EP0843881B1 - Process and device for bundling laminations, in particular for producing transformer cores - Google Patents

Description

The invention relates to a method for layering laminated cores, especially for the production of transformer cores according to the preamble of claim 1, and one Device for layering such laminated cores according to the Preamble of claim 8.

Methods and devices of this type have been around since long known and in use. An example of a corresponding Workstation is described in EP-A 184 563. A transformer core is placed on a stacking table piled up by means of a transportable Gripping device stored individual sheets and immediately at the shelf. The gripper picks up the individual sheets of stockpiles, which can be moved Storage tables in the effective area of the gripping device can be pushed.

A method has become known from DE-A-3535 573 in the transformer cores in one device continuously getting produced. The core sheet material is used fed continuously from a roll and with the help of a punching tool punched out. The material thickness is before the cutting process electronically determined by a measuring device. The punching tool a metering device for adhesive is also assigned. The cores are glued continuously and simultaneously Eject through the cutting plate into one Work magazine. When the required core strength is reached the glue supply is interrupted once so that the Production of a new core begins. This method is not suitable for the production of large areas and complicated cores with several individual parts.

The gluing of the individual core sheets is also through the BE-A-694 510 became known. The individual sheets are included coated with an adhesive that only under elevated Temperatures is activated. EP-A-10 654 describes a Process for gluing laminated core in transformer construction, where the laminated cores only after layering poured over a casting resin. However, this penetrates the micro-fine spaces between the individual sheets one and the sheets are glued together in this way.

There is a problem with layering transformer cores in that the laminated cores to be layered in cross section are built up in stages, that several legs against each other have to be posted and that finally to Increasing the efficiency of the individual layers must be arranged to each other. So that at rein manual stratification high demands on the worker posed. Automation of the work process requires on the other hand, a large expenditure on equipment that is insufficient Utilization causes disproportionately high costs.

In the previous methods and devices, the complete layering of a finished laminate, so for example a finished transformer core on the sought at the same shift station. Until the delay The laminated body is not stabilized and must be wound to be handled with care. Warehousing finished laminate is therefore relatively difficult. In many However, in cases it would be desirable to have either finished laminates easy to store, or just to manufacture individual components of a laminated body in stock and only at a later time to a finished one Assemble laminate. It is therefore a task the invention, a method of the type mentioned create that easily building compact Sheet metal packages, which can be easily transported and can be stored. The laminated core should be mechanical should be stabilized and should be used in one Transformers core an improvement in electrical Properties can be achieved.

This task is done with solved a method having the features in claim 1.

Surprisingly, it has been shown that gluing the Single sheets within a sheet stack have several advantages causes. Regardless of whether the actual layering process can be done manually or automatically, the finished Sheet pack at the end of the shift process without any special precautions be transported and stored. There is not the risk of a previously built up offset between individual layers or between individual layers again shifts. The bending stability of a laminated core is significantly improved by the bonding, which is particularly advantageous in the case of long laminated cores. The adhesive layer between the individual sheets leads to a transformer core on the one hand to an improvement of the electrical properties because the glue acts as an insulator works and on the other hand to a reduction of the transformer noise, because the individual sheets cannot swing.

A single sheet is always stored in the correct position and held down in the dropped position. Subsequently the adhesive is applied to the surface of the deposited single sheet applied and another single sheet on the with Adhesive-coated surface deposited. The process will repeated until the laminated core is set up. The Holding down on the one hand causes the last one to be dropped Sheet is pressed against the previous sheet and that the adhesive in between is distributed correctly. On the other hand, it also prevents the Apply the new layer of adhesive to the deposited sheet can move.

It is between the facing side surfaces of the Single sheets before stacking on one or more Put a liquid or paste user glue introduced. In this form, the adhesive can be relatively easy to check for quantity and placement. Especially the adhesive is advantageously punctiform or applied in a linear manner to at least one side surface, that when placed on top of each other a full-surface distribution of the adhesive. Distributed by capillary action the adhesive spreads over the entire surface of a Single sheet without exiting at the front and without leaving any unglued areas. The amount and the arrangement of the dosage can be empirical or calculated be determined.

To join individual sheet metal packages on the front lighten it, it is particularly advantageous if at the ends the individual sheets thus left out an adhesive-free zone will that superimposed ends relative to each other are bendable. The ends can then be particularly light interlocked to be pushed together by the ends slightly bent up on one side.

This can automate the shifting process that the individual sheets on a longitudinal conveyor be brought up and with a first transverse means of transport transferred to a positioning table, where they are in a relative position corresponding to the stack position be positioned so that the positioned individual sheets with a second cross conveyor from the positioning table a stacking table where they are sequentially transferred to the Sheet package are glued and that the finished sheet package transferred to another means of transport for transportation away becomes. Upstream of the positioning table relieves the burden the gluing process from the need for simultaneous Positioning. Only on the stacking table glued, the relative position of each individual sheet already on the positioning table has been set. So can also be relative complicated sequences with different staggered Individual sheets can be glued quickly. To be a homogeneous To ensure bonding, it is advantageous if that assembled laminated core after the gluing process during a predetermined rest time is pressed together. Depending on the Properties of the adhesive used must have this rest period longer or shorter.

