US3772910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Precision viscometer timer control system
Assignee: United States Department of the Air Force
•
Filing: 1971-12-22
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Granted: 1973-11-20
•
Expires: 1991-12-22
Abstract
Abstract A precision viscometer timer control system where a pair of spaced coils surround a precision tube, so that as a metal ball passes through the coil the inductance is changed causing an oscillator circuit to react, influencing a switching circuit thereby automatically starting and stopping a connected timer.
Inventors
- 👤 J Mcginn
- 👤 T Dellecave
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:44
CPC Classifications
G; G01; G01N; G01N11/00; G01N11/10; G01N11/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
177 words
A precision viscometer timer control system comprising: a falling ball viscometer, including a support means, a precision tube mounted in the support means, a metal ball and a ball release means positioned above the tube; a timing means; a timing control circuit connecting the timing means to the said viscometer including a first and second sensing coil, an oscillator circuit comprising, a first transister having a base, emitter and collector, a resistor and capacitor connected in parallel to the base of said transistor, a Zenner diode resistively connected between a power supply and the emitter of the transistor, a capacitor connected between the collector and emitter of the transistor, a capacitor connected between the input signal line and said emitter, and an inductor connected between the collector and base of said transistor through said parallel connected resistor and capacitor for producing a known signal in the first and second coils and sensing a change in said signal; a detecting circuit and a switching circuit which when combined with the oscillating circuit engage and disengage the time means.
Claim 2
Dependent Claim
177 words
A precision viscometer timer control system comprising: a falling ball viscometer, including a support means, a precision tube mounted in the support means, a metal ball and a ball release means positioned above the tube; a timing means; a timing control circuit connecting the timing means to the said viscometer including a first and second sensing coil, an oscillator circuit comprising, a first transister having a base, emitter and collector, a resistor and capacitor connected in parallel to the base of said transistor, a Zenner diode resistively connected between a power supply and the emitter of the transistor, a capacitor connected between the collector and emitter of the transistor, a capacitor connected between the input signal line and said emitter, and an inductor connected between the collector and base of said transistor through said parallel connected resistor and capacitor for producing a known signal in the first and second coils and sensing a change in said signal; a detecting circuit and a switching circuit which when combined with the oscillating circuit engage and disengage the time means.
Claim 3
Dependent Claim
53 words
A circuit according to claim 1 comprising: a second transistor having a base, emitter and collector and having its base connected to the emitter of said first transistor and further having its collector resistively connected to a power supply and the emitter of said transistor connected to the anode of the Zenner diode.
Claim 4
Dependent Claim
96 words
A switching circuit according to claim 2 comprising: a third transistor with a base, emitter and collector, having its base connected to a detector output, collector resistively connected to a power supply and emitter to the Zener Diode anode; a first silicon controlled rectifier having its cathode connected to a power supply through a parallel resistance-capacitance circuit to the collector of said third transistor; and a second silicon controlled rectifier connected through a resistance-capacitance circuit to said first silicon controlled rectifier and a capacitive connection between the anode of said first and second silicon controlled rectifiers.
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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) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |