GB2159046A - Vibratory cleaning device - Google Patents

Abstract

A dental cleaning or polishing device has a cleaning or polishing head (3) located at the end of a stem (2) secured to an electrical vibrator unit (1) for imparting axial reciprocating motion to the stem (2). At least a portion of the head (3) is disposable, being made, for example, of a flexible plastics material with a textured cleaning or polishing surface. A variety of different head configurations are disclosed including arrangements incorporating a disposable flexible cover member supported by a base portion in the head which is resilient in a direction perpendicular to the surface to be cleaned yet rigid in a direction parallel to the stem axis so that the head adapts to the shape of the surface to be cleaned without absorbing the axial vibrations. <IMAGE>

Description

SPECIFICATION A dental cleaning or polishing device This invention relates to a cleaning or polishing device which is primarily for dental use, but can also be used for cleaning or polishing other objects such as jewellery. The device comprises a cleaning or polishing head attached by a stem to a drive unit.

Electrically or mechanically driven toothbrushes generally have a brush head attached to a stem which is mounted in a body part of the device and executes an oscillatory pivoting motion about the axis of the stem when an electric or other motor in the body part is energised. The bristles of the brush extend laterally to the stem axis and thus, when the device is held in a normal position for cleaning the surfaces of the teeth, the ends of the bristles move up and down on the teeth, i.e. they reciprocate towards and away from the gums. This has the advantage that the bristles move across rather than along the crevices between the teeth and the gums where plaque forms.

It is also known to move the head axially of the stem, but, as with all toothbrushes, it is difficult to clean thoroughly all the tooth surfaces.

According to this invention there is provided a cleaning or polishing device comprising a cleaning or polishing head located at the end of a stem, wherein the stem is secured to a vibrator unit for imparting an axial reciprocating motion to the stem, and at least a portion of the head is disposable. The head may be shaped so that it can be located in and move within the tooth/gum crevices, and if required between adjacent teeth, to remove plaque. So that the device can be safely used as a domestic tooth cleaning device, the removable head is preferably of a flexible, yielding, non-metallic material, such as a plastics material which is sufficiently inexpensive to be disposed and replaced on virtually every occasion the device is used.In one embodiment of the invention the device has a cleaning or polishing head which is a textured double sided disposable pad fitted to the end of a stem arranged to move axially relative to a body part of the device. The pad is shaped to cover one tooth at a time with parts of its perimeter being capable of being seated in the crevice between the tooth and the gum margin where it vibrates transversely relative to the tooth surface and along the crevice. The amplitude of vibration of the pad is preferably very small, typically less than 1 mm, and can be provided by an electrical vibrator in the body part. Such a vibrator may comprise simply an armature secured to the stem and caused to vibriiate by the passage of an alternating current through an electrical winding.

The vibration may be ultrasonic. Other types of drive unit can be used, for instance a small motor coupled to the stem via an appropriate mechanism to produce axial movement of the stem, or a make and break buzzer unit, or a mechanical vibrator or motor. The vibrating mechanism may be attached directly to the stem, or may be attached to the body which in turn transmits vibration to the stem. In general terms, the drive unit is a device which produces relative vibratory motion between two of its component parts with one part being attached to the stem and the other part to the body of the device.

In addition to the advantage of being cable to remove plaque, the relatively small movements of the head allow the domestic user particularly to position the head accurately and to be aware of the exact area being cleaned or polished since, apart from the vibrating movements the head can be held stationary and cleans where it touches. In this way each tooth can be cleaned in a methodical and controlled fashion.

The disposable head portion provides a practical and convenient means of using fresh, unworn and sterile components as often as necessary and with minimal expense. In some embodiments disclosed herein, the disposable heads and their manner of fixation to the stem force the user to replace each head with a fresh one by making it impossible to remove a worn or soiled head from the stem without destroying the head. In other embodiments, the cleaning or polishing surface and its supporting structure is arranged to be readily deformable in a direction perpendicular to the stem axis but comparatively rigid in a direction parallel to the axis to enable the head automatically match the tooth profile without absorbing the axial vibration of the stem to any significant extent.

A wide variety of stem attachments can be used, including interdental cleaning elements.

