A variable-capacity store for objects, wherein an endless conveyor defines a conveying branch, for conveying a mass of objects, and a return branch, which respectively form a first and a second spiral of given lengths, each of which coils about a respective fixed first drum and a respective second drum movable to and from the relative first drum; and wherein the second drums are located on the same side with respect to the relative first drums, and are connected to each other by a transmission powered by a single reversible motor to equally and oppositely adjust the distances between the second drums and the relative first drums.