Patent · US Expired

Variable speed film transport interlock system

US4933881A · kind A · utility

4Cited by
30References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 13, 1989
Grant dateJun 12, 1990
Priority date
Expiry dateJan 13, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B31/00
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A variable speed film transport interlock control system for allowing a plurality of film audio elements to be run in synchronization with each other with at least one film element running at a different selected speed than the other elements and permitting internal generation of quadrature control signals by an internal microprocessor. The system generates a modified drive signal from a selected standard system drive signal or microcomputer generated signal such that the modified signal corresponds to a speed with a fixed ratio to the speed of the selected unprocessed drive signal under all operating conditions. This permits the modified signal to drive a film transport device, such as a recorder or reproducer, at a different speed than other transport devices while maintaining synchronization with the other devices during forward or reverse, stopping and starting, high speed or low speed operation. In addition, the internal generation of quadrature signals enables the system operator to independently advance or reverse film transport devices to permit searching for a preselected cue point.

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