05183173 is referenced by 49 patents and cites 57 patents.

A fuel cap for closing a threaded filler neck of a fuel tank is disclosed. The can has a central button or driver which reciprocates within an opening in the crown of the cap. When the cap is installed on a filler neck, the driver is in an upper position and the crown freely rotates relative to the threaded housing in a cap-removal direction. When the driver is depressed, a pressure relief valve is opened and a driving relationship is created between the crown and the threaded housing in a cap-removal direction, permitting the cap to be removed from the filler neck. When the crown is rotated in a cap-installation direction, the driver is moved to the upper position and the pressure relief valve is closed.

Title
Auto venting fuel cap
Application Number
7/737220
Publication Number
5183173
Application Date
July 29, 1991
Publication Date
February 2, 1993
Inventor
Greg A Heckman
Dixon
IL, US
Agent
Allegretti & Witcoff
Assignee
Epicor
IL, US
IPC
B65D 51/00
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