PRODUCING A PRODUCT MADE OF A FLEXIBLY ROLLED STRIP MATERIAL

Abstract

Producing a product from flexibly rolled metallic strip material comprises feeding a flexibly rolled strip material; determining a measured thickness profile of the strip material over the length of the strip material and calculating a desired cutting position for a blank to be produced from the strip material; separating a blank from the strip material in the desired cutting position; rotating the blank depending on the determined measured thickness profile such that the blank is aligned with its thickness profile in a defined processing position which differs from the desired cutting position; processing the blank in the processing position by a processing unit, wherein the blank is processed to form a product.

Claims

1-15. (canceled)

16. A method of producing a product from flexibly rolled strip material, comprising: providing a flexibly rolled strip material of a metallic material having a thickness profile with a variable thickness over a length of the strip material; determining a measured thickness profile of the strip material over the length of the strip material and calculating a desired cutting position for a raw blank to be produced from the strip material depending on the determined measured thickness profile of the strip material and a respective desired thickness profile of the blank to be cut therefrom, and feeding the strip material to the desired cutting position; cutting a raw blank from the strip material in the desired cutting position, the raw blank being arranged in a cut-off position after cutting; rotating the raw blank depending on the determined measured thickness profile such that the raw blank is positioned with its thickness profile in a defined processing position that is different from the cut-off position; and processing the raw blank in the processing position by a processing device, wherein the raw blank is processed into a product.

17. The method according to claim 16, wherein the strip material has a first strip region with a first thickness profile and an adjoining second strip region with a second thickness profile over the length, wherein the first thickness profile and the second thickness profile differ from each another in the strip material, wherein a first raw blank is separated from the first strip region and a second raw blank is separated from the strip material from the second strip region, and wherein the first raw blank and the second raw blank are rotated such that the first thickness profile and the second thickness profile are equally arranged in the processing position.

18. The method according to claim 16, wherein the first raw blank is rotated in a first direction of rotation depending on the measured thickness profile, and the second raw blank is rotated in an opposite second direction of rotation depending on the measured thickness profile.

19. The method according to any claim 16, wherein the raw blank is rotated by 80 to 100, starting from the cut-off position.

20. The method according to claim 16, wherein the processing device comprises a punching tool or a beam cutting tool.

21. The method according to claim 16, wherein the raw blank is separated from the strip material with a length of less than 2500 millimeters and more than 400 millimeters.

22. The method according to claim 16, wherein the raw blank is cut off with a length that is greater than the width of the strip material.

23. The method according to claim 16, wherein the strip material is fed from a buffer device to a measuring device by a feeding device; wherein determining the measured thickness profile comprises continuously measuring the thickness of the strip material by a thickness measuring unit and continuously measuring the length of the strip material by a length measuring unit, while the strip material is being fed, wherein measuring of the thickness in the feed direction of the strip material is carried out upstream the feeding device, and measuring of the length in the feed direction of the strip material is carried out downstream a first feed unit of the feeding device; calculating a feed length for the raw blank to be separated from the strip material on the basis of the determined measured thickness profile and comparing with a respective desired thickness profile of the raw blank; and feeding the strip material to the separating device by the feeding device on the basis of the calculated feed length.

24. The method according to claim 16, wherein the length measuring unit is referenced at a starting point with the thickness measuring unit with respect to the length, wherein the length measuring unit generates trigger signals and transmits them to the thickness measuring unit, with the trigger signals serving as triggers for performing thickness measurements of the thickness measuring unit.

25. The method according to claim 16, wherein the separating device comprises a first feed unit and a second feed unit for feeding the strip material, wherein a fixed first distance is set between the thickness measuring unit and the first feed unit, and wherein a fixed second distance is set between the thickness measuring unit and the separating device, wherein at least one of the first distance and the second distance are measured with an accuracy of up to +/0.2 millimeters.

