KR20190106719A - Supercharger - Google Patents

Abstract

Provided in the present invention is a supercharger, which can prevent inclination during rotation of a rotating shaft for a long period, and can prevent the rotating shaft or a thrust member from coming in contact with a thrust bearing. To this end, the supercharger comprises: a rotating shaft; a compressor wheel formed at one end of the rotating shaft; a thrust member fittingly inserted into the rotating shaft; a thrust bearing arranged to be adjacent to the thrust member in an axial line direction of the rotating shaft, and supporting the rotating shaft in a thrust direction; a housing storing the thrust member and the thrust bearing. Here, a clearance is formed between an outer circumferential surface of the thrust member and the housing in a direction crossing at right angles in an axial line direction. The clearance is configured such that oil may flow thereinto. Therefore, when the rotating shaft and the thrust member are rotated, the oil flowed into the clearance generates an oil film pressure pressurizing in a direction crossing at right angles to the thrust member in an axial line direction.

Description

Supercharger {SUPERCHARGER}

The present disclosure relates to a supercharger having a thrust bearing for supporting a rotation shaft in the thrust direction.

The supercharger provided with a rotating shaft, the thrust collar attached to the outer periphery of the rotating shaft, and the thrust bearing which supports the thrust load which acts on a rotating shaft through the thrust collar is known widely (for example, patent document 1).

In recent years, with the demand for downsizing of the engine, there has been a demand for a larger capacity of the supercharger mounted on the engine. When the supercharger is a large capacity, the thrust load acting on the rotary shaft of the supercharger increases, so that the inclination of the shaft center during rotation of the rotary shaft increases. When the inclination of the shaft center of the rotary shaft becomes larger, there is a possibility that one-sided contact occurs between the thrust collar and the thrust bearing, and a sudden temperature rise or sticking due to the one-sided contact with the thrust bearing and the thrust collar is increased.

The supercharger of patent document 1 provides the inner peripheral pad which can elastically deform in the cross section of the thrust collar side of a thrust bearing, and elastically deforms so that an inner peripheral pad may fall from a thrust bearing when a rotating shaft and a thrust collar are inclined, It is described that an oil film thickness for supporting a thrust load is secured between the inner circumferential pad and the thrust collar to exert a thrust load burden capability on the inner circumferential pad.

Japanese Unexamined Patent Publication No. 2003-232340

The supercharger described in Patent Document 1 has a fear that the inner circumferential pad of the thrust bearing may be broken by the repetition of deformation and restoration in the elastic deformation described above. In addition, due to the decrease in the elastic force due to fatigue of the inner circumferential pad, the oil film thickness between the thrust bearing and the thrust collar cannot be secured, and there is a possibility that a sudden temperature rise or sticking occurs in the thrust bearing or the thrust collar.

In view of the above-described circumstances, an object of at least one embodiment of the present invention can suppress the inclination during the rotation of the rotary shaft for a long time and prevent the rotary shaft or the thrust member from contacting the thrust bearing. It is to provide supercharger which we can do.

(1) The supercharger which concerns on at least one Embodiment of this invention,

Rotation axis,

A compressor wheel formed at one end of the rotating shaft;

A thrust member fitted to the rotary shaft;

A thrust bearing disposed adjacent to the thrust member in the axial direction of the rotary shaft and supporting the rotary shaft in the thrust direction;

A housing accommodating the thrust member and the thrust bearing;

A clearance is formed between an outer peripheral surface of the thrust member in the direction orthogonal to the axial direction and the housing in at least a part of the axial direction and the circumferential direction of the rotational shaft, and the clearance is configured such that oil flows into the clearance.

When the rotating shaft and the thrust member rotate, the oil flowing into the clearance generates an oil film pressure that presses the thrust member along a direction orthogonal to the axial direction.

According to the structure of said (1), the supercharger is arrange | positioned adjacent to a thrust member in the axial direction of a rotating shaft, the compressor wheel provided in the end of a rotating shaft, the thrust member fitted to a rotating shaft, and the axial direction of a rotating shaft, And a housing for housing the thrust bearing and the thrust bearing for supporting the thrust bearing in the thrust direction. A clearance is formed between the outer peripheral surface of the thrust member in the direction orthogonal to the axial direction of the rotation shaft and the housing in at least a part of the axial direction and the circumferential direction of the rotation shaft, and oil is flowed into the clearance. And when the rotating shaft and thrust member rotate, it is comprised so that the oil which flowed into clearance may generate | generate the oil film pressure which presses along the direction orthogonal to a thrust member in an axial direction.

