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. 14, 2000
Filed:
Mar. 30, 1998
Anthony Hollingsworth, Birkenau, DE;
Peter Pfeuffer, Ketsch, DE;
Jorg Sievert, Weinheim, DE;
Thomas Schroth, Bobenheim, DE;
Antje Rudolph, Unterflockenbach, DE;
Firma Carl Freudenberg, Weinheim, DE;
Abstract
A cartridge filter having a cylindrical filter element, which is pleated parallel to its axis and is made of a layered non-woven unitary fabric. The fabric is permeable by air flow in the radial direction and is used in fresh air-supply filtration with initial pressure losses of less than 300 Pa at air flow rates through the filter medium of less than 250 m.sup.3 /m.sup.2 h. The non-woven fabric has a mass per unit area of 100 to 500 g/m.sup.2, and a thickness of 1.5-7.0 mm mm. It is made of layered staple fibers of a titer of 0.1 to 50 decitex, which are bonded by a thermally softened binding agent. A bottom layer bordering on the downstream side is contained in the non-woven fabric, having a thickness of 10 to 60% of the overall thickness, and is compressed two to ten times as much as a top layer bordering on the upstream flow side having a thickness of 10-60% of the overall thickness. One or more intermediate layers link the top and bottom layers to one another. The fabric is unitary in structure, in that it is not a composite formed of separate layers which must be subsequently joined together.