GB2080728A - Making tongue and groove joints. - Google Patents

Abstract

Two guide members (13 and 14) and a stop member (31) are adjustably secured to the a surface provided with an aperture (19). In use the workpiece (20) is clamped below the plane of the surface (18) and the guide and stop means are adjusted to define boundaries so that by moving a router on the surface with its cutting bit extending through the aperture and its peripheral rim in contact with the guides, its cutting bit traces a cut of desired configuration in the workpiece. A template is provided for making a groove and a corresponding tongue. <IMAGE>

Description

SPECIFICATION Method and means of making tongue and groove joints This invention relates to a method and means of making tongue and groove joints in work pieces.

The employment of tongue and groove joints is well known in the art of carpentry and related fields.

It is of course essential that the tongue and the groove of such joints match perfectly in order to provide a secure joint and many sophisticated, and hence relatively expensive, apparata have been suggested in the past for this purpose.

Apart from the question of costs, many other short-comings are also experienced with the known arrangements and it is an object of this invention to provide a method and means which the applicants believe will have advantages over the known arrangements.

According to the invention apparatus for making a tongue or a groove in a work piece by means of a hand operable cutting tool such as a router or the like includes a surface over which the tool can slide, the surface extending in a plane which is fixed relative to the work piece; an aperture in the surface through which the blade of the tool can engage the work piece; and at least one element which is releasably securable relative to the surface in any one of a plurality of positions, the element being adapted to guide the tool while it slides over the surface.

The path which the tool will hence follow while it is sliding over the surface will be in a predetermined relationship to the work piece. Furthermore, by utilising the element in two parallel spaced apart positions to guide the tool while it is sliding along the surface, two parallel disposed cuts may be made in the work piece which may, for example, define either the two outer walls of a tongue in a work piece or the two inner walls of a groove in the work piece.

Alternatively the element may be utilised in the two different positions to cut one of the inner walls of a groove in one work piece and one of the outer walls of a tongue in another work piece which is located in the same relationship to the surface as what the first work piece was when the said wall of the groove was cut into it.

Further according to the invention the apparatus includes a second element also adapted for guiding the tool while it is sliding over the surface, the two elements being spaced apart and movable relative to each other.

In one form of the invention the second element is not movable relative to the surface.

In another form of the invention both elements are releasably securable relative to the surface.

It will be appreciated that by securing the two elements relative to the surface in spaced relationship to each other, the one element may be utilised for guiding the tool while cutting the one wall of a tongue or groove in a work piece and the other element for cutting the other wall of the tongue or groove.

Furthermore, by utilising the two elements in one set of positions to cut a tongue or a groove in one work piece, and then utilising the elements in a second set of positions which is in a predetermined relationship to the first set of positions, a perfectly matching groove or tongue may be cut into another work piece which is located in the same relationship to the surface as what the first work piece was when the tongue or groove was cut into it.

Preferably at least part of the transverse width of the area defined between the two elements is larger than the width of the tool so that when the tool is operative in this part of the area it can be guided by either of the two elements.

Further according to the invention each element is adapted to extend at an angle relative to the axis of the work piece.

It will be appreciated that by utilising an element which extends at an angle to a work piece to guide the tool while it is sliding along the surface, the cut made by the tool in the work piece will extend at an angle relative to its said axis.

Furthermore, by locating the two elements so that they extend on opposite sides of the longitudinal axis of the work piece in splayed relationship to each other, a work piece may be provided with a tongue or a groove of which the walls of each are in tapered relationship relative to each other. By utilising these elements in two different sets of positions in the manner set out above, a perfectly matching tongue and a groove with tapered walls may be cut into two work pieces.

In one form of the invention the surface is defined by the top face of a platform and the guide elements each comprises an elongated member having a longitudinal edge which the tool can engage slidably in order to be guided by it while the tool slides over the platform, the member being adapted towards each end thereof to be releasably securable to the platform in a plurality of different positions.

Preferably each member includes towards each end thereof a transversely extending groove adapted slidably to receive one end of a threaded spigot of which the other end is secured to the platform.