For this reason, the oil flowing into the clearance forms a lubricating film when the rotating shaft and the thrust member rotate, and generates an oil film pressure that pushes the thrust member toward the axis along the direction orthogonal to the axial direction. Inclination of the axis can be suppressed. Therefore, it is also possible to prevent the rotating shaft and the thrust member from contacting the thrust bearing. By preventing contact between the rotating shaft, the thrust member, and the thrust bearing, damage due to abrasion of the rotating shaft, the thrust member, and the thrust bearing can be suppressed, and the supercharger can be used for a long time.

(2) In some embodiments, in the structure of said (1),

When the magnitude | size of the said clearance is C and the outer dimension of the thrust member is D, the clearance in at least one part satisfies the condition of clearance ratio C / D of 5/1000 <= C / D <10/1000 do.

According to the configuration of (2), since the clearance in at least a part satisfies the above-described conditions, the oil flowing in the clearance can exhibit an appropriate oil film pressure. Moreover, when clearance ratio is C / D <5/1000, there exists a possibility that a rotating shaft and a thrust member may contact a thrust bearing by the inclination at the time of rotation of a rotating shaft. Moreover, when clearance ratio is 10/1000 <C / D, there exists a possibility that oil may not exhibit sufficient oil film pressure.

(3) In some embodiments, in the structure of said (1) or (2),

The clearance is formed larger than at least a portion of the thrust bearing side in the axial direction relative to the side away from the thrust bearing.

According to the configuration of (3), the oil can easily flow from the thrust bearing side of the clearance, and the oil is difficult to flow from the side away from the thrust bearing of the clearance. For this reason, the oil film pressure which presses the thrust member by oil along the direction orthogonal to an axial direction can be increased.

(4) In some embodiments, in the structure of said (3),

An inner dimension of the portion forming the clearance of the housing is larger than at least a portion of the thrust bearing side in the axial direction relative to the side away from the thrust bearing.

According to the configuration of (4), the oil can easily flow from the thrust bearing side of the clearance, and the oil is difficult to flow from the side away from the thrust bearing of the clearance. For this reason, the oil film pressure which presses the thrust member by oil along the direction orthogonal to an axial direction can be increased.

(5) In some embodiments, in the structure of said (3) or (4),

An outer dimension of the thrust member is smaller than at least a portion of the thrust bearing side in the axial direction relative to the side away from the thrust bearing.

According to the configuration of (5), oil can easily flow from the thrust bearing side of the clearance, and oil is difficult to flow from the side away from the thrust bearing of the clearance. For this reason, the oil film pressure which presses the thrust member by oil along the direction orthogonal to an axial direction can be increased.

(6) In some embodiments, in the structure of said (3),

The thrust member has a chamfered surface at at least a part of an end portion on the thrust bearing side in the axial direction.

According to the configuration of (6), since at least a part of the end of the thrust bearing side in the axial direction of the thrust member has a chamfered surface, oil can easily flow from the thrust bearing side of the clearance, and the oil It is difficult to flow out from the side away from the thrust bearing of this clearance. For this reason, the oil film pressure which presses the thrust member by oil along the direction orthogonal to an axial direction can be increased. The chamfered surface can be easily formed by cutting or the like.

(7) In some embodiments, in the structure of said (1)-(6),

The housing is configured such that an enlarged diameter portion in which the clearance is partially enlarged is arranged evenly in the circumferential direction of the rotation shaft.

According to the configuration of (7), by forming the enlarged diameter portion where the clearance is partially enlarged by the housing and the portion having a smaller clearance than the enlarged diameter portion, oil can easily flow into the enlarged diameter portion of the clearance, The clearance is less likely to flow out of the smaller portion than the enlarged diameter portion of the clearance. For this reason, since the peak part of oil film pressure can be formed in the several point in the circumferential direction, the oil film pressure which presses the thrust member by oil along the direction orthogonal to an axial direction can be increased.

Particularly, when at least part of the clearance on the thrust bearing side in the axial direction is formed larger than the clearance on the side away from the thrust bearing, the oil film at the peak of the oil film pressure formed at a plurality of points in the circumferential direction Can increase the pressure.

(8) In some embodiments, in the structure of said (1)-(7),

The housing was formed with a non-contact seal including a plurality of recesses on a surface of the compressor wheel that faces the rear surface of the compressor wheel.

