JP2008240522A - Oil thrower device for turbine shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil thrower device for a turbine shaft improving exclusion performance of lubricating oil shaken off by a centrifugal force by rotation of the turbine shaft. <P>SOLUTION: The oil thrower device for a turbine shaft comprises: the turbine shaft 2; an oil thrower part 9 coaxially disposed with respect to the turbine shaft 2; and a housing 5 housing the turbine shaft 2 and the oil thrower part 9. A peripheral wall 10 at a position opposed to the oil thrower part 9 out of an inner wall of the housing 5 is coated with oil repellent film 8 made from oil repellent material such as fluorine resin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a turbine shaft oil removal device. More specifically, the present invention relates to an oil draining device for a turbine shaft that constitutes a turbocharger of an automobile engine, for example.

  Generally, an exhaust turbine supercharger (turbocharger) in which an exhaust turbine and a compressor are coaxially connected by a turbine shaft is frequently used in an automobile engine. And since the turbine shaft of a turbocharger rotates at high speed, the bearing which rotatably supports such a turbine shaft needs to be sufficiently lubricated with oil.

  On the other hand, a part of the lubricating oil supplied to the turbine side (turbine rotor side) bearing that rotatably supports the turbine shaft leaks to the turbine side of the turbocharger, and is exhausted through the turbine shaft to rotate the turbine rotor. It may be mixed in the gas. For this reason, the device which excludes the lubricating oil which goes to a turbine side through a turbine shaft before reaching a turbine rotor is required. As a technique for removing the lubricating oil transmitted through the turbine shaft, for example, there is a technique disclosed in Patent Document 1 below.

  2. Description of the Related Art Conventionally, a technique related to an oil removing device for a rotating shaft intended to remove oil attached to a shaft of a rotating machine such as a turbine has been disclosed (see, for example, Patent Document 1). The oil removing device for the rotating shaft is held in a non-contact manner with respect to the rotating shaft so as to surround the convex portion provided around the rotating shaft, and the oil removing device for the rotating shaft having a concave portion formed in a portion facing the protruding portion. In the apparatus, the oil draining apparatus is characterized in that protrusions directed outwardly are provided on both side surfaces in the recess so as to face each other while holding a gap. With this configuration, it is said that the lubricating oil shaken off by the rotating shaft can be captured by the concave portion where the protrusion is formed, and the lubricating oil is not leaked to the outside.

Japanese Utility Model Publication No. 62-60768

  However, in the oil draining device described in Patent Document 1, the lubricating oil that has been swung away from the rotating shaft toward the concave portion having the opposing protrusions on both inner side surfaces passes through the gap between at least one opposing protrusion. Otherwise, it will not be captured in the recess. If a large amount of lubricating oil is rebounded by the protrusion without passing through the gap, the opposing protrusion simply acts to narrow the oil draining space of the recess. Here, it is necessary to widen the gap in order to make it easier for the lubricating oil to pass through the gap between the opposing protrusions. On the other hand, it is necessary to narrow the gap in order to increase the capture efficiency and the capture amount of the lubricating oil. That is, it is difficult to determine how much the gap size between the opposing protrusions is set, and the presence of the opposing protrusions acts in a direction that reduces the lubricating oil removal performance. In addition, it is not easy to manufacture such a protrusion in the recess, and the manufacturing cost is high.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an oil draining device for a turbine shaft that can improve the removal performance of lubricating oil shaken off by centrifugal force caused by the rotation of the turbine shaft. Is to provide.

Means and effects for solving the problems

  The turbine shaft oil draining device according to the present invention relates to a turbine shaft oil draining device suitable for preventing oil outflow to the turbine rotor. The turbine shaft oil removal device according to the present invention has several features as described below in order to achieve the above object. That is, the turbine shaft oil draining device of the present invention includes the following features alone or in combination.

  In order to achieve the above object, a first feature of a turbine shaft oil draining device according to the present invention is a turbine shaft, an oil drain portion provided coaxially with the turbine shaft, the turbine shaft, and the oil drainer. An oil draining device for a turbine shaft having a housing for housing a portion, wherein a peripheral wall at a position facing the oil draining portion of an inner wall of the housing is covered with an oil-repellent film.

