Patent · US Expired

Record player

US4194743A · kind A · utility

22Cited by
9References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1978
Grant dateMar 25, 1980
Priority date
Expiry dateSep 19, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K29/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In a record player, a turntable is rotatably mounted on a base, and a rotor structure, such as an annular magnet, is mounted on the turntable and cooperates with a stator aperture mounted on the base to cause the turntable to rotate. The annular magnet is preferably a rubber magnet formed by molding rubber mixed with a ferrite powder. For the sake of stability, the annular magnet is in close proximity to the circumference of the turntable. The stator aperture preferably includes bobbins on which stator coils are wound, and arcuate tongues, integral with the base, on which the bobbins are arranged and which form magnetic cores for the stator coils.

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