WO2000069582A1

WO2000069582A1 - Method for producing a striplike pre-material made of metal, especially a pre-material which has been profiled into regularly reoccurring sections, and device therefor

Info

Publication number: WO2000069582A1
Application number: PCT/EP2000/004269
Authority: WO
Inventors: Hans-Jörg BAUDER
Original assignee: Hjb Rolling Mill Technology Gmbh
Priority date: 1999-05-12
Filing date: 2000-05-11
Publication date: 2000-11-23
Also published as: EP1183117B1; EP1183117A1; ATE226491T1; AU5212500A

Abstract

The invention relates to a method and device for the production of a striplike pre-material made of metal, using rollers (11,12) in a roll stand (2) defining a roll gap (13) The metal strip (16) is rolled between said two rollers (11,12) in successive segments in two or more rolling steps. Said metal strip (16) is recalled between two successive rolling steps and the recalled section of the metal strip (16) is rolled once again. The method and device are used to produce a pre-material with a very high surface quality and very low thickness tolerances (e.g. for proofs) and to produce a correspondingly precise pre-material with a profiled section, whereby the cross-sectional form thereof does not extend in the longitudinal direction of the metal strip (16) from the beginning to the end of said strip, but is arranged crosswise in relation to the longitudinal direction of the metal strip (16) and reoccurs in successive sections of said pre-material, e.g. for pens. The height of the roll gap can be adjusted for the second application.

Description

Method for producing a strip-shaped primary material made of metal, in particular of such a primary material which is profiled in regularly recurring sections, and the use of a device therefor.

Description:

The invention is based on a method with the features specified in the preamble of claim 1. Such a method is known from DE 195 04 711 C2. It works in such a way that a metal strip is rolled repeatedly, for which it continuously runs through a roll stand from start to finish, the working direction of which is then reversed, so that the metal strip then runs through the roll stand again over its full length, but now in reverse Direction.

From DE-PS 104 875 it is known to roll a profile in a single step for the production of tubes in strip or plate-shaped workpieces. DE 197 04 300 A1 discloses a similar method for producing profiled blanks, in particular body panels. From DE-PS 638 195 a pilgrim step method for producing thin strips from a thick starting workpiece is known. In this process, the starting workpiece is gradually deformed with a high degree of deformation and pushed against the usual rolling direction through the roll gap.

From US 1, 106.172 it is known to roll profiles continuously into a strip with an arrangement of three rolling stands arranged one behind the other.

Coins and medals for collectors are more valuable the higher their surface quality is. Proofs are used to mint coins and medals, which are coin blanks and medal blanks that already have a high-gloss surface. Proofs are punched out of a strip-like material. For the production of the band-shaped primary material, one starts from a primary material which is a few millimeters, e.g. Is 10 mm thick. This material is made into a band of e.g. Rolled 0.5 mm to 2 mm thick. Such a band, the thickness of which is determined by the thickness of the coins and medals to be minted, is the primary material from which the proofs are stamped. It is state of the art to exchange the two rollers for a pair of rollers whose surface has mirror-like gloss before the last roll pass. The mirror high gloss can be created by lapping.

With each roll revolution, the surface quality of the two rolls decreases because the rolling process results in metal abrasion, which contaminates the roll surfaces. Only during the first rotation of the rollers is their surface mirror-bright. Then the surface quality deteriorates from rotation to rotation and with it the surface quality of the rolled primary material deteriorates. After passing through a strip length of approx. 100 to 1,000 coin diameters, the rollers are usually removed and brought back to a mirror finish by lapping. Despite this complex procedure, no proofs with a constant, high surface quality are obtained. The present invention has for its object to show a way how a band-shaped material with a consistently high surface quality can be produced economically.

This object is achieved by a method with the features specified in claim 1 and by a device with the features specified in claim 63. Advantageous developments of the invention are the subject of the dependent claims.

According to the invention, the metal strip is rolled in successive sections, which are shorter than the circumference of the two rolls, in each case between the same two rolls in two or more than two rolling steps, for which purpose the metal strip is retrieved between two successive rolling steps and then the section of the metal strip which has been retrieved is rolled again becomes.

The retrieval of the metal strip makes it possible for the last rolling step to take place in each of the recovered sections of the metal strip between those peripheral sections of the two rolls which have not yet acted on the relevant section of the metal strip in the one or more preceding rolling steps. so that the last rolling step takes place between peripheral sections of the two rolls which have the best surface quality still available, whereas the preceding rolling steps can take place between peripheral sections of the two rolls which have already carried out a larger number of rolling steps and are of poorer surface quality. The surface quality of the strip-shaped primary material finally produced is determined by the surface quality of those peripheral sections of the two rolls which carry out the last rolling step in the section of the metal strip under consideration. With a discontinuous multi-step rolling process according to the invention, it is possible to produce the strip-like primary material with a particularly high and uniform surface quality and with the smallest thickness tolerances, or to produce a primary material with the quality known from the prior art in greater lengths than before without changing the rollers. Thickness tolerances of + 1 μm, repeatability of + 2 μm, roughness depths of only R, = 0.18 μm and center roughness values (Center Line Average, CLA) of only R _a = 0.022 μm have already been achieved (DIN 4762).

In order to be able to carry out at least two rolling steps in a section of the metal strip using the method according to the invention, the circumference of the rolls should be at least twice as long as the length of the sections that are retrieved, the section being retrieved being somewhat larger than the diameter of the sections to be punched out Proofs so that the unavoidable punching waste can be taken into account. If the metal strip is rolled not only in one direction, but sometimes in one direction and sometimes in the other direction, then one can e.g. also proceed in such a way that the metal strip is rolled back and forth a few times between the same sections of the two rolls and the last rolling step is carried out between two peripheral sections of the rolls which were previously used for a smaller number of rolling steps and therefore an even better surface quality have so that in the last rolling step they give the metal strip a surface with an equally good quality.

If the sections of the metal strip are rolled sometimes in one direction and sometimes in the other direction, you also get a cheaper material structure than if you only rolled the metal strip in the same direction. This is all the more important, the greater the reduction in the thickness of the metal strip caused by the rolling, because the material displacement caused by the rollers also becomes stronger. Another advantage is that the favorable influence on the material structure in sections reciprocating rollers is cheaper than if, as in the prior art, a metal strip is rolled in full length alternately in one and the other direction.

The roller diameter is preferably selected so that at least ten, preferably at least fifteen, proofs can be punched out from a part of the primary material, the length of which corresponds to the circumference of the rollers.

The stepwise repeated rolling of the relevant section of the metal strip is preferably carried out in such a way that of the surface sections of the two rolls which act on the relevant section of the metal strip, the surface sections of the two rolls acting on the relevant section of the metal strip in the first rolling step have the greatest number and the sections of the rolls acting on the relevant section of the metal strip in the last rolling step have carried out the smallest number of rolling steps, the surface quality naturally being best when the section of the rolls acting in the last rolling step executes a rolling step for the first time, that is to say still shows ideal mirror high gloss.

Because a discontinuous multi-step rolling process is carried out and the surface section of the rolls acting in the last rolling step has the highest surface quality, but the surface of the primary material has already been optimally prepared in the previous rolling steps, a longer length can be achieved when the discontinuous multi-step rolling process according to the invention is carried out Pre-material is generated before the rollers have to be removed and lapped back to a mirror finish.

