Miniature, battery-powered cathode ray tube display heart monitor

• US 4,411,272 A
• Filed: 09/09/1981
• Issued: 10/25/1983
• Est. Priority Date: 09/09/1981
• Status: Expired due to Fees

• Current Assignee: Jerry A. Phelps Sr
• Original Assignee: Jerry A. Phelps Sr
• Inventors: Phelps, Jerry A. Sr.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US06/300,610
• Time in Patent Office: 776 Days
• Field of Search: 128/696, 128/701, 128/706, 128/708, 128/710, 128/712
• US Class Current: 600/524
• CPC Class Codes: A61B 5/30 Input circuits therefor
• CPC Class Codes: A61B 5/308 for electrocardiography [ECG]
• CPC Class Codes: A61B 5/7415 Sound rendering of measured values, e.g. by pitch or volume variation A61B5/741 takes precedence
• CPC Class Codes: G01R 13/20 Cathode-ray oscilloscopes

Abstract

A lightweight, small size, battery-powered cardioscope is provided which can be readily transported along with a patient whose heart is being monitored and conveniently mounted directly adjacent to the operating field. The cardioscope detects heart activity using conventional electrodes and includes an audio signal device for producing an audible beep for each heart-beat and a cathode ray tube display for displaying the detected cardiac electrical activity.

Claims

1. An cardioscope apparatus for detecting the electrical heart activity of a patient and for producing output in accordance therewith for presentation both by an associated cathode ray tube and an associated audio output device, said apparatus comprising:

electrode means, adapted to be connected to the body of a patient, for detecting the electrical activity of the patient'"'"'s heart;

a differential amplifier connected to said electrode means;

a diode shunt connected across the input of said differential amplifier to protect the differential amplifier from circuit overloads;

a passive 60 Hertz filter for filtering the output of said differential amplifier;

a further amplifier for amplifying the output of said filter;

a gain control circuit separate from said further amplifier for enabling continuous adjustment of the gain of the output of said differential amplifier;

a passive high pass filter connected to the output of said further amplifier;

a monostable multivibrator for receiving as an input thereto the output of said high pass filter;

a level detector for adjusting the input to said monostable multivibrator;

a gated oscillator, including a plurality of Nand gates, connected to the output of said monostable multivibrator;

an audio output device connected to the output of said oscillator;

a volume control circuit for adjusting the volume of the output signal produced by said audio output device;

a single ended push-pull amplifier connected to the output of said further amplifier for supplying a control voltage to the vertical deflection plates of the said associated cathode ray tube, and

power supply means, comprising only positive voltage batteries, for supplying the necessary supply voltages for the said associated cathode ray tube and the remainder of the circuitry for the apparatus, said power supply means including a voltage regulator for regulating the voltages supplied, said apparatus further comprising a horizontal sweep generator connected to said power supply means and the horizontal deflection plates of the cathode ray tube and, including means for adjusting the horizontal sweep speed.