Abstract: A buffer store for a flat web material includes two roller registers having freely rotatable rollers movable relative to one another in a direction radial to a roller axis, thereby forming loops of the web material between the rollers, a piston-cylinder arrangement having a chamber containing a compressible medium and acting as a spring between the registers to generate web tension in the material, and a control-valve arrangement that switches between a first condition, for normal operation, and a second condition, for operation during a fault. In the first condition, the control-valve arrangement connects the cylinder chamber of the piston-cylinder arrangement to a device for providing a constant operating pressure. In the second condition, the control-valve arrangement closes the cylinder chamber of the piston-cylinder arrangement and connects it to a relief valve that relieves pressure therein to a residual pressure significantly smaller than the operating pressure.

Abstract: The invention relates to a buffer storage for a flat web material (2), having at least two roller registers (3, 4) comprising a plurality of freely rotating rollers (11, 12) and displaceable relative to each other at least in one axis direction radial to the axis of the rollers (11, 12), for forming variable partial lengths or loops of the flat web material (2) between the rollers (11, 12) of the roller register, having at least one piston-cylinder arrangement (8), the cylinder chamber (10) thereof being able to be acted upon by a compressible pressure medium, such as compressed air, and acting like a pressure or gas spring between the at least two roller registers (3, 4) for generating a web tension of the flat material (2) guided through the buffer storage, and having a control device for applying a constant or substantially constant operating pressure of the pressure medium to the at least one piston cylinder arrangement (8).