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:
Sep. 27, 1983
Filed:
Feb. 04, 1982
William C Shaw, Streetsville, CA;
Imax Systems Corporation, Toronto, CA;
Abstract
A projection screen assembly is disclosed. The assembly includes a screen which can be lifted into an extended position or lowered into a collapsed configuration for permitting a building in which the screen is installed to be used for other purposes. Lifting means is provided for raising the screen and tensioning it in the vertical direction. Lateral tensioning is effected simultaneously by tensioning elements disposed one adjacent each side edge of the screen. The tensioning elements are coupled to the screen by lateral tensioning members which are of progressively decreasing length in directions extending inwardly from the upper and lower margins of the screen so that the tensioning elements adopt the shape of caternary curves. When the screen is tensioned vertically, these curves are flattened so that the screen is tensioned laterally by the lateral tensioning members.