Technical sector

The present invention is generally in the sector of oral hygiene devices; in particular, the invention refers to an electric toothbrush.

Prior art

The correct brushing action taught by dentists states that the lower teeth must always be brushed from the bottom to the top and the upper teeth from the top to the bottom, and the tooth plane, i.e. the chewing surface of the tooth, must be brushed transversely.

Electric toothbrushes made using the prior art usually have rotating heads that rotate alternately along two opposite rotation directions. Disadvantageously, since the rotation is not controlled according to any rule but is simply alternated in two possible directions, the current electric toothbrushes may be found to be in the condition of not performing the correct brushing action taught by dentists described above.

The action of the current electric toothbrushes thus does not satisfy the requirements for proper interdental cleaning and gingival massage, as required by dentists.

Currently, a correct brushing action may only be achieved by means of manual toothbrushes. Disadvantageously, the action of manual toothbrushes may ensure that only a moderate degree of dental hygiene is achieved with a considerable amount of time.

JPS5523199U describes an electric toothbrush for cleaning teeth with a rotating brush. However, the aforesaid problems remain unresolved.

Summary of the invention One of the aims of the present invention is therefore to provide an electric toothbrush that can replace the correct use of the manual toothbrush, ensuring proper interdental cleaning and ensuring proper gingival massage as required by dentists.

The aforesaid and other objects and advantages are achieved, according to an aspect of the invention, by an electric toothbrush having the features defined in claim 1. Preferred embodiments of the invention are defined in the dependent claims, the content of which is intended as an integral part of the present description.

Brief description of the drawings

The functional and structural features of some preferred embodiments of an electric toothbrush according to the invention will now be described. Reference is made to the accompanying drawings, wherein:

- Figure 1 illustrates a first embodiment of an electric toothbrush according to the present invention;

- Figure 2 illustrates the electric toothbrush in Figure 1 , wherein the head of the electric toothbrush is made to flex, for example, according to a flexion direction, and presses the push switch located at the top in the figure;

- Figure 3 shows an electric toothbrush wherein the head of the electric toothbrush is made to flex, for example, according to a flexion direction, and presses the push switch located at the bottom in the figure;

- Figure 4 is a side view of the electric toothbrush in Figure 1 ;

- Figure 5 illustrates a second embodiment of the electric toothbrush; and

- Figure 6 illustrates an exemplifying circuit diagram that may be used within the electric toothbrush.

Detailed description

Before explaining in detail a plurality of embodiments of the invention, it should be clarified that the invention is not limited in its application to the constructive details and to the configuration of the components presented in the following description or illustrated in the drawings. The invention may assume other embodiments and may in practice be implemented or achieved in different ways. It should also be understood that the phraseology and terminology have descriptive purposes and should not be construed as restrictive. The use of "include” and“comprise” and the variations thereof are to be understood as encompassing the elements stated hereinafter and the equivalents thereof, as well as additional elements and the equivalents thereof.

Initially making reference to Figure 1 , a first embodiment of an electric toothbrush according to the present invention is illustrated.

This electric toothbrush I is a toothbrush for cleaning the teeth that comprises a main body 10 and a head 2.

The head 2 comprises a stem 4 and a rotating element 6, arranged at one end of said stem 4.

The rotating element 6 includes a plurality of bristles 8 and is adapted to rotate according to two opposite rotation directions, in particular a first rotation direction r l and a second rotation direction r2 opposite to said first rotation direction rl .

The head 2 is connected to said main body 10 in an articulated manner.

The electric toothbrush 1 further comprises a transmission shaft 12, at least partially housed in the stem 4 of the head 2. The transmission shaft 12 is provided to rotate the rotating element 6 of the head 2.

The rotating element 6 may rotate around a rotation axis perpendicular to an axis of the transmission shaft 12.

Moreover, the electric toothbrush 1 includes a motor 14 powered by a power supply means 16 and adapted to generate a rotary motion to be transmitted via the transmission shaft 12 to the rotating element 6 of the head 2 so as to generate a rotation of said rotating element 6 according to the first rotation direction rl and the second rotation direction r2. This motor 14 and the power supply means 16 are arranged within the main body 10.

The electric toothbrush I , as may be seen in figure 1 , comprises a first push switch 18A provided to detect a relative inclination of the head 2 relative to the main body 10 according to a first flexion direction fl . This first push switch 18A is arranged around the transmission shaft 12 in such a way that the first push switch I 8A is pressed by the transmission shaft 12 when the latter is inclined relative to the main body 10 according to the first flexion direction fl . Pressing the first push switch 18A causes a rotation of the rotating element 6 of the head 2 according to the first rotation direction rl via the motor 14.

The electric toothbrush 1 comprises moreover a second push switch 18B provided to detect a relative inclination of the head 2 with respect to the main body 10 according to a second flexion direction f2, opposite to said first flexion direction fl . The second push switch I 8B is arranged around the transmission shaft 12 in such a way that the second push switch I 8B is pressed by the transmission shaft 12 when the latter is inclined with respect to the main body 10 according to the second flexion direction f2. Pressing the second push switch I 8B causes a rotation of the rotating element 6 of the head 2 according to the second rotation direction r2 via the motor 14.

