| 摘要 |
A collapsible multi-purpose ladder has ladder stringers which are connected by joints which are arranged in pairs, can be locked in several operating positions, and each have two joint parts which are pivotal about a common joint axle. The first joint part has a two-cup locking disk which is concentric with respect to the joint axle and, along its circumference, has notches which are distributed to correspond to the various operating positions. The notches can receive a spring-loaded locking part which is guided for longitudinal movement on the second joint part, which grips over the first joint part. The locking part can be moved out of a notch of the locking disk by a release lever which is pivotally supported on the second joint part and the release levers of the two joints which are associated with the two ladder stringers are operatively connected by a rod. The locking part includes a lock member which is substantially rectangular, has a width which approximately equals the width of the second joint part, and is guided in slots in the sidewalls of the second joint part, includes a guide part having a width which is only slightly less than the inside width of the second joint part and a length which is greater than the width of the slots, and includes a guide rod for the spring. The slots are wider than the width of the lock member and each have a retaining surface which can hold the lock member in its disengaged position. The locking disk which has the notches has noses which face in the same direction, a respective nose lying next to each notch and forming a stop surface for the lock member. |
