Method and device for producing sheet metal parts

Abstract

The invention relates to a method for producing sheet metal parts (20), in particular for producing electrical sheets for electric motors and / or generators, by high-speed shearing, wherein the sheet metal parts (20) are produced by high-speed shearing from a sheet stack (22) of at least two superimposed sheets (24). Furthermore, the invention relates to a device (10) for producing sheet metal parts (20), in particular for producing electrical sheets for electric motors and / or generators, comprising a high-speed shearing unit (12), wherein the high-speed shearing unit (12) is designed to produce the sheet metal parts (20) by high-speed shearing from a sheet stack (22) of at least two superimposed sheets (24).

Description

Prior ArtThe invention relates to a method and a device for producing sheet metal parts, in particular for producing electric sheets for electric motors and / or generators.DE 10 2007 019 911 A1 discloses a method and a device for producing sheet metal parts, wherein the sheet metal is separated by high-speed shear cutting using the adiabatic effect.Disclosure of the InventionAdvantages of the InventionThe method according to the invention for producing sheet metal parts, in particular for producing electric sheets for electric motors and / or generators, by high-speed shear cutting, wherein the sheet metal parts are produced by high-speed shear cutting from a sheet metal stack of at least two sheets lying one above the other, has the advantage, in contrast, that a high production throughput can be achieved in the production of sheet metal parts with simultaneously high-quality sheet metal parts which have planar separating surfaces, have a low deformation, have a high dimensional stability and are low in burr. In particular in the production of electric sheets for electric motors and / or generators with electric sheets having thin-walled structures, the method contributes to minimal edge deformations. In particular, a through-connection between electric sheets in the laminated core is minimized, so that the losses in the electric motor are minimized. Furthermore, the method contributes to producing thinner structures of the metal sheets efficiently, so that losses in the electric motor are likewise minimized as a result. Also, the lamination of the laminations is improved by minimizing the degree due to high speed shear cutting.A method is particularly advantageous in which the sheet metal parts are produced by high-speed shear cutting from a stack of sheets of at least 5, in particular exactly 5, sheets lying one above the other, in particular of at least 10 sheets lying one above the other, particularly preferably of 2 to 10 sheets lying one above the other, in particular of at least 20 sheets lying one above the other. The sheets preferably have a sheet thickness of from 0.1 mm to 1 mm. The sheet metal stack preferably has a sheet metal stack thickness of between 0.2 mm and 5 mm. This contributes firstly to a high throughput and furthermore to a high quality of the bleaching parts. The laminated cores also allow realistic cutting gaps because the sheet thickness in the sheet stack is correspondingly high. This leads to low production costs of the tool or the cutting edge.A method is advantageous in which the sheet metal parts are produced as semifinished products by punching from a sheet metal stack of at least two sheets lying one above the other in a method step preceding the high-speed shear cutting and / or in a method step following the high-speed shear cutting, and the semifinished products consisting of at least two sheets lying one above the other are post-processed or processed by the high-speed shear cutting. A method is advantageous in which cut edges of the semi-finished products formed by the punching, comprising the sheet stack of at least two sheets lying one above the other, are remachined by the high-speed shear cutting. Alternatively or additionally, a method is advantageous in which the semi-finished products, comprising the sheet stack of at least two sheets lying one above the other, are processed outside the cut edges produced by the punching by the high-speed shear cutting. The use of high-speed shear cutting with a punching process upstream or possibly downstream likewise contributes to a high throughput in the production of the sheet metal parts.High-speed shear cutting is characterized in that high-speed shear cutting is performed at a shear speed at which cutting is performed by utilizing the adiabatic effect. The adiabatic effect is understood to mean that, due to the high speeds of gravity, the heat generated by the cutting cannot flow away from the shear zone, so that the short-term heating prevailing in the shear zone leads to a drop in the yield stress. Preferably, the shear speed of the high-speed shear cutting is between 1 and 100 meters per second, in particular between 1 and 20 meters per second, preferably more than 5 meters per second, in particular