Worktable Clamping Apparatus

The present invention relates to a worktable clamping apparatus for releasably clamping a workpiece between two clamping jaws and particularly, but not exclusively, to a worktable clamping apparatus incorporating a storage means which is retractable beneath a clamping jaw.

Traditional worktables are often provided with a storage channel or trough located centrally below the worktop to accommodate auxiliary items such as tools, rulers, pencils and the like. The position of the storage channel of traditional worktables is chosen such that the auxiliary items are conveniently accessible to the user whilst being sufficiently remote from the worktop surface itself to avoid the risk of obstructing workpieces supported near peripheral regions of the worktop.

Such worktables have been largely superseded by lightweight portable/foldable clamping tables having worktops consisting of two planar convergeable clamping jaws having an overall smaller surface area compared to traditional worktables. There is a risk that auxiliary items stored on or near the worktop of such clamping tables will impede its operation or its folding. Moreover, there is a risk that auxiliary items stored on or near the worktop will be dislodged or swept off by the movement of a workpiece, or through adjustment of the relative positioning of the clamping jaws.

Various means of storing auxiliary items on a portable/foldable clamping table are known. For example, it is known to provide a series of apertures in a lower crossbar of the table's legs to serve as a storage rack for tools.

It is also known to provide a stationary storage tray attached to the substructure of a clamping table. However, neither of these solutions is entirely satisfactory in terms of ergonomics, convenience, ease of use or safety.

According to the present invention, there is provided worktable clamping apparatus for releasably clamping a workpiece, the apparatus comprising two clamping jaws mounted on a supporting substructure, at least one of the clamping jaws being moveable toward and away from the other on an upper frame of the substructure to facilitate the clamping of a workpiece between laterally convergeable clamping edges of the respective clamping jaws; the apparatus further comprising an auxiliary support member connected to the worktable clamping apparatus at a position at or above the upper frame of the substructure and presenting, in use, an upper supporting surface between the respective clamping jaws but below the level of their clamping edges for supporting a workpiece and/or a work- tool; wherein the auxiliary support member is displaceable relative to the respective clamping jaws between a first position in which it is retracted beyond a clamping edge of a clamping jaw such that the surface area of its upper supporting surface is concealed beneath the clamping jaw, and a second position in which the surface area of its upper supporting surface at least partially protrudes beyond the clamping edge of the clamping jaw.

Retraction of the auxiliary support member beyond the clamping edge of the clamping jaw allows unfettered access to the space between the respective clamping jaws when they are mutually spaced.

Preferably, the auxiliary support member provides the dual function of a storage means.

Optionally, the width of the auxiliary support member measured in the clamping direction is greater than the corresponding width of a single clamping jaw.

This arrangement ensures that at least part of the auxiliary support member protrudes from under a clamping jaw when the respective clamping jaws are spaced from each other.

Alternatively, or additionally, the displacement of the auxiliary support member from the second to the first position causes at least part of the auxiliary support member to extend beyond a non-clamping edge of the clamping jaw.

Such movement of the auxiliary support member allows access to be gained to its upper supporting surface irrespective of whether the clamping jaws are spaced, but only when the auxiliary support member at least partially protrudes from beneath the clamping jaw. When movement of the auxiliary support member is restricted to movement over the clamping edge of the clamping jaw, the upper supporting surface facilitates support of a workpiece and/or a work-tool between the respective clamping jaws. However, when movement of the storage means additionally or alternatively involves movement over a non-clamping edge of the clamping jaw, the upper supporting surface facilitates support of a workpiece and/or a work-tool around the other peripheral non-clamping edges of the respective clamping jaws.

Preferably, the auxiliary support member is displaceable in a horizontal plane lying proximate the underside of the respective clamping jaws.

Optionally, the storage means is defined by at least one storage recess formed in the upper supporting surface.

The storage means may take the form of concavities formed in a volume of material having an otherwise planar upper surface. For example, the concavity may be shaped to correspond with the outline and depth of a work-tool to be stored therein.

Optionally, the storage means is a tray and the upper supporting surface is defined by the uppermost surfaces of its upstanding peripheral edges and/or internal partitions.

For example, the tray may be compartmentalised to define storage recesses of varying shapes and depths to suit the items to be stored including, e.g. fixing screws, nails, pencils, rulers etc. The tray may for example be formed from wood, metal or moulded in one piece from a plastics material.

Preferably, locking means are provided to selectively lock the auxiliary support member in a desired position relative to a clamping jaw.

The locking means may, for example, take the form of a supporting bar suspended from a clamping jaw which can be raised or lowered into or out of locking engagement with the underside of the auxiliary support member.

