WO1997004719A1

WO1997004719A1 - Toothbrush

Info

Publication number: WO1997004719A1
Application number: PCT/GB1996/001804
Authority: WO
Inventors: Timothy Nathaniel Stewart
Original assignee: Timothy Nathaniel Stewart
Priority date: 1995-07-29
Filing date: 1996-07-26
Publication date: 1997-02-13
Also published as: AU6621996A; GB9515629D0

Abstract

The invention relates to toothbrushes and is particularly concerned with powered toothbrushes. The objective of the invention is to provide a toothbrush that seeks to minimise the manual movement of the brush during use, which objective is met by a construction comprising a carrier (2), a support arm (3) rotatively secured to the carrier, a cleaning head (4) at the outer, free end of the support arm, and a drive means (6) associated with the carrier to cause the rotation of the arm. Most desirably the support arm can be selectively rotated in opposite directions.

Description

TOOTHBRUSH

This invention relates to toothbrushes. Predominantly, toothbrushes are manually operated, and effective cleaning of the teeth is reliant on the dexterity of the hands of the user. For those with disabilities affecting the hands and arms, the infirm, and those weakened by illness, manual cleaning of the teeth can be a difficult task that cannot be performed effectively. Even with the able bodied, manual cleaning of the teeth can be improved upon. To assist in the cleaning of teeth a variety of powered toothbrushes are available. Ordinarily it has been the case of applying an oscillatory movement to an arm carrying the bristle head from a small mains or battery operated electric motor located in the toothbrush handle or body from which the arm extends.

The result is a short arcuate movement of the bristle head, not of itself ideal in removing debris from the vertical junction between adjacent teeth, and therefore still requiring an appreciable degree of manual movement to supplement the oscillatory movement of the bristle head to bring about effective cleaning of the teeth.

The object of the invention is to provide a powered toothbrush capable of minimising the requirement to move the toothbrush manually. According to the present invention, a toothbrush comprises a carrier, a support arm rotatively secured to the carrier, a cleaning head at the outer, free end of the support arm, and a drive means associated with the carrier to cause the rotation of the arm. Most desirably, the support arm may be selectively rotatable in opposite directions for more effective cleaning of the fronts and backs of the upper and lower sets of teeth. In addition to lending considerable assistance in correct cleaning, the selection of rotation is to cause a rotation of the cleaning head that is in the direction from the gum to the outer extremity of the teeth, to avoid the possibility of damage being caused to the gums. Further deisrably, and in addition to the selective rotation of the cleaning head, the cleaning head may be caused to reciprocate in an axial direction, whereby to provide a compound movement of the cleaning head that adds significantly to the cleaning action on the teeth. The carrier may be a housing to serve as the handle of the toothbrush, and a small mains or battery operated electric motor may be located in the housing to apply a rotary drive to the support arm. Equally, the carrier may be attached such as by a flexible drive to a remote motor, with a connection through the carrier to the support arm.

The support arm may be detachably secured to the carrier, or the cleaning head may be detachably mounted on the end of the support arm. Thus, one carrier unit can serve a number of users, each of whom would have their own support arm/brush head for attachment to the carrier as and when cleaning of their teeth is required.

The cleaning head may be of bristle construction and the bristles of the bristle head may be of uniform length to provide a bristle head of generally cylindrical character. Preferably, however, the bristle head is shaped to provide a tooth-like profile at the periphery of the bristle head, and further preferably, the crests of the tooth-like profile have a helical configuration along the length of the bristle head.

Equally, the cleaning head can be formed as a generally cylindrical member of a relatively soft or resilient material, such as for example foam rubber, to suit users with a medical condition making it essential that the gums are not damaged and caused to bleed, or those with gum disorders of a painful nature.

To protect such as the inner faces of the lips and the cheeks of the user when cleaning the outer faces of the teeth, and the tongue of the user when cleaning the inner 5 surfaces of the teeth, it is preferred to provide a guard to overlie the rotary cleaning head to one side.

