A device for coating sheet-type substrates, in particular glass panes, in a vacuum coating system is described. The system includes a) a series connection of chambers, through which each substrate sheet passes and which are arranged on the entry side, namely a load lock chamber, a buffer chamber and a transfer chamber, each of which is vacuum-sealable by a check valve. An area of process chambers follows the transfer chamber and the process chamber is followed by a transfer chamber, buffer chamber and load lock chamber. The system also includes b) a conveyor device; c) a vacuum pump with an adapter flange in the region of the buffer chamber; d) at least two flow baffles in the buffer chamber; e) a system for the longitudinal and height displacement of the flow baffles; and f) an assembly for controlling the dynamic processes.