JP5983147B2 - Turbocharger - Google Patents

Description

  The present invention relates to a supercharger in which lubricating oil is supplied to a bearing hole.

  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. Such a supercharger is connected to the engine, the turbine impeller is rotated by exhaust gas discharged from the engine, and the compressor impeller is rotated through the turbine shaft by the rotation of the turbine impeller. Thus, the supercharger compresses air and sends it to the engine as the compressor impeller rotates.

  The bearing housing has a bearing hole extending in the axial direction of the turbine shaft, and a bearing portion is disposed in the bearing hole. Then, lubricating oil for lubricating the turbine shaft and the bearing portion is supplied from the outside of the bearing housing to the bearing hole. The lubricating oil after lubricating the bearing portion is discharged from both ends of the bearing hole to the outside of the bearing hole. For example, in Patent Document 1, an oil drainage path is provided on the turbine impeller side of the bearing hole, and the lubricating oil after lubricating the bearing portion from the oil drainage path is drained. Further, there is described a configuration in which an oil passage (cooling oil passage) for cooling oil is provided in the bearing housing to cool the turbine impeller side of the bearing housing that becomes high temperature.

  The cooling oil passage is annularly provided on the turbine impeller side inside the bearing housing and radially outward of the lubricating oil drain passage. The cooling oil passage and the drainage passage communicate with one drainage space in the vertically downward direction and are drained out of the bearing housing. At this time, if the cooling oil guided from the cooling oil passage to the oil draining space interferes with the lubricating oil guided from the oil draining passage to the oil draining space, both oil draining properties are deteriorated. Therefore, in order to prevent interference between the cooling oil and the lubricating oil in the oil discharge space, a partition part that partitions the cooling oil path and the drain oil path is provided, and the partition part suppresses interference between the flow of the cooling oil and the lubricating oil. ing.

Japanese Utility Model Publication No. 63-102933

  When there is a large amount of lubricating oil guided from the end of the bearing hole to the oil drainage passage, there is a risk that the lubricating oil guided to the oil drainage passage will travel along the turbine shaft and reach the turbine impeller, resulting in a lubricant leakage. Therefore, the bearing housing may be provided with a through hole that communicates with the bearing hole and discharges the lubricating oil vertically downward from the bearing hole, thereby reducing the amount of the lubricating oil guided to the oil drain passage. However, since the partition part is positioned vertically below the through hole, the flow of the lubricating oil discharged from the through hole is hindered by the partition part, and the oil drainage from the through hole may be deteriorated.

  And if the oil drainage from a through-hole falls, the amount of lubricating oil which ejects from the edge part of a bearing hole will increase, and lubricating oil will leak to the compressor impeller side and the turbine impeller side eventually.

  An object of the present invention is to provide a supercharger that can improve oil drainage of a bearing hole in which a bearing portion is arranged and reduce leakage of lubricating oil to the impeller side.

In order to solve the above problems, a supercharger according to the present invention includes a supercharger main body, a bearing hole formed in the supercharger main body, a rotatably inserted through the bearing hole, and a turbine impeller at one end. a turbine shaft the compressor impeller provided on the other end with provided, wherein is accommodated in the bearing bore, the bearing unit having two sliding surfaces for rotatably supporting the turbine shaft, the lubricating oil to the bearing portion A lubricating oil passage to be supplied and formed in the turbocharger main body, communicated with the turbine impeller side from both of the two sliding surfaces of the bearing hole , and lubricated with lubricating the bearing portion. A through hole that is discharged from the hole, and is provided in the turbocharger main body, is located between the bearing hole and the turbine impeller of the turbine shaft, and travels from the bearing hole to the turbine impeller through the turbine shaft. Lubricant , A scattering space that scatters as the turbine shaft rotates, a cooling oil passage that is formed in the supercharger main body and through which cooling oil that cools the supercharger main body flows, the scattering space, the through hole, And the lubricating oil that is in communication with the cooling oil passage, lubricates the bearing portion, and the oil discharge space that is guided by dripping the cooling oil that has cooled the supercharger main body, and the splash space is defined as the section. Among the wall portions of the turbocharger main body, the oil supply space protrudes from the wall portion closer to the turbine impeller than the scattering space, and the lubricating oil discharged from the scattering space is dropped on the upper surface, A partition portion for positioning a communicating portion to the oil discharge space in the cooling oil passage on a lower surface side opposite to the upper surface, and a distal end portion in a protruding direction of the partition portion is an axis of the turbine shaft The direction position is vertically below the through hole. And it is located in the turbine impeller side of the end portion.

