JP2013245662A - Supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a structure for supplying sufficient lubricating oil to a thrust bearing and a thrust collar, by simple processing.SOLUTION: A supercharger includes a thrust collar 20 fixed to a turbine shaft 7, a turbine side bearing 21 arranged in a bearing housing 2, opposed in the axial direction of the turbine shaft to the thrust collar and receiving a thrust load acting via the thrust collar from the compressor impeller 9 side, and a compressor side bearing 22 opposed in the axial direction of the turbine shaft and receiving the thrust load acting via the thrust collar from the turbine impeller 8 side, and the bearing housing is provided with an oil passage 24 for supplying the lubricating oil up to the bearing relatively positioned inside the bearing housing out of the turbine side bearing and the compressor side bearing from the bearing housing outside.

Description

  The present invention relates to a turbocharger that receives a thrust load acting on a turbine shaft with a thrust bearing.

  2. Description of the Related Art Conventionally, a turbocharger is known in which a turbine shaft having a turbine impeller provided at one end and a compressor impeller provided at the other end is rotatably held by a bearing housing. The supercharger rotates the turbine impeller by exhaust gas discharged from the engine, and rotates the compressor impeller through the turbine shaft by the rotation of the turbine impeller.

  An axial load (thrust load) acts on the turbine shaft. In order to receive this thrust load, a thrust collar and a thrust bearing are provided. The frictional force of both contact parts is reduced by the lubricating oil supplied from the oil passage provided in the turbine housing. Patent Document 1 discloses a supercharger having a configuration in which a thrust collar is sandwiched between two thrust bearings. The oil passage extends perpendicularly to the turbine shaft from the outside of the bearing housing to the front of the turbine shaft, changes direction in the axial direction, passes through the thrust collar radially outwardly, and the thrust bearing on the compressor impeller side ( To the compressor side bearing). The lubricating oil press-fitted into the oil passage is supplied to the gap between the thrust collar and the two thrust bearings through an oblique hole provided in the compressor side bearing.

JP 2011-012570 A

  Since the thrust bearing is an annular member having a small axial thickness, the machining of drilling oblique holes as described in Patent Document 1 has a high degree of difficulty and has been a factor in increasing the machining cost.

  An object of the present invention is to provide a supercharger capable of realizing a structure for supplying sufficient lubricating oil to a thrust bearing and a thrust collar in a simple and low cost manner.

  In order to solve the above problems, a turbocharger according to the present invention includes a bearing housing in which a turbine housing is fixed to one end side and a compressor housing is fixed to the other end side, and a turbine impeller accommodated in the turbine housing. A turbine shaft provided at one end and housed in the compressor housing with a compressor impeller provided at the other end; a thrust collar fixed to the turbine shaft; and provided in the bearing housing, with respect to the thrust collar A turbine-side bearing that receives a thrust load acting through the thrust collar from the compressor impeller side, and is opposed to the axial direction of the turbine shaft. Thrust load acting through A compressor side bearing received from the impeller side, and the bearing housing includes lubricating oil from an outer side of the bearing housing to a bearing positioned relatively inward of the turbine side bearing and the compressor side bearing. An oil passage for supplying the oil is provided.

  The oil path includes a main flow path extending in a radial direction of the turbine shaft, and lubricating oil from the main flow path to a bearing positioned relatively inward of the bearing housing among the turbine side bearing and the compressor side bearing. And a branch path that leads.

  The turbine-side bearing and the compressor-side bearing are provided in the vicinity of a bearing that is positioned relatively inside the bearing housing, and further include a radial bearing that receives a radial load of the turbine shaft, and the branch path includes the turbine Of the side bearing and the compressor side bearing, the bearing may be open to both the bearing positioned relatively inward of the bearing housing and the radial bearing.

  The branch path may be formed along the turbine axis.

  Of the turbine side bearing and the compressor side bearing, a bearing that is positioned relatively inward of the bearing housing is provided with an oil hole penetrating in an axial direction of the turbine shaft and through which lubricating oil flows. May be opened at a position facing the oil hole.

