JP2009167882A - Centrifugal impeller - Google Patents

Abstract

The present invention provides a centrifugal impeller capable of reducing weight and improving rigidity.
In a centrifugal impeller 1, a plurality of blades 4, a disk main body 3 rotatable around a rotation axis L1, and a back surface of the disk main body 3 are formed, and an outer peripheral side is inclined rearward from the rotation shaft side. The punching structure 5 having the inclined surface 5 a and the annular reinforcing member 7 that reinforces the rigidity of the disc body 3 are provided. With such a configuration, the centrifugal impeller can be reduced in weight and the rigidity against centrifugal force can be improved without changing the front shape of the disk main body 3 that affects the fluid flow.
[Selection] Figure 1

Description

  The present invention relates to a centrifugal impeller.

Conventionally, as a technology in such a field, there is JP-A-2003-269383. In the structure of the impeller of the compressor described in this publication, the vibration of the blade due to centrifugal stress is provided by providing a connecting member that connects adjacent blades to each other at least on the outer peripheral side of the plurality of blades of the impeller. Is suppressed, stress concentration at the base of the blade is prevented, and durability is improved. In general, in this type of impeller, measures against centrifugal stress are taken by adopting a wide structure in which the disk becomes thicker as it approaches the rotation axis.
JP 2003-269383 A

  However, in the prior art described in the above-mentioned patent document, since the rotating shaft side of the disk has a wide structure, there is a problem that the outer peripheral side of the disk may be deformed and contact the shroud due to thermal expansion during operation. . Moreover, in the prior art, since the rotating shaft side of the disk has a wide structure, there is a problem that the mass is increased and the dynamic performance of the centrifugal impeller is prevented from being improved.

  Therefore, a structure that improves the dynamic performance of the centrifugal impeller by reducing the weight of the disc and reducing the disc weight by providing a dent on the back of the disc and making the disc rotating shaft side thinner. Conceivable. However, in such a structure, if the centrifugal force is excessive, the disc may be deformed by the centrifugal force.

  The present invention has been made to solve the above problems, and an object thereof is to provide a centrifugal impeller capable of reducing weight and improving rigidity.

  The centrifugal impeller according to the present invention is a centrifugal impeller having a disk body that is provided with a plurality of blades on a front surface that is one main surface and is rotatable around a rotation axis, and is formed on the back surface of the disk body, It is characterized by comprising an bore structure having an inclined surface whose outer peripheral side is inclined rearward relative to the rotating shaft side, and an annular reinforcing member for reinforcing the rigidity of the disc body.

  In the centrifugal impeller according to the present invention, a counterbored structure is formed on the back surface of the disk main body, and an annular reinforcing member for reinforcing the rigidity of the disk main body is provided. With such a configuration, it is possible to reduce the weight of the centrifugal impeller without affecting the shape of the front surface of the disk body forming the flow path. Furthermore, the rigidity of the centrifugal impeller can be improved by providing an annular reinforcing member so as to reinforce the rigidity of the disc body.

  In the centrifugal impeller according to the present invention, the annular reinforcing member is preferably embedded in the disc body. Thereby, the rigidity of the disc body can be improved.

  Alternatively, in the centrifugal impeller according to the present invention, an annular first protrusion is formed on the back surface of the disk body so as to protrude rearward and centering on the rotation axis, and the annular reinforcing member is formed of the annular first protrusion. It is preferable that it is mounted on the outer peripheral surface. With such a configuration, the annular reinforcing member regulates the deformation of the disc body due to the centrifugal force via the first protrusion. Therefore, the centrifugal impeller can improve the rigidity against the deformation of the disc body.

  Further, in the centrifugal impeller according to the present invention, the first protrusion is formed on the outer peripheral side of the back surface of the disc body, and protrudes rearward from the inclined surface of the counterbored structure and has an annular first centered on the rotation axis. Preferably, two protrusions are formed, and annular reinforcing members are respectively attached to the outer peripheral surfaces of the first protrusion and the second protrusion. With such a configuration, the annular reinforcing member regulates the deformation of the disc main body in the radial direction via the first protrusion, and restricts the deformation of the disk main body falling forward via the second protrusion. To do. Therefore, it is possible to further improve the rigidity against the deformation of the disc body.

  According to the centrifugal impeller of the present invention, it is possible to reduce the weight and improve the rigidity.

  Hereinafter, a first embodiment of a centrifugal impeller according to the present invention will be described with reference to the drawings. In the figure, the same reference numerals are used for the same or corresponding parts.

  FIG. 1 is a perspective view showing the centrifugal impeller according to the first embodiment, and FIG. 2 is an end view along the rotation axis of the centrifugal impeller according to the first embodiment. In the end view of the present specification, only one of the centrifugal impellers that are rotationally symmetric is illustrated and described.

