WO2006109077A9

WO2006109077A9 - Toothbrush with a vibrating head part

Info

Publication number: WO2006109077A9
Application number: PCT/GB2006/001364
Authority: WO
Inventors: Nicos Raftis
Original assignee: Wisdom Toothbrushes Limited
Priority date: 2005-04-13
Filing date: 2006-04-13
Publication date: 2010-01-28
Also published as: EP1871280A1; CN101715328A; GB2425050A; WO2006109077A1; NO20075822L; GB0507480D0

Abstract

The present invention relates to a toothbrush having a head utilising a vibrating device for the generation of motion contained within the head and fixed directly on the top part of the head having bristles, the top part of the head with the electromechanical device being connected to a lower part or a side part of the head through a flexible part, and the lower part or side part of the head being connected to the neck and handle such that the energy of vibration is focused on the top part which can move relative to the neck part with only minimal vibration being transmitted to the toothbrush handle. The invention provides a toothbrush head whereby the entire mechanism for motion generation is contained within the head with all energy of the motion generating device being concentrated on the tufted part of the head, while the size of the toothbrush can correspond roughly to the size of manual toothbrushes and flexibility is provided for the design of the neck and handle.

Description

TOOTHBRUSH WITH A VIBRATING HEAD PART

[001] FIELD OF THE INVENTION

[002] This invention relates to a toothbrush having an electromechanical device for the generation of motion contained within the head and fixed directly on the tufted part of the head having bristles, the tufted part of the head with the electromechanical device being connected to a lower part of the head through a soft material, and the lower part of the head being connected to the neck and handle.

[003] BACKGROUND OF THE INVENTION

[004] A wide variety of power toothbrushes, using various driving mechanisms, are well known. Power toothbrushes generally provide better cleaning action than manual toothbrushes and are often preferred by consumers . Most power toothbrushes use a motor or actuator to generate motion, and then transmit the motion to a tufted head through various types of shafts and drive mechanisms. Such motion is often continuous rotary, oscillatory rotary, or linear back-and- forth or linear sideways. Other arrangements utilise magnetic drivers to generate motion that is also transmitted to the tufted head through various types of shafts and drive mechanisms. Various bristle arrangements on the head are known such as a single circular oscillating tufted disc, a combination of both stationary and moving tufted parts, or a combination of two or more moving tufted parts.

[005] These toothbrushes generally have a bulky body and head, and the head thickness tends to be significantly bigger than manual toothbrushes, making it difficult for the bristles to reach the back teeth. These toothbrushes also tend to be very noisy due to inefficient drive mechanisms .

[006] Another type of power toothbrushes utilise a vibrating device. Reference is made for example to U.S. Pat. Application Publication No. 2002/0124333 which relates to a toothbrush with a handle and a bristle- carrying head part which are interlinked by means of a neck part, and where the head part or the zone adjoining said head part accommodate a mechanical vibratory device that sets the head part vibrating. Vibration damping means are provided on the neck to reduce their transmission to the handle so that the toothbrush is pleasant to use.

[007] Although the size of these toothbrushes is close to the size of manual toothbrushes, the effectiveness of such toothbrushes is very poor because the energy of the vibrating device is dissipated on the entire head and neck rather than being focused on the tufted part and therefore cleaning action is not as effective. Despite the means of damping incorporated on the neck, the vibration is also transmitted to the handle making the use of such toothbrushes rather uncomfortable. Most of the energy of vibration is used unproductively, dissipated on the head and neck as well as on the damping part between the neck and handle, and on the handle itself.

[008] SUMMARY OF THE INVENTION

[009] The present invention provides a toothbrush comprising a head connected to a handle; a top part of the head having bristles; a lower part or a side part of the head connected to the handle; a vibrating device for vibrating the bristles located in the head and fixed to the top part of the head; wherein the top part of the head is connected to the lower part or side part of the head by a flexible part, such that the transmission of vibrations from the top part of the head to the lower part or side part of the head is reduced .

It is an object of the present invention to provide a toothbrush head having an electromechanical device for the generation of motion contained within the head and fixed directly on the tufted part of the head having bristles, and which in size corresponds roughly to the size of manual toothbrushes.

[010] A further object of this invention is to provide such a toothbrush whereby the head is split in at least two parts with the tufted upper part as fixed with the electromechanical device being connected to a lower part of the head through a soft material, and the lower part of the head being connected to the neck and handle, such that the electromechanical device produces maximum amplitude of motion, relative to the lower part, in the most efficient way.

[011] Still another objective of the present invention is to provide a means of easy electrical connection between the electromechanical device on the head and the power source that is stored in the handle of the toothbrush.

[012] The present invention provides several advantages over conventional power toothbrushes or other vibrating toothbrushes. In particular, the vibration is concentrated on the tufted part of the head thus providing maximum efficiency with regards to cleaning action. Only minimal vibration is transmitted to the handle, making its use very comfortable. Furthermore, the size of the toothbrush is comparable to manual toothbrushes, and is shaped in a way that makes it easy to reach the back teeth in the mouth. Another advantage is that the level of noise generated during operation is much lower than conventional power toothbrushes .

[013] BRIEF DESCRIPTION OF THE DRAWINGS

[014] This invention is described hereinbelow, by way of example, with reference to the drawings, in which: Figure 1 shows a perspective view of the toothbrush of the present invention.

[015] FIGS Al- A6 show one preferred embodiment of the invention whereby the vibrating electromechanical device is a round coin-type vibration motor which is mounted on the tufted top part of the head, and the bottom part of the head and the neck part are a single plastic moulding, whereby top and bottom parts of the head are separated by a soft material, preferably an elastomer.

