Brush for a sonic toothbrush with longitudinal axis oscillation

Abstract

A brush (10) for a sonic toothbrush with longitudinal axis vibration and an elongated base body has a frustoconical foot section (11) with a drive adapter for rotationally fixed I <oppeln an einen Schallzahnbürstenantrieb mit Längsachsenschwingung, sowie einen I<opfteil (13) mit einem Borstenträger, in welchen eine Vielzahl von Borsten verankert ist, und einen länglichen Halsteil (12), der Fussteil (11) und I<opfteil (13) verbindet. Der Grundkörper bildet dahingehend einen Knick-Winkel, dass eine geometrische Fussteil-Längsachse (20) und eine geometrische Kopfteil-Ausrichtungsachse einen Winkel γ im Bereich von 5° bis 12° einschliessen. Eine geometrische I<nicl<position (22) im Grundkörper hat einen Abstand zu einer Endfläche des Fussteils (11) mindestens 50% einer Gesamtlänge des Grundkörpers.A sonic toothbrush with longitudinal axis vibration comprises a brush (10) and a handle with a brush head. <upplung zum lösbaren Befestigen der Bürste (10) am Handapparat, sowie einen Antrieb (16), der an der Bürstenl<upplung eine Längsachsenschwingung erzeugt.

Description

Technical area

[0001] The invention relates to a brush for a sonic toothbrush with longitudinal axis vibration, comprising an elongated base body which: has a truncated cone-shaped base part with a drive adapter for rotationally fixed coupling to a sonic toothbrush drive with longitudinal axis vibration; a head part with a bristle carrier in which a plurality of bristles are anchored; and which has an elongated neck part connecting the base part and the head part. State of the art

[0002] There are different types of electric toothbrushes.

[0003] From the publications DE 10 2016 011477 (Schiffer), EP 2'454'967 A1 (Braun), WO 2005 046508 A1 (Trisa), and others, the principle of the round brush head is known. This brush head can rotate about an axis parallel to the direction of the bristles and is moved back and forth about this axis. The advantage of this arrangement is that the moving part (namely the round brush head) is very small. It does not require much drive energy and does not generate any I <räfte (Drehmomente) sind tendenziell klein. Der Nachteil dieses Prinzips liegt darin, dass die Borstenbewegung abhängig ist von der Distanz zur Rotationsachse. Je näher die Borsten zur Achse des Bürstenkopfs sind, desto geringer ist die Hin- und Her-Bewegung. Das Bewegungsmuster ist also sehr inhomogen verteilt über das Borstenfeld.

[0004] From the publications JP H04-43127 (I <ao), US 2006 168744 A1 (Butler), US 2012 / 0291212 (Montagnino) und anderen ist das Prinzip der Pendelbewegung bekannt. Dabei pendelt die Bürste um eine Pendelachse, die senkrecht zum Handapparat (Antrieb) und zur aufgesetzten Bürste steht und die die Längserstreckungsachse von Handapparat und Bürste am Ort der Kopplung der Bürste an den Handapparat schneidet. Der Vorteil ist, dass die Bewegungsintensität über das ganze Borstenfeld homogen verteilt ist. Alle Borsten haben nämlich mehr oder weniger den gleichen Abstand von der Pendelachse. Der Nachteil besteht allerdings darin, dass relativ grosse Kräfte (Momente) auftreten, weil der Bürstenkopf mit seiner Masse relativ weit von der Pendelachse entfernt ist.

[0005] The principle of housing vibration is known from publications JP 2012-161368 (Sanion), DE 299 13 406 U1 (Rowenta), US 6,766,548 B1 (Rowenta), WO 2005 046508 A1 (Trisa), WO 2013 / 104020 A1 (Erskine), and others. A drive in the handset or brush neck generates an undefined vibration that is transmitted to the bristles. The advantage of this design is that there is no need to deal with the technical details of motion transmission. The disadvantage, however, is that the entire housing must be vibrated, and accordingly more drive energy is required than if only a small part needs to be vibrated. Furthermore, the vibration must not be too strong, as this impairs the comfort of holding the handset. Finally, the effective movements of the bristles are unknown and the cleaning effect of this type of undefined and uncontrolled vibration is anything but optimal.

[0006] Another principle is known from the publications WO 2012-151259 A1 (Water Pik), EP 2,548,531 B1 (Trisa), and others. Here, the handset has a coupling pin that rotates back and forth around its longitudinal axis. The brush, which is attached to the coupling pin, has a straight neck and a bristle plate at the end, the bristles of which are perpendicular to the longitudinal axis of the handset or brush neck. The advantage of this geometry is that relatively low forces (moments) occur because the mass (neck, bristle plate) of the brush attachment is relatively close to the longitudinal axis (center of movement). The movement intensity is also distributed relatively evenly across the bristle field. The disadvantage of this principle, however, is that the bristles only perform a one-dimensional movement (back and forth).On the one hand, the foaming effect of the toothpaste is unsatisfactory and, on the other hand, the advantage of the circular and thus gentle yet efficient movement, which specialists have been teaching for decades as being beneficial in connection with the manual toothbrush, is missing.

