Abstract: The invention relates to a suction brake for use with a sheet conveyor configured to convey a succession of flat elements in sheet form along a conveying path between a first location and a second location, the suction brake comprising: a hollow body having an interior cavity and a face that defines a plurality of suction apertures that communicate with the interior cavity; an obturator arrangement coupled to the hollow body and moveable with respect to the suction apertures; the obturator arrangement being moveable between an open position, in which the obturator arrangement exposes the suction apertures to a maximum extent, and a restricted position, in which the obturator arrangement occludes the suction apertures to a maximum extent. The obturator may rotate or be linearly translated in moving between the open and restricted positions.

Abstract: The invention relates to a device for gas and/or vacuum distribution (1) for a sheet processing machine (100), the device includes: at least one controllable pilot valve (4; 40), a fixed body (5) including: at least one main gas inlet (7) to be connected to a gas or vacuum source, at least one main gas outlet (8) intended to be connected to at least one suction cup and/or to at least one nozzle, at least a first and a second control gas openings (10, 11), at least one of the openings being connected to the controllable pilot valve (4; 40), at least one housing (9) having a first chamber (9a) communicating with the main gas inlet (7) and outlet (8) and a second chamber (9b) communicating with the first and second control gas openings (10, 11), at least one mobile piston (6) axially movable in the housing (9) by the action of a control gas or vacuum supplied in the second chamber (9b) through the at least one control gas opening (10, 11) connected to the controllable pilot valve (4; 40), the mobile piston (6) b