US3882961A - Muffler for vacuum-inducing motor - Google Patents
Muffler for vacuum-inducing motor Download PDFInfo
- Publication number
- US3882961A US3882961A US456541A US45654174A US3882961A US 3882961 A US3882961 A US 3882961A US 456541 A US456541 A US 456541A US 45654174 A US45654174 A US 45654174A US 3882961 A US3882961 A US 3882961A
- Authority
- US
- United States
- Prior art keywords
- muffler
- air
- motor
- layer
- inlet
- 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
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Images
Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
- A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
- A47L9/10—Filters; Dust separators; Dust removal; Automatic exchange of filters
- A47L9/12—Dry filters
- A47L9/122—Dry filters flat
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
- A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
- A47L9/0081—Means for exhaust-air diffusion; Means for sound or vibration damping
-
- 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
- F01N1/10—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling in combination with sound-absorbing materials
-
- 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
- Y10S55/00—Gas separation
- Y10S55/03—Vacuum cleaner
Definitions
- the muffler includes an attenuator box and a multi-layer muffler filler.
- the layers of the muffler filler are reticulated polyurethane foam of varying pore densities. Air is directed through the muffler from the least dense to the most dense layer.
- FIGS. 1-4 a preferred embodiment of The present invention relates generally to a muffler, the pre invention Shown as a muffler, g r lly and more particularly to an air-filtering, soundattenuating muffler for use on a vacuum cleaning machine.
- Such machines operate by means of a vacuuminducing motor. In many cases, this motor produces a highly objectionable shrill noise which is heard through the exhaust port of the motor.
- the exhaust air is, for practical purposes, clean, it may contain dust and dirt particulate matter. In a sterile environment, such as a hospital, it is highly desirable that this very fine matter be filtered out of the air flow.
- the flow of air through the exhaust port is direct and strong, and the force of the flow can adversely effect the sound attenuation capability of the muffler.
- the exhaust air flow can also result in substantial air turbulence, such that dust and dirt particles in the vicinity of the cleaning machine become unsettled and airborne. This substantially reduces the effectiveness of the vacuum cleaning machine.
- the present invention comprises an attenuator box which contains a muffler filler.
- the filler consists of a series of reticulated foam layers of varying pore densities (as defined below) which are arranged in order of increasing pore density.
- the flow of air from the vacuum motor, and thus the motor noise and dirt particles, is directed from an inlet of the attenuator box into the least dense filler layer. The air then passes and diffuses through the remaining denser layers and exits the muffler assembly through an outlet port.
- FIG. 3 is an enlarged top view of the attenuator box shown in FIG. 2;
- FIG. 4 is an enlarged cross sectional view of the preferred embodiment shown in FIG. 1 taken along 4-4.
- the muffler includes two basic components, i.e., an attenuator box 4 and a muffler tiller 6.
- the attenuator box 4 is rectangular and includes a substantially vertical partition 8 which divides the attenuator box 4, thereby defining an intake portion 10 and a muffler portion 12.
- a pair of substantially horizontal wall members l4, 16 are secured within the intake portion 10 to define an intake v chamber 18.
- the intake chamber 18 is connected to the vacuum-inducing motor of a vacuum cleaning machine (not shown) through an inlet port 20 in the upper wall member 14.
- the intake chamber 18 is a significant feature of the present invention because it effectively and substantially disrupts the forceful flow of air from the vacuum motor. As this air passes through the inlet 20, it impinges upon the lower wall member 16, and thus, the uniform flow pattern is substantially destroyed. The air then continuously and randomly circulates within the intake chamber 18.
- the wall members 14, 16 are recessed from the top and bottom surfaces 22, 24 of the attenuator box 4. This facilitates attachment of the muffler 2 to the vacuum cleaning machine.
- the muffler portion 12 is adapted to receive the muffler tiller 6.
- the muffler portion 12 defines a cavity, generally designated 26, which directly communicates with the intake chamber 18 through a substantially horizontal slot 28 in the partition 8.
- the muffler portion 12 also defines a pair of outlet ports 30, 32 in the top and bottom surfaces 22, 24, respectively, of the attenuator box 4.
