Retaining plate with improved sealing

Abstract

The invention relates to a retaining plate (2) for a vacuum cleaner filter bag, comprising a base plate in which a passage opening (3) is formed, and a sealing flap (5) for sealing the passage opening (3), wherein the sealing flap (5) is sealed via an elastic element (7; 10) in the sealed position, and wherein a cover element (9) is provided which is connected to the base plate, the sealing flap (5) and/or the elastic element (7) and partially or completely covers the elastic element (7).

Claims

1. A retaining plate for a vacuum cleaner filter bag, comprising a base plate in which a passage opening is formed, and a sealing flap for sealing the passage opening, wherein the sealing flap is biased in a closed position by an elastic element, and a cover element which is connected to one or more of the base plate, the sealing flap or the elastic element and which partially or completely covers the elastic element, wherein the cover element rests against the sealing flap in a surface area of the sealing flap, which encloses the elastic element at least on two sides.

2. The retaining plate according to claim 1, wherein the elastic element is arranged in front of the sealing flap as seen in a sealing direction.

3. The retaining plate according to claim 1, wherein the cover element comprises one or more of a film, a nonwoven or a paper.

4. The retaining plate according to claim 1, wherein the cover element is glued or welded to a part of the retaining plate or is molded onto a part of the retaining plate.

5. The retaining plate according to claim 1, wherein the cover element has an embossing, which is adapted to a shape of the elastic element.

6. The retaining plate according to claim 1, wherein the cover element is pleated or creped.

7. The retaining plate according to claim 1, wherein the cover element is of multi-piece construction.

8. The retaining plate according to claim 7, wherein parts of the multi-piece cover element are positively or materially connected to each other.

9. The retaining plate according to claim 1, wherein the cover element comprises a pivot axis about which a portion of the cover element is pivotable.

10. The retaining plate according to claim 1, wherein the elastic element comprises an elastomer or consists of an elastomer.

11. The retaining plate according to claim 10, wherein the elastic element is molded onto a part of the retaining plate.

12. The retaining plate according to claim 10, wherein the elastic element is molded onto the base plate.

13. The retaining plate according to claim 1, wherein the elastic element is a coil spring, and wherein the coil spring is at least partially enclosed by a sheath.

14. The retaining plate according to claim 1, wherein the elastic element rests loosely on the base plate and is limited in position to a predetermined area by the cover element.

15. A vacuum cleaner filter bag comprising a bag wall and a retaining plate connected thereto in accordance with claim 1.

16. The retaining plate according to claim 1, wherein the cover element is glued or welded to the base plate, or is molded onto the base plate.

17. The retaining plate according to claim 1, wherein the cover element comprises a pivot axis formed by a film hinge about which a portion of the cover element is pivotable.

18. A method of manufacturing a retaining plate for a vacuum cleaner filter bag, the method comprising: providing a base plate with a passage opening and a sealing flap for sealing the passage opening; disposing an elastic element on one or more of the base plate or the sealing flap; and connecting a cover element to one or more the base plate, the sealing flap or the elastic element so that the elastic element is partially or completely covered by the cover element, wherein the cover element is arranged such that it rests against the sealing flap in a surface area of the sealing flap, which encloses the elastic element at least on two sides.

Description

(1) Further features and advantages are described below using the exemplary figures. Thereby showing:

(2) FIG. 1 schematically the construction of an exemplary vacuum cleaner filter bag;

(3) FIG. 2 the schematic structure of an exemplary retaining plate in a top view;

(4) FIG. 3 a cross-section through an exemplary retaining plate;

(5) FIGS. 4A and 4B a top view of further exemplary retaining plates; and

(6) FIG. 5 a perspective view of an exemplary cover element.

(7) FIG. 1 shows the schematic structure of an exemplary vacuum cleaner filter bag. The filter bag comprises a bag wall 1, a retaining plate 2 and an inlet opening, through which the air to be filtered flows into the filter bag. The inlet opening is formed here by a passage opening 3 in the base plate of retaining plate 2 and a passage opening in the bag wall 1 arranged in alignment therewith. The retaining plate 2 is used to fix the vacuum cleaner filter bag in a corresponding retaining mechanism in a vacuum cleaner housing.

(8) The bag wall 1 comprises at least one nonwoven layer, for example, made of a melt-spun fine fiber nonwoven (meltblown nonwoven) or a filament-spun nonwoven (spun bond).

