EXPANDABLE WRITING INSTRUMENT

摘要

PURPOSE: Provided is a writing instrument having a new and useful mechanism for expanding the length of a writing instrument barrel while extending a writing tip from a retracted position in the barrel to a writing position. CONSTITUTION: The writing instrument expandable from a compact storage size to a longer, writing size, the writing instrument includes a pen body(40) having a front section(20) with a pen point(60) at one end of the pen body and a second end; a cap slidably mounted to the second end of the pen body, the pen body and cap forming a hollow chamber; a refill cartridge(65) held longitudinally movable within the hollow chamber, the cartridge having a writing tip at one cartridge end; gear unit(70) for longitudinally moving the refill cartridge toward the pen point within the hollow chamber against the spring to extend the writing tip(10) through the pen point to a marking position when the cap is slid away from the pen point on the pen body to an expanded position.