According to the configuration of (8), the compressed gas that flows between the back surface of the compressor wheel and the surface of the housing facing the back surface by the non-contact seal including the plurality of recesses, when the rotary shaft and the compressor wheel rotated. Since a lubricating film is formed and the gas film pressure which presses a compressor wheel along an axial direction is produced, the inclination of the axial line at the time of rotation of a rotating shaft can be suppressed. Thus, the compressor wheel can be prevented from contacting the housing. By preventing contact between the compressor wheel and the housing, damage caused by abrasion of the compressor wheel and the housing can be suppressed, and the supercharger can be used for a long time.

(9) In some embodiments, in the structure of said (1)-(8),

Further provided is a turbine wheel formed on the other end of the rotary shaft.

According to the structure of said (9), a supercharger is a turbocharger provided with a compressor wheel and a turbine wheel. In the turbocharger, the pressure of a gas such as compressed air, which acts on the compressor wheel, is lower than the pressure of a gas such as exhaust gas, which acts on the turbine wheel. It will move around much larger than the wheel. Even in the rotary shaft of such a turbocharger, as mentioned above, the oil which flowed into the clearance acts the oil film pressure on the thrust member, and the inclination at the time of rotation of the rotary shaft can be suppressed.

According to at least one embodiment of the present invention, it is possible to suppress the inclination at the time of rotation of the rotating shaft and to provide a supercharger which can prevent the rotating shaft and the thrust member from contacting the thrust bearing.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating the whole structure of the supercharger which concerns on one Embodiment of this invention.
FIG. 2 is a schematic cross-sectional view showing an enlarged portion of the supercharger shown in FIG. 1. FIG.
3 is a schematic cross-sectional view along the axial direction of a rotating shaft schematically showing the main components inside the housing in the supercharger according to the embodiment of the present invention.
4 is a graph schematically showing a relationship between a clearance ratio and an oil film pressure in a supercharger according to an embodiment of the present invention.
FIG. 5: is schematic sectional drawing along the axial direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention.
FIG. 6: is schematic sectional drawing along the axial direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention.
FIG. 7: is schematic sectional drawing along the axial direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention.
FIG. 8: is schematic sectional drawing along the circumferential direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention.
9 is a schematic cross-sectional view along a circumferential direction of a rotating shaft schematically showing the main components inside the housing in the supercharger according to another embodiment of the present invention.
FIG. 10: is schematic sectional drawing along the axial direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention.
FIG. 11 is a diagram for explaining the supercharger according to another embodiment of the present invention, which is a schematic cross-sectional view along the axial direction of a rotating shaft schematically showing a compressor wheel and a housing. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, some embodiment of this invention is described with reference to an accompanying drawing. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described as embodiments or shown in the drawings are not merely intended to limit the scope of the present invention thereto, but are merely illustrative examples.

For example, an expression representing a relative or absolute arrangement of "in one direction", "in which direction", "parallel", "orthogonal", "center", "concentric", or "coaxial" is strictly such. Not only the arrangement is shown, but also the state in which the displacement or relative displacement is achieved with an angle or distance of the degree to which the same function is obtained.

For example, an expression indicating that objects such as "equal", "equal", and "homogeneous" are equal states not only indicates a strictly equivalent state but also a difference in tolerance or degree to which the same function is obtained. It shall also show the state which it is doing.

For example, the expression representing a shape such as a rectangular shape or a cylindrical shape indicates not only a shape such as a rectangular shape or a cylindrical shape in a geometrically precise sense, but also includes an uneven part, a chamfer part, and the like within a range in which the same effect is obtained. It is also assumed that the shape to be described.

On the other hand, the expression "having", "having", "equipment", "include", or "having" one component is not an exclusive expression excluding the existence of other components.

In addition, about the same structure, the same code | symbol may be attached | subjected and description may be abbreviate | omitted.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating the whole structure of the supercharger which concerns on one Embodiment of this invention. FIG. 2 is a schematic cross-sectional view showing an enlarged portion of the supercharger shown in FIG. 1. FIG. 3 is a schematic cross-sectional view along the axial direction of a rotating shaft schematically showing the main components inside the housing in the supercharger according to the embodiment of the present invention.