- a pair of flanges 34, 36 extend peripherally about the outlet ports 30, 32, respectively. The flanges 34, 36 assist in maintaining the muffler filler 6 within the cavity 26.
- the muffler tiller 6, shown in cross-section in FIG. 4, is a composite structure including a series of reticulated foam layers, generally designated 38.
- the layers 38 are 'open cell polyurethane foam of varying pore density.
- pore density is defined as pores per linear inch.
- Such foam is presently available under the trade name Scotts Industrial Foam.
- the center layer 40 of the muffler tiller 6 is the least dense layer and the layers 42-56 are arranged in order of increasing pore density about the center layer 40. That is, the pore density of the layers 38 increases from the center layer 40 to the exterior layers 54, 56.
- the preferred pore densities are given in the following table.
- center layer 40 is twice as thick as the other layers 42-56. This is the result of the process used in fabricating the muffler tiller 6. From 3 stock material, sheets of 10, 25, 65, 80 and 100 PPI are cut to appropriate dimensions and secured together by appropriate means, such as gluing or sewing. This block of material is then folded upon itself and the interface between the two layers of 10 PPI is glued or sewn to produce the muffler filler 6, as shown.
- the flow of air from the vacuum motor shown in FIG. 4 by an arrow 58, enters the intake chamber 18 through the inlet port 20.
- the flow 58 is substantially interrupted, as indicated above, and the air is directed through the slot 28 into the muffler portion 12 of the attenuator box 4.
- the slot 28 substantially aligns with the center layer 40 of the muffler filler 6, and thus, the air passes directly into the center layer 40. The air then diffuses vertically upwards and downwards through the remaining, more dense layers 4256 and exits the muffler 2 through the outlets 30, 32.
- the muffler 2 includes air control means, generally designated 60, for directing the flow of air 58 directly into the center and least dense layer 40 of the muffler filler 6,.and then through the remaining, increasingly dense layers 42-56.
- the muffler filler 6 of varying pore density reticulated foam layers 38 provides substantial sound attentuation, without substantial reflection or back pressure problems.
- the center layer 40 being of lowest pore density, presents only limited resistance to the flow of air through the slot 28, and the graduation of densities 30 about the center layer 40 permitsthe air to readily diffuse through the muffler filler 6. This substantially avoids the problem of air reflection back towards and through the slot 28.
- the sound absorbing capability of the layers 38 incrementally increases from the center layer 40 to the exterior layers 54, 56.
- Each layer 42-56 also presents additional interference and resistance to the air flow 58, such that the flow of air through the outlet ports 30,
- the attenuator box 2 need not be box-shaped, and use of the term box should not be construed in the sense of a limitation.
- An airfiltering, sound-attenuating muffler for a vacuum-inducing motor comprising, in combination:
- an attenuator box having an inlet and an outlet, said inlet being in direct communication with said
- said attenuator box for receiving a flow of air from said motor, said attenuator box defining a muffler cavity;
- a muffler filler within said muffler cavity, said muffler filler including a series of reticulated foam layers of varying pore densities, said layers being arranged in order of increasing pore density, a first layer having I the lowest pore density; and
- air control means for directing said flow of air from said inlet into said first layer of said muffler material and through said series of layers and said outlet, whereby the noise produced by said motor and carried by said air is substantially absorbed and attenuated by said muffler.
- An air-filtering, sound-attenuating muffler for vacuum-inducing motor comprising, in combination:
- an attenuator box having inlet means and outlet means, said inlet means receiving a flow of air from said motor, said attenuator defining a muffler cava muffler filler within said muffler cavity, said muffler filler including a series of reticulated foam layers of varying pore densities, a central layer having the lowest pore density, a first outer layer and a second outer layer having the highest pore density, said first and second outer layers being in direct communication with said outlet means, said layers being arranged about said central layer in order of increasing pore densities; and
- air control means for directing said flow of air from said inlet into said central layer, whereby said air passes through said muffler filler in two directions and exists said attenuator box through said outlet means.
