COMPRESSOR WHEEL AND USE OF THE COMPRESSOR WHEEL

Abstract

The invention relates to a compressor wheel for a high-speed compressor composed of a polymer material, having a wheel front side (6), a wheel rear side (11) and a wheel hub (3), wherein the wheel front side (6) has a curvature, by virtue of which the distance between a plane extending radially through the outer circumference (15) of the wheel front side (6) and the surface of the wheel front side (6) increases from the outer circumference (15) toward the wheel hub (3), and guide vanes (7) are arranged on the wheel front side (6). The wheel hub (3) projects in an axial direction on the wheel rear side (11), and reinforcing ribs (13) extend from the wheel hub (3) toward the outer circumference (15), wherein the distance between a plane extending radially through the outer circumference (15) of the wheel rear side (11) and the trailing edge (19) of the reinforcing ribs (13) increases from the outer circumference (15) of the wheel rear side (11) toward the wheel hub (3).

The invention furthermore relates to the use of the compressor wheel.

Claims

1: A compressor wheel for a high-speed compressor comprising a polymer material, having a wheel front side, a wheel rear side and a wheel hub, wherein the wheel front side has a curvature, by virtue of which the distance between a plane extending radially through the outer circumference of the wheel front side and the surface of the wheel front side increases from the outer circumference toward the wheel hub, and guide vanes are arranged on the wheel front side, wherein the wheel hub projects in an axial direction on the wheel rear side, and reinforcing ribs extend from the wheel hub toward the outer circumference, wherein the distance between a plane extending radially through the outer circumference of the wheel rear side and the trailing edge of the reinforcing ribs increases from the outer circumference of the wheel rear side toward the wheel hub, wherein the wheel hub is surrounded on the wheel rear side by a concentric ring, and reinforcing ribs extend between the wheel hub and the concentric ring and from the concentric ring toward the outer circumference.

2: The compressor wheel as claimed in claim 1, wherein the reinforcing ribs have a curved trailing edge.

3. (canceled)

4: The compressor wheel as claimed in claim 1, wherein the number of reinforcing ribs between the wheel hub and the concentric ring is smaller than the number of reinforcing ribs which extend from the concentric ring toward the outer circumference.

5: The compressor wheel as claimed in claim 1, wherein the reinforcing ribs between the wheel hub and the concentric ring are aligned in a radial direction.

6: The compressor wheel as claimed in claim 1, wherein all the reinforcing ribs extend in a radial direction.

7: The compressor wheel as claimed in claim 1, wherein the reinforcing ribs extending toward the outer circumference are curved or s-shaped.

8: The compressor wheel as claimed in claim 1, wherein the polymer material is selected from the group consisting of polyaryletherketones, polysulfones, polyphenylenesulfone, polyetherimides, polyamides, polyethersulfones, polyphenylene sulfides, polyvinylidene fluoride, epoxy resins and polyesters.

9: The compressor wheel as claimed in claim 1, wherein the polymer material is fiber-reinforced.

10: The compressor wheel as claimed in claim 1, wherein the compressor wheel is a compressor wheel in an exhaust turbocharger, an electrically driven compressor for engines, a vacuum cleaner, a blower, a compressor, a fan or a vapor extraction hood.

Description

[0034] Embodiments of the invention are shown in the figures and are explained in greater detail in the following description. In the drawing:

[0035] FIG. 1 shows a compressor wheel according to the invention in side view,

[0036] FIG. 2 shows a section through a compressor wheel according to the invention,

[0037] FIG. 3 shows a depiction of the wheel hub and of the wheel body,

[0038] FIGS. 4 to 7 show various configurations of the reinforcing ribs on the wheel rear side.

[0039] A compressor wheel according to the invention is shown in side view in FIG. 1.

[0040] A compressor wheel 1 comprises a wheel hub 3 and a wheel body 5. Guide vanes 7 are arranged on the wheel body 5 on the wheel rear side 6. The guide vanes 7 are shaped in such a way that during operation of the compressor wheel the gas to be compressed is transported from the side with the largest diameter in the direction of an upper end 9 of the compressor wheel 1. For this purpose, the compressor wheel 1 normally turns at a speed of rotation of usually several thousand revolutions per minute. Thus, in the case of use in an electrically driven compressor in a motor vehicle engine, for example, speeds of rotation of up to 100,000 rpm can be reached, for example. Here, the configuration and shape of the guide vanes 7 corresponds to the generally customary shape for corresponding compressor wheels and is known to those skilled in the art. As can be seen from FIG. 1, the guide vanes 7 have a swept, s-shaped profile and change direction, wherein the guide vanes 7 are aligned in an axial direction in the region of the largest circumference and in a radial direction at the other end, in the region of the upper end 9.

