Pantographs, or 'Scissor mechanisms'
A pantograph, or scissor lift, is a type of platform which moves vertically rather than horizontally. It uses linked, folding supports in a criss-cross pattern. When pressure is put on the lowest supports, the cross struts are stretched out, pushing the top platform upwards. Often, a platform is fixed to the top of the structure, to allow for loads.
The driving mechanism for a pantograph can be hydraulic, pneumatic or mechanical (a leadscrew or rack and pinion system).
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