Vacuum cleaner filter bag for a handheld vacuum cleaner

Description

[0001] The invention relates to a vacuum cleaner filter bag, in particular a vacuum cleaner filter bag for a handheld vacuum cleaner and / or a so-called stick vacuum cleaner, in particular for cordless models.

[0002] Stick vacuum cleaners are usually, but not always, cordless devices (battery-operated vacuum cleaners) in which an electric brush is connected to the actual housing of the handheld vacuum cleaner via a suction tube without a suction hose. These devices are very lightweight and handy. The sticks have low input power in the range of approximately 150 to 600 W. The achieved flow rates are correspondingly low, in the order of 10 to 30 l / s. The filter housing is typically cylindrical and has a small volume (approximately 1 to 2 liters). A cyclone separator is usually used as the filter. The cyclone separator accelerates the suction air and the particles it contains. This consumes a significant portion of the available power, leaving little power available to generate a sufficient flow rate. The cleaning effect (dust collection) is often unsatisfactory.

[0003] From SE 1 250 019 A1 a holding plate for a vacuum cleaner bag is known which can be reversibly connected to the vacuum cleaner bag, whereby the outer contour of the holding plate can be adapted to the contour of the holding plate present in a vacuum cleaner.

[0004] EP 2 772 173 A1 discloses a filter bag for a vacuum cleaner, wherein a filter material is secured to a plate-shaped part, while a collar is secured to the plate-shaped part within a circular inlet opening. Alternatively, the collar can be connected to the filter material and the plate-shaped part at a single annular seam, thus providing only one connection point.

[0005] A filter bag made of modern nonwoven laminates achieves significantly more energy-efficient dust separation. However, it is difficult to produce a filter bag that fits optimally into the very small available space and provides a sufficient filter surface.

[0006] Traditional flat bags, in which two filter material blanks are welded circumferentially and a retaining plate is bonded flat to one of the filter material blanks, are generally unsuitable because the available installation space is too small. Therefore, bags with a bottom, such as block bottoms, have been used primarily to date. These bags have the retaining plate located at the bottom and the shape of the bag is adapted to the installation space (so-called "three-dimensional" bags). However, producing such bags, especially with a nonwoven material commonly used today, has proven difficult. Therefore, manual production steps are sometimes still required in the manufacture of such bags, which reduces production efficiency.

[0007] The object of the invention is therefore to provide a vacuum cleaner filter bag that can be produced simply and automatically, in particular a vacuum cleaner filter bag for a handheld vacuum cleaner and / or a stick vacuum cleaner, which can make the best possible use of the available installation space.

[0008] This object is achieved by a vacuum cleaner filter bag according to claim 1. Particularly advantageous developments can be found in the subclaims.

[0009] The invention therefore provides a vacuum cleaner filter bag comprising a bag wall and a holding plate, wherein the holding plate comprises a nozzle which is at least partially cylindrical and extends in the direction of the through-opening formed in the holding plate, wherein the bag wall is connected to the outer surface of the nozzle along the circumference of the nozzle.

[0010] Because the bag wall is connected to the retaining plate via the at least partially cylindrical nozzle and to the outer surface of the nozzle along its circumference, the complex, and otherwise often only manually possible, formation of a base during production is eliminated. This allows the vacuum cleaner filter bag according to the invention to be manufactured more efficiently.

[0011] The vacuum cleaner filter bag can be designed specifically for handheld vacuum cleaners and / or so-called stick vacuum cleaners, especially cordless models. The fully expanded capacity can therefore be between 0.5 and 3 liters, and in particular between 0.5 and 2 liters.

[0012] The retaining plate of the vacuum cleaner filter bag can be attached to a retaining device in a vacuum cleaner housing. This allows the retaining plate to be arranged, in particular fixed, in a predetermined position in the vacuum cleaner housing.

