| 摘要 |
An automatic door latch has a case (14, 15) and a bolt (20) movable within the case (14, 15) between a fully extended position in which the bolt (20) extends forwardly of the case (14, 15) and a partially extended position in which the bolt (20) is positioned to contact a door strike. There is a plunger (24) mounted on the bolt (20), with the bolt (20) and plunger (24) being relatively movable. A spring (32) biases the bolt (20) toward a fully extended position and a spring (26) biases a plunger (24) outwardly of the case (14, 15). The plunger (24) has a projection which limits outward movement of the plunger to a position in which its extension is the same as that of the bolt (20) when it is in its partially extended position. There is a stop (56) on the bolt (20) movable toward and away from the case (14, 15) and there are projections on the case (14, 15) which coact with the bolt stop (56) to limit bolt (20) extension to its partially extended position. The plunger (24) has a cam (84, 86, 88, 90) cooperating with the bolt stop (56) to cause movement of the stop (56) away from the case (14, 15) and toward the bolt (20) during outward movement of the bolt (20) relative to the plunger (24) to permit the bolt (20) to move to a fully extended position. |
