Patent Publication Number: US-2011064236-A1

Title: Electronic stethoscope with narrow pickup beam

Description:
FIELD OF THE INVENTION 
     The present invention pertains to electrical or electronic stethoscopes, and more particularly to an electrical or electronic stethoscope which uses a single microphone utilizing narrow pickup beam technology. 
     BACKGROUND OF THE INVENTION 
     Electrical or electronic stethoscopes, which will be referred to hereinafter as electronic stethoscopes, have been proposed for diagnosing medical conditions. An electronic stethoscope uses a microphone to pick up acoustic inputs for subsequent diagnosis. 
     An important element of acoustic inputs is limitation of disruptive, unrelated noises from the environment. Various approaches have been developed to overcome disruptive environmental noises, such as suppression and filtering. An electronic stethoscope using two microphones has been proposed. The two microphones are movable so as to be able to approach and diverge from one another for focusing on a desired sound source area of the body. 
     SUMMARY OF THE INVENTION 
     The present invention provides an electronic stethoscope which utilizes a single microphone of a type having narrowly focused pickup beam characteristics. The novel stethoscope can obtain and transmit sounds obtained from very limited portions of the body, thereby eliminating or minimizing unrelated sounds which might interfere with acoustic characteristics of a sought organ or body area. The narrow pickup beam enables the head of the novel stethoscope to be tilted relative to the skin, so that for example, a pickup beam can be obtained from an organ or body area from which direct access or acoustic travel path is interrupted by an intervening entity or organ. Illustratively, the head of the novel stethoscope may be positioned below or above a rib, and may be inclined so as to pick up sounds from an area directly behind the rib, thereby overcoming acoustic obstruction by the intervening member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Similar reference characters denote corresponding features consistently throughout the attached drawings. 
         FIG. 1  is a perspective view of an electronic stethoscope according to at least one aspect of the invention. 
         FIG. 2  is an electrical schematic showing in simplified form electrical components of the stethoscope of  FIG. 1  and electrical connections thereof. 
         FIG. 3  is a perspective view of an electronic stethoscope according to a further aspect of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention is seen in overview in  FIG. 1  to comprise outwardly a stethoscope  10  having a pickup head or microphone  14  for acquiring sounds to be transmitted to the ears of the user (not shown). The microphone  14  may be of a type characterized by a narrow sound pickup beam, for obtaining acoustic inputs. The microphone  14  may be a horn microphone, may incorporate a parabolic reflector, may use directional filtering, or may be of any other known type which enables a single microphone to respond to a narrow sound pickup beam. 
     Referring also to  FIG. 2 , the novel stethoscope  10  is an electrical or electronic stethoscope since it uses an electrically powered sound system which produces signals responsive to the acoustic inputs. More specifically, the stethoscope  10  utilizes an input transducer (i.e., the microphone  14 ) to generate signals from acoustic inputs, and in turn to reproduce originally captured sounds from the input transducer using output transducers or speakers  16 A,  16 B. An electrical circuit generally indicated at  18  transmits signals generated by the input transducer or microphone  14  to the speakers  16 A,  16 B. Each speaker  16 A or  16 B is contained within a respective earpiece  20 A or  20 B. 
     In its physical configuration, the stethoscope  10  may generally resemble an ordinary pneumatic stethoscope (not shown, having an elongated flexible pickup tube  22 , two earpieces  24 A,  24 B which contain the speakers  16 A,  16 B respectively, and two elongated flexible speaker tubes  26 A,  26 B which extend to the earpieces  24 A,  24 B. 
     The electrical circuit  18  comprises an onboard battery cell or cells, which will be referred to as a battery  28 . The battery  28  is connected to the electrical circuit  18  so as to provide electrical power to the electrically powered components, such as the microphone  14  and the speakers  16 A,  16 B. The electrical circuit  18  includes an on-off switch  30  disposed to control electrical supply communication between the battery  28  and the rest of the electrical circuit  18 . 
     A volume control feature disposed to selectively adjust sound volume of the acoustic signals may be incorporated into the electrical circuit  18 . For example, a variable voltage switch  32  may control power to the speakers  16 A,  16 B. 
     The stethoscope  10  may comprise an onboard sound recorder  34  for recording the acoustic signals. Where provided, the onboard sound recorder  34  is powered by the battery  28  by suitable connection to the electrical circuit  18 . The onboard sound recorder  34  may have operating functions of for example known tape recorders and other recording devices (none shown), such as an on-off control, volume control, playback control, and the like. The onboard sound recorder  34  may have manual controls  36 . Suitable controls (not shown) may be provided as part of the onboard sound recorder  34  or may be separately provided. 
       FIG. 3  shows an option wherein a stethoscope  110  according to a further aspect of the invention has a recorder  134  which is separate or detachable from the rest of the stethoscope  110 . In all other respects, the stethoscope  110  may be the structural and functional equivalent of the stethoscope  10  of  FIG. 1 . The stethoscope  110  may have a signal port  136  to which a connection such as a communications cable  138  of a separate recording device  140  may be connected to record acquired sounds. This option enables a user to purchase the stethoscope  110  at less cost than that of the stethoscope  10 , if the user saw no need for a recorder. 
     While the present has been described in connection with what is considered the most practical and preferred embodiments, it is to be understood that the present invention is not to be limited to the disclosed arrangements, but is intended to cover various arrangements which are included within the spirit and scope of the broadest possible interpretation of the appended claims so as to encompass all modifications and equivalent arrangements which are possible.