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:
Feb. 04, 1997
Filed:
Dec. 28, 1994
Herman L Renger, Calabasas, CA (US);
Pacesetter, Inc., Sylmar, CA (US);
Abstract
An implantable blood flow sensor for measuring a blood flow rate through a blood vessel within a person's body. The flow sensor includes a rigid cylindrical tube, sized to fit within the blood vessel, a heater attached to the tube, and a pyroelectric detector located within the tube. A predetermined amount of heat energy is produced by the heater and the pyroelectric detector monitors the resultant temperature change and generates a temperature signal based on the temperature change. A processor generates a data signal, based on the temperature change, that indicates the blood flow rate through the blood vessel or artery. The rigid tube protects the pyroelectric detector from external forces that may produce unwanted signals due to piezoelectric effects. Additionally, the heater may be incorporated into one of the electrodes of the pyroelectric detector as a serpentine path in the electrode that forms a resistive heating element. Also, a switch may be provided that prevents induced voltage signals caused by currents through the heater from reaching the processor.