 It is a plan view of the variable displacement mechanism 20 as viewed from the suction port 13 side of the compressor 3 .

[0049] The nozzle link plates 26 are arranged at equal intervals, for example, along the circumferential direction of the drive ring 25. The number of the nozzle link plates 26 is equal to the number of the nozzle vanes 24. The nozzle link plates 26 are rod-shaped.

[0050] The base end of the nozzle link plate 26 is disposed on the main body back surface 30b of the nozzle ring 22. A nozzle shaft hole 39 is provided at the base end of the nozzle link plate 26. The tip end of the nozzle shaft 37 is inserted into the nozzle shaft hole 39. In this state, the tip end of the nozzle shaft 37 is fixed to the nozzle link plate 26 by, for example, caulking.

[0051] The front end of the nozzle link plate 26 is inserted into a pair of raised portions 38a of the coupling 38. Specifically, the front end of the nozzle link plate 26 is merely positioned between the pair of raised portions 38a and is not fixed to the raised portions 38a. Therefore, the nozzle link plate 26 is not fixed to the drive ring 25.

[0052] The drive link plate 27 is disposed between two nozzle link plates 26 arranged in the circumferential direction. The drive link plate 27 has the same structure as the nozzle link plate 26. The drive link plate 27 is connected to a drive mechanism (not shown).

[0053] In this variable displacement mechanism 20, when the drive ring 25 receives driving force from the drive link plate 27, it rotates about the rotation axis X. Consequently, the tip of the nozzle link plate 26 moves circumferentially as the drive ring 25 rotates. Consequently, the nozzle link plate 26 rotates about the nozzle shaft 37. Rotation of the nozzle link plate 26 rotates the nozzle shaft 37, and thus the nozzle vanes 24. This causes the spacing between adjacent nozzle vanes 24 to change. In other words, the cross-sectional area between adjacent nozzle vanes 24 changes.

[0054] The turbine 2 is provided with a spring member 40 (see FIG. 1 ) for axially biasing the variable displacement mechanism 20 relative to the turbine housing 6. Figure 1 As the spring member 40 , for example, a disc spring, a coil spring, or a ring spring is used. The spring member 40 constitutes a first elastic member that urges the nozzle ring 22 in the axial direction relative to the turbine housing 6 .

[0055] The spring member 40 is disposed in the space between the annular heat shield 41 and the bearing housing 10. The heat shield 41 is disposed radially inward of the nozzle ring 22. The heat shield 41 is pressed against the inner flange portion 32 of the nozzle ring 22 by the spring member 40 and retained. The spring member 40 is disposed between the back surface 41b of the heat shield 41 and the inner wall surface 10a of the bearing housing 10.

[0056] The variable displacement mechanism 20 is positioned and retained by a retaining portion 50 of the bearing housing 10. The retaining portion 50 has a retaining surface 50a that faces the ring back surface 22b of the nozzle ring 22 and the ring back surface 25b of the drive ring 25. The retaining surface 50a is a portion of the inner wall surface 10a of the bearing housing 10. The retaining surface 50a is an example of the inner circumferential surface of the bearing housing 10 and includes a portion that faces the nozzle ring 22 in the axial direction and a portion that faces the nozzle ring 22 in the radial direction.

[0057] like Figure 4 As shown, a positioning pin 51 and a spring member 52 are provided on the retaining portion 50. The positioning pin 51 and the spring member 52 cooperate with the cutouts 34 and 35 provided on the nozzle ring 22 to form a positioning unit 53 (for example, a positioning assembly) for positioning the nozzle ring 22 relative to the bearing housing 10 in the circumferential direction. The positioning unit 53 includes, for example, the positioning pin 51, the spring member 52, and the cutouts 34 and 35. In addition, Figure 4 This is a plan view of the nozzle ring 22 and the positioning unit 53 as viewed from the suction port 13 side of the compressor 3 .

