BE1017010A3 - METHOD AND DEVICE FOR MANUFACTURING BRUSHES AND BRUSHES SO MANUFACTURED - Google Patents

Abstract

A round brush, in particular a twisted interdental brush, has a brush blank (10) composed of a wire-twisted carrier part (5) with a bristle lining (6) on the side of the head. A handle (3) is attached to the hair-free end (7) of the carrier part. The end section (8,8a, 8b) of the hairless end (7) of the carrier part, which is located in the handle (3), is deformed, for example in an L-shape and kept locked by a form connection. inside the handle (3). The handle (3) is preferably designed in two parts, the deformed end (7) of the carrying part being inserted inside a part (9) of the handle and being secured against extraction and unscrewing by the handle. 'other (16) of the handle. (figure 1).

Description

The invention relates to a method for the manufacture of brushes which have a brush blank consisting of a twisted wire carrying portion with a pile lining on the side of the brush. head and a handle. The invention further relates to a device for the manufacture of brushes and brushes thus manufactured.

Such twisted brushes are used, for example, as interdental brushes or cosmetic brushes. During manufacture, the bristles are first inserted into the twisted wire and this brush blank with bristles on the side of the head is then connected to a handle, in that the ends of the bristle-free ends of the carrier part are heated and then inserted into a hole of a handle made of synthetic material. The handle can also be connected to the brush blank by inserting the end of the carrier part by injection.

The ends of the twisted carrier part engaging in the handle form a net, so that there is in general sufficient strength of connection opposing the extraction of the carrier portion of the handle. However, the carrier portion can be unscrewed when the small brush is inclined to the side and then has a corresponding lever arm for unscrewing.

Moreover, in the case of interdental brushes, the area of the bristles of the brush can be wedged in a space between the teeth and the brush handle can, when attempting to release the brush, be unscrewed or removed from the carrying portion . The sharp ends of wires in the open air can cause injuries in the oral cavity. There is also a risk that the sleeveless brush may be swallowed.

The aim is therefore to provide a method and a device of the type mentioned at the beginning and a brush thus manufactured, the maintenance of the twisted carrier part in the handle of the brush being improved and an unwanted release of the handle of the carrying part. being avoided.

The solution to this problem consists, as far as the method is concerned, in that the bristle blank with bristles on the side of the head is connected to a first part of the handle of the brush leaving free a terminal section of the head. hair-free end of the carrier and in that the terminal section left free is deformed and enclosed by the second portion of the handle of the brush.

With regard to the device, it is proposed that it has a deformation device for deforming an end section of the hair-free end of the carrier portion passing through a first portion of the brush handle and a device for connecting the first portion of the handle of the brush to the second portion of the handle of the brush and to enclose the deformed end section of the carrier portion free of hair and ensure its position.

It is thus possible to manufacture a brush whose handle is designed in two parts, the deformed end of the carrier part being placed inside one of the parts of the handle and being protected by shape connection by the other party handle against unscrewing and extraction. Even under unfavorable conditions, an unwanted separation of the handle from the rest of the brush is practically no longer possible because of this protection.

A development of the manufacture may consist in that, in a first step, the first part of the handle of the brush comprising a reception opening for inserting the hair-free end of the carrying part is injection molded, in that subsequently the end of the hair-free carrier portion is introduced into and through the receiving aperture and a free end section protruding from the end of the carrier portion is deformed and the second portion of the handle of the brush surrounding the Deformed end section is then preferably injection molded.

In this way, a basic body of the brush handle can initially be made by injection molding and then be connected to the brush blank, and thus to the carrier portion with bristles. These connected parts are then placed in an injection mold where the second portion of the handle of the brush is injection molded as a second component and thereby encloses the deformed end section of the carrier part.

According to another proposal, the brush blank may be inserted by injection into the first portion of the brush handle leaving free an end section of the hair-free end of its carrier part, and the free terminal section protruding from the end of the carrier portion is deformed and then the second portion of the brush handle surrounding the deformed end section is preferably injection molded.

In this case, the connection of the base body of the brush handle with the bristled carrier portion has already taken place during the injection molding of the brush handle, so that a separate mounting operation is eliminated.

