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:
Jan. 10, 1978
Filed:
Feb. 28, 1977
Robert Louis Beranek, Jr, Johnson, TX (US);
Donny Lee Timms, Johnson, TX (US);
Johns-Manville Corporation, Denver, CO (US);
Abstract
Disclosed is a method and apparatus for making a board-like product capable of being formed into a duct section having a male end and a female end for joining sections together to form a duct. Inorganic fibers coated with a heat setable binder and collected in the form of a blanket are passed between heated moving surfaces to cure the binder in the top and bottom surface portions. The resultant partially cured blanket is then passed between one or more sets of heated platens to completely cure the binder and to shape the blanket to the desired thickness and configuration. A flat valley depression is formed longitudinally along the blanket down its center portion, and each edge is provided with a male edge, in the first set of platens. After the blanket has been shaped and cured, it is separated into two strips along the middle portion of the flat valley to form two strips, each having a female edge along one longitudinal edge and a male edge along the opposite edge. The method and apparatus of the present invention provides an improved female edge, i.e., one having a much smaller radius than produced in the prior art process and capable of forming better joints in air duct systems.