[0058] The positioning pin 51 is arranged at a portion of the holding portion 50 that overlaps with the cutout portion 34. The spring member 52 is arranged at a portion of the holding portion 50 that overlaps with the cutout portion 35. That is, the spring member 52 is mounted on the holding portion 50 so as to be arranged in the circumferential direction of the nozzle ring 22 relative to the positioning pin 51. The positioning pin 51 extends axially toward the nozzle ring 22. Figure 5 As shown in FIG. 5 (a), the positioning pin 51 is cylindrical. The shape of the positioning pin 51 is not particularly limited to a cylindrical shape, and may be a prismatic shape or the like.

[0059] The spring member 52 constitutes a second elastic member that urges the nozzle ring 22 to constrain the bearing housing 10 in the circumferential direction. The spring member 52 is an example of an elastic body. The spring member 52 urges the nozzle ring 22 in a direction intersecting the axial and radial directions. The direction intersecting the axial and radial directions of the nozzle ring 22 is the circumferential direction or tangential direction of the nozzle ring 22. The tangential direction of the nozzle ring 22 is a direction perpendicular to the axial and radial directions of the nozzle ring 22 and is generally the circumferential direction of the nozzle ring 22.

[0060] like Figure 5 As shown in (b), the spring member 52 includes a substantially cylindrical base 54 and a biasing portion 55 integral with the base 54. The base 54 is provided with an axially extending slit 56. The biasing portion 55 extends in a J-shape from a portion of one axial end of the base 54 opposite the slit 56 toward the slit 56. Both the base 54 and the biasing portion 55 are elastically deformable. The spring member 52 is formed, for example, by stamping a thin metal plate into an inverted T-shape and then bending it.

[0061] like Figure 6 As shown, the retaining portion 50 of the bearing housing 10 is provided with mounting holes 57 and 58 having a circular cross section. The mounting holes 57 and 58 are provided so as to form openings in the portion of the retaining surface 50a that faces the nozzle ring 22. The mounting hole 57 has a circular bottom surface 57a and a peripheral surface 57b. The mounting hole 58 has a circular bottom surface 58a and a peripheral surface 58b. Figure 6 A cross section of the nozzle ring 22 along the circumferential direction is shown.

[0062] A portion of the positioning pin 51 is inserted into the mounting hole 57. A portion of the base 54 of the spring member 52 is inserted into the mounting hole 58. Since the base 54 has a slit 56, the base 54 can be inserted into the mounting hole 58 with its shape and diameter aligned with the diameter of the mounting hole 58. The positioning pin 51 is fixed to the holder 50 while inserted into the mounting hole 57. The spring member 52 is fixed to the holder 50 while inserted into the mounting hole 58.

[0063] The cutouts 34 and 35 are provided in the ring body 30 of the nozzle ring 22. The cutouts 34 and 35 are formed so as to form openings in the outer peripheral surface 30c of the ring body 30. The cutouts 34 and 35 are U-shaped when viewed from above. The cutout 34 has two inner side surfaces 34a that face each other in the circumferential direction of the nozzle ring 22, and a curved inner surface 34b that connects these inner side surfaces 34a. The cutout 35 has two inner side surfaces 35a that face each other in the circumferential direction of the nozzle ring 22, and a curved inner surface 35b that connects these inner side surfaces 35a. The cutout 34 constitutes a first engaging portion that engages with the positioning pin 51. The engagement between the positioning pin 51 and the cutout 34 means that their relative movement is restricted by mutual abutment. The cutout 34 is an example of a pin engaging portion. The cutout 35 constitutes a second engaging portion that engages with the spring member 52. The cutout portion 35 is an example of an elastic body engaging portion that engages with the spring member 52 .

[0064] When the variable displacement mechanism 20 is assembled to the holding portion 50 of the bearing housing 10 , the nozzle ring 22 is positioned in the circumferential direction relative to the bearing housing 10 by the positioning means 53 .

[0065] Specifically, if Figure 4 as well as Figure 6 As shown, the tip of the biasing portion 55 of the spring member 52 abuts against one inner side surface 35a of the cutout portion 35. Furthermore, due to the biasing force of the biasing portion 55, the tip of the biasing portion 55 presses against one inner side surface 35a (see arrow P in the figure). This causes the nozzle ring 22 to move slightly in the circumferential direction, and the positioning pin 51 abuts against one inner side surface 34a of the cutout portion 34. This restricts the circumferential movement of the nozzle ring 22 relative to the bearing housing 10.

