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US4161996A Expired / Lapsed US ⏱️ 0.0 years remaining

Exhaust muffler

Assignee: Atlas Copco AB
•
Filing: 1978-01-23
•
Granted: 1979-07-24
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Expires: 1998-01-23
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Abstract

Abstract An exhaust muffler intended for noise dampening of, for instance, pneumatic tools, comprising a variable flow restricting passage, an attenuation chamber and a non-variable flow restricting passage. A valve body is arranged to control said variable flow restricting passage in response to the actual exhaust gas pressure. A movement dampening chamber, partly defined by the valve body, communicates with the atmosphere through a restriction opening to prevent resonance vibration of the valve body.

Inventors

  • 👤 Miroslav Dolejsi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 14:50
CPC Classifications
F; F01; F01N; F01N1/00; F01N1/16; F01N1/165; F16; F16K; F16K15/00; F16K15/02; F16K15/025; F16K17/00; F16K17/02; F16K17/04; F16K17/0433; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/785; Y10T137/7851; Y10T137/7859; Y10T137/7904; Y10T137/7922; Y10T137/7925

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 144 words
An exhaust muffler for pressure gas driven motors, comprising: exhaust gas receiving means adapted to be coupled to an exhaust outlet of a pressure gas driven motor; a variable flow restricting passage (14) coupled to said exhaust gas receiving means; a spring biased valve body (12) in communication with said exhaust gas receiving means and with said variable flow restricting passage (14) and responsive to the actual exhaust gas pressure to maintain a constant pressure drop across the exhaust muffler by continuously adapting the area of said variable flow restricting passage (14) to the actual exhaust pressure; and a vibration dampening means (21,22) associated with said valve body (12) for preventing resonance oscillation of said valve body, said vibration dampening means comprising a chamber (21) partly defined by said valve body (12); and a restriction opening (22) connecting said chamber (21) to the atmosphere.
Claim 2
Dependent Claim 144 words
An exhaust muffler for pressure gas driven motors, comprising: exhaust gas receiving means adapted to be coupled to an exhaust outlet of a pressure gas driven motor; a variable flow restricting passage (14) coupled to said exhaust gas receiving means; a spring biased valve body (12) in communication with said exhaust gas receiving means and with said variable flow restricting passage (14) and responsive to the actual exhaust gas pressure to maintain a constant pressure drop across the exhaust muffler by continuously adapting the area of said variable flow restricting passage (14) to the actual exhaust pressure; and a vibration dampening means (21,22) associated with said valve body (12) for preventing resonance oscillation of said valve body, said vibration dampening means comprising a chamber (21) partly defined by said valve body (12); and a restriction opening (22) connecting said chamber (21) to the atmosphere.
Claim 3
Dependent Claim 29 words
Exhaust muffler according to claim 1, wherein said restriction opening (22) is formed in said exhaust gas receiving means, said exhaust gas receiving means partly defining said chamber (21).
Claim 4
Dependent Claim 90 words
Exhaust muffler according to claim 1, wherein said exhaust gas receiving means comprises a cylinder (10) communicating with the exhaust outlet of the motor; and wherein said variable flow restricting passage comprises a plurality of radial openings (14) extending through the wall of said cylinder (10), said valve body (12) being axially movable within said cylinder (10) to selectively open or block said radial openings responsive to said exhaust gas pressure to control the joint or total area of said radial openings in response to the actual exhaust gas pressure.
Claim 5
Dependent Claim 17 words
Exhaust muffler according to claim 3, wherein said cylinder (10) at least partly defines said chamber (21).
Claim 6
Dependent Claim 23 words
Exhaust muffler according to claim 4, wherein said cylinder (10) has an end wall (16) which at least partly defines said chamber (21).
Claim 7
Dependent Claim 18 words
Exhaust muffler according to claim 5, wherein said restriction opening (22) is formed in said end wall (16).
Claim 8
Dependent Claim 21 words
Exhaust muffler according to claim 3, wherein said radial openings (14) are distributed in a helical pattern on said cylinder (10).
Claim 9
Dependent Claim 76 words
Exhaust muffler according to claim 3, comprising a compression spring (17) for biasing said valve body (12), and wherein said cylinder (10) has an end wall (16) which forms a reaction support for said compression spring (17) by means of which said valve body (12) is balanced against the exhaust gas pressure, and said end wall (16) having a depressed portion (23) extending into said cylinder (10) to reduce the volume of said dampening chamber (21).
Claim 10
Dependent Claim 21 words
Exhaust muffler according to claim 8, wherein said radial openings (14) are distributed in a helical pattern on said cylinder (10).
Claim 11
Dependent Claim 18 words
Exhaust muffler according to claim 8, wherein said restriction opening (22) is located in said depressed portion (23).
Claim 12
Dependent Claim 61 words
Exhaust muffler according to claim 3, comprising a housing (11) surrounding at least a portion of said cylinder (10), said housing (11) being provided with one or more vent openings forming a non-variable flow restricting passage (32) in gas communication with said variable flow restricting passage (14), an attenuation chamber (30) being formed between said housing (11) and said cylinder (10).
Claim 13
Dependent Claim 21 words
Exhaust muffler according to claim 11 wherein said housing (11) completely surrounds at least a lengthwise portion of said cylinder (10).
Claim 14
Dependent Claim 17 words
Exhaust muffler according to claim 11, wherein said end wall (16) and housing (11) are integrally formed.
Claim 15
Dependent Claim 23 words
Exhaust muffler according to claim 3, wherein said cylinder (10) has an end wall (16) which at least partly defines said chamber (21).
Claim 16
Dependent Claim 17 words
Exhaust muffler according to claim 14, wherein said end wall (16) and housing (11) are integrally formed.
Claim 17
Dependent Claim 90 words
Exhaust muffler according to claim 1, wherein said exhaust gas receiving means comprises a cylinder (10) communicating with the exhaust outlet of the motor; and wherein said variable flow restricting passage comprises a plurality of radial openings (14) extending through the wall of said cylinder (10), said valve body (12) being axially movable within said cylinder (10) to selectively open or block said radial openings responsive to said exhaust gas pressure to control the joint or total area of said radial openings in response to the actual exhaust gas pressure.

References Cited (Backward Citations)

US541609A Cited
US585084A Cited
US1013483A Cited
US1807512A Cited
GB364015A Cited
GB425775A Cited
GB916836A Cited
US3219144A Cited
FR1372464A Cited
GB1192627A Cited
GB1322236A Cited
SE385230B Cited
US3722854A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-07-23 1983-01-22 1983-07-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-07-23 1987-01-22 1987-07-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-07-23 1991-01-22 1991-07-24 $7700.00 Window Closed / Lapsed

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