EP0289489B1 - Process for the manufacture of bristled articles and bristled articles produced by said process - Google Patents

Abstract

Bristled articles having a bristle mounting (1) with at least one hole (2) on each of its opposing faces for the insertion of single or bundles of artificial bristles (3) in order to furnish the opposing faces with bristles are produced in such a way that the holes in the bristle mounting (1) connect. The bristles (3) inserted from both sides of the bristle mounting (1) are melted at the end which faces the bristle mounting (1) and are inserted into the opposing holes until the melted substances have come in contact.

Description

The invention relates to a method for producing bristle goods with a bristle carrier which has at least one hole on each side for receiving individual or bundled plastic bristles to form bristle trimmings on the opposite sides, and bristle goods produced by this method.

Typical examples of bristle goods of the aforementioned type are hand washing brushes or toothbrushes covered on both sides, belts, bands or disks covered with bristles for technical purposes, in particular for brushing machines or mats provided with bristles on both sides, e.g. B. Door mats. Such bristle products have hitherto been produced in such a way that, in the case of rigid bristle carriers, blind holes are introduced on both sides - usually with a mutual offset - and the bristles are introduced into these holes, which are then anchored in the holes. With thin, flexible bristle carriers, however, a perforated or fabric-like structure is used and bristles are threaded through the open structure and mechanically attached to the bristle carrier. The processes are complex in terms of production technology and are expensive.

Due to the increasing use of plastic bristles and bristle carriers made of plastics, efforts have been made for many years to connect bristle carriers and bristles to one another by welding with bristle articles covered with bristles on one side. The ends are pressed bluntly onto the melted surface of the bristle carrier. After the melt solidifies, the connection is established.

With butt welding there are problems in the choice of plastics. To a degree that is satisfactory for long-term use, it is essentially only possible with the same bristle and bristle carrier materials. Since the bristles have to consist of relatively high-quality plastics because of their stress, this requires the use of equally high-quality plastics for the bristle carrier, which would not be necessary per se for purely technical reasons. This makes the product unnecessarily expensive.

Unequal material pairings can be used if the bristles are inserted into blind holes and they have undercuts, behind which the melt can flow, in order to achieve perfect anchoring. The production of such undercuts in blind holes is only possible with complex tools.

It is also known that, in order to produce an annular or cylindrical bristle product, the open, planar structure is shaped into a ring with its edges overlapping them, and the melted end of bristle bundles is pushed through the overlapping region. After solidification, not only are the bristles anchored, but the ring is also closed at the same time.

The aforementioned prior art is comprehensively described in DE-OS-2 335 468, which is why this publication can be regarded as exemplary for the entire area of the welded or fused connection of bristles and bristle carriers.

The invention has for its object to provide a method for producing bristle products with bristle trimmings on both sides or bristle products of this type, which allows simple and inexpensive production, safe anchoring of the bristles in the bristle carrier with any selection of the material for the bristle carrier.

This object is achieved in that the holes on the opposite sides are introduced into the bristle holder in such a way that they are connected to one another in such a way that the bristles fed to the bristle holder from both sides melted at their ends facing the bristle holder and into the opposite holes to collide the melted ends within the holes and press against the hole wall.

In departure from the previous technology, in which the bristles or bundles of bristles are each connected only to the bristle carrier, the invention goes the way, the bristles on one side of the bristle carrier directly collide with the bristles on the other side, whereby the melted ends connect with weldable plastics or press against the perforated wall with non-weldable plastics and this creates a frictional connection. It is readily apparent that when using the method according to the invention, the bristle carrier, which does not need to participate in the fusible link itself, can, however, participate if necessary, from any material, e.g. B. plastic, wood, metal or the like, without this could adversely affect the connection of the bristles with each other and with the bristle carrier.

