Patent ID: 11643017

Abstract:
A linkage assembly including first, second, third, fourth and fifth elongate linkage members 12, 14, 16, 18 and 20 respectively, a first connecting arrangement 22 for connecting and allowing pivotal displacement between proximal end regions of the first and second elongate linkage members 12 and 14 respectively, a second connecting arrangement 24 for connecting and allowing pivotal displacement between distal end regions of the first and third elongate linkage members 12 and 16 respectively, a step support connecting arrangement 26 for connecting the first and fourth elongate linkage members 12 and 18 respectively, the step support connecting arrangement 26 being located inwardly the second connecting arrangement 24 and provides a stepping formation 30 for a user, the step support connecting arrangement 26 including a shaft 32 having a first portion 34 which is shaped to be received by and inhibit relative pivotal displacement between the fourth linkage member 18 and the stepping formation 30 during extension and retraction of the retractable ladder arrangement 36 and a second portion 38 shaped to be received by and allow pivotal displacement between the first and fourth linkage members 12 and 18, and a third connecting arrangement 28 for connecting and allowing pivotal displacement between the first and fifth elongate linkage members 12 and 20 respectively, the fifth elongate linkage member 20 being located intermediate the first and step support connecting arrangements 22 and 26 respectively.