Invalidity dossier
US 6502933
Ink cartridge for ink jet printer
Current assignee: S Printing Solution Co Ltd
Added 9/23/2026, 9:10:33 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6,502,933 B2
Title: Ink cartridge for ink jet printer
Inventors: Dae-soon Lim; Jae-ho Moon; Jeong-seon Kim
Original assignee: Samsung Electronics Co., Ltd.
Application: US 09/761,841, filed 2001-01-18
Priority date: 2000-11-06
Granted / published: 2003-01-07
Source: https://patents.google.com/patent/US6502933/en
Purpose. The cartridge addresses waste and user uncertainty in conventional ink cartridges, where a sponge occupies nearly all the internal space so the cartridge must be replaced even with substantial ink remaining, and where no means exists for the user to know when replacement is due.
Plain-language scope. The cartridge has an ink storing portion plus a head that ejects ink droplets. The ink storing portion includes: (1) a chamber holding ink in a liquid state rather than absorbed in a porous medium; (2) a negative pressure maintaining means keeping chamber pressure negative, comprising a first sponge in an accommodating portion with a through hole, and a screw pressing the sponge toward the hole, so adjusting screw pressure adjusts the negative pressure; (3) a uniform supply guide means between chamber and head, comprising a second sponge in the ink exhaust path that absorbs ink and supplies it uniformly to the head; and (4) a detecting means with a Styrofoam float carrying a magnet, a guide plate, and a proximity sensor that signals when ink is nearly consumed. A cover with rubber portions permits ink injection by needle; a filter (installed inside the chamber or inserted from outside) removes impurities and bubbles. Because ink flows freely rather than being held in a sponge, most stored ink can be used for printing.
What the excerpt does not establish. It does not provide the full claim set or claim language, the complete written description, or the drawings' contents. It does not establish prosecution history, the exhaustive prior-art references relied upon, validity, enforceability, or the current legal status beyond the listed "Expired – Fee Related" notation. It does not detail the three-color (yellow, magenta, cyan) embodiment beyond noting three ink storing portions of like structure. Numerical dimensions, materials, and manufacturing methods are not given.
Generated 10/1/2026, 9:40:55 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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