scholarly journals Calculation of the chain drum with elastic fingers of potato harvesting machines

2021 ◽  
Vol 845 (1) ◽  
pp. 012133
Author(s):  
N G Bayboboev ◽  
U G Goyipov ◽  
A A Tursunov ◽  
Sh B Akbarov

Abstract In agricultural machines, chain transmission is widely used, the main advantage of which is a high load capacity. Therefore, in this article, the methodology for calculating chain drives in mechanical drives of agricultural machinery, namely in mechanical drives of potato harvesters, is presented. As a result of experimental and theoretical studies, the availability and safety margin of the selected chain drive of a loosening drum with elastic fingers of a potato harvesting machine was confirmed. In potato-harvesting machines, the movement of the executive working bodies is carried out. Analysis of the design of domestic and foreign potato harvesters showed that it is possible to obtain a good quality of potato harvesting in difficult soil and climatic conditions due to the use of machines of a simpler design with a mesh number of working bodies, but at the same time with their rational layout, the correct choice of transmission drives and ensured optimal modes work. The advantage of these transmissions is their large load capacity and the ability to work under dynamic loads. Therefore, in these investigations, the works are analyzed and the theoretical foundations and methods for calculating the working capacity of the wearable chain and the margin of strength of the chain transmission for dynamic loads are presented. As a result of the experimental theoretical research, the reliability of the working capacity and the strength reserve of the selected chain drive of the drum with elastic pulleys of the potato harvester is supported.

Author(s):  
Д.В. ЕВТЕХОВ ◽  
Р.В. БЕЗНОСЮК ◽  
С.Т. КОДИРОВ ◽  
Г.К. РЕМБАЛОВИЧ ◽  
Н.С. ЖБАНОВ

Проблема и цель. В процессе уборки картофеля меняются почвенно-климатические условия, урожайность, свойства убираемых клубней и поэтому уборочный комплекс должен гибко реагировать на эти изменения. Это предполагает не только своевременную настройку рабочих органов, но и более широкие возможности современных картофелеуборочных машин. Цель – совершенствование картофелеуборочных машин на основе применения полимерных и композиционных материалов. Методология. Появление в бункере комбайна клубней с повреждениями, ушибами (потемнение мякоти) свидетельствует о значительных динамических нагрузках рабочих органов. Предлагаемый сепарирующий элеватор имеет гибкие композиционные прутки, которые взаимодействуют с обрезиненными роликами-интенсификаторами и при движении образуют волнообразную, постоянно меняющуюся поверхность. При поступлении картофельного вороха гибкие композиционные прутки прогибаются, причем чем больше масса поступающего картофельного вороха, тем больше величина прогиба прутков. При изменении почвенно-климатических условий значительная нагрузка приходится на органы выносной сепарации, поэтому увеличение производительности и снижение повреждений клубней является важной задачей. Для повышения эффективности работы продольной прямоточной пальчиковой горки был предложен многокулачковый встряхиватель с регулируемой частотой и амплитудой воздействия. Благодаря колебательным воздействиям полотна пальчиковой горки картофель приобретает дополнительную подвижность, что позволяет более полно использовать различия физико-механических свойств клубней и примесей. Результаты. Применение сепарирующего элеватора с композиционными прутками увеличило сепарирующую способность картофелекопателя на суглинке нормальной влажности (22 %) и снизило повреждения клубней на 2,6 %. Сравнительные показатели качества работы комбайна Grimme DR-1500, оборудованного модернизированной горкой с многокулачковым всряхивателем и серийного комбайна Grimme DR-1500 соответственно составили: полнота уборки – 97,3 % и 95,8 %; полнота выделения примесей – 94,1% и 86,8 %; процент повреждений клубней –2,47 % и 3,15 %. Заключение. Увеличение интенсивности сепарации на рабочих органах из композиционных и полимерных материалов позволяет увеличить производительность картофелеуборочных машин. Problem and purpose. In the process of harvesting potatoes, the soil and climatic conditions change, the yield properties of the harvested tubers, and therefore the harvesting complex must respond fexibly to these changes. This presupposes not only the timely adjustment of the working bodies, but also the wider possibilities of modern potato harvesters. The goal is to improve potato harvesters based on the use of polymer and composite materials. Methodology. The appearance of tubers with injuries in the bunker of the combine with bruises (darkening of the pulp) indicates signifcant dynamic loads of the working organs. The proposed separating elevator has fexible composite rods, which interact with rubberized intensifer rollers and, when moving, form a wavy, constantly changing surface. When the potato heap arrives, the fexible composite rods bend, and the greater the mass of the heap, the greater the defection. With a change in soil and climatic conditions, a signifcant load falls on the external separation organs, therefore, increasing productivity and reducing damage to tubers is an important task. To increase the efciency of the longitudinal direct-fow hedgehog slide, a multi-cam shaker with an adjustable frequency and amplitude of action was proposed. Owing to the vibrational efects of the hedgehog slider, the potato acquires additional mobility, which allows more full use of the diferences in the physical and mechanical properties of tubers and impurities. Results. The use of a separating elevator with composite rods increased the separating capacity of a potato digger on loam of normal moisture content (22%) and reduced damage to tubers by 2.6%. Comparative performance indicators of the Grimme DR-1500 combine equipped with a modernized slide with a multi-cam shaker and the Grimme DR-1500 serial combine, respectively, were: completeness of cleaning –97.3% and 95.8%; completeness of separation of impurities – 94.1% and 86.8%; percentage of damage to tubers –2.47% and 3.15%. Conclusion. An increase in the intensity of separation on working bodies made of composite and polymer materials allows increasing the productivity of potato harvesters.


