US2809709A - Silencer - Google Patents

Silencer Download PDF

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Publication number
US2809709A
US2809709A US522292A US52229255A US2809709A US 2809709 A US2809709 A US 2809709A US 522292 A US522292 A US 522292A US 52229255 A US52229255 A US 52229255A US 2809709 A US2809709 A US 2809709A
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Prior art keywords
chamber
housing
exhaust
outlet
section
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Expired - Lifetime
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US522292A
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Leino H Billey
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Donaldson Co Inc
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Donaldson Co Inc
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Priority to US522292A priority Critical patent/US2809709A/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N1/00Silencing apparatus characterised by method of silencing
    • F01N1/003Silencing apparatus characterised by method of silencing by using dead chambers communicating with gas flow passages
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N1/00Silencing apparatus characterised by method of silencing
    • F01N1/08Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
    • F01N1/084Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling the gases flowing through the silencer two or more times longitudinally in opposite directions, e.g. using parallel or concentric tubes

Definitions

  • Claim. (Cl. 181-54)
  • My invention relates generally to improvements in a silencer for a gaseous medium. It has been found particularly useful in silencing the exhaust gases of internal combustion engines; and it is in particular a silencing device of the type generally known as mutliers.
  • the gaseous medium discharged from the exhaust of internal combustion engines is subject to pressure pulsations which produce very objectionable noises unless attenuated or silenced in some manner before the gaseous medium is discharged to atmosphere.
  • Mufflers are inserted in the exhaust conduits of such engines to accomnited States Patent O 2,809,709 Patented Oct. 15, 1957 ICC "' of these, chamber 14 is defined as the front end chamber and chamber 21 is defined as the rear-end chamber.
  • I provide an elongated exhaust conduit means, indicated generally by the numeral 22, which is preferably made up primarily of tubular sections 23, 24, 25 and Y 26.
  • Section 23 forms an inlet end 27 of conduit means plish attenuation or effective silencing of the exhaust gases and this is their primary function.
  • a principal object of my invention is to provide a novel and improved silencer or muffler construction which produces more effective attenuation or effective silencing of the exhaust gases than mufflers now known; and yet provide a muffler which is of simple design and construction.
  • exhaust mufflers for a vehicle are constructed with an end outlet which is coupled to and opens axially rearwardly into an elongated, axially extending member, commonly referred to as a tail pipe.
  • Fig. l is a view in axial section of my invention.
  • Fig. 2 is a view partly in vertical section and partly in elevation taken on the line 2 2 of Fig. 1.
  • my invention comprises an elongated tubular housing or outer shell 10 having opposite end walls 11 and 12. Longitudinally spaced transverse partitions 13, together with end walls 11 and 12, divide the interior of housing 10 into a plurality of longitudinally aligned chambers, indicated by the numerals 14-21.
  • One of the intermediate chambers, and specifically chamber 19, has an outlet therefrom; and chamber 19 is defined as an outlet chamber.
  • the remaining chambers are closed chambers; and
  • Inlet end 27 opens axially outwardly in axially outwardly spaced relation to end wall 11; and section 23 projects from inlet end 27 through end wall 11 axially into the housing 10 to terminate at its opposite open end in one of the intermediate chambers.
  • section 23 extends completely through front end chamber 14 and extends into intermediate closed chamber 15.
  • Tubular section 24 extends from intermediate chamber 15 completely through intermediate chamber 16 into chamber 17.
  • Section 24 is in offset, generally laterally spaced parallel relationship with section 23 so that adjacent ends of sections 23 and 24 which extend into the same closed chamber 15 provide what is known as an S gap therebetween.
  • Section 25 extends from intermediate chamber 17 to terminate in rear end chamber 21, and is in longitudinally spaced generally axially aligned relationship with section 23; wherein the adjacent ends of sections 24 and 25 in the common intermediate chamber 17 are spaced and offset to provide a similar S gap.