  According to this configuration, the lubricating oil swung in the radial direction from the oil drainage portion by centrifugal force due to the rotation of the turbine shaft collides with the peripheral wall of the housing that is provided at a position facing the oil drainage portion and covered with the oil-repellent film. To do. The lubricating oil that has collided with the peripheral wall flows along the peripheral wall without adhering to the wall surface of the peripheral wall by the oil-repellent film, and is collected in the lower part in the housing. Lubricating oil that has collided with the ceiling of the peripheral wall as in the prior art is prevented from falling down and dropping onto the turbine shaft 2. In other words, the oil-repellent film formed on the peripheral wall of the inner wall of the housing facing the oil drainage portion can improve the performance of removing the lubricating oil that has been shaken off by the rotation of the turbine shaft.

  A second feature of the oil draining device for a turbine shaft according to the present invention is a turbine rotor connected to one end portion of the turbine shaft, wherein the peripheral wall is formed in a concave shape, and the peripheral wall The cross-sectional shape orthogonal to the axial direction of the turbine shaft is formed in a circular shape whose diameter decreases as it goes away from the turbine rotor side, or a circular shape whose diameter decreases as it goes toward the turbine rotor side.

  According to this configuration, an oil draining space can be secured between the turbine shaft and the housing by making the peripheral wall at the position facing the oil draining portion of the inner wall of the housing concave.

  Further, when the rotational speed of the turbine shaft is relatively low or the viscosity of the lubricating oil is high, the momentum of the lubricating oil shaken off in the radial direction from the oil drain is relatively small. Therefore, the force acting on the lubricating oil that has collided with the peripheral wall of the upper part of the housing may have a higher gravity than the centrifugal force. In this case, as a first form, when the cross-sectional shape perpendicular to the axial direction of the turbine shaft in the peripheral wall is formed into a circular shape whose diameter decreases with increasing distance from the turbine rotor side, the lubricating oil collides with the peripheral wall at the top of the housing and then the peripheral wall Along the direction of rotation of the turbine shaft and away from the turbine rotor side. And it collect | recovers by the lower part in a housing. A part of the lubricating oil may fall on the turbine shaft or the like, but it can be removed again by the oil drain, so that it does not reach the turbine rotor.

  Further, when the rotational speed of the turbine shaft is high or when the viscosity of the lubricating oil is low, the momentum of the lubricating oil shaken off in the radial direction from the oil drain is relatively large. Therefore, the force acting on the lubricating oil that has collided with the peripheral wall of the upper part of the housing may be more effective than the centrifugal force. In this case, as a second form, when the cross-sectional shape orthogonal to the axial direction of the turbine shaft in the peripheral wall is made circular so that the diameter decreases toward the turbine rotor side, the lubricating oil collides with the peripheral wall at the top of the housing and then the peripheral wall Along the direction of the rotation of the turbine shaft and away from the turbine rotor side. And it collect | recovers by the lower part in a housing. A part of the lubricating oil may fall on the turbine shaft or the like, but it can be removed again by the oil drain, so that it does not reach the turbine rotor. The first form or the second form is appropriately selected in consideration of the rotational speed of the turbine shaft, the viscosity of the lubricating oil, and the like.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The turbine shaft oil removing device according to the present invention includes an exhaust turbine used in an exhaust turbine supercharger (turbocharger) of an automobile engine, a turbine of a gas turbine engine used as an engine for an aircraft, an engine for a pump, and the like. This is an oil draining device for a turbine shaft that can be used in a turbine for various applications.

(First embodiment)
First, based on FIGS. 1 and 2, a turbine shaft oil draining device according to a first embodiment of the present invention will be described in detail. FIG. 1 is a schematic diagram showing a turbocharger 1 provided with a turbine shaft oil draining device according to a first embodiment of the present invention. FIG. 2 is a schematic view of the bowl-shaped member 6 shown in FIG.

  As shown in FIG. 1, a turbocharger 1 provided with a turbine shaft oil drain device according to a first embodiment of the present invention includes a turbine shaft 2 and a cylindrical oil drain provided coaxially with the turbine shaft 2. Portion 9, housing 5 that accommodates turbine shaft 2 and oil drain 9, turbine rotor 3 that is coaxially connected to turbine shaft 2 at one end of turbine shaft 2, and the other end of turbine shaft 2 A compressor rotor (not shown) connected coaxially with the turbine shaft 2 and a bearing 4 fitted into the turbine shaft 2 and disposed on the other side of the turbine shaft 2 are provided.