It will be appreciated that this arrangement allows for the member to slide relative to the platform in the transverse direction into any one of a plurality of different positions and that by screwing a nut onto that end of the spigot projecting on the other side of the member, the member may be releasably secured to the platform in any one of such positions.

Furthermore, by moving the two opposite ends of the member to different extents in the transverse direction, the angle at which the same edge may be made to extend relative to the platform may be varied.

In one form of the invention the platform may be an integral part of a table, work bench, or the like.

Applicants have, for example, found the work surface of a type of work bench available on the market, characterised by the fact that its work surface is defined by two elements which are movable relative to each other to constitute the jaws of a vice, particularly suited as a platform for their apparatus.

One such a work bench is for example made by Black and Decker and sold under the registered trade mark 'Work mate'.

In another form of the invention, again, the platform may be a separate unit which is adapted to be used with a table, work bench or the like.

In this latter form of the invention the platform may for example comprise a substantially rectangular component which includes an aperture through which a tool located on the platform can engage a work piece located beneath the platform and which furthermore includes a transversely extending flange intended to be clamped between the jaws of a vice associated with a work bench or the like.

Applicants have also found that a work bench of the 'Work mate' type referred to above lends itself for use with such a platform.

Further according to the invention the apparatus includes a template having at least two faces which are in the same relationship relative to each other as what will be required of the two guide elements in order to guide a tool to cut a tongue or a groove of particular configuration in a work piece, the template being adapted to be located on the surface in the area between the two guide elements so that the latter can each be made to abut one of its faces.

Preferably the template comprises a substantially triangular element of which the two legs extending from the base of the triangle are of equal length and disposed at the same angle to the base.

By locating such a triangular template in the area between the two guide elements, so that the axis of symmetry of the template coincides with the longitudinal axis of the platform, and moving the guide elements until they each engage one of the operative faces of the template, the guide elements will be symmetrically located relative to the longitudinal axis of the platform.

Furthermore, by sliding the template into different positions along the platform, while maintaining its axis of symmetry on the longitudinal axis of the platform, it can be employed in each of the different positions for locating the two guide elements in corresponding different positions where they will be further or nearer to each other but still in parallel relationship to the positions previously occupied by them. The spacing between the two guide elements may accordingly be varied in a controlled manner.

Preferably also the template includes one or more reference marks by means of which the distance of its movement along the said axis may be regulated.

Preferably the template is of a transparent material and includes a line demarkated along its axis of symmetry, the said reference marks also being demarkated on this line.

It will be appreciated that in order to cut a tongue, on the one hand, and a matching groove, on the other hand, in two work pieces with the apparatus according to the invention in the manner referred to above, the setting of the two guide elements relative to each other has to be changed in each instance in a controlled manner. By employing the template in the aforesaid manner it is possible to ensure that the two settings are so accurately controlled that a perfectly matching tongue and groove can be obtained Further according to the invention the cross.

sectional width of the blade ofthe cutting tool is wider at its outermost edge than ow-er the rest'ofthe blade so that it can cut a groove or tongue with tapered sides.

The apparatus accordingly to the invention may i accordingly be employed for making a dovetail type of loint.

The workpiece may be held in a fixedyp-osition relative to the platform in any suXable manner.

Thus, for example, where the apparatus is emplayed in collaboration with a work bench, the work piece may be clamped in a vice or the like associated with the work bench.

In another form of the inventionthe work piece may be held in a lathe or the like to which the .

platform may be releasably seicured..

The invention-also indudes-wltiiin itsscopea method of making a tongue-ora-groovein a work piece by means of a hand operable cutting tool such -- as a routerorthe like including-thestepsof locating the work piece in a predetermined relationship to a guide element and sliding the tool along the guide lament while its blade is in engagement with the work piece.