In this way, a brush, whose two-part handle consists of injection molded parts, can be manufactured by two-component injection molding with a deformation operation provided for the end section of the carrier part between the molding operations. by injection, the deformed end section of the carrier part being embedded by injection within one of the parts of the handle and thus ensured by shape connection against extraction and unscrewing.

The brush blank is generally constituted by a symmetrical straight part which, after its manufacture where the bristles are inserted into the turned thread, is easily handled and can therefore be conveyed automatically to the machine. other finishing operations. The routing of the ends of hair-free yarn to a part of handle pre-molded by injection and the insertion into its receiving opening can in particular be done without problem. As well as the routing and placement in an injection mold.

According to an independent proposal of the invention, it is provided that the brush blank is deformed at the end section of the hair-free end of its carrier part and is then placed in an injection mold and then at least a portion of the handle or handle is injection molded and, in doing so, that the end of the carrier portion is recessed by injection at least at its deformed end section.

This method can be used particularly advantageously when the deformation of the end section of the hair-free end of the carrier part is symmetrical of revolution, so that the position in which the brush blank is conveyed is random in that which concerns the direction of rotation about the longitudinal axis. Even in the case of asymmetrical deformation, for example unilateral deformation, it is possible to use this manufacturing method when there are in the mold by injection arrangements to fix the position in a predefined position or place desired. It should also be taken into account in this case that the size of the deformation is smaller than the cross section of the section of the handle in this region surrounding the deformation.

When the brushed brush blank on the head side is inserted with its hair-free end region into a passage of an injection mold portion and is injection-molded to form a brush handle, it is advantageous that the section of the opening of the passage of the mold part is modifiable and is reduced for a tight and essentially tight hold of the hair-free end and inserted into the carrier part of the brush blank and the section of the opening of the portion of the mold portion is enlarged after injection molding of the brush handle for removal of the brush.

By reducing the section of the opening of the passage of the mold part, the tolerances of the section of the wires of the twisted wire carrier part are compensated, so that even if the wire section is undersized, the sections of yarn are firmly held and, if necessary, compressed or deformed by clamping so that the passage of the mold part is sealed during injection molding of the handle of the brush or a part thereof. this. Therefore, it is possible to work with a high injection pressure which also contributes to a better maintenance of the thread turned in the plastic handle. In addition, an exit of the synthetic material through the passage of the mold part is avoided with certainty.

In order also to avoid, during the injection molding of the second injection-molded component, and thus of the injection-molded part which surrounds the deformed end section of the hair-free end of the carrier part, that the injected material advances in the receiving opening and through it into the pile lining, it is provided in accordance with a particularly advantageous improvement of the invention that, during manufacture, in particular the injection molding of the first part of the sleeve of the brush, an annular bead is formed thereon in the extension of the receiving aperture for receiving the hair-free end of the carrier portion which is opposed to the bristle pad, annular bead which, during molding by injection of the second portion of the brush handle and due to the external pressure exerted on the annular bead by the injection molding, It is deformed into a sealing collar and is pressed tightly around the end of the carrier part.

The length and wall thickness of the annular bead can be sized in accordance with the material of the annular bead, the injection pressure and the required deformation. The sealing effect to be achieved can thus be influenced by the material and the dimensions of the annular bead.

A brush made according to a process according to the invention by means of a device according to the invention, in particular a twisted interdental brush, is characterized in accordance with the invention in that the end section of the hair-free end of the carrier part, which is in the handle, is deformed and is kept locked by shape connection inside the handle.

As already mentioned above, the brush with the carrier part is ensured in this case by form connection against an extraction and unscrewing of the handle part, this is also valid under unfavorable conditions.

The two-part handle may be preferably injection molded parts, the deformed end of the carrier portion being embedded by injection within one of the handle portions.

According to one embodiment, the round brush may be disposed with its head-side hair pad and the barely aligned handle. According to another embodiment, however, the round brush may also be disposed with its head-side hair lining and the handle at an angle to each other so that in the case of a small tooth interdental brush, the spaces between the back teeth can be better achieved.

The round brush may have an at least two-part handle, composed of at least two injection-molded components, a base body of the handle with a receiving opening for the hair-free end of the carrier portion having the an annular bead protruding into another injection-molded part, an annular bead to which the deformation of the end section of the hair-free end of the carrier portion which is surrounded by the other injection-molded part is connected.

