Method for manufacturing a brush and intermediate product for performing the method

Abstract

A method for manufacturing a brush, the brush comprising a bristle carrier (10) having prefabricated holes (48) and bristle tufts (50), the method proposes that the holes (48) have a protrusion (100). The bristle tufts (50) receive a thickening (44) which is pushed behind the protrusion (100). Subsequently, the periphery (60) of the holes (48) is plastically shaped so that the holes narrow in this region. Furthermore, an intermediate product for carrying out the method is proposed.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a brush, the brush comprising a bristle carrier having at least one pre-formed hole and a bristle bundle for each hole, wherein the hole or each hole has a laterally limiting hole and an inner wall and a periphery surrounding the hole at the front side of the bristle carrier. Furthermore, the invention also relates to an intermediate product, which is further processed into a brush by means of the method according to the invention. Background Technology

[0002] The brushes are implanted with bristles in different ways.

[0003] The most common and widely used method for securing a bristle bundle in a designated hole is to use so-called anchors. For this purpose, the bristle bundle is folded into a U-shape, and the anchor is located at the so-called end section, i.e., at the end where the ends of the bundle connect to each other. The anchor, along with the folded bristle bundle, is inserted into the hole via a tack tongue and cuts into the hole wall to finally anchor it therein. Therefore, the bundle can no longer be pulled out of the hole.

[0004] Another type of bristle implantation involves heating all the bristles of the bundle at the end, while the bundle remains undisturbed and they are brought together to form a droplet. The thickened end is then anchored in a hole, for example, by shaping the periphery.

[0005] Finally, another variation exists in which the bristle bundles are inserted through through-holes in a small plate or bristle carrier and protrude slightly from the back side of the plate or bristle carrier. The protruding sections are then melted, causing the bristles to blend into each other. Soft plastic is flattened on the back side of the small plate or bristle carrier by a punch, forming a plate composed of molten bristle material when multiple bristle bundles are melted simultaneously. The resulting unit is then encapsulated, for example, by injection molding on the back side. Summary of the Invention

[0006] The object of this invention is to obtain another manufacturing method that can be performed in a very cost-effective manner. Furthermore, it provides an intermediate product for performing the method according to the invention, by means of which the method can be performed particularly easily and quickly.

[0007] This objective is achieved by a method of manufacturing a brush, the brush comprising a bristle carrier having at least one pre-formed hole and a bristle bundle for each hole, wherein the hole or each hole has a laterally limiting hole with an inner wall and a periphery surrounding the hole at the front side of the bristle carrier. The method is characterized by the following steps:

[0008] A bristle carrier is provided in which the wall of one or more holes to be filled has at least one protrusion inside at a distance from the bottom of the hole, which reduces the cross-sectional area of ​​the hole, such that an undercut is formed between the protrusion and the bottom.

[0009] The bristle bundle is folded into a U-shape, the bristle bundle having an arc-shaped end section, a bundle end with a free end starting from this end section and the end section connecting the bundle ends, wherein a thickening member is introduced between the bundle ends in the U-shaped end section, and all the bristles of the disposed bristle bundle extend around this thickening member.

[0010] The bristle bundle and its thickener are pushed so deeply into the hole that the thickener is positioned between the bottom and the protrusion, which prevents the thickener from being pulled out.

[0011] Then, under pressure, the periphery is plastically shaped such that the cross-section of the hole at the periphery is reduced to at least 70% of its initial cross-section, and the area between the hole and the thickener is thus flanged, and the thickener is located in an undercut formed between the flange and the bottom, wherein the flange mechanically blocks the thickener and the bristle bundle to prevent them from being pulled out.

[0012] The method according to the invention prevents the bristle bundle from being incorrectly or suboptimally positioned during subsequent peripheral forming. This means that after the bristle bundle is pushed in, it is pre-positioned by a protrusion. The bristle bundle can no longer be removed from the hole or can no longer be removed from the hole on its own, causing it to become, for example, too close to the periphery, and then laterally deformed during forming.

