GB2396020A

GB2396020A - Cutting tool guide

Info

Publication number: GB2396020A
Application number: GB0227974A
Authority: GB
Inventors: Clive Stuart Edmundson; Graham Russell
Original assignee: EASI DOES IT Ltd
Current assignee: EASI DOES IT Ltd
Priority date: 2002-11-29
Filing date: 2002-11-29
Publication date: 2004-06-09
Also published as: GB0227974D0

Abstract

A cutting tool guide (10) comprises a guiding member (14) having a planar guiding surface (16) for guiding a cutting tool, and a clamping device (12) for holding the guiding member (14) fixed relative to an article to be cut and to clamp the article to a work surface. The cutting tool guide is also used in a method for cutting an article.

Description

- 1 - CUTTING TOOL GUIDE

The present invention relates to a guide for a cutting tool and in particular, but not exclusively, 5 to a portable mitre guide.

A mitre-bench is a well known tool used in carpentry and related pursuits. Typically, a mitre-

bench comprises a worksurface for supporting a piece of wood or other article to be cut and a clamp for 10 holding the piece of wood stationary relative to the worksurface. A guide for a saw is mounted on the mitrebench and is rotatable relative to the bench so as to cut the piece of wood at a desired angle using a saw or other cutting tool. The rotatable guide ensures 15 an accurate cut.

A mitre-bench is a bulky item which is difficult to transport and typically can only be used when cutting articles within a narrow range of sizes determined by the dimensions of the mitre-bench. Any 20 particular mitre-bench will also typically be adapted for use with only a small selection of cutting tools, or with only a particular saw integral with the mitre-

bench. Accordingly, there is a need for a small, lightweight device which can be used when cutting a 25 piece of wood or other article to ensure that the article is cut at a desired angle. There is also a need for a device which will permit the article to be cut by a wider range of cutting tools.

According to a first aspect of the present 30 invention there is provided a cutting tool guide to assist in accurate cutting of an article comprising: a guiding member having a planar guiding surface for guiding a cutting tool; and clamping means arranged to hold the guiding member fixed relative to the article 35 and to clamp the article to be cut to a separate worksurface. Embodiments of the present invention therefore provide a guide which is compact,

- 2 lightweight and easily transportable since it does not include an integral worksurface. Also, by providing an open or exposed planar guiding surface, or a single guiding surface, embodiments of the present invention 5 may be used with a range of different cutting tools such as hand saws, electric saws, jigsaws and so forth. During cutting, the user need not use their free hand to hold the article if it is already secured in place by the clamping means. The user can therefore 10 keep their hand well away from the cutting blade to minimise the risk that an accident might occur.

Preferably, the clamping means comprises a clamp body and a threaded member rotatable within an aperture of the clamp body to effect clamping.

15 Alternatively, a pincer type clamping means may be used. By utilising simple clamping means the guide is easy to use and the size and weight of the guide are kept to a minimum.

In another preferred embodiment the planar 20 guiding surface comprises a first portion extending in a first direction and a second portion extending in a second direction transverse to the first direction. In this embodiment, the first portion of the guiding surface is positioned above the article and, when the 25 blade of the cutting tool is pressed against the guiding surface it ensures that the cutting tool is at the desired angle. The second portion then presents a guiding surface to the cutting tool as the article is being cut ensuring a straight and accurate cut through 30 the entire thickness of the article. Preferably, the two portions extend in directions perpendicular to one another such that the guiding surface is substantially L-shaped. In a further preferred embodiment, the guiding 35 member provides an internal corner arranged to locate against the article. In an especially preferred embodiment, the internal corner is a right angle so as

3 - to locate against mutually perpendicular faces of the article. Advantageously, the internal corner surface can be positioned to bear upon the article to better secure the article in the clamped position. For 5 example, two adjacent surfaces of an article having a rectangular cross-section may be placed in contact with the internal corner and the pressure from two sides will hold the article firmly in place.

In yet a further preferred embodiment, an angle 10 indicator is provided for indicating an angular orientation of the guiding surface relative to the article. Preferably, the angle indicator comprises an arcuate or substantially semi-circular member having angular values marked thereon. In this embodiment, a 15 user can read off the angular value aligned with a side surface of the article to determine the angle of the guiding surface relative to the article. In an embodiment including both an angle indicator and an internal corner, the internal corner is preferably 20 positioned at the origin of a circular arc on which the angular values are provided such that, when the internal corner surface bears against the article, an accurate reading of the angle between the guiding surface and the side surface of the article may be 25 obtained.

Preferably, the guide further comprises a bearing member having a bearing surface disposed transversely to the guiding surface and arranged to bear upon the article. In this embodiment, when the bearing surface 30 is brought to bear against an upper surface of the article it assists in aligning the guiding surface with the upper surface of the article. More preferably the bearing surface is substantially perpendicular to the guiding surface as this ensures that the article 35 is cut in a direction perpendicular to the upper surface of the article.

