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:
Jun. 03, 2003
Filed:
Oct. 31, 2000
Michael G. Dykhoff, Maplewood, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A fire stopping device includes a containment shell with a heat rupturable element and an intumescent filler material arranged in the containment shell. The containment shell is formed of a fire resistant material capable of containing the intumescent material after the rupturable element fails. In addition, the heat rupturable element is designed to fail at a force which is lower than the intumescent filler material expansion force. In this manner, when the intumescent filler material reaches its activation temperature, it expands with a force greater than the strength of the rupture element, thereby causing the rupture element to fail. Thus, expansion of the intumescent filler material takes place in a controlled manner via the rupture element.