[016] FIGS B1-B7 show another preferred embodiment of the invention whereby the vibrating electromechanical device is a round coin-type vibration motor which is mounted on the tufted top part of the head, and the bottom part of the head is formed out of a thin metal plate which is connected to the plastic neck part and whereby the top tufted part of the head and the bottom part of the head are separated by a soft material, preferably an elastomer.

[017] FIGS Cl-CIl show another preferred embodiment of the invention whereby the vibrating electromechanical device is a round coin-type vibration motor which is mounted on the tufted top part of the head, and the bottom part of the head is formed by a thin hollow metal plate which provides structural rigidity and which is completely encapsulated by a soft material, preferably an elastomer. [018] FIGS D1-D6 show another preferred embodiment of the invention whereby the vibrating electromechanical device is a tubular vibration motor with an eccentric mass, which is mounted on the tufted top part of the head, and the bottom part of the head is formed by a thin hollow metal plate which provides structural rigidity and which is completely encapsulated by a soft material, preferably an elastomer.

[019] FIGS E1-E13 show another preferred embodiment of the invention whereby the vibrating electromechanical device is a tubular vibration motor with an eccentric mass, which is mounted on the tufted top part of the head, the foresaid tufted top part having an arrowhead shape, and the bottom part of the head is formed by two thin vertical spring steel plates on either side of the vertical wall o£ the top part of the head, whereby the spring steel plates provide structural rigidity on the vertical plane while at the same time facilitating vibration on the horizontal plane, and which spring steel plates are completely encapsulated by a soft material, preferably an elastomer.

[020] FIGURES Fl and F2 show another preferred embodiment of the invention whereby the vibrating electromechanical device is a tubular vibration motor with an eccentric mass, which is mounted on the tufted top part of the head, and the fixed part of the head that is connected to the neck part, is in the form of a "fork", whereby the tufted part is secured in the middle space of the "fork" through a soft material, preferably an elastomer. [021] FIGS G1-G5 show another preferred embodiment of the invention whereby the vibrating electromechanical device is either a round coin-type vibration motor or a tubular vibration motor with an eccentric mass, which is mounted on the tufted top part of the head whereby the bristles pass through the top plastic plate and are fused on the bottom part of the head which is formed out of a thin metal plate. Water insulation is being provided by a thin elastomer layer.

[024] FIG H1-H6 show configurations of vertical spring steel plates and horizontal metal support plates in ways that contribute to further reduce transmission of vibration to the neck and main body of the toothbrush. [025] FIG Kl shows the electrical schema for driving the vibrating device;

[026] FIG K2 shows different possible signals for driving the vibrating device.

[027] The figures are presented and numbered as series. Therefore for example Figures A1-A6 represent six drawings all referring to a specific preferred embodiment, which is preferred embodiment A. The parts in each series of figures are numbered in a consistent way so that the same numbers represent the same generic part . So for example parts 2a, 2b, 2c, 2d, 2e, 2f, 2h all represent the bristles on the tufted top parts Ia-Ih respectively for each preferred embodiment. A generic reference to parti for example refers to each of parts Ia-Ih in each preferred embodiment.

[028] DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[029] The toothbrush heads illustrated in Figures series A to H each are split in at least two parts with the top part (1) being the tufted part containing bristles (2), and the bottom part (4) or side part (26e) being the part which provides structural support. The vibrating device

(7, 20) is always fixed on the top part. The top part (1) and the bottom part (4) or the top part (1) and the side part (26e) are connected between them by means of a flexible part (3) that allows relative movement between the top part (1) and the bottom part (4) or the top part

(1) and side part (26e) . [030] Each preferred embodiment will now be described in detail with reference to each series of figures.

[031] One preferred embodiment is illustrated in Figure 1 and figures A1-A6 and is described hereinbelow. Figure 1 shows the toothbrush comprises an elongate handle 40 which is suitable for being gripped by a user. The handle 40 is fastened to a head 41 by means of a neck 6. Figures Al and A2 show two isometric views which illustrate the sandwich structure of the toothbrush head whereby there is a top part (Ia) being the tufted part containing bristles (2a) , and a bottom part (4a) being the part which provides structural support, the abovementioned parts being separated by a flexible part (3a) . The bottom part (4a) is an extension of the neck part (Sa) that connects the toothbrush head to the handle (40) of the toothbrush .

[032] The top and bottom parts are made out of a hard material preferably plastic. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (Ia) at different angles and with different methods. The flexible part (3a) may be made of an elastomer. The flexible part (3a) may be formed through an overmoulding process whereby the elastomer is injection-moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould. " Alternatively the bonding may be formed by use of adhesives at the interfaces of the sandwich structure between the flexible part (3a) and the top part (Ia) and between the flexible part (3a) and the bottom part (4a) .

[033] The vibrating device (7) can be a coin-type vibrating motor or any other type of cylindrical shaped vibrating device. A recess (5a) on the bottom part (4a) can be created to help reduce the overall thickness at the tip of the had, that is, at the side of the head opposite to the neck part (6a) , create a perception of an lower overall thickness and give the visual effect of an "engine compartment" . Figure A3 shows a side view of the toothbrush head illustrating the forementioned effect on the head thickness. The recess (5a) is sufficient to create a clearance (8a) of at least lmm between the vibrating device (7) and the bottom part (4a) . Figure A4 shows in dotted lines the positioning of the vibrating device (7) and the clearance (8a) between the vibrating device and the bottom recess (5a) . Figure A5 shows a cutout view illustrating the forementioned sandwich structure .

