| 摘要 |
<p>Blind fastening means for fastening thin materials together without crushing them. Such means comprises a blind rivet sleeve, a blind rivet pin provided with a head to engage the blind end of the sleeve, and spacing means provided intermediate the blind end of the sleeve and the head thereof. As the head of the pin is drawn against the blind end of the sleeve an enlarged blind head forms at the blind side of the materials being fastened while the spacer means engages the interior side of the uppermost of the materials being fastened, whereby to prevent crushing of such materials. In one instance the spacer means comprises a spacer sleeve. In a modification the spacer means comprises a second enlarged blind head. The spacer means may be provided for by wiredrawing the main rivet sleeve, slotted or unslotted, interiorly thereof to form an enlarged head to pickup the top sheet. In a modification this interior enlarged head may be formed by wire-drawing a spacer sleeve, slotted or unslotted. In yet another modification the second or interior enlarged blind head may be achieved by providing slots or aress of weakness in the upper region of the blind rivet sleeve so that the material in such region offers less resistance to forming the enlarged interior blind head than does the sleeve material adjacent the lower blind head so that the upper, interior enlarged head will form first.</p> |
