Filter Element or Adsorber Element with Enclosed Adsorption Particles and Method for Its Manufacture

Abstract

A filter element has a filter medium that is made of at least two filter web layers and an adsorptive layer of adsorptive particles which adsorptive layer is substantially enclosed by the at least two filter web layers with the exception of lateral open edges. A sealing compound seals the lateral open edges at least during manufacture of the filter element. A frame part is attached by injection molding to the filter medium after sealing the open lateral edges with the sealing compound.

Description

BRIEF DESCRIPTION OF THE DRAWING

One embodiment of the invention will be explained in connection with the drawings in more detail.

FIG. 1 shows a section of the filter medium comprised of two zigzag shaped folded filter webs and enclosed adsorptive particles.

FIG. 2 is a schematic illustration of the filter element with sealed lateral edges of the filter medium.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a section of a filter medium 1 that, for example, can be used as an air filter for the intake of an internal combustion engine or as a filter for the interior of a passenger compartment of a vehicle. Layers of zigzag-shaped folded filter webs 2 and 3 are present between which an adsorptive layer of adsorptive particles 4, in the illustrated embodiment, activated carbon, is enclosed.

FIG. 2 shows a filter element 5 comprising in the lateral edge area a frame part 6 that mechanically secures the filter medium 1 at its lateral edges 7.

On the lateral edges 7 of the filter medium 1, a sealing compound 8 is applied; it is illustrated in dashed lines. For example, the compound 8 can be a wax that is liquefied by heat and that hardens or solidifies when cooled. However, the materials and methods described above in this specification can be used also.

For producing the filter element 5, the zigzag-shaped folded filter medium 1 that has been cut to the desired size is secured in a holding device (illustrated only schematically by the double arrows in FIG. 2); subsequently, the initially soft sealing compound 8 is applied to the open lateral edges by means of an appropriately designed applicator head in the form of a glue nozzle or a ladle and the sealing compound 8 penetrates into the filter medium 1 to a minimal depth so that the open lateral edges are now sealed and sealed lateral edges 7 are produced. After application or introduction (penetration) of the sealing compound 8, the frame part 6 is then laterally molded onto the filter medium 1 by means of an injection molding device for plastic material.

The specification incorporates by reference the entire disclosure of German priority document 10 2006 043 729.2 having a filing date of Sep. 13, 2006.

While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

1. A filter element comprising: a filter medium comprising at least two filter web layers and an adsorptive layer of adsorptive particles which adsorptive layer is substantially enclosed by the at least two filter web layers with the exception of lateral open edges;a sealing compound sealing the lateral open edges at least during manufacture of the filter element.

2. The filter element according to claim 1, wherein the at least two filter web layers are zigzag-shaped folded layers.

3. The filter element according to claim 2, further comprising a fame part connected at least to the lateral edges for mechanically securing the filter medium.

4. The filter element according to claim 3, wherein the frame part is an injection-molded plastic part.

5. The filter element according to claim 1, wherein the adsorptive particles are activated carbon particles.

6. The filter element according to claim 1, wherein the adsorptive particles are ion exchanger particles.

7. The filter element according to claim 1, wherein the adsorptive particles are ion exchanger resin particles.

8. The filter element according to claim 1, wherein the sealing compound is a wax that liquefies when heated and solidifies when cooled.

9. The filter element according to claim 1, wherein the sealing compound is a glue.

10. The filter element according to claim 1, wherein the sealing compound is an edge area of the at least two filter web layers that is softened or melted by a thermal method or a chemical method.

11. A method for producing a filter element according to claim 2, the method comprising the steps of: securing a filter medium, comprising at least two zigzag-shaped folded filter web layers and an adsorptive layer of adsorptive particles enclosed between the at least two zigzag-shaped folded filter web layers, in a holding device;applying a sealing compound to open lateral edges of the filter medium to seal the open lateral edges to produce sealed lateral edges; andinjection molding a frame part laterally onto the filter medium provided with the sealed lateral edges.

12. The method according to claim 11, wherein in the step of applying a metered amount of heated wax is sprayed onto the open lateral edges of the filter medium.

13. The method according to claim 11, wherein in the step of applying the open lateral edges are immersed into heated wax.

14. A method for producing a filter element comprising a filter medium comprising at least two filter web layers and an adsorptive layer of adsorptive particles which adsorptive layer is substantially enclosed by the at least two filter web layers with the exception of lateral open edges; the method comprising the step of: sealing the lateral open edges of the filter medium with a sealing compound before a frame part is applied to the filter medium.