DE102005012492A1 - Filter insert has box frame with elastic outer lip and inner fan-fold polyurethane filter panel - Google Patents

Abstract

A filter insert has a box frame (1) around a filter medium (2). The frame outer face bears an elastic lip over an angled seal flange. The filter insert is a fan-fold filter panel of polyethylene foam. An independent claim is included for the production of the above filter insert.

Description

technical area

The The present invention relates to new filter cartridges and an improved one Process for their preparation.

State of technology

Filter cartridges are usually equipped with seals to the medium to be cleaned as possible Completely through the filter medium.

Out The state of the art is a wide variety of sealing concepts known.

So DE-A-196 34 720 describes a filter cartridge with one of a Filter medium existing hollow cylindrical filter body, the is provided on at least one end face with an end plate, which has a sealing element. This consists of a carrier medium and a sealing medium. In one embodiment, the sealing medium in one in the carrier medium provided groove inserted.

Out DE-A-198 13 320 describes an end disk for an annular, radially flow-through filter, the radially inside and / or outside with a radially acting sealing ring made of an elastic material is provided.

Of the Sealing ring is over its entire circumference on the one hand directly with an axial end face area of the filter material and on the other hand with the area released this area End disk tightly connected.

Out DE-A-195 48 197 is a method for producing a pleated filter insert known in which a pleated filter pack inserted into a tool and a cavity thereafter remaining in the tool for formation a frame enclosing the pleated filter pack with a liquefied, filled polymeric material and the material is subsequently solidified. This document will proposed with the production of the frame at least one circumferential, consisting of the material of the frame elastically deformable sealing lip to generate and consolidate these in parallel to the solidification of the frame. From this document, therefore, frames and seals are made of the same Material revealed.

presentation the invention

outgoing of this prior art, the present invention was the The object of the invention is to provide a filter insert in which the most diverse Material combinations for Frame and seals can be used.

A Another object of the invention was to provide a Filter insert with improved performance characteristics.

A Another object of the present invention is to provide an improved manufacturing process characterized by high productivity and accordingly by reduced unit costs distinguished.

The present invention relates to a filter cartridge comprising a frame ( 1 ), a filter medium inserted therein ( 2 ), a along the entire outer circumference of the frame circumferential groove ( 3 ) and a circumferential in the joint elastomeric seal ( 4 ) for sealing the frame ( 1 ) from the surroundings ( 5 ).

Of the Frame of the filter insert according to the invention can consist of different materials. Examples are metals or plastics, preferably thermoplastics.

to Generation of the frame can advantageously polypropylene, ABS (acrylonitrile / butadiene / styrene) and / or polyesters are used. When using polypropylene is an advantage that this material is viscoelastic and therefore also while a long service life of the filter cartridge damage the Frame, for example by breakage, safely avoided. Besides that is Polypropylene, especially with regard to economical production the filter insert of advantage. ABS is also available at low cost and extraordinarily warpage. Is for the polyester frame is used, the filter insert is predominant sorted, since filter pack and frame can be made of polyester and therefore, following their use, it is easy to recycle supplied can be.

Of the Frame of the filter insert according to the invention can be varied, adapted to the particular application Have geometries. For example, the frame may be a round or preferably have rectangular cross-section.

As filter media for use in the filter insert according to the invention can also under different materials and geometries are used. Preference is given to pleated filters ( 2a ) used. These are preferably made of nonwoven materials and / or papers. The pleated filters preferably have lateral reinforcing strips, which in turn carry a seal to the space between the inner wall of the frame ( 1 ) and pleated filters ( 2a ) seal.

Along the entire outer circumference of the frame ( 1 ) is a circumferential joint ( 3 ) intended. This can be done by one along the outer circumference in the frame ( 1 ) extending groove or by a running along the outer periphery of the frame and the frame ( 1 ) projecting bridge, which together with the frame ( 1 ) the joint ( 3 ). Gap ( 3 ) can be generated by methods known per se. Examples are mechanical processing methods, such as milling, or the formation of the joint ( 3 ) in the shaping of the frame ( 1 ), for example by spraying or gluing a web or by forming a groove.

Into the fugue ( 3 ) is an encircling elastomeric seal ( 4 ) for sealing the frame ( 1 ) from the surroundings ( 5 ) brought in.

The the elastomeric seal-forming material may be arbitrary. typically, it is a foamed Plastic, preferably a foamed polyurethane.

This can be achieved by inserting a preformed elastomeric seal ( 4 ) into the fugue ( 3 ) respectively.

Preferably, the elastomeric seal ( 4 ) in the fugue ( 3 ) educated. For this purpose, a liquid precursor of an elastomer in the joint ( 3 ) and this is the formation of the circumferential elastomeric seal ( 4 ) implemented. The type of implementation depends on the type of precursor used. For example, the reaction may be initiated by heating or irradiation. In the reaction, the resulting elastomeric material usually expands, filling the joint ( 3 ) completely and partially occurs in their environment. This creates a framework ( 1 ) on the outside circumferential seal of elastomeric material.

