The present invention refers to a toothbrush with an elongate handle stem and a brush head connected to the handle stem, which carries a bristle array containing a plurality of bristle bundles.
Such brushes are generally known. There are various designs of bristle arrays, each of which should be optimized with regard to the desired cleaning effect.
The present invention is based on the problem of providing a brush whose cleaning effect is improved and which is particularly suitable for cleaning the interdental spaces in the context of dental care.
To solve this problem, the present invention proposes a toothbrush with the features of claim 1. The toothbrush according to the invention has specially formed bristle bundles at the outer edge of the bristle array. The bristle bundles have a diameter of between 0.8 mm and 1.2 mm. They may alternatively be formed of microfilaments with a diameter of between 4 and 6 mils, these microfilaments being tapered to a tip at their usage ends. Bristle filaments which are tapered to a tip in the sense of the present invention are in particular those filaments with a filament diameter of 4 mm to 6 mils, the usage end of which tapers continuously towards a tip over a length of between 2 mm to 8 mm. The tip is usually located in the center of the filament.
The bristle bundles, which have a diameter of between 0.8 mm and 1.2 mm, preferably 0.9 to 1.1 mm, particularly preferably 0.8 to 1.0 mm, i.e. bristles of small diameter, can penetrate the interdental spaces in a special way and clean them particularly effectively. The same applies to the microfilaments, which according to the invention have a very small diameter and are also tapered so that these microfilaments can easily penetrate into the interdental spaces.
The bristle bundles specially formed in this way and provided at the edges are usually made of PBT. They usually accommodate conventional bristle bundles formed from PA between them. These bristle bundles can form a bristle array on the brush head in a manner known per se. They usually consist of filaments with a diameter of 5 to 8 mils.
A bristle bundle consists of at least two filaments. The bristle bundles are usually held by an anchor on the brush head. As far as the present invention refers to the number and length of the filaments, this specification refers to the filament in the processed state. It is not decisive that two filaments are formed from a piece of filament approximately twice as long and are wound around the anchor. These two filaments formed from an identical piece of filament are two filaments in the sense of the present invention. The length of the filaments is the length which the filament has measured from the surface of the brush head through which the filament passes to the usage end of the filament.
The bristle bundles provided at the outer edge of the bristle array are usually of a different color than the usually conventional bristle bundles provided between the edge bristle bundles. These conventional bristle bundles may form an inner bristle array with the usage ends lying in a single plane. This makes it possible to place the usage ends of the inner bristle array flat against the teeth, while at the same time the bristle bundles provided at the outer edge of the bristle array, which preferably project at least with their tips beyond the usage ends of the inner bristle array, can penetrate into the interdental spaces. Preferably the bristle bundles provided according to the invention at the outer edge of the bristle array are provided circumferentially. In other words, all bristle bundles provided at the outer edge of the bristle array are provided with a diameter of between 0.8 mm and 1.2 mm and/or formed by microfilaments with a diameter of between 4 and 6 mils, in order to form, for example, a bristle bundle tapering to a tip at the usage end.
The microfilaments form a bristle bundle contoured at the usage end of the bristle bundle. They are tapered to a tip, i.e. the microfilaments do not have the same length. Rather, one or a few of the microfilaments are longer than the adjacent microfilaments. Usually the longer microfilaments are provided in the center of the bristle bundle. However, eccentric bristle bundles are also conceivable in which the microfilaments at the edge of the bristle filament have the greatest length extension and the adjacent microfilaments are shorter.
The bristle bundle with a diameter of between 0.8 mm and 1.2 mm also preferably has a corresponding tapered contour in the sense discussed above. Thus, as a rule, few bristle filaments project over the usage ends of the inner bristle array and can effectively clean the interdental spaces when the usage ends of the filaments of the inner bristle array lie flat against the teeth, while in parallel the usage ends of the inner bristle array lie flat against the teeth and clean them.
Practical tests carried out by the applicant with a design in which all bristle bundles at the edges are formed in the manner described above have shown a considerably improved cleaning effect compared with conventional brushes with identical or similar bristle arrays.
The lower limit of the diameter of the small diameter bristle bundles is preferably 0.85 mm, especially preferred 0.9 mm. The upper limit of the diameter is preferably 1.05 mm, especially preferred 1 mm. Alternatively or in addition the microfilaments can have a diameter of 5 mils.
