摘要:
The invention is a method for retaining an ink profile established during ink infeed, for printing in an inking unit of a printing press containing a drive for the inking unit, an ink dosing device, and a roller group in the inking unit having oscillating rollers and transfer rollers, by delaying printing after ink infeed by interrupting the drive to the inking unit for a time period between the end of ink infeed and delayed printing; and to apparatus for effectuating such drive interruption.
摘要:
A method for supplying printing ink to an ink tray of a printing press having a plurality of ink zones throughout the width of the printing to be done, an ink tray and an ink ball extending over the width and having a longitudinal axis along the printing to be done and being substantially coextensive with the ink tray, an ink supplying means at an ink supplying location, and an ink spatula for distribution of ink within the ink tray, the method comprising determining the ink requirement data for the various ink zones, inputting the ink requirement data into a computer for producing a plurality of control signals for regulating the supplied ink in supply cycles to the ink zones, supplying ink to each ink zone at the location of each ink zone, shifting the supplied ink by the ink spatula to a zone in need of ink, with priority being given during the supply cycle to the ink requiring ink zone that is most remote from the ink supplying location, the amount of ink being supplied during the supply cycle being sufficient to prevent the amount of ink from falling to below a predetermined minimum ink level in each ink zone.
摘要:
The invention relates to a method for ink supply to ink trays in printing presses, whereby the printing press has for ink supply an ink tray, which is adjoined with an in ball cooperating with ink dosing elements. Task of the invention is to provide a method and an apparatus for zonal ink dosage according to the ink requirements and an extensive residue-free emptied ink tray at job end or job change. The task is solved according the invention by stopping the ink supply before the end of the printing job. This moment is determined so, that a minimum amount of ink sufficient for the to be processed product volume remains in the ink tray at the pre-determined job end and the ink is shifted from ink zones or ink zone groups with lesser ink consumption to ink zones or ink zone groups with momentarily higher ink consumption for processing of the remaining printing job.
摘要:
Ink distribution to the transfer roller of a printing machine is rapidly influenced. The ink duct roller is driven at a maximum speed and the ink distribution roller is caused to rotate at the ink duct roller speed. The ink vibrator roller is brought ink continuous engagement with these two rollers and is brought out of contact with its oscillating drive mechanism. The ink fountain is closed and excess ink is conveyed back to it. The original speeds of the ink duct roller and the ink distribution roller are re-established and the oscillating drive of the vibrator roller is resumed.
摘要:
The invention relates to a device for supplying a shingled or overlapping sheet stream from a stack of sheets of a sheet feeder to a feed table of a sheet-processing machine with a belt table. The belt table is provided with at least one revolvingly driven suction belt, which is in operative connection with at least two suction boxes that can be acted upon by negative pressure. The invention can include a device for taking hold of the sheets. The invention also relates to altering a device so that, independently of the material to be processed, a last sheet of a sheet stream can be easily aligned. This objective is accomplished as follows: after the last sheet is detected and its front edge has been placed against the front guide stops, the operation of the suction belt is stopped.
摘要:
A method for cleaning cylinders of rotary printing presses simplifies the changing of cleaning cloths. The exact effective length of the cleaning cloth available for the cleaning process can also be determined in the course of changing the cleaning cloth. A fresh supply roller carrying a fresh cleaning cloth 5 is inserted into the second cleaning cloth depot for replacing the soiled supply roll. The start of the cleaning cloth on the fresh supply roller is fixed in place on a spindle located in the first cleaning cloth depot and the fresh cleaning cloth is wound onto the spindle to form a fresh supply roll while determining the length of cloth wound on the spindle. The end of the fresh cleaning cloth remains in the second cleaning cloth depot and now forms the receiving roll during the cleaning process.
摘要:
A dual motor drive system particularly adapted for the drive of long printing presses provides uncoupled control of both the voltage and current provided to the motors. A current divider proportions the current provided to a main and secondary motor in accordance with a chosen ratio to maintain speed and torque in accordance with press requirements.
摘要:
The drive for the multicolor rotary press has a main drive shaft, a connected synchronized gear train which extends substantially parallel to the drive shaft and which connects the press mechanisms with each other and a torsion spring-rod which couples the main drive shaft and the synchronized gear train. For coupling the main drive shaft with the synchronized gear train the torsion spring-rod is mounted on an axle journal of a press cylinder. To provide a drive for operation of the press at several different operating speeds a force-locking or frictionally-engaging coupling clutch is mounted on bevel gear shafts located between the press cylinder of one press mechanism drivable by a torsion spring-rod and another press cylinder of an adjacent press mechanism carrying a transversely moving linkage. One of the bevel gear shafts is driven by another gear coupled with the main drive shaft, so that, when the clutch is engaged, particularly at start-up and low speed operation, the press cylinders are driven without the torsion spring-rod, but when the clutch is disengaged, the press cylinders are driven through the torsion spring-rod thus damping oscillations due to gear teeth tolerances.
摘要:
An ink metering method for an inking mechanism of a rotary printing machine having an ink fountain, a doctor roller, a separate electric motor for driving the doctor roller and a low speed of rotation relative to the printing machine, includes the selection of a rate at which the electric motor imparts to the doctor roller discrete angular motions; and selecting by a second selector switch the magnitude of the angular motions. A circuit arrangement for carrying out the method includes a time selection unit which delivers at its output a series of pulses at a desired rate; an increment evaluation unit which receives at its input a number of pulses corresponding to the magnitude of the angular motion performed by the electric motor and compares the momentary number with a preset desired number corresponding to a desired magnitude of the angle of rotation.
摘要:
A printing press is provided with a safety device mounted in the vicinity of a gap formed between two counter printing rollers for preventing the gap from intrusion by foreign elements, such as a mop or the hand of an operator. The device includes a four-link transmission unit operatively interconnected between pivotable guard plates and a cam switch adapted to actuate an end switch of the printing press to shut the latter off. The guard plates are swung away from the rollers so that the gap is enlarged.