[0013] In contrast to a flat bag, in which the holding plate is connected to a flat wall section of the bag wall, in the case of the production of the vacuum cleaner filter bag according to the invention, the bag wall provided with a corresponding opening is slipped over the at least partially cylindrical nozzle of the holding plate and connected to its outer surface. As a result, the vacuum cleaner filter bag extends essentially parallel to the longitudinal axis of the nozzle and thus in the inflow direction through the through-opening of the holding plate into the bag. This also better adapts the vacuum cleaner filter bag to the usual filter housings of handheld vacuum cleaners and / or stick vacuum cleaners, which are typically cylindrical in design and have the holding device for the holding plate on one of the cover surfaces of the cylinder.

[0014] The at least partially cylindrical nozzle thus encompasses the through-opening of the retaining plate, forming an inlet opening through which dust-laden air can flow into the interior of the vacuum cleaner filter bag during operation. The longitudinal axis of the nozzle is defined herein as the direction in which the through-opening in the nozzle extends. This direction is, in particular, perpendicular to the plane in which a connecting plate of the retaining plate is arranged, which can be connected to a holding device of the vacuum cleaner.

[0015] "At least partially cylindrical" means that the nozzle comprises at least one section that is shaped like a cylinder, i.e., defined by a lateral surface and two boundary surfaces. The cylindrical shape is not limited to a circular cylinder. The cross-section of the cylindrical section, i.e., the directrix of the general cylinder, can be of any shape. The cross-section of the cylindrical section can also be a polygon. In this case, one can also speak of a prism-shaped section. The cylindrical section can, in particular, have the shape of a straight or vertical cylinder, with the generatrices running parallel to the longitudinal axis of the nozzle.

[0016] The nozzle may comprise a second section, particularly adjacent to the cylindrical section, with a larger circumference than the cylindrical section. The second section may, in particular, protrude outward beyond the outer surface of the cylindrical section. This second section may correspond to the connecting plate of the retaining plate or be part of it.

[0017] The connecting plate can, in particular, be a flat component, in particular wherein its extension in two directions (length, width) is significantly larger, in particular at least three times larger, than in a direction perpendicular thereto (thickness). The connecting plate can, in particular, completely surround the through-opening of the retaining plate. The through-opening of the retaining plate can, in particular, extend through the connecting plate and the connecting piece.

[0018] The retaining plate may comprise or consist of one or more plastics. In particular, recycled plastics such as recycled polypropylene (rPP) and / or recycled polyethylene terephthalate (rPET) may be used.

[0019] The retaining plate can include a closure element for closing the inlet opening. This allows the suction material to be retained inside the bag, especially when removing the bag.

[0020] The retaining plate is formed integrally with the nozzle. The retaining plate and nozzle are thus a single component.

[0021] The retaining plate can be formed as an injection-molded part or as a part produced by thermoforming. The retaining plate can also be manufactured partly by injection molding and partly by thermoforming.

[0022] The retaining plate may also include a sealing lip surrounding the through-opening. The sealing lip may comprise or be made of a thermoplastic elastomer, for example, based on polypropylene. The sealing lip 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 through-opening and the outside of a vacuum cleaner connection piece.

[0023] The bag wall is made of an air-permeable material and can be constructed in multiple layers. In this case, this is also referred to as a laminate. Several layers of the laminate, in particular each layer of the laminate, can comprise or consist of a nonwoven fabric and / or a nonwoven fabric.

[0024] A wide variety of plastics, such as polypropylene and / or polyester, can be used as the material for the bag wall, especially for one or more layers of nonwoven or nonwoven fabric. The bag wall can also include or consist of recycled plastic and / or recycled material from the production of textiles (textile leftovers - TLO).

[0025] Relevant international standards exist for many plastic recyclates. For PET plastic recyclates, for example, DIN EN 15353:2007 is relevant. PP recyclates are characterized in DIN EN 15345:2008. For the purpose of the corresponding specific plastic recyclates, this patent application adopts the definitions of these international standards. The plastic recyclates can be unmetallized. One example of this is plastic flakes or chips recovered from PET beverage bottles. The plastic recyclates can also be metallized, e.g., if the recyclates were obtained from metallic plastic films, particularly metallized PET films (MPET).

