EP2884869A2

EP2884869A2 - Tooth-brushing appliance including multiple rotary brushing systems

Info

Publication number: EP2884869A2
Application number: EP13762173.6A
Authority: EP
Inventors: Patrick Arnoux; Gérard Flavien
Original assignee: Dental Revolution Sas
Current assignee: Dental Revolution Sas
Priority date: 2012-08-20
Filing date: 2013-08-19
Publication date: 2015-06-24
Also published as: WO2014029945A2; FR2994526A1; FR2994526B1; WO2014029945A3

Abstract

The invention relates to a tooth-brushing appliance including multiple rotary brushing systems. The appliance comprises a body having a head (1) secured thereto, said head being provided with adjacent counter-rotating brushes (2, 2') having a substantially cylindrical external shape and parallel longitudinal axes. Each brush (2, 2') is rotated by a shaft (4, 4') and supported at each end by a bearing (3, 3', 5, 5') forming part of a support (6) that defines the gap between the longitudinal axes of each of the brushes. The support (6) comprises at least two flexible arms (6a, 6b, 6c, 6d) oriented substantially perpendicularly to the longitudinal axes, such that the respective ends thereof form the aforementioned bearings, said flexible arms being linked to a base (6e) used to secure the support (6) to the head (1). According to the invention, the brush (2) is formed by bristles oriented perpendicularly to the longitudinal axis XX' of the brush, said bristles having different lengths, so as to form at least one brush zone having a reduced cross-section in relation to the generally cylindrical cross-section of the brush.

Description

TOOTH BRUSHING APPARATUS WITH MULTIPLE ROTATING SYSTEMS

BRUSHING

TECHNICAL FIELD OF THE INVENTION

The invention relates to the field of oral hygiene and more particularly to toothbrushing apparatus having several rotary brushing systems. The invention may optionally relate to an animal use.

In all cases it is to achieve a particular brushing of the teeth, specifically a brushing from the gum to the end of the teeth that is to say from top to bottom for the upper and lower dentition at the top for the lower teeth. This type of brushing has proven to be the most effective for some time now.

STATE OF THE PRIOR ART

[0003] Thus, documents describe toothbrushes with multiple rotary brushing systems. By "rotary brushing system" is meant a brush or brush of cylindrical outer shape and consisting of radially oriented bristles, ie perpendicular to its longitudinal axis.

EP 0 488 971 discloses an electric toothbrush of this type, comprising two brushes rotating counter-rotating and arranged to act on the same blank of the dental arch. In this case one of the brushes works in the 'right' direction of brushing but the other operates unfortunately in the 'wrong' sense, bringing the impurities to the inside of the dentition instead of expelling them.

This type of toothbrush is not an optimal efficiency. [0006] Other toothbrushes with multiple rotating brushing systems are known: the document FR 2 489 120 describes cylindrical brushes with parallel axes, having rotational movements in opposite directions and arranged to insert between them the teeth to be cleaned. , so that they are brushed in the 'right' direction, that is to say from the gum to the end of the teeth. The spacing between the axes of the brushes is chosen so as to correspond to the average width of the teeth, increased by a few millimeters; moreover, the rotary axes are fitted into the body of the toothbrush and are free at their distal ends. This can be a disadvantage in that the free ends are easily deformable and more fragile.

[0007] Patent CH 644 256 shows an electric appliance for brushing teeth comprising two brushes with parallel axes, which engage in the body and which are rotated in opposite directions. The axes or rods of each brush have a conical section whose elasticity makes it possible to obtain a certain pressure against the teeth sandwiched between the brushes. Interestingly, a bending of the housing around its axis theoretically causes the appropriate rotation of the brushes; and return springs simultaneously provide the function of electrical conductors and switches. This device has the disadvantage of being rather sophisticated and impose a specific position of the brushes relative to the dental arch to clean.

EP 0 108 097 B1 discloses an electric brushing apparatus provided with three rotating brushes housed in a rigid casing enveloping. The three brushes have a cylindrical outer shape; two of them intended to be in contact with the flanks of the teeth, have a larger diameter than the third brush intended to come into contact with the end face of the teeth. It is understood that such a device has the particular disadvantage of the lack of efficiency of the end brush which is also provided with a direction of rotation antagonistic to that of the side brushes; this end brush therefore determines a given application height of the device which is not necessarily appropriate because it does not allow an action on the full height of all the teeth, including the gum.

