A MACHINE TOOL

Abstract

A machine tool (100) is arranged to deliver at least one of an energy source and a media, through a processing head (300) onto a work-piece for material addition, inspection or data collection, wherein the machine-tool has a clamping mechanism (202) arranged to temporarily receive the processing-head and wherein the machine tool comprises a stop block (390) having a manifold arranged to deliver at least one of the energy and media and wherein the processing head comprises an anti-rotation arm (391) and connector (600) arranged to be connectable to the stop block and wherein the processing head further comprises a manifold arranged to engage with the stop block manifold when the processing head is connected to receive the energy or media. The machine tool may be a multi-axis machine tool and the stop block can be fixed to the machine tool or may be integrated therein.

Claims

1. A machine tool arranged to deliver at least one of an energy source and a media, through a processing head onto a work-piece for material addition, inspection or data collection, wherein the machine-tool has a clamping mechanism arranged to temporarily receive the processing-head and wherein the machine tool comprises a stop block having a manifold arranged to deliver at least one of the energy and media and wherein the processing head comprises an anti-rotation arm and connector arranged to be connectable to the stop block and wherein the processing head further comprises a manifold arranged to engage with the stop block manifold when the processing head is connected to receive the energy or media.

2. A machine tool according to claim 1 wherein the machine tool is a multi-axis machine tool.

3. A machine tool according to claim 1 or claim 2 wherein the media or energy is conducted from the processing head manifold into the processing head.

4. A machine tool in accordance with claims 1 to 3 wherein the stop block is fixed to the machine tool.

5. A machine tool in accordance with claims 1 to 3 wherein the stop block is integrated into the machine tool.

6. A machine tool in accordance with any preceding claim where in the anti-rotation arm further comprises an orientation collar arranged to at least partially encircle the processing head.

7. A machine tool in accordance with claim 6 wherein the orientation collar comprises a cooling mechanism.

8. A machine tool in accordance with claim 7 wherein a cradle is arranged to preheat a processing head.

9. A machine tool in accordance with any preceding claim wherein the processing head comprises a second anti-rotation arm, and the machine tool comprises a second stop block arranged to engage the second anti-rotation arm.

10. A kit comprising a processing head having an anti-rotation arm and a manifold in combination with a stop block having a cooperating docking-manifold wherein the processing-head is arranged, in use, to be connectable to a clamping mechanism of a machine tool, or the like.

11. A method of connecting a processing-head to a machine tool wherein the processing head has an anti-rotation arm and connector and a manifold, the method comprising: a) providing a machine tool with a stop block dock having a supply manifold; b) causing the machine tool to select the processing-head from a storage location and insert the processing-head into a clamping mechanism of the machine-tool; and c) moving the anti-rotation arm and connector to engage with the stop block; d) moving the processing head manifold into connection with the stop block supply docking-manifold; e) wherein connection of the supply stop block docking-manifold and the processing-head docking-manifold provides a supply of one or more media to the processing-head such that, in use, the or each media can be supplied.

12. The method of claim 11, wherein the steps of moving the anti-rotation arm and connector to engage with the stop block and moving the processing head manifold into connection with the stop block supply docking-manifold occur at the same time.

13. A processing head for a machine tool comprising a body portion intermediate a clamping component and an application component, the body portion having an anti-rotation arm connected to the body portion and a docking manifold on the anti-rotation arm, the docking manifold being adapted and arranged in use to connect to a supply manifold on the machine tool and the docking manifold being arranged to supply at least one of an energy supply and/or a media supply from the supply manifold to the processing head before being applied to a work-piece.

14. A processing head in accordance with claim 13 wherein the processing head has a cooled tamping platen which reciprocates or vibrates against material as it is deposited.

15. A processing head in accordance with claim 13 wherein the processing head has a platen for compacting the material which uses a rocking motion.