The supercharger 1 which concerns on some embodiment shown to FIGS. 1-11 is a turbocharger for ships, and as shown to FIGS. 1 and 2, the rotating shaft extended along an axial direction (left-right direction among FIG. 1, 2) ( 2), the compressor wheel 11 formed in the one end of the axial direction of the rotating shaft 2, and the turbine wheel 12 formed in the other end of the axial direction of the rotating shaft 2 are provided. And the turbocharger 1 is equipped with the thrust member 3 (thrust collar) fitted to the rotating shaft 2, and the thrust member 3 in the axial direction of the rotating shaft 2, as shown to FIG. It is further provided with the thrust bearing 4 which is arrange | positioned adjacent to and supports the rotating shaft 2 in the thrust direction, and the housing 5 which accommodates the thrust member 3 and the thrust bearing 4.

As shown in FIG. 2, the housing 5 of the supercharger 1 includes a compressor housing 5A that houses the compressor wheel 11, a turbine housing 5B that houses the turbine wheel 12, and a thrust bearing. The bearing housing 5C which accommodates (4) is included. The bearing housing 5C is arrange | positioned between the compressor housing 5A and the turbine housing 5B in the axial direction of the rotating shaft 2, as shown in FIG. 2, for example, the screw connection etc. which used the bolt. It is fixed to the compressor housing 5A and the turbine housing 5B by this. In addition, as shown in FIG. 2, the bearing housing 5C has the thrust member 3 and the thrust bearing 4 in the radial direction of the rotary shaft 2 (the direction orthogonal to the axial direction of the rotary shaft 2). Housed in

Moreover, as shown in FIG. 2, the supercharger 1 is further provided with a thrust bearing 13 on the side opposite to the thrust bearing 4 with respect to the thrust member 3 in the axial direction of the rotation shaft 2. Doing. Similar to the thrust bearing 4, the thrust bearing 13 is disposed adjacent to the thrust member 3 in the axial direction of the rotation shaft 2, and supports the rotation shaft 2 in the thrust direction.

In addition, as shown in FIG. 2, the supercharger 1 is housed in the radially inner side of the bearing housing 5C and supports a pair of journal bearings 14 and 15 rotatably supporting the rotation shaft 2. Furthermore, it is equipped. As shown in FIG. 2, the journal bearing 14 is arrange | positioned at the compressor wheel 11 side in the axial direction of the rotating shaft 2, and the journal bearing 15 is in the axial direction of the rotating shaft 2 as shown in FIG. It is arrange | positioned at the turbine wheel 12 side.

As shown in FIG. 3, the thrust member 3 has an outer circumferential surface 31 and an inner circumferential surface 32, and the inner circumferential surface 32 is fitted to the outer circumferential surface 21 of the rotational shaft 2 to the rotating shaft 2. It is fixed. For this reason, the thrust member 3 is made to rotate in synchronization with the rotation of the rotating shaft 2. As shown in FIG. 3, the thrust member 3 includes a thrust member 3A formed in a cylindrical shape having a constant outer diameter dimension.

As shown in FIG. 3, the thrust bearing 4 is formed in a circular shape having an outer circumferential surface 41 and an inner circumferential surface 42, and the outer circumferential surface 41 is fitted to the housing 5 to be fixed to the housing 5. In addition, the rotation shaft 2 is loosely inserted through the inner circumferential surface 42.

As shown in FIG. 3, the housing 5 includes a thrust member accommodating portion 51 that accommodates the thrust member 3 inside the radial direction of the rotation shaft 2, and a thrust bearing that fits the thrust bearing 4. At least the fitting portion 52 is included. And clearance 6 is formed in at least one part of the axial direction and the circumferential direction of the rotating shaft 2 between the outer peripheral surface 41 of the thrust member 3 and the housing 5 in the radial direction of the rotating shaft 2. It is.

The oil is flowed into the clearance 6, and the oil which flowed into the clearance 6 is orthogonal to the thrust member 3 in the axial direction when the rotation shaft 2 and the thrust member 3 rotate. It is comprised so that the oil film pressure which presses along a direction to make may be generated. Specifically, it is comprised so that oil may be supplied between the inner peripheral surface 42 of the thrust bearing 4, and the outer peripheral surface 21 of the rotating shaft 2 as shown in FIG. The oil supplied between the inner circumferential surface 42 of the thrust bearing 4 and the outer circumferential surface 21 of the rotary shaft 2 is the end face 43 on the side of the thrust member 3 in the axial direction of the thrust bearing 4. And the first end face 33 facing the end face 43 of the thrust member 3 to flow into the clearance 6. The oil which flowed into the clearance 6 produces | generates the oil film pressure which presses the thrust member 3 along radial direction, when the rotating shaft 2 and the thrust member 3 rotate as shown in FIG.