In a preferred embodiment of the method it is provided that projections and / or undercuts and / or roughness for anchoring the bristles in the melted area are attached to the bristle carrier in the area of the holes, for. B. on the occasion of its production or subsequently generated by hot molding. The provision of projections, undercuts or even only roughness on the through holes of the bristle carrier improve the anchoring of the bristles, these measures being effective against pull-out forces in both directions. The production engineering of such undercuts or protrusions is both in mechanical or thermal manufacture of the holes, as well as in the manufacture of the bristle carrier and the holes by casting, for. B. Injection molding, possible without difficulty, since each projection protruding into the clear width of the holes forms an undercut on both sides of the opposite bristles, so that in fact only projections or roughness are necessary in order to achieve an improved pull-out-resistant anchoring. In the case of thin bristle carriers and / or deep melting of the bristle ends, the melt remains on the outside of the bristle carrier, forming a supporting bead.

A bristle product manufactured according to the aforementioned method with a bristle carrier and plastic bristles arranged on opposite sides in holes in the bristle carrier is characterized in accordance with the invention in that the holes arranged on opposite sides are connected to one another and those from opposite sides are at least up to Bristles introduced into each other are connected to one another by fusing in the contact area. It is preferably provided that the bristle carrier has projections and / or undercuts and / or roughness in the region of its holes for anchoring the bristles.

In a preferred embodiment, the bristle carrier has through-holes and projections projecting inwards therein, the projections being able to be designed as individual or ring-shaped closed lugs, as transverse webs or as a constriction of the through-hole.

A modified embodiment is characterized in that the merging holes are arranged on the opposite sides of the bristle carrier so that they are offset from one another in the transition area. In this embodiment, the offset of one hole from the other creates an undercut for the bristles on the opposite side in each case. Staggered holes, if they overlap in depth, can lead to the formation of feet in the case of non-weldable bristle material.

According to a further exemplary embodiment, the bristle carrier has an annular elevation projecting beyond its surface at the opening edge of the holes. This ring-shaped elevation surrounds the melt which is displaced when the molten bristle ends are introduced. This measure also makes it possible to make the bristle carrier extremely thin-walled, possibly flexible, and at the same time to obtain a sufficiently large depth of the holes for the attachment and guiding (lateral support) of the bristles.

If the annular elevation on the inside has a run-in slope for the insertion of the bristle bundles, there is the further advantage in terms of production technology that the melting bead formed when the bristle ends are melted can be introduced more easily into the hole. This can be further supported by the fact that the holes in the bristle carrier have inward inclines running from their opening edge.

In bristle products produced according to the invention, not only can bristles and bristle carriers consist of different materials, but also the bristles themselves can consist of different plastics, since they are sufficient in the melting area by pressing them against the perforated wall and / or in connection with the projections or roughness at the through holes Receive anchoring even if the two materials do not weld together. Of course, bristles made of different materials in different configurations and densities can also be arranged in regions on a single bristle carrier.

• - Fig. 1 eine schematische Darstellung einer Ausführungsform des Verfahrens in einer Verfahrensstufe;
• - Fig. 2 einen Schnitt einer Ausführungsform einer Bürste;
• - Fig. 3 - 9 je einen vergrößerten Teilschnitt verschiedener Ausführungsformen der Verbindung der Borstenbündel untereinander und/oder mit dem Borstenträger;
• - Fig. 10 - 11 eine Detail-Draufsicht auf einem Borstenträger mit verschiedenen Ausführungsformen für die Verankerung der Borstenbündel;
• - Fig. 12 - 13 je einen Detailschnitt eines Borstenträgers mit weiteren Ausführungsformen für die Verankerung der Borstenbündel.

Further details and advantages of the invention result from the following description of some embodiments shown in the drawing. The drawing shows:

• - Fig. 1 is a schematic representation of an embodiment of the method in a process step;
• 2 shows a section of an embodiment of a brush;
• 3 to 9 each show an enlarged partial section of different embodiments of the connection of the bristle bundles to one another and / or to the bristle carrier;
• 10-11 show a detailed top view of a bristle carrier with different embodiments for anchoring the bristle bundles;
• 12 to 13 each show a detail section of a bristle holder with further embodiments for anchoring the bristle bundles.

