This invention relates to worktable systems capable of multi-functional use in connection with building work, carpentry and the like.

A wide variety of apparatus is known for use in supporting and/or clamping workpieces which are to be sawn, cut or drilled. However, known apparatus do not satisfactorily meet the range of requirements which apply to many craftsmen and amateur users. In particular, there is no apparatus of this nature which enables the user to deal readily with sheet materials as typically supplied in sheets of about 2400 mm by 1200 mm.

According to the present invention there is provided a worktable system comprising a supporting structure and a carriage mounted on the supporting structure, the carriage being slidable horizontally to enable a workpiece or a tool to be carried along the line of displacement of the carriage, and the carriage being lockable in a selected position to provide an adjustable fixed point for a guide for movement of a workpiece in a direction transverse to said line of

displacement.

Preferably, the carriage is also tiltable in a vertical plane about an axis on the supporting structure with the carriage adjusted to bring any desired point of its slidable movement to said axis.

Another aspect of the present invention provides a worktable system comprising a worktable supporting structure, a worktop secured to said supporting structure, and a plurality of extension pieces releasably securable to said supporting structure to form spaced, relatively narrow extensions of the worktop, the extension pieces each having a length substantially greater than its width and having a proximal end provided with means for securement to the worktable supporting structure and a distal end having a supporting leg.

From another aspect, the invention provides a clamp for use with a worktable, comprising a clamp body, a clamp member mounted on the clamp body for movement away from and towards the clamp body along an axis, manually operable means for applying a force urging the clamp member away from the clamp body along said axis, and means for mounting the clamp body in a desired one of a plurality of positions on a work surface.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a schematic side view illustrating the principles of operation of preferred embodiments of the invention; Fig. 2 is a schematic plan view corresponding to

Fig . 1 ; Fig. 3 is a plan view of a worktable forming a first embodiment of the invention; Fig. 4 is an end view of part of the worktable of Fig. 3, to an enlarged scale; Fig. 5 shows a detail of Fig. 3 to an enlarged scale; Fig. 6 is a side view corresponding to Fig. 4; Fig. 7 is a plan view of a clamp member used in Fig. 6; Fig. 8 is a partial side view of the clamp member; Fig. 9 is a cross-sectional end view of a mechanism used in this embodiment; Fig. 10 is a partial side view of the worktable including the mechanism of Fig. 9; Fig. 11 is a plan view of another worktable forming a second embodiment of the invention; Fig. 12 is a side view corresponding to Fig. 11; Fig. 13 is a plan view of an element used in this embodiment; Fig 14 is a partial cross-section on the line 14-14 of Fig. 11; Fig. 15 is a partial cross-section on the line 15-15 of Fig. 11; Fig. 16 is a cross-sectional plan view corresponding to Fig. 15; Fig. 17 is a side view, partially disassembled, of part of this embodiment; Fig. 18 is a plan view illustrating a fence guide which may be used with the foregoing embodiments; Fig. 19 is a partial cross-section of the arrangement of Fig. 18; Fig. 20 is a plan view showing the use of extension pieces in accordance with an aspect of the present invention; Fig. 21 is a similar view showing the extension

pieces in a different orientation; Fig. 22 is a partial cross-section illustrating the attachment of the extension pieces in the foregoing Figures; Fig. 23 is a plan view of an element of Fig. 22; Fig. 24 is a front view of part of Fig. 22; Fig. 25 is a cross-section illustrating one form of connection of extension pieces; Fig. 25A is a plan view of a modified form of connection; Fig. 26 is a similar view of an alternative form of connection; Fig. 27 is a partial cross-sectional end view illustrating a leg attachment arrangement for an extension piece; Fig. 28 is a side view corresponding to Fig. 27; Fig. 29 is an end view of two extension pieces of the type shown in the preceding Figures in use; Fig. 30 is an end view of a clamp member for use with the worktable of the present invention; Figs. 31 and 32 are cross-sectional side views of the clamp member in closed and open positions; Figs. 33 and 34 are plan views corresponding to Figs. 31 and 32; Fig. 35 is a cross-sectional side view of a modified clamp member; Fig. 36 is a plan view of a further form of clamp; and Fig. 37 is a side view of yet another form of clamp.