[0026] Recycled polyethylene terephthalate (rPET) can be obtained, for example, from beverage bottles, in particular from so-called bottle flakes, i.e. pieces of ground beverage bottles.

[0027] The recycled plastics, in particular recycled PET and / or recycled PP, both in the metallized and non-metallized form, can be spun into the corresponding fibers from which the corresponding staple fibers or meltblown or spunbond nonwovens can be produced for the purposes of the present invention.

[0028] Recycled material from textile production (TLO) arises primarily during the processing of textile materials (especially textile fibers and filaments, as well as linear, sheet-like, and three-dimensional textile structures produced with them), such as during the manufacturing (including carding, spinning, cutting, and drying) or recycling of textile materials. These powdered and / or fibrous materials represent waste materials that can settle on the machines or filter materials used to process the textiles. The dust (powder) or fibers are usually disposed of and thermally recycled.

[0029] The powdered and / or fibrous recycled material, for example, is considered production waste; this applies in particular to material that arises as a waste product during the carding, spinning, cutting, or drying of textile materials. In this case, it is also referred to as "pre-consumer waste."

[0030] The recycling of textile materials, i.e. the processing (e.g., shredding) of used textile materials or textiles (e.g., old clothes), also produces powdered and / or fibrous recycled material; this is referred to as "post-consumer waste."

[0031] The recycled material from the manufacture of textiles, TLO, may therefore include, in particular, fibres and / or filaments obtained from waste materials from the textile and clothing industry, from post-consumer waste (textiles and similar) and / or from products collected for recycling.

[0032] For the purposes of the present invention, a nonwoven fabric refers to a randomly arranged fabric that has undergone a bonding step, so that it has sufficient strength to be wound or unwound into rolls, for example, mechanically (i.e., on an industrial scale). The minimum web tension required for winding is 0.044 N / mm. The web tension should not exceed 10% to 25% of the minimum maximum tensile force (according to DIN EN 29073-3:1992-08) of the material being wound. This results in a minimum maximum tensile force for a wound material of 8.8 N per 5 cm strip width.

[0033] A nonwoven fabric, or simply "fleece" for short, corresponds to a randomly arranged fabric that has not undergone a consolidation step, so that, in contrast to a nonwoven fabric, such a randomly arranged fabric does not have sufficient strength to be wound or unwound into rolls by machine, for example.

[0034] In other words, the term "nonwoven" is used according to the definition in ISO Standard ISO9092:1988 or CEM Standard EN29092. Details on the use of the definitions and / or procedures described herein can also be found in the standard reference "Nonwovens," W. Albrecht, H. Fuchs, W. Kittelmann, Wiley-VCH, 2000.

[0035] The nonwoven layers of the bag wall can, in particular, comprise a staple fiber nonwoven and / or an extrusion nonwoven. In particular, filament spunbond nonwovens (also referred to as "spunbond" or "spunbond" for short) and / or meltblown nonwovens can be used.

[0036] One or more layers of the bag wall can comprise a carded material. Both mechanical processes (e.g., needling) and thermal processes (e.g., calendering) can be used for the binding step. Binding fibers or adhesives, such as latex adhesive, are also possible. Airlaid materials are also possible.

[0037] The nonwoven fabric of one or more layers of the bag wall can comprise bicomponent fibers. Bicomponent fibers (BiCo fibers) can be formed from a core and a sheath surrounding the core. In addition to core / sheath bicomponent fibers, other common variants of bicomponent fibers, such as side-by-side, can also be used.

[0038] The bicomponent fibers can be present as staple fibers or as filaments in an extrusion nonwoven fabric (e.g. meltblown nonwoven fabric).

[0039] As mentioned, correspondingly unconsolidated fiber fleeces are also conceivable.

[0040] The nonwoven fabric of one or more layers of the bag wall can also have a micro crimp (Micrex).

[0041] The bag wall may also include an odor absorbent.

[0042] The bag wall may, in particular, comprise a capacitance layer. A capacitance layer provides high resistance to impact loading and enables the filtration of large dirt particles, the filtration of a significant proportion of small dust particles, and the storage or retention of large quantities of particles while allowing air to flow through easily, thus resulting in a low pressure drop at high particle loads.

