US3779342A - Engine noise depressing assemblies - Google Patents

Engine noise depressing assemblies Download PDF

Info

Publication number
US3779342A
US3779342A US00301178A US3779342DA US3779342A US 3779342 A US3779342 A US 3779342A US 00301178 A US00301178 A US 00301178A US 3779342D A US3779342D A US 3779342DA US 3779342 A US3779342 A US 3779342A
Authority
US
United States
Prior art keywords
engine
tubular sleeve
exhaust port
baffle plates
noise
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00301178A
Other languages
English (en)
Inventor
D Broberg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3779342A publication Critical patent/US3779342A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features
    • F01N13/18—Construction facilitating manufacture, assembly, or disassembly
    • F01N13/1838—Construction facilitating manufacture, assembly, or disassembly characterised by the type of connection between parts of exhaust or silencing apparatus, e.g. between housing and tubes, between tubes and baffles
    • F01N13/1844—Mechanical joints
    • F01N13/1855—Mechanical joints the connection being realised by using bolts, screws, rivets or the like
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N1/00—Silencing apparatus characterised by method of silencing
    • F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/34—Ultra-small engines, e.g. for driving models
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B9/00—Engines characterised by other types of ignition
    • F02B9/06—Engines characterised by other types of ignition with non-timed positive ignition, e.g. with hot-spots
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2450/00—Methods or apparatus for fitting, inserting or repairing different elements
    • F01N2450/24—Methods or apparatus for fitting, inserting or repairing different elements by bolts, screws, rivets or the like
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S181/00—Acoustics
    • Y10S181/404—Hobby craft engine muffler