The annular bead can in this case form a support in the axial direction for the deformed end section, so that there is then also a substantially immovable fastening in the longitudinal direction, when comparatively soft material is used as a second molded component by injection.

Other designs of the invention result from the other claims. The invention is explained below on the basis of the various embodiments as well as the following description of the figures.

FIG. 1 shows a longitudinal sectional representation of an embodiment of an interdental brush with an end section, once folded L-shaped, of the hair-free end of its carrier part,

FIG. 2 shows a longitudinal sectional representation of an interdental brush with a hook-shaped end section of the hair-free end of its carrier part;

FIG. 3 shows a longitudinal sectional representation of an interdental brush with a folded handle,

FIG. 4 shows a longitudinal sectional representation of an interdental brush which has not yet been completed during the injection molding of another component of injection molding material,

FIGS. 5 to 11 show a series of finishing steps, represented diagrammatically, in the manufacture of round brushes according to the invention,

Figures 12 to 15 show finishing steps corresponding approximately to Figures 8 to 11, but here with other auxiliary tools,

FIGS. 16 to 19 show a representation of finishing steps corresponding approximately to FIGS. 8 to 11, but here with finishing tools for the formation of hook-shaped deformations,

Figures 20 to 23 show a sequence of finishing steps in the manufacture of folded round brushes,

Fig. 24 shows an injection molding device with a carousel serving as a transport device and simple molds for injection molding of handle components,

Fig. 25 shows a device corresponding approximately to Fig. 24, but here with multiple molds, and

Figure 26 shows a three station multiple mold for round brushes with folded handle.

A round brush 1, 1a shown in Figures 1 and 2 consists essentially of a brush portion 2 and a handle 3. The brush portion 2 has a carrier portion 5 twisted wire 4 which carries at its outer end a seal of bristles 6 and which is connected to the handle by means of the end 7 without bristles of its carrier part. To securely anchor the carrier part 5 in the handle 3, an end section 8 of the hair-free end 7 of the carrier part, which is inside the handle, is deformed and kept locked by shape connection in the handle. In FIG. 1, it can be seen that the L-shaped end section is thus folded once, while the round brush 1 according to FIG. 2 has a hook-shaped multiple fold of its end section 8. It is guaranteed thanks to these deformations that the brush part 2 can not be unscrewed from the handle 3.

Figure 3 shows a round brush 1b in which the brush portion 2 and the handle 3 are disposed at an angle relative to each other. Here again, it can be seen that the hairless end 7 of the carrying part, which is inside the handle 3, has an end section 8 folded several times, so that there is also here an anchorage sure in the handle 3.

The handle 3 is preferably designed as an injection molded part, a handle 3 composed of two injection molded components being provided in the embodiment. The injection molded components may be in the same material or in different materials.

Figures 5 to 11 show the different finishing steps in the manufacture of a round brush 1 right. Figure 5 shows a base body 9 of the handle which has been manufactured by injection molding. Figures 6 and 7 show how a brush blank 10 consisting of the carrier part 5 and the head-side hair pad 6 is inserted into a receiving opening 11 of the base body 9. The end 7 free of In this case, the bristles of the carrier portion are pushed into the receiving opening 11 preferably until the brush portion 2 is adjacent to the base body 9 (FIG. 8). After this finishing step, the inner end of the hairless end 7 of the carrier part protrudes with its end section 8 from the inner end of the receiving opening 11. To deform the end section 8 into L, a deflection slide 12 is provided, one end side of which engages laterally with the end section 8 in front of it in the interior, and the end region 8 is folded (FIG. 9) by the displacement of the deflection slide 12 according to the arrow Pf 1 in FIG 8. The terminal section 8 deformed is only of a length such that it rests inside the section of the handle or the recess 14.

Depending on the required deformation force and the inherent stability of the base body 9, it may be necessary to press the part of the carrier part which follows the end section 8 on the side opposite to the deflection slide 12. This is done in the embodiment with a counter-stop 13.

The base body 9 of the handle, which has a recess 14 on the inner side, has in the extension of the receiving opening 11 an annular bead 15 whose inner end forms the outlet opening of the recess 14. The against-abutment 13 comes into engagement externally, during the folding of the end section 8, with this annular bead 15 (FIGS. 7 to 9). In FIG. 10, the tools -folding roll 12 and counter-stop 13-are withdrawn laterally from the recess 14 of the base body 9 and the brush blank 10 is provided by the end region 8 folded against an extraction. The injection molding of the second portion 16 of the handle which then fills the recess 14 as part of the handle 3 (Figure 11) takes place in a next step.