Optionally, at least one supporting leg is provided on the auxiliary support member to provide it with additional support in its first position.

For example, when the auxiliary support member moves over a non- clamping edge of a clamping jaw, the end of the auxiliary support member

remote from the clamping jaw will lack support. By providing one or more supporting legs on the underside of the auxiliary support member, its remote end can be self-supporting against the ground, a table-top or even against the substructure of the apparatus. The supporting legs may be fixed in position or moveable into a supporting position by sliding or pivoting etc.

In a modification of the present invention, a stationary storage means is provided on the worktable clamping apparatus at a position below and between the clamping jaws and lying in a plane below the auxiliary support member.

Preferably, the auxiliary support member is horizontally displaceable over the stationary storage means to form a lid over its contents.

In this way, the auxiliary support member functions as a lid to selectively open and close the stationary storage means.

Preferably, the auxiliary support member is provided with the dual function of a storage means and the two clamping jaws are convergeable over the displaceable storage means to form a lid over its contents.

In this way, the two clamping jaws function together as a lid to selectively open and close the displaceable storage means.

Preferably, the entire substructure is pivotably connected to the stationary storage means to facilitate pivotable displacement of the substructure away from the stationary storage means to provide access thereto.

Accordingly, access to the stationary storage means can be gained in two ways: (i) sliding the auxiliary support member (which may or may not incorporate storage means itself) to expose the underlying stationary storage means; or (ii) pivoting the substructure (inclusive of the auxiliary support member and the clamping jaws) away from stationary storage means.

Optionally, the auxiliary support member is provided with a handle to facilitate carrying of the apparatus.

For example, when the respective clamping jaws are fully converged and the apparatus is fully collapsed, the handle provided on the auxiliary support member (which should be locked in position relative to a clamping jaw) can be used to carry the entire apparatus.

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 plan view of a first embodiment of the worktable clamping apparatus of the present invention having pivotably retractable supports for holding a workpiece between the clamping jaws;

Fig. 2 is a schematic side view of the worktable clamping apparatus of Fig. 1 , the supporting legs of the apparatus having been omitted for clarity;

Fig. 3 is a schematic side view of the worktable clamping apparatus of Figs. 1 and 2 wherein the pivotably retractable supports have been retracted under a clamping jaw to allow the space between the respective jaws to accommodate a workpiece resting on the substructure of the apparatus;

Fig. 4 is a schematic side view of the worktable clamping apparatus of Figs. 1 to 3 wherein the pivotably retractable supports have been retracted under a clamping jaw to allow the space between the respective jaws to accommodate a vertically clamped workpiece accommodated within the footprint of the substructure of the apparatus;

Fig. 5 is a schematic plan view of a second embodiment of the worktable clamping apparatus of the present invention comprising pivotably retractable storage trays for tools and/or auxiliary materials, the storage trays also fulfilling the dual function of providing support to a workpiece positioned between the clamping jaws.

Fig. 6 is a schematic plan view of a modification of the apparatus of Fig. 5 wherein the pivotably retractable storage trays have been replaced by a slidably retractable tray;

Fig.7 is a schematic end view (from the handle end) of the apparatus of Fig. 6 showing the slidably retractable tray coupled to runners attached to an upper frame of the substructure of the apparatus;

Fig. 8 is a schematic plan view of a modification the apparatus of Fig. 6 showing a double width slidably retractable tray half of which is exposed between the clamping jaws to present a supporting surface for a workpiece and/or tools, the other half being concealed beneath a clamping jaw as shown by dashed lines;

Fig. 9 is a schematic plan view of the apparatus of Fig. 8 wherein the slidably retractable tray has been displaced to the right such that the vertical space between the respective clamping jaws is unobstructed;

Fig. 10 is a schematic plan view of the apparatus of Figs. 8 and 9 wherein the respective clamping jaws are fully converged to function as a lid covering the underlying storage trays;

Fig. 11 is a schematic end view (from the handle end) of the apparatus of Figs. 8 to 10 showing the slidably retractable tray resting on an "up-clamp" locking means for locking the tray in position relative to a clamping jaw;

Figs 12 is a is a schematic side view of a modified and reduced-size worktable clamping apparatus comprising both a slidably retractable storage tray and a stationary storage tray;

Fig. 13 is a schematic plan view of the apparatus of Fig. 12 wherein the respective clamping jaws are spaced from each other and the retractable storage tray is moved beyond a non-clamping edge of a clamping jaw;

Fig. 14 is a schematic plan view of the apparatus of Fig. 12; wherein the respective clamping jaws fully converged and the recessed portion of the retractable storage tray is concealed beneath the respective clamping jaws;

Fig. 15 is schematic perspective view of the retractable storage tray of Figs. 12 to 14 wherein its supporting legs and handle can be more clearly viewed;

Fig. 16 is a schematic plan view of a worktable clamping apparatus having a retractable storage tray shown in its open condition with the respective clamping jaws spaced from each and comprising a modified means of attaching the to the upper frame;

Fig. 17 is a schematic plan view of the worktable clamping apparatus of Fig. 16 shown in its closed position with the respective clamping jaws fully converged against each other; and

Fig. 18 is a schematic partial cross sectional view showing the connection between the retractable storage tray and the upper frame.