  The thrust collar penetrates in the axial direction of the turbine shaft and is relatively outward from the bearing housing from a bearing positioned relatively inward of the turbine housing and the compressor bearing. An auxiliary hole through which the lubricating oil flows may be provided in the bearing that is positioned.

  According to the present invention, a structure for supplying sufficient lubricating oil to the thrust bearing and the thrust collar can be realized simply and at low cost.

It is a schematic sectional drawing of a supercharger. FIG. 2 is a partially enlarged view in the vicinity of a turbine shaft in FIG. 1.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  FIG. 1 is a schematic sectional view of the supercharger 1. Hereinafter, the direction of arrow F shown in FIG. 1 will be described as the front side of the supercharger 1, and the direction of arrow R will be described as the rear side of the supercharger 1. As shown in FIG. 1, the supercharger 1 includes a bearing housing 2, a turbine housing 4 connected to the front (one end) side of the bearing housing 2 by a fastening bolt 3, and the rear (other end) side of the bearing housing 2. And a compressor housing 6 connected to each other by a fastening bolt 5.

  The bearing housing 2 is formed with a bearing hole 2a penetrating in the front-rear direction of the supercharger 1, and the turbine shaft 7 is rotatably supported by the bearing hole 2a via a radial bearing and a thrust bearing. A turbine impeller 8 is integrally fixed to a front end portion (one end) of the turbine shaft 7, and the turbine impeller 8 is rotatably accommodated in the turbine housing 4. A compressor impeller 9 is integrally fixed to the rear end (other end) of the turbine shaft 7, and the compressor impeller 9 is rotatably accommodated in the compressor housing 6.

  The compressor housing 6 is formed with an air inlet 10 that opens to the rear side of the supercharger 1 and is connected to an air cleaner (not shown). Further, in a state where the bearing housing 2 and the compressor housing 6 are connected by the fastening bolt 5, a diffuser flow path 11 that compresses and pressurizes air is formed by the facing surfaces of both the housings 2 and 6. The diffuser passage 11 is formed in an annular shape from the radially inner side to the outer side of the turbine shaft 7 (compressor impeller 9), and communicates with the intake port 10 via the compressor impeller 9 on the radially inner side. ing.

  Further, the compressor housing 6 is provided with an annular compressor scroll passage 12 positioned on the radially outer side of the turbine shaft 7 (compressor impeller 9) with respect to the diffuser passage 11. The compressor scroll passage 12 communicates with an intake port of an engine (not shown) and also communicates with the diffuser passage 11. Therefore, when the compressor impeller 9 rotates, fluid is sucked into the compressor housing 6 from the intake port 10, and the sucked fluid is boosted in the diffuser flow path 11 and the compressor scroll flow path 12 to be sucked into the engine intake port. Will be led to.

  The turbine housing 4 is formed with a discharge port 13 that opens to the front side of the supercharger 1 and is connected to an exhaust gas purification device (not shown). Further, the turbine housing 4 is provided with a flow path 14 and an annular turbine scroll flow path 15 positioned on the radially outer side of the turbine shaft 7 (turbine impeller 8) with respect to the flow path 14. The turbine scroll channel 15 communicates with a gas inlet (not shown) through which exhaust gas discharged from the exhaust port of the engine is guided, and also communicates with the channel 14 described above. Therefore, the exhaust gas guided from the gas inlet to the turbine scroll flow path 15 is guided to the discharge port 13 through the flow path 14 and the turbine impeller 8 and rotates the turbine impeller 8 in the flow process. . Then, the rotational force of the turbine impeller 8 is transmitted to the compressor impeller 9 via the turbine shaft 7, and the fluid is boosted by the rotational force of the compressor impeller 9 as described above, and the intake port of the engine Will be led to.

