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. 14, 1989
Filed:
Sep. 21, 1987
Roger E Mitchell, Minneapolis, MN (US);
Other;
Abstract
A digital voltage and continuity test instrument for use by electricians is disclosed. AC, DC and continuity test functions are provided with the AC and DC test modes including auto-zeroing. In a continuity test mode the continuity of the probe leads or the continuity of a circuit may be detected and indicated with a zero-display value. With the probes open circuit in the continuity mode the display provides a reading proportionate to the battery voltage level of the instrument. The electrical test circuitry includes a resistive divider network connected between the test probes, an AC rectifier for demodulating AC voltages received from the resistor divider network and an analog to digital convertor for receiving DC voltages from the resistive divider network or from the demodulator for driving the display according to the magnitude of the received voltage. Strain relief is provided for the test leads and includes an eyelet having a first washer-like end and a second tubular portion for receiving a test lead. The tubular portion is crimped on the lead and the conductor is soldered thereto. The eyelet is positioned within the housing with the washer-like end is positioned near the housing lead aperture so that stress applied to the lead is applied to the inside of the housing through the eyelet.