US Patent 7097375 Mechanical pencil having a rotatable wheel for advancing lead

A mechanical pencil is described. The mechanical pencil includes a grip barrel with a slide member to hold a piece of lead. A wheel is rotatably mounted in the grip barrel around a wheel axis, such that a portion of the wheel extends through and beyond an opening in the grip barrel. A gear is attached with the wheel for sliding the slide member that is slide-ably disposed within the grip barrel. A chuck is connected with the slide member such that a user may roll the wheel to force the chuck to push lead from the lead chamber and out of the grip barrel, thereby allowing the user to control advancement of the lead from the mechanical pencil.