26. An apparatus for producing a product from flexibly rolled metallic strip material, comprising: a feeding device for feeding flexibly rolled metallic strip material, which has a thickness profile with different sheet thicknesses along a length of the strip material, wherein successive regions of the flexibly rolled strip material correspond to a respective desired thickness profile of a shaped blank to be produced therefrom; a measuring device for determining the thickness of the strip material over the length of the strip material; a separating device for producing individual raw blanks from the flexibly rolled strip material, with the separating device having a distance from a thickness measuring unit of the measuring device which corresponds to at least twice the length of a raw blank to be separated; a rotating device for rotating a separated raw blank into a desired processing position, wherein the rotating device is controllable by an electronic control unit in order to rotate a separated raw blank into the desired processing position depending on the determined measured thickness profile of the raw blank; and a processing device which is designed to produce a product from the raw blank in the processing position.

27. The apparatus according to claim 26, wherein the electrical control unit is configured to determine a first rotational movement from a first strip region with a first thickness profile, and to determine a second rotational movement, which differs from the first rotational movement, from a second strip region with a second thickness profile.

28. The apparatus according to claim 26, wherein the processing device has at least one cutting tool which cuts a shape-cut blank out of the blank.

29. The apparatus according to claim 26, further comprising: a buffer device for temporarily buffering the flexibly rolled strip material; a first feed unit, which is arranged downstream the buffer device in the feed direction of the strip material; at least one length measuring unit for continuously measuring the length of the strip material, wherein the length measuring device is arranged downstream the first feed unit in the feed direction of the strip material; a thickness measuring unit for continuously measuring the thickness of the strip material along the length, wherein the thickness measuring unit is arranged between the buffer device and the first feed unit in the feed direction of the strip material; and a second feed unit, which is arranged downstream the first feed unit and upstream the separating device; wherein the first feed unit and the second feed unit are designed to move the strip material from the buffer device to the separating device in dependence on the thickness measurement and the length measurement.

30. The apparatus according to claim 26, further comprising: a decoiler for unwinding the flexibly rolled strip material and a straightening unit for straightening the flexibly rolled strip material, which are arranged upstream the buffer device, wherein the first feed unit and the second feed unit for the separating device are controlled independently of a feed of the decoiler and the straightening unit.

Description

BRIEF SUMMARY OF THE DRAWINGS

[0030] Preferred embodiments are explained below using the drawing figures. Herein shows:

[0031] FIG. 1a method and/or apparatus for producing a product from flexibly rolled metal strip in a first embodiment;

[0032] FIG. 2a method and/or apparatus for producing a product from flexibly rolled metal strip in a modified embodiment;

[0033] FIG. 3 shows the thickness profile of an exemplary blank which can be produced with the method and apparatus according to FIG. 1 and/or FIG. 2;

[0034] FIG. 4 parts of the apparatus from FIG. 1 in a three-dimensional representation for producing blanks according to FIG. 3;

[0035] FIG. 5 shows the thickness profile of another exemplary blank which can be produced with the method and apparatus according to FIG. 1 and/or FIG. 2;

[0036] FIG. 6 shows the thickness profile of another exemplary blank which can be produced with the method and apparatus according to FIG. 1 and/or FIG. 2;

[0037] FIG. 7 part of the apparatus from FIG. 1 in a three-dimensional representation for producing blanks according to FIG. 6;

[0038] FIG. 8 further optional apparatus components of an apparatus according to the invention schematically in three-dimensional representation.

DESCRIPTIONS WITH REFERENCE TO THE DRAWINGS

[0039] FIGS. 1 to 8 are described together below, with reference to special features of individual figures.

[0040] FIG. 1 shows a process and individual components of an apparatus 2 for producing a product from a flexibly rolled metal strip. The method comprises the steps of providing S1 a flexibly rolled strip material 3, determining S20 a measured thickness profile D3 of the strip material 3 and calculating a desired cutting position for a blank 4 to be cut from the strip material, and feeding 510 of the strip material 3 to the desired cutting position, cutting S30 of the blank 4 from the strip material 3 along a nominal cutting line 32 in the desired cutting position, rotating S40 the blank 4 depending on the determined measurement thickness profile into a defined processing position P50 for further processing, and processing S50 of the blank 4 to the product 5. The associated apparatus components are a feeding device 10, a measuring device 20, a separating device 30, a rotating device 40 and a processing device 50.

