Papers by Keyword: Printing Press

Abstract: This paper outlines a design process for the bolted joints of the drive train of sheet-fed offset printing presses incorporating statistical data and methods. Sheet-fed offset printing presses are driven by a continuous geared drive train along the length of the press. The bolted joints of the drive train connecting the gears to the cylinders of the press are subjected to high loads, especially during emergency stops. A nonlinear mechanical model of a printing press implemented in Matlab/Simulink is presented which is used to calculate the occurring loads. Measurements of linear and nonlinear system response are presented to support the quality of the mechanical model. The bolted joints between the main drive train gears and cylinders are designed according to current standards. Statistical information based on experimental data is considered during the application of the standardized method. Using the Monte Carlo technique, a more exact description of the joint’s strength is made possible. In this way, the maximum tolerable load for the screw connection is 16% higher than the same result from a standard worst-case calculation.

Abstract: The precondition of improve the printing press velocity is to maintain the minimum vibration of infeed unit within the range of press speed. Taking advantage of the equivalent relation between the formula of infinitesimal energy and the classic beam theory, the vibration of convey paper belt can be converted into the problem of the beam be stretched and be compressed, and then we utilize the finite element simulation technology to conduct model analysis for the convey paper belt. When the numerical of the belt speed gain ,both the vibration and shape distortion reach the maximum, as well as speed of the infeed unit will be influenced most.

Abstract: Printing machinery’s reliability is one of the most important index parameter and good dynamic characteristics are essential for high speed printing press. The dynamic characteristic is predictable for printing machine with dynamic design. With the complexity of printing technique and printing machine, information, such as load on components is lack, leading to the difficulty of dynamic model solving and further more the dynamic parameters needs to be verified. Firstly, according to the dynamic design method, a dynamic design process based on measuring information for printing machine was put forward. Secondly, on the basis of principle and structure analysis to typical printing machine, dynamic characteristics measurement item and method was determined. With a wallboard of a two-color offset press acting as an example, the utilizing method was illustrated through dynamic modeling, theoretical model analysis, experiment model analysis based on vibration measurement and comparing the theoretical and experimental results. Finally, a Dynamic Design Assistant Platform based Vibration Measurement for Printing Machine was developed and had been used in 10 kinds of printing machine measurement and analysis. The conclusion shows that the tolerance of the theoretical model analysis results and experiment results is allowed. A new approach for new printing machine design and optimal design for existed printing machine is given.

Abstract: Printing cylinder driven by helical gear is the basic requirements of the modern printing press. Helical gear transmission necessarily produces component force in axial. It brings about a small displacement in axial to the cylinder, that is, axial bounce. The axial placement is too small or too large during the printing process, which both will have harmful effects on printed matter. At the same time, the axial playing of the cylinder is one of the important performance standards to determine printing press. The modern high-speed printing press has a higher requirement on mechanic properties and axial bounce. We tested on the cylinders of press and analyzed on the placement of the cylinders in order to effectively master and control the displacement in axial in the case of the printing press running with high-speed. We chose a four-color offset press as the test objects and reasonably selected measurement points on the cylinder shaft end face. We collected vibration signals of the blanket cylinders, impress cylinders and transfer cylinders. Then obtain the placement in axial of the cylinders with quadrature method. Analysis shows that the higher the printing speed, the larger the placement of the same type cylinder in axial is, which shows that the placement of the cylinders in axial has something to do with the printing speed. At the same speed, the blanket cylinder have a larger placement in axial than impress cylinder and transfer cylinder. Which shows that the placement of the cylinders in axial has connection to the cylinder assembly structure. Test data accord well with the actual structure and assembling condition, which can be considered as the theoretical basis to control the placement of cylinder in axial.

Abstract: In order to study the performance of speed feeding, an experimental feeding device was designed. The main design considerations are: Easy to adjust parameters, separate movement control of each device structure, and distribution control for the suction and blowing in the feeding device. The control system is developed on windows PC system. KPCI-884 motion control card is adopted as the I/O interface for the motion control, feeding movement is driven by servo motors, a high-speed solenoid valve is used for gas distribution and system UI is developed in VC++ language. A test run indicates that the system is in good operational condition. In the research, the synchronous control of multiple servo motors in a open-loop state is achieved as well as the detection and control of peripheral signals.

Abstract: Aiming at the reuse of design knowledge, this paper proposes knowledge reuse technology for product design of printing press which is based on rule and case. An integrated software package with SQL Server which is Database Management System (DBMS) and VisualC++6.0 which is a kind of development tools has been developed. This software may be embedded in the environment of Solidworks to assist the designer to index correlative design knowledge and develop new product of printing press after modification.