04368995 is referenced by 17 patents and cites 5 patents.

A loose-leaf binder has a cover and a ring mechanism. The ring mechanism includes a resilient base plate with curled edges and at least one rib extending laterally and downwardly. The ring mechanism also includes a pair of blades beneath the base plate and between the curled edges, the combined width of the blades being slightly greater than the distance between the curled edges. Also, the blades each have at least one slot along their outside edge to engage the rib. At least one pair of ring members fixed to the blades extend above the base plate to meet in a releasable juncture.

Title
Ring mechanism for loose-leaf binders
Application Number
6/190072
Publication Number
4368995
Application Date
September 23, 1980
Publication Date
January 18, 1983
Inventor
Lewis Cohen
205 The Bridle Path, Don Mills, Ontario
CA
Agent
Laff Whitesel Conte & Saret
IPC
B42F 13/20
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