[0066] exist Figure 6 In the embodiment shown, the positioning pin 51 and the spring member 52 are provided in the bearing housing 10, and the cutouts 34 and 35 are provided in the nozzle ring 22. However, in Figure 6 In the illustrated embodiment, an example may be adopted in which the positioning pin 51 and the cutout portion 35 are provided in the bearing housing 10 , and the cutout portion 34 and the spring member 52 are provided in the nozzle ring 22 .

[0067] Figure 7 FIG is a top view showing a positioning unit 100 as a comparative example together with the nozzle ring 22. Figure 7 In the positioning unit 100 of this comparative example, two positioning pins 51 are attached to the holding portion 50 of the bearing housing 10 , and two notches 34 are provided in the nozzle ring 22 .

[0068] However, in such a positioning unit 100, when an external vibration greater than the frictional holding force of the spring member 40 is applied to the variable displacement mechanism 20 from the engine, the nozzle ring 22 is less likely to withstand the external vibration. Figure 8 As shown, considering the assembly performance of the supercharger 1, a gap S exists along the circumferential direction between the positioning pin 51 and the nozzle ring 22. Therefore, when external vibration is applied to the variable displacement mechanism 20, the nozzle ring 22 vibrates in the circumferential direction, causing the nozzle ring 22 to become loose relative to the bearing housing 10, resulting in wear of the nozzle ring 22 and the positioning pin 51. In addition, Figure 8 A cross section of the nozzle ring 22 along the circumferential direction is shown.

[0069] If the nozzle ring 22 and the positioning pins 51 wear due to circumferential vibration of the nozzle ring 22, the positional relationship of the link system that controls the opening of the nozzle vanes 24 may shift. As a result, the nozzle vanes 24 may open excessively, contacting the turbine wheel 5 and causing damage, or the nozzle vanes 24 may not be maintained at the appropriate opening. This results in reduced durability of the variable displacement mechanism 20 and reduced engine output.

[0070] Therefore, in this embodiment, the positioning pin 51 extending axially along the nozzle ring 22 engages with the notch 34 of the nozzle ring 22, thereby positioning the nozzle ring 22 circumferentially relative to the bearing housing 10. Furthermore, the spring member 52 engages with the notch 35 of the nozzle ring 22, urging the nozzle ring 22 to circumferentially restrain it relative to the bearing housing 10. The engagement of the spring member 52 and the notch 35 restricts relative movement by mutual abutment. Therefore, even if a gap S exists circumferentially between the positioning pin 51 and the nozzle ring 22, the spring member 52 can still restrain the nozzle ring 22 circumferentially relative to the bearing housing 10. As a result, circumferential play of the nozzle ring 22 relative to the bearing housing 10 is suppressed, thereby preventing circumferential vibration of the nozzle ring 22 relative to the bearing housing 10 even when subjected to external vibration. This also reduces wear on the nozzle ring 22 and the positioning pin 51. Consequently, the durability of the variable displacement mechanism 20 is enhanced, improving the commercial quality of the supercharger 1.

[0071] In this embodiment, the positioning pins 51 are provided in the bearing housing 10, and the cutouts 34 are provided in the nozzle ring 22. Therefore, the nozzle ring 22 can be easily manufactured by forming the cutouts 34 and 35 in the nozzle ring 22 in the same process.

[0072] In this embodiment, the nozzle ring 22 is biased in directions intersecting the axial and radial directions by the spring members 52 arranged circumferentially relative to the positioning pins 51. Therefore, the nozzle ring 22 is securely restrained circumferentially relative to the bearing housing 10.

[0073] Furthermore, in this embodiment, a spring member 52 having a base portion 54 and a biasing portion 55 is used. However, the second elastic member is not particularly limited to this, and various modifications are possible. For example, the second elastic member may be a spring member formed by simply winding a thin metal plate.

