Micro Co., Ltd.

Tomohiro Hosoya

Hiroyuki Kanari

Akihiro Ohkouchi

A knocking-type writing instrument has a writing refill, such as a pencil lead or an ink cartridge, that is advanced by knocking a knocking member, and an eraser held by an eraser holder disposed at a rear part of the knocking member. When the writing instrument is inclined so that the eraser side faces downward, a control pin provided in the eraser holder and a movable stopper drop by their own weights along a sliding groove of the knocking member. When the control pin drops a predetermined distance and enters a circumferential locking groove provided at a rear end of the sliding groove, detachment of the control pin is prevented by the stopper, and the eraser holder is unable to retract to the inside of the knocking member. In this state, a radial projection on the control pin abuts a rear end face of the knocking holder, whereby the knocking member is locked and can no longer be knocked, and feeding of the writing refill is prevented.

Knocking-type writing instrument equipped with eraser

A rotary feeding mechanism for axially feeding a rod-shaped body from a main body by rotating a tapered tip has a simple structure and can be produced economically. The main body is provided with plural open windows are arranged at a predetermined thread pitch along an axial direction of the main body. The tapered tip is installed rotatably on the main body, and a guide pipe extending toward the inside of the main body is fixed to the tapered tip. A holder for holding the rod-shaped body is housed in the main body, and the holder and the guide pipe are connected non-rotatably and movably in the axial direction. The outer periphery of the holder has an external thread which engages with the windows so that when the tapered tip is rotated, the holder moves in the axial direction while rotating via the guide pipe, and the rod-shaped body can be projected from or retracted into the main body.

Rotary feeding mechanism for rod-shaped body

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.

Growing community of inventors

Fukushima-ken, Japan

Tomohiro Hosoya