scholarly journals ЗАСТОСУВАННЯ МЕХАНІЗМУ ЧЕТВЕРТОГО КЛАСУ ДЛЯ ПРИВОДУ ВУШКОВИХ ГОЛОК ОСНОВОВ’ЯЗАЛЬНОЇ МАШИНИ

2021 ◽  
Vol 146 (3) ◽  
pp. 15-24
Author(s):  
В. М. Дворжак
Keyword(s):  
Random Search ◽  
Second Order ◽  
Geometrical Parameters ◽  
Kinematic Scheme ◽  
Structural Group ◽  
Light Industry ◽  
Fourth Class ◽  
Link Mechanism ◽  
Characteristic Points ◽  
Working Bodies

Development and research of functionally-adequate target mechanisms of technological machines of light industry with application of applied CAE-programs. Used the apparatus of vector algebra; analytical and numerical methods for determining the position functions of planar mechanisms containing a structural group of the fourth class of the second order, based on the vector transformation of coordinates; random search method for metric synthesis of flat mechanisms; methods of computer visualization and animation of kinematic schemes of flat mechanisms of higher classes. Mathematical models describing the position functions of the mechanism of eyelets of a warp knitting machine containing a structural group of the fourth class of the second order with rotating kinematic pairs in the form of angles of moving links, free vectors constructed on these links and radius vectors of characteristic points of the mechanism as a function of the angle of rotation of the master crank. The geometrical parameters of the flat six-link mechanism of eyelets for the warp knitting machine containing the structural group of the fourth class of the second order with rotating kinematic pairs as a result of metric synthesis of the mechanism by random search in CAE-program are determined; computer circuit modeling of the obtained mechanism is performed; graphs of visualization and animation of the kinematic scheme of the received mechanism are constructed; identification of the kinematic scheme of the obtained mechanism for compliance with the accepted structure; the received graph of function of position of an auricular needle of the mechanism of the fourth class; the functions of the position of the eye needle of the new mechanism and the mechanism of the basic knitting machine OV-7 are compared. The structure of a flat six-link mechanism, containing structural groups of the fourth class of the second order with rotating kinematic pairs, is proposed for use as a drive in a warp knitting machine on the example of the mechanism of oscillating movement of eyelets. The geometric dimensions of the moving parts of the functionally adequate mechanism of the fourth class for the drive of the eye needles of the basic knitting machine are determined. Software blocks for automated computer metric synthesis and calculation of link angles and radius vectors of characteristic points of the mechanism in the CAE program have been created. Practical Value is to use the results for the design and construction of flat mechanisms of the fourth class with rotating kinematic pairs of warp knitting machines, in which the working bodies make stops during the work process.

scholarly journals ANALYSIS OF THE REVERSING MECHANISM OF LIGHT INDUSTRY EQUIPMENT

2021 ◽  
Vol 1 (63) ◽  
pp. 38-43
Author(s):  
S. Koshel ◽  
◽  
G. Koshel ◽  
Keyword(s):  
Angular Acceleration ◽  
Loop Formation ◽  
Light Industry ◽  
Quality Performance ◽  
Equipment Operation ◽  
Cyclic Movement ◽  
Working Bodies ◽  
The Right ◽  
Logical Process ◽  
Selection Of