- a muffler for a vacuum-inducing motor comprising, in combination:
- an attenuator box having an inlet, said inlet being in direct communication with said motor for receiving a flow of air from said motor, said attenuator box defining a muffler cavity;
- a muffler filler with said muffler cavity, said filler including a series of foam layers of varying pore densities, a first layer having the lowest pore density and a second layer having the greatest poredensity;
- air control means for directing said flow of air from said inlet into and through said muffler filler from said first layer to said second layer, whereby the noise produced by said motor and carried by said air is substantially absorbed and attenuated by said muffler.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Exhaust Silencers (AREA)
Abstract
Description
Claims (11)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US456541A US3882961A (en) | 1974-04-01 | 1974-04-01 | Muffler for vacuum-inducing motor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US456541A US3882961A (en) | 1974-04-01 | 1974-04-01 | Muffler for vacuum-inducing motor |
Publications (1)
Publication Number | Publication Date |
---|---|
US3882961A true US3882961A (en) | 1975-05-13 |
Family
ID=23813172
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US456541A Expired - Lifetime US3882961A (en) | 1974-04-01 | 1974-04-01 | Muffler for vacuum-inducing motor |
Country Status (1)
Country | Link |
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US (1) | US3882961A (en) |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2307959A1 (en) * | 1975-04-16 | 1976-11-12 | Freudenberg Carl | SILENCER FOR AIR EXHAUST PORTS OF COMPRESSED AIR EQUIPMENT |
US4137647A (en) * | 1977-09-06 | 1979-02-06 | Clark Jr James N | Heat and humidity recovery device for use with clothes dryer |
US4207883A (en) * | 1978-07-14 | 1980-06-17 | Nuclear & Environmental Protection, Inc. | Hood assembly with noise filter |
US4302224A (en) * | 1979-10-12 | 1981-11-24 | Greene & Kellogg, Inc. | Compact oxygen concentrator |
US4342573A (en) * | 1979-10-12 | 1982-08-03 | Greene & Kellogg, Incorporated | Compact oxygen concentrator |
US4519112A (en) * | 1983-11-07 | 1985-05-28 | The National Super Service Company | Muffled vacuum cleaner |
US4565259A (en) * | 1983-07-26 | 1986-01-21 | Kurt Stoll | Connection block |
US4631077A (en) * | 1985-03-26 | 1986-12-23 | Pipercrosslimited | Foam plastic air filter |
US4704143A (en) * | 1985-11-20 | 1987-11-03 | Percy Donald W | Multistage micronic in-line after-air filter |
US4915245A (en) * | 1988-05-12 | 1990-04-10 | General Dynamics Corp., Pomona Div. | Electrostatic-safe, air-powered, miniature vacuum generator |
US5067584A (en) * | 1990-04-25 | 1991-11-26 | Williams William H | Low cost replaceable type sound dampening unit for vacuum cleaning machine |
US5737797A (en) * | 1995-11-28 | 1998-04-14 | Iowa State University Research Foundation, Inc. | Central vacuum with acoustical damping |
US6052863A (en) * | 1995-10-20 | 2000-04-25 | Iowa State University Research Foundation, Inc. | Central vacuum cleaner muffler |
EP1510166A2 (en) * | 2003-08-26 | 2005-03-02 | Suzhou Kingclean Floorcare Co., Ltd. | Silencer for vacuum cleaner |
EP1510165A3 (en) * | 2003-08-26 | 2005-11-09 | Suzhou Kingclean Floorcare Co., Ltd. | Silencer for vacuum cleaner |
US20060150360A1 (en) * | 2005-01-10 | 2006-07-13 | Christian Reick-Mitrisin | Vacuum system and method |
