円を描くために必要な製図用コンパスに作用させる力の解析

抄録

In the present study, point of application of force, direction of force and severity of force acting on a finger grip in a drawing compasses required for drawing a circle with uniform thickness and dark line on a paper were analyzed. In this paper, as the analytical method, structure and mechanism of the compass were shown, and coordinate system was set in the compass for the analysis. Analytical models based on the set coordinate system were created. There are two cases of ideal force and unideal force acting on the compass in the analytical models. The ideal force acts on the finger grip, and the circle is drawn with the uniform thickness and the dark line on the paper. The unideal force acts on the finger grip, and the circle is drawn with non-uniform thickness and light line on the paper. In analysis results, the experimental tests were conducted about the created analytical models, and the analytical models of appropriateness were checked by comparison between experimental results and analysis results. By use of the analysis results, the impact of drawing the circle with the uniform thickness and the dark line was shown about the point of application of force, the direction of force and the severity of force acting on the finger grip in the compass.