| 摘要 |
<p>A releasable snib mechanism for a door latch assembly includes a body (19, 19a), and a first rotary member (30) disposed in the body and adapted to be engaged by and rotated with a door latch spindle. A snib member (34) is mounted on the body for movement between a snibbing position in which the first rotary member (30) is snibbed against rotation and a freeing position in which the first rotary member is free to rotate with the door latch spindle. A second rotary member (32) is disposed in the body adjacent the first rotary member (30) and is adapted to be engaged by and rotated by a shaft means. This second rotary member (32) is arranged upon initial rotation of the shaft means to move the snib member (34) from its snibbing position to its freeing position and upon continued rotation of the shaft means to provide rotation to the first rotary member (30). According to one aspect of the invention the first and second rotary members include respective first (56) and second (66) formations which are disposed mutually adjacent when the rotary members (30, 32) are at a predetermined relative position, for cooperating with a complementary snib formation (54) on the snib member (34). The first formation (56) and snib formation (54) affect the aforementioned snibbing of the first rotary member and the second formation (66) is effective as camming means (68) during said initial rotation to act on the snib formation (54) to move the snib member to its freeing position. According to another aspect, means is provided to bias the rotary members to a predetermined relative rotational position, and this biasing means comprises a coil spring (36) disposed within the aforesaid body so as to be compressible by one or either of the rotary members (30, 32) when they rotate.</p> |
