Abstract: A device for feeding dampening solution in an offset printing unit is presented. The device comprises a plurality of nozzles (22), each of which comprises an orifice (24), wherein each nozzle (22) is configured to eject a solitary droplet of dampening solution of a predetermined volume through said orifice (24) to a roller/cylinder (2, 5) of said offset printing unit, and a control means connected to the plurality of nozzles (22) and programmed to allow a predetermined number of nozzles to eject solitary droplets such that a film of dampening solution is provided across hydrophobic areas and hydrophilic areas of a printing plate of said offset printing unit.

Abstract: A system for supplying dampening fluid to a lithographic press dampening system. A metering roller pair is arranged to form a metering nip such that dampening fluid cannot drain away in a circumferential direction when the rollers stop moving. The metering nip constitutes a reservoir capable of being replenished with dampening fluid so the metering rollers can deliver dampening fluid in a manner that prevents contamination. The system includes a pair of metering rollers having a nip at their junction and a sensor for controlling the supply fountain solution available for delivery to the metering nip.

Abstract: A system for supplying dampening fluid to a lithographic press dampening system. The system prevents dampening fluid starvation at a metering nip located between dampening system rollers, and minimizes contamination of the dampening fluid in the dampening system. A pre-determined distance is maintained between (1) the surface of a roller partially immersed in dampening fluid and (2) a fluid collection pan, so as to remove contaminants from the system. Sensors are used to determine the proper level of dampening fluid within the system to avoid nip starvation.

Abstract: A system for supplying dampening fluid to a lithographic press dampening system. The system prevents dampening fluid starvation at a metering nip located between dampening system rollers, and minimizes contamination of the dampening fluid in the dampening system. A pre-determined distance is maintained between (1) the surface of a roller partially immersed in dampening fluid and (2) several surfaces of a fluid collection pan, so as to move contaminants from a back region of the collection pan to a front region of the collection pan for removal. Sensors are used to determine the proper level of dampening fluid within the collection pan to avoid nip starvation.

Abstract: An internal worm drive has a worm gear and a substantially hollow tubular worm with an outer surface and an inner surface. The inner surface has at least one internal worm thread mating the worm gear. The axis of the worm gear is substantially perpendicular to the longitudinal axis of the tubular worm. Utilizing the tubular worm with the threaded internal surface in conjunction with the mating worm gear is an oscillating roller assembly suitable for use as an ink roller in lithographic presses. The oscillating roller assembly has a shaft, and a bearing unit mounted along the shaft. The worm gear having a plurality of teeth is contained in a slotted space in the bearing unit and the shaft such that the rotational axis of the worm gear is substantially perpendicular to the longitudinal axis of the bearing unit and the shaft. The slotted space has first and second opposite longitudinal ends within the shaft.

Abstract: An internal worm drive has a worm gear and a substantially hollow tubular worm with an outer surface and an inner surface. The inner surface has at least one internal worm thread mating the worm gear. The axis of the worm gear is substantially perpendicular to the longitudinal axis of the tubular worm. Utilizing the tubular worm with the threaded internal surface in conjunction with the mating worm gear is an oscillating roller assembly suitable for use as an ink roller in lithographic presses. The oscillating roller assembly has a shaft, and a bearing unit mounted along the shaft. A worm gear having a plurality of teeth is contained in a slotted space in the bearing unit and the shaft such that the rotational axis of the worm gear is substantially perpendicular to the longitudinal axis of the bearing unit and the shaft. The slotted space has first and second opposite longitudinal ends within the shaft.

Abstract: The invention relates to a method for automatically controlling the water feedrate on a lithographic press which includes a blanket cylinder, a plate cylinder, inking rollers and dampening rollers. The temperature of the fountain solution is regulated so as to be constant. The alcohol concentration is regulated so as to be constant. The ink film thickness on one of the inking rollers is sensed to provide a signal proportional to that variable. The sensing of the ink film thickness on the inking roller is used to determine the water feedrate to the plate cylinder and the rate of water feed is dependent upon the ink film thickness.

Abstract: A multiplicity of web guide rollers in a printing machine incorporate motors therein provided with respective reduction units and each reduction unit is provided on the side of an output shaft with a mechanism such as a clutch, so that the rollers can rotate normally, reversely or idly. When the web guide roller is cleaned, the roller is rotated in a direction opposite to the running direction of the web, whereby the contamination on the surface of the roller is wiped off by the web. Since the rotating directions of the respective rollers are selected by the controller in association with running paths of webs, so that automatic cleaning of the web guide rollers can be effectively performed.

