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Badano metodą video-komputerową maksymalne gabaryty oraz powierzchnie przekroju bulw, a także pole powierzchni styky bulwy z powierzchnią trącą jako cechy odmianowe plonu ziemniaków.
Studies were carried out to determine selected physical properties of potato tubers, Ibis and Lawina cultivars, grown on medium-heavy soil (dusty loam) as well as the stones and earth clods taken from the same field. The coefficients of external friction, static and kinetic, were determined. Two kinds of friction surface were applied: fabric reinforced rubber and radially polished steel. The values of studied properties differed significantly among themselves. Video-computer method was used to determine the contact surface area for tubers, stones and earth clods with friction surface. The pressure of tested objects on these surfaces were also calculated.
Orthropism of the structure and texture of tuber periderm can result in the fact that the movement of the tuber along a friction face in different directions will cause different friction forces. The aim of the examination was to explain a dependence between the orthropism of potato tubers periderm, and the kinetic value of the coefficient of external friction of tubers against the rubber base. Examinations of measurement of friction force of tubers against the base were done on the test stand equipped with extensometric sensors of force measurement integrated with a microcomputer. Results of examinations confirmed the assumptions that tuber periderm orthropism influences its friction force and therefore the friction coefficient value.
Potato tubers of Ibis and Lawina cultivars frown on midium-heavy soil, as well as the stones and earth clods from the same potato field, were examined for geometrical shape and overall dimensions. Elongation and flattening factors were determined for all examined objects as well as the mass index of overall dimension filling. Values of maximum projection area on the surface for either, potato tubers, stones and earth clods were measured. Significant differences regarding the amounts of examined features among potato tubers and typical impurities of harvested potato crop were observed.
В труде определяли кинетическую энергию почвенных глыб с влажностью 14% образованных на картофельном поле расположенном на среднесвязной почве (29% илистых частиц). Исследовали параметр энергии, при котором глыбы, размельчаются на частицы меньше 0,03 м. Исследования проводились в лабораторных условиях на стенде симулирующем каскады комбайна киносьемочными методами с использованием кинокамеры скорых съемок. Установлено, что почвенные глыбы, особенно фракция крупных глыб несмотря на значительную энергию освобождаемую при ударе в прутовой конвейер размельчаются трудно, что может оказывать отрицательное влияние на работу распределительных механизмов подбирающих машин.
The paper presents results of the studies dealing with evaluation of the horizontal projection of the trajectories of the tubers soiled to various degrees which were fed by rotary elevating drum on the Packman and Peis separators. Process of feeding separators with the crops of two levels of soiling was registered on the film by the Krasnogorsk 16 and Pentaflex AK 16 motion picture cameras and by the stroboscope method using still camera. There has been stated a decreased value of range of the horizontal throw of the tubers soiled at the surfaces in the range 7-11% when compared with the tubers soiled within the range og 1-3%. These differences are statistically significant. The decreased range of the throw of the tubers is the factor which can unfavourably affect uniform distribution of material separated by the separators of the machines harvesting potatoes.
The studies were concerned with distribution of potatoes and soiling fed on the pin conveyors of the separators of the potato combine-harvesters Z 644 and E 667/4 by the rotary elevating drum. There were analysed 90 meters of 16 mm film exposed in the field for each of these combines. The film was taken with the speed of 48 frames per second. Moreover, photostroboscope was used in the laboratory for recording on the single frame the trajectory of falling of potatoes on the pin conveyor of the combine Z 644. The analysis of films and stroboscope photographs was concerned with position of points of falling of tubers and soil clods as well as with so called "relaxation points", i.e. points from which movement of the filmed potato or clod occurs simultaneously with that of the belt of the conveyor. Distribution of points of falling in the case of the combine Z 644 has a central pattern with a slight deviation towards the side which is closer to the cascade. On the other hand, the "relaxation region" for particular components is transfered to the edge of the belt. Similarly, in the case of the range of falling the side closer to the cascade is also prefered when the combine E 667/4 is considered. Moreover, the material is being transfered towards the separator rather on the left-hand-side of the belt, i.e. to the siede which is more distant from the cascade.
Ulepszono własną technikę pomiarów siły tarcia wyposażając stanowisko pomiarowe w mikrokomputer. Potwierdzono występowanie różnic między współczynnikami tarcia kinetycznego bulw i typowych zanieczyszczeń o podłoże. Różnice są istotniejsze na podłożu stalowym.
Static friction coefficients of potato tubers on steel and rubber surfaces were studied as affected by the type of soil on potato field. Three potato cultivars: Jagoda, Lawina and Mila, grown on light and medium-heavy soils, were used for the studies. The angle of tuber friction was measured on an inclined plain. The testing stand was equipped with a photocell and potentiometer connected with a computer for recording and processing the data. The results of tests confirmed research assumptions. It was found that the coefficients of potato tuber friction either, on steel and rubber surfaces, depended on the type of soil.
Определяли параметры движения тел находящихся в массе борозды, переходящих через распределительные механизмы картофелеуборочных комбайнов. В исследованиях применяли метод киносъемок и симулированные тела вводимые искусственно в борозду. Объектами исследований были однорядный комбайн типа 3 644 и двухрядный комбайн типа Э 665/4. Установлено несколько характерных пороков в распределительных механизмах комбайнов и их влияние на производительность работнико! обслуживающих селекционный стол.
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