This invention relates to a toothbrush.

More in particular, this invention relates to a toothbrush provided with a mobile bristle-~holdi.no: head. BACKGROUND ART

Toothbrushes for dental care provi e with a fixe bristle-holdinq head aligned with the axis of the handle are known to the art and marketed.

It is also kwown that in order to clean the teeth thorouσh- ly, it is necessary to realize a movement of the bristles according to the axis of the teeth and that the toothbrush¬ es utilized today do not allow easily this movement, as it is perpendicular to the axis of the handle.

Various solutions have been proposed to overcome this drawback. For instance, a toothbrush has been prooosed whose head anqulation is variable and or -det rminable relatively to the axis of the handle.

A toothbrush of this type is disclosed in the Italian patent nr . 1.205.608, granted on March 23, 1989. In this toothbrush, the arranqement and stabilization of the handle according to various anqulations relatively to the bristle-holdinα head is obtained by means of rises inteαral with the handle, radially arra ged around a oint and opposinq radial recesses integral with either the head back or the internal wall of a tonαue substantially parallel to the back of said head and inteαral with same, or by means

of rises Integra] with the head which enαaαe into recesse ^s obtained in the handle. By this realization, variable and stabilized anoulations can be obtained- jn particular, anqulations of 22.5°, 45°, 90° and 180°.

The anqulation of the head relatively to the handle is chosen by hand-operatlnq on same until tne position is found which allows to exercise the maximum effort in the optimum direction for cleaning the teeth x. e alonα their longitudinal axis.

This condition can resoected as Jonα a= th ^~ inclination of the handle is kept constant durino the cleaning operation. In fact, minor variations m the hand oosit on suffice to change the inclination of the handle and therefore the position of the head relatively to an original oosition which has been considered as being the optimum one. This involves therefore continuous changes in th< ^~ - anαulation of said head. Besides, the hand-adηustment of the head in¬ volves rather delicate hyαiene considerations. DISCLOSURE OF INVENTION

O iect of this invention is to provide a toothbrush such a=. to allow to overcome the aforementioned drawbac s and limitations of toothbrushes provided with bristle- hold.) no heads whose angulation is variable and i-redeter nabJ e According to this invention, this and further ob .ecf which will be clarified bv the following descrioti n ar< ^~ - achieved by a toothbrush comprising a handle, a brl tle-holdin heao and means for engaging the head into an end of the handle,

wherein the bristle-holding head can rotate frεelv. both clock- and counterclockwise, oscillating at the same time on the axis of said engaαement means, said axis hemo perpendicular to the handle.

- The free rotatory movement of the head allows th^ same to arrange automatically in the optimum position relatively to the axis of the teeth in any point of the dental arch, independently on any change in the inclination of the hand or the handle, achieving therefore a very efficacious and rapid cleaning action.

- The oscillatory movement of the head allows to obtain an easier and more efficacious touch between bristles and teeth in the internal part of the dental arch, and in particular in the part concerned bv upper and lower pre o- lars and molars.

BRIEF DESCRIPTION OF DRAWINGS

The characteristics of the** toothbrush subiect matter of this invention will be evident from the followinα detailed description, wherein reference i made to the attached drawings which represent some preferred, non limitative embodiments, illustrated by way of example, wherein:

Fig. 1 is a schematic side view of the toothbrush subηect matter of this invent on, with the top end of the handle assembled to the rotating and oscillating bristle- holdlno head;

Fig. 2 is a schematic side i^w of the too ends of the non assembled handle and br istle-holdinq heads:

Fiq. 3 is a schematic front view, in correspondence of the bristle side, of the toothbrush subiect matter of this invention ;

Fig. 4 is a schematic front view of the upper part of the handle;

Fig. 5 is a aαnified detail of the too end . A . of the handle of Fiq. 2;

Fiq. 6 s a magnified detail cf the Pιiαaαer.-nt ^ans (A') of the bristle-holdinq head of Fiq. 2;

Fiq. 7 is a maqnified detail of the enαaα<~-merιt means (B) opposite to the enqaqement pin (B) of Fiq. 1;

Fig. 8 is a schematic view of the side opposite to the bristle site (C of Fiq. 6) of the enqaqement pin of the rotating and oscillatmq head;

Fiq. 9 is a schematic view of the section of the upper part of the handle along a plane passinσ throuoi. the X-X line of Fig. 4; and

Figs. 10 through 13 are details of a variant of the engagement means of the bristle-head rotating and oscillat¬ ing on the top end of the handle.

