The present invention relates to a tooling fixture for and a method of supporting workpieces in a machine operation, in particular in a screen printing operation.

Various tooling fixtures are currently available. One such tooling fixture is disclosed in the applicant's earlier WO-A-2002/089551, which provides for the individual positioning of a plurality of workpieces supported by a workpiece carrier and supports the same when so positioned, for operation by a machine, such as a printing, deposition or placement machine.

The current tooling fixtures are suitable for workpieces which have a planar upper surface, but the present inventors have recognized that problems arise in relation to the use of flexible workpieces, such as thin core and coreless components, which can be warped and present an uneven upper surface. Presenting an uneven upper surface is problematic, in that the upper surface is not in the expected plane for operation by a machine, for example, in not being aligned with a printing screen in a printing operation, which results in poor prints.

It is an aim of the present invention to provide a tooling fixture for and a method of supporting flexible workpieces, including warped workpieces, such as thin core and coreless substrates.

In one aspect the present invention provides a tooling fixture for supporting at least one workpiece in a machine operation, the tooling fixture comprising : at least one support assembly for supporting at least one workpiece in a workpiece-processing position adjacent a machine component; and a workpiece surround which surrounds the at least one workpiece when in the workpiece-processing position and secures the machine component. In one embodiment the at least one support assembly is movable between a lowered, workpiece-receiving position and a raised, workpiece-processing position, in which the at least one workpiece is supported in a workpiece- processing position.

In one embodiment the at least one support assembly is located on a rising table and moved between the workpiece-receiving and workpiece-processing positions by raising and lowering the rising table.

In one embodiment the at least one support assembly comprises a support tower.

In one embodiment the support tower comprises a first body part, a second body part which is movable relative to the first body part and includes a workpiece support platform at an upper surface thereof for supporting a workpiece, and a positioning element, which is operable to move the second body part upwardly relative to the first body part to engage the supported workpiece against a lower surface of the machine component.

In one embodiment the first and second body parts are in sliding relation and define an enclosed cavity in which the biasing element is located.

In one embodiment the workpiece support platform includes a planar upper support surface for supporting a workpiece.

In one embodiment the positioning element comprises a biasing element, which is operable to bias the second body part upwardly relative to the first body part to engage the supported workpiece against a lower surface of the machine component.

In one embodiment the biasing element comprises a resilient element, preferably a spring element, which normally biases the second body part to a raised, extended position, and, on loading, acts to bias a supported workpiece against the machine component.

In another embodiment the biasing element comprises an actuator which is operable to displace the upper body part of the support tower upwardly to bias a supported workpiece against the machine component.

In one embodiment the actuator comprises a piston actuator, preferably a pneumatic actuator.

In one embodiment the actuator comprises a body which includes a piston bore and is coupled to one of the body parts, and a piston ram which is movably disposed in the piston bore and coupled to the other of the body parts, whereby operation of the actuator acts to one of raise or lower the second body part relative to the first body part.

In another embodiment the positioning element comprises a positioner which is operable to displace the upper body part of the support tower upwardly to a predetermined position to position a supported workpiece against the machine component.

In one embodiment the workpiece surround comprises a surround member which includes at least one through aperture which each receive a workpiece when in the workpiece-processing position.

In one embodiment the surround member has a planar upper surface which surrounds the at least one aperture.

In one embodiment the surround member includes a plurality of vacuum apertures at the upper surface thereof which in use is fluidly connected to a negative pressure, preferably a vacuum source, whereby a negative pressure can be developed at the upper surface of the surround member, which acts to secure the machine component thereto. In one embodiment the tooling fixture comprises: a plurality of support assemblies; and wherein the workpiece surround includes a plurality of workpiece-receiving apertures in which respective workpieces are supported by the respective ones of the support assemblies.

In one embodiment the at least one workpiece comprises a flexible workpiece which can have a warped or uneven surface.

In another aspect the present invention provides a processing machine, comprising : a machine component; a transport mechanism for transporting workpieces to the machine component; and the above-described tooling fixture.

In one embodiment the transport mechanism comprises first and second rails along which workpieces are transported to a workpiece-processing zone beneath the machine component and which are movable between a lowered, workpiece-receiving position and a raised, workpiece-processing position, and the surround member is fixed to at least one of the transport rails, such as to be moved therewith.

