Background to the Invention The closest prior art to the present application is the applicant's own prior patent application GB0219120.3 (PCT/GB2003/003563). This prior application deals exclusively with hand-held chamfering tools and will not have been published by the filing date of the present application and on that basis its effect on this application is limited but is mentioned here as useful background.

The next closest prior art concerns power driven tools such as those disclosed in US4114484 and US4840096. Both of these prior art documents introduce complex multi- part power tools incorporating such elements as clamps, integrated motor and cutting head, remote control apparatus etc.

One of the objectives of the present invention is to introduce a tool which is separate from expensive and complex power driving machinery. One particular objective of the present

invention is to provide a tool which may be selectively employed for either manual chamfering or mounting in a common wireless rotary driver.

Summary of the Invention In a first broad aspect, the invention provides a rotary tool for chamfering the end regions of pipes or the like, the tool consisting of a collar, one surface of which incorporates abrasive means and allows mating engagement when in use, with a corresponding article destined for chamfering, and a spigot, central to the collar, incorporating means facilitating gripping of the spigot by a drill chuck, characterised by the feature that the tool comprises just the collar, the spigot and the necessary radial webs connecting the one to the other.

This is particularly advantageous because it is more practical to use than the complex prior art discussed above. It is particularly practical when destined to be used in confined spaces. It is also particularly low cost to manufacture and adaptable to be used with currently available drills or other machinery available on today's work sites.

In a second broad aspect, the invention provides a rotary tool for chamfering the end regions of pipes or the like, the tool consisting of a collar, one surface of which incorporates abrasive means and allows mating engagement, when in use, with a corresponding article destined for chamfering, and a spigot, central to the collar, incorporating means for facilitating gripping of the spigot by a drill chuck and radial webs connecting the spigot to the collar, characterised by the feature that the tool further comprises a connector which mates, in use, with a portion of said spigot and is itself of greater diameter than the spigot.

This configuration is particularly advantageous because it would allow the use of a relatively compact spigot which would have particular benefits for example, when the connector is removed from the tool and the tool is selected for manual chamfering.

In a further subsidiary aspect, the radial webs merge into a single piece covering the entire inner diameter area of the tool.

This would be particularly advantageous in terms of the tool's strength and durability. It would also create a barrier for the swarf which may be caused to exit the tool at its far end rather than exiting the tool in the direction of the user.

In a further subsidiary aspect, the radial webs consist of three arms located substantially 120° apart.

This would ideally combine structural strength and accessibility to the tool during use for say cleaning purposes.

In a further subsidiary aspect, the tool is made out of a sheet of material specifically adapted to be folded into a tool according to any preceding aspects.

This would allow the tool to be sold in flat-pack form which may be ideal where the tool is a disposable item.

In a further subsidiary aspect, the tool incorporates means for facilitating gripping about the periphery of the collar and/or about a handle stretching across said collar so that the rotation of the operator's hand translates directly into the rotation of the collar.

This combination of features would allow the tool to be selectively used in an improved manner either with a drill chuck or manually for certain chamfering operations.

Brief Description of the Figures Figure 1 shows a side elevation of a first embodiment of the invention.

Figure 2 shows an end elevation of a second embodiment of the invention.

Figure 3 shows a third embodiment of the invention.

Figure 4 shows an end elevation of a fourth embodiment of the invention.

Figures 5 show a fifth embodiment of the invention.

Figure 6 shows a perspective view of a sixth embodiment of the invention.

Detailed Description of the Figures Figure 1 shows a rotary tool 1 comprising a collar 2 with an inner abrasive means (not illustrated in the figure) and a radial web 3 extending across the diameter of the rotary tool 1. At a central region of web 3 a spigot 4 with multiple faces has been provided to allow it to be held by a drill chuck.

In this specification the term'central'when referring to the location of the spigot is to be interpreted broadly as generally central but allowing a degree of eccentricity. If spigot 4 were located in a slight centric position it is likely that adequate chamfering could be achieved of the end of a pipe particularly when the pipe is itself flexible.

Furthermore, the term'spigot'is also to be interpreted broadly and extends to projections which are either solid or incorporate hollow portions and also extends generally to any means capable of releasably engaging a drill chuck to allow the drill to drive the rotary motion of the tool.

On the outer surface of collar 2, there are provided high friction finger engaging portions such as that referenced 5 which could allow a user, should he/she desire, to manually operate the tool.

Figure 2 shows a further rotary tool 6 with a collar 7 comprising abrasive portions such as that referenced 8 located on the outside of the collar. On the inside of the collar there are provided a number of recesses 9 so sized to receive the end regions of the operator's fingers should he/she desire to operate the tool manually. A web 10 stretches across the collar with a receiving means or spigot 11 for receiving a mating part of a drill to allow the transmission of rotation from the drill to the tool.

Figure 3 shows a further tool referenced 12. Incorporating a recessed spigot 13 designed to mate with projection 14 of a connector 15. The diameter of the connector 15 may be selected as larger than the diameter of recessed spigot 13 in order to accommodate a variety of drill chucks or other power driving appropriate devices.

Figure 4 shows a tool 16 with a web generally referenced 17 formed of three arms 18,19 and 20. The arms are located at 120° apart from one another.

Figure 5b shows a sheet of material 21 with an abrasive side 22. The device may be folded to form the tool as shown in Figure 5a. Attachment means 23 and 24 are provided to attach the extremities of the sheet of material to form a collar as shown in Figure 5a.

Three arms 25,26 and 27 may be folded inwardly and attached together at their extremities to form the necessary radial webs of the rotary tool. When these arms are joined together a spigot 28 is formed and may be used to co-operate with the chuck of a drill.

Figure 6 shows a tool 29 with a cylindrical spigot 30 and a single web 31 stretching across the entire inner diameter area of the collar 32 of tool 29.