  The turbine shaft 2 includes a lubricating oil supply unit 12 between the turbine rotor 3 and the bearing 4 in the order of an oil drain 9 and a cylindrical spacer 11 with a seal ring 7 attached to the outer periphery from the bearing 4 side. A member for preventing the lubricating oil supplied to the bearing 4 from flowing out to the turbine rotor 3 side is arranged. The portion where the seal ring 7 is disposed is a final seal portion for preventing the lubricating oil from the bearing 4 side from flowing out into a housing (not shown) in which the turbine rotor 3 is accommodated. The seal ring 7 may be attached to the inner wall side of the housing 5.

  In addition, the peripheral wall 10 at a position facing the oil drain 9 on the inner wall of the housing 5 is formed in a concave shape and covered with the oil-repellent film 8. The oil-repellent film 8 is made of an oil-repellent material such as a fluorine-based resin. Moreover, it is relatively easy to coat the peripheral wall 10 of the housing 5 with the oil-repellent material. Furthermore, the cross-sectional shape orthogonal to the axial direction X of the turbine shaft 2 in the peripheral wall 10 is formed in a circular shape whose diameter decreases with increasing distance from the turbine rotor 3 side, and the peripheral wall 10 is inclined toward the center direction of the turbine shaft 2. It is a slope. Further, at both ends in the axial direction X of the peripheral wall 10, a flange-like member 6 on the bearing 4 side and a flange-like member 13 on the turbine rotor 3 side cover the end of the peripheral wall 10 and the oil draining portion 9. Between. Here, FIG. 2 (a) is a side view of the bowl-shaped members (6, 13), and FIG. 2 (b) is a front view of the bowl-shaped members (6, 13). As shown in FIG. 2, the hook-shaped members (6, 13) are inverted U-shaped hook-shaped members whose cross sections are arc-shaped grooves. The lower parts of the bowl-shaped members (6, 13) are fixed to the inner wall of the housing 5 or the like.

  The cylindrical oil drain 9 is cut out in a circular arc around the center in the axial direction X, the diameter of the end on the bearing 4 side is larger than the diameter of the turbine shaft 2, and the diameter of the end on the turbine rotor 3 side. Is larger than the diameter of the spacer 11. Oil is easily cut off at the stepped portion between the end portion on the bearing 4 side and the turbine shaft 2, the central portion cut out in an arc shape, and the stepped portion between the end portion on the turbine rotor 3 side and the spacer 11. The oil drain 9 is a member attached coaxially to the turbine shaft 2, but may be formed integrally with the turbine shaft. In addition, the shape of the oil drainage part 9 is not restricted to this. Further, the oil draining portion 9 is not limited to one as in the present embodiment, and a plurality of oil draining portions 9 may be provided between the turbine rotor 3 and the bearing 4. Similarly, a plurality of concave peripheral walls 10 may be provided between the turbine rotor 3 and the bearing 4 so as to face the oil draining portion 9, or a plurality of concave peripheral walls 10 may be provided at positions facing the plurality of oil draining portions 9. One may be provided for the oil drainer 9.

  Next, a mode in which the lubricating oil leaking from the bearing 4 is excluded will be described. Some of the lubricating oil leaked from the bearing 4 moves to the turbine rotor 3 side through the turbine shaft 2, and some of the lubricating oil is swung away in the radial direction immediately after leaving the bearing 4 by the rotation of the turbine shaft 2. is there. First, the lubricating oil that moves along the turbine shaft 2 to the turbine rotor 3 side will be described. A part of the lubricating oil supplied to the bearing 4 from the lubricating oil supply unit 12 and reaches the oil drainage part 9 through the turbine shaft 2 from the bearing 4 side is blocked by the oil drainage part 9 from moving to the turbine rotor 3 side. Then, it falls down in the housing 5 and is collected. In addition, some of the lubricating oil that has reached the oil draining portion 9 is swung away from the oil draining portion 9 in the radial direction by centrifugal force generated by the rotation of the turbine shaft 2. The lubricating oil shaken off in the radial direction from the oil drain 9 collides with the peripheral wall 10 of the concave housing 5 provided at a position facing the oil drain 9 and covered with the oil-repellent film 8. The lubricating oil that has collided with the peripheral wall 10 flows along the peripheral wall 10 without being attached to the wall surface of the peripheral wall 10 by the oil-repellent film 8 and is collected in the lower part of the housing 5. It is possible to prevent the lubricating oil that has collided with the ceiling portion of the peripheral wall 10 from falling down and dropping onto the turbine shaft 2 as in the prior art. In other words, the oil-repellent film 8 formed on the peripheral wall 10 at a position facing the oil draining portion 9 in the inner wall of the housing 5 improves the performance of removing the lubricating oil shaken off by the rotation of the turbine shaft 2 as compared with the prior art. be able to.