Figs.1 and 2 show a clamping table of the lightweight portable/foldable type comprising two planar clamping jaws (1 , 2) attached to the upper frame (3) of a substructure by means of jaw mounts (7, 8). The respective clamping jaws (1 , 2) may be converged toward each other and retracted away from each other by means of clamping spindles in the upper frame (3), the spindles being activated by rotation of clamping handles (4) provided at a distal end of the upper frame (3). Two support members (5) are pivotably attached to the underside of jaw (1 ) by means of a bolt (6) and are shown in an open position where they protrude beyond the clamping edge of clamping jaw (1 ) to lie between the respective clamping jaws (1 , 2) where they support a workpiece (W). Such an arrangement may conveniently hold a workpiece in position freeing both of the operator's hands to allow simultaneous rotation of both clamping handles (4). The retracted position of the two support members (5) are indicated by the dashed line (5a).

Figs. 3 and 4 illustrate two situations in which it is necessary to retract the two support members (5) to their retracted position under the clamping jaw (1 ). For example, Fig. 3 shows a workpiece (W) having an increased depth dimension compared to that shown in Fig. 2. For larger workpieces (W) such as this it is often desirable to clamp them at a position spaced from their edges to ensure stability. In order to clamp such a larger

workpiece (W) at a position generally midway between its upper and lower edges, it is supported directly on the upper frame (3) of the substructure of the apparatus in a horizontal orientation. Fig. 4 shows a scenario whereby a workpiece (W) is clamped vertically and extends through the gap in the upper frame (3). This orientation may be particularly suitable for larger panel-type workpieces (W)

Fig. 5 shows a worktable clamping apparatus according to the present invention having two pivotably retractable storage trays (9) taking the form of compartmentalised trays suitable for the storage of auxiliary items such as fixing screws, nails and the like. The trays (9) are shown in their open position where they protrude beyond the clamping edge of clamping jaw (1) into the space between the respective clamping jaws (1 , 2). The retracted (closed) positions of the respective trays under the clamping jaw (1 ) are indicated in dashed lines (9a). The uppermost edges of the upstanding partitioning walls lie in the same plane and provide the dual function of an upper supporting surface for supporting a workpiece (W) and/or work-tools, and for facilitating hands-free clamping of a workpiece. Although the storage trays (9) are each shown to have four equal sized compartments, it will be appreciated that other orientations and sizes and depths are possible dependent upon the nature of the items to be stored. The trays (9) may be formed from a plastics material and may be moulded in one piece, or they may be constructed from wood or metal from one or more parts.

Fig. 6 shows a modification of the worktable clamping apparatus of Fig. 5 whereby the storage tray (10) is slidably retractable instead of pivotably retractable. The retracted (closed) position of the tray under the clamping jaw (1) is indicated in dashed lines (10'). It will be appreciated that this arrangement affords a greater amount of storage space and facilitates

additional support of a workpiece and/or work-tool by virtue of its extended length.

Fig. 7 shows an end view of the worktable clamping apparatus of Fig. 6 and illustrates how the slidably retractable tray (10) is supported by guide rails (10a) attached to opposing inner sides of the upper frame (3) of the substructure.

Fig. 8 show a preferred embodiment of a worktable clamping apparatus according to the present invention wherein the slidably retractable storage tray comprises two conjoined parts (11 , 11 ') to provide a tray having an overall width twice that of the tray (10) of Fig. 6 and approximately equal to the combined width of both clamping jaws (1 , 2). The larger part of the tray (11 ) is shown protruding from beneath the clamping jaw (1 ) beyond its clamping edge such that it lies between the respective clamping jaws (1 , 2). When the larger part (11 ) of the tray is in this position, the smaller part (11 ') is fully concealed beneath the clamping jaw (1 ). The retractable storage tray is slidably mounted on a supporting bar (12) described below with reference to Fig. 11.