US20060179601A1 (en) * | 2005-02-17 | 2006-08-17 | Shop Vac Corporation | Removable internal air diffuser |
AT501671B1 (en) * | 2002-12-12 | 2007-01-15 | Suzhou Kingclean Floorcare Co | MUFFLER FOR USE IN A VACUUM CLEANER |
US20080016646A1 (en) * | 2005-01-10 | 2008-01-24 | Martin Gagnon | Housing assembly for a vacuum |
WO2008009602A1 (en) * | 2006-07-21 | 2008-01-24 | Basf Se | Use of modified open-cell foam materials in vacuum cleaners |
EP2510850A1 (en) | 2011-04-12 | 2012-10-17 | BSH Bosch und Siemens Hausgeräte GmbH | Low-noise waste air filter assembly |
DE102014103992A1 (en) * | 2014-03-24 | 2015-09-24 | Miele & Cie. Kg | Filter arrangement for a vacuum cleaner |
EP3517011A1 (en) * | 2018-01-25 | 2019-07-31 | BSH Hausgeräte GmbH | Filter assembly for reducing noise for a vacuum cleaner |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2586935A (en) * | 1948-03-26 | 1952-02-26 | Fram Corp | Gas filter |
US2907405A (en) * | 1957-11-25 | 1959-10-06 | American Felt Co | Filter-silencer |
US3009531A (en) * | 1958-08-01 | 1961-11-21 | Theodore E Mead | Muffler |
US3102014A (en) * | 1961-05-03 | 1963-08-27 | Electro Air Cleaner Company In | Air filter curtain |
US3144315A (en) * | 1962-08-17 | 1964-08-11 | John L Hunn | Air filter for internal combustion engines |
US3308608A (en) * | 1960-01-28 | 1967-03-14 | Electrolux Ab | Vacuum cleaner |
US3344588A (en) * | 1967-10-03 | Vacuum cleaner | ||
US3466696A (en) * | 1966-07-22 | 1969-09-16 | Electrolux Ab | Vacuum cleaner |
-
1974
- 1974-04-01 US US456541A patent/US3882961A/en not_active Expired - Lifetime
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3344588A (en) * | 1967-10-03 | Vacuum cleaner | ||
US2586935A (en) * | 1948-03-26 | 1952-02-26 | Fram Corp | Gas filter |
US2907405A (en) * | 1957-11-25 | 1959-10-06 | American Felt Co | Filter-silencer |
US3009531A (en) * | 1958-08-01 | 1961-11-21 | Theodore E Mead | Muffler |
US3308608A (en) * | 1960-01-28 | 1967-03-14 | Electrolux Ab | Vacuum cleaner |
US3102014A (en) * | 1961-05-03 | 1963-08-27 | Electro Air Cleaner Company In | Air filter curtain |
US3144315A (en) * | 1962-08-17 | 1964-08-11 | John L Hunn | Air filter for internal combustion engines |
US3466696A (en) * | 1966-07-22 | 1969-09-16 | Electrolux Ab | Vacuum cleaner |
Cited By (32)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4082160A (en) * | 1975-04-16 | 1978-04-04 | Firma Carl Freudenberg | Silencer for exhausting gas streams |
FR2307959A1 (en) * | 1975-04-16 | 1976-11-12 | Freudenberg Carl | SILENCER FOR AIR EXHAUST PORTS OF COMPRESSED AIR EQUIPMENT |
US4137647A (en) * | 1977-09-06 | 1979-02-06 | Clark Jr James N | Heat and humidity recovery device for use with clothes dryer |
US4207883A (en) * | 1978-07-14 | 1980-06-17 | Nuclear & Environmental Protection, Inc. | Hood assembly with noise filter |
US4302224A (en) * | 1979-10-12 | 1981-11-24 | Greene & Kellogg, Inc. | Compact oxygen concentrator |
US4342573A (en) * | 1979-10-12 | 1982-08-03 | Greene & Kellogg, Incorporated | Compact oxygen concentrator |
US4565259A (en) * | 1983-07-26 | 1986-01-21 | Kurt Stoll | Connection block |
US4519112A (en) * | 1983-11-07 | 1985-05-28 | The National Super Service Company | Muffled vacuum cleaner |
US4631077A (en) * | 1985-03-26 | 1986-12-23 | Pipercrosslimited | Foam plastic air filter |
US4704143A (en) * | 1985-11-20 | 1987-11-03 | Percy Donald W | Multistage micronic in-line after-air filter |
