Oil guide device and supercharger

Abstract

An oil guide (70) is provided with: a cylindrical section (71); a first guide surface (73) that extends radially outward from the outer peripheral surface of the cylindrical section (71) and is formed in a range of 180 DEG or more in the circumferential direction; two second guide surfaces (75) extending radially outward from the outer peripheral surface, extending in a direction intersecting the outer peripheral surface and the first guide surface (73), and disposed symmetrically with respect to an axis of symmetry (A2) when viewed in the axial direction; and four, in total, two first claw parts (76) extending radially outward from the first guide surface (73), disposed symmetrically with respect to the axis of symmetry (A2) when viewed in the axial direction, and having a central portion in the circumferential direction positioned on the opposite side from the second guide surface (75) with respect to the orthogonal axis (A3), and two second claw parts (77) extending radially outward from the second guide surface (75) and disposed symmetrically with respect to the axis of symmetry (A2) when viewed in the axial direction. The two second claw portions (77) extend radially outward from the first guide surface (73), are disposed symmetrically with respect to the axis of symmetry (A2) when viewed in the axial direction, and have central portions in the circumferential direction located on the second guide surface (75) side with respect to the orthogonal axis (A3).

Description

Technical Field

[0001] This disclosure relates to oil guides and turbochargers. This application claims the benefit of priority based on Japanese Patent Application No. 2023-130279, filed on August 9, 2023, the contents of which are incorporated herein by reference. Background Technology

[0002] In various devices, bearings that support a shaft are used. For example, Patent Document 1 discloses a turbocharger equipped with a bearing that supports a shaft. Lubricating oil is supplied to the bearing used in the turbocharger, etc.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 5807436 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The lubricating oil supplied to the bearing is dispersed from the thrust bearing surface as the shaft rotates. The dispersed lubricating oil is blocked by an oil guide and guided to the drain port of the housing. The oil guide is mounted to the housing, for example, by pressing a claw portion provided on the outer periphery of the oil guide. In the installation of an oil guide using a claw portion, it is desirable to improve the coaxiality of the oil guide.

[0008] The purpose of this disclosure is to provide an oil guide and a booster that can improve the coaxiality of the oil guide.

[0009] Solution for solving the problem

[0010] To address the aforementioned issues, the oil guide disclosed herein comprises: a cylindrical portion; a first guide surface extending radially outward from the outer circumference of the cylindrical portion and forming a range of 180° or more along the circumference of the cylindrical portion; two second guide surfaces extending radially outward from the outer circumference of the cylindrical portion and extending in a direction intersecting the outer circumference of the cylindrical portion and the first guide surface, and connecting to each end of the first guide surface in the circumferential direction, and being symmetrically arranged with respect to an axis of symmetry orthogonal to the central axis of the cylindrical portion when viewed along the axial direction of the cylindrical portion; and four claw portions in total, comprising two first claw portions and two second claw portions, wherein the two first claw portions extend radially outward from the first guide surface and are symmetrically arranged with respect to the axis of symmetry when viewed along the axial direction, and the central portion in the circumferential direction is located on the side opposite to the second guide surface with respect to an orthogonal axis passing through the central axis and orthogonal to the axis of symmetry, and the two second claw portions extend radially outward from the first guide surface and are symmetrically arranged with respect to the axis of symmetry when viewed along the axial direction, and the central portion in the circumferential direction is located on the side of the second guide surface with respect to the orthogonal axis.

[0011] Alternatively, the circumferential angle from the orthogonal axis to the center of the first claw in the circumferential direction may be greater than the circumferential angle from the orthogonal axis to the center of the second claw in the circumferential direction.

[0012] Alternatively, the circumferential length of the first claw may be shorter than the circumferential length of the second claw.

[0013] Alternatively, the oil guide can cover the outer periphery of the oil-blocking component. The circumferential length of the first claw, the circumferential length of the second claw, the circumferential angle from the orthogonal axis to the center of the circumferential direction of the first claw, and the circumferential angle from the orthogonal axis to the center of the circumferential direction of the second claw satisfy the relationship expressed by the following formula (1).

[0014] 0.113×(L1×sinθ1-L2×sinθ2)<2×C···(1)

[0015] Where L1: the circumferential length of the first claw.

[0016] L2: Circumferential length of the second claw

[0017] θ1: The circumferential angle from the orthogonal axis to the central portion of the first claw in the circumferential direction.

[0018] θ2: The circumferential angle from the orthogonal axis to the central portion of the second claw in the circumferential direction.

[0019] C: The gap between the oil guide and the oil baffle.

[0020] To address the aforementioned issues, the turbocharger disclosed herein includes the aforementioned oil guide.

[0021] Invention Effects

[0022] According to this disclosure, the coaxiality of the oil guide can be improved. Attached Figure Description

[0023] Figure 1 This is a schematic cross-sectional view of the turbocharger in this embodiment.

[0024] Figure 2 It was extracted Figure 1 The diagram with a single dotted line.

[0025] Figure 3 This is a front view of the oil guide in this embodiment, viewed from the bearing side.

[0026] Figure 4 This is a diagram illustrating the details of the claw portion in the oil guide of this embodiment. Detailed Implementation

[0027] Hereinafter, one embodiment of the present disclosure will be described with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in the embodiment are merely illustrative for ease of understanding and do not limit the present disclosure unless specifically stated otherwise. Furthermore, in this specification and the accompanying drawings, elements that have substantially the same function or structure are omitted from repeated description by using the same reference numerals, and elements not directly related to the present disclosure are omitted from the illustrations.

