Z-filter media pack arrangement; and, methods
Z-filter media pack arrangements and methods for providing them are described. Certain aspects concern a cured-in-place seal on an outside of a coiled z-filter media combination. Other aspects concern a cured-in-place center core, most preferably one that has opposite concave ends with seal arrangements configured to seal a lead end portion of the coiled z-filter media combination.
1. An air filter cartridge comprising:
(a) a coiled media combination comprising a fluted sheet secured to a facing sheet and defining a set of inlet flutes and a set of outlet flutes; the coiled media combination defining:
(i) an outer side wall extending between first and second opposite flow ends;
(ii) a coil center; and,
(iii) a media combination lead end positioned inside of the coil within the coil center; and,
(b) a mold-in-place center core positioned within the coil center and comprising foamed polyurethane in a center of the coiled media providing at least a portion of a lead end seal.
2. An air filter cartridge according to claim 1 wherein:
(a) the mold-in-place center core has opposite ends at least one of which has an axially, outwardly, projecting end skirt to seal a portion of the lead end.
3. An air filter cartridge according to claim 1 wherein:
(a) the core has a density of no greater than 0.24 g/cc.
4. An air filter cartridge according to claim 1 wherein:
(a) the coiled media combination has a circular perimeter shape.
5. An air filter cartridge according to claim 1 wherein:
(a) the coiled media combination has an oval perimeter shape with opposite curved ends.
6. An air filter cartridge according to claim 1 wherein:
(a) the media pack has first and second, opposite, flow ends;
(b) a mold-in-place seal is positioned on the outside wall of media pack in extension between the first and second, opposite, flow ends, the molded-in-place seal being formed by positioning a portion of the media pack appropriately in a mold and molding the seal in place on the media pack; and,
(c) a mold-in-place housing seal arrangement is secured to the media pack and extending around the media pack.
7. An air filter cartridge according to claim 6 wherein:
(a) the mold-in-place seal positioned on the media pack in extension between the first and second, opposite, flow ends is molded integral with the mold-in-place housing seal arrangement.
8. An air filter cartridge according to claim 6 wherein:
(a) the mold-in-place seal positioned on the media pack in extension between the first and second, opposite, flow ends is a foamed polyurethane mold-in-place seal.
9. An air filter cartridge according to claim 6 wherein:
(a) each one of the mold-in-place housing seal arrangement and mold-in-place seal on the media pack in extension between the first and second flow ends has an as-molded density of no greater than 0.35 g/cc.
10. An air filter cartridge according to claim 6 wherein:
(a) the mold-in-place seal positioned on the media pack in extension between the first and second, opposite, flow ends is a complete overmold around the media pack.
11. An air filter cartridge according to claim 6 wherein:
(a) the mold-in-place seal positioned on the media pack in extension between the first and second, opposite, flow ends is a partial overmold.
12. An air filter cartridge according to claim 6 wherein:
(a) the housing seal arrangement comprises an axial pinch seal.
13. An air filter cartridge according to claim 12 wherein:
(a) the axial pinch seal has opposite housing engagement surfaces spaced at least 4 mm apart.
14. An air filter cartridge according to claim 6 wherein:
(a) the coiled media combination comprises:
(i) an outward, axial, projection at the first flow end defining a coiled, stepped, side edge and projecting in axial extension outwardly; and,
(ii) an inward, axial, projection at the second flow end defining a coiled, stepped, side edge in axial extension inwardly.
15. An air filter cartridge according to claim 14 wherein:
(a) the first flow end has a central, non-tapered, portion extending across a distance of at least 20% of a largest axial cross-section of the coiled media combination; and,
(b) the second flow end has a central, non-tapered, portion extending across a distance of at least 20% of a largest axial cross-section of the coiled media combination.
16. An air filter cartridge according to claim 6 wherein:
(a) the coiled media combination has a circular perimeter shape.
17. An air filter cartridge according to claim 6 wherein:
(a) the coiled media combination has an oval perimeter shape with opposite curved ends.
18. An air filter cartridge according to claim 17 wherein:
(a) the coiled media combination has a racetrack perimeter shape with two, opposite, curved ends and two, opposite, straight sides.