Development and Performance Evaluation of Coconut Dehusking Machine (original) (raw)

-Contrary to the immense economic importance of coconut for both industrial and domestic uses, dehusking of the fruits after harvesting constitutes the most difficult and dangerous operations during processing. Performance evaluation of coconut dehusking machine was carried out. The machine was designed and fabricated using locally sourced materials. It consists of the supporting frame where the machine components were mounted. The de-husking unit consists of two galvanized steel pipe rollers with spikes and shafts. The driving and driven roller shafts are mild steel rods supported at both ends by ball bearings. Six spur gears were used with various pitch circle diameters and number of teeth respectively, and were attached proportionally to the driving and driven roller based on their functions in the machine. The flywheel is driven by a pinion which is attached to pulley and connected with a V-belt to the pulley of the electric motor, and rotates at the same speed with the driving gear. Two middle gears mounted on the same shaft with the flywheel were also incorporated to produce high torque. When the motor is switch on, power is transmitted through the gearing arrangement to the rollers with plurality of spikes and rotate them in opposite directions towards the center there by causing both the gripping and tearing of the husk when coconut is placed in between the rollers. While the rollers rotate, a feeding clamp welded to the frame is used to feed coconut fruit in the de-husking unit and a spring is attached to enable relative motion between the coconut fruit and the rollers during de-husking. Different sizes of coconut fruits were loaded at different times on the machine and the time taken for each fruit to be dehusked was recorded. A total of 80 fresh nuts were tested. The performance evaluation shows that the average efficiency of the machine was 92.50% while the average capacity is 120.6 coconuts per hour. On the other hand, the percentage number of distorted and broken coconuts were 7.5% and 3.75%. These figures are however infinitesimal Compare to the existing coconut dehusking machines. Hence it is recommended for use by farmers.