GB2074876A - Device for supporting thread - Google Patents

Abstract

A device for supporting a tensioned thread comprises a body 11 and a relatively movable arm 18 which have respective attachment points 13, 19 for the thread. The thread is attached with the arm in a part-extended disposition, and the arm is then locked in a fully-extended disposition to tension the thread. As described the device is a dental floss dispenser. Operation of a button 29 releases the lock for the arm. The attachment points may be in the form of cleats (as shown) or screws (not shown). <IMAGE>

Description

SPECIFICATION Device for supporting thread The present invention relates to a device for supporting thread and more particularly to a device having two relatively movable portions to which ends of the thread, for example dental floss, may be secured.

When employing a thread it is often necessary that it be taut. It is of course possible to hold the thread taut between one's hands but this requires both hands to be occupied, and may be uncomfortable. Furthermore it may not be possible to reach awkwardly located points; in the case of dental floss for example it is difficult to clear all the desired surfaces of one's teeth.

This problem may be overcome by tying the thread between two fixed securing points, for example between the ends of an arcuate or generally U-shaped arm member, so that the thread corresponds to the string of a bow. With such an arrangement it is difficult to maintain the thread at its desired tautness whilst securing it to the fixed points.

According to the present invention there is provided a device for supporting a thread comprising a body member, which has a first attachment point for a thread, an arm member, which has a second attachment point for a thread and which is movable relative to said body member to vary the separation of said first and second attachment points, and a means for locking said arm member to said body member in a desired relative position.

The locking means can preferably lock the arm member to said body member in a plurality of relative positions. This enables the arm member to be locked in a first position, and a thread to be secured to the attachment points with the thread in a slack condition; the arm member is then locked in a second position with the attachment points further apart thus subjecting the thread to a desired tension.

The body member may include a housing for storing the thread to be used, and an opening may be provided in the body member to permit dispensing of the thread.

A preferred embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings, of which: Fig. 1 shows a side view of a dental floss supporting device according to the present invention; Fig. 2 shows a front view of the device of Fig. 1; Fig. 3 shows a side view of the device with the arm member extended; Fig. 4 shows a front view of the arm member of the above device; Fig. 5 shows a side view of the arm member; Fig. 6 shows a side sectional view of the device; Fig. 7 shows a sectional view along the line 7-7 of Fig. 6; and Fig. 8 shows a side view of a modification of the device of Fig. 1 with its arm member extended.

Referring now to Fig. 1 of the drawings there is shown a device 10 for dispensing and supporting dental floss. The device comprises a body or housing portion 11 and a removable cap 12 which is a snap-fit on to the body portion. Body 11 and cap 12 are made of plastics material, e.g.

polypropylene. The body 11 is provided at its top with a first thread attachment point in the form of a cleat 13 having two crossed slits which form four projections arranged in a square formation.

In a shallow recess in the surface of body 11 there is provided a sheet-metal plate 14 which is secured to the body by a pin 1 5. Pin 1 5 may extend to the other side of body 11 and be used ta fasten together the two halves of the upper part of the body. Raised up from metal plate 14 there is a cutting portion 1 6 which may be used to cut the dental floss.

At the front of the body there is provided a slot 17, see Fig. 2, through which dental floss contained in the body may be drawn.

The two halves comprising the lower part of body 11 are hinged together at 22 to permit access to the contents of the body.

Above the top of the body portion 11 there is provided a generally L-shaped movable arm 18 which is shown in an extended position in Fig. 3.

The arm 1 8 has at its upper end a second thread attachment point 1 9, similar to that on body 11.

At its other end arm 18 is provided with a foot 21.

A series of raw-tooth projections 20 are provided along the vertical section of arm 18. The arm is preferably made of A.B.S. or nylon material.

Referring now to Fig. 6 the disposition of arm 1 8 in its unextended position may be seen. The upper part of the vertical section of arm 1 8 is engaged by a nose 30 on a button 29. A spring means in the form of a resilient strip 31 biasses the button 29 towards arm 1 8. The shape of nose 30 corresponds to that of the gaps between teeth 20. The button is actuable from outside the body 11 and is preferably made of acetal plastics material.

A roll 33 of wound dental floss is shown inside body 11. The roll is mounted on a spigot and socket connection 34 which together with a second such connection 35 holds together the two halves of the botton part of body 11.

Connections 34 and 35 are interference fits. Also provided inside body 11 are raised wall portions 36, 37 adjacent the slot 1 7. When floss is removed from roll 33 via slot 17, portions 36, 37 hold the floss between them and prevent it from disappearing back inside the body.

