Electronic pick-up device for transducing electrical energy and sound energy of the heart

• US 4,362,164 A
• Filed: 09/11/1980
• Issued: 12/07/1982
• Est. Priority Date: 09/11/1980
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Little, Michael J., Wong, Shi-Yin
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US06/186,074
• Time in Patent Office: 817 Days
• Field of Search: 128/639, 128/715, 128/773, 128/670, 128/671, 179/1 ST
• US Class Current: 600/382
• CPC Class Codes: A61B 2562/0215 Silver or silver chloride containing
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 7/026 comprising more than one sound collector

Abstract

A stethoscope transducer applicable as a conventional audio transducer and as a phonocardiogram transducer has a body which on one side mounts an electrode carrying chest bell and which on an opposite side mounts a conventional chest bell. A microphone and a rotor assembly are mounted in a cavity in the body. The microphone and earpiece connections on the body communicate through passages in the rotor assembly with the electrode carrying chest bell when the rotor assembly is in a first position and with the conventional chest bell when the rotor assembly is rotated to a second position. These are three electrodes, two being pickup electrodes which each occupy one quadrant of the chest bell rim in diametrically opposite positions. The third electrode is on the rim intermediate the pickup electrodes. The rim is of a non-wettable material providing a hydrophobic surface.

Claims

1. Apparatus including a stethoscope chestpiece, comprising:

a stethoscope body portion;

a chest bell having a base secured to said body portion and having a rim defining the open end of said chest bell, said chest bell being of electrical insulating material which is non-wettable providing a hydrophobic surface on said rim;

three metal electrodes disposed on said rim, two of said electrodes being electrical current pickup electrodes which are each circumferentially dimensioned to occupy substantially one quadrant of said rim in diametrically opposite positions on said rim and the third being a ground electrode intermediate said pickup electrodes on said rim and which is smaller than said pickup electrodes, said metal electrodes each being capable of forming a redox couple of the metal and a chemical commonly found on the surface of the skin;

said body portion having a passage therein opening through the base of said chest bell;

a microphone supported in said passage; and

utilization circuits electrically coupled to said electrodes and said microphone and including high input impedance circuit elements individually coupled to said pickup electrodes to be controlled thereby.

2. A stethoscope transducer applicable as a conventional audio transducer and as a phonocardiogram transducer, comprising:

a body portion defining a cavity including a cylindrical portion and having a pair of chest bells mounted thereon in substantially opposite positions, said chest bells communicating with said cavity through passages in said body portion extending radially of said cylindrical portion, each of said chest bells having a rim;

a rotor assembly having a cylindrical section rotatably disposed in said cylindrical portion of said cavity for rotatable movement between two positions and having two passages therein, one passage being a central passage extending centrally, axially through said cylindrical section of the rotor assembly and the other passage being a radial passage extending on one side only from said central passage, which radial passage couples said central passage with one of said body portion passages in each of said two positions, said rotor assembly having an external section, said central passage communicating with said cavity in said body portion at the end of said rotor assembly opposite said external section and dividing into two passages in said external section for receiving stethoscope earpiece connections;

electronic circuits in said body portion;

spaced electrodes on the rim of one of said chest bells electrically coupled to said electronic circuits for picking up electrical signals produced by heart action and useful in producing electrocardiograms when said electrodes are in contact with the body in the vicinity of the heart; and

a microphone disposed in said cavity in said body portion at said end of said rotor assembly opposite said external section to communicate with one of said chest bells in each position of said rotor assembly through said central axial and radial passages of said rotor assembly;

when said radial passage of said rotor assembly communicates with said one chest bell, said stethoscope transducer simultaneously produces electrical signals of the electrical activity of the heart and electrical signals of the heart sound activity by said microphone responsive to air pressure variations in said passages and said cavity, said electrical signals being useful in producing a phonocardiogram annotated by the electrical activity signal of the heart, and also communicates said air pressure variations to said divided air passages in said external section of said rotor assembly for use in audible heart signal detection and interpretation, and, when said radial passage of said rotor assembly communicates with the other of said chest bells, said stethoscope transducer simultaneously produces electrical signals of heart sound activity of said microphone for phonocardiogram display and communicates said air pressure variations to said divided air passages for audible heart signal detection and interpretation.