[0007] It is well known that the cleaning effect of manual toothbrushes depends on the hardness of the bristles. Bristles of different hardness have different cleaning effects and different damage potentials depending on their intended use. These effects are well known among experts and are regularly incorporated into patient consultations.

[0008] Sonic toothbrushes are very comfortable for the user and are also considered efficient because the electrically powered brush makes the movements much faster than you can do by hand.

[0009] When it comes to sonic toothbrushes, it has so far been assumed that the higher the frequency of the motor and the greater the cleaning movement of the bristles, the better the cleaning.

[0010] WO 2017 / 050612 A1 (Curaden) discloses a sonic toothbrush with an angled brush head. The forward angle of the sonic toothbrush allows for better access to various areas of the teeth. The angle also ensures that the brush filaments oscillate with a greater amplitude perpendicular to the brush's longitudinal axis. The preferred operating frequency is 2000 to 8000 hertz. However, frequencies can also be higher, for example, 10 kHz, 50 kHz, or even lower, for example, 200 Hz or 500 Hz.

[0011] US 2012 / 0291212 A1 discloses an ultrasonic toothbrush that has two parallel channels running perpendicular to the brush's longitudinal axis to increase the resonant frequency. The frequency is increased in a forward-backward direction when the two channels are positioned at the front. If the channels are positioned on the left and right sides of the brush neck, the frequency increases in a lateral direction. Disadvantages

[0012] There is still a lack of sufficient understanding of the cleaning behavior of sonic toothbrushes. Current knowledge regarding the cleaning effectiveness of manual toothbrushes cannot be transferred to the highly dynamic situation of a sonic toothbrush. Description of the invention

[0013] The object of the invention is to create a toothbrush for sonic toothbrushes belonging to the aforementioned technical field, which offers an improved cleaning effect that is particularly gentle on the gums. In particular, a defined and controlled two-dimensional movement of the bristles is to be generated.

[0014] The solution is defined by claim 1. The base body has a bending angle such that a geometric foot part longitudinal axis and a geometric I <opfteil-Ausrichtungsachse einen Winkel γ im Bereich von 5° bis 12° einschliessen. Zudem hat eine geometrische Knickposition im Grundkörper einen Abstand zu einer Endfläche des Fussteils von mindestens 50% einer Gesamtlänge des Grundkörpers.

[0015] The sonic toothbrush according to the invention essentially generates a vibration of the brush around its longitudinal axis, i.e., the longitudinal axis of the base (defined here as the x-axis). The bristles therefore primarily perform a wiping motion perpendicular to the aforementioned longitudinal axis. A particular advantage of the brush according to the invention is that it has a bending angle position that results in a sufficiently large deflection (also called eccentricity) of the head section, so that a certain vibration also occurs in the direction of the longitudinal axis. The result is a two-dimensional movement that can be described as a "figure-8" movement. This is particularly advantageous in several respects.

[0016] The combination of the special bending angle, which according to the invention is neither too small nor too large, and the bending angle position according to the invention, which is not too close to the base, results in a deflection (or eccentricity with respect to the base's longitudinal axis) and a leverage effect, which leads to a slight nodding movement of the brush head during operation. This results in the aforementioned two-dimensional "figure-8" movement of the bristle tips.

[0017] However, one advantage of this brush design is that the brush also performs a slight "noddling" motion toward the bristles. This pushes the mixture of saliva and toothpaste "forward" into the interdental spaces. This is especially important for single-tuft toothbrushes, which are specifically designed for better interdental cleaning.

[0018] The invention is based on the following basic features: a) The brush has a base part, on which an adapter to the handset, a so-called drive adapter, is formed. The adapter is geometrically designed to be connected in a rotationally fixed (but replaceable) manner to a coupling part (e.g. pin) of the sonic toothbrush drive. The sonic toothbrush drive generates a longitudinal axis vibration that is transferred to the brush. The drive adapter defines a geometric base part longitudinal axis (x) of the brush. This longitudinal axis is normally the direction in which the brush can be attached to the handset. b) The brush also has a head part with a bristle carrier in which a plurality of bristles are anchored (bristle field). The head part is essentially the upper end of the brush (whereas the base part forms the lower end). The head part defines an I <opfteil-Ausrichtungsachse. Die im Kopf verankerten Borsten ragen z.B. quer zur I<opfteil-Ausrichtungsachse weg.Typically, but not necessarily, the bristles are perpendicular to the I <opfteil-Ausrichtungsachse. c) Zwischen Fussteil und Kopfteil hat der Grundkörper einen Halsteil. Der Halsteil verbindet also Fussteil und Kopfteil miteinander. Er ist im Vergleich zum Fussteil querschnittsverjüngt. Das heisst, wenn man den Fussteil im Querschnitt (bezogen auf die Fussteil-Längsachse) betrachtet, dann sind die Abmessungen in x- oder y-Richtung kleiner als beim Querschnitt des Halsteils (also quer zur Halsteil-Längsachse). Dabei ist querschnittsverjüngt auf die Querschnittsfläche zu beziehen. Es ist also nicht zwingend, dass die Abmessungen in x-Richtung und y-Richtung geringer sind. .