more than 10 meters per second.The invention further relates to a device for producing sheet metal parts, in particular for producing electric sheets for electric motors and / or generators, comprising a high-speed shear cutting unit, wherein the high-speed shear cutting unit is designed to produce the sheet metal parts by high-speed shear cutting from a sheet stack of at least two sheets lying one above the other. In particular, the apparatus comprises at least two sheet metal rollers and a sheet metal stack unit, wherein the sheet metal stack unit is configured to produce a sheet metal stack of at least two sheets from at least two sheets of the at least two sheet metal rollers. Preferably, the at least two sheet metal rollers are arranged one above the other and / or one behind the other. In particular, the device comprises a sheet-metal stamping unit, wherein the sheet-metal stamping unit is configured to produce sheet-metal parts from a sheet-metal stack of at least two sheets lying one above the other by stamping as semifinished products. Preferably, the at least two sheet metal rollers, the sheet metal stack unit, the optional sheet metal punching unit and the high-speed shear cutting unit are arranged sequentially one behind the other in a feed direction of the sheet metal stacks. Particularly preferably, the device is designed or comprises means for carrying out the method described above.The advantages mentioned for the method apply correspondingly to the described device.Further advantages result from the following description of exemplary embodiments with reference to the figures and from the dependent claims.Brief Description of the DrawingsExemplary embodiments of the invention are illustrated in the drawings on the basis of a plurality of figures and are explained in more detail in the description which follows.The following are shown: FIG. 1 is an overview diagram of a device for producing sheet metal parts, FIG. 2 shows a device for producing sheet metal parts in a first variant, FIG. 3 shows a device for producing sheet metal parts in a second variant, and FIG. 4 shows a flow diagram of a method for producing sheet metal parts.DESCRIPTION OF EMBODIMENTSA method for producing sheet metal parts is described below, in particular for producing electric sheets for electric motors and / or generators, by high-speed shear cutting, wherein the sheet metal parts are produced by high-speed shear cutting from a sheet metal stack of at least two sheets lying one above the other. Furthermore, a device for producing sheet metal parts is described, in particular for producing electric sheets for electric motors and / or generators, comprising a high-speed shear cutting unit, wherein the high-speed shear cutting unit is designed to produce the sheet metal parts by high-speed shear cutting from a sheet stack of at least two sheets lying one above the other.Sheet metal parts which demand a rough quality, for example have rough geometric tolerances and / or permit burr and / or local material deformation are stamped out of the sheet metal stack without the use of high-speed shear cutting. The parts of the sheet metal parts with high quality requirements are produced precisely and with low burring from the pre-punched stack of sheets by means of high-speed shear cutting units. In this case, such locations can be pre-punched in preceding sheet metal punching units, so that only fine post-processing takes place in the high-speed shear cutting units with high-speed shear cutting. Alternatively, methods and sheet metal parts are possible in which, in particular exclusively, high-speed shear cutting is used.FIG. 1 shows an overview diagram of a device 10 for producing sheet metal parts. The device 10 comprises a high-speed shear-cutting unit 12. The high-speed shear-cutting unit 12 is designed to produce sheet metal parts by high-speed shear-cutting from a sheet metal stack of at least two sheets lying one above the other. For this purpose, the high-speed shear cutting unit 12 comprises a feed unit, wherein the feed unit is configured to feed a sheet stack of at least two sheets lying one above the other to the high-speed shear cutting unit 12. The high-speed shear cutting unit 12 is configured to perform the high-speed shear cutting such that the high-speed shear cutting is performed at a shear speed at which cutting is performed using the adiabatic effect. Preferably, the high-speed shear cutting unit 12 is configured to cut at a shear speed between 1 and 100 meters per second, in particular between 1 and 20 meters per second. In the preferred exemplary embodiment, the high-speed shear-cutting unit 12 is designed to cut out the sheet metal parts by high-speed shear-cutting from a sheet metal stack of at least five sheets lying one above the other, in particular of at least 10 sheets lying one above the other, particularly preferably of at least 20 sheets lying one above the other. The apparatus 10 further comprises at least two sheet metal rollers 16 and a sheet metal stack