[0013] The first two steps do not necessarily need to be performed in the order shown, but can be performed in reverse order or simultaneously. Of course, the protrusions do not generate the pull-out force that occurs immediately after plastic forming. However, this fixation by the protrusions before forming is sufficient to prevent axial displacement at the thickened part when processing the unit consisting of the bristle carrier and the inserted bristle bundles, even if, for example, the tool used for pushing in is withdrawn again. However, after forming, the bristle bundles, or in several cases all the bristle bundles, are firmly held in the bristle carrier, so that they can no longer be pulled out of the holes during normal use and under specified frame conditions.

[0014] During plastic forming, the protrusion is also preferably formed, i.e., the protrusion becomes part of the flange, which reduces the cross-section of the hole at the edge of the hole. This means that the protrusion is located in the axial region where the flange will later be located.

[0015] The cross-section of the thickened part is adapted to the cross-section of the hole in the raised area and between the raised and bottom sections, thereby providing a pull-out force between 5N and 14N prior to plastic forming. This pull-out force is insufficient to negate subsequent forming, as in the case of a toothbrush, for example, a pull-out force of 20N or greater must be achieved so that the bristle bundles or individual filaments cannot be pulled out of the hole during use. However, the specified force range is sufficient and optimal to, on the one hand, enable rapid insertion of the unit consisting of the bristle bundles and the thickened part against the not-too-high resistance in the raised area, and on the other hand, ensure that it is sufficiently well positioned in the hole until forming and during forming.

[0016] The thickened part can be abutted against the wall before plastic forming, which improves positioning and slightly increases pull-out force. Alternatively or additionally, the thickened part can be axially received in the hole with a clearance between the bottom and the protrusion, meaning that no or no significant axial load is applied to the bristle tufts in the area of ​​the bottom-shaped end section. Strong axial forces acting on the bristle tufts in this area increase the risk of the filaments becoming irregularly oriented relative to each other. However, minimal axial clamping can also be made between the bristle tufts and the protrusion in the area of ​​the end section, by which the end section is reliably positioned without disrupting the filaments' relative orientation.

[0017] A protrusion is, for example, a closed, surrounding contraction, i.e., an annular contraction of a hole.

[0018] The periphery can be formed such that the resulting flange is kept at a distance from the bottom relative to the axial length of the thickened part, allowing the thickened part to be received between the bottom and the flange in the axial direction with little or no tension. The advantages mentioned above are obtained from this variation.

[0019] Plastic deformation can optionally be achieved by heating the periphery, particularly by using a heated punch that also receives at least one bristle bundle. This punch can also feed all the bristle bundles into the bristle carrier in their own receiving openings, guide them, and plastically shape the periphery around the respective holes. Preferably, this should not be interpreted in a limiting way, but rather that the interior of the hole is not preheated when the bristle bundles are inserted, but rather kept at room temperature. This ensures that sufficient space is left for the bristle bundles in the bottom region of the hole, the bristles remain parallel and oriented, and only the upper portion of the hole deforms in the peripheral region.

[0020] Alternatively, plastic deformation can be achieved by heating and deforming using a punch, or by using an ultrasonic oscillator positioned at the periphery to heat the bristle carrier in that area and apply pressure. This ultrasonic oscillator is typically used only for a single bristle bundle and deforms it within the bristle carrier, ensuring that not all peripheries undergo simultaneous plastic deformation.

[0021] A third possibility for forming is to use a punch that deforms the periphery through a single impact. This punch is preferably at room temperature and therefore not heated as it moves against the periphery.

[0022] The bristle carrier is typically made of plastic, as are the thicker parts. In particular, the bristle carrier and the thicker parts are often made of the same plastic, which has the advantage of being recyclable. An alternative is to manufacture finished parts from paper or cardboard.