[0019] In a first variant, the bristle carrier has several tufts, each with a large number of bristles. In a second variant, the bristle carrier has exactly one tuft with a large number of bristles (single-tuft variant).

[0020] However, the bristles can also be indirectly anchored to the surface of the bristle carrier, especially if the brush is designed as an interdental brush. In a third variant, the bristle carrier has a twisted or folded wire loop on its surface, with the bristles clamped between the strands. In this case, the I <opfteil-Ausrichtungsachse vorzugsweise rechtwinklig zur Drahtausrichtung ausgerichtet.

[0021] The geometric bending position is determined by an intersection point between the geometric foot part longitudinal axis and the geometric I <opfteil-Ausrichtungsachse definiert. An der geometrischen Knickposition muss also nicht zwingend ein knickartige (oder knieartige) Richtungsänderung des Grundkörpers vorhanden sein. Vorzugsweise befindet sich die geometrische Knickposition innerhalb des Grundkörpers. Die Form des Grundkörpers muss nicht zwingend einen optisch erkennbaren Knick umfassen, sondern kann zum Beispiel bogenförmig ausgebildet sein. In Varianten kann weiter die geometrische Knickposition auch ausserhalb des Grundkörpers liegen. Dem Fachmann sind weitere Variationen bekannt.

[0022] The distance between the end face of the foot section and the bending position is measured along the foot section's longitudinal axis. The total length of the base body is also measured along the foot section's longitudinal axis.

[0023] According to the invention, the geometric bending position has a relatively large distance from the head part in order to, in connection with the angle γ (gamma) between the geometric foot part longitudinal axis and the geometric I <opfteil-Ausrichtungsachse von 5° bis 12° einen besonders optimales Schwingungsverhalten zur Reinigung der Zähne zu erreichen. Je grösser der Winkel gewählt wird, desto stärker wird die Auslenkung des Kopfteils von der Fussteil-Längsachse (Exzentrizität). Ebenso wird die Exzentrizität grösser, wenn die Knickposition weiter von dem Kopfteil entfernt wird. Es hat sich aber gezeigt, dass die beiden Parameter (Knickposition und Winkel) das Schwingungsverhalten nicht in demselben Masse und in derselben Art und Weise beeinflussen, so dass hinsichtlich der Reinigungswirkung z.B.an increase in the angle cannot be directly compensated by a smaller distance between the bending position and the head part, since the 2-dimensional or 3-dimensional vibration pattern of the head part reacts differently to the two parameters.

[0024] The distance between the geometric bending position and the end surface of the foot section is preferably at least 60% of the total length of the base body. This defines a particularly optimal range for the geometric bending position, which, according to experiments, leads to particularly advantageous 2-dimensional or 3-dimensional vibration patterns. This allows for particularly effective yet gentle tooth cleaning.

[0025] In variants, the distance of the geometric bending position to the end surface of the foot part can also be between 50% and 60% of the total length of the base body.

[0026] According to a special embodiment, the distance between the geometric bending position and the end surface of the foot section is a maximum of 75% of the total length (L) of the base body. Within this upper-limited range, the inventive bending angle of 5° to 12° allows for a sufficiently strong "8" movement, allowing for considerable design flexibility regarding the geometric dimensions of the neck section and head section.

[0027] According to a special design, the head section is plate-shaped and the neck section is rod-shaped. The head section is thus in cross-section (i.e. in the plane perpendicular to the I <opfteil-Ausrichtungsachse) in der einen Richtung (z.B. y-Richtung) breiter als in der anderen Richtung (z.B. z-Richtung). Die Form des Querschnitts kann beispielsweise rechteckig, trapezförmig oder oval sein.

[0028] The neck section may be circular, oval, square, hexagonal, octagonal, trapezoidal, or a geometric approximation or modification of such a shape. The cross-sectional shape does not need to be rotationally symmetrical.

[0029] According to a first particular embodiment, the head part is at least about twice as wide as the neck part.

[0030] According to a second special embodiment, the head section is at most approximately 1.5 times as long as the neck section. This can also be combined with the previously mentioned embodiment.

[0031] According to a third particular embodiment, the head part is spanned in a cross section by the longitudinal axis of the brush and the I <opfausrichtungsachse etwa gleich dick wie der Halsteil. Ist der Kopfteil plattenförmig, dann ist also der Halsteil etwa gleich dick wie die I<opfteilplatte.

[0032] In one embodiment, the head section is at least about twice as wide and at most about 1.5 times as long as the neck section. Particularly preferably, the head section is between 2 and 3 times as wide and preferably between 0.5 and 1.5 times as long as the neck section. The relatively slender neck section, compared to the head section, achieves particularly good vibration behavior and thus optimal cleaning of the teeth.

[0033] In variations, the head section can also be less than twice as wide and more than 1.5 times as long as the neck section.

[0034] In a particular embodiment, the head portion has a mass that is greater than the mass of the neck portion; in particular, the head portion has a mass that is preferably more than 30%, particularly preferably more than 50%, greater than the mass of the neck portion. This mass distribution can be achieved either through appropriate geometric dimensions or through different materials, or through both.