The method according to the invention also works more economically than the known method for producing proofs. The number of rolling steps used to act on one and the same section of the metal strip is matched to the desired stitch reduction and surface quality of the primary material to be produced.

To carry out the method according to the invention, a roll stand with a first reel arranged on the inlet side of the roll nip is suitable for the metal strip to be rolled and with a second reel arranged on the outlet side of the roll nip for winding up the strip-shaped primary material, for those on the inlet side of the roll nip provided reel a drive motor is provided which enables the metal strip to be retrieved in steps of a predeterminable length, in particular a servo motor. The length of the steps by which the metal strip is retrieved can be adapted to the requirements by means of an electronic drive control, in particular program-controlled. With such a program control, the discontinuous drive of the rolls with forward turning, standstill and possibly with backward turning can be optimally adapted to the individual rolling task.

A great advantage of the invention is that it can be applied to other applications. One application relates to the production of metal strips which have grooves which do not extend in the longitudinal direction from the beginning of the strip to the end of the strip, but instead extend from one longitudinal edge to the other longitudinal edge across the entire width and in the metal strip at intervals to return. Such grooved metal strips can be used, for example, to produce contact springs or spiral-wound blades for electric motors, in particular for servo motors, by dividing the metal strips. Advanced servomotors are getting faster and more accurate. This places increasing demands on the dimensional accuracy of the spiral helix blades in these motors. The dimensional accuracy of the width of the groove should be better than 0.02 mm. If you want to roll such a groove in a metal strip, several Waiz stitches are required. The groove is milled into the metal strip using conventional technology, but the surface finish is not high. Milling grooves that extend across the metal band is difficult. Attempts have also been made to roll a longitudinal groove into a metal strip in several rolling passes. In this case, side webs which limit the groove remain on both sides of the groove. Since the metal strip in the area of the groove is correspondingly elongated due to the material displacement during rolling, but not in the area of the side bars, the side bars must be stretched to compensate, for example with reels, which develop a strong tensile force. Even if one stretches the side bars, it is not possible to roll grooves whose depth exceeds approx. 10% of the thickness of the metal strip. In addition, the method is complex and does not lead to the desired accuracy, because the metal strip undergoes a warp with each roll pass, which leads to the fact that the groove becomes somewhat wider from roll pass to roll pass with increasing fluctuations. The working methods described in DE-PS 104 875 and DE 197 04 300 A1 also do not allow high dimensional accuracy.

Through step-by-step and section-wise rolling according to the invention, however, it is possible to roll generally profiled metal strips, in which the profile extends over the entire width of the metal strip, both with high dimensional accuracy and with a high surface quality, especially when the metal strip is not in the multi-step rolling method according to the invention only rolled in one direction and retrieved in the opposite direction, but rolled in both directions, i.e. also when retrieving.

The invention is particularly suitable for discontinuously rolling a regularly recurring profile into a metal strip; From such a metal strip, the same mass parts, such as, for example, spiral helix lamellae or contact springs for electrical purposes, can be obtained with high accuracy by dividing the strip. The tape is advantageously divided by Punching. The method according to the invention can also advantageously be applied to coated strips; their coating is not removed by rolling, in contrast to the production of grooved strips by milling.

The accuracy and surface quality that can be achieved according to the invention are greater than when milling, greater than when the metal strip is repeatedly rolled over its full length, as in the prior art, to produce a longitudinal groove, which is due to the uneven elongation that occurs is only possible up to a maximum thickness reduction of 10%.

The discontinuous mode of operation of the method according to the invention makes a significant contribution to the dimensional accuracy of the profile of profiled metal strips. Because of the discontinuous mode of operation, each rolling step starts from the standstill of the metal strip and the rollers of the rolling stand. For this reason, in the initial phase of each rolling step, the elongation of the metal strip resulting from the engagement of the rollers in the metal strip does not occur abruptly, but in such a way that it is so gentle that a constant tensile stress in the metal strip, which is important for the dimensional accuracy of the profile can be maintained, e.g. by regulating the drive of reels, which are provided for maintaining the tension. For this purpose, the rollers and the metal strip are accelerated and braked to the same extent and synchronously during rolling.

If a profile is to be rolled section by section into a metal strip, one roller can have a cylindrical jacket and the other roller can have a profiled jacket.

It is possible to roll a profile into the strip from above and below. In this case, both rollers are profiled. The shorter the rolling steps, the better the dimensional accuracy and surface quality. The rolling steps are advantageously chosen to be shorter than half the circumference of the rolls. In this case the profile extends only over part of the circumference of the roller. The remaining part of the outer surface of the roller can be cylindrical; this makes it possible, with the cylindrical section of the roll surface, not to profile the respective section of the metal strip in a first rolling step, but to equalize it, thereby increasing the dimensional accuracy of the rolled strip.

One application, for which the invention has been advantageously implemented in order to produce a strip-shaped primary material made of metal, which is profiled in regularly recurring sections, relates to nibs for fountain pens.

Nibs for fountain pens have a different thickness over their length. Nibs are typically 0.2 mm thick in the rear area. The nib becomes thicker towards the tip in order to finally reach a maximum of about 0.6 mm at the nib. It is known to produce nibs in that a metal strip is first provided with a corresponding longitudinal profile by rolling in sections, namely in steps whose length corresponds to the length of the later nibs, which extends over the entire width of the metal strip. This profiled metal band is a raw material from which the nibs are later punched out and shaped into the desired curved shape.

In order to produce the profiled primary material, it is known to provide the upper roller in the circumferential direction with an empirically determined contour of two rollers that delimit a nip and are supported in a roll stand, which contour is complementary to the intended course of the thickness of the nibs. Outside of this coordinated contour, the lateral surface of the upper roller is so close to its axis that there is no engagement with the metal strip in the roll gap in this area. With the beginning of the circumferential section having the coordinated contour, the pierces Roll into the metal strip and then take it with it for the duration of a rolling step, namely as long as it is in engagement with the metal strip, thereby causing both a feed and a profiling of the metal strip. The metal strip is unwound from a first reel and the profiled metal strip emerging from the roll gap is rolled up from a second reel. Since the feed of the metal strip is effected by the two rollers, there is inevitably a certain loose length of the metal strip between them and the second winding reel, which makes it necessary to provide a strip loop with a strip tensioning device which compensates for the discontinuous strip feed the rollers and the continuous winding movement of the second reel. This is associated with some equipment, which is disadvantageous.

Since the upper roller punctures the metal strip to be rolled about 3 mm in front of the plane which passes through the longitudinal axes of the two rollers, it is also known to pretend the metal strip each time before inserting the upper roller using pliers synchronized with the roller rotation the plunging of the upper roller by 1 to 2 mm to keep the waste as small as possible when punching out the nibs later.

Nibs produced in the known manner have undesirable fluctuations in thickness. On the one hand, this is due to the fact that the metal strip from which the starting material is made is already subject to fluctuations in thickness, which are increasingly reflected in the starting material profiled by rolling, in particular in the case of large stitch decreases, with the additional factor that large stitch decreases in the case of hard ones Metal straps are difficult to reach. In view of the 60% to 70% reduction in stitch required for the production of nibs, the person skilled in the art is faced with a serious problem here. The thickness fluctuations that are already in the starting material are typically + 0.02 mm. Further thickness fluctuations are caused by the fact that in the known manner of producing the The material runs continuously around the rollers at a constant speed, causing the piercing of the profiled roller and thus the belt feed to begin suddenly and also to be stopped again. A uniform tensile force in the metal strip during profiling, which would be favorable for a uniform work result with high dimensional accuracy, is not possible with the known method of working.