In one embodiment the at least one workpiece is transported in a workpiece carrier, which includes at least one workpiece support for supporting the at least one workpiece, from which the at least one workpiece is raised by the at least one support assembly.

In one embodiment each workpiece support comprises a through aperture which includes support members at edges thereof for supporting a workpiece.

In one embodiment the machine is a screen printing machine and the machine component comprises a printing screen. In a further aspect the present invention provides a method of supporting at least one workpiece in a machine operation, the method comprising the steps of: providing a machine component; providing at least one support assembly which is operable to position at least one workpiece at a workpiece-processing position against the machine component; providing a workpiece surround which includes at least one workpiece-receiving aperture for surrounding the at least one workpiece when in the workpiece-processing position and securing the machine component; moving the workpiece surround relative to the machine component to a workpiece-processing position adjacent the lower surface of the machine component; securing the workpiece surround to the machine component; and operating the at least one support assembly to position the at least one workpiece in the at least one workpiece-receiving aperture of the workpiece surround and against the machine component.

In one embodiment the step of operating the at least one support assembly comprises the step of: moving the at least one support assembly relative to the machine component to position the at least one workpiece against the machine component.

In one embodiment the at least one support assembly is movable between a lowered, workpiece-receiving position and a raised, workpiece-processing position, in which the at least one workpiece is supported in a workpiece- processing position.

In one embodiment the at least one support assembly is located on a rising table and moved between the workpiece-receiving and workpiece-processing positions by raising and lowering the rising table.

In one embodiment the at least one support assembly comprises a support tower. In one embodiment the support tower comprises a first body part, a second body part which is movable relative to the first body part and includes a workpiece support platform at an upper surface thereof for supporting a workpiece, and a positioning element, which moves the second body part upwardly relative to the first body part and, on loading, positions a supported workpiece against the lower surface of the machine component.

In one embodiment the first and second body parts are in sliding relation and define an enclosed cavity in which the biasing element is located.

In one embodiment the workpiece support platform includes a planar upper support surface for supporting a workpiece.

In one embodiment the positioning element comprises a biasing element, which is operable to bias the second body part upwardly relative to the first body part to engage the supported workpiece against a lower surface of the machine component.

In one embodiment the biasing element comprises a resilient element, preferably a spring element, which normally biases the second body part to a raised, extended position, and, on loading, acts to bias a supported workpiece against the machine component.

In another embodiment the biasing element comprises an actuator which is operative to displace the upper body part of the support tower upwardly to bias a supported workpiece against the machine component, and the step of operating the at least one support assembly further comprises the step of: actuating the actuator to displace the upper body part of the support tower upwardly to bias a supported workpiece against the machine component.

In one embodiment the actuator comprises a piston actuator, preferably a pneumatic actuator. In one embodiment the actuator comprises a body which includes a piston bore and is coupled to one of the body parts, and a piston ram which is movably disposed in the piston bore and coupled to the other of the body parts, whereby operation of the actuator acts to one of raise or lower the second body part relative to the first body part.

In another embodiment the positioning element comprises a positioner which is operable to displace the upper body part of the support tower upwardly to a predetermined position to position a supported workpiece against the machine component.

In one embodiment the workpiece surround comprises a surround member which includes at least one through aperture which each receive a workpiece when in the workpiece-processing position.

In one embodiment the surround member has a planar upper surface which surrounds the at least one aperture.

In one embodiment the surround member includes a plurality of securing apertures at the upper surface thereof, and the step of securing the workpiece surround to the machine component comprises the step of: applying a negative pressure, preferably a vacuum source, to the securing apertures to secure the surround member to the machine component.

In one embodiment the method further comprises the step of: transporting at least one workpiece on a transport mechanism to the machine component.

In one embodiment the transport mechanism comprises first and second rails along which workpieces are transported to a workpiece-processing zone beneath the machine component and which are movable between a lowered, workpiece-receiving position and a raised, workpiece-processing position, and the surround member is fixed to at least one of the transport rails, and, in the step of moving the surround member, the surround member is moved by movement of the at least one transport rail.

In one embodiment the at least one transport rail is moved between the workpiece-receiving and workpiece-processing positions by the rising table.