[0043] The bag wall can also include a fine filter layer. A fine filter layer serves to increase the filtration performance of the multi-layer filter material by capturing particles that, for example, pass through the capacitance layer. To further increase the separation performance, the fine filter layer can preferably be electrostatically charged (e.g., by corona discharge or hydrocharging), in particular to increase the separation of fine dust particles.

[0044] The fine filter layer can be connected to the capacity layer, particularly towards the outside of the bag wall.

[0045] A support layer can be attached to the fine filter layer. A support layer (sometimes also called a "reinforcement layer") is a layer that provides the necessary mechanical strength to the multi-layer composite of the filter material. The support layer can be, in particular, an open, porous nonwoven fabric with a light basis weight. The support layer can, in particular, be a spunbonded nonwoven fabric.

[0046] However, it is also possible to use a single-layer filter material for the bag wall. In this case, it can be a meltblown nonwoven fabric. A suitable material for such a single-layer bag wall is known, for example, from EP 2 311 360 B1.

[0047] The bag wall can be connected, in particular, to the outside of the nozzle, i.e., the side facing away from the nozzle's through-opening. This allows for advantageous optical control of the fastening process during production, particularly visually and / or via automated image processing.

[0048] The length of the side of the bag wall connected to the nozzle can, in particular, correspond to the outer circumference of the cylindrical section of the nozzle. In particular, the bag wall can be connected to the outer surface of the nozzle along the entire circumference of the nozzle. Both the bag wall and the outer surface of the cylindrical section of the nozzle thus completely surround the through-opening of the nozzle.

[0049] The bag wall can be glued or welded to the outer surface, and / or the bag wall can be clamped between the outer surface and a clamping element. The clamping element can, in particular, be a hollow cylinder. In this case, it can also be referred to as a clamping ring. Fastening solely via a clamping element enables a detachable connection and thus reuse of the retaining plate and nozzle.

[0050] The retaining plate can be arranged on a short side of the bag wall. In other words, the longitudinal axis of the vacuum cleaner filter bag can extend parallel to the longitudinal axis of the nozzle.

[0051] The bag wall can have a surface pleat with at least five folds. The surface pleats of the filter medium offer significant advantages. Due to the surface pleats, the area through which the filter media passes is significantly larger than the area normally available for flow (inflow area). In other words, the surface pleats allow the bag wall to be at least partially pleated.

[0052] The term fold is defined in the sense of the present invention as a sequence of two or more folds, wherein a single fold in the sense of the present invention is defined by two fold legs and one fold hinge.

[0053] A surface fold is a sequence of folds provided on the bag wall. Such a surface fold is at most secured by a portion of the seam along a side edge. However, this portion of the seam is neither a fold hinge nor a component of the fold leg of one of the folds in the fold.

[0054] The vacuum cleaner filter bag, in particular its bag wall, can also comprise at least one side fold.

[0055] A side fold is a sequence of folds along the side edge of a vacuum cleaner filter bag. The seam along the side edge of the vacuum cleaner filter bag is part of one of the folds forming the side fold; for example, the seam along the side edge is a fold hinge, or the seam lies almost entirely within a fold leg.

[0056] The at least five folds of the surface pleats can run along the longitudinal axis of the filter bag. Alternatively, the folds can also run perpendicular to the longitudinal axis.

[0057] A fixing device may also be provided which prevents at least one of the at least five folds from unfolding completely.

[0058] The folds of a bag wall can be at least partially connected to one another by means of a fixing device. The fixing device can also keep the folds of the bag wall at a predetermined distance from one another.

[0059] The fixing device can comprise at least one material strip, in particular a nonwoven material strip, or consist of at least one material strip, in particular at least one nonwoven material strip. Several material strips can be arranged at a distance from one another or directly adjacent to one another.

[0060] Several material strips can run transversely, in particular perpendicularly, or at a predetermined angle to the longitudinal direction of the folds. The predetermined angle can be greater than 0° and less than 180°, in particular greater than 30° and less than 150°.