The present invention, on the other hand, shows a way in which a profiled strip-shaped primary material e.g. for nibs with greater accuracy, namely with fewer deviations of the actual course of the thickness from the target course of the thickness can be produced.

This is made possible by a method further developing the invention with the features specified in claim 12 and by a device with the features specified in claim 44.

According to the invention, the metal strip is rolled in two or more than two rolling steps until the depth of the desired profile of the primary material is reached, so that the overall deformation is achieved not only by a single, but by two or more passes. For this purpose, the metal strip is not allowed to pass through several rolling stands arranged one behind the other; that would be far too expensive and would not or only with difficulty allow the accuracy of the longitudinal positioning of the metal strip in the roll gap, which is required to carry out several roll cuts in one and the same section of the metal strip. Rather, the metal strip is retrieved between two successive rolling steps and then the retrieved section of the metal strip is rolled again between the same two rollers. Only when the desired profile has been rolled into a section of the metal strip to be profiled in two or more than two rolling steps and after one or more return steps, is this next strip section conveyed into the roll gap in order to profile the next strip section of the metal strip. However, it would also be possible, after a first rolling step in a first strip section, if necessary after restoring the initial position of the rolls, for example by turning the rolls back, to carry out the same first rolling step in a subsequent strip section, then to bring the strip back by two steps, and then the second in the first strip section Rolling step and then perform the second rolling step in the second strip section.

The further development of the invention dealing with the production of profiled primary material has significant advantages:

^♦ Because the profile of the metal strip is not produced in one, but in two or more than two rolling steps, greater dimensional accuracy is achieved than before, which is particularly important for nibs in the later area of the barrel.

♦ Since the desired profile in a section of the metal strip is not created by a single, but by two or more than two rolling steps, harder metal strips can also be profiled, including spring-hard ones

Tapes.

♦ This opens up applications for the invention which go beyond the pen area and cover a large number of profiled parts which can be formed from a strip-shaped semi-finished product and separated by punching the strip. Application examples are electrical conductor structures such as Contact springs, power spiral blades for electric motors, lead frames and chain links for watch straps and for jewelry chains.

♦ The possibility of profiling in several rolling steps means that very varied profiles can be created. It is even possible to roll the profile into the metal strip not only from one side, preferably from above, but also from both sides. For this purpose, both rolls, which limit the roll gap, can be provided with a corresponding contour that is not cylindrical in sections and / or one of the rolls be shifted to change the height of the roll gap during rolling.

^♦ The versatility of the invention contributes to the fact that the metal strip does not have to be profiled in every rolling step, but can only be reduced in thickness in a first rolling step, which is why the two rolls also have a cylindrical section, if not anyway are cylindrical. If the metal strip is only profiled from one side, the other roller always has a completely cylindrical surface. ♦ The progress that the invention brings is achieved with minimal equipment. Proceeding from a rolling stand known per se, essentially only the mode of operation that leads to the profiling has to be modified. If one of the two rollers is profiled in the circumferential direction, as is known per se in the manufacture of nibs, then it is designed for purposes of the invention so that it has successively circumferentially sections with different contours, which are separated from one another in particular by cutouts and in connection allow repeated rolling of one and the same section of the metal strip with the intended retrieval of the metal strip. If profiling of the metal strip on both sides is desired, the opposite roller can also be profiled, so that it likewise has sections with different contours in succession in the circumferential direction.

♦ However, it is also possible to design both rolls to be cylindrical and to achieve the change in the height of the roll gap required for profiling during rolling by moving one of the two rolls, preferably the upper one, in the roll stand. This can be done, for example, with an electric motor that drives two spindles, which act on the roller to be displaced and are coupled with an incremental rotary encoder that enables repeatable adjustment, with the aid of which the electric motor is controlled. It is also possible to move the upper roller hydraulically by using two short hydraulic cylinders - the stroke is 50 mm, for example a crossbeam of the roll stand and acts with the crossbeam on the roller to be moved. The piston rods of the two hydraulic cylinders are connected to incremental position transducers, which in turn are part of a control loop that regulates the position of the piston rods to a specified value or to a specified curve profile - depending on the profile to be rolled. Compared to the use of an electronic servo drive, a hydraulic servo drive has the advantage of being faster and more precise. With such a servo drive for moving one roller (the other roller serves as an abutment), it is possible to roll a profile into the metal strip in one or more steps even with cylindrical rollers. It depends on the desired profiling how the roller is to be moved depending on the belt feed. A corresponding control curve, derived from the profile to be rolled, for the drive which is intended to displace the roller can be stored as a control curve in a programmable electronic control unit. By storing a plurality of control curves, according to the invention, a corresponding number of different profiling tasks can be accomplished in metal strips with a roll stand without replacing rolls. If only one roller is moved during rolling, this is preferably the upper roller. Preferably, the upper or the lower roller can be shifted during the rolling in order to be able to roll a profile into the metal strip both from above and from below. Then the other roller serves as an abutment and maintains its position. It is also possible to apply the displacement of a roller during rolling to a roll stand that has a profiled roller. Such a combination of two different options for changing the height of the roll gap during the course of rolling, namely by using a profiled roll in combination with the displacement of a roll, can further increase the versatility of the roll stand for the production of sectionally profiled strips. If two cylindrical rollers are used, it is advantageous to provide one of the rollers, in particular the upper roller, with an axially parallel cut in order to obtain a reference for the rotational angle position of the roller. ♦ The retrieval device, for example the first reel, from which the metal strip to be profiled is unwound, is of particular importance for the retrieval of the metal strip because it must be able to reproduce the length of the step by which the metal strip is retrieved with sufficient accuracy. For this purpose, this first reel is preferably provided with a servo motor which has an incremental rotary encoder which has an accurate

Determination of the desired step length when unwinding and also when winding up.

The width of the metal strip can be dimensioned such that a single profiled part, e.g. a single profiled nib can be punched out. The economy of the method and a rolling stand operating according to the method can easily be multiplied if wider strips are processed which are so wide that two or more than two adjacent nibs or similar profiled objects are formed from each profiled section of the primary material can.

A particularly advantageous development of the invention is the subject of claim 21.

According to this development of the invention, the metal strip is leveled before the profile is rolled. Leveling is understood to mean rolling the metal strip in a roll stand with a highly constant roll gap, as a result of which the thickness fluctuations of the metal strip are reduced. Roll stands for leveling are known from DE 25 41 402 C2, to which reference is made for further details. In a known leveling roll stand, a A highly constant roll gap is achieved by exerting prestressing forces on the roll pins, which are extended outward beyond the roll pin bearings and perpendicular to the roll axes, which can be oriented perpendicularly and preferably in a direction that deviates from the roll axis plane and passes through the incoming metal strip Line of action. In this way, the work cycle of the rolls in the roll neck bearings is reduced.