  Here, when the rotational speed of the turbine shaft 2 is relatively low or the viscosity of the lubricating oil is high, the momentum of the lubricating oil shaken off in the radial direction from the oil drain 9 becomes relatively small, and the upper portion of the housing 5 The force acting on the lubricating oil that has collided with the peripheral wall 10 may be more gravitational than the centrifugal force. In this case, the lubricating oil collides with the peripheral wall 10 at the top of the housing 5 and then flows down along the slope of the peripheral wall 10 in the direction of rotation of the turbine shaft 2 or away from the turbine rotor 3 side. Lubricating oil that flows in the direction away from the turbine rotor 3 side falls from the end of the peripheral wall 10 on the bearing 4 side onto the bowl-shaped member 6, travels along the bowl-shaped member 6, and is collected in the lower part of the housing 5. On the other hand, the lubricating oil that has fallen onto the bowl-shaped member 13 from the end of the peripheral wall 10 on the turbine rotor 3 side is also collected in the lower part of the housing 5 through the bowl-shaped member 13.

  Next, the lubricating oil that is swung away in the radial direction immediately after leaving the bearing 4 due to the rotation of the turbine shaft 2 will be described. The lubricating oil supplied from the lubricating oil supply unit 12 to the bearing 4 and swung away in the radial direction immediately after leaving the bearing 4 is in front of the peripheral wall 10 where the oil-repellent film 8 is formed (on the bearing 4 side from the peripheral wall 10). There is also lubricating oil that falls after colliding with the inner wall of the housing 5 and is dropped below the housing 5, or falls on the turbine shaft 2 and travels along the turbine shaft 2 toward the oil drain 9. There is also lubricating oil that directly collides with the peripheral wall 10 on which the oleaginous film 8 is formed. The lubricating oil that has collided with the peripheral wall 10 flows along the peripheral wall 10 without being attached to the wall surface of the peripheral wall 10 by the oil-repellent film 8 and is collected in the lower part of the housing 5. That is, according to the oil removing device for a turbine shaft of the present invention, the lubricating oil shaken off from the turbine shaft 2 at a position not facing the peripheral wall 10 can also be recovered efficiently.

  Note that it is not always necessary to provide the bowl-shaped members (6, 13). This is because the oil-repellent film 8 formed on the peripheral wall 10 causes most of the lubricating oil that has collided with the peripheral wall 10 to be collected in the lower part of the housing 5 along the peripheral wall 10 without adhering to the peripheral wall 10. Further, even if the oil drops on the turbine shaft 2 on the bearing 4 side or the like, the lubricating oil can be removed again by the oil draining portion 9, so that it does not reach the turbine rotor 3. Moreover, since there is nothing in the recessed part of the housing 5 which sacrifices the oil draining space like the protrusion which the oil draining apparatus of patent document 1 opposes, it is easy to ensure the oil draining space S.

(Second Embodiment)
Next, a turbine shaft oil draining device according to a second embodiment of the present invention will be described in detail with reference to FIG. FIG. 3 is a schematic view showing a turbocharger 51 provided with a turbine shaft oil draining device according to a second embodiment of the present invention. In the description of the present embodiment, the same components as those of the turbocharger 1 shown in FIG. 1 according to the first embodiment of the present invention are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 3, in the turbocharger 51 provided with the turbine shaft oil draining device according to the second embodiment of the present invention, the cross-sectional shape of the peripheral wall 10 perpendicular to the axial direction X of the turbine shaft 2 is the turbine rotor 3. It is formed in a circular shape with a diameter that decreases toward the side, and the peripheral wall 10 is an inclined surface that is inclined toward the center of the turbine shaft 2 toward the turbine rotor 3 side.