  A thrust bearing disposed on the compressor impeller side of the bearing hole and receiving a thrust load of the turbine shaft is further provided, and the lubricating oil passage and the cooling oil passage communicate with the thrust bearing to lubricate the thrust bearing. Later lubricating oil may flow through the cooling oil passage as cooling oil.

  The partition may be inclined vertically downward from the proximal end side toward the distal end side.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to improve the oil drainage property of the bearing hole by which a bearing part is distribute | arranged, and to reduce the leakage of the lubricating oil to the impeller side.

It is a schematic sectional drawing of a supercharger. It is the elements on larger scale inside the bearing housing of FIG. It is explanatory drawing for demonstrating a cooling oil path. It is explanatory drawing for demonstrating the flow of a cooling oil and lubricating oil.

  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 cross-sectional view of the supercharger C. Hereinafter, the direction of arrow F shown in FIG. 1 will be described as the front side of the supercharger C, and the direction of arrow R will be described as the rear side of the supercharger C. As shown in FIG. 1, the supercharger C includes a supercharger main body 1. The supercharger body 1 includes a bearing housing 2, a turbine housing 4 connected to the front side of the bearing housing 2 by a fastening bolt 3, a compressor housing 6 connected to the rear side of the bearing housing 2 by a fastening bolt 5, Are formed integrally.

  The bearing housing 2 is formed with a bearing hole 2a penetrating in the front-rear direction of the supercharger C (the axial direction of the turbine shaft 7), and the turbine shaft 7 is supported by the bearing portion 20 accommodated in the bearing hole 2a. It is pivotally supported. 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 C 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 C 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 passage 15 communicates with a gas inlet through which exhaust gas discharged from an exhaust manifold of an engine (not shown) is guided, and also communicates with the passage 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 inside of the bearing housing 2 of FIG. 1, and shows a portion surrounded by a broken-line square in FIG. Hereinafter, the support structure of the turbine shaft 7 by the bearing portion 20 accommodated in the supercharger main body 1 will be described with reference to FIG.

  In the present embodiment, the bearing portion 20 includes a radial bearing 21 and a thrust bearing 22. Of the bearing hole 2a of the bearing housing 2, a radial bearing 21 is disposed at a portion having a small diameter, and a thrust bearing 22 is disposed at a portion having a large diameter on the compressor impeller 9 side.

  The radial bearing 21 is made of a so-called semi-floating metal that generates a sliding motion with the turbine shaft 7 and generates an oil film pressure with the turbine shaft 7. The radial bearing 21 is provided with an insertion hole 21a penetrating in the axial direction and a pin hole 21b penetrating in a direction perpendicular to the axial direction. The bearing housing 2 is formed with a screw hole 2b that penetrates from the radially outer side to the inner side of the bearing hole 2a and faces the pin hole 21b of the radial bearing 21 accommodated in the bearing hole 2a. A pin 21c is screwed into and fixed to the screw hole 2b. By inserting the tip of the pin 21c into the pin hole 21b of the radial bearing 21, the radial bearing 21 moves in the rotational direction and the axial direction. Is regulated.

  The radial bearing 21 is a turbine in which inner peripheral surfaces 21d and 21e on the compressor impeller 9 side (right side in FIG. 2) and the turbine impeller 8 side (left side in FIG. 2) are respectively inserted into the insertion holes 21a. Vibration is suppressed by the lubricating oil that becomes a sliding surface with the shaft 7 and flows between the outer peripheral surfaces 21f and 21g and the bearing hole 2a.

  One thrust bearing 22 is arranged on each side of the axial direction of the thrust collar 23 fixed to the compressor impeller 9 side of the turbine shaft 7 and receives the axial load of the turbine shaft 7.

  The lubricating oil passage 24 is configured to include a hole communicating from the outside of the bearing housing 2 (supercharger main body 1) to the bearing portion 20, and supplies the lubricating oil to the bearing portion 20 from the outside of the bearing housing 2.

  Of the bearing portion 20, the lubricating oil supplied to the radial bearing 21 is discharged from both ends of the bearing hole 2a in the axial direction of the turbine shaft 7, and the lubricating oil discharged to the compressor impeller 9 side of the bearing hole 2a is The thrust bearing 22 is lubricated and discharged vertically downward.

