Cover System For Open-Topped Containers

An arm assembly for a cover system includes a force mechanism associated within a hollow arm of the assembly that includes a resiliently compressible element, such as a compression spring or gas spring, connected to one end of a cable. The opposite end of the cable is fastened to a non-circular pulley mounted to the container body, so that the cable is wound around the pulley as the arm pivots relative to the container body. As the arm pivots in a stowed direction, energy is stored by the compressible element, and releasing the stored energy causes the arm to pivot toward an extended or deployed position.