2021 ◽  
Vol 4 (1) ◽  
pp. 29-35
Author(s):  
Nafisa Saidho’jaeva ◽  

The article deals with the calculation of the drive and chain transmission of the newly created mechanized drying plant for drying melon slices. The essence of the utility model: the machine contains a horizontal tunnel chamber, inside which is mounted a chain conveyor with driving and driven sprockets, load-carrying elements, the IR emitters with reflectors on top of the camera mounted electric air heater, fan, an annular heat exchanger equipped with inlet and outlet nozzles of the drying agent. On the branches of the conveyor chain, lodgments with folding clamps are mounted, on which load-bearing elements are fixed, which are used as wooden poles. The calculation of the drive and chain transmission of the drying plant conveyor was carried out according to the existing method according to the scheme shown in the figure. Thus, the main parameters of the drive and chain transmission parts of the mechanized chamber-chain drying plant for drying melon fruits were determined by calculation


2021 ◽  
Vol 346 ◽  
pp. 03014
Author(s):  
Anton Letopolsky ◽  
Pavel Korchagin ◽  
Irina Teterina

The article presents a variant for improving the design of a working body of a tunneling shield, its cutting part to be more precise. The working body of the tunneling shield has been improved with the changes in the design of a rotor working surface. The theoretical studies aimed at determining the strength characteristics of the proposed rotor design have been carried out. The proposed rotor model has been visualized with the use of the T-Flex CAD software. On the basis of the results obtained in the course of the theoretical research, a comparative analysis of the strength characteristics of the main and improved model of the cutting working body of the tunneling shield have been made. The studies carried out at T-Flex CAD confirmed the working capacity of the improved design of the tunneling shield working body. The strength of the rotor has been determined as a result of the studies carried out. The maximum values of the displacement module is 2.875E-05 m, the equivalent stresses are 29.47 MPa, a reserve coefficient on equivalent stresses is 9.446E 06.


2020 ◽  
Vol 92 (9) ◽  
pp. 1319-1326
Author(s):  
Robert Goraj

Purpose This paper aims to present airworthiness considerations regarding a shaft of an electric motor. A fatigue lifetime prediction analysis based on one-step load spectrum is performed during high-cycle fatigue. Time-dependent normal and shear stress components are estimated using a high-fidelity digital twin built in Siemens PLM Nx Nastran as a finite element model (FEM). Linear and centrifugal acceleration as well as gyroscopic moment, motor torque, propeller thrust and thermal loads are considered. The equivalent cyclic degree of utilisation and a safety margin against the slip of a press-fitted shaft to rotor hub connection is estimated. Design/methodology/approach A load analysis using FEM is presented. The numerically obtained results are verified on an analytical and a semi-empirical basis. Findings The shaft of the electric motor can sustain 74 h of operation if burdened with aerobatic loads. Its load capacity equals 48% for the overall safety factor of 2.25. Practical implications The paper presents a specific, easily identifiable advance in knowledge that can be applicable in safety flight analysis issues. Originality/value The work presents a rotor of a novel lightweight electric motor for aircraft applications, which is a successor of the electric motor set recently in Extra 330E. The work delivers a computational estimation of the shaft life.