The circumferential gap ( 3 ) may have any cross-sections. Preferably, such configured cross-sections that the joint ( 3 ) is able to take up a volume of liquid which is at least half, preferably at least two thirds, of the total volume of the joint (in the frame in the production position for the elastomeric seal). 3 ).

In this embodiment of the invention, it is possible to use the joint ( 3 ) completely circumferentially with liquid precursor for the elastomeric material to fill and in a subsequent step, the reaction to the elastomeric gasket ( 4 ). A section-wise filling and reacting can be omitted in this embodiment.

The elastomer seal ( 4 ) may also have different cross sections. When manufactured within the joint ( 3 ), the resulting elastomer is the entire interior of the joint ( 3 ) and partly over the outer edges of the joint ( 3 ) so that a portion of the elastomeric material passes over the surface of the outer frame ( 1 ) including one the fugue ( 3 ) forming bridge protrudes. This ensures that the seal fits the contours of the adjacent housing surface particularly well and along the entire circumference of the filter insert is a matching contact pressure on the housing. As a result, the filter insert is centered automatically within the housing such that the contact pressure on the surface of the housing in all sections of the same size.

The invention also relates to a method for producing the filter insert described above comprising the measures:
i) generating one along the entire outer circumference of a frame ( 1 ) circumferential joint ( 3 )
ii) inserting a filter medium ( 2 ) in the framework ( 1 )
iii) introducing a liquid precursor of an elastomer into the joint ( 3 ), and
iv) reaction of the precursor of the elastomer to form the circumferential elastomeric seal ( 4 ).

In a particularly preferred embodiment of the process according to the invention, a foamable plastic is introduced into the joint as precursor of an elastomer ( 3 ) and in the reaction of the precursor of the elastomer to the elastomeric seal ( 4 ) a foam is generated.

The invention also relates to the use of one along the entire outer circumference of a frame ( 1 ) of a filter insert extending joint ( 3 ) for making one in the joint ( 3 ) circumferential elastomeric seal ( 4 ).

Summary the drawing

following becomes the filter insert according to the invention closer to the drawings described. Shown are:

1 : A filter insert according to the invention in supervision

2 A filter insert according to the invention in cross section along the in 1 illustrated line

3 : A filter insert according to the invention in a lateral view

Embodiment of the invention

The in 1 illustrated filter element shows frame ( 1 ) and a filter medium ( 2 ).

A cross section of this filter insert is in 2 shown. You can see frames ( 1 ), Filter medium ( 2 ) extending along the entire circumference of the frame ( 1 ) circumferential joint ( 3 ) and those in the fugue ( 3 ) circumferential elastomeric seal ( 4 ). The joint ( 3 ) is removed from the frame ( 1 ) and a web attached thereto.

The in 3 illustrated filter element shows frame ( 1 ), a filter medium inserted therein ( 2 ), the web, which the along the entire outer circumference of the frame circumferential groove ( 3 ) as well as those in the joint ( 3 ) formed elastomeric seal ( 4 ).

Claims (7)

Filter element comprising a frame ( 1 ), a filter medium inserted therein ( 2 ), one along the entire outer circumference of the frame ( 1 ) around-running joint ( 3 ) and one in the fugue ( 3 ) circumferential elastomeric seal ( 4 ) for sealing the frame ( 1 ) from the surroundings ( 5 ). Filter insert according to claim 1, characterized in that the filter medium is a folded filter ( 2a ). Filter insert according to claim 1, characterized in that the elastomeric seal ( 4 ) is a foamed plastic, preferably a foamed polyurethane. Filter insert according to claim 1, characterized in that the circumferential joint ( 3 ) has a cross section designed in such a way that the joint ( 3 ) in the production position for the elastomeric seal ( 4 ) frame ( 1 ) can absorb a volume of liquid which is at least half, preferably at least two-thirds of the total volume of the joint ( 3 ). A method of manufacturing the filter cartridge according to claim 1, comprising the steps of: i) generating one along the entire outer circumference of a frame ( 1 ) circumferential joint ( 3 ), ii) inserting a filter medium ( 2 ) in the framework ( 1 iii) introducing a liquid precursor of an elastomer into the joint ( 3 ), and iv) reaction of the precursor of the elastomer to form the circumferential elastomeric seal ( 4 ). A method according to claim 5, characterized in that as a precursor of an elastomer, a foamable plastic in the joint ( 3 ) and that in the reaction of the precursor of the elastomer to the elastomeric seal ( 4 ) a foam is generated. Using an outside along the entire circumference of a frame ( 1 ) of a filter insert extending joint ( 3 ) for making one in the joint ( 3 ) circumferential elastomeric seal ( 4 ).