Definitions

  • ABSTRACT Noise depressing devices are provided for use in conjunction with engines of the type commonly used to power model aircraft, boats, cars and the like.
  • the noise depressing devices include: (1) an elongated extension sleeve that is secured to and aligns at one of its ends with the exhaust port of an engine and (2) a plurality of spaced baffle plates secured to the opposite end of the sleeve that are designed to quietly diffuse the exhaust gases into the atmosphere.
  • the present invention relates generally to noise depressing devices and more specifically to light-weight, simplified mufflers useful in reducing exhaust engine noises emitted from engines of the type commonly used to power miniature aircraft, cars, boats and models.
  • exhaust engine noises are depressed by means of a muffler assembly in which an elongated, hollow extension sleeve is secured to the exhaust portion of the engine and a plurality of spaced baffle plates are secured to the opposite end of the elongated extension sleeve.
  • Exhaust gases discharging from the engine exhaust port therefore, pass through the elongated extension sleeve and then diffuse in a quiet fashion through the spaces formed between the spaced, parallel aligned baffle plates.
  • FIG. I is a side elevational view of an engine and muffler assembly embodiment of this invention with the muffler assembly shown in cross-section.
  • FIG. 2 is a top plan view of an engine and muffler assembly illustrated in FIG. 1 with both the engine and muffler being shown in cross-section.
  • FIG. 3 is an elevational view of the upper portion of an engine and mufiler assembly showing a modified system for mounting the muffler onto the engine.
  • FIG. 4 is a cross-sectional view of the engine and muffler illustrated in FIG. 3 taken across line 4-4.
  • FIG. 5 is a fragmentary perspective view of the various bafile plates and spacers used at the outermost end of the muffler assembly.
  • FIG. 6 is a perspective view of an alignment adaptor plate or position key used in the engine and muffler embodiments illustrated in FIGS. 1 and 2 which is used to easily adapt the mufiler assembly to differently sized exhaust port openings for differently sized engines.
  • FIG. 7 is a diagramatic top plane view of the muffler assembly illustrated in FIGS. 1 and 2 with the various parts of the muffler in an unassembled state.
  • FIGS. 1 and 2 one embodiment of a noise depressing device or muffler 10 of this invention is shown in an attached relationship with a conventional model airplane engine 12.
  • a noise depressing device or muffler 10 of this invention is shown in an attached relationship with a conventional model airplane engine 12.
  • muffler devices of this invention can be used with various types of engines, for purposes of illustration, only a standard two-cycle model airplane engine is shown in the drawings.
  • the type engines 12 used in conjunction with the muffler devices 10 of this invention are internal combustion engines having a crank-case 14, an upwardly projecting cylinder l6, and an elongated slot-like exhaust port 18 which projects laterally from one side of cylinder 16 and provides a discharge point for exhaust gases emitted from the engine.
  • Various other parts of a typical engine such as a carburetor, fuel line, throttle, or fuel adjustment rod and propeller, are not shown in the drawings since they are not needed to fully describe the parts and operation of the muffler systems of this invention.
  • the mufflers or noise depressing devices of this invention generally include an elongated exhaust port extension sleeve 21, which is secured at one end to engine exhaust port 18 by means of clamp band 23, and which also includes, at its opposite end, a plurality of spaced baffle plates 25, which are secured to sleeve 21 by means of assembly screws 27.
  • exhaust port extension sleeve 21 is hollow, is constructed from a tubular material and is adapted to mesh at one end with the exhaust port 18 of the engine.
  • sleeve 21 is firmly secured to engine 12 by means of clamp band 23 which extends around the periphery of upwardly projecting cylinder 16.
  • Worm screw 30 acts as a tightening device for clamp band 23, and is first turned in one direction to loosen clamp band 23 and permit it to be easily slipped over the top of cylinder 16 and then is turned in an opposite direction to tighten the muffler assembly and clamp band 23 in a firmly secure position when the extension sleeve 21 is in a meshed relationship with engine exhaust port 18.
  • baffle plates 25, disposed at the outermost end of sleeve 21, are maintained in a spaced relationship by means of spacing washers 32 which are placed between each adjacent plate 25.
  • spacing washers 32 By means of baffle plates 25 and spacing washers 32, a plurality of small openings 34 are provided in muffler 10. These openings 34, of course, permit exhaust gases discharging through sleeve 21 to diffuse in a controlled manner into the atmosphere when engine 12 is in operation and, thus, provide a muffling effect that drastically reduces the operational noise levels for the engine.
  • each baffle plate 25 is not only provided with a plurality of slots 40, which permit diffusion of the exhaust gases emitted from the engine 12, but each plate is also provided with a pair of oppositely disposed openings 41 through which assembly screws 27 pass.
  • End plate 42 which is placed at the outermost end of the spaced baffle plates 25, has no slots, but instead is designed to block the flow of exhaust gases and direct such flow only through slots 40 in plates 25 and, in turn, through openings 34 formed between the spaced baffle plates 25.
  • the muffler devices of this invention can be easily assembled, first by securing sleeve 21 in place by means of clamp band 23, next by aligning baffle plates 25 in a spaced adjacent relationship, with pairs of spacing washers 32 being used to maintain appropriate spacing between adjacent plates, and finally by passing assembly screws 27 through the openings 43 in end plate 42, through the first pair of washers 32, through the openings 41 in baffle plates 25, through another pair of washers 32 and so forth until the entire structure of baffle plates 25 and spacing washers 32 is assembled.
  • the opposite edges of sleeve 21 are provided with a pair of threaded holes 44 into which assembly screws 27 are tightened to secure the entire baffle plate assembly.
  • the muffler systems 10 of this invention be universally adaptable to fit nearly any conventional engine currently available. Since various available engines have differently sized exhaust ports 18, it is preferable in the practice of this invention to utilize a pair of alignment adaptor or position keys 50 which fit between engine exhaust port 18 and exhaust port extension sleeve 21. As a result of the tight fit and support provided by the keys 50 a tight sealing engagement of exhaust port 18 and sleeve 21 is achieved by the securing means.
  • One such adaptor key 50 useful in the practice of this invention is shown generally in FIG. 6.
  • the cross-shaped key 50 shown in FIG. 6 includes edges 51 and 52, which are designed to fit tightly within the confines of upper and lower walls 60 and 61 of sleeve 21 (FIG.
  • edges 53 and 54 which are designed to fit tightly within the upper and lower walls 63 and 64 of engine exhaust port 18. If, for example, a relatively narrow opening is provided by walls 63 and 64 of engine exhaust port 18, then edges 53 and 54 of key 50 can be filed down to an appropriate size to insure a tight seal and fit between the elongated sleeve 21 of muffler 10 and the exhaust port 18 of engine 12.
  • muffler assembly 10 can be secured to the engine by means of assembly screws 70, which fit through bores 71 in exhaust port 18 and are threadably engaged at 72 to elongated sleeve 21.
  • FIG. 7 illustrates diagramatically the entire muffler assembly-embodiment of FIGS. 1 and 2 in an unassembled state.
  • the series of baffle plates 25 are shown in an aligned, side-by-side relationship prior to assembly with spacing washers 32 interposed between each baffle plate.
  • two assembly screws 27 are provided to fit through the aligned baffle plates 25 and spacing washers 32 to secure the baffle assembly to sleeve 21.
  • lock washers are provided between assembly screws 27 and end plate 42 to insure that baffle plates 25 will not loosen during operation of the muffler assembly.
  • alignment adaptor keys 50 are provided to adapt the opening in exhaust port 18 with the opening in sleeve 21 to insure a gastight fit between sleeve 21 and exhaust port 18. It should also be noted, however, that an adaptor blank 81 having a varying size opening 82 can also be used in the practice of this invention to insure a gas-tight fit between sleeve 21 and exhaust port 18.
  • adaptor blank 81 is particularly useful in the practice of this invention when opening in exhaust port 18 is substantially smaller than the opening in sleeve 21.
  • opening 82 in blank 81 is sized exactly to correspond to the opening in exhaust port 18. Then, when the blank 81 is placed between exhaust port 18 and sleeve 21, blank area 83 closes off any excess open areas in sleeve 21 and insures a gas-tight seal between sleeve 21 and exhaust port 18.
  • baffle plates 25 and end plate 42 are desirably constructed from steel. It has been found, for example, that the hot exhaust gases emitted from the engine tend to expand sleeve 21. If an identical material, such as aluminum, it used for baffle plates 25, however, the plates also expand and tend to bend or deform in such a manner as to increase the size of the exhaust gas diffusion openings 34 and reduce the noise depressing ability of the muffler. Accordingly, it is desirable in the practice of this invention that the baffle plates 25 and end plates 42 be constructed from a material that is far less expandable when heated than the material used for sleeve 21.
  • the most efficient noise depression can be accomplished when the openings 34 between adjacent baffle plates 25 are maintained in the range of about .005 to .010 inch.
  • the most desirable distance between adjacent baffle plates 25 to accomplish effective gas diffusion without the loud cracking engine sound is about .005 to .010 inch.
  • this spacing can be varied, depending upon the type materials used for baffle plates 25, the relative size of slots 40 and' thequantity-of exhaust gases generated by the particular engine. It is contemplated in the practice of this invention, therefore, that the size of slots 40 and the spacing between baffle plates 25 be adjusted to permit the maximum amount of, exhaust gas diffusion without significant impairment of the noise reducing ability of the muffler.
  • more or less than nine baffle plates 25 can be used for any given engine to increase or decrease the ability of the muffler assembly to quietly diffuse exhaust gases into the atmosphere.
  • a universally adaptable noise depressing device for a combustion engine adaptable for use with differently sized engines having varying engine displacement and exhaust port characteristics comprising:
  • tubular sleeve means secured to said engine and aligned at one end with the exhaust port thereof for defining an extended chamber for receiving exhaust gases emitted from said engine;
  • baffle plates removably secured to the opposite end of said tubular sleeve means which define a plurality of openings through which exhaust gases emitted from said engine are diffused in a stage-wise fashion into the atmosphere, said baffle plates having a plurality of registered openings formed therein to successively transmit said exhaust gases and said plates being successively arranged in a series transversely to said tubular sleeve means;
  • baffle plates for removably securing said baffle plates to said tubular sleeve so that varying numbers of said plates can be arranged in said series; spacing means disposed between adjacent baffle plates to maintain said plates in a spaced relationship with respect to each other and to separate each of said plates a predetermined distance from each succeeding plate; and i an alignment adaptor means disposed between and extending within said tubular sleeve means and said engine exhaust port to maintain said port and said sleeve means in an aligned, sealed relationship.
  • baffle plates are maintained in a spaced position relative to one another and wherein the distance between each adjacent plate is in the range of about .005 to .010 inch.
  • tubular sleeve means is constructed from a material that is relatively more heat expandable than the material from which said baffle plates are constructed.
  • the noise depressing device of claim 1 which is further characterized by including means for securing said tubular sleeve means to said engine.
  • said alignment adaptor means is a cross-shaped key having four oppositely disposed edges, one of said edges fitting within said exhaust port and an opposite of said edges fitting within said tubular sleeve means.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Silencers (AREA)
US00301178A 1972-10-26 1972-10-26 Engine noise depressing assemblies Expired - Lifetime US3779342A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US30117872A 1972-10-26 1972-10-26