In so far as the bristle bundles at the edges of the bristles have been referred to above, this indication refers only to the arrangement of bristle bundles on the bristle head, these bristle bundles being formed by filaments. Generally, cleaning elements made of TPE are also known to be arranged on a brush head. Usually, these TPE cleaning elements, which may be additionally provided in the invention, are also provided by overmolding on a base body of the brush head. The cleaning elements are made of a soft-elastic component, preferably TPE. Such a soft-elastic overmolding can be provided on the outer circumference of the brush head in order to protect the sensitive gums when brushing the teeth and/or to form a tongue cleaner on the circumferential edge of the brush head or on the rear side of the brush head opposite the surface through which the bristle bundles project. For this purpose, the soft-elastic overmolding on the rear side preferably forms a profile which regularly has nubs and/or lamellae which can clean the tongue by scraping. The circumference of the brush head is usually formed by an edge of the brush head extending essentially at right angles to the surface through which the bristle bundles project. This edge connects the surface to the back of the brush head.
The soft-elastic overmolding can also form cleaning elements on the brush head. These cleaning elements project over the surface projected through by the bristle bundles. The soft-elastic cleaning elements can be provided on the edge of the brush head. Accordingly, the soft-elastic cleaning elements are sometimes located outside the bristle array and thus outside the bristle bundles provided at the outer edge of the bristle array. Soft-elastic cleaning elements can also be integrated into the bristle array. The soft-elastic cleaning elements are usually injected through indentations in the brush head at its edge and/or through holes in the brush head and are preferably connected to the brush head in a bonded or form-fit manner.
The soft-elastic material is usually injected via an injection point against a base body, which usually forms essential areas of the brush head and handle stem in one piece. This base body is made of a hard component, for example PA, PP or PE. The base body usually also forms the surface through which the bristle bundles project and accommodates anchors which attach the individual bristle bundles to the brush head. As already mentioned, the anchors attach at least the small diameter bristle bundles or the bristle bundles formed with the microfilaments. The conventional bristle bundles can also be fixed with anchors. Alternatively, the conventional bristle bundles can also be fixed to the brush head without anchors by first melting the conventional bristle bundles on the fixing side and then inserting them with the thickening thereby formed into a cavity which forms the base body. The bristle bundles are connected without an anchor to the base body, the plastic mass of which flows around the ends of the bristle bundles on the fixing side and seals the thickening in a form-fit manner.
The base body usually forms the skeleton of the brush body. A joint can be formed between the handle stem and the brush head. This is usually done by reducing the cross-section of the base body in such a way that a joint is formed between the brush head and the handle stem. This area with a reduced cross-section is preferably covered by the soft-elastic overmolding, so that an aesthetically pleasing appearance is achieved and it is also prevented that dirt and bacteria in the area of the joint adhere to the surfaces of the base body and settle in the area of the joint. The overmolding of the joint and the soft-elastic overmolding of the edge and/or the formation of the soft-elastic cleaning element is usually carried out by a uniform soft-elastic plastic material, by which all the aforementioned functional elements of the brush body are formed as a unit and connected to each other.
With regard to the desired improved cleaning effect, it has proven to be advantageous to form the bristle array with at least two circle segments. These circle segments usually have a center angle of at least 200°. The circle segments usually comprise bristle bundles concentric to the center point. Thus, each circle segment has one, preferably a plurality of concentrically arranged rings or partial rings of bristle bundles. The center of the circle segment can either be surrounded by an inner ring of bristle bundles at a small distance. Alternatively, a single bristle bundle may be present in the center point, surrounded by at least two further rings of bristle bundles. The outer ring of this arrangement is usually formed by the bristle bundles with a diameter of between 0.8 mm and 1.2 mm and/or by bristle bundles of microfilaments which are tapered to a tip at the usage ends of the bristle bundle.
The circle segments usually have inner rings formed by conventional bristle bundles, which can be formed by filaments with a diameter of between 5 and 8 mils. Usually only the outer ring is formed by small diameter and/or tapered microfilaments. However, it is also possible to form not only the outer edge but also the adjacent ring or ring segment wholly or partially by the small diameter or tapered microfilaments. Individual bristle bundles can consist exclusively of the microfilaments. A bristle bundle can also contain both conventional bristle filaments and tapered microfilaments. Bristle bundles formed from tapered microfilaments can also alternate with conventional bristle bundles in the circumferential direction. This does not necessarily mean that every first bristle bundle is formed in the circumferential direction like every third bristle bundle and between them the second and fourth bristle bundles. Rather, certain circumferential portions may have multiple bristle bundles formed of microfilaments and/or small diameter bristles and other circumferential portions may have bristle bundles formed of conventional bristle filaments.
