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:
May. 18, 1993
Filed:
Feb. 07, 1992
James G Johnson, Merrillville, IN (US);
Nabil L Mina, Roselle, IL (US);
Appleton Electric Company, Chicago, IL (US);
Abstract
An interlock mechanism operably associated with the plug receptacle of an explosion-proof housing whereby a plug may be inserted into or removed from the receptacle only when electrical current is not delivered to the receptacle. The interlock mechanism comprises a safety shaft for engaging a plug inserted into the receptacle, a reciprocating shaft operatively connected to a circuit breaker handle, and a locking pin for securing the safety shaft in a standby position, whereby the circuit breaker handle cannot be moved unless the safety shaft engages the plug casing, the safety shaft cannot be disengaged from the plug casing unless the circuit breaker handle has been moved to an off position, and the safety shaft will not engage the plug casing until it is released by the locking pin after the locking pin is biased to its disengaged position by the inserted plug.