Patent ID: 8388005

Claim:
An apparatus comprising: a quadrilateral frame including a first and second vertical assembly, and a first and second collapsible horizontal assembly, the first collapsible horizontal assembly positioned above the second collapsible horizontal assembly, both horizontal assemblies to collapse vertically, the second horizontal assembly to further include: a first geared sub-assembly coupled to the first vertical assembly; and a second geared sub-assembly coupled to the first geared sub-assembly and the second vertical assembly, the sub-assemblies geared to maintain the angle between the first geared sub-assembly and the first vertical assembly equal to the angle between the second geared sub-assembly and the second vertical assembly; a front and rear wheel coupled to the quadrilateral frame; and a lever coupled to the second collapsible horizontal assembly of the quadrilateral frame, the second horizontal assembly to collapse in response to a force applied to the lever; the front and rear wheels capable of at least partially supporting the apparatus when the first and second collapsible assemblies are collapsed and extended.