The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 01, 1977
Filed:
Nov. 19, 1974
Richard J Ravas, Monroeville, PA (US);
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Abstract
A DC pulse generator, specifically suitable for application as a cardiac pacemaker having a substantially constant energy output which is independent of the output load. The output pulse is derived from a capacitive reactance which is partially discharged to a preselected reference level. The cyclic rate of discharge is maintained substantially constant, and accordingly, the pulse width is varied to assure a constant energy output to the load. The capacitive reactance is charged in between output pulse periods from a matched impedance radioisotope thermoelectric source through a constant current inverter, step-up transformer, voltage doubler, inverter network. The oscillator controlling cyclic discharge of the capacitance through the load and the inverter, which is arranged in a push-pull configuration, is designed to be self-starting to avoid stall conditions during operation. Furthermore, the discharge rate is substantially independent of the DC level and provides a negative rectangular output pulse. In the event external defibrillator pulses are applied, means are provided to conduct resulting current impulses directly into the capacitive reactance which can safely absorb the energy, thus avoiding failures in the internal circuitry elements.