[0041] A flexible rolled strip material is understood to be a metal strip that has a variable sheet thickness over its length. A variable sheet thickness profile can be produced by rolling a strip material with a substantially constant starting sheet thickness by rolling with dynamical variation of the roll gap. The strip material is given different thicknesses D3 over the length L3 in the rolling direction. After flexible rolling, the strip material 3 can be wound up into a coil 1 so that it can be fed to the next processing step.

[0042] The feeding device 10 can have one or more feed units 11, by which the strip material is moved in feed direction R3. A feed unit can have two feed rollers between which the strip material 3 is fed through and moved in the feed direction by rotatingly driving the feed rollers 11.

[0043] The measuring device 20 may comprise at least a length measuring unit 21 for continuously measuring the length L of the strip material 3, and a thickness measuring unit 22 for continuously measuring the thickness D3 of the strip material 3 along its length. The calculation of the desired cutting position for the blank 4 to be separated is then carried out depending on the determined measurement thickness profile D3 of the strip material 3 and the associated desired thickness profile of the blank 4 to be cut therefrom. The length measuring unit 21 can comprise a measuring wheel 23, which is in contact with one side of the strip material 3, and optionally a support wheel 24, which is in contact with the opposite side of the strip material 3 as a counter support for the measuring wheel.

[0044] The length measuring unit 21 and the thickness measuring unit 22 can be coupled with each other in a measuring-technical manner. For a reliable maintaining the length reference over the strip length between the thickness measurement 22 on the one hand and the first feed unit 11 and/or the first length measurement 21 on the other hand, a fixed distance A1 is set between the thickness measuring unit 22 and the first feed unit 11. This distance A1 is measured precisely, preferably with an accuracy of up to +/0.2 mm, and maintained during operation of the line. In this way, the length reference between the thickness measurement on the one hand and the feed and/or length measurement on the other hand can be reliably ensured over the entire length of the strip material. During operation of the apparatus 2, the length measuring unit 21 can generate 21 trigger signals B1 and transmit them to the thickness measuring unit 22. Each trigger signal B1 serves as a trigger for a thickness measurement, so that with each trigger signal of the length measuring unit 21 a thickness measuring value is generated and assigned to a corresponding length measuring value. In this way, data sets of pairs of length and thickness values are generated, from which the actual thickness profile of the blank 4 to be cut out of the strip material 3 can be determined.

[0045] The separating device 30 can be selected according to the requirements of the flat product 4 to be separated and can comprise, for example, a cut-to-length shear 31, as shown schematically, or a cut-to-length beam cutting unit, in particular a laser cutting unit. The separation of a raw blank 4 from the strip material 3 is performed along a nominal cutting edge 32 in the desired cutting position P30, into which the strip has been advanced and positioned by the feeding device 10. In particular, the present method and apparatus are used to produce blanks 4 whose longest length L4 is greater than the width B3 of the strip material 3, which corresponds to the width B4 of the blank 4 to be cut off. In particular, it is further provided that blanks 4 with a length L4 of less than 2500 mm, in particular less than 2000 mm, and/or with a length of more than 400 mm, in particular more than 600 mm, are separated from the strip material.

[0046] The distance A2 between the thickness measuring unit 22 and the separating device 30 is preferably at least twice the blank length L4 of the blank 4 to be cut out of the strip material 3. In particular, the distance A2 is at least twice the blank length plus the feed path covered by the strip material 3 during the computing time for a blank 4 to be cut out.

[0047] In particular, the apparatus and/or method is configured such that the thickness profiles determined by the measuring device 20 are compared with the desired nominal thickness profile. The control unit 26 evaluates whether or not the flexible rolled strip 3 meets the required thickness tolerances. From the result of the comparison, the feed length for the strip 3, respectively the blank 4 to be cut out therefrom can be determined. The strip can be divided into regions that are OK (so-called OK parts) and those that are not OK (so-called not OK parts). The position and length of these individual regions in the strip 3 is transmitted by the thickness measuring device 20 to the feeding device 10, which carries out the instructed feeds accordingly and positions the reference edges of the individual feed lengths accurately to the separation point 32 of the separating device 30. The feeding device 10 can transmit the information to the other apparatus components (30, 40, 50) as to whether the feed length has an OK thickness profile or not.