[0023] Viewed in the longitudinal section through the hole, the protrusion extends inward only 0.05 mm to 0.2 mm relative to the adjacent wall area. This means that the cross-section in this area is reduced by 0.1 mm to 0.4 mm. However, this minimal protrusion is sufficient to hold the thickened part along with the bristle bundle. The thickened part should, in turn, be at most 0.05 mm smaller or slightly larger than the cross-section of the hole between the protrusion and the bottom.

[0024] To create the protrusion, and to allow the bristle bundles to be inserted together with the thickener, it is advantageous that the protrusion extends continuously and without steps inward from the periphery to the innermost point of the protrusion, and then extends continuously and without steps outward again, transitioning into the rest of the wall. In a longitudinal section view, this results in an arcuate profile.

[0025] The thickened part shall have an axial length that corresponds at most to half the maximum depth of the provided, non-plastically deformed hole, such that there is still sufficient axial length of the hole in which a flange can be formed, and the flange shall not press against or significantly press against the thickened part.

[0026] Advantageously, the hole remains undeformed in the bottom region during peripheral plastic forming, so that no force is applied to the bristle bundles there.

[0027] As already mentioned, the bristle carrier should be at room temperature when at least one bristle bundle is pushed in, that is, it should not be heated or melted.

[0028] The walls of the hole can be cylindrically formed between the protrusion and the bottom and / or between the protrusion and the periphery. In particular, except for the protrusion, the walls of the hole are cylindrically formed, that is, they have the same size and geometry from the bottom region to the peripheral wall region. However, the invention is not limited to cylindrical hole geometries; on the contrary, elliptical and extremely elongated hole geometries can also be achieved.

[0029] The above objective is also achieved by an intermediate product for implementing the method according to the invention, the intermediate product comprising:

[0030] A bristle carrier having at least one pre-formed hole having a laterally defined aperture and an inner wall and a periphery surrounding the hole at the front side of the bristle carrier, wherein the wall of one or more holes to be filled has at least one protrusion inside at a distance from the bottom of the hole, reducing the cross-sectional area of ​​the hole, the protrusion reducing the cross-sectional area of ​​the hole along the axial section, such that an undercut is formed between the protrusion and the bottom.

[0031] The bristle bundle is a U-shaped folded bristle bundle, or, in the case of multiple holes, a U-shaped folded bristle bundle located in each hole, the bristle bundle having an arc-shaped end section, the bundle end having a free end section originating from the end section and the end section connecting to the bundle end.

[0032] In the U-shaped end section, a thickening member is introduced between the ends of the bristles, and all the bristles of the bristle bundle extend around this thickening member.

[0033] The thickened part is located between the bottom and the protrusion and protrudes into the bottom cut-off portion, such that when viewed along the axial direction of the hole, the thickened part has a larger longitudinal dimension than the cross-section of the protrusion, and the thickened part and the bristle bundle are mechanically held in the hole along the axial direction.

[0034] This intermediate product can be transported and handled reliably and easily without the risk of bristle tufts migrating inside the holes. Attached Figure Description

[0035] Other features and advantages of the invention will become apparent from the following description with reference to the accompanying drawings. The drawings show:

[0036] Figure 1 A perspective view is shown of a variant of the hair-implanting device for performing the method according to the invention.

[0037] Figure 2 A schematic cross-sectional view is shown passing through an intermediate product in the form of a bristle carrier according to the invention, which has bristle bundles pushed in before peripheral plastic deformation over time.

[0038] Figure 3 A schematic cross-sectional view of the brush carrier as it is formed through the periphery is shown.

[0039] Figure 4 The diagram shows a longitudinal cross-sectional view through the bristle carrier in the region of two holes, one hole having a plastically deformed periphery and the other hole having a non-plastically deformed periphery.

[0040] Figure 5 A cross-sectional view is shown of the bristle carrier passing through the hole in the region before the bristle bundle is inserted into the region of the thickened part, and...