[0061] The fixing device is preferably arranged on the upstream side of the bag wall. "Upstream side" here means facing the interior of the vacuum cleaner filter bag. The fixing device can be at least partially connected to the bag wall, in particular to the folds of the bag wall, in particular directly connected, in particular glued and / or welded. Furthermore, the fixing device can be glued and / or welded at points where the fold legs of two different folds of the bag wall adjoin one another.

[0062] The fixing device can be glued and / or welded to the bag wall in one or more areas of the bag wall, each located between two folds of the bag wall. This allows for simple production of the vacuum cleaner filter bag, particularly with horizontal folds that do not overlap.

[0063] Two or more folds of the bag wall may also be connected to each other by the fixing device, while two or more folds of the bag wall may not be connected to each other by the fixing device.

[0064] Alternatively or additionally, the fixing device can be glued and / or welded to one or more folds of the bag wall in such a way that the connection separates during operation of the vacuum cleaner filter bag. Thus, the airflow within the vacuum cleaner filter bag can be influenced by the at least partially releasing fixing device.

[0065] In other words, parts of the fixing device can serve as air distributors during operation of the vacuum cleaner filter bag.

[0066] The surface folds, side folds and / or fixing devices can be designed in particular as described in European patent application EP 2 366 319 or European patent application EP 2 366 320.

[0067] The side of the bag wall opposite the retaining plate can be concave or convex. This allows for better use of the installation space.

[0068] The invention also provides a method for producing a vacuum cleaner filter bag according to claim 10, in particular for producing a vacuum cleaner filter bag as described above. The method according to the invention thus comprises the following steps: a) Forming a tubular bag of filter material that is open on one side; b) Arranging a holding plate comprising an at least partially cylindrical nozzle at the wide end of a conical guide element, such that the nozzle of the holding plate rests against the outer surface of the conical guide element; c) Slipping the bag over the conical guide element; d) Connecting the bag to the outer surface of the nozzle facing away from the guide element; and e) Lifting the bag connected to the nozzle off the guide element.

[0069] This process allows for efficient and automated production.

[0070] Forming the tubular bag, open on one side, may comprise overlapping two filter material webs and forming two longitudinal and one transverse weld seams. Alternatively, forming the tubular bag, open on one side, may comprise folding over a single filter material web and forming a longitudinal weld seam for connecting two edges of the filter material web that overlap after folding over, as well as forming a transverse weld seam.

[0071] Forming the tubular bag open on one side may also include forming the surface fold and / or side fold described above.

[0072] The surface pleats can be introduced, in particular, along the conveying direction of the filter material web. If the pleats are to run along the longitudinal direction of the vacuum cleaner filter bag, the open side is arranged transversely to the conveying direction of the filter material web. If the pleats are to run transversely to the longitudinal direction of the vacuum cleaner filter bag, the open side is arranged in the conveying direction of the filter material web.

[0073] The conical guide element can be arranged on a work table, in particular a rotary table. In particular, several conical guide elements can be provided, in particular along the circumference of the rotary table. The radius of the conical guide element can decrease, in particular, away from the surface of the work table.

[0074] The conical guide element can be designed so that its diameter can be changed or adjusted on the surface of the work table. For example, the conical guide element can be arranged in a through hole in the work table and can be moved perpendicular to the surface of the work table. Alternatively, the conical guide element can be formed from several radially movable elements.

[0075] Arranging the holding plate with the at least partially cylindrical connecting piece at the wide end of a conical guide element can comprise slipping the holding plate over the conical guide element. The inner diameter of the at least partially cylindrical connecting piece, i.e., the diameter of its above-mentioned through-opening, can correspond to the outer diameter of the conical guide element on the surface of the work table, so that the connecting piece rests against the outer surface of the conical guide element. For this purpose, the conical guide element can have a cylindrical section at its wide end, the shape and extent of which correspond to the shape and extent of the cylindrical section of the connecting piece, but the outer radius of the cylindrical section of the conical guide element corresponds to the inner diameter of the cylindrical section of the connecting piece.