Figs. 1 throuqh 9 show a preferred embodiment of the tooth¬ brush provided with a rotatmq and oscillating head, sub¬ iect matter of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Such toothbrush comprises a handle, preferably from *-ιqιd plastic material, provided with a top end ( 2 ) and a bris-

SUBST1TUTESHEET(RULE26)

tle-holdmα head (4.. Said head (4) comprises a back .5. preferably from semirigid and sliσhtlv elastic plastic material, in which bristles (3. are inserted. Gaid Pact- ⁽ 5 is provided, on the opposite side relativel ^y to bristles (3) and in a position balanced and integral with said back, with a pxn (8) provided with longitudinal strips (9.. Gaid pin (8) provided with said strips (9) is mushroom-shaped. The assembly of said head (4) with the handle too end (2) is achieved bv engaging said pin .8^ into a recess (6) obtained on the surface (12) of said too end (2. orientated towards said head and realized durinc the mouldino staαe of the part. Gaid recess (6. comprises a lead-in round hole (11) whose diameter is smaller than the maximum diameter of pin (8). When pin (8) is pushed into hole (11). strips (9) bend radially ")ust enough to allow said pin to αet into said recess (6.. Once pm (8 > has αot into recess (6), strips (9) resume their startmα arrangement and base (13. of pin (8) draws up against edge (7) of recess (6), pre¬ venting the bristle-holding head (4. from unhooking. The clockwise (FI) or counterclockwise (F2. free rotation is achieved by allowing a small clearance (0.2 - 0.5 mm. between the surface of recess (6) and the peripheral sur¬ face of strips (9).

Surface (12. of the handle top end (2) s not uniformly parallel to the correspondinα surface of back c 5^> . beinα tapered both longitudinally above and under hole .11 ^ ano transversally at both sides of hole (11.. Guch taoeπnαs,

together with an angulation between base (13. of pm (S. and edge (7) of recess (6), allow head (4. to oscillate freely on the rotation axis, with anoulations <y between said surface (12) and the correspondiriq surface of said back (5. and said base (13) of pin (3 ) and sai edαe (7. as shown on Fiαs. 1, 7 and 9. The optimum amplitude of angulations ot is 2° - 5° .

Figr. 10 through 13 show a variant of the svstem of assem¬ bly of the bristle-holding head to the handle top end ot the toothbrush subηect matter of this invention. Back (5) of the bristle-holdinq head (5., preferably from semirigid and slightly elastic material, as specified above, com¬ prises, in a balanced position, a gudgeon pm (18) provid¬ ed, alonq the perimeter, with a rise (17) havinq a tπanqu- lar transversal section, as shown on Fig. 12. The handle top end (2), preferably from rigid plastic material, as specified above, comprises a hole (21) and a recess (19., as shown on Fiq. 11. A hollow oounter-qudαe>on p (16) is provided separately, whose αeometrιcal struc¬ ture allows to house in the inside, with a suitable clear¬ ance, said qudqeon pin (18.. Counter-αudαeon pm ci6. is provided, alonq its internal surface and the perimeter, with stop peqs (15) havinq a trianqular rectanqle transver¬ sal section, as shown on Fig. 10. Said hollow counter- qudqeon pin (16) is suitably made from riqid plastic mate¬ rial , ηust as the handle. The assembly of head (5) on the handle top end (12. is

obtained by introducing, in the direction of arrow Fό. gudgeon pin (18) into hole (21). and introducing then in the opposite direction according to arrow F5. counter- qudqeon pin (16) into recess (19). In so doinα. αudαeon pin (18) gets into the recess of said hollow counter-αudαεon pin (16), as shown on Fiq. 13. The lockinq between qudgeon pin (18) and counter-gudgeon pin (16) is obtained bv the clutching of said rise (17) on peqs (15). The rotatory movement of the head is ensured by leavinq, also in this case, a clearance of 0.2 - 0.5 mm between the external surface of the counter-αudαeon pin (16. and the surface of the hole (21) and between the internal surface (14') of head (14) of said counter-oudαeon pin (16) and the surface (20) of said recess (19). The oscillatory movement of the head is allowed, instead, by the anαulations o. of 2° - 5° provided between said surface (14') and said surface (20), and, .-just as in the above described solution, between the taperinos of surface (12) of handle top end (2. and the correspondinq surface of back (5) of the bristle-holdino head.

The described toothbrush may be realized in different sizes and in particular in the sizes suitablεs for αrown-ups and children. All the corners and tips of the head and the handle are suitably rounded off and. besides, the head protrudes relatively to the handle top.

While the invention has been described with reference to some preferred embodiments, it is evident that many van-

ants and chanqes may be made by those expert, of the art, in the light of the above disclosure. Therefore, this inven¬ tion includes all of the alternatives and chanqes that fall within the spirit and the protection scope of the following claims.