Heidelberger Druckmaschinen Ag

Heiner Luxem

Gerhard Pollich

Andreas Fricke

Erich Michael Zahn

Michael Nubel

Norbert Thunker

Lothar Stadler

Maren Greive

Rudi Hofstetter

A method for eliminating rhythmic register errors in sheet-fed rotary printing machines, the sheets therein being transported by an impression cylinder of double size having two gripper arrangements, includes bringing front lays, which have been provided for orienting the sheets at a feed table, out of an end position outside a conveying plane of the sheets and into a first orientation position on the feed table, then bringing the front lays back into the end position, and thereafter bringing the front lays into a second orientation position on the feed table; and a device for performing the method.

Method and device for eliminating rhythmic register errors in sheet-fed rotary printing machines

A device for conveying a stream, in particular an imbricated or shingled stream, of sheets to a sheet processing machine, having a conveyor table formed with suction holes, and at least one endless transport belt formed with suction holes extending therethrough and being revolvingly drivable around the conveyor table, includes at least one suction box disposed under the conveyor table and having vacuum applied thereto, the one suction box being connected, via the suction openings formed in the conveyor table, to an underside of the transport belt, the one suction box being individually assigned to the respective one endless transport belt and being formed with a single suction chamber, the one suction box having at least two suction connections spaced apart from one another, as viewed in a sheet transport direction.

Device for conveying a shingled or imbricated stream of sheets

A device for aligning sheets on a feeding table of a sheetfed printing press having at least one swivelably mounted top lay and at least one swivelably mounted front lay, and a control device for cyclically moving the at least one front lay and the at least one top lay includes a control device for the at least one top lay operative independently of the control device for cyclically moving the at least one front lay and the at least one top lay, the at least one top lay being disposed so as to be vertically movable and being constructed wider than the at least one front lay, and the at least one front lay being laterally encompassed by the at least one top lay.

Device for aligning on a feeding table of a sheet-fed printing press

Gripper control for a cyclically rockingly driven pregripper for single-sheet feeding in a sheet-fed printing press, the pregripper being disposed at a free end of a rocker lever, which is swivelable about a rocker shaft fixed to a frame of the printing press, and having at least one sheet gripper forcibly movable by cams about an articulated shaft disposed parallel to the rocker shaft, for closing and opening the sheet gripper when the sheet is taken over and transferred, respectively, one of the cams being revolvable a single revolution, and another of the cams being disposed on a locally stationarily swivelable roller lever carrying a cam roller engaging with the one cam, the other cam being swivelable cyclically in the position thereof, the position of the cams determining the closing time and opening time of the gripper, includes an indexing mechanism for fixing the other cam on the locally stationarily swivelable roller lever, the other cam having a first gripper-closing cam region and a first gripper-opening cam region, the first gripper-closing cam region having a second gripper-opening cam region, the one cam revolvable a single revolution having a second gripper-closing cam region operatively associated with the second gripper-opening cam region for compensation.

Gripper control for a cyclically rockingly driven pregripper for

Device for register correction and for compensating for distorted sheets in a pregripper of a feeder for a sheet-fed rotary printing press has a frame-fixed brace disposed on a pregripper shaft and located approximately centrally between end supports on a gripper bar, the gripper bar being supported rigid against torsion at opposite ends thereof on the pregripper shaft and being capable of executing swivelling movements in a sheet-feeding direction and in a direction opposite thereto, the frame-fixed brace serving for elastically bending the gripper bar in the sheet-feeding direction before the sheet is gripped by sheet grippers which are disposed side by side on the gripper bar and are swivellable about an axis of the pregripper shaft, the brace including a cam roller by which it runs onto an adjustable cam having a frame-fixed support, and an articulated joint with an eccentric element having a lever arm connected thereto for carrying the cam roller spaced from a center of the eccentric element.