[0009] Patent EP 0 725 602, which describes a toothbrush with a double rotary brushing system, comprising a sleeve body on which is fixed a head provided with two counter-rotating brushes of cylindrical outer shape, adjacent to each other. parallel axes, supported at each of their ends by bearings; the trees that carry the brushes are flexible and the bearings mounted on a support common to both brushes, allow a certain effect of return and maintenance of the brushes relative to each other.

Furthermore, known devices in the field of toothbrushes with multiple brushing systems have cylindrical outer shape brushes. They are therefore built-in, radially oriented, and constant length bristles which form such brushes. In this way, the brushes being at a given distance from the teeth, the forces exerted by the brushes on the teeth are constant throughout their rotation; this is interesting but can be improved to achieve a different effect on the teeth. It is particularly interesting to have a massaging effect on the teeth and gums; it is also interesting to create the same effort on the teeth and the junction areas between the teeth, which by their geometry are not at the same distance from the axis or axes (rectilinear) of each brush; The known brushes generate a variable effort on the different areas that they sweep and these efforts are not necessarily appropriate.

SUMMARY OF THE INVENTION

The invention aims to overcome the drawbacks of the state of the art and in particular to provide a device for brushing teeth with multiple rotary brushing systems, comprising a body on which is fixed a head provided with counter-rotating brushes, adjacent, of substantially cylindrical outer shape, of longitudinal axis parallel to each other, each brush being rotated by a shaft and being supported at each of its ends by a bearing forming part of a support which determines the spacing between the axes; longitudinals of said brushes, said support comprising at least two flexible branches oriented substantially perpendicular to said longitudinal axes, so that their respective ends constitute said bearings, said flexible branches being connected to a base adapted to ensure the attachment of said support on said body. To do this it is proposed according to a first aspect of the invention, that said at least one brush is formed of bristles oriented perpendicularly to the longitudinal axis of said at least one brush, said bristles having different lengths so forming at least one brush at least one region of reduced cross-section with respect to the substantially cylindrical cross section of said at least one brush at said at least one brush.

Such a modification of the generally cylindrical external shape of at least one of said component brushes of the apparatus according to the invention makes it possible to adapt the forces to the external profile of the dentition, which constitutes an interesting improvement, particularly in terms of gingivitis and other dental problems.

Improved brushing is obtained due to a non-constant contact between the bristles and the considered surface namely the tooth and / or the gum.

According to a first embodiment of the invention, said bristles together form a flat, preferably over the entire length of the at least one contra rotating brush. This embodiment makes it possible to exert a variable force on the teeth and the gums during the rotation of the brushes. This variation induces a massaging effect on the gums and teeth; it advantageously creates a drainage of the gums due to the movement created. According to another embodiment of the invention, said bristles together form a longitudinal sawtooth profile. This "interdental" profile is called because it allows the longer hairs to be easily in contact with the interdental zones, simultaneously with the other areas in contact with the brush or brushes and with the same support force. Without departing from the scope of the invention, said bristles together form a crenellated longitudinal profile. The slots are formed by two lengths of bristles that alternate along the length of at least one brush.

As an illustration, said bristles have a free length of between 0.5 cm and 2 cm. They can be made of a plastic material such as Tynex ®. According to one embodiment of the invention, the apparatus further comprises a retaining piece for locally bringing the axes of said rotary shafts. Specific brushing is here obtained.

More specifically, said retainer is disposed substantially in the middle of the length of the rotary shafts.

BRIEF DESCRIPTION OF THE FIGURES

Other features, details and advantages of the invention will become apparent on reading the description which follows, with reference to the appended figures, which illustrate: FIG. 1, a front view of an apparatus for brushing teeth according to a first embodiment of the invention;

Figure 2 is a bottom view of a toothbrushing apparatus according to a first embodiment of the invention;

Figure 3 is a perspective view of a brush according to the first embodiment of the invention;

4A, 4B and 4C, schematic sections of the relative positioning of a brush vis-à-vis a tooth;

Figure 5A is a perspective view of a brush according to a second embodiment of the invention;

Figure 5B is a sectional view of a brush according to a second embodiment of the invention;

Figure 6A is a perspective view of a brush according to a third embodiment of the invention;

Figure 6B is a longitudinal section of a brush according to the third embodiment of the invention; and

Figure 7 is a diagram of a brush according to another embodiment of the invention. For clarity, identical or similar elements are identified by identical reference signs throughout the figures.