As described above, the supercharger 1 according to some embodiments includes the above-described rotary shaft 2, the above-mentioned compressor wheel 11 formed on one end of the rotary shaft 2, and the rotary shaft 2. The above-mentioned thrust bearing which is fitted to the thrust member 3 mentioned above and the thrust member 3 in the axial direction of the rotating shaft 2, and supports the rotating shaft 2 in the thrust direction. (4) and the housing | casing 5 mentioned above which accommodates the thrust member 3 and the thrust bearing 4 are provided. And the clearance 6 is formed between the outer peripheral surface 31 of the thrust member 3 in the direction orthogonal to the axial direction of the rotating shaft 2, and the housing 5, and oil flows in the clearance 6 It is configured to lift. Moreover, when the rotating shaft 2 and the thrust member 3 rotate, the oil which flowed into the clearance 6 generate | occur | produces the oil film pressure which presses along the direction orthogonal to the thrust member 3 in an axial direction. have.

For this reason, the oil which flowed into the clearance 6 forms a lubrication film when the rotating shaft 2 and the thrust member 3 rotated, as shown in FIG. 3, and orthogonally crosses the thrust member 3 to an axial direction. Since the oil film pressure which presses toward an axis line along a direction is produced, the inclination of the axis line at the time of rotation of the rotating shaft 2 can be suppressed. Therefore, the rotation shaft 2 and the thrust member 3 can be prevented from contacting the thrust bearing 4. By preventing the contact between the rotary shaft 2, the thrust member 3, and the thrust bearing 4, the damage caused by the wear of the rotary shaft 2, the thrust member 3, and the thrust bearing 4 can be suppressed, and the supercharger It is possible to use (1) for a long time.

In some embodiments, as shown in FIG. 3, when the magnitude | size of the clearance 6 mentioned above is C and the outer dimension of the thrust member 3 mentioned above is D, the axial direction of the rotating shaft 2 is carried out. And the clearance 6 in at least a part of the circumferential direction satisfies the condition that the clearance ratio C / D is 5/1000 ≦ C / D ≦ 10/1000. 4 is a graph schematically showing the relationship between the clearance ratio and the oil film pressure in the supercharger according to the embodiment of the present invention. As shown in FIG. 4, when the clearance ratio C / D becomes small, there exists a tendency for the oil film pressure which the oil in clearance 6 exerts to rise. However, when the clearance ratio C / D is too small, the possibility that the rotating shaft 2 or the thrust member 3 contacts the thrust bearing 4 or the press will increase is high. Therefore, when clearance ratio C / D satisfy | fills the conditions mentioned above, the oil which flowed into the clearance 6 can exhibit appropriate oil film pressure. In addition, when the clearance ratio is C / D <5/1000, the rotation shaft 2 and the thrust member 3 may come into contact with the thrust bearing 4 due to the inclination at the time of rotation of the rotation shaft 2. have. Moreover, when clearance ratio is 10/1000 <C / D, as shown in FIG. 4, there exists a possibility that oil may not exhibit sufficient oil film pressure.

5-7 is schematic sectional drawing along the axial direction of the rotating shaft which shows the main component inside the housing in the supercharger which concerns on another embodiment of this invention. As shown in FIGS. 5-7, in some embodiments, the clearance 6 mentioned above is large compared with the side in which the thrust bearing 4 side in the axial direction is separated from the thrust bearing 4. Formed. In this case, oil can flow easily from the thrust bearing 4 side of the clearance 6, and oil is hard to flow from the side away from the thrust bearing 4 of the clearance 6. For this reason, the oil film pressure which presses the thrust member 3 by oil along the direction orthogonal to an axial direction can be increased.

In the embodiment shown in FIG. 5, at least a part of the thrust bearing 4 side in the axial direction has an inner dimension of the portion forming the clearance 6 of the housing 5 described above from the thrust bearing 4. It is formed larger than the separated side. Here, the part which forms the clearance 6 of the housing 5 means the clearance formation part 54 containing the inner side surface 53 which opposes the outer peripheral surface 31 of the thrust member 3. Specifically, in the clearance forming portion 54, as shown in FIG. 5, the tapered surface 55 in which the thickness in the axial direction gradually becomes thinner toward the thrust bearing 4 side in the axial direction is provided. Formed. For this reason, the inner dimension of the clearance formation part 54 is formed large compared with the side in which the thrust bearing 4 side in an axial direction is separated from the thrust bearing 4. In this case, oil can flow easily from the thrust bearing 4 side of the clearance 6, and oil is hard to flow from the side away from the thrust bearing 4 of the clearance 6. For this reason, the oil film pressure which presses the thrust member 3 by oil along the direction orthogonal to an axial direction can be increased.