  As shown in FIGS. 1 and 2, the centrifugal impeller 1 is formed around a cylindrical boss portion 2 extending along the rotation axis L1. The boss portion 2 is provided with a disk body 3 that extends in the circumferential direction. A plurality of blades 4 curved in the circumferential direction of the boss portion 2 are formed on the front surface of the disk body 3.

  Further, on the back surface of the disc body 3, a hollow structure 5 is formed around the boss portion 2. This bore structure 5 has an inclined surface 5a whose outer peripheral side is inclined rearward relative to the rotation axis L1 side. In general, stainless steel, aluminum, titanium, or the like is used as the material of the disc body 3.

  The inclined surface 5a surrounds the boss portion 2 and is formed over the entire circumference. For example, the inclined surface 5a is formed in the radial direction from the boss portion 2 to substantially the center. Thus, by forming the hollow structure 5 recessed forward, the thickness of the disk main body 3 is made thinner and uniform than in the prior art.

  An annular protrusion (first protrusion) 6 protruding rearward is formed around the boss 2 at the outer edge of the bore structure 5, and the disc body 3 is formed on the outer peripheral surface of the protrusion 6. An annular reinforcing member 7 for reinforcing the rigidity is attached. As the reinforcing member 7, a material having higher rigidity and lighter weight than that of the disc body 3 is used, and for example, carbon fiber is preferable.

  Next, for comparison, a conventional centrifugal impeller will be described with reference to the drawings.

  FIG. 3 is an end view showing a conventional centrifugal impeller. As shown in FIG. 3, when the centrifugal impeller 51 rotates, a centrifugal force F is generated in the radial direction. The centrifugal force F increases in accordance with the rotational speed of the centrifugal impeller 51, and the stress is concentrated on the connection portion between the boss portion 52 and the disc main body 53. As shown in FIG. 3, the conventional centrifugal impeller 51 has a tapered structure in which the back surface of the disk main body 53 is inclined rearward as it is closer to the boss portion 52. Thus, in the conventional centrifugal impeller 51, the rigidity with respect to the centrifugal force F is increased by increasing the thickness of the connecting portion between the boss portion 52 and the disk main body 53.

  FIG. 4 is a schematic view showing a use state of a conventional centrifugal impeller in a high temperature environment. When the centrifugal impeller 51 is used in a high temperature environment, thermal stress accompanying thermal expansion is generated inside the centrifugal impeller 51. At this time, fluid such as air is flowing on the front side of the disc main body 53, so that the back side is often hotter than the front side of the disc main body 53. As shown in FIG. 4, in the centrifugal impeller 51 in a high temperature environment, heat is transferred from the high temperature gas G to the back surface of the disk body 53 on the back surface side of the disk body 53. As a result, deformation T due to thermal expansion occurs in the direction along the back surface of the disk main body 53.

  FIG. 5 is a schematic view showing a deformation state of a conventional centrifugal impeller. When the centrifugal impeller 51 is used in a high temperature environment, the centrifugal force F shown in FIG. 3 and the deformation T due to thermal expansion shown in FIG. 4 occur simultaneously. As a result, as shown in FIG. 5, in the conventional centrifugal impeller 51, there is a consideration that the peripheral end portion of the disc body 3 falls forward due to the cooperation of the centrifugal force F and the deformation T due to thermal expansion.

  In contrast to such a conventional centrifugal impeller 51, as shown in FIGS. 1 and 2, the centrifugal impeller 1 according to the first embodiment forms a counterbored structure 5 on the back surface of the disc body 3. Thereby, the centrifugal impeller 1 can reduce the weight of the centrifugal impeller 1 without changing the shape of the front side of the disc body 3 that affects the flow of fluid.

  Furthermore, in the centrifugal impeller 1 according to the first embodiment, the counterbored structure 5 has an inclined surface 5a whose outer peripheral side is inclined rearward relative to the rotation axis L1 side. Here, FIG. 6 is a schematic view showing a use state of the centrifugal impeller according to the first embodiment in a high temperature environment.

  As shown in FIG. 6, in the centrifugal impeller 1, an inclined surface 5 a is formed on the back side of the disc body 3. For this reason, the deformation T due to thermal expansion occurs along the inclined surface 5a inclined backward. The deformation T due to the thermal expansion acts in a direction in which the disc main body 3 is tilted backward, and the centrifugal force F acting in a direction in which the disc main body 3 is tilted forward is relaxed. In this manner, the centrifugal impeller 1 can be made difficult to fall forward in a high temperature situation.

