Tubular acoustic silencer

• US 7,497,301 B2
• Filed: 08/10/2005
• Issued: 03/03/2009
• Est. Priority Date: 01/27/2005
• Status: Active Grant

• Current Assignee: Cummins Filtration Incorporated (Cummins Incorporated)
• Original Assignee: Fleetguard, Inc. (Cummins Incorporated)
• Inventors: Cheng, C. Raymond, Quabili, Zakir Ahmad, Gunderson, Larry T., Holzmann, Mark V.
• Primary Examiner(s): San Martin; Edgardo
• Application Number:
  US11/201,390
• Publication Number:
  US 20060180389A1
• Time in Patent Office: 1,301 Days
• Field of Search: 181/248, 181/250, 181/266, 181/270, 181/273, 181/276, 181/293
• US Class Current: 181/248
• CPC Class Codes: B01D 46/0045 by using vanes
• CPC Class Codes: B01D 46/2414 End caps including additional functions or special forms
• CPC Class Codes: F02M 35/1211 by using inserts in the air intake flow path, e.g. baffles, throttles or orifices; Flow guides F02M35/1244 takes precedence
• CPC Class Codes: F02M 35/1216 by using a plurality of holes, slits, protrusions, perforations, ribs or the like; Surface structures; Turbulence generators
• CPC Class Codes: F02M 35/1255 using resonance
• CPC Class Codes: F02M 35/14 Combined air cleaners and silencers

Abstract

An acoustic silencer is provided by a tubular member extending along an axis and having a hollow interior defining an axial flow path therethrough. The tubular member has a sidewall with an interior face facing the hollow interior and having quarter wave resonators formed by blind holes therein.

Claims

1. An acoustic silencer comprising a tubular member extending along an axis and having a hollow interior defining an axial flow path therethrough, said tubular member having a sidewall with an interior face facing said hollow interior and having quarter wave resonators formed by blind holes therein, wherein said tubular member comprises an outer sleeve and an inner liner engaging each other in abutting relation, said quarter wave resonators being formed by holes extending outwardly through said inner liner and terminating at said outer sleeve to form said blind holes, and wherein said inner liner comprises a pair of symmetrical halves.

2. An acoustic silencer comprising a tubular member extending along an axis and having a hollow interior defining an axial flow path therethrough, said tubular member having a sidewall with an interior face facing said hollow interior and having quarter wave resonators formed by blind holes therein, wherein said interior face of said sidewall has a first set of one or more quarter wave resonator blind holes of a first size, and one or more additional sets of one or more quarter wave resonator blind holes of a different size, for attenuation of different frequencies, wherein said first set of blind holes have a first depth, and comprising a second said additional set of one or more quarter wave resonator blind holes having a second depth less then said first depth, and wherein said tubular member comprises an outer sleeve and an inner liner engaging each other in abutting relation, said inner liner having a first section of a first radial wall thickness, said inner liner having a second section of a second radial wall thickness less than said first radial wall thickness, said first section having a first set of one or more holes extending outwardly therethrough and terminating at said outer sleeve to form said first set of one or more quarter wave resonator blind holes of said first depth, said second section having a second set of one or more holes extending outwardly therethrough and terminating at said outer sleeve to form said second set of one or more quarter wave resonator blind holes of said second depth.

3. The acoustic silencer according to claim 2 wherein:

said inner liner has a variable outer circumference of varying outer diameter, including a first portion having a first outer diameter providing said first section of said inner liner of said first radial wall thickness, and a second portion having a second outer diameter providing said second section of said inner liner of said second radial wall thickness, said second outer diameter being less than said first outer diameter;

said outer sleeve has a variable inner circumference of varying inner diameter, including a first portion having a first inner diameter at said first section of said inner liner, and a second portion having a second inner diameter at said second section of said inner liner, said second inner diameter being less than said first inner diameter.

4. The acoustic silencer according to claim 3 wherein said outer circumference of said inner liner and said inner circumference of said outer sleeve vary in step-change manner.

5. The acoustic silencer according to claim 3 wherein said outer circumference of said inner liner and said inner circumference of said outer sleeve vary in tapered relation.

6. The acoustic silencer according to claim 5 wherein each of said outer circumference of said inner liner and said inner circumference of said outer sleeve vary along a taper providing variable depth quarter wave resonator blind holes.

7. An acoustic silencer comprising a tubular member extending along an axis and having a hollow interior defining an axial flow path therethrough, said tubular member having a sidewall with an interior face facing said hollow interior and having quarter wave resonators formed by blind holes therein, wherein said interior face has first, second and third sets of one or more quarter wave resonator blind holes, said first set having a first depth, said second set having a second depth, said third set having a third depth, said third depth being less than said second depth, said second depth being less than said first depth, said tubular member comprising an outer sleeve and an inner liner engaging each other in abutting relation, said inner liner having a first section of a first radial wall thickness, a second section of a second radial wall thickness less than said first radial wall thickness, and a third section of a third radial wall thickness less than said second radial wall thickness, said first section having a first set of one or more holes extending outwardly therethrough and terminating at said outer sleeve to form said first set of one or more quarter wave resonator blind holes of said first depth, said second section having a second set of one or more holes extending outwardly therethrough and terminating at said outer sleeve to form said second set of one or more quarter wave resonator blind holes of said second depth, said third section having a third set of one or more holes extending outwardly therethrough and terminating at said outer sleeve to form said third set of one or more quarter wave resonator blind holes of said third depth, said inner liner having a variable outer circumference of varying outer diameter, including a first portion having a first outer diameter providing said first section of said inner liner of said first radial wall thickness, a second portion having a second outer diameter providing said second section of said inner liner of said second radial wall thickness, and a third portion having a third outer diameter providing said third section of said inner liner of said third radial wall thickness, said third outer diameter being less than said second outer diameter, said second outer greater diameter being less than said first outer diameter, said outer sleeve having a variable inner circumference of varying inner diameter, including a first portion having a first inner diameter at said first section of said inner liner, a second portion having a second inner diameter at said second section of said inner liner, and a third portion having a third inner diameter at said third section of said inner liner, said third inner diameter being less than said second inner diameter, said second inner diameter being less than first inner diameter.