Cabin air filter and filter element for a cabin air filter

Abstract

A cabin air filter is provided with a filter element receptacle and a filter element having a fold pack. The fold pack has a first fold pack area having a fold height that is greater than the fold height of a second fold pack area. The filter element is inserted in an insertion direction into the filter element receptacle. The second fold pack area may form a sword that extends in the insertion direction away from a face of the filter element. The filter element has lateral strips that close off the fold pack on at least two sides of the fold pack. The sword is preferably inherently stable so that it can transmit compressive forces from the filter element to the receptacle.

Claims

1. A cabin air filter comprising: a filter element comprising a fold pack of a filter medium folded into a plurality of folds, the each fold extending from a first lateral side of the fold pack to an opposing second lateral side of the fold pack, the plurality of folds having a first set of fold end edges at the first lateral side, and a second set of fold end edges as the second lateral side of the fold pack; a first lateral strip arranged on, covering and closing off the first set of end edges of the plurality of folds at the first lateral side, an inner side of the first lateral strip adhesively secured directly onto the first set of end edges of the plurality of folds; a second lateral strip arranged on, covering and closing off the second set of end edges of the plurality of folds at the second lateral side, an inner side of the second lateral strip adhesively secured directly onto the second set of end edges of the plurality of folds; wherein the filter element is configured to be inserted in an insertion direction into a filter element receptacle; wherein the filter element comprises a sword that extends outwardly in the insertion direction away from the fold pack at an insertion side of the filter element, wherein the sword is embodied as a plastic part formed of at least one plastic material, the sword having: a base part arranged on an end fold of the fold pack; and a sword projection arrange on and projecting outwardly away from the base part and the fold pack; wherein the sword has an asymmetric shape that is matched to a contour of the filter element receptacle.

2. The cabin air filter according to claim 1, wherein The fold pack is surrounded by a plastic frame of plastic material injection-molded around the fold pack.

3. The cabin air filter according to claim 1, wherein the filter medium is a continuous sheet of filter medium; wherein the continuous sheet of filter medium is a two-layer filter medium or a multi-layer filter medium.

4. The cabin air filter according to claim 1, wherein the filter medium comprises activated carbon.

5. The cabin air filter according to claim 1, wherein the fold pack has a first fold; and a last fold; wherein the fold pack extends continuously from the first fold to the last fold; wherein folds of the plurality of folds have a fold length from the first set of fold end edges to the second set of fold end edges of each fold; wherein the fold pack has fold lengths what vary along the fold pack from the from the first fold to the last fold.

6. The cabin air filter according to claim 5, wherein wherein the fold pack has fold lengths that shorten consecutively from the first fold to the last fold.

7. The cabin air filter according to claim 1, further comprising a first seal strip of a seal material arranged directly on an outer side of the first lateral strip; a second seal strip of the seal material arranged directly on an outer side of the second lateral strip.

8. The cabin air filter according to claim 1, wherein the sword has a length of more than 2 cm in the insertion direction.

9. A method for installing a filter element into a filter element receptacle of a cabin air filter according to claim 1, the method comprising: providing the filter element according to claim 1; inserting the filter element into the filter element receptacle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, features, and details of the invention result from the following description in which embodiments of the invention will be explained in more detail with the aid of the drawings.

(2) FIG. 1A is a top view of a filter element for a cabin air filter having a sword in longitudinal direction of the filter element, wherein the sword is attached as a plastic part onto the filter element;

(3) FIG. 1B is a partial left side sectional view of the filter element of FIG. 1A;

(4) FIG. 1C is a perspective view of the sword of FIGS. 1A and 1B;

(5) FIG. 1D is a rear end view of FIG. 1A showing the insertion end of the filter element;

(6) FIG. 2A is a top view of a filter element for a cabin air filter having a sword in longitudinal direction of the filter element, wherein the sword is manufactured of the filter medium of the fold pack of the filter element;

(7) FIG. 2B is a partial left side section view of the filter element of FIG. 2A;

(8) FIG. 2C is a rear end view of FIG. 2A showing the insertion end of the filter element;

(9) FIG. 3A is a top view of a filter element for a cabin air filter having a sword in the longitudinal direction of the filter element, wherein the sword is made of foam material;

(10) FIG. 3B is a left side view of the filter element of FIG. 3A;

(11) FIG. 3C is a rear end view of FIG. 3A showing the insertion end of the filter element;

(12) FIG. 3D is a perspective view of the filter element of FIG. 3A including an additional plastic part for sealing;

(13) FIG. 3E is a perspective view of the additional plastic part for sealing of FIG. 3D;

(14) FIG. 4A1 is a top view of an alternative configuration of a filter element for a cabin air filter that enables a simple adaptation to geometries of a filter element receptacle;

(15) FIG. 4A2 is a partial left side section view of the filter element of FIG. 4A1;

(16) FIG. 4A3 is a perspective view of the PU foam block of the filter element of FIGS. 4A1 and 4A2;

(17) FIG. 4B1 is a top view of a second alternative configuration of a filter element for a cabin air filter that enables a simple adaptation to geometries of a filter element receptacle;

(18) FIG. 4B2 is a partial left side sectional view of the filter element of FIG. 4B1;

(19) FIG. 4B3 is a rear end view of FIG. 4B1 showing the insertion end of the filter element;

(20) FIG. 4B4 is a perspective view of the PU foam block of the filter element of FIGS. 4B1-4B3; and

(21) FIGS. 5A and 5B are schematic side sectional views of alternative configurations of a filter element for a cabin air filter that enable a simple adaptation to geometries of a filter element receptacle.

(22) In the Figures, same components are provided with same reference characters.

