Abstract: In an image area measuring apparatus of the type wherein an image bearing surface of a lithographic printing plate is photographed with a television camera to produce an image signal, the image signal is converted into a digital signal to obtain a measured value and an image area of each one of a plurality of zones of the image bearing surface is determined by an arithmetic operation utilizing the measured value, the image signal is judged by the step of judging the image signal by taking the percentage of dot ratio of a predetermined constant value as a 100% dot ratio when the image bearing surface does not contain a portion corresponding to 100% dot ratio.

Abstract: A unit-to-unit register adjusting apparatus and method for multicolor printing presses includes a plate cylinder, a first plate clamping device on the leading side and a second plate clamping device on the trailing side for jointly clamping a plate on the plate cylinder. Each of the first and second plate clamping devices is disposed in an axial groove in the plate cylinder. The first plate clamping device is adjustably angularly movable by an adjustment bolt in the circumferential direction of the plate cylinder. The second plate clamping device is positionally adjustable by an adjustment bolt in the axial direction of the plate cylinder. By adjusting the first and second plate clamping devices in position on the plate cylinder, the plate can be positionally adjusted circumferentially and axially of the plate cylinder for complete registry with another plate on another plate cylinder.

Abstract: An improved chopper device for use in a folder for folding a signature which has been subjected to parallel folding at a parallel folding device and then conveyed by means of a conveying belt, in a direction perpendicular to the parallel folding direction. The chopper device is provided with an elongated opening having a mouthpiece below the conveying path therefor. An upwardly and downwardly movable chopper blade lowers when the signature is stopper at a predetermined position and forces the signature into the opening. A pair of rollers is provided below the opening in order to grip the signature forced into the opening by the chopper blade nd deliver it to a delivery conveyor. Brushes are provided on both sides of the opening thereabove so as to slidably hold both sides of the signature when the signature is lowered by the rollers through the opening.

Abstract: A inking apparatus includes form rollers brought into rolling contact with vibrating rollers. Each form roller includes a rotatable roller shaft whose axial movement is limited, and a roller body fitted on the roller shaft. Right and left vibration stroke adjusting screws are threadably engaged with male screws at both ends of the roller shaft and are movable in an axial direction of the roller shaft. Compression coil springs are compressed between the right vibration stroke adjusting screw and one of both the ends of the roller body and between the left vibration stroke adjusting screw and the other end of the both ends of the roller body. The compression coil springs define a vibration stroke by positions where the compression coil springs are completely compressed.

Abstract: A sheets aligner is provided with a frame body having vertical surfaces perpendicular to each other, a vertically movable table supported within the frame body, and a plurality of front lays extending along the respective vertical surfaces, thereby to stack on a pallet sheets fed to a sheet feed device for a sheet-fed printing press while aligning the sheet edges by vibration. The sheet aligner is provided with an opening formed in one of the vertical surfaces which is positioned in a direction to the sheet feed direction, the opening being adapted for permitting the pallet to be protruded from the frame body, a pallet stopper for stopping the pallet extruding from inside toward outside of the frame body, and a stop for closing a gap between each lower end of the front lays and the upper surface of the pallet. Thus, this arrangement permits a pallet e.g. for a maximum sized sheet to be used commonly to various sheet sizes.

Abstract: An apparatus for detecting an image area of a thin plate is provided having a housing having a vertical side plate at one side thereof, the vertical side plate having an opening; a door movable to close/open the opening; a holder for holding the thin plate in a location which covers the opening when the door is closed; a camera mounted inside the housing so as to oppose the vertical side plate; the florescent lamps mounted on the inner surfaces of upper and lower plates and side plates of the housing which are perpendicular to the vertical side plate so that illumination directions of the florescent lamps are directed toward the thin plate.

Abstract: In an image area measuring apparatus of the type wherein an image bearing surface of a lithographic printing plate is photographed with a television camera to produce an image signal, the image signal is converted into a digital signal to obtain a measured value and an image area of each one of a plurality of zones of the image bearing surface is determined by an arithmetic operation utilizing the measured value, the image signal is judged by the step of judging the image signal by taking the percentage of dot ratio of a predetermined constant value as a 100% dot ratio when the image bearing surface does not contain a portion corresponding to 100% dot ratio.

Abstract: Double sheet detection method and apparatus of a sheet-fed rotary press, wherein a theoretical reference value is set as an intermediate value between a first theoretical amount of light transmitted through one sheet and a second theoretical amount of light transmitted through two sheets, respectively; the theoretical reference value is subtracted from the first amount of light to obtain a theoretical subtracted value; the theoretical subtracted value is subtracted from an actual amount of light transmitted through one sheet to obtain an actual reference value; and an actual amount of light transmitted through a current sheet is compared with the actual reference value to perform double sheet detection.

Abstract: An intaglio printing machine includes a plate cylinder having a plate thereon, a pattern roller having projections which are in rolling contact with the outer surface of the plate, and an inking unit with a duct roller which is in rolling contact with the pattern roller, wherein the duct roller has substantially the same diameter as that of the pattern roller which includes the projections, and ink holding recesses having different depths corresponding to those of the plate are formed in the outer surface of the duct roller along the circumferential and axial directions thereof.

