| 摘要 |
<p>A lock comprising a day bolt (1) and a night bolt (2), said day bolt (1) being urged by a spring (8) to an extended locking position and being retractable by a handle-operated tumbler (5) to a releasing position, said night bolt (2) urged by a spring to a retacted releasing position, and being lockable both in an extended locking position and in the retracted releasing position by a packet of tumblers (14) adapted to be swivelled by means of a suitable key to a position wherein the locking of the night bolt (2) is removed, thereby rendering it freely slidable. For swivelling the packet of tumblers (14) there is provded a tumbler tripper (20) having an arm (21) projecting from the lock housing (4), said arm being retainable by an energized electric magnet (25) in a position wherein the tripper (20) is out of engagement with the tumblers (14) and wherein, as soon as the current supply to the electric magnet (25) is interrupted, the tripper (20) is swivelled by an associated biasing spring (24) to a position wherein it moves the tumbler packet (14) to the night-bolt-releasing position without interfering with the operation of the day bolt (1). </p> |