[0076] Slipping the bag over the conical guide element can involve gripping and opening the tubular bag, which is open on one side. Slipping the bag over the conical guide element can be performed, in particular, in an automated manner by a robot gripper.

[0077] If the folds are perpendicular to the longitudinal direction of the vacuum cleaner filter bag, the open side of the bag is positioned in the conveying direction of the filter material web. In this case, the robot gripper rotates the bag before placing it over the conical guide element.

[0078] If the vacuum cleaner filter bag is pleated longitudinally, the open side of the bag is positioned perpendicular to the conveying direction of the filter material web. In this case, the robot gripper can pick up the bag in the conveying direction of the filter material web and place it over the conical guide element.

[0079] The bag can be connected to the outer surface of the nozzle facing away from the guide element, particularly by ultrasonic welding. The conical guide element forms the anvil for the sonotrode. The welding process can be performed in several steps. For example, a turntable can be used to move the conical guide element with the bag placed over it to different welding stations, which are arranged and designed to weld different segments of the circumference of the nozzle to the bag wall. Alternatively, a circumferentially movable welding sonotrode can also be used.

[0080] Alternatively or additionally, the connection of the bag to the outer surface of the nozzle facing away from the guide element can comprise arranging a clamping element above the bag wall, so that the bag wall is clamped in a region of the outer surface of the nozzle between the outer surface of the nozzle and the clamping element.

[0081] The lifting of the bag connected to the nozzle from the guide element can, in turn, be automated using a robot gripper. Lifting the bag connected to the nozzle from the guide element can also involve reducing the diameter of the conical guide element on the surface of the work table, for example, by lowering the conical guide element into a through hole in the work table.

[0082] The method may further comprise a visual inspection of the connection between the bag wall and the outer surface according to step d). In particular, at least one digital image of the connection area between the bag wall and the outer surface can be generated. This digital image can be subjected to automated image processing to detect defects in the connection, for example, inadequately formed weld seams. Based on the detection of an inadequate connection, a warning signal can be issued and / or the bag in question can be rejected.

[0083] Further features and advantages of the invention are described below with reference to the exemplary figures. Herein: Figure 1 shows a cross-section through an exemplary vacuum cleaner filter bag; Figure 2 shows a perspective view of an exemplary holding plate with a nozzle that is at least partially cylindrical; Figure 3 shows a plan view of an exemplary tubular bag, open on one side, for producing a vacuum cleaner filter bag; Figure 4 shows a perspective view of an exemplary conical guide element for producing a vacuum cleaner filter bag; and Figure 5 shows an illustration of a manufacturing step in the production of an exemplary vacuum cleaner filter bag.

[0084] Figure 1 shows a cross section through an exemplary vacuum cleaner filter bag 1 with a bag wall 2 and a holding plate 3. The holding plate 3, in particular its flat connecting plate, serves to fix the vacuum cleaner filter bag 1 in a corresponding holder in a housing of a vacuum cleaner.

[0085] The bag wall is not directly connected to the flat part of the holding plate 3, i.e., the connecting plate, as is usual in the prior art, but rather to a connecting piece 4 of the holding plate 3, which is at least partially cylindrical. In particular, the connecting piece extends in the direction of the through-opening 5 formed in the holding plate 3, i.e., perpendicular to the plane in which the connecting plate lies. The bag wall 2 is connected along the circumference of the connecting piece 4 to its lateral surface, which also extends in the direction perpendicular to the connecting plate.

[0086] Figure 2shows a perspective view of an exemplary holding plate with a nozzle 4 that is at least partially cylindrical. The nozzle 4 comprises a cylindrical section. The shape of the cylindrical section can be freely selected and is not limited to the shape of a circular cylinder. The axis of the cylindrical section defines the longitudinal axis of the nozzle 4. The through-opening of the holding plate is provided along this longitudinal axis of the cylindrical section. This forms an inflow opening for the suction material into the filter bag, as in Figure 1 to see.

[0087] The exemplary holding plate 3 of the Figure 2comprises a second section 8, adjacent to the cylindrical section, with a circumference that is larger than the cylindrical section. The second section 8 projects radially outward beyond the lateral surface of the cylindrical section. This second section 8 can correspond to the connecting plate, as shown in Figure 1 shown.

