An overhead conveyor (OHC) is a material handling system consisting of a continuous chain running beneath a rail. Individual carriers, spaced along the length of the conveyor are suspended from the chain. The chain pulls the carriers. The load is hang up on the rail by trolleys.
Overhead conveyors are used to maximize space, sort, buffer, and distribute, and is one of the most economical methods of conveying while maximizing floor space.
We speak about a regular OHC when the load is directly connected with the chain. On the contrary, a Power & Free system, has a disconnection between the load and the chain.