Electric plug lock
Patent 5055057 Issued on October 8, 1991. Estimated Expiration Date: 
October 9, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 9, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2664734 2733416 3543544 Locking device for the prongs of an electrical plug Locking device for electrical plugs Patent #: 4030795 InventorApplicationNo. 593608 filed on 10/09/1990US Classes:439/134, Prong cover439/133, WITH UNAUTHORIZED CONNECTION PREVENTER, E.G., KEY OR COMBINATION LOCK439/149, Prong cover439/304Including lock for retaining means (e.g., key or combination lock or requiring "special" tool)ExaminersPrimary: Bradley, PaulaAttorney, Agent or FirmInternational ClassH01R 013/422AbstractA locking device for attachment to the male electric plug on the power supply line to an electric appliance, for the purpose of preventing use of the appliance, comprises a maximum of four separately molded plastic parts, two of which are identical and are secured together to form a housing containing one of the other two components, which is a unitary molded plastic spring locking member. The housing is provided with a pair of slots for receiving the prongs on the electric plug to be locked, and insertion of the prongs into the housing automatically effects the locking action. The device can be unlocked only by a key which is separate from the device, and which is the fourth component and is inserted through an opening into the interior of the housing to release the locking action. | |