In one embodiment the at least one workpiece is transported in a workpiece carrier, which includes at least one workpiece support for supporting the at least one workpiece, and, in the step of operating the at least one support assembly, the at least one workpiece is raised from the at least one workpiece support by the at least one support assembly.

In one embodiment each workpiece support comprises a through aperture which includes support members at edges thereof for supporting a workpiece.

In one embodiment the step of providing at least one support assembly comprises the step of: providing a plurality of support assemblies which are operable to bias a plurality of workpieces at a workpiece-processing position against the machine component.

In one embodiment the workpiece surround includes a plurality of workpiece-receiving apertures in which respective workpieces are supported by the respective ones of the support assemblies.

In one embodiment the at least one workpiece comprises a flexible workpiece which can have a warped or uneven surface.

In one embodiment the machine is a screen printing machine and the machine component comprises a printing screen. Preferred embodiments of the present invention will now be described hereinbelow by way of example only with reference to the accompanying drawings, in which:

Figure 1 illustrates an exploded perspective view of a tooling fixture in accordance with a first embodiment of the present invention;

Figure 2 illustrates a vertical sectional view (along section I-I in Figure 1) of the tooling fixture of Figure 1;

Figures 3(a) to (g) illustrate the operation of the tooling fixture of Figure 1;

Figure 4 illustrates a vertical sectional view (along section I-I in Figure 1) of a tooling fixture in accordance with a second embodiment of the present invention;

Figures 5(a) to (g) illustrate the operation of the tooling fixture of Figure 4;

Figure 6 illustrates a vertical sectional view (along section I-I in Figure 1) of a tooling fixture in accordance with a third embodiment of the present invention; and

Figures 7(a) to (g) illustrate the operation of the tooling fixture of Figure 4.

Figures 1 and 2 illustrate a tooling fixture in accordance with a first embodiment of the present invention for supporting at least one workpiece W in a workpiece-processing operation, which in this embodiment is supported by a workpiece carrier 101, typically to enable operation by a machine, in this embodiment a screen printing machine.

For ease of understanding, the present embodiment is described in relation to a tooling fixture for supporting a single workpiece W, but can be extended to support a plurality of workpieces W. In this embodiment the workpiece carrier 101 is transported to a workpiece- processing zone, here at a location beneath a printing screen 102 which includes a pattern of printing apertures 103, along a pair of guide rails 105, 106. In this embodiment one guide rail 105 has a fixed lateral position and the other guide rail 106 is movable laterally, such as to accommodate workpiece carriers 101 of different width.

In this embodiment the workpiece carrier 101 comprises a plate 107 which includes at least one workpiece support 109 for supporting at least one workpiece W, here a single workpiece support 109 for supporting a single workpiece W. As described above, the tooling fixture of the present embodiment can be extended to support a plurality of workpieces W, and in this embodiment, the plate 107 would include a plurality of workpiece supports 109, typically arranged in an array or matrix.

In this embodiment the workpiece support 109 comprises a through aperture 111, here a rectangular aperture, and a plurality of support members 115, which are disposed about the periphery of the aperture 111, here four support members 115 which are located at respective ones of the sides of the aperture 111, for supporting edges of a workpiece W.

In this embodiment the support members 115 are spaced from the upper surface of the plate 107, such as to define a recess for receiving a workpiece W.

The tooling fixture comprises at least one, in this embodiment a single support assembly 125 for supporting at least one workpiece W in a workpiece-processing position, and a workpiece surround 127 which surrounds at least one workpiece W when in the workpiece-processing position and supports a machine component, in this embodiment the printing screen 102. In this embodiment each support assembly 125 comprises a support tower 131, which is movable between a lowered, workpiece-receiving position, as illustrated in Figure 3(a), an intermediate, workpiece-supporting position, as illustrated in Figure 3(b), and a raised, workpiece-processing position, as illustrated in Figures 3(c) and (d), in which a workpiece W is supported in a workpiece-processing position.

In this embodiment the support tower 131 is located on a rising table 133 and moved between the workpiece-receiving, workpiece-supporting and workpiece-processing positions by raising and lowering the rising table 133.

