Cleaning apparatus with flow deflection element with mode filter

Patent metadata

Field	Value
Publication number	US-12433460-B2
Application number	US-202418647375-A
Country	US
Kind code	B2
Filing date	Apr 26, 2024
Priority date	Oct 28, 2021
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

A cleaning apparatus is provided, including at least one noise source and an air guidance device having at least one flow deflection element, wherein the at least one flow deflection element has a first duct arm and a second duct arm, wherein the second duct arm is oriented transversely to the first duct arm, and wherein, during operation of the cleaning apparatus, there is sound propagation from the first duct arm to the second duct arm, wherein a mode filter device for transverse modes of sound propagation is arranged at the at least one flow deflection element, having at least one mode filter that is positioned at the second duct arm.

First claim

The invention claimed is:

1. A cleaning apparatus, comprising at least one noise source and an air guidance device having at least one flow deflection element, wherein the at least one flow deflection element has a first duct arm, having a first duct arm depth, and a second duct arm, having a second duct arm depth, wherein the first duct arm depth and the second duct arm depth are equal to one another, wherein the second duct arm is oriented transversely to the first duct arm at a right angle, and wherein, during operation of the cleaning apparatus, there is sound propagation from the first duct arm to the second duct arm, and at a transition region from the first duct arm to the second duct arm transverse modes of sound propagation arise, wherein a mode filter device for transverse modes of sound propagation is arranged at the at least one flow deflection element, having at least one mode filter that is positioned at the second duct arm, such that a spacing of the at least one mode filter which is arranged at the second duct arm is at least 0.1 times a first width of the first duct arm in a first width direction or a second width of the second duct arm in a second width direction, wherein the spacing is parallel to a first width direction and relates to a side of the first duct arm that lies at an internal corner region of the at least one flow deflection element.

2. The cleaning apparatus as claimed in claim 1 , wherein the at least one flow deflection element has a sound deflection region for sound propagation from the first duct arm to the second duct arm, and wherein in respect of sound propagation at least one mode filter for transverse modes is arranged downstream of the sound deflection region.

3. The cleaning apparatus as claimed in claim 1 , wherein at least one of the following applies:
the at least one mode filter which is positioned at the second duct arm is at a spacing from a sound deflection region;
the at least one mode filter which is positioned at the second duct arm is at a spacing from the first duct arm;
a spacing of the at least one mode filter which is arranged at the second duct arm is at least 0.1 times a first width of the first duct arm in a first width direction or a second width of the second duct arm in a second width direction, wherein the spacing is parallel to a first width direction and relates to a side of the first duct arm that lies at an internal corner region of the at least one flow deflection element.

4. The cleaning apparatus as claimed in claim 1 , wherein the mode filter device comprises at least one mode filter for transverse modes which is arranged at the first duct arm.

5. The cleaning apparatus as claimed in claim 1 , wherein the first duct arm has a first opening that extends in a first width direction and a first depth direction, wherein the first depth direction is perpendicular to the first width direction, and wherein the second duct arm has a second opening that extends in a second width direction and a second depth direction perpendicular to the second width direction, having at least one of the following:
the first width direction and the second width direction are transverse and in particular perpendicular to one another;
the first depth direction and the second depth direction are at least approximately parallel to one another;
the first depth direction and the second width direction are perpendicular to one another;
the second depth direction and the first width direction are perpendicular to one another.

6. The cleaning apparatus as claimed in claim 5 , wherein, during the propagation of sound through the at least one flow deflection element during operation of the cleaning apparatus, transverse modes that propagate in the first width direction and second width direction and transverse modes that propagate in the first depth direction and second depth direction may fundamentally be formed.

7. The cleaning apparatus as claimed in claim 5 , wherein the at least one mode filter at the second duct arm takes a form for filtering transverse modes in the second width direction.

8. The cleaning apparatus as claimed in claim 1 , wherein a mode filter of the mode filter device for transverse modes is or comprises at least one of the following:
an absorptive sound attenuator;
a chamber-type sound attenuator;
a perforated device that is positioned in an interior of the at least one flow deflection element.

9. The cleaning apparatus as claimed in claim 8 , wherein the absorptive sound attenuator has material that is absorptive in relation to sound and is in particular arranged as an absorptive layer.

10. The cleaning apparatus as claimed in claim 9 , wherein the absorptive material is flush with an inner side of the at least one flow deflection element, or is set back in relation to an inner side of the at least one flow deflection element.

11. The cleaning apparatus as claimed in claim 9 , wherein the absorptive sound attenuator has at least one of the following parameters:
a thickness of the absorptive material is at least 0.1 times a width of the first duct arm or the second duct arm;
a length of the absorptive sound attenuator parallel to a direction of extent of the duct arm at which the absorptive sound attenuator is arranged is at least 1.5 times a width of the first duct arm or the second duct arm;
a spacing of the absorptive sound attenuator that is arranged at the second duct arm from the first duct arm is at least 0.1 times a width of the first duct arm or the second duct arm.

12. The cleaning apparatus as claimed in claim 7 , wherein the chamber-type sound attenuator has a chamber that forms a widening in cross section at the duct arm at which the chamber-type sound attenuator is arranged.

13. The cleaning apparatus as claimed in claim 12 , wherein the chamber-type sound attenuator has at least one of the following parameters:
a width of the chamber is at least twice a width of the first duct arm or the second duct arm;
a length of the chamber-type sound attenuator parallel to a direction of extent of the duct arm at which the chamber-type sound attenuator is arranged is at least 1.2 times a width of the first duct arm and the second duct arm;
a spacing of the chamber-type sound attenuator that is arranged at the second duct arm from the first duct arm is at least 0.1 times a width of the first duct arm or the second duct arm.

14. The cleaning apparatus as claimed in claim 8 , wherein the absorptive sound attenuator or the chamber-type sound attenuator or the perforated device takes a form for attenuation of transverse modes only in a width direction.

15. The cleaning apparatus as claimed in claim 8 , wherein, in the case of the perforated device, at least one of the following is present:
openings in the perforated device have an opening width of less than or equal to 1 mm;
an opening density is greater than or equal to 10 openings per square centimeter;
a wall thickness of the perforated device in a width direction of the duct arm at which the perforated device is arranged is at least 1 mm.

16. The cleaning apparatus as claimed in claim 8 , wherein at least one of the following applies:
the perforated device is or comprises one or more plates provided with openings;
the perforated device comprises one or more open-pore structures;
an open-pore structure takes the form of a block;
an open-pore structure is a foam structure and in particular at least one of (i) an absorbent foam structure and (ii) a fiber material structure.

17. The cleaning apparatus as claimed in claim 1 , wherein the first du

Assignees

• Kaercher Alfred Se & Co Kg

Inventors

• Scholl Dominik
• Ebert Florian

Classifications

• G10K11/172

  using resonance effects · CPC title

• F24F13/24

  Means for preventing or suppressing noise · CPC title

• A47L11/4097

  Means for exhaust-air diffusion; Exhaust-air treatment, e.g. air purification; Means for sound or vibration damping · CPC title

• A47L9/0081 Primary

  Means for exhaust-air diffusion; Means for sound or vibration damping · CPC title