[0074] Furthermore, in this embodiment, the positioning pin 51 provided on the bearing housing 10 engages with the notch 34 of the nozzle ring 22. However, the first engaging portion that engages with the positioning pin 51 is not particularly limited to the notch 34. For example, the first engaging portion may be an opening (hole) extending from the ring main surface 22a to the ring back surface 22b of the nozzle ring 22, or a depression (recess) provided in the ring back surface 22b of the nozzle ring 22. The second engaging portion that engages with the spring member 52 attached to the bearing housing 10 is also not particularly limited to the notch 35 and may be a hole or a recess.

[0075] Figure 9This is a top view (including a partial cross section) showing a modified example of the positioning unit together with the nozzle ring as a supercharger of the second embodiment of the present disclosure. Figure 4 The corresponding figure.

[0076] exist Figure 9 The turbocharger 1A of this embodiment includes a positioning unit 53A in place of the positioning unit 53 of the first embodiment. The positioning unit 53A includes the positioning pin 51 mounted on the bearing housing 10 and a V-shaped spring member 61 mounted on the turbine housing 6 .

[0077] The spring member 61 is attached to the inner wall portion 60 of the turbine housing 6. The inner wall portion 60 includes an inner circumferential surface 60a that radially opposes the nozzle ring 22. Specifically, the inner circumferential surface 60a opposes the outer circumferential surface 31c of the outer flange portion 31 of the nozzle ring 22. A fixing recess 62 is provided in the inner wall portion 60. The fixing recess 62 is configured to form an opening in the inner circumferential surface 60a. The two ends of the spring member 61 are fixed to the corners of the fixing recess 62. The spring member 61 is attached to the inner circumferential surface 60a of the turbine housing 6 and constitutes a second elastic member that applies force to the nozzle ring 22 in a direction intersecting the axial and radial directions. The spring member 61 is an example of an elastomer.

[0078] The positioning unit 53A also includes the aforementioned cutout 34 provided in the nozzle ring 22, and a V-shaped cutout 63 in a plan view. The cutout 63 is provided in the outer flange 31 of the nozzle ring 22. The cutout 63 is provided so as to form an opening in the outer peripheral surface 31c of the outer flange 31. The cutout 63 is provided at a position circumferentially spaced from the cutout 34 in the nozzle ring 22. The cutout 63 has two tapered surfaces 63a. The tapered surfaces 63a are surfaces that intersect at an angle with respect to the radial direction of the nozzle ring 22. The cutout 63 constitutes a second engaging portion that engages with the spring member 61. The cutout 63 is an example of an elastic engaging portion that engages with the spring member 61.

[0079] The front end (center) of the spring member 61 contacts one tapered surface 63a of the cutout portion 63. The spring member 61 urges the tapered surface 63a of the cutout portion 63 radially inward of the nozzle ring 22 (see arrow A in the figure). At this time, the combined force of the spring member 61 also urges the nozzle ring 22 in the tangential direction (see arrow B in the figure).

[0080] In this embodiment, the nozzle ring 22 is biased in directions intersecting the axial and radial directions by the spring member 61 attached to the inner circumferential surface 60a of the turbine housing 6. Therefore, the nozzle ring 22 is reliably restrained in the circumferential direction relative to the bearing housing 10.

[0081] Furthermore, in this embodiment, when the spring member 61 urges the tapered surface 63a of the notch 63 of the nozzle ring 22 radially inward of the nozzle ring 22, the combined component of this force biases the nozzle ring 22 in a direction intersecting the axial and radial directions. Thus, with a simple structure, the nozzle ring 22 is constrained in the circumferential direction relative to the bearing housing 10.

[0082] In this embodiment, a V-shaped spring member 61 is used. However, the second elastic member that urges the tapered surface 63a of the cutout portion 63 of the nozzle ring 22 radially inward of the nozzle ring 22 is not particularly limited to this, and various modifications are possible. For example, the second elastic member may be a conventional coil spring.

[0083] In the present embodiment, the V-shaped cutout portion 63 having two tapered surfaces 63 a in plan view is provided in the nozzle ring 22 . However, the present invention is not limited to this configuration, and a cutout portion having a single tapered surface may be provided in the nozzle ring 22 .

