| 摘要 |
<p>The composite fastener comprises a metal screw and a plastic head. The metal screw includes a threaded shank, a tool engageable metal head, a scalloped washer adjacent the metal head and a shoulder connecting the washer to the threaded shank. The plastic head encapsulates the metal head and washer and includes a tool engageable portion and a washer portion extending around and in between the scallops and terminating at the shoulder. The tool engageable plastic portion preferably has a cylindrical central section encapsulating the metal head and at least two ribs extending radially outward from the cylindrical section along the washer portion, the ribs forming the tool engageable portion. The ribs may be tapered in either or both of two directions and/or may be structured to shear off at predetermined torques.</p> |