[0028] Figure 1 This is a schematic cross-sectional view of the turbocharger TC according to this embodiment. Hereinafter, Figure 1 The arrow L shown indicates the left side of the supercharger TC. Figure 1 The arrow R shown indicates the direction to the right of the supercharger TC. For example... Figure 1 As shown, the turbocharger TC includes a turbocharger body 1. The turbocharger body 1 includes a bearing housing 20. A turbine housing 3 is connected to the left side of the bearing housing 20 via a fastening mechanism 2. A compressor housing 5 is connected to the right side of the bearing housing 20 via fastening bolts 4. The bearing housing 20, turbine housing 3, and compressor housing 5 are integrated into one unit.

[0029] A protrusion 20a is provided on the outer peripheral surface of the bearing housing 20. The protrusion 20a is located near the turbine housing 3. The protrusion 20a protrudes radially from the bearing housing 20. A protrusion 3a is provided on the outer peripheral surface of the turbine housing 3. The protrusion 3a is located near the bearing housing 20. The protrusion 3a protrudes radially from the turbine housing 3. The bearing housing 20 and the turbine housing 3 are mounted by fastening the protrusions 20a and 3a together using a fastening mechanism 2. The fastening mechanism 2 is, for example, a G-coupling that clamps the protrusions 20a and 3a.

[0030] The bearing housing 20 has a bearing wall 21. A bearing hole 21a is formed in the bearing wall 21. The bearing hole 21a extends through the turbocharger TC in the left-right direction. A bearing 30 is disposed in the bearing hole 21a. Figure 1 In this example, a semi-floating bearing is shown as a bearing 30. However, bearing 30 can also be any other type of bearing as long as it has at least a thrust bearing surface. Shaft 6 is rotatably supported by bearing 30. A turbine impeller 7 is assembled at the left end of shaft 6. The turbine impeller 7 is rotatably housed in turbine housing 3. A compressor impeller 8 is assembled at the right end of shaft 6. The compressor impeller 8 is rotatably housed in compressor housing 5. A discharge port 22 is formed at the lower part of bearing housing 20 to discharge lubricating oil that has splashed from bearing 30.

[0031] An intake port 9 is formed on the compressor housing 5. The intake port 9 opens to the right side of the booster TC. The intake port 9 is connected to an air filter (not shown). A diffuser flow path 10 is formed by the opposing surfaces of the bearing housing 20 and the compressor housing 5. The diffuser flow path 10 is formed in an annular shape from the radially inner side of the shaft 6 outward. The diffuser flow path 10 communicates with the intake port 9 via the compressor impeller 8 on the aforementioned radially inner side.

[0032] A compressor scroll flow path 11 is provided in the compressor housing 5. The compressor scroll flow path 11 is annular. The compressor scroll flow path 11 is located, for example, radially outward from the diffuser flow path 10 on the shaft 6. The compressor scroll flow path 11 is connected to the intake port of an engine (not shown). The compressor scroll flow path 11 is also connected to the diffuser flow path 10.

[0033] When the compressor impeller 8 rotates, air is drawn into the compressor housing 5 through the intake port 9. The drawn-in air is pressurized and accelerated as it flows between the blades of the compressor impeller 8. The pressurized and accelerated air is further pressurized in the diffuser flow path 10 and the compressor vortex flow path 11. The pressurized air is then guided to the engine intake port.

[0034] An outlet 12 is formed on the turbine housing 3. The outlet 12 opens to the left side of the turbocharger TC. The outlet 12 is connected to an exhaust gas purification device (not shown). A flow path 13 and a turbine vortex flow path 14 are provided in the turbine housing 3. The turbine vortex flow path 14 is annular. The turbine vortex flow path 14 is located, for example, radially outward of the flow path 13 relative to the turbine impeller 7. The turbine vortex flow path 14 communicates with a gas inlet (not shown). The gas inlet guides the exhaust gas discharged from the exhaust manifold of the engine (not shown). The turbine vortex flow path 14 is also connected to the turbine impeller 7 via the aforementioned flow path 13.

[0035] Exhaust gas, guided from the gas inlet to the turbine vortex flow path 14, is then guided to the outlet 12 via the flow path 13 and the turbine impeller 7. The exhaust gas guided to the outlet 12 causes the turbine impeller 7 to rotate during its flow. The rotational force of the turbine impeller 7 is transmitted to the compressor impeller 8 via the shaft 6. As described above, the air is pressurized by the rotational force of the compressor impeller 8 and guided to the engine's intake port.

[0036] Figure 2 It was extracted Figure 1 The diagram showing the dashed-dot section. (Example) Figure 2As shown, an oil passage 23 is formed in the bearing housing 20. The oil passage 23 extends from the outside of the bearing housing 20 to the bearing bore 21a. Lubricating oil flows into the bearing bore 21a from the oil passage 23. A through hole 32 is formed in the main body 31 of the bearing 30. The through hole 32 extends through the main body 31 along the axial direction of the bearing 30. The central axis of the bearing 30 extends in the left-right direction. A shaft 6 is inserted into the through hole 32. Two radial bearing surfaces 34 and 35 are formed on the inner circumferential surface 33 of the main body 31. The radial bearing surfaces 34 and 35 are separated in the axial direction of the bearing 30.