The folded end section 8 is then surrounded by this second handle part so that a rotation of the carrier part 5 is no longer possible. In the exemplary embodiment, the portion 16 of the handle formed by a second injection molding is closed on the outer side in alignment with the base body 9. However, it is also possible to embed the base body by injection on the side. at least partially outside. For example, this can be done with a somewhat softer component, rubbery type, which gives better handling.

The annular bead 15 serves on the one hand to support the carrier part 5 in wire during folding or deformation of its end section 8. In addition to being used for placement against the abutment 13. On the other hand, annular bead 15 also has a sealing function that avoids penetration of liquid material for injection molding in the receiving opening 11 during the injection molding of the second part 16 of the handle and, where appropriate, the through which it passes into the region of the pile lining 6. In FIG. 4, a dashed line indicates a mold part 17 surrounding the handle 3 which also delimits the recess 14 so that the outer contour desired is formed during injection molding. The injection molding material indicated by dots, which is intended for the second portion 16 of the handle, is injected through an injection channel 18. The relatively high injection pressure also acts, when filling the recess 14 the outer side on the annular bead, as indicated by the two arrows Pf 2. The annular bead 15 to the relatively thin wall is pressed by the action of this injection pressure so that it is practically placed as a sealing sleeve sealingly around the carrier portion 5 therethrough and thereby actively preventing the injection molding material from penetrating and passing through the receiving opening 11. The sealing effect can be influenced by measurement variations of the annular bead.

Figures 12 to 15 show the manufacture of a round brush 1c, a shorter annular bead being provided here on the base body 9 of the handle unlike Figures 5 to 11. The end section 8 of the end 7 free of bristles of the carrier part is, therefore, at a distance from the inner end of the annular bead 15. The against-stop 13a is provided with an advance 19 to support the end of the carrying portion, which is directly forward adjacent to the end of the carrier portion (Figure 13) and whose withdrawal may be adjacent laterally to the annular bead 15. After the injection molding of the other portion 16 of the handle (Figure 15), the end 7 of the carrier part is fixed inside the portion 16 of the handle both in the axial direction and in the direction of rotation by its end section 8 folded in the shape of L.

Figures 16 to 19 show a progress of the finish in which the end section 8a is deformed hook-shaped, so folded several times. For such a deformation, the front sides of the folding slide 12a and against the abutment 13b, which are oriented towards each other, are provided in a manner approximately complementary to this hook shape of recesses and corresponding protuberances. . In this case too, the fixing of the end of the carrier part takes place by incorporation of its end section 8a in the portion 16 of the handle.

Figures 20 to 23 show the manufacture of the round brush 1b shown in Figure 3 which comprises a handle 3 and a brush portion 2 disposed at an angle relative to each other. A base body 9a of the handle is firstly molded by injection, comprising a reception opening 11 for the hairless end 7 of the carrying part 5. The brush blank 10 is then inserted with the end 7 of the carrier part in the receiving opening 11 and is folded several times with the aid of beach tools not shown here so that this end section 8b folded several times rests inside the recess 14. After the injection molding of the second portion 16 of the handle which preferably fills the recess 14, the terminal section 8b is fixed such that a separation without destruction of the handle 3 and the brush portion 2 is no longer possible. It should be mentioned that before the injection molding operation of the base body 9a of the handle, the brush blank 10 can be placed in the mold intended for its manufacture and be inserted by injection at the same time. In this case, it is possible for the deformation of the end section 8b to take place before the injection molding operation or after the injection molding operation. If a corresponding deformation is already provided before the injection molding operation, the handle 3 could also be manufactured as a one-component part by a single injection molding.

Fig. 24 shows a device 20 which is designed as a four station rotating mold comprising simple molds 21 which can be positioned in the four work stations I to IV for the manufacture of a round brush 1a. In station I, a brush blank 10 is first placed in such a manner that the hairless end 7 of its carrier portion projects into the mold cavity which is not shown in detail. In station II, the hairless end 7 of the brush blank 10 is recessed by injection and a base body 9 of the handle is thus formed. In the following station III, forming of the end section 8a is then carried out using the folding slide 12a shown in FIG. 16 and against the abutment 13b, and finally, in the station IV, the portion 16 of the sleeve is injection molded during a second injection molding operation. The deformed terminal section 8a, forming an anchor, is then immovably fixed. The removal of the round brush 1a completed and then the introduction of the next brush blank 10 take place in the next station I.

