Patent · US Expired

Lighted telephone

US5029205A · kind A · utility

8Cited by
19References
5Claims
0Family size

Inventor

Key dates

Filing dateNov 30, 1989
Grant dateJul 2, 1991
Priority date
Expiry dateNov 30, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S362/802
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A telephone handset that has a light bulb disposed on it has a special switch that allows the light to automatically illuminate upon using the phone. The switch changes from an open position to a closed one upon a change in the orientation of gravity. One embodiment of the switch includes a hollow chamber having two separate contact plates disposed at one end and a freely sliding conductive manner that comes into contact with the contacts upon picking up the phone. A second switch embodiment includes three parallel pins with a central one the pins having a hanging pivoting member that serves to contact one of the other pins upon a change in gravitational orientation. Also included is a removable socket member to facilitate replacement of the bulb.

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