[0037] An oil hole 36 is formed in the main body portion 31 of the bearing 30. The oil hole 36 extends through the main body portion 31 from the inner peripheral surface 33 to the outer peripheral surface 37. A portion of the lubricating oil supplied to the bearing bore 21a flows into the inner peripheral surface 33 through the oil hole 36. The flowing lubricating oil flows from the oil hole 36 to... Figure 2 The lubricating oil diffuses left and right within the shaft. This diffused lubricating oil is supplied to the gap between the shaft 6 and the radial bearing surfaces 34 and 35. Furthermore, the oil film pressure of the lubricating oil supplied to the gap between the shaft 6 and the radial bearing surfaces 34 and 35 provides shaft support for the shaft 6.

[0038] A through hole 38 is formed in the main body portion 31 of the bearing 30. The through hole 38 extends through the main body portion 31 from the inner peripheral surface 33 to the outer peripheral surface 37. A pin hole 21b is formed in the bearing wall portion 21. The pin hole 21b is formed at a position opposite to the through hole 38. The pin hole 21b penetrates the wall portion forming the bearing hole 21a. The locating pin 50 extends from... Figure 2 The lower side of the locating pin 50 is fitted into the pin hole 21b. The front end of the locating pin 50 is inserted into the through hole 38 of the bearing 30. The locating pin 50 restricts the rotation and axial movement of the bearing 30.

[0039] An oil baffle 60 is mounted on the shaft 6. The oil baffle 60 is positioned relative to the main body 31 at... Figure 2 The right side is the compressor impeller 8 side. The oil-blocking component 60 has a generally cylindrical shape. The inner circumferential surface of the oil-blocking component 60 fits into the outer circumferential surface of the shaft 6. The oil-blocking component 60 causes the lubricating oil flowing along the shaft 6 towards the compressor impeller 8 side to be dispersed radially outward. The oil-blocking component 60 can prevent lubricating oil from leaking towards the compressor impeller 8 side.

[0040] In the oil baffle component 60 Figure 2 On the left side, i.e., the bearing 30 side, a first diameter-enlarging portion 61 is provided, which expands radially outward. The opposing surface 61a, which is the left end face of the first diameter-enlarging portion 61, is axially opposed to the main body 31 of the bearing 30. In the oil baffle member 60... Figure 2 On the right side, i.e., the compressor impeller 8 side, a second expansion section 62 is provided, which expands radially outward. The outer peripheral surface of the second expansion section 62 is covered by the sealing plate 80, which will be described later.

[0041] A large-diameter portion 6a is provided on the shaft 6. The large-diameter portion 6a is located relative to the main body 31 of the bearing 30. Figure 2 The left side is the turbine impeller 7 side. The large-diameter section 6a is axially opposite the main body section 31.

[0042] As described above, the axial movement of the main body 31 of the bearing 30 is restricted by the locating pin 50. The main body 31 is axially held by the oil baffle 60 and the large-diameter portion 6a of the shaft 6. Lubricating oil is supplied to the gaps between the main body 31 and the oil baffle 60, and between the main body 31 and the large-diameter portion 6a, respectively. When the shaft 6 moves axially, the oil baffle 60 or the large-diameter portion 6a is supported by the oil film pressure between it and the main body 31.

[0043] In bearing 30, the two axial end faces of the main body 31 become thrust bearing surfaces 41 and 42. Thrust bearing surfaces 41 and 42 bear thrust loads. The left thrust bearing surface 41 of the thrust bearing surfaces 41 and 42 faces the large diameter portion 6a of the shaft 6. The right thrust bearing surface 42 of the thrust bearing surfaces 41 and 42 faces the oil baffle member 60.

[0044] Damping portions 39 and 40 are formed on the outer peripheral surface of the main body 31 at both ends in the axial direction. The damping portions 39 and 40 suppress the vibration of the shaft 6 by means of the oil film pressure of the lubricating oil supplied to the gap between the bearing bore 21a and the inner peripheral surface of the bearing.

[0045] An oil guide 70 is provided on the right side relative to the thrust bearing surface 42 of the bearing 30. The oil guide 70 has a generally cylindrical shape. The oil guide 70 is coaxially mounted with the bearing 30. The oil guide 70 covers the outer periphery of the oil-blocking member 60. Specifically, the outer periphery of the first enlarged diameter portion 61 of the oil-blocking member 60 is covered by the oil guide 70. The oil-blocking member 60 is rotatable relative to the oil guide 70.

[0046] An oil guide 70 is mounted on a sealing plate 80. The sealing plate 80 seals the space between the outer peripheral surface of the oil-blocking member 60 and the inner wall surface of the bearing housing 20. The sealing plate 80 has a generally annular circular plate shape. The inner peripheral surface of the sealing plate 80 is radially opposed to the outer peripheral surface of the second expanded diameter portion 62 of the oil-blocking member 60. The outer peripheral surface of the sealing plate 80 fits into the inner peripheral surface of the bearing housing 20. A guide vane is provided at the outer periphery of the sealing plate 80. Figure 2 The left side of the bearing 30 is the annular protrusion 81. As described later, the oil guide 70 is mounted on the inner circumferential surface 81a of the annular protrusion 81.

[0047] The sealing plate 80 prevents lubricating oil from leaking from the space inside the bearing housing 20 into the space inside the compressor housing 5. Lubricating oil splashed from the thrust bearing surface 42 of the bearing 30 is blocked by the oil guide 70 and guided to the discharge port 22 at the lower part of the bearing housing 20 (see reference). Figure 1 This allows for more effective suppression of lubricating oil leakage to the compressor impeller 8 side.

