Abstract
The invention relates to a retainer plate for a vacuum cleaner filter bag, comprising at least one sealing element, a base plate in which a passage opening is formed, and a centering device which extends at least partly around the periphery of the passage opening, said centering device having at least one first spring element which, upon deformation in the radial direction, exerts a restoring force directed counter to the deformation.
Claims
1. A retaining plate for a vacuum cleaner filter bag, comprising: a sealing element; a base plate in which a passage opening is formed; and a centering device which extends at least partially along the circumference of the passage opening, wherein the centering device comprises at least one first spring element which, when deformed in a radial direction, exerts a restoring force opposing the deformation.
2. The retaining plate according to claim 1, wherein the at least one spring element is formed from a deformed region of the retaining plate.
3. The retaining plate according to claim 2, wherein the deformed region is wave-shaped.
4. The retaining plate according to claim 3, wherein the deformed region comprises one or more waves arranged concentrically with respect to the passage opening.
5. The retaining plate according to claim 1, wherein the centering device is a diaphragm spring.
6. The retaining plate according to claim 1, wherein the centering device is formed integrally with the base plate.
7. The retaining plate according to claim 1, wherein the retaining plate has at least one radial recess in the region of the centering device.
8. The retaining plate according to claim 1, wherein the centering device further comprises at least one second spring element; wherein the at least one second spring element, when deformed in the radial direction, exerts a restoring force opposing the deformation; and wherein the arrangement of the at least one first and second spring elements has no rotational symmetry with respect to the passage opening.
9. The retaining plate according to claim 1, comprising a thermoplastic and/or a recycled plastic
10. The retaining plate according to claim 9, wherein the retaining plate is thermoformed, a deep-drawn part or an injection-molded part.
11. The retaining cleaner filter bag comprising a retaining plate according to claim 1.
12. A vacuum cleaner filter bag comprising: at least one sealing element; and a retaining plate, wherein the retaining plate comprises: a base plate in which a passage opening is formed; and a centering device which extends at least partially along the circumference of the passage opening, wherein the centering device comprises at least one first spring element which, when deformed in a radial direction, exerts a restoring force opposing the deformation.
13. The vacuum cleaner filter bag according to claim 12, wherein the at least one sealing element is provided in the bag and/or between the bag and the retaining plate.
14. The vacuum cleaner filter bag according to claim 12, wherein the at least one sealing element consists of rubber, TPE, or the material of the vacuum cleaner filter bag.
Description
[0038] Further features of the invention are explained below using the exemplary figures, where
[0039] FIGS. 1a-1c schematically show a conventional retaining plate with vacuum cleaner nozzle in reference position in top view (a), as well as in reference position (b) and under load in a radial direction (c) in sectional view
[0040] FIG. 2 schematically shows the structure of an exemplary vacuum cleaner filter bag;
[0041] FIG. 3 shows a schematic representation of an exemplary mounting plate in top view;
[0042] FIGS. 4a and 4b show a schematic diagram of an exemplary retaining plate in reference position (a) and under load in a radial direction (b) in sectional view; and
[0043] FIGS. 5a-5c show profiles of exemplary centering devices.
[0044] FIG. 1a schematically shows a conventional retaining plate 1 with a passage opening 2 and a sealing element 3 attached to the retaining plate 1 in a top view. A vacuum cleaner nozzle 4 is inserted into the passage opening 2.
[0045] FIG. 1b shows a sectional view of the retaining plate 1 with vacuum cleaner nozzle 4 in reference position. It can be seen that the sealing element 3 completely seals the vacuum cleaner nozzle 4.
[0046] FIG. 1c shows the retaining plate 1 with inserted vacuum cleaner nozzle 4 after a displacement in radial direction, e.g. due to the weight force of suction material contained in a vacuum cleaner bag, which is illustrated by the arrow pointing downwards. The displacement has created a gap 5 between the sealing element 3 and the vacuum cleaner nozzle 4, through which dust can escape from the vacuum cleaner bag into the interior of the vacuum cleaner.
[0047] FIG. 2 shows the schematic structure of an exemplary vacuum cleaner filter bag. The filter bag comprises a bag wall 6, a retaining plate 7 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 8 in the base plate of the retaining plate 7 and an aligned passage opening in the bag wall 6. The retaining plate 7 is used to fix the vacuum cleaner filter bag in a corresponding holder in a vacuum cleaner housing.
[0048] Bag wall 6 comprises at least one nonwoven layer, for example of a meltblown nonwoven or a spunbond nonwoven.
[0049] The retaining plate 7 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.
[0050] For many plastic recyclates there are relevant international standards. For PET plastic recyclates, for example, DIN EN 15353:2007 is relevant.
[0051] The term “recycled plastics” used for the purposes of the present invention is to be understood as synonymous with plastic recyclates. For the conceptual definition, reference is made to the standard DIN EN 15347:2007.
[0052] A top view of an exemplary retaining plate, which can be used in conjunction with a filter bag as shown in FIG. 2, is shown in FIG. 3. This shows the retaining plate 7 with passage opening 8. The base plate of the retaining plate 7 is here illustrated to be schematically rectangular, but it can have any shape, in particular one which may correspond to the corresponding retaining device in the vacuum cleaner housing.
[0053] FIG. 3 also shows a centering device 9 as part of the retaining plate 7, shown here as integrally formed with the base plate of the retaining plate 7, but it can also be a separate element connected to the retaining plate 7 by gluing and/or welding. In FIG. 3, the centering device runs completely around the circumference of the passage opening 8, but it can also be limited to part of the circumference.