Fig. 9 shows the worktable clamping apparatus of Fig. 8 once the larger part (11 ) of the tray has been retracted beneath the clamping jaw (1 ). The retracting movement from left to right as indicated by the arrow causes the smaller part (11 ') of the tray to protrude beyond the opposing non- clamping edge of the clamping jaw (1) to lie between the two clamping handles (4). When the smaller part (11 ') of the tray is in this position, the larger part (11 ) is fully concealed beneath the clamping jaw (1 ). An operator may effect this movement of the tray (11 , 11 ') for one or two reasons: (i) to free the space between the respective clamping jaws (1 ,2) for the sort of clamping operation illustrated in Figs. 3 or 4; or (ii) to gain

access to auxiliary items stored in the smaller part (11 ') of the tray. The smaller part (11 ') of the storage tray is so shaped such that the rotational arc (4a) of the handles (4) are not impeded when the smaller part (11 ') extends beyond the non-clamping edge of the clamping jaw (1).

Fig. 10 illustrates the scenario whereby the moveable clamping jaw (2) has been converged against clamping jaw (1) to effectively form a lid for the larger part (11 ) of the tray whilst its smaller part (11 ') is retracted beneath clamping jaw (1 ). The storage tray (11 , 11 ') is sufficiently close to the underside of the clamping jaws (1 , 2) such that they effectively form a lid thus preventing access to tools or other auxiliary items stored therein, and retaining the tools or other auxiliary items within the storage trays during transportation of the worktable clamping apparatus.

Fig. 11 is an end view of the worktable clamping apparatus of Figs. 8 to 10 and shows a supporting bar (12) provided underneath the storage tray (11 , 11 '). The supporting bar (12) is suspended from the stationary clamping jaw (1 ) by means of bolts (12a) having enlarged heads (12b) which are accommodated in correspondingly shaped recesses in the upper surface of the clamping jaw (1 ). The bolts (12a) may be turned by the operator to raise the supporting bar (12) into locking engagement with the underside of the storage tray (11 , 11 ') such that it is tightly sandwiched between the supporting bar (12) and the underside of the clamping jaw (1 ). The frictional engagement between the storage tray (11 , 11 ') and the surfaces of the supporting bar (12) and the clamping jaw (1 ) are reduced upon lowering of the supporting bar (12) to release the storage tray (11 , 11 ') out of locking engagement. The outline of the supporting bar (12) is also indicated in dashed line in Figs. 8-10.

When the storage tray (11 , 11') is in the position shown in Fig. 10, movement of the supporting bar (12) against the underside of its smaller part (11 ') prevents relative movement of the clamping jaw (1 ) and the storage tray (11 , 11 ') and ensures that the it remains locked beneath the respective clamping jaws (1 , 2) thus facilitating safe folding of the worktable clamping apparatus and its subsequent transportation.

Figs.12 and 13 show a side and plan view respectively of an ultra portable reduced size worktable clamping apparatus having supporting feet (3a) attached to its upper frame (3). The supporting feet (3a) are shown placed on an appropriate surface (16) such as a table top. The apparatus is provided with a slidably retractable storage tray (13) supported by the upper frame (3). The retractable storage tray (13) (shown in isolation in Fig. 15) is provided with a handle (13a) at one distal end; a planar portion (13b) which can be positioned between the respective clamping jaws (1 , 2) to support, for example, a workpiece; a flanged lip (13c) which, in use, abuts against the upper frame (3); and supporting legs (14) at the opposite distal end. In use, the storage tray (13) can be extended from beneath the clamping jaw (2) beyond its non-clamping edge whilst its distal end nearest the handle (13a) is supported from below by the upper frame (3), the opposite distal end being supported on the surface (16) by the legs (14). Accordingly, access to items stored within the tray (13) may be gained from between the respective clamping jaws (1 , 2) or when the tray (13) protrudes beyond the non-clamping edge of the clamping jaw (2).

A second stationary storage container (15) is provided between the respective clamping jaws and between the elongate sections of the upper frame in a plane lying immediately beneath that of the retractable storage tray (13). The retractable storage tray (13) is horizontally displaceable over the stationary storage container (15) such that access to the further

stationary storage container (15) can be obstructed. In this way, the retractable storage tray (13) functions as a lid to selectively open and close the stationary storage container (15). In addition, the respective clamping jaws (1 , 2) are convergeable over the retractable storage tray (13) such that access to the retractable storage tray (13) can be obstructed. In this way, the two clamping jaws function together as a lid to selectively open and close the retractable storage tray (13).