[0084] In addition, in the present embodiment, the spring component 61 applies force to the conical surface 63a of the cutout portion 63 radially inward of the nozzle ring 22, so that the nozzle ring 22 is applied in a direction intersecting the axial direction and the radial direction. However, the present invention is not particularly limited to this form, and a structure in which a second elastic component directly applies force to the conical surface 63a of the cutout portion 63 in a direction intersecting the axial direction and the radial direction of the nozzle ring 22 may also be adopted.

[0085] In this embodiment, the spring member 61 is attached to the inner circumferential surface 60 a of the turbine housing 6 . However, the present invention is not limited to this embodiment. Depending on the structure of the turbocharger 1A, a second elastic member such as the spring member 61 may be attached to the inner circumferential surface of the bearing housing 10 .

[0086] Figure 10 This is a top view (including a partial cross section) of a supercharger according to a third embodiment of the present disclosure showing another modified example of the positioning unit. Figure 4 The corresponding figure.

[0087] exist Figure 10 The turbocharger 1B of this embodiment includes a positioning unit 53B in place of the positioning unit 53 of the first embodiment. The positioning unit 53B includes the positioning pin 51 mounted on the bearing housing 10 and the spring member 52 mounted on the turbine housing 6.

[0088] The spring member 52 is attached to the inner wall portion 60 of the turbine housing 6. The inner wall portion 60 has an inner circumferential surface 60a that faces the nozzle ring 22 in the radial direction. A mounting hole 65 having a circular cross-section is provided in the inner wall portion 60. The mounting hole 65 is provided so as to open into the inner circumferential surface 60a. The mounting hole 65 has a circular bottom surface 65a and a circumferential surface 65b. The base 54 of the spring member 52 is fixed to the inner wall portion 60 while being inserted into the mounting hole 65. The spring member 52 is attached to the inner circumferential surface 60a of the turbine housing 6 and constitutes a second elastic member that biases the nozzle ring 22 in a direction intersecting the axial and radial directions. The spring member 52 is an example of an elastomer.

[0089] The positioning unit 53B also includes the aforementioned cutout 34 provided in the nozzle ring 22, and a rectangular cutout 66 in a plan view. The cutout 66 is provided in the outer flange 31 of the nozzle ring 22. The cutout 66 is provided so as to form an opening in the outer peripheral surface 31c of the outer flange 31. The outer peripheral surface 31c of the outer flange 31 faces the inner peripheral surface 60a of the inner wall 60. The cutout 66 is provided at a position circumferentially spaced from the cutout 34 in the nozzle ring 22.

[0090] The cutout portion 66 includes two inner side surfaces 66a that face each other in the circumferential direction of the nozzle ring 22, and a planar inner surface 66b that connects these inner side surfaces 66a. The two inner side surfaces 66a are formed, for example, to be parallel. The cutout portion 66 constitutes a second engaging portion that engages with the spring member 52. The cutout portion 66 is an example of an elastic engaging portion that engages with the spring member 52.

[0091] The tip end of the biasing portion 55 of the spring member 52 abuts against one inner side surface 66a of the cutout portion 66. The spring member 52 biases the inner side surface 66a of the cutout portion 66 in a direction intersecting the axial direction and radial direction of the nozzle ring 22 (see arrow Q in the figure). The spring member 52 does not bias the other inner side surface 66a of the cutout portion 66 in a direction intersecting the axial direction and radial direction of the nozzle ring 22.

[0092] In this embodiment, the spring member 52 urges the inner side surface 66a of the notch 66 of the nozzle ring 22, directly biasing the nozzle ring 22 in a direction intersecting the axial and radial directions. Thus, with a simple structure, the nozzle ring 22 is constrained circumferentially relative to the bearing housing 10.

[0093] In the present embodiment, the J-shaped spring member 52 is used. However, the second elastic member for urging only one inner side surface 66 a of the cutout portion 66 of the nozzle ring 22 is not particularly limited thereto, and various modifications are possible.

[0094] In addition, in the present embodiment, a rectangular cutout portion 66 is provided in the nozzle ring 22 when viewed from above. However, as long as there are two inner side surfaces facing each other in the circumferential direction of the nozzle ring 22, the shape of the cutout portion is not particularly limited thereto. It may be U-shaped when viewed from above, similar to the cutout portion 34, or may be trapezoidal in shape when viewed from above.

