Writing instrument

A writing instrument, comprising a rigid barrel defined by a rigid tubular lower barrel portion having an open lower end and a rigid tubular upper barrel portion removably mounted on said lower barrel portion and having a closed upper end, a rigid elongated ink cartridge located in said barrel and having a writing point that is extendible through the open lower end of said lower barrel portion, operating means located in said barrel for alternately urging said cartridge downwardly and upwardly to propel the writing point through the open end of said lower barrel portion to an exposed writing position thereof and to retract said cartridge for moving the writing point to an inactive position thereof, wherein said writing point is withdrawn within the open lower end of said lower barrel portion, a pair of openings formed in said lower barrel portion in opposed relation, said operating means including an actuating member located in said lower barrel portion and underlying said openings therein, said actuating member having a pair of opposed arms which are rearwardly tapered on the inner surfaces thereof, and a rearwardly tapered rigid driver member rigidly connected to said cartridge and located adjacent to said actuating member in alignment with said openings, the rearward tapers of the inner surfaces of said arms corresponding to the tapered configuration of said driver member, wherein an inward pressure on said actuating member by a force directed thereto through said openings causes relative sliding movement between said actuating member and said driver member with the inner surfaces of said actuating member traveling along the outer surface of said driver member as a result of the tapered configurations thereof to thereby cause said actuating member in cooperation with said operating means to exert a longitudinal force on said driver member to move said driver member and said cartridge with which it is interengaged in a longitudinal direction to cause direct positive movement of the writing point of said instrument through the open end of said lower barrel portion to the exposed writing position thereof, or to retract the writing point to the inactive position thereof, said actuating member having an upper tubular portion to which are joined said downwardly extending opposed arms on the outer surfaces of which pads are located, said arms being free at the lower ends thereof and having flexing movement relative to said upper tubular portion, and said pads being received in the openings in said lower barrel portion, wherein an inward force on said pads causes said arms to flex inwardly against said tapered driver member to force the driver member in the longitudinal direction thereof.