*there are publications in scientific journals
MAGAZINE UPAKOVKA (PACKAGING) # 6-2023
DIE-CUTTING PRESS EQUIPMENT: PROSPECTS FOR REPLACING THE MONOBLOCK DESIGN OF THE PRESSURE PLATE WITH A SECTIONAL ONE
I.I. Rehei, D.Sc., V.V. Vlakh, Ph.D., Yu.Yu. Mykhailiv
The article states that high-tech modern equipment is used to increase the production of cardboard packaging. The critical function of die-cutting presses, which are heavily loaded due to the cyclic overcoming of significant technological resistances, is emphasized. It is proposed to minimize the force load in the press by step-by-step die-cutting of the cardboard blank with separate sections of the pressure plate with an eccentric drive. It was established that the angular displacement of the eccentrics in the sections of the pressure plate depends on the thickness of the cardboard and the eccentricity, and the implementation of the sectional construction of the pressure plate solves the important task of reducing the metal consumption of the die-cutting equipment.
Keywords: cardboard packaging, die-cutting press, technological resistance, step-by-step die-cutting, pressure plate section, eccentric drive.
PRINTING AND PUBLISHING * 2023 / 1 (85)
COMPARATIVE ANALYSIS OF THE KINEMATIC PARAMETERS OF THE WEDGING DRIVE MECHANISMS OF THE DIE-CUTTING PRESSES USING THE SOLIDWORKS SOFTWARE
V. V. Vlakh
Diecutting presses are essential equipment components for producing cardboard packaging blanks. The efficiency and quality of their production depend on the design and operation of the drive mechanism of the pressure plate in the diecutting presses. This study presents a kinematic analysis of wedging mechanisms in the drive of the pressure plate using the SolidWorks software. To design a 3D model of the mechanism, calculations of the geometric parameters of the mechanisms are performed based on the dimensional parameters of the punching press. The graphical representation of the obtained data during the modeling of the studied mechanisms in SolidWorks Motion is provided. Based on the research on changes in the values of kinematic characteristics, a comparative analysis of the operation of the drive mechanisms of the pressure plate is conducted.
Keywords: diecutting press, cardboard blank, pressure plate drive mechanism, doublecrank wedging mechanism, CAD/CAE modeling, kinematic analysis.
THE DRIVE OF THE PRESSURE PLATE IN THE STAMPING PRESS (AN INNOVATIVE TECHNICIAN DESIGN SEARCH)
I. I. Rehei, Doctor of Sciences, V. V. Vlakh, Ph.D.
The article states that in the technological process of manufacturing cardboard packages, an important operation is the die-cutting of their blanks on special presses. The machines are equipped with wedging lever mechanisms to ensure vertical movement of the pressure plate. The task of obtaining high-quality sweeps with relief embossing is singled out. The new scheme of the lever wedging mechanism for extending the duration of contact of the form tools with the cardboard is proposed and synthesized, in which a driven crank with a gear drive is attached to the existing one. The relative duration of contact of punching tools with cardboard blanks of different thicknesses was investigated, and a comparative analysis was performed.
Keywords: technological process, lever wedging mechanism, die-cutting form, sweep, relief embossing, driven crank.
PRINTING AND PUBLISHING * 2022 / 2 (84)
COMPLEX ANALYSIS OF THE PRESSURE PLATE DRIVE MECHANISMS FUNCTIONING IN DIE-CUTTING PRESSES
I. I. Rehei, V. V. Vlakh, O. B. Knysh, O. I. Mlynko
In manufacturing cardboard packaging, the main technological operation is stamping, which forms the configuration of the cardboard sweep. The most common is the equipment in which flat punching is implemented. In such presses, the main mechanism is the drive mechanism of the movable plate, which moves parallel to the statically fixed stationary plate. This work has researched publications and inventions for improving the die-cutting press mechanism. Here are the results of world scientists who have proposed mechanisms that eliminate certain shortcomings of existing die-cutting press mechanisms but also have their shortcomings. The article’s authors have made a kinematic analysis of already existing mechanisms (BOBST, Heidelberg) and proposed a comparative characteristic.
According to the derived equations, the relative parameters of the pressure plate (displacement, speed, and acceleration) are calculated. The curves of the pressure plates’ relative movement nature for the eccentric-sliding and eccentric mechanisms are similar. It shows that the pressure plate moves faster than the stationary one and stays longer in the technological operation of punching sweeps in these mechanisms. In the wedging mechanism, the movements of the right and left sides of the pressure plate are not synchronized, which causes its oscillating motion. The pressure plate moves more smoothly to the extreme position in the two-slider mechanism as in the wedge mechanism.