[0095] In the present embodiment, depending on the structure of the turbocharger 1B, the second elastic member such as the spring member 52 may be attached to the inner peripheral surface of the bearing housing 10 instead of the turbine housing 6 .

[0096] Figure 11 1 is a top view showing another modified example of the positioning unit of the supercharger according to the fourth embodiment of the present disclosure. Figure 4 The corresponding figure.

[0097] exist Figure 11 The supercharger 1C of this embodiment includes a positioning unit 53C in place of the positioning unit 53 of the first embodiment. The positioning unit 53C includes the positioning pin 51 mounted on the bearing housing 10 and a V-shaped spring member 71 provided on the nozzle ring 22. The spring member 71 constitutes a second elastic member that biases the nozzle ring 22 in a direction intersecting the axial and radial directions. The spring member 71 is an example of an elastic body.

[0098] The positioning unit 53C also includes a notch 72, which is generally rectangular in plan view and is provided in the nozzle ring 22. The notch 72 is provided in the ring body 30 so as to open onto the outer peripheral surface 30c of the ring body 30 of the nozzle ring 22. The notch 72 includes two inner side surfaces 72a that face each other in the circumferential direction of the nozzle ring 22, and a generally planar inner surface 72b that connects these inner side surfaces 72a. The notch 72 constitutes a first engaging portion that engages with the positioning pin 51 and a second engaging portion that engages with the spring member 71. In other words, the notch 72 is a common engaging portion that constitutes both the first and second engaging portions. The notch 72 is an example of an elastic engaging portion that engages with the spring member 71.

[0099] The spring member 71 is disposed in the cutout portion 72 together with the positioning pin 51. The spring member 71 is disposed in the cutout portion 72 so as to be circumferentially adjacent to the positioning pin 51. One end of the spring member 71 abuts the positioning pin 51. The other end of the spring member 71 abuts one inner side surface 72a of the cutout portion 72. By applying a force to the one inner side surface 72a of the cutout portion 72, the spring member 71 applies a force to the nozzle ring 22 in a direction intersecting the axial direction and the radial direction (see arrow R in the figure).

[0100] In this embodiment, the spring member 71 is arranged adjacent to the positioning pin 51 in the circumferential direction of the nozzle ring 22 at the notch 72. This allows the spring member 71 to bias the nozzle ring 22 in directions intersecting the axial and radial directions, even without the spring member 71 being attached to the bearing housing 10 or the turbine housing 6. This simplifies the structure of the bearing housing 10 or the turbine housing 6, while still constraining the nozzle ring 22 circumferentially relative to the bearing housing 10.

[0101] In the present embodiment, the V-shaped spring member 71 is used. However, the second elastic member for urging the inner side surface 72 a of the cutout portion 72 of the nozzle ring 22 is not particularly limited thereto, and various modifications are possible.

[0102] In addition, in the present embodiment, a cutout portion 72 is provided in the nozzle ring 22, but the common engaging portion for engaging with the positioning pin 51 and the spring component 71 is not particularly limited to the cutout portion 72, and may be a hole portion passing from the ring main surface 22a of the nozzle ring 22 to the ring back surface 22b, or may be a hole portion (recessed portion) opening on the ring back surface 22b of the nozzle ring 22.

[0103] While some embodiments of the present disclosure have been described above, the present disclosure is not limited to the aforementioned embodiments. For example, in the aforementioned embodiments, a notch that engages with the second elastic member is provided on the nozzle ring 22 as the second engaging portion. However, this is not particularly limiting. For example, a protrusion that engages with the second elastic member may be provided on the nozzle ring 22 as the second engaging portion, or the outer peripheral surface 30c or outer peripheral surface 31c of the nozzle ring 22 may serve as the second engaging portion that engages with the second elastic member.

[0104] In the above embodiment, the nozzle ring 22 is axially biased relative to the turbine housing 6 by the spring member 40. However, the present invention is not limited to this embodiment. Depending on the structure of the supercharger, the nozzle ring 22 may be axially biased relative to the bearing housing 10 by some elastic body.

[0105] In the above embodiment, only one positioning pin 51 is provided in the bearing housing 10 , but the number of positioning pins 51 may be plural. Also, the number of second elastic members may be plural.

