摘要:
A printing unit is disclosed which incorporates an applicator roller (66) such as anilox roller with bearer surfaces (206) at the ends thereof for positively positioning the applicator roller relative a cylinder, such as a plate cylinder (32) or a blanket cylinder (34). The bearer surfaces (206) on the applicator roller are engaged with the bearer surfaces (202, 204) of the plate or impression cylinder to precisely and consistently position the applicator roller (66) relative the cylinder.
摘要:
A roller assembly (10) is provided which includes an anilox roller (12) mounted with a head (14) for applying a liquid (18) to another surface, such as a delivery, printing plate blanket, or impression cylinder. An end dam (42) is provided at each end of the head (14), which defines a curved seal surface (46) which bears against the bearer surface (58) at each end of the anilox roller (12). The curved seal surface (46) and bearer surface (58) form an end seal for the roller assembly. If desired, lubrication can be provided between the curved seal surface (46) and the bearer surface (58).
摘要:
A vacuum-type sheet transfer apparatus for a rotary printing press includes an air dam device formed by an elongated plate which is supported on the transfer apparatus housing and extends toward the surface of a transfer cylinder or impression cylinder of the press. Spaced apart openings are formed in the plate and have deflectable elastomeric flaps disposed in the openings to allow the cylinder gripper fingers to pass by the plate. An air dam or seal is formed by the plate to redirect the flow of air to urge sheets, including lightweight and heavy weight stock, to follow a preferred transfer path between the impression cylinder and the vacuum transfer apparatus.
摘要:
A method and apparatus for use with a grooved perfecting cylinder in a sheet-fed rotary printing press of the type capable of one sided or two sided sheet printing, the apparatus including a substantially rigid covering having a friction reducing coating thereon and which can be quickly and easily installed and removed over the sheet supporting surface of the perfecting cylinder when the press is operated in the one sided printing mode to permit an anti-marking fabric net to be installed and used over the sheet supporting surface of the perfecting cylinder.
摘要:
A dryer is disclosed in a compact design for interstation use on printing presses, particularly lithographic presses. High velocity air is combined with intense infrared radiation to heat, evaporate and scrub vapor from freshly printed substrates. Air under pressure is provided through passages in a housing which is passed toward and by the infrared lamp in such a way as to cool the lamp and thereafter impact the substrate being dried. A pressure sensing control prevents operation of the lamp without the cooling air. The lamp power circuit is switched off if air pressure is lost. The dryer is mounted in an extractor housing provided with a negative pressure to extract the supplied air after it impacts upon the substrate.
摘要:
A dryer (10, 200) is provided for use in drying freshly printed substrates such as corrugated sheets (14). A plurality of infrared heating lamps (28) are positioned below the travel path (16) of the corrugated sheets (14) and the heat lamps are physically separated from the corrugated sheets by glass panels (108, 110). Provisions are made for cooling the heat lamps by air flow. A plurality of air bars (40) are also provided with pressurized air to discharge air through ports (42) in the upper surfaces thereof for discharge against the corrugated sheet. Air discharged against the corrugated sheet and used to cool the heat lamps is collected and removed by a vacuum pump (48). This pump (48) is also used to remove moisture laden air which has been dislodged from the sheets by the combination of infrared heat and high pressure air.
摘要:
A retractable in-line inking/coating apparatus can apply either spot or overall inking/coating material to a plate and/or a blanket on the first printing unit or on any consecutive printing unit of any rotary offset printing press. The inking/coating apparatus is pivotally mounted within the conventional dampener space of any lithographic printing unit. The aqueous component of the flexographic printing ink or aqueous coating material is evaporated and dried by high velocity, hot air dryers and high performance heat and moisture extractors so that the aqueous or flexographic ink or coating material on a freshly printed or coated sheet is dry and can be dry-trapped on the next printing unit. The inking/coating apparatus includes dual cradles that support first and second applicator rollers so that the inking/coating apparatus can apply a double bump of aqueous/flexographic or UV-curable printing ink or coating material to a plate on the plate cylinder, while simultaneously applying aqueous, flexographic or UV-curable printing ink or coating material to a plate or a blanket on the blanket cylinder, and thereafter onto a sheet as the sheet is transferred through the nip between the blanket cylinder and the impression cylinder. A triple bump is printed or coated on the last printing unit with the aid of an impression cylinder inking/coating unit.
摘要:
An infra-red dryer utilizes high velocity air jets which scrub and break up the moist air layer which clings to the surface of a freshly printed and/or coated sheet. The high velocity air jets are directed through multiple air flow apertures across an array of infra-red lamps onto the freshly printed and/or coated sheets. An extractor exhausts the moisture-laden air from an exposure zone while short wave infra-red radiation heats the ink and/or protective coating. The effective exposure to pressurized air is increased by the air jets which produce a balanced pressure air blanket along the sheet travel path. The moist air layer is displaced from the printed and/or coated sheet and is extracted from the press as the sheet moves through the exposure zone.
摘要:
A vacuum assisted sheet transfer assembly has an array of support bars which support the unprinted side of a freshly printed sheet along a sheet transfer path. The support bars overlie the airflow inlet of a manifold housing, with the longitudinal axis of each support bar extending across the sheet transfer path. The support bars provide smooth surfaces for engaging and supporting the unprinted side of the sheet material as it is pulled along the transfer path while simultaneously limiting the flow of inlet air through elongated inlet apertures. As air is drawn through the inlet apertures, the unprinted side of the sheet is sucked into engagement with the support bars as it moves along the sheet transfer path. The sheet transfer assembly eliminates the need for conventional skeleton wheels and the like. Marking, smearing and smudging are prevented since the printed side of the sheet is not handled or contacted in any way as the sheet is conveyed along the sheet transfer path.
摘要:
A flexible jacket covering is pre-stretched, pre-flattened and pre-cut to predetermined length and width dimensions for attachment onto a transfer cylinder. The flexible jacket covering is marked with alignment stripes and centering marks for faster, simpler and precise attachment of the flexible jacket covering onto the transfer cylinder in an operative position. A predetermined precise amount of movement or looseness of the pre-fabricated flexible jacket covering relative to the transfer cylinder support surface is established in the operative position. Reinforcement strips are stitched onto the gripper, the tail and the operator/gear side edges of the flexible jacket covering for stabilizing the flexible jacket covering and preventing detachment from the transfer cylinder during high speed press operation. At least one side of each reinforcement strip has pressure sensitive adhesive for securing the flexible jacket covering onto the transfer cylinder.