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:
Dec. 08, 1992
Filed:
Oct. 30, 1990
John N Dukes, Los Altos Hills, CA (US);
Alan P Greenstein, Menlo Park, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A system for tracing uterine contraction is disclosed. The system comprises a probe and an electronics module. The electronics module includes a drive circuit and an output section having a frequency counter. The output section also includes a strip-chart recorder driven by a frequency-to-voltage converter. The probe includes an electro-mechanical transducer which is driven at resonance by the action of the drive circuit. When the probe contacts the abdomen of a pregnant subject, changes in the mechanical impedance of bodily tissue during a contraction affect the resonant frequency of the probe and thus the frequency output by the drive circuit. This frequency can be read directly from the frequency counter and recorded on the strip-chart so that contractions can be traced.