(9) The retaining plate 2 comprises a base plate made of a plastic material, for example polypropylene.

(10) FIG. 2 shows a top view of an exemplary retaining plate, which can be used in conjunction with a filter bag as shown in FIG. 1. This shows the retaining plate 2 with the passage opening 3. The base plate of retaining plate 2 is shown here schematically rectangular, but it can have any shape, which can correspond in particular with the corresponding holding device in the vacuum cleaner housing.

(11) FIG. 2 also shows a sealing lip 4 enclosing the passage opening 3. The sealing lip 4 can comprise a thermoplastic elastomer, for example, based on polypropylene, or consist of it. The sealing lip 4 is designed to prevent or limit the escape of dust from the vacuum cleaner filter bag by sealing the area between the inner edge of the passage opening 3 and the outside of a connection nozzle of the vacuum cleaner. However, the sealing lip shown here is merely optional. It is also conceivable that the bag material of the vacuum cleaner filter bag itself could be used as a sealing ring, as shown, for example, in DE 102 03 460. It is also possible to use a sealing membrane between retaining plate 2 and bag wall 1, as shown in EP 2 044 874. It can also be provided without any sealing.

(12) FIG. 2 also shows a sealing flap 5, which can be pivoted around a joint 6. The hinge 6, in particular can be a film hinge. The sealing flap 5 seals the passage opening 3 when the vacuum cleaner is not in use, in particular when the filter bag is removed from the vacuum cleaner.

(13) The sealing flap 5 is biased by an elastic element 7 in the sealing position. The elastic element 7 is connected to the base plate of the support plate 2 in the area of a bearing 8. In this example, the elastic element 7 is arranged in the sealing direction in front of the sealing flap 5. The top view of FIG. 2 is therefore on the side of the retaining plate 2, which is to be connected to the bag wall 1. After connecting the retaining plate 2 with the vacuum cleaner filter bag, the elastic element 7 is therefore located in the dust chamber, i.e. inside the filter bag.

(14) The elastic element 7 can be a leaf spring, in particular a curved leaf spring, a coil spring or an elastomeric element. When the sealing flap 5 is pivoted around the joint 6 into an open position, the elastic element 7 is compressed and/or deflected in such a way that a resetting spring force is produced which is applied to the sealing flap 5. If the vacuum cleaner filter bag is removed from the vacuum cleaner housing, for example, the force opening the sealing flap 5 is omitted and the sealing flap 5 is returned to the closed position via the elastic element 7.

(15) However, it has been found that the sealing function is not always ensured with known retaining plates, since dirt particles, in particular suction material, are disposed in the area of the elastic element 7 and hinder its function.

(16) The retaining plate of FIG. 2 therefore also comprises a cover element 9, which is connected to the base plate of the retaining plate 2 and the sealing flap 5 and covers the elastic element 7 towards the dust chamber, i.e. away from the base plate of the retaining plate 2. This cover element 9 separates or shields the elastic element 7 from the dust chamber. As a result, no suction material or less thereof enters the area of the elastic element, in particular the area immediately adjacent to the bearing 8, so that its function is not impaired or less impaired.

(17) It is also conceivable that the cover element 9 is only connected to the base plate and rests loosely on the sealing flap 5. A connection with the elastic element 7 is also alternatively or additionally possible.

(18) The cover element may comprise a film, in particular an elastic film, for example made of a thermoplastic elastomer. The film may be less than 1 mm thick, in particular less than 0.5 mm, in particular less than 0.1 mm. It is also possible that the cover element 9 comprises or consists of a non-woven fabric, a paper or a woven tape. A laminate of different materials, such as nonwoven and film or paper and film, is also conceivable.

(19) The cover element 9 can be detachably or non-destructively connected to the base plate and/or the sealing flap. For example, the cover element 9 can be glued or welded to the desired area of the base plate and/or the sealing flap. The cover element 9 can also have a self-adhesive area for the connection. A positive or non-positive connection is also possible, for example a snap-fit connection (click connection).

(20) Finally, the cover element 9 can also be connected to the base plate and/or the cover flap 5 by means of an injection molding process. In this case, the cover element 9 can be injected simultaneously onto the retaining plate 2 with a sealing lip 4, if present In this case, the cover element 9 may be made of the same material as the sealing lip 4, in particular a thermoplastic elastomer. Such a two-component injection molding process eliminates the additional work involved in gluing or welding on the cover element 9.