You can use an adhesive that is already at Room temperature cures. The sheet pack has without further operations at the end of the rest period its final Stability. In certain cases, an adhesive can also be used be used that does not harden at room temperature, the curing only after the assembly of the laminated core or at a later time in an oven. To readjustments may be necessary for curing the relative position between the individual sheets is still conceivable.

For layering transformer cores with several stages or layers, it is particularly advantageous if individual laminated cores formed for whole or for partial steps or layers and if the individual packages without mutual bonding to be built to the finished core. The final construction of the Single packages only need a little time.

The invention also relates to a device for layering of sheet metal packages, which is a simple implementation of the described method allows.

This device is characterized by the features in claim 8.

The adhesive dosing device guarantees a constant Apply the adhesive without the layering process is affected. Above the stacking table can also a lowerable hold-down device can be arranged, the can be pressed against the individual sheet lying on top.

To the operator largely from manual work too relieve is a postioning table next to the stacking table arranged, with positioning for a correct position Positioning of each sheet is provided. Between the Positioning table and the stacking table is a cross transport arranged that a detection of a single sheet the positioning table and placing it on the stacking table enables. Suitable positioning means are known to the person skilled in the art already known. It can be a threading bolt which engages in an opening in the individual sheets. Alternatively pushing devices are also conceivable which are connected to the Outside edges of a single sheet are pushed and the latter slide into the correct relative position. As a means of transport suction pads or magnetic grippers are possible.

Figur 1

eine Draufsicht auf den Kern eines mehrstufigen Dreiphasen-Transformators,

Figur 2

ein Querschnitt durch den Kern gemäss Figur 1,

Figur 3

die Seitenansicht eines verklebten Blechpakets mit verschiedenen Lagen und Schichten,

Figur 3a

ein Detail aus dem Blechpaket gemäss Figur 3,

Figur 4

eine stark schematisierte Draufsicht auf eine Arbeitsstation zum Schichten eines Blechpakets,

Figur 5

eine Seitenansicht der Arbeitsstation gemäss Figur 4, und

Figur 6

das Verkleben eines Einzelblechs in vier Stadien.

An embodiment of the invention is illustrated in the drawings and will be described in more detail below. Show it:

Figure 1

a plan view of the core of a multi-stage three-phase transformer,

Figure 2

2 shows a cross section through the core according to FIG. 1,

Figure 3

the side view of a glued laminated core with different layers and layers,

Figure 3a

4 a detail from the laminated core according to FIG. 3,

Figure 4

2 shows a highly schematic top view of a work station for layering a laminated core,

Figure 5

a side view of the workstation according to Figure 4, and

Figure 6

the gluing of a single sheet in four stages.

1 shows a better understanding of the invention and 2 a multi-stage core 1 known per se for one Three-phase transformer. This consists of one yoke 2 each and 2 ', from one outer leg 3 and 3' and one Middle leg 4. In cross section can be symmetrical Arrangement of two first stages 5 and 5 ', two second stages 6 and 6 'and a third stage 7 can be distinguished. Of course can also be more complicated or simpler Laminates are built up.

Figures 3 and 3a show a laminated core 8, which is for example around the step of a leg or a yoke could act according to Figures 1 and 2. The sheet pack has the entire layer thickness S and is composed of individual sheets 9, which are stacked into individual layers 10. Each layer consists of a layer 11 finished assembled transformer core electrical Avoiding losses at the joints is one thing Position offset 12 between the layers 10 and on the other Layer offset 13 between the layers 11 is provided. There is an adhesive layer 14 between each of the individual sheets 9 if possible arranged over the entire surface.

Obviously, can be used to manufacture a transformer core according to Figures 1 and 2 each individual stage of the yoke 2, 2 'or each leg 3, 3' made separately and at any later time to finish Core to be assembled. This allows a rational Manufacturing technology because several identical stages or packages can be produced one after the other. An excessive one apparatus expenditure for the simultaneous construction of the whole Kerns is not required. Figures 4 and 5 show one largely automated workstation for performing the inventive method. The workstation consists of essentially from a positioning table 18 on the positioning means 20, for example in the form of push-on elements are arranged. Parallel to the positioning table stands a stacking table 19, which is designed as a lifting table is and in the direction of arrow f relative to the contact surface of the Positioning table can be moved. The stacking table has a support bar 27 arranged as a comb surface.

The individual sheets 9 are fed to the work station a longitudinal conveyor 15, which is, for example can be a conveyor belt. A first means of cross transport 16, which is displaceable in the direction of arrow d, is concerned the transport from the longitudinal transport means 15 to the positioning table 18. With the help of a second, in the direction of the arrow e slidable transverse transport means 17, the individual sheets transported from the positioning table 18 to the stacking table 19 become. At least above the stacking table 19 a hold-down device 21 and at least one Dispensing device 22 arranged for the adhesive. The dosing device and the hold-down device are of this type that it moves from a rest position into a Operating position can be brought. Dosing devices, in particular microdosing pumps for the metered application of Adhesives are already from other technical experts Known areas.

For further transport of the glued laminated core 8 a stacking trolley 24 is provided, which is also comb-like Support bar 28 has. These are dimensioned so that they retracted between the support beams 27 of the stacking table can be.

Supplementary aids are clamping plates 25 and 25 ' provided between which a fully glued laminated core can be pressed together. The pressing force is included With the help of tie rods 26 applied.

The description of the layering process below is given below in addition to FIGS. 4 and 5 also FIG. 6 used. From a charging station, not shown here or a single sheet comes from the cross-cutting system 9 in the direction of arrow a on the longitudinal transport means 15 parallel in front of the positioning table 18. The first means of cross transport 16 transports the single sheet in the direction of the arrow b on the positioning table. There are the positioning means activated so that a precise alignment of the single sheet with respect to the central axis and longitudinal position. It can any offset can be made in the longitudinal direction. The single sheet that is precisely aligned in this way is replaced by the second Transverse means 17 in the direction of arrow c on the stacking table 19 or transported to a stack already there. As shown in FIG. 6a, the vacuum suction cups 23 hold the single sheet is parallel to the base. The hold-down device and the dosing device remain in one Rest position in which the feeding of the single sheet is not hindered becomes.

The hold-down device can be lowered at the same time or after lowering the sheet onto the stack take place (Figure 6b). The vacuum suction device 23 of the second transverse transport means can now be raised and already back to the positioning table 18 for receiving a new one Sheet metal can be returned. The hold-down device 21 presses the single sheet just placed against the stack and at the same time, the metering device 22 becomes punctiform an adhesive applied. Also a line job would be conceivable. After all, the glue could also be out Spray nozzles are sprayed (Figure 6c).

Claims (11)

1. A method of laminating plate packs (8). in particular for the production of transformer cores, in which a plurality of individual plates (9) are stacked one upon the other to form at least one compact plate pack (8) and are glued together partially or over their entire surface area at the mutually facing side surfaces, wherein a respective individual plate (9) is set down in the correct position and held down in the set-down position, wherein then a fluid or pasty adhesive is applied at one or more locations to the surface of the set-down individual plate and a further individual plate is set down on to the surface bearing adhesive and wherein the procedure is repeated until the plate pack (8) is formed, characterised in that the operation of setting the individual plates down in the correct position and glueing them is effected on a stacking table (19) and that the relative position of each individual plate, such position corresponding to the stacking position, is established on a positioning table (18) disposed upstream of the stacking table.
2. A method according to claim 1 characterised in that the individual plates are supplied on a longitudinal transport means (15) and transferred by a first transverse transport means (16) on to the positioning table (18), that the positioned individual plates are transferred by a second transverse transport means (17) from the positioning table on to the stacking table. and that the finished plate pack is transferred on to a further transport means (24) to be transported away.
3. A method according to claim 1 or claim 2 characterised in that after the positioning and glueing operation the plate pack formed is compressed for a predetermined rest time.
4. A method according to one of claims 1 to 3 characterised in that an adhesive which sets at ambient temperature is used.
5. A method according to one of claims 1 to 3 characterised in that an adhesive which does not set at ambient temperature is used and that setting is effected in an oven after the plate pack has been formed or at a later moment in time.
6. A method according to one of claims 1 to 5 characterised in that an adhesive-free zone is left at the ends of the individual plates in such a way that ends which are disposed one upon the other can be bent up relative to each other.
7. A method according to one of claims 1 to 6 characterised in that individual plate packs are formed for entire or for partial steps or layers and that the individual packs are formed without mutual glueing to constitute the finished core.
8. Apparatus for carrying out the method according to claim 1, in particular for the production of transformer cores, comprising a stacking table (19) on which a plurality of individual plates (9) can be stacked to form at least one compact plate pack (8), characterised in that arranged above the stacking table (19) is an adhesive metering device (22) which is movable from a rest position which permits an individual plate to be set down into an operative position in which adhesive can be applied to the surface of a set-down individual plate.
9. Apparatus according to claim 8 characterised in that arranged above the stacking table (19) is a downwardly movable hold-down device (21) which can be pressed against the respectively uppermost individual plate.
10. Apparatus according to claim 8 or claim 9 characterised in that arranged beside the stacking table (19) is a positioning table (18) which is provided with positioning means (20) for positioning each individual plate (9) in the correct position, and that arranged between the positioning table (18) and the stacking table (19) is a transverse transport means (17) for engaging an individual plate on the positioning table and setting it down on the stacking table.
11. Apparatus according to claim 10 characterised in that the stacking table (19) is in the form of a lift table which is movable downwardly relative to the support plane of the positioning table.

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