Based on the pressure plate relative speed analysis results, its most prominent peaks are characteristic of the two-slider and wedging mechanisms. Slow plate acceleration is detected in the two-slider mechanism and faster in the eccentric-slider mechanism. In addition, the graphs of changes in the relative speed of the pressure plate in the eccentric-slider and eccentric mechanisms are similar.
The wedging mechanism provides the maximum value of the relative acceleration of the pressure plate at the moment of contact with the stamping die. In this case, the pressure plate mass inertia force is maximally used to die-cut the sweeps to overcome the technological resistance. In eccentric and eccentric-slider mechanisms, the start of the cycle is accompanied by peak values of the relative acceleration of the pressure plate, which requires energy costs to overcome the inertial load at this stage. The two-slider mechanism provides an almost constant relative acceleration of the pressure plate during the rotation angle of the main shaft in the range of 165° – 195° during the phase of punching the sweeps.
Because of the work performed, it can be stated that there is an urgent task of improving the drive mechanism of the flat die-cutting machine in terms of energy efficiency, productivity, quality of punching, and ease of manufacture.
Keywords: pressure plate, punching press, cardboard sweeper, cardboard packaging, technological effort, wedging mechanism.
ACADEMIC JOURNAL OF MANUFACTURING ENGINEERING, VOL.21, ISSUE 3/2023
COMBINED DOUBLE CRANK WEDGING DRIVE MECHANISMS OF THE PRESS PLATE USED IN DIE-CUTTING PRESS: SYNTHESIS, KINEMATIC AND FUNCTIONAL
Ivan REHEI, Vitalii VLAKH, Oleh KNYSH, Rostyslav KNYSH and Oksana MLYNKO
The production of cardboard packaging begins with the die-cutting of sweeps on special presses equipped with wedging lever mechanisms for driving the press plate, ensuring the forced interaction of tools of a flat die-cutting stamp with cardboard cuttings. It set a goal to provide the needed duration of contact of the technological tools of the die-cutting stamp for creasing the bending lines and forming relief images. It is offered to use additionally driven cranks in the wedging drive mechanisms of the press plate. There are examined schemes of combined wedging drive mechanisms of the press plate: existing mechanism, double-crank with upper and lower initial positions of the driven crank. Their relative geometrical parameters were taken to synthesize and calculate the mechanisms under study. Based on the results of analytical studies, the perspective of their application was outlined.
KEYWORDS: die-cutting press, wedging mechanism, driven crank, press plate, invariant
ACADEMIC JOURNAL OF MANUFACTURING ENGINEERING, VOL.21, ISSUE 1/2023
ANALYTICAL INTERPRETATION OF EXPERIMENTAL RESEARCH OF CARDBOARD CUTTING IN DIE-CUTTING PRESS
Oleh KNYSH, Ivan REHEІ, Vitalii VLAKH, Oksana MLYNKO, Serhij TERNYTSKYI
The paper reports analytical research on torques during cardboard cutting in the die-cutting press with eccentrics in the drive of the movable pressure plate. An analysis of the mechanisms of the pressure plate drive in die-cutting presses and the mechanics of cardboard destruction by a cutting tool was carried out. A method of analytical research of torque from forces on the drive shaft of the eccentric mechanism of the pressure plate drive has been developed. The paper shows changes in the torque value on the drive shaft during the kinematic and estimation of their quantitative values compared to the designed experimental device. The torques caused by technological efforts are decisive in the total torque on the drive shaft value. A comparative analysis of the experimental dependence and analytical dependence of the total torque on the drive shaft shows that the torque change on the drive shaft of the press is similar in both cases.
KEYWORDS: cardboard, die-cutting press, cutting, pressure plate, eccentric
SCIENTIFIC PAPERS * 2018 / 1 (56)
COMBINED DRIVE MECHANISM OF A PRESS PLATE USED IN FLAT
DIE-CUTTING PRESS (EXPERIMENTAL EVALUATION OF LOADS)
S. V. Ternytskyi, N. M. Kandiak, V. V. Vlakh, O. O. Palamar
In the article, the research of loads (torques) has been carried out that arise on the mechanism drive shaft of the press plate in a flat die-cutting press during the cardboard consumer packing cutting process. It makes obtaining reliable and systematic torque values possible, depending on the cardboard’s thickness, type, and direction of fiber disposition.
