GB1205569A - Improvements in or relating to stethoscopes - Google Patents
Improvements in or relating to stethoscopesInfo
- Publication number
- GB1205569A GB1205569A GB50427/66A GB5042766A GB1205569A GB 1205569 A GB1205569 A GB 1205569A GB 50427/66 A GB50427/66 A GB 50427/66A GB 5042766 A GB5042766 A GB 5042766A GB 1205569 A GB1205569 A GB 1205569A
- Authority
- GB
- United Kingdom
- Prior art keywords
- output
- frequency
- input
- oscillator
- transducer
- 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
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B7/00—Instruments for auscultation
- A61B7/02—Stethoscopes
- A61B7/04—Electric stethoscopes
Landscapes
- Acoustics & Sound (AREA)
- Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Medical Informatics (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Signal Processing (AREA)
- Molecular Biology (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Ultra Sonic Daignosis Equipment (AREA)
- Measuring And Recording Apparatus For Diagnosis (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
1,205,569. Stethoscopic amplifier. E.M.I. ELECTRONICS (CANADA) Ltd. 12 Oct., 1967 [10 Nov., 1966], No. 50427/66. Headings H4J and H4R. In a stethoscope having an input transducer 1 (Fig. 1), an output transducer 8<SP>1</SP> and two oscillators 3, 4, the oscillations generated by the first oscillator 3 are frequency modulated by the electrical signals from the input transducer 1. The second oscillator 4 generates oscillations at the (unmodulated) frequency of the first oscillator 3. The outputs from both oscillators are passed through a mixer 5 and a filter 6 which selects signals at the difference frequency. Such difference frequency signals are applied to an output transducer 6 to provide an output acoustic wave pattern related to the input acoustic wave pattern but translated in frequency thereto so as to lie in a more easily audible frequency region. In operation and in the absence of an incident wave pattern, there is substantially no audible acoustic output wave pattern. Alternatively, a suppressed carrier amplitude modulator 10 (Fig. 3) modulates the amplitude of the oscillations generated by a first oscillator 9. A mixer 5 mixes the outputs from the modulator 10 and from a second oscillator 4 which generates oscillations at a reference frequency. The difference frequency is selected by a filter 6. The output transducer 8<SP>1</SP> provides an output pattern related to the input pattern but translated in frequency so as to lie in a more easily audible frequency region. In operation and in the absence of an incident wave there is substantially no audible acoustic wave pattern. The input transducer may be of ceramic type. An output point 7 permits direct monitoring of the input signal. A transistorized circuit of the stethoscope of Fig. 1 is given in which the oscillators 3, 4 comprise astable multivibrators (Fig. 2, not shown). There may be selective input and/or output filtering to discriminate different types of signal, amplitude compression to emphasize low level signals, and automatic gain control to compensate for signal variation from one patient to another. The output signal may be recorded on disc or magnetic tape for reference.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB50427/66A GB1205569A (en) | 1966-10-10 | 1966-10-10 | Improvements in or relating to stethoscopes |
US652892A US3562428A (en) | 1966-10-10 | 1967-07-12 | Arrangements for use in the examination of sound wave patterns |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB50427/66A GB1205569A (en) | 1966-10-10 | 1966-10-10 | Improvements in or relating to stethoscopes |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1205569A true GB1205569A (en) | 1970-09-16 |
Family
ID=10455858
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB50427/66A Expired GB1205569A (en) | 1966-10-10 | 1966-10-10 | Improvements in or relating to stethoscopes |
Country Status (2)
Country | Link |
---|---|
US (1) | US3562428A (en) |
GB (1) | GB1205569A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0228178A2 (en) * | 1985-12-27 | 1987-07-08 | TDK Corporation | Displacement sensor |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3895316A (en) * | 1973-08-29 | 1975-07-15 | W P Instr Inc | Complex tone modulation |
US4220160A (en) * | 1978-07-05 | 1980-09-02 | Clinical Systems Associates, Inc. | Method and apparatus for discrimination and detection of heart sounds |
TW589527B (en) * | 2002-09-20 | 2004-06-01 | Realtek Semiconductor Corp | Device and method for automatically recognizing output and input of analog signal |
SE528409C2 (en) * | 2005-02-21 | 2006-11-07 | Computerized Medical Technolog | Electronic sound monitor for use as stethoscope, has vibration transducer adapted to transform vibrations to electrical signals and arranged in bell-shaped vibration collecting structure |
WO2009155593A2 (en) * | 2008-06-20 | 2009-12-23 | Leonard Eisenfeld | Electronic stethoscope system |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3076870A (en) * | 1961-09-05 | 1963-02-05 | Navigation Computer Corp | Sound transducer system |
US3253228A (en) * | 1962-04-12 | 1966-05-24 | Aerojet General Co | Modulator-demodulator amplifier |
BE643118A (en) * | 1963-02-14 | 1964-05-15 |
-
1966
- 1966-10-10 GB GB50427/66A patent/GB1205569A/en not_active Expired
-
1967
- 1967-07-12 US US652892A patent/US3562428A/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0228178A2 (en) * | 1985-12-27 | 1987-07-08 | TDK Corporation | Displacement sensor |
EP0228178A3 (en) * | 1985-12-27 | 1988-07-06 | Tdk Corporation | Displacement sensor |
Also Published As
Publication number | Publication date |
---|---|
US3562428A (en) | 1971-02-09 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PLE | Entries relating assignments, transmissions, licences in the register of patents | ||
PLNP | Patent lapsed through nonpayment of renewal fees |