  Moreover, the centrifugal impeller 1 according to the first embodiment is provided with an annular reinforcing member 7 on the outer peripheral surface of the protrusion 6. Here, FIG. 7 is a front view showing the annular reinforcing member according to the first embodiment. As shown in FIG. 7, the annular reinforcing member 7 made of carbon fiber or the like has high rigidity in the circumferential direction. For this reason, the reinforcing member 7 attached to the annular protrusion 6 restricts the radial deformation of the disc body 3 due to the centrifugal force F via the protrusion 6. Thereby, the reinforcing member 7 can increase the rigidity with respect to the centrifugal force F of the disc body 3. Further, in the centrifugal impeller 1, since the reinforcing member 7 is firmly fixed to the protrusion 6 by the centrifugal force during operation, no fixing parts such as bolts or adhesives are required, and the disk main body 3 is configured with a simple configuration. Deformation can be prevented.

  Further, in the turbocharger equipped with such a centrifugal impeller 1, since the weight of the centrifugal impeller 1 is reduced, the weight of the vehicle equipped with the turbocharger can be reduced, the acceleration performance can be improved, and the fuel efficiency can be improved. Improvements are being made. Moreover, in the turbocharger provided with the centrifugal impeller 1, it is possible to improve the starting characteristics and the response performance.

  In addition, in the turbocharger provided with the centrifugal impeller 1, since the rigidity of the disc body 3 is improved, the forward deformation of the disc body 3 is suppressed, and the shroud and the blade 4 covering the centrifugal impeller 1 are suppressed. Can be reduced.

  Next, 2nd Embodiment of the centrifugal impeller which concerns on this invention is described with reference to drawings. FIG. 8 is an end view along the rotation axis of the centrifugal impeller according to the second embodiment.

  The centrifugal impeller 11 according to the second embodiment shown in FIG. 8 is different from the centrifugal impeller 1 according to the first embodiment in that instead of the disc main body 3 in which the annular protrusion 6 is formed as a protrusion, Instead of the point provided with the disc main body 13 in which the annular first protrusion 16 and the annular second protrusion 17 are formed, and the reinforcing member 7 mounted on the outer peripheral surface of the annular protrusion 6, an annular shape is provided. It is the point provided with the linear 1st reinforcement member 18 and the 2nd reinforcement member 19 with which the outer peripheral surface of the 1st protrusion part 16 and the 2nd protrusion part 17 was each mounted | worn. Since other components are the same as those in the first embodiment, description thereof is omitted. Hereinafter, also in other embodiments, description of the same components as those in the first embodiment will be omitted.

  As shown in FIG. 8, in the centrifugal impeller 11 according to the second embodiment, a counterbored structure 15 is formed on the back surface of the disc body 13. An annular first protrusion 16 protruding rearward is formed around the boss 2 at the outer edge of the bore structure 15, and a linear first protrusion 16 is formed on the outer peripheral surface of the annular first protrusion 16. One reinforcing member 18 is wound with a predetermined tension.

  In addition, the bore structure 15 has an inclined surface 15a that inclines backward as it is spaced outward from the rotation axis L1 side. An annular second protrusion 17 protruding rearward is formed on the inclined surface 15a with the rotation axis L1 as the center, and a linear second reinforcement is formed on the outer peripheral surface of the annular second protrusion 17. The member 19 is wound with a predetermined tension. As these 1st reinforcement member 18 and the 2nd reinforcement member 19, rigidity higher than the disc main body 13 and a lightweight linear member (light weight highly rigid fiber member) are used, For example, a carbon fiber is preferable. Moreover, the 1st reinforcement member 18 and the 2nd reinforcement member 19 are wound by the cyclic | annular 1st protrusion 16 and the 2nd protrusion 17, and comprise the cyclic | annular reinforcement member.

  According to the centrifugal impeller 11 having such a configuration, the first reinforcing member 18 restricts deformation of the disk main body 13 in the radial direction, and the second reinforcing member 19 prevents the disk main body 13 from being collapsed forward. Can be regulated. For this reason, in the centrifugal impeller 11 according to the second embodiment, it is possible to more effectively improve the rigidity against the deformation of the disc body 13.

  Further, in the centrifugal impeller 11, the first reinforcing member 18 and the second reinforcing member 19 are firmly fixed to the first protrusion 16 and the second protrusion 17 by the centrifugal force during operation. In addition, the disk main body 13 can be prevented from being deformed with a simple configuration.

  Then, 3rd Embodiment of the centrifugal impeller which concerns on this invention is described with reference to drawings. FIG. 9 is an end view along the rotation axis of the centrifugal impeller according to the third embodiment.

  The centrifugal impeller 21 according to the third embodiment shown in FIG. 9 is different from the centrifugal impeller 1 according to the first embodiment in that an annular recess is used instead of the disc body 3 on which the annular protrusion 6 is formed. An annular reinforcing member 25 attached to an annular recess 24 is attached in place of the reinforcing member 7 attached to the outer peripheral surface of the annular protrusion 6 and a point having a disk main body 23 formed with 24. It is a point.

