摘要:
A printed sheet monitoring assembly utilizes a suction box with a planar lower suction surface to hold a printed sheet to be monitored in a crease-free manner. An area array image sensor is positioned beneath the suction box and is actuated by a trigger device to scan the printed sheet. The sheet grippers on an endless conveying chain are arranged on the chain to be in vertical alignment during scanning of the printed sheet.
摘要:
An offset web-fed rotary printing machine having a plurality of in line printing couples generates torsionsal oscillations. These torsional oscillations are damped by applying a counteracting torsional moment to a free end of drive shaft assembly for the printing couples. The magnitude of the counteracting torsional moment is determined in response to the magnitude of the torsional oscillation moment which is measured by a torque measuring shaft. Damping of the torsional oscillation improves printing quality and press operational speed.
摘要:
Bending movement of a cylinder in a rotary printing press is measured by using a bending rod that is connected to the cylinder journal at one end and to a lateral register adjustment device at its other end. The bending rod is acted on by the bending forces applied to the cylinder and carries strain gauges that detect the bending of the bending rod. A double jointed coupling is used to connect the lateral register adjusting device to the cylinder journal. The bending rod is situated within this double jointed coupling.
摘要:
The draw-roller unit has only one suction roller (20b, 21b) as a draw roller, in which a constantly acting suction effect is effective along that circumferential portion round which the paper web is looped, whilst the remaining circumferential portion experiences no suction effect. The suction roller has a fixed hollow roller core (65) and a roller casing (61) rotatable about this and consisting of plastic-impregnated carbon fibres, with suction ports (62) distributed over its circumference. The roller core (65) is equipped, on its one side, with an axial connection piece (68b) for fastening to the machine stand and for connection to a vacuum source, on its other side with a bearing journal (66) and, on its circumference having passage orifices (70) with two radial partition walls (69) which are arranged at a specific angular distance from one another and which enclose a suction chamber between them. The roller casing is mounted on the bearing journal (66) a conical connecting flange (61b) fastened directly to the rotor shaft of the drive motor and is mounted with its other end on the connection piece (68b), the gaps between roller casing and partition walls (69) being approximately airtight. Instead of a suction roller, a draw roller subjected to compressed air on the outside along the circumferential portion can also be provided, or else the suction-air and compressed-air effects are combined.
摘要:
Damping fluid is applied to a surface of a paper web and is caused to be transported into the web by a gas pressure gradient. The surface of the paper web bearing the damping fluid is subjected to a higher pressure over a large area. The gas pressure gradient can be changed or controlled to vary the rate of damping solution absorption into the paper web.
摘要:
A device for fastening a printing packing to a jacket surface of a printing cylinder uses a clamping carriage that is supported in a cylinder trough. The clamping carriage carries a clamping frame having a clamping face which cooperates with a clamping surface on a lateral trough wall. Clamping of the packing is accomplished without disturbing the position of a gripper device located in the cylinder trough. Transfer of the print material sheets free of register errors is made possible.
摘要:
The wiping device operates with at least one cylinder (3) which receives the ink raised from the printing plates and against which rests a doctor blade (4) which removes the ink from said cylinder (3). In order to clean the doctor blade (4) reliably from ink during the printing operation, there are mounted on the opposite longitudinal edges of said doctor blade (4) wall parts (6) which are U-shaped in the plan view and whose U-limbs (6a) are directed towards one another. Between said U-limbs (6a), an ink slide (8) is moved constantly back and forth on the doctor blade surface by a drive device, the side parts of said ink slide facing the wall parts being adapted to the design of said wall parts. Installed on the back of the doctor blade (4) on each side is an ink pump whose slot-shaped inlet opening (12) extends between the U-limbs of the relevant wall part (6). The ink slide (8) which is moved back and forth acts like a displacement body and pushes the ink passing onto the doctor blade alternately into the inside space bounded by the one or by the other wall part (6), where it is conveyed away by the ink pump and fed to a container.
摘要:
In a device and a method for the regulation of the controlled infeed of web material to a printing machine, a control component of a differential gear placed ahead of a web drive roller is driven by a second continuously adjustable drive by the main drive of the printing machine. Control of the second drive takes place via a servomotor which is connected by a control circuit with a tensioning roller deflectable by the paper web. During control the voltage signal generated by the deflection of the tensioning roller is converted parallel into a voltage signal characterizing the position of the tensioning roller and into a voltage signal weighting the direction of movement. Then these signals are linked into a single output signal and are routed to the servomotor.
摘要:
A bearing bushing supports a bearing assembly of a cylinder journal in a frame bore. The bearing bushing utilizes an inner ring and an outer ring. Both rings are provided with varying wall thickness. A pressure chamber is defined between the two rings in an area away from the resultant of the forces acting on the bushing. A pressure medium can be supplied to this pressure chamber to tightly secure the bearing bushing in the frame bore.
摘要:
Individual printed image elements from an image to be inspected are allotted individual nominal ink density values, as by scanning an ideal printed sheet by a CCD matrix camera. The ideal values are stored in a main memory having segments for average, or grey, values for each image element. A multiplicity of proof images are scanned, and their density values measured and stored for each proof judged acceptable by an inspector. Thereafter, the variations in the acceptable proof density values are stored in the main memory as maximum and minimum acceptable deviations from the initial nominal values for each individual image element to provide a subjective tolerance value for the nominal density values in the main memory.