2020 ◽  
Vol 307 ◽  
pp. 01051
Author(s):  
Soumaïla TIGAMPO ◽  
Vincent SAMBOU ◽  
Younouss DIEYE ◽  
Pape Moussa TOURE ◽  
Séckou BODIAN

Sun drying is the oldest way to preserve but also to valorize and store surplus agricultural production. Nowadays, several types of dryers have been developed, but the solar greenhouse dryer is an ideal solution in our tropical countries because of its implicit and higher load capacity. The greenhouse climate depends on several factors, namely the outdoor climatic conditions (air temperature, wind speed, radiation, etc.) but also on the type of materials used to cover the greenhouse. The study was carried out on a parabolic greenhouse covered by a polyethylene film with a concrete base (absorber) which in turn is placed on the ground and will be tested under the climatic conditions of Dakar, Senegal. It is in this context of sustainable development that this work is carried out. The goal is to determine the distribution of temperatures and wind speeds in the greenhouse. The simulation was carried out using the three-dimensional computer fluid dynamics software (CFD). The turbulence method (k-ε) was used and to solve the radiation transfer equation (RTE) we introduce the discrete ordered method DO. We also add the “Solar Load Model” which gives the position of the sun and its radiations in relation to the layout of the greenhouse according to the date and time of the simulation. The simulation is carried out in a closed greenhouse and the results found can be used to improve the design and control of the greenhouse climate. Air temperatures and velocities simulation give an average of 325.95 K and 0.114 m/s respectively.


2021 ◽  
pp. 31-53
Author(s):  
Oleksandr Safronov ◽  
◽  
Andrii Sulym ◽  
Pavlo Khozia ◽  
Yurii Vodiannikov ◽  
...  

Improving the reliability of test results is achieved by applying more advanced methods of recording and processing the results. Therefore, an important part of the study of the strength of freight wagons is the choice of methods for obtaining, processing and analyzing experimental data. The article outlines the procedure and algorithms for determining the equivalent stresses under longitudinal and dynamic loads acting during operation. It is shown that algorithms for determining stresses generated by dynamic longitudinal and vertical forces are significantly different due to various load application schemes. Thus, the testing of freight wagons under dynamic longitudinal loads is carried out by the impact against an experimental wagon, and testing under dynamic vertical forces is performed during the wagon motion in the composition of the experimental train on the characteristic, pre-selected (planned) sections of the railway track at specified speeds. To estimate the level of loading of the freight wagon structureunder vertical dynamic loads, a method based on the replacement of a real random process is used by some schematized process, which in terms of the fatigue damage accumulation should be equivalent to a real process. From the whole variety of schematic methods, two methods stand out, i.e., the full cycle method and the rainflow method, which most fully represent the real process.The advantage of the rainflow method is the ability to process the process in real time. However, the algorithm of the rainflow method is quite complicated and does not allow processing large amounts of information. In this regard, a method of maximum discharge was proposed, which is a kind of full cycles method and allows you to process an unlimited amount of information online. An example specified in GOST 25.101 was used for a comparative analysis of the rainflow and maximum discharge methods. Analysis showed a satisfactory matching of both methods. Based on the procedure outlined, the block structure of the computational process is proposed to determine the equivalent reduced voltage amplitude. Each block displays the impact of the forces depending on the loading condition, that is, longitudinal impact force and dynamic forces when the wagon is moving on straight track sections, curves and switches of the railway track. Key words: wagon car, process, dynamic load, longitudinal load, voltage, amplitude, algorithm, equivalent stress, safety margin, strength.


2020 ◽  
Vol 21 (3) ◽  
pp. 321-331
Author(s):  
V. A. Sysuev ◽  
S. L. Demshin ◽  
D. A. Cheremisinov ◽  
M. S. Doronin

