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:
Oct. 29, 1991
Filed:
Jul. 23, 1990
Otis Elevator Company, Farmington, CT (US);
Abstract
The improvments are applicable to elevator doors and even to doors of vehicles, either made out of two leaves which move in the same direction for the opening and closing thereof, or made out of four leaves each pair of the four leaves opening in the center. The improvements are centered on the use of a single track for both leaves or door panels, a track which may have a rectangular or circular section, located in a box with rolling or movement components which are fastened to the corresponding hanger support of the panel or door. Another improvement consists of the two panels of the door being exactly the same, each one of them including a sound absorbing element. The door frame unit is removable with preassembled active elements so that the same may be transported in a compact, easy manner from the factory to the place of use.