The current state of a question

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Table of contents

Introduction…………………………………………………………………………4

1 Literary review and analysis of development ……………………………………...6

2 Agrotechnical requirements ………………………………………………….……..9

3 The reasons of the choice of the designed car ……………………….……………10

4 Description of a design …………………………………………………...……….10

5 Technological calculations …………………………………………………..……13

5.1 Calculation of parameters of paws………………………………………..…….13

5.2 Justification of the scheme of arrangement of paws on a frame……….……….19

5.3 Calculation of the common traction resistance of a cultivator………..………..20

6 Design calculations ……………………………………………………...………..20

6.1 Strength calculation on a cultivator rack bend …………………………………21

6.2 Calculation on spring durability at torsion …………………...………………..22

7 Principal specification of a cultivator of KCT-3, 8………….……………………22

8 Action for the safe organization of field works ……………………....………….23

9 Safety measures at operation of soil-cultivating units ……………………….….24

10 Main adjustments of a cultivator ……………...………………………………..25

Сonclusion …………………………………….…………………………………25

Вibliography …………………………………….………………………………..26

Introduction.

Agriculture — the most ancient occupation of mankind. The related instruments of labor have centuries-old history of development and perfecting. Object of agriculture is the soil.

The soil — the surface layer of sushi of crust having fertility. The soil the main means of production in agriculture.

The soil is exposed to machining. A main objective of machining of the soil — creation of optimum conditions for body height and development of cultural plants and increase in its fertility. In the course of machining of the soil the action of the car or tool (a plow housing, a disk or tooth of a harrow, a cultivator paw, etc.), influences the soil therefore changes its properties and a state.

Productivity of crops in many respects depends on a way and quality of mekhanikchesky processing of the soil, one of the main pokazaktel of which — extent of dyeing. At an ispolzokvaniya of plows and blade cultivators it changes from 35 to 70%. However, the probability of obtaining neobkhodikmy value (80%) does not exceed 20, 4% because of the considerable variation of physicomechanical properties of the soil. The second important index physical a soil sostoyakniya — density, best value koktory for the processed chernozem layer in district windows of cultivation of winter and spring-sown field sostavklyat 1, 1... 1, 2 g/cm3. Excess of this value or excessive friability leads to decrease in an urozhayknost of grain crops. Very important under each culture to create the optimum density of the soil for smaller number of passes of the unit. Each poslekduyushchy dyeing of soil lumps is bound to increase in energy consumption at processing. They opkredelyatsya mainly by a type of breaking strains which in turn depends on geometrical and technological parameters, a kinekmatika of actions and physicomechanical properties of the soil. Because of their vacillation the same tools when processing eld various result: in one case exit pupils correspond to the required indicators of quality, in another - No.

The used soil-cultivating tools with passive actions have ogranichenkny opportunities of adjustment of technological pakrametr taking into account change of working conditions and a sokstoyaniye of the soil. In use tools change only of working speed and depth of an obkrabotka it is slightly possible to affect on indicators of a pochvoobrabotka.

In a zakvisimost from a reference state of the soil it is necessary to develop the actions having an opportunity to change the technological and geometrikchesky parameters for achievement of its necessary quality, that is they have to be adapktiruyemy that allows to operate technological processing of the soil quickly. For this pur pose actions equip with the supplementary equipments allowing to change their tekhknologichesky and geometrical parameters. They dolkzhna to change the provision of optimum addition of an arable layer, rather osnovkny for receiving, taking into account a reference state of the soil (a vlazhknost, density, a zadernennost, etc.). Tools with such of a rabochikma bodies will allow to operate quickly quality of processing of a pochkva by change of degree of their vozkdeystviye on layer, character of a deforkmation or trajectories of driving of particles.

Agrotechnical requirements.

The surface treatment of the soil — one of the most important agrotechnical actions of receiving big crops of crops. Its primal problems — to loosen the high layer of the soil on depth of crops of seeds, to level the surface of the field, to provide a melkokomkovaty structure of a sowing layer, to create the condensed bed at a depth of seal of seeds, to destroy shoots of weeds, to close up the introduced mineral fertilizers, to keep moisture in sowing and arable layers, to improve microbiological activity and the food mode of the soil, to create conditions for productive work of farm vehicles on crops, care of crops and harvesting.

