Abstract: In a device for changing a sheet stack in a sheet feeder, remaining-stack bars (7A, 7B) of different thicknesses are used to improve operation. Upon combination of a remaining-stack (H) with a H. sheet-stack (S), they are placed in graduations on a pallet (P) and successively pulled from the stack area.

Abstract: In a non-stop stack changing device, remaining-stack bars are pulled from the stack area one by one and out-of-line in relation to each other. To this end, a pull/push drive is provided, which makes it possible to push the remaining-stack bars simultaneously into the grooves of a pallet carrying a sheet stack. Furthermore, the pull/push drive makes it possible to pull the remaining-stack bars in pairs from inside outwards out of the stack area. In addition, the remaining-stack bars can be pulled in a first and second sequence in accordance with this model. An individual motor drive is provided for this purpose, which operates interlockingly on each individual remaining-stack bar.

Abstract: A sheet stack changing device for a sheet processing machine having a main stack lifting mechanism and a remaining-stack carrying device. The remaining-stack carrying device has bars for temporarily holding a remaining stack, a drive mechanism for moving the bars forward into the stack and retracting the bars from the stack in a staggered relation to one another. The remaining-stack carrying device is raised by a lifting mechanism. A pulling mechanism connects the bars with a carrying rail slidably engaged on the remaining-stack carrying device so that the carrying rail slides forward with the bars and retracts independently from the bars.

Abstract: An offset printing device is provided for a rotary printing machine having a plate cylinder carrying a dry flatbed printing plate, the printing device having an improved inking unit which reduces the occurrence and effect of contaminants. In the inking unit, at least one ink application roller, which is frictionally engaged against the plate cylinder during printing, is drivable by at least one positively driven inking roller at a peripheral speed which is different from the peripheral speed of the plate cylinder. In an embodiment, a plurality of ink application rollers contact the plate cylinder and are respectively driven at successively differing peripheral speeds.

Abstract: An offset printing machine having a plate cylinder which carries a printing form and which is operatively connected to an inking unit and a dampening unit is provided. The dampening unit includes a dampening applicator roller which is mounted in contacting relation with the dampening applicator roller. The dampening applicator roller also includes at least one auxiliary roller which is mounted in contacting relation with the dampening applicator roller downstream or after the contact point between the dampening applicator roller and the plate cylinder. The auxiliary roller has a surface with a coating of non-stick material which blocks the transfer of ink and dampening medium to the surface of the auxiliary roller and is axially movable relative to the dampening applicator roller and selectively rotatable at circumferential speeds substantially equal to or different from the circumferential speed of the dampening applicator roller.

Abstract: An apparatus and method is disclosed for the automatically controlled the washing of a part of a printing unit of an offset printing machine as a function of the ink consumed by the unit. The control of at least one washing device, which is assigned to one of the parts of the printing unit, is performed, in particular with respect to the washing frequency, as a function of characteristic values which are derived from functions of the printing unit and/or are generated for controlling these functions. In order to optimize the frequency of the washing operation and/or the type of washing operation, the ink consumption of the printing unit occurring during machine running is determined in accordance with at least one characteristic value of the ink metering, the frequency and/or type of washing operation is then determined from the amount of ink consumption.

Abstract: An offset printing system includes an improved inking unit for applying ink to a rotatable plate cylinder, wherein the inking unit appreciably reduces the production of contaminants. In particular, the inking unit one or more ink application rollers that adjacently contact the plate cylinder. A series of rollers are in ink communication with these application rollers, including at least one inking roller in direct contact with the ink application rollers, and at least one inking roller in indirect inking communication with the ink application rollers. The inking rollers are driven in a positively locking manner and which are drivable at a peripheral speed that differs from the peripheral speed of the plate cylinder, and the inking roller furthest from the plate cylinder is driven with the greatest peripheral speed differential relative to the plate cylinder.

Abstract: In order to improve the sheet removal at the delivery station of a printing press, a blowing device is provided adjacent a side of a delivery stack of printed sheets. The blowing device includes one or more blowing tubes pneumatically coupled to a sheet hold-up device and two front lays of the printing press at the delivery station. When the sheet hold-up devices are extended into the region of the delivery stack and the front lays are swung to a lowered position, the blowing tubes direct a stream of pressurized air into the region of the front edge of the delivery stack. This pressurized air stream, in turn, produces air cushions above and below the sample sheet which to be drawn out, these air cushions separating the sample sheet from the adjacent printed sheets and permitting air free removal even in the case of large printed formats.

Abstract: An undershot inking unit for a printing machine and a method for regulating ink distribution in a printing machine are disclosed. The undershot inking unit comprises an ink fountain roller communicating with an ink fountain, an inking roller, and an intermittent ductor roller for transferring ink from the ink fountain roller to the inking roller. In accordance with the present invention, the ductor roller is thrown onto the ink fountain roller at a rate that is independent of the printing speed of the printing machine, preferably, at a rate that is constant for all printing speeds. The disclosed apparatus and method alleviate the problem of ink fall-off in printing machines.

Abstract: A process and apparatus for automatically changing the stack of sheets in a sheet-fed printing machine is disclosed comprising sheet-carrying surfaces, sheet-separating devices, a pallet, sensors and a control system. The sheet-carrying surfaces act in concert with the sheet-separating devices to create an auxiliary stack separate from the existing stack of printed sheets. In this manner, the existing stack of sheets are removed and the auxiliary stack is deposited on a new stack base as brief and as closely coordinated as possible. The timing of the transition from the sheet-separating devices to the sheet-carrying surfaces is coordinated such that, even in the case of thin printing materials, the stack changing apparatus functions properly during the stack-changing process.