Still further, as seen in Figure 4, the electric toothbrush 1 also comprises a third push switch 18C provided to detect a relative inclination of the head 2 with respect to the main body 10 according to a third flexion direction f3. The third flexion direction f3 is substantially perpendicular to said first flexion direction fl and said second flexion direction f2. The third push switch 18C is arranged around the transmission shaft 12 in such a way that the third push switch 18C is pressed by the transmission shaft 12 when the latter is inclined with respect to the main body 10 according to the third flexion direction f3. Pressing the third push switch 18C causes a rotation of the rotating element 6 of the head 2 according to the first rotation direction rl or the second rotation direction r2, via the motor 14. In this case, it is not important if the rotating element rotates according to the first or second rotation direction rl , r2, since this condition is provided for cleaning the chewing plane of the teeth.

The third push switch 18C may be placed on a side of the transmission shaft 12 facing the third flexion direction f3 or a direction opposite to the third flexion direction f3.

With reference to figure 2, in one embodiment, the first push switch 18A may be placed on a side of the transmission shaft 12 facing the first flexion direction fl and the second push switch 18B may be placed on a side of the transmission shaft 12 facing the second flexion direction f2. According to this arrangement, when the head 2 is flexed upwards, the second push switch 18B will be pressed, and vice versa.

In this case, the pressure of the switches depends on the pivot point.

Otherwise, with reference to figure 3, in a further embodiment, the first push switch I 8A may be placed on a side of the transmission shaft 12 facing the second flexion direction f2 and the second push switch 18B may be placed on a side of the transmission shaft 12 facing the first flexion direction fl . According to this arrangement, when the head 2 is flexed upwards, the first push switch 18A will be pressed, and vice versa.

For example, the push switches may be standard switches, push-button switches or micro- switches.

Still by way of example, as may be observed from figures 1 -3, the rotating element 6 may be a cylindrical brush with bristles orthogonal to the axis z. In other words, the rotating element may have a roller shape. With reference to figure 4, on the other hand, the rotating element 6 may have a circular structure with bristles emerging from only one of the surfaces of the said circular structure.

Still referring to the figures, the main body 10 may comprise an elongated section 13 and a dome section 15. The dome section 15 may have an opening for the passage of the transmission shaft 12. Within the dome section 15 there may be placed said push switches I 8A, 18B, 18C. The elongated section 13 and the dome section 15 may be made in one piece or made separately and subsequently assembled together. In addition, the elongated section 13 and the dome section 15 may be made by molding a plastic material or by forming a metal material, such as aluminum. For example, the elongated section may be cylindrical or polygonal in shape or any shape that may facilitate the grip by a user.

Making a practical example of use of the electric toothbrush 1 , the latter may begin its action as soon as it is positioned, for example, in the left outer part of the lower dental arch, and, to avoid splashes, the lips are half-closed. At that moment, the slight upward flexion of the stem will activate the second push switch 18B, which will signal to the motor 14 to rotate the rotating element 6 counterclockwise, i.e., the rotating element 6 will brush the teeth and gums from bottom to top. Continuing the action and moving the electric toothbrush onto the chewing plane of the teeth, the third push switch 18C dedicated to this position will be activated, rotating the rotating element in one of the two possible directions rl or r2.

Rotating again another 90°, the toothbrush finds itself in the inner left part of the lower dental arch. At that moment, the slight flexion of the stem, opposite to the flexion detected when the toothbrush is in the outer left part of the lower dental arch, will activate the second push switch 18B, which will signal to the motor 14 to rotate the rotating element 6 clockwise. In this way, the brushing will again be from the bottom to the top. The operation, which will be repeated in the four portions of the teeth, will thus find the appliance in any case with the correct rotation direction, in order to always brush the teeth from the bottom to the top.

As illustrated for example in Figure 3, the electric toothbrush 1 may comprise a plurality of inclination switches 20 provided to detect a rotation of the electric toothbrush 1 , from a first predetermined position to a second predetermined position, around a longitudinal axis z of the electric toothbrush 1 . In the present description and in the claims, the term and the expressions indicating '‘longitudinal ^" positions and orientations shall be understood as substantially parallel to the direction of the axis of the transmission shaft 12. Moreover, the term and the expressions indicating“transverse” positions and orientations shall be understood as substantially perpendicular to the direction of the axis of rotation of the rotating element 6.

The second predetermined position is rotated substantially +90° or -90° with respect to the first predetermined position.

When the electric toothbrush I is determined to be in the first predetermined position, even if the third push switch 18C is pressed by the stem 4 of the head 2, the latter cannot cause a rotation of the rotating element 6 via the motor 14. Only pressing the first push switch 18A or the second push switch 18B may cause a rotation of the rotating element 6 via said motor 14.

