Research On The Coupled Relationship Between The Mechanical Characteristics And Printing Characteristics Of Printing Press

The vibration of Printing machine impacts printing precision and reliability,vibration will accelerate to be worn and to reduce accuracy, and on the qualityof printing at the same time, to rise the printing speed and production efficiencyhas been the concern of the printing industry, and that put forward of thedynamic design and vibration control. In recent years, printing machinery inChina is leaving behind of abroad, to increase the market competitiveness, it ishigher requirements to the performance and quality indicators of printingmachine. The dynamic behavior of the printing press is a key factor indetermining the quality of printing. Printing machine dynamic characteristic isrefers to the printing presses running at high speed, the system input, thesystem transfer characteristics and the relationships between the systemoutput, it can be divided into mechanical properties and printing properties.Printing machine mechanical properties including the motion precision,dynamic load, vibration response and sound response etc. Printing propertiesmainly the parameters of measure the printing quality, such as print density,overprint precision, dot enlarged rate.In this paper, based on the research of dynamic characteristics of printingpress, analysis of the relationship between the printing machine mechanicalproperties and printing properties, and selection drive, transmission, actuatorsand chain of front lay institution and impression cylinder institution as theresearch object, combining theory with experiment to study mechanicalproperties, combined with printing precision testing data, analysis therelationship between mechanical properties and printing precision.1. Analyzes the law of motions of printing press front lay institution. usingacceleration sensor and B&K acquisition system to collect thevibration signals, and using the Matlab software design high-pass filterto eliminate the low-frequency trend of test signal, than integral to velocity and displacement signals, analysis to obtain its motion cyclechart.2. Modeling the MDOF dynamic model of front lay institution. Accordingto the equivalent substitution principle of concentrate mass method,equivalent the MODF dynamic model to SDOF model, establish thevibration differential equation, divide the vibration into main vibrationand remain vibration which is a key factor impacting the stability ofposition. Use Matlab simulate the main vibration and the remainvibration under different printing speeds, and verify it through theexperiment testing vibration signal characteristics. Analysis theinfluence of sheet feeding accuracy and sheet feeding precisioncaused by front lay vibration, experimental test sheet feedingaccuracy and precision under different printing speed, research toobtain the linear relationship between remain vibration and sheetfeeding precision, the result that when the printing speed is15000S/h,front lay vibration is so large to cause fault of sheet feeding accuracyand precision.3. Analyzes the dynamic incentive types of printing press helical geartransmission system, including the stiffness excitation, error excitationand meshing impact. Built the nonlinear dynamic model ofsingle-stage helical gear transmission and its vibration differentialequations, numerical simulate helical gear meshing stiffnessexcitation, error excitation and internal comprehensive excitations. Setimpression cylinder as actuator, modeling the secondary helical geardynamic system, simulate the impression cylinder radial and axialvibration characteristics, experimental test impression cylinderbearing radial and axial vibration signals, and compared withtheoretical simulation validation to verify its correctness. Testsimpression uniformity and stability data under different printing speed, analysis of the relationship between impression cylinder vibration andimpression stability and uniformity, the result of thet when printingspeed rise from12000S/h to15000S/h, impression uniformity causedby impression cylinder vibration changes slowly, and embossingstability change sharply, when the printing speed is15000S/h,impression uniformity conforms to the requirements of the standard,but impression stability beyond the standard requirements, result inprinting faults.