unit 14, wherein the sheet metal stack unit 14 is configured to produce a sheet metal stack of at least two sheets from at least two sheets of the at least two sheet metal rollers 16. Optionally, the device 10 comprises a sheet-metal stamping unit 18, wherein the sheet-metal stamping unit 18 is configured to produce sheet-metal parts from a sheet-metal stack of at least two sheets lying one above the other by stamping as semifinished products. In the presence of a sheet metal blanking unit 18, the punched sheet metal stacks are remachined by the high-speed shear cutting unit 12. In a first variant, it is provided that the high-speed shear cutting unit 12 is formed which processes the cut edges of the semi-finished products formed by the preceding punching, comprising the sheet stack of at least two sheets lying one above the other. In a second variant, the high-speed shear cutting unit 12 is alternatively or additionally configured to process the semi-finished products, comprising the sheet stack of at least two sheets lying one above the other, outside the cut edges produced by the punching by the high-speed shear cutting. In one variant, it is provided that the sheet metal punching unit 18 is arranged after the high-speed shear cutting unit 12, so that firstly the sheet metal stack is processed with the high-speed shear cutting unit 12 and then the sheet metal parts are punched out of the sheet metal stack by the sheet metal punching unit 18.FIG. 2 shows a device 10 for producing sheet metal parts 20 in a first variant. The device 10 comprises a plurality of sheet metal rollers 16 with sheets 24 rolled up thereon. The sheets 24 of the sheet metal rollers 16 are fed to a sheet metal stack unit 14, wherein the sheet metal stack unit 14 is designed to produce a sheet metal stack 22 from the fed sheets 24. The stack of sheets 22 is continuously fed to the high speed shear cutting unit 12. The high-speed shear cutting unit 12 comprises at least one cutting edge 26 for high-speed shear cutting of the sheet metal stack 22, and the sheet metal parts 20 shear-cut from the sheet metal stack 22 are collected in a collecting container. The punching movement 30 of the cutting edge 26 is characterized in FIG. 2 and guides the cutting edge 26 substantially perpendicularly onto the sheet stack 22, The high-speed shear cutting unit 12 is configured to move the cutting edge 26 during shear cutting at a shear speed, such that cutting takes place using the adiabatic effect, in particular such that the shear speed is between 1 and 100 meters per second. The feed direction 28 of the sheet stack 22 is marked and leads from the sheet rolls 16 via the sheet stack unit 14 and the high-speed shear cutting unit 12.FIG. 3 shows a device 10 for producing sheet metal parts 20 in a second variant. The device 10 of the second variant corresponds to the device 10 of the first variant, except for the arrangement of the sheet metal rollers 16. In this second variant, the sheet metal rollers 16 are arranged one behind the other. FIG. 3 moreover shows a sheet-metal stack unit 14 for producing a sheet-metal stack 22, a high-speed shear-cutting unit 12 having a cutting edge 26 for shear-cutting the sheet-metal parts 20 from the sheet-metal stack 22, The punching movement 30 of the cutting edge 26 and the feed direction 28 of the sheet-metal stack 22 are indicated in FIG. 3. Otherwise, reference is made to the description relating to FIG. 2.FIG. 4 shows a flow diagram of a method for producing sheet metal parts, in particular by means of the device described with reference to FIGS. 1 to 3. In a first method step 40, metal sheets from metal sheet rolls are made available. In a second method step 42, sheet metal stacks are produced from the sheets made available. In an optional third method step 44, sheet metal parts are punched out of the stack of sheets. In a fourth method step 46, sheet metal parts are produced from the stamped out sheet metal parts and / or the sheet metal stack by high-speed shear cutting. In a variant of the method, the fourth method step is carried out first and then the third method step is carried out.In a variant of the preferred exemplary embodiment, the sheets are not provided via sheet metal rollers, but rather as sheet metal panels which are provided by a sheet metal stack unit as a sheet metal stack for the further method steps, in particular the high-speed unit and / or the sheet metal punching unit.The use of the invention can be proven on the sheet metal parts produced, since the stacking processing of the sheets, in particular of electric sheets, leaves behind characteristic patterns in the sheet metal parts and their shear interfaces. By this pattern, the stacking work and the high-speed shearing can be detected.The method and the device described are preferably used for producing stator and / or rotor packs of electric motors and / or generators in the automotive sector and / or in the industrial sector.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2007 019 911 A1