16. A docking interface between a processing head and a support structure, wherein the docking interface is arranged to deliver at least one of an energy source and a media through the processing head for additive manufacturing or inspection, wherein the support structure includes: a supply manifold arranged to deliver at least one of the energy and media; a clamping mechanism arranged to receive the processing-head; and a first engagement portion; wherein the processing head is received in the clamping mechanism and includes: a processing head manifold arranged to receive at least one of the energy and media from the supply manifold; and a second engagement portion arranged to releasably engaged the first engagement portion, and wherein an initial motion aligns the first engagement portion and the second engagement portion, and an additional motion enables communication between the supply manifold and the processing head manifold.

17. A docking interface in accordance with claim 16 wherein a cover for avoiding contamination of the or each manifold is opened or removed while the manifolds are fully coupled.

18. A docking interface in accordance with claim 16 or claim 17 wherein the support structure is a machine tool or a robot or a combination of the two and the processing head is arranged to carry out at least one of additive manufacturing or Computer Numerically Controlled (CNC) machining or inspection on a work-piece.

19. A docking interface in accordance with one of claims 16 to 18 wherein the fluid communication is through at least one connector.

20. A docking interface in accordance with any one of claims 16 to 19 wherein an additional movement is actuated by an energy supply.

21. A docking interface in accordance with any one of claims 16 to 20 wherein the supply manifold and the processing head manifold are connected in a multistage docking procedure.

22. A docking interface in accordance with any one of claims 16 to 21 wherein the additional movement comprises a fine movement of the processing head manifold relative to the supply head manifold.

23. A docking interface in accordance with any one of claims 16 to 22 wherein the connector comprises an electrical connector, gas connector, or a water connector.

24. A method of connecting a processing head having a processing head manifold to a support structure having a supply manifold, the processing head being arranged to deliver at least one of an energy source and a media through the processing head for additive manufacturing or inspection, wherein the method comprises: a) inserting the processing-head into a clamping mechanism of the support structure; b) engaging an engagement portion of the support structure with a corresponding engagement portion of the processing head in an initial motion; and c) after engaging the engagement portions, moving the processing head manifold into connection with the supply manifold in an additional motion; d) wherein connection of the supply manifold and the processing head manifold provides a supply of one or more media and/or energy to the processing-head such that, in use, the or each media and/or energy can be supplied.

25. A method of connecting a processing head having a processing head manifold to a support structure having a supply manifold in accordance with claim 24 wherein the engagement of the engagement portions provides a mechanical interface.

26. A method in accordance with claim 24 or claim 25 wherein an additional movement is actuated by an energy supply.

27. A method in accordance with any one of claims 24 to 26 wherein the supply manifold and the processing head manifold are connected in a multistage docking procedure.

28. A method in accordance with any one of claims 24 to 27 wherein the additional movement comprises a fine movement of the processing head manifold relative to the supply head manifold.

29. A method in accordance with any one of claims 24 to 28 wherein one of the supply manifold and the processing head manifold comprises a cover for avoiding contamination of the or each manifold and wherein the cover is opened or removed while the manifolds are fully coupled.

30. A method in accordance with any one of claims 24 to 29 wherein the connector comprises an electrical connector, gas connector, or a water connector.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0108] There now follows, by way of example only, a detailed description of an embodiment of the invention of which:

[0109] FIG. 1 is a schematic illustration of a machine tool;

[0110] FIG. 2 schematically shows a section through a prior art machine tool and docking head;

[0111] FIG. 3a is a schematic illustration of a prior art processing head before connection to machine tool;

[0112] FIG. 3b is a schematic illustration of a prior art processing head after connection to machine tool;

[0113] FIG. 4 is a schematic illustration of a prior art stop block and processing head with an anti-rotation arm and plunger; shows further detail of a manifold used in an embodiment of the invention;

[0114] FIG. 5 shows a view of an alternative processing head before connection of the processing head to a machine tool;

[0115] FIG. 6 shows a view of the embodiment of FIG. 7 after connection of the processing head to the machine tool; perspective view of the embodiment of FIG. 5 illustrating media supplies thereof;

[0116] FIG. 7 is a schematic illustration of a processing head having a number of media supplies;

