Patent · US Expired

World clock with synchronous display

US6275449A · kind A · utility

29Cited by
19References
6Claims
0Family size

Inventor

Key dates

Filing dateAug 7, 1998
Grant dateAug 14, 2001
Priority date
Expiry dateAug 7, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG04B19/228
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A world clock includes a map with markings arranged to indicate time zones for actual geographic locations and a single-row table having 24 columns for correlating the markings with hour markings on a belt. The belt is driven by a controller to move one column every hour, with stoppage of the belt below the next column being controlled by a light sensor arranged to sense blank spaces on the belt between the hour markings.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.