Patent ID: 8172254

Claim:
A collapsible frame structure movable between an unfolded position for use and a folded position for storage, the frame structure comprising: a front frame disposed on a front of the frame structure and comprising a plurality of first frame members; a rear frame disposed on a rear of the frame structure and comprising: a plurality of second frame members; and a hub that pivotably connects the plurality of second frame members; wherein at least two of the frame members connect the hub to the front frame; a pair of tension rods connected to the front frame; an locking mechanism movable between an engaged position and a disengaged position for locking said front and rear frames in the unfolded position, said locking mechanism comprising: a base member pivotably connected to the hub; and a lever connected to the pair of tension rods, and configured to releasably attach to the base when the locking mechanism is in the engaged position, and to detach from the base when the locking mechanism is in the disengaged position; and wherein the locking mechanism is configured to apply tension to the tension rods and pulls the front and rear frames towards each other to maintain the frame structure in the unfolded position when the base member and lever are engaged.