| 摘要 |
<p>Self-tightening nut (1) is positioned by rotating housing (10) relative to shaft (2) so as to engage nut (18) with thread (26). The shaft receiving aperture in upper housing (25) has an internal thread, so that continued rotation of housing (10) after lower housing (23) has abutted against member (6) stresses torsion spring (12). Lock nut (22) is screwed onto shaft (2) and is brought into tight frictional engagement with upper housing (25) so as to lock end (14) of spring (12) into a stationary position with respect to shaft (2). Spring (12) in its stressed state provides a torsional bias between lock nut (22) and nut (18). Should members (4 or 6) shrink, the force exerted by spring (12) will cause nut (18) to rotate down shaft (2) to prevent any loosening of the joint and so prevent any gap between fastened members (4, 6) and concrete (7).</p> |