In Figure 1, a bristle carrier (1) can be seen in longitudinal section, as is known for example for hand washing brushes with bristle trimmings on both sides. In a departure from the known designs, the bristle carrier (1), which can be made of any material, has through holes or bores (2) which are produced during its manufacture (injection molding, foaming or the like) or afterwards by drilling, thermoforming or the like can. A bristle bundle (3) is inserted from each side into each through hole (2) of the bristle carrier (1) and is melted at its end (4) beforehand. The bristle bundles (3) preferably sit in a common holder for each side of the bristle carrier (1), so that they can be inserted into the through holes (2) at the same time. The ends (4) of the bristle bundles (3) can be melted by contact heat or by contactless heating. In Figure 1, the so-called heating mirror method is shown as an example, in which between the clamped Bristle holder (1) and the bristle bundles (3) sitting in the holders, not shown, a heating mirror (5) is retracted until the ends (4) are sufficiently softened. The heating mirrors (5) are then moved outwards in accordance with the double arrow shown and the bristle bundles (3) are inserted into the through holes (2).

As can be seen from FIG. 2, the bristle bundles (3) are introduced until they collide at the melted ends and the melt spreads out in the through hole. The type of anchoring of the bristle bundles in the bristle carrier (1) can be carried out in various ways, as described below using several embodiments.

In the embodiment according to FIG. 1, the through hole (2) in the bristle carrier (1) is designed as a continuous cylindrical bore, possibly provided with a certain surface roughness. The bristle bundles (3) inserted into the through hole (2) from opposite sides and melted at their leading ends form a thickening (6) at the joint. This thickening (6) lies non-positively on the wall of the through hole (2), so that the bristle bundles (3) are anchored here.

FIG. 4 shows an embodiment in which an improved anchoring is achieved in that the through-hole (2) has nose-like projections (7) at approximately the middle height, which can optionally also be combined into a single annular projection. This results in a narrowing in the central area of the through hole (2). The confluent melt (8) of both bristle bundles (3) also flows behind the projections (7), so that the bristle bundles (3) are secured against pull-out forces in both directions.

While in the embodiments according to FIGS. 3 and 4 the bristle bundles (3) preferably consist of the same material that can be welded to one another, FIG. 5 shows an embodiment that is also suitable for non-weldable material. Here projections (9) are provided in the through hole (2) in the central area, but at different heights. Due to the offset of the projections (9), the melt (10) of each bundle of bristles can flow behind one or a part of these projections (9), so that each bundle of bristles (3) is anchored in the bristle holder. As shown, for example, in FIG. 11, a plurality of such nose-like projections (9) can be arranged on the inner circumference of the through hole (2).

Figure 6 shows a bristle carrier (1) in the form of a tube (11), in which the bristle bundles (3) are non-positively fixed again after their melted ends converge, forming a thickening (6).

FIG. 7 shows a similar embodiment with a very thin bristle carrier (1) with sleeve-like guides (12) protruding on both sides, which in turn form a through hole (2) in which the bristle bundles (3) are anchored in a force-locking manner with a thickening (6) .

FIG. 8 shows an embodiment in which the bristle carrier (1) 2 has holes (2) made or produced from opposite sides, the axes of which are offset from one another, so that an undercut (13) is created in each case. When the melted ends of the bristles (3) come into contact, the melt flows behind the undercuts (13), forming a thickening (14), so that each bundle of bristles is anchored in a form-fitting manner. This embodiment is also suitable for bristle material that cannot be welded to one another.

In the embodiment according to FIG. 9, a very thin-walled bristle carrier (1) is again provided, which can optionally also be designed to be flexible and flexible. The bristle bundles (3) are melted at their ends so far that when the bristle bundles (3) are inserted into the through hole (2) and when they collide, a small amount of melt is accumulated on the outer sides 15 of the bristle carrier (1), which after gives a bead (16) on cooling. Because the melt flows together in the central region (17), the bristle bundles (3) are again secured against pull-out forces in both directions.