One embodiment of the ieventionwill now be described by way of example with reference to the enclosed drawings, wherein: Figure 1 is a diagrammatitc perspective view showing part of three work pieces provided with tongue and groove joints accordInto the invention; Figure 2 is a diagrnmmatic'p'erspective viof one embodiment of apparatus according to the inven- tion; Figure 3 is a diagrammatic side elevation' of a router of conventional conwction; Figure 4 is a diagrammatic plan view of a template according to the invention; Figure 5 illustrates the provision of a groove in a work piece using the method and apparatus according to the invention;; Figure 6 illustrates the provision.of a tongue in a work piece using the method and apparatus according to the invention; Figure 7 is a diagrammatic perspectiye view of a work bench of a particulartype employed in collaboration with apparatus according to the invention; Figure 8 is a view similar to that of Figure 7 of a platform according to the invention; * > Figure 9 is a cross sectional view of the platfornBof Figure 8 employed in collaboratiop-with the work bench of Figure 7; and Figure 10 is a cross sectional view of another embodiment of a platform according to the inven5 tion employed in callaboration svEth.awork bench vice of conventional construction.

In the embodiment shown in figure 2, the appar- atus according to the-invention includes a table 10 which is supported on ground gageable legs 1Kt and which includes a smooth horizontally extending top 12.

A pair of guide elements 1 are are adapted to be releasably secured to table to 12 @@@@@suring means of which only one @@@@@@@@ @@@@@@ means 15 comprises a threaded spigot of which the one end is fast with top 12 while the other end can pass through a groove 16 in the elements so that it can be secured thereto by fastening a complimentary threaded nut over the end of the spigot.

The inwardly facing longitudinally edges 13.1 and 14.1 of elements 13 and 14 each extends at the same angle relative to the longitudinal axis of the relevant element. By securing elements 13 and 14totop 12 in the positions shown in Figure 2, edges 13.1 and 14.1 accordingly extend at the same angle on opposite sides of the longitudinal axis 17 of table top 12 so that an area 18 of tapered configuration is defined between them.

Top 12 includes a rectangular aperture 19 giving access to a work piece 20 which is secured to table 10 by means not shown in a position under top 12 which is in a predetermined relationship to top 12.

A router 21, (Figure 3) with a rotatable blade 22, of which the length V is adjustable, is adapted to slide on its bottom face 23 on top 12 while its blade 22 projects through aperture 19 to engage work piece 20. Router 21 includes a peripheral rim 24which can slidably engage and hence be guided by either of edges 13.1 or 14.1 of elements 13 and 14 while router 21 slides along top 12 of table 10. Blade 22 is of conical configuration so that it can cut a groove of dovetail like configuration in a work piece, the wider part of the groove corresponding to the cross sectional width W of blade 22 at its outermost end.

Movement of router 21 on top 12 is facilitated by hand engageable knobs 25 which are located on opposite sides of router 21.

The template 26 shown in detail in Figure 4, is of triangular configuration with the sides 26.1 and 26.2 being of exactly equal length. Template 26 is of a translucent plastics material and has a reference line 27 demarkated along its axis of symmetry. Two spaced apart reference marks 28 and 29 are demarkated on line 27. As will be appreciated, the angle (say X) between the base of triangle 26 and its sides 26.1 and 26.2 will determine the taper of the tongue or groove to be cut into the work piece. The distance between marks 28 and 29 again (say D) will be determined by the value of X as well as the cross sectional width (W) of blade 22 according to the equation D = tan X x 1/2 W.

In order to make a groove 30 in a work piece 20, the latter is secured beneath table top 12 in such a position that its longitudinal axis registers with axis 17. Template 26 is located in the area 18 on table top 12 and its reference line 27 brought into register with axis 17. Template 26 is moved until its reference mark 29 is located exactly above the outer end of work piece 20 while keeping reference line 27 in register with axis 17 (see Figure 5). Guide elements 13 and 14 are moved along top 12 until their edges 13.1 and 14.1 abut sides 26.1 and 26.2 of template 26 and elements 13 and 14 are secured to top 12 in these positions by means of bolt and nut arrangements 15. An elongated stop member 31 provided with a longitudinal extending slot 32 is releasably securable to top 12 by means of a nut and bolt arrangement (not shown) which engages slot 32.

Stop 31 serves as a guide for router 21 when its blade 22 is at the inner end 30.1 of groove 30. Once elements 13 and 14 have been secured in position, template 26 is removed and the length of blade 22 of router 21 adjusted so that that part of it intended to engage work piece 20 through aperture 19 is exactly equal to the intended depth U of groove 30 see Figure 1).

