JP2009121274A - Supercharger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a supercharger preventing loss of its performance due to oil leakage by restraining the oil leakage into a turbine by a simple structure. <P>SOLUTION: In this supercharger, a turbine housing and a compressor housing are provided on both sides of a bearing housing 8, and a driving shaft 4 with an impeller is inserted therethrough. A part of a flow path R2 for circulating a cooling or lubricating oil O in the bearing housing 8 is formed by an oil cooling chamber 19 provided in the upper part on the turbine housing side. A partition section 19a approximately in an arc shape creating a partition between the oil cooling chamber 19 and a turbine side seal space around the driving shaft 4 is provided, and the oil O of the cooling chamber 19 flows out of the vicinity of both ends in the circumferential direction of the partition section 19a. At least one of the both ends is a proximity end 19b approximated to the inner wall surface of a bearing casing 8 on the opposite side of the driving shaft 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a supercharger that prevents oil supplied to a bearing housing located between a turbine housing and a compressor housing from leaking into the turbine housing.

  As is well known, in a turbocharger, a turbine and a compressor are arranged on the same rotation shaft, the turbine impeller in the turbine and the compressor impeller in the compressor are connected by a drive shaft, and the turbine impeller is rotated by exhaust gas or the like. When moved, the compressor impeller is rotated via the drive shaft, and air or the like is compressed. Further, in a bearing housing that is disposed between the turbine and the compressor and accommodates a drive shaft and the like, oil is supplied to smoothly rotate the drive shaft and a bearing that supports the drive shaft and cool them. However, various measures are taken so that the oil does not leak from the periphery of the drive shaft into the turbine and the performance of the supercharger is deteriorated.

  For example, a turbocharger (so-called oil jet system) described in Patent Document 1 below communicates with a shaft support portion that supports a rotating shaft and an oil supply hole provided in the upper portion of the bearing housing inside the bearing housing. An oil supply hole extending in the axial direction of the drive shaft, an upper cooling space on the turbine housing side, and a turbine side seal space surrounding a slinger provided on the outer periphery of the rotating shaft in front of the seal portion of the turbine housing; The oil jet hole communicating from the oil supply hole to the upper cooling space is formed obliquely upward. That is, by making the oil jet hole obliquely upward, the turbine-side seal space can be made wider, and the amount of oil that reaches the seal portion by being reflected on the wall surface constituting the turbine-side seal space is reduced. Thus, oil leakage from the bearing housing into the turbine housing is prevented.

Also, the seal structure described in Patent Document 2 below employs a labyrinth structure for the sealing blade that partitions the compressor housing and the bearing housing, and includes a first plate-like body positioned on the compressor side and a turbine side. A hollow disk-shaped labyrinth blade having a gap formed therein by a second plate-like body located between the compressor housing and the bearing housing is provided. With this configuration, the labyrinth blade is curved in the axial direction by utilizing the atmospheric temperature difference in each plate, and the clearance between the outer peripheral surface of the shaft and the circular hole portion of the labyrinth blade is adjusted to prevent oil leakage. ing.
Patent Documents 3 to 5 listed below are techniques for preventing oil leakage as disclosed in Patent Documents 1 and 2 below.
JP-A-7-174029 Japanese Patent Laid-Open No. 7-119477 JP 2004-68820 A Japanese Patent Laid-Open No. 11-2136 JP 2006-837779 A

By the way, in the structure in which the upper cooling space is provided as in the supercharger described in Patent Document 1, the upper cooling space and the turbine side seal space are partitioned by the arc-shaped partitioning portion, In general, the upper cooling space and the lower space are communicated in the vicinity of the circumferential end of the section. However, when the supercharger 1 is operated at a high speed, the oil in the vicinity of both ends of the partition section is driven by the drive shaft and slinger. There is a problem that the air is wound into the turbine-side seal space by the whirling wind, etc., reaches the seal portion of the turbine housing and leaks into the turbine.
In addition, since the structure of the seal structure in Patent Document 2 is complicated, it is difficult to employ it in a small turbocharger that has space constraints. In addition, the manufacturing cost and manufacturing process are disadvantageous.

  The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a turbocharger that prevents oil from leaking into the turbine with a simple configuration and that does not impair performance due to oil leakage. It is to provide.

