Reversal protection for RLC defibrillator

• US 4,168,711 A
• Filed: 06/08/1978
• Issued: 09/25/1979
• Est. Priority Date: 06/08/1978
• Status: Expired due to Term

• Current Assignee: American Optical Corporation
• Original Assignee: American Optical Corporation
• Inventors: Cannon, Robert L. III, McEachern, Robert A.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/913,705
• Time in Patent Office: 474 Days
• Field of Search: 128/419 D
• US Class Current: 607/5
• CPC Class Codes: A61N 1/3931 Protecting, e.g. back-up systems

Abstract

A defibrillator, or alternatively, paddles therefor adapted with the wave-forming inductance of the discharge circuit disposed between the two paddles of the discharge circuit of the defibrillator and is so disposed in the paddles as to couple in a cancelling manner when the paddles are placed face-to-face. In a preferred embodiment, the waveform inductance is split substantially equally in each of the two paddles wherein each of the inductors have a value of substantially half the total necessary inductance for the forming of the waveform for the defibrillating wave.

The respective coils of the inductors are wound in reverse directions, one with respect to the other so that the total inductance generated in a discharge directly through the paddles is substantially nil.

Claims

1. In apparatus for cardiac therapy including defibrillator means having a capacitor, a charging source for said capacitor, a discharge circuit for said capacitor including a pair of electrodes adapted to apply the discharge of said capacitor to a patient, a wave-shaping inductor disposed in said discharge circuit, switch means for selectively connecting said capacitor to said charging means or said discharge circuit;

the improvement comprising the inclusion of at least a portion of said inductive discharge wave-shaping means disposed in one of said patient electrodes, and at least a portion of said inductive discharge wave-shaping means disposed in the other of said patient electrodes, said inductances being disposed such that their individual inductive coils are oppositely wound and flux fields opposing when shorted together.

2. In a patient electrode for connection to a defibrillator having a capacitor, a charging source for said capacitor, a discharge circuit for said capacitor including a wave-shaping inductor, switch means for selectively connecting said capacitor to said charging means or said patient electrode, the improvement comprising wave-shaping inductance disposed in said patient electrode, said inductance being wound in a predetermined first direction and being adapted to inductively couple with wave-shaping inductance disposed in a second patient electrode having inductance being wound in a predetermined second direction so that when said electrode is shorted to said second electrode the inductive fluxes oppose and tend to cancel the wave shaping inductance.

3. The improvement according to claim 2 wherein said first inductance and said second inductance are in a ratio of from 1:

1 to 1.15;

0.85.