[0048] After the blank 4 has been cut off, it is rotated about a vertical axis A40 in the rotating device 40. The rotating device can be designed and configured to meet the requirements of the blanks to be rotated. For example, the rotating device 40 can comprise a number of suction cups 41, which are attached to a movable carrier 42. Using the rotating device 40, the blank 4 is rotated from the starting position P30 after cutting from the strip 3, in which the blank 4 is still aligned in the direction R3 of strip 3, depending on the measured thickness profile D3 so that it is aligned with its thickness profile D4 in a defined processing position P50. In particular, it is intended that one or more tools of the further processing device 50 are aligned transversely to the strip feed direction R so that the blanks 4 are each rotated by 90 from the cut-off position P30 to the processing position P50.

[0049] After rotating S40, the equally aligned raw blanks 4 are fed to the further processing device 50. The processing device 50 is selected according to the requirements of the product 5 to be manufactured. In an embodiment shown in FIGS. 1, 4 and 7, the device 50 is configured as a cutting device. In the cutting device 50, the edges of the raw blank 4 are cut off in order to produce a shape cut blank 5 with a desired outer contour. According to a possible embodiment, the cutting device 50 can comprise a lower tool part 51 and a movable upper tool part 52. The lower tool part 51 can be positioned and fixed on a table 53. The upper tool part 52 can be attached to a press ram 54 which is movably guided relative to the table 53 via guide bushes 55.

[0050] According to a second embodiment, which is shown in FIG. 2, the processing device 50 includes a cutting and forming tool. The design and function are similar to those of the cutting device described above. Therefore, the same details are marked with the same reference signs as in FIG. 1. The only difference is that in addition to generating the shape cut, the intermediate product is formed into a three-dimensional component 5 in a forming tool. The components produced in this way can also be referred to as press-formed parts or stamped parts. To produce press-formed parts 5, the device 50 can have a combined cutting and forming tool (punching tool) with which the press-formed part is produced in one step. Alternatively, the device 50 can also comprise several processing steps arranged one after the other with respective tools, which are passed through one after the other by the part to be produced. In particular, at least one cutting tool, in which the blank 4 is cut to form the shape-cut blank, and at least one downstream forming tool, in which the shape-cut blank is formed to the press-formed part 5, may be provided.

[0051] Strip material 3 can have alternating strip regions with different or equal, symmetrical or asymmetrical strip thickness profiles D3 over the length L3.

[0052] FIGS. 3, 5 and 6 show different forms of blanks 4 to be produced from strip material 3, wherein FIG. 4 shows a method suitable for processing blanks 4 as shown in FIGS. 3 and 5, and wherein FIG. 7 shows a method suitable for processing blanks 4 as shown in FIG. 6.

[0053] FIG. 3 shows an exemplary blank 4 in the form of a rectangular blank with an asymmetrical thickness D4 over the length L4 of the blank and with end sections of equal thickness. Specifically, the blank 4 has six different sections 7a, 7b, 7c, 7d with different thicknesses D7a, D7b, D7c, D7d starting from the first end, with the first section 7a and the last section 7d at the second end 8 having the same thickness (D7a=D7d). Between every two sections 7a, 7b, 7c, 7d of constant thickness, which can also be called plateaus, a transition section 9a, 9b, 9c of variable thickness is formed, which can also be called ramps. The rectangular blank 4 shown in FIG. 3 is produced by simply cutting the strip material 3, which has been brought to the correct cutting position P30 by the feeding device 10, for example by using a cutting shear 31.

[0054] FIG. 4 shows a corresponding method for the processing of blanks 4 with a sheet thickness profile according to FIG. 3 by an apparatus 2 according to the invention. The different thicknesses D7a, D7b, D7c, D7d=D7a of the blank from FIG. 3 are shown here in simplified form only with a, b, c, a. It can be seen that starting from the separating position P30 the raw blanks 4 are all rotated uniformly in the same direction of rotation R40, in this case counter-clockwise, to the further processing position P50. At the same time, the blank 4 can also be moved in feed direction V40. After the blanks 4 have been rotated, they are all uniformly arranged transverse to the strip feed direction 10, that is with the same orientation of the sheet thickness profiles a, b, c, a. In the cutting or punching tool 50, the rotated blanks 4 are cut in cycles to form cuts 5 with a desired peripheral contour. Parts identified by the control unit as not OK blanks can be ejected and scrapped between the cutting device 30 and the processing device 50. This can be done by the rotating device 40 or a separate ejection device. The OK products 5 can be stacked behind the device 50 by a stacking unit (not shown).

