| 摘要 |
<p>Case 4035 ROTARY FASTENER A rotary fastener is disclosed for use in attaching the first panel to a second panel. The fastener has a head and a shank, which shank has at least one helical thread thereon. Additionally, there is at least one helical ramp extending along the shank from the underside of the head. The underside of the head has a generally annular recess which may have helical ribs therein. The fastener is dimensioned so that as it is driven into the two panels, material of the two panels is drawn up into the recess and binds on the helical ramp along the shank. Additionally,a plurality of nibs located on the underside of the head and extending into the recess "rake" up material as the underside of the head encounters the top panel, which raked material is also drawn into the recess and binds on the helical ramp. This combined binding action by panel material and raked material significantly increases stripping torque of the fastener during installation.</p> |