[034] The vibrating device (7) can be attached to the top part (Ia) by use of adhesives or as an interference fit into a top part recess (9) . In any case, the forementioned top part recess (9) can function as a guide in positioning and attaching at the right position the vibrating device (7) onto the top part (Ia) . The vibrating device is powered from an electrical source through wires (10) which pass through a channel (not illustrated) which passes through the flexible part (3a) and through the neck part (6a) .

[035] When the flexible part (3a) is to be bonded to the top and bottom parts by use of adhesives, the flexible part can be formed in a way that a middle hole (lla) can be formed such that it has a diameter bigger than the diameter of the vibrating device (7) so that a clearance is formed between the vibrating device and the flexible part . [036] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Ia) and bristles (2a) thus producing an effective cleaning action. The flexible part (3a) also acts as a means of reducing the amount of vibration transmitted to the neck part (6a) and handle (40) of the toothbrush.

[037] Another preferred embodiment is illustrated in figures B1-B7 and is described hereinbelow. Figure Bl shows an isometric view which illustrate the sandwich structure of the toothbrush head whereby there is a top part (Ib) being the tufted part containing bristles (2b) , and a bottom part (4b) being the part which provides structural support, the abovementioned parts being separated by a flexible part (3b) . The bottom part (4b) is made out of thin metal plate and is connected to the neck part (6b) through its tail (4bT) which slides into a horizontal slot (13b) in the neck part that connects the toothbrush head to the handle (40) of the toothbrush. Figure B5 shows an exploded view of all parts . As shown in cut-out diagram in Figure B6 , the tail (4bT) of the bottom part (4b) is bent so that the slot (13b) is approximately in the middle plane of the neck part (6b) so as there is sufficient material on the neck part (6b) above and below the tail (4bT) for structural strength.

[038] The top part is made out of a hard material preferably plastic. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (Ib) at different angles and with different methods. The flexible part (3a) may be made of an elastomer. The flexible part (3b) may be formed through an overmoulding process whereby the elastomer is injection-moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould. Alternatively the bonding may be formed by use of adhesives at the interfaces of the sandwich structure between the flexible part (3b) and the top part (Ib) and between the flexible part (3b) and the bottom part (4b) . The tail (4bT) of the bottom part (4b) is secured into the slot (13b) of the neck part (13b) either by use of adhesives, or by an interference fit. Another way that the tail (4bT) of the bottom part can be secured into the neck part (6b) is to have an enlarged slot (30) as shown in Figure H2 so that the material of the flexible part (3b) can flow into the enlarged slot (30) during the injection moulding process. This feature is described in more detail later in this text .

[039] The vibrating device (7) can be a coin-type vibrating motor or any other type of cylindrical shaped vibrating device. A recess (5b) on the bottom part (4b) can be created to help reduce the overall thickness at the tip of the had, that is, at the side of the head opposite to the neck part (6b) , create a perception of an lower overall thickness and give the visual effect of an "engine compartment" . Figure B2 shows a side view of the toothbrush head illustrating the forementioned effect on the head thickness. The recess (5b) is sufficient to create a clearance (8b) of at least lmm between the vibrating device (7) and the bottom part (4b) . Figure B3 shows in dotted lines the positioning of the vibrating device (7) and the clearance (8a) between the vibrating device and the bottom recess (5b) Figure B6 shows a cutout view illustrating the forementioned sandwich structure .

[040] Figure B7 shows stamped ribs (4bR) as an optional structural feature on the bottom part (4b) that provides additional bending strength to the thin metal plate. [041] The vibrating device (7) can be attached to the top part (Ia) by use of adhesives or as an interference fit into a top part recess (9) . In any case, the forementioned top part recess (9) can function as a guide in positioning and attaching at the right position the vibrating device (7) onto the top part (Ib) . The vibrating device is powered from an electrical source through wires (10) which pass through a channel (12b) which passes through the flexible part (3b) and through the neck part (6b) .

[042] When the flexible part (3b) is to be bonded to the top and bottom parts by use of adhesives, the flexible part can be formed in a way that a middle hole (lib) can be formed such that it has a diameter bigger than the diameter of the vibrating device (7) so that a clearance is formed between the vibrating device and the flexible part .

[043] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Ib) and bristles

(2b) thus producing an effective cleaning action. The flexible part (3b) also acts as a means of reducing the amount of vibration transmitted to the neck part (6b) and handle (40) of the toothbrush.

[044] Yet another preferred embodiment is illustrated in figures Cl-CIl and is described hereinbelow. Figure Cl shows an isometric view which illustrate the toothbrush head whereby there is a top part (Ic) being the tufted part containing bristles (2c) , and a bottom part (4c) being the part which provides structural support, the abovementioned parts being separated by a flexible part (3c) . The flexible part (3c) in this preferred embodiment fully encapsulates the bottom part (4c) and also features flexible "fingers" (14c) which extend to approximately the same height as the bristles (2c) and function to massage the gums during teeth cleaning.

[044] The bottom part (4c) is made out of thin metal plate and is connected to the neck part (βc) through its tail (4cT) which slides into a horizontal slot (not illustrated) in the neck part (6c) that connects the toothbrush head to the handle (40) of the toothbrush. Figure B7 shows an exploded view of all parts. The tail

(4cT) of the bottom part (4c) is bent so that the slot

(not illustrated) is approximately in the middle plane of the neck part (βc) so as there is sufficient material on the neck part (βc) above and below the tail (4cT) for structural strength. The bottom part (4c) has a hole

(15c) at a diameter of preferably 2mm larger than the diameter of the vibrating device (7) such that the vibrating device (7) can slide through the bottom part

(4c) with a sufficient clearance. The effective contact area between the bottom part (4c) and the flexible part

(3c) can be reduced by means of holes (16c) that can be stamped out of the thin metal plate . Such a reduction in effective contact area helps to alter the dynamic behaviour of the overall structure in vibration so that there can be a greater amplitude of relative movement between the top part (Ic) and the bottom part (4c) . The bending strength of the bottom part (4c) can be increased by means of stamped ribs (4cR) as shown in Figure C8. It is also possible that the bottom part is split into two strips (4cl and 4c2) . The thickness of these metal strips must be such that there is enough structural strength. The splitting of the bottom part (4c) into two strips

(4cl and 4c2) allows them to be used as separate electrical conductors so that the wires of the vibrating device can be connected to the two aforementioned strips (4cl and 4c2) which can then be pressed into electrical connection receptors (not illustrated) appropriately positioned in the neck part (6c) .

