Torsi Pemotongan dan Efek Hembusan dari Model Pisau Miring (Slanted Blade) untuk Mesin Pemotong Rumput Tipe Rotari

Abstract

Rotary-type mower is commonly used for cutting turfgrass as a part of landscape maintenance. Cutting torque and quality of turf surface resulted by cutting are two important factors that have to be considered in designing rotary-type mower blades. The objectives of this research are to design and build a slanted blade model, and to study its cutting torque, blowing effect, and friction between blades and turf surface on a several rotational speeds, slant angles and blade types. The blade model was tested on a specially designed turf-bin test apparatus. Results of laboratory test on the blade model showed that the cutting torque was influenced by its rotating speed. The biggest cutting torque needed to mow the grass was 0.659 Nm given by the model with slant angle of 15 " with rotating speed of 2800 rpm, and the smallest was 0.073 Nm given by the model with slant angle of 5" with rotating speed of 1960 rpm. The slanted blade model resulted a blowing effect that was able to carry clippings into the collector. Most of the clippings were collected in the collector. The highest collected clippings was 96.94% given by the model with slant angle of 5" and rotating speed of 2800 rpm, and the lowest was 24.76% given by the model and slant angle of 5 O with rotating speed of 2700 rpm. The highest percentage of torque due to friction between blades and turf surface was 40.1 % given by the model with slant angle of 10" and rotating speed of 1960 rpm, and the lowest was 3.9% given by the model with slant angle of 10" and rotating speed of 2800 rpm.