Knock-out type mechanical pencil with retractable eraser

摘要

A knock-out type mechanical pencil has a supporting rod mounted with an eraser at its rear end and axially slidably engaged within the interior of a cylindrical knock-button. A tubularly cylindrical weight is axially slidably engaged around the supporting rod. A cylindrical magnet is axially magnetized and secured to the inner peripheral surface of the knock-button. An annularly inwardly raised guide portion is formed on the inner peripheral surface of the knock-button for guiding the weight to the axial line of the knock-button when the weight is axially slidably dropped downwardly toward the writing tip of the pencil. To protrude and fix an eraser from the rear end of the tubular cylindrical body, the rear end of the pencil is tilted downward. To automatically contain or retract the eraser in the knock-button, the writing tip of the pencil is directed downwardly in writing state. Thus, this mechanical pencil can stably perform an erasing operation with an eraser without any rocking motion of the eraser in axial direction nor rotation of the eraser.