Methods of the surface treatment of the soil change depending on soil climatic conditions, a land relief, the developing weather conditions, features of the grown-up cultures, system of fertilizers, character of a contamination of fields, presence of wreckers, diseases and many other conditions of concrete economy. There fore the rational flow diagram of this operation has to be based on evidence-based system of agriculture of each economy and its main link — systems of crop rotations. The surface treatment is differentiated depending on a species of the cultivated plants. Increase in the standard of farming, introduction in practice of high performance herbicides allow to minimize its receptions. On the basis of explained the choice of technological processes regulate the procedure sheet on cultivation of crops depending on soil climatic conditions and a condition of the field before processing.

For ensuring the required quality of the surface treatment with tillage machines it is necessary to know and to strictly keep agrotechnical requirements. The chief agronomist of economy establishes the terms and duration of carrying out processing of the soil necessary the combined machines and units according to agrotechnical terms, the developed weather conditions and the sizes of fields. If the obrakbotka consists of several receptions, then it is desirable not to lacerate them in vremekn.

Now destruction no more than 10-15% of an eddish for one pass of the car when processing on depth to 16 cm and no more than 15-20% is considered admissible when loosening on depth to 30 cm. Processing of the soil has to be carried out to the established agrotechnical terms at optimum humidity. Permissible variations of average depth of loosening from set should not exceed ± 1 cm when processing on depth to 16 cm and ± 2 cm with a depth up to 30 cm, and should not exceed fluctuations of depth on width of capture the 4-5th. On joints of passes and between paws of tools rollers no more than 5 SI high, and in places of passing of racks - furrows by width checking no more than 15 cm and no more than 8 cm in depth are allowed. Roots of weed plants and a fruit drop need to be cut completely at a depth of the course of actions. Flaws on a joint of interfacing passes of the tool are not allowed. Flaws or admissions are not allowed. As flaws most often appear as a result of negligent driving of the tractor, judge them by the form traces of actions of cars and tools. Traces have to be pryamolineynykm.

The ends of the site process also accurately, as well as the main site on which diversity in any index of a kachestkv should not be looked through (for example to a glybistost, a surface grebnistost, seal of a weed rastiktelnost and a dung). Most often diversity of these indexes — result of work at different speeds, and also negligent driving of the unit and the poor a sostoyakniya of actions of cars and tools (blunt edges, a rusty working poverkhknost).

At any processing it is desirable to receive lumps of the soil of 1 in Size... 10 mm are also undesirable — particles less than 0, 25 mm. These indexes depend on a type of processing and properties of the soil. They are hard-hitting, but are desirable.

Actions at the end of the processed site of the field should be switched on and off on one line; a permissible deviation — no more than ±0, 5 m.

To each type of processing of the soil are shown specific a trebovakniya. It is not allowed that bezotvalny tools for loosening of soils subject to a wind erosion destroyed more than 10% of an eddish for one pass at shallow loosening and more than 25% — at deep and that at the same time the soil разрушалась to particles less than 1 mm.

In the high loose coating of the soil, lumps more than 3 cm should not sokderzhatsya, the grebnistost of a surface of an arable land has to be no more than 3... 4 cm.

Estimating quality of operation of tillage machines, consider a sokblyudeniye of all agrotechnical requirements, remembering that the main thing from them - fight against weeds.

Cultivators for continuous processing of the soil have to process the soil on depth not less than 8 cm. The deviation of average depth from the given is allowed by ±3 cm. In the top processed layer of earth there should not be lumps more than 10 cm by the naikbolshy size. The surface of the field after pass by a disk harrow has to be conjoint, and depth the razvalnykh of furrows and height the svalnykh of crests - no more than depth of processing. Weed plants have to be cut not less than for 97%.

2. Initial parameters Input datas are given in tab. 8.1: B — width of capture of a cultivator, m; a — depth of processing, cm; bo — the design width of a rykhlitelny paw, mm; α — the angle of entry of a paw into the soil, a hail.; θ — a corner between the planes limiting area of deformation of the soil, a hail.; lo — a paw sock departure concerning a rack, mm; f — a soil friction coefficient about a paw.

Work of a cultivator paw

Input datas: from option No. 2, we choose data for calculation of the term paper (from the table of the appendix 2).