In use a roll of dental floss 33 is inserted in body 11 and the end of the thread is passed through slot 1 7. Body 11 is then closed. Cap 12 is removed and arm 1 8 is extended to the position shown in Fig. 3. As the arm approaches this position the sloping face of nose 30 rides up the sloping face of the top tooth 20, and as the position is reached the nose snaps into the gap between the first and second teeth. Dental floss is then pulled out of body 11 and wrapped securely around both cleats 13, 19 or held in the slits. At this stage the floss between the cleats will be relatively slack. Arm 1 8 is then pulled further out of the body portion 11. This movement is facilitated by the sloping face of nose 30 riding up the sloping faces of successive teeth 20.The number of notches moved depends upon the desired tension of the floss. As shown there is a choice of four different positions after the first one.

Of course a position other than the top one could be used as the first position, but this would then reduce the extra tensioning available. The device is now ready for use.

After use the floss is released from cleats 13, 19 and the floss is drawn against the edge of cutting portion 1 6 so that the used floss may be discarded. To return arm 1 8 to the body portion, the user pushes button 29 to the left, as shown in Figs. 3 and 6. This disengages nose 30 from teeth 20 and arm 18 may be readily slid home. Cap 12 is then snap-fitted back into place.

The above embodiment has the advantage that it is not necessary to tie the dental floss to the cleats whilst the floss is under tension. Instead the floss is tensioned after tying. In addition the collapsible arm provides a compact arrangement.

Furthermore the device provides a housing for a roll of dental floss, so that floss may be dispensed by the device for a considerable time without needing a refill.

Various modifications may be made to the embodiment described above. For example only one tooth 20 may be provided on the arm 18. In this case, arm 1 8 is first extended by a desired amount and then the floss is secured to the cleats as above; arm 18 is then further extended until nose 30 notches behind the tooth.

Various alternative means may be used instead of cleats 13, 1 9 to secure the ends of the thread.

For example an open-ended slot may be used in the end of arm 18 or in body portion 11.

Preferably the sides of the slot are sufficiently flexible to grip the thread. The inside surfaces of the slot are also preferably roughened to provide an improved grip. Alternatively spring clips of thin metal may be used to grip the ends of the thread.

A further way in which the ends of the thread may be secured is shown in Fig. 8. In this modification, cleats 13, 1 9 are replaced by screws 43, 49. The screws are preferably moulded in acetal or similar thermoplastic material and have heavily knurled heads for ease of grip, and a low pitch thread. The threaded iength is such that a user of the device is unlikely ever to completely unscrew and remove the screws from their locations, and it is impossible for them to accidentally become separated from the device.

In use screws 43 and 49 are unscrewed sufficiently to create respective slots 44, 48 between their heads and the adjacent parts of the device. The dental floss is then wound round each screw and the screw is tightened so as to grip the floss between the head of the screw and the adjacent part of the device. Tension is then applied to the thread as described previously.

Aithough in the arrangement shown the arm 18 slides relative to the body 11, the arm can alternatively be rotatably mounted on the body.

The device may be used with threads other than dental floss; for example it could be used to support a length of wire.

Claims (11)

1. A device for supporting a thread comprising a body member, which has a first attachment point for a thread, an arm member, which has a second attachment point for a thread and which is movable relative to said body member to vary the separation of said first and second attachment points, and a means for locking said arm member to said body member in a desired relative position.

2. A device according to claim 1, wherein the locking means can lock the arm member in a plurality of relative positions.

3. A device according to claim 1 or 2, wherein the locking means comprises a nose portion provided on the body member which is resiliently biassed to engage with one or more teeth provided on the arm member.

4. A device according to claim 3, wherein the nose portion may be disengaged from the teeth by means of a button which is manually-operable from outside the body member.

5. A device according to any preceding claim wherein the arm member can be substantially completely retracted within the body member.

6. A device according to any preceding claim wherein the body member is provided with means for cutting the thread.

7. A device according to any preceding claim wherein each attachment point comprises a cleat member.

8. A device according to any one of claims 1 to 6 wherein each attachment point comprises a screw member.

9. A device according to any preceding claim wherein the body member includes a housing for storing the thread to be used, and an opening is provided in the body member to permit dispensing of stored thread.

1 0. A device for supporting a thread substantially as herein described with reference to Figs 1 to 7 of the accompanying drawings.

11. A device for supporting a thread substantially as herein described with reference to Figs 1 to 7 as modified by Fig 8 of the accompanying drawings.