[0035] The relatively large mass of the head compared to the neck allows for a slight nodding motion of the brush head (a movement in the z-direction) to be optimized when using the toothbrush. The larger mass increases the momentum of the nodding motion, which can reinforce the two-dimensional "8" motion and, in turn, better reach the interdental spaces. This is particularly advantageous, but not exclusively, with the single-tuft version or interdental brush.

[0036] In variants, the head section can also have a mass that is less than 30% greater than the mass of the neck section; in particular, the masses of the head section and the neck section can also be approximately the same. This is the case, for example, if the head section is the same thickness as the neck section, and if the neck section is three times as long as the head section, and the head section is three times as wide as the neck section.

[0037] Preferably, the base section is approximately the same length as the head section. This ensures that the base section is sufficiently large to ensure a stable attachment to the sonic toothbrush drive (e.g., with a long adapter channel for a correspondingly long handset pin). The vibration and thus the kinetic energy of the drive are efficiently transferred to the head section via the neck section.

[0038] In a special design, the base section is shorter than the head section; in particular, the base section is approximately half as long as the head section. This creates more design freedom for the neck section. If, in such a design, the drive adapter is also designed as a slender pin on the brush that inserts into an adapter channel in the handset, the stable attachment to the sonic toothbrush drive is concealed.

[0039] In some variants, the foot section can also be longer than the head section.

[0040] Preferably, the neck portion has a transverse dimension that is no more than one-quarter of the length of the neck portion. The transverse dimension is understood to be a diameter perpendicular to the geometric alignment axis or perpendicular to the foot portion's longitudinal axis. Where the neck portion connects to the head portion, the I <opfteil-Ausrichtungsachse massgeblich und dort, wo der Halsteil an den Fussteil anschliesst, ist die Fussteil-Längsachse massgeblich. Der Halsteil wird damit bewusst schlank gehalten, so dass damit das Schwingungsverhalten des Kopfteils unterstützt werden kann, insbesondere das Schwingungsverhalten in der Ebene (die "8"-Bewegung) und die Nickbewegung.

[0041] In some variants, the transverse dimension can also be more than a quarter of the length of the neck piece. This can be useful, for example, if a particularly flexible or elastic material is used for the neck piece.

[0042] Preferably, the base body is made of a load-bearing material with a Young's modulus of less than 8,000 MPa. In particular, the Young's modulus is in the range of 2,000 MPa to 6,000 MPa. This results in a base body that is sufficiently elastic to optimally transmit vibrations while also being sufficiently stable.

[0043] Preferably, the modulus of elasticity is at least 2500 MPa, in particular at least 3000 MPa. This ensures a base body that is sufficiently strong to optimally transmit the longitudinal axis vibrations.

[0044] In certain variants of the invention (e.g. at rather small bending angles in the range of 8°), the modulus of elasticity can tend to be lower (e.g. 2000 MPa to 3000 MPa) than at large bending angles (e.g. at 15°).

[0045] Another special design is characterized by the fact that the modulus of elasticity of the supporting material (or materials) of the base body is in the range of 4000 MPa to 6000 MPa.

[0046] If the mass of the head part is relatively large in relation to the cross-section of the neck part, then an elastic modulus in the range of 5000 MPa to 6000 MPa is advantageous.

[0047] Preferably, the base body consists essentially of a single piece made of a single material. This allows for particularly cost-effective production of the base body. It also enables particularly optimal vibration behavior, since no boundary transitions between different materials disrupt the vibration behavior, especially 2-dimensional or 3-dimensional vibration behavior, where such a boundary transition is bent in different directions by the vibration pattern.

[0048] For the purposes of the invention, a one-piece base body made of a supporting material is also referred to if the surface of the brush is coated or encased in a non-supporting material. For example, in a one-piece base body, areas made of a material with increased roughness or surface grip can be provided on the base part, so that the brush can be more easily removed from the drive pin with the fingers.

[0049] According to a special embodiment, the base body is essentially formed by two material parts joined together. For example, if the base part is molded from a different plastic than the neck and head of the brush, a very rigid plastic (with a high modulus of elasticity) can ensure that the coupling to the drive pin on the handset optimally transfers the drive movement to the brush. However, the neck can be designed to be sufficiently elastic using a less rigid material (the modulus of elasticity of the neck part material is lower than the modulus of elasticity of the base part).

[0050] Another special design is characterized by the fact that the base body is essentially formed by three materially bonded parts. For example, the base body can consist of two materially bonded parts of different strengths in the longitudinal direction. Furthermore, it is conceivable for the head section, neck section, and foot section to be made of different materials. The requirements for the head section are different from those for the foot section, which can be optimized by selecting the right material.

[0051] A base body made of two or three materially bonded materials is produced, for example, by modern plastic injection molding processes with two or three materials.

[0052] Non-load-bearing (e.g. soft) coating layers may also be present on the base body with the two or three load-bearing material parts in order to achieve certain functions (e.g. protection when the back of the brush comes into contact with the teeth).

[0053] Preferably, the head section has a deflection of 10% - 20% relative to the length of the brush. In this case, the deflection is defined as the ratio between the distance from the center (center of gravity) of the head section to the adapter's longitudinal axis, divided by the total length L (in the x-direction) of the base body. The deflection can be considered the "eccentricity of the head section with respect to the adapter's longitudinal axis." The deflection is crucial for the vibration pattern: it has been determined that with a deflection of 10% - 20%, the "figure-8" movement is particularly pronounced.