Increasing the efficiency of direct strip sowing of grass seeds by means of seeders with active furrow openers is possible when seed and fertilizer working bodies are removed from the zone of operation of disk milling cutters. A structural and technological scheme of the coulter group of the sod seeder for strip sowing is proposed, which consists of a milling furrow opener, fertilizer and seed coulters mounted on leashes in the form of torsion spring trailers, and a rolling roller. To ensure high quality multilevel sowing of grass seeds and granules of mineral fertilizers, it is necessary at the design stage to determine the length of the fertilizer coulter sides, which prevent premature shedding of soil from the furrow walls until the mineral fertilizer granules reach the bottom of the furrow, and the minimum allowable distance between the fertilizer and seed coulters, which allows to cover the granules of mineral fertilizers with soil completely while maintaining the compact design of the coulter group. In the course of theoretical research, mathematical dependences were obtained to determine the rational parameters and operating modes of the coulter group of the proposed design, which will ensure a minimum spread of mineral fertilizer granules over the depth of incorporation and a high stability of the soil layer thickness between mineral fertilizer granules and grass seeds. Rational parameters of the coulter group of the proposed design are determined for the range of operating speeds of the sod seeder for strip sowing: angle at the apex of the shank fertilizer coulter in the horizontal plane is 15-20º, the length of the fertilizer coulter sides is 0.040-0.045 m, the width of the fertilizer coulter bell is 0.02 m, minimum permissible distance between the fertilizer and seed coulters is 0.14-0.16 м.


2020 ◽  
Vol 11 (3) ◽  
pp. 143-150
Author(s):  
I. L. Rogovskii ◽  

In the article the analysis of existing agricultural machines in a healthy state, followed by work on the maintenance system subject to the conditions of reforming of the agrarian sector. Under maintenance refers to the complex of works on maintenance of working capacity or serviceability of the products during use by adjusting, knowledgeable, filling and retaining work. For the assessment of the alternatives it is advisable to conduct morphological analysis of the entire set of possible solutions to the research problem presented in a morphological matrix, which presents the basic functions of the machine and options the subject of the forms of their implementation. Theoretical research has provided the answer to two fundamental questions – how to change maintenance system depending on the level of development of agricultural production, and what parameters must have the system maintenance service to perform the appropriate intervention with the minimum technologically necessary costs of resources and investment. Assessment of the level of maintenance of agricultural machinery is provided to carry on the totality of organizational and technical factors, formalized through parts and complex indicators, in two phases. The first evaluation of using of the indicators for each factor separately. Second – assessment of a complex indicator (for all factors).


Fan sprayers such as OVH-600 and VP-1 are of indisputable importance in the fight against agricultural pests and diseases, but they have significant disadvantages associated with uneven application of pesticides due to the oscillating movement of their working bodies. To eliminate this drawback, the Agrikhim joint venture developed a universal fan sprayer VP1IB, which processes field crops, orchards and vineyards based on controlled airborne droplets with simultaneous continuous girth of the entire implement width within ± 900 of the sprayer symmetry axis (in a total of 1800), i.e. around the perimeter of the treatment area. The main working element of the universal fan sprayer is the spraying tips quality performance indicators, which largely depends on the correct choice of parameters of its parts, including the radius of the input channels to the swirl chamber on the swirl disk, to justify the rational value of which this article is aimed.


2021 ◽  
Vol 1 (7 (109)) ◽  
pp. 51-62
Author(s):  
Ivan Galych ◽  
Roman Antoshchenkov ◽  
Viktor Antoshchenkov ◽  
Igor Lukjanov ◽  
Sergey Diundik ◽  
...  

Results of theoretical studies of dynamics of the machine-tractor assembly taking into account the influence of a bearing surface profile were presented. It was established that in the course of operation, the machine-tractor assembly is exposed to a number of external factors leading to a change of vertical loads on the chassis and the engine. Mathematical models of dynamics of a tractor and a machine and a tractor unit consisting of a tractor of pivotally connected arrangement and a trailed sower were constructed. Such models make it possible to study dynamics and oscillatory processes of multi-element units. A mathematical model of tractor wheel dynamics was formed. Speeds and angles of orientation of elements of the machine-tractor assembly in space were determined. Influence of profile of the bearing surface on the unit elements when moving in the field prepared for sowing and the field after plowing was calculated. Theoretical studies of the influence of the bearing surface profile on dynamics of the machine-tractor assembly were performed on the example of KhTZ-242K tractor and Vega-8 Profi sower (Ukraine). When moving, the sower frame has a smaller amplitude of vibration accelerations than that of the tractor. Accordingly, the tractor has higher oscillation energy because it rests on the ground through its wheels having appropriate stiffness. The sower moves with its working bodies immersed into the soil which leads to a decrease in the amplitude of oscillations. The highest energy of amplitude of oscillation accelerations of the sower frame in the vertical direction was observed at frequencies of 15.9; 23.44; 35.3 and 42.87 Hz. It was found that the increase in working speeds of agricultural units leads to the fact that oscillations of all components reach significant values. This entails an increase in dynamic loads on soil and, as a consequence, its compaction


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