To create reliable and highly efficient, en- ergy-saving machines for light industry, it is necessary to study the dynamic processes of movement of the links of the mechanisms of which they are composed. Especially such studies should be given attention for machines, the mechanisms of which have a cyclic nature of action. During the execution of a technological operation in light industry machines with a periodic cyclic movement of the working bodies, an uneven movement of the main shaft occurs. This is caused by the movement of the links of the mechanism with certain accelerations and taking into account the periodic nature of the action of technological loads, which vary in magnitude and direction. The uneven nature of the movement leads to the appearance of additional loads in the kinematic pairs of mechanisms, mechanical vibrations in the mechanical trans- mission systems of motion, leads to the appearance of vibrations and violations in the positioning of the working bodies, affects the techno- logical process of the equipment. Uniform and stable tension of the threads is the key to a high-quality performance of the loop formation process in knitwear. Additional dynamic loads affect the technological tension of textile threads during equipment operation. These loads are caused by the accelerated movement of the links of the mechanism, which is especially important for technological equipment with the pres- ence of a reverse working stroke of its links. In such mechanisms, the values of the angular acceleration of the links and the linear accelera- tion of their individual points can acquire critically permissible values. It is possible to ensure the movement of the working bodies of the machine according to the law for which the tension of the threads will be optimally necessary. To do this, you need to choose the right type of mechanism that sets them in motion. The aim of the work is to conduct a structural-kinematic research of the mechanism of the reversible movement of the needle drum of a knitting machine, which will justify the selection of the required type of mechanism for such equipment. The confirmation of the improvement of the conditions for the formation of loops when knitting on a knitting machine with a reversible needle drum movement, made on the basis of a rocker mechanism, has been obtained.

Influence of geometric parameters of screw nozzles of twin-screw extruder-press on oil yield

2021 ◽  
Vol 12 (3) ◽  
Author(s):  
M. M. Gudzenko ◽  
◽  
V. P. Vasyliv ◽  
M. M. Mushtruk ◽  
M. M. Zheplinska ◽  
...  
Keyword(s):  
Free Volume ◽  
Geometric Parameters ◽  
Oil Yield ◽  
General Nature ◽  
Geometrical Parameters ◽  
Twin Screw Extruder ◽  
Screw Extruder ◽  
Twin Screw ◽  
Working Bodies ◽  
Selection Of

In modern economic conditions, the chosen technology of raw material processing and the choice of the necessary equipment for both the line as a whole and the oil press are of great importance in oil production. In small-capacity workshops, screw presses of various designs are used. The twin-screw extruder occupied a certain niche among the press equipment with a productivity of 150–500 kg/h. Their use can significantly simplify the technology of oilseed processing. They combine operations of heat treatment, grinding, and pressing of vegetable oil. It is important to study the influence of geometric parameters of the oil pressure path and screw nozzle on the oil yield. In twin-screw extruders, it is rational to choose the pitch of the worm, the width of the channel between the turns, the width of the crest of the turn and the length of the nozzle with variable geometrical parameters. The analysis and selection of geometrical parameters of working bodies of a twin-screw extruder on the basis of theoretical calculations are carried out. Two sets of experimental working bodies with the changed geometrical parameters are made. Their theoretical degree of compression is determined, which is 5.50, 4.69, and 4.33, respectively. It is experimentally confirmed that the oil yield depends on the degree of compression due to the geometric parameters of the screw. The effect of a sharp drop in the free volume of the screw on the energy performance and press extruder performance has been revealed. The general nature of the change in the free volume in the areas of nozzle groups is accompanied by an uneven decrease of 40–80% towards the release of oil cake. The nature of the change in the free volume of turns along the length of the screw shaft characterizes the correctness of its design. The selection of rational geometric parameters of the working bodies should be considered in combination with other design parameters, which will intensify the process of oil pressing.

scholarly journals Redundancy principle for optimal random search in biology

2017 ◽  
Author(s):  
Z. Schuss ◽  
K. Basnayake ◽  
D. Holcman
Keyword(s):  
Brownian Particle ◽  
Random Search ◽  
First Passage Time ◽  
Diffusion Flux ◽  
Chemical Activation ◽  
Nonlinear Dependence ◽  
Forward Rate ◽  
Geometrical Parameters ◽  
Activation Time ◽  
The Mean

AbstractChemical activation rate is traditionally determined by the diffusion flux into an absorbing ball, as computed by Smoluchowski in 1916. Thus the rate is set by the mean first passage time (MFPT) of a Brownian particle to a small target. This paradigm is shifted in this manuscript to set the time scale of activation in cellular biology to the mean time of the first among many arrivals of particles at the activation site. This rate is very different from the MFPT and depends on different geometrical parameters. The shift calls for the reconsideration of physical modeling such as deterministic and stochastic chemical reactions based on the traditional forward rate, especially for fast activation processes occurring in living cells. Consequently, the biological activation time is not necessarily exponential. The new paradigm clarifies the role of population redundancy in accelerating search processes and in defining cellular-activation time scales. This is the case, for example, in cellular transduction or in the nonlinear dependence of fertilization rate on the number of spermatozoa. We conclude that statistics of the extreme set the new laws of biology, which can be very different from the physical laws derived for individuals.

