Kinematic Analysis of the Drive Mechanism for the Crank of the Movable Working Body in a Garden Milling Machine

Abstract

This study presents a kinematic analysis of the crank­driven mechanism powering the movable working body of a garden milling machine used for inter­trunk and near­trunk soil cultivation. The aim is to enhance the quality of inter­trunk tillage by minimizing the unprocessed area between the tillage cutter and the protected zone around tree trunks. The object of the study is a garden milling machine developed at the Scientific Department of Livestock and Fodder Production Mechanization, Research Institute of the Armenian National Agrarian University. The machine›s control system enables the hydraulic cylinder piston to be fixed not only at the end positions but also at intermediate points while maneuvering around tree trunks. A kinematic diagram of the mechanism was developed, and the trajectories of the cutter’s center of rotation were determined for both full and partial piston strokes. Relevant calculation formulas were derived, and the variations in unprocessed areas were analyzed in both scenarios. Additionally, the work efficiency coefficient (K) was calculated based on the combined radius of the tree trunk and its protective zone (r_ծ + b). The analysis revealed that fixing the piston in intermediate positions significantly reduces the unprocessed area compared to using the full piston stroke. Furthermore, as the combined value of (r_ծ + b) decreases, the efficiency coefficient K increases, reaching a maximum of 83.7 % at a minimum value of (r_ծ + b) = 7 cm.