TECHNICAL FIELD

A tool for chamfering is disclosed, and particularly, although not exclusively, a tool for chamfering the edges of plastic pipes and sheets.

BACKGROUND ART

Recent improvements in construction materials and techniques have given rise to the widespread use of plastic piping and plastic sheets. Plastic piping has proven especially useful as a conduit for the protection of underground electrical wiring and as drainpipe for use in plumbing .

In many applications, such pipe is formed in predetermined lengths and placed end-to-end and a connector is placed over the ends to join the pipes together. Alternatively, two or more pipes may be joined together by means of widening or belling the end or using rubber ring joints on one pipe and chamfering the end of another pipe . Hence chamfering the ends of pipes can be used to allow one pipe to be inserted into another or to allow a pipe to be inserted into a connector.

Further, if desired, a pipe end may be provided with an internal chamfer. If the pipe is to be used as protection for electrical cable, the internal surface of the pipe may be chamfered to prevent there being sharp edges that may allow the cable insulation to be frayed, torn or broken as it is being threaded through the pipe.

Pipes composed of alternate materials such as metal or concrete may also require chamfering.

Previous chamfer tools generally comprise a holder and a cutting element angularly offset to the holder.

SUMMARY OF THE DISCLOSURE A chamfer tool for chamfering an article, the tool comprising a cutting element adapted for attaching to a drive, and at least one guide element adapted such that the chamfer tool can be mounted to the edge of the article and moved there along.

In one form the cutting element is rotatable.

In one form the cutting element is adapted for attaching with a drill.

In one form the cutting element comprises a plurality of blades positioned to form an inverted cone shape.

In one form each guide element comprises at least one, and typically three, downwardly extending guide shafts, each downwardly extending guide shaft having a rolling element attached thereto .

In one form the rolling element comprises a cylindrical roller adapted in use to be in rolling contact with the article.

In one form the three guide elements are positioned such that in use one guide element is positioned on one side of the article adjacent to the edge and the other guide element is positioned on the other side of the article adjacent to the edge.

In one form the article is a pipe and the sides correspond to inside and outside surfaces of the pipe.

In one form the or each guide element is movable in relation to the cutting element. In one form each guide element is movable in relation to any other guide element.

In one form the chamfer tool further comprises a mounting plate to which the cutting element and the or each guide element is attached.

BRIEF DESCRIPTION OF THE DRAWINGS

It is convenient to hereinafter describe an embodiment of a chamfer tool with reference to the accompanying drawings. It is to be appreciated that the particularity of the drawings and the related descriptions is to be understood as not superseding the generality of the preceding broad description of the chamfer tool.

In the drawings:

Figure 1 is a top perspective view of a chamfer tool and pipe ;

Figure 2 is a side perspective view of a chamfer tool;

Figure 3 is a front elevation view of the chamfer tool of Figure 2 ;

Figure 4 is a side elevation view of the chamfer tool of

Figure 2.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS Referring to the figures, disclosed is a chamfer tool 1 for chamfering the edges of a plastic pipe 2 or other chamferable article.

The chamfer tool 1 comprises a cutting element 4 and driveshaft 5 extending through a mounting plate 3. The cutting element 4 and driveshaft 5 are attached to the mounting plate 3 by means of a spindle assembly 6. The cutting element 4 and driveshaft 5 are attached to one another and are rotatable. When the cutting element 4 is brought into contact with the edges of a pipe or sheet, the rotation of the cutting element 4 allows the cutting element 4 to chamfer the edges of the pipe or sheet .

The cutting element 4 is shaped as an inverted cone. In one form the cutting element 4 comprises a plurality of blades (not illustrated) positioned to form an inverted cone. Typically the cutting element 4 comprises between two and ten blades and more typically the cutting element comprises six blades positioned to form an inverted cone.

The cutting element 4 is replaceable so as to provide varying angles of chamfering. A shorter inverted cone will allow for a shallower angle of chamfering while a longer inverted cone will result in a steeper angle of chamfering. The cutting element 4 is preset at an angle appropriate for chamfering. In one embodiment this angle is between 12° and 15°.

The driveshaft 5 is adapted to allow attachment of the chamfer tool 1 to a drill or other motor (not illustrated) . The drill or other motor can be attached with the driveshaft 5 to rotate the cutting element 4. The driveshaft 5 extends through the spindle assembly 6 which is attached to the mounting plate 3. it can be seen that this allows a user to utilise the chamfer tool with ordinary tools commonly held.

Three guide elements 8 are attached with the mounting plate 3. The guide elements 8 comprise a rolling element 9 and a guide shaft 10. The guide shaft 10 extends through the mounting plate 3 and the rolling element 9 such that the guide element 8 is attached with the mounting plate 3. The rolling element 9 comprises a cylindrical roller adapted such that in use the cylindrical roller is in rolling contact with the article to be chamfered.

The guide elements 8 are positioned such that in use on a pipe 2 one central guide element 8' is positioned inside the pipe 2 and two guide elements 8 are positioned outside the pipe 2. This allows the chamfer tool 1 to be mounted on the pipe 2 and rolled there around.

The guide elements 8 are movable in relation to one another by a guide element adjustment means 11. The guide element adjustment means 11 can comprise a screw or a handle which allows the guide elements 8 to be moved in relation to each other.

As the plastic pipe 2 is inserted between the guide elements 8 for chamfering, the guide element adjustment means 11 allow for the chamfer tool 1 to be mounted upon pipes of varying diameters -

The central guide element 8' is also adjustable in relation to the cutting element 4 by a central guide element adjustment means 12. This allows for varying thickness of the wall of plastic pipe 2 or thickness of plastic sheet. The central guide element adjustment means

12 comprises either a screw or a handle or any other appropriate adjustment means.

A support bracket 13 extends from the mounting plate 3 and supports the central guide element 8'. This allows for greater stability of the chamfer tool 1.

In use, the guide elements 8 are adjusted to best contain the diameter of the plastic pipe 2. The central guide element 8' is adjusted to allow for the thickness of the plastic pipe 2. The guide elements 8 are adjusted by means of loosening the guide element adjustment means 11 and 12 and moving the guide elements 8 to the required position. The adjustment means 11 and 12 can then be tightened to maintain the guide elements 8 in position in relation to one another and in relation to the cutting element 4. The chamfer tool 1 can then be mounted upon the pipe 2.

The driveshaft 5 can then be attached to a drill or other motor (not illustrated) . When the chamfer tool 1 is positioned over the pipe 2 the cutting element 4 is in position to chamfer the edges of the plastic pipe 2. When the drill or motor is turned on the cutting element 4 rotates to chamfer the edges of the pipe 2. The chamfer tool 1 can then be moved circumferentially about the plastic pipe 2. In doing this, the rolling elements 9 of the guide elements 8 are in rolling contact with the pipe allowing for movement of the guide elements 8 about the plastic pipe 2.

The cutting element 4 can be positioned inside or outside the plastic pipe so as to allow for an internal or external chamfer .

In the claims which follow and in the preceding summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including" , that is the features specified may be associated with further features in various embodiments of the invention.

Variations and/or modifications may be made to the parts previously defined without departing from the broad spirit or ambit of the chamfer tool .