A circle segment according to the preferred design discussed above has a center angle of at least 180°. The circle segment formed by bristle bundles with concentrically arranged bundles is therefore at least a semicircle. Furthermore, the angle of the center is at least 220°, further preferred 240° and especially preferred 280°.
According to another preferred design of the present invention, the brush head carries a first and a second bristle array. These bristle arrays are spatially separated from one another, i.e. macroscopically recognizable as separate bristled areas. One of the two bristle arrays is usually circular in shape and has between two and four rings of bristle bundles arranged around the center of the circle. The two bristle arrays have at their edges a plurality of bristle bundles with a diameter of between 0.8 mm and 1.2 mm and/or bristle bundles formed from microfilaments, the microfilaments each being tapered to a tip at their usage ends.
The filaments of these conventional bristle bundles can form a bristle bundle that is contoured on the usage side. In other words, the usage ends of the filaments of a single bristle bundle are located in different planes, wherein the plane is perpendicular to the direction in which the filaments extend. To satisfy this criterion, it is sufficient for two filaments of a bristle bundle to be of different lengths so that the usage ends of all bristle bundles are in either the first or second plane. The shortest bristle filament may have its usage ends below a plane in which the tapered microfilaments are still generally cylindrical. The shortest bristle filament of a conventional bristle bundle can also end above this plane. The longest bristle filament of a conventional bristle bundle can end below a plane up to which all the tapered microfilaments are cylindrical. The longest filament can also end above this plane. The contoured conventional bristle bundle should have a length spread of 1.05 to 1.2, preferably 1.1 to 1.15. The length spread defines the ratio of the longest bristle filament compared to the shortest filament of an identical bristle bundle.
When bristle arrays are arranged in at least two circle segments, the bristle bundle provided near the front free end of the brush head usually has a smaller outer diameter than the circle segment shaped bristle bundle displaced further back in the direction of the handle stem. The width of the brush head at the front end is correspondingly reduced. The brush head is preferably narrower at the front end than at the rear end of the brush head near the handle stem. The outer contour of the brush head should follow the contour of the bristles on the brush head. The brush head has correspondingly circle-segment-shaped brush head areas, each of which is equipped with the circle-segment-shaped bristle arrays. Thus the outer edge of the brush head follows the contour of the base area of the individual bristle arrays. The projection of the brush head, i.e. the clear distance between the bristle bundle at the outer edge of the bristle array and the edge of the brush head is in any case essentially identical in sections. In sections means here that the projection is constant at least with a center angle of at least 45°, preferably 60°, particularly preferably 80°. It goes without saying that there is a larger projection between individual bristle arrays formed as circle segments. Sometimes there are also webs between individual bristle arrays formed as circle segments, which extend transversely to the longitudinal extension of the handle stem and do not carry bristle bundles.
Further details and advantages of the present invention result from the following description of an embodiment in connection with the drawing.
The brush head 6 in the embodiment shown is formed by three basically circular and interlocking disc segments 12, 14, 16 whose diameter increases from front to back. The first disc segment 12 then has a smaller diameter than the second disc segment 14, which in turn has a smaller diameter than the third disc segment 16. The first disc segment 12 is equipped with a large circular bristle bundle 18, which is formed from conventional filaments with a diameter of 5 to 8 mils and is the only bristle bundle of the first disc segment 12.
The second and third disc segments 14, 16 are each provided with an arrangement of bristle bundles 8 arranged concentrically with respect to each other, wherein a bundle arrangement 20 provided on the second disc segment 14 carries two circular bristle arrays 22, 23 and the third disc segment 16 carries three such circular bristle arrays 24, 25, 26. The respective outer circular bristle array 22 and 24 is formed by bristle bundles 36 having a diameter of between 0.8 and 1.2 mm and being formed of microfilaments having a diameter of not more than 6 mils. This outer bundle array 20, 24 concentrically surrounds bundle arrays 23, 25 and 26, which are formed by conventional bristle bundles 38, 40 and 42, respectively. The bristle filaments forming the bristle bundles 36 have a maximum length of 14 mm. The conventional bristle bundles are between 9 and 11 mm long. This length is measured from the surface 10 projected through by the bristle bundles to the ends of the bristle bundles on the usage end. Bristle bundles 38 and 40 also have a diameter of between 1.2 and 0.8 mm.
