The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 27, 1977
Filed:
Jun. 17, 1976
Applicant:
Inventor:
Robert L Doughty, West Hartford, CT (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
274 / ;
Abstract
A grooved vinyl record disc is securely held in a turntable which includes an annular platen having a rigid, very flat upper surface. Air is evacuated from the underside of the disc, although the platen is impervious to air, by means of annular grooves adjacent the inner and outer edges of the platen and connected through passageways defined in the turntable structure, and through a rotary fluid coupling to communicate with a vacuum source. Resilient seals are provided for isolating the grooves on the underside of the record from ambient air, and these seals support the record disc so it can be flattened as it is drawn downwardly onto the platen by the application of vacuum.