[0106] Furthermore, in the above embodiment, the positioning pin 51 is provided on the bearing housing 10, and the first engaging portion that engages with the positioning pin 51 is provided on the nozzle ring 22. However, this is not particularly limited to such a configuration. Alternatively, the positioning pin 51 may be provided on the nozzle ring 22, and the first engaging portion may be provided on the bearing housing 10. In this case, the first engaging portion may be, for example, a hole provided in the retaining portion 50 of the bearing housing 10.

[0107] Figure 12 A supercharger according to a fifth embodiment of the present disclosure is shown in a cross-sectional view of a positioning unit. Figure 6 The corresponding figure.

[0108] exist Figure 12 The supercharger of this embodiment includes a positioning unit 53D in place of the positioning unit 53 of the first embodiment. Positioning unit 53D includes a positioning pin 51D and a spring member 52D. Positioning pin 51D has substantially the same structure as positioning pin 51, and spring member 52D has substantially the same structure as spring member 52. Identical components are denoted by the same reference numerals as those used for positioning pin 51 or spring member 52.

[0109] The nozzle ring 22 is provided with mounting holes 57D and 58D. A portion of the positioning pin 51D is inserted into the mounting hole 57D. A portion of the base 54 of the spring member 52D is inserted into the mounting hole 58D. The positioning pin 51D is fixed to the nozzle ring 22 when inserted into the mounting hole 57D. The spring member 52D is fixed to the nozzle ring 22 when inserted into the mounting hole 58D.

[0110] Notches 34D and 35D are provided in bearing housing 10. Notch 34D constitutes a first engaging portion that engages with positioning pin 51D. Notch 34D is an example of a pin engaging portion. Notch 35D constitutes a second engaging portion that engages with spring member 52. Spring member 52 is an example of an elastic body, and notch 35D is an example of an elastic body engaging portion that engages with spring member 52. Notches 34D and 35D have substantially the same structure as notches 34 and 35, and the same reference numerals as notches 34 and 35 are used to designate these identical structures.

[0111] The positioning pins 51D and the spring members 52D cooperate with the cutouts 34D and 35D provided in the bearing housing 10 to constitute a positioning unit 53D (eg, a positioning assembly) for positioning the nozzle ring 22 in the circumferential direction relative to the bearing housing 10 .

[0112] The spring members 52D are attached to the nozzle ring 22 so as to be arranged side by side with respect to the positioning pins 51D in the circumferential direction of the nozzle ring 22. The positioning pins 51D extend in the axial direction toward the nozzle ring 22.

[0113] The spring member 52D constitutes a second elastic member that urges the nozzle ring 22 to constrain it circumferentially relative to the bearing housing 10. The urging portion 55 of the spring member 52D interferes with the bearing housing 10 to urge the nozzle ring 22, thereby urging the nozzle ring 22 in a direction intersecting the axial and radial directions. The direction intersecting the axial and radial directions of the nozzle ring 22 is the circumferential direction or tangential direction of the nozzle ring 22. The tangential direction of the nozzle ring 22 is a direction perpendicular to the axial and radial directions of the nozzle ring 22 and generally corresponds to the circumferential direction of the nozzle ring 22.

[0114] exist Figure 12 In the embodiment shown, the positioning pin 51D and the spring member 52D are provided in the nozzle ring 22, and the cutout portions 34D and 35D are provided in the bearing housing 10. However, in Figure 12 In the illustrated embodiment, an example may be adopted in which the positioning pin 51D and the cutout portion 35D are provided in the nozzle ring 22 , and the cutout portion 34D and the spring member 52D are provided in the bearing housing 10 .

