Patent · US Expired

Cartridge

US4525758A · kind A · utility

19Cited by
7References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1982
Grant dateJun 25, 1985
Priority date
Expiry dateJun 16, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B23/0332
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A cartridge to be inserted into a drive unit includes a casing containing a recording medium disc to be driven by the drive unit. The disc has a hub fixed at its center. Center windows are provided at opposite sides of the casing and allow the hub to be inserted therethrough. Head windows are provided also at opposite sides of the casing and allow a reading head to access information recorded on opposite sides of the disc. Shutters are provided around the center windows and normally cover the head windows. These shutters are rotatable about the center windows and uncover the head windows when the cartridge is inserted into the drive unit. An actuator for rotating the shutters is provided between the shutters and the outside of the casing. The actuator has a portion exposed to the outside of the casing so that the shutters are automatically and indirectly rotated by an external force applied to the actuator when the cartridge is inserted into the drive unit. An advantage of the arrangement of these elements is that damage to and malfunctioning of the cartridge is prevented.

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