US4139816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copy paper test apparatus
Assignee: PRINCETON ELECTRO DYNAMICS Inc
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Filing: 1977-12-15
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Granted: 1979-02-13
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Expires: 1997-12-15
Abstract
Abstract Test apparatus which indicates the peak potential to which copy paper is charged, the surface potential remaining after a dark decay interval, and the potential remaining after a light exposure interval.
Inventors
- 👤 Robert F. Sanford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:38
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/75; G01; G01R; G01R19/00; G01R19/04; G01R29/00; G01R29/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
109 words
In test equipment for analyzing the surface potential of coated light sensitive materials, apparatus comprising: a head for holding said materials in place; first means for rotating said head; second means for charging said materials at a predetermined current and for a predetermined interval of time; third means responsive to the rotations of said head for detecting the potential stored on said materials at any given instant of time; a source of light illumination; and fourth means for regulating the interval of current charging, an interval of light exposure illuminating said light sensitive materials and the time at which the potential stored on said materials is detected for analysis.
Claim 2
Dependent Claim
109 words
In test equipment for analyzing the surface potential of coated light sensitive materials, apparatus comprising: a head for holding said materials in place; first means for rotating said head; second means for charging said materials at a predetermined current and for a predetermined interval of time; third means responsive to the rotations of said head for detecting the potential stored on said materials at any given instant of time; a source of light illumination; and fourth means for regulating the interval of current charging, an interval of light exposure illuminating said light sensitive materials and the time at which the potential stored on said materials is detected for analysis.
Claim 3
Dependent Claim
58 words
The apparatus of claim 1 wherein there is also included a source of timing control signals and wherein said fourth means pre-programs said control signal source to automatically regulate the interval of current charging, the interval of light exposure illuminating said sensitive materials and the instant of time at which the stored potential on said materials is detected.
Claim 4
Dependent Claim
23 words
The apparatus of claim 1 wherein fifth means are included to display the potential stored on said materials as a function of time.
Claim 5
Dependent Claim
42 words
The apparatus of claim 3 wherein said fifth means includes a voltmeter and a chart recorder, and wherein sixth means are included to provide a full scale deflection on said meter for calibrating said recorder prior to analysis of the potential detected.
Claim 6
Dependent Claim
28 words
The apparatus of claim 3 wherein said fifth means includes a voltmeter and an output signal source providing control signals effective to energize an X-Y plotter into operation.
Claim 7
Dependent Claim
69 words
The apparatus of claim 2 wherein said fourth means also pre-programs said control signal source to establish a time lapse between the intervals of current charging and light exposure illumination, and wherein said fourth means additionally pre-programs said control signal source to provide detections of the potential stored on said light sensitive materials upon conclusion of the current charging interval, the intervening interval, and the light exposure illumination interval.
Claim 8
Dependent Claim
48 words
The apparatus of claim 6 wherein said coated light sensituve material comprises electrostatic copy paper, and wherein said second means charges said electrostatic copy paper at a current substantially equal to the current charging said paper when in a copier machine in which it is intended for use.
Claim 9
Dependent Claim
38 words
The apparatus of claim 7 wherein said fourth means pre-programs said current charging and light exposure illumination intervals at intervals substantially equal to the current charging and light exposure intervals for said paper when in said copier machine.
Claim 10
Dependent Claim
28 words
The apparatus of claim 8 wherein said fourth means also programs said intervening interval substantially equal to the dark decay interval for said paper when in said machine.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-12 | 1982-08-14 | 1983-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-12 | 1986-08-14 | 1987-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-12 | 1990-08-14 | 1991-02-13 | $7700.00 | Window Closed / Lapsed |