The toothbrush of the invention can be further enhanced by providing a fluid supply to the cleaning head such as down a bore formed in the support arms and associated o apertures through the wall of the support arm and communicating with the cleaning head. The toothbrush of the invention can be still further enhanced by providing for the vacuum extraction of fluid from the mouth of the user, either through the bore previously used to supply fluid, or through 5 a separate channel formed in or associated with the support arm to allow the continuous supply and removal of fluid during use. Preferably, a bleed hole to atmosphere is associated with the vacuum extraction means and to avoid an excessive build-up of vacuum in the mouth of the user should the mouth inadvertently close on to the cleaning head.

In its basic form of construction, the cleaning head can simply be placed by the user at the junction of the teeth and the gums and the drive activated, and with the cleaning head rotating, the toothbrush moved gently over the length of the teeth. The rotation of the brush generates a vertical scrubbing action against the teeth, ideally suited to cleaning not only the face of the teeth but also the junction between adjacent teeth. By providing for the selective opposite rotation of the cleaning head, the direction of rotation can be selected such that when cleaning the front or the back of the upper or the lower set of teeth, the direction of rotation can be selected to drive debris towards and clear of the outer edge of the teeth. By being able to select the direction of drive, the toothbrush of the invention enables both left hand and right hand usage. When provided, the additional reciprocatory motion applied to the cleaning head adds noticeably to the cleaning action on the face of the teeth without affecting the ability of the toothbrush to avoid damage to the gums and lips of the user.

Several embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:- Figure 1 is a front elevation of one embodiment of toothbrush in accordance with the invention;

Figure 2 is an end view of the toothbrush of Figure 1; Figure 3 is a schematic cross-sectional view of the toothbrush of Figure 1 ;

Figure 4 corresponds to Figure 3 but shows a second embodiment of toothbrush in accordance with the invention; and

Figure 5 is a perspective view of a third embodiment of toothbrush in accordance with the invention.

In the drawings, a toothbrush 1 is formed by a carrier or handle portion 2, and a support arm 3 on which is positioned a cleaning head 4. At the opposite (innermost) end of the support arm, reduction gearing 5 is provided to connect the support arm 3 to a motor 6 located in the carrier, the motor 6 being driven by batteries 7 also located within the carrier. On the carrier switch means 8 are provided whereby the direction of drive of the motor can be selectively reversed, and whereby to cause a rotation of the support arm and hence the cleaning head in a required direction. The arrangement may be such that in addition to a battery drive, mains drive can be employed. Thus, as is shown particularly by Figure 2, a connection 9 to mains may be provided, which connection to mains may also be employed to recharge the batteries 7, when rechargeable batteries are employed.

At the outer end of the carrier and where the cleaning head is positioned, the carrier is so-formed as to provide a guard 10 to overlay a part of the cleaning head to protect the lips, cheeks, and tongue of the user.

The cleaning head 4 is preferably of bristle construction, the bristles 11 of which are of uniform length to form a generally cylindrical structure. Desirably, however, the bristles are shaped to provide a tooth-like profile at the periphery, and the crests of the tooth-like profile having a helical configuration along the length of the cleaning head.

Thus, in its basic form of construction the cleaning head 4 can simply be placed by the user at the junction of the teeth and gums, and the switch 8 activated to cause the cleaning head 4 to be rotated. When it is the front of the teeth that are being cleaned, the direction of drive is selected to provide a downward motion of the bristles 11 from the gum to the edge of the teeth, and when it is the back of the teeth that are being cleaned, an opposite direction of drive is selected again to result in a bristle movement direction from the gum to the teeth edge.