[0054] The centering device 9 shown in FIG. 3 comprises four spring elements 10, 11, 12, 13, which are separated from each other by cut-outs 14. In other words, in the embodiment shown in FIG. 3, the centering device 9 consists of the four spring elements 10, 11, 12, 13, but the centering device 9 can also comprise a base plate on which the spring elements are fixed, for example by gluing, screwing or welding. In this case, the spring elements may be separate elements spaced from each other, in particular they may be spaced from each other in the circumferential direction of the passage opening 8. The distances between the spring elements may be equal or different. The number of spring elements is not limited to four, but the centering device 9 always includes at least one spring element.
[0055] In FIG. 3, the spring elements 10, 11, 12, 13 are formed by deformed regions of the retaining plate 7. The deformed regions are formed by alternating elevations and/or depressions, whereby additional flat regions can be arranged between the elevations and/or depressions. In particular, the sequence of deformations repeats itself periodically, with one period forming a wave 15, e.g. if the deformed regions are formed by alternating elevations and depressions, one elevation and an adjacent depression each represent a wave 15.
[0056] In FIG. 3 the spring elements 10, 11, 12, 13 each comprise four waves 15, but the spring elements can have any number of waves 15.
[0057] In the embodiment shown in FIG. 3, the waves 15 form concentric ring structures around the passage opening 8.
[0058] FIG. 3 further shows that the arrangement of the spring elements 10, 11, 12, 13 has no rotational symmetry with respect to the passage opening 8. In particular, the spring element 10 is larger than the spring elements 11, 12 and 13, which also means that the spring force of the spring element 10 is larger than that of the spring elements 11, 12 and 13. If the retaining plate 7 is installed in a vacuum cleaner in such a way that the main load direction of is directed towards the spring element 10, the largest restoring force is achieved in this direction. In FIG. 3, this is illustrated with an arrow indicating the direction of gravity. If gravity acts in the direction of the arrow, spring element 10 is compressed the most by the displacement of the retaining plate 7. Since spring element 10 also has the strongest restoring force, this ensures that the displacement in the main load direction can be compensated.
[0059] The arrangement of the spring elements can also have n-fold rotational symmetry with respect to the passage opening 8, where n is an integer greater than 1. This is advantageous, for example, if there is no main load direction in the plane of the retaining plate 7 during operation of the vacuum cleaner. In particular, this may be the case when the axis of the vacuum cleaner nozzle 4 is substantially parallel to the direction of gravity during operation.
[0060] FIGS. 4a and 4b show a schematic sectional view through the exemplary retaining plate 7 with an inserted vacuum cleaner nozzle 4, analogous to FIGS. 1b and 1c. FIG. 4a and FIG. 4b also show a sealing element 16, which is attached to the inside of the retaining plate 7. In particular, the illustrated sealing element 16 is attached to a spring element, which can be advantageous in order to save material. The sealing element 16 can also be attached to undeformed regions of the retaining plate 7. Furthermore, sealing element 16 can completely cover the spring elements in radial direction when viewed in a top view. This is advantageous, for example, if the spring elements are separated from each other by cut-outs 14. The sealing element 16 can also be attached to the outside of the retaining plate 7.
[0061] The sealing element 16 may comprise a thermoplastic elastomer, e.g., based on polypropylene, or may consist of it. The sealing element 16 is intended 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 8 and the outside of a connection nozzle 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 for example disclosed in DE 102 03 460. It is also possible to use a sealing diaphragm between retaining plate 7 and bag wall 6, as disclosed in EP 2 044 874.
[0062] FIG. 4a shows the retaining plate 7 and the vacuum cleaner nozzle 4 in reference position. It can be seen that the sealing element 16 completely seals the vacuum cleaner nozzle 4.
[0063] FIG. 4b shows the support plate 7 and the vacuum cleaner nozzle 4 under the influence of a force, illustrated by the arrow, which corresponds to the force acting on the support plate 1 in FIG. 1c. FIG. 4b shows that the spring element 10 is deformed when compared to FIG. 4a. Due to this deformation, it exerts a restoring force which is opposite to the acting force. The displacement of plate 7 and the resulting deformation of sealing element 16 is less than in the case illustrated in FIG. 1c, even though the acting force is the same. This means that there is no gap, or a smaller one, between the sealing element 16 and the vacuum cleaner nozzle 4. In other words, the sealing properties of the sealing element 16 are improved by the force acting in a radial direction.
[0064] In the situation illustrated in FIG. 4b, the forces between the spring element and the vacuum cleaner nozzle 4 act indirectly via the sealing element 16, but it is also possible that the vacuum cleaner nozzle 4 is in direct contact with the spring element and the forces act directly between these elements.
[0065] FIG. 5 shows possible designs of spring elements 10, 11, 12, 13 in profile. A wave 15, for example, can be formed by alternating U-shaped elevations and flat regions, as shown in FIG. 5a. Alternatively, they can be formed by alternating U-shaped elevations and U-shaped depressions, as shown in FIG. 5b. In this case, the entire wave has an S-profile. FIG. 5c shows an embodiment in which V-shaped elevations and depressions alternate. However, it is also possible to combine U- and V-shaped elevations with each other and/or flat regions. The elevations and/or depressions need not be pointed or rounded either, but may be flattened at their respective ends.
[0066] It is understood that features described in the embodiments above are not limited to these special combinations and are also possible in any other combination. Further, it is understood that the geometries shown in the figures are only exemplary and can also be designed in any other form.
