Filter assembly with pleated media V-packs, and methods

• US 7,311,747 B2
• Filed: 10/14/2004
• Issued: 12/25/2007
• Est. Priority Date: 10/14/2003
• Status: Expired due to Fees

• Current Assignee: Donaldson Company Incorporated
• Original Assignee: Donaldson Company Incorporated
• Inventors: Adamek, Daniel Eric, Gustafson, Michael Jon, Mills, Jarren B., Schnieder, Kirk A., Welch, Marilyn D.
• Primary Examiner(s): Smith, Duane
• Assistant Examiner(s): CLEMENTE, ROBERT ARTHUR
• Application Number:
  US10/965,684
• Publication Number:
  US 20050144916A1
• Time in Patent Office: 1,167 Days
• Field of Search: 554/84, 554/86, 554/88, 554/89, 554/92, 554/98, 555/00, 555/10, 555/21, 555/24, 555/29
• US Class Current: 55/498
• CPC Class Codes: B01D 2201/127 with means for keeping the spacing between the pleats
• CPC Class Codes: B01D 2265/06 Details of supporting structures for filtering material, e.g. cores
• CPC Class Codes: B01D 29/21 with corrugated, folded or wound sheets
• CPC Class Codes: B01D 29/213 having a concertina shape
• CPC Class Codes: B01D 46/121 V-type arrangements
• CPC Class Codes: B01D 46/522 with specific folds, e.g. having different lengths

Abstract

A generally cylindrical filter element incorporating nonsymmetrical or asymmetrical V-pleated media. The V-pleated media provides increased filter media per given filter volume, extended filter life, and a smaller filter for equivalent filter life. A smaller filter is generally beneficial for some applications such as aircraft, due to its lower weight. Various features of the filter include asymmetric variable pleat heights applied to a cylindrical or obround filter; defined pleat spacing applied to a variable pleat height element; optimal pleat density; and optimal shape of inlet and outlet.

Claims

1. A cylindrical air filter element comprising:

(a) an extension of filter media configured and arranged in a plurality of media V-packs, each media V-pack having;

(i) a first portion and a second portion, each of the first portion and the second portion having an external edge, an outermost edge, an internal edge and an innermost edge;

(ii) the external edges of the first and second portions joined at an angle of about 4 to 26 degrees;

(iii) the internal edges of the first and second portions joined at an angle of at least 4 degrees less than the external edge angle;

(iv) the outermost edge of each portion being longer than the innermost edge of the respective s portion;

(v) each of the first and second portions having a plurality of media pleats at a density extending generally parallel to the outermost edge of its respective portion; and

(vi) a pleat spacing mechanism maintaining the pleat density;

(b) the plurality of media V-packs configured to form a cylindrical arrangement.

2. The filter element of claim 1, wherein each of the plurality of media pleats extends generally perpendicular to the external edge of its respective portion.

3. The filter element of claim 1, wherein the plurality of media pleats extend generally at an angle of 2 to 13 degrees from perpendicular in respect to the internal edge of the respective portion.

4. The filter element of claim 1, wherein the pleat density is 8 to 15 pleats per inch.

5. The filter element of claim 1, wherein the pleat spacing mechanism are beads of hot melt adhesive spaced no more than 1.5 inches apart.

6. The filter element of claim 1, further comprising a first end cap and an opposite second end cap, the extension of pleated filter media extended between and potted within each of the end caps.

7. The filter element of claim 1, wherein the filter media comprises HEPA media.

8. A cylindrical air filter element comprising:

(a) an extension of filter media configured and arranged in a plurality of media portions, each media portion having;

(i) an external edge, an outermost edge, an internal edge and an innermost edge;

(ii) the external edges of adjacent portions joined together at an angle;

(iii) the internal edges of adjacent portions joined together at an angle of about 4 to 26 degrees, the angle being at least 4 degrees less than the angle of the external edges;

(iv) the outermost edge being longer than the innermost edge;

(v) the internal edges and innermost edges of the plurality of media portions defining an inner perimeter;

(vi) the external edges and outermost edges of the plurality of media portions defining an outer perimeter;

(vii) a plurality of pleats defined by the filter media extending generally parallel to the outermost edge;

(b) the plurality of media portions configured to form a cylindrical arrangement.

9. The filter element of claim 8, wherein:

(a) each of the plurality of pleats extends generally perpendicular to the external edge.

10. The filter element of claim 8, wherein:

(a) the external edges of adjacent portions join together at an angle of about 6 to 24 degrees; and

(b) the internal edges of adjacent portions join together at an angle of about 6 to 24 degrees;

11. The filter element of claim 8, wherein the plurality of pleats extends generally at an angle of 2 to 13 degrees from perpendicular in respect to the internal edge.

12. The filter element of claim 8, wherein the filter media comprises HEPA media.

13. A method of cleaning air for an aircraft cabin, comprising:

(a) providing a filter element comprising;

(i) an extension of filter media configured and arranged in a plurality of media portions, each media portion having;

(A) an external edge, an outermost edge, an internal edge and an innermost edge;

(B) the external edges of adjacent portions joined together at an inlet angle of about 4 to 26 degrees;

(C) the internal edges of adjacent portions joined together at an outlet angle of about 4 to 26 degrees, the outlet angle being at least 4 degrees less than the inlet angle;

(D) the outermost edge being longer than the innermost edge;

(E) the internal edges and innermost edges of the plurality of media portions defining an inner perimeter;

(F) the external edges and outermost edges of the plurality of media portions defining an outer perimeter;

(G) a plurality of pleats defined by the filter media extending generally parallel to the outermost edge;

(b) passing dirty air through the filter media from an inlet side of the filter media to an outlet side of the filter media; and

(c) obtaining cleaned air.

14. The method of claim 13, wherein the step of providing a filter element comprises:

(a) providing a filter element having the plurality of pleats extending generally perpendicular to the external edge.

15. The method of claim 13, wherein the step of providing a filter element comprises:

(a) providing a filter element having the plurality of media portions configured to form a cylindrical arrangement.

16. The method of claim 13, wherein the step of providing a filter element comprises:

(a) providing a filter element having the inlet side of the filter media defined by the outer perimeter and the outlet side defined by the inner perimeter.

17. The method of claim 15, wherein the step of providing a filter element having the inlet side of the filter media defined by the outer perimeter and the outlet side defined by the inner perimeter comprises:

(a) providing a filter element having the angle formed by the external edges of adjacent portions greater than the angle formed by the internal edges of adjacent portions.

18. The method of claim 13, wherein the step of providing a filter element comprises:

(a) providing a filter element comprising HEPA filter media.