  FIG. 2 is a partially enlarged view of the vicinity of the turbine shaft 7 of FIG. As shown in FIG. 2, a thrust bearing 7 a that receives the thrust load of the turbine shaft 7 is provided in the bearing housing 2. The thrust bearing 7a has a turbine side bearing 21 arranged on the turbine impeller 8 side (see FIG. 1) and a compressor side bearing 22 arranged on the compressor impeller 9 side with respect to the thrust collar 20 fixed to the turbine shaft 7. , And is configured.

  The thrust collar 20 is an annular member, and is provided with a hole 20a penetrating in the axial direction in the center. The thrust shaft 20 is fixed to the turbine shaft 7 with the turbine shaft 7 inserted through the hole 20a, and rotates integrally with the turbine shaft 7. To do.

  The turbine-side bearing 21 is an annular member and is fitted into the fitting hole 2 b in the bearing housing 2. A hole 21a penetrating in the axial direction is provided at the center of the turbine-side bearing 21, and the turbine shaft 7 is inserted into the hole 21a so as to be relatively rotatable. The turbine-side bearing 21 is opposed to the thrust collar 20 in the axial direction of the turbine shaft 7 and receives a thrust load acting via the thrust collar 20 from the compressor impeller 9 side.

  The compressor-side bearing 22 is an annular member, and is opposed to the axial direction of the turbine shaft 7 and receives a thrust load acting via the thrust collar 20 from the turbine impeller 8 side. In the center of the compressor side bearing 22, a hole 22a penetrating in the axial direction is provided, and the oil draining portion 23 is inserted into the hole 22a.

  The oil draining portion 23 is provided with a through hole 23a penetrating in the axial direction, and is fixed to the turbine shaft 7 in a state where the turbine shaft 7 is inserted into the through hole 23a. At this time, the diameter of the oil draining portion 23 maintains a dimensional relationship slightly smaller than the inner diameter of the hole 22a in the compressor side bearing 22, and the turbine side of the compressor side bearing 22 fixed in the bearing housing 2 is maintained. The shaft 7 and the oil draining portion 23 are inserted so as to be relatively rotatable.

  One end of the oil draining portion 23 in the axial direction is in contact with the thrust collar 20, and the other end is in contact with the back surface of the compressor impeller 9. That is, a bolt is fastened to the end portion of the turbine shaft 7 in a state where the thrust collar 20, the oil drainage portion 23, and the compressor impeller 9 are sequentially inserted into the turbine shaft 7 from the end portion on the compressor impeller 9 side. Accordingly, the thrust collar 20, the oil drainage portion 23, and the compressor impeller 9 are clamped in the axial direction between the stepped portion of the turbine shaft 7 and the bolt by the fastening force of the bolt, and rotate integrally with the turbine shaft 7. Become. Further, the oil draining portion 23 includes a protruding portion 23b that protrudes in the radial direction from one end side that contacts the thrust collar 20, and this protruding portion 23b is provided between the compressor side bearing 22 and the compressor impeller 9. It is located. The protrusion 23b causes the lubricating oil that has reached the protrusion 23b through the hole 22a of the compressor-side bearing 22 to scatter radially outward due to centrifugal force, and suppresses the intrusion of the lubricating oil into the compressor impeller 9 side. Is.

  The radial bearing 7b is provided in the vicinity of a bearing (in the present embodiment, the turbine-side bearing 21 corresponds) that is relatively located inside the bearing housing 2 among the turbine-side bearing 21 and the compressor-side bearing 22. The radial bearing 7b is also arranged on the turbine impeller 8 side in the bearing housing 2, and receives the radial load of the turbine shaft 7 by the two radial bearings 7b.

  An oil passage 24 is formed in the bearing housing 2 by drilling. The oil passage 24 communicates with the turbine side bearing 21 and supplies lubricating oil from the outside of the bearing housing 2 to the turbine side bearing 21.

