摘要:
In a device for reducing the frictional force between a guiding or carrying element for sheets in a sheet-processing machine, in particular rotary printing machines, guiding and carrying elements acted upon by throttled blowing air include a sheet surface, orifices fluidically connected to a hollow interior, and a throttle disposed in the hollow interior. The elements are to be connected to an air source for blowing air out through the orifices and for generating an air cushion between a sheet and the sheet surface. Each of the orifices is preceded by the throttle with respect to a direction of air from the air source.
摘要:
A guiding device in a machine for processing sheets of printing material includes unthrottled air nozzles for contact-free guidance of the sheets, and throttled air nozzles arranged at locations which are prone to contact by the sheets; and a machine for processing sheets of printing material and a sheet-fed rotary printing machine, respectively, having the guiding device.
摘要:
In a device for guiding sheets in a sheet-fed apparatus, preferably, a rotary printing press, sheet guide elements that are charged with blasted air are disposed at the sheet guide cylinder, and the air blast nozzles include a combination of conventional free jet nozzles and throttled nozzles, which are independently charged with different pressure levels.
摘要:
A sheet transport cylinder in a machine that processes sheets of printing material includes air nozzles for sheet formats of the printing-material sheets. The printing-material sheets are dimensioned from a minimum format up to a maximum format. The sheet transport cylinder is distinguished by the fact that the air nozzles are throttled air nozzles disposed to be matched to the minimum format.
摘要:
A machine for processing sheets, in particular a sheet-fed rotary printing machine, includes a transporting cylinder for transporting the sheets and having air nozzles disposed offset in relation to one another in a direction other than an axis-parallel direction of the transporting cylinder, and having a directing configuration for directing the sheets and having air nozzles, the configuration being assigned to the transporting cylinder. The machine is distinguished in that the air nozzles include throttled air nozzles and unthrottled air nozzles.
摘要:
A smoothing device includes guide surface sections for a flat printing material whose leading edge is pulled in a direction of travel over the guide surface sections. The guide surface sections have openings which communicate with throttling ducts that are pressurized with compressed air during operation. The guide surface sections form a smoothing notch and have air passage openings which communicate with a flow duct. The air passage openings are configured to cause pressure conditions when there is an air throughflow during operation such that the flat printing material forms a bead projecting into the smoothing notch.
摘要:
A sheet-processing machine, particularly a rotary printing press, includes a blast-air supply system and a pneumatic sheet-guiding device connected thereto. The sheet-guiding device has a sheet-guiding surface formed with air passage openings and serves for having the sheets dragged thereover in a sheet travel direction. The air passage openings serve for expelling sheet-carrying air flows during operation. The sheet-guiding device further includes flow ducts for aligning sheet-carrying air flows. The air passage openings in the sheet guiding surface form opening cross-sections of the flow ducts in the form of slots having a length which is many times greater than the width thereof.
摘要:
A machine processing printing-material sheets contains a first sheet transport drum and a second sheet transport drum disposed immediately after the first sheet transport drum in a sheet transport direction. The first sheet transport drum has gripper systems which describe a gripper flight circle during its rotation and a drum profile deviating substantially from a circular shape with outer contour regions running between the gripper systems and set back from the gripper flight circle. The second sheet transport drum has a sheet support surface with pneumatic grooves formed therein. The sheet support surface is composed of a first and second comb segments each with segment prongs. The pneumatic grooves are introduced into the segment prongs of at least one of the comb segments. The pneumatic grooves are preferably introduced both into the segment prongs of the first comb segment and into the segment prongs of the second comb segment.
摘要:
A delivery of a machine for processing flat printing materials, having a sheet guide surface over which the sheets are drawn during operation, with forcible guidance of an edge of the sheets extending in a processing direction, respectively, includes nozzles opening into the sheet guide surface and providing flow therethrough during operation, and a blown air curtain, formed during operation, which extends over the sheet guide surface transversely with respect to the processing direction and is aimed at a target region on the sheet guide surface. The nozzles are arranged on the sheet guide surface in accordance with a first mode and a second mode, the nozzles arranged in accordance with a first of the modes outputting during operation a flow which counteracts a volume flow, from the blown air curtain, which is deflected downline with respect to the processing direction.
摘要:
A device for reducing the noise emissions of a machine for printing flat material, wherein flat material is transportable across an impression cylinder, comprising at least one muffling element disposed across a portion of a transport path of the flat material extending along the impression cylinder, directly behind or downline from a nip, as viewed in the direction of the transport path, and at a spaced distance from the impression cylinder; and a machine including the device.