In this embodiment the support tower 131 comprises a first, lower body part 137, here in the form of an upwardly-facing cup, a second, upper body part 139, here in the form of a downwardly-facing cup, which is movable relative to the lower body part 137, and a positioning element 141, here a biasing element, which is located between the lower and upper body parts 137, 139, such as to bias the upper body part 139 upwardly relative to the lower body part 137.

In this embodiment the lower and upper body parts 137, 139 are in sliding relation and define an enclosed cavity 143 in which the biasing element 141 is located.

In this embodiment the upper body part 139 includes a workpiece support platform 145 at the upper surface thereof, which includes a planar upper support surface 147 for supporting a workpiece W.

In this embodiment the workpiece support platform 145 is a sliding fit within the aperture 111 in the workpiece carrier 101, here having the same shape as the aperture 111 in the workpiece carrier 101.

In this embodiment the biasing element 141 comprises a resilient element, here a compression spring, which is sized such as provide a predetermined travel of the upper body part 139 relative to the lower body part 137, here a travel of about 10 mm, when a load is applied thereto.

The workpiece surround 127 comprises a surround member 151, in this embodiment a plate, which includes at least one, in this embodiment a single through aperture 153, here rectangular in shape, which is configured to receive at least one workpiece W when in the workpiece-processing position, and a planar upper surface 155 which surrounds the aperture 153.

The surround member 151 includes a plurality of vacuum apertures 157 at the upper surface thereof and a vacuum port 159 which is fluidly connected to the vacuum apertures 157 and provides for connection to a vacuum source, such that a vacuum can be developed at the upper surface 155 of the surround member 151, which acts to engage a machine component, in this embodiment the printing screen 102, in substantially planar relationship thereto, as illustrated in Figure 3(d). This engagement of the machine component advantageously provides for a more solid reference relative to the surround member 151.

In this embodiment the vacuum apertures 157 are provided by discrete apertures, but could be provided by other structures which have a fluid pathway therethrough, such as a sintered component.

In this embodiment the surround member 151 is fixed to one of the guide rails 105, 106, here the first guide rail 105 which has a fixed lateral position, such as to be movable vertically therewith.

Operation of the above-described tooling fixture will now be described hereinbelow with reference to Figures 3(a) to (g) of the accompanying drawings.

With the transport rails 105, 106 and the rising table 133 in the lowered, workpiece-receiving positions, a workpiece carrier 101 supporting a workpiece W in the workpiece support 109 thereof, is transported along the transport rails 105, 106 to a workpiece-processing zone beneath the machine component, in this embodiment beneath the pattern of print apertures 103 in the printing screen 102, as illustrated in Figure 3(a).

The support assembly 125 is then operated, in this embodiment by raising the rising table 133 to juxtapose the workpiece W with the lower surface of the machine component, in this embodiment the lower surface of the printing screen 102.

The support assembly 125 is raised through an intermediate, workpiece- supporting position, as illustrated in Figure 3(b), in which the rising table 133 engages the transport rails 105, 106 and the workpiece support platform 145 of the support tower 131 is raised through the aperture 111 in the workpiece carrier 101 to lift the workpiece W from the workpiece support 109 thereof, and the upper surface 147 of the workpiece support platform 145 is substantially coplanar with the upper surface 155 of the surround member 151 of the workpiece surround 127.

The support assembly 125 is raised further to a workpiece-processing position, as illustrated in Figure 3(c), in which the upper surface 155 of the surround member 151 is juxtaposed the lower surface of the printing screen 102. In this workpiece-processing position, the support tower 131 and the workpiece W supported thereon have locally raised the printing screen 102, and the workpiece W is at least partially flattened between the upper surface 147 of the workpiece support platform 145 and the lower surface of the printing screen 102.

Next, a vacuum is applied to the vacuum apertures 157 in the upper surface 155 of the surround member 151, which acts to draw the printing screen 102 flat onto the upper surface of the surround member 151, as illustrated in Figure 3(d), which acts to move the upper body part 139 of the support tower 131 downwardly against the bias of the biasing element 141. In this configuration, the workpiece W is in the correct position relative to the printing screen 102, in being rendered flat by the bias of the biasing element 141, which biases the upper surface 147 of the workpiece support platform 145 against the lower surface of the workpiece W, the upper surface of which is biased against the lower surface of the printing screen 102, thereby ensuring a good quality print on the workpiece W, which would not be achieved if the workpiece W was warped or otherwise uneven.

