Vertical lifting mechanisms can be categorized by transmission method into hydraulic and mechanical transmission, and by structural form into cross-scissor type and sleeve type. Cross-scissor type mechanisms use a cross-arranged, hinged linkage frame structure to form a scissor shape. Lifting motion is achieved by changing the angle of the linkage crossing. This angle can be changed by the extension and retraction of the hydraulic cylinder piston rod or the retraction and release of the wire rope. Sleeve type mechanisms include truss, box, or cylindrical types, achieving lifting motion through the extension and retraction of multiple sleeve sections. The drive method can be hydraulic transmission or wire rope pulley transmission. This type of vertical lifting mechanism has a limited working height and a small working range, but a large working platform and stable support.
Lever-lifting mechanisms can be categorized into telescopic boom type, straight boom type, folding boom type, articulated boom type, and hybrid boom type, which are currently the mainstream lifting mechanism forms. Telescopic boom type lifting mechanisms consist of a multi-section, telescopic box-shaped boom, including a basic boom and a telescopic boom. The telescopic boom can be one or more sections, with hydraulic cylinders installed between each section. When the hydraulic cylinders operate, each boom section slides up and down along guide elements under the push of the cylinder piston rod, thus changing the boom length. Folding boom lifting mechanisms are composed of multiple box-shaped boom sections folded together, and can be divided into upward-folding and downward-folding types. The folding and unfolding of each boom section is accomplished by hydraulic cylinders between the sections. They can perform operations at a certain height and range; the downward-folding type can perform operations below ground level. Hybrid boom lifting mechanisms combine the advantages of folding and telescopic booms, increasing the working height and range, and possessing strong obstacle-crossing capabilities.
