RESONATOR INSERT FOR INSERTION INTO AN INTAKE PIPE OF A TURBOCHARGER, TURBOCHARGER AND RESONATOR

Abstract

A resonator insert (14) is provided for coaxial and sectionally radially spaced insertion in an intake pipe of a turbocharger (10). The resonator insert (14) has a tube section (141) with a wall having circumferentially extending, axially adjacent through-slots (142). The wall of the tube section (141) carries at least one radially outwardly directed, axially extending lamella (144) crossing the through-slots (142). A turbocharger with an upstream resonator also is provided.

Claims

1. A resonator insert (14) for coaxial and sectionally radially spaced insertion into an intake pipe of a turbocharger (10), comprising: a tube section (141) having a wall with a plurality of through-slots (142) extending predominantly in a circumferential direction and axially adjacent to one another, the wall of the tube section (141) having at least one radially outwardly directed, axially extended lamella (144) crossing the through-slots (142).

2. The resonator insert (14) of claim 1, wherein the at least one lamella (144) has a radially outer edge having a radial dimension that varies along an axial length of the at least one lamella (144).

3. The resonator insert (14) of claim 1, wherein the at least one lamella (144) has a radially outer edge having a radial dimension that remains constant along an axial length of the at least one lamella (144).

4. The resonator insert (14) of claim 1, wherein the at least one lamella (144) comprises one or more through openings (146).

5. The resonator insert (14) of claim 4, wherein the at least one lamella (14) has a plurality of through openings (146) configured as circular holes of different diameters.

6. The resonator insert (14) of claim 4, wherein the at least one lamella (14) has exactly one through opening (146) occupying a major part of an area of the respective lamella area, so that the lamella (144) is reduced to a bow arching over the through opening.

7. The resonator insert (14) of claim 1, wherein the at least one lamella (14) extends over an entire axial length of the tube section (141).

8. The resonator insert (14) of claim 1, wherein the wall of the tube section (141) further carries a disc-shaped annular wall (145) that faces radially outwardly and is aligned perpendicular to the axial direction.

9. The resonator insert (14) of claim 8, wherein the annular wall (145) is arranged in an axially central region of the tube section (141) and the through-slots (142) are arranged on only one axial side of the annular wall (145).

10. The resonator insert (14) of claim 8, a radially outer edge of the lamella (14) is at the same radial height as a radially outer edge of the annular wall (145).

11. The resonator insert (14) of claim to 8, wherein the radially outer edge of the lamella (14) is at a lower radial height than the radially outer edge of the annular wall (145).

12. The resonator insert (14) of claim 8, wherein the lamella (144) extends in the axial direction from a free end of the tube section to the annular wall (145).

13. The resonator insert (14) of claim 1, wherein the at least one lamella (144) comprises a plurality of lamellae (144) of the same shape distributed over a circumference of the tube section (141).

14. A turbocharger (10) for generating an air flow in a piping system comprising. a rotatable compressor wheel (16), an intake pipe (12) located directly upstream of the compressor wheel (16) in a direction of air flow, with reduced pipe cross-sections at both ends, and a resonator insert (14) arranged coaxially in the intake pipe (12) and comprising a tube section (141) that terminates sealingly with the ends of reduced cross-section of the intake pipe (12) and has through-slots (142) extending predominantly in a circumferential direction and being axially adjacent to one another, the through slots (142) connecting an interior of the tube section (141) to a resonator chamber (18) formed between a wall of the tube section (141) and a wall of the intake pipe (12), wherein, the wall of the tube section (141) carries at least one radially outwardly directed, axially extended lamella (144) crossing the through-slots (142).

15. The turbocharger (10) of claim 14, the at least one lamella (144) has a radially outer edge that rests against the wall of the intake pipe (12).

16. The turbocharger (10) of 14, wherein the at least one lamella (144) has a radially outer edge with at least a portion of the radially outer edge of the lamella (144) being at a distance from the wall of the intake pipe (12).

17. The turbocharger (10) of claim 14, wherein the lamella (144) extends over an entire axial length of the intake pipe (12) between the ends of the intake pipe (12) that are of reduced cross-section.