The invention will now be described by way of example with reference to the drawings in which: Figure lisa side elevation of a tooth cleaning or polishing device in accordance with the invention; Figure 2 is a side elevation of a first disposable head portion prior to attachment to the device of Figure 1; Figure 3 is a side elevation of the end of a stem forming part of the device of Figure 1; Figure 4 is a sectioned plan view of the disposable head portion of Figure 2; Figure 5 is a sectioned end view of one half of the head portion of Figure 2; Figure 6 is an end elevation of a disposable interdental wedge; Figure 7 is a side elevation of the wedge of Figure 6; Figure 8 is a side elevation of a stem suitable for receiving the wedge of Figures 6 and 7;; Figures 9r13 are exploded perspective views of third, fourth, fifth, sixth, and seventh head portions and stem embodiments; and Figures 13A and 138 are plan views of alternative components for use in the head shown in Figure 13.

Referring to Figures 1 to 5, a tooth cleaning or polishing device in accordance with the invention has a body part 1, stem 2 and a tooth-contacting cleaning or polishing head 3. The body part 1 houses an electrical drive unit 4 and a battery or transformer 5, both shown by dotted lines. An armature element 6 is rigidly fixed to the stem 2, and is free to move axially in the nose of the body part 1.

The end of the stem 2 and the head 3 are shown enlarged in Figures 2 to 5. In this embodiment the head 3 comprises a disposable nylon pad in two halves 7 and 8 of generally oval outline, each pad having an outer textured surface which is concave on one pad and convex on the other. The curve of these surfaces are designed to match the curves of tooth surfaces, the radius of curvature of a line joining the sides of a pad being less than the radius of curvature of a line joining the two ends. In Figures 2 and 3 the two pad halves 7 and 8 are shown in an opened out configuration prior to fitment to the stem 2.Each pad half has a recess for the stem 2 and one has a pair of studs 9 which snap into corresponding sockets 10 in the other pad half when the two halves are fitted to an end plate 11 of the stem (Figure 3) and broughttogetherto enclose the end plate 11 which has apertures 12 for the studs 9.

Figures 4 and 5 are sections along the lines IV-lV and V-V respectively in Figure 2.

The end plate 11 may be flat or curved and the interfacing inner surfaces of the pad 7,8 are correspondingly shaped.

The surface texture may be produced by integrally moulded, very short bristles, spikes, blades or pimples, or by other techniques such as deposited fibres.

A range of pads can also be provided, for example in pairs of two concave pad halves, one concave and one convex as shown, or two convex pad halves.

A further embodiment of cleaning or polishing head shown in Figures 6 and 7 comprises an interdental wedge 13 for use between the teeth. The wedge may have smooth or textured surfaces, and is preferably detachably mounted in a tubular portion 14 of the stem 2 (see Figure 8) by means of a poppet element 15 which snaps into a hole or recess 16 in the portion 14. Alternatively, the wedge 13 may be a friction fit in the portion 14. The wedge 13 may be hollow, in which case it may contain a polishing agent, and it may also be flexible.

Figure 8 also shows a jointed stem 2 which is applicable to all embodiments of the invention, to aliow interchangeability of stem end portions.

Further stem and head configurations are shown in Figures 9 to 13. Figure 9 is an exploded perspective view of a cleaning or polishing device having a curved stem 2 suitable for mounting on a vibratory drive unit in the manner illustrated in Figure 1.The stem 2 terminates in a receptacle 17 shaped to carry internally a small disposable cleaning or polishing head portion 18 which is shaped to be inserted in the receptacle 17 with one end projecting. The receptacle and the disposable head portion are shown here as being rectangular in section, but they may be of any suitable shape.The disposable head portion 18 has a pip 19 on its side which locates positively in a hole 20 in the side of the receptacle so that the head portion 18 is correctly positioned, with the cleaning end standing proud, and so that, given a suitably weak material such as expanded polystyreneforthe head portion, it can only be removed by breaking it. In this example, the cleaning end is coated with a mildly abrasive layer 21 to aid cleaning or polishing.

The disposable head of Figure 9 is easily inserted and removed, and has the advantage of being extremely inexpensive to manufacture. Alternative heads and receptacles are shown in Figures 10 and 11 which also have these advantages. Referring to Figure 10, the receptacle 17 can comprise a pair of jaws 17A and 17B moulded integrally with the stem 2, the head portion 18 (again expanded polystyrene or other suitable material) having corresponding grooves or recesses 18A and 18B to receive the jaws 17A, 17B when the head portion is slid onto the receptacle. As before, snap-locating features may be incorporated in head portion 18 and receptacle 17 to locate the head portion more firmly and to result in the head portion being destroyed on removal.

