US3878459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic field detection method for determining whether apparatus is properly grounded
Assignee: Individual
•
Filing: 1972-05-05
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Granted: 1975-04-15
•
Expires: 1992-05-05
Abstract
Abstract A personal electrostatic safety monitor comprising an electronic circuit which continuously monitors electrostatic energy and similar forms of electrical energy for the purpose of human safety. The electronic circuit employs lights, buzzers or other suitable alerting devices to provide personnel with a warning of conditions which create a hazard or nuisance with regard to static electricity or other forms of electrical energy.
Inventors
- 👤 Harry A Hanna
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:15
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/145; G01R27/00; G01R27/02; G01R27/20; G01R29/00; G01R29/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
184 words
The method of detecting the grounded condition of electric or electronic equipment or apparatus enclosed by a conduction body by detecting the presence of a low voltage alternating electrostatic field radiating from the conductive body housing the equipment or apparatus comprising the steps of: placing an induction plate means adjacent the conductive body within the alternating electrostatic field, if present, capacitively coupling the induction plate means to a preamplifier stage, preamplifying the input signal and supplying the preamplified signal to a driven stage, and connecting a signal emitting means to said driver stage to indicate the detection of the field, the degree of capacitive coupling of said preamplifier stage to the induction plate means and the size and position of said induction plate means with respect to the remainder of said circuit being such that the circuit is activated at a low voltage value, and determining from the detection of said field and the energizing or nonenergizing of the signal emitting means if the conductive enclosure is properly grounded, energization of said signal emitting means indicating that the conductive enclosure is not properly grounded.
Claim 2
Independent Claim
184 words
The method of detecting the grounded condition of electric or electronic equipment or apparatus enclosed by a conduction body by detecting the presence of a low voltage alternating electrostatic field radiating from the conductive body housing the equipment or apparatus comprising the steps of: placing an induction plate means adjacent the conductive body within the alternating electrostatic field, if present, capacitively coupling the induction plate means to a preamplifier stage, preamplifying the input signal and supplying the preamplified signal to a driven stage, and connecting a signal emitting means to said driver stage to indicate the detection of the field, the degree of capacitive coupling of said preamplifier stage to the induction plate means and the size and position of said induction plate means with respect to the remainder of said circuit being such that the circuit is activated at a low voltage value, and determining from the detection of said field and the energizing or nonenergizing of the signal emitting means if the conductive enclosure is properly grounded, energization of said signal emitting means indicating that the conductive enclosure is not properly grounded.
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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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |