Patent · US Expired

Card retrieval device

US4190899A · kind A · utility

9Cited by
1References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 10, 1978
Grant dateFeb 26, 1980
Priority date
Expiry dateApr 10, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/04758
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A film card retrieval device for use in an automatic microfilm display apparatus is provided with a switch for sensing that a film card has been retrieved. In the event the device fails to retrieve a film card, the absence of a switch output signal causes the control apparatus to repeat the card retrieval routine.

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