scholarly journals DYNAMIC FORCE RESEARCH OF ASSUR CYLINDRICAL JOINTED GROUP OF THE FOURTH CLASS OF THE SECOND ORDER

2019 ◽  
Vol 269 (1) ◽  
pp. 12-16
Author(s):  
R. V. AMBARTSUMYANTS ◽  
◽  
A. P. LIPIN ◽  
S. A. RОМАSHKЕVICH ◽  
Keyword(s):  
Second Order ◽  
Dynamic Force ◽  
Fourth Class

scholarly journals Substantiation of the parameters of the disk-knife working body and the study of its work 

2018 ◽  
Vol 64 (No. 4) ◽  
pp. 195-201
Author(s):  
Savelii Kukharets ◽  
Gennadii Golub ◽  
Viktor Biletskii ◽  
Oleksandr Medvedskii
Keyword(s):  
Analytical Model ◽  
Equations Of Motion ◽  
Soil Layer ◽  
Comparative Test ◽  
The Body ◽  
Geometrical Parameters ◽  
Plant Remains ◽  
Working Bodies ◽  
The Individual

The work is devoted to the issue of improving the quality of cultivating of root-bearing soil layer and optimizing its agrotechnological properties. Improving the quality of cultivation is due to the application of soil cultivating tools equipped with disk-knife working bodies. They are provided theoretical and experimental study of the work of the disk-knife working body, and it is substantiated its rational parameters. The basis of the substantiation of the parameters of the cultivating tool is the original analytical model, which reflects the process of interaction of the working body with the soil. To study the performance of the process, on the basis of kinematic equations of motion of the individual points of the working bodies, it is developed the analytical model of the motion of the battery of the working bodies. On the basis of the provided analytical researches, they were determined geometrical parameters and developed experimental samples of the disk-knife working body. It was carried out a comparative test in the field of tools equipped with disk-knife working bodies and with standard spherical cut-off discs, which confirmed the effectiveness of the use of disk-knife working bodies. The use of disk-knife working bodies ensures: the burying of plant remains and fertilizers into the root-bearing soil layer, improving the quality of soil cultivation, preserving of its structure, reducing the traction resistance of the body.

Influence of Distributor Parameters on the Quality of Fertilizer Scattering in the Under-foot Space

2020 ◽  
pp. 12-19
Author(s):  
Viktor Deikun ◽  
◽  
Dmytro Artemenko ◽  
Svitlana Deikun ◽  
◽  
...  
Keyword(s):  
Traditional Approach ◽  
Theoretical Research ◽  
Normal Operation ◽  
Mineral Fertilizers ◽  
Geometrical Parameters ◽  
Factors Affecting ◽  
Maximum Range ◽  
Working Bodies ◽  
The Given