[0041] Figure 6A longitudinal cross-sectional view through the intermediate product according to the invention is shown. Detailed Implementation

[0042] exist Figure 1 The diagram shows a bristle-planting device that inserts bristle bundles into holes in the bristle carrier 10.

[0043] The bristle carrier 10 can be the entire brush body or only a part of the brush body, such as a small plate.

[0044] The tufting device includes a tool tip 12, a tuft magazine 14, a tuft pickup 16 that can pivot about axis X, and a tack tongue 18.

[0045] The feeder 20 feeds the strip 22 laterally along the direction of arrow A and at a right angle to the filling direction to the tool tip 12.

[0046] The strip 22 is unwound from the roller and fed to the tool tip via the electric drive 24.

[0047] The movement of the tool tip 12 can, for example, be linear along a circular trajectory or other curved trajectory in the direction of arrow B.

[0048] In the illustrated example embodiment, the tool tip 12 is seated on the shaft 26 and can pivot back and forth about the axis D, i.e., from... Figure 1 The tool tip 12 is shown pivoting back and forth from the tamping position at the front dead center to the opposite so-called bundle pickup position, which represents the rear dead center of the tool tip 12. This is to be understood by way of example only and not in a restrictive manner.

[0049] In the illustrated embodiment, which is not to be understood in a limiting manner, the tool tip 12 is seated on the connecting arm 28 of the shaft 26.

[0050] The tamping tongue 18 is hinged at its rear end to the connecting arm 30, which can also pivot about axis D. The cam roller 32 allows control of the connecting arms 28 and 30.

[0051] The movement of the tamping tongue 18 is different from the movement of the tool tip 12; on the contrary, the movement of the tamping tongue 18 is ahead of the movement of the tool tip 12 when moving between the tamping position and the bundle pickup position.

[0052] The tool tip 12 has a front portion 34 that can contact the bristle carrier or move very close to the surface of the bristle carrier. The front portion 34 is fastened at its rear end to a so-called intermediate section 36 and can also be integrally transitioned into the intermediate section 36.

[0053] The front section 34 and the middle section 36 have guide rails 38 inside for filling tongues.

[0054] The feed channel 42 for the strip 22 starts from the top side 40 and extends through the guide rail 38, but terminates at the guide rail.

[0055] Processing unit 46 is used to cut short pieces from the strip, which form so-called thickened pieces 44. These can be seen in the following figures.

[0056] Through the insertion opening 53, the dispersed bristle bundles are inserted into the guide rail 38 between the front portion 34 and the middle section 36, and then stand in front of the strip or pre-cut thickened piece 44, with the front end of the tamping tongue 18 positioned behind the strip or pre-cut thickened piece. The tamping tongue 18 then presses the thickened piece 44 against the bristle bundles and folds the bristle bundles into a U-shape as it pushes them into the guide rail 38.

[0057] Figure 2 A schematic diagram of the hole 48 in the bristle carrier 10 is shown.

[0058] Hole 48 and the remaining holes are blind holes starting from the front side of the bristle carrier 10. Figure 2 As can be seen, the bristle bundle 50 is folded into a U-shape and the U-shape has an end section 52, where the bristle bundle is circumscribed 180°, wherein in the inner end section, i.e. on the inside of the U-shape, the thickener 44 is located in the region of the end section 52. The end section connects the ends of the two bundles having free ends.

[0059] The hole 48 is restricted by the peripheral wall 54 in the bristle carrier 10.

[0060] exist Figure 5 The diagram shows a cross-sectional view through hole 48, which is designed as a circular hole in this case, however this is not absolutely necessary.

[0061] Provide bristles 58 with a diameter f. The holes have an inner diameter D corresponding to their net width.

[0062] The net width W of the thickened part 44 is at most the same as the net width D of the hole, but is especially smaller or minimally larger.