In order to achieve the above object, the present invention proposes the following means.
According to the first aspect of the present invention, a turbine housing and a compressor housing are provided on both sides of a bearing housing, and a drive shaft is inserted into each of the housings. An oil provided with an impeller and a compressor impeller provided on the drive shaft in the compressor housing, and a part of a flow path through which oil for cooling or lubrication in the bearing housing flows. A substantially arcuate partition formed by a cooling chamber and separating the oil cooling chamber and the turbine-side seal space around the drive shaft is provided, and oil in the upper cooling chamber is in the vicinity of both ends in the circumferential direction of the partition To the turbocharger flowing out of There are, of said end portions, at least one of, and is characterized in that has a proximal end proximate to the opposite side of the bearing casing wall of the drive shaft.

  According to a second aspect of the present invention, in the supercharger according to the first aspect, an oil outflow direction in the vicinity of the proximal end portion is a direction opposite to a rotation direction of the drive shaft. .

  According to the present invention, at least one of both ends of the partition that partitions the oil cooling chamber that forms part of the oil flow path in the bearing housing and the turbine-side seal space is provided in the bearing casing on the opposite side of the drive shaft. Since it is a close end close to the wall surface, the turbine side oil seal space near the close end is widened, and the oil outflow position is separated from the drive shaft, so that the oil flowing out from the oil cooling chamber is It is not caught in the side seal space. As a result, oil leakage into the turbine can be prevented with a simple configuration, and a turbocharger that does not impair performance can be provided.

  In addition, according to the present invention, the oil outflow direction in the vicinity of the proximity end is opposite to the rotation direction of the drive shaft. Oil leakage into the turbine can be prevented.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing an overall configuration of a supercharger 1 according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of the supercharger 1. The supercharger 1 is a so-called oil return type supercharger and is applied to an internal combustion engine of a vehicle.

  As shown in FIG. 1, the supercharger 1 is schematically composed of a turbine impeller 2, a compressor impeller 3, a drive shaft 4 to which the turbine impeller 2 and the compressor impeller 3 are fixed, and a housing 5 that houses them. It is configured.

  The turbine impeller 2 and the drive shaft 4 are integrated by welding, and the compressor impeller 3 and the drive shaft 4 are coupled via a nut 6. The housing 5 includes a turbine housing 7 in which the turbine impeller 2 is accommodated, a bearing housing 8 in which a bearing of the drive shaft 4 and the like are accommodated, a seal plate 9 that partitions the bearing housing 8 and the compressor housing 10, and a compressor The compressor housing 10 in which the impeller 3 is accommodated is connected in order.

  In the supercharger 1, oil O is supplied to the inside of the bearing housing 8 in order to smoothly slide the drive shaft 4 and the bearings that support the drive shaft 4 and to cool the drive shaft 4 and the housing 5. . Therefore, an oil supply port 11 for supplying oil O from the outside is provided in the upper portion of the bearing housing 8, and an oil discharge port 12 for discharging the oil O from the inside is provided in the lower portion of the bearing housing 8. . In the figure, the dashed arrow indicates the flow of the oil O.

  Inside the bearing housing 8, there is a shaft support portion 13 through which the drive shaft 4 is inserted to form a large diameter on the compressor side, an oil discharge chamber 14 surrounding the shaft support portion 13, and the shaft support portion 13. A first oil supply hole 15 that is perforated along the shaft support portion 13 in the upper part and communicates perpendicularly to the oil supply port 11 is provided.

  The shaft support portion 13 is provided with a floating metal (bearing) 16 on the turbine side and a floating metal 17 on the compressor side. The floating metals 16 and 17 are cylindrical members having a plurality of through holes on the peripheral surface, and the drive shaft 4 is supported in the radial direction via these so as to be rotatable. That is, when oil O is supplied to the floating metals 16 and 17 from the second oil supply hole 22 and the third oil supply hole 23 which will be described later, between the floating metals 16 and 17 and the shaft support portion 13 and between the drive shaft 4 and the floating metal 16. , 17, and the oil O spreads between them, and the drive shaft 4 can be smoothly rotated even at a high rotational speed. The floating metals 16 and 17 cannot be moved in the axial direction by a retaining ring 16a or a bearing spacer 17a provided on the shaft support portion 13.

  The oil discharge chamber 14 is provided in the lower oil discharge space 18 that communicates with the oil discharge port 12, the upper cooling space 19 that surrounds the upper portion of the shaft support 13 on the turbine side, and the outer periphery of the connection portion between the drive shaft 4 and the turbine impeller 2. A turbine-side seal space 21 surrounding the slinger 20 is provided.

