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:
Oct. 06, 1987
Filed:
Oct. 22, 1985
Francois Morin, Longueuil, CA;
Hydro Quebec, Montreal, CA;
Abstract
An ohmmeter for measuring very low electric resistances, for example the very low resistance of a very high current electric joint, which ohmmeter comprises a source for establishing a measuring current through the joint to thereby create a voltage drop proportional to the magnitude of the measuring current and to the resistance to be measured. A first integrator integrates a signal respresentative of the magnitude of the measuring current in order to produce a first integration signal, while a second integrator integrates the voltage drop proportional to the measuring current and to the very low resistance in order to produce a second integration signal. The two integrators are simultaneously reset to zero so that they both start their respective integrations at a same instant. The first integration signal is compared to a reference signal through a comparator. When the amplitude of the first integration signal reaches the amplitude of the reference signal, the comparator delivers a signal which stops the integration carried out by the second integrator. The second integration signal is then stored, this signal having an amplitude constituting a measure of the very low electric resistance. A display device receives the stored integration signal for displaying the value of the measured resistance.