Transducer for bioacoustic signals
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Accused Products
Abstract
In well-known electronic stethoscopic transducers the sensitive element is influenced by signals transmitted via the skin, and the rear side is enclosed in a housing to prevent airborne noise from reaching the sensitive element. According to the invention, an improved signal-to-noise ratio is obtained by letting the transducer be a piezoelectric transflexural diaphragm in contact with the skin, the rear side of the diaphragm communicating with the surronding air via an acoustical network, thereby receiving airborne noise which acts to counteract the influence of noise coming from the skin.
33 Citations
30 Claims
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1-15. -15. (canceled)
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16. A transducer for bioacoustic signals, comprising:
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a transducer element having a front side and a rear side, the front side being adapted for establishing intimate contact with a surface of a body part receiving direct interior sound from the body, said transducer element being mounted in a housing subject to airborne noise, and having a surface surrounding the front side of said transducer element, said transducer element and said surrounding surface being in intimate contact with the surface of said body part during use, wherein the transducer element has an effective area that is less than 50% of the area of the surrounding surface of the housing, and wherein the rear side of the transducer element is loaded by acoustical network means which are in communication with the surrounding air, said loading creating an extinguishing relationship between airborne noise signals influencing the front and rear sides of the transducer element, respectively. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
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Specification