EP0440110A1
Expired / Lapsed
EP
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Ink near-end detecting device
Assignee: Seiko Epson Corp
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Filing: 1991-01-25
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Granted: —
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Expires: 2011-01-25
Abstract
Abstract In an ink near-end detecting device, a pair of electrodes (S₁, S₂) are arranged in the porous material (7) in the ink tank (8) and in the ink pool (12) provided below the ink tank (8), respectively, so that the time instant the ink in the porous material (7) has been nearly used up is detected from the variation of the electrical resistance between the electrodes (S₁, S₂) with the consumption of the ink in the porous material (7).
Inventors
- 👤 Mochizuki Seiji
- 👤 Naka Takahiro
- 👤 Hara Kazuhiko
- 👤 Takagi Akira
- 👤 Hanaoka Yukihiro
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 09:09
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/17; B41J2/175; B41J2/17566; B41J2002/17579
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
120 words
An ink near-end detecting device comprising: means for forming an ink pool (12) communicating with a printing head (3), said ink pool being formed below an ink tank (8) which accomodates a porous material (7) containing an aqueous ink; a pair of electrodes (S₁, S₂) arranged in a part of said porous material (7) and in a part of said ink pool (12), respectively: means for supplying at least one signal representing a predetermined resistance reference value; and resistance change detecting means (16, 17) for detecting the fact that said ink in said ink tank (8) has been nearly used up from a change of the resistance between said electrodes (S₁, S₂) of more than a predetermined reference resistance value.
Claim 2
Dependent Claim
36 words
The ink near-end detecting device as claimed in claim 1, in which said supplying means supplies at least one signal representing a predetermined voltage corresponding to said predetermined resistance reference value which can be changed optionally.
Claim 3
Dependent Claim
81 words
The ink near-end detecting device as claimed in claim 1 or 2, wherein said supplying means comprises means for applying to said resistance variation detecting means a warning set voltage (V₂) corresponding to a change of resistance between said electrodes occurring when said ink has been nearly used up, and means for applying to said resistance variation detecting means a final set voltage (V₁) corresponding to a change of resistance between said electrodes occurring when said ink has been used up.
Claim 4
Dependent Claim
38 words
The ink near-end detecting device as claimed in one of the preceding claims, in which a predetermined voltage corresponding to said predetermined resistance reference value applied to said resistance variation detecting means is changed according to ambient temperature.
Claim 5
Dependent Claim
22 words
The ink near-end detecting device as claimed in claim 4, wherein said resistance variation detecting means comprises a thermistor (R T ).
Claim 6
Dependent Claim
54 words
The ink near-end detecting device as claimed in one of the preceding claims, in which said ink pool (12) has a portion (16) which is smaller in diameter than remaining portions thereof such that said ink pool has an upper chamber (12a) and a lower chamber (12b) on opposite sides of said portion (16).
References Cited (Backward Citations)
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