Router 21 is placed on top 12 in area 18 in a position so that its rim 24 engages one of the edges 13.1 or 14.1 (say 13.1) and its blade 22 is about to engage the outer end of work piece 20. Because of the particular setting of elements 13 and 14 relative to each other blade 22 will hence be located in a position where it can cut into work piece 20 at point 30.2 when router 21 is moved in the direction of arrow 33 while maintaining its rim 24 in engagement with edge 13.1. By continuing with this movement with rim 24 remaining in sliding engagement with edge 13.1, side wall 30.3 of groove 30 will be cut into work piece 20 up to the point where router 21 engages stop member 31. Side wall 30.4 of groove 30 can then be cut in similar fashion by sliding router 21 along edge 14.1 in the direction opposite to arrow 33.By moving router 21 in the transverse direction between edges 13.1 and 14.1 the material of work piece 20 between side walls 30.3 and 30.4 of groove 30 may be cut out.

In order to cut an exactly matching tongue 34 in a work piece 35 (Figure 6), work piece 35 is secured to table 10 in exactly the same position as what the case was with work piece 20. Nut and bolt arrangements 15 on members 13 and 14 are then loosened, the members moved apart, and template 26 placed on top 12 in area 18 and moved to the position where reference mark 28 is located exactly above the outer end of work piece 35 (see Figure 6). Elements 13 and 14 are then moved until their edges 13.1 and 14.1 respectively abut sides 26.1 and 26.2 of template 26.

Elements 13 and 14 are secured in these positions to table top 12 by means of nut and bolt arrangements 15 and template 26 removed. The setting of elements 13 and 14 relative to each other is now such that when router 21 is located on top 12 with its rim 24 engaging edge 13.1 and with its blade 22 flush against the outer end of work piece 35, blade 22 will cut into work piece 35 at point 35.1 when router 21 is moved in the direction of arrow 33. By continuing with this movement while sliding router 21 along edge 13.1 side wall 34.1 of tongue 34 will be cut into work piece 35 up to the point where router 21 engages stop member 31. By continuing in similar fashion down edge 14.1 in the direction opposite to arrow 33, side wall 34.2 of tongue 34 will be cut into work piece 35.

It will be appreciated that when the material of work piece 35 located between side walls 34.1 and 34.2 and the longitudinal edges of the work piece is cut away, a tongue 34 remains which is of exactly complementary matching configuration to groove 30 in work piece 20.

It will further be appreciated that the tapered configuration of tongue 34 and groove 30 allows for a dove-tail type joint to be formed between work pieces 20 and 35 which will be much more secure than a similar conventional type joint in which the tongue and groove are not so tapered.

In the embodiment shown in Figure 7 a work bench 36 is shown which is of the type including a frame 37 carrying atop 38 comprised of two components 38.1 and 38.2 which are movable relative to each other so that a gap 39 can be defined between them in which a work piece or the like may be clamped. Component 38.2 is mounted stationary on frame 37 while component 38.1 can be moved relative to component 38.2 in the directions of arrows 39 by the turning of two handles 40 which operate screw threaded rods 41 on which component 38.1 is carried.

A pair of guide elements 13 and 14, which are of similar construction to those shown in Figure 2, are releasably secured to components 38.1 and 38.2 respectively by securing means 15 which operates in asimilarmannertothoseshown in Figure 2.

In operation a work piece 41 is clamped between components 38.1 and 38.2 and elements 13 and 14 set in the required relationship to each other and work piece 41 through the employment of template 26 shown in Figure 4. When router 21 is then slid along the top faces of components 38.1 and 38.2 in the area defined between elements 13 and 14 while maintaining its rim 24 in sliding engagement with either of the guiding edges of elements 13 and 14, a tongue or a groove may be cut into work piece 41 in the same manner as that described above.

It will be appreciated that when cutting a tongue into work piece 41 while it is clamped between jaws 38.1 and 38.2 of work bench 36, it will not be possible to remove with router 21 all the material between the side walls of the tongue and the side edges of work piece 41 withoutthe risk of damaging the clamping edges of jaws 38.1 and 38.2. The apparatus shown in Figure 8 serves to overcome this problem.