Figure 10 shows only a detailed view of a bristle carrier (1) with a through hole (2), within which a transverse web (18) is arranged, which ensures the necessary anchoring of the bristle bundles if necessary.

In the exemplary embodiment according to FIG. 12, the through hole (2) is produced by two mutually offset holes, the bottom (19) of which in each case forms an undercut for the bundle of bristles inserted from the opposite side. In contrast to Figure 8, the two holes are not offset in depth. This embodiment is therefore preferably suitable for bristle material that can be welded together.

Finally, an exemplary embodiment is shown in FIG. 13, in which the through hole (2) has conical walls (20) which form a kind of run-in slope for the melt of the bristle bundles. Possibly. the inlet slope can also be extended to a bead (21) projecting beyond the outside of the bristle carrier (1).

The description of the aforementioned embodiment shows that any plastic can be used for the bristles and that - with appropriate mechanical anchoring means - different plastics can be used for the two sides of the bristle carrier, for example to achieve different bristle hardness on both sides. It is also possible to have bristle bundles of different diameters or cross-sections or with under on both sides of the bristle carrier use different bristle number and / or bristle color. Furthermore, the bristle carrier can consist of any material. In addition, almost any thin bristle carrier can be used, since a very small height is sufficient for the force-fitting or form-fitting anchoring, in particular band brushes or the like can also be produced in this way for industrial purposes. Only a few possibilities that the invention offers are shown above.

Claims (13)

1. Process for the production of bristle articles with a bristle carrier having on opposite sides in each case at least one hole for receiving individual or bundlewise-combined plastic bristles for providing a bristle coverage on the opposite sides, characterized in that on the opposite sides, the holes are made in the bristle carrier in such a way that they are interconnected, that the bristles supplied from the two sides to the bristle carrier are melted at their ends facing the bristle carrier and are inserted into the facing holes until abutment occurs of the melted ends within the holes and then are pressed against the wall of the hole.

2. Process according to claim 1, characterized in that projections and/or undercuts and/or roughnesses are provided in the vicinity of the holes on the bristle carrier for anchoring the bristles in the melted area.

3. Process according to claims 1 or 2, characterized in that the projections and/or undercuts in the vicinity of the holes of the bristle carrier are produced during the manufacture thereof.

4. Process according to one of the claims 1 to 3, characterized in that the ends of the bristles are melted to such an extent that after they have been inserted in the holes of the bristle carrier, the melt is left on the outside of the bristle carrier, accompanied by the formation of a bead.

5. Bristle article, produced according to one of the claims 1 to 4, comprising a bristle carrier and plastic bristles arranged on opposite sides in holes of the bristle carrier, characterized in that the holes on opposite sides are connected and the bristles inserted from the opposite sides into the holes at least until they come into contact with one another are interconnected in the contact area by fusion.

6. Bristle article according to claim 5, characterized in that in the vicinity of its holes, the bristle carrier has projections and/or undercuts and/or roughnesses for anchoring the bristles.

7. Bristle article according to claims 5 or 6, characterized in that in the vicinity of the outsides of the bristle carrier, the bristles have on the edge of the holes in the molted state shaped-on beads.

8. Bristle article according to one of the claims 5 to 7, characterized in that the bristle carrier has through-holes and in the same inwardly projecting projections.

9. Bristle article according to claim 8, characterized in that the projections are constructed as individual or annularly closed noses, crossbars or constrictions of the through-hole.

10. Bristle article according to one of the claims 5 to 9, characterized in that the holes passing into one another are so arranged on the opposite sides of the bristle carrier, that they are recip- rocately displaced in the transition area.

11. Bristle article according to one of the claims 5 to 10, characterized in that on the opening edge of the holes, the bristle carrier has an annular protuberance projecting over its surface.

12. Bristle article according to claim 11, characterized in that on the inside, the annular protuberance has a feed slope for inserting the bristle bundle.

13. Bristle article according to one of the claims 5 to 12, characterized in that the holes in the bristle carrier have feed slopes passing from their opening edge to the inside.

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