| 摘要 |
<p>A lever lock includes an additional arrester member 16 to restrict the movement of a barrel-and-curtain member 11 in such a way that, in the locking condition with the bolt 3 extended, the barrel-and-curtain member cannot be turned to the extent which would enable the barrel slot 13 to face that region of the lever bellies 10 from which information on the key bit pattern might be derived by observation of the pattern of wear. The arrester member is in the form of a plate sliding in parallel with the bolt and linked to it through a lost-motion pin and slot coupling 18/19. When the bolt is being retracted by the correct key the arrester member is also freed for retraction and is driven back by abutment with the turning curtain portion 14. Subsequent return movement of the arrester member when the bolt is extended occurs through the pin and slot coupling 18/19.</p> |
