Air Duct of an Internal Combustion Engine

Abstract

An air duct of an internal combustion engine has an inner pipe providing a flow channel and a housing with a first housing part and a second housing part, wherein the inner pipe is arranged in the housing. The first housing part and the second housing part enclose a chamber between the inner pipe and the housing. The inner pipe has at least one section with perforations in a wall of the inner pipe, wherein the perforations completely penetrate the wall of the inner pipe. A cylindrical acoustic component at least partially encloses the at least one section of the inner pipe at an outer side of the inner pipe. A wall of the cylindrical acoustic component is provided, at least in sections thereof, with continuous openings. The flow channel is acoustically connected via the perforations and via the continuous openings to the chamber.

Claims

1. An air duct of an internal combustion engine, the air duct comprising: an inner pipe comprising a flow channel; a housing comprising a first housing part and a second housing part, wherein the inner pipe is arranged in the housing, and wherein the first housing part and the second housing part enclose at least one chamber disposed between the inner pipe and the housing; wherein the inner pipe comprises at least one section comprising perforations in a wall of the inner pipe, wherein the perforations completely penetrate the wall of the inner pipe; at least one cylindrical acoustic component at least partially enclosing the at least one section of the inner pipe at an outer side of the inner pipe; wherein a wall of the at least one cylindrical acoustic component comprises, at least in sections thereof, continuous openings; wherein the flow channel is acoustically connected via the perforations and via the continuous openings to the at least one chamber.

2. The air duct according to claim 1, wherein the at least one cylindrical acoustic component comprises a slot extending along a longitudinal axis of the inner pipe.

3. The air duct according to claim 2, wherein the at least one acoustic component is comprised of a multi-part configuration.

4. The air duct according to claim 1, wherein the at least one cylindrical acoustic component is comprised of a multi-part configuration.

5. The air duct according to claim 1, wherein the at least one cylindrical acoustic component is a sleeve arranged about the at least one section.

6. The air duct according to claim 1, wherein the at least one chamber is a broadband silencer chamber or a resonator chamber.

7. The air duct according to claim 1, wherein the at least one cylindrical acoustic component is a broadband silencer or a resonator.

8. The air duct according to claim 1, wherein the at least one section, at least in sections thereof, is a lattice with stays extending longitudinally and transversely.

9. The air duct according to claim 1, wherein the inner pipe comprises two or more of the at least one section arranged sequentially and wherein the two or more of the at least one section each comprise one of the at least one cylindrical acoustic component.

10. The air duct according to claim 1, wherein the inner pipe comprises first openings upstream and/or downstream of the at least one section along a longitudinal axis of the inner pipe, wherein the first openings of the inner pipe are acoustically connected to a volume arranged between the inner pipe and an inner wall of the housing.

11. The air duct according to claim 10, wherein the inner pipe comprises at least one second opening with an acoustic connection to the volume arranged between the inner pipe and the inner wall of the housing and/or to the at least one chamber disposed between the inner pipe and the housing.

12. The air duct according to claim 1, further comprising an adsorber element comprising at least one absorber medium, wherein the adsorber element is arranged between the outer side of the inner pipe and the at least one cylindrical acoustic component.

13. The air duct according to claim 12, wherein the at least one adsorber medium is a nonwoven.

14. The air duct according to claim 13, wherein the adsorber element is cylindrical and surrounds at least the at least one section of the inner pipe at the outer side of the inner pipe.

15. The air duct according to claim 12, wherein the adsorber element is a sleeve and comprises a slot extending along a longitudinal axis of the inner pipe, wherein the sleeve is placed or pushed about the inner pipe.

16. The air duct according to claim 12, wherein the at least one adsorber medium comprises at least one active carbon-containing layer, wherein the active carbon-containing layer comprises a gas-permeable carrier layer and an active carbon layer arranged on the gas-permeable carrier layer.

17. The air duct according to claim 16, wherein the at least one active carbon-containing layer further comprises a gas-permeable holding layer covering the active carbon layer.

18. The air duct according to claim 1, wherein the air duct is configured to be arranged at a clean air side of an air inlet of the internal combustion engine or at a raw air side of an air inlet of the internal combustion engine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Further advantages result from the following drawing description. In the drawings, embodiments of the invention are illustrated. The drawings, the description, and the claims contain numerous features in combination. A person of skill in the art will consider the features expediently also individually and combine them to expedient further combinations.

[0037] FIG. 1 shows an inner pipe of an air duct according to an embodiment of the invention in an isometric illustration.

[0038] FIG. 2 shows an acoustic component for an air duct according to an embodiment of the invention in isometric illustration.

[0039] FIG. 3 shows an adsorber element for an air duct according to an embodiment of the invention in isometric illustration.

