Tubular writting pen with superposed pressure equalization chambers
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United States of America Patent
Stats
-
Jun 5, 1990
Issued Date -
N/A
app pub date -
Dec 22, 1988
filing date -
Mar 10, 1980
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
Tubular writing pens of the stylographic type, as used by artists and technical draftsmen. Particularly a tubular writing pen having superposed inner and outer ink pressure equalization chambers defined in the cylindrical pen body. A removable outer sleeve complementally engages the cylindrical body of the pen, to cover the outer pressure equalization chamber. A locking surface is defined in the removable sleeve rear edge, so that the sleeve may not be removed accidently with consequent ink loss and damage.
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Family
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Cited Art Landscape
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