Device for register correction and for compensating for distorted sheets

A device for uniting a residue sheet pile and a main sheet pile into an aggregate sheet pile wherein a lowermost sheet of the residue sheet pile rests upon and uppermost sheet of the main sheet pile includes a displacement device having a drive; and a rake displaceable by the displacement device along a displacement path in a pile slide-in direction from a first to a second position and from the second to the first position in a direction opposite to the slide-in direction. The residue sheet pile is seated with its undermost sheet on the rake in the second position thereof, and the main sheet pile is in engagement with the rake from below with the uppermost sheet thereof, in one phase of the pile uniting process. The rake has traversed the displacement path in the direction from the second to the first position thereof, in a final phase of the pile uniting process. The rake is formed of lattice bars having respective free ends extending in the slide-in-direction, and the free bar ends have a cross-section reducing in height substantially constantly in the slide-in direction; the reduction in cross section of the free ends of the lattice bars being such that when the residue sheet pile becomes seated on the lattice bars, a lateral face of the residue sheet pile extending in the slide-in direction is simultaneously lowered onto a reduced cross section of the lattice bars.

Device for uniting a residue sheet pile and a main sheet pile

A measurement device for detecting the presence of a sheet is disclosed. A paper sheet processing machine has front lays with stop surfaces at which the leading edges of paper sheets are aligned. The paper sheets are accelerated by pre-grippers to a speed sufficient for transferring the paper sheets to a paper sheet processing unit, such as a transfer drum in a sheet-fed rotary offset printing machine. The measurement device comprises upper and lower sensor members between which a gap is defined. The leading edges of sheets which are aligned at the front lays are disposed within the gap. The upper and lower sensor members forming upper and lower boundaries, respectively, of a scanning region which is defined vertically relative to the plane of the paper sheet. Paper sheets which cross the scanning region between the sensor members and which are aligned along the stop surfaces of the front lays are detected. A method and a corresponding pre-gripper assembly are disclosed as well.

Device and method for detecting and gripping sheets

A device for uniting residual sheet pile and a main sheet pile into an aggregate pile, wherein a lowermost sheet of the residual sheet pile rests on an uppermost sheet of the main sheet pile, includes a pile-carrying plate having a horizontally oriented upper side whereon the residual sheet pile rests with its lowermost sheet prior to a performance of a pile uniting process, the pile-carrying plate having mutually parallel grooves formed on the upper side thereof, an auxiliary carrying device for temporarily carrying the residual sheet pile including an assembly of horizontally disposed and mutually parallel lattice bars fitting into respective cross sections of the grooves formed in said pile-carrying plate and combined into a rake, guide rails whereon said rake is mounted so as to be displaceable in the longitudinal direction of the lattice bars, a stop rail extending transversely to and being displaceable in the longitudinal direction of the lattice bars, the stop rail being formed with penetrations through which the lattice bars are capable of passing through the stop rail, an auxiliary carrying device having a frame, the guide rails and the stop rail being fixed components of the frame, the frame being mounted within the auxiliary carrying device so as to be displaceable in the longitudinal direction of the lattice bars and in a horizontal plane transverse to the longitudinal direction of the lattice bars.

Device for uniting a residual pile of sheets and a main pile of sheets

A process and an apparatus for prestacking in a sheet feeder of a rotary printing press provided with lateral stack stops, which can be adjusted to the format of the sheet to be printed, the printing press also having an automatic lateral stacking orientation and a stack raising apparatus, which are designed so that they make possible an easy manual prestacking in the sheet feeder by the operator.

Process and apparatus for prestacking in a sheet feeder of rotary

A sheet transfer device for a printing machine for taking over sheets which have been aligned at front lays and for transferring the sheets to a sheet-guiding drum includes a pregripper device swivellable between a sheet takeover and a sheet transfer position. Gripper pads are carried by the pregripper device, and a gripper shaft is swivel-mounted in the pregripper device and carries gripper fingers which are associated with the gripper pads. Also provided are a device for connecting the gripper shaft and the gripper fingers so that swivelling movements of the gripper shaft are transmitted to the gripper fingers, and a swivel device for swivelling the gripper shaft about a longitudinal axis thereof. A cam segment has a control surface for controlling the swivel device, and is adjustable so that a gap, formed between the gripper fingers and the gripper pads in the takeover position of the pregripper device and existing until alignment of the sheet at the front lays is terminated, is settable in accordance with the thickness of the sheets. The gap is so defined that the gripper fingers form top lays for a respective leading sheet edge. A control shaft is provided for adjusting the cam segment, the control shaft extending parallel to generatrices of the control surfaces and being arranged so as to be adjustable parallel to itself.

Growing community of inventors

Wilhelmsfeld, Germany

Heiner Luxem