[0048] Below, in Figure 2 Based on, refer to Figure 3 and Figure 4 The details of the oil guide 70 are explained below. Figure 3 This is a front view of the oil guide 70 of this embodiment, viewed from the bearing 30 side. Figure 2 and Figure 3 In the diagram, the flow of lubricating oil splashed from the thrust bearing surface 42 of bearing 30 is represented by arrows D1, D2, D3, D4, D5, and D6.

[0049] like Figure 2 and Figure 3 As shown, the oil guide 70 includes a cylindrical portion 71, a flat portion 72, a first guide surface 73, an inclined surface 74, and two second guide surfaces 75, namely a second guide surface 75a and a second guide surface 75b. The oil guide 70 is integrally formed, for example, by stamping. However, the oil guide 70 may also be formed by joining multiple components.

[0050] The cylindrical portion 71 and the bearing 30 are arranged coaxially. Therefore, Figure 3 The central axis A1 of the cylindrical portion 71 shown is substantially coaxial with the central axis of the bearing 30. However, as described later, strictly speaking, the central axis A1 of the cylindrical portion 71 may be offset relative to the central axis of the bearing 30, taking into account the coaxiality of the oil guide 70. The planar portion 72 extends radially inward from the left end of the cylindrical portion 71. The planar portion 72 has an annular flat plate shape. The planar portion 72 covers the outer periphery of the oil baffle member 60. Specifically, the inner periphery of the planar portion 72 covers the outer periphery of the first enlarged diameter portion 61 of the oil baffle member 60.

[0051] Hereinafter, the axial, circumferential, and radial directions of the cylindrical portion 71 will also be referred to simply as axial, circumferential, and radial directions. The axial, circumferential, and radial directions of the cylindrical portion 71 are equivalent to the axial, circumferential, and radial directions of the oil guide 70.

[0052] The first guide surface 73 extends radially outward from the outer peripheral surface 71a of the cylindrical portion 71. Specifically, the first guide surface 73 extends from the outer peripheral surface 71a of the cylindrical portion 71. Figure 2 The first guide surface 73 extends radially outward from the right end of the cylindrical portion 71. It is formed over a range of more than 180° along the circumference of the cylindrical portion 71. The first guide surface 73 extends in an arc shape along the circumference of the cylindrical portion 71. The first guide surface 73 faces... Figure 2 The left side is the bearing 30 side.

[0053] Inclined surface 74 is provided in cylindrical portion 71 Figure 2The lower part of the left end of the cylindrical portion 72. An inclined surface 74 extends downward from the lower part of the planar portion 72. The inclined surface 74 advances radially outward from the cylindrical portion 71. Figure 2 The inclined surface 74 is tilted to the left. That is, the inclined surface 74 tilts away from the first guide surface 73 as it moves radially outward toward the cylindrical portion 71.

[0054] like Figure 2 As indicated by the middle arrow D1, a portion of the lubricating oil that splashes from the thrust bearing surface 42 of the bearing 30 is guided along the outer peripheral surface 71a of the cylindrical portion 71 to the first guide surface 73. (As shown in the image) Figure 3 As indicated by arrow D4, the lubricating oil guided to the first guide surface 73 is guided circumferentially along the first guide surface 73. The flow of lubricating oil along the first guide surface 73 (i.e., the flow indicated by arrow D4) is called internal flow. The direction of the internal flow indicated by arrow D4 is consistent with the direction of rotation of shaft 6. That is, arrow D4 indicates that shaft 6... Figure 3 The internal flow under clockwise rotation.

[0055] like Figure 2 As indicated by the middle arrow D2, a portion of the lubricating oil that splashes from the thrust bearing surface 42 of bearing 30 is conveyed downwards along the inclined surface 74. The lubricating oil conveyed downwards along the inclined surface 74 is guided to the discharge port 22 at the lower part of the bearing housing 20 (see reference). Figure 1 ).

[0056] Here, as Figure 2 As indicated by arrow D3, a portion of the lubricating oil that splashes from the thrust bearing surface 42 of bearing 30 passes through the gap between the oil baffle 60 and the oil guide 70 and is discharged toward the compressor impeller 8. The lubricating oil that passes through the gap between the oil baffle 60 and the oil guide 70 is radially dispersed outward as the oil baffle 60 rotates. This radial dispersion of lubricating oil after passing through the gap between the oil baffle 60 and the oil guide 70 (i.e., the flow indicated by arrow D3) is called outflow.

[0057] Figure 3 The inflow indicated by the middle arrow D4 and Figure 2 The outflow indicated by the middle arrow D3 merges near the lower part of the oil guide 70, potentially causing interference. This interference between the internal and external flows is a major cause of reduced lubricant discharge and deterioration of oil seal performance. In the oil guide 70 of this embodiment, interference between the internal and external flows is suppressed by providing second guide surfaces 75a and 75b.

[0058] like Figure 3As shown, second guide surfaces 75a and 75b extend radially outward from the outer peripheral surface 71a of the cylindrical portion 71. The second guide surfaces 75a and 75b extend in a direction intersecting the outer peripheral surface 71a of the cylindrical portion 71 and the first guide surface 73. The second guide surfaces 75a and 75b connect to the outer peripheral surface 71a of the cylindrical portion 71 and the first guide surface 73. The second guide surface 75a connects to the circumferential end 73a of the first guide surface 73. The second guide surface 75b connects to the circumferential end 73b of the first guide surface 73.