Type of the tillage machine cultivator; K constant of proportionality = 3

Half apex angle of sector φ = 310

Disk i point corner = 210

1. Capture width, In (m);

2. Working speed, (km/h);

3. Depth of processing of the soil, and (cm);

4. An angle of attack for creation of a profile of a furrow α = 200

Specific traction resistance of lancet paws with a width of capture of domestic cultivators by the 240-300th at traveling speed of 10 km/h is specified in tab. 1. tab. 1. Specific resistance of lancet cultivator paws

Глубина обработки, см.
Удельное сопротивление, Н/мм	0, 8-1, 0	0, 9-1, 3	2, 1-2, 7	3, 0-3, 8	3, 9-4, 7

At increase in traveling speed of a cultivator by 1 km/h (over 10 km/h) resistance of paws increases by 10%

Рисунок 11.Схема действия силы R_xz сопротивления почвы на лапу.

We accept q=3, 8 of N/mm as depth preseeding processing makes - 12 cm. We choose capture width maximal in =300 mm.

However resistance of paws of a forward row exceeds resistance of paws of a back row (with the same width of capture) approximately twice. It needs to be considered when determining traction resistance of a separate paw (21)

(22)

Then the traction resistance of paws is determined by analogy on a formula: (23)

(24)

Besides traction resistance, the paw is affected still by vertical resisting strength of the soil of Rz. (fig. 8).

m=tgΨ coefficient characterizing the relation of size of the vertical paw of Rz composing resistance to horizontal Rx depending on sharpness of an edge, hardness of the soil and depth of processing can change over a wide range and have both positive, and negative value. The negative value of a corner Ψ appears at solid dry soils and the blunt edge.

The direction of net force Rxz is defined by a corner Ψ and depends on the angle of dyeing β and a sliding angle φ:

As the angle of dyeing β from paw parameters, and a sliding angle φ – from properties and a condition of the soil, and a corner Ψ will be depends on them.

With a depth of course of 10 - 12 cm that corresponds to average humidity of the soil and a fine edge Ψ = 22-280. We accept Ψ = 31.

We calculate traction resistance for a forward number of a cultivator of Rxz a per:

We calculate traction resistance for the second and third ranks of a cultivator of Rxz the back:

The provision of a cross point of a force direction Rxz is characterized by the size h which depends on processing depth: (25)

We calculate Rxz point of application:

The common traction resistance of a cultivator is calculated by a formula:

Р= R_х_z_пер_*n+ R_х_z_зад_*n+ R_х_z_зад_*n (26)

where n-the number of paws among

As on the first row the number of paws of n = 5 pieces,

On the second row - n = 5 pieces,

On the third - n = 4 pieces, that common traction resistance will be: Р= 1087_*5+609_*5+609_*4= 11526 Н

We accept a traction class of the tractor of 30 kN. In that specific case we will take the tractor of the T-150K brand. 6 Design calculations.

CONCLUSION

During implementation of the term paper analysed actions of cultivators and on the basis of agrotechnical requirements, opened a substance of change of a design. Proved a principal specification of a new cultivator by means of calculations, proving a regularity of the choice of decisions. Made design calculations of new details of an action. Described the offered design, having explained explanations to service regulations of the car, also informed of safety regulationss at the working new tillage machine. By means of economic calculations proved profitability and profitability of this cultivator. This reconstruction of actions of tillage machines allowed to increase their effectiveness of use significantly. Also it was succeeded to increase efficiency of the unit and to reduce fuel consumption.

Вibliography

1. Дунаев П.Ф., Леликов О. П..Детали машин. Курсовое проектирование: Учеб. пособие для машиностроит. спец. техникумов.- М.: Высш. шк., 1984.-336с.,

2.Кленин Н.И., Сакун В.А. Сельскохозяйственные и мелиоративные машины: Элементы теории рабочих процессов, расчет регулировочных параметров и режимов работы.-2-е изд., перераб. и дополненное-М.: Колос, 1980.-671 с., -ил. (Учебники и учебные пособия для высш. учебн. с. –х. учеб. заведений).

3. Кушнарев А.С, Кочев В.И. Механико-технологические основы обработки почвы. — Киев: Урожай, 1989.

4. Панов И.М. Методы повышения эффективности обработки почвы // Исследование и разработка почвообрабатывающих и посевных машин: Сб. научн. тр. НПО ВИСХОМ.- М.: НПО ВИСХОМ, 1990.