[0117] FIG. 8 is an illustration of an alternative processing head in accordance with another aspect of the invention attached to a machine tool;

[0118] FIG. 9 is an illustration of a further embodiment of a processing head;

[0119] FIG. 10 is an illustration of a further embodiment of a processing head;

[0120] FIG. 11a is a perspective illustration of an embodiment of a processing head incorporating a cover;

[0121] FIG. 11b is a side view of the embodiment of the FIG. 11a;

[0122] FIG. 12 is an illustration of an embodiment in accordance with a further aspect of the invention, and

[0123] FIG. 13 is an illustration of another embodiment is accordance with the further aspect of the invention.

[0124] FIGS. 14a and 14b are an illustration of prior art connections;

[0125] FIGS. 15a to 15d illustrate the connection steps in accordance with another aspect of the invention;

[0126] FIGS. 16a to 16d illustrate the steps of an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0127] FIG. 1 shows, schematically, a machine-tool 100, which typically comprises a machining head 102 held in a clamping mechanism of the machine-tool 100 and arranged to machine a work-piece 104. Further, the machine-tool 100 is usually controlled by a controller 106 which controls the position of the machining-head 102 as it processes the work-piece 104.

[0128] Most machine-tools 100 are arranged such that the machining-head 102 can be interchanged with other machining-heads 102 in order that the correct machining-head 102 is provided for the task at hand. Providing the example of milling machine, then a first machining-head may be provided for coarse material removal, whereas a second machining-head may be provided for fine material removal.

[0129] As such, machine-tools 100 have tool-changers which can, typically under the control of the controller 106, change the machining head 102 being used by the machine-tool 100 to process the work-piece 104.

[0130] FIG. 2 illustrates a prior art processing-head 200 disclosed in the inventors earlier application WO2014/013247 which connects to the machine-tool 100 using the clamping mechanism 202 of the machine-tool 100 and which can be stored in a store of machining-heads and automatically connected to the machine-tool 100 with a tool-changer thereof. Here the tool-changer may provide a storage-location for processing-heads, machining-heads, etc. which are not currently being used by the machine-tool. Discussion herein refers to a clamping-mechanism 202 and it is assumed that a spindle into which the clamping mechanism 202 connects is part of the machine-tool 100.

[0131] In the embodiment described, the processing head 200 is arranged to focus a laser beam 206 onto the work-piece 104. In other embodiments, other energy sources may be utilized instead of the laser.

[0132] In FIG. 2, a section is shown through the processing-head 200 and it can be seen that a reflector, such as a mirror 208, arranged to move an incoming laser beam 210 through ninety degrees to be incident upon a focusing-lens 212 for creation of the focused-laser beam 206. In addition to the laser beam and optical components, the processing-head 200 also contains one or more ducts to deliver a media. For the example, the media may comprise a polymer and/or metallic powder within a transport fluid which is arranged to be melted by the energy source. The processing head is arranged such that media is delivered through the processing-head and is passed into the energy source such that it is molten or at least semi-molten before the media reaches the work-piece 104. As such, the processing-head can be used to deposit material onto the work-piece and provide a deposition system, which may for example be used to repair parts.

[0133] The machine tool (including a spindle) and the clamping-mechanism 202 have a longitudinal axis, represented by the dashed line XX in FIG. 2. Should a machining-head (such as a milling cutter) be present within the clamping-mechanism 202 then it would rotate about the axis XX. Conveniently, the energy source, which in the embodiment being described is the laser-beam 206, is focused onto a point, area, etc. 213 that lies substantially upon the axis XX on the surface of the work-piece 106.

[0134] Adjacent to the processing head 200 and clamping-mechanism 202 there is provided a supply-unit 214 which provides a housing in which various components are housed. The processing-head 200 comprises a processing-head docking-manifold 201 and the supply-unit 214 comprises a supply docking-manifold 300, which are arranged to mate with one another to connect the supply-unit 214 to the processing-head 200 in the condition as shown in FIG. 2.

