摘要 |
<p>A helically coiled wire-type screw thread insert, of the type used for tapped holes in workpieces in which a fastener component is threaded into, is provided. The two free end coils (12A, 12B) each have a hook means recess (14) on the inner screw thread of each, and the terminal end (16A, 16B) of each free end coil (12A, 12B) has a reduced transverse cross-section or a diminishing cross-sectional area construction. Further the outer thread pitch diameter (P1) of the free end coils (12A, 12B) is preferably less than that of the remaining coils (13 min ). The invention provides improved insertion capability and provides a removal capability unknown in the screw thread inserts of the prior art.</p> |