3 is a cross-sectional view taken along the line III-III in FIG. 2, and FIG. 4 is a partial cross-sectional view of the supercharger 1.
As shown in FIG. 3, an upper cooling space (upper cooling chamber) 19 is provided on the upper portion of the bearing housing 8 so as to surround the drive shaft 4, the shaft support portion 13 (see FIG. 2) and the slinger 20 in an arc shape. Space. The upper cooling space 19 is partitioned from the turbine-side seal space 21 by providing a partition portion 19a having a substantially arc-shaped cross section on the turbine side, and is provided at the adjacent end portion 19b and end portion 19c in the circumferential direction of the partition portion 19a. The upper cooling space 19 and the lower oil discharge space 18 communicate with each other through the elongated holes 19B and 19C formed along the same. Further, as shown in FIG. 4, the upper cooling space 19 communicates with an oil return hole 25 described later on the compressor side.

  The proximity end 19b of the partition portion 19a is formed so as to be closer to the bearing housing inner wall surface 8c than the end 19c, and the long hole 19B is smaller than the long hole 19C by the close length. It has become.

  The turbine-side seal space 21 has a semicircular arc shape formed by the partition portion 19a, and is disposed between the upper cooling space 19 and the lower oil discharge space 18 so as to surround the upper half of the slinger 20. It is provided. In addition, the slinger 20 blows off the oil O transmitted to the drive shaft 4 from the compressor side toward the turbine side in the radial direction.

  With such a configuration, the partition portion 19a discharges the oil O in the upper cooling space 19 to the lower oil discharge space 18 so as to avoid the slinger 20 and a seal portion 40 described later, and the slinger 20 causes the radial direction thereof to The oil O blown to the upper side of the oil is collided with the wall surface on the drive shaft 4 side and then flows down to the lower oil discharge space 18.

  The first oil supply hole 15 includes a second oil supply hole 22 and a third oil supply hole 23 that supply oil O from the first oil supply hole 15 to the floating metals 16 and 17, and the oil O supplied to the floating metals 16 and 17 at the bottom. An oil drain hole 24 for discharging to the oil drain space 18 is provided.

  5 is a VV cross-sectional view in FIG. 2, and FIG. 4 is a VI-VI cross-sectional view in FIG. Inside the bearing housing 8, oil return holes 25 a and 25 b communicating obliquely from the vicinity of the center of the thrust bearing mounting surface 8 a toward the upper cooling space 19 are provided. The oil return holes 25a and 25b are opened at the same distance from the rotation center axis of the drive shaft 4 and at the same position in the vertical direction.

  Referring back to FIGS. 1 and 2, the load in the thrust direction of the drive shaft 4 is the turbine side thrust bearing (hereinafter referred to as “T side thrust bearing”) 26, the thrust collar 27, and the compressor side thrust bearing (hereinafter referred to as C side). This is called a thrust bearing.

The T-side thrust bearing 26 is attached to the shaft support portion 13 from the compressor side, and is disposed so as to contact the compressor-side end surface of the floating metal 17 and the flat surface 8 b of the bearing housing 8.
The thrust collar 27 fixed to the drive shaft 4 has a C-side thrust bearing 30 and a C-side thrust bearing 30 which are fixed to the thrust bearing mounting surface 8a by a screw (not shown). It is arranged so as to be sandwiched between.
That is, the thrust collar 27 transmits the axial load generated on the drive shaft 4 to the T-side thrust bearing 26 and the C-side thrust bearing 30, and the air pressure applied to the drive shaft 4 by the T-side thrust bearing 26 and the C-side thrust bearing 30. It is configured to support axial force due to gas pressure and vibration.

  7A and 7B are diagrams showing the C-side thrust bearing 30. FIG. 7A is a top view, FIG. 7B is a front view, and FIG. 7C is a cross-sectional view taken along line cc in FIG. FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG.

  As shown in FIG. 7A, the C-side thrust bearing 30 is a disk-shaped member, and the drive shaft 4 is inserted in the vicinity of the center of the inner surface 31 and the outer surface 32 through an oil drill 42 described later. The hole 33 penetrates. Further, the inner surface 31 is positioned on the outer peripheral side and is in contact with the thrust bearing mounting surface 8a of the bearing housing 8 and is in contact with the thrust collar 27 which is positioned around the insertion hole 33 and slides therewith. Four pads 31b are provided.

A first oil groove 34 is formed in a substantially semicircular arc shape along the outer periphery of the C-side thrust bearing 30 at the upper part of the contact surface 31a. The first oil groove 34 is an oval groove deeper than the first oil groove 34. Five pocket grooves 35 (35a, 35b) having grooves are provided along the first oil groove 34 at substantially equal intervals. Of these five pocket grooves 35, the pocket grooves 35 b other than the pocket grooves 35 a provided at the position corresponding to the first oil supply hole 15 (see FIG. 5) above the C-side thrust bearing 30 are shown in FIG. As shown in FIG. 8A and FIG. 8, an oil supply port 36 communicating with the pad 31b is provided.
Further, as shown in FIG. 7 (a), an oil storage portion 37 is provided below the abutting surface 31a in a fan shape and as shown in FIG. .

