US4183029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ink filter clogging sensor and indicator
Assignee: Ricoh Co Ltd
•
Filing: 1978-08-21
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Granted: 1980-01-08
•
Expires: 1998-08-21
Abstract
Abstract An ink filter (15) is provided in an ink supply conduit (12). First and second electrodes (21), (22) are disposed in the conduit (12) upstream and downstream of the filter (15) respectively. A sensor means (23), (24), (27), (28), (32) measures an electrical parameter such as the electrical resistance, capacitance or the like between the electrodes (21), (22) which varies as a function of the degree of clogging of the filter (15). An indicator (34) such as a light or lights (36), analog meter (33) or the like indicates the magnitude of the electrical parameter and thereby whether the filter (15) is clogged or unclogged.
Inventors
- 👤 Takuro Isayama
- 👤 Takao Fukazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:56
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/17; B41J2/175; B41J2/17563; B01; B01D; B01D35/00; B01D35/14; B01D35/143; G; G01; G01D; G01D15/00; G01D15/16; G01D15/18
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
62 words
In an ink jet printing apparatus having an ink supply conduit and an ink filter provided in the conduit, the combination characterized by comprising: a first electrode provided in the conduit upstream of the filter; a second electrode provided in the conduit downstream of the filter; and sensor means connected to the first and second electrodes for sensing an electrical parameter therebetween.
Claim 2
Dependent Claim
62 words
In an ink jet printing apparatus having an ink supply conduit and an ink filter provided in the conduit, the combination characterized by comprising: a first electrode provided in the conduit upstream of the filter; a second electrode provided in the conduit downstream of the filter; and sensor means connected to the first and second electrodes for sensing an electrical parameter therebetween.
Claim 3
Dependent Claim
15 words
An apparatus as in claim 1, in which the electrical parameter is an electrical capacitance.
Claim 4
Dependent Claim
16 words
An apparatus as in claim 1, further comprising an analog indicator for indicating the electrical parameter.
Claim 5
Dependent Claim
15 words
An apparatus as in claim 1, in which the electrical parameter is an electrical resistance.
Claim 6
Dependent Claim
15 words
An apparatus as in claim 4, in which the sensor means comprises a resistance bridge.
Claim 7
Dependent Claim
28 words
An apparatus as in claim 1, further comprising indicator means connected to the sensor means for indicating whether the electrical parameter is above or below a predetermined value.
Claim 8
Dependent Claim
14 words
An appartus as in claim 6, in which the indicator means comprises a light.
Claim 9
Dependent Claim
51 words
An apparatus as in claim 1, further comprising indicator means connected to the sensor means for indicating whether the electrical parameter is below a first predetermined value, between the first predetermined value and a second predetermined value which is higher than the first predetermined value or above the second predetermined value.
Claim 10
Dependent Claim
13 words
An apparatus as in claim 8, in which the indicator means comprises lights.
Claim 11
Dependent Claim
37 words
An apparatus as in claim 8, in which the indicator means comprises first and second comparators having reference levels set to the first and second predetermined values respectively and decoder means for decoding outputs of the comparators.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-07 | 1983-07-09 | 1984-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-07 | 1987-07-09 | 1988-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-07 | 1991-07-09 | 1992-01-08 | $7700.00 | Window Closed / Lapsed |