[0063] The net width W of the thickener 44 is preferably selected such that the thickener is not clamped in the hole, or is clamped in the hole slightly laterally, or is slightly cut into the wall 54. The minimum net width W of the thickener 44 in the longitudinal direction (as viewed along the axial direction) must be greater than the diameter D minus the diameter f when the thickener 44 is not clamped in the hole. This eliminates the possibility of a gap forming between the wall 54 and the thickener 44 through which the bristles 58 can be pulled out. Alternatively, the thickener 44 will be elastically pressed / cut into the wall and / or elastically deformed to a minimum.

[0064] For example, the thickener 44 has an oversize of up to 0.2 mm compared to the net width of the hole in the region of the thickener 44.

[0065] In the case of a circular hole 48, the net width of the hole 48 is its diameter. For example, in the case of an elliptical hole, the net width is defined by the distance between opposing hole wall segments 61, which are directly opposite the thickener 44 in the region of their maximum net width. In other words, a narrowest gap is provided between the thickener 44 and the wall 54. The thickener 44 bridges the opposing hole wall segments 61.

[0066] The aforementioned dimensions cause the thickener 44 to keep the wall 54 unchanged during the insertion of the bristle bundle 50, or for the thickener 44 to be pressed into the wall 54 to a minimum, but not cut into, the wall 54. In other words, viewed along the insertion direction of the bristle bundle 50 into the hole 48 (in the illustrated embodiment, the insertion direction corresponds to the axial direction of the hole 48), the thickener 44 has an elongated cross-section. The net width W of the thickener 44 is here at most 0.2 mm larger than the net width D of the hole 48, i.e., in the region of the hole 48 that also receives the thickener 44. Figure 5 In the middle, this area is a vertically extending volume strip that is laterally confined by the outer surface of the thickened member 44 (on the left and right sides) and extends upward to the wall 54.

[0067] exist Figure 6 The diagram shows a longitudinal section passing through the brush carrier 10 in the region of hole 48, so as to describe the geometry of hole 48 in more detail.

[0068] The hole 48 generally has a cylindrical hole wall, wherein a preferably closed and thus annular protrusion 100 is provided at a certain distance from the periphery 60, which minimizes the cross-section of the hole 48 in this region and constitutes a contraction of the hole 48.

[0069] The cylindrical section 102 is located between the periphery 60 and the protrusion 100, and the cylindrical section 106 is located between the protrusion 100 and the bottom 104.

[0070] Optionally, although this is not absolutely necessary, the bottom 104 also has a tapered section 108.

[0071] The cross sections of segments 102 and 106 are preferably identical, such that when viewed axially toward the hole 48, segment 106 forms an undercut due to the protrusion 100.

[0072] The protrusion 100 reduces the cross-section of the hole in the axial region. According to... Figure 6 When viewed in the axial section, the protrusion 100 protrudes inward by only 0.05 mm to 0.2 mm in dimension a relative to the adjacent wall regions, namely the cylindrical sections 102 and 106.

[0073] As from Figure 6 As can be seen, the protrusion 100 extends inward in an arc, continuously and without steps until it reaches its innermost point, and then continuously and without steps again outward to transition into section 106. This also simplifies the manufacturing of the protrusion during injection molding, as an extendable pin with a thickened end is introduced into the mold, which is the negative shape of the hole. After the plastic cures, the pin is then pulled out, making the continuous orientation of the wall in the undercut region important for pulling out the pin. Conversely, the continuous orientation of the wall starting from the periphery facilitates the insertion of the bristle bundle.

[0074] The axial length of the thickener 44 is less than that of the segment 106, and it is used to receive and secure the thickener 44, together with the bristle bundle 50, in the hole 48 in a sufficiently stable manner prior to the plastic forming, which will be explained below. Thus, after the bristle bundle 50 is folded into a U-shape, the arcuate end segment, together with the thickener 44 therein, is pushed into the hole 48, where the thickener 44 elastically deforms outward through the protrusion 100 so as to be held in the undercut, i.e., in the segment 106. Because the thickener 44 has a larger cross-section than the hole 48 in the region of the protrusion 100, the protrusion 100 prevents the bristle bundle 50, together with the thickener 44, from strongly migrating axially within the hole 48 or even exiting the hole 48.