  The pad 31b has a fan shape that contacts and slides on the thrust collar 27. The oil supply port 36 is opened on the sliding surface of each pad 31b, and is formed in two steps between the pads 31b. Groove is provided.

  A second oil groove 38 is formed in a substantially arc shape between the contact surface 31a and the pad 31b, and communicates with the four grooves between the oil reservoir 37 and each pad 31b. Further, the second oil groove 38 is provided with two oil passage grooves 38a, 38b having an enlarged area at positions corresponding to the outlets 25a, 25b of the two oil return holes 25a, 25b in the bearing housing 8. It has been.

  As shown in FIG. 7A, the C-side thrust bearing 30 forms a bearing flow path r by contacting the thrust bearing mounting surface 8a. That is, the bearing flow path r is formed in the pocket grooves 35b after the oil O supplied from the first oil supply holes 15 to the pocket grooves 35a of the thrust bearing 30 reaches the pocket grooves 35b via the first oil grooves 34. The oil flows into the formed oil supply port 36 and flows out from the oil supply port 36 of the pad 31b. The second oil groove 38 and the second oil groove 38 are formed mainly through two grooves formed between the pads 31b. These are a series of channels that flow through an annular channel formed by the oil reservoir 37.

Further, the first flow path R1 and the second flow path R2 are formed in the bearing housing 8 by the configuration described above.
As shown in FIG. 2, the first flow path R <b> 1 is formed in the shaft support portion 13 after the oil O supplied from the oil supply port 11 to the first oil supply hole 15 passes through the second oil supply hole 22 and the third oil supply hole 23. Into the lower oil discharge space 18 through the oil discharge hole 24 and discharged from the oil discharge port 12.
In the second flow path R2, the oil O that has flowed in the compressor direction of the first oil supply hole 15 flows into the oil return hole 25 after passing through the bearing flow path r formed by the thrust bearing 30 and the bearing housing 8, and the upper cooling is performed. It reaches the use space 19, flows down from the long holes 19 </ b> B and 19 </ b> C to the lower oil discharge space 18, and is discharged from the oil discharge port 12.

Returning to FIG. 1, reference numeral 40 is a seal portion formed on the turbine side of the bearing housing 8, and 41 is a seal portion formed on the compressor side of the bearing housing 8.
The seal portion 40 is configured such that oil O does not leak into the compressor by a groove portion 42 formed in the slinger 20 and a seal ring 43 fixed to the bearing housing 8.

Next, the operation of the supercharger 1 having the above-described configuration will be described. When the turbine impeller 2 is rotated by the relatively high temperature exhaust gas of the internal combustion engine, the rotational force is transmitted to the compressor impeller 3 via the drive shaft 4. . And the air compressed with rotation of the compressor impeller 3 is supplied to an internal combustion engine. The rotation speed of the drive shaft 4 is, for example, tens of thousands to several hundred thousand rpm.

As the turbine impeller 2 rotates, oil O is supplied into the bearing housing 8 by a pressure device (not shown) provided in the vehicle.
First, as shown in FIGS. 1 and 2, the oil O reaches the first oil supply hole 15 after flowing into the oil supply port 11, and the flow is divided into the first flow path R1 and the second flow path R2. As described above, the oil O that has flowed into the first flow path R1 flows into the shaft support portion 13 through the second oil supply hole 22 and the third oil supply hole 23, and then flows into the lower oil discharge space 18 through the oil discharge hole 24. And is discharged from the oil discharge port 12.

  On the other hand, the oil O that has flowed into the second flow path R2 passes through the bearing flow path r that is a part of the second flow path R2, as shown in FIG. 25b flows into the upper cooling space 19 by substantially the same amount.

The oil O flowing into the upper cooling space 19 flows while cooling the bearing housing 8 on the upper surface of the partition portion 19a toward the long holes 19B and 19C in the circumferential direction as shown in FIG.
Then, the oil O that has reached the proximal end portion 19b and the end portion 19c does not get caught in the turbine-side seal space 21, flows down into the lower oil discharge space 18, and is discharged from the oil discharge port 12 (FIG. 1, see FIG.

  Thus, the supercharger 1 operates stably, and the air compressed with the rotation of the compressor impeller 3 is stably supplied to the internal combustion engine.