  Specifically, the oil passage 24 includes a main passage 24a extending in the radial direction of the turbine shaft 7 and a branch passage 24b branching from the main passage 24a and extending along the axial direction of the turbine shaft 7. The lubricating oil is guided to the turbine-side bearing 21 from the main flow path 24a via the branch path 24b. By configuring the oil passage 24 with the main passage 24a and the branch passage 24b, the supercharger 1 can set the flow passage area of the branch passage 24b separately from the main passage 24a, and the turbine side bearing 21 and the compressor side bearing can be set. 22 and the design corresponding to the optimum amount of lubricating oil supplied to the thrust collar 20 is facilitated.

  The branch path 24b opens to both the turbine-side bearing 21 and the radial bearing 7b (openings 24c and 24d), supplies holes for supplying the lubricating oil to the turbine-side bearing 21, and supplies the lubricating oil to the radial bearing 7b. The one hole 24b shares the hole to be used. Therefore, the supercharger 1 can shorten the overall length of the hole to be drilled and reduce the processing cost compared to the case where the holes for supplying the lubricating oil are provided in each of the turbine side bearing 21 and the radial bearing 7b. It becomes possible.

  Further, since the branch path 24b is formed along the turbine shaft 7, the positioning of the processing device with respect to the bearing housing 2 is facilitated compared to the case where the branch path 24b is a hole oblique to the axial direction. The feeder 1 can shorten the machining time and reduce the machining cost.

  The turbine-side bearing 21 is provided with an oil hole 21b that penetrates in the axial direction of the turbine shaft 7 and through which lubricating oil flows. The oil passage 24 opens at a position facing the oil hole 21b. The lubricating oil guided to the opening 24c of the branch passage 24b of the oil passage 24 is supplied to the thrust collar 20 and the compressor side bearing 22 through the oil hole 21b.

  Further, the thrust collar 20 penetrates in the axial direction of the turbine shaft 7, and assists the lubricating oil to flow from the turbine side bearing 21 to the bearing (compressor side bearing 22) relatively positioned outside the bearing housing 2. A hole 20b is provided.

  Therefore, the lubricating oil transmitted from the turbine side bearing 21 to the surface 20c of the thrust collar 20 on the turbine side bearing 21 side is supplied to the surface 20d on the opposite side of the thrust collar 20 and the compressor side bearing 22 through the auxiliary hole 20b. .

  Thus, the lubricating oil guided to the turbine side bearing 21 flows to the thrust collar 20 and the compressor side bearing 22, and reduces friction between the thrust collar 20 and the turbine side bearing 21 and the compressor side bearing 22.

  Thus, in the supercharger 1, an oil passage 24 that guides the lubricating oil to the turbine-side bearing 21 is formed instead of an oil passage that guides the lubricating oil to the compressor-side bearing 22, and an oblique hole is drilled in the compressor-side bearing 22. Even without processing, sufficient lubricating oil can be supplied to the thrust collar 20, the turbine side bearing 21, and the compressor side bearing 22 simply by forming the oil passage 24 by a simple drilling process for the bearing housing 2. It becomes possible.

  In the above-described embodiment, the case where the turbine-side bearing 21 is provided with the oil hole 21b and the thrust collar 20 is provided with the auxiliary hole 20b has been described. However, without providing either one or both of the oil hole 21b and the auxiliary hole 20b, the lubricating oil supplied to the turbine side bearing 21 travels along the outer periphery of the turbine side bearing 21 and the thrust collar 20 and then becomes the compressor side bearing 22. Flows up. Therefore, the supercharger 1 can realize a structure for supplying sufficient lubricating oil to the turbine side bearing 21, the compressor side bearing 22, and the thrust collar 20 by a simple drilling process for the bearing housing 2. . However, the turbocharger 1 can reduce the energy required for the pressure of the lubricating oil by providing the oil hole 21b in the turbine side bearing 21 and the auxiliary hole 20b in the thrust collar 20 as in the present embodiment. Become.