FIG. 25 shows a four-station rotary mold 25 comprising quadruple molds 23. Treatment or manufacture of four round brushes takes place simultaneously in each station I-IV. In the ejection station I, it is indicated by different hatches of the handle parts that different injection molding materials can be used for the handle parts. In station II, four handle base bodies 9 are first injection molded into the quadruple mold. The introduction of brush blanks with the hair-free end 7 of their carrier part into the receiving opening 11 then takes place in the next station III. After the formation of the hook-shaped end sections 8a in the recesses 14, the injection molding of the handle portion 16 takes place in the station IV and thus the integration of the hook-shaped end sections 8a. The round brushes 1a are then ejected at the station I.

FIG. 26 shows a rotating mold with three stations 22 respectively comprising sextuples molds 26 in which folded round brushes 1b are manufactured. In station I, the base bodies 9a of the sleeves are first injection-molded and in station II the end sections 8b of the hair-free ends 7 of the brush blanks previously inserted into the receiving openings 11 are distorted. In station III which follows, the handle portions 16 are finally injection molded to fix the folded end sections 8b and to fill the recess 14.

Claims (22)

Process for the production of brushes having a brush blank comprising a carrier portion (5) twisted into a wire with a head-side hair liner and a handle, characterized in that the blank Bristle brush (10) is connected to the first portion (9, 9a) of the handle of the brush leaving free an end section (8, 8a, 8b) of the end free of bristles. the carrier part (7) and in that then the end section (8, 8a, 8b) left free is deformed and enclosed by a second portion (16) of the handle (3) of the brush. A process for the production of brushes which have a brush blank (10) composed of a carrier part (5) twisted into a wire with a head-end hair lining (6) and a handle (3). ), characterized in that the brush blank (10) is deformed at the end section (8, 8a, 8b) of the hair-free end (7) of its carrier part and is then placed in a mold injection and in that at least a portion of the handle or handle (7) is injection molded and, in doing so, the end (7) of the carrier portion is embedded by injection at least at its end section (8, 8a, 8b) deformed. 3. Method according to claim 1, characterized in that the first portion (9, 9a) of the handle (3) of the brush comprising a receiving opening (11) for inserting the end (7) free of hair from the part carrier is first injection-molded, in that the hair-free end of the carrier part is then inserted into and through the receiving opening (11) and a free end section (8, 8a, 8b). protruding from the end (7) of the carrier portion is deformed and the second portion (16) of the handle (3) of the brush surrounding the deformed end section (8, 8a, 8b) is then preferably injection molded. 4. Method according to claim 1, characterized in that the brush blank (10) is embedded by injection with a first portion (9, 9a) of the handle (3) of the brush leaving free an end section (8, 8a, 8b) of the hair-free end (7) of its carrier part and in that the free end section (8, 8a, 8b) projecting from the end (7) of the carrier part is then deformed and then the second portion (16) of the handle (3) of the brush surrounding the deformed end section is preferably injection molded. The method of claim 2 or 4, wherein the brush blank (10) with head-end bristles is introduced with its hair-free end region into a passage of a portion of an injection mold. and is recessed by injection to form a brush handle (3), characterized in that the section of the passage aperture of the mold part is changeable and is reduced for tight and essentially tight holding of the end (7). ) and that the section of the opening of the passage of the mold part is enlarged after the injection molding of the handle (3) of the brush part (10). brush for removing the brush. 6. Method according to one of claims 1 to 5, characterized in that the free end section (8, 8a, 8b) protruding from the end (7) of the carrier portion is deformed by at least one simple folding. 7. Method according to one of claims 1 to 5, characterized in that the free end section (8, 8a, 8b) protruding from the end (7) of the carrier part is deformed by a fold-shaped hook. 8. Method according to one of claims 1, 3, 6 or 7, characterized in that the first portion (9, 9a) of the brush of the market is manufactured with a recess (14) which is within its scope longitudinal and wherein the end section (8, 8a, 8b) of the end (7) of the carrier portion is deformed and is incorporated in the second portion (16) of the handle (3) of the brush. 