According to a second aspect of the present

- 4 invention there is provided a cutting tool guide to assist in accurate cutting of an article comprising a guiding member having a planar guiding surface for guiding a cutting tool, the guiding member being 5 adapted for clamping to said article. Advantageously, a guide embodying this second aspect is attachable and removable from a clamp as desired and a preferred embodiment includes clamping means (such as a G- clamp or C-clamp) for clamping the article to a separate 10 worksurface to which the guiding member can be fixed.

Further advantages and preferred features of this aspect of the present invention will be apparent from the above discussion of the first aspect.

According to a third aspect of the present 15 invention there is provided a method of cutting or mitre cutting an article comprising: providing a cutting tool guide as described above; securing the cutting tool guide relative to the article; and cutting the article with a cutting tool while pressing 20 the cutting tool against the guiding surface to assist in accurate cutting of the article. Carrying out the method steps of this third aspect of the present invention on an article will provide the article with an accurate mitre or bevelled edge.

A preferred embodiment of the present invention will now be described by way of an example and with reference to the accompanying drawings in which: Figure 1 depicts a cutting tool guide embodying 30 the present invention; Figure 2 depicts the guide in use, clamping a piece of wood to a worksurface in preparation for making a mitre cut; and Figure 3 depicts an alternative embodiment of the 35 cutting tool guide.

A guide 10 for a cutting tool such as a saw is shown in Figure 1. The guide 10 comprises a G-clamp

- 5 12, a guiding member 14 having a planar guiding surface 16 for guiding a cutting tool, and an arcuate, roughly semi-circular member 18 having angular values 19 marked thereon for indicating an angle of the 5 guiding surface 16 relative to an article to be cut.

The G-clamp 12 comprises, in known manner, a generally C-shaped clamp body 20 and a threaded bolt 22 movable relative to the clamp body 20 to effect clamping. 10 The guiding member 14 comprises a flat metal plate preferably welded or otherwise fixed to the clamp body 20. The guiding surface 16 is generally L shaped, and has an internal corner surface 24 perpendicular to the guiding surface 16. The internal 15 corner is at the origin of the angular markings 19 on the arcuate member 18.

The arcuate member 18 also comprises a flat metal plate, again preferably welded, or otherwise fixed to the clamp body 20 and fixed to or formed as one piece 20 with the guiding member 14. As shown, the angle between the plate forming the guiding member 14 and the plate forming the arcuate member 18 is preferably about 90 , although other angles could be used to provide a cutting guide to assist in making cuts at 25 angles other than the vertical.

In use, as shown in Figure 2, an article to be cut, for example a piece of wood of rectangular cross-

section 26, is clamped between the guide 10 and a separate worksurface 28. The internal corner surface 30 24 of the guiding member 14 bears upon adjacent upper and side surfaces of the article 26 to ensure that the article 26 is held firmly in place. A lower surface of the arcuate member 18 bears upon the upper surface of the article 26 and is therefore substantially parallel 35 to the upper surface of the article 26. This ensures that the guiding surface 16 is substantially perpendicular to the upper surface of the article 26.

6 - An angle 30 between the guiding surface 16 and the side surface of the article 26 is adjusted as desired by rotating the guide 10. With the internal corner surface 24 bearing against the side surface, 5 the angle 30 can be read from alignment of the side surface with the angular markings 19 on the upper surface of the arcuate member 18. In the arrangement of Figure 2, this angle is approximately 110 .

Alternatively, the guiding surface 16 can simply be 10 aligned with a line drawn at the desired angle on the upper surface of the article 26.

When the guide 10 has been adjusted to the desired position relative to the article 26, the article 26 is secured to the worksurface 28 using the 15 threaded bolt 22 of the G-clamp 12. The user then brings the cutting blade of the cutting tool, such as a saw, into contact with the article 26 and presses the side of the blade against the guiding surface 16.

By applying a slight pressure between the cutting tool 20 and a first portion of the guiding surface 16a before cutting, the article 26 is cut at the desired position and angle. By applying a pressure between the cutting tool and a second portion of the guiding surface 16b during cutting, the user can be confident that he is 25 cutting in a straight line all the way through the article and does not need to periodically check that he is cutting the article as he wishes.

Although a preferred embodiment of the present invention has been described, those skilled in the art 30 will recognise that there are many different variations possible to these preferred features. For example, the guiding member 14 and arcuate member 18 have been generally described above as separate metal plates welded or otherwise fixed together but, in a 35 preferred embodiment these members may be moulded as a single piece in the desired shape before being attached to the clamp body 20. The guiding member 14

- 7 and arcuate member 18 can also be formed as a single flat piece of metal or other suitable material which is then bent to the required shape. This reduces manufacturing costs and is especially preferred since 5 a specially made one-piece guiding member 14,18 can then be fixed to or used with a conventional clamp 12, whether it be a G-clamp or another type of clamp required by the specific circumstances.

