The invention relates to a filter element that is provided with a seal extending about its circumference as well as a method for producing such a filter element.
A filter element serves in general for filtration of, for example, fluid flows or gaseous media such as air flows that, for example, are supplied to the passenger compartment (interior) of a motor vehicle. Aside from their use in motor vehicles, such filters can also be used in other fields, for example, in air-conditioning devices and venting systems of buildings or for filtering liquid media.
The efficiency of a filter depends in particular on the size of the surface area of the filter through which the air passes. In the case of interior air filters of motor vehicles, zigzag-folded (or accordion-folded) filters are therefore primarily used. By means of such a fold arrangement, as a function of the fold height and the fold spacing of the various fold sections of the filter, an effective enlargement of the filter surface area through which the air flow passes can be achieved.
A filter element that is used e.g. as an interior air filter of a motor vehicle, serves for filtering by means of a suitable filter the ambient air that is supplied to the interior of the motor vehicle after having been conditioned. For this purpose, for example, particle filters or odor-removing filters or combinations of such filters are employed that remove by filtration the contained particles and inherent odors from the ambient air. In interior air filters of motor vehicles there is the problem that the filter element must be installed in a corresponding receiving space in such a way that it rests seal-tightly therein and that no gap between filter element and receiving space is formed that would cause leakage.
Filter elements, for example, interior filters, are known in the prior art wherein the filter element is sealed off by a hard or flexible textile lateral strip. Such a lateral strip serves at the same time as a seal relative to the receiving space.
Such filter elements however have the disadvantage that the lateral strips are only insufficiently effective as a seal and frequently hit their limitations. Moreover, the sealing contour of such a textile lateral strip cannot be varied easily.
DE 101 63 026 discloses a filter element comprising a seal that projects past a face of a flat filter. The seal is configured as an unshaped sealing bead made form a thixotropic reaction mixture.
There is therefore a need to provide a filter element with a seal that rests with satisfactory seal tightness against a receptacle in such a way that no leaks can occur.
In addition there is a need that such a filter element with a seal can be produced in a simple and inexpensive way.
Advantageously, the seal should be attachable to a side of the filter element.
The seal should be advantageously configured such that it can be shaped, i.e., non-round shapes should be possible, e.g. one or several projecting sealing strips or lateral beads.
In view of these demands, the present invention has the object to provide a filter element with an improved seal which filter element moreover should be predicable inexpensively.