The apparatus shown in Figure 8 comprises a platform 42 which is provided with a substantially centrally located rectangular aperture 43. The cross sectional width of aperture 23 is more than that of the work piece intended to be worked on. Two guide elements 13 and 14 (similar to those employed with the apparatus shown in Figures 2 and 7) are releasably secured to platform 43 by securing means 15 in a manner similar to that disclosed above. A flange 44 extends at right angles from the underside of platform 43 in a manner so that the upper edge 44.1 thereof projects into aperture 43.

In operation (Figure 9) the flange 44 of platform 42 is located in the gap 39 between jaws 38.1 and 38.2 of work bench 36 so that platform 42 rests on the top faces of components 38.1 and 38.2. A work piece 45 is then located in the gap between flange 44 and the clamping edge of jaw 38.1 in such a position that the upper face of the work piece lies flush with the upper face of platform 42. Jaw 38.1 is then moved towards jaw 38.2 by turning handles 40 until flange 44 and work piece 45 are securely clamped between the jaws.

After elements 13 and 14 have been secured in their required positions, work piece 45 may be worked on in the manner set out above. Since a gap is left on both longitudinal sides of work piece 45, the router will be able to cut away all the material between the edges of a tongue cut into work piece 45 and the side edges of the work piece. It will of course be appreciated that, if so preferred, the apparatus may also be utilised in this manner to cut a groove into work piece 45.

Figure 10 shows how the apparatus according to 1 the invention can be utilised in collaboration with conventional type of work bench vice In this arrangement a platform 46, provided with; an aperture 47 and reieasably securable guide elements 13 and 14, similar to those,of the arrangement of Figure 8, is releasably secured to a substantially L-shaped bracket 48 by,r,ngerg (not shown) which operates in a similar manner as securing means 15 of the arrangements shovçn in Figure 8.

Bracket 48, together with a wor-piece- 49 and a spacer block 50, its clamped betreen s 61 and 52 of a work bench 53. Block 50 merely serves to spaced work piece 49 from the edge of aperture 47 while platform 46 is releasably securable to bracket 48 to allow the position of aperture 47 relative to the work piece to be varied.

Atongue ora groove may then be cut-Intowork piece 49 in a similar manner as that described above for the arrangement of Figure 8.

It will be appreciated that the invention provides an apparatus which is relatively inexpensive to make and relatively simple to operate but which allows for the making of a highly sophisticated tongue and groove joint in work pieces.

It will further be appreciated that also intended for inclusion within the scope of this invention is a work piece provided with a tongue andJorgroov.eraswell as a method of making such a tongue or groove, substantially as herein described.

It will still further be appreciated that there are many variations in detail possible with the method and apparatus according to the invention without departing from the scope of the appended claims.

Claims (30)

1. Apparatus for making. a tongue or a groove in a work piece by means of a hand op,erabl cutting tool such as a router or the like including g surface over which the tool can slide, the surface extending in a plane which is fixed relative-to the work piece; an aperture in the surface through which the blade of the tool can engage the work piece; and at least ong element which is releasably securable relative to.

surface in any one of a plurality of positions, the element being adapted to guidethetool while it slides over the surface.

2. The apparatus of claim 1 .including a second element also adapted for guiding the tool while it is sliding over the surface, the two' elements be: spaced apart and movable relative to each other.

3. The apparatus of claim 2Wherninthe second element is not movable relative toAhe surface.

4. The apparatus of claims I or 2 wherein both elements are releasably securable relative to the surface.

5. The apparatus of anyene olelaims 2-4 wherein at least part of the @@@@@@@ width of the area defined between the two @@@@@@@@ @@@@ than the width of the tool so that when the tool is operative in this part ofthe area it can be guided by either of the two elements.

6. The apparatus of any one of claims 2 - 5 wherein each element is adapted to extend at an angle relative to the axis of the work piece.

7. The apparatus of any one of claims 2 - 6 wherein the surface is defined by the top face of a platform and the guide elements each comprises an elongated member having a longitudinal edge which the tool can engage slidably in order to be guided by it while the tool slides over the platform, the member being adapted towards each end thereof to be releasably securable to the platform in a plurality of different positions.

8. The apparatus of claim 7 wherein each member includes towards each end thereof a transversely extending groove adapted slidably to receive one end of a threaded spigot of which the other end is secured to the platform.