[0059] Second guide surfaces 75a and 75b are formed between the first guide surface 73 and the inclined surface 74. That is, the first guide surface 73 and the inclined surface 74 are interconnected via the second guide surfaces 75a and 75b. The second guide surface 75a extends from the end 73a of the first guide surface 73 to the end of the inclined surface 74. Figure 3 It is formed between the left end of the first guide surface 73 and the inclined surface 74. The second guide surface 75b extends over the end 73b of the first guide surface 73 and the inclined surface 74. Figure 3 It is formed between the right ends of the middle.

[0060] The second guide surfaces 75a and 75b are respectively disposed at different positions around the circumference of the cylindrical portion 71. Specifically, as shown in the figure... Figure 3 As shown, when viewed along the axial direction of the cylindrical portion 71, the second guide surfaces 75a and 75b are symmetrically arranged with respect to the axis of symmetry A2, which is orthogonal to the central axis A1 of the cylindrical portion 71. Figure 3 In this example, the axis of symmetry A2 extends vertically. Therefore, the second guide surfaces 75a and 75b are located on the lower side of the oil guide 70. Specifically, when viewed along the axial direction of the cylindrical portion 71, the second guide surfaces 75a and 75b are located lower than the orthogonal axis A3, which passes through the central axis A1 and is orthogonal to the axis of symmetry A2. The second guide surfaces 75a and 75b are located higher than the inclined surface 74. However, the axis of symmetry A2 may also be inclined relative to the vertical direction.

[0061] exist Figure 3 In the example, the second guide surfaces 75a and 75b extend substantially parallel to the axial direction and radial direction of the cylindrical portion 71. More specifically, the second guide surfaces 75a and 75b are slightly inclined such that the bearing 30 side is lower than the first guide surface 73 side.

[0062] As described above, the internal flow indicated by arrow D4 is the flow of lubricating oil along the first guide surface 73. Here, the second guide surfaces 75a and 75b are located on the path of the internal flow and extend in a direction intersecting the flow direction of the internal flow. Therefore, the lubricating oil transported by the internal flow collides with either of the second guide surfaces 75a or 75b. Furthermore, the flow direction of the lubricating oil changes. Figure 3In the example, the lubricating oil delivered via the internal flow indicated by arrow D4 collides with the second guide surface 75b. However, on shaft 6... Figure 3 When the internal flow rotates counterclockwise, the flow direction of the internal flow is opposite to that of arrow D4, so the lubricating oil transported by the internal flow collides with the second guide surface 75a.

[0063] like Figure 3 As indicated by the middle arrow D5, the lubricating oil that collides with the second guide surface 75b is guided radially outward by the second guide surface 75b and dispersed. This prevents the lubricating oil from being transported along the inward flow direction to the vicinity of the lower part of the oil guide 70. Therefore, it prevents the inward and outward flows from converging and interfering with each other near the lower part of the oil guide 70. Consequently, the oil discharge performance of the lubricating oil is improved, thereby enhancing the oil seal performance.

[0064] like Figure 3 As indicated by arrow D6, a portion of the lubricating oil that collides with the second guide surface 75b is also guided and dispersed towards the bearing 30 side of the cylindrical portion 71 along the axial direction by the second guide surface 75b. The lubricating oil dispersed along the axial direction of the cylindrical portion 71 by the second guide surface 75b is conveyed downward along the inclined surface 74. This further improves oil discharge performance. In particular, in the oil guide 70, the first guide surface 73 and the inclined surface 74 are interconnected via the second guide surface 75b. Therefore, the lubricating oil dispersed along the axial direction of the cylindrical portion 71 by the second guide surface 75b is easily guided to the inclined surface 74.

[0065] In the oil guide 70, two second guide surfaces 75a and 75b are respectively disposed at different circumferential positions on the cylindrical portion 71. Therefore, regardless of the rotation direction of the shaft 6, the lubricating oil transported via the internal flow collides with either the second guide surface 75a or 75b. Thus, the confluence and interference of the internal and external flows near the lower part of the oil guide 70 can be suppressed, regardless of the rotation direction of the shaft 6.

[0066] As described above, the oil guide 70 is installed in Figure 2 The sealing plate is 80. (For example...) Figure 3 As shown, on the first guide surface 73, there are two first claw portions 76, namely first claw portion 76a and first claw portion 76b, and two second claw portions 77a and second claw portion 77b, which protrude radially outward from the cylindrical portion 71. The oil guide 70 is installed on the sealing plate 80 by pressing these four claw portions into the inner circumferential surface 81a of the annular protrusion 81 of the sealing plate 80.

[0067] However, the oil guide 70 can be installed on the bearing housing 20 simply by pressing in the aforementioned claw portion. For example, the aforementioned claw portion can also be pressed into a component other than the sealing plate 80. Alternatively, for example, the aforementioned claw portion can be directly pressed into the bearing housing 20.

[0068] During the installation of the oil guide 70 using the claw portion, the installation position of the oil guide 70 is determined under the condition that forces are applied to each claw portion. Depending on the balance of forces acting on each claw portion, the coaxiality of the oil guide 70 may deteriorate. This deterioration in the coaxiality of the oil guide 70 may be a major cause of interference between the oil guide 70 and the oil baffle 60, or a localized increase in the gap between the oil guide 70 and the oil baffle 60, leading to a deterioration in oil seal performance. In this embodiment, by studying the claw portion of the oil guide 70, the coaxiality of the oil guide 70 can be improved.