Following operation on the supported workpiece W, in this embodiment a screen printing operation performed by displacing a print head over the printing screen 102, the vacuum is released from the vacuum apertures 157 in the upper surface 155 of the surround member 151, which acts to cause the printing screen 102 to be locally raised at the support tower 131 and the workpiece W supported thereon by the bias of the biasing element 141 acting on the upper body part 139 of the support tower 131, as illustrated in Figure 3(e).

The support assembly 125 is then operated, in this embodiment by lowering the rising table 133 to separate the workpiece W from the machine component, in this embodiment the printing screen 102.

The support assembly 125 is lowered through the intermediate, workpiece- supporting position, as illustrated in Figure 3(f), in which the rising table 133 releases the transport rails 105, 106, with the transport rails 105, 106 adopting the lowered workpiece-receiving position, to the lowered, workpiece-receiving position, as illustrated in Figure 3(g).

In lowering the rising table 133, the workpiece support platform 145 of the support tower 131 is lowered through the aperture 111 in the workpiece carrier 101 to return the workpiece W to the workpiece support 109 thereof. Subsequently, the workpiece carrier 101, which supports the workpiece W in the workpiece support 109 thereof, is transported along the transport rails 105, 106 from workpiece-processing zone beneath the pattern of print apertures 103 in the printing screen 102.

Figure 4 illustrates a tooling fixture in accordance with a second embodiment of the present invention for supporting at least one workpiece W, which in this embodiment is supported by a workpiece carrier 101, typically to enable operation by a machine, in this embodiment a screen printing machine.

Again, for ease of understanding, the tooling fixture of the present embodiment is described in relation to a tooling fixture for supporting a single workpiece W, but can be extended to support a plurality of workpieces W.

This tooling fixture of this embodiment is quite similar to the tooling fixture of the above-described embodiment, and thus, in order to avoid duplication of description, only the differences will be described in detail, with like parts being designated by like reference signs.

The tooling fixture of this embodiment differs from that of the above- described embodiment in the configuration and structure of the support tower 131 of the support assembly 125.

In this embodiment the positioning element 141, here again a biasing element, comprises an actuator 171, here a piston actuator, which is operative to displace the upper body part 139 of the support tower 131 upwardly to bias a supported workpiece W against the lower surface of the printing screen 102.

In this embodiment the actuator 171 comprises a casing 173 which includes a piston bore 175 and is coupled to one of the body parts 137, 139, here the lower body part 137, of the support tower 131, and a piston ram 177 which is movably disposed in the piston bore 175 in the casing 173 and coupled to the other of the body parts 137, 139, here the upper body part 139, of the support tower 131, such that operation of the actuator 171 causes one of the raising or lowering of the upper body part 139 relative to the lower body part 137. In this embodiment the piston ram 177 is extended, such as to raise the upper body part 139, by the application of a positive pressure, here a pneumatic pressure, to the piston bore 175, and retracted, such as to lower the upper body part 139, by the application of a negative pressure, here a vacuum, to the piston bore 175.

Operation of the above-described tooling fixture will now be described hereinbelow with reference to Figures 5(a) to (g) of the accompanying drawings.

With the transport rails 105, 106 and the rising table 133 in the lowered, workpiece-receiving positions and the support tower 131 in the retracted configuration, a workpiece carrier 101 supporting a workpiece W in the workpiece support 109 thereof, is transported along the transport rails 105, 106 to a workpiece-processing zone beneath the machine component, in this embodiment beneath the pattern of print apertures 103 in the printing screen 102, as illustrated in Figure 5(a).

The support assembly 125 is then operated, in this embodiment by raising the rising table 133.

The support assembly 125 is raised through an intermediate, workpiece- supporting position, as illustrated in Figure 5(b), in which the rising table 133 engages the transport rails 105, 106 and the workpiece support platform 145 of the support tower 131 is raised through the aperture 111 in the workpiece carrier 101 to lift the workpiece W from the workpiece support 109 thereof and the supported workpiece W is at a location just below the upper surface 155 of the surround member 151 of the workpiece surround 127. The support assembly 125 is further raised to a workpiece-processing position, as illustrated in Figure 5(c), in which the upper surface 155 of the surround member 151 is juxtaposed the lower surface of the printing screen 102.