[0054] The deflection can also be less than 10% or greater than 20%. For brushes with a short overall length, the deflection is preferably selected in the range of 20% to prevent the head from becoming too small. For brushes designed for high operating frequencies (e.g., above 240 Hz), the deflection is preferably selected in the range of 10%, because at higher frequencies, the head's imbalance could otherwise become too large.

[0055] According to a special design, the bristles protrude essentially vertically from the I <opfteil-Ausrichtungsachse der Bürste weg. Der Winkel zwischen der Fussteil-Längsachse und der Borstenrichtung beträgt dann 90° minus Knickwinkel γ (gamma). Bei einem Knickwinkel von beispielsweise γ = 9° ergibt sich 90° - 9° = 81°.

[0056] The bristles are anchored, for example, to the main surface of the plate-shaped head. However, in a single-tuft brush, the head can also be rod-shaped, with the single tuft anchored in a cylindrical recess (e.g., a blind hole).

[0057] Preferably, a geometric foot part longitudinal axis and a geometric I <opfteil-Ausrichtungsachse einen Winkel γ (gamma) im Bereich von 7° bis 10° ein. Dieser Winkelbereich hat sich bei Experimenten als besonders vorteilhaft erwiesen, so dass damit für die Zahnreinigung ein besonders ideales Schwingungsbild erreicht werden kann. Experimente haben gezeigt, dass damit das Schwingungsbild, insbesondere die "8" Bewegung besonders vorteilhaft ausgeprägt ist, womit die Zahnreinigung mit der Bürste besonders schonend durchgeführt werden kann. Der Winkelbereich hat sich weiter im Zusammenhang mit der Auslenkung bzw. Exzentrizität des Kopfteils bezogen auf die Gesamtlänge der Bürste zwischen 10% und 20% als besonders vorteilhaft erwiesen und ebenfalls zu besonders guten Reinigungsergebnissen bei optimaler Ergonomie geführt.

[0058] The angle range of 7° - 10° in combination with a deflection of 10% to 20% leads to a good dynamic of the oscillation of the brush head in the sense of the desired "figure 8 movement".

[0059] In a special design, the neck section is tapered in cross-section compared to the head section. This means that the head section is wider and / or thicker (perpendicular to the I <opfteil-Ausrichtungsachse betrachtet) als der Halsteil. Damit wird der Halsteil mechanisch weniger steif als der Kopfteil (sofern der Grundkörper aus einem oder mehreren Materialien mit ungefähr gleichem E-Modul gefertigt ist).

[0060] A sonic toothbrush with longitudinal axis oscillation according to the invention comprises a brush according to the invention and a handset with a brush coupling for releasably attaching the brush to the handset and with a drive that generates a longitudinal axis oscillation at the brush coupling. The drive can, for example, comprise a piezo drive, a magnetic drive, and / or an electric rotary drive. A piezo drive is particularly preferred, in particular due to its simple design, particularly compact construction, and precise controllability.

[0061] The drive is preferably designed to generate a longitudinal axis oscillation frequency in the range of 150 Hz to 400 Hz. Since the brush generates a 2-dimensional or 3-dimensional movement pattern, the longitudinal axis oscillation frequency is set relatively low, allowing more time to perform multiple changes of direction per oscillation, e.g., in a figure-8 movement. The longitudinal axis oscillation frequency is advantageously no higher than 300 Hz. If the frequency is too high, the base body can no longer transmit the longitudinal axis oscillation generated by the drive to the brush head. This can lead to internal torsional movements, which can cause the head to, for example, only execute every other oscillation.

[0062] The longitudinal axis vibration frequency can also be less than 150 Hz, e.g. 120 Hz.

[0063] Preferably, the drive is designed to generate a longitudinal axis oscillation with an amplitude (deflection relative to a rest position) of less than 3°, in particular in the range of 1° to 3°. This means that the foot part is periodically rotated (moved back and forth) by the angle around the foot part's longitudinal axis. In variants, the amplitude can also be greater than 3°.

[0064] Further advantageous embodiments and combinations of features of the invention emerge from the following detailed description and the entirety of the patent claims. Short description of the drawings

[0065] The drawings used to explain the embodiment show: Fig. 1 is a schematic representation of a top view of a brush; Fig. 2 is a schematic representation of a side view of the brush; Fig. 3 is a schematic representation of a back view of the brush; Fig. 4 is a schematic representation of a top view of a sonic toothbrush comprising the brush; Fig. 5a is a schematic side view and a top view of a sonic toothbrush; Fig. 6 is a schematic representation of a side view of a sonic toothbrush with exactly one tuft; Fig. 7 is a schematic representation of the "8" movement according to the invention; Fig. 8 is a schematic representation of the angular amplitude of the longitudinal axis oscillation; Fig. 9 is an embodiment with an oval brush head; Fig. 10 is an embodiment of a single-tuft brush with a rear bristle field; Fig. 11 is an embodiment of a single-tuft brush with a front bristle field.