Publications (1)

Publication Number Publication Date
US3779342A true US3779342A (en) 1973-12-18

Family

ID=23162285

Family Applications (1)

Application Number Title Priority Date Filing Date
US00301178A Expired - Lifetime US3779342A (en) 1972-10-26 1972-10-26 Engine noise depressing assemblies

Country Status (3)

Country Link
US (1) US3779342A (enExample)
JP (1) JPS4973545A (enExample)
DE (1) DE2352599A1 (enExample)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987867A (en) * 1975-03-26 1976-10-26 Discojet Corporation Spark arresting muffler for engines
DE2539884A1 (de) * 1975-09-08 1977-03-17 Hilti Ag Pulverkraftbetriebenes bolzensetzgeraet mit schalldaempfung
US4090583A (en) * 1976-02-02 1978-05-23 Leonard James L Streamlined monolithic internal combustion engine muffler
US4093110A (en) * 1977-03-11 1978-06-06 Olin Corporation Noise and fouling reducer for powder-actuated tool
US4541506A (en) * 1982-04-21 1985-09-17 Scott Venning Exhaust diffusion apparatus
EP0131350A3 (en) * 1983-03-17 1986-05-28 Chillcotts Limited Exhaust silencer
US5869793A (en) * 1996-12-11 1999-02-09 Supertrapp Industries, Inc. Oval shaped spark arresting muffler for engines
US6467569B2 (en) 2001-01-19 2002-10-22 Supertrapp Industries Spark arresting muffler with exhaust path parallel to muffler centerline

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2923936B2 (ja) * 1994-11-07 1999-07-26 マックス株式会社 空気圧駆動式釘打機の減音装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2954839A (en) * 1958-11-06 1960-10-04 Stephen J Gibel Muffler
US3154174A (en) * 1962-11-30 1964-10-27 Alvin S Haining Dual purpose muffler with valved by-pass means
US3497031A (en) * 1969-02-04 1970-02-24 Dennis M Kedziora Exhaust silencer
US3590945A (en) * 1970-04-03 1971-07-06 Milo E Murphy Tuned resonance mufflers
US3669216A (en) * 1971-07-06 1972-06-13 Donald H Spies Model airplane muffler constructions

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2954839A (en) * 1958-11-06 1960-10-04 Stephen J Gibel Muffler
US3154174A (en) * 1962-11-30 1964-10-27 Alvin S Haining Dual purpose muffler with valved by-pass means
US3497031A (en) * 1969-02-04 1970-02-24 Dennis M Kedziora Exhaust silencer
US3590945A (en) * 1970-04-03 1971-07-06 Milo E Murphy Tuned resonance mufflers
US3669216A (en) * 1971-07-06 1972-06-13 Donald H Spies Model airplane muffler constructions

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987867A (en) * 1975-03-26 1976-10-26 Discojet Corporation Spark arresting muffler for engines
DE2539884A1 (de) * 1975-09-08 1977-03-17 Hilti Ag Pulverkraftbetriebenes bolzensetzgeraet mit schalldaempfung
US4090583A (en) * 1976-02-02 1978-05-23 Leonard James L Streamlined monolithic internal combustion engine muffler
US4093110A (en) * 1977-03-11 1978-06-06 Olin Corporation Noise and fouling reducer for powder-actuated tool
US4541506A (en) * 1982-04-21 1985-09-17 Scott Venning Exhaust diffusion apparatus
EP0131350A3 (en) * 1983-03-17 1986-05-28 Chillcotts Limited Exhaust silencer
US5869793A (en) * 1996-12-11 1999-02-09 Supertrapp Industries, Inc. Oval shaped spark arresting muffler for engines
US6467569B2 (en) 2001-01-19 2002-10-22 Supertrapp Industries Spark arresting muffler with exhaust path parallel to muffler centerline

Also Published As

Publication number Publication date
JPS4973545A (enExample) 1974-07-16
DE2352599A1 (de) 1974-05-09

Similar Documents

Publication Publication Date Title
US3779342A (en) Engine noise depressing assemblies
US3927731A (en) Muffler with spiral duct and double inlets
US2808896A (en) Exhaust mufflers for internal combustion engines
JPS52139820A (en) Exhaust gas purifier for internal combustion engine
DE69205513D1 (de) Steuersystem für das Luft/Kraftstoff-Verhältnis einer Brennkraftmaschine mit variabler Ventilsteuerung.
US20190203619A1 (en) Exhaust system having tunable exhaust sound
GB1099612A (en) Silencer for internal combustion engines
US4671381A (en) Linear muffler shockwave suppressor
US3749199A (en) Exhaust gas muffler for internal combustion engines of vehicles
US3400784A (en) Muffler with tangential exhaust intake and porous ends
US4891003A (en) Pulse combustion device
US3520131A (en) Exhaust gas control
US4305477A (en) Exhaust tuning means for internal combustion engines
US4114373A (en) Internal combustion engine having siamesed exhaust ports and an aftercombustion chamber
US3897854A (en) Exhaust muffler for internal combustion engines
US3688869A (en) Muffler with resilient exterior
GB1157150A (en) Improvements in Noise Suppressors for Jet Engines
US4341284A (en) Silencer means for internal combustion engines
US4090583A (en) Streamlined monolithic internal combustion engine muffler
US3958660A (en) Muffler system
US3810450A (en) Stuffer for two-cycle engines
JPS53342A (en) Exhaust gas cleaner of internal combustion engine
GB2352480A (en) I.c. engine exhaust noise suppressor
US2097279A (en) Backfire trap
GB499368A (en) Improvements in silencers for operation with a plurality of internal combustion engines