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:
Jul. 19, 1983
Filed:
Mar. 10, 1980
Joseph A Rocci, Jr, Palos Heights, IL (US);
Other;
Abstract
Portable apparatus for testing the quality of a ground connection between the ground prong of a tool plug and the tool housing, and for testing the quality of insulation between the tool plug power prongs and the tool housing. The apparatus comprises an enclosure having a plug at one end adapted to be received into a conventional utility wall outlet and a receptacle at the other end for receiving a tool power plug. A pair of electrical contact plates are provided as two adjacent outside walls of the enclosure. Threshold detection circuitry carried internally of the housing is connected to the power and ground receptacles of the apparatus plug and to the contact plates. A first portion of the circuitry is effective for measuring the resistance between the ground prong of a tool plug inserted into the apparatus receptacle and a tool housing in physical contact with one of the contact plates. A second portion of the circuitry is effective for simultaneously measuring the resistance between the tool plug power prongs and the tool housing. LED's are connected to the measuring circuitry and observable by a user for indicating safe or unsafe ground or insulation quality.