Referring to Figs. 1 and 2, a worktable comprises a base structure 1 on which a carriage 2 is mounted for sliding horizontal movement as indicated by arrow A, and also for pivotal movement about a pivot point 3 as indicated by arrow B. In the preferred forms of the invention, the carriage 2 is in the form of a planar

work surface comprising a rectangular, full-width portion 3a and side pieces 3b and 3c. Aligned with the side pieces 3b and 3c are clamp mounts 4a and 4b which are mounted on the base structure 1 and are longitudinally adjustable relative thereto, as indicated by arrow C. A saw plate 5 is mounted on the base structure 1 and is located within the side pieces 3b, 3c and the clamp mounts 4a, 4b. A cross rail 6 may be removably mounted above the carriage 2 in a position which is longitudinally adjustable, as indicated by arrow D.

The carriage 2 and the clamp mounts 4a, 4b are provided with mounting means (not shown in Figs. 1 and 2) which permit clamping and/or supporting members to be located thereon, as will be described.

The horizontal sliding movement of the carriage 2 allows a workpiece to be moved with respect to a tool in a fixed position on the support structure 1. Alternatively, the carriage may be slid to bring a workpiece into a desired position whereafter the workpiece is moved transversely past a tool, for example by sliding movement along the cross rail 6. Additionally, the carriage 2 may be tilted, as indicated in broken lines in Fig. 1, to assist in loading and maneouvering a large or heavy workpiece such as a large sheet or an article of furniture.

Turning now to Figs. 3 to 10, a first detailed embodiment of the invention will now be described.

In this embodiment, the supporting structure includes a pair of parallel bars 16 one on either side of the worktable. The work surface portion 3a is mounted across the bars 16, and the portions 3b and 3c each on

the supporting structure 1 in a position above one of the bars 16. The clamp mounts 4a, 4b are movable along the structure 1 by turning handles 10.

The saw plate 5 is attached at opposite ends by means of a rod 11 at each end, which rod is dog-legged at either end to a pivot point 12 on a frame member 13 of the supporting structure 1. The saw plate 5 is formed by a sheet metal member with a bent-over flap on each side which may be slipped over the rods 11. This allows the saw plate 5 to be attached as shown in Fig. 1 for rip cutting, or turned through 90° for cross cutting. The dog-leg formation of the rods 11 is provided so that the saw plate 5 may be pulled forwardly, upon which the saw plate 5 is lowered below the level of the work top 3.

The work top surfaces 3a,b,c and the clamp mounts 4a,b are provided with a series of aligned holes 13 along either edge of the worktable, which allow various clamping and other elements to be fixed in desired positions. As seen in Figs. 6 and 7, clamp elements 17 which span the width of the work surface are fitted by means of projecting pegs 18, and can be used to clamp a workpiece between them by relative movement of the clamp mounts 4 and/or the work surface 3. The clamp elements 17 may be mounted such that the work is clamped between plain faces 17a. The clamp elements 17 also have faces 17b which can be used as a fence guide for rip cutting, and have a cut-out portion 17c allowing the element to be used as a workpiece support in cross cutting or as a fence guide in routing.

As seen in Fig. 8, the pegs 18 may suitably be rounded off on their outer sides to allow for easy location in the holes 13.

There will now be described, with particular reference to Figs. 9 and 10, the arrangement for providing controlled sliding and tilting movement of the work surface 3.

At either side of the work surface, a cogged wheel 20 engages in a cogged track 21 secured to the underside of the parallel bar 16. The cogged wheels 20 are mounted on an axle tube 22 which surrounds a rod 23 threaded at its ends and secured by nuts 24. The nuts 24 also hold extension pieces 40 against a rotary brake guide 26 which may turn in a spacer 41.

The axle tube 22 turns in ball bearing races 25, each of which is a sliding fit in a cavity of the brake guide 26 and is biased inwardly by a spring 27. A spacer 28 is provided between the ball bearing race 25 and the cogged wheel 20. The rotary brake guide 26 is fitted into a spacer 29 which may be slid into the frame member 13 from the end of the worktable.

The body of the rotary brake guide 26 is cylindrical and its exterior surface is a sliding fit with a brake member 30. A brake lever 31 has a circular section engaged with a hole in the brake member 30, and an eccentric portion screw-threadedly engaged in the brake guide 26, such that turning movement of the brake lever 31 moves the brake member 30 towards and away from the cogged wheel 20.

