Abstract: In a pneumatic conveyor for coins comprising a plurality of conduits leading from a plurality of payment points, a common conduit into which said plurality of conduits feed, a separator receiving coins from said common conduit and separating said coins from air, suction means for creating a suction in said common conduit and said plurality of conduits to convey coins to said separator, and a storage receptacle for receiving coins from said separator; the improvement comprising a sealing means for opening and closing concealing means disposed in each of said plurality of conduits for opening each of said plurality of conduits only when a coin enters one of said plurality of conduits and for closing the associated said one of said plurality of conduits after said coin has passed said sealing means, thereby to preserve said vacuum both in said plurality of conduits downstream of said sealing means and in said common conduits.