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:
Nov. 30, 1999
Filed:
Dec. 18, 1998
Metzeler Schaum GmbH, Memmingen, DE;
Abstract
A foam material element for sound-damping cavities, particularly for light metal extruded profiles used in rail car construction. The foam material element has a foam material sandwich with at least two layers, namely a resilient layer and at least one heavy layer disposed on the resilient layer. The resilient layer is formed of soft foam polyurethane and the heavy layer is formed of a flocculated foam polyurethane compound. Prior to being inserted in a cavity to be sound-proofed, the foam material element is compressed and weld-sealed in an air-tight film. The element is inserted through an opening of the cavity in its compressed condition. After insertion and placement of the foam material element, the film is opened and, as a result of its exposure to air, the foam material element expands to such a degree that at least one heavy layer, biassed by the resilient layer, comes into contact with the walls substantially over a broad surface area.