[045] The top part is made out of a hard material preferably plastic. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (Ic) at different angles and with different methods. The flexible part (3c) may be made of an elastomer. The flexible part (3c) is formed through an overmoulding process whereby the elastomer is injection- moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould. Bonding of the elastomer to the surface of the vibrating device (7) can be avoided by means applying a thin layer of wax or lubricant onto the surface of the vibrating device prior to the moulding process.

[046] The tail (4cT) of the bottom part (4c) is secured into the slot (13c) of the neck part (6c) either by use of adhesives, or by an interference fit. Another way that the tail (4cT) of the bottom part can be secured into the neck part (6c) is to have an enlarged slot (30) as shown in Figure H2 so that the material of the flexible part

(3c) can flow into the enlarged slot (30) during the injection moulding process. This feature is described in more detail later in this text.

[047] The vibrating device (7) can be a coin-type vibrating motor or any other type of cylindrical shaped vibrating device. The vibrating device (7) slides through the centre hole (15c) in the bottom part (4c) . Figure C6 shows a side view of an exploded parts diagram illustrating the relative positioning of the bottom part

(4c) , the vibrating device (7) and the top part (Ic) . The distance between the bottom part (4c) and the top part (Ic) must be about 2mm or more. Because the thickness of the vibrating device may be more than 3mm, the vibrating device can protrude below the bottom part . A recess in the mould for the flexible part (3c) allows for a recess (5c) on the flexible part (3c) which accommodates for the protrusion of the vibrating device. Figure C4 shows a cut-out drawing illustrating the relative positioning.

[048] The vibrating device (7) can be attached to the top part (Ic) by use of adhesives or as an interference fit into a top part recess (9) . In any case, the forementioned top part recess (9) can function as a guide in positioning and attaching at the right position the vibrating device (7) onto the top part (Ic) . The vibrating device is powered from an electrical source through wires (10) which pass through a channel (12c) which passes through the flexible part (3c) and through the neck part (6c) .

[049] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Ic) and bristles

(2c) thus producing an effective cleaning action. Also, the movement of the top part (Ic) forces the "fingers"

(14c) on the flexible part (3c) to move following the motion of the top part (Ic) thus producing a soft massaging effect on the gums in the mouth. The flexible part (3c) also acts as a means of reducing the amount of vibration transmitted to the neck part (6c) and handle

(40) of the toothbrush.

[050] Yet another preferred embodiment is illustrated in figures D1-D6 and is described hereinbelow. Figure Dl shows an isometric view which illustrates the toothbrush head whereby there is a top part (Id) being the tufted part containing bristles (2d) , and a bottom part (4d) being the part which provides structural support, the abovementioned parts being separated by a flexible part (3d) . The flexible part (3d) in this preferred embodiment fully encapsulates the bottom part (4d) .

[051] The bottom part (4d) is made out of thin metal plate and is connected to the neck part (6d) through its tail (4dT) which slides into a horizontal slot (24d) in the neck part (6d) that connects the toothbrush head to the handle (40) of the toothbrush. Figure D6 shows an exploded view of all parts. The tail (4dT) of the bottom part (4d) is bent so that the slot (24d) is approximately in the middle plane of the neck part (6d) so as there is sufficient material on the neck part (6d) above and below the tail (4dT) for structural strength. The bottom part (4d) has a hole (15d) of dimensions larger than the dimensions of the cover (28) of the of the vibrating device (20) by at least lmm at each side such, so that there is sufficient clearance between the cover (28) and the bottom part (4d) .

[052] The top part is made out of a hard material preferably plastic. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (Id) at different angles and with different methods. The flexible part (3d) may be made of an elastomer. The flexible part (3d) is formed through an overmoulding process whereby the elastomer is injection- moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould .

[053] The tail (4dT) of the bottom part (4d) is secured into the slot (24d) of the neck part (6d) either by use of adhesives, or by an interference fit. Another way that the tail (4dT) of the bottom part can be secured into the neck part (6d) is to have an enlarged slot (30) as shown in Figure H2 so that the material of the flexible part (3d) can flow into the enlarged slot (30) during the injection moulding process. This feature is described in more detail later in this text.

[054] The vibrating device (7) can be a tubular-type vibrating motor or any other type of cylindrical or rectangular shaped vibrating device. The vibrating device

(7) slides through the centre hole (15d) in the bottom part (4d) . Figure D5 shows a side view of an exploded parts diagram illustrating the relative positioning of the bottom part (4d) , the vibrating device (7) and the top part (Id) . The distance between the bottom part (4d) and the top part (Id) must be about 2mm or more. Because the thickness of the vibrating device may be more than 3mm, the vibrating device can protrude below the bottom part. A recess in the mould for the flexible part (3d) allows for a recess (5d) on the flexible part (3d) which accommodates for the protrusion of the vibrating device. Figure D4 shows a cut-out drawing illustrating the relative positioning. A protrusion (19d) on the top part of part of the head (Id) allows for a recess (9d) of a depth of recess equal to the height of the protrusion

(19d) . This enables the overall thickness of the toothbrush head to be significantly reduced. The bristles

(2d) that are anchored on the protruding part (19d) are shorter than the rest of the bristles. This results in a bristle arrangement with bristles which are more stiff in the middle, thus producing a special cleaning effect.

