| 摘要 |
<p>A latch assembly (1) of the kind having a latch bolt (3) which is mounted on a casing (5) for relative movement between an extended latching position and a retracted release position. The bolt is movable into the release position by operation of either one of two actuators (9, 12) which are accessible at inner and outer sides respectively of the latch assembly. The inner actuator includes a turn-knob or handle (9), and locking means (13, 14) associated with that actuator is operable to prevent operation of the inner actuator and thereby prevent retraction of the latch bolt (3) from the inner side of the assembly. The assembly includes lock release means (17) which responds to operation of the outer actuator (12) so as to deactivate the locking means (13, 14) and thereby release the inner actuator for normal operation. The locking means includes a spring loaded cam which influences the position of at least one detent and which is held in a locking means active position by retaining means which is responsive to operation of the outer actuator. That response involves the retaining means releasing its influence on the cam member so that it can be driven under the influence of the associated spring into a locking means inactive position.</p> |