DESCRIPTION OF PREFERRED EMBODIMENTS

(23) FIGS. 1A-1D show a filter element 1 for a cabin air filter comprising a sword 7 in longitudinal direction of the filter element 1, wherein the sword 7 is attached as a plastic part 10 to the filter element 1. The filter element 1 comprises a fold pack 2 which tapers in the insertion direction of the filter element. One side of the filter element 1 is provided with a front plate 3 which, in the mounted state, forms the closure in outward direction and closes off a filter element receptacle. The fold pack comprises a plurality of folds 6 of a filter medium. As a filter medium, paper or nonwoven can be provided; the filter medium may comprise adsorbent materials, e.g. active carbon. The fold pack 2 is provided at the end edges with lateral strips 4 which close off the folds, optionally constitute a termination and a sealing element of the filter medium, when the latter is containing e.g. active carbon. The lateral strips 4 can be manufactured e.g. of nonwoven. On the two lateral strips 4 a seal 5 is applied, for example, a foam material strip that realizes the lateral sealing action of the filter element 1 in the filter element receptacle.

(24) The sealing action of the rear side of the filter element 1 in the insertion direction is realized by a sword 7. The sword 7 is part of a plastic part 10 and can be attached with a U-shaped attachment area 8 of the plastic part onto the filter element 1. The last fold 6 of the fold pack 2 can be inserted into the U-shaped area 8 and glued thereto. TPE (see FIG. 10) means thermoplastic elastomer; PP means polypropylene. The plastic part 10 can be connected or glued or fused to the lateral strips 4.

(25) In an alternative configuration, a plastic material can also be injection-molded around the fold pack 2 and preferably secured to the fold pack, replacing the lateral strips. In this way, the lateral strips can be eliminated and the plastic part 10 may be connected also, e.g. even monolithically formed with the injection molded plastic material of the frame. The sword 7 in all variants can be made of an elastic plastic material or a combination of elastic and less elastic plastic materials. In particular, the sword can be produced by the 2-component method of two different plastic materials or of one or several thermoplastic elastomers (TPE). With such a sword 7, the filter surface area is reduced; however, in particular in case of a form of the fold pack 2 as shown in FIGS. 1A-1D the reduction is in the area of the fold pack that has a reduced width and has possibly at the rim a reduced flow-through action. For different shapes on the part of the filter element receptacle, a filter element 1 for which only the plastic part 10 must be changed can be used. The disadvantage of reduced filter surface area is thus counterbalanced by an advantage in regard to manufacture.

(26) FIGS. 2A-2C show a filter element 1 for a cabin air filter comprising a sword 7 in the longitudinal direction of the filter element 1, wherein the sword 7 is manufactured of the filter medium of the fold pack 6 of the filter element. Accordingly, in contrast to the variant of FIGS. 1A-1D, the sword 7 can be realized from the filter medium itself and an additional component is not required.

(27) FIGS. 3A-3E show a filter element 1 for a cabin air filter comprising a sword 7 in the longitudinal direction of the filter element, wherein the sword is manufactured of foam material. Independent of the material of the sword 7, herein the sword 7 not only can be formed in the plane of the fold pack 2 but can also extend at a slant thereto. In this way, a sealing configuration can be realized, for example, in which the lateral sealing action with the seals 5 extends at different height of the fold pack 2 on the two sides of the filter element. This is particularly advantageous when the material of the seals 5 can be used for the sword 7, e.g. foam material, such as PU (polyurethane). The filter element 1 in FIGS. 3A-3E may comprise an additional plastic part 9 secured thereto that can contribute to a lateral sealing action and may be secured to the sword or serve as a carrier or support for the sword.

(28) FIGS. 4A1-4A3 and 4B1-4B4 as well as FIGS. 5A and 5B show alternative configurations of a filter element 14 for a cabin air filter that enables a simple adaptation to geometries of a filter element receptacle.

(29) In FIGS. 4A1-4A3, a variant is illustrated in which a foam material block with weakened zones enables receiving of non-planar areas of the filter element receptacle. The foam material block can comprise e.g. a plurality of foam material prisms positioned in the filter element plane or a plurality of recesses or cuts.

(30) FIG. 4B4 shows a plastic end member that by means of two swords or lips, possibly also of different geometry, enables adaptation to a filter element receptacle. The plastic end member is visible also in FIGS. 4B1-4B3.

(31) FIGS. 5A and 5B show variants for a filter element 1 in which the filter medium 2 in the insertion or displacement direction is formed such that an adaptation to a filter element receptacle is enabled. For example, the filter medium 2 can be provided with a fold height H1 that is reduced relative to a greater area of the filter element H2 so that in this way an adaptation to a filter element receptacle is provided. The area of reduced fold height H1 not only can terminate, as shown in FIG. 5A, with a fold tip plane of the filter element but can also be staggered, e.g. centrally arranged. The filter medium 2 or the filter bellows can be framed in the area of reduced fold height on both sides by lateral strips 4. The area of reduced fold height H1 can terminate with an L-shaped nonwoven angle piece (lateral strip) 14 of nonwoven material having a first leg of the L-shaped nonwoven angle piece arranged on and adhesively connected to the outermost filter medium end, and a second leg of the L-shaped nonwoven angle member extending between and arranged on a bottom edge of the first and second lateral strips, as shown in FIG. 5A, or a nonwoven U-shaped nonwoven profile 12, as shown in FIG. 5B, arranged on and secured onto an outermost filter medium end of the sword. The outermost filter medium end inserted into the U-shaped nonwoven profile and glued thereto. The lateral strips can be manufactured e.g. of nonwoven. On the two lateral strips 4 a seal 5 (see FIG. 1B) may applied, for example, a foam material strip that realizes the lateral sealing action of the filter element 1 in the filter element receptacle.

(32) 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.