  In the centrifugal impeller 21, an annular recess 24 centered on the rotation axis L1 is formed on the back surface of the disk body 23. The annular recess 24 is formed on the outer edge of the disc main body 23 and is recessed from the back to the front. The recess 24 may be formed at a place other than the outer edge as long as it is the back surface of the disk main body 23. The reinforcing member 25 is firmly fixed to the inner peripheral wall surface 24 a of the annular recess 24 by the centrifugal force during operation. The centrifugal impeller 21 configured in this manner also exhibits the same operations and effects as the centrifugal impeller 1 of the first embodiment.

  Next, 4th Embodiment of the centrifugal impeller which concerns on this invention is described with reference to drawings. FIG. 10 is an end view along the rotation axis of the centrifugal impeller according to the fourth embodiment.

  The centrifugal impeller 31 according to the fourth embodiment shown in FIG. 10 is different from the centrifugal impeller 1 according to the first embodiment in that an annular protrusion is used instead of the disc body 3 on which the annular protrusion 6 is formed. A point provided with a disk main body 33 in which no part is formed, and a point provided with a plurality of reinforcing members 34 to 36 embedded in the disk main body 33 instead of the reinforcing member 7 mounted on the outer peripheral surface of the annular protrusion 6. It is. Reinforcing members 37 to 39 are embedded in the boss portion 32 of the centrifugal impeller 31, and these reinforcing members 34 to 39 have an annular shape centering on the rotation axis L1. In the centrifugal impeller 31 configured as described above, the rigidity of the boss portion 32 and the disk main body 33 can be increased by the annular reinforcing members 34 to 39.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the said embodiment. For example, a recess may be formed on the back surface of the disc body in addition to the protrusions. The number of protrusions and recesses is not limited to the above embodiment, and two or more may be formed.

  Further, it may be combined with mounting a reinforcing member by forming protrusions and recesses and embedding the reinforcing member inside the centrifugal impeller, and as the reinforcing member, an integrally formed annular reinforcing member and A wire-like reinforcing member or the like may be arbitrarily combined.

  Further, in the above embodiment, the reinforcing member is made of carbon fiber, but other materials may be used. In short, any material that has higher rigidity than the disk body and can reinforce the rigidity of the disk body. Good.

  Moreover, although the said embodiment demonstrated the turbocharger provided with the centrifugal impeller, you may apply the centrifugal impeller of this invention to a gas turbine engine, for example.

It is a perspective view which shows the centrifugal impeller which concerns on 1st Embodiment. It is an end view which follows the rotating shaft of the centrifugal impeller which concerns on 1st Embodiment. It is an end view along the rotating shaft of the conventional centrifugal impeller. It is the schematic which shows the use condition in the high temperature environment of the conventional centrifugal impeller. It is the schematic which shows the deformation | transformation state of the conventional centrifugal impeller. It is the schematic which shows the use condition in the high temperature environment of the centrifugal impeller which concerns on 1st Embodiment. It is a front view which shows the cyclic | annular reinforcement member which concerns on 1st Embodiment. It is an end view which follows the rotating shaft of the centrifugal impeller which concerns on 2nd Embodiment. It is an end view which follows the rotating shaft of the centrifugal impeller which concerns on 3rd Embodiment. It is an end view which follows the rotating shaft of the centrifugal impeller which concerns on 4th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 11, 21, 31 ... Centrifugal impeller 2, 32 ... Boss part 3, 13, 23, 33 ... Disc main body, 4 ... Blade | wing 5, 15 ... Outward structure, 5a, 15a ... Inclined surface, 6, DESCRIPTION OF SYMBOLS 16 ... Projection (1st projection), 17 ... 2nd projection, 7, 18, 19, 25, 34, 35, 36, 37, 38, 39 ... Reinforcement member, 24 ... Recess, 24a ... Wall surface.

Claims (4)

A centrifugal impeller provided with a plurality of blades on the front which is one main surface and having a disc body rotatable around a rotation axis,
A bore structure having an inclined surface formed on the back surface of the disc body and having an outer peripheral side inclined backward rather than the rotating shaft side;
A centrifugal impeller comprising an annular reinforcing member for reinforcing the rigidity of the disk main body.   The centrifugal impeller according to claim 1, wherein the annular reinforcing member is embedded in the disk body. On the back surface of the disk main body, an annular first protrusion centering on the rotation shaft is formed to protrude rearward,
The centrifugal impeller according to claim 1 or 2, wherein the annular reinforcing member is mounted on an outer peripheral surface of the annular first protrusion. The first protrusion is formed on the outer peripheral side of the back surface of the disc body,
The inclined surface of the bore structure is formed with an annular second protrusion that protrudes rearward and centered on the rotation axis,
The centrifugal impeller according to claim 3, wherein the annular reinforcing members are respectively attached to outer peripheral surfaces of the first protrusion and the second protrusion.

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