  • Tubular section 26 is disposed in laterally spaced generally parallel relationship to section 25 and extends from rear end chamber 21 through intermediate chamber 20 to terminate adjacent the partition 13 dividing chambers 19 and 20 with its end opening into outlet chamber 19.
  • conduit means 22 defines an exhaust passageway from inlet end 27 axially through the housing 10 to rear end chamber 21 and then in the opposite direction from rear end chamber 21 back to outlet chamber 19.
  • Housing 10 has a lateral opening 23 formed in its side wall which communicates with outlet chamber 19 to provide an outlet therefrom.
  • I provide a laterally outwardly projecting rearwardly opening snout, indicated generally by the reference numeral 29, which is anchored to housing 10 adjacent the lateral opening 28 and in communication with outlet chamber 19 through opening 28.
  • snout 29 projects through opening 28 and adjoins housing 10 about the periphery of opening 28 and is rigidly anchored to housing 10 at such adjoining points by welding or the like.
  • snout 29 is elbow-like and defines a passageway having an inlet 30 opening laterally inwardly into outlet chamber 19 and having a generally rearwardly opening discharge aperture 31 leading to atmosphere laterally outwardly of housing 10.
  • Snout 29 comprises an arcuate front wall 32 extending between the inlet opening 30 and the discharge aperture 31 thereof, and a pair of laterally spaced parallel generally flat side walls 33, each of generally pie-shaped forni.
  • Arcuate front wall 32 acts to smoothly direct the gaseous medium through snout 29 from outlet chamber 19 to discharge rearwardly to atmosphere.
  • Side walls 33 are preferably formed integrally with arcuate front wall 32.
  • the passages are preferably arranged in a multiple perforation pattern similar to that described and claimed in my co-pending application, Serial Number 439,67() tiled on June 28, 1954.
  • my novel and improved muiller with snout 29 providing an exhaust outlet from an intermediate outlet chamber permits the iength ot the muwerr to be held down to a minimum and it eliminates the customarily used tail pipe, generally extending rearwardly beyond the ordinary muttier construction.
  • the tail pipe of the ordinary muter construction is often in need of repair and replacements so that its elimination is very advair tageous.
  • My mutller construction is adapted to be connected in the exhaust conduit or" an internal combustion engine of a vehicle so that snout 29 diverts and disperses the exhaust gases and sound'sideways and down underneath the vehicle chassis which :uds in effecting the attenuation of the sound or noise. Further, the positioning of my muanderr keeps exhaust heat away from the right rear tire and air brake diaphragm chamber which is not true of muter constructions now generaly known.
  • exhaust conduit means 22 which is basically of the type characterized as a 2S gap extended range mutiier, is not required, but it may be modified in many respects.
  • exhaust conduit means 22 between its inlet end 27 and rear end chamber 21 might comprise a single straight through section or longitudinally spaced sections providing a straight gap rather than an S gap.
  • communication between sections 25 and 26 of conduit means 22 might be accomplished by a C shaped connecting section or the like, instead of the C gap shown in Fig. 1.
  • the number of chambers formed in housing iti is not critical but may be varied in many respects. It will be obvious to those skilled in the art that my invention may be modiiied by many substitutions and equivalents and that this disclosure is intended to be illustrative only; therefore, I
  • a silencer for a gaseous medium an elongated housing having opposite end Walls, transverse partition means dividing the interior of said housing into front and rear end chambers and intermediate chambers, one of said intermediate chambers dening an outlet chamber, said housing having a lateral opening through its side wall providing an outlet from said outlet chamber, a laterally outwardly projecting elbowike snout anchored to said hOus ing adjacent said lateral opening and deiining a discharge passageway opening laterally inwardly at one end into said outlet chamber and having a generally rearwardly opening discharge aperture to atmosphere, and an elongated exhaust conduit means having an inlet end extending through the housing end wall adjoining the front end chamber, said conduit means extending axially within said housing through said partition means from said inlet end to said rear end chamber and from said rear end chamber to said outlet chamber and terminating in and opening into said outlet chamber, that portion ot said conduit means between said rear end chamber and the inlet end thereof which is enclosed within said outlet chamber being imperlorate and

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Silencers (AREA)