  Here, when the rotational speed of the turbine shaft 2 is high or the viscosity of the lubricating oil is low, the momentum of the lubricating oil shaken off in the radial direction from the oil drain 9 becomes relatively large, and the peripheral wall 10 at the top of the housing 5 In some cases, the centrifugal force is superior to gravity as the force acting on the lubricating oil that collides with. In this case, the lubricant oil collides with the peripheral wall 10 at the top of the housing 5 and then flows so as to rise in the direction of rotation of the turbine shaft 2 or away from the turbine rotor 3 side along the slope of the peripheral wall 10. Lubricating oil that flows in the direction away from the turbine rotor 3 side falls from the end of the peripheral wall 10 on the bearing 4 side onto the bowl-shaped member 6, travels along the bowl-shaped member 6, and is collected in the lower part of the housing 5. On the other hand, the lubricating oil that has fallen onto the bowl-shaped member 13 from the end of the peripheral wall 10 on the turbine rotor 3 side is also collected in the lower part of the housing 5 through the bowl-shaped member 13. Note that it is not always necessary to provide the bowl-shaped members (6, 13). Whether the shape of the peripheral wall 10 is as in the first embodiment or the second embodiment is appropriately selected in consideration of the rotational speed of the turbine shaft 2 and the viscosity of the lubricating oil. Is.

(Third embodiment)
Next, a turbine shaft oil draining device according to a third embodiment of the present invention will be described in detail with reference to FIG. FIG. 4 is a schematic view showing a turbocharger 52 provided with a turbine shaft oil draining device according to a third embodiment of the present invention. In the description of the present embodiment, the same components as those of the turbocharger 1 shown in FIG. 1 according to the first embodiment of the present invention are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 4, in the turbocharger 52 provided with the turbine shaft oil draining device according to the third embodiment of the present invention, the cross-sectional shape of the peripheral wall 10 perpendicular to the axial direction X of the turbine shaft 2 is The diameter of the circumferential wall 10 is reduced toward the center of the axial direction X, and the peripheral wall 10 is an inclined surface that is inclined toward the central direction of the turbine shaft 2 toward the central part of the axial direction X of the peripheral wall 10. And the flange-shaped member 14 is provided between the surrounding wall 10 and the oil drain part 9 so as to oppose the convex part of the axial direction X center part of the surrounding wall 10 formed in this way. The hook-shaped member 14 is a member similar to the hook-shaped members (6, 13) described in the first and second embodiments.

  Lubricating oil shaken off in the radial direction from the oil draining part 9 collides with the peripheral wall 10 at the upper part of the housing 5 and then flows down along the slope of the peripheral wall 10 toward the rotational direction of the turbine shaft 2 and the central part of the peripheral wall 10. Go. Lubricating oil that has flowed toward the central portion of the peripheral wall 10 falls from the convex portion formed in the central portion in the axial direction X of the peripheral wall 10 onto the hook-shaped member 14, travels along the hook-shaped member 14, and is the lower part in the housing 5. To be recovered. In addition, you may provide a hook-shaped member in the both ends of the surrounding wall 10 like 1st, 2nd embodiment. However, it is not always necessary to provide the hook-shaped members (6, 13, 14). The shape of the peripheral wall 10 is appropriately selected in consideration of the rotational speed of the turbine shaft 2, the viscosity of the lubricating oil, and the like in any of the first, second, and third embodiments. Is.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. .

  For example, the shape of the concave peripheral wall 10 may be an arc shape as in the past in a cross-sectional view along the axial direction X, or may be a polygonal shape such as a rectangular shape with the center side of the turbine shaft 2 open.

It is a mimetic diagram showing a turbocharger provided with a turbine shaft oil drain device concerning a 1st embodiment of the present invention. It is a schematic diagram of the bowl-shaped member shown in FIG. It is a schematic diagram which shows the turbocharger which provided the oil draining device of the turbine shaft which concerns on 2nd Embodiment of this invention. It is a schematic diagram which shows the turbocharger which provided the oil draining device of the turbine shaft which concerns on 3rd Embodiment of this invention.

Explanation of symbols

1: turbocharger 2: turbine shaft 3: turbine rotor 5: housing 6: bowl-shaped member 8: soot oil film 9: oil drain 10: peripheral wall X: axial direction

Claims (2)

An oil draining device for a turbine shaft having a turbine shaft, an oil drain portion provided coaxially with the turbine shaft, and a housing for housing the turbine shaft and the oil drain portion,
An oil draining device for a turbine shaft, wherein a peripheral wall at a position facing the oil draining portion of the inner wall of the housing is covered with an oil-repellent film. A turbine rotor connected to one end of the turbine shaft;
The peripheral wall is formed in a concave shape,
The cross-sectional shape perpendicular to the axial direction of the turbine shaft in the peripheral wall is formed in a circular shape whose diameter decreases as it moves away from the turbine rotor side, or a circular shape whose diameter decreases as it goes toward the turbine rotor side. The oil removal device for a turbine shaft according to claim 1, wherein

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