According to the invention, however, there is no provision for the roll stand provided for profiling the metal strip to be preceded by a further roll stand serving for leveling. Rather, the leveling and profiling are carried out in one and the same roll stand, for which purpose the metal strip is not only moved in the feed direction through the roll gap in the working steps serving for profiling. Rather, the metal strip is first leveled in steps that are at least as long as the step in profiling, with a moderate decrease in its thickness. The strip is then retrieved by one step of at least the length required for profiling and at most the length advanced during leveling, and then the profile is rolled into the section of the metal strip that has been retrieved. In a roll stand in which the first roll is cylindrical and the second roll is profiled and has a peripheral section with the contour which is matched to the desired course of the thickness, for example a pen, which is to be produced from the metal strip, has the second For this purpose, additionally roll a cylindrical peripheral portion, which is separated from the peripheral portion having the contour (claim 26). The leveling step is carried out with the cylindrical peripheral section. The cylindrical peripheral section is chosen so long with regard to its determination and taking into account the elongation of the metal strip that occurs during rolling that the equalized section of the metal strip has at least the length of the nib, preferably a little longer, so that the beginning and / or the end of the profiling step can keep a distance from the beginning and end of the equalized section. According to the invention, the roll stand which serves for profiling is thus simultaneously designed as a roll stand for leveling and is equipped with a step-by-step forward and backward band feed.

The development of the invention according to claim 21 and claim 26 has significant advantages:

♦ The thickness fluctuations of + 20 μm in the primary material and thus also in the later nibs can be reduced to less than + 2 μm in a single nib, especially in the later shaft area of the nibs. With a supplied device, nibs with fluctuations in thickness of + 1 μm could be produced.

♦ The reproducibility of the thickness from pen to pen has initially reached + 4 μm. With the device delivered, a reproducibility of + 2 μm was even achieved.

♦ These are accuracies that have so far not been achieved in the production of nibs by rollers. Corresponding accuracies can also be achieved with strip-shaped primary material for profiled products other than nibs.

^♦ The great advance in accuracy is achieved with minimal equipment. Starting from a rolling stand known per se, the work roll used for profiling is to be modified in this, in that it is provided with a suitable cylindrical section, and the roll journals of the two rolls are to be preloaded in order to reduce the bearing play, for example to one of those in the DE-25 41 402 C2 disclosed ways. According to DE 2541 402 C2, the roll journals of the two rolls are not preloaded directly, but indirectly by prestressing the roll journals

Back-up rolls that preload the two rolls (also known as work rolls). However, it is also possible to pretension the two (work) rolls immediately. You also need funds that are not just one step by step, but also allow a gradual return of the metal strip in steps that are approximately as long as the steps in leveling. As already mentioned, this can be done simply by providing at least the first reel, from which the metal strip to be profiled is unwound, with an electric motor, which steers with sufficient accuracy in steps of the desired length and reverses in the direction of rotation leaves. This is preferably done with a servo motor, which has an incremental rotary encoder, which enables precise definition of the desired step length during unwinding and winding up. A servo motor is usually with a subordinate one

Gearbox connected. When servomotors are discussed below, it is assumed that they are normally also connected to a downstream transmission.

The second reel, which winds up the profiled metal strip, is preferably also provided with such a servo motor.

^♦ This has the further advantage that through the interaction of the servo motors in all phases, not only when leveling, but also when profiling and when retrieving the metal strip, a defined tension can be exerted on it, which also helps to achieve a uniform primary material Favored thickness fluctuations. This tension should be as constant as possible and not fall below a certain basic tensile force, which can be 500 N, for example, when producing nibs. When retrieving, the first reel therefore pulls the metal strip with greater force against the smaller reel force of the second reel. By maintaining a constant basic tensile force in the metal strip in all phases of the

Processing the metal strip results in improved uniformity of the rolled starting material and prevents the occurrence of a strip run, ie the metal strip does not warp. ^♦ Another advantage of driving the reels with servomotors is that the belt feed and the drive of the two rollers can be coordinated so well that, unlike in the prior art, a discontinuous roller drive can take place instead of a continuous drive of the rollers. In particular, the speed at which the profiled roller punctures the metal strip can be matched to the strip feed speed in such a way that there is no abrupt acceleration of the metal strip when piercing. In particular, the profiled roller can first be inserted into the metal strip with slow strip feed and with slow roller rotation, followed by an accelerated strip feed movement and roller rotation. This is particularly advantageous for achieving small thickness tolerances.

♦ Another advantage of using servomotors to drive the reels is that special belt tensioning devices, as are required in the prior art, are not required.

♦ Another advantage of using the servo motors to drive the reels is that the strip feed can be adjusted very precisely to the length and position of the profiled strip sections and to the rotation of the rolls by a programmable electronic control unit, preferably also to the vertical displacement of one Roller, in particular to change the height of a roller gap delimited by two cylindrical roller shells or roller shell sections and thereby to produce a specific profile.

The metal strip can be retrieved not only by a reel arranged on the inlet side of the roll gap, but also by a return device designed as a plier feed device. This embodiment of the invention is particularly suitable for processing shorter or stiffer strips, in particular for producing a pre-material for proofs. If the return device is a tongs feed device, it can be moved over it can also be used to advance the metal strip and feed it to the roll gap.

Instead of a reel arranged on the outlet side of the roll gap, a tong feed device can also be used as a pulling device for the strip emerging from the roll gap during rolling. This embodiment is also particularly suitable for processing shorter or stiffer tapes.

The quality of the strip-shaped primary material produced is increased if a defined tension is maintained in both the rolling and the retrieval of the strip, the thinner the metal strip being, the more favorable this influence is. But also with thicker tapes, e.g. used for the production of proofs, it is advantageous to keep the tape under tension and to guide it precisely during the rolling and retrieval between the retrieval device and the pulling device by a coordinated movement of these two devices.

In the method according to the invention, the optimum strip tension can be maintained in all phases of a rolling step, in particular also in the critical phase of inserting a profiled roller into the metal strip, because because of the nature of the discontinuous multi-step rolling method from the standstill of the Rolls and the metal strip starts out, the engagement of the profiled roller in the metal strip does not occur suddenly, but so smoothly that in this critical phase of the insertion of the profiled roller into the metal strip and in the entire rolling step, the tensile force of the strip tensioning device, for example the reels, can be regulated to an optimal constant value for the respective band. For this purpose, the reels and the rollers are advantageously synchronized and accelerated or braked to the same extent with their respective drive motors when the metal strip and the rollers are accelerating and braking. The optimal preload, with which the bearing play of the rollers is clamped away, can be determined empirically for the respective application and then remains constant for the application. The optimization is preferably carried out in such a way that the elongation of the roll stand occurring in the respective application when leveling is compensated for and compensated for by appropriate adjustment of the prestress.

The leveling of the metal strip can not only take place when a profiled material is being produced, but also when producing a non-profiled material, as is e.g. is used for proofs. In this case, the two rolls are cylindrical anyway and can be used for leveling in any position if the roll stand has a leveling design which reduces the influence of the play of the roll neck in their positions.

Further features and advantages of the invention result from the attached schematic drawings, which show exemplary embodiments of the invention.

FIG. 1 shows a partially sectioned side view of a machine according to the invention,

FIG. 2 shows a partially sectioned front view of the machine,

FIG. 3 shows an enlarged section of the machine compared to FIG. 1, namely the main part of the roll stand of the machine,

FIG. 4 shows an enlarged detail from FIG

Machine, namely the rolling stand, the

FIGS. 5-10 show a flow diagram of a first working method that can be carried out with the machine FIGS. 11-16 show a flow diagram of a second working method that can be carried out with the machine

Figure 17 shows a schematic diagram for carrying out the invention with two cylindrical rollers

FIG. 18 shows two rollers divided into six circumferential sections to explain a method for producing a pre-material for proofs, and the

Figure 19 shows a modified machine according to the invention in a representation corresponding to Figure 1.

