Device for separating the top sheet of a pile of sheets

摘要

A suction piston is connected with a pump which generates a high/low pressure wave in a cylinder in which the suction piston is guided. At the end of the suction piston there is a suction mouthpiece, which lies on the top sheet of the pile of sheets in the rest position. The suction piston is arranged inclined at an angle of beta < 90 DEG to the surface of the pile. When the pump has been switched on, the top sheet is pulled upwards in the first suction phase. The suction piston reciprocates in the following high/low pressure phases. The sheet hanging on the rubber of the suction apparatus is thereby briefly released in the high pressure phase and attracted in the following suction phase. This pushes it forwards, until it abuts against the pair of draw-in rollers. A diaphragm or reciprocating pump may be used as a pump. Return valves and flow resistances can be incorporated in the pump cover, to enable the length of the phase of the high/low pressure wave to be set.