US4915245A (en) * | 1988-05-12 | 1990-04-10 | General Dynamics Corp., Pomona Div. | Electrostatic-safe, air-powered, miniature vacuum generator |
US5067584A (en) * | 1990-04-25 | 1991-11-26 | Williams William H | Low cost replaceable type sound dampening unit for vacuum cleaning machine |
US6052863A (en) * | 1995-10-20 | 2000-04-25 | Iowa State University Research Foundation, Inc. | Central vacuum cleaner muffler |
US5737797A (en) * | 1995-11-28 | 1998-04-14 | Iowa State University Research Foundation, Inc. | Central vacuum with acoustical damping |
AT501671B1 (en) * | 2002-12-12 | 2007-01-15 | Suzhou Kingclean Floorcare Co | MUFFLER FOR USE IN A VACUUM CLEANER |
EP1510165A3 (en) * | 2003-08-26 | 2005-11-09 | Suzhou Kingclean Floorcare Co., Ltd. | Silencer for vacuum cleaner |
EP1510166A3 (en) * | 2003-08-26 | 2005-11-09 | Suzhou Kingclean Floorcare Co., Ltd. | Silencer for vacuum cleaner |
US20050044654A1 (en) * | 2003-08-26 | 2005-03-03 | Zugen Ni | Silencer for vacuum cleaner |
EP1510166A2 (en) * | 2003-08-26 | 2005-03-02 | Suzhou Kingclean Floorcare Co., Ltd. | Silencer for vacuum cleaner |
US7461430B2 (en) | 2005-01-10 | 2008-12-09 | Broan-Nutone Llc | Vacuum system and method |
US20060150360A1 (en) * | 2005-01-10 | 2006-07-13 | Christian Reick-Mitrisin | Vacuum system and method |
US20080016646A1 (en) * | 2005-01-10 | 2008-01-24 | Martin Gagnon | Housing assembly for a vacuum |
US7627928B2 (en) * | 2005-02-17 | 2009-12-08 | Shop-Vac Corporation | Removable internal air diffuser |
US20060179601A1 (en) * | 2005-02-17 | 2006-08-17 | Shop Vac Corporation | Removable internal air diffuser |
US20100071151A1 (en) * | 2005-02-17 | 2010-03-25 | Shop Vac Corporation | Removable Internal Air Diffuser |
US9107549B2 (en) * | 2005-02-17 | 2015-08-18 | Shop Vac Corporation | Removable internal air diffuser |
WO2008009602A1 (en) * | 2006-07-21 | 2008-01-24 | Basf Se | Use of modified open-cell foam materials in vacuum cleaners |
US20100294313A1 (en) * | 2006-07-21 | 2010-11-25 | Basf Se | Use of modified open-cell foam materials in vacuum cleaners |
EP2510850A1 (en) | 2011-04-12 | 2012-10-17 | BSH Bosch und Siemens Hausgeräte GmbH | Low-noise waste air filter assembly |
DE102011007210A1 (en) * | 2011-04-12 | 2012-10-18 | BSH Bosch und Siemens Hausgeräte GmbH | Low-noise exhaust air filter arrangement |
DE102014103992A1 (en) * | 2014-03-24 | 2015-09-24 | Miele & Cie. Kg | Filter arrangement for a vacuum cleaner |
EP3517011A1 (en) * | 2018-01-25 | 2019-07-31 | BSH Hausgeräte GmbH | Filter assembly for reducing noise for a vacuum cleaner |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SERVICEMASTER INVESTMENT COMPANY, CORPORATE TRUST Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SERVICEMASTER INDUSTRIES INC., A CORP. OF DE.;REEL/FRAME:004666/0908 Effective date: 19860101 Owner name: SERVICEMASTER INVESTMENT COMPANY, CORPORATE TRUST Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SERVICEMASTER INDUSTRIES INC., A CORP. OF DE.;REEL/FRAME:004666/0908 Effective date: 19860101 |
|
AS | Assignment |
Owner name: SERVICEMASTER COMPANY L.P., THE, 2300 WARRENVILLE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SERVICEMASTER INVESTMENT COMPANY, A DE. CORP.;REEL/FRAME:004667/0004 Effective date: 19861230 Owner name: SERVICEMASTER COMPANY L.P., THE, A DE. LIMITED PAR Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SERVICEMASTER INVESTMENT COMPANY, A DE. CORP.;REEL/FRAME:004667/0004 Effective date: 19861230 |