GB2403923A

GB2403923A - Jig assembly

Info

Publication number: GB2403923A
Application number: GB0316689A
Authority: GB
Inventors: Terry John Claydon
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-07-16
Filing date: 2003-07-16
Publication date: 2005-01-19
Anticipated expiration: 2023-07-16
Also published as: GB2403923B; GB0523272D0; GB2420516A; GB0316689D0

Abstract

A jig assembly 1 for guiding a cutting tool comprises a jig body 3 having one or more guide surfaces 5a, 5b for guiding the cutting tool. The guide surfaces 5a, 5b are formed by a replaceable insert 13, which is detachably connected to the jig body 3. The provision of a replaceable insert 13 allows the guide surfaces 5a, 5b to be replaced when damaged or worn, without having to replace the whole jig assembly. According to another embodiment (see Figure 5 and 6, not shown), the guide surfaces 5a, 5b are formed by separate replaceable inserts 25a, 25b. The jig body 3 and replaceable insert 13 can be made from the same or different materials. The replaceable insert 13 can be more hardwearing and/or expensive than the jig body, or vice versa.

Description

1 2403923

JIG ASSEMBLY

Field of the invention

The invention relates to a jig assembly, and in particular, to a jig assembly for guiding a cutting tool such as a router.

Background of the invention

A jig is commonly used to guide a cutting tool such as a router over a workplace that needs to be cut accurately. In other words, the jig acts as a template having surfaces which guide the movement of the router over the workpiece, thereby removing the reliance on the skill and judgement of the user.

Figure 1 shows a known jig 1 that has been developed by the applicant for guiding a router during various cutting tasks associated with worktop surfaces, for example kitchen worktops. The jig 1 comprises a jig body 3 having various slots for guiding the router during the different cutting tasks. For example, the jig body 3 has a "postform joint" slot 5 that is shaped to cut an accurate joint between abutting worktop surfaces. The postform joint slot 5 has a first guide surface 5a for cutting a female joint on one worktop surface, and a second guide surface 5b for cutting a corresponding male joint on the other worktop surface.

In use, a guide bush located on the router is located in the postform joint slot 5, and held against either the first guide surface 5a or the second guide surface 5b, depending upon whether a female or male joint is being cut. r I

The jig shown in Figure 1 has a number of additional guide slots for performing other cutting tasks. For example, a corner radius slot 7 is provided for guiding the router when cutting a corner radius, and a curved peninsular slot 9 is provided for guiding the router when cutting a curved peninsular in a worktop surface.

The jig 1 also comprises a number of connecting bolt recess slots 11, for routing the recesses that receive the connecting bolts in the underside of worktop surfaces. Various positioning holes are also provided on the jig body 3, which assist with the positioning of the jig 1 to obtain an accurate cut.

It will be appreciated that the jig 1 must be manufactured to a high degree of accuracy, so that the router is in turn guided accurately over the workpiece.

This is particularly true for the postform joint slot 5 which is used for cutting the male and female joints on abutting worktop surfaces. The slightest flaw in the guide surfaces 5a, 5b of the postform joint slot 5 can destroy the desired "seamless" joint. This need for a jig body having accurate guide slots and positioning holes means that the jig is relatively expensive to manufacture.

As a consequence, jig assemblies such as those shown in Figure 1 are often used by tool hire companies for hiring out to do-it-yourself (DIY) enthusiasts. In other words, the cost of purchasing a relatively expensive item having only a limited use means that it is ideally suited for the tool hire industry. However, it has been found that hiring out jig assemblies often results in the jig being damaged. For example, a common problem is that users place the cutting bit of the router in the postform joint slot 5, rather than the guide bush as intended. This results in the guide i surfaces 5a, 5b of the jig being damaged, resulting in the whole jig assembly being destroyed.

In addition, although professional craftsmen using the jig are less likely to cause the type of damage mentioned above, it is still possible that the jig will be used for one particular cutting task more than the others, thus leading to one particular guide slot being worn or damaged prior to the others. This can result in the jig haying to be replaced at regular intervals, despite the jig body itself and many of the other guide slots being undamaged.

The aim of the present invention is to provide a jig assembly which does not suffer from the disadvantages mentioned above.