  In the above-described embodiment, the turbine side bearing 21, the compressor side bearing 22 and the thrust collar 20 are provided on the compressor impeller 9 side, and the turbine side bearing 21 is a bearing housing relative to the compressor side bearing 22. The case where it is located inward of 2 has been described. However, for example, the turbine side bearing 21, the compressor side bearing 22, and the thrust collar 20 may be provided on the turbine impeller 8 side. In this case, the compressor side bearing 22 is positioned inward of the bearing housing 2 relative to the turbine side bearing 21.

  In the above-described embodiment, the branch path 24b opens to both the turbine-side bearing 21 and the radial bearing 7b, and supplies a lubricating oil to the turbine-side bearing 21 and supplies the lubricating oil to the radial bearing 7b. The case where the hole to be used is shared by one branch path 24b has been described. However, in addition to the branch path 24b, a sub-flow path that is an oil path for branching from the main flow path 24a and supplying lubricating oil to the radial bearing 7b may be provided. In this case, the supercharger 1 can adjust the amount of lubricating oil supplied to the turbine side bearing 21 side and the radial bearing 7b side according to the individually set flow passage areas, and the design becomes easy.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  The present invention can be used for a supercharger that receives a thrust load acting on a turbine shaft with a thrust bearing.

DESCRIPTION OF SYMBOLS 1 ... Supercharger 2 ... Bearing housing 4 ... Turbine housing 6 ... Compressor housing 7 ... Turbine shaft 7a ... Radial bearing 8 ... Turbine impeller 9 ... Compressor impeller 20 ... Thrust collar 20b ... Auxiliary hole 21 ... Turbine side bearing 21b ... Oil hole 22 ... Compressor side bearing 24 ... Oil channel 24a ... Main channel 24b ... Branch channel

Claims (6)

A bearing housing having a turbine housing fixed to one end and a compressor housing fixed to the other end;
A turbine shaft provided at one end with a turbine impeller accommodated in the turbine housing, and a turbine shaft provided at the other end with a compressor impeller accommodated in the compressor housing;
A thrust collar fixed to the turbine shaft;
A turbine-side bearing provided in the bearing housing, facing the thrust collar in the axial direction of the turbine shaft, and receiving a thrust load acting via the thrust collar from the compressor impeller side;
A compressor-side bearing facing the axial direction of the turbine shaft and receiving a thrust load acting via the thrust collar from the turbine impeller side;
With
The bearing housing is provided with an oil passage for supplying lubricating oil from the outside of the bearing housing to a bearing positioned relatively inside the bearing housing among the turbine side bearing and the compressor side bearing. A turbocharger characterized by The oil passage is
A main flow path extending in a radial direction of the turbine shaft;
2. A branch path for guiding lubricating oil from the main flow path to a bearing relatively positioned inward of the bearing housing among the turbine side bearing and the compressor side bearing. The supercharger according to 1. A radial bearing that is provided in the vicinity of the bearing relatively positioned inside the bearing housing among the turbine side bearing and the compressor side bearing, and further receives a radial load of the turbine shaft;
The branch path is
3. The turbocharger according to claim 2, wherein the turbo bearing is open to both of the turbine-side bearing and the compressor-side bearing that are relatively located inside the bearing housing and the radial bearing. 4. .   The supercharger according to claim 2, wherein the branch path is formed along the turbine shaft. Of the turbine side bearing and the compressor side bearing, a bearing positioned relatively inside the bearing housing is provided with an oil hole penetrating in an axial direction of the turbine shaft and through which lubricating oil flows.
The supercharger according to any one of claims 1 to 4, wherein the oil passage opens at a position facing the oil hole.   The thrust collar penetrates in the axial direction of the turbine shaft, and is relatively out of the bearing housing from a bearing positioned relatively inward of the bearing housing among the turbine side bearing and the compressor side bearing. The supercharger according to any one of claims 1 to 5, wherein an auxiliary hole through which the lubricating oil is circulated is provided in a bearing located on the side.

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