| 摘要 |
<p>Disclosed is a fastener assembly for attaching articles to a penetrable wall comprising a threaded fastener having a threaded shank and an anchor member capturing the threaded shank. Means are provided for retaining the anchor member in a first position substantially parallel to the axis of and partially embracing the threaded shank while the fastener, carrying the anchor member, pierces the wall. The threaded shank has a length sufficiently greater than the length of the anchor member to allow the threaded shank to extend beyond both ends of the anchor member when the anchor member is in the first position. The anchor member further has spring means which, after the anchor member has passed fully through the wall, aids rotation of the anchor member from the first position to a second position substantially oblique to the axis of the threaded shank and wherein the shank and anchor member are in threaded engagement with each other. The threaded shank has at least two thread segments of different major diameters with the thread segment having the largest major diameter being first to pierce the wall during installation of the fastener assembly. When the fastener is subjected to a force in a direction to retract the fastener through the wall after spring aided rotation of the anchor member toward the second position and the anchor member is brought to bear against an inner surface of the wall, thereby positioning the fastener to be threadedly advanced through the anchor member, the threaded shank will be prevented by the largest major diameter threaded segment bearing against the anchor member, from pulling through the anchor member and allowing the anchor member to fall free.</p> |