When, on the other hand, the electric toothbrush 1 is determined to be in the second predetermined position, even if the first push switch 18A and/or the second push switch 1 8B is/are pressed, they cannot cause a rotation of the rotating element 6 via the motor 14. Only pressing the third push switch 18C may cause a rotation of the rotating element 6 via said motor 14.

For example, referring to Figures I and 3, Figure 1 illustrates the electric toothbrush in the first predetermined position, and Figure 3 illustrates the toothbrush in the second predetermined position.

The first predetermined position is provided for cleaning the side walls of the teeth, whereby a flexion of the head 2, and consequently of the transmission shaft 12, according to the third flexion direction f3 is not only not necessary, but must also be excluded from detection as it could lead the motor to be controlled in a contrasting manner if a flexion according to the third flexion direction f3 is also detected. For this reason, the push switch I 8C provided to detect a flexion according to the third flexion direction f3 is disabled and is not used to detect a possible flexion. Conversely, the second predetermined position is provided for cleaning the chewing plane of the teeth, whereby flexions of the head 2, and consequently of the transmission shaft 12, according to the first or second flexion direction are not only unnecessary, but must also be excluded from detection as they could lead the motor to be controlled in a contrasting manner if a flexion according to the first and second flexion direction is also detected. For this reason, the push switches 18A, 18B provided to detect flexion according the first or second flexion direction are disabled and are not used to detect a possible flexion.

The following solution may be used to disable these switches.

The electric toothbrush I may comprise a first relay to disconnect the first push switch I 8A from the motor 14 and a second relay to disconnect the second push switch I 8B from the motor 14.

The first push switch 18A and the second push switch 18B are disconnected from the motor 14 by means of said first relay and second relay when the electric toothbrush 1 is detected to be in said second position by the inclination switches 20, so that the first push switch 1 8A and the second push switch 18B cannot cause the rotation of the rotating element 6.

The electric toothbrush 1 may further comprise a third relay adapted to disconnect the third push switch 18C from the motor 14.

The third push switch 18C is disconnected from the motor 14 when the electric toothbrush 1 is detected to be in said first position by the inclination switches 20, so that the third push switch 18C cannot cause the rotation of the rotating element 6 via the motor 14.

Referring to figure 3, the electric toothbrush may further comprise an oscillating support 21 whereon is mounted the plurality of inclination switches 20. The oscillating support 21 may be a simple circuit board hinged at one end to the main body 10.

The oscillating support is adapted to allow the correct functioning of the inclination switches 20 even when the electric toothbrush is inclined with respect to a transverse axis y perpendicular to said longitudinal axis z.

This situation may occur when a user bends over a washbasin while brushing his/her teeth.

This oscillating support 21 allows for this inclination to be compensated and ensures the correct operation of the inclination switches 20.

In an alternative embodiment not illustrated in the figures, the push switches 18A, 18B, I 8C, instead of being housed in the main body 10 of the toothbrush 1 , are arranged within the stem 4 of the head 2, around the transmission shaft 12. In this case, the stem is made of flexible material. The flexion of the same stem will press one of the push switches in the event of a flexion thereof.

In any one of the preceding embodiments, the head 2 may be removably coupled to the main body 10, and/or the rotating element 6 may be removably coupled to the stem 4 of the head 2.

Preferably, the periodic replacement of the rotated element 6 alone is a more economical solution and does not compromise the articulated part between the main body 10 and the head 2. The articulated part is a point that requires a very precise coupling to guarantee the flexibility required for the stem of the head and, at the same time, the watertightness of the main body 10.

Moreover, the power supply means 16 may be one or more classic replaceable batteries or a rechargeable battery. Still further, the electric toothbrush may comprise an annular gasket, or a bellows, arranged at the point of connection of the head 2 with the main body 10. Such an annular gasket, or bellows, is adapted to allow the flexion of the head 2 with respect to the main body 10 and to guarantee the water seal of the main body 10.

The annular gasket may be, for example, an O-ring.

The advantage granted by the present invention is thus to provide an electric toothbrush that may replace the correct use of a manual toothbrush, ensuring proper interdental cleaning and ensuring proper gingival massage as required by dentists.

Moreover, due to the rotation speed of the rotating element of the electric toothbrush, the number of bristles passing through the teeth and gums is several times higher than that achievable using a normal manual toothbrush. This results in an intense gingival massage, with guide to cover the neck of the tooth, which is a very useful action in the treatment of “pyorrhea" and a better use of the properties of the toothpaste used, cleaning the teeth more thoroughly. In addition, there will be an action very similar to that carried out by interdental floss because the improved brushing capacity of the inner part and the chewing plane allows the use thereof to be reduced, if not eliminated, with significant time savings.

Various aspects and embodiments of an electric toothbrush according to the invention have been described. It is understood that each embodiment may be combined with any other embodiment. The invention, moreover, is not limited to the described embodiments, but may vary within the scope defined by the accompanying claims.