In embodiment shown in FIG. 6, the outer dimension of the thrust member 3 mentioned above is formed small compared with the side in which the thrust bearing 4 side in the axial direction was separated from the thrust bearing 4. . Specifically, as shown in FIG. 6, the thrust member 3 includes a thrust member 3B formed in a cone shape. The thrust member 3B has the outer diameter dimension in the 1st end surface 33 mentioned above rather than the outer diameter dimension in the 2nd end surface 34 on the opposite side to the 1st end surface 33 in an axial direction. It is formed small. That is, as shown in FIG. 6, the thrust member 3B is provided with the taper surface 35 by which the outer diameter dimension becomes small gradually toward the thrust bearing 4 side in an axial direction. In this case, oil can flow easily from the thrust bearing 4 side of the clearance 6, and oil is hard to flow from the side away from the thrust bearing 4 of the clearance 6. For this reason, the oil film pressure which presses the thrust member 3B by oil along the direction orthogonal to an axial direction can be increased. Moreover, the thrust member 3B is easy to change design and process compared with the housing 5.

In the embodiment shown in FIG. 7, the thrust member 3 described above has a thrust member having a chamfered surface 36 at at least a portion of an end portion of the thrust bearing 4 side in the axial direction of the rotation shaft 2 ( 3C). As shown in FIG. 7, the thrust member 3C is formed in a cylindrical shape, and a chamfered surface 36 is formed at the outer peripheral end of the first end face 33. In the embodiment shown in FIG. 7, the chamfered surface 36 is formed by an R chamfer having an outer contour in an arc shape when viewed from a cross section along the axial direction of the rotational axis 2, but the rotational axis 2. As seen from the cross section along the axial direction of C, the C chamfer may be implemented in which the outline is formed in a straight line. In this case, since at least a part of the end of the thrust bearing 4 side in the axial direction of the thrust member 3C has a chamfered surface 36, the oil is removed from the thrust bearing 4 side of the clearance 6. It can flow easily, and it is difficult for oil to flow out from the side away from the thrust bearing 4 of the clearance 6. For this reason, the oil film pressure which presses the thrust member 3C by oil along the direction orthogonal to an axial direction can be increased. The chamfered surface 36 can be easily formed by cutting or the like.

8 and 9 are schematic cross-sectional views along the circumferential direction of the rotating shaft schematically showing the main components inside the housing in the supercharger according to another embodiment of the present invention. 8 and 9, in some embodiments, the housing 5 described above includes the enlarged diameter portion 62 in which the clearance 6 is partially enlarged in the circumferential direction of the rotation shaft 2 described above. Is arranged to be evenly arranged. Here, the expansion diameter part 62 is arrange | positioned equally that the combined force of the oil film pressure which generate | occur | produces in the clearance 6 at the time of rotation of the rotating shaft 2 does not act as an eccentric load which eccentrically rotates the rotating shaft 2. It means.

Specifically, in the embodiment shown in FIG. 8, the inner side surface 53 of the housing 5 has a recessed portion that is concave so that the contour shape when viewed in cross section toward the radially outer side of the rotation shaft 2 becomes an arc shape ( 56) is formed every 180 °, so that the outline shape as seen from the cross section is formed into an ellipse shape. The clearance 6 formed between the inner surface 53 of the housing 5 and the outer circumferential surface 31 of the thrust member 3 includes two small diameter portions 61 in the circumferential direction of the rotation shaft 2. Two enlarged diameter portions 62 are alternately formed with a larger clearance 6 than the small diameter portion 61. The circles shown by the dotted lines in FIGS. 8 and 9 are formed for convenience of explanation, and the size of the clearance 6 is set to the same size as the small diameter portion 61.

In addition, in the embodiment shown in FIG. 9, the inner side surface 53 of the housing | casing 5 is recessed in the recessed part 56 so that the contour shape when seen from the cross section toward the radial direction outer side of the rotating shaft 2 may become circular arc shape. Is formed every 120 °, so that the contour shape when viewed from the cross section is formed into a triangular shape with rounded corners. The clearance 6 formed between the inner surface 53 of the housing 5 and the outer circumferential surface 31 of the thrust member 3 includes three small diameter portions 61 in the circumferential direction of the rotation shaft 2. Three enlarged diameter portions 62 are alternately formed with a larger clearance 6 than that of the small diameter portion 61.

