RETAINER PLATE WITH A SEAL ELEMENT

Abstract

The invention relates to a retainer plate for a vacuum cleaner filter bag, comprising a base plate in which a passage opening is formed, and a sealing element which is arranged at the edge of the passage opening, wherein the sealing element comprises at least one extruded film made of a thermoplastic elastomer, TPE.

Claims

1. A retainer plate for a vacuum cleaner filter bag, comprising: a base plate with a passage opening arranged therein, and a seal element arranged at the edge of the passage opening, wherein the seal element comprises at least one extruded film made of a thermoplastic elastomer (TPE).

2. The retainer plate according to claim 1, wherein the at least one extruded film is a blown film or a cast film.

3. The retainer plate according to claim 1, wherein the at least one extruded film has a first side and an opposite second side, wherein the first side has a greater roughness than the second side.

4. The retainer plate according to claim 1, wherein the melt flow index of the thermoplastic elastomer of the at least one extruded film is less than 10 g/10 min.

5. The retainer plate according to claim 1, wherein the thickness of the at least one extruded film is less than 0.35 mm.

6. The retainer plate according to claim 1, wherein the at least one extruded film is welded to the base plate.

7. The retainer plate according to claim 1, wherein the seal element comprises several layers of extruded films made of the TPE.

8. The retainer plate according to claim 7, wherein at least two of the layers of extruded films consist of different plastics.

9. The retainer plate according to claim 1, wherein the base plate comprises or consists of a thermoplastic material.

10. The retainer plate according to claim 9, wherein the thermoplastic material is a recycled plastic.

11. The retainer plate according to claim 1, wherein the base plate is a punched part, a deep-drawn part or an injection-molded part.

12. A vacuum cleaner filter bag comprising a retainer plate according to claim 1.

13. The retainer plate according to claim 10, wherein the recycled plastic comprises recycled polyethylene terephthalate (rPET).

14. The retainer plate according to claim 5, wherein the thickness of the at least one extruded film is less than 0.25 mm.

15. The retainer plate of according to claim 14, wherein the thickness of the at least one extruded film is less than 0.15 mm.

16. The retainer plate according to claim 4, wherein the melt flow index of the thermoplastic elastomer of the at least one extruded film is less than 5 g/10 min.

17. The retainer plate according to claim 16, wherein the melt flow index of the thermoplastic elastomer of the at least one extruded film is less than 3 g/10 min.

Description

[0037] Further features and advantages of the invention are described below using the exemplary figures, of which:

[0038] FIG. 1 schematically shows the structure of an exemplary vacuum cleaner filter bag; and

[0039] FIG. 2 shows the schematic structure of an exemplary retainer plate in a top view.

[0040] FIG. 1 shows the schematic structure of an exemplary vacuum cleaner filter bag. The filter bag comprises a bag wall 1, a retainer plate 2, and an inflow opening through which the air to be filtered flows into the filter bag. The inflow opening is here formed by a passage opening 3 in the base plate of the retainer plate 2 and a passage opening in the bag wall 1, which is aligned with it. The retainer plate 2 serves to fix the vacuum cleaner filter bag in a corresponding holder in a vacuum cleaner housing.

[0041] The bag wall 1 comprises at least one nonwoven layer, for example of a melt-spun fine fiber spunbonded nonwoven (melt-blown nonwoven) or a filament spunbonded nonwoven (spunbond).

[0042] The retainer plate 2 comprises a base plate made of a thermoplastic material. For example, recycled plastic material such as recycled polypropylene (rPP) or recycled polyethylene terephthalate (rPET) can be used for the base plate.

[0043] There are relevant international standards for many plastic recyclates. As for PET plastic recyclates, for example, DIN EN 15353:2007 is relevant.

[0044] The term recycled plastics used for the purposes of this invention is to be understood as synonymous with plastic recyclates. For the definition of the term, reference is made to the standard DIN EN 15347:2007.

[0045] A top view of an exemplary retainer plate, which can be used in combination with a filter bag as shown in FIG. 1, is shown in FIG. 2. It shows the retainer plate 2 with passage opening 3. The base plate of the retainer plate 2 is here schematically shown to be rectangular, but may have any shape, which may correspond in particular to the corresponding retaining device in the vacuum cleaner housing.

[0046] Moreover, FIG. 2 shows a seal element 4 arranged at the edge of the passage opening 3. The seal element 4 is intended to prevent or limit the escape of dust from the vacuum cleaner filter bag by sealing the area between the edge of the passage opening 3 and the outside of a connection nozzle of the vacuum cleaner. For this purpose, the seal element 4 comprises a passage opening which overlaps the passage opening 3 of the base plate. Since the area of the passage opening in the seal element 4 is smaller than the area of the passage opening 3 of the base plate, an annular sealing lip is formed which protrudes inwards over the edge of the passage opening 3 of the base plate, i.e. towards the center of the passage opening 3.

[0047] The seal element 4 is welded to the base plate and comprises at least one extruded film of a thermoplastic elastomer, TPE, connected to the base plate.

[0048] An element whose thickness is considerably less than its extension perpendicular to it (length and width) is designated as a film. For example, the film may have a thickness, particularly a constant thickness, of less than 0.35 mm, for example 0.13 mm.

[0049] Unlike injection-molded seal elements, the seal element 4 can be made of a thermoplastic elastomer with a low melt flow index, in particular a melt flow index of less than 10 g/10 min. The melt flow index is defined according to ISO 1133 and is measured by means of a capillary rheometer. The melt flow index indicates the mass of the thermoplastic melt which is forced through a predetermined nozzle under a predetermined pressure in 10 minutes.

[0050] The at least one extruded film can be a blown film or a cast film.

[0051] It has been found that such extruded films have a higher elasticity than injection-molded structures. Therefore, the sealing effect of the seal element 4 is improved compared to injection-molded sealing lips.

[0052] The seal element 4 may have a greater roughness on the side with which it comes into contact with the nozzle of the vacuum cleaner during operation than on the opposite side. This can be achieved by calendering a surface structure onto the film.

[0053] The seal element 4 can also comprise several layers of extruded films, wherein the layers can consist of a uniform plastic or of different plastics. In particular, the layer to be connected to the base plate may comprise a plastic which is compatible with the plastic material of the base plate so that a secure welded joint can be produced.

[0054] FIG. 2 also shows an optional closure flap 5 which can be pivoted around a hinge 6. The hinge 6 is specifically a film hinge. The closure flap 5 serves to close the passage opening 3 when the vacuum cleaner is not in use, especially when the filter bag is removed from the vacuum cleaner.

[0055] The closure flap 3 may also be made of a recycled plastic material, for example the same material as the base plate.

[0056] The closure flap 5 is pretensioned in the closing position by a spring element 7. The spring element 7 may be made of a new plastic material molded onto the closure flap 5. Alternatively, other known spring elements, for example a metallic leaf spring, can be used. To influence the spring characteristic curve, a spring pocket 8 is provided which can be designed according to EP 1 849 392 A1.

[0057] In this example, the spring element 7 is arranged in front of the closure flap 5, seen in the closing direction. The top view of FIG. 2 is thus on the side of the retainer plate 2 which is to be connected to the bag wall 1. The spring element 7 is therefore located in the dust compartment, i.e. inside the filter bag, after connecting the retainer plate 2 to the vacuum cleaner filter bag.

[0058] It goes without saying that features mentioned in the embodiments described above are not limited to these special combinations and are also possible in any other combination. It is also understood that geometries shown in the figures are only exemplary and are also possible in any other design.