  As described above, according to the supercharger 1, since one of the both end portions of the partition portion 19a is the proximal end portion 19b, the oil O flowing out from the oil cooling chamber 19 is caught in the turbine-side seal space 21. Thus, the seal portion 40 is not reached. That is, if both ends are provided on the drive shaft 4 side like the end 19c, the drive shaft 4 and the slinger 20 rotate at a high speed. The oil O is caught in the space 21, adheres to the turbine side of the slinger 20, reaches the seal portion 40, or is blown off by the seal portion 40, and the oil O leaks from the seal portion 40.

  However, according to the supercharger 1, since one of the partition portions 19a is the close end portion 19b, the turbine-side seal space 21 is widened, and the position where the oil O flows out is separated from the drive shaft 4. Thus, the oil O flowing out from the oil cooling chamber 19 is not caught in the turbine-side oil space 21 even by the whirling accompanying the rotation of the drive shaft 4 and the slinger 20.

  In addition, since one end of the partition portion 19a that flows down so that the oil O opposes the rotation direction of the drive shaft 4 is the close end portion 19b, it is possible to efficiently prevent the oil O from being caught. it can. In other words, when the direction in which the oil O flows down is opposite to the direction of rotation of the drive shaft 4, the oil O tends to be entangled in the turbine-side seal space 21 because it opposes the direction of the whirlwind associated with the rotation of the slinger 20 or the like. . On the other hand, when the oil O flows down in the same direction as the rotation direction of the drive shaft 4, the oil O does not run backward in the direction of the whirlwind accompanying the rotation of the slinger 20 or the like, so the oil O flows down as it is and the turbine side seal space 21. It is hard to get caught in. Therefore, if one end of the oil O flowing down in the direction opposite to the rotation direction of the drive shaft 4 is the proximal end 19b, the oil O can be effectively prevented from being entrained, and the oil can be leaked with a high effect. It becomes possible to prevent.

Note that the operation procedures shown in the above-described embodiments, the shapes and combinations of the constituent members, and the like are examples, and can be variously changed based on design requirements and the like without departing from the gist of the present invention.
For example, in the above-described embodiment, one of the both end portions of the partition portion 19a is the proximal end portion 19b, but a certain effect can be expected even if the other end portion 19c is the proximal end portion. Of course, both end portions may be formed as close end portions.

  In the above embodiment, the present invention is applied to a so-called oil return system, but may be applied to a so-called oil jet system.

It is sectional drawing which shows the whole structure of the supercharger 1 in one Embodiment of this invention. 1 is a partially enlarged view of a supercharger 1 according to an embodiment of the present invention. It is sectional drawing of the supercharger 1 in one Embodiment of this invention, Comprising: It is III-III sectional drawing in FIG. It is a partial sectional view of supercharger 1 in one embodiment of the present invention. It is sectional drawing of the supercharger 1 in one Embodiment of this invention, Comprising: It is VV sectional drawing in FIG. It is sectional drawing of the supercharger 1 in one Embodiment of this invention, Comprising: It is VI-VI sectional drawing in FIG. It is a figure which shows the C side thrust bearing 30 of the supercharger 1 in one Embodiment of this invention. It is sectional drawing of the C side thrust bearing 30 in one Embodiment of this invention, Comprising: It is VIII-VIII sectional drawing in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Supercharger 2 ... Turbine impeller 3 ... Compressor impeller 4 ... Drive shaft 7 ... Turbine housing 8 ... Bearing housing 10 ... Compressor housing 19 ... Upper cooling space 19a ... Partition part 19b ... Proximal end part 19c ... End part 21 ... Turbine side seal space O ... Oil R1 ... First flow path (flow path)
R2 ... Second channel (channel)
r ... Bearing flow path (flow path)

Claims (2)

A turbine housing and a compressor housing are provided on both sides of the bearing housing, and a drive shaft is inserted into each of the housings. A turbine impeller is provided on the drive shaft in the turbine housing and the compressor housing. A compressor impeller is provided on the drive shaft in the inside,
A part of a flow path for circulating cooling or lubricating oil in the bearing housing is formed by an oil cooling chamber provided at the turbine housing side upper part,
A supercharger provided with a substantially arc-shaped partition that partitions the oil cooling chamber and the turbine-side seal space around the drive shaft, and the oil in the upper cooling chamber flows out from the vicinity of both ends in the circumferential direction of the partition In
The supercharger according to claim 1, wherein at least one of the two end portions is a close end portion close to an inner wall surface of the bearing casing opposite to the drive shaft. The turbocharger according to claim 1, wherein
The supercharger according to claim 1, wherein an oil outflow direction in the vicinity of the proximity end is opposite to a rotation direction of the drive shaft.

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