(21) In particular, if the cover element 9 comprises a film or a nonwoven, the film or the nonwoven can be embossed. This can give the cover element 9 a form that is adapted to the form of the elastic element 7, so that the movement of the elastic element 7 is not restricted or to a lesser extent during the opening of the sealing flap 5. Alternatively or additionally, cover element 9 can also be pleated or creped. For example, the cover element 9 can be in the form of a bellows. The folds of the pleated or creped cover element 9 can be in particular perpendicular to the direction of movement of the sealing flap and/or the elastic element.

(22) Cover element 9 can be embossed by hot or cold stamping or by deep-drawing or vacuum deep-drawing.

(23) Alternatively, the cover element 9 can also consist of an injection-molded part or a deep-drawn part, which is connected to the base plate, the sealing flap and/or the elastic element 7 in a material-locking, form-fitting or force-fitting manner, in particular by gluing or welding.

(24) If the cover element 9 has a stiffness, which would oppose the mobility of the elastic element 7, the cover element 9 can also have a film hinge, around which part of the cover element 9 can be pivoted. Alternatively or additionally, the cover element 9 can be made in two or more pieces, whereby the parts of the multi-piece cover element are form-fitted or firmly bonded, especially by welding, gluing or clicking (snap-fit).

(25) FIG. 3 shows a cross-section through the exemplary retaining plate 2 of FIG. 2, showing that the elastic element 7 is completely shielded from the dust chamber by the cover element 9, i.e. the environment, which lies inside the filter bag after connecting the retaining plate 2 with a filter bag.

(26) The elastic element 7 can be a coil spring. In this case, a cover element in the form of a sheath may be provided as an alternative or in addition to cover element 9 of FIGS. 2 and 3. For example, the coil spring can be arranged at least partially in a plastic film tube. The sheathing can be easily formed by two plastic films which are welded together all around, with the coil spring located between the two films. Also a one-piece plastic hose can be pulled over the coil spring.

(27) This plastic coating makes it possible to prevent dust from getting between the coils of the coil spring, which could lead to a reduction in the function of the coil spring.

(28) As an alternative to the coil spring, the elastic element 7 can also be formed by an elastomeric cord or an elastomeric band. A vulcanized silicone elastomer in particular can be used for the elastic element. This has the advantage that it can be injected onto the retaining plate. Crosslinked liquid silicone rubber (LSR) or crosslinked solid silicone (High-Consistency Rubber, HCR) are particularly suitable. The elastic element made of an elastomer has its own elasticity. In addition, the elastic element can also have a form that lends further elasticity due to its structure.

(29) FIG. 4A shows another example of a retaining plate 2 with sealing flap 5. In this case the elastic element 10 runs transversely to the opening movement of the sealing flap 5. The elastic element 10 can in turn take the form of a coil spring or an elastomeric strap. In this example, again a cover element 9 is provided, which in this case is connected to the cover flap 5, but only partially covers the elastic element 10. In particular, the cover element 9 in this example covers the area of the elastic element 10, which interacts with the sealing flap 5 via a projection 11. This area is the functional area for applying force to the sealing flap 5 via the elastic element 10. The projection 11 serves to hold the elastic element 10 in a holding position. If suction material were disposed in this area, the function of the projection 11 would be disrupted, and thus the function of the elastic element 10 as well.

(30) FIG. 4B shows another example of an arrangement of a cover element 9, in which case, the cover element 9 must be absolutely elastic. In the open position of the sealing flap 5, the spring element should be covered as far as possible.

(31) FIG. 5 shows an example of a possible cover element 9, which is in particular pleated, i.e. has several pleats in the sense of a bellows. While a bellows is usually tubular, the cover element 9 is rather dome-shaped. By folding, it is possible to provide a relatively firm cover element without significantly disrupting the mobility of the underlying elastic element.

(32) It goes without saying that the features mentioned in the exemplary embodiments described above are not limited to these special combinations and are also possible in any other combinations. Furthermore, it goes without saying that neither the vacuum cleaner filter bag shown nor the elements of the retaining plate are realistically dimensioned in the figures. In addition, the geometries or the elements shown are not limited to the examples shown.