摘要 |
This invention relates to a screw lock, characterized in that the screw key screws into a keyway, and the slots on the top ring screw of the screw key provide a convex-concave match with switch points in the cylinder. The screw key is then pushed in and turns the cylinder to effect locking and unlocking. The keyway of this invention is adapted to accept the spiral screw shape, and accordingly, the form and the mechanism of the switch points are not seen. Thus, the form and mechanism of the switch points in the cylinder is unknown. Also, conventional keys or wires cannot be inserted into the spiral screw hole. In case other keys are inserted into the keyway, the set points in the cylinder prevent the key form being further pushed in and prevent turning of the cylinder to effect unlocking.
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