WO2004007214A1

WO2004007214A1 - A groove-forming tool

Info

Publication number: WO2004007214A1
Application number: PCT/EP2003/007526
Authority: WO
Inventors: Gerard Mcerlean
Original assignee: Gerard Mcerlean
Priority date: 2002-07-10
Filing date: 2003-07-10
Publication date: 2004-01-22
Also published as: AU2003254336A1; GB0215863D0

Abstract

A tool comprising a cutter (14) and a jig (12) shaped to define a channel (17). The jig is shaped and dimensioned to seat the cutter such that a portion of the cutter projects through the channel. When seated on he jig, the cutter is movable along the channel. The tool may be used to form grooves in a working surface comprising wet or semi-set material such as plaster, putty or cement in order to produce a decorative effect.

Description

A GROOVE-FORMING TOOL

FIELD OF THE INVENTION

The present invention relates to a groove-forming tool, especially, but not exclusively, for forming decorative grooves in plaster.

BACKGROUND TO THE INVENTION

When plastering a building, especially a house, it is often desired to give a decorative appearance to plastered surfaces. In particular, it is often desired to give external plastered surfaces a quoined appearance. It is known to use a plastering tool to cut or form a groove in semi-set plaster in order to give such an appearance. For example, a thin blade or the like is generally used for scoring simulated joint lines on plaster to produce the ornamental finish of quoining. A problem with conventional plastering tools is that, in order to achieve a neat, reproducible finish, a significant amount of time and effort must be spent to ensure a constant depth of cut, and that the grooves cut in the plaster are both straight and parallel to one another.

SUMMARY OF THE INVENTION

Accordingly, a first aspect of the invention provides a tool comprising a cutter; and a jig shaped to define a channel, the jig being shaped and dimensioned to seat the cutter such that a portion of the cutter projects through the channel, and wherein, when seated on he jig, the cutter is movable along the channel.

Preferably, the jig is shaped to define an elongate rectilinear channel.

Preferably, the channel is defined by opposing side faces of the jig, the side faces being inclined with respect to the plane of the channel and converging with one another in a direction towards the channel. More preferably, the cutter has side walls correspondingly inclined with the channel side faces.

Preferably, the cutter comprises- a cutting head of substantially triangular cross-section, the cutting head having a leading surface which projects through the channel when the cutter is seated on the jig. More preferably, the leading surface comprises a substantially rounded leading edge.

Preferably, the jig comprises at least two spaced apart limbs, between which limbs the channel is defined.

Preferably, the jig is arranged to allow the width of the channel to be adjusted. More preferably, at least one of said limbs is moveable towards or away from the other of said limbs. Further preferably, respective adjacent ends of the limbs are connected together by a respective end piece, each end piece being provided with at least one slot for receiving at least one fastening member for fixing one or more limbs to the respective end piece. Preferably, the cutter includes a forward face which acutely inclined with respect to the, in use, underside of the cutter.

Preferably, the jig is provided with a folding mechanism enabling the jig to be operable between an unfolded state, in which the jig is substantially coplanar, and one or more folded states, in which respective portions of the jig on either side of the folding mechanism are non-coplanar .

A second aspect of the invention provides a j ig for use with the tool according to the first aspect of the invention.

Further advantageous aspects of the invention will become apparent to those ordinarily skilled in the art upon review of the following description of a specific embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the present invention will now be described by way of example and with reference to the accompanying drawings in which:

Figure la is a perspective view of an embodiment; of a cutter forming part of a tool of the present invention;

Figure lb is a perspective view of an embodiment of a jig forming part of the tool; Figure 2 is a perspective view of the tool, in use, cutting a groove from a plastered surface;

Figure 3 is a sectioned side elevation of the cutter located within the jig;

Figure 4a is cross-sectional end view of the cutter located within the jig;

Figure 4b is a view of the jig of Figure 4a in a first operational state; and

Figure 4c is a view of the jig of Figure 4a in a second operational state.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to the accompanying drawings, there is illustrated, generally indicated as 10, a preferred embodiment of a tool, according to one aspect of the invention, for forming a groove 42 in formable material 41. The tool may be used with any working surface comprising formable material, especially, but not exclusively, wet or semi-set plaster, putty, or cement. In the present embodiment, the formable material 41 is assumed to comprise wet or semi-set plaster.

The tool 10 comprises a jig 12 and a cutter 14. The purpose of the cutter 14 is to cut or form grooves or channels in the plaster 41. To this end, the cutter comprises a cutting head 21 which has a leading surface or edge 23 for engagement with the plaster 41. The leading edge 23 is depicted as being of substantially V-shaped transverse cross-section and, consequently, grooves formed by the cutting head 21 are of substantially V-shaped transverse cross-section. The apex of the V-shape is preferably rounded (as shown) rather than being sharp. In alternative embodiments (not shown) the transverse cross-section of the cutting head 21, and in particular the leading edge 23 may take any desired shape, for example rounded, semi-circular or rectangular.

