FREE INK SYSTEM

摘要

The present invention relates to a free ink marking instrument (10) for dispensing a fluid. The instrument includes; a passage (60) of reduced capillarity relative to a feeder (46) surrounding the feeder for conveying at least one of fluid and air to the reservoir during an increasing pressure differential between air in the reservoir and the atmosphere, a porous buffer (80) disposed between the wall of the housing and the passage and configured for storing ink during periods of a decreasing pressure differential between air in the reservoir and the atmosphere, a divider tube separating the buffer and the passage along a majority of the length of the buffer. The fluid and air may enter the feeder only through a minor surrounding portion of the buffer during the period of the increasing pressure differential. The present invention also relates to an ink and air conveyor for use in a free ink marking instrument for dispensing ink onto a substrate.