Corresponding parts are identified in the examples with matching reference numbers.

The machine shown in Figure 1 and Figure 2 has a foundation 1, on which a roll stand 2 is built in the middle, in front of and behind which a receiving device 3 and 4 for a reel 5 and 6 is fastened, which by an electrical Servomotor designed drive motor 7, 8 can be driven.

Two work rolls 11 and 12, hereinafter simply referred to as rolls, are mounted in lateral installation parts 9 and 9a of the roll stand, which together delimit a roll gap 13. Above the upper roller 12 and below the lower roller 11, a support roller 14 and 15, respectively, of larger diameter is installed in built-in parts 10 and 10a. The built-in parts 9, 9a of the work rolls 11 and 12 are each arranged in a section of the built-in parts 10, 10a of the support rolls 14, 15. In the lower installation part 9 there are two short hydraulic cylinders 46, 47, which on the upper installation part 9a act and serve to compensate for a bending of the work rolls 11, 12 occurring during rolling.

A metal strip 16 to be processed runs from the reel 5 via an overflow roller 17 into the roll gap 13, passes through it and passes via a further overflow roller 18 to the second reel 6, which winds up the metal strip 16 processed in the roll stand 2. Between the roll gap 13 and the second overflow roller 18 there is also a device 19 for extracting rolling oil, in which the metal strip 16 is cleaned of the rolling oil.

The structure of the roll stand 2 is shown in more detail in FIGS. 3 and 4. It follows from this that the two rollers 11 and 12, the diameter of which is only approximately 1/3 of the diameter of the support rollers 14 and 15, are mounted with their roller journals 20 and 21 in roller journal bearings 22, which are designed as roller bearings. A roll neck 21 of each of the two rolls 11 and 12 is extended beyond its roll neck bearing 22 and is designed as part of a cardanic suspension 23, which enables the drive of the two rolls 11 and 12 in each case by means of a cardan shaft 24. An electric motor 41 driving the two rollers 11 and 12 synchronously via the cardan shafts 24 is shown in FIG. It drives the rollers 11 and 12 via a branching gear 48. However, it is also possible to drive the rollers 11 and 12 by two separate motors, as will be discussed with reference to FIG. 17.

The support rollers 14 and 15 have roller journals 25 which are mounted in roller journal bearings 26 of the lateral built-in parts 10 and 10a which are designed as roller bearings. The roller journals 25 are extended beyond the roller journal bearings 26 and are inserted in bearing shells 27, of which the bearing shells of the lower support roller 14 are braced with the foundation 1, while the bearing shells 27 of the upper support roller 15 are braced with a crossbar 28 arranged above them. The bracing is done with one of the bearing shells 27 outgoing threaded rod 29, on which a set of plate springs 30 is arranged, which is tensioned by a nut 31. This is only shown above the crossbeam 28, but is provided on the foundation 1 in the same way. This preload reduces the bearing play of the support rollers 14 and 15 and thus its influence on the deviations in the thickness of the rolled metal strip from its target thickness. The rollers 11 and 12 as well as the support rollers 14 and 15 thus achieve a concentricity of + 1 μm.

The required pre-tension of the roll stand 2 is generated with the aid of two spindles 32 and 33, which press from above onto the cross member 28 and onto the bearing shells 27 and each by its own electric motor 34 arranged on the top of the roll stand 2 (see Figure 1) are driven. For this purpose, both electric motors 34 have a drive shaft 49 designed as a pinion, the teeth of which each mesh with a gear wheel 50. The two gear wheels 50 are fixed in a rotationally fixed manner on one spindle 32 and on the other spindle 33. The suitable preload of the roll stand is determined empirically from the elongation of the roll stand in the respective application and set so that the elongation is compensated for. After this presetting, the machine according to the invention operates as follows:

The metal strip 16 to be processed is unwound from the first reel 5, passed through the roll gap 13, pulled up to the second reel 6 and fastened thereon.

The first, lower roller 11 has a cylindrical outer surface 11. The second, upper roller 12 has an outer surface (FIG. 5) with a profiled peripheral section 35, which has a length L1 in the circumferential direction of the roller 12, and a cylindrical peripheral section 36, which measured in the circumferential direction of the roller 12 has a length L2, both separated from one another by two cutouts 37 and 38. The cylindrical peripheral portion 36 of the lateral surface has the greatest distance from the axis of the second roller 12, the Notches 37 and 38 have the smallest distance from the axis of the second roller 12. The profiled peripheral section 35 of the lateral surface has a contour, the course of which is coordinated in the circumferential direction with the longitudinal course of the thickness of the nib, which are finally produced from the metal strip 16 should.

The first, lower roller 11, which is cylindrical, is only partially shown in FIGS. 5 to 16.

The processing of the metal strip 16 begins with the cylindrical circumferential section 36 of the second roller 12 piercing into the metal strip stretched between the two reels 5 and 6, and in fact gently at a slow feed speed of the metal strip 16 which is adapted to the circumferential speed of the cylindrical circumferential section 36 This puncturing phase is shown in FIG. 5, but not to scale, but with an excessively thick metal strip 16. In the further course of FIGS. 6 to 16, the stitch decreases of the metal strip are also shown exaggerated by the rolling process in order to make the rolling process clearer. The cylindrical peripheral section 36 rolls on the metal strip 16 and typically reduces its thickness from 0.66 mm to 0.60 mm while at the same time equalizing the thickness. The end of the leveling step is shown in FIG. 6. The metal strip 36 now comes out of the engagement of the cylindrical peripheral portion 36 of the second roller 12, which rotates a little further until the cutout 37 faces the metal strip 16. Preferably, when the rollers 11, 12 are shut down, the metal strip 16 is now brought back by reversing the two drive motors 7 and 8 designed as servomotors, namely by a length which is greater than L1 but less than L2; L2 is the length over which this Metal band 16 was leveled. The length by which the metal strip 16 is retrieved is chosen so that in the next step (FIG. 7), when the movement of the rollers 11 and 12 and the feed movement of the metal strip 16 are started again, the profiled peripheral section 35 of the roller 12, which the on the Nibs matched contour immediately after the beginning of the equalized section of the metal strip 16 gently pierces it (FIG. 7) or slightly, for example 2 mm, behind it. While the cutout 37 faces the metal strip 16, the upper, second roller 12 is displaced downward by such a degree by rotating the spindles 32 and 33 that the profiled circumferential portion 35 of the roller 12 which pierces the metal strip 16 next is the desired one Penetration depth is reached. When the second roller 12 rotates further and the metal strip 16 is advanced by means of the second reel 6, the profiled circumferential section 35 is used to roll the profile provided for the nib over the entire width of the metal strip 16 into its equalized section (FIGS. 7 and 8) ). Figure 8 shows the end point of the roll forming step. It ends at a short distance before the end of the equalized section at its level. As the upper roller 12 continues to rotate, its cutout 38 faces the metal strip 16. In this phase, the upper roller 12 is moved upwards again by rotating the spindles 32 and 33, so that the height of the roll gap 13 required for the subsequent leveling rolling step is set. The position of the cutout 38 between the profiled circumferential section 35 and the cylindrical circumferential section 36 of the second roller 12 and the positioning of the metal strip 16 in the roll gap 13 by means of the servomotors 7 and 8 of the reels 5 and 6 are coordinated with one another so that the next puncture of the cylindrical circumferential section 36 takes place at a small, approximately 2 mm distance behind the end of the previously leveled section of the metal strip 16 (FIG. 9), which initiates a further leveling step, as shown in FIGS. 9 and 10.

