Patent · US Expired

Shock preventing telephone handset for paystation

US5418851A · kind A · utility

0Cited by
2References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 31, 1994
Grant dateMay 23, 1995
Priority date
Expiry dateMar 31, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M1/18
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Shock prevention elements for use in a telephone paystation handset consisting of a pair of polyester dielectric elements positioned over associated transmitter and receiver units so as to block high voltage potentials resulting from application of collect and refund signals applied to the paystation from an associated telephone central office.

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