[0135] On top of the supply-unit 214 there is provided an energy source 216, which in the embodiment being described is a laser. The laser 216 generates a beam which is transmitted into the supply-unit 214 and passes through a beam expander 217 comprising a first and a second lens 218, 220 respectively. The beam expander 217 is utilized to increase the diameter of the laser beam in order to achieve a better final focus onto the work-piece 104 and reduce the thermal load on the optics.

[0136] The supply-unit 214 also comprises a further reflector 222 arranged to reflect the beam of light from the laser through 90 toward the processing head 200 and the reflector 208 therewithin. Each of the lenses 218, 220 and reflector 222 may be thought of as being guiding mechanism provided within the supply-unit 214.

[0137] The supply-unit 214 also comprises a supply of various media 224 which connects through the manifold to the processing-head 200 when the supply-unit 214 is connected thereto.

[0138] The skilled person will appreciate that supply unit 214 comprises a complex component having a high cost and typically being a relatively large and cumbersome component.

[0139] FIG. 3a is a schematic illustration of an alternative prior art processing head and machine tool in which the processing head 300 having a processing component 301 and a clamping component 302 arranged to clamp to a machine tool 100. In FIG. 3a the processing head is not connected to the machine tool.

[0140] FIG. 3b is a schematic illustration of the machine tool and processing head of FIG. 3a once the processing head 300 has been clamped to the machine tool by the clamping component 302. The processing component 301 may then be deployed to operate on a work-piece 104.

[0141] FIG. 4 shows a schematic illustration of a prior art anti-rotation arm and stop block. The processing head 300 has clamping mechanism 302 arranged to clamp onto a spindle of a machine tool. The processing head 300 further has an anti-rotation arm 304 connected to the processing head. The anti-rotation arm 304 has a plunger 306 which is arranged to releasably connect to a stop block 308 which is connected (not shown) to the machine tool. The anti-rotation arm and the stop block are arranged such that the processing head does not rotate with the spindle.

[0142] FIG. 5 is a machine tool 100 in accordance with the invention in an undocked condition and comprises a machine tool body 50 and a processing head 300. The machine tool body 50 has a stop block 390 attached to the body 50. The stop block comprises an aperture 52.

[0143] The processing head 300 comprises a processing component generally indicated at 301 and a clamping component 302. The clamping component is arranged to be releasably clamped by the machine tool as is illustrated in FIG. 6. The processing head further comprises an anti-rotation arm 391 on which a plunger 392 is mounted. The plunger 392 is arranged to be releasably received in the aperture 52 in the stop block on the machine tool body 50.

[0144] The stop block further comprises a supply manifold 490 mounted on a side of the stop block adjacent the plunger. The processing head further comprises a dockable manifold 491 provided on a side of the anti-rotation arm adjacent the plunger and arranged to be able to dock with the supply manifold 490 on the stop block. FIG. 6 illustrates the processing head clamped in position on the machine tool and with the anti-rotation arm and plunger engaged with the stop block and the supply and processing head manifolds docked together.

[0145] It will be appreciated that the skilled person is able to arrange for fluid and media to be supplied to the supply manifold and from the processing head manifold to the processing component of the processing head.

[0146] In operation, the processing head is connected to the machine tool 100 using a tool changer or other mechanism, under control of the controller. The tool changer is controlled to move the clamping component 302 of the processing head into a clamping mechanism in the nose of the spindle.

[0147] In one example embodiment, the movement of the clamping component 302 into engagement with the machine tool 100 also places the plunger 392 into engagement with the aperture 52 in the stop block 390 and the supply manifold 490 of the stop block 390 into communication with the dockable manifold 491 of the processing head.

[0148] In an alternative embodiment, illustrated in FIG. 12, a first docking step connects the clamping components 302 and the machine tool, and establishes an initial coarse fit between the plunger 392 and the aperture as can be seen in FIG. 12b. The manifolds 490, 491 are then brought into fluid communication in a second docking step. The second docking step may be actuated by convenient energy supply including but not limited to pneumatic or electrical actuation. The second docking step is completed in FIG. 12c and the manifolds 490 and 491 are more closely aligned and connected.