Abstract: A dampening unit for an offset printing machine having a plate cylinder which carries a printing form and which is operatively connected to applicator rollers of an inking unit and a dampening unit. The dampening applicator roller receives a dampening medium feed in front of the contact point with the plate cylinder and at least one roller for receiving dampening medium is in contact with the dampening medium applicator roller downstream of this contact point.

Abstract: A dampening unit for an offset printing machine having a plate cylinder which carries a printing form and which is operatively connected to applicator rollers of an inking unit and of a dampening unit. To improve the print quality appreciably by means of uniform, fault-free feed of dampening medium to the plate cylinder, particularly during the processing of special inks having relatively high metallic pigment components, a dampening applicator roller receives a feed of dampening medium upstream of the contact point with the plate cylinder, and a first auxiliary roller receives dampening medium from the dampening applicator roller and a second auxiliary roller receives printing ink from the dampening applicator roller with the plate cylinder at contact points with the dampening medium applicator roller downstream of this contact point for the dampening applicator roller.

Abstract: An assembly for the metered application of a liquid or pasty medium, to a driven printing cylinder includes a container which is fillable with the medium which provides an outlet opening facing the cylinder. A metering roller is rotatably mounted in the outlet opening and has a portion which protrudes from the outlet opening and can be pressed against the driven cylinder. A metering gap formed between the outer surface of the metering roller and a boundary surface of the outlet opening is adjustable.

Abstract: A pallet construction for use in conjunction with transport apparatus in a sheet-processing system includes spaced grooves adapted to receive automated insertion apparatus. The pallet construction includes webs separated by spaced grooves disposed to receive levelling elements. The levelling elements are movable relative to the webs to provide a relatively planar pallet surface and prevent the deformation of printed sheets. The construction also permits exposure of the grooves as desired.

Abstract: A drive device for reciprocating and rotating a roller such as a dipping roller in a dampening unit in a printing press is disclosed. The drive device includes a first driven unit and a second driven unit. The first driven unit reciprocates the driven roller along its axis whereas the second driven unit rotates the driven roller about that same axis. A coupling is provided in either the first or the second driven unit, or both, to permit the selective deactivation of one or more of the driven units to permit the drive to either rotate the roller without reciprocation, to reciprocate the roller without rotation, or to simultaneously rotate and reciprocate the roller.

Abstract: To improve the throw-on and throw-off movement of the rollers in the roller train of inking or dampening units of a printing machine, an improved and simpler throw-on and throw-off device is provided. For this purpose, intermediate rollers are carried in bearing levers, which enable the intermediate rollers to be thrown off from adjacent distributor rollers. For the simple parallel throw-on of the intermediate rollers, their bearing levers carry cam rollers which are supported on an adjusting rod. The adjusting rod has cam sections which cooperate with the cam rollers, and in response to longitudinal displacement of the adjusting rod, the intermediate rollers are moveable in throw-on and throw-off directions.

Abstract: An undershot inking unit for a printing machine and a method for regulating ink distribution in a printing machine are disclosed. The undershot inking unit comprises an ink fountain roller communicating with an ink fountain, an inking roller, and an intermittent ductor roller for transferring ink from the ink fountain roller to the inking roller. In accordance with the present invention, the ductor roller is thrown onto the ink fountain roller at a rate that is independent of the printing speed of the printing machine, preferably, at a rate that is constant for all printing speeds. The disclosed apparatus and method alleviate the problem of ink fall-off in printing machines.

Abstract: A socket for releasably supporting the journal of a roller in a printing machine is disclosed. In one embodiment, the socket includes: a mounting; an adjusting screw threadably received in the mounting; a locking lever rotatably coupled to the adjusting screw; and a spring element concentrically mounted on the adjusting screw between the locking lever and the free end of the screw such that turning the adjusting screw changes the degree of compression of the spring. The locking lever is coupled to the adjusting screw for movement between locked and unlocked positions. In the locked position, the locking lever is biased into engagement with the roller journal by the bias of the spring to secure the roller within the socket. In the unlocked position, the locking lever is pivoted out of engagement with the journal such that the roller can be easily removed and replaced.

Abstract: A dampening unit for an offset printing machine having an applicator roller including a central section and two oppositely disposed tapered end sections to prevent the transference of excessive amounts of dampening medium to the printing plate is disclosed. The boundaries between each of the end sections and the central section of the applicator roller are located adjacent predetermined regions defined on the plate cylinder to ensure a uniform dampening medium film is produced across the entire format width of the material to be printed.

Abstract: A device for mounting an applicator roller of a dampening unit in a printing machine is disclosed. The device is adapted for rotatably receiving a roller journal of the applicator roller and for fixing that journal relative to the frame part of the printing machine to provide jolt-free operation of the applicator roller. The device is also adapted to provide linear movement of the applicator roller relative to its adjacent plate and dipping cylinders. The device preferably includes adjusting eccentrics mounted one in the other. The adjusting eccentrics are independently adjustable. The eccentricities of the adjusting eccentrics are arranged such that the applicator roller can be thrown-on, thrown-off and set approximately radially both to the plate cylinder and to the dipping roller. As a result of the independent adjustability of the eccentrics, the applicator roller can be optionally thrown-on to the plate cylinder without contacting the dipping roller or vice versa.