Abstract: A varnish coater for a printed product is provided, wherein a varnish supply pipe from a varnish tank is open at a position above a bucket-like varnish pan for storing varnish, overflow means connected between the varnish tank and a varnish drain pipe opens at a predetermined varnish level in the varnish pan, and varnish drain port means is formed in a bottom portion of the varnish pan so as to cause the varnish tank to communicate with the varnish drain pipe.

Abstract: In an image area measuring apparatus wherein an image bearing surface of a lithographic printing plate is divided into a plurality of zones and photographed with a television camera to produce analog image signals which are converted into digital signals to obtain a measured value, the image area of each zone is calculated based on the measured value and a quantity of printing ink is determined according to the image area, there is provided a method of processing an image signal including the steps of preparing a first conversion table for 100% dot ratio, and a second conversion table for other percentage of dot ratios, determining the quantity of printing ink from the first conversion table at the time of printing an image having 100% dot ratio, and determining the quantity of the ink from the second conversion table at the time of printing an image having a dot ratio other than 100%.

Abstract: In a varnish coater, a set of a blanket cylinder and a form roller and a set of a pan roller and a metering roller are driven by different drive sources. One-way clutches are arranged between the blanket cylinder and the form roller and between the form roller and a motor as one of the different drive sources, respectively. The form roller is selectively driven by one of the different drive sources through a corresponding one-way clutch. Alternatively, the form roller is driven by one of the drive sources which has a higher rotational speed.

Abstract: In a method and system of measuring an image area, a solid portion corresponding to a portion having a 100% dot ratio in offset printing is formed in a margin of a printing plate, and a blank portion corresponding to a portion having a 0% dot ratio in offset printing is also formed in the margin of the printing plate. Electrical signals obtained from the solid and blank portions are used as reference values for 100% and 0% dot ratios, respectively. Electrical signals obtained from an image bearing portion of the printing plate are converted to image area percentage data in accordance with these reference values irrespective of a nonuniform surface density of the printing plate.

Abstract: In a printing press wherein wetting water is supplied to a platen roller thereof through a group of rollers including a water feed roller immersed in a body of water, an adjusting roller, a transfer roller and a water supply roller in contact with the platen roller, the water supply roller is positioned remote from an inking roller. The transfer roller is rotated at a peripheral speed of 1.5 times to twice of that of the water feed roller.

Abstract: In a varnish coater for a printed product, a blanket cylinder and a form roller are respectively supported by eccentric bearings to throw on/off the blanket cylinder with respect to the form roller and an impression cylinder and throw on/off the form roller with respect to the blanket cylinder, and rollers provided in the eccentric bearings of the form roller are brought by biasing means into tight contact with the cam surfaces of cams pivoted by pivot means so as to simplify adjustment of a contact pressure of the form roller with respect to the blanket cylinder at the throw-on and -off positions of the blanket cylinder.

Abstract: In a paper discharged apparatus for use in a paper folder of the type forming sections of different type, sections of the different type are conveyed in the same direction to the same place by first and second conveyors. The first conveyor has an upper horizontal run and a lower inclined run and has a triangular cross-sectional configuration. The second conveyor has an upper inclined run extending in the direction of the lower run of the first conveyor. A change gear mechanism provided to reverse the direction of running of the first conveyor.

Abstract: In a sheet-fed printing press for the purpose of separating a sheet of paper adhereing to a peripheral surface of an impression cylinder, air is supplied to an interface between the peripheral surface of the impression cylinder and the paper clamping surface of a gripper support, from a source of supply through a pair of arcuate stationary air valves on both ends of the impression cylinder and an axial air passage near the peripheral surface of the impression cylinder.

Abstract: An ink wiping device for an intaglio rotary printing machine comprises a tank for containing a cleaning liquid therein, an ink wiping roller rotatably supported in the tank and having a circumferential surface positioned for rolling contact with a printing plate of the intaglio rotary printing machine, the ink wiping roller having a portion immersible in the cleaning liquid, and a cleaning assembly disposed in the tank and immersible in the cleaning liquid for cleaning the circumferential surface of the ink wiping roller. The cleaning assembly includes at least one brush unit adjustably supported in the tank and having a plurality of rows of bristles having distal ends located in the vicinity of the circumferential surface of the ink wiping roller, and a cleaning sheet of synthetic fibered nonwoven cloth supported on the brush unit and interposed between the circumferential surface of the ink wiping roller and the distal ends of the bristles.

Abstract: In a plate clamping device of a web-fed rotary printing press, a plate cylinder is provided with a longitudinal slot having a narrow opening opened on the peripheral surface of the plate cylinder, a semicircular bottom surface and oppositely inclined surfaces interconnecting side walls of the opening and opposite ends of the semicircular bottom surface. A plate clamping shaft having a flat surface and a slit is loosely inserted in the slot. After inserting one bent end of a printing plate wrapped about the plate cylinder between one inclined surface and the flat surface of the plate clamping shaft and the other bent end into the slit the plate clamping shaft is rotated to tightly fasten the printing plate. Reverse rotation of the plate clamping shaft is prevented by releasable pawls. With this plate clamping device it is possible to tightly fasten the printing plate regardless of its thickness.

Abstract: A sheet is pressed by type characters on a numbering device to form a raised portion on the sheet in a character pattern indicative of a serial number. Simultaneously with printing of an image pattern on the sheet, ink is applied to the raised portion on the sheet to visualize the serial number. With no inking device required for the numbering device, the apparatus is simple in overall arrangement and can be constructed less costly.