US3690404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective frequency stethoscope structure
Assignee: BIO DATA Inc
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Filing: 1971-07-30
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Granted: 1972-09-12
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Expires: 1991-07-30
Abstract
Abstract A selective frequency range stethoscope consisting of a housing embodying a sound producing chamber, a sound conducting chamber or channel and a rotatable backing plate having passages both formed therein and operatively associated therewith for the selective passage of a frequency range of sound between said chambers. One of said passages is particularly adapted to pass a predominantly low frequency range of sound, one of said passages is adapted to pass a predominantly high frequency range of sound and one of said passages is adapted to pass a full range of sound.
Inventors
- 👤 Ronald J Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:35
CPC Classifications
A; A61; A61B; A61B7/00; A61B7/02; A61B7/026
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
388 words
A stethoscope structure having in combination a housing, a chamber within said housing comprising a sound producing chamber and having one side thereof open to the atmosphere, a second chamber within said housing having an outlet to the atmosphere, a tubular member comprising hearing means being connected to said outlet, a first passage running outwardly from said first chamber, a second passage running outwardly from said second chamber, a plate member movably carried by said housing and having the underside thereof overlying said first and second passages, said plate member having channels formed in said underside thereof adapted upon alignment by movement of said plate member to provide communication between said first and second passages, one of said channels having a cross sectional area of such extent as that of said tubular member that the same full frequency range of the sound produced in said first chamber that would pass through said tubular member is transmitted to said second passage, a second of said channels having a cross sectional area equal to that of said first mentioned channel and having intermediate the ends thereof a tubular aperture to the atmosphere, said aperture being arranged as to cross sectional area and length as to shunt off to the atmosphere the low frequency range portion of the sound generated in said first chamber and to pass to said second chamber the high frequency range portion of said sound, a tubular member running from said first to said second chamber forming a third channel, said third channel having a cross sectional area on the order of one half of the cross sectional area of said first mentioned channel, said cross sectional area being such that with respect to the length thereof, the inertance of the air mass therein attenuates the high frequency portion of the range of sound produced in said first chamber and passes to said second chamber the low frequency portion thereof, and said cross sectional area of said third channel with respect to the length thereof, thE inertance of the air mass therein provides such impedance to passage of sound therethrough relative to that of said first and second channels that said third channel becomes inoperative at such times as either said first or second channels are aligned to connect said passages of said first and second chambers.
Claim 2
Dependent Claim
23 words
The structure set forth in claim 1, including a diaphragm seated onto said housing and overlying said open side of said first chamber.
Claim 3
Dependent Claim
28 words
The structure set forth in claim 1, wherein said plate member has a pair of radial channels formed in the underside thereof and means rotatively secure said plate.
Claim 4
Dependent Claim
59 words
The structure set forth in claim 1, wherein said aperture of said second mentioned channel forms a tubular passage and has a cross sectional area such that the air mass therein presents less impedance to the passage of a low frequency range portion of sound therethrough than presented by the impedance of the air mass within said second channel.
Claim 5
Dependent Claim
70 words
The structure set forth in claim 1, wherein said tubular member forming said third channel has a cross sectional area on the order of one half of the cross sectional area of the bore of said tubular member and a correspondingly determined length such that there is such impedance therein that with communication open between said first and second chambers, sound produced in said first chamber bypasses said tubular member.
References Cited (Backward Citations)
US2632521A
Cited
US2389868A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-12 | 1976-03-13 | 1976-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-12 | 1980-03-13 | 1980-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-12 | 1984-03-13 | 1984-09-12 | $7700.00 | Window Closed / Lapsed |