During leveling, profiling and retrieval, the servomotors 8 and 9 ensure that the tension in the metal strip 16 is as uniform as possible.

The exemplary embodiment shown in FIGS. 11 to 16 differs from the exemplary embodiment shown in FIGS. 5 to 10 in that the upper roller 12 not only has two peripheral sections, but also three Circumferential sections 35, 36 and 40, which are separated from one another by cutouts 37, 38 and 39, act on the metal strip 16 to be machined. The roll stand 2 provided for this purpose has the same structure as that shown in FIGS. 1 to 4, with the proviso that the roller 12 shown in FIGS. 11 to 16 is used as the upper roll 12.

The peripheral section 36 is cylindrical, whereas the two peripheral sections 35 and 40 have a non-cylindrical profile. As in the example in FIGS. 5 to 10, the cylindrical circumferential section 36 is continuously at the greatest distance from the axis of the roller 12, which is advantageous when it comes to regrinding the cylindrical circumferential section, which is used for leveling, as required.

The working method shown in Figures 11 to 16 corresponds to the working method shown in Figures 5 to 10 with the special feature that after leveling the relevant section of the metal strip 16 is not profiled in one, but in two successive rolling steps, between which the metal strip 16 is retrieved again.

FIG. 11 shows, analogously to FIG. 5, the piercing of the cylindrical peripheral section 36 of the roller 12 into the metal strip 16. FIG. 12 shows, analogously to FIG. 6, the end of the leveling rolling step. By turning the upper roller 12 further, the metal strip 16 comes out of its engagement and can be retrieved by the reel 5. During this phase, the upper roller 12 is moved downwards by means of the spindles 32 and 33 in order to adjust the height of the roller gap 13 for the subsequent first roll forming operation, the beginning of which is shown in FIG. 13. Figure 13 corresponds to Figure 7 and shows the piercing of the first non-cylindrical, profiled peripheral portion 35 of the roller 12. Figure 14 corresponds to Figure 8 and shows the end of the first roll forming step. When the roller 12 continues to rotate, the metal strip 16 comes out of its engagement again and in this phase, while the cutout 39 faces the metal strip 16, it is brought back again and by actuating the spindles 32 and 33 the roll gap 13 for the second roll forming step 15, the beginning of which is shown in FIG. 15 when the profiled peripheral section 40 is pierced.

Figure 16 shows the end of the second roll forming step. By turning the roller 12 further, the metal strip 16 becomes free again and can be positioned for leveling in the subsequent strip section, while simultaneously adjusting the height of the roll gap 13 provided for leveling. The sequence of steps shown in FIGS. 11 to 16 is then repeated.

This method of working is particularly suitable for the production of profiled sections in strips in which the desired stitch removal cannot be achieved or can only be achieved with difficulty or with the desired accuracy in a single profiling roll step.

The invention can also be carried out with more than two roll forming steps. In order to accommodate the required number of peripheral sections that participate in the rolling process, the diameter of the roller 12 can be increased as required.

It is also possible to provide, in addition to or instead of a leveling rolling step, a reducing rolling step in which the thickness of the metal strip 16 is initially reduced uniformly in sections before it is profiled in a later rolling step.

It is also possible to profile the metal strip 16 on both sides as required. In this case, a roller is used as the lower roller 11 instead of a cylindrical roller, which roller except one or more cylindrical Circumferential sections in a manner similar to that of the upper roller has one or more profiled circumferential sections which are separated from one another by cutouts. If, as preferred, the two rollers 11 and 12 can be driven separately, they can be used for a wide range of profiling tasks. Thus, when the rollers 11 and 12 are driven separately, it can always be ensured that a cylindrical peripheral portion of the one roller cooperates with any other peripheral portion of the opposite roller during the rolling process, regardless of how the sequence of the peripheral portions is selected on the respective roller.

The invention is applicable not only to the production of primary material for nibs, but also for the production of other ribbon-shaped primary materials which are profiled in a series of regularly recurring sections over the entire width of the metal ribbon 16, e.g. for the production of a band-shaped primary material for the production of electrical conductor structures such. B. contact springs or lead frames or for the production of grooved strips with transverse to the longitudinal direction of the metal strip 16 grooves which extend continuously from one to the other longitudinal edge of the metal strip and from which e.g. Commutator bars, electrical connectors or other electrical contact parts can be punched out. Any profile shape that can be produced using optionally profiled rollers can be formed by the method according to the invention.

FIG. 17 shows in a schematic diagram how the servomotors 7 and 8 of the two reels 5 and 6, preferably also electric motors 41 and 42, also designed as servomotors, for driving the two rollers 11 and 12, and the two electric motors 34, in which it these are preferably also servomotors with a downstream gear 34a and with which the upper roller 12 can be displaced by means of the spindles 33 and 32 and are linked to one another via a uniform electronic control device 43. In this way, depending on a predetermined and the control unit 43 Profile shape, preferably stored in digital form, which is to be rolled into the metal strip 16, is controlled by controlling the servomotors 7 and 8, the feed of the metal strip 16 during rolling and during retrieval, and the rollers 11 and 12 are rotated, stopped and, if necessary, turned back and depending on the feed of the metal strip 16 and the profile shape entered into the control device 43, the roller 12 is displaced by actuating the electric motors 34. The current positions are reported back to the control unit 43 by incremental rotary encoders. These rotary encoders are part of the servomotors 7, 8, 41 and 42. Between the spindles 32 and 33 and the two servomotors 34, an incremental rotary encoder 44 is shown separately as an example.

FIG. 17 shows two cylindrical rollers 11 and 12, of which the upper roller 12 has a radial, axially parallel cut 45 in order to obtain a reference for the angular position of this roller 12. In the event that the upper roller 12 has a non-cylindrical peripheral portion, as shown in the previous examples, a displacement of the upper roller 12 during the rolling can be omitted; if necessary, it would then only take place between the individual rolling steps.

The curve according to which the displaceable roller 12 is displaced can not only be stored in the control unit by software. In principle, mechanical cam control is also possible with the aid of a cam disc running synchronously with the belt feed.

The roll stand shown in FIG. 17 can also be used to produce a starting material for proofs with a particularly high surface quality. In this case, the upper roller 12 expediently does not have the radial, axially parallel cut or not over its full length, but only at one of its edges, which is sufficient to obtain an absolute reference for the angular position of this roller 12. For example, assume that the circumference of the rollers 11 and 12 is so matched to the diameter of the proofs to be produced that six proofs can be punched out in succession from a length of the starting material which is the same as the circumference of the rollers 11 and 12. Therefore, the roll surface is divided into six equal peripheral sections I to VI. The method according to the invention can thus be carried out, for example, as follows: At the beginning, the outer surface of the two rollers 11 and 12 is lapped to a mirror finish. It is assumed that each section of the metal strip 16 having a length which corresponds to approximately 1/6 of the circumference of the rolls 11 and 12 is finished in three rolling steps. For this purpose, a first strip section is rolled between the peripheral sections I, the roll gap 13 is opened, the metal strip 16 is retrieved around the rolled section, rolled again between the peripheral sections I, retrieved a second time and then finished rolled between the peripheral sections II.