Summary of the invention

According to a first aspect of the present invention, there is provided a jig assembly for guiding a cutting tool, the jig assembly comprising a jig body having one or more guide surfaces for guiding the cutting tool, characterized in that at least a section of one guide surface is formed by a replaceable insert, the replaceable insert being detachably connected to the jig body.

According to another aspect of the present invention, there is provided a replaceable insert for use with a jig body, the replaceable insert being detachably connected to the jig body and forming with the jig body a jig assembly used for guiding a cutting tool, the replaceable insert comprising: a first section adapted to cooperate with a receiving section on the jig body; and r I a second section which acts as a guide surface for guiding the cutting tool.

According to another aspect of the present invention, there is provided a jig body for use with a replaceable insert, the replaceable insert being detachably connected to the jig body and forming with the jig body a jig assembly used for guiding a cutting tool, wherein I the jig body comprises at least one section adapted to receive a replaceable insert having a guide surface.

According to another aspect of the present invention, there is provided a jig assembly adapted for guiding a cutting tool over a worktop, the jig assembly comprising a jig body having one or more guide surfaces for guiding the cutting tool, characterized in that at least a section of one guide surface is formed by a replaceable insert, the replaceable insert being detachably connected to the jig body.

Brief description of the drawings

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 shows a jig assembly according to the prior art; Figure 2 shows a jig assembly having a replaceable insert according to a first embodiment of the invention; Figure 3 shows the replaceable insert of Figure 2 in I greater detail; r Figure 4 shows the jig assembly of Figure 2 in the assembled position; Figure 5 shows a jig assembly having a replaceable insert according to another aspect of the present invention; Figure 6 shows another view of the jig assembly of Figure 5; Figures 7a to 7b show replaceable inserts for use with the jig assembly of Figure 2.

Detailed description of a preferred embodiment of the invention Figure 2 shows a jig assembly 1 according to a first aspect of the present invention. As with Figure 1, the jig assembly 1 comprises a jig body 3 having one or more guide slots and a plurality of locating holes 23.

However, the jig assembly 1 according to the present invention comprises at least one section for receiving a replaceable insert 13. In the preferred embodiment, the section comprises an opening 12 for receiving the replaceable insert 13. The replaceable insert 13 is detachably connected to the jig body 3, and comprises at least one guide slot, for example a postform joint slot 5, for guiding a cutting tool.

Preferably, the replaceable insert 13 comprises a number of fixing holes 15 for use in connecting the replaceable insert 13 to the jig body 3. For example, the replaceable insert 13 may be fixed to the jig body 3 using screw fastenings (not shown) which locate with threaded bores 17 in the jig body 3. It will be appreciated, however, that the invention covers other r methods of detachably connecting the replaceable insert 13 to the jig body 3. For example, the replaceable insert 13 may be clipped or push fitted into the opening 12.

Preferably, the opening 12 in the jig body 3 has a recess 19 which mates with a complementary recess 21 (see Figure 3) in the replaceable insert 13. The provision of the matching recesses 19, 21, ensures that the replaceable insert 13 is accurately positioned in the jig body 3, thereby being correctly aligned with the positioning holes 23.

Figure 3 shows an alternative view of the replaceable insert 13 having a postform joint slot 5, and showing the recess 21 for mating with the corresponding recess 19 on the jig body 3 as described above.

Figure 4 shows the jig assembly 1 in the assembled position, in which the replaceable insert 13 is connected to the jig body 3.

The provision of a replaceable insert 13 has the advantage that, if the guide slot 5 becomes damaged or worn, the individual guide slot can be replaced without having to replace the whole jig assembly 1.

Preferably, the replaceable insert 13 is manufactured from a material similar to that of the jig assembly, for example a metal such as Aluminium, thus providing a durable guiding surface.

Alternatively, the replaceable insert 13 can be manufactured from a number of other suitable materials, depending upon the intended use of the jig assembly.

For example, if the jig assembly is being used by a DIY r enthusiast for a small number of cutting tasks, the replaceable insert can be manufactured from a less expensive and/or less hardwearing material, such as medium density fibre board (MDF). If the jig assembly is being used for semi-professional use, the replaceable insert could be manufactured from a material whose properties and/or cost are somewhere between those of a metal and MDF, respectively, for example a laminate or plastic.

The invention has the advantage of enabling a damaged or worn guide slot to be replaced without having to replace the entire jig. It also allows the replaceable insert 13 to be manufactured from a different material to that used in the main jig body 3, thereby permitting a choice of replaceable inserts 13 to be provided for different uses.