[0069] Figure 4 This is a diagram illustrating the details of the claw portion of the oil guide 70 in this embodiment. (See diagram for details.) Figure 4 As shown, the oil guide 70 has four claws arranged circumferentially at intervals: a first claw 76a, a first claw 76b, a second claw 77a, and a second claw 77b.

[0070] First claw portions 76a and 76b extend radially outward from the first guide surface 73. The first claw portions 76a and 76b extend in the same plane as the first guide surface 73 and connect to the outer edge of the first guide surface 73. The first claw portions 76a and 76b have a generally rectangular flat plate shape. When viewed along the axial direction of the cylindrical portion 71, the first claw portions 76a and 76b are symmetrically arranged with respect to the axis of symmetry A2. When viewed along the axial direction of the cylindrical portion 71, the central portion of the first claw portions 76a and 76b in the circumferential direction is located on the side opposite to the second guide surfaces 75a and 75b with respect to the orthogonal axis A3. Therefore, in Figure 4 In the example, when viewed along the axial direction of the cylindrical portion 71, the central portion of the first claw portions 76a and 76b in the circumferential direction is located above the orthogonal axis A3. The central portion of the first claw portion 76 in the circumferential direction may be, for example, the centroid of the first claw portion 76 or the centroid of the first claw portion 76 when viewed along the axial direction of the cylindrical portion 71.

[0071] The second claw portions 77a and 77b extend radially outward from the first guide surface 73. The second claw portions 77a and 77b extend in the same plane as the first guide surface 73 and connect to the outer edge of the first guide surface 73. The second claw portions 77a and 77b have a generally rectangular flat plate shape. When viewed along the axial direction of the cylindrical portion 71, the second claw portions 77a and 77b are symmetrically arranged with respect to the axis of symmetry A2. When viewed along the axial direction of the cylindrical portion 71, the central portion of the second claw portions 77a and 77b in the circumferential direction is located on the side of the second guide surfaces 75a and 75b with respect to the orthogonal axis A3. Therefore, in Figure 4In the example, when viewed along the axial direction of the cylindrical portion 71, the central portion of the second claw portions 77a and 77b in the circumferential direction is located below the orthogonal axis A3. The central portion of the second claw portion 77 in the circumferential direction can be, for example, the centroid of the second claw portion 77 when viewed along the axial direction of the cylindrical portion 71.

[0072] like Figure 4 As shown, a force F1 acts on each of the first claw portions 76 from the central portion in the circumferential direction toward the central axis A1. A force F2 acts on each of the second claw portions 77 from the central portion in the circumferential direction toward the central axis A1. Figure 4 In this context, the magnitude and direction of forces F1 and F2 are represented by vectors.

[0073] The central axis A1 of the oil guide 70 tends to deviate from its ideal position in the direction of the resultant force of the force F1 acting on each of the first claw portions 76 and the force F2 acting on each of the second claw portions 77. Furthermore, the greater the resultant force of the force F1 acting on each of the first claw portions 76 and the force F2 acting on each of the second claw portions 77, the greater the deviation of the central axis A1 of the oil guide 70 from its ideal position.

[0074] As described above, in the oil guide 70, the second guide surfaces 75a and 75b are positioned lower than the orthogonal axis A3. Therefore, the second claw portions 77a and 77b cannot be positioned lower than the second guide surfaces 75a and 75b. Consequently, the upward component of the force F2 acting on the second claw portion 77 tends to be smaller.

[0075] Consider the case where a single claw extends radially outward from the portion directly above the first guide surface 73 (i.e., the portion overlapping the axis of symmetry A2 when viewed along the axial direction of the cylindrical portion 71), replacing the two first claw portions 76. In this case, a total of three claws—the claw positioned directly above the oil guide 70 and the two second claw portions 77—are pressed into the sealing plate 80. The force acting on the claw positioned directly above the oil guide 70 has only a downward component. Therefore, the resultant force of the forces acting on the three claws tends to be downward. Furthermore, the downward component of this resultant force tends to be larger. Consequently, the central axis A1 of the oil guide 70 tends to shift downward relative to its ideal position.

[0076] As described above, the oil guide 70 according to this embodiment has four claws: first claw portions 76a and 76b arranged on the upper side of the oil guide 70 with orthogonal axis A3 as the reference, and second claw portions 77a and 77b arranged on the lower side of the oil guide 70 with orthogonal axis A3 as the reference. These four claw portions are pressed into the sealing plate 80. The force F1 acting on the first claw portion 76 has not only a downward component but also... Figure 4The left and right components. Therefore, the downward component of the resultant force F1 acting on the two first claws 76a and 76b is easily less than the force acting on that single claw when a claw is provided directly above the oil guide 70 instead of the two first claws 76a. Therefore, the difference between the downward component of the resultant force F1 acting on the two first claws 76a and 76b and the upward component of the resultant force F2 acting on the two second claws 77a and 77b can be reduced.

[0077] Therefore, the offset of the central axis A1 of the oil guide 70 relative to the ideal position can be reduced, thereby improving the coaxiality of the oil guide 70. As a result, interference between the oil guide 70 and the oil baffle 60 can be suppressed, as well as the local increase in the gap between the oil guide 70 and the oil baffle 60, which would lead to deterioration of the oil seal performance.

[0078] In particular, in the oil guide 70 according to this embodiment, the circumferential angle θ1 from the orthogonal axis A3 to the central portion of the first claw 76 in the circumferential direction is greater than the circumferential angle θ2 from the orthogonal axis A3 to the central portion of the second claw 77 in the circumferential direction.

