Patent ID: 8297022

Claim:
A portable containment structure comprising: (a) a support frame having an upper side, a lower side and a perimeter, the perimeter defining a central opening; (b) an enclosed containment compartment attached to the upper side of the support frame, the containment compartment having a bottom opening which is in communication with the central opening in the support frame; (c) at least three wheels attached to the support frame, the wheels being operatively adapted to facilitate lateral movement of the support frame across a surface; and (d) wheel retractors for retracting each of the wheels upwardly with respect to the support frame which alternatively raise and lower the support frame between (i) a raised position wherein the support frame is disposed at a first elevation and can be laterally moved along a surface using the attached wheels, and (ii) a lowered position wherein the support frame is disposed at a second elevation which is lower than the first elevation and wherein the support frame is disposed in contact with the surface, each wheel retractor comprising a rotatable plate attached at one end to the hub of a wheel and pivotally attached at an opposite end to the support frame, such that each wheel can alternatively be rotated between (i) a first position wherein the support frame is disposed in the raised position and (ii) a second position wherein the support frame is allowed to assume the lowered position.