[055] The vibrating device (7) can be attached to the top part (Id) by use of adhesives or as an interference fit into a top part recess (19d) . In any case, the forementioned top part recess (19d) can function as a guide in positioning and attaching at the right position the vibrating device (7) onto the top part (Id) . The vibrating device is powered from an electrical source through wires (not illustrated) which pass through a channel (12d) which passes through the flexible part (3d) and through the neck part (6d) .

[056] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Id) and bristles (2d) thus producing an effective cleaning action. The flexible part (3d) also acts as a means of reducing the amount of vibration transmitted to the neck part (6d) and handle (40) of the toothbrush.

[057] Yet another preferred embodiment is illustrated in figures E1-E13 and is described hereinbelow. Figure El shows an isometric view which illustrates the toothbrush head whereby there is a top part (Ie) being the tufted part containing bristles (2e) , and a side part (26e) being the part which provides structural support, the abovementioned parts being separated by a flexible part

(3e) . The flexible part (3e) in this preferred embodiment fully encapsulates the side part (26e) and also features flexible "fingers" (3eB) which extend to approximately the same height as the bristles (2e) and function to massage the gums during teeth cleaning.

[058] The side (26e) is made out of two identical thin vertical spring steel metal plates that are connected to the neck part (6e) through their tails (26eT) which slides into two vertical slots (24e) in the neck part

(6e) that connects the toothbrush head to the handle (40) of the toothbrush. The two vertical spring steel metal plates which make the side part (26e) provide structural support on the vertical plane on which they are quite stiff, but allow movement of the entire head configuration on the horizontal plane from side to side on an axis perpendicular to direction of the neck part

(6e) as shown in figure E3. Figures E5 and E6 shows the positioning of the spring steel metal plates that form the side part (26e) relative to the top part (Ie) . Bends

(26eA) on the spring steel metal plates allow for an effective following of the contour of the top part (Ie) while allowing for an aesthetically pleasing elliptical shape of the overall head configuration. These bends

(26eA) also play in important role in determining the natural frequency of vibration of the overall configuration. The thickness of the vertical spring steel metal plates forming the side part (26e) is 0.1-0.5mm depending on the exact material of construction and the desired movement aforementioned movement. The two spring steel metal plates that form the side part (26e) can also be used as separate electrical conductors so that the wires of the vibrating device can be connected to each of the two vertical spring steel metal plates which can then be pushed into electrical connection receptors (not illustrated) appropriately positioned in the neck part

(6e) to form an electrical connection to the electrical source .

[059] The top part is made out of a hard material preferably plastic. The shape of the top part (Ie) looks like an arrow (see Figure E9) to allow for the vertical spring steel metal plates to be positioned to each side as shown in Figures E5 , E6 and E7. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (Ie) at different angles and with different methods. The flexible part (3e) may be made of an elastomer. The flexible part (3e) is formed through an overmoulding process whereby the elastomer is injection-moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould. Bonding of the elastomer to the surface of the cover (28) of the vibrating device (20) can be avoided by means applying a thin layer of wax or lubricant onto the surface of the vibrating device prior to the moulding process .

[060] The tail (26eT) of the side part (26e) is secured into the slots (24e) of the neck part (6e) either by use of adhesives, or by an interference fit. Another way that the tail (26eT) of the side part can be secured into the neck part (6e) is to have enlarged slots (30V) as shown in Figure H5 so that the material of the flexible part (3e) can flow into the enlarged slots (30V) during the injection moulding process. This feature is described in more detail later in this text.

[061] The vibrating device (20) can be a tubular-type vibrating motor or any other type of cylindrical or rectangular shaped vibrating device. Figure E8 shows a side view of the side part (26e) , the vibrating device (20) and the top part (Ie) . A protrusion (19e) on the top part of part of the head (Ie) allows for a recess (9e) of a depth of recess equal to the height of the protrusion (19e) . This enables the overall thickness of the toothbrush head to be significantly reduced. Figure E13 shows a cut-out view illustrating the aforementioned protrusion, recess and the relative positioning of the vibrating device. The bristles (2e) that are anchored on the protruding part (19e) are shorter than the rest of the bristles. This results in a bristle arrangement with bristles which are more stiff in the middle, thus producing a special cleaning effect. [062] The vibrating device (7) can be attached to the top part (Ic) by use of adhesives or as an interference fit into a top part recess (9e) . In any case, the forementioned top part recess (9e) can function as a guide in positioning and attaching at the right position the vibrating device (20) onto the top part (Ie) . As shown in Figure E12, a thin cover (28) is used to prevent the elastomer material in its liquid form during injection moulding from coming into direct contact with the vibrating device. The aforementioned thin cover is press-fit into the inner perimeter of the recess (9e) on the top part (Ie) .

[063] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Ie) and bristles (2e) thus producing an effective cleaning action. Also, the movement of the top part (Ie) forces the "fingers" (3eB) on the flexible part (3e) to move following the motion of the top part (Ie) thus producing a soft massaging effect on the gums in the mouth. The flexible part (3e) also acts as a means of reducing the amount of vibration transmitted to the neck part (6e) and handle (40) of the toothbrush.