The aim of the work is to substantiate the geometric parameters of the distributor, which are able to provide the maximum range of fertilizer particles in the subclavian space, based on the analysis of all factors affecting the material particles during their transportation to the surface of the distributor. The result of research is to achieve a uniform distribution of fertilizers on the width of the capture and, accordingly, on the area. It is known that the particles of material sent in accordance with the given trajectories in the pre-provided areas of the surface of the furrow formed by the working body, in contact with the soil are significantly redistributed and the meaning of the traditional approach to uniformity is completely lost. In addition, it is necessary to take into account that for placing fertilizers in the soil, in most cases, flat-cutting working bodies are used. For normal operation, in terms of deepening into the ground, they must be installed with a forward tilt at an angle of up to 3°. As a result, the bottom of the furrow, which they form, acquires a conical shape with a slope to the center. In this case, it becomes obvious that the material must be fed not evenly across the width of the working body, and most of it to be directed at a clearly defined distance in the direction perpendicular to its axis. The numerical value of this distance is determined by the nature of the redistribution of the granules as a result of contact with the soil. In the process of rolling the granules or particles to the center, the uniformity of distribution will be restored. In this case, it becomes obvious that the material must be fed not evenly across the width of the working body, and most of it to be directed at a clearly defined distance in the direction perpendicular to its axis. The numerical value of this distance is determined by the nature of the redistribution of the granules as a result of contact with the soil. In the process of rolling the granules or particles to the center, the uniformity of distribution will be restored. In this regard, there is a need to solve the problem of ensuring the maximum range of particles in the transverse direction using the simplest geometry of the distributor surface. In our opinion, such a surface can be a prism. In the article the results of theoretical research of process of portage and distributing of granules of mineral fertilizers are resulted after a reflection from the plane of reflection in sub paw space of trivial cutting of working organ. Geometrical parameters and corners of location of reflecting plane are grounded. The obtained dependences allow to reasonably establish geometrical parameters of the distributor which will provide the set range of flight of particles of material for working bodies of various width of capture and to reach desirable result taking into account laws of their redistribution at contact with soil.

Free Vibration Analysis of FG Skew Plates Based on Second Order Shear Deformation Theory

2014 ◽  
Author(s):  
Firooz Bakhtiari-Nejad ◽  
Mahnaz Shamshirsaz ◽  
Mohammad Mohammadzadeh ◽  
Sasan Samie
Keyword(s):  
Partial Differential Equations ◽  
Differential Equations ◽  
Free Vibration ◽  
Shear Deformation ◽  
Vibration Analysis ◽  
Shear Deformation Theory ◽  
Free Vibration Analysis ◽  
Second Order ◽  
Geometrical Parameters ◽  
Partial Differential

In this paper free vibration analysis of skew plates with fully clamped boundary condition made of functionally graded materials is investigated. The study is based on the second order shear deformation plate theory (SSDT) using Generalized Differential Quadrature (GDQ) method. With a proper transformation, partial differential equations of a rectangular plate in Cartesian coordinates into skew coordinates are obtained; the governing differential equations are seven second order partial differential equations. The comparison of simulation results with those presented previously in the literature shows the accuracy of the proposed method. Also, fast rate of convergence is achieved by this method. Finally, the effects of angle of skew plate, power law index and plate geometrical parameters on the natural frequencies of the plate are also obtained and the related results are presented in this paper.

scholarly journals АНАЛІТИЧНЕ ДОСЛІДЖЕННЯ ДИНАМІКИ ТИПОВИХ КУЛІСНИХ МЕХАНІЗМІВ ТЕХНОЛОГІЧНИХ МАШИН ЛЕГКОЇ ПРОМИСЛОВОСТІ

2018 ◽  
Vol 122 (3) ◽  
pp. 9-18
Author(s):  
В. М. Дворжак
Keyword(s):  
Differential Equation ◽  
Computer Simulation ◽  
Angular Velocity ◽  
Equation Of Motion ◽  
Analytical Investigation ◽  
Light Industry ◽  
Sewing Machine ◽  
Characteristic Points ◽  
Crank Mechanism ◽  
Angle Of Rotation

Improving methods of designing technological machines mechanisms of light industry in CAD-programs. The analytical method of vector transformation of coordinates for calculation of typical mechanisms of technological machines and a numerical method for solving differential equations are used. Mathematical models describing the functions of the position of the moving links and the characteristic points of the multi-link mechanism of the thread take-up mechanism for the sewing machine and the dynamics of its operation are obtained. Schematic modeling of the mechanism in the Mathcad program was performed. The graphs of the dependence of the angular velocity and acceleration on time and on the angle of rotation of the crank mechanism. The algorithm of numerical and analytical investigation of the dynamics of the flat six-link articulated mechanism of the thread take-up of the sewing machine is proposed on the basis of the numerical solution of the differential equation of motion of the mechanism and a computer simulation of the mechanism in the program Mathcad. Practical Value is to use the results of research in kinematic and dynamic study of the target sewing machine mechanisms.

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