Relationship between the Shape of Cutting Attachment Guards and Operating Efficiency for Portable Brush Cutters

Abstract

We studied the dimensional requirements of the cutting attachment guard to improve the protection performance for thrown items on the basis of the results (Tsukamoto et al., 2013a, 2013b) obtained for the direction of items thrown from the brush cutters. We measured the engine speed, the shaft speed, and the operating efficiency for three types of cutting attachment guards. We fabricated two types of prototype guards. Both prototype guards tend to improve the operating efficiency compared to the normal guard. Findings were obtained for the size criteria of the guard that can improve both the operating efficiency and the protection performance.