[064] Yet another preferred embodiment is illustrated in figures Fl and F2 and is described hereinbelow. Figure Fl shows an isometric view which illustrates the toothbrush head whereby there is a top part (If) being the tufted part containing bristles (2f) , and a side part (26f) being the part which provides structural support, the abovementioned parts being separated by a flexible part

Of) . The top part (If) is split into two components (IfA and IfB) as shown in Figure F2, such that a cavity (32f) is formed, and in which cavity a vibrating device (not illustrated here) is secured, which also seals the vibrating device.

[065] The side (26f) is a continuation of the neck part (6f) and is a single injection moulding into the shape of a fork. The two vertical sides can be quite thin, and provide structural support on the vertical plane on which they are quite stiff, but may be more flexible on the horizontal plane from side to side on an axis perpendicular to direction of the neck part (6f) as shown in figure El.

[066] The top part is made out of a hard material preferably plastic. The bristles can be arranged in clusters to form different profiles and may be anchored to the top part (If) at different angles and with different methods. The flexible part (3f) may be made of an elastomer. The flexible part (3f) is formed through an overmoulding process whereby the elastomer is injection- moulded into a mould which supports the top and side parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould. The elastomer also holds components IfA and IfB of the top part (If) together; flowing of the elastomer into the cavity (32f) during injection moulding is prevented due to the matching surfaces components IfA and IfB.

[066] The vibrating device can be a tubular-type vibrating motor or any other type of cylindrical or rectangular shaped vibrating device. [067] The vibrating device is held on the top part (If) by the tight fit of components IfA and IfB.

[068] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (If) and bristles (2f) thus producing an effective cleaning action. The flexible part (3f) acts as a means of reducing the amount of vibration transmitted to the neck part (6f) and handle (40) of the toothbrush.

[069] Yet another preferred embodiment is illustrated in figures G1-G5 and is described hereinbelow. Figure G5 shows an cut-out view which illustrates the toothbrush head whereby there is a top part (Ig) being the tufted part containing bristles (2g) , and a bottom part (4g) being the part which provides structural support, the abovementioned parts being separated by a flexible part (3g) . The bottom part (4g) is made out of thin metal plate and is connected to the neck part (6g) through its tail (4gT) which slides into a horizontal slot (13g) in the neck part that connects the toothbrush head to the handle (40) of the toothbrush. As shown in cut-out diagram in Figure G5, the tail (4gT) of the bottom part (4g) is bent so that the slot (13g) is approximately in the middle plane of the neck part (6g) so as there is sufficient material on the neck part (6g) above and below the tail (4gT) for structural strength.

[070] The top part is made out of a hard material preferably plastic. The bristles (2g) on the top part are not anchored but extend through the plastic base as shown in Figure Gl so that the plastic base of the top part (Ig) acts as a pivot point to each bundle of bristles. A thin membrane (3Ig) holds the bristles attached on the top part (Ig) and provides water insulation to the under-surface of the top part (Ig) . The lower part of the bristles (2gB) is fused on the bottom part (4g) as shown in Figure G5. The flexible part (3g) may be made of an elastomer. The flexible part (3g) provides a thin layer (3gP) which provides water insulation perimetrically and a base (3gB) which connects the overall head structure to the neck part (6g) as shown in Figures G3 and G4. The bonding of the flexible part (3g) may be formed by use of adhesives or ultrasonic welding or by other means at the interfaces of the sandwich structure between the flexible part (3g) and the thin insulating layer (3Ig) and between the flexible part (3g) and the bottom part (4g) . The tail (4gT) of the bottom part (4g) is secured into the slot (13g) of the neck part (6g) either by use of adhesives, or by an interference fit.

[071] The vibrating device (7) can be a coin-type vibrating motor or any other type of cylindrical shaped vibrating device. A recess (5g) on the bottom part (4g) can be created to help reduce the overall thickness at the tip of the head, that is, at the side of the head opposite to the neck part (6g) , create a perception of an lower overall thickness and give the visual effect of an "engine compartment" . Figure G5 shows a cut-out view of the toothbrush head illustrating the forementioned effect on the head thickness. The recess (5g) is sufficient to create a clearance of at least lmm between the vibrating device (7) and the bottom part (4g) .

[072] The vibrating device (7) can be attached to the top part (Ig) by use of adhesives or as an interference fit into a top part recess (9) . In any case, the forementioned top part recess (9g) can function as a guide in positioning and attaching at the right position the vibrating device (7) onto the top part (Ig) . The vibrating device is powered from an electrical source through wires (not illustrated) which pass through a channel (12g) which passes through the flexible part (3g) and through the neck part (6g) .

[073] When the vibrating device is powered up and it vibrates in operation, the energy of the vibration is concentrated primarily on the top part (Ig) and bristles

(2g) thus producing an effective cleaning action. The movement of the top part (Ig) also causes additional movement of the bristles (2g) which are pivoted on the top part (Ig) and are fixed to the bottom part (4g) as their lower part (2gB) is fused on the bottom part (4g) . The flexible part (3g) also acts as a means of reducing the amount of vibration transmitted to the neck part (6g) and handle (40) of the toothbrush.

[074] For all the preferred embodiments described above and as illustrated in the Figures, the mode by which the vibrating device is powered can be adjusted by means of appropriate electrical circuit, as shown in Figure Kl so that a vibrating action at a fixed frequency is superimposed by a pulsating frequency at which the vibrating device is powered on and off and which pulsating frequency is much lower than the vibrating frequency of the device, such that conditions close to resonance may be achieved for maximum amplitude of vibration. Figure K2 shows different possible pulsating frequencies. The pulsating frequency may also be adjusted to achieve the most comfortable feel in the mouth or to enable different modes of operation. One way that such adjustment may be done is by a rotary switch 51 on the front face of the toothbrush as shown in Figure 1. [75] Figure Kl shows a schematic diagram of the circuit in the toothbrush. A battery 50 is connectable to an oscillating module (signal generator) 52 by means of a mode selection switch 51. The oscillating module controls the movement of motor 54 through motor driver 53. Figure K2 shows three possible waveforms that can be generated by the oscillating module 52. Each waveform repeats in a cycle period T, with the motor 54 actuated for a period t.

