Abstract: A mechanical pencil incrementally rotates a lead by operation of a touch button. The pencil has a barrel in which is disposed a holder. A rotatable pipe having a writing mechanism assembly incorporated therein is attached rotatably to the holder. Around the periphery of the holder, a slide member is disposed to undergo forward and rearward movement, and the slide member is moved forward by pressing the touch button disposed on the barrel. The holder houses a sleeve which is moved forward by the slide member and which turns in a circumferential direction. A rotation-transmitting cam face is provided on each of a front end face of the sleeve and a rear end face of the rotatable pipe. By the forward movement of the sleeve, the cam faces are engaged with each other to incrementally rotate the rotatable pipe, whereby the lead is incrementally rotated.

Abstract: A mechanical pencil incrementally rotates a lead by operation of a touch button. The pencil has a barrel in which is disposed a holder. A rotatable pipe having a writing mechanism assembly incorporated therein is attached rotatably to the holder. Around the periphery of the holder, a slide member is disposed to undergo forward and rearward movement, and the slide member is moved forward by pressing the touch button disposed on the barrel. The holder houses a sleeve which is moved forward by the slide member and which turns in a circumferential direction. A rotation-transmitting cam face is provided on each of a front end face of the sleeve and a rear end face of the rotatable pipe. By the forward movement of the sleeve, the cam faces are engaged with each other to incrementally rotate the rotatable pipe, whereby the lead is incrementally rotated.