05253891 is referenced by 19 patents.

A safety interlock mechanism requires a trailer tow bar to be raised and placed into the mechanism before an electrical power supply cable can be removed from the mechanism and attached to an aircraft. Similarly, the electrical cable must be disconnected from the aircraft and placed into the interlock mechanism before the tow bar can be removed and placed onto a tractor for movement of the ground power unit. The safety interlock mechanism includes a hinged plate, which, in one position, prevents the removal of the electrical cable connector when the tow bar is not in place, and when in another position, prevents the removal of the tow bar when the electrical cable connector has been removed. Locking tabs engage the electrical connector whenever the tow bar has been removed. A locking pin engages a U-bolt attached to the tow bar whenever the electrical connector has been removed.

Title
Safety interlock mechanism for aircraft ground power units
Application Number
7/976433
Publication Number
5253891
Application Date
November 13, 1992
Publication Date
October 19, 1993
Inventor
Jerry L Besecker
Covington
OH, US
Brian J Hicks
Arcanum
OH, US
John K Carlin
Troy
OH, US
Agent
Biebel & French
Assignee
Hobart Brothers Company
OH, US
IPC
B60R 16/00
B60D 1/62
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