18. The turbocharger (10) of claim 14, the tube section (141) further has a disc-shaped annular wall (145) that projects radially out and is perpendicular to the axial direction.

19. The turbocharger (10) of claim 18, wherein the annular wall (145) is arranged in an axially central region of the tube section (141) and the through-slots (142) are arranged only on the compressor wheel side of the annular wall (145).

20. A resonator comprising: an outer pipe (121) with reduced pipe cross-sections at both ends, and a resonator insert (14) arranged coaxially in the outer pipe (121) and comprising a tube section (141) that terminates sealingly with the ends of reduced cross-section of the outer pipe (121), the tube section (141) having a wall with axially adjacent through-slots (142) extending predominantly in a circumferential direction and via which an interior of the tube section (141) is connected to a resonator chamber (18) formed between the tube section (141) and the wall of the outer pipe (121), and at least one axially extended lamella (14) crossing the through-slots (142), the at least one lamella (14) extending at least partly between the inner tube section (141) and the outer pipe (121) and connected to at least one of the inner tube section (141) and the outer pipe (121).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 is partial sectional view of a known turbocharger with resonator insert dummy.

[0026] FIG. 2 is a perspective view of a resonator insert according to the invention.

[0027] FIG. 3 is a cross-sectional view of the intake pipe of the turbocharger of FIG. 1 with resonator insert of FIG. 2.

[0028] FIG. 4 is a perspective view of a resonator insert according to a second embodiment of the invention.

[0029] FIG. 5 is a perspective view of a resonator insert according to a third embodiment of the invention.

[0030] FIG. 6 is a perspective view of a resonator insert according to a fourth embodiment of the invention.

[0031] FIG. 7 is a perspective view of a resonator insert according to a fifth embodiment of the invention.

[0032] FIG. 8 is a perspective view of a resonator insert according to a sixth embodiment of the invention.

[0033] FIG. 9 is a perspective view of a resonator insert according to a seventh embodiment of the invention.

DETAILED DESCRIPTION

[0034] Like reference signs in the figures indicate like or analogous elements.

[0035] FIG. 1 is a partially cutaway view of a known turbocharger 10 with an intake pipe 12 and a dummy of a resonator insert 14 inserted therein. FIG. 1 serves merely to illustrate the typical positioning of the resonator insert 14 in a turbocharger with respect to both known resonator inserts 14 and those according to the invention. The resonator insert 14 in FIG. 1 merely is a tube section 141 positioned immediately upstream of the compressor wheel 16 of the turbocharger 10 in the direction of flow. The intake pipe 12 forms an outer pipe 121 in which the resonator insert 14 is fixed coaxially In the axial central region of the resonator insert 14, the inner diameter of the outer pipe 121 is larger than the outer diameter of the tube section 141. In the end regions of the resonator insert 14, however, the outer pipe 121 tapers in such a way that it clamps the tube section 141 in a sealing manner. This creates an annular resonator chamber 18 that is in air-exchanging communication with the interior of the resonator insert 14 via acoustic slots not shown in FIG. 1 (142 cf. FIGS. 2 and 3). Such an arrangement acts in a known manner as a Helmholtz resonator.

[0036] FIG. 2 shows a first embodiment of a resonator insert 14 according to the invention. The resonator insert 14 could be inserted in the intake pipe 12 of the turbocharger 10 of FIG. 1. Clearly visible are the narrow acoustic slots 142 extending in the circumferential direction and arranged side by side in the axial direction in a gill-like manner. These cannot, of course, run completely around the circumference of the tube section 141. However, to come as close as possible to this technically unfeasible ideal situation, the acoustic slots 142 are divided into only four angular sections of equal size, each separated from the others in the circumferential direction by narrow webs 143.

[0037] The present invention is aimed at preventing annular flow in the resonator chamber 18. To this end, in the embodiment shown, two opposed lamellae 144 extend radially out from the tube section 141, as shown in FIG. 3, so that they abut the intake pipe 12 or outer pipe 121. The resonator chamber 18 is thus divided into two half-ring chambers, each of which acts as a Helmholtz resonator (with halved volume) in a known manner, but which no longer have any direct connection with each other, so that an annular flow circulating the tube section 141 is not possible.