[0115] Description of Reference Numerals

[0116] 1, 1A, 1B, 1C…supercharger; 4…shaft; 5…turbine impeller; 6…turbine housing (housing); 10…bearing housing (housing); 22…nozzle ring; 24…nozzle vane; 30c…outer peripheral surface; 31c…outer peripheral surface; 34, 34D…cutout (first engaging portion, pin engaging portion); 35, 35D…cutout (second engaging portion, elastic body engaging portion); 40…spring member (first elastic member); 51, 51D…locating pin; 52, 52D…spring member (second elastic member) , elastic body); 53, 53A, 53B, 53C, 53D…positioning unit; 60a…inner circumferential surface; 61…spring component (second elastic component, elastic body); 63…cut-out portion (second engaging portion, elastic body engaging portion); 63a…conical surface; 66…cut-out portion (second engaging portion, elastic body engaging portion); 66a…inner side surface; 71…spring component (second elastic component, elastic body); 72…cut-out portion (first engaging portion, second engaging portion, common engaging portion, pin engaging portion, elastic body engaging portion).

Claims

1. A supercharger, characterized in that: have: a turbine impeller fixed to the shaft; a housing that houses the turbine impeller and the shaft and rotatably supports the shaft; a nozzle ring housed in the housing and disposed radially outside the turbine impeller; a plurality of nozzle vanes mounted on the nozzle ring in a manner arranged along the circumference of the nozzle ring; a first elastic member for applying an axial force to the nozzle ring relative to the housing; as well as a positioning unit for positioning the nozzle ring relative to the housing in a circumferential direction, The positioning unit has: a positioning pin, which is provided on one side of the housing and the nozzle ring and extends along the axial direction of the nozzle ring; a first engaging portion, which is provided on the other of the housing and the nozzle ring and engages with the positioning pin; a second elastic member that applies force in a manner to constrain the nozzle ring in a circumferential direction relative to the housing; as well as A second engaging portion is engaged with the second elastic component, The second elastic member and the second engaging portion are provided on at least one of the housing and the nozzle ring.

2. The supercharger according to claim 1, characterized in that The positioning pin is provided on the housing. The first engaging portion is provided on the nozzle ring.

3. The supercharger according to claim 2, characterized in that The second elastic member is attached to the housing so as to be arranged in a circumferential direction of the nozzle ring relative to the positioning pins, and urges the nozzle ring in a direction intersecting the axial direction and the radial direction.

4. The supercharger according to claim 2, characterized in that The housing includes an inner peripheral surface facing the nozzle ring in the axial direction. The second elastic member is mounted on the inner peripheral surface of the housing and applies a force to the nozzle in a circumferential direction intersecting the axial direction and the radial direction.

5. The supercharger according to claim 4, characterized in that The nozzle ring includes an outer peripheral surface facing the housing in the radial direction of the nozzle ring. The second engaging portion is provided on the nozzle ring so as to form an opening on the outer peripheral surface of the nozzle ring and is a cutout portion having a tapered surface. The second elastic member urges the tapered surface radially inward of the nozzle ring.

6. The supercharger according to claim 4, characterized in that The nozzle ring includes an outer peripheral surface facing the housing in the radial direction of the nozzle ring. The second engaging portion is provided on the nozzle ring so as to form an opening on the outer peripheral surface of the nozzle ring, and is a cutout portion having two inner side surfaces facing each other in the circumferential direction of the nozzle ring. The second elastic member applies force to one of the two inner side surfaces.

7. The supercharger according to claim 2, characterized in that The nozzle ring is provided with a common engaging portion constituting the first engaging portion and the second engaging portion. The second elastic member is disposed adjacent to the positioning pin in the circumferential direction of the nozzle ring in the common engagement portion, and urges the nozzle ring in a direction intersecting the axial direction and the radial direction.

8. A supercharger, characterized in that: have: a turbine impeller fixed to the shaft; a housing accommodating the turbine impeller; a nozzle ring housed in the housing and disposed radially outside the turbine impeller; a plurality of nozzle vanes mounted to the nozzle ring; as well as a positioning unit, which positions the nozzle ring relative to the housing, The positioning unit has: a positioning pin, which is provided on at least one of the housing and the nozzle ring and extends along the axial direction of the nozzle ring; a pin engaging portion, which engages with the positioning pin to position the nozzle ring relative to the housing in the circumferential direction; as well as An elastic body applies a force so as to constrain the nozzle ring in a circumferential direction relative to the housing.

9. The supercharger according to claim 8, characterized in that An elastic body engaging portion is further provided on at least one of the housing and the nozzle ring and is engaged with the elastic body.

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