  On the other hand, the lubricating oil discharged to the turbine impeller 8 side of the bearing hole 2 a reaches the slinger 25 along the turbine shaft 7. Specifically, the slinger 25 is a projecting portion that is located between the turbine impeller 8 and the bearing hole 2a in the turbine shaft 7 and projects annularly in the radial direction of the turbine shaft 7. It is scattered in the radial direction of the shaft 7.

  Further, a scattering space 26 is formed around the slinger 25 in the bearing housing 2. The scattering space 26 is located between the bearing hole 2 a and the turbine impeller 8 of the turbine shaft 7. As the slinger 25 rotates, the lubricating oil that travels from the bearing hole 2 a to the turbine impeller 8 through the turbine shaft 7 scatters in the scattering space 26.

  Lubricating oil scattered vertically above the slinger 25 travels along the inner wall of the bearing housing 2 that defines the scattering space 26, and flows down the oil drain passage 2 c together with the lubricating oil scattered vertically below the slinger 25.

  Further, the bearing housing 2 is provided with a through hole 2d that communicates with the bearing hole 2a in the radial direction of the turbine shaft 7 and opens vertically downward, and the lubricating oil guided to the bearing hole 2a is It is made to discharge | emit vertically downward also from 2d of through-holes.

  In this embodiment, in addition to the oil passage through which the lubricating oil for lubricating the bearing portion 20 flows, a cooling oil passage through which the cooling oil for cooling the bearing housing 2 flows is provided. Here, for the sake of easy understanding, the expressions of lubricating oil and cooling oil are separated, but both are oils of the same component and are used in a circulating manner.

  FIG. 3 is an explanatory diagram for explaining the cooling oil passage 30, and shows a portion surrounded by a square indicated by an alternate long and short dash line in FIG. 1. FIG. 3A shows an extracted part of the cross section of the bearing housing 2, and FIG. 3B shows a cross section taken along line III (b) -III (b) of FIG. 3A.

  As shown in FIG. 3, the cooling oil passage 30 is provided in an annular shape on the turbine impeller 8 side inside the bearing housing 2 and radially outward of the turbine shaft 7 of the oil discharge passage 2 c. The cooling oil passage 30 communicates with a portion where the thrust bearing 22 is disposed by a flow path indicated by a broken line in FIG. 3A, and the lubricating oil after lubricating the thrust bearing 22 circulates as cooling oil. .

  The cooling oil passage 30 communicates with the oil drain space 2e vertically below. The oil discharge space 2e communicates with the splash space 26, the through hole 2d, and the cooling oil passage 30. The lubricating oil that lubricates the bearing portion 20 and the cooling oil that cools the bearing housing 2 are dropped and guided. It is burned. Then, the lubricating oil and the cooling oil guided to the oil discharge space 2e are discharged out of the bearing housing 2 through the opening 2f vertically below the oil discharge space 2e.

  The partition portion 31 is provided so as to protrude from the wall portion 26a closer to the turbine impeller 8 than the scattering space 26 to the oil drainage space 2e among the wall portions of the bearing housing 2 that defines the scattering space 26, and from the proximal end side to the distal end It is inclined vertically downward toward the side.

  The partition portion 31 is discharged from the end portion of the bearing hole 2a into the scattering space 26, dripping the lubricating oil flowing through the oil drain passage 2c onto the upper surface 31a, and on the lower surface 31b side opposite to the upper surface 31a. Next, the communication part 30a to the oil drain space 2e in the cooling oil passage 30 is located.

  Cooling oil guided from the cooling oil passage 30 to the oil discharge space 2e by the partition portion 31, and lubricating oil guided from the end of the bearing hole 2a to the oil discharge space 2e via the scattering space 26 and the oil discharge passage 2c Since the interference of the flow is suppressed and the partition portion 31 is inclined, the cooling oil and the lubricating oil can be promptly guided to the opening 2f of the oil discharge space 2e.

  FIG. 4 is an explanatory diagram for explaining the flow of the cooling oil and the lubricating oil. FIG. 4A shows a cross-section at a position corresponding to FIG. 3A of the bearing housing 2 of the present embodiment. FIG. 4B shows a cross section of a position corresponding to FIG. 3A of the bearing housing B of the comparative example.

As shown in FIG. 4 (b), in the comparative example, the tip S ₁ of the partition portion S reaches a position vertically below the opening of the through hole P. Therefore, the flow of lubricating oil from the through hole P (indicated by an arrow a in FIG. 4B) and the flow of lubricating oil from the oil drainage path E (indicated by an arrow b in FIG. 4B) May interfere with each other, and the oil drainage of the lubricating oil from the bearing hole H may be reduced.