Then, a vacuum is applied to the vacuum apertures 157 in the upper surface 155 of the surround member 151, which acts to secure the printing screen 102 on the upper surface of the surround member 151.

Next, the support assembly 125 is operated further, in this embodiment by actuating the actuator 171, here by applying a positive pressure to the piston bore 175, such as to raise the piston ram 177 to raise the upper body part 139 of the support tower 131, which biases the upper surface 147 of the workpiece support platform 145 against the lower surface of the workpiece W, the upper surface of which is biased against the lower surface of the printing screen 102, thereby ensuring a good quality print on the workpiece W, which would not be achieved if the workpiece W was warped or otherwise uneven.

Following operation on the supported workpiece W, in this embodiment a screen printing operation performed by displacing a print head over the printing screen 102, the vacuum is released from the vacuum apertures 157 in the upper surface 155 of the surround member 151, which acts to release the printing screen 102 from engagement with the surround member 151.

The support assembly 125 is then operated, in this embodiment by actuating the actuator 171, here by applying a vacuum to the piston bore 175, such as to lower the piston ram 177 to lower the upper body part 139 of the support tower 131 to a lowered position, in which the workpiece W is separated from the machine component, in this embodiment the printing screen 102, as illustrated in Figure 5(e). The support assembly 125 is then operated further, in this embodiment by lowering the rising table 133.

In lowering the rising table 133, the surround member 151 of the workpiece surround 127 is separated from the lower surface of the machine component, in this embodiment the printing screen 102, and the support assembly 125 is lowered through the intermediate, workpiece-supporting position, as illustrated in Figure 5(f), in which the transport rails 105, 106 are released from the rising table 133 and adopt the lowered workpiece- receiving position.

The rising table 133 is further lowered to the lowered, workpiece-receiving position, as illustrated in Figure 5(g), in which the workpiece support platform 145 of the support tower 131 is lowered through the aperture 111 in the workpiece carrier 101 to return the workpiece W to the workpiece support 109 thereof.

Subsequently, the workpiece carrier 101, which supports the workpiece W in the workpiece support 109 thereof, is transported along the transport rails 105, 106 from workpiece-processing zone beneath the pattern of print apertures 103 in the printing screen 102.

Figure 6 illustrates a tooling fixture in accordance with a third embodiment of the present invention for supporting at least one workpiece W, which in this embodiment is supported by a workpiece carrier 101, typically to enable operation by a machine, in this embodiment a screen printing machine.

Again, for ease of understanding, the tooling fixture of the present embodiment is described in relation to a tooling fixture for supporting a single workpiece W, but can be extended to support a plurality of workpieces W. This tooling fixture of this embodiment is very similar to the tooling fixture of the above-described second embodiment, and thus, in order to avoid duplication of description, only the differences will be described in detail, with like parts being designated by like reference signs.

The tooling fixture of this embodiment differs from that of the above- described embodiment in that the positioning element 141 comprises a positioner in place of a biasing element, and the actuator 171, here a screw actuator, is operative to displace the upper body part 139 of the support tower 131 upwardly to a predetermined position relative to the lower surface of the printing screen 102, thereby, for a workpiece W of known thickness, positioning a supported workpiece W against the lower surface of the printing screen 102.

In this embodiment the actuator 171 comprises a drive mechanism 183, here electrically operated, which includes a threaded coupling 185 and is coupled to one of the body parts 137, 139, here the lower body part 137, of the support tower 131, and a drive member 187 which includes a threaded section 189 which is threadedly coupled to the threaded coupling 185 of the drive mechanism 183 and coupled to the other of the body parts 137, 139, here the upper body part 139, of the support tower 131, such that operation of the actuator 171 causes one of the raising or lowering of the upper body part 139 relative to the lower body part 137. In this embodiment the drive member 187 is extended, such as to raise the upper body part 139, and retracted, such as to lower the upper body part 139, by the operation of the drive mechanism 183 in opposite senses.

Operation is otherwise the same as the tooling fixture of the second- described embodiment and is illustrated in Figures 7(a) to (g) of the accompanying drawings.

Finally, it will be understood that the present invention has been described in its preferred embodiments and can be modified in many different ways without departing from the scope of the invention as defined by the appended claims.