| 摘要 |
<p>The adjustable latch bolt of this invention features a novel cam actuating assembly which permits election of one of two door knob spindle backsets which are in standard usage. The cam assembly is comprised of two half hubs, each having one arm so that one half hub operates the drawbar in one direction of rotation and the other in the opposite direction of rotation. The half hubs are formed so that a portion of one half hub nests in a depression in the other in such a way that the two half hubs can rotate relative to each other. When the hubs are set to one of two backsets and are in a position to actuate the drawbar, non-circular openings passing through the axis of rotation of the two hubs are aligned so that a complementary shaped spindle can pass through both hubs and engage them for rotation. With the spindle in place the two half hubs are prevented from rotation relative to each other. In this condition, the distance between the two arms is greater than the distance between detents on the drawbar and the cam assembly cannot be moved from one backset position to another. With the spindle removed the two half hubs can be rotated relative to each other so that the distance between the arms is less than the distance between the detents on the drawbar and the cam assembly is able to pass between the detents from one backset position to another.</p> |