[0038] In the embodiment shown, the tube section 141 is surrounded by an annular wall 145 that is perpendicular to the axial direction and has the same radial height as the lamellae 144. Thus, the annular wall 145 rests with its radially outer edge against the intake pipe 12 or outer pipe 121 and divides the annular chamber 18 into two axial sections separated from each other. In the embodiment shown, however, only the axial section on the left in FIGS. 2 and 3 is connected to the interior of the tube section 141 via acoustic slots 142 and is therefore effective as a Helmholtz resonator. The axial section on the right in FIGS. 2 and 3 is ineffective from an acoustic point of view. By a different choice of the axial position of the annular wall 145, modified acoustic properties can be obtained. It is also conceivable to provide both axial sections with acoustic slots 142 and to create two effective Helmholtz resonators whose annular chambers can also interact with each other if the annular wall 145 is radially lower or perforated. Of course, it is also possible to use multiple annular walls 145 or to dispense with the use of an annular wall 145 entirely. The skilled person will recognize that by all these measures the acoustic properties of the resulting resonator can be very finely tuned to the particular requirements of the individual case.

[0039] FIGS. 4 to 9 show alternate embodiments of the resonator insert according to the invention to the embodiment of FIG. 2, for which mutatis mutandis the same variation possibilities apply as described above in the context of the embodiment of FIG. 2. What the embodiments of FIGS. 4 to 9 have in common is that, in contrast to the embodiment of FIGS. 2 and 3, they do not effect a complete separation of the half-ring chambers created by the lamellae 144, so that all regions of the resonator chamber 18 are in direct air-exchanging communication with one another. From an acoustic point of view, this corresponds to an enlargement of the effective resonator chamber compared to the embodiment of FIGS. 2 and 3, which has a particularly positive effect on the attenuation of low sound frequencies. With regard to the suppression by the resonator chamber 18 of the annular flow recognized as harmful, they are admittedly less effective—in particular, only an obstruction and not a complete suppression of said annular flow takes place. However, this remaining obstruction is sufficient to achieve the desired effect of the broadening of the characteristic diagram to a sufficient extent.

[0040] In the embodiment of FIG. 4, the lamellae 144 in the area close to the compressor wheel do not fit exactly against the obliquely tapering intake pipe 12 or the outer pipe 121. In this area, therefore, an annular connection remains between the partial chambers.

[0041] The situation is reversed in the embodiment shown in FIG. 5, where the lamellae 144 are in contact with the intake pipe 12 or the outer pipe 121 only in the area of their end close to the compressor wheel. Here, in particular near the annular wall, there is an annular connection between the partial chambers.

[0042] In the embodiments of FIGS. 6 and 7, the radial height of the lamellae 144—to varying degrees—is chosen to be lower over their entire axial length than would be required for a sealing division into two half chambers.

[0043] Finally, FIGS. 8 and 9 are characterized by through-holes 146 in the lamellae. In the embodiment of FIG. 8, several through-holes 146 are provided, and are designed as circular holes with different diameters. By selecting the number and diameter of these circular holes, the acoustic properties of the resulting resonator can be tuned finely. In the embodiment of FIG. 9, on the other hand, only one through hole 146 is provided and is adapted to the outer contour of the lamella to occupy the major part of the lamella surface. The lamella 144 is thus reduced to a bow that rests against the intake pipe 12 or outer pipe 121 and spans the passage opening 146 in an arc-like manner.

[0044] Of course, the embodiments discussed in the specific description and shown in the figures are only illustrative examples of embodiments of the present invention. The person skilled in the art is provided with a wide range of possible variations in light of the present disclosure. In particular, the specific dimensioning of the individual components of the resonator insert according to the invention must be adapted to the acoustic and characteristic field requirements of the individual case. With regard to the choice of materials used, in particular metal and/or plastic, the person skilled in the art will also know how to orient himself to the requirements of the individual case.

LIST OF REFERENCE SIGNS

[0045] 10 Turbocharger [0046] 12 Intake pipe [0047] 121 Outer pipe [0048] 14 Resonator insert [0049] 141 Pipe section [0050] 142 Through-slot/Acoustic slot [0051] 143 Web [0052] 144 Lamella [0053] 145 Ring wall [0054] 146 Passage opening