As another alternative, the jig body 3 can be manufactured from a material that is less expensive and/or less hard wearing than the replaceable insert.

For example, the jig body could be manufactured from a material such as MDF, while the replaceable insert 13 is manufactured from a metal such as Aluminium. In this manner, the less hardwearing properties of the MDF are suitable for the less important cutting tasks, for example the cutting of the bolt recesses on the underside of the worktop, while the more hardwearing replaceable insert 13 ensures an accurate cut for the more important cutting tasks, for example the postform joint where two surfaces are being joined together.

Although the embodiment of Figures 2 to 4 shows the entire guide slot 5 being formed from a replaceable insert 13, it will be appreciated that the replaceable r: insert 13 could also be provided for just a section of a guide surface in the guide slot.

Figure 5 shows a jig assembly according to another embodiment of the present invention. As with Figure 2, the jig assembly 1 comprises a jig body 3, having one or more guide slots (5, 11) and locating holes 23.

However, according to this embodiment, rather than having the male and female guide surfaces 5a, 5b formed from a single replaceable insert 13, the guide surfaces 5a, 5b of the postform joint slot 5 are instead provided by separate replaceable inserts. For example, the replaceable insert 25a forms the guide surface 5a for the female joint of the postform joint slot 5. The replaceable insert 25a comprises one or more locating holes 26, and sits in a recess 27a provided in the jig body 3. The shape of the recess 27a is preferably matched to the shape of the replaceable insert 25a, thereby permitting accurate placement in relation to the locating holes 23 on the jig body 3.

Figure 6 shows that the underside of the jig body 3 comprises a recess 27b for receiving a separate replaceable insert 25b, providing the guide surface 5b for the male joint of the postform joint.

Since the embodiment described in Figures 5 and 6 has replaceable inserts 25a, 25b corresponding to separate guide surfaces, it has the advantage of allowing just the male or female guide surface to be replaced, depending upon which one has been damaged or worn. It will also be appreciated that the replaceable insert could be sub-divided further, so that the replaceable section is only provided for a part of the guide surface that is likely to be worn or damaged, for example a corner section in the guide slot 5.

Alternatively, a guide surface such as the female guide surface 5a could be formed from a number of separate replaceable inserts along the length of the guide surface 5a. This would be advantageous if one particular section of the guide surface was more likely to be damaged or worn than another section or sections. ; According to another aspect of the invention, the jig assembly shown in Figures 2 to 4 can be adapted to receive a replaceable insert 13 from a set of replaceable inserts. Each replaceable insert 13 in the set has the same outer shape for matching the standard opening 12 in the jig body 3. However, each replaceable insert 13 in the set of replaceable inserts can have a different shaped guide surface or slot, each defining a particular cut.

Figure 7a to 7c show different examples of replaceable inserts 13 in a set of replaceable inserts, for use with the jig body 3 shown in Figure 2. Figure 7a shows a postform joint slot 5 as previously discussed above.

Figure 7b shows a peninsular curve 9, whereas Figure 7c shows a series of cable channel holes and recess bolt slot 11. This arrangement allows one or more similarly shaped guide slots to be combined for use with the same opening 12. This has the advantage of allowing the jig assembly to offer more guide slots than previously possible using the available surface area on the jig body 3, ie by simply changing the replaceable insert depending upon the cutting task being undertaken.

The jig assembly described in the various embodiments above has the advantage of enabling a particular guide slot, or part of a guide slot, to be replaced when it has become damaged or worn through repeated use.

The jig assembly is particularly advantageous for the hire industry, since it enables the hiring company to hire the main jig body 3 with a replaceable insert 13, similar to the manner in which grinding tools are hired with cutting discs. Thus, each new hirer can be provided with a new replaceable insert 13, thereby enabling perfect joints to be created. In addition, by having replaceable inserts 13 manufactured from different materials, the hirer can decide which replaceable insert to purchase depending upon the intended use. For example, a wooden insert can be purchased if a very small number of cuts are being made, or a metal insert if a larger number of cuts are planned.

Although the preferred embodiments have been described in relation to a jig assembly for cutting worktops, it will be appreciated that the invention can also be used for other applications in which a guide surface or slot is used to guide a cutting tool.

