Retractable marking pen includes annular seal in replaceable seal holder unit that acts to seal the marking tip of the replaceable marking unit from the barrel opening when the tip is in the retracted position

摘要

The pen includes a barrel (2) within which a marking unit (1), that includes a marking tip (5) and a marking fluid reservoir, is replaceably disposed so that the tip can be advanced or retracted by a retraction mechanism. A replaceable annular seal (8) is positioned within a replaceable seal holder (11) or in the marking unit that closes off the retracted marking tip from the barrel opening (6) when the marking unit is in the retracted position. The seal is received in a cavity (12) in the seal holder and arranged to roll between the seal holder and the marking tip during movement of the marking tip between the writing and retracted positions, with the seal holder including an end wall (13) that limits the movement of the seal within the barrel. An Independent claim is included for a refill unit for a marking instrument.