Abstract: An automatic blanket cylinder cleaner having a cleaner fabric adapted to contact the blanket cylinder. A cleaning cloth supply roller provides cloth for the cloth take-up roll. Positioned between these rolls is a water solvent dispensing tube, a solvent dispensing tube and an inflatable and deflatable mechanical loosening means which is adapted to move the cleaning fabric into and out of contact with the blanket cylinder. An air dryer means dries the blanket cylinder after the cleaning of debris. An advancing means advances the cleaning cloth intermittently onto the take-up roller by a control means in contact with the take-up roll which provides for uniform cloth advance during the cleaning cycle. There is a control means providing automatic and manual control.

Abstract: The invention relates to a system for applying dampening fluid to the plate cylinder of printing presses which is particularly adapted to contacting continuous dampening systems. The dampening fluid applying roller is in contact with the rotating plate cylinder and there is a wiping action between the dampening fluid applying roller and the plate cylinder which loosens foreign particles from the plate cylinder so they can be removed. The dampening fluid applying roller rotates at a different speed than the plate cylinder to cause the wiping action. Preferably, the dampening fluid applying roller rotates at a slower speed than the plate cylinder. In another form of the invention an ink receptive roller is driven at the same speed as the dampening or delta roller while in contact with the dampening roller.

Abstract: An ink level control for a printing press is disclosed having an ultrasonic ink level sensor to receive an echo signal representative of the level of the ink in the ink fountain. A control is provided whereby the ink level is maintained at a desired operating level and conditions of excessively low and high ink levels are also detected by the sensor. An echo loss detection network is provided to warn the operator and inhibit ink feeds. The control is designed to prevent overflow of the ink fountain.

Abstract: A non-rotating wedge-shaped ink agitator which reciprocates within an ink fountain along the length of an ink fountain roller. The ink agitator has a substantially flat bottom surface, side surfaces extending upwardly and outwardly from the bottom surface and a top surface which slopes toward the end of the agitator adjacent the ink fountain roller.

Abstract: A system for mixing concentrate and water continuously and automatically including a water supply system and a concentrate system which systems feed into a common conduit to mix the concentrate and water to form a fountain solution. The water supply system has a water motor and is interconnected with valves for controlling the flow of water to and from the water motor. The concentrate system includes a concentrate pump and a concentrate supply valve for controlling the flow of concentrate to and from the concentrate pump.The water motor is interconnected with the concentrate pump to thereby drive the concentrate pump and the stroke of the concentrate pump is variable to permit variations in the concentrate and water mixture.The operation of the water system and the concentrate system is controlled by a pneumatic system which is activated by the water motor.

Abstract: A device for scraping the ink film including lint and debris from an ink fountain roller consisting of a relatively thin, relatively narrow, flexible blade positioned in contact with the surface of the ink fountain roller, the blade being reciprocated along the length of the roller so as to remove ink, lint and debris from the surface of the roller to thereby prevent clogging of the ink metering nip.

Abstract: A system for controlling the viscosity of flexographic and gravure printing ink. The system includes a variable weight hydrometer which monitors the density of circulating printing ink. The hydrometer is in cooperative relationship with a supply of solvent. When the density goes above a predetermined level solvent is fed to the ink until the predetermined level is reached.

Abstract: An automatic blanket cylinder cleaner having a cleaner fabric adapted to contact the blanket cylinder. A cleaning cloth supply roller provides cloth for the cloth take-up roll. Positioned between these rolls is a water solvent dispensing tube, a solvent dispensing tube and an inflatable and deflatable mechanical loosening means which is adapted to move the cleaning fabric into and out of contact with the blanket cylinder. An air dryer means dries the blanket cylinder after the cleaning of debris. An advancing means advances the cleaning cloth intermittently onto the take-up roller by a control means in contact with the take-up roll which provides for uniform cloth advance during the cleaning cycle. There is a control means providing automatic and manual control.

Abstract: A rectilinear positioning mechanism for precisely controlling the rectilinear position of an output member. The rectilinear positioning mechanism of this invention includes a relatively thin beam which is flexible particularly along its longitudinal length. The flexible beam is fixed against movement at one end while the other end is free to move in the longitudinal direction.There is an input mechanism located between the ends of the flexible beam for deflecting the center of the flexible beam in a controlled, precise manner to thereby change the position of the free end of the beam.The mechanism has utility as a positioning means generally and for positioning the ends of segments of a metering blade with respect to the ink fountain roller in an ink fountain assembly.