[0002]

Claims

Method for producing sheet metal parts (20), in particular for producing electric sheets for electric motors and / or generators, by high-speed shear cutting, characterized in that the sheet metal parts (20) are produced by high-speed shear cutting from a sheet metal stack (22) of at least two sheets (24) lying one above the other.Method according to Claim 1, characterized in that the sheet metal parts (20) are produced by high-speed shear cutting from a sheet metal stack (22) of at least 5 sheets (24) lying one above the other, in particular of at least 10 sheets (24) lying one above the other, particularly preferably of between 2 and 10 sheets (24) lying one above the other, in particular of at least 20 sheets (24) lying one above the other, wherein the sheet metal stack (22) preferably has a sheet metal stack thickness of between 0.2 mm and 5 mm.Method according to one of the preceding claims, characterized in that the sheet metal parts (20) are produced in a method step preceding the high-speed shear cutting and / or in a method step following the high-speed shear cutting from a sheet metal stack (22) of at least two sheets (24) lying one above the other by punching as semifinished products, and the semifinished products consisting of at least two sheets (24) lying one above the other are post-processed or processed by the high-speed shear cutting.Method according to Claim 3, characterized in that cut edges of the semifinished products produced by the punching, comprising the sheet stack (22) of at least two sheets (24) lying one above the other, are remachined by the high-speed shear cutting.Method according to claim 3, characterised in that the semi-finished products comprising the sheet stack (22) of at least two sheets (24) lying one above the other are processed outside the cut edges produced by the punching by the high-speed shear cutting.Method according to one of the preceding claims, characterized in that the high-speed shear cutting is carried out in such a way that the high-speed shear cutting is carried out at a shear speed at which cutting is carried out using the adiabatic effect.Method according to one of the preceding claims, characterized in that the shear speed of the high-speed shear cutting is between 1 and 100 metres per second, in particular between 1 and 20 metres per second.Device (10) for producing sheet metal parts (20), in particular for producing electric sheets for electric motors and / or generators, comprising a high-speed shear-cutting unit (12), characterized in that the high-speed shear-cutting unit (12) is designed to produce the sheet metal parts (20) by high-speed shear-cutting from a sheet stack (22) of at least two sheets (24) lying one above the other.Device (10) according to claim 8, characterised in that the device (10) comprises at least two sheet metal rollers (16) and a sheet metal stack unit (14), wherein the sheet metal stack unit (14) is designed to produce a sheet metal stack (22) of at least two sheets (24) from at least two sheets (24) of the at least two sheet metal rollers (16).Device (10) according to claim 9, characterised in that the at least two sheet metal rollers (16) are arranged one above the other and / or one behind the other.Device (10) according to one of Claims 8 to 10, characterized in that the device (10) comprises a sheet-metal stamping unit (18), wherein the sheet-metal stamping unit (18) is designed to produce sheet-metal parts (20) from a sheet-metal stack (22) of at least two sheets (24) lying one above the other by stamping as semifinished products.The device (10) according to any one of claims 8 to 11, characterized in that the at least two sheet metal rollers (16), the sheet metal stack unit (14), the optional sheet metal punching unit (18) and the high-speed shear cutting unit (12) are arranged sequentially one behind the other in a feed direction (28) of the sheet metal stacks (22).Device (10) according to one of Claims 8 to 12, characterized in that the device (10) is designed to carry out the method according to one of Claims 1 to 7.

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