5. Подскребко М.Д. Влияние скорости деформации на сопротивление почвы растяжению //Научн. тр. ЧИМЭСХ, вып. 56. - Челябинск, 1970.

6.Сабликов М.В. Сельскохозяйственные машины. Ч. 2. Основы теории и технологического расчета. (Учебники и учебные пособия для высш. учебн. с. –х. учеб. заведений). М., «Колос», 1968-296 с.

7. Сельскохозяйственные и мелиоративные машины/ Г.Е. Листопада.- М.: Агропромиздат, 1986.-688с., ил.- (Учебники и учебные пособия для высш. учебн. заведений).

8. Феодосьев В.И. Сопротивление материалов.-8-е издан., стереотип.-М.: Наука. Главная редакция физико-математической литературы, 1979.-560 с.

Table of contents

Introduction…………………………………………………………………………4

1 Literary review and analysis of development ……………………………………...6

2 Agrotechnical requirements ………………………………………………….……..9

3 The reasons of the choice of the designed car ……………………….……………10

4 Description of a design …………………………………………………...……….10

5 Technological calculations …………………………………………………..……13

5.1 Calculation of parameters of paws………………………………………..…….13

5.2 Justification of the scheme of arrangement of paws on a frame……….……….19

5.3 Calculation of the common traction resistance of a cultivator………..………..20

6 Design calculations ……………………………………………………...………..20

6.1 Strength calculation on a cultivator rack bend …………………………………21

6.2 Calculation on spring durability at torsion …………………...………………..22

7 Principal specification of a cultivator of KCT-3, 8………….……………………22

8 Action for the safe organization of field works ……………………....………….23

9 Safety measures at operation of soil-cultivating units ……………………….….24

10 Main adjustments of a cultivator ……………...………………………………..25

Сonclusion …………………………………….…………………………………25

Вibliography …………………………………….………………………………..26

Introduction.

Agriculture — the most ancient occupation of mankind. The related instruments of labor have centuries-old history of development and perfecting. Object of agriculture is the soil.

The soil — the surface layer of sushi of crust having fertility. The soil the main means of production in agriculture.

The current state of a question

1.1. The review and the analysis of the cultivators and actions existing designs

Cultivators are intended for the surface loosening of the soil (without reversing) and destructions of weed vegetation. They can also be used for an importation of mineral fertilizers and cutting of irrigation furrows.

To destination cultivators divide on steam (for continuous processing), propashny and express.

Steam cultivators use at care of couples and preparation of the soil for crops.

Spring preseeding cultivation of the soil is carried out in several days after a boronovaniye on depth of seal of seeds for destruction of shoots of weeds and creation of the condensed bed for seeds. Nonuniformity of depth of processing should not exceed ±1 cm. After cultivation the high layer of the soil has to be melkokomkovaty, and weed plants are completely cut. The bottom of a furrow and the surface of the field after cultivation have to be smooth, height of crests — no more than 4 cm. In the course of cultivation sublayers of the soil should not be taken out on a surface.

For the best alignment of the soil and preservation of moisture continuous cultivation of vapors and a ploughland is accompanied with a boronovaniye.

Propashny cultivators apply at care of propashny cultures, i.e. carry out interrow processing. With their help destroy weeds, loosen the soil in row-spacings and rows for the purpose of preservation of soil moisture, improvement of the air and food mode of plants, plants feed up. Interrow processing of some the propashnykh of cultures (for example, potatoes) consists in their earthing up.

Express cultivators use at care of such cultures as beet, melon, a cotton, and also behind gardens and tea plantations. Actions of cultivators. Cultivators supply with a set of removable actions. The main actions — ploskorezhushchy, universal and rykhlitelny paws.

Unilateral ploskorezhushchy paws, or razors (fig. 1, a), are intended for destruction of weeds. The flat vertical cheek 2 paws protect a row of cultural plants from a prisypaniye the soil. Such paws it is possible to process row-spacings with small protective zones (the raw strips of the soil to the right and to the left from a row axis), equal 6... 11 cm. Paws produce right and left-side capture from 85 to 250 mm wide for processing of row-spacings of various width. Along with cutting of weeds unilateral ploskorezhushchy paws loosen the soil on depth to 6 cm. The angle of installation of the plane of an edge to the surface of the field is equal 15 °.

