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 biased in the sealed position via an elastic element (7), wherein the elastic element (7) is arranged in front of the sealing flap (5) when viewed in the sealing direction; and wherein the elastic member (7) comprises an elastomer, or the elastic member (7) comprises a coil spring (9), wherein the coil spring (9) is at least partially enclosed by a sheath (10).

Claims

1. A retaining plate for a vacuum cleaner filter bag, comprising a base plate, wherein a passage opening is formed, and a sealing flap for sealing the passage opening, wherein the sealing flap is biased by an elastic element in a closed position, and wherein the elastic element is arranged in front of the sealing flap when viewed in a sealing direction; and wherein the elastic element comprises a coil spring, wherein the coil spring is at least partially enclosed by a sheath.

2. The retaining plate according to claim 1, wherein the sheath comprises a plastic, a nonwoven, a paper or combinations thereof.

3. The retaining plate according to claim 2, wherein the sheath comprises two films joined together on at least two sides to form a pocket, in which the coil spring is arranged.

4. The retaining plate according to claim 2, wherein the sheath comprises a film, of which at least two opposite edges are joined together to form a pocket, in which the coil spring is arranged.

5. The retaining plate according to claim 1, wherein one end of the elastic element is connected to a part of the retaining plate, and a second end rests loosely against a part of the retaining plate.

6. The retaining plate according to claim 1, wherein the elastic element is designed or arranged or both designed and arranged such that the elastic element is subjected to bending stress when the sealing flap is opened.

7. The retaining plate according to claim 1, wherein one end of the elastic element is connected to the base plate, and a second end rests loosely against the base plate.

8. A vacuum cleaner filter bag comprising a bag wall and a retaining plate according to claim 1, the retaining plate connected to the bag wall.

9. A method of manufacturing a retaining plate for a vacuum cleaner filter bag comprising: providing a base plate having a passage opening and providing a sealing flap for sealing the passage opening; and arranging an elastic element on the base plate or the sealing flap or both the base plate and the sealing flap, wherein the elastic element is arranged in front of the sealing flap when viewed in a sealing direction; wherein the arranging of the elastic member comprises providing a coil spring, which is at least partially enclosed by a sheath.

Description

FURTHER FEATURES AND ADVANTAGES ARE DESCRIBED BELOW USING THE EXEMPLARY FIGURES

(1) Thereby:

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

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

(4) FIG. 3 shows an illustration of the example elastic elements;

(5) FIGS. 4A and 4B show alternative examples of a possible elastic element; and

(6) FIGS. 5A, 5B and 5C show different cross-sections of exemplary elastic elements.

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

(11) FIG. 2 also shows a sealing lip 4 enclosing the passage opening 3. The sealing lip 4 may 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 piece of the vacuum cleaner. However, the sealing lip shown here is only optional. It is also conceivable that the bag material of the vacuum cleaner filter bag itself could be used as a sealing ring, as disclosed, 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 disclosed in EP 2 044 874. It is also possible that no sealing is provided.

(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 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 front of the sealing flap 5 when viewed in the sealing direction. 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, for example, an elastomer element in particular made of a vulcanized silicone elastomer (for example crosslinked liquid silicone rubber (LSR) or crosslinked solid silicone (High-Consistency Rubber, HCR)). 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, for instance, from the vacuum cleaner housing, the force opening the sealing flap 5 ceases to exist, and the sealing flap 5 is returned to the closed position via the elastic element 7.

(15) The elastic element 7 in this example is cylindrical, in particular with a rectangular base (not shown). At position 8, the elastic element 7 is molded onto the base plate of the retaining plate 2. This can be achieved by means of two-component injection molding. If a sealing lip 4 is provided, as in this example, the elastic element 7 and the sealing lip 4 can be molded together on the base plate into one mold. In this case, the elastic element 7 and the sealing lip 4 can be made of the same material.

(16) FIG. 3 shows an alternative elastic element 7 in a schematic representation. In particular, FIG. 3 shows a coil spring 9, which is arranged inside a sheath 10. For illustrative purposes, the sheath 10 is shown in a longitudinal section. In fact, the sheath 10 completely encloses the coil spring 9 radially. In other words, the sheath 10 in this example is formed as a hollow cylinder. Sheath 10 protects the spaces between the coil spring 9 from dirt particles, such that the spring effect is not, or to a lesser extent, impaired by dirt particles. The ends of the sheath 10 can be open, as illustrated in FIG. 3. Alternatively, it is also possible to seal one or both ends of the hollow cylinder so that the coil spring 9 is more or completely shielded from the environment. This prevents the coil spring 9 from being exposed to dirt particles as much as possible.

(17) FIGS. 4A and 4B show alternative possibilities for the sheath 10 of FIG. 3. FIG. 4A again shows a coil spring 9, this time in a top view. The coil spring 9 lies on a film not shown here and is covered by another film 11. The coil spring 9 is therefore located between two films, which are arranged on top of one another. In the example in FIG. 4A, the two films are completely welded together. The weld seams 12 and 13 are arranged on two opposite sides of the films. This creates a cavity or a pocket, in which the coil spring 9 is arranged. This pocket is sealed at the ends by further cross-weld seams. As a result, the coil spring is completely shielded from the environment. The films in this example are plastic films. Welding is carried out by applying a ultrasonic welding technique.

(18) FIG. 4B shows an alternative in which only one film 11 is used, on which the coil spring 9 is first arranged. Part of the film 11 is then folded over the coil spring 9 and two opposite edges of film 11 are joined together with a longitudinal weld seam 12. This in turn creates a cavity or pocket, in which the coil spring 9 is arranged. In the example in FIG. 4B, the ends of this bag are open. However, it would also be possible to seal the two ends with a transverse weld seam, in accordance with FIG. 4A.

(19) FIGS. 5A, 5B and 5C show different cross-sections of an elastic element made of an elastomer. FIG. 5A shows a square cross-section, FIG. 5B shows a circular cross-section, and FIG. 5C shows an annular cross-section. However, other geometries of the cross-section are also conceivable.

(20) 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.