In the top view according to
The front disc segment 20 is equipped with three rings R1 to R3 of bristle bundles 50, 52, 54 to form a second bristle array 48. As with the rear disc segment 30, the rings R1 to R3 are also provided concentrically to each other. The rings R1 to R3 are circular in each case. The innermost ring R3 has only two bristle bundles 54. The projection marked with reference numeral 56 in
All bristle bundles form a cleaning-active surface of the toothbrush with their ends on the usage side. This cleaning-active surface is convexly curved for the first bristle array 46 in side view. In other words, the bristle bundles 36 to 44 of the first bristle array 46 central in the longitudinal extension have a greater length than the front and rear bristle bundles, independent of the assignment of the respective bristle bundles 36 to 44 to their respective rings R1 to R4. The front bristle array 48 is also curved in a corresponding manner, whereby this front bristle array forms a cleaning-active surface which rises slightly towards the front. The cleaning-active surface of the second bristle array 48 is inclined forward by about 10 to 20° in side view, so that the bristle bundles 50 to 54 arranged in longitudinal direction at the free end of the brush head 6 have a greater length than the bristle bundles of the second bristle array 48 arranged towards the first bristle array 46.
The cleaning-active surface of the second bristle array 48 is only slightly convex curved. Longitudinal sections through the second bristle array 48, i.e. sectional views transverse to the longitudinal extension of the handle stem 4, show a flat, cleaning-active surface formed by the second bristle array 48.
On the other hand, the first bristle array 46 also has a contouring in the cross-sectional view. The contouring is concave. In other words, the bristle bundles (e.g. 44) in the center of the cross-sectional view are shorter than the outer bristle bundles (e.g. 36 in a cross-sectional view through the center of the first bristle array 46). The outer bristle bundles protrude a few tenths of a millimeter ( 2/10 to 8/10 mm) beyond the central bristle bundles.
The bristle bundles 38-42 arranged on the rings R2 to R4 of the first bristle array 46 and also the bristle bundle 44 or the bristle bundles 50-54 arranged on the rings R2 to R3 of the second bristle array 48 are conventional. The conventional bristle bundles are all identically formed. The bristle bundles 36 and 50 arranged on the outer rings R1 each consist of microfilaments with a diameter of 6 mils, which are tapered at their usage ends. The usage ends of these microfilaments project beyond the usage end filaments of the remaining bristle bundles of the first and second bristle array 46, 48.
The respective rings R1 to R4 or R1 to R3 are each designed as circumferentially closed rings. Thus the first and second bristle arrays 46, 48 each have a center angle of 360°.
While in the embodiment shown in
In this embodiment, the bristles have a wrapping of bristle bundles 62, which are formed by microfilaments with a diameter of 6 mils, wherein the microfilaments of the bristle bundles 62 are tapered to a tip at their usage end and are thus “tapered”. Inner bristle bundles 64, surrounded by these outer bristle bundles 62, form a flat cleaning-active surface extending parallel to the surface 10. The ends of the outer bristle bundles 62 protrude over this cleaning active surface.
The bristle arrangement of the embodiment according to
The central circular bristle array 64, formed by the conventional bristle bundles 60, has no outer bristle bundles 62, which are provided in the form of segments of a circle and formed of microfilaments, but two outer bristle bundles 62, formed of microfilaments, are located diametrically opposite each other on the outer ring R1 of the central bristle array 68.
In the embodiment shown in
In the embodiments in
Although
The topography sketched in
The inner bristle bundles 38 of the first bristle array 46 form a concave shaped cleaning-active surface. Its lowest point is located in the center of the outer ring R1.
The bristle filaments of the second bristle array 48 lying within the outer ring R1 form a planar cleaning-active surface which extends substantially parallel to the surface 10 of the brush head 6, but lies below a plane in which the usage ends of the bristle bundles 36 lie on the outer ring R1.
The bristle bundles 36 lying on the outer ring R1 each have identical lengths, whereby the bristle bundles 36 of the first bristle array 46 have identical lengths as the bristle bundles 36 of the second bristle array 48.
Number | Date | Country | Kind |
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10 2017 220 748.5 | Nov 2017 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2018/081852 | 11/20/2018 | WO | 00 |