9. Method according to one of claims 1 to 8, characterized in that during manufacture, in particular the injection molding of the first portion (9, 9a) of the handle of the brush, an annular bead (15) is formed on the latter in the extension of the receiving opening (11) for receiving the hair-free end (7) of the carrying part which is opposite to the bristle packing, annular bead which, during the injection molding of the second portion (165) of the handle (3) of the brush and due to the external pressure exerted on the annular bead (15) by the injection molding, is deformed into a sealing collar and is pressed in a sealing manner around the end (7) of the carrier part. Apparatus for producing brushes having a brush blank comprising a carrier portion (5) twisted in wire with a head-side hair pad and a handle (3) connected to the hair-free end of the carrier part, in particular for the implementation of the method according to one of claims 1 to 9, characterized in that it has a deformation device for deforming an end section (8, 8a, 8b) of the end ( 7) free of bristles from the carrying portion passing through a first portion (9, 9a) of the handle (3) of the brush and a device for connecting the first portion of the handle of the brush to the second portion (16) of the handle of the brush and to surround the distorted end section (8, 8a, 8b) of the hairless end of the carrier part. 11. Device according to claim 10, characterized in that it has an injection molding device for manufacturing the first portion (9, 9a) of the handle of the brush and, preferably, an injection molding device for manufacturing the second part of the handle of the brush. Device according to claim 10 or 11, characterized in that the injection-molding device for the first part (9, 9a) of the brush handle is designed for housing and embedding by injection of the end ( 7) free from hairs of the carrier part leaving free its terminal section (8,8a, 8b). 13. Device according to one of claims 10 to 12, characterized in that the deformation device for deforming the end section (8 8a, 8b) of the end (7) free of bristles of the carrier part is preferably arranged near of the injection molding device for the first portion (9, 9a) of the brush handle. 14. Device according to one of claims 10 to 13, characterized in that the injection molding device for injection molding the second portion (16) of the handle of the brush is designed to insert by injection the terminal section (8, 8a, 8b) deformed from the end (7) free of bristles of the carrier part. 15. Device according to one of claims 10 to 14, characterized in that the deformation device is designed to fold once or more times the end section (8,8a, 8b) of the end (7) free of hair of the carrier part. 16. Device according to one of claims 10 to 15, characterized in that the deformation device has a folding slider (12, 12a) slidable laterally and transversely to the longitudinal extent of the end (7) of the carrier part. and also a counter-stop for the wire (13, 13a, 13b) which engages with the end (7) of the carrier part on the other side. 17. Device according to one of claims 10 to 16, characterized in that the bending slide (12, 12a) and / or the abutment (13, 13a, 13b) for the wire have on their sides a force on the blade. end (7) of the carrier part of the protuberances or notches in particular for the multiple folding of the end section (8, 8a, 8b) to deform the end (7) of the carrier part. 18. A round brush, in particular a twisted interdental brush, having a brush blank (10) composed of a wire-wound carrier portion (5) with a head-side hair pad and a handle (3) connected to the hair-free end (7) of the carrier part, in particular manufactured according to a method according to claims 1 to 9 by means of a device according to claims 10 to 17, characterized in that the end section (8, 8a, 8b) of the hair-free end (7) of the carrying part, which is in the handle (3), is deformed and is kept closed by shape connection inside the handle. Round brush according to claim 18, characterized in that the two-part handle (3) is preferably made of injection molded parts and that the end (7) of the carrier part which is deformed is embedded by injection into one of the parts of the handle. 20. Round brush according to claim 18 or 19, characterized in that the head-facing pile lining (6) and the handle (3) are arranged approximately in an aligned manner. 21. Round brush according to claim 18 or 19, characterized in that the head-facing pile lining (6) and the handle (3) are arranged at an angle to each other. Round brush according to one of claims 18 to 21, characterized in that the handle (3) of at least two parts consists in particular of at least two injection-molded components and that the basic body ( 9, 9a) of the handle comprising a receiving aperture (11) for the hair-free end (7) of the carrier portion having an annular bead therein protruding into another injection-molded portion, annular bead to which connects the deformation of the end section (8, 8a, 8b) of the end (7) of the hairless carrier portion which is surrounded by the other injection molded part.