DETAILED DESCRIPTION OF AN EMBODIMENT

Figure 1 thus illustrates a so-called front view of a toothbrushing apparatus according to a first embodiment of the invention. This view is complementary to Figure 2 which shows a bottom view of the same device. This apparatus comprises a body 10 on which is fixed a head 1 provided with counter-rotating brushes 2, 2 '. Preferably, two contra-rotating brushes are provided here; a larger number of brushes (for example three) could be envisaged without departing from the scope of the invention. Counter-rotating brushes 2, 2 'have a generally cylindrical outer shape; they are arranged so that their longitudinal axes X, X 'are parallel to each other and each coaxial with the axis of a drive shaft 4, 4'. Each brush 2, 2 'is supported at each longitudinal end by a bearing 3, 3', 5, 5 'forming part of a support 6.

A preferred embodiment of a support 6, as shown in Figures 1 and 2, comprises at least two flexible branches 6a, 6b; 6c, 6d oriented perpendicularly to the longitudinal axis X, X 'of the brushes; ends of the branches constitute the bearings 3, 3 ', 5, 5' of the rotating brushes. Moreover, the flexible branches are connected together to a base 6a which can for example allow the attachment of the support 6 to the body 10 of the brushing apparatus.

This is an embodiment of a support 6 counter-rotating brushes 2, 2 ', in particular to ensure a parallel positioning of the brushes and spacing between them. At least one brush 2, formed of radially oriented bristles that is to say perpendicular to the longitudinal axis X, X 'has a specific external shape, not entirely cylindrical. Such a brush has a reduced cross section vis-à-vis its overall shape and substantially cylindrical. Figure 3 shows the general shape of such a brush 2 which here has a flat 21 over its entire length. To do this, the bristles of the brush have different free lengths, a length R corresponding to the cylinder portion and a length R 'less than R which corresponds to the flat. Figures 4A, 4B and 4C show the application of the bristles of such a brush against the relevant face of a tooth 100, for two positions of the brush vis-à-vis the tooth. The first position corresponds to a further position in which the axis X, X 'of the brush passes through the center O of the cylindrical contour of the brush; this contour is symbolized by dotted lines in FIG. 4. The second position corresponds to a closer position in which the axis X, X 'of the brush passes through the center O' of the cylindrical contour of the brush; this contour is symbolized by mixed lines in FIGS.

In the first position only the bristles of greater length R are in contact with the tooth 100. During the rotation of the brush concerned, the teeth 100 and the associated gum are thus successively brushed and then not brushed (when the flat 23 is in front of the teeth).

When the brush is placed in the second position, the bristles permanently contact the teeth, with more or less force. This creates a differentiated brushing, more or less strong, which can be compared to a massage or to a drainage at the level of the gum. Using a brush according to the invention, a better brushing is achieved due to differentiated contact forces which are exerted on the surfaces of the teeth, throughout the rotation of the brushes.

More precisely: Calculation of resistance under a load P:

3

PL

formula: f =

3 El

f (mm): arrow under load

P (N): charge

L (mm): length of the embedded filament

σ (N / mm ² ) .100

E (N / mm ² ): Young's modulus E =

ε

G (N / mm ² ): elastic stress in flexion

£ (%): elongation in% IT D ⁴

I (mm): moment of inertia I = -

64

D (mm): diameter of the filament

The charge P varies according to the crushing of the brush f.3.E.I

The load P of the filament on the tooth therefore increases proportionally to the value of the arrow (f) due to the crushing of the brush.

Let's vary L:

f.3.E.I

P - nr-

The charge P of the filament on the tooth increases as a function of the decrease in length at the power 3.

Thus for a given profile of the same brush where the length of the filament varies (sawtooth profile, crenel or other) the action of the filament on the tooth allows depending on its length and its crushing. 'get a brush that goes from massage on the gum for longer filaments, to an effective brushing that removes plaque for the shortest.