[0079] Angle θ1 is the angle formed by the line segment connecting the central axis A1 and the central portion of the first claw 76 in the circumferential direction, and the orthogonal axis A3, when viewed along the axial direction of the cylindrical portion 71. Angle θ2 is the angle formed by the line segment connecting the central axis A1 and the central portion of the second claw 77 in the circumferential direction, and the orthogonal axis A3, when viewed along the axial direction of the cylindrical portion 71.

[0080] As described above, the second claw portions 77a and 77b cannot be positioned below the second guide surfaces 75a and 75b. Therefore, there is a limitation that makes it difficult to increase the angle θ2. On the other hand, the positions of the first claw portions 76a and 76b can be freely set in the portion of the first guide surface 73 above the orthogonal axis A3. Therefore, the angle θ1 has a high degree of freedom.

[0081] When the first claw portion 76 approaches the second claw portion 77, the oil guide 70 easily rotates around the orthogonal axis A3. For example, suppose that in the portions of the oil guide 70 that replace the first claw portions 76a, 76b and the second claw portions 77a, 77b (specifically, in...) Figure 4 With two claws (one on the left and one on the right of the orthogonal axis A3), the oil guide 70 can easily rotate around the orthogonal axis A3. The closer the first claw 76 and the second claw 77 are, the closer it is to this condition.

[0082] On the other hand, such as Figure 4As shown, by making angle θ1 greater than angle θ2, the first claw portion 76 and the second claw portion 77 can be moved away from each other. As a result, the rotation of the oil guide 70 around the orthogonal axis A3 can be suppressed, and thus the posture of the oil guide 70 is stabilized.

[0083] However, angle θ1 can be the same as angle θ2, or it can be smaller than angle θ2.

[0084] In particular, in the oil guide 70 according to this embodiment, the circumferential length L1 of the first claw portion 76 is shorter than the circumferential length L2 of the second claw portion 77.

[0085] The outer periphery of the first claw portion 76 extends circumferentially along the cylindrical portion 71. Approximately the entire outer periphery of the first claw portion 76 is pressed into the sealing plate 80. That is, the circumferential length of the portion of the first claw portion 76 pressed into the sealing plate 80 is length L1. The outer periphery of the second claw portion 77 extends circumferentially along the cylindrical portion 71. Approximately the entire outer periphery of the second claw portion 77 is pressed into the sealing plate 80. That is, the circumferential length of the portion of the second claw portion 77 pressed into the sealing plate 80 is length L2.

[0086] The magnitude of the force acting on the claw is approximately proportional to the size of the portion of the claw into which the sealing plate 80 is pressed. Therefore, the magnitude of the force F1 acting on the first claw 76 is approximately proportional to the length L1. On the other hand, the magnitude of the force F2 acting on the second claw 77 is approximately proportional to the length L2.

[0087] As described above, the second claw portions 77a and 77b cannot be positioned lower than the second guide surfaces 75a and 75b, therefore the upward component of the force F2 acting on the second claw portion 77 tends to be smaller. Consequently, the downward component of the force F1 acting on the first claw portion 76 tends to be greater than the upward component of the force F2 acting on the second claw portion 77. Figure 4 As shown, by making the length L1 shorter than the length L2, the force F1 acting on the first claw 76 can be made smaller than the force F2 acting on the second claw 77. This makes it easier to reduce the difference between the downward component of the resultant force F1 acting on the two first claws 76a and 76b and the upward component of the resultant force F2 acting on the two second claws 77a and 77b. Therefore, it is easier to improve the coaxiality of the oil guide 70.

[0088] However, length L1 can be the same as length L2, or it can be longer than length L2.

[0089] In particular, in the oil guide 70 of this embodiment, the circumferential length L1 of the first claw 76, the circumferential length L2 of the second claw 77, the circumferential angle θ1 from the orthogonal axis A3 to the central part of the first claw 76 in the circumferential direction, and the circumferential angle θ2 from the orthogonal axis A3 to the central part of the second claw 77 in the circumferential direction satisfy the relationship expressed by the following formula (1).

[0090] 0.113×(L1×sinθ1-L2×sinθ2)<2×C···(1)

[0091] In equation (1), C is the gap between the oil guide 70 and the oil baffle 60. Specifically, the gap C is the ideal distance specified in the design as the radial distance between the inner circumferential surface of the flat portion 72 of the oil guide 70 and the outer circumferential surface of the first enlarged diameter portion 61 of the oil baffle 60.

[0092] As described above, the magnitude of the force F1 acting on the first claw 76 is approximately proportional to the length L1. Therefore, the downward component of the force F1 acting on the first claw 76 is approximately proportional to L1×sinθ1. On the other hand, the magnitude of the force F2 acting on the second claw 77 is approximately proportional to the length L2. Therefore, the upward component of the force F2 acting on the second claw 77 is approximately proportional to L2×sinθ2. Therefore, the difference between the downward component of the resultant force of the forces F1 acting on the two first claws 76a and 76b and the upward component of the resultant force of the forces F2 acting on the two second claws 77a and 77b is approximately proportional to (L1×sinθ1-L2×sinθ2) on the left side of equation (1). Therefore, the offset of the central axis A1 of the oil guide 70 relative to the ideal position is approximately proportional to (L1×sinθ1-L2×sinθ2) on the left side of equation (1).