9. The apparatus of claims 7 or 8 wherein the platform is an integral part of a table, work bench, or the like.

10. The apparatus of claim 9 wherein the platform is defined by the work surface of a work bench which is defined by two elements which are movable relative to each other to constitute the jaws of a vice.

11. Theapparatusofclaim 10 wherein the work bench is the one made by Black and Decker under the registered trade mark 'Work mate'.

12. The apparatus of claims 7 or 8 wherein the platform is not an integral part of a table, work bench orthe like.

13. The apparatus of claim 12 wherein the platform comprises a substantially rectangular component which includes an aperture through which a tool located on the platform can engage a work piece located beneath the platform and which furthermore includes a transversely extending flange intended to be clamped between the jaws of a vice associated with a work bench or the like.

14. The apparatus of claim 13 wherein the work bench is of the type claimed in claims 10 or 11.

15. The apparatus of any one of claims 2 - 14 including a template having at least two faces which are in the same relationship relative to each other as what will be required of the two guide elements in order to guide a tool to cut a tongue or a groove of particular configuration in a work piece, the template being adapted to be located on the surface in the area between the two guide elements so that the latter can each be made to abut one of its faces.

16. The apparatus of claim 15 wherein the template comprises a substantially triangular element of which the two legs extending from the base of the triangle are of equal length and disposed at the same angle to the base.

17. The apparatus of any one of claims 15 or 16 wherein the template includes one or more spaced apart reference marks by means of which the distance through which the template is moved may be determined.

18. The apparatus of claim 17 wherein the template is of a transparent material and includes a line demarkated along its axis of symmetry on which line the said reference marks are also demarkated.

19. The apparatus of any one of the preceding claims wherein the cross sectional width of the blade of the cutting tool is wider at its outermost edge than over the rest of the blade so that it can cut a groove or tongue with tapered sides.

20. The apparatus of any one of the preceding claims wherein the workpiece is held in a fixed position relative to the platform in any suitable manner.

21. The apparatus of any one of the preceding claims wherein the work piece is clamped in a vice or the like associated with a work bench with which the apparatus is employed.

22. The apparatus of any one of claims 1 - 20 wherein the work piece is held in a lathe or the like with which the apparatus is employed.

23. Apparatus for making a tongue or a groove in a work piece substantially as herein described and as illustrated in any of the drawings.

24. A method of making a tongue or a groove in a work piece by means of a hand operable cutting tool such as a router or the like including the steps of locating the work piece in a predetermined relationship to a surface which extends in a plane fixed relative to the work piece and sliding the tool along the surface along a path which is determined by one or more guide elements associated with the surface while the blade of the tool is engaging the work piece.

25. The method of claim 24 wherein the two elements are secured relative to the surface in spaced apart relationship to each other and the one element is utilised for guiding the tool while cutting the one wall of a tongue or groove in a work piece and the other element for cutting the other wall of the tongue or groove.

26. The method of claim 24 wherein the two elements are utilised in one set of positions to cut a tongue or a groove in one work piece and then utilised in a second set of positions which is in a predetermined relationship to the first set of positions to cut a perfectly matching groove or tongue into another work piece which is located in the same relationship to the surface as what the first work piece was when the tongue or groove was cut into it.

27. The method of claim 26 wherein the two elements are secured on opposite sides of the longitudinal axis of the work piece in splayed relationship to each other in a first set of positions in order to guide the tool to cut a tongue or a groove with tapered sides in one work piece and then secured in a second set of positions in which each element is in parallel relationship to the position which it occupied during the said first position in order to guide the tool to cut a complementary shaped groove or tongue in another work piece.

28. The method of any one of claims 24 - 27 wherein the two guide elements are brought into the required relationship relative to each other by locating a triangular template in the area between the two guide elements so that the axis of symmetry of the template coincides with the longitudinal axis of the work piece, and moving the guide elements into engagement with the operative faces of the tem plate.

29. A method of making a tongue or a groove in a work piece substantially as herein described with reference to the drawings.

30. The product of the apparatus of any one of claims 1 - 23 or of the method of any one of claims 24 -29.