[0075] The bristle bundle 50 can occupy such a volume in the region of the end section that, although the axial length of the thickener 44 is smaller than that of the section 106, the thickener 44 is pre-tightened between the end section and the protrusion 100, i.e., axially clamped in that region.

[0076] However, it is also feasible to adapt the axial dimensions to each other to achieve axial clearance of the thickened part 44 more precisely between the bottom 104 and the end section of the bristle bundle 50 and the protrusion 100.

[0077] Because the thickener 44 is positioned in the undercut, a pull-out force between 5N and 14N is required to pull the bristle bundles 50 out of the holes 48. A maximum pull-out force of 14N per bundle is achieved by the thickener 44 and the protrusion 100 before the periphery 60 is formed. Preferably, the thickener 44 should provide a pull-out force of at least 5N per bundle. In the case of a brush with multiple bristle bundles, the average pull-out force of the bristle bundles is at most 14N and at least 5N, i.e., all bristle bundles are pulled out to determine the pull-out force and the average value.

[0078] This is achieved through the protrusion 100 and the correspondingly sized thickened part 44. Figure 6The intermediate product shown can be stored and handled very easily without the risk of axial displacement of the bristle bundle 50. Even in the case of subsequent forming of the periphery 60, this pre-positioning and retention of the bristle bundle 50 and the thickener 44 is important for the quality of the brush.

[0079] After the bristle bundle 50 is inserted or pushed into the hole 48, pressure is applied to the so-called periphery 60, which is the edge of the hole 48 at the end side 62 in the opening region of the hole 48.

[0080] At this point in time, during the packing process, the bristle carrier 10 is at room temperature, such that the walls 54 and the periphery 60 are not above room temperature and have not yet been heated.

[0081] Compared to the section of the bristle bundle 50 located outside the hole 48, the bristle bundle 50 gains a thickened portion 64 at its end located in the hole 48 through the thickening member 44. The protrusion 100 is also plastically shaped, that is, it transitions to a flange formed by plastic deformation, which produces a contraction portion 68.

[0082] The thickened portion 64 is used to fix the bristle bundle 50 in the hole 48 by plastically shaping the bristle carrier 10 in the region of the periphery 60.

[0083] For this purpose, a forming tool 66 is provided, which may be a separate tool or may be formed from the tool tip 12 of a filling tool.

[0084] The forming tool 66 can, for example, deform the periphery 60 and the material beneath it by a single impact, causing this material of the bristle carrier 10 to plastically yield inward, so that the hole 48 narrows in its opening region, i.e., narrows at least 70% of the cross-section of the thickened member 44, preferably at least 90% of the cross-section of the thickened member 44, more preferably at least the cross-section of the thickened member 44. The contraction portion 68, i.e., the flange, in... Figure 3 Reference numeral 68 is provided in the figure. The constriction 68 provides an undercut that is even more pronounced than the protrusion 100, wherein the thickened portion 64 may be located in the protrusion, but the bristle bundle 50 can no longer be pulled out from the undercut due to the thickened portion 44. Mechanical obstruction occurs.

[0085] During this forming process, the bristle bundles 50 may optionally be radially compressed in the region between the thickened part 44 and the periphery 60.

[0086] Preferably, the forming tool 66 is used to perform plastic deformation with or without heating the periphery 60. If the periphery 60 is to be heated, the forming tool 66 can be heated at least in the region of its end side 70. In this case, the periphery 60 can be at room temperature before contacting the forming tool 66.

[0087] However, alternatively and preferably, this heating is not provided, and the impact pulse is sufficient to cause plastic deformation of the brush carrier in the periphery 60 region.