An experimental test device of the combined mechanism of the press plate has been developed and designed with the possibility of changing and controlling the speed of the drive shaft. In the developed experimental apparatus, a scheme of a flat die-cutting press with a lower movable press plate has been realized. A combined mechanism provides the drive of the press plate.
The strain gauge is obtaining reliable data. It has been revealed that the thickness of the cardboard does not affect the nature of the change curve. It only affects the maximum values of torque. For each thickness of the cardboard, there is a certain torque value. In the article, the influence of the cardboard thickness on the torque value of the mechanism’s drive shaft has been analyzed, including the influence of the direction of fiber disposition of cardboard concerning the cutting line. It has been established that with the doubled increase in cardboard thickness, the magnitude of the torque increases by 2.1 times during cutting along the fibers and by 1.65 times across the fibers.
It has been confirmed that the press plate’s combined drive mechanism ensures the plates’ parallelism during the working cycle, which provides the stability of the machine’s working process and increases product quality.
Keywords: packaging, experimental press, die-cutting, ejector pillows, crank-cross head mechanism, cardboard, torque, load.
PRINTING AND PUBLISHING * 2018 / 1 (75)
EXPERIMENTAL EVALUATION OF THE SPEED MODE EFFECT
ON POWER LOADS OF THE COMBINED MECHANISM
OF THE PRESS PLATE DRIVE AT CARDBOARD DIE-CUTTING
S. V. Ternytskyi, N. M. Kandiak, V. V. Vlakh
A laboratory test device for experimental research of a combined mechanism of the press plate drive in a flat die-cutting press has been developed and designed. The torque value on the drive shaft of the mechanism has been experimentally determined while cutting cardboard samples of different thicknesses.
The article is focused on the research of the torques on the drive shaft of the combined mechanism of the press plate that arise in the process of die-cutting the cardboard involutes with different thicknesses at different values of the speed of the laboratory test device.
During the experimental research, a high-precision contactless tachometer was used to study angular velocity on the drive shaft and control its value. The strain gauge sensors have been used to measure the torque values on the drive shaft of the combined mechanism of the press plate.
It has been revealed that increasing the crankshaft, which increases the cutting speed, causes a decrease in torque on the drive shaft of the mechanism. The efficiency of the modernization of the press plate drive mechanism in flat die-cutting presses has been confirmed by applying the suggested mechanism, given the possibility of operating at various speeds.
It has been revealed that an increase in the rotation speed of the drive shaft by four times from 40 rpm to 160 rpm leads to a decrease in the torque values on the drive shaft of the mechanism for cardboard with a thickness of 0.5 mm and 0.7 mm by 13%, and for thin cardboard with a thickness of 0.3 mm — by 30%.
The results of experimental studies have proved the practicality of improving the flat die-cutting presses by the lower press plate drive mechanism.
Keywords: packaging, die-cutting press, cutting, ejector pillow, crank-cross head mechanism, cardboard, torque, rotation frequency, tachometer.
Technological Complexes #1 (13), 2016
AUTOMATED SYNTHESIS OF MECHANISM OF PRESS OF DIE-CUTTING MACHINE
Vlakh V., Pasika V.
The die-cutting process consists of a whole complex of operations that help to determine the shape, geometric dimensions, and design of cardboard packaging. This process occurs on the crucible and rotational die-cutting machines. Working tools are a combined die-cutting form by which all operations are performed simultaneously during one operating run. This article describes the methodology of optimizing the main press mechanism of the die-cutting machine that enables improvement of productivity and manufacturing quality and also power reduction of machine drive. The authors investigated analytical dependencies of which synthesis is conducted and developed an application for the analysis and synthesis of investigated mechanisms.
BOOK QUALILOGY #2 (28) / 2015
ANALYSIS OF SOFTWARE FOR RESEARCH OF MECHANISMS OF PRINTING AND PACKAGING PRESSES
V. V. Vlakh
Kinematic and dynamic mechanisms analysis is necessary to develop new printing and packaging presses and improve existing ones. Today, there are many types of software that you can use to calculate mechanisms on kinematic and dynamic characteristics. The Internet analysis has shown that professional CAD, which enables kinematic and dynamic analysis, needs additional knowledge to work with them, has ample computer hardware resources, and is expensive. Several attempts by scientists and engineers to create a cheap, easy-to-use, and feature-rich tool have failed. In Europe and the US, they have developed solutions that can be used only in professional, robust systems. So, creating multifunctional, easy-to-use, inexpensive software for calculating mechanisms is essential.