[07S] Although several embodiments of the invention have been described above, any features of any of the embodiments may be combined together to provide further embodiments of the invention.

Claims

1. A toothbrush comprising a head connected to a handle; a top part of the head having bristles; a lower part or a side part of the head connected to the handle; a vibrating device for vibrating the bristles located in the head and fixed to the top part of the head; wherein the top part of the head is connected to the lower part or side part of the head by a flexible part, such that the transmission of vibrations from the top part of the head to the lower part or side part of the head is reduced .

2. A toothbrush as claimed in Claim 1 wherein the flexible part is formed of an elastomer.

3. A toothbrush as claimed in Claim 1 or 2 wherein the vibrating device is a vibrating micro-motor of either coin- type or tubular-type with a rotating eccentric mass.

4. A toothbrush as claimed in Claim 1, 2 or 3 wherein the top part of the head is tufted with bristles arranged in clusters to form different profiles and/or be anchored to the top part at different angles and with different methods .

5. A toothbrush as claimed in any one of Claims 1 to 4, wherein the vibrating device can be attached to the top part by use of adhesives or as an interference fit into a top part recess .

6. A toothbrush as claimed in Claim 1 wherein a neck is provided between the head and handle, and the lower part of the head and the neck part are a single plastic moulding.

7. A toothbrush as claimed in any one of the preceding claims wherein the top and bottom parts of the head are separated by the flexible part in a sandwich structure.

8. A toothbrush as claimed in any one of the preceding claims wherein the flexible part is formed through an overmoulding process whereby the elastomer is injection- moulded into a mould which supports the top and bottom parts such that bonding is formed on the surfaces of the top and bottom part as the elastomer solidifies in the mould .

9. A toothbrush as claimed in any one of the preceding Claims wherein the top part, the bottom part and the flexible part are bonded together by use of adhesives at the interfaces between the flexible part and the top part and between the flexible part and the bottom part .

10. A toothbrush as claimed one of the preceding Claims wherein a recess is provided in the lower part .

11. A toothbrush as claimed in one of the preceding Claims wherein the flexible part has a hole of diameter larger than the diameter of the vibrating device so that a clearance is formed between the vibrating device and the flexible part .

12. A toothbrush as claimed in one of the preceding Claims wherein the lower part is made out of a thin plate, and is connected to the neck by a tail which fits into a slot in the neck.

13. A toothbrush as claimed in claim 12 wherein the thin plate is formed of metal .

14. A toothbrush as claimed in Claim 12 , wherein the tail of the bottom part is bent so that the slot is approximately in the middle plane of the neck.

15. A toothbrush as claimed in Claims 12 , 13 or 14 wherein the tail of the bottom part is secured into the slot of the neck part either by use of adhesives, or by an interference fit.

16. A toothbrush as claimed in Claims 12 to 15 wherein the tail of the bottom part can be secured in the neck by use of an enlarged slot so that the material of the flexible part can flow into the enlarged slot during the injection moulding process .

17. A toothbrush as claimed in Claims 12 to 16 wherein the flexible material in the enlarged slot reduces the transmission of vibration to the neck and handle.

18. A toothbrush as claimed in one of the preceding Claims wherein ribs are formed on the bottom part to provide additional bending strength to the bottom part .

19. A toothbrush as claimed in Claim 12 wherein holes provided in the tail of the bottom part can be used to adjust the flexibility of movement of the head assembly into the neck.

20. A toothbrush as claimed in one of the preceding Claims wherein the bottom part is completely encapsulated by the flexible part .

21. A toothbrush as claimed in one of the preceding Claims wherein the flexible part has flexible fingers that extend to approximately the same height as the bristles .

22. A toothbrush as claimed in one of the preceding Claims wherein the bottom part has a hole of a diameter of preferably 2mm larger than the diameter of the vibrating device such that the vibrating device can slide through the bottom part with a sufficient clearance.

23. A toothbrush as claimed in one of the preceding Claims wherein the effective contact area between the bottom part and the flexible part is reduced by means of holes in the bottom part .

24. A toothbrush as claimed in one of the preceding Claims wherein the bottom part is split into two strips, these two strips forming separate electrical conductors connected to the vibrating device and which can be pressed into electrical connection receptors appropriately positioned in the neck.

25. A toothbrush as claimed in Claim 8 wherein a thin layer of wax or lubricant is applied onto the surface of the vibrating device prior to the moulding process to avoid bonding of the elastomer to the surface of the vibrating device .

26. A toothbrush as claimed in any one of the preceding Claims wherein a recess on the flexible part accommodates the protrusion of the vibrating device below the bottom part .

27. A toothbrush as claimed in Claim 21 wherein movement of the top part forces the fingers on the flexible part to move following the motion of the top part for producing a soft massaging effect on the gums in the mouth.

28. A toothbrush as claimed in any one of the preceding Claims wherein the vibrating device is covered by a thin cover to prevent the flexible material from coming in contact with the eccentric mass during the injection moulding process .

29. A toothbrush as claimed in Claim 28 wherein the thin cover (28) is made out of metal or plastic of a melting point higher than the temperature of flexible part during injection moulding.