As best seen in Fig. 10, the spacer 41 is slid into the frame member 13 at the point 32. The extension piece 40 of the rotary brake guide 26 engages on a bottom lip return of the parallel bar 16 and may have a wheel 33 mounted on it to reduce friction. The extension piece 40, which is fixed for rotation with the rotary brake

guide 26, may be locked in a horizontal position by a spring loaded catch 34. Release of the catch 34 by operation of its lever 35 permits the extension piece 41 to rotate about the pivot point defined by the rod 23.

A second embodiment is shown in Figs. 11 - 17.

Referring first to Figs. 11 and 12, the top has a frame consisting of two longitudinal members 100 and two cross members 101 of extruded aluminium, joined at the corners by moulded plastic angle members 103. Parallel bars 104 on either side are shown displaced beyond the end of the table towards the right. The parallel bars 104 are joined by a cross member 114 which slides over the work top. As seen in Fig. 11, the cross member 114 may comprise a flat plate with an upstanding projection.

The work top comprises a saw plate 105 which is attached to the top frame by interlocking comb elements 106. The work top further comprises two sections 107 and 108 attached to the top frame by similar comb elements 109. The saw plate 105 and the sections 107, 108 may be positioned at desired locations along the top frame by engagement of the comb elements 106 and 109. The saw plate, as in the first embodiment, may be oriented in the position shown or at 90° to that position.

Fig. 13 illustrates a suitable comb element, which may be of moulded plastics.

A fence guide 110 is fitted to the parallel bars 104, again by an interlocking comb arrangement 111, which permits it to be secured in a desired position along

the length of the parallel bars 104.

The plastic angle members 103 are used to mount cogged wheels 112, one at each corner of the work surface. As best seen in Fig. 15, at either end of the work surface an axle rod 113 is rotatable in ball bearings 115 secured in the angle members 103. A rotary brake guide 116 comprises a cylindrical projection 117 engaging in a circular channel in the face of the angle member 103. On the outer face of the rotary brake guide 116 are two parallel projections 118 engaging in channels in the inside face of the parallel bar 104, thus holding the bar 104 down onto the cogged wheel 112. A toothed strip 119 on the bar 104 drivingly engages the cogged wheel 112.

A sliding lock 120 is provided which may be engaged with the rotary brake guide 116 to lock it in position. The cogged wheel 112 may be braked by a brake lever 121 which turns a rotary wedge 122 around a cylindrical projection of the rotary brake guide to bring a brake member 123 into and out of engagement with the wheel 112.

Thus, the brake lever 121 may be used to lock the sliding movement of the work surface, while the lock 120 may be used to control rotational movement of the work surface.

This action may be further explained by reference to Fig. 17, in which the parallel bar 104, the cogged wheel 112, and the brake member 123 have been removed. Channels 124 in the cylindrical projection 117 of the rotary brake guide 116 permit the brake member 123 to slide without turning when the brake lever 121 is turned. The lock 120 is shown in the disengaged

condition; sliding it upwardly causes engagement of a tooth on the lock 120 with a notched formation on the exterior of the brake guide 116.

Turning now to Figs. 18 and 19, an extended fence guide 130 is shown being used as a support against which to rest a panel 131 in cross cutting. Attachment points 132 comprise a comb section which may be fitted at any desired point along the table. A central element 133 is slidable along the fence guide 130 and holds the workpiece away from the fence guide, the element 133 having a central recess for receiving the saw blade at the end of cross cutting. Additional elements 134 may be provided for spacing the workpiece away from the fence guide 130. As seen in Fig. 19, the central element 133 may slide in a channel 135 in the fence guide 130, and the additional elements 134 may likewise be slidable in the channel 135. A further channel 136 may be provided on the underside of the fence guide 130 in which plugs such as 137 may be slid to desired positions for engagement with holes in the worktable, or with comb elements 132.

When working with large panels of materials such as plywood and fibreboard, there are problems in handling and supporting the panels. In a preferred feature of the present invention, several forms of which will now be described, this problem is addressed by providing a worktable in accordance with the invention with extension pieces which can be set up to support large workpieces both before and after a cut has been completed.

Fig 20 shows a worktable 140 arranged for rip cutting of a 2400 mm x 1200 mm panel 141. A fence guide 142 (which may be of the form described immediately above)

is attached to the worktable. Extension pieces 143 are attached to the worktable 140 to support the panel 141 as it is cut, and are arranged so that the cut halves remain supported thereafter.

Fig. 21 shows the extension pieces 143 set up for cross cutting of a 2400 mm x 600 mm panel 144.

