Clock using alternating current cycle counting
US4068465A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 14, 1975 |
| Grant date | Jan 17, 1978 |
| Priority date | — |
| Expiry date | Jul 14, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G19/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a method of keeping time by counting the cycles of an alternating current source and providing both alternating and direct current power from the alternating current source, the direct current power including a variable display voltage for illuminating the lights, displaying time using a plurality of lights and windows corresponding to the lights, generating signals from the alternating current source, counting and dividing the signals, decoding the counted and divided signals, and lighting the lights and windows in accordance with the decoding to display the time of day, and correcting, when necessary, the time displayed by the clock, the improvement comprising providing a plurality of electrical switches corresponding to the lights, the correcting being accomplished by actuating one of the switches, completing an electrical circuit upon such actuation of the switch and comparing the display voltage with the voltage applied to the light whose corresponding switch is actuated, the comparing being operative, whenever the compared voltages are unequal, to alter the counting to correct the time displayed by the clock.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.