Patent · US Expired

Head drum forming an air film between an outer surface thereof and a tape medium

US5041937A · kind A · utility

10Cited by
2References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 15, 1990
Grant dateAug 20, 1991
Priority date
Expiry dateFeb 15, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B15/64
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A head drum for a recording and/or reproducing apparatus is provided. The head drum includes a rotary drum, a stationary drum, and a plurality of magnetic heads for recording and/or reproducing signals on a magnetic tape. A chamber is provided which includes a first circumferentially extending recessed portion formed on the rotary drum and a second circumferentially extending recessed portion formed in the stationary drum. A plurality of grooves are formed in a surface of the rotary drum which communicates between the chamber and the exterior of the head drum. In a first embodiment, the second recessed portion is eccentrically arranged to extend closer to a first position on an exterior surface of the head drum where the magnetic tape starts to wrap about the head drum than at a second position on said exterior surface. In an alternative embodiment, the second circular recessed portion has a greater depth from the first circular recessed portion at the first position than at the second position. The recesses are provided to form a uniform air film between the magnetic tape and the head drum in cooperation with circumambient air introduced therebetween.

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