Description

L. H. BILLEY Oct. 15, 1957 SILENCER Filed July l5, 1955 INVENToR.
Aa/Vfyf jef/za O O DMVDOIm-u O .000000 SILENCER Leine H. Billey, St. Pani, Minn., assignor to Donaldson Company, Inc., St. Paul, Minn., a corporation of Delaware Application July 15, 1955, Serial No. 522,292
1 Claim. (Cl. 181-54) My invention relates generally to improvements in a silencer for a gaseous medium. It has been found particularly useful in silencing the exhaust gases of internal combustion engines; and it is in particular a silencing device of the type generally known as mutliers.
The gaseous medium discharged from the exhaust of internal combustion engines is subject to pressure pulsations which produce very objectionable noises unless attenuated or silenced in some manner before the gaseous medium is discharged to atmosphere. Mufflers are inserted in the exhaust conduits of such engines to accomnited States Patent O 2,809,709 Patented Oct. 15, 1957 ICC "' of these, chamber 14 is defined as the front end chamber and chamber 21 is defined as the rear-end chamber.
I provide an elongated exhaust conduit means, indicated generally by the numeral 22, which is preferably made up primarily of tubular sections 23, 24, 25 and Y 26. Section 23 forms an inlet end 27 of conduit means plish attenuation or effective silencing of the exhaust gases and this is their primary function. As more and more vehicles such as automobiles, buses and trucks are being used today, particularly in city areas, so that there is a great deal of congested vehicle traffic, it becomes essential that a maximum degree of silencing of the exhaust gases from these vehicles is effected.
A principal object of my invention is to provide a novel and improved silencer or muffler construction which produces more effective attenuation or effective silencing of the exhaust gases than mufflers now known; and yet provide a muffler which is of simple design and construction.
Generally, exhaust mufflers for a vehicle are constructed with an end outlet which is coupled to and opens axially rearwardly into an elongated, axially extending member, commonly referred to as a tail pipe.
Further objectives of my invention are to provide a novel and improved silencer or mufer construction having a side outlet and which:
(l) Diverts and disperses the exhaust gases and sound sideways and down underneath the vehicle chassis;
(2) Permits the length of the muffler to be held to a minimum due to elimination of the end outlet;
(3) Keeps exhaust heat away from the right rear tire and air brake diaphragm chamber; and
(4) Eliminates the tail pipe customarily coupled to a muffler.
The above and other objectives and advantages of my invention will become apparent from the following specification and claims, reference being had to the accompanying drawings wherein:
Fig. l is a view in axial section of my invention; and
Fig. 2 is a view partly in vertical section and partly in elevation taken on the line 2 2 of Fig. 1.
Referring more particularly to the drawings, wherein like parts will be indicated by the same numerals, my invention comprises an elongated tubular housing or outer shell 10 having opposite end walls 11 and 12. Longitudinally spaced transverse partitions 13, together with end walls 11 and 12, divide the interior of housing 10 into a plurality of longitudinally aligned chambers, indicated by the numerals 14-21. One of the intermediate chambers, and specifically chamber 19, has an outlet therefrom; and chamber 19 is defined as an outlet chamber. The remaining chambers are closed chambers; and
22. Inlet end 27 opens axially outwardly in axially outwardly spaced relation to end wall 11; and section 23 projects from inlet end 27 through end wall 11 axially into the housing 10 to terminate at its opposite open end in one of the intermediate chambers. Specifically section 23 extends completely through front end chamber 14 and extends into intermediate closed chamber 15. Tubular section 24 extends from intermediate chamber 15 completely through intermediate chamber 16 into chamber 17. Section 24 is in offset, generally laterally spaced parallel relationship with section 23 so that adjacent ends of sections 23 and 24 which extend into the same closed chamber 15 provide what is known as an S gap therebetween. Section 25 extends from intermediate chamber 17 to terminate in rear end chamber 21, and is in longitudinally spaced generally axially aligned relationship with section 23; wherein the adjacent ends of sections 24 and 25 in the common intermediate chamber 17 are spaced and offset to provide a similar S gap. Tubular section 26 is disposed in laterally spaced generally parallel relationship to section 25 and extends from rear end chamber 21 through intermediate chamber 20 to terminate adjacent the partition 13 dividing chambers 19 and 20 with its end opening into outlet chamber 19.
- The adjacent open ends of sections 25 and 26 in rear end chamber 21 provide a C gap therebetween. The direction of flow through the silencer or muffler is indicated by fiow arrows on Fig. l; and it will be understood that the inlet end 27 is adapted to be coupled in or formed as an integral part of the exhaust pipe of an engines exhaust system. As the ow arrows indicate, conduit means 22 defines an exhaust passageway from inlet end 27 axially through the housing 10 to rear end chamber 21 and then in the opposite direction from rear end chamber 21 back to outlet chamber 19.