[0149] One or both of the docking manifolds 490, 491 may include a cover 510 to protect the manifold against ingress into the manifolds 490, 491 when they are not connected. The cover may comprise a closure 512 moveable in a track 514 to close the opening 516 into the processing head. Alternative means of providing a closure may be readily envisaged by the skilled person. The second docking step may also actuate removal of the covers. Alternative, a further step of removing the covers may be provided. A processing head with a cover is illustrated in FIG. 11.

[0150] The plunger 392 and aperture 52 provide a convenient coarse position means. It will be appreciated that multi-stage docking can be used with any docking manifolds having a coarse positioning means, and is not limited to stop blocks.

[0151] Further it will be appreciated that although in the embodiment described the docking manifold 491 of the processing head moves to engage with the supply manifold 490 after the alignment/engagement of clamping component 302 to clamping mechanism 202 and the plunger 392 to the stop block 390. It will be appreciated that the sequence may be varied as desired. It will further be appreciated that in some embodiments it is convenient to move the supply manifold 490 rather than the processing head manifold 491.

[0152] In another embodiment illustrated in FIG. 13 the first docking step comprises an alignment of the processing head manifold 491 and the supply head manifold 490 which may be by movement of the processing head manifold 491 towards the supply head manifold 490 or vice versa. Once the manifolds are connected an additional docking movement brings the connectors 600, in this case located broadly within the supply manifold into connection with corresponding connector elements in the processing head manifold. The additional docking movement may be effected by pneumatic or electrical control.

[0153] FIG. 14a shows an embodiment of known docking systems wherein a tapered element such as a tapered pin 610 on the supply manifold is utilized in the first clamping movement to align the docking supply and processing head manifolds when it engages into the corresponding aperture 611 on the processing head manifold. In previously known arrangements a convenient length of pin may not exceed a length of the connectors or may not engage with sufficient accuracy of alignment quickly enough to avoid a collision of the connectors 600 into the manifold is shown in FIG. 14a detail.

[0154] In a method in accordance with the invention in which multi-stage docking is utilized and as illustrated in in FIGS. 15a to 15d the connectors 600 are kept retracted within the supply manifold until the tapered pin 610 enters into coarse alignment as is illustrated in FIG. 15c. The supply and processing head manifolds proceeds to a higher precision alignment as the lead in angle of the pins moves into the aperture and as the additional movement is carried out. Full alignment is achieved once the additional movement has been completed and as shown in FIG. 15d. Then the connectors 600 may be fully engaged and in fluid communication with corresponding connectors 601 in the processing head manifold and a final movement and engagement may be carried out to couple the connectors.

[0155] FIG. 14b shows an alternative embodiment where the alignment is achieved using a clamping mechanism lug 620 that engages with a corresponding aperture 621. This allows the clamp to be partially engaged using a coarse alignment as shown in FIG. 14b. It will be appreciated that as illustrated in the detail of FIG. 14b that the connectors may not be fully aligned between the processing head manifold and the supply manifold and that damage may occur under the clamping movement.

[0156] In accordance with the multistage docking process illustrated in FIGS. 16a to 16d the lug 620 is engaged in the aperture 621. Once the initial clamping motion has been actuated and the processing head manifold and supply manifold are coarsely engaged then the additional movement actuated to align the manifolds with higher precision as shown in FIG. 16c. In this embodiment the additional movement is transverse to the initial clamping movement. Once aligned and clamped as shown in FIG. 16d additional engagement of connectors 600 can be carried out without the risk of damage. The multistage docking also allows for the support structure to position the processing head manifold and the supply manifold relative to one another in a coarse way with very little if any force in preparation for engagement of higher force connectors once clamped.

[0157] Use of multistage docking may be particularly desirable in cases where the connectors are more delicate such as electrical or gas connectors or water connectors. It will also be appreciated that the use of multistage docking may be of particular advantage in relation to robotic systems or to light duty CNC machines which may not have the necessary strength and stiffness to be able to achieve docking in a single motion without risking delicate connectors.