[0093] To derive Equation (1), a practical test was conducted. In the practical test, an oil guide 70 with specific values ​​for length L1, angle θ1, length L2, and angle θ2 was prepared, and the actual offset of the central axis A1 of the oil guide 70 relative to the ideal position was calculated. The results showed that the value obtained by multiplying (L1×sinθ1-L2×sinθ2) on the left side of Equation (1) by 0.113 as a coefficient is the offset of the central axis A1 of the oil guide 70 relative to the ideal position. That is, the left side of Equation (1) corresponds to the offset of the central axis A1 of the oil guide 70 relative to the ideal position.

[0094] When the lengths L1, L2, angles θ1, and θ2 satisfy the relationship expressed by equation (1), the offset of the central axis A1 of the oil guide 70 relative to the ideal position is less than twice the value of the gap C between the oil guide 70 and the oil baffle 60. In this case, the coaxiality of the oil guide 70 is small enough to avoid contact between the inner circumferential surface of the flat portion 72 of the oil guide 70 and the outer circumferential surface of the first enlarged diameter portion 61 of the oil baffle 60. As a result, interference between the oil guide 70 and the oil baffle 60, and the deterioration of oil seal performance due to localized increase in the gap C between the oil guide 70 and the oil baffle 60 can be more effectively suppressed.

[0095] However, the length L1, length L2, angle θ1 and angle θ2 may not satisfy the relationship expressed by the above equation (1).

[0096] The embodiments of this disclosure have been described above with reference to the accompanying drawings, but this disclosure is not limited to these embodiments. Various modifications and alterations will be readily apparent to those skilled in the art within the scope of the claims, and it should be understood that these modifications and alterations also fall within the technical scope of this disclosure.

[0097] The above describes an example where the second guide surfaces 75a and 75b extend substantially parallel to the axial direction and radial direction of the cylindrical portion 71. However, the extending direction of the second guide surfaces 75a and 75b is not limited to the above example. For example, the second guide surfaces 75a and 75b may be inclined relative to the axial direction or radial direction of the cylindrical portion 71. Furthermore, the circumferential position of the second guide surfaces 75a and 75b of the oil guide 70 may also be relative to... Figure 3 and Figure 4 The example was modified.

[0098] The above describes an example of the oil guide 70 being mounted on the turbocharger TC. However, the device equipped with the oil guide 70 can also be a device other than the turbocharger TC, as long as it is a device with a bearing having a thrust bearing surface.

[0099] Symbol Explanation

[0100] 60: Oil baffle component; 70: Oil guide; 71: Cylindrical part; 71a: Outer peripheral surface; 73: First guide surface; 73a: End; 73b: End; 75: Second guide surface; 75a: Second guide surface; 75b: Second guide surface; 76: First claw part; 76a: First claw part; 76b: First claw part; 77: Second claw part; 77a: Second claw part; 77b: Second claw part; A1: Central axis; A2: Axis of symmetry; A3: Orthogonal axis; C: Clearance; L1: Length; L2: Length; TC: Intensifier; θ1: Angle; θ2: Angle.

Claims

1. An oil guide, characterized in that, have: Cylindrical section; A first guide surface extends radially outward from the outer periphery of the aforementioned cylindrical portion and is formed over a range of 180° or more along the circumference of the aforementioned cylindrical portion. Two second guide surfaces extend radially outward from the outer circumferential surface of the cylindrical portion, and extend in a direction intersecting the outer circumferential surface of the cylindrical portion and the first guide surface, and connect to the circumferential ends of the first guide surface. When viewed along the axial direction of the cylindrical portion, they are symmetrically arranged with respect to an axis of symmetry orthogonal to the central axis of the cylindrical portion; and There are a total of four claws, including two first claws and two second claws. The two first claws extend radially outward from the first guide surface and are symmetrically arranged with respect to the axis of symmetry when viewed along the axial direction. The central portion of the claws in the circumferential direction is located on the side opposite to the second guide surface with respect to an orthogonal axis that passes through the central axis and is orthogonal to the axis of symmetry. The two second claws extend radially outward from the first guide surface and are symmetrically arranged with respect to the axis of symmetry when viewed along the axial direction. The central portion of the claws in the circumferential direction is located on the side of the second guide surface with respect to the orthogonal axis.

2. The oil guide according to claim 1, characterized in that, The circumferential angle from the orthogonal axis to the central portion of the first claw in the circumferential direction is greater than the circumferential angle from the orthogonal axis to the central portion of the second claw in the circumferential direction.

3. The oil guide according to claim 1, characterized in that, The circumferential length of the first claw is shorter than the circumferential length of the second claw.

4. The oil guide according to claim 1, characterized in that, The aforementioned oil guide covers the outer periphery of the oil-blocking component. The circumferential length of the first claw, the circumferential length of the second claw, the circumferential angle from the orthogonal axis to the center of the circumferential direction of the first claw, and the circumferential angle from the orthogonal axis to the center of the circumferential direction of the second claw satisfy the relationship represented by the following formula (1).

0. 113×(L1×sinθ1-L2×sinθ2)<2×C···(1) Wherein, L1: the circumferential length of the first claw portion. L2: The circumferential length of the second claw portion mentioned above. θ1: The circumferential angle from the orthogonal axis to the central portion of the first claw in the circumferential direction. θ2: The circumferential angle from the orthogonal axis to the central portion of the second claw in the circumferential direction. C: The gap between the aforementioned oil guide and the aforementioned oil baffle.

5. A booster, characterized in that, The oil guide device is provided with any one of claims 1 to 4.

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