The jig 12 comprises a body 13 shaped to define an elongate aperture or channel 17. In the preferred embodiment, the jig 12 comprises two substantially parallel, spaced-apart limbs 15 between which the channel 17 is defined. Most commonly, it is desired to form straight-edged, or rectilinear, grooves 42 and, to this end, it is preferred that the respective opposing faces 16 of the limbs 15 are substantially straight or rectilinear so that the channel 17 is substantially straight-sided or rectilinear. Advantageously, the limbs 15 are substantially flat or planar at least on their, in use, underside.

The relative shape and dimensions of the channel 17 and the cutter 14 is such that the cutting head 21 may be seated, in use, in the channel 17 so that a portion of the cutting head 21, and at least the cutting edge 23, projects through the channel 17, as shown, for example, in Figure 4a. Further, when the cutter 14 is seated in the channel 17, the relative lengths of the cutting head 21 and the channel 17, in a direction parallel with the longitudinal axis of the channel 17, are such that the cutter 14 is slidably movable along the channel 17 in said longitudinal direction (indicated by arrow A in Figure 2) .

The respective opposing side faces 16 of limbs 15 are preferably inclined, or obliquely disposed, with respect to the plane in which channel 17 is disposed such that the two faces 16 converge in a direction towards the channel 17. This facilitates the seating of cutter 14 in the channel 17 in the manner described above, particularly where the cutting head 21 is substantially V-shaped in transverse cross-section. In this connection, it is preferred that side faces 16 are inclined at an angle substantially corresponding to the angle of inclination of the side- faces 28 of the cutter 14. In alternative embodiments (not illustrated) the side faces 16 may take alternative shapes and/or inclinations to match or suit the shape of the portion of cutter to be seated therebetween. The cutter need not necessarily engage with the opposing sides of the channel and may alternatively be provided with a flange for engaging with the in-use outer faces of the limbs.

In use, the jig 12 is placed onto a working surface, for example a layer of plaster 41 on an external wall 40, as shown in Figure 2. Advantageously, the jig 12 is positioned so that a portion overhangs from the working surface 41 by an amount sufficient to allow the cutter 14 to be seated in the overhanging portion of the channel 17 (see Figure 2) . A user (not shown) then slides the cutter 14 along the channel 17 across the plaster 41 thereby forming a groove 42 in the plaster 41. The size and shape of the groove 42 is determined by the size and shape of the portion of the cutting head 21 that protrudes through the channel 17 (as may best be seen in Figure 4a) .

The limbs 15 may be formed from any suitable material, preferably lightweight material such as wood or box section aluminium. In cases where the limbs 15 are formed from a soft, or non-hard-wearing material (e.g. wood) , it is preferred that the respective side face 16 of each limb 15 is provided with a durable strip 19 in order to save wear on the side faces 16. Conveniently, the strips 19 are formed from metal such as aluminium or steel with a relatively smooth or polished surface to help reduce friction between the cutter 14 and the jig 12. Each strip 19 may be secured to the respective side face 16 by any suitable means, for example rivets 18 or glue.

One or both of the limbs 15 may carry measurement graduations (not shown) and/or a spirit level (not shown) .

In the preferred embodiment, one or both of the limbs 15 is movable towards and away from the other so that the width of the channel 17 may be varied. Not only does this allow grooves of varying width to be formed but also grooves of varying depth.

This may be achieved in any suitable manner. By way of example, and with reference in particular to Figure 3, the respective adjacent ends of each limb 15 are joined together by a respective end piece 20. Each end piece 20 is provided with one or more slots 22 (four shown by way of example) , at least one respective slot 22 being in register with the end of each limb 15. The end of each limb 15 is provided with one or more apertures (not visible) for receiving a respective screw 24. Before the tool 10 is used, the limbs 15 are generally positioned at a desired distance apart with the respective apertures in the ends of the limbs 15 being in register with a respective slot 22. A respective screw 24 is then used to fasten the limbs 15 to the end pieces 20 as shown in Figure lb to define a first use state for the jig 12. The limbs 15 are movable from the first state to another use state by unscrewing the screws 24 and moving one or both of the limbs 15 towards or away from the other. The extent to which the limbs 15 may be moved is determined by the length of the slots 22. Once in another use state, the limbs 15 are retained in that position by re-screwing the screws 24. Movement of the limbs 15 between a first and a second use state is shown clearly in Figures 4b and 4c respectively. It will be understood that the limbs 15 are movable by any distance intermediate the two extremes shown in Figures 4b and 4c and may therefore adopt a plurality of use states. Movement of the limbs 15 in the manner described above enables the width of the channel 17 to be adjusted. In the illustrated embodiment, the shape and configuration of cutter 14 and the sides 16 of the channel 17 cause the depth of grooves 42 to be varied with the width although a different cutter (not shown) could be used if it were desired to maintain the groove depth.

