WO1991019436A1

WO1991019436A1 - Nail cutting device

Info

Publication number: WO1991019436A1
Application number: PCT/GB1991/000901
Authority: WO
Inventors: Kwok Hung Leung
Original assignee: Kwok Hung Leung
Priority date: 1990-06-14
Filing date: 1991-06-05
Publication date: 1991-12-26
Also published as: AU7988891A

Abstract

There is disclosed a nail cutting device comprising a tubular casing (16) having a slot-like opening (18) in the wall thereof sized to permit entry of the edge of a human nail, blade means (15) rotatable within the casing (16) which cooperates with a sharpened edge to said opening to sever any portion of nail extended through the opening.

Description

NAIL CUTTING DEVICE

This invention relates to a cutting device for human nails.

Conventional methods of nail cutting involve the use of nail scissors or nail clippers. Neither can be operated with equal ease ambidextrously. Both are difficult to operate, if at all, by a weak hand, as of an elderley person for example, produce a course finish requiring if desired subsequent use of a nail file and can cause damage to soft tissue adjacent the nail. A further disadvantage is the often uncontrolled flight of clipped portions of nail which have to be gathered after the cutting operation.

It is an object of the present invention to provide a nail cutting device which overcomes, at least to some extent, the disadvantages aforesaid.

According to the present invention there is provided a nail cutting device comprising a tubular casing having a slot-like opening in the wall thereof sized to permit entry of the edge of a human nail, blade means rotatable within the casing which cooperates with a sharpened edge to said opening to sever any portion of nail extended through the opening. The opening may extend generally parallel with the longitudinal axis of the casing.

The casing may be circular.

The opening may extend through an end of the wall of the casing.

Both side edges of the opening may be sharpened.

The blade means may comprise an inner circular tube having a generally axially extending slot therein, at least one edge of the slot being sharpened.

Both side edges of the slot may be sharpened.

The side edges of the slot in the circular tube may diverge outwardly from one another towards one end of the tube.

The slot may extend through an end of the wall of the tube.

The blade means may comprise a rod having at least one helical groove on its peripheral surface, at least one edge of the groove being sharpened. The device may have a handle to which the outer tube is secured and incorporating drive means for rotating the blade means.

A finger rest may be connected with the handle to aid the introduction of a nail to be cut into the opening.

The drive means may comprise an electrically powered motor connected with the blade means by gearing.

The blade means may be drivable at sufficiently high speed that a sweeping arcuate movement of the edge of the nail through the opening in the casing results in such multiplicity of cuts as to give a smooth finish to the cut edge.

The drive means may additionally drive a fan to blow air or suck air in through the bore of the casing to collect or expel nail clippings therefrom.

The motor drive may be reversible.

The invention will be further apparent from the following description, with reference to the several figures of the accompanying drawings, which show, by way of example only, two forms of nail cutting device embodying same. Of the drawings :-

Figure 1 shows a partially cut-away perspective view of the first form of nail cutting device;

Figure 2 shows an exploded perspective view of the principal parts of the nail cutting device of Figure 1;

Figure 3 shows on an enlarged scale a side view of the tubular casing of the device of Figure 1;

Figure 4 shows on an enlarged scale a side view of blade means of the device of Figure 1;

Figure 5 shows a side view of a modified casing;

Figure 6 shows a side view of a modified blade means for use with the casing of Figure 5; and

Figure 7 shows a cross-section through the blade means on the line VII-VII of Figure 6. Referring firstly to Figures 1 and 2 it will be seen that the nail cutting device comprises a handle generally indicated at 10 which houses batteries 11, a DC motor 12 and a planetary reduction gearing system generally indicated at 13 as well as an on/off switch 14 for the motor 12 which can be operated to drive the motor in either direction.

The device includes a set of cutting blades comprising an inner circular tube 15 and an outer circular tube or casing 16. Both tubes are of steel. The inner tube 15 which has a sliding fit within the outer tube 16 can be rotated therein at a high speed by the motor 12 via the gearing system 13. The outer tube

16 is fixed relative to the handle 10.

From the open free ends of the inner and outer tubes 15 and 16 extend generally axially aligned slots

17 and 18 respectively part-way into the lengths of the tubes.