[0066] In principle, identical parts in the figures are provided with identical reference symbols. Ways to implement the invention

[0067] The Figure 1 shows a schematic representation of a top view of a brush 10. The brush 10 comprises a truncated cone-shaped base part 11, a rod-shaped neck part 12 adjoining the truncated cone-shaped base part 11, and finally a plate-shaped head part 13 adjoining the neck part 12. These three parts form the base body of the brush.

[0068] The truncated cone-shaped base part 11 comprises a drive adapter. In the present case, this is essentially formed by a channel-shaped receptacle 14 into which a pin of the handset of the sonic toothbrush can be inserted and locked (see below for Figure 4). The brush 10 has a base part longitudinal axis 20, which is aligned coaxially with the receptacle 14, or coaxially with the pin during operation of the sonic toothbrush. This longitudinal axis defines the x-axis of the xyz coordinate system used here. In other words: the drive adapter defines the geometric base part longitudinal axis (x) of the brush.

[0069] In the Figure 1 the bristle field 17 of the head part 13 is also visible, which in the present case has several (e.g. 20 - 40) tufts, each with a large number (e.g. 100 - 200) of bristles.

[0070] According to a preferred embodiment, the head section 13 is teardrop-shaped when viewed from the front. This means that its shape gradually widens – starting at the transition to the neck section – almost to the upper end of the head section, where it ends in a rounded final contour. With this shape (for a given length of the bristle field in the x-direction), the center of gravity of the head section 13 is closer to the end of the brush. This can enhance the eccentric effect at the specified operating frequency and thus also the "figure-8" movement.

[0071] The main surface of the plate-shaped head part 13 extends essentially transversely to the x-axis in the y-direction.

[0072] On the bristle field 17, an "8" lying in the y-direction is further depicted with the reference number 23. The "8" illustrates the movement, which is due to the selected material property (E-modulus), the angle between the geometric foot part longitudinal axis 20 and the geometric I <opfteil-Ausrichtungsachse (siehe weiter unten) und der Knickposition im Betrieb in der Ebene ausgeführt wird.

[0073] In addition to the figure-8, the brush also performs a slight nodding motion with the head section 13—this motion is essentially perpendicular to the figure-8, i.e., essentially in the z-direction. In a preferred embodiment, the bristles are thus moved in three dimensions (x, y, z).

[0074] The Figure 2 shows a schematic representation of a side view of the brush 10. In this figure, in addition to the geometric foot part longitudinal axis 20, the geometric I <opfteil-Ausrichtungsachse 21 ersichtlich. In der Darstellung gemäss Figure 1 are the foot part longitudinal axis 20 and the I <opfteil-Ausrichtungsachse 21 hintereinander. Die I<opfteil-Ausrichtungsachse 21 ist im Wesentlichen die Längsachse des Kopfteils. Die beiden Achsen schneiden sich in der geometrischen Knickposition 22. In der vorliegenden Ausführungsform schliessen die geometrische Fussteil-Längsachse 20 und die geometrische I<opfteil-Ausrichtungsachse 21 einen Winkel γ (gamma) von 10° ein. Die geometrische Knickposition 22 weist vorliegend einen Abstand K zu der Endfläche des Fussteils 11 von 50% der Gesamtlänge L der Bürste 10 auf. In dieser Kombination des Winkels zur Knickposition 22 wird eine Bürste 10 geschaffen, mit welcher eine besonders effektive und zahnfleisch-schonende Reinigung der Zähne möglich ist.

[0075] As the combination of Figures 1 and 2As can be seen, in the present embodiment, the head part 13 is plate-shaped and the neck part 12 is rod-shaped. In the projection of the base body onto the xz-plane, the head part 13 and the neck part 12 have the same transverse dimension (i.e. the same thickness). In the projection onto the xy-plane (front view according to Figure 1 ), the head section 13 is approximately three times as wide (y-direction) as the neck section 12. The length (x-direction) of the head section is approximately one-third greater than the width (y-direction). For example, the neck section 11 is one-third as wide and 1.5 times as long as the head section 13.

[0076] The neck part 12 is tapered compared to the head part 13 and the foot part 11. In the present example, the neck part 12 is in at least one of the side views (here in the z-direction according to Figure 1 viewed) less wide than the headboard 13.

[0077] In the present example, the base body of the brush 10 has as its supporting material a glass fiber reinforced polypropylene Borealis GB311U with an E-modulus of around 3500 MPA (Tensile Strength at yield = 97 MPa; Elongation at Yield = 2.8%; E-modulus = Tensile Strength at Yield / Elongation at Yield).

[0078] The deflection is determined by the ratio of distance A to the length L of the brush. The distance A corresponds to the distance from the front center of the head section (which here corresponds to the center of the bristle field 17) to the foot section's longitudinal axis 20 (see Figure 2 ). In this example, the deflection is 14%.

[0079] The bristles are arranged in several clusters and protrude vertically from the main surface of the plate-shaped head section. In this case, they are perpendicular to the y-direction and extend in the xz-plane. In the present embodiment, the bristles are attached to the front of the head section (or the front side 27 of the brush), i.e., they point slightly downward toward the adapter surface (yz plane) of the base section.

