Cartridge filter

US6146436A · kind A · utility

Assignee

• Firma Carl Freudenberg · DE

Inventors

• Anthony Hollingsworth · Birkenau, DE
• Peter Pfeuffer · Ketsch, DE
• Jorg Sievert · Weinheim, DE
• Thomas Schroth · Worms, DE
• Antje Rudolph

Key dates

• Filing date: Mar 30, 1998
• Grant date: Nov 14, 2000
• Expiry date: Mar 30, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D2279/50
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

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.