Collapsible hoisting apparatus

摘要

A collapsible hoist apparatus includes a lower boom assembly, a middle boom assembly, and an upper boom assembly, the boom assemblies consisting of two parallel boom arms and a transversal crossbeam, and are connected to one another by a pivotal annular support. The annular support allows the complete boom assembly to be placed in a first extended position, such that the boom assemblies extend outwardly, aligned in a pleated configuration; a fully extended position, such that the boom assemblies extend outwardly, aligned in a planar configuration; or a closed storage position, such that the boom assemblies extend inwardly, aligned in a pleated configuration.

主权项

1. A collapsible hoisting apparatus, said apparatus comprising:
a lower boom assembly coupled to a mounting assembly by at least one pivotal annular support, a middle boom assembly, and an upper boom assembly, said boom assemblies together comprising a complete boom assembly, and said boom assemblies each including two parallel boom arms and a transversal crossbeam, and each connectible to one another by the at least one pivotal annular support, said pivotal annular support pivoting on an axis; wherein the upper boom assembly includes the at least one pivotal annular support on each boom arm at a proximal end, and a cable-pulley assembly from which to hoist a load from underneath the upper boom assembly on a distal end, further wherein the at least one pivotal annular support allows the complete boom assembly to be placed in a first extended position, a fully extended position, or a closed storage position, and further wherein the at least one pivotal annular support each comprises two cylindrical plates, one plate mounted on each end of each boom arm of the lower boom assembly and one plate mounted on each end of each boom arm of the middle boom assembly.