[0080] The Figure 3 shows a schematic representation of a back view of the brush 10 according to the Figures 1 and 2As can be seen from the figures, the base body has a different material on the back side 26, which is soft and provides protection (protective layer, protective coating) when the back of the brush comes into contact with the teeth. This material is non-load-bearing and can therefore have an elastic modulus outside the elastic modulus range of 2000-6000 MPa according to the invention. The load-bearing material is visible on the front side 27 and makes up a significant portion of the cross-section of the base body.

[0081] The Figure 4shows a schematic representation of a top view (z-direction) of a sonic toothbrush comprising the brush 10 and a handset 16 with a pin 15. The brush 10 is attached to the pin 15 so that the brush is detachable, rotationally fixed, and axially fixed. The handset 16 rotates the pin 15 back and forth at a frequency of, for example, 180 - 270 Hz with an amplitude of, for example, 2° (relative to a rest position) about the longitudinal axis of the pin 15 (which corresponds to the longitudinal axis of the handset 16). The brush thus rotates back and forth about the base part's longitudinal axis 20 (x-axis).

[0082] The Figure 5ashows a schematic representation of a side view of a sonic toothbrush 10. The sonic toothbrush 10 comprises a handset 16 and a brush 10. The drive of the handset 16 is designed as a piezoelectric drive (not shown), which generates an oscillation of the brush 10 about the x-axis 20 (longitudinal axis of the handset). Thus, during operation, the brush 10 executes a rotational oscillation about the x-axis 20 relative to the handle. Due to the inventive deflection of the head part 13, an imbalance arises, which has a movement component in the Y-direction 24 and / or in the Z-direction 25 (see below, Figure 5b ). This effect is controlled by the appropriately angled bend in the brush neck, the appropriately selected modulus of elasticity, and can be adjusted by other geometric design features of the brush (such as bend angle position, deflection, mass distribution, and other features according to the particular embodiments of the invention).

[0083] The Figure 5b shows a schematic plan view of a personal care device according to Figure 5a . In this illustration, the Z-direction 25 is visible. It runs essentially in the direction of the bristles. As can be seen from the figure, the handset is significantly larger than the brush. Only in this way can it generate a longitudinal axis vibration (instead of an undefined or undirected vibration movement, as is the case with conventional sonic toothbrushes).

[0084] The Figure 6 shows an embodiment of the sonic toothbrush, which comprises exactly one tuft 18. The tuft 18 is arranged at the rear of the head portion 13. The head portion is essentially tilted backward.

[0085] The Figure 7shows a schematic representation of the inventive "8" movement. The "8" movement in this case has the shape of a one-sidedly flattened "8," with an axis of symmetry (X-axis) running through the center 27 of the "8." The two loops 28a, 28b of the "8" extend in the y-direction. However, the invention is not limited to this exact form of the "8" movement; the exact form of the movement ultimately depends on the parameters of the brush head and the vibration generated by the handset motor.

[0086] The Figure 8 illustrates the amplitude of the longitudinal axis oscillation movement. The x-axis is perpendicular to the plane of the drawing. The plate-shaped head part 13 (shown without bristles) pivots around the x-axis by the angle α (alpha). (The bristles extend in Figure 8 (upward in the z-direction). The main component of the pivoting movement (and thus the bristle wiping movement) is in the y-direction. The angle α (alpha) is preferably 2°.

[0087] The Figure 9 shows a brush 10 with a plate-shaped oval head 13. The longitudinal axis of the oval shape runs essentially in the x-direction and the transverse axis in the y-direction. The center of the head 13 is further away from the upper end of the brush 10 than in the drop-shaped head according to Figure 1 .

[0088] Figure 10 shows a brush with a bending angle γ (gamma) of 14° and a distance K of the geometric bending position 22 to the end surface 29 of the foot part 11 of 75% based on the length L of the brush.

[0089] The base section 11 tapers from the end surface 29 to the transition into the neck section 12. The base section 11 can be, for example, truncated cone-shaped or truncated pyramid-shaped, with a concave profile in longitudinal section. Thus, the center of gravity of the base section 11 is closer to the end surface 29 than in a comparable base section with straight profile lines.

[0090] In the illustrated embodiment, the neck part 12 takes up approximately half the length (L) of the brush. Figure 10 As illustrated, the neck portion 12 does not necessarily have to have a constant cross-section along its entire length. It may well have a changing contour.

[0091] The head part 13 is formed by the extension of the neck part 12. In the present example, the head part 13 has essentially the same transverse dimensions (in a section perpendicular to the I <opfteil-Ausrichtungsachse 21 betrachtet) wie der Halsteil 12. Das Borstenfeld 17 ist seitlich am Kopfteil 13 platziert. Die Borsten stehen also senkrecht zur I<opfteil-Ausrichtungsachse 21 ab.

[0092] Figure 11shows an embodiment in which the base section 11 is essentially formed by a pin 30 as a drive adapter. The neck section 12 is rod-shaped and occupies, for example, 90% of the brush length. The head section 13 is the part in which the bristle field 17, here in the form of a single tuft, is anchored. The pin 30 is inserted into the handset in the x-direction for rotationally fixed coupling to a sonic toothbrush drive with longitudinal axis oscillation, with the drive adapter defining the geometric longitudinal axis (x) of the brush's base section.

