Patent · US Expired

Automatic telephone dialling apparatus

US4081618A · kind A · utility

0Cited by
2References
16Claims
0Family size

Inventor

Key dates

Filing dateSep 13, 1976
Grant dateMar 28, 1978
Priority date
Expiry dateSep 13, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M1/278
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Apparatus for automatically dialling telephone numbers and a card indicative of the number to be called, in which the card is provided with three tracks. The first track is a continuous rectilinear sawtooth track and the second track is parallel thereto and has formed therein cavities, the length of which are indicative of the number to be called. The third track is associated with the second track and is used to stop the card at a particular point. In the apparatus, feelers are provided to co-operate with each track and the card is pushed into the apparatus by a user and will return at a uniform speed. A first feeler can co-operate with the first track to produce a train of impulses only when a second feeler engages in a cavity of the second track, so that the length of the train of impulses is determined by the length of a cavity of the second track. These cavity lengths are indication of the number to be called. The stop provided by the third track and feeler can be used so that the card is stopped until a tone is heard in the earpiece whereupon the user can restart the return movement of the card.

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