SCIENTIFIC NOTES (Lutsk, LNTU) #48 / 2015
RESEARCH MECHANISMS OF PRINTING AND PACKING MACHINES IN SPECIALIZED CAD
V. V. Vlakh
The author of this article has created a computer program to calculate mechanisms. The first version of the program allows us to visually create a kinematic scheme of the investigated mechanism, see an animation of the motion, do kinematic analysis, and get a 3D model that can be applied to other, more powerful systems. The program can be used in the educational process. This article describes the possibilities offered by this CAD on example analysis of mechanisms of printing and packaging machines.
Vetsnik NTU “KPI” 2015, #35 (1144)
METHODOLOGY OF IMPLEMENTATION OF DATA EXPORT, VISUALIZATION AND CREATING 3D MODEL OF MECHANISM IN SPECIAL CALCULATION SYSTEM
V. V. Vlakh
The article explains the visualizing mechanisms and data transfer methods from specialized software to AutoCAD. The software was developed in Embarcadero Rad Studio Delphi using object-oriented programming methods. That essentially enabled the export of the mechanism kinematic scheme and the creation of the AutoLisp program, which describes the 3D model.
SCIENTIFIC NOTES (Lviv, UAD) # 4 (49) / 2014
THE AUTOMATED KINEMATICS ANALYSIS OF LEVER MECHANISMS OF PRINTING AND PACKING MACHINES WITH PERMANENT LENGTHS OF LINKS
V. V. Vlakh, V. R. Pasika, S. M. Komarov
The hierarchically composed software was developed to analyze the kinematic parameters of linkages. The software was created on Embarcadero RAD Studio XE using the base of classes library VCL and object-oriented programming.
Computer-integrated technologies: education, science, production #6, 2011
COMPUTER KINEMATIC ANALYSIS OF MECHANISMS OF THE SECOND CLASS OF ARBITRARY STRUCTURE
V. V. Vlakh, V. R. Pasika, S. M. Komarov
The article describes a computer program for kinematic analysis of mechanisms of the second class. The mechanism analysis is done by dividing into groups of Assur.
PRINTING AND PUBLISHING * 2017/1(73)
MODIFICATION OF THE DRIVE MECHANISM OF THE PRESS PLATE IN THE DIE-CUTTING PRESS
V. О. Kuznetsov, I. І. Rehey, V. V. Vlakh
The article is focused on designing a drive mechanism for a press plate used in the die-cutting units. It has been identified that the pressure plate is driven via a hinge-lever mechanism that creates the «unwedging» effect necessary to overcome significant technological resistances in cardboard pattern manufacturing. The analysis of kinematic parameters of crosshead motion has been performed, and an asynchronous movement of left and right crossheads has been found. An alternative lower press plate drive mechanism has been designed based on master and slave couples of crank-crosshead contours. Mathematical dependencies have been derived to evaluate the kinematic motion of press plate crossheads. It has been identified that the crossheads move in direct and reverse directions at the same speeds, providing a parallel position of a press plate relative to the surface of the immovable support plate. The punching process is completed with no acceleration of the moving plates.
PRINTING AND PUBLISHING * 2016/1(71)
KINEMATIC SYNTHESIS OF DIE-CUTTING PRESS MECHANISM WITH EQUALITY OF FORWARD AND REVERSE MOVES
V. R. Pasika, V. V. Vlakh
The construction of die-cutting presses, which consist of the fixed plate with form, the pressure plate, the levering, and eccentric mechanisms, are characterized by drawbacks since the eccentric mechanisms installed diagonally on the drive shaft provide an oscillatory motion to the pressure plate for a period of working and idle moves. It has a negative effect on the quality of stamping of the cardboard sweeps, degrades the stability of the work of the press, and limits its performance. This article deals with the kinematic synthesis of this mechanism, which increases the press’s productivity.
MAGAZINE UPAKOVKA (PACKAGING) # 6 (121)-2017
DRIVE MECHANISM OF THE PRESS PLATE OF THE DIE-CUTTING MACHINE
I.I. Regey, V.A. Kuznetsov, V.V. Vlakh
This article is considering a new mechanism of a drive of the press plate of the die-cutting machine. This is based on the combined mechanism of driving and driven slider-crank contours. The kinematic analysis describes that the sliders of the press plate move at the same speed, which also saves parallelism to the stationary plate. The press plate stops in an extreme position without acceleration.