  On the other hand, in the present embodiment, as shown in FIG. 4A, the tip 31c of the partition portion 31 has a turbine impeller in which the axial position of the turbine shaft 7 is higher than the end portion 2g vertically below the through hole 2d. Located on the 8th side. FIG. 3A shows a line L extending vertically downward from the position of the end on the turbine impeller 8 side in the end 2g.

  Then, the flow of the lubricating oil in the oil discharge passage 2c (indicated by an arrow b in FIG. 4A) transmitted through the upper surface 31a of the partition portion 31 is closer to the turbine impeller 8 side than the end portion 2g of the through hole 2d. Heading vertically downward from the partition 31.

  Therefore, the flow of the lubricating oil in the oil discharge passage 2c hardly interferes with the flow of the lubricating oil discharged from the through hole 2d (indicated by an arrow a in FIG. 4A), and the oil discharge performance of the bearing hole 2a is improved. To do. Thus, leakage of lubricating oil to the turbine impeller 8 side and the compressor impeller 9 side is suppressed.

  In the above-described embodiment, the case where the lubricating oil after lubricating the thrust bearing 22 is guided to the cooling oil passage 30 as the cooling oil has been described. However, the cooling oil is supplied to the cooling oil passage 30 through a different path from the lubricating oil. You may be guided.

  Moreover, although the bearing part 20 demonstrated the case where the bearing part 20 was comprised with both the radial bearing 21 and the thrust bearing 22 in embodiment mentioned above, the bearing part 20 is comprised only with the semi-floating metal (radial bearing 21), The end surface in the axial direction of the semi-floating metal may function as a thrust bearing.

  Moreover, although embodiment mentioned above demonstrated the case where the radial bearing 21 was comprised with a semi-floating metal, the radial bearing 21 may be comprised with a full floating metal and a rolling bearing.

  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 in which lubricating oil is supplied to a bearing hole.

C ... supercharger 1 ... supercharger body 2 ... bearing housing 2a ... bearing hole 2d ... through hole 2e ... oil drain space 2g ... end 7 ... turbine shaft 8 ... turbine impeller 9 ... compressor impeller 20 ... bearing 21 ... Radial bearing (bearing part)
22 ... Thrust bearing 24 ... Lubricating oil passage 30 ... Cooling oil passage 30a ... Communication portion 31 ... Partition portion 31a ... Upper surface 31b ... Lower surface 31c ... Tip

Claims (3)

A turbocharger body;
A bearing hole formed in the supercharger body;
A turbine shaft rotatably inserted into the bearing hole, provided with a turbine impeller at one end and a compressor impeller at the other end;
A bearing portion having the accommodated in the bearing bore, the two sliding surfaces that rotatably supports the turbine shaft,
A lubricating oil passage for supplying lubricating oil to the bearing portion;
A through hole formed in the supercharger main body, communicating with the turbine impeller side from both of the two sliding surfaces of the bearing hole, and discharging lubricating oil that has lubricated the bearing portion from the bearing hole; ,
Lubricating oil provided in the turbocharger body, located between the bearing hole and the turbine impeller of the turbine shaft, and traveling from the bearing hole to the turbine impeller through the turbine shaft, A scattering space that scatters with rotation,
A cooling oil passage formed in the supercharger main body and through which a cooling oil for cooling the supercharger main body flows;
A fluid that communicates with the scattering space, the through-hole, and the cooling oil passage, lubricates the bearing, and an oil discharge space that is guided by dripping the cooling oil that has cooled the supercharger body;
Among the wall portions of the turbocharger main body that define the scattering space, the lubrication is provided so as to protrude from the wall portion closer to the turbine impeller than the scattering space to the oil discharge space and discharged from the scattering space. A partition portion for dropping oil on the upper surface, and on the lower surface side located on the opposite side of the upper surface, a partition portion for positioning the communicating portion to the oil discharge space in the cooling oil passage;
With
The turbocharger is characterized in that the tip end portion in the protruding direction of the partition portion is such that the axial position of the turbine shaft is located closer to the turbine impeller side than the vertically lower end portion of the through hole. . A thrust bearing disposed on the compressor impeller side of the bearing hole and receiving a thrust load of the turbine shaft;
The lubricating oil passage and the cooling oil passage communicate with the thrust bearing, and the lubricating oil after lubricating the thrust bearing flows through the cooling oil passage as cooling oil. Turbocharger.   The supercharger according to claim 1, wherein the partition portion is inclined vertically downward from the proximal end side toward the distal end side.

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