Filter medium and breather filter structure

• US 8,277,529 B2
• Filed: 08/31/2011
• Issued: 10/02/2012
• Est. Priority Date: 11/05/2004
• Status: Active Grant

• Current Assignee: Donaldson Company Incorporated
• Original Assignee: Donaldson Company Incorporated
• Inventors: Rogers, Robert M., Dema, Keh B.
• Primary Examiner(s): CLEMENTE, ROBERT ARTHUR
• Application Number:
  US13/222,063
• Publication Number:
  US 20110309012A1
• Time in Patent Office: 398 Days
• Field of Search: 554/86, 554/87, 555/27, 555/28
• US Class Current: 55/486
• CPC Class Codes: B01D 2239/0216 Bicomponent or multicomponent fibres
• CPC Class Codes: B01D 2239/065 More than one layer present in the filtering material
• CPC Class Codes: B01D 2239/0668 The layers being joined by heat or melt-bonding
• CPC Class Codes: B01D 2275/10 Multiple layers
• CPC Class Codes: B01D 2279/60 for the intake of internal combustion engines or turbines
• CPC Class Codes: B01D 39/1615 of natural origin
• CPC Class Codes: B01D 39/163 sintered or bonded
• CPC Class Codes: B01D 39/18 the material being cellulose or derivatives thereof cork or peat B01D39/1646 ; making filter paper D21F11/14
• CPC Class Codes: B01D 39/2017 the material being filamentary or fibrous
• CPC Class Codes: B01D 39/2024 otherwise bonded, e.g. by resins
• CPC Class Codes: B01D 39/2037 otherwise bonded
• CPC Class Codes: B01D 46/10 Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces
• CPC Class Codes: B01D 46/2411 Filter cartridges
• CPC Class Codes: B01D 46/521 using folded, pleated material
• CPC Class Codes: B01D 46/71 with pressurised gas, e.g. pulsed air
• CPC Class Codes: Y10T 442/616 Blend of synthetic polymeric and inorganic microfibers
• CPC Class Codes: Y10T 442/622 Microfiber is a composite fiber
• CPC Class Codes: Y10T 442/623 Microfiber is glass
• CPC Class Codes: Y10T 442/637 Including strand or fiber material which is a monofilament composed of two or more polymeric materials in physically distinct relationship [e.g., sheath-core, side-by-side, islands-in-sea, fibrils-in-matrix, etc.] or composed of physical blend of chemically different polymeric materials or a physical blend of a polymeric material and a filler material

Abstract

Thermoplastic bicomponent binder fiber can be combined with other media, fibers and other filtration components to form a thermally bonded filtration media. The filtration media can be used in filter units, such as breather caps. Such filter units can be placed in the stream of a mobile fluid and can remove a particulate and/or fluid mist load from the mobile stream. The unique combination of media fiber, bicomponent binder fiber and other filtration additives and components provide a filtration media having unique properties in filtration applications.

Claims

1. A filter element comprising at least two layer of a nonwoven filter media, the filter element comprising:

(a) a first media layer comprising at least two layers of a first filter medium comprising a first fiber comprising a bicomponent fiber comprising a diameter of 5 to 50 microns, and 5 to 50 wt % of a second fiber, wherein the first filter medium has a pore size of 0.2 to 50 micrometers, a permeability of 2 to 200 ft-min<sup>−

1</sup>, a solidity of about 2 to 25% at 860 Pa and a basis weight of 5 to 1000 g-m<sup>−

2</sup>; and

(b) A second media comprising at least one media layers of a second filter medium that is different from the first filter medium and comprising a pore size of 0.5 to 100 micrometers, a permeability of 5 to 500 ft-min<sup>−

1</sup>, a solidity of about 2 to 25% at 860 Pa and a basis weight of 20 to 120 g-m<sup>−

2</sup>.

2. The filter element of claim 1 comprising three or more layers of the first media layer.

3. The filter element of claim 2 further comprising two or more layers of the second media layer independently comprising a solidity of about 2 to 10% at 860 Pa.

4. The filter element of claim 1 comprising three or more layers of the second media layer.

5. The filter element of claim 1 further comprising the filter element on a support.

6. The filter element of claim 5 wherein the support is perforate.

7. The filter element of claim 1 wherein the bicomponent fiber comprises polyester.

8. The filter element of claim 1 wherein bicomponent fiber comprises nylon.

9. The filter element of claim 1 wherein the second fiber comprises glass.

10. The filter element of claim 1 wherein the second fiber comprises polyester.

11. The filter element of claim 1 wherein the permeability of the first media layer is from about 140 to 460 ft-min⁻

1.

12. The filter element of claim 1 wherein the first media layer comprises a thickness of about 0.05 to 22 millimeter at 860 Pa.

13. The filter element of claim 1 wherein the first media layer comprises a thickness of about 0.5 to 11 millimeter at 860 Pa.

14. The filter element of claim 1 wherein the second media layer comprises a thickness of about 0.3 to 3.6 millimeter at 860 Pa.

15. The filter element of claim 1 wherein one or more filter media comprise a surface treatment agent selected from the group consisting of a silicone, a fluorochemical, an amphoteric molecule, or mixtures thereof.

16. The filter element of claim 1 where the compressibility of the first media layer is about 0.5 to 1 at 860 Pa to 3860 Pa.

17. The filter element of claim 1 where the compressibility of the second media layer is about 0.5 to 1 at 860 Pa to 3860 Pa.

18. The filter element of claim 1 where the compressibility of the first media layer is greater than about 0.7 at 860 Pa to 3860 Pa.

19. The filter element of claim 1 where the compressibility of the second media layer is greater than about 0.7 at 860 Pa to 3860 Pa.