摘要 |
A threaded self-locking fastener, having a hollow body open at both ends and an elongated central through bore with a slot extending the length of the hollow body. Version 1 has sharp edges on the slot that dig into the bore of the work piece to prevent rotation. The fastener is used in conjunction with an internal driver. The driver located in the bore of the fastener engages detents to produce rotary drive motion. The driver also has a means of manipulating the first and second edges to facilitate assembly and disassembly. Version 2 has curved or chamfered edges in the slot and inward facing lobes also used in association with a driver. Rotation of the driver against the lobes causes the tubular fastener to be reduced in diameter against spring tension thereby allowing the fastener to freely rotate in the threaded bore of the work piece. By releasing the driver, the fastener expands and self locks in the threaded bore. Version 3 has a sharp edge on one side of the slot and a curved lobe on the other and is spring tensioned to cause the sharp edge to dig-in and prevent counter-clockwise rotation. The driver located in the bore of the fastener engages a detent causing the fastener to be reduced in diameter against spring tension when the driver is rotated clockwise. By releasing the driver's rotation, the fastener expands and causes the sharp trailing edge to dig-in to prevent counter-clockwise rotation of the fastener in the threaded bore of the work piece.
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