An accumulation pallet conveyor, for recirculating a plurality of pallets along an endless path, comprising two horizontal runs (1A, 1B) arranged parallel to, and superimposed upon each other, said runs being connected to each other by two curved portions (1C, 1D) situated at the opposite ends of the conveyor, said conveyor comprising: - a supporting structure; - an endless chain engaged on sprocket wheels which are rotatably mounted at the two opposite ends of said supporting structure about two mutually parallel horizontal axes; - motor means (M, R) for controlling the movement of said endless chain; - a plurality of pallet-carrying members guided on said supporting structure along said endless path; and - a plurality of pallets, each carried by a respective pallet-carrying member and adapted for conveying one or more components along the upper horizontal run of the conveyor, - wherein each pallet-carrying member comprises at least one sprocket wheel rotatably mounted on the pallet-carrying member with the interposition of a friction coupling, so that said sprocket wheel is adapted to engage without turning on said chain along the horizontal runs (1A, 1B) of the conveyor so as to force the pallet-carrying member to follow the movement of the chain, whilst said sprocket wheel is adapted to turn about its axis to enable the chain to continue to move with respect to the pallet-carrying member when the pallet-carrying member is stopped along the path, and - wherein the ascent and descent of each pallet-carrying member at the ends of the conveyor are caused by engagement on the chain of an engagement finger projecting from the body of the pallet-carrying member, said finger being adapted to engage the chain and to get coupled therewith in the curved portions (1C, 1D) at the two ends of the conveyor, said conveyor being characterized in that said engagement finger of each pallet-carrying member is slidably mounted along its axis with respect to the structure of the respective pallet-carrying member and is biassed against the chain by spring means set between the engagement finger and the structure of the pallet-carrying member in such a way that if a pallet-carrying member is blocked in position in the curved portion of the chain at one of the ends of the conveyor due to an involuntary interference with an operator or any other foreign bodies, the chain can continue to move freely with respect to said pallet-carrying member, causing a movement with multiple consecutive jumps of the engagement finger on the chain. - a supporting structure; - an endless chain engaged on sprocket wheels which are rotatably mounted at the two opposite ends of said supporting structure about two mutually parallel horizontal axes; - motor means (M, R) for controlling the movement of said endless chain; - a plurality of pallet-carrying members guided on said supporting structure along said endless path; and - a plurality of pallets, each carried by a respective pallet-carrying member and adapted for conveying one or more components along the upper horizontal run of the conveyor, - wherein each pallet-carrying member comprises at least one sprocket wheel rotatably mounted on the pallet-carrying member with the interposition of a friction coupling, so that said sprocket wheel is adapted to engage without turning on said chain along the horizontal runs (1A, 1B) of the conveyor so as to force the pallet-carrying member to follow the movement of the chain, whilst said sprocket wheel is adapted to turn about its axis to enable the chain to continue to move with respect to the pallet-carrying member when the pallet-carrying member is stopped along the path, and - wherein the ascent and descent of each pallet-carrying member at the ends of the conveyor are caused by engagement on the chain of an engagement finger projecting from the body of the pallet-carrying member, said finger being adapted to engage the chain and to get coupled therewith in the curved portions (1C, 1D) at the two ends of the conveyor,