抄録
Properties of acoustic emission (AE) signals detected by the sensor attached on a ruler for the mechanical drawing was discussed in order to evaluate the tone of lines drawn with a mechanical pencil. In the case of drawing uneven tone lines, envelope signals of the sensor on the ruler show the trends that are similar to the signals detected by the sensor on the backside of the drawing board and the bottom of the pencil holder. It was found that AE waves caused by wear of the pencil lead associated with drawing lines are propagated to the sensor through the side of the ruler so that this method is applicable in the case of drawing along the ruler. Since no limitation of the area for appropriate evaluation and convenience for handling the pencil, attaching the sensor on the ruler is suitable to evaluate the tone of lines drawn with the pencil.