[0158] FIG. 7 shows a material processing head arranged to extrude heated polymer with power and media supplied external to the processing head, perhaps through a manifold as described above. In this embodiment the processing head 1150 comprises a clamping mechanism 1152 and a first deposition head 1154 and a second deposition head 1156. The clamping mechanism, which is sometimes referred to as a tool holder, may be an ISO-40 taper or HSK 63a or other suitable tool holder style as is known in the art.

[0159] The processing head is one example representing material extrusion devices as defined by the ASTM F2792 standard. Thus, the deposition heads 1150 is arranged to extrude material to a work-piece. The processing head also comprises a first and a second media supply 1158 and 1160. In this embodiment the media supply comprises a first channel and a second channel 1162 and 1164 each arranged to guide a first and a second filament of polymer forming the media providing the media supplies 1168, 1170. A media is supplied to the first and second channels from a media supply mechanism. The media supply mechanism is arranged to connect to a manifold. A power supply is also provided to the processing head from the manifold, similar mutatis mutandis to the manifold described in earlier figures. A filament feeding mechanism 1166 is located in the processing head and feeds the first and second filament to respective first 1168 and second 1170 heated chambers. The power supply (typically connected via a manifold and the connection is shown here at 1172) supplies energy to first and second heating chambers and within the respective chambers the first and second filaments are heated and a semi liquid media is supplied to the first 1154 and second deposition head 1156.

[0160] It will be appreciated that the tool holder configurations of the machined tool include standard tools and sizes such as ISO40, CAT40, BT40, HSK63A, Capto 6 etc. In addition the configurations and sizes that fall within the scope of the disclosed invention include other sizes and configurations and adapter plates for end effectors of robots.

[0161] Another example of a machine tool in accordance with the invention is illustrated in FIG. 8.

[0162] FIG. 8 is a machine tool 100 in accordance with the invention in a docked condition and comprises a machine tool body 50 and a processing head 300. The machine tool body 50 has a stop block 390 attached to the body 50.

[0163] The processing head 300 comprises a processing component generally indicated at 301 and a clamping component 302. The clamping component is arranged to be releasably clamped by the machine tool. The processing head further comprises an anti-rotation arm 391 on which a plunger is mounted but is not visible in FIG. 8.

[0164] The stop block 390 further comprises a supply manifold 490 mounted on a side of the stop block adjacent the plunger. A media supply 500 is connected to the supply manifold 490. The processing head also comprises a dockable manifold 491 mounted on the anti-rotation arm adjacent the plunger and arranged to be able to dock with the supply manifold 490 on the stop block. FIG. 8 illustrates the processing head clamped in position on the machine tool and with the anti-rotation arm and plunger engaged with the stop block and the supply and processing head manifolds docked together.

[0165] In this embodiment the media supply to the processing head passes through the anti-rotation arm and through ducting 502 into the processing head and thence through the processing head to the processing component.

[0166] It will also be appreciated that the media and/or energy supply may be provided through the docking interface and the anti-rotation arm. Alternatively the docking interface may be through the plunger. Alternatively the energy and media delivery may be arranged through an independent area, preferably adjacent to the stop block and anti-rotation arm. The media supply may in some part pass through ducting provided between the anti-rotation arm and the processing head.

[0167] It will be appreciated that use of the stop block connection to support docking manifolds provides an improved arrangement which is particularly suited for supplying lighter media and less sensitive energy sources to the processing head.

[0168] An example of the use of the machine tool in accordance with the invention is to provide a machine tool arranged to deposit plastics material on a work-piece. The plastics media can be supplied to the processing head in the form of an extruded filament or granules through the docking manifolds as described earlier and then through the ducting 502 into the processing head 300. The plastics material is heated in the processing head and is then deposited through the processing component 301 onto the work-piece 104.

[0169] The arrangement is advantageous in using less complex components and occupying a smaller space around the machine tool so increasing the flexibility.

