04245545 is referenced by 28 patents and cites 11 patents.

A toggle-bolt-like blind-end connector fastens sheet-metal panels to fiber-board ducts by passing through pre-bored holes in the metal panel and punching its own hole in the fiber-board by a sharply pointed conical head mounted on a barbed-ring shaft. An expandable spider is fixed at the base of the head and is held collapsed against the shaft by a short sleeve. The sleeve has an end flange to limit its following the head and spider through the hole punched in the fiber-board, thus allowing the spider to expand inside the duct, after which expansion the shaft is pulled outwardly to press the expanded spider against the inner surface of the fiber-board. Next a resilient-material nut having shaft-gripping barbed-rings in its bore is pushed onto the exposed end of the shaft to engage the sheet-metal panel. The barbed-rings on the shaft facilitate breaking-off the unneeded end of the shaft.

Blind-end connector for fastening sheet metal to fiber-board ducts
Application Number
Publication Number
Application Date
January 26, 1979
Publication Date
January 20, 1981
James D Freeman
11 W. Grand Ct., Springfield, 62704
Ralph F Staubly
F16B 13/08
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