US3880245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust noise attenuating system with muffler for pneumatic tools
Assignee: Chicago Pneumatic Tool Co LLC
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Filing: 1973-11-21
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Granted: 1975-04-29
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Expires: 1993-11-21
Abstract
Abstract A pneumatic tool having incorporated therein a system including an arrangement of passages together with an expansion chamber, a sound resonator chamber, and a plug type screen muffler having internal screens, whereby this system the usual noise accompanying spent air exhausted from the rotor chamber of an air driven blade rotor in the tool is caused to exhaust to atmosphere relatively quietly, without undesirable pulsing, substantially free of undesirable frequencies and at an acceptable decibel level.
Inventors
- 👤 Jr Carl G Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:12
CPC Classifications
B; B23; B23B; B23B45/00; B23B45/04; Y; Y10; Y10S; Y10S173/00; Y10S173/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
201 words
A pneumatic tool including an air driven motor comprising a rotor liner defining a rotor chamber having an air driven multiple blade rotor operating therein and having exhaust ports through the liner for the exhaust of driving air from the chamber; a housing for the tool encasing the motor having an end cap at its rear end and having a pistolgrip handle depending from its underside adapted to be held by the operator for maneuvering the tool; and a sound attenuating system through which the exhaust air passes to atmosphere comprising an annular channel around the liner into which the exhaust ports open radially, an elongated exhaust passage extending lengthwise through the handle, an exhaust air expansion chamber connecting the annular channel with an upper end of the passage that extends through the handle, a sound resonating cavity located in the cap at one side of and in parallel relation to the annular channel, a partition wall separating the annular channel from the cavity having a group of laterally extending throat ports communicating the annular channel with the cavity, and a sound muffling plug having a threaded connection with a terminal end of the exhaust passage that extends through the handle.
Claim 2
Dependent Claim
201 words
A pneumatic tool including an air driven motor comprising a rotor liner defining a rotor chamber having an air driven multiple blade rotor operating therein and having exhaust ports through the liner for the exhaust of driving air from the chamber; a housing for the tool encasing the motor having an end cap at its rear end and having a pistolgrip handle depending from its underside adapted to be held by the operator for maneuvering the tool; and a sound attenuating system through which the exhaust air passes to atmosphere comprising an annular channel around the liner into which the exhaust ports open radially, an elongated exhaust passage extending lengthwise through the handle, an exhaust air expansion chamber connecting the annular channel with an upper end of the passage that extends through the handle, a sound resonating cavity located in the cap at one side of and in parallel relation to the annular channel, a partition wall separating the annular channel from the cavity having a group of laterally extending throat ports communicating the annular channel with the cavity, and a sound muffling plug having a threaded connection with a terminal end of the exhaust passage that extends through the handle.
Claim 3
Dependent Claim
48 words
A pneumatic tool as in claim 1, wherein the sound resonating cavity is of arcuate form extending for substantially 180* relative to the annular channel and is divided into multiple interconnected sub-chambers each communicating by means of a separate one of the throat ports with the annular channel.
Claim 4
Dependent Claim
61 words
A pneumatic tool as in claim 2, wherein the sub-chambers comprise a central sub-chamber, a pair of end chambers of smaller circumferential extent than the central chamber, a neck passage connecting the central chamber at one end with one of the end chambers, and a second neck passage connecting the central chamber at its other end with the other end chamber.
Claim 5
Dependent Claim
150 words
In a pneumatic tool as in claim 1, wherein the sound muffling plug comprises a hollow open ended bushing body having a cylindrical interior and a threaded external section engaged with a complementary threaded terminal end of the exhaust passage that extends through the handle, a group of circular flat screens fitted across the interior of the bushing and fixed therein in parallel spaced relation to each other and all confined wholly within the interior of the bushing, a first screen of the group being located adjacent an inner open end of the bushing , a second screen of the group being located adjacent an opposite open outer end of the bushing, a third final screen of the group being located between the first and second screens but closer to the second screen, and a soft metal sleeve being disposed in abutting end relation between the second and third screens.
Claim 6
Dependent Claim
152 words
For use in combination with the exhaust outlet of a pneumatically driven air vane motor, a muffling plug for attenuating the sound of exhaust air escaping from the outlet to atmosphere comprising a hollow open ended bushing body having a cylindrical interior and a threaded external section adapted to be threadedly connected in the outlet, and a group of circular flat screens fitted across the interior of the bushing and fixed therein in parallel spaced relation to each other, in which a first screen of the group is located adjacent an inner open end of the bushing, a second screen of the group is located adjacent an opposite open outer end of the bushing, a third final screen of the group is located between the first and second screens but closer to the second screen, and a soft metal sleeve is disposed in abutting end relation between the second and third screens.
Claim 7
Dependent Claim
152 words
For use in combination with the exhaust outlet of a pneumatically driven air vane motor, a muffling plug for attenuating the sound of exhaust air escaping from the outlet to atmosphere comprising a hollow open ended bushing body having a cylindrical interior and a threaded external section adapted to be threadedly connected in the outlet, and a group of circular flat screens fitted across the interior of the bushing and fixed therein in parallel spaced relation to each other, in which a first screen of the group is located adjacent an inner open end of the bushing, a second screen of the group is located adjacent an opposite open outer end of the bushing, a third final screen of the group is located between the first and second screens but closer to the second screen, and a soft metal sleeve is disposed in abutting end relation between the second and third screens.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |