WO2014169338A1

WO2014169338A1 - Automated machine for stacking magnetic core laminations and a method therfor

Info

Publication number: WO2014169338A1
Application number: PCT/AU2014/000437
Authority: WO
Inventors: Peter TEDORE; Michael MATARAZZO; Charles Walker
Original assignee: Aem Cores Pty Ltd
Priority date: 2013-04-19
Filing date: 2014-04-16
Publication date: 2014-10-23

Abstract

An automated machine for stacking magnetic core laminations (10a) that are formed having a web section (16a) and unsupported flanges (12a, 14a) extending from, outer edges of the web section is disclosed. The automated machine includes: a frame (110); a pivotable arm (120) mounted to the frame (110); and a lamination gripping assembly (200) slidably movable along the arm (120), the gripping assembly (200) having at least one gripping element in the form of a suction cup (220) for releasably gripping the web section (16a) of an individual lamination (11a). The arm and gripping assembly are operably movable between a gripping orientation and a stacking orientation. A method of stacking magnetic core laminations is also disclosed.

Description

AUTOMATED MACHINE^' FOR STACKING MAGNETIC CORE LAMINATIONS AND A

METHOD THERFOR

TECHNICAL FIELD

{0001} The present invention relates to the manufacture of magnetic cores of the type formed from multiple stacked ox nested laminations of magnetic strip material .

BACKGROUND

100021 A magnetic core, such as a transformer core, may be formed from multiple stacked or nested laminations of magnetic, strip material. The laminations are formed by a programmable machine that performs^' folding and cutting operations so that each lamination is produced to a predetermined .size and shape. As each lamination is produced by the machine, an operator manually grabs each lamination and stacks or nests them together to build up the magnetic core. Typically, the laminations are stacked together to form mating halves which are later assembled together to form a complete core.

[0003] The process of manually stacking together the laminations of a magnetic core is time consuming, cosily and prone to human error.

[Θ004] There is thus a need to automate this process in order to reduce costs, increase efficiency and repeatability.

[0005] It is against this background and the problems and difficulties associated therewith that the present invention has been developed.

SUMMARY

{0006] According 'to a first aspect of the in vention, there is provided an automated machine for stacking magnetic core laminations that are formed having a web section and unsupported flanges extending from outer edges of the web section, the automa ted machine ineludmg;

a frame;

a pivotable arm mounted to the frame; and

a lamination gripping assembly s!idably movable along the arm, the gripping assembly having at least one grippin element for rdeasabiy gripping the web section of an individual lamination, wherein, the arm arid gripping assembly are operabiy movable between a gripping orientation and a stacking orientation. 7

[^'ΘΟίΠ] In one form the gripping assembly includes a deflecting assembly, the deflecting assembly including a deflector positioned between a pair of spaced-apart gripping elements,

wherein the gripping elements pull the web section, against a reaetiosi force provided by the deflector.

[0008] In one form the deflector assembly includes a bod defining an aperture.

[0009] In one form the automated machine includes a sensor assembly, the sensor assembly for sensing a distance between the web section and a portion of the sensor assembly.

{0010] In one form the sensor assembly produces a laser beam, in use the beam passing through the aperture in the body of the^' deflector.

[Oil 1 j hi one form the gripping assembly includes at least two suction cups,

[00121 1^J1 form the gripping assembly includes two rows of suction cups,

{0013] In one form, the automated machine includes:

a linear drive assembly for sliding the gripping assembly along the arm; and

a rotational drive assembly for rotating the gripping assembly with respect to the arm.

[0014 i one form the linear drive assembly includes a first servomotor.

[0015] la one form the rotational drive assembly includes a second servomotor.

[0016] In one form the gripping assembly includes two adjacent gripping sub-assemblies.

[00171 According to a second aspect of the invention, there is provided a method of stacking magnetic core laminations that are fonned by lamination forming machine, the laminations having a web section, and unsupported flanges extending from outer edges of the web section, the method including the steps of:

(1) presenting a folded lamination such that a web section lies a substantially vertical plane;

(2) positioning a gripping assembly in a gripping orientation adjacent to the web section of the presented folded lamination;

(3) gripping the lamination with the gripping assembly:

(4) transporting the lamination away from the lamination forming machine;

(5) rotating the lamination such. that, the web section lies in a substantially horizontal plane above a stacking station; and

(6) ^' releasing the lamination onto the stacking station, {00183 In one form the method further includes the step of splaying the flanges outwardly, wherein the splaying step occurs prior to the releasing step.

[0019] In one form the step of splaying occurs during the step of gripping.

{0020] one form the step of gripping the lamination takes place while the lamination is held in a folding and cutting machine and prior to a final cut operation.

{0021] In one form the step of gripping the lamination includes:

creatin a lo pressure zone between the web section of the lamination and the grippin assembly by means of suction.

[0022] According to a third aspect of the invention, there is provided a method of stacking laminations having a web section and unsupported flanges extending from outer edges of the web section, the method including the steps of:

positioning a first lamination such that its web lies substantially horizontal with its flanges lying substantially vertical;

gripping the web section of a subsequent lamination;

splaying the flanges of the subsequent lamination outwards and away from each using a deflector positioned between a pair of spaced-apart grippers; and

releasing the subsequent lamination onto the first lamination.

[0023] According t a fourth aspect of the invention, there is provided a metliod of stacking laminations having a web section and unsupported flanges extending from outer edges of the web section, the method including the steps of:

positioning a first lamination such thai its web lies substantially horizontal with its flanges lying substantial ly vertical;

gripping the web section of a subsequent lamination;

splaying the flanges of the subsequent lamination outwards and away from each other using an air stream.; and

releasing the subsequent lamination onto the first lamination,

(0024) In one form, the air stream is induced by compressed air flowing out of a set of nozzles.

[0025] hi one form the set of nozzles include at least a first and a second nozzle, the first nozzle directing air in a first direction and the second nozzle directing air m a second direction, the first and second directions separated by at least 45 degrees.

[0026] In one form the first and second directions are separated by about 90 degrees. BRIEF DESCRIPTION OF DRAWINGS

[0027} Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein:

{0028] Figure 1 is a general arrangement drawing of an embodiment of the invention.

[0029] Figures 2A to 2D are close up views of an automated machine according to the invention showing movement of a lamination horizontally.

[0030] Figures 3 A to 3E are clos up views of an automated machine according to the invention showing transfer of laminations onto a stacking station.

[0031] Figures 4A to 4E are drawings showing transfer of lamination stacks from a stacking station to conveyors.

[0032] Figures 5 and 6 ^' are close up views of air nozzle assemblies.

[0033] Figure 7 is a close up view of an automated machine according to the invention showing the air nozzles within the lamination forming machine,

[0034] Figures 8A to SC are close up views of the gripping assembly.

[0035] Figures 9 A, 9B and 9C are close up view of the suction cup and check valve assembly.

[0036] Figure 10 is a similar view to thai of Figure 3A, but is a close up view to better show an air nozzle location.

DESCRIPTION OF EMBODIMENTS f 037] Referring to Figure 1 , there is shown an automated machine 100 for stacking magnetic core laminations. A magnetic core lamination 10a is shown in Figure 3 A. The lamination 10a has a web section 16a and a pair of unsupported flanges 12a and 14a extending from the outer edges of the web section 16a. Similarly, as adjacent core lamination 10b has a web section 16b and a pair of unsupported flanges 12a and 14b extending from the outer edges of the web section 16b.

[0038] Again referring to Figure 1 , the automated machine 100 sits adjacent a lamination forming machine 20 which is fed sheet steel frora coil machine 5. [0039] It can be seen front Figure- 1 that the stacking station 300 is mounted for sliding movement along rails 510 and 520 with respect to a base 500. This enables the transfer of completed lamination stacks from the position shown in Fig re 1 to a transfer position as shown in Figure 4A,

[0040] The automated machine 100 includes a frame 1 10, which is more clearly shown in Figure 2 A. Referring to Figure 2 A, it can be seen that a pivotal arm 1.20 is mounted to the frame 110 for rotation about an axis 141 in the direction indicated by arrow 142.

[0041] A lamination gripping assembly 200 is shdably moveable along the ami 320. This slidable movement can be see progressively in Figures 2A, 2B, 2C and 2D. More specifically, Figure 2A shows the gripping assembly 200 at a first end 121 of the pivotal arm 120 and Figure 2B shows the gripping assembly 200 at a second end 129 of the pivotal arm 120. Figure 2C shows the gripping assembly 200 at an intermediate position along the pivotal arm 120.

10042) .Referring agai to Figure 2A, it can be seen that the gripping assembly 200 includes two adjacent gripping sub-assemblies 10 for releasably gripping the web section 16a of an indi vidual lamination 19a and the web section 16b of an individual lamination 10b, the individual laminations 10a and .1 Ob being adjacent to each other.

|0043] Figures 2 to 2D show the arm 120 and the gripping assembly 200 in a receiving orientation.

[0044] Now turning to Figures 3 A to 3E, the arm 120 and gripping assembly 200 are shown in a stacking orientation. Movement between the receiving orientation and the stacking orientation is achieved by rotation about the axis 141 in the direction of the arrow 142, This rotation is driven by a rotational drive assembly 140 in the form of a servo motor and low-back lash gear box. In other embodiments of the invention, alternative rotation drive assemblies may be used. For instance, a rotational drive assembly including a toothed belt drive may be used. f0045] A linear drive assembl 130 is provided to slide the gripping assembly 200 along the arm 120. Again, the linear drive assembly 130 is a servo motor in this embodiment of the invention. In Other embodiments of the invention, alternative linear drive assemblies may be used. For instance, a linear drive assembly including a toothed belt drive may be used,

[0046] The grippin sub-assemblies 210 comprise gripping elements in the form of suction cups 220, as is shown in Figures 8 and 9 A to 9C. These suction cups 220 are connected by tubing (omitted for clarity) to a vacuum generator or low pressure source that is fed compressed air from, a recei ver or a reservoir 190, as shown in Figure 3 A. In other embodiments of the invention, alternative gripping elements may be used. (0§47| The gripping assembly 200 also includes a deflecting assembly. The. deflecting assembly mcludes a deflector 230a positioned between a pair of spaced-apart grippers, such as the suction cups 220 shown in. Figures 8 A and 8B.

(0048] The grippers of a gripping sub-assembly 210 pull the web section 16a against a reaction force provided by the deflector 230a. There are two deflectors 230a and 23Gb {one for each gripping sob- assembly).

10049} The deflectors 230a, 230b are disposed between the two rows of suction cups 220, 225 and 226. They limi t the. movement of the web sections 16a and 16b of the laminations 10a and 10b. As the suction cups 220, 225 and 226 pull on the web sections, the deflectors 230a and 230b provide a reaction force. The result of this is that the web portions of the laminations are pulled into a. concave shape (as viewed from the gripping assembly 200), thereby inducing the flanges of the lamination to splay outwardly. This is particularly useful where smaller laminations with shorter flanges are being gripped and stacked. iO SOj hi the embodiments of the invention shown in the drawings, there are two gripping subassemblies, in other embodiments, there may be one or any number of grippin sub-assemblies.

[0051] Also shown in Figures 8A to 8C are laser sensors 240a and 240b. These laser sensors are more clearly visible in Figure 8B, The laser sensors 240a and 240b project hrough slots 231a and 23 lb within deflectors 230a and 23.0b, as shown, in: Figure 8B. The laser sensors measure the position of the webs of the laminations with respect to the sensors themselves (which are fixed to the gripping assembly 200, as is shown in Figures 8A to 8C). The laser sensors assist with the operation of the machine, as is described below.

(0O52| Referring to Figure 4A, 4D and 4E, it can be seen that the stacking station 300 includes a pair of spaced apart web supports 305. The spacin between the web supports 305, most clearly shown in Figure 4B, is variable by means of a lead screw 390 driven by a stepper motor 392, as is shown in Figure 4C,

(0053] The stacking station 300 has left and right pivotable bridges 320 and 340. These bridges are rotatable from the generally vertical position indicated in Figure 4A to the generally horizontal position sho n in Figures 4B and 4C.

[0054] Now referring to Figures 5, 6, 7 and 8. a nozzle assembly 600 and a nozzle assembly 650 are shown. The nozzle assembly 600 is mounted at the end 129 of the ami 120. As can be seen from Figure 5_» the nozzle assembly 600 includes four nozzles 610, 620, 630 and 640. Nozzles 6.10 and.640 are orientated in substantially one direction and nozzles 620 and: 630 are orientated in substantially a second direction. Each nozzle is individually adjustable. [0655] The nozzle assembly 650 is shown in .Figure 6. This nozzle assembly is mounted to a sub-frame 115. The position of the sub-frame is more clearly shown in Figure 10 which also shows a nozzle 680 of the nozzle assembly 650. Like the nozzle assembly 600, the nozzle assembly 650 includes four .nozzles 660, 670, 680 and 690. Again, each nozzle Is individually adjustable.

[0056] The suction cup 220 and check valve 800 is further illustrated in Figures 9A to 9C. The check valves are in the form of ball seat valve wherein the reaction is dependent on the volumetric flow rate, effectively capping the allowable flow rate by shutting the valve if the flow rate exceeds the pre-set level. As shown in Figures 8 A to 8C, suction cups 220 are fitted with check valves 800. Each check valve can be shut individually when the flow rate exceeds a certain value, preventing a loss of suctio to other cups and dissipation of suction energy.

[0057] Referring to Figures 8A to 8C, it can be seen that suction cups 225 and 226 do not have check valves. These suction cups are continually sucking. In practice, they are positioned such that whenever the gripping assembly is gripping a lamination, they are engaged with the web of the lamination and therefore do not consume excessive amounts of air.

10058 A method of stacking magnetic core laminations that are formed by a lamination forming machine, such as the machine 20 shown in. Figure 1 , will now be described.

{0059} Referring to Figure I, the lamination forming machine 20 receives magnetic strip material from, the coiling machine. The lamination forming machine 20 folds and cuts the strip material as is described in the applicant's earlier PCT Application No. PCT/AU2011/000757 titled "Machine For rnamifacturing laminations for a magnetic core" (the contents of which is hereby incorporated by reference). The machine 20 presents a pair of spaced apart laminations 10a and 10b such that the web sections i 6a and 16b lie in a substantially vertical plane, a is shown in Figure 2A. The gripping assembly 200 of the automated stacking machine 100 is positioned in a gripping orientation adjacent to the web sections 16a and 16b of the presented folded laminations 10a and 10b that is shown I Figure 2B.

[0060] A low pressure zone is induced between the webs of the laminations and the gripping assembly 200 by means of suctio through the suctions cups 220, 225 and 226 of the gripping sub-assemblies 210. Thi results in the gripping assembly 200 gripping the laminations 10a and 1 Ob while the lamination is held in the folding and cutting machine 20 (and prior to a final cut operation).

[00.61] The laser sensors 240a and 240b as shown most clearly in Figure 813, measure the distance between the webs of the laminati on and the. gripping assembly 200, If the distances are out of tolerance, indicating that the gripping assembly has not properly gripped either one or both of the laminations, then s

the gripping assembly is controlled by an automated controller to activate again to attempt to grip the webs of the laminat i ons,

[6062] Referring to Figure 7, air nozzles 700a and 700b (only nozzle 700a is visible in this Figure), are positioned within, the lamination forming machine 20 behind the webs 16a and 16b of the pair of laminations 10a and 10b. The nozzles 700a and 700b direct air streams outwardly, under control of the controller, to stabilise the webs 16a and 1 to further facilitate gripping by the gripping assembly 210.

[0063} Figures 2 and 2D show transportation of the laminations 10a and 10b away from the lamination forming machine 20. During this transportation, the machine 100 is synchronised with the roll feeder of the lamination forming machine 20. This synchronisation or "follow mode" ensures that the movement of the _.gripping assembly 200 away from the lamination forming machine 20 i synchronised with the movement of the lamination induced by rollers within the lamination forming machine 20, To achieve this synchronisation, the linear dri ve assembly 130 includes a servo motor thai is precisely controlled, to synchronise with the rollers of the lamination forming machine 20. During^' this movement, the laser sensors 240a and 240b continue to sense the position of the laminations to ensure that they are held by the gripping assembly 200. Once the laminations are in the position illustrated in Figure 2D, the lamination forming machine 20 performs the final, cut operation cutting the flanges 14a and 14b.

[0064] From the position shown in Figure 2D, the laminations 10a and 10b are rotated about an axis 141 in the direction of an arrow 142 as is shown in Figure 2D transitioning to Figure 3 A. This rotation moves the web sections 16a and 16b from a substantially vertical plane to a substantially horizontal plane above a stacking station 300 as illustrated in Figure 3A. Again, the laser sensors 240a and 240b continue to sense the positions of the webs of the laminations as they are rotated by the rotation drive assembly 140. This is important because the laminations have inertia and are subjected to aerodynamic forces during the operation and, as the machine operates quickly, significant forces are generated that could potentially result in the gripping assembly 200 losing grip on one or both of the laminations. Should this occur, then an alarm is activated and the machine, is shut down by the automated controller.

10065} In practice, the laminations 10a and 10b shown in Figure 3A are deflected by the deflectors 230 and 230b, as shown in. Figures 8 A to 8C. That is, the laminations will not be precisely in the orientation that they are illustrated in Figure 3 A. M ore specifically, the action of the suction cups working against the deflectors causes the flanges of the laminations to tend to splay outwardly more than they otherwise would. This works against the tendency for the flanges to collapse inwardly under gravity. For smaller laminations, this deflection is of greater importance, whereas for larger laminations with longer flanges, the effect of the nozzle assembly 600 arid 650 is more important, as is described below. [W66| Referring to figure 3 A, the laminations 10a and 10b can be released onto the stacking receiving arms 305 of the stacking station 300 relatively easily. However, once a first pair of laminations 10a and 10b have been positioned on the stacking station 300, it is more difficult to release a subsequent lamination onto the first lamination. This is because the unsupported flanges of the laminations may tend to sag towards each other or to flap. That is, in practice, the flanges 12a, 12b, 14a and 14 b as shown in. Figure 3A tend to be quite mobile and do not sit rigidly in the positio shown in Figure 3 A. This may cause the flanges to collide with the first lamination such that a neat stack is not achieved. This problem is solved by splaying the flanges outwards away from each other using an air stream. The air stream is induced by sets of nozzles most clearly illustrated in Figures 5 and 6,

{0Θ67] Referring to figure 5, it can be seen that nozzles 620 and 630 are directed in a first general direction and nozzles 640 and 610 are directed in a second general direction. The first and second directions are very roughly at right angles to each other (or the first and second directions are separated by at least 45 degrees). The first general direction is directed towards a flange 12a of the lamination 10a and the second general direction is directed to a second flange 14a of the lamination 10a, Compressed air flowing out of the nozzles has the effect of splaying the flanges 12a and 14a and 12 b and 14b, as is shown most clearly in Figures 3B and 3C. The air stream also has the effect of stabilising the flanges such that laminations stacking can reliably and repeatedly occur at a reasonable speed.

10068] With the flanges separated and supported by the air streams as described, the gripping assembly 200 slides downwardly under the action of the linear drive assembly 130 from the upper position shown in Figures 3a and 3b to the lower position shown in Figures 3C and 3D,

{0069} Once in the position shown in Figure 3C, the suction is removed from the gripping subassemblies 210 and the laminations 10a and 10b travel onto the stacking station 300 to the position shown in Figure 3D, The movement of the laminations 10a and 10b onto the stacking station 300 is assisted by both gravity and a small air blast through the suction cups. The suction induced by the suction cups 220, 225 and 226 is turned off prior to the small air blast, f_;Q070j As the lamination stacks increase in height, the vertical position in which the gripping assembl releases the lamination varies to maintain the distance in which each lamination travels upon release. The laser sensors 240a and 240b sense the height of the stack and compare the sensed height witli the predicted height. If the sensed height is outside of a pre-set tolerance, then tills is likely to indicate that there has been a mis-stacking. For instance, it may indicate that a flange of a lamination has befit upwards towards or even against a web portion. The machine then alarms and can. shut down. Next, the gripping assembly 200 is actuated upwards by the linear drive assembly 130 and is then rotated by the rotation drive assembly 140 to the positions shown in Figure 3E. f0071] The above described steps are repeated numerous times until a pair of lamination stacks 910 and 920 are fanned. The lamination stacks are then rotated through approximately 90 degrees from the positions shown in Figure 4A to the position shown in Figure 4B. This is achieved through rotation of the left and right pivotable bridges 320 and 420 down towards left and right conveyors 410 and 420 respectively.

[0072] Referring to Figures 4A and 4C, the mechanism- for driving the rotation of the left and right pivotal bridges 320 and 340 down towards the left and right conveyors 410 arid 420 is shown.

Specifically. Figure 4A shows a pair of spaced apart cylinders 332 connected to a crossbar 333. The crossbar 333 is connected to a pair of spaced apart racks 330. The racks 330 drive pinions 331 , which are connected for rotation with bridge 320. A mirror image arrangement is provided to drive the bridge 340.

[00731 Once the lamination stacks 910 and 920 are in a position shown in Figure 4B, they are ejected by stack ejectors 323 and 343 (visible in Figure 4C) and then they roll away, as shown in Figure 4C for further processing and assembly into a transformer core.

[0074] Throughout the specification and the claims that follow, unless the context -requires otherwise, the words "comprise" and '' include" and variations such as "comprising" and "including" will be ^'understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of mtegers.