Housing 10 has a lateral opening 23 formed in its side wall which communicates with outlet chamber 19 to provide an outlet therefrom. I provide a laterally outwardly projecting rearwardly opening snout, indicated generally by the reference numeral 29, which is anchored to housing 10 adjacent the lateral opening 28 and in communication with outlet chamber 19 through opening 28. Preferably, snout 29 projects through opening 28 and adjoins housing 10 about the periphery of opening 28 and is rigidly anchored to housing 10 at such adjoining points by welding or the like. Preferably, snout 29 is elbow-like and defines a passageway having an inlet 30 opening laterally inwardly into outlet chamber 19 and having a generally rearwardly opening discharge aperture 31 leading to atmosphere laterally outwardly of housing 10. Snout 29 comprises an arcuate front wall 32 extending between the inlet opening 30 and the discharge aperture 31 thereof, and a pair of laterally spaced parallel generally flat side walls 33, each of generally pie-shaped forni. Arcuate front wall 32 acts to smoothly direct the gaseous medium through snout 29 from outlet chamber 19 to discharge rearwardly to atmosphere. Side walls 33 are preferably formed integrally with arcuate front wall 32.
That portion of renduit means 22 between rear end chamber 21 and inlet end 2T" which is enclosed within outlet chamber 19, which is that portion of that section 25 indicated by the numeral 34, is imperforate; however, the remaining portions of sections 23, 24, 25 and 2'5 of conduit means 22 are provided with a plurality of passages leading through the walls hereof int-o the adjoining closed chambers, which dene resonance or attenuating chambers. The passages are preferably arranged in a multiple perforation pattern similar to that described and claimed in my co-pending application, Serial Number 439,67() tiled on June 28, 1954.
The construction of my novel and improved muiller with snout 29 providing an exhaust outlet from an intermediate outlet chamber permits the iength ot the muiiler to be held down to a minimum and it eliminates the customarily used tail pipe, generally extending rearwardly beyond the ordinary muttier construction. The tail pipe of the ordinary muter construction is often in need of repair and replacements so that its elimination is very advair tageous. My mutller construction is adapted to be connected in the exhaust conduit or" an internal combustion engine of a vehicle so that snout 29 diverts and disperses the exhaust gases and sound'sideways and down underneath the vehicle chassis which :uds in effecting the attenuation of the sound or noise. Further, the positioning of my muiiler keeps exhaust heat away from the right rear tire and air brake diaphragm chamber which is not true of muter constructions now generaly known.
It is clear that the speciiic construction of the exhaust conduit means 22 shown in the drawings, which is basically of the type characterized as a 2S gap extended range mutiier, is not required, but it may be modified in many respects. For example, exhaust conduit means 22 between its inlet end 27 and rear end chamber 21 might comprise a single straight through section or longitudinally spaced sections providing a straight gap rather than an S gap. Further, communication between sections 25 and 26 of conduit means 22 might be accomplished by a C shaped connecting section or the like, instead of the C gap shown in Fig. 1. In addition, it is clear that the number of chambers formed in housing iti is not critical but may be varied in many respects. It will be obvious to those skilled in the art that my invention may be modiiied by many substitutions and equivalents and that this disclosure is intended to be illustrative only; therefore, I
intend to be limited solely by the scope of the appended claim.
What I claim is:
ln a silencer for a gaseous medium, an elongated housing having opposite end Walls, transverse partition means dividing the interior of said housing into front and rear end chambers and intermediate chambers, one of said intermediate chambers dening an outlet chamber, said housing having a lateral opening through its side wall providing an outlet from said outlet chamber, a laterally outwardly projecting elbowike snout anchored to said hOus ing adjacent said lateral opening and deiining a discharge passageway opening laterally inwardly at one end into said outlet chamber and having a generally rearwardly opening discharge aperture to atmosphere, and an elongated exhaust conduit means having an inlet end extending through the housing end wall adjoining the front end chamber, said conduit means extending axially within said housing through said partition means from said inlet end to said rear end chamber and from said rear end chamber to said outlet chamber and terminating in and opening into said outlet chamber, that portion ot said conduit means between said rear end chamber and the inlet end thereof which is enclosed within said outlet chamber being imperlorate and other portions of said conduit means being provided with a plurality of passages leading through the walls thereof into said chambers.
References Cited in the tile of this patent UNITED STATES PATENTS 1,468,895 Allan Sept. 25, 1923 2,255,579 Blanchard Sept. 9, 1941 2,357,791 Powers Sept. 5, 1944 2,618,354 Hedrick Nov. 18, 1952 2,661,073 Deremer Dec. 1, 1953 FOREIGN PATENTS 339,770 Great Britain Dec. 18, 1930
US522292A 1955-07-15 1955-07-15 Silencer Expired - Lifetime US2809709A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3114430A (en) * 1961-03-06 1963-12-17 Burgess Manning Co Pulsation snubber or silencer
US4203502A (en) * 1978-08-28 1980-05-20 Strader Walter F Muffler
US4267899A (en) * 1979-08-31 1981-05-19 Donaldson Company, Inc. Muffler assembly
US6082487A (en) * 1998-02-13 2000-07-04 Donaldson Company, Inc. Mufflers for use with engine retarders; and methods
US6148519A (en) * 1998-09-18 2000-11-21 Donaldson Company, Inc. Apparatus for installing a packing material in a muffler assembly; and methods thereof
US6354398B1 (en) 1998-02-13 2002-03-12 Donaldson Company, Inc. Mufflers for use with engine retarders; and methods
US8820475B2 (en) 2012-12-05 2014-09-02 Caterpillar Inc. Exhaust muffler
US20170218806A1 (en) * 2016-02-02 2017-08-03 Kohler Co. Muffler