[0088] The bag wall 2 is in the embodiment of the Figure 1 welded to the outer surface of the cylindrical section of the nozzle 4. The ultrasonic weld seams 6 are particularly visible. Additionally, this exemplary embodiment shows a clamping ring 7, which clamps the bag wall 2 to the outer surface of the cylindrical section of the nozzle 4. Such a clamping ring 7 can also establish the connection between the bag wall and the outer surface on its own.

[0089] Not shown here, a sealing lip can also be provided on the through opening 5.

[0090] Figure 3 shows a plan view of an exemplary tubular bag open on one side, as used in the manufacture of a vacuum cleaner filter bag according to Figure 1 The bag wall 2 of the exemplary bag of the Figure 3 comprises two longitudinal welds 12, 13 and one transverse weld 14. On the transverse side 15 the bag is open, i.e. without a weld, in order to connect it with a nozzle as in Figure 2 to enable shown as an example.

[0091] The transverse weld seam 14 could also be concavely or convexly curved to better utilize the available space. A base, such as a block base, or a side fold would also be conceivable in the area of ​​the transverse weld seam 14.

[0092] In addition, the bag wall 2 includes Figure 3several surface folds 16 running along the longitudinal weld seams 12, 13. At the open end 15, the folds are fixed in position by a fixing device 17.

[0093] As already explained above, the term fold in the sense of the present invention is defined as a sequence of two or more folds, wherein a single fold in the sense of the present invention is defined by two fold legs and one fold hinge.

[0094] A pleat hinge is the point on a fold with the smallest radius of curvature. The imaginary connection of the pleat hinges creates a so-called pleat axis. The pleat axis is also called the crest of the fold. The pleat axis can correspond to the longitudinal axis of a fold. Areas of a fold with a radius of curvature greater than the minimum radius of curvature of the fold are called pleat limbs. The area between the pleat limbs of a fold is called the pleat core. The pleat limbs of a fold can therefore also exhibit a curvature.

[0095] Folds can also have inflection points. Inflection points are those points on a fold, especially the fold limbs, where the curvature of the fold changes from concave to convex. A connecting line connecting several inflection points of a fold is called an inflection line.

[0096] Two adjacent pleats can also share a pleat leg. If several pleats are planned in this way, a pleat set or a pleat train can be created.

[0097] Several folds can also be arranged in a zigzag shape.

[0098] Folds can also have legs that run parallel to the bag wall. Such legs can be located between folds that protrude from the bag wall plane and thus have an upstream opening relative to the bag wall. In particular, the width of the parallel leg can be less than, preferably less than half, or most preferably less than a quarter of, the width of the opening of the fold protruding from the bag wall.

[0099] The fold limbs can, in particular, be smooth. "Smooth" here means that the fold limbs do not have any compaction and / or structuring, particularly those intended to stabilize the shape of the folds.

[0100] One or more pleat legs of one or more pleats may comprise one or more embossed structures, in particular, wherein the embossed structures do not serve to stabilize the shape of the pleats. This can further increase the area available for filtration.

[0101] The bag wall 2 can in particular have more than 5, 10, 20, 30, 40 or 50 folds, in particular also folds of these folds.

[0102] The folds of the bag wall may have a substantially regular spacing from one another. In other words, the distance between the fold ridges of any two adjacent folds may be substantially constant.

[0103] Folds can be horizontal or vertical. Horizontal folds are folds whose fold legs are arranged substantially parallel to the bag wall 2. Vertical folds are folds whose fold legs form an angle greater than 0° and less than 180°, in particular greater than 20° or greater than 45°, with the bag wall 2.

[0104] A vertical fold is also understood to mean a fold in which a plane containing both the fold axis and the inflection line of the fold forms an angle greater than 45°, in particular greater than 30°, in particular greater than 10°, with a flat, horizontal surface on which the first and / or second bag wall is arranged. In this case, a horizontal fold can be understood to mean a fold in which the plane forms an angle of less than 45°, in particular less than 30°, in particular less than 10°, with this surface.