The entire substructure including the clamping jaws (1 , 2), the jaw mounts (7, 8) and the upper frame (3) is pivotably connected to the stationary storage container (15) about a hinge (15a) to facilitate pivotable displacement of the substructure away from the stationary storage container (15) to provide access thereto. Accordingly, access to the stationary storage container (15) can be gained in two ways: (i) by sliding the retractable storage tray (13) to expose the underlying stationary storage container (15); or (ii) by pivoting the substructure and the associated retractable storage tray (13) away from stationary storage container (15) which remains on the surface (16). Appropriate positioning of the hinge means (15a) will allow unimpeded access to the stationary storage container (15) when the substructure is pivoted towards a vertical plane whilst

Fig. 14 is a plan view of the ultra portable reduced size worktable clamping apparatus of Figs. 12 and 13 in a fully closed condition wherein the clamping jaw (1 ) is tightened forward and fully converged against the clamping jaw (2) to form a lid for the contents of the retractable storage tray (13). The stationary storage container (15) may be locked against the retractable storage tray (13) by a locking means (not shown) to prevent movement of the retractable storage tray (13) relative to the stationary

storage container (15) thus allowing the ultra portable reduced size worktable clamping apparatus to be safely carried by its handle (13a).

Figs. 16 and 17 are plan views of a worktable clamping apparatus comprising a retractable storage tray (17). The tray retractable storage tray (17) is slidably mounted on drawer runners (18) shown in more detail in Fig. 18. The retractable storage tray (17) consists of a recessed storage portion and a raised planar portion (17a). The raised planar portion (17a) may be moved to a position whereby it protrudes from beneath the clamping jaw (2) beyond its clamping edge to provide a supporting surface between the respective clamping jaws (1 , 2) to support a workpiece and/or a work-tool.

When the respective clamping jaws (1 , 2) are fully converged against each other as shown in Fig. 17 they provide a lid to prevent access to the contents of the retractable storage tray (17). When in this position, only the raised planar portion (17a) protrudes beyond the non-clamping edge of the stationary clamping jaw (1). Preferably, the area of the recessed storage section is maximised as indicated in Fig. 17 such that it spans the full combined width of the two clamping jaws (1 , 2), and the full length of each clamping jaw (1 , 2) within the footprint of the upper frame (3). A latch arrangement (17c) located on the non-clamping edge of the stationary clamping jaw (1) may be engaged in a slot (17b) provided in the front upstanding wall of the tray's storage portion to prevent movement of the retractable storage tray (17) relative the clamping jaws. Such a latching means facilitates safe folding and/or transportation of the worktable clamping apparatus.

Fig. 18 is a more detailed cross-sectional view showing the structure of the drawer runner (18) and its attachment to the upper frame (3). A wheel

(19) attached to a recessed portion of the retractable storage tray (17) rotates within the drawer runner (18) and an upper lip of the recessed portion engages a larger wheel (20) (shown in dotted line) attached to the upper frame (3). The provision of two wheels (19, 20) in such an arrangement ensures that the retractable storage tray (17) is fully supported at all positions relative to the respective clamping jaws (1 , 2).

Essential to the functioning of the various storage trays (9, 10, 11 , 13, 17) as a means of support for a workpiece (W) and/or work-tools is that the uppermost edges of their upstanding peripheral and partitioning walls each lie in the same general plane. Moreover, the uppermost edges of the upstanding walls must lie sufficiently near the underside of the respective clamping jaws: (i) to optionally facilitate the support of a workpiece (W) and/or a work-tool at an appropriate position proximate the clamping jaws (1 , 2); and (ii) to ensure that items stored in the trays are readily accessible to an operator without undue effort, (i.e. by being positioned near the underside of the clamping jaws such that the operator is not required to stretch or bend down to access them). Accordingly, the storage trays (9, 10, 11 , 13, 17) are coupled to the worktable clamping apparatus at a position at or above the upper frame (3) of the substructure such that the uppermost edges of their upstanding walls lie in a horizontal plane. The horizontal plane is either coplanar with the lowermost surfaces of the respective clamping jaws (1 , 2) whilst still allowing retraction of the storage trays, or is slightly spaced from the lowermost surfaces. The maximum extent of any such spacing is selected to ensure that the types of tools and/or auxiliary items stored within the trays cannot escape when the trays are retracted beneath the clamping jaws (1 , 2) such that the respective jaws (1 , 2) form an effective lid over their contents. The maximum spacing between the uppermost edges of their upstanding walls and the lowermost surfaces of the respective clamping jaws (1 , 2) is

preferably in the range of 0-10 mm, but most preferably in the range 4-6 mm.

This arrangement provides a safer, more ergonomic and more convenient solution to storage needs as compared to existing portable/foldable worktables as well as providing the additional useful function of supporting a workpiece (W) and/or a work-tool at a convenient working height.