A sofa-bed having an articulated folding structure
GB9008737D0
"folding framework for furniture which is convertible from a bed to a seat and vice versa"
EP0411233A1
Folding framework with four frames for sofa-beds and the like
EP0323809A1
Folding framework for sofa-beds and the like
FR2387006A1
Easy chair converting into bed - has five successive inter-hinging frames, opens in two stages, three hinges aligning to counter folded mattress forces