The edges of the slot 17 diverge outwardly from one another towards the free end of the tube 15, and both are sharpened.

The edges of the slot 18 are parallel with the longitudinal axis of the tube, and again both are sharpened. The slot 18 in the outer tube 16 is sized to permit entry of the edge of a human nail but not any adjacent soft tissue. Typically its length L (see Figure 3) will be 11.5 mm and its width between 1 mm and 2 mm, it being understood that different sizes may be provided and suited for different thicknesses of nail. The wall of the outer tube will have a typical thickness of 0.25 mm.

The slot 17 in the inner tube 15 lies within that portion of the tube 16 provided with the slot 18 and has a length of 14 mm and a width of 3.5 mm tapering to 0.8 mm.

In use the device is held in one hand, and the motor 12 operated in such direction that as the inner tube 15 is rotated the edges of the slot 17 move downwardly over the edges of the slot 18. Each nail on the other hand opposite that holding the device is introduced through the slot 18 in turn and swept therethrough with an arcuate movement. The inner tube rotates at sufficiently high speed to produce a sufficient multiplicity of adjacent cuts as to give a smooth finish to the trimmed edge.

A finger rest 20 is provided adjacent the cutting blades to facilitate the cutting operation.

It will be understood that no manual force is required to effect the cutting action, which is both painless and comfortable.

As shown in Figure 5 in a modified embodiment the opening 18 in the casing 16 is in the form of a window with one sharpened edge.

In this embodiment the blade means comprises a rod 30 having a plurality of helical grooves 31 on its periphery, one edge of each groove being sharpened to cooperate with the sharpened edge of the opening 18.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof as defined by the appended claims.

Thus, for example, the device need not be hand held. It could be table mounted, in which event in the case of the first described embodiment the motor need drive the inner tube in one direction only and one edge only of each slot need be sharpened.

Again, for example, the motor may drive a fan to blow air or suck air in through the bore of the casing to collect or expel nail clippings therefrom, perhaps into a collection compartment.

Claims

CLAI S

1. A nail cutting device comprising a tubular casing having a slot-like opening in the wall thereof sized to permit entry of the edge of a human nail, blade means rotatable within the casing which cooperates with a sharpened edge to said opening to sever any portion of nail extended through the opening.

2. A device according to claim 1, wherein the opening extends generally parallel with the longitudinal axis of the casing.

3. A device according to claim 1 or claim 2, wherein the casing is circular.

4. A device according to any one of claims 1-3, wherein the opening extends through an end of the wall of the casing.

5. A device according to any one of claims 1-3 wherein the opening is in the form of a window in the wall of the casing.

6. A device according to any one of claims 1-5, wherein one or both side edges of the opening are sharpened.

7. A device according to any preceding claim, wherein the blade means comprises an inner circular tube having a generally axially extending slot therein, at least one edge of the slot being sharpened.

8. A device according to claim 7, wherein both side edges of the slot are sharpened.

9. A device according to claim 7 or claim 8, wherein the side edges of the slot in the circular tube diverge outwardly from one another towards one end of the tube.

10. A device according to any one of claims 7-9, wherein the slot extends through an end of the wall of the tube.

11. A device according to any one of claims 1-6, wherein the blade means comprises a rod having at least one helical groove on its peripheral surface, at least one edge of the groove being sharpened.

12. A device according to any preceding claim, having a handle to which the outer tube is secured and incorporating drive means for rotating the blade means.

13. A device according to claim 12 having a finger rest connected with the handle to aid the introduction of a nail to be cut into the opening.

14. A device according to claim 12 or claim 13, wherein the drive means comprises an electrically powered motor connected with the blade means by gearing.

15. A device according to any one of claims 12-14, wherein the blade means are drivable at sufficiently high speed that a sweeping arcuate movement of the edge of the nail through the opening in the casing results in such multiplicity of cuts as to give a smooth finish to the cut edge.

16. A device according to any one of claims 12-15, wherein the drive means additionally drives a fan to blow air or suck air in through the bore of the casing to collect or expel nail clippings therefrom.

17. A device according to claim 10, wherein the motor drive is reversible.