[0040] FIG. 4 shows the inner pipe of FIG. 1 with the mounted acoustic component of FIG. 2.

[0041] FIG. 5 shows a longitudinal section of an air duct according to a further embodiment of the invention.

[0042] FIG. 6 shows an exploded illustration of the air duct according to FIG. 5.

[0043] FIG. 7 shows an exploded illustration of an inner pipe of an air duct in a further embodiment.

[0044] FIG. 8 shows the inner pipe of FIG. 7 with the mounted acoustic component.

[0045] FIG. 9 schematically shows the adsorber medium with is various layers.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0046] In the Figures, same or similar components are identified with same reference characters.

[0047] FIG. 1 shows an inner pipe 10 of an air duct 100 according to an embodiment of the invention in isometric illustration, while FIG. 2 shows an acoustic component 30 for an air duct 100 according to an embodiment of the invention in isometric illustration and FIG. 3 shows an optional adsorber element 40 for an air duct 100 according to an embodiment of the invention in isometric illustration. In FIG. 4, the inner pipe 10 of FIG. 1 is illustrated with the mounted acoustic component of FIG. 2 while FIG. 5 shows a longitudinal section of an air duct 100 with three sequentially arranged chambers 48, 28 according to a further embodiment of the invention. FIG. 6 shows in this context an exploded illustration of an air duct according to the further embodiment of the invention. FIGS. 7 and 8 show further embodiments in which acoustic components 30 and adsorber elements 40 comprise a particularly wide slot at the circumference.

[0048] As can be seen in particular in FIG. 5, the air duct 100 of an internal combustion engine, in particular of a motor vehicle, comprises an inner pipe 10 as a flow channel 12 for the fluid, in particular air. In this context, the inner pipe 10 is arranged in a housing 20 with a first housing part 22 and a second housing part 24. The housing parts 22, 24 enclose in the mounted state at least one chamber 28 between inner pipe 10 and housing 20. The chamber 28 can be a resonator chamber or a broadband silencer chamber.

[0049] In FIG. 1, it can be seen that at least one section 14 of the inner pipe 10 comprises perforations 16 in a wall 11 of the inner pipe 10 which completely penetrate the wall 11. For this purpose, the wall 11 of the inner pipe 10 is embodied in the at least one section 14, at least in sections thereof, as a lattice 17 with stays 19 extending longitudinally and transversely.

[0050] At least one cylindrical acoustic component 30 is provided that surrounds the at least one section 14 of the inner pipe 10 at an outer side 13 of the inner pipe 10 at least partially, as can be seen in FIG. 4.

[0051] A wall 31 of the at least one acoustic component 30 which is illustrated in FIG. 2 comprises, at least in sections thereof, continuous openings 32 via which the flow channel 12 via the perforations 16 is acoustically connected with the at least one chamber 28. In this way, the silencing properties of the acoustic component 30 can become effective in interaction with the chamber 28. For this purpose, the at least one acoustic component 30 can be designed advantageously as a broadband silencer.

[0052] As illustrated in an exemplary fashion in FIG. 4, the at least one acoustic component 30 is arranged as a sleeve about the at least one section 14 of the inner pipe 10. For mounting the acoustic component 30 on the inner pipe 10, the acoustic component 30 can comprise a slot 34 along the longitudinal axis L. In this way, the acoustic component 30 can be, for example, bent open in order to be thus pushed onto the inner pipe 10. After mounting, the slot 34 closes again due to the inherent elasticity of the acoustic component which is manufactured of plastic material, for example, as an injection molded part. In this way, the acoustic component 30 is subsequently seated fixedly enclosing the inner pipe 10.

[0053] The inner pipe 10 comprises openings 18 upstream and/or downstream of the section 14 along the longitudinal axis L which are acoustically connected with a volume 36 that is arranged between the inner pipe 10 and the inner wall 26 of the housing 20.

[0054] Between the outer side 13 of the inner pipe 10 and the acoustic component 30, optionally an adsorber element 40 with at least one adsorber medium 42, in particular embodied as nonwoven, can be arranged. The adsorber medium 42 can be provided in particular for adsorption of hydrocarbons (HO).

[0055] Such an adsorber element 40 is illustrated in FIG. 3. The adsorber element 40 is embodied cylindrical and surrounds at least the at least one section 14 of the inner pipe 10 at the outer side 13 of the inner pipe 10.

[0056] The adsorber element 40, like the acoustic component 30, can be slotted along the longitudinal axis L and can be placed or pushed as a sleeve about the inner pipe 10, in particular as an overlapping sleeve.

[0057] The adsorber medium 42 can comprise at least one active carbon-containing layer, comprising a gas-permeable carrier layer on which an active carbon layer is arranged. In particular, the active carbon layer can be covered by a gas-permeable holding layer.