Lancet ploskorezhushchy paws well cut weeds and loosen the soil on depth 4... 6 cm without carrying out of the lower, more wet layers of earth on a surface.

Lancet universal paws (fig. 1, b) apply to continuous and interrow processing of the soil on depth up to 14 cm. They well cut weeds and crumble the soil, partially taking out more wet layers on its surface. Lancet universal paws differ from the ploskorezhushchikh in the angle of dyeing ε. At the universal paws it is equal to 25...30 °, at the ploskorezhushchikh — 12... 18 °. Lancet paws produce with a cone angle γ equal 60 or 70 °, and capture wide 220... 385 mm.

Рис. 1. Рабочие органы культиваторов:

а- полольная лапа; б-стрельчатая универсальная лапа; в- долотообразная рыхлительная лапа; г- подкормочный нож; д-лапа-отвальчик; е-корпус-окучник; ж - корпус-окучник с решетчатым отвалом; з -арычник-бороздорез; и-секция игольчатых дисков; к-звено прополочной боронки; л-ротационная боронка БРУ-0, 7; м-щиток; 1-стойка; 2- щека; 3- лезвие; 4- раструб (воронка); 5-отнальчик; 6-крыло; 7-отвал; 8- наральник; 9- рама секции; 10-игольчатый диск; 11- пружина; 12- зуб боронки; 13- болт; 14-скоба; 15- рамка боронки; 16, 18- кронштейны; 17, 19- соответственно цилиндрический и конический барабаны; 20— поводок; 21— нажимная штанга.

Bit-shaped paws (fig. 1, c) use for loosening of the soil on depth up to 15 cm. They are carried out as a unit with a rack. Width of capture of such paws of 20 mm.

Fertilizer knives (fig. 1, d) apply to loosening of row-spacings and seal to the soil of fertilizers on depth up to 16 cm.

Bell 4 (a funnel for supply of fertilizers to the soil) fix to a bit-shaped paw. For leveling of a groove which remains after pass of a fertilizer knife behind it establish the second rykhliteljny or pro-half-internal paw.

Paws - otvaljchik (fig. 1, e) use at interrow processing of potatoes and other cultures. With Otvalchiki 5 with sharp edges weeds cut and loosen the soil on depth to 6 cm, moving it to protective zones and filling up with it weeds. Such actions apply when plants are small for an earthing up, and weeds gain strength.

To Okuchniki (fig. 1e, g) intended for cutting of crests, destructions of weeds in row-spacings and backfillings of weeds in protective zones. Okuchnik consists of a naralnik 8 and a bilateral dump 7s sliding wings 6 on which longitudinal adjusting grooves are provided. Regulating position of wings on a dump, it is possible to change an arrangement of the soil moved with an okuchnik, i.e. to change height of its crest. Okuchnikami process the soil on depth to 16 cm. At the same time height of crests can reach 25 cm.

Arychnik-borozdorez (fig. 1, h) differs from an okuchnik in existence of a funnel 4dlya importations of mineral fertilizers. It is used for cutting of irrigation furrows up to 20 cm in depth at interrow processing the propashnykh of cultures. Needle disks (fig. 1, i) apply to destruction of a soil crust and destruction of weeds in protective zones. For destruction of a soil crust disks establish so that the convex party of needles plunged into the soil, and for destruction of weeds change a rotation sense. Needles of disks enter the soil on depth to 4 cm and shift the surface layer on 1...2 see Disks produce with a diameter of 350, 450 or 520 mm.

Boronki (fig. 1, j) is used for loosening of the soil in row-spacings and protective zones. Spring teeths fix to a frame which for the best copying of a relief pivotally is connected with gryadily by cultivator sections.

On the propashnykh cultivators establish rotational boronka of BRU-0, 7 and protective guards for prevention of a backfilling of plants in rows by the loosened soil (fig. of 1 l, l).

For comb-out the kornevishchnykh of weeds in steam or the propashnykh cultures establish the reverse paws representing the plates 45 wide ground from two parties on spring racks... 60 mm.

Actions of cultivators fix to racks, rigidly or pivotally connected to a frame.

For continuous processing of the soil use cultivators with rigid racks for fastening of actions [KPS-4, KShU-6 (12; 18), KRG-3, 6], with spring racks (KShP-8, KPZ-9, 7), and also milling cultivators of KFG-3, 6.