The second section of the metal strip 16 is rolled in the first rolling step between the peripheral sections I, retrieved, rolled in the second rolling step between the peripheral sections II, retrieved and finished rolled in the third rolling step between the peripheral sections III.

The third section of the metal strip 16 is rolled between the peripheral sections II in the first rolling step, then retrieved, rolled, retrieved between the peripheral sections IM in the second rolling step and rolled between the peripheral sections IV in the third rolling step.

The fourth section of the metal strip 16 is rolled between the peripheral sections III in the first rolling step, then retrieved, rolled between the peripheral sections IV in the second rolling step, retrieved and rolled between the peripheral sections V in the last rolling step.

The fifth section of the metal strip 16 is rolled between the peripheral sections IV in the first rolling step, retrieved, then in the second rolling step rolled between the peripheral sections V, retrieved and rolled between the peripheral sections VI in the last rolling step.

This cycle can be repeated as long as the surface quality that can be achieved with it meets the requirements. The number of cycles required to obtain the desired surface quality can be determined by preliminary tests. However, it is also possible to provide a thickness measuring device between the roll gap 13 on one side and the second reel 6 on the other side, which measures the thickness of the metal strip 16 emerging from the roll gap 13. Such a thickness measuring device 51 is shown schematically in FIG. 17 and shown more specifically in FIG. 19. The structure of the thickness gauge 51 is state of the art. It can be a measuring device with a mechanical probe head with a diamond tip, the deflection of which is picked up electrically, or a device which measures the strip thickness without contact with the aid of X-rays by measuring the weakening of the strip as it passes through the strip. Such a thickness measuring device 51, as shown in FIG. 17, can be part of a control circuit in which it determines the actual value of the strip thickness, inputs it to the electronic control device 43 as an input value, which compares the actual value with a predetermined target value and from it an actuating signal for the two Forms electric motors 34, which bring about a corresponding adjustment of the roll gap 13.

The device shown in FIG. 17 can also be used to produce metal strips or metal strips with a profile which extends transversely to their longitudinal direction and has a profile which extends continuously over the entire width of the metal strip 16 if one of the two rollers 11, 12 has a profile which extends in the circumferential direction appropriate profiling is provided.

FIG. 19 shows an exemplary embodiment modified compared to FIGS. 1 to 4. It differs from the exemplary embodiment in FIGS. 1 to 4 in that, instead of reels 5 and 6, tongs feed devices 52 and 53 are provided. This embodiment is particularly suitable for shorter or thicker metal strips 16, which cannot be wound so easily. This embodiment is particularly suitable for producing a starting material for proofs in lengths of, for example, a few meters.

The tongs feed devices 52 and 53 have a slide 56, 57, which can be approached and removed from the roll gap 13 in the horizontal direction by means of a servo motor 54, 55. For this purpose, a dovetail-shaped tongue 58 is provided on the underside of the slide 56, 57, which engages in a matching dovetail-shaped groove 59, 60, which is formed on an attachment part 61, 62 of the roll stand 2. Through the engagement of groove 59, 60 and tongue 58, the carriages 56, 57 are precisely guided horizontally. Other types of guidance are possible. On each slide 56, 57 there is a lower jaw 63 rigidly attached to the slide and an upper jaw 64 whose distance from the lower jaw can be changed, preferably by means of a pressure center cylinder. The metal strip 16 is passed between the two jaws 63 and 64, which form a pair of pliers or clamps, and clamped as required. The tongs feed devices 52 and 53 can be actuated and moved individually but also together in a coordinated manner. In the second case, it is possible to maintain a defined tensile stress in the section of the metal strip 16 clamped between the two tongs feed devices 52 and 53, both during rolling and when retrieving.

As shown in FIG. 19, the two tong feed devices 52 and 53 are arranged adjacent to the roll gap 13. On the outlet side of the roll gap 13, in the rolling direction following the tong feed device 53, the device 19 for suctioning rolling oil is arranged, to which a thickness measuring device 51 connects, which detects and reports the thickness of the rolled metal strip 16 with a probe or without contact. so that at Deviations from the desired thickness can be controlled or regulated to change the height of the roll gap 13 in a suitable manner.

List of reference numbers:

1. Foundation

2. Roll stand 3. Pick-up device

4. Recording device

5th reel

6. reel

7. Drive motor (servo motor) 8. Drive motor (servo motor)

9 Installation part for work rolls 9a Installation part for work rolls 10. Installation part for support rolls 10a Installation part for support rolls 11. 1st roll (work roll)

12. 2nd roller (work roller)

13. Roll gap

14. Back-up roller

15. Back-up roller 16. Metal band

17. Overflow roller

18. Overflow roller

19. Device for suction of rolling oil

20. Roll neck 21. Roll neck

22. Rolling pin bearing (roller bearing)

23rd gimbal

24. Propshaft

25. Roll neck 26. Roll neck bearing (roller bearing)

27. Bearing shell

28th traverse

29. Threaded rod

30. Disc springs 31. Mother

32. spindle

33rd spindle

34. Electric motor

34a downstream gear 35th profiled peripheral portion

36. cylindrical peripheral portion

37. Exemption

38. Exemption

39. clearance 40. profiled circumferential section 41. electric motors 42. Electric motors

43. electronic control unit

44. Encoder

45th incision

46. Hydraulic cylinder

47. Hydraulic cylinder

48. Transmission

49th wave

50th gear

51. Thickness gauge

52. Plier feed device

53. Plier feed device

54. Motor for 52

55. Motor for 53

56. Sledge

57. Sledge

58th pen

59. groove

60. groove

61. Neck part

62. neck part

63. lower jaw

64. upper jaw

Claims

Expectations:

1. A method for producing a strip-shaped primary material made of metal by means of rollers (11, 12) of a roll stand (2) which limit a roll gap (13) by the metal strip being rolled in two or more than two rolling steps, characterized in that the metal strip (16) is successively rolled in successive sections between the same two rollers (11, 12), for which purpose the metal strip (16) is retrieved after rolling such a section of the metal strip (16) and the retrieved section is rolled again, the retrieved section of the metal strip (16) is chosen to be shorter than the circumference of the rollers (11, 12).

2. The method according to claim 1, characterized in that the metal strip (16) is rolled even when retrieving.

3. The method according to claim 1 or 2, characterized in that the retrieved sections of the metal strip (16) are selected at most half as long as the circumference of the rollers (11, 12).

4. The method according to claim 1, 2 or 3, characterized in that both rollers (11, 12) are selected cylindrically.

5. The method according to any one of the preceding claims, characterized in that the last rolling step takes place in each of the retrieved sections of the metal strip (16) between those peripheral sections of the two rolls (11, 12), which in the preceding one or more Rolling steps have not yet acted on the relevant section of the metal strip (16).

6. The method according to claim 5, characterized in that the stepwise repeated rolling of the relevant section of the metal strip (16) is carried out in such a way that of the peripheral sections of the two rolls (11,

12) which act on the relevant section of the metal strip (16), the circumferential section of the two rolls (11, 12) acting on the relevant section of the metal strip (16) in the first rolling step has the greatest number and that on the relevant section in the last rolling step of the metal strip (16) acting circumferential section of the rollers (11, 12) have carried out the smallest number of rolling steps.