Referring now to Figure la, the side walls 28 of the preferred cutter 14 are shown tapered inwardly towards one another (in a direction towards the leading edge 23) such that the cutter 14 forms a substantially triangular prism. The opposed side faces 16 of the limbs 15 are inclined at substantially the same angle as the respective side walls 28 of the cutter 14, thereby establishing a secure fit between the cutter 14 and the jig 12, as shown in Figure 4a. The cutter 14 is also provided with a handle 30 which projects from a top surface 32 thereof, and a forward face 26 located at one end of the cutter 14 intermediate the top surface 32 and the side walls 28.

The forward face 26 is preferably tapered away from the top surface 32 of the cutter 14 (in a direction towards the leading edge 23) such as to provide a rake angle X as shown in Figure 3. In use, the rake angle X enables the plaster (or other material as applicable) to be easily removed when forming the grooves 42. As the cutter 14 proceeds along the channel 17, the rake angle X causes plaster to be forced upwardly along the forward face 26 towards the handle 30. The rake angle X helps prevent any blocking of the channel 17 by excesses of plaster 41. By way of example, a rake angle in the range 20° to 30° is found to be particularly suitable. The cutter face (not visible) oppositely disposed to the forward face 26 of the cutter 14 may also be inclined to provide a rake angle (not shown) .

In an alternative embodiment (not illustrated) the jig is provided with a hinge, or other folding mechanism, arranged to allow the jig to be folded or bent about the hinge. The hinge may be arranged to adopt an unfolded state, in which the jig is substantially planar in shape (as shown in Figures 1 to 4), and one or more folded states in which one portion of the jig is angled with respect to another portion of the jig. In the, or each, folded state, the jig may be used to form grooves in a correspondingly non-planar working surface. For example, in a simple embodiment, a hinge, preferably a locking hinge, is provided at, say, the mid-point of the jig and is arranged to hold the jig in the unfolded state or a single folded state in which the two hinged portions of the jig are disposed substantially at 90° to one another. In this folded state, the tool may be used to form grooves around, for example, a right angled corner of a building. More than one hinge may be provided if it is desired to fold the jig at more than one location.

The cutter 14 is not limited to being in the shape of a triangular prism. For example, the cutter 14 may comprise any other suitable shape which enables at least a side wall thereof to provide a secure fit with the side faces 16 of the limbs 15.

It will be apparent form the foregoing description of a specific embodiment, that the groove forming tool enables a user to form grooves that are consistent, i.e. repeatable, and are of a desired width, depth and shape depending on the state of the jib and on the size and shape of the cutter. The tool is particularly, but not exclusively, suited for use in forming a quoin- effect pattern on a working surface. The invention is not limited to the embodiments described herein which may be modified or varied without departing from the scope of the invention.

Claims

CLAIMS :

1. A tool comprising a cutter; and a jig shaped to define a channel, the jig being shaped and dimensioned to seat the cutter such that a portion of the cutter projects through the channel, and wherein, when seated on he jig, the cutter is movable along the channel.

2. A tool as claimed in Claim 1, wherein the jig is shaped to define an elongate rectilinear channel.

3. A tool as claimed in Claim 1 or Claim 2, wherein the channel is defined by opposing side faces of the jig, the side faces being inclined with respect to the plane of the channel and converging with one another in a direction towards the channel.

4. A tool as claimed in Claim 3, wherein the cutter has side walls correspondingly inclined with the channel side faces.

5. A tool as claimed in any preceding claim, wherein the cutter comprises a cutting head of substantially triangular cross-section, the cutting head having a leading surface which projects through the channel when the cutter is seated on the jig.

6. A tool as claimed in Claim 5, wherein the leading surface comprises a substantially rounded leading edge.

7. A tool as claimed in any preceding claim, wherein the jig comprises at least two spaced apart limbs, between which limbs the channel is defined.

8. A tool as claimed in any preceding claim, wherein the jig is arranged to allow the width of the channel to be adjusted.

9. A tool as claimed in Claim 8 when dependent on Claim 7, in which at least one of said limbs is moveable towards or away from the other of said limbs .

10. A tool as claimed in Claim 9, wherein respective adjacent ends of the limbs are connected together by a respective end piece, each end piece being provided with at least one slot for receiving at least one fastening member for fixing one or more limbs to the respective end piece.

11. A tool as claimed in any preceding claim, wherein the cutter includes a forward face which acutely inclined with respect to the, in use, underside of the cutter.

12. A tool as claimed in any preceding claim, wherein the jig is provided with a folding mechanism enabling the jig to be operable between an unfolded state, in which the jig is substantially coplanar, and one or more folded states, in which respective portions of the jig on either side of the folding mechanism are non- coplana .

13. A jig for use with the tool according to Claim 1.