In addition, although the replaceable inserts 13 have been described as being manufactured from metal, MDF, laminate or plastic, it will be appreciated that other materials could be used, depending upon the intended application of the jig.

Claims

1. A jig assembly for guiding a cutting tool, the jig assembly comprising a jig body having one or more guide surfaces for guiding the cutting tool, characterized in that at least a section of one guide surface is formed by a replaceable insert, the replaceable insert being detachably connected to the jig body.

2. A jig assembly as claimed in claim 1, wherein the jig body comprises an opening for receiving the replaceable insert, the replaceable insert having an outer shape corresponding to that of the opening in the jig body, the replaceable insert having a second opening and/or protection acting as the guide surface for guiding the cutting tool.

3. A jig assembly as claimed in claim 2, wherein the! opening in the jig body comprises a recess adapted to cooperate with a complementary recess in the outer shape of the replaceable insert.

4. A jig assembly as claimed in claim 2 or 3, wherein the jig assembly comprises a set of replaceable inserts for use with the jig body, each replaceable insert in the set having the same outer shape corresponding to the opening in the jig body, but having a different guide surface for guiding the cutting tool.

5. A jig assembly as claimed in claim 1, wherein the jig body comprises a recess for receiving the replaceable insert, wherein the replaceable insert is shaped to fit the recess in the jig body. l

6. A jig assembly as claimed in any one of the preceding claims, wherein the guide surface forms a guide slot for guiding the cutting tool.

7. A jig assembly as claimed in any one of the - preceding claims, wherein the jig body comprises one or more threaded bores for use in detachably connecting the replaceable insert to the jig body using screw fastenings.

8. A jig assembly as claimed in any one of the preceding claims, wherein the replaceable insert is manufactured from a material which is different from that of the jig body.

9. A jig assembly as claimed in claim 8, wherein the replaceable insert is manufactured from a material which is more hardwearing than that of the jig body.

10. A jig assembly as claimed in claim 8, wherein the replaceable insert is manufactured from a material which is less hardwearing than that of the jig body.

11. A jig assembly as claimed in claim 8, wherein the replaceable insert is manufactured from any one of the materials comprising metal, medium density fibre board (MDF), plastic or laminate.

12. A jig assembly as claimed in any one of the preceding claims, wherein the jig assembly comprises one or more guide surfaces for cutting a worktop.

13. A replaceable insert for use with a jig body, the replaceable insert being detachably connected to the jig body and forming with the jig body a jig assembly used for guiding a cutting tool, the replaceable insert comprising: a first section adapted to cooperate with a receiving section on the jig body; and a-second section which acts as a guide surface for guiding the cutting tool.

14. A replaceable insert as claimed in claim 13, wherein the first section is adapted to be closely received within the receiving section on the jig body.

15. A replaceable insert as claimed in claim 14, wherein the first section is adapted to fit an opening in the jig body, and wherein the second section comprises a guide slot for guiding the cutting tool.

16. A replaceable insert as claimed in claim 14, wherein the first section is adapted to fit a recess in - the jig body, and wherein the second section comprises a guide surface for guiding the cutting tool.

17. A replaceable insert as claimed in any one of claims 13 to 16, wherein the replaceable insert comprises one or more holes for use in detachably connecting the replaceable insert to the jig body.

18. A replaceable insert as claimed in any one of claims 13 to 17, wherein the replaceable insert is manufactured from any one of the materials comprising metal, medium density fibre board (MDF), plastic or laminate.

19. A jig body for use with a replaceable insert, the replaceable insert being detachably connected to the jig body and forming with the jig body a jig assembly used for guiding a cutting tool, wherein the jig body comprises at least one section adapted to receive a replaceable insert having a guide surface.

20. A jig body as claimed in claim 19, wherein said section comprises an opening for receiving a replaceable insert.

21. A jig body as claimed in claim 20, wherein the opening comprises a recess for cooperating with a corresponding recess on the replaceable insert.

22. A jig body as claimed in claim 19, wherein said section comprises a recess for receiving a replaceable insert.

23. A jig body as claimed in any one of claims 19 to 22, wherein the jig body comprises one or more threaded bores for receiving screw fastenings used for detachably connecting the replaceable insert to the jig body.

24. A jig body as claimed in any one of claims 19 to 23, wherein the jig body is manufactured from any one of the materials comprising metal, medium density fibre board (MDF), plastic or laminate.