According to the above structure, oil is formed by forming the enlarged diameter portion 62 in which the clearance 6 is partially enlarged by the housing 5 and the portion having a smaller clearance than the enlarged diameter portion 62 (small diameter portion 61). It is easy to flow into the enlarged diameter part 62 of the clearance 6, and it is hard to flow out from the part (small diameter part 61) whose clearance is smaller than the enlarged diameter part 62 of the clearance 6. . For this reason, since the peak part of oil film pressure can be formed in the several point in the circumferential direction, the oil film pressure which presses the thrust member 3 by oil along the direction orthogonal to the axial direction of the rotating shaft 2 will be increased. Can be. In particular, when at least one clearance 6 on the side of the thrust bearing 4 in the axial direction of the rotation shaft 2 is formed larger than the clearance 6 on the side away from the thrust bearing 4, the perimeter The oil film pressure in the peak part of the oil film pressure formed in the several point in a direction can be raised.

FIG. 10: is schematic sectional drawing along the axial direction of the rotating shaft which shows the principal component inside the housing in the supercharger which concerns on another embodiment of this invention. Some embodiment mentioned above is applicable also to the supercharger 1 provided with the floating disk 7 as shown in FIG. That is, in some embodiments, the supercharger 1 mentioned above is the floating disc 7 loosely inserted through the rotating shaft 2 mentioned above as shown in FIG. The floating disk 7 arrange | positioned between the thrust member 3 and the thrust bearing 4 in the axial direction of the further is provided. In other words, the thrust bearing 4 is arrange | positioned adjacent to the thrust member 3 via the floating disk 7. As shown in FIG. 10, the floating disk 7 is formed in a cylindrical shape having an outer circumferential surface 71 and an inner circumferential surface 72, and is disposed between the outer circumferential surface 71 and the inner surface 53 of the housing 5. While the gap in which oil flows is formed, the rotating shaft 2 is loosely inserted through the inner circumferential surface 72. Even in the supercharger 1 provided with such a floating disk 7, since oil flows into the clearance 6, the oil which flowed into the clearance 6 can exert an oil film pressure with respect to the thrust member 3. .

FIG. 11 is a diagram for explaining the supercharger according to another embodiment of the present invention, which is a schematic cross-sectional view along the axial direction of a rotating shaft schematically showing a compressor wheel and a housing. FIG. As shown in FIG. 11, in some embodiments, the housing 5 mentioned above has the some recessed part 81 in the surface 57 which opposes the back surface 111 of the compressor wheel 11 mentioned above. The non-contact seal 8 containing this is formed. The plurality of recesses 81 are arranged side by side in the circumferential direction and the radial direction of the rotation shaft 2, and are formed in a hemispherical shape in the axial direction of the rotation shaft 2 than the surface 57.

According to the said structure, the surface 57 which opposes the back surface 111 of the compressor wheel 11 and the back surface 111 of the housing 5 by the non-contact seal 8 containing the some recessed part 81. The compressed gas that flows between) forms a lubricating film when the rotating shaft 2 and the compressor wheel 11 rotate, and generates a gas film pressure that presses the compressor wheel 11 along the axial direction. The inclination of the axis line at the time of 2) rotation can be suppressed. Therefore, the compressor wheel 11 can be prevented from contacting the housing 5. By preventing contact between the compressor wheel 11 and the housing 5, damage caused by abrasion of the compressor wheel 11 and the housing 5 can be suppressed, and the supercharger 1 can be used for a long time. . In addition, this structure shown in FIG. 11 may be used independently of a supercharger, and may be used with some embodiment mentioned above.

As mentioned above, in some embodiment, the supercharger 1 mentioned above has the turbine wheel 12 formed in the other end in the axial direction of the rotating shaft 2, as shown to FIG. Furthermore, it is equipped. That is, the supercharger 1 mentioned above is a turbocharger provided with the compressor wheel 11 and the turbine wheel 12. In this case, since the pressure of gas, such as compressed air, which acts on the compressor wheel 11, is lower than the pressure of gas, such as, for example, exhaust gas, which acts on the turbine wheel 12, the rotary shaft 2 At the time of rotation of the compressor wheel 11, the compressor wheel 11 side moves larger than the turbine wheel 12 side. Even in the rotary shaft 2 of such a turbocharger, as mentioned above, the oil which flowed into the clearance 6 acts the oil film pressure with respect to the thrust member 3, and the inclination at the time of rotation of the rotary shaft 2 is changed. It can be suppressed.