[0075] The reference to any prior art in this specification is not, and should not. be taken as, an.

acknowledgement of any form of suggestion- that such prior art forms part of the common genera! knowledge,

[0076] It will be appreciated by those skilled in the art thai the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein, it will be appreciated that, the invention is not limited to the embodiment or embodiments disclosed, but is capabls of numerous rearrangements, modifications and substitutions without departing from "the scope of the invention as set forth and defined by the following claims,

(0877J The following claims are provisional claims only,, and are provided as examples of possible claims and are not intended to limit the scope of what may be claimed in any future patent applications based on the present application. Integers may be added to or omitted from the example claims at a later date so as to further define or rc-defme the invention.

Claims

1. An automated machine for stacking magnetic core laminations thai are formed having a web section and unsupported flanges extending from outer edges of the web section, the automated machine

including:

a frame

a pivotahle ami mounted to the frame; and

a lamination gripping assembly slidably movable along the arm, the gripping assembly having at least one gripping element for reieasabiy gripping the web section of an individual lamination, wherein, the aim and gripping assembly are operabl movable between a gripping orientation and a stacking orientation,

2. The automated machine as claimed in claim 1 wherein the gripping assembly includes a deflecting assembly, the deflecting assembly including a deflector positioned between a pair of spaced-apart gripping elements,

wherein the gripping elements pull the web section against a reaction force provided by the deflector.

3. The automated machine as claimed in claim 2 wherein the deflector assembly includes a body defining an aperture,

4. The automated machine as claimed in claim 3 including a sensor assembly, the sensor assembly for sensin a distance between the web section and a portion of the sensor assembly.

5. The automated machine as claimed in claim 4 wherein the sensor assembly produces a laser beam, in use the beam, passing through the aperture in the body of the deflector,

6. The automated machine as claimed in claim 1 wherei the gripping assembly includes at least two suction cups.

7. The automated machine as claimed in claim 6 wherein the gripping assembly includes two rows of suction cups.

8. The automated machine as claimed in claim ί including:

a linear drive assembly for sliding the gripping assembly along the arm; and

a rotational drive assembly for rotating the gripping assembly with respect to the arm,

9. The automated machine as claimed in claim 8 wherein the linear drive assembly includes a first servomotor.

10. The automated machine as claimed in claim 8 wherein the rotational drive assesttbiy includes a second servomotor.

1 L The automated machine as claimed in claim 1 wherein the gripping assembly includes two adjacent gripping sub-assemblies.

12. A method of stacking magnetic core laminations- that are formed by a lamination forming machine, the laminations having a web section and unsupported flanges extending from outer edges of the web section, the method including the steps of:

(1) presenting a folded lamination saeh that a web section lies in a substantially vertical plane;

(3) gripping the lamination with the gripping assembly;

(4) transporting the lamination away from the lamination forming machine;

(5) rotating the lamination such that the web sectio lies in a substantially horizontal plane above a stacking station: and

(6) releasing the lamination onto the stacking station.

13.. A method as claimed in claim 12 including the step of splaying the flanges outwardly, wherein the splaying step occurs prior to the releasing step.

14. A method as claimed in claim 13 claim wherein the step of splaying occurs during tire step of gripping.

15. A method as claimed in claim 14 wherein the ste of gripping the lamination takes place while the lamination is held in a folding and cutting machine and prior to a final cut operation.

16. A method as claimed in claim 15 wherein the step of gripping the lamination includes:

creating a low pressure zone between the web section of the lamination and the gripping assembly by means of suction.

17. A method of stacking laminations having a web section and unsupported flanges extending from outer edges of the web section, the method including the steps of:

positioning a first■ lamination such that its web lies substantially horizontal with its flanges lying substantially vertical;

gripping the web section of a subsequent lamination;

splaying the flanges of the subsequent lamination outwards and away from each using a deflector positioned between a pair of spaced-apart grippers and

releasing the subsequent lamination onto the first lamination.

18. A method of stacking l aminations having a web section and unsupported flanges extending from outer edges of the web section, the method including the steps of:

gripping the web section of a subsequent, lamination;

splaying the flanges of the subsequent lamination outwards and away from each other using an air stream; and

releasing the subsequent lamination onto the first lamination.

19. The method as claimed in claim 18 wherein the air stream is induced by compressed air Sowing out of a set of nozzles,

20. The method as claimed in claim 19 wherein the set of nozzles include at least a first and a second nozzle, the first nozzle directing air in a first direction and the second nozzle directing air in a second direction, the first and second directions separated by at least 45 degrees.

21. The method, as claimed in claim 20 wherein the first and second directions are separated, by about .90 degrees.