[0041] According to the invention, reinforcing ribs 13 are arranged on the wheel rear side 11, which faces away from the guide vanes. The reinforcing ribs 13 extend from an outer circumference 15 toward the wheel hub 3. As can be seen from FIG. 1, the wheel hub 3 projects in an axial direction on the wheel rear side 11, and the reinforcing ribs 13 extend to the lower end 17 of the wheel hub 3. In the embodiment shown here, the reinforcing ribs have a curved trailing edge 19. In this case, the profile is concave with the smallest gradient in the region of the outer circumference 15 and the largest gradient in the region of the wheel hub 3.

[0042] Apart from the concave profile, shown here, of the trailing edge 19 of the reinforcing ribs 13, a linear profile is also possible, for example. The curved profile can be in the form of a circular segment, parabolic, elliptical or hyperbolic. A profile in the form of a circular segment, as shown in FIG. 1, is preferred.

[0043] A section through the compressor wheel shown in FIG. 1 is shown in FIG. 2.

[0044] It can be seen here that the wheel body 5 curves in a direction from the outer circumference 15 to the upper end 17. In order to avoid large wall thicknesses, which can lead to cavities and distortion due to shrinkage when the compressor wheel 1 is produced from a polymer material, the wheel body is in the form of a curved wall which has a substantially constant thickness. In order to obtain a sufficient stability of the wheel, the reinforcing ribs 13 are provided.

[0045] In the embodiment shown in FIG. 2, the wheel hub has a smaller inside diameter 21 in the region of the wheel rear side 11 than in the region of the wheel front side. In this case, the inside diameter of the wheel hub increases with an abrupt widening.

[0046] In addition to the reinforcing ribs 13, the compressor wheel 1 has a concentric ring 23, which surrounds the wheel hub 3. The reinforcing ribs 13 then extend initially from the outer circumference 15 to the concentric ring 23 and, from there, onward to the wheel hub 3. In this case, the number of reinforcing ribs 13 from the outer circumference 15 to the concentric ring 23 can be greater than the number of reinforcing ribs between the concentric ring 23 and the wheel hub 3.

[0047] Apart from designing the wheel hub 3 with an abrupt widening, as shown in FIG. 2, it is also possible to design the wheel hub 3 with a constant diameter. This can be seen from FIG. 3 by way of example. Here, FIG. 3 shows only the wheel hub 3 and the wheel body 5 for the sake of greater simplicity. The length by which the wheel hub projects on the wheel rear side is denoted by I.sub.RR. Here too, the wheel body 5 extends with a concave curvature from the outer circumference 15 to the upper end 9 of the wheel hub 3.

[0048] In FIGS. 4 to 7, various possible profiles of the reinforcing ribs 13 on the wheel rear side 11 are shown.

[0049] FIG. 4 shows the profile of the reinforcing ribs 13 as shown also in FIGS. 1 and 2. Here, the reinforcing ribs 13 extend linearly in a radial direction. In the variant shown here, the wheel hub 3 is surrounded by a concentric ring 23. In this case, the reinforcing ribs 13 extend from the outer circumference 15 to the concentric ring 23. Each second reinforcing rib 13 extends further from the concentric ring 23 to the wheel hub 3. Owing to the reduced number of reinforcing ribs 13 between the concentric ring 23 and the wheel hub 3, the distance between the individual reinforcing ribs 13 is greater than if all the reinforcing ribs 13 extended to the wheel hub 3. This is helpful especially in the manufacture of the compressor wheel 1.

[0050] FIG. 5 shows an arrangement of the reinforcing ribs in which reinforcing ribs 25 between the concentric ring 23 and the wheel hub 3 extend linearly in a radial direction and the reinforcing ribs extending from the outer circumference 15 to the concentric ring 23 are curved. In the embodiment shown here, the reinforcing ribs have a slight S shape.

[0051] With the shape shown in FIG. 6, the reinforcing ribs 13 extend in the form of a circular segment, and in the embodiment shown in FIG. 7, they likewise extend in an s shape.

[0052] With the shapes of the reinforcing ribs 13 shown in FIGS. 6 and 7, it is also possible additionally to provide the concentric ring 23.

[0053] As an alternative to the radial path of the ribs in FIG. 1, it is also possible to embody the reinforcing ribs with an angle relative to the radial direction. This is also possible with a curved profile, with the angle being determined here by drawing a connecting line between the opposites and the angle being defined between the connecting line and the radial direction.

[0054] In addition to the shapes shown here, the reinforcing ribs can also assume other profiles, being wavy or zigzag in shape for example, and, in this case too, a substantially radial path or a path at an angle relative to the radial direction is possible.

LIST OF REFERENCE SIGNS

[0055] 1 compressor wheel [0056] 3 radial hub [0057] 5 wheel body [0058] 6 wheel front side [0059] 7 guide vane [0060] 9 upper end [0061] 11 wheel rear side [0062] 13 reinforcing ribs [0063] 15 outer circumference [0064] 17 lower end [0065] 19 trailing edge [0066] 21 inside diameter of the wheel hub in the region of the wheel rear side [0067] 23 concentric ring [0068] 25 reinforcing ribs between concentric ring 23 and wheel hub 3 [0069] I.sub.RR length by which the wheel hub 3 projects on the wheel rear side 11