[0088] An alternative to this single-impact pulse is a forming tool 66 in the form of an ultrasonic oscillator 72, wherein the end side 70 is slightly pressed against the periphery 60 and vibrates thereon on multiple axes or directions, thereby heating the plastic material beneath the end side 70.

[0089] It is generally advantageous that the hole 48 remains undeformed in the region of the bottom 104, preferably in the entire region where the end section is located.

[0090] As already mentioned, the bristle carrier 10 is preferably made of plastic.

[0091] The thickened part 44 is not made of metal, but of a different material, especially plastic, and more precisely, preferably even of the same plastic as the wall 54 and / or the bristles.

[0092] For this alternative, the thickened part 44 can be made of paper or cardboard, and the enumeration is not exhaustive.

[0093] Figure 4 Two thickened parts 44 are shown, whose cross-sections are rectangular when viewed at a right angle to the axial direction of the hole 48, making the shape of the thickened parts 44 cubic.

[0094] Alternatively, the thickener 44 may also have a wedge shape, having a thin or narrow end pointing towards the bottom of the hole 48. The thickener 44 has a length L in the axial direction, which corresponds at most 50% of the maximum depth T of the hole 48.

[0095] exist Figure 4 In the middle, the upper hole 48 has undergone plastic deformation and shrinkage in the area of ​​the periphery 60, but the lower hole 48 has not yet undergone plastic deformation and shrinkage.

[0096] Typically, the wall 54 of the un-plastic-deformed hole, more specifically, the portion of the wall forming the periphery, should initially be constructed as cylindrical. This facilitates the insertion of the unit consisting of the bristle bundle 50 and the thickener 44.

[0097] Figure 1 The hair implantation equipment shown also includes Figure 3 The forming tool 66 shown has a punch or ultrasonic oscillator 72, and the processing unit 46 also includes a tool 80 for separating the thickened part 44 from the strip 22.

[0098] In the illustrated embodiment, the tool 80 is a cutting blade that is moved by a reciprocating drive.

Claims

1. A method of manufacturing a brush, the brush comprising a bristle carrier (10) having at least one pre-formed hole (48) and a bristle bundle (50) for each hole (48), wherein the hole or each hole (48) has a laterally defined hole (48) and an inner wall (54) and a periphery (60) surrounding the hole (48) at a front side of the bristle carrier (10), the method characterized by the following steps: - A bristle carrier (10) is provided in which the wall of one or more holes (48) to be filled has at least one protrusion (100) at a distance from the bottom (104) of the disposed hole (48) to reduce the cross-sectional area of ​​the hole, the protrusion reducing the cross-sectional area of ​​the hole along the axial section, such that an undercut is formed between the protrusion (100) and the bottom (104). - The bristle bundle (50) is folded into a U-shape, the bristle bundle having an arc-shaped end section, a bundle end with a free end starting from the end section and the end section connecting the bundle ends, wherein a thickening member (44) is introduced in the U-shaped end section between the bundle ends, and all the bristles of the disposed bristle bundle (50) extend around the thickening member. - The bristle bundle (50) and its thickener (44) are pushed so deeply into the hole (48) that the thickener (44) is positioned between the bottom (104) and the protrusion (100), wherein the protrusion (100) prevents the thickener (44) from being pulled out, and - The periphery (60) is then plastically shaped under pressure, such that the cross-section of the hole (48) at the periphery is reduced to at least 70% of its initial cross-section, and the hole (48) thus obtains a flange in the area between the front side and the thickener (44), and the thickener (44) is located in an undercut formed between the flange and the bottom (104), wherein the flange mechanically blocks the thickener (44) and the bristle bundle (50) to prevent them from being pulled out.

2. The method according to claim 1, characterized in that, During the plastic forming process, the protrusion (100) is also formed and becomes part of the flange.

3. The method according to claim 1 or 2, wherein the cross section of the thickened member (44) is adapted to the cross section of the hole (48) in the region of the protrusion (100) and between the protrusion (100) and the bottom (104) to provide a pull-out force between 5 N and 14 N prior to the plastic forming.

