Filter elements and methods of manufacturing filter elements
A filter element, for placement in a housing of a filter system, includes a filter medium pack and a seal arrangement having a seal and a seal carrier. The filter medium pack includes, for example, a pleated filter medium or a fluted filter medium. The seal carrier includes an axial side coupled to at least a portion of an axial face of the filter medium pack by a thermal welding manufacturing process. The coupling of the seal to the seal carrier is obtainable by manufacturing the seal arrangement with a multi-material injection molding manufacturing process. The present disclosure further relates to a method for manufacturing a filter element, the method including steps of thermal welding and multi-material injection molding.
1. A filter element comprising:
a filter medium pack, wherein the filter medium pack comprises an outer circumferential face extending in a longitudinal direction and a first axial face transverse to said longitudinal direction; and
a molded single-structure seal arrangement comprising a seal and a seal carrier, wherein the seal comprises a first material and the seal carrier comprises a second material, wherein a transition temperature of the first material is greater than a transition temperature of the second material, and wherein the second material is different from the first material;
wherein the seal carrier comprises a first axial side, and wherein the first axial side of the seal carrier is thermally welded to at least a circumferential portion of the first axial face of the filter medium pack.
2. The filter element of claim 1 , configured for placing in a housing of a filter system,
wherein the molded single-structure seal arrangement separates filtered from unfiltered fluid when the filter element is operationally placed in the housing;
wherein the seal is coupled to the seal carrier, and wherein the coupling of the seal to the seal carrier is obtained by manufacturing the seal arrangement from the first material and the second material using a multi-component injection molding manufacturing process; and
wherein the first axial side of the seal carrier is thermally welded to at least a circumferential portion of the first axial face of the filter medium pack by a thermal welding manufacturing process.
3. The filter element of claim 2 , wherein the thermal welding manufacturing process comprises steps of
heating the first axial side of the seal carrier until at least a portion of the first axial side becomes deformable;
bringing the filter medium pack and the seal carrier together such that the at least circumferential portion of the first axial face of the filter medium pack is being pressed into the first axial side of the seal carrier; and
allowing the first axial side of the seal carrier to cool down such that the first axial side is securely joined with the at least circumferential portion of the first axial face of the filter medium pack.
4. The filter element of claim 1 , wherein:
the first material comprises a rubber, a thermoplastic elastomer, a thermoset elastomer, a thermoplastic vulcanizate, or a mixture or combination thereof; and/or
the second material comprises a thermoplastic.
5. The filter element of claim 1 ,
wherein the first material comprises a thermoplastic elastomer, and the thermoplastic elastomer comprises a polyamide thermoplastic elastomer, a copolyester thermoplastic elastomer, an olefinic thermoplastic elastomer, a styrenic thermoplastic elastomer, a urethane thermoplastic elastomer, or a dynamically vulcanized thermoplastic elastomer, er a or a mixture or combination thereof.
6. The filter element of claim 1 ,
wherein the seal carrier comprises a radial circumferential side extending in said longitudinal direction and enclosing at least partly the outer circumferential face of the filter medium pack, and
wherein the seal surrounds the radial circumferential side to form an outwardly directed radial seal.
7. The filter element of claim 1 ,
wherein the seal carrier comprises a tubular shaped extension extending in said longitudinal direction for forming a fluid entrance channel or a fluid exit channel for the filter medium pack, and
wherein the seal surrounds an outer circumferential surface of the tubular shaped extension for forming an outwardly directed radial seal, or
wherein the seal is located around an inner circumferential surface of the tubular shaped extension for forming an inwardly directed radial seal.
8. The filter element of claim 1 ,
wherein the seal carrier comprises a central opening configured for exiting filtered fluid or for receiving unfiltered fluid, and
wherein the seal is coupled to an inner circumferential surface of the central opening so as to form an inwardly directed radial seal.
9. The filter element of claim 1 ,
wherein the seal carrier comprises a second axial side opposing the first axial side, and
wherein the seal is coupled to the second axial side for forming an axial seal.
10. The filter element of claim 1 ,
wherein the filter medium pack comprises a second axial face opposite to the first axial face, and
wherein the filter element further comprises a closed end cap coupled to the second axial face of the filter medium pack.
11. The filter element of claim 10 wherein the closed end cap is thermally welded to the second axial face of the filter medium pack by a second thermal welding manufacturing process.
12. The filter element of claim 1 , wherein the filter medium pack comprises fluted filter media comprising coiled layers of fluted filter material, wherein each of the coiled layers of fluted filter material comprises inlet flutes and outlet flutes oriented essentially parallel with said longitudinal direction, and wherein flute entrances of the inlet flutes or flute exits of the outlet flutes of at least an outer layer of the coiled layers are blocked by the first axial side of the seal carrier.
13. The filter element of claim 1 , wherein the molded single-structure seal arrangement is formed by a multi-material injection molding manufacturing process.
14. A method of manufacturing a filter element, the method comprising:
providing a filter medium pack having a circumferential face extending in a longitudinal direction, and a first axial face transverse to said longitudinal direction;
providing a seal carrier, wherein a seal arrangement comprises a molded single-structure seal arrangement comprising a seal and the seal carrier, wherein the seal comprises a first material and the seal carrier comprises a second material, wherein a transition temperature of the first material is greater than a transition temperature of the second material; and
applying a thermal welding manufacturing process to couple a first axial side of the seal carrier to at least a circumferential portion of the first axial face of the filter medium pack.
15. The method of claim 14 wherein the thermal welding manufacturing process comprises
heating the first axial side of the seal carrier until at least a portion of the first axial side becomes deformable;
bringing the filter medium pack and the seal carrier together such that the at least circumferential portion of the first axial face of the filter medium pack is being pressed into the first axial side of the seal carrier; and
allowing the first axial side of the seal carrier to cool down such that the first axial side of the seal carrier is becoming securely joined with the at least circumferential portion of the first axial face of the filter medium pack.
16. The method of claim 14 , wherein the method further comprises coupling the seal to the seal carrier by a multi-component injection molding manufacturing process.
17. The method of claim 14 , wherein a processing temperature of the thermal welding process is greater than a transition temperature of a portion of the first axial side of the seal carrier being heated.
18. The method of claim 14 , wherein the method further comprises heating the first axial face of the filter medium pack prior to bringing the filter medium pack and the seal carrier together such that the at least circumferential portion of the first axial face of the filter medium pack is being pressed into the first axial side of the seal carrier.
19. A filter element obtained by the method of claim 14 .