Patent ID: 7874026

Claim:
A system for raising and lowering a bed comprising: a bed platform; a balanced movement system comprising a counterweight system and a coordinated timing structure, the counterweight system comprising a plurality of counterweights connected to and acting on the bed platform through a like plurality of counterweight chains, the counterweight chains connecting the counterweights and the bed platform by traversing a like plurality of counterweight sprockets located on at least two rotatable shafts, the counterweight chains having their own weight that creates a weight differential that opposes movement of the bed when force is applied to the bed to change its resting position, the timing structure comprising at least two timing sprockets and a timing chain, each timing sprocket located on one of the two rotatable shafts configured opposite each other, the timing chain being looped around both timing sprockets in a figure-eight arrangement thereby coordinating the movement of the two rotatable shafts such that they rotate in opposite directions at substantially the same angular velocity.