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1468895A (en) * 1921-11-15 1923-09-25 Allan Ronald Gordon Silencer for use in connection with internal-combustion engines
GB339770A (en) * 1929-11-26 1930-12-18 Bentley Motors Ltd Silencers for fluid-pressure engines
US2255579A (en) * 1938-11-14 1941-09-09 Cecil Gordon Vokes Exhaust silencer
US2357791A (en) * 1941-03-24 1944-09-05 Walker Mfg Company Of Wisconsi Silencer
US2618354A (en) * 1948-06-14 1952-11-18 Maremont Automotive Products I Retroverted passage type muffler with expansion chambers
US2661073A (en) * 1950-08-09 1953-12-01 Oldberg Mfg Company Silencer or muffler

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1468895A (en) * 1921-11-15 1923-09-25 Allan Ronald Gordon Silencer for use in connection with internal-combustion engines
GB339770A (en) * 1929-11-26 1930-12-18 Bentley Motors Ltd Silencers for fluid-pressure engines
US2255579A (en) * 1938-11-14 1941-09-09 Cecil Gordon Vokes Exhaust silencer
US2357791A (en) * 1941-03-24 1944-09-05 Walker Mfg Company Of Wisconsi Silencer
US2618354A (en) * 1948-06-14 1952-11-18 Maremont Automotive Products I Retroverted passage type muffler with expansion chambers
US2661073A (en) * 1950-08-09 1953-12-01 Oldberg Mfg Company Silencer or muffler

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3114430A (en) * 1961-03-06 1963-12-17 Burgess Manning Co Pulsation snubber or silencer
US4203502A (en) * 1978-08-28 1980-05-20 Strader Walter F Muffler
US4267899A (en) * 1979-08-31 1981-05-19 Donaldson Company, Inc. Muffler assembly
US6082487A (en) * 1998-02-13 2000-07-04 Donaldson Company, Inc. Mufflers for use with engine retarders; and methods
US6354398B1 (en) 1998-02-13 2002-03-12 Donaldson Company, Inc. Mufflers for use with engine retarders; and methods
US6148519A (en) * 1998-09-18 2000-11-21 Donaldson Company, Inc. Apparatus for installing a packing material in a muffler assembly; and methods thereof
US8820475B2 (en) 2012-12-05 2014-09-02 Caterpillar Inc. Exhaust muffler
US20170218806A1 (en) * 2016-02-02 2017-08-03 Kohler Co. Muffler
US10196947B2 (en) * 2016-02-02 2019-02-05 Kohler Co. Muffler

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