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:
Apr. 14, 1981
Filed:
Jun. 01, 1979
Neal F Nordling, White Bear Lake, MN (US);
Cardiac Pacemakers, Inc., St. Paul, MN (US);
Abstract
An improvement in a demand-type heart pace system in which the normally high input impedance of the R-wave sensing amplifier is reduced for a predetermined time interval following the generation of a heart stimulating impulse such that the charge on the pulse generator's voltage doubling capacitor following the generation of the stimulating impulse may more rapidly be restored to thereby prevent false detection of naturally occurring R-waves. Following the predetermined time interval, the input impedance of the R-wave amplifier is again returned to a high value in anticipation of the receipt of a natural R-wave signal following the completion of a refractory period. Digital logic circuitry is utilized for controlling the conduction state of semiconductor switches which are connected in parallel with the resistors normally establishing the amplifier's input impedance and the recharge path for the voltage doubling capacitor.