In addition, in some embodiment mentioned above, although the turbocharger for ships was demonstrated about the turbocharger 1 as an example, the supercharger 1 is not limited to the turbocharger for ships, A various change is possible. For example, the turbocharger 1 may be a turbocharger for automobiles, or may be a device other than the turbocharger. In addition, the supercharger 1 may be configured to not include the turbine wheel 12 described above. As the supercharger 1 which does not include the turbine wheel 12, the electric compressor etc. which rotate the compressor wheel 11 with an electric motor not shown, for example are mentioned.

In addition, in some embodiment mentioned above, although the thrust member 3 was formed in the shape of a cylinder and a cone, it may be formed in the shape of a square tube or a cylinder. Moreover, in some embodiment mentioned above, although the inner surface 53 of the housing 5 was made to cover the whole periphery of the outer peripheral surface 31 of the thrust member 3 continuously, You may intermittently cover a part in the circumferential direction of the outer peripheral surface 31.

This invention is not limited to embodiment mentioned above, The form which added the deformation | transformation to embodiment mentioned above, and the form which combined these forms suitably are also included.

1: supercharger
11: compressor wheel
111: back side
12: turbine wheel
13: thrust bearing
14, 15: journal bearing
2: axis of rotation
21: outer circumference
3, 3A-3C: thrust member
31: outer circumference
32: inner circumference
33: first cross section
34: second cross section
35 tapered surface
36: Chamfer Surface
4: thrust bearing
41: outer circumference
42: inner circumference
43: cross section
5: housing
5A: Compressor Housing
5B: Turbine Housing
5C: Bearing Housing
51: thrust member storage unit
52: thrust bearing fitting
53: inner side
54: clearance forming portion
55 tapered surface
56: recess
57: cotton
6: clearance
61: small diameter part
62: enlarged neck
7: floating disc
71: outer circumference
72: inner circumference
8: non-contact seal
81: recess

Claims (9)

Rotation axis,
A compressor wheel formed at one end of the rotating shaft;
A thrust member fitted to the rotary shaft;
A thrust bearing disposed adjacent to the thrust member in the axial direction of the rotary shaft and supporting the rotary shaft in the thrust direction;
A housing accommodating the thrust member and the thrust bearing;
A clearance is formed between an outer peripheral surface of the thrust member in the direction orthogonal to the axial direction and the housing in at least a part of the axial direction and the circumferential direction of the rotational shaft, and the clearance is configured such that oil flows into the clearance.
The supercharger is comprised so that when the said rotating shaft and the thrust member rotate, the oil which flowed into the said clearance produces the oil film pressure which presses the thrust member along the direction orthogonal to the said axial direction. . The method of claim 1,
When the magnitude | size of the said clearance is C and the outer dimension of the thrust member is D, the clearance in at least one part satisfies the condition of clearance ratio C / D of 5/1000 <= C / D <10/1000 Supercharger. The method according to claim 1 or 2,
Said clearance is a supercharger in which at least one part of the thrust bearing side in the said axial direction is formed large compared with the side away from the thrust bearing. The method of claim 3, wherein
The inside dimension of the part which forms the said clearance of the said housing is a supercharger in which at least one part of the said thrust bearing side in the said axial direction is formed large compared with the side away from the said thrust bearing. The method according to claim 3 or 4,
The outer dimension of the said thrust member is a supercharger in which at least one part of the said thrust bearing side in the said axial direction is formed small compared with the side away from the said thrust bearing. The method of claim 3, wherein
The thrust member has a chamfer on at least a part of an end portion on the thrust bearing side in the axial direction. The method according to any one of claims 1 to 6,
The housing is configured such that an enlarged diameter portion, in which the clearance is partially enlarged in the circumferential direction of the rotation shaft, is arranged evenly. The method according to any one of claims 1 to 7,
And the housing is provided with a non-contact seal including a plurality of recesses on a surface of the compressor wheel that faces the rear surface of the compressor wheel. The method according to any one of claims 1 to 8,
The turbocharger further provided with the turbine wheel formed in the other end of the said rotating shaft.

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