The head portion of Figure 10 fits between two jaws; that of Figure 11 fits around the end portion of a stem having two parallel outwardly projecting edges 17Cand 17D. Corresponding internal grooves 18C and 18D are provided in the head portion 18 which also has a separately affixed polishing layer 18E.

Polystyrene foam has been mentioned as a suitable material for the head. Such a head would be moulded. Other materials can be employed, some of which allow manufacture by extrusion. As an alternative to polystyrene, the head material may include a paperorwood-based material, rubber, or a fibrous nylon material, amongst others. The cleaning or polishing layer may be chamois leather, suede, fibrous material, etc.

Referring now to Figure 12, a further stem and head configuration has a flexible plastics half-ring 22 projecting perpendicularly to the stem axis. The geometry of the ring 22, being considerablywider than it is thick enables it to yield readily in the perpendicular direction to conform to the shape of the tooth surface, but by resisting lateral deformation transmits the full amplitude of the axial stem vibrations to the cleaning surface. In this case, the cleaning surface is provided by a soft flexible cover member 23 which is disposable and may be a snap fit on the ring 22. As in the embodiments described above, the cover member preferably has a textured surface, and may itself be shaped by, for example, providing a ridge perpendicular to the axis of vibration as shown.

Yet a further embodiment is shown in Figure 13.

This possesses similar resilient qualities to the embodiment of Figure 12 inasmuch as it is able to conform dynamically to the shapes of different tooth surfaces without absorbing the axial vibrations of the stem 2. Here, the head comprises a hollow receptacle 24 on the end of the stem 2, a soft, resilient cushion 25 in the base of the receptacle, a stack of thin plastics leaves 26, and a cover member 27. An important property of the leaves 26 is that they slide easily relative to each other so that when pressure is applied at the exposed end the end profile of the stack resiliently matches the tooth profile and returns to its former profile when the pressure is removed due to the elastic nature of the cushion 25. Polyethylene film is a suitable material for the leaves 26. As before, a soft disposable cover member with a textured cleaning surface fits over the support constituted by the stack of leaves 26.

Each leaf in the stack 26 may be shaped as shown in Figures 13A and 13B to provide a snap feature 26A or 26B for retaining the disposable cover member 27.

Further embodiments not shown in the drawings include an inflatable support for a disposable cover member, and a disposable portion including a reservoir of cleaning agent such as a dentifrice. Each new disposable portion includes a new measure of dentifrice which may be released by puncturing a thin flexible container forming part of the disposable head portion. Alternatively, the disposable head portion may include a recess or chamber which is initially covered by, for example, a removable adhesive strip to retain a measure of cleaning agent.

Claims (14)

1. A cleaning or polishing device comprising a cleaning or polishing head located at the end of a stem, wherein the stem is secured to a vibrator unit for imparting an axial reciprocating motion to the stem, and at least a portion of the head is disposable.

2. A device according to claim 1, wherein the disposable head portion comprises a flexible cleaning or polishing pad.

3. A device according to claim 2, wherein the pad has a textured cleaning or polishing surface.

4. A device according to claim 2 or claim 3, wherein the pad comprises a removable flexible cover member secured over a flexible support.

5. A device according to any preceding claim, wherein the head has a cleaning or polishing surface which is backed by means having differential flexibility to allow the surface to conform to different tooth profiles during use whilst allowing vibratory movement to be transmitted from the stem to the said surface.

6. A device according to any of claims 2 to 5, wherein the cleaning or polishing surface projects from the stem perpendicularly to the axis of the stem.

7. A device according to any of claims 2 to 6, wherein the cleaning or polishing surface is so arranged that, in use, it is the only part of the device that contacts the surface to be cleaned or polished.

8. A device according to claim 4, wherein the flexible support is resilient in a direction perpendicular to the axis of the stem but rigid in a direction parallel to the said axis.

9. A device according to any preceding claim, wherein the disposable head portion is made of plastics material.

10. A device according to any preceding claim wherein the disposable head portion includes a reservoir containing a cleaning agent.

11. A device according to any preceding claim for dental use.

12. A device according to claim 11, wherein the disposable head portion is an interdental stick.

13. A device according to claim 11 or claim 12, wherein the stem or head includes an interface allowing attachment of differently shaped disposable head portions.

14. A dental cleaning or polishing device constructed and arranged substantially as herein described and shown in the drawings.