[0093] A brush according to Fig. 11 For example, it is made of a material with a Young's modulus of approximately 4600 MPa. An example of such a material is LNP ULTEM ®< EXCP0096 Polyetherimide, 30% Carbon Fiber Reinforcement, 10% PTFE Lubricant (Tensile Strength at Yield = 163 MPa, Elongation at Yield = 3.5%, Tensile Strength / Elongation = 4650 MPa).

[0094] Variations of the embodiments: In further embodiments not shown, the brush 10 has an interdental brush for cleaning the spaces between the teeth instead of the bristle area 17. In summary, it can be stated that the invention provides a brush for a sonic toothbrush drive, which results in a particularly advantageous movement of the head section for effective, gum-friendly cleaning of the teeth.

Claims

1. Brush (10) for a sonic toothbrush with longitudinal axis vibration, comprising an elongated base body, which a) has a truncated cone-shaped base part (11) with a drive adapter (14) for rotationally fixed coupling to a sonic toothbrush drive with longitudinal axis vibration, wherein the drive adapter (14) defines a geometric base part longitudinal axis (x) of the brush, b) a head part (13) with an I <opfteil-Ausrichtungsachse (21) und einen Borstenträger hat, in welchen eine Vielzahl von Borsten verankert ist, c) und der einen im Vergleich zum Fussteil querschnittsverjüngten Halsteil (12) hat, der Fussteil (11) und Kopfteil (13) verbindet, characterized in thatd) the base body forms a bend angle such that a geometric foot part longitudinal axis (20) and a geometric I <opfteil-Ausrichtungsachse (21) einen Winkel γ im Bereich von 5° bis 12° einschliessen, und e) eine geometrische Knickposition (22) im Grundkörper einen Abstand (K) zu einer Endfläche des Fussteils (11) von mindestens 50% einer Gesamtlänge (L) des Grundkörpers hat.

2. Brush (10) according to claim 1, characterized in that the distance (K) of the geometric bending position (22) to the end surface of the foot part (11) is at least 60% of the total length (L) of the base body.

3. Brush (10) according to claim 1 or 2, characterized in that the distance of the geometric bending position (22) to the end surface of the foot part (11) is at most 75% of the total length (L) of the base body.

4. Brush (10) according to one of claims 1 to 3, characterized in thatthe head part (13) is plate-shaped and the neck part (12) is rod-shaped, wherein preferably a) the head part (13) is at least about twice as wide as the neck part (12) and / or b) the head part (13) is at most about 1.5 times as long as the neck part (12) and / or c) the head part (13) in a cross-section spanned by the longitudinal axis (x) and the I <opfausrichtungsachse etwa gleich dick gleich dick wie der Halsteil ist.

5. Brush (10) according to one of claims 1 to 4, characterized in that the head part (13) has a mass which is greater than a mass of the neck part (12), in particular the head part (13) has a mass which is at least 30%, particularly preferably at least 50% greater than the mass of the neck part (12).

6. Brush (10) according to one of claims 1 to 5, characterized in that the foot part (11) is approximately the same length as the head part (13).

7. Brush (10) according to one of claims 1 to 6, characterized in thatthe neck part (12) has a transverse dimension which is not more than a quarter of a length of the neck part (12).

8. Brush (10) according to one of claims 1 to 7, characterized in that the base body comprises a load-bearing material with a modulus of elasticity of not more than 6000 MPa and not less than 2000 MPa.

9. Brush (10) according to claim 8, characterized in that the modulus of elasticity is at least 2500 MPa, in particular at least 3000 MPa.

10. Brush (10) according to claim 8, characterized in that the base body consists essentially of one piece of material.

11. Brush (10) according to one of claims 8 or 9, characterized in that the basic body is essentially formed by two or three material parts that are joined together.

12. Brush (10) according to one of claims 1 to 10, characterized in that the head part (13) has a deflection of 10% - 20% relative to a length of the brush (10).

13. Brush (10) according to one of claims 1 to 11, characterized in that the bristles are essentially perpendicular to the I <opfteil-Ausrichtungsachse (21) der Bürste (10) weg ragen, 14. Brush (10) according to one of the preceding claims 1 to 13, characterized in that the geometric foot part longitudinal axis (20) and the geometric I <opfteil-Ausrichtungsachse (21) einen Winkel γ im Bereich von 7° bis 10° einschliessen.

15. Brush (10) according to one of claims 1 to 11, characterized in that The neck part (12) has a tapered cross-section compared to the head part.

16. Sonic toothbrush with longitudinal axis vibration, comprising a) a brush (10) according to one of claims 1 to 9 and b) a handset with a brush coupling for releasably fastening the brush (10) to the handset and with a drive (16 in the handset) which generates a longitudinal axis vibration at the brush coupling.

17. Sonic toothbrush according to claim 10, characterized in thatthe drive (16) is designed to generate a longitudinal axis vibration frequency in the range of 150 Hz to 400 Hz.

18. Sonic toothbrush according to claim 10 or 11, characterized in that the drive (16) is designed to generate a longitudinal axis oscillation with an amplitude of less than 3°, in particular from 1° to 3°.

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