Audio cardioscope

Claim 1

AN AUDIO CARDIOSCOPE OR ELECTRIC STETHOSCOPE, COMPRISING AN ELECTROMAGNETIC MICROPHONE TRANSDUCER TO BE PLACED AGAINST A HUMAN BODY BEING EXAMINED, SAID TRANSDUCER INCLUDING A MAGNETIC CORE, A VIBRATABLE ARMATURE, AND A COIL ON THE CORE TO DEVELOP AN OUTPUT VOLTAGE IN RESPONSE TO VIBRATION OF THE ARMATURE; AN AMPLIFIER TO BE ENERGIZED BY THE OUTPUT VOLTAGE FROM SAID TRANSDUCER AND SERVING TO DEVELOP AN AMPLIFIED OUTPUT SIGNAL RELATED TO THE FREQUENCY OF THE OUTPUT VOLTAGE FROM THE TRANSDUCER; A HEAD-PHONE RECEIVER TO BE ENERGIZED BY THE AMPLIFIED OUTPUT SIGNAL FROM SAID AMPLIFIER; AND MEANS SUPPORTED ON AND ASSOCIATED WITH SAID VIBRATABLE ARMATURE OF SAID TRANSDUCER FOR PHYDICALLY COUPLING THE MASS OF THE HUMAN BODY TO SAID ARMATURE DURING AUSCULTATION OF SAID HUMAN BODY, SAID MEANS INCLUDING A BUTTON OF SOUND CONDUCTING MATERIAL SUPPORTED CO-AXIALLY ON SAID VIBRATABLE ARMATURE AND SHAPED TO HAVE A FRONT END OF RELATIVELY POINT FORM FOR ENGAGING SUCH HUMAN BODY, AND FURTHER INCLUDING A PRESSURE PLATE HAVING A BORE CO-AXIAL WITH THE POINT OF SAID BUTTON TO LIMIT THE AMOUNT OF PROTRUSION OF THE ENGAGED SKIN AXIALLY AGAINST SAID BUTTON, AND FURTHER INCLUDING MEANS FOR LIMTING INWARD AXIAL MOVEMENT OF SAID BUTTON TO MAINTAIN AT LEAST A MINIMUM AIR GAP BETWEEN SAID ARMATURE AND THE CORE.