[0170] A further embodiment of a processing head in accordance with an aspect of the invention is illustrated in FIG. 9. The processing head 300 comprises a body portion 303 intermediate the clamping component 302 and the application component 301. An anti-rotation arm 391 is connected to an upper part of the body portion adjacent the clamping component. A docking manifold 491 is connected to the anti-rotation arm 391. The docking manifold in this embodiment is arranged to dock with and conduct an energy supply and a media supply to the processing head for application of material to a work-piece 104.

[0171] In this example the energy supply is electrical energy and the supply is routed through the manifold and the anti-rotation arm before entering into the processing head. The electrical energy is used to heat the media to be applied to the work-piece. Mechanical motion is also provided by the rotation of the spindle which turns the clamping component 302 which in turn rotates the screw inside the body of the head. Heating zones 406 are provided around the body of the processing head to heat the media.

[0172] Media to be applied to the work-piece is also supplied to the processing head through the manifold. The media may be selected from a range of suitable media. In this case the media comprises plastics pellets 400. From the manifold the plastics pellets 400 are directed through ducting 402 between the manifold and the processing head. The ducting communicates with an internal chamber 403 in the body of the processing head. An Archimedes screw 404 is provided to move the media continuously towards the application component. As the media passes down the body the media is heated by the electrical energy in the heating zones until the plastics pellets are completely melted 408 and ready to be applied to the work-piece by the application component. An additional media in the form of a wire, fiber or filament 410 is supplied to the processing head from the manifold. The wire 410 passes from the manifold to rollers 412 on the application component of the processing head and is applied to the work-piece. As needed it may be convenient to cut the wire, fiber or filament using a blade 413 or other cutting apparatus known in the art to provide discrete lengths during deposition or for finishing purposes. A blade 413 is provided that operates to cut the fiber periodically once it has been extruded. The knife can cut the fiber when it is finished with each continuous feed. In other embodiments the fiber is chopped periodically to produce a chopped fiber reinforcement of the extruded material.

[0173] Furthermore a compacting frame or tamping foot 414 is provided to compact the newly deposited material to achieve smoother and higher density deposition. It is desirable to cool this foot to minimize adhesion of deposited material onto it. The foot may also vibrate or reciprocate against the deposited material.

[0174] Another embodiment of a compacting or tamping feature is shown in FIG. 10 which shows a cross-section through a head with a moveable platen 424. The platen has a first portion extending behind the material being deposited and a second portion, at a non-parallel angle to the first portion, extending ahead of the being deposited. The paten 424 rotates or rocks back and forth to provide compaction to the deposited material as it changes from position a to position b. The axis of rotation 425 may be perpendicular to the feed direction (as illustrated) or may take alternative alignments including random alignments.

[0175] In the examples discussed above, the stop block 390 is attached to the side of the body 50 of the machine tool 50. However, it will be appreciated that this is by way of example only. The stop block 390 may be connected to or integrated in other parts of the machine tool. For example, the stop block 390 may be integrated into the machine's spindle, spindle housing, Z-axis casting or other structure. The stop block 390 should be connected to or integrated with a stationary part of the machine tool, such that when an appropriately arranged anti-rotation arm 391 engages the stop block, to prevent rotation of the processing head.

[0176] In the examples discussed above, the processing head 300 has a single anti-rotation arm 391. However, in an alternative embodiment, the processing head 300 may include two anti-rotation arms 391, spaced by 180 degrees around the processing head 300. Each arm may incorporate a plunger or other connector to engage the stop block 390. The provision of two arms provides for multiple connecters, to improve alignment between the processing head 300 and machine tool. The stop block 390 may extend around the machine tool such that both arms engage the same stop block 390. Alternatively, separate stop blocks 390 may be provided around the machine tool. One or both of the stop blocks 390 and anti-rotation arms 391 may include supply manifolds, and/or may supply energy, as discussed above. The anti-rotation arms 391 may be provided at any spacing around the processing head. Furthermore, any number of anti-rotation arms 391 and stop blocks 390 may be provided.