[0055] FIG. 5 shows another embodiment of a rectangular blank 4, which in contrast to FIG. 3 has a symmetrical thickness D4 over the length L4. It can be seen that the thickness D4 of the blank 4 is mirror-symmetrical in relation to a center plane E. The blank 4 shown here can be processed in the same way as the blank shown in FIG. 3 using the process shown in FIG. 4 which is why, to avoid repetition, reference is made to the above description.

[0056] FIG. 6 shows an embodiment of blanks with end sections having a different thickness. For this reason, two successive blank regions 3A, 3B in the strip 3 are arranged mirrored to each other. Over the length L3 of the strip 3, a first strip region 3A, from which a first blank 4A is to be separated, and a second strip region 3B, from which a second blank 4B is to be separated, alternate. Here, the profile of the first strip region for a first blank 4A corresponds to the profile of the strip region for a second blank 4B with regard to the profile shape, but not with regard to the alignment. Furthermore, the blanks 4A, 4B shown here have an asymmetrical thickness profile D4A, D4B over the respective length L4A, L4B. It can be seen that the thickness D4A of the blank 4A in relation to a center plane EAB is mirror-symmetrical to the thickness D4B of the following blank 4B. The blank 4A has, starting from the first end 6A, a first section 7Aa with a first thickness, a second section 7Ab with a second thickness, a third section 7Ac with a third thickness, and a fourth section 7Ad with a fourth thickness different from the first thickness of the first section 7Aa. Between the sections 7Aa, 7Ab, 7Ac and 7Ad, each having a constant thickness along the length, there are transition sections 9Aa, 9Ab, 9Ac and 9Ad with variable thickness along the length. The second blank 4B is accordingly symmetrical to the first blank 4A. The second blank 4B is followed by a first blank 4A, and so on.

[0057] FIG. 7 shows a corresponding method for processing blanks 4A, 4B with sheet thickness profiles according to FIG. 6, wherein the different thicknesses D7a, D7b, D7c, D7d of the blanks 4A, 4B from FIG. 6 are shown in simplified form with a, b, c, d. The rectangular blanks 4A, 4B are separated by means of the separating device 30 through cross-cutting the strip material 3, brought to the correct cutting position 32 by the feeding device 10, and then rotated to the desired position P50. A special feature is that the thickness profiles D4A and D4B differ from each other in that they are not congruent in their arrangement in the strip material. To ensure that the successive first and second blanks 4A, 4B receive the same orientation for further processing, the first and second blanks 4A, 4B are rotated individually by the rotating device 50 according to their respective profile orientation. For this purpose, the first blanks 4A are rotated depending on the measuring thickness profile D4A in a first direction of rotation R40A (counter-clockwise in this case) and the second blanks 4B are rotated depending on the measuring thickness profile D4B in the opposite, second direction of rotation R40B (clockwise in this case). After rotating and positioning in the processing position P50, the first and second blanks with their respective thickness profile are now aligned identically and are therefore uniform. In this alignment, the blanks 4 are fed to the further processing device 50, which can be configured according to one of the above described embodiments.

[0058] With the method and apparatus, blanks 4 with variable thickness profile (Tailor Rolled Blanks), which have different sheet thicknesses at the opposite ends and/or those with an asymmetrical sheet thickness profile, can be produced efficiently and with high production accuracy. The blanks 4, 4A, 4B are correctly aligned before entering the contour cutting tool so that the sheet thickness profile always matches the shape or cutting contour in the tool. The correctly aligned blanks 4 are fed into the following tool 50 and processed there into shaped cuts or press-formed parts. As the blanks 4, 4A, 4B, which have a greater length L4 than width B4 in the rolling direction, are turned before further processing, the feed length of the blanks into and/or through the tool is shortened so that shorter cycle times are achieved overall.

[0059] FIG. 8 shows further optional apparatus components of an apparatus according to the invention in three-dimensional representation.

[0060] An uncoiling and straightening group 60, a buffer device 70 and an example of a downstream feed and separation group 15 are shown. The starting material is a coil 1 of flexibly rolled metal strip which is unwound from a decoiler 61 and then passes through a straightening unit 62 with a plurality of rolls. Between the decoiler 61 and the straightening unit 62, an infeed driver 63 can be provided to pull the strip material 3 from the decoiler and feed it to the straightening unit 62. A take-off roller 64 can be arranged in the processing direction behind the straightening unit 62, which take-off roller 64 transmits a feed force to the strip material 3. The operation of the apparatus components, i.e. the decoiler, infeed driver, straightening unit and take-off roller, can be synchronized with each other via controllers and operated in speed control or torque control mode. Each of the units can be operated individually, i.e. independently of the others, in a generator or motor mode. FIG. 1 shows the torques M61, M62, M63, M64 that can be transmitted from the respective components 61, 62, 63, 64 to the strip material 3.

[0061] In the strip feed direction behind the uncoiling and straightening group 60, a buffer device 70 is provided, which is designed to temporarily store a respective section of strip 3. This decouples a feed movement of the uncoiling and straightening group 60 from a feed movement of the following apparatus components (10-50). The uncoiling and straightening group 60 conveys the strip 3 to the strip buffer 70, which makes the flexibly rolled strip 3 available for further processing in the separation group 15. The conveying and/or unwinding speed of the uncoiling and straightening group 60 can be controlled by a level sensor 71 of the strip buffer 70. The level sensor 71 can, for example, include an ultrasonic sensor or an optical sensor which senses the depth of the strip loop hanging in the strip buffer and transmits a corresponding signal to the controller for the uncoiling and straightening group.

[0062] Behind the buffer device 70, the apparatus components already described above are the feeding device 10, measuring device 20 and separating device 30. In the present embodiment, the feeding device 10 comprises a first feed unit 11 and a second feed unit 12, which are arranged at a distance from each other. Furthermore, the measuring device comprises a further length measuring unit 25 in addition to the thickness measuring unit 22 and the length measuring unit 21. It can be seen that the thickness measuring unit 22 for continuous measurement of the thickness D3 of the strip material 3 is arranged in front of the first feed unit 11, and that the first length measuring unit 21 for continuous measurement of the length L3 of the strip material 3 is arranged behind the first feed unit 11. The second length measuring unit 25 is assigned to the second feed unit 12 and arranged behind same in feed direction R10.

[0063] The two feed devices 11, 12 are operated synchronously and are designed to move the strip material 3 from the buffer device 70 to the separation device 30 in dependence on the thickness measurement and the length measurement. The two feeds 11, 12 each exert a feed force on the strip material to move it. To ensure that the strip material is held flat between the two feed devices 11, 12, the second feed device 12 can be driven with a slight advance relative to the first feed device 11.

LIST OF REFERENCE SIGNS

[0064] 1 coil [0065] 2 apparatus [0066] 3 strip material [0067] 4 raw blank [0068] 5 product [0069] 6 end [0070] 7 section [0071] 8 end [0072] 9 transition section [0073] 10 feeding device [0074] 11 feed unit [0075] 12 feed unit [0076] 13 feed roller [0077] 15 separation group [0078] 20 measuring device [0079] 21 length measuring unit [0080] 22 thickness measuring unit [0081] 23 measuring wheel [0082] 24 support wheel [0083] 25 length measuring unit [0084] 30 separation device [0085] 31 cut-to-length shear [0086] 32 [0087] 40 rotating device [0088] 41 suction cup0 [0089] 42 carrier [0090] 50 further processing device [0091] 51 lower tool part [0092] 52 upper tool part [0093] 53 press table [0094] 54 press ram [0095] 55 guide bushes [0096] 60 uncoiling and straightening group [0097] 61 coiler [0098] 62 straightening unit [0099] 63 infeed driver [0100] 64 take-off roller [0101] 70 buffer device [0102] 71 level sensor [0103] A distance [0104] B trigger signal [0105] D thickness [0106] E level [0107] L length [0108] M torque [0109] P position [0110] R direction [0111] S step