طراحي، ساخت و ارزيابي مكانيزم بسته بردار اتوماتيك بسته هاي يونجه و كاه

چكيده انگليسي :

Design Development and Evaluation of an Automatic Alfalfa Hay and Straw Bale Pick Up Mechanism Samaneh Sadeghzadeh samanehsadeghzadeh@yahoo com April Department of Agriculture Machinery Engineering Isfahan University of Technology Iran Degree M Sc Language Farsi Supervisor J Razavi Jrazavi@cc iut ac ir AbstractAutomatic bale wagon for alfalfa and straw bales are machines which is used in mechanized balegathering and handling operations Several works presented by various researchers were reviewed andfinally the best plan was selected for design fabrication and evaluation In Order to design different unitsand elements of this machine some physical and rheological properties of alfalfa and straw bales weredetermined The coefficients of friction for alfalfa and straw bales on steel wood and concrete surfaces atthree levels of perpendicular loads were determined A confined compression test for determination ofbending strength by the deflection of a two support beam for two levels of moisture content dry and wet based respectively for straw and alfalfa and wet and wet based respectively for straw and alfalfa for alfalfa and straw bales was performed In this study the influenceof the material type modulus of elasticity and required energy was investigated The bale pickup unitcomprises a pair of normally vertical side walls jointed to a rear wall to form a U shaped structure open atits forward end of bale wagon The lower forward extremities of the side walls are provided withdiverging deflector arms which serve to guide the bales into the U shaped frame At the rear of the baleloader an endless conveyor chain is positioned vertically along the rear wall of the framework so thatchain extending around two sprockets on lower and upper shafts Array of lugs or fingers attached onconveyor chain were used in engaging device for lifting bales upwardly The chain is inclined rearwardby an angle of degrees the inclination helping to maintain a bale being elevated in contact with theelevator An electro motor was used to actuate the sprocket for rotation of the conveying chain A baleshoe or holder is pivotally mounted at the forward frame structure which prevents the bales from fallingforward as they are being elevated Because of bale deformation during passage between the walls and atthe same time being pulled upward by the lifting chain compression and stress forces should becompensated for by a guide shoe which at the same time adjusts itself based on the size of the eachparticular bale Solid Works and Cosmos Works software were used for technical modeling drawing andanalysis of designed components After various parts were designed based on mechanical engineeringdesign and considering proper safety factor and standard parts machine was fabricated After fabrication the pick up bale was evaluated over a test rig belt A significant P negative correlation wasfound between length of bales and strength bending r Interaction effect of type and moisturecontent of bales was significant at percent level for bending force Effect of bale and surface type onfrictional coefficient was not significant P however the effect of perpendicular load was verysignificant P A split plot experiment with a completely randomized design was used todetermine effect of picking up speed and type of bale on percent shatter loss and bales apparent quality Results indicated that effect of picking up speed and type of bale did not have a significant difference onexperimental factors so that with an increase or decrease in speed of picking up and in case long or shortlength bales of alfalfa or straw had no effect on percent shatter loss and apparent quality of bales Keywords Alfalfa Automatic Bale Wagon Rheological Properties Pick up Guide shoe

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طراحي، ساخت و ارزيابي مكانيزم بسته بردار اتوماتيك بسته هاي يونجه و كاه

بسته علوفه , خصوصيات مكانيكي , بردارنده , كفشك بسته