Circuit for detecting firing of an ultraviolet radiation detector tube
US5194728A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 5, 1991 |
| Grant date | Mar 16, 1993 |
| Priority date | — |
| Expiry date | Dec 5, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23N5/082
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A driver circuit for an ultraviolet detector (UV) tube discriminates between firing of the UV tube in response to ultraviolet radiation impinging on it and a high resistance short between its output terminals. A capacitor charged on half cycles of AC power applied to the circuit discharges partially when the UV tube fires. This charge is transferred to a second capacitor to create a voltage displaced from ground. Each time the UV tube fires, the steep wave front generated thereby is passed by a high pass filter to a switch which momentarily grounds the voltage on the second capacitor through a resistor. The rapid change in the switch element's voltage signifies the presence of ultraviolet radiation on the UV tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.