[0058] Since the adsorber element 40 in the mounted state is arranged between inner pipe 10 and the acoustic component 30, it cannot be directly seen in FIGS. 4 and 5 so that the lead lines of the reference characters are therefore illustrated in dashed lines.

[0059] In a further embodiment which is illustrated in FIGS. 5 and 6, the inner pipe 10 can also comprise two sections 14, 15 following each other and each comprising an acoustic component 30, as can be seen in longitudinal section in FIG. 5 as well as in the exploded illustration in FIG. 6. In this context, both sections 14, 15 are provided with an acoustic component 30, respectively, wherein the openings 32 of the acoustic component 30 can be embodied differently, respectively, in order to realize different acoustic silencing properties.

[0060] The resonator chambers 28 or broadband silencing chambers 28 in the sections 14 and 15, as well as the volume 36, are separated from each other by separating walls 46 which are connected to the inner pipe 10 so that the corresponding air volumes are decoupled. In front of the chambers 28, a further resonator chamber 48 with a volume is arranged.

[0061] Furthermore, the inner pipe 10 comprises a bypass opening 44 with an acoustic connection to the resonator chamber 48 in front of the volume 36, in FIG. 5 to the left of volume 36, as can be seen in longitudinal section in FIG. 5. Venting can be realized via openings 21 (FIGS. 1, 4). In this way, a suitable venting of an adsorber element as well as also of the acoustic component can be realized.

[0062] In a non-illustrated embodiment, such a venting action can also be dispensed with. In this context, the acoustic component 30 can be provided in combination with the adsorber element 40 or even without adsorber element 40.

[0063] FIG. 7 shows in an exploded illustration a further embodiment of an inner pipe 10 of an air duct 100 and a further embodiment of an optional adsorber element 40. A cylindrical acoustic component 30 comprises a wide slot 34 so that the acoustic component is not closed about the circumference, in particular comprises an open region of 10° to 45°, in particular of 20° to 30°, in relation to the circumference.

[0064] Between the outer side 13 of the inner pipe 10 and the acoustic component 30, an adsorber element 40 with at least one adsorber medium 42, in particular embodied as a nonwoven, can be optionally arranged. The at least one cylindrical adsorber element 40 comprises a wide slot 34 so that the adsorber element 40 is not closed about the circumference, in particular comprises an open region of 10° to 45°, in particular of 20° to 30°.

[0065] As illustrated in an exemplary fashion in FIG. 8, the at least one acoustic component 30 and the at least one adsorber element 40 are arranged like a sleeve about the at least one section 14 of the inner pipe 10. For mounting the acoustic component 30 and the adsorber element 40 on the inner pipe 10, the components can be elastically bent open, for example, in order to be pushed thus radially or axially onto the inner pipe 10. After mounting, the slot 34 then closes again due to the inherent elasticity of the acoustic component 30 which is manufactured of plastic material, for example, as an injection molded part. In this way, the acoustic component 30 is arranged fixedly on the inner pipe 10. The radially outer acoustic component 30 fixes with form fit the adsorber element 40 in an advantageous embodiment.

[0066] The inner pipe 10 comprises openings 18 upstream and/or downstream of the section 14 along the longitudinal axis L which are acoustically connected with a volume 36 which is arranged between the inner pipe 10 and the inner wall 26 of the housing 20. The adsorber medium 42 can be provided in particular for adsorption of hydrocarbons (HO).

[0067] In an embodiment of the inner pipe according to FIGS. 7 and 8, an acoustic component 30 and an adsorber element 40 are provided in a first section 14 and a second section 15, respectively. Other embodiments with a deviating number of acoustic components and adsorber elements can be advantageous in other applications. Alternatively, the components can comprise different slot widths.

[0068] The air duct 100 according to the invention can be arranged in general at a clean air side of an air inlet of the internal combustion engine or at a raw air side of an air inlet of the internal combustion engine. At the clean air side, the air duct can be embodied without adsorber element.

[0069] According to a beneficial embodiment of the air duct, the adsorber medium can comprise at least one active carbon-containing 66 layer, comprising a gas-permeable carrier layer 64 on which an active carbon layer 66 is arranged. In particular, the active carbon layer 66 can be covered with a gas-permeable holding layer 68.

[0070] The active carbon layer 62 can be formed by a fluid-permeable adhesive layer 70 on which active carbon particles are applied. Advantageously, the adsorber medium can be formed by a plurality of such layers 66. The number of the layers can be selected as needed.

[0071] Advantageously, the active carbon layer can be covered with a gas-permeable holding layer 68. In this way, the active carbon layer can be fixed safely on the carrier layer and can build a self-supporting active carbon-containing layer.