Figures 5A and 5B illustrate a brush embodiment where the bristles together form a longitudinal sawtooth profile. Each tooth of the brush 2, or increment, is formed of a first face 22 inclined at a given angle, for example between 30 ° and 60 ° vis-à-vis the longitudinal axis XX '; Each tooth of the brush 2 has a second face 23 inclined at an angle of between 30 ° and 60 ° vis-à-vis the longitudinal axis XX '. Of course the angles of inclination are given here for illustrative purposes. This profile will be preferentially chosen when it comes to performing an interdental brushing, where the brush exerts a constant or almost constant force on the convex faces (curved and irregular) teeth. FIGS. 6A and 6B relate to an embodiment of a brush of general shape called crenel because formed of a succession of cylindrical zones 24 where the bristles all have a length R, and cylindrical zones 25 where the bristles all have a length R 'less than R. [0035] It is also conceivable without departing from the scope of the invention to provide longitudinal sectors of convex outer shape, arranged longitudinally and successively to form a rotating brush.

The invention relates to brushing apparatus where all the brushes have the same shape but it does not exclude embodiments where some only brushes have specific shapes.

Preferably two brushes 2, 2 'of the same shape and the same size are provided. This arrangement allows to treat in the same way the two halves of the mouth of the user. More precisely, the upper left vestibular vertical surface (cheek) is brushed by the same brush as the lower right outer face; similarly it is the same brush that acts on the inner faces of the teeth, respectively upper right and lower left.

Regarding the dimensions of the head and the hair, the latter commonly have a length of between 0.5 cm and 3 cm for uses in humans. The bristles are preferably made of a flexible plastic. Interestingly, the bristles can be made of Tynex ®, Nylon ® filament marketed by Dupont. The hairs can be externally smooth or rough. They can be hollow or full. They may advantageously contain capsules of medicinal or antibacterial products.

The diameter of the bristles can be between 7/100 ^th mm and more than 20/1000 ^th mm. The free ends of the bristles may be rounded, concave, bumpy or cut in a particular way, for example conical. A length commonly provided is of the order of 0.10 mm.

A type of hair will be chosen depending on the case: adult or child user; current or postoperative use; irritated gums or not ... Without departing from the scope of the invention, the bristles may consist of a rubber or a composite material having specific effects on the teeth or gums.

Other materials may of course be chosen by those skilled in the art without departing from the scope of the invention.

Furthermore, an additional retaining piece 7 may be provided and placed around the shafts or drive shafts 4, 4 'of each of the brushes. These axes being relatively flexible and thin, the part 7, preferably placed in the middle of the length of the axes 4, 4 ', allows to bring them locally so that the axes XX' of each brush define an angle A between them. This is to obtain a differentiated massage of the teeth between the distal portion and the proximal portion of each brush. The retaining piece has a form of double hook C, as visible on the cross section 7A. Any other technically equivalent form can be retained without departing from the invention.

Claims

Apparatus for brushing teeth with multiple rotating brushing systems, comprising a body on which is fixed a head (1) provided with counter-rotating brushes (2, 2 '), adjacent, of substantially cylindrical outer shape, of parallel longitudinal axis between them, each brush (2, 2 ') being rotated by a shaft (4, 4') and being supported at each of its ends by a bearing (3, 3 ', 5, 5') forming part of a support (6) which determines the spacing between the longitudinal axes of said brushes, said support (6) comprising at least two flexible branches (6a, 6b, 6c, 6d) oriented substantially perpendicular to said longitudinal axes, so that their ends respective constitute said bearings, said flexible branches being connected to a base (6 e) adapted to ensure the fixing of said support (6) on the head (1) characterized in that said at least one brush (2) is formed of oriented bristles perpendiculaireme nt to the longitudinal axis XX 'of said at least one brush, said bristles having different lengths so as to form at the level of said at least one brush at least one zone of reduced cross-section with respect to the cross-section substantially cylindrical of said at least one brush, and in that it further comprises a retaining piece for locally bringing the axes of said shafts (4,4 ') rotating.

Toothbrushing apparatus according to claim 1 characterized in that said bristles together form a flat (21), preferably over the entire length of the at least one contra-rotating brush.

Toothbrushing apparatus according to claim 1 characterized in that said bristles together form a longitudinal profile (22, 23) sawtooth.

Toothbrushing apparatus according to claim 1 characterized in that said bristles together form a crenellated longitudinal profile (24, 25). Toothbrushing apparatus according to any one of the preceding claims, characterized in that said bristles have a free length of between 0.5 cm and 2 cm. Toothbrushing apparatus according to any one of the preceding claims, characterized in that said bristles are made of a plastic material such as Tynex ®.

Apparatus according to any one of the preceding claims characterized in that said retaining piece is disposed substantially in the middle of the length of the rotating shafts (4, 4 ').