Figure 3 depicts an alternative embodiment of the 10 guide 10' in which the guiding member 14 is mounted on a scissor or pincer type clamp 12'. A suitable clamp would be the Quickgrip (RTM) clamp manufactured by American Tool Company, Inc which can be securely locked in a clamping position until a release handle 15 32 is actuated.

In another variant, a one-piece guiding member 14,18 need not be permanently fixed to the clamp 12, but can be attachable and removable as desired whether by hooks, straps, adhesive or some other method. In 20 this way, the number of individual tools contained in a toolbox can be minimised while providing maximum flexibility in their usage.

As noted above, the arcuate member 18 performs two functions: to provide an indication of the angle 25 of the guiding surface 16 relative to a side surface of the article 26 and to provide a planar surface bearing upon the upper surface of the article 26 to ensure alignment of the guide 10 with the upper surface. However, it is not necessary that both of 30 these functions be performed in all embodiments. The arcuate member 18 may provide angular values without providing an alignment function. Similarly, a simple bearing member 18 need not have angular values 19 marked on it and need not be arcuate. In this 35 embodiment, the bearing member 18 may be of any shape provided that there is a surface for bearing upon the article 26 to provide the alignment function. The

- 8 bearing surface will typically be planar but, if the circumstances demand it, for example when the article to be cut is a pipe rather than a block of wood, the bearing surface can be curved. Nevertheless a planar 5 bearing surface is the most flexible in that it will provide an alignment function for the widest range of shapes and sizes of articles.

Claims

- 9 CLAIMS:

1. A cutting tool guide to assist in accurate cutting of an article comprising: 5 a guiding member having a planar guiding surface for guiding a cutting tool; and clamping means arranged to hold the guiding member fixed relative to the article and to clamp the article to be cut to a separate worksurface.

2. A cutting tool guide to assist in accurate cutting of an article comprising a guiding member having a planar guiding surface for guiding a cutting tool, the guiding member being adapted for clamping to 15 said article.

3. A cutting tool guide as claimed in claim 2 further comprising clamping means for clamping the article to a separate worksurface.

4. A cutting tool guide as claimed in claim 1 or claim 3 wherein the clamping means comprises a clamp body and a threaded member rotatable within an aperture of the clamp body to effect clamping.

5. A cutting tool guide as claimed in any of claims 1, 3 or 4 wherein the clamping means comprises a G clamp or C-clamp.

30

6. A cutting tool guide as claimed in any preceding claim wherein the planar guiding surface comprises a first portion extending in a first direction and a second portion extending in a second direction transverse to the first direction.

7. A cutting tool guide as claimed in any preceding claim wherein the planar guiding surface is

- 10 substantially L-shaped

8. A cutting tool guide as claimed in any preceding claim wherein the guiding member provides an internal 5 corner arranged to locate against the article.

9. A cutting tool guide as claimed in claim 8 wherein the internal corner is a right angle so as to locate against mutually perpendicular faces of the 10 article.

10. A cutting tool guide as claimed in any preceding claim further comprising an angle indicator for indicating an angular orientation of the guiding 15 surface relative to the article.

11. A cutting tool guide as claimed in claim 10 wherein the angle indicator comprises an arcuate member having angular values marked thereon.

12. A cutting tool guide as claimed in claim 11 wherein the arcuate member is substantially semi circular. 25

13. A cutting tool guide as claimed in claim 11 or claim 12 wherein the arcuate member and the guide member are formed as a single piece.

14. A guide as claimed in any preceding claim further 30 comprising a bearing member having a bearing surface disposed transversely to the guiding surface and arranged to bear upon the article.

15. A guide as claimed in claim 14 wherein the 35 bearing surface is substantially perpendicular to the guiding surface.

- 11

16. A guide as claimed in either of claim 14 or claim 15 wherein the bearing member and the guiding member are formed as a single piece.

5

17. A method of cutting an article comprising: providing a cutting tool guide as claimed in any preceding claim) securing the cutting tool guide relative to the article; and 10 cutting the article with a cutting tool while ensuring the cutting tool is aligned closely with the guiding surface to assist in accurate cutting of the article. 15

18. A method as claimed in claim 17 further comprising the step of securing the article to a worksurface separate from the guide.

19. A guide for a cutting tool substantially as 20 hereinbefore described with reference to the accompanying drawings.

20. A method of cutting an article substantially as hereinbefore described with reference to the 25 accompanying drawings.