Telescopic ball-point pen

A telescopic ball-point pen comprising a front case and a rear case capable of being slidably engaged in the front case and the rear case can be adjusted to make a telescopic motion to reach respective steps;

• wherein the front case comprises a front case body made of synthetic resin, a mouth ring which is screwed onto the front case body, a cylindrical member provided inside the front case body and made of synthetic resin, and extended inside a rear case body, a telescopic ball-point pen refill capable of detachably inserting into the cylindrical member and protruding a tip of the telescopic ball-point pen refill from the mouth ring, a slidable tip fitting capable of protruding to a position where the tip of the telescopic ball-point pen refill can be concealed against a coil spring provided between the telescopic ball-point pen refill and the mouth ring a short rod-like member which contacts the slidable tip fitting at its tip which is freely movable inside a through hole of a fixed pedestal of the cylindrical member so as to press the slidable tip fitting against a spring force of the coil spring, and an engaging concave and made of synthetic resin and fixed to a base end of the cylindrical member and engaging with an engaging convex of a rear case head cap;
• wherein the slidable tip fitting is divided into a concealing portion and a sliding portion having a collar which diameter is larger than an inner diameter of the mouth ring, and wherein a step formed at a joint between the concealing portion and the sliding portion can engage with an inner step of the mouth ring, and the coil spring is charged in a space formed by the end of the mouth ring and the collar;
• and
• wherein the rear case comprises the rear case body made of synthetic resin which is pushed into the front case body to press the short rod-like member and the rear case head cap having the engaging convex made of synthetic resin which can be engaged in or disengaged from the engaging concave, wherein the rear case can press the short rod-like member and slidable tip fitting when the rear case body is pushed into the front case body, while the engaging convex of the rear case head cap can be engaged in the engaging concave of the front case body at the position where the rear case body is pushed into the front case body.