4. The method according to any one of the preceding claims, characterized in that, Prior to the plastic forming, the thickened part (44) is abutted against the wall (54) and / or axially received in the hole (48) with a clearance between the bottom (104) and the protrusion (100), or axially sandwiched between the bristle bundle (50) and the protrusion (100) in the region of the end section.

5. The method according to any one of the preceding claims, characterized in that, The protrusion (100) is a closed, surrounding contraction.

6. The method according to any one of the preceding claims, characterized in that, The periphery (60) is formed such that the resulting flange is kept at a distance from the bottom (104) relative to the axial length of the thickening member (44), such that the thickening member (44) is received in the axial direction without tension between the bottom (104) and the flange.

7. The method according to any one of the preceding claims, characterized in that, Plastic deformation also occurs when the periphery (60) is heated, especially when a heated punch is used, which also receives at least one of the bristle bundles (50), or plastic deformation is performed by an ultrasonic oscillator placed on the periphery (60) and heating the bristle carrier (10) in that area and applying pressure, or by using a punch that deforms the periphery (60) by means of a single impact.

8. The method according to any one of the preceding claims, characterized in that, The bristle carrier (10) is made of plastic, and the thickening member (44) is made of plastic, especially the same plastic as the bristle carrier (10), or paper or cardboard.

9. The method according to any one of the preceding claims, characterized in that, The protrusion (100) protrudes inward by 0.05 mm to 0.2 mm relative to the adjacent wall region.

10. The method according to any one of the preceding claims, characterized in that, The protrusion (100) extends continuously and without steps inward from the direction of the periphery (60) to the innermost point of the protrusion, and then extends continuously and without steps outward again and transitions into the rest of the wall.

11. The method according to any one of the preceding claims, characterized in that, A thickened part (44) is used, the axial length of which is at most half the maximum depth (T) of the provided, non-plastically deformed hole (48).

12. The method according to any one of the preceding claims, characterized in that, The hole (48) remains undeformed in the region of the bottom (104) during the plastic forming of the periphery (60).

13. The method according to any one of the preceding claims, characterized in that, The bristle carrier (10) is at room temperature when at least one of the bristle bundles (50) is pushed in.

14. The method according to any one of the preceding claims, characterized in that, Between the protrusion (100) and the bottom (104) and / or between the protrusion (100) and the periphery (60), the wall (54) of the hole (48) is cylindrically formed, especially except for the protrusion (100), the wall (54) of the hole (48) is cylindrically formed.

15. An intermediate product for carrying out the method according to any one of the preceding claims, the intermediate product comprising: - A bristle carrier (10) having at least one pre-formed hole (48) having a wall (54) laterally defining the hole (48) and having an inner wall and a periphery (60) surrounding the hole (48) at the front side of the bristle carrier (10), wherein the wall (54) of one or more holes (48) to be filled has at least one protrusion (100) at a distance from the bottom (102) of the disposed hole (48) to reduce the cross-sectional area of ​​the hole, the protrusion (100) reducing the cross-sectional area of ​​the hole along the axial section, such that an undercut is formed between the protrusion (100) and the bottom (102). - A U-shaped folded bristle bundle or, in the case of multiple holes (48), a U-shaped folded bristle bundle (50) located in each hole (48), the bristle bundle (50) having an arc-shaped end segment, a bundle end with a free end starting from the end segment and the end segment connecting to the bundle end. - In the U-shaped end section, a thickening member (44) is introduced between the ends of the bundle, and all the bristles of the disposed bristle bundle (50) extend around the thickening member, and - The thickening member (44) is located between the bottom (104) and the protrusion (100) and protrudes into the undercut, such that when viewed along the axial direction of the hole (48), the thickening member (44) has a larger longitudinal dimension than the cross-section of the protrusion (100), and the thickening member (44) and the bristle bundle (50) are mechanically held in the hole (48) along the axial direction.

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