In addition to the selective rotary motion imparted to the cleaning head, it can, with advantage, be so arranged that during rotation in either direction an axial oscillatory motion can be imposed. Thus, as is shown schematically in Figure 4, the support arm 3 may be formed from a tough plastics material, and at a point along the length of the support arm, where it is positioned within the carrier 2, a sector or a sleeve 12 of ferro-magnetic material may be provided, surrounded by a small solenoid 13 connected to the batteries 7 via the switch 8, with an interposed make-and- break contact 14. To the opposite side of the reduction gears to the support arm, a return spring 15 is provided. The reduction gearing 5 may have one of its gear wheels of an enlarged length to permit a sliding motion as between the two gears without the disconnection of the one from the other. Thus, and in this form of construction, when the toothbrush is switched on, and to rotate the cleaning 4 in either direction, there is a rapid activation and de-activation of the solenoid 13 to cause the ferro-magnetic sector 12 on the support arm to be drawn into the solenoid (when switched on) and ejected from the solenoid (when switched off) under the action of the spring 15.

To enhance the effectiveness of the toothbrush of the invention still further, it may be adapted to serve as the toothbrush of the equipment described and claimed in European Patent Application 91919704.6, a construction where water is provided to the cleaning head and extracted from the mouth of the user by vacuum, thereby allowing the toothbrush to be used most effectively, and without any discomfort to, such as, patients who must be left in a prone position. Thus as is shown in Figures 2 and 5, a water inlet 16 and a water outlet 17 may be provided on the carrier, for connection to a water feed tube 18, and a vacuum extraction tube 19 leading to transportable equipment 20 on which is provided vacuum pump means and water supply means. Within the carrier, inlet and outlet water passageways are provided from the inlet 16 and outlet 17 leading to the cleaning head 4.

Claims

1. A toothbrush characterised by a carrier 2, a support arm 3, rotatably secured to the carrier, a cleaning 4 at the outer free end of the support arm 3, and a drive means 6 associated with the carrier to cause the rotation of the arm 3.

2. A toothbrush as in Claim 1 , characterised in that the support arm 3 is selectively rotatable in opposite directions whereby to allow for more effective cleaning of the fronts and backs of the upper and lower sets of teeth.

3. A toothbrush as in Claim 1 or Claim 2, characterised in that the carrier 2 is a housing to serve as the handle of the toothbrush and a mains or battery operated electric motor 6 is located in the housing to apply a rotary drive to the support arm 3 in accordance with the setting of an ON/OFF/DIRECTION switch 8.

4. A toothbrush as in any of Claims 1 to 3, characterised in that the support arm 3 constitutes a flexible drive from the motor to the cleaning head.

5. A toothbrush as in any of Claims 1 to 3, characterised in that the cleaning head 4 is detachably mounted on the end of the support arm 3.

6. A toothbrush as in any of Claims 1 to 5, characterised in that the cleaning head 4 is of bristle construction and the bristles 11 of the bristle head are of uniform length to provide a bristle head of a cylindrical character.

7. A toothbrush as in Claim 6, characterised in that the periphery of the bristles 11 are formed to a tooth-like profile, with the crests of the tooth-like profile having a helical configuration along the length of the bristle head.

8. A toothbrush as in any of Claims 1 to 5, characterised in that the cleaning head 4 is formed as a generally cylindrical member of a relatively soft, or resilient, material such as, for example, foam rubber.

9. A toothbrush as in any of Claims 1 to 8, characterised in that to protect the inner faces of the lips, cheeks, and tongue, of the user, a guard is provided at the end of the carrier to overlie partially the cleaning head.

10. A toothbrush as in any of Claims 1 to 9, characterised in that in addition to a rotary motion imposed on the cleaning head 4, the cleaning head 4 during use of the toothbrush is subjected an axial oscillation.

11. A toothbrush as in any of Claims 1 to 10, characterised in that a water supply 16, 18 is provided to the carrier to emerge at the cleaning head 4, and a vacuum extraction means 17, 19 is provided that emerges at the cleaning head 4 whereby to allow the supply of fluid to the cleaning head and the extraction of fluid from the mouth of the user during use of the toothbrush.