One means of connecting the extension piece 143 to the worktable is shown in Figs. 22 - 24. In this example, the extension piece 143 is of sheet metal, and is provided with a bent-over tongue 145 which hooks over an attachment bar 146. The attachment bar 146 is itself attached to the worktable 140 by means of brackets 147 which are connected to the worktable frame by means of studs 148 engageable in keyhole slots 149 in a frame member 150 of the worktable. By providing suitable spacing of mountings such as the keyhole slots 149, the attachment bars 146 may be mounted to project from either end of the worktable.

As seen in Fig. 25, the extension pieces 143 may have their longitudinal edges formed with a re-entrant slot 151, which permits two such extension pieces to be connected together side by side by means of clips such as 152. Equally, the tongue 145 at an end of an extension piece 143 may be fitted into the slot 151 in the side of another extension piece 143, to form a T connection.

In a modification shown in Fig. 25A, two extension pieces 143 may be coupled in parallel but spaced relationship by means of a cross member 220 connected at either end with clips 152. The cross member 220 is suitably tubular and is provided with wheel or roller members 221 rotatable on the cross member 220 for ease

of feeding a workpiece across the worktable.

Fig. 26 shows an alternative form of extension piece 143a, fabricated from hollow section extruded aluminium. The longitudinal edges are formed with a concave groove 153. The short edges are closed by a plastic plug 154 having a projecting portion which is a snap fit in the groove 153 to form a T junction as shown, or to fit into an attachment bar on the worktable.

Extension pieces of the nature so far described also require support at the ends remote from the worktable. Figs. 27 - 29 show one example of suitable support. In this example, the extension pieces are sheet metal extension pieces 143 with the longitudinal edges adjacent the distal end formed as flanges 155. Support legs 156 on either side are each apertured to be received on a stud 157 passing through the flange 155. An eccentric lever arrangement 158 may be operated to force a lock member 159 onto the leg 156 to secure it angularly. The support legs on opposed sides of an extension piece 143 may be braced apart by a folding strut 160.

In order that two extension pieces connected side by side may each be supported, the side flanges 155 are preferably provided with pairs of apertures for the studs 157 to provide longitudinally spaced alternative mounting positions for the legs 156 (as shown in full and dotted in Fig. 28) and thus permit pairs of legs to be overlaid as seen in Fig. 29.

Figs. 30 - 35 illustrate a clamp system for use with the worktable of the invention. A clamp member has a body 160 with a cylindrical portion 161 with an angled

end face 163, from which projects a smaller cylindrical portion 162. The cylindrical portions have a central bore 164 of square cross-section. A piston 165 has a central square stud 166 engaging in the bore 164, and a perpendicular annular face 166. A wedge ring 167 engages between the annular face 166 and the angled face 163, and may be turned by a handle 168 to move the piston 165 axially to apply and release force on a workpiece (not shown) .

The body 160 may be provided with a comb section 170 for engagement with a comb-section rail 171, as in Fig. 30, or may be located by a peg 172 in an aperture in a work surface, as in Fig. 35.

The foregoing clamp system when provided with a peg or the like, as in Fig. 35, may be useful independently of the present worktable, particularly with known forms of worktable which are provided with locating holes in their work surfaces, such as the "Workmate" (Trade Mark) products. The same applies to the clamp arrangements which will now be described with reference to Figs. 36 and 37.

Fig. 36 shows a clamp member 200 identical to that of Fig. 35 except that the clamp body 201 is formed with a T slot 202 which is engageable with a T-section projection on the forward face of a clamp positioner 203. The clamp positioner 203 is formed with a longitudinal opening 204 one side of which has a comb formation 205 which can be engaged at a selected longitudinal location with a cooperating formation on the side of a securing member 206. The securing member 206 has a cylindrical projection 207 for insertion in a selected hole in a work surface (not shown).

selected hole in a work surface (not shown) .

Thus the clamp arrangement of Fig. 36 can be engaged with a selected work surface hole, and can be adjusted in length and rotationally as desired before the clamp is operated to secure a workpiece.

In Fig. 37, a vertical bar 210 is mounted in a desired position on a work surface 211 by means of a pair of projecting pegs 212 engaged in holes in the work surface 211. The front face of the bar 210 is formed with a T-section rail 213 along which the clamp member 200 of Fig. 36 may be slid to a desired height.

Modifications may be made to the foregoing embodiments within the scope of the invention as defined in the claims. For example, a unitary carriage/worktop may be used, as for example by affixing tracks to the underside of a solid worktop.