[0105] To measure or determine the above-mentioned angles, the vacuum cleaner filter bag, in particular the folded nonwoven material, is placed on a flat, horizontal surface. For this purpose, the vacuum cleaner filter bag can also be cut open and, in particular, placed on the surface in such a way that the upstream side or inner side of the original vacuum cleaner filter bag rests on the surface.

[0106] Lying folds can be mutually overlapping, non-overlapping and / or partially overlapping.

[0107] To produce an example vacuum cleaner filter bag as shown in Figure 1 As shown, it is necessary to connect the bag wall 2 to the nozzle 4. Although the nozzle 4 made of plastic has a certain strength, in the case of a connection by welding it is advantageous if an anvil is provided which forms an abutment. Figure 4shows such an anvil in the form of a conical guide element 18.

[0108] As in Figure 5 As shown, the conical guide element 18 can be arranged vertically on a work table. The conical guide element 18 is designed such that its outer diameter at the wide end corresponds to the inner diameter of the cylindrical section of the nozzle 4. The holding plate 3 with the nozzle 4 is then Figure 5 shown over the conical guide element 18. A robot gripper can then pick up a tubular bag open at one side, such as in Figure 3shown, and also place it over the conical guide element 18. The conical shape of the guide element 18 is also advantageous here. The bag wall 2 can then be welded to the outer surface of the cylindrical section of the nozzle 4, from the outside. The latter has the advantage that the welding result can be monitored, for example, via image processing.

[0109] Finally, the holding plate 3 and the bag wall 2 connected to it are pulled off the conical guide element 18.

[0110] It is understood that the features mentioned in the previously described embodiments are not limited to these specific combinations and are also possible in any other combinations. Furthermore, it is understood that the geometries shown in the figures are merely exemplary and are also possible in any other configurations.

Claims

1. A vacuum cleaner filter bag (1) comprising a bag wall (2) and a holding plate (3), wherein the holding plate (3) comprises an at least partially cylindrical connecting piece (4) extending towards the through opening (5) formed in the holding plate (3), characterized in that the bag wall (2) is connected to the outer surface of the connecting piece (4) along the circumference thereof, and wherein the bag wall (2) is bonded or welded to the outer surface.

2. The vacuum cleaner filter bag according to claim 1, wherein the bag wall (2) is clamped between the outer surface and a clamping element (7).

3. The vacuum cleaner filter bag according to claims 1 or 2, wherein the connecting piece (4) and the holding plate (3) are formed integrally.

4. The vacuum cleaner filter bag according to any one of the preceding claims, wherein the holding plate (3) and the connecting piece (4) are arranged on a short side of the bag wall (2).

5. The vacuum cleaner filter bag according to any one of the preceding claims, wherein the bag wall (2) includes a surface pleat (16) having at least five individual pleats.

6. The vacuum cleaner filter bag according to claim 5, wherein the at least five individual pleats extend along the longitudinal axis or transversely to the longitudinal axis of the filter bag (1).

7. The vacuum cleaner filter bag according to claims 5 or 6, wherein a fixing device (17) is provided which prevents at least one of the at least five individual pleats from unfolding completely.

8. The vacuum cleaner filter bag according to any one of the preceding claims, further comprising at least one side gusset.

9. The vacuum cleaner filter bag according to any one of the preceding claims, wherein the side of the bag wall (2) opposite the holding plate is formed to be concave or convex.

10. A method for manufacturing a vacuum cleaner filter bag, in particular according to any one of the preceding claims, comprising the following steps: a) forming a tubular bag of filter material open on one side; b) arranging a holding plate comprising an at least partially cylindrical connecting piece (4) at the wide end of a conical guiding member (18) so that the connecting piece (4) of the holding plate (4) abuts against the outer surface of the conical guiding member (18); c) putting the bag over the conical guiding member (18); d) bonding or welding the bag to the outer surface of the connecting piece (4) facing away from the guiding member (18); and e) lifting the bag connected to the connecting piece (4) off the guiding member (18).