30. A toothbrush as claimed in Claims 28 or 29 wherein the bottom part has a hole of dimensions larger than the dimensions of the cover of the of the vibrating device by at least lmm at each side such that there is sufficient clearance between the cover and the bottom part .

31. A toothbrush as claimed in any one of the preceding Claims wherein the vibrating device is slideable through a centre hole in the bottom part .

32. A toothbrush as claimed in any one of the preceding Claims wherein a protrusion provided on the top part of the head provides a recess of a depth of recess equal to the height of the protrusion, in which recess the vibrating device is secured.

33. A toothbrush as claimed in Claim 32 wherein bristles anchored on the protrusion are shorter than the rest of the bristles, such that they are stiffer.

34. A toothbrush as claimed in one of the preceding Claims wherein the top part is the tufted part containing bristles, the side part being the part which provides structural support, the abovementioned parts being separated by a flexible part such that the flexible part fully encapsulates the side part .

35. A toothbrush as claimed in any one of the preceding Claims wherein the side part is made out of two identical thin vertical spring steel metal plates which provide structural support on the vertical plane on which they are quite stiff, but allow movement of the entire head configuration on the horizontal plane from side to side on an axis perpendicular to direction of the neck.

36. A toothbrush as claimed in Claim 35 wherein the vertical spring steel metal plates are connected to the neck through tails that slide into two vertical slots in the neck.

37. A toothbrush as claimed in any one of the preceding Claims wherein the top part resembles an arrow shape such that the side part can be positioned around the top part.

38. A toothbrush as claimed in any one of the preceding Claims wherein the side part is positioned at a level of approximately lmm lower than the top part .

39. A toothbrush as claimed in Claims 35 wherein there are formed bends (26eA) on the spring steel metal plates.

40. A toothbrush as claimed in claims 35 or 39 wherein the thickness of the vertical spring steel metal plates forming the side part (26e) is 0.1-0.5mm depending on the exact material of construction and the desired movement .

41. A toothbrush as claimed in claims 35, 39 or 40 wherein the two spring steel metal plates that form the side part can also be used as separate electrical conductors such that wires of the vibrating device can be connected to each of the two vertical spring steel metal plates which can then be pushed into electrical connection receptors appropriately positioned in the neck to form an electrical connection to an electrical source.

42. A toothbrush as claimed in Claim 28 wherein the thin cover is press- fit into the inner perimeter of a recess on the top part .

43. A toothbrush as claimed in Claim 28 wherein a thin layer of wax or lubricant is applied onto the surface of the vibrating device prior to the moulding process to avoid bonding of an elastomer to the surface of the cover of the vibrating device.

44. A toothbrush as claimed in Claim 36 wherein the tail of the side part is secured into the slots of the neck by use of adhesives, or by an interference fit.

45. A toothbrush as claimed in Claim 36 wherein the tail of the side part can be secured into the neck by use of enlarged slots so that the material of the flexible part can flow into the enlarged slots during the injection moulding process and bond the tail to the neck as it solidifies .

46. A toothbrush as claimed in Claim 36 wherein holes provided in the tail can be used to adjust the flexibility of movement of the side part relative to the neck and the dynamic behaviour of the overall head structure during vibration.

47. A toothbrush as claimed in Claim 1 wherein the bristles on the top part are not anchored but extend through a plastic base, and a bottom part (4g) that is made out of a thin metal plate, with the lower end of the bristles being fixed onto the thin metal plate.

48. A toothbrush as claimed in Claim 47 wherein the bristles are fixed onto the thin metal plate by thermal fusion.

49. A toothbrush as claimed in Claims 47 or 48 wherein the plastic base of the top part acts as a pivot point to each bundle of bristles as the top part vibrates.

50. A toothbrush as claimed in Claims 47 or 48 wherein a thin flexible membrane holds the bristles attached on the top part and provides water insulation to the under-surface of the top part .

51. A toothbrush as claimed in Claims 50 wherein the thin flexible membrane is made out of elastomer material .

52. A toothbrush as claimed in Claims 47 to 50 wherein there is a flexible part which consists of a thin layer perimetrically disposed that provides water insulation and a base which connects the overall head structure to the neck.

53. A toothbrush head as claimed in Claims 50 to 52 wherein the flexible part may be bonded to the thin flexible membrane, the bottom part, the top part, and the neck by use of adhesives or ultrasonic welding or by other means at the interfaces between each component .

54. A toothbrush as claimed in Claim 47 wherein the tail of the bottom part is secured into the slot of the neck either by use of adhesives, or by an interference fit.

55. A toothbrush as claimed in Claim 47 wherein a recess is provided on the bottom part.

56. A toothbrush as claimed in Claims 47 to 55 wherein movement of the top part also causes additional movement of the bristles which are pivoted on the top part and are fixed to the bottom part as their lower part is fused on the bottom part .

57. A toothbrush as claimed in any one of the preceding claims wherein the mode by which the vibrating device is powered can be adjusted by means of an electrical circuit so that a vibrating action at a fixed frequency is superimposed by a pulsating frequency at which the vibrating device is powered and which pulsating frequency is much lower than the vibrating frequency of the device, such that conditions close to resonance may be achieved for maximum amplitude of vibration.

58. A toothbrush as claimed in Claim 57 wherein the pulsating frequency may be adjusted by means of an electrical switch or appropriate logic circuitry or other electronic means in order to achieve the most comfortable feel in the mouth or to enable different modes of operation.

59. A toothbrush as claimed in Claim 57 wherein the switch is a rotary switch.

60. A toothbrush as claimed in any one of the preceding claims wherein the flexible part has an aperture, the vibrating device extending through the aperture in the flexible part .

61. A toothbrush and a toothbrush head as described and with reference to and as shown in the accompanying drawings .