7. The method according to claim 6, characterized in that zero is selected as the smallest number.

8. The method according to claim 5, 6 or 7, characterized in that the outer surface of the two rollers (11, 12) is reworked to restore the original surface quality if their peripheral sections, with which the least number of rolling steps were carried out, a predetermined number of rolling steps.

9. The method according to claim 8, characterized in that the predetermined number of rolling steps is matched to the desired surface quality of the strip-shaped primary material.

10. The method according to any one of the preceding claims, characterized in that the metal strip (16) is equalized by the rolling at the same time.

11. The method according to any one of the preceding claims, characterized in that proofs for coins and medals are made from the primary material.

12. The method according to any one of the preceding claims, characterized in that a profile is rolled in sections in the metal strip (16) which extends over the entire width of the metal strip (16) and one over the length of the metal strip (16) changing thickness of the metal strip (16).

13. The method according to claim 12, characterized in that a periodically repeating profile is rolled into the metal strip 16.

14. The method according to any one of the preceding claims, characterized in that the rollers (11, 12) and the metal strip (16) are accelerated and braked synchronously and to the same extent in the respective rolling steps.

15. The method according to any one of claims 1 to 3, 10 and 12 to 14, character- ized in that a rolling stand (2) is used in which to produce a strip-shaped material with a profile, which recurs in successive sections of the material the height of the roll gap (13) is variable, and that the metal strip (16) with its sections to be profiled is repeatedly passed through the roll gap (13) in steps of predetermined lengths (21) until in the relevant sections of the metal strip (16) the depth of the desired profile of the primary material has been reached.

16. The method according to any one of claims 12 to 15, characterized in that in two or more than two rolling steps, a profile is rolled into the retrieved section of the metal strip (16).

17. The method according to any one of claims 12 to 16, characterized in that the profile is rolled from above into the metal strip (16).

18. The method according to any one of claims 12 to 16, characterized in that the profile is rolled from below into the metal strip (16).

19. The method according to any one of claims 12 to 16, characterized in that a profile is rolled into the metal strip (16) from above and from below.

20. The method according to any one of claims 12 to 19, characterized in that the metal strip (16) is reduced in its thickness in a first rolling step, but is not yet profiled.

21. The method according to claim 20, characterized in that the metal strip (16) is leveled in the first rolling step.

22. The method according to claim 20 or 21, characterized in that on the

Reduction rolling step one or more profiling rolling steps between the same two rolls (11, 12) follow.

23. The method according to claim 20, 21 or 22, characterized in that the length (L2) of the reducing rolling step is greater than the length (L1) of the next profiling rolling step.

24. The method according to any one of claims 20 to 23, characterized in that the metal strip (16) after the reducing rolling step is retrieved by a length which is less than the length (L2) of the reducing rolling step and greater than the length (L1) of the the next subsequent roll forming step in the same section of the metal strip (16).

25. The method according to any one of claims 12 to 24, characterized by the use of a roll stand (2), in which at least one of the two

Rolls (12) has a profiled section (35, 40) in its lateral surface with a contour which, together with the contour of the other roll (11), delimits the roll gap (13).

26. The method according to claim 25, characterized in that before the rolling of a profile, the metal strip (16) in the roll gap (13) between the same

Rolls (11, 12) are first leveled in steps of a length (L2), which does not fall short of the length (L1) of the first profile rolling step, with a moderate decrease in their thickness, then by a step of at least the length (L1) of the first profile rolling step and at most the second length (L2) is retrieved and then the profile is rolled into the retrieved section of the metal strip (16), and that the rollers (12) for leveling the metal strip (16) have a cylindrical peripheral section (36) on their outer surface, which possibly separated from the profiled peripheral sections (35, 40) which have a non-cylindrical contour.

27. The method according to any one of claims 12 to 26, characterized in that a roller (12) of the roll stand (2) is displaced to change the height of the roll gap (13) during the rolling of the metal strip (16).

28. The method according to claim 27, characterized in that the upper or lower roller (11, 12) is shifted during the rolling of your choice.

29. The method according to claim 27, characterized in that the roller in question (11, 12) is displaced by a servo drive (32, 34, 44).

30. The method according to claim 29, characterized in that one or two electric motors (34) or one or two short hydraulic cylinders are used for the servo drive.

31. The method according to any one of claims 27 to 30, characterized in that the displacement of the roller (12) by means of a program-controlled drive (32, 33, 34, 44) takes place, in a programmable control unit (43) in the respective rolling step generating profile is stored as a control curve for the drive (32, 33, 34, 44) causing the displacement of the roller (12).

32. The method according to any one of claims 27 to 31, characterized in that one of the rollers, in particular the upper roller (12), has an axially parallel cut (45).

33. The method according to any one of the preceding claims, characterized in that the two rollers (11, 12) are driven step by step and synchronously with the feed of the metal strip (16).

34. The method according to any one of the preceding claims, characterized in that the two rollers (11, 12) are rotated differently when the metal strip (16) is retrieved.

35. The method according to any one of claims 15 to 32, characterized in that a clearance (37, 38, 39) is provided in the lateral surface of the rolls (11, 12) between the peripheral sections (35, 36, 40) which are effective during rolling which extends over such a circumferential angle that the respectively following circumferential section (35, 36, 40) that is effective during rolling only engages in the metal strip (16) after the previous circumferential section that is effective during rolling has released the metal strip (16) .

36. The method according to any one of the preceding claims in connection with claim 11 or 25, characterized in that the thickness of the metal strip

(16) is reduced by an order of a tenth of the thickness when leveling.

37. The method according to any one of the preceding claims, characterized in that the metal strip (16) to be rolled is unwound from a first reel (5) and the rolled metal strip (16) is wound onto a second reel (6) and that the speed of rotation the rollers (11, 12) and the peripheral speed of the second reel (16) are matched to one another, in particular in the phase of the insertion of the rollers (12, 13) into the metal strip (16).

38. The method according to any one of the preceding claims, characterized in that the insertion of a roller (12) at a reduced rotational speed of the roller (12) and accordingly at a lower feed speed of the metal strip (16) and that the movements are subsequently accelerated.

39. The method according to any one of claims 1 to 36, characterized in that the metal strip (16) is retrieved with a first pair of pliers (52).

40. The method according to claim 39, characterized in that the metal strip (16) with the first pliers (52) is also advanced for rolling.

41. The method according to claim 39 or 40, characterized in that the metal strip (16) is pulled during rolling with a second pair of pliers (53) which engages the section of the metal strip (16) which leaves the roll gap (13).

42. The method according to any one of the preceding claims, characterized in that during the rolling as well as during the retrieval of the

Metal strip (16) is constantly maintained in this tension.

43. The method according to any one of the preceding claims, characterized in that the metal strip (16) is chosen so wide that two or more than two of the objects lying side by side from the objects which are intended to be punched out of the primary material formed by rolling can be punched out.

44. Use of a device with a roll stand (2) with two rolls (11, 12) which delimit a roll gap (13), the height of which is variable, and with a return device (5, 52) arranged on the inlet side of the roll gap (13) ) for a metal strip (16) to be rolled,

for producing a band-shaped primary material made of metal with a profile, which recurs in successive sections of the primary material, according to the method according to claim 12,

for which the first (11) and / or the second roller (12) has two or more than two circumferential successive, separate circumferential sections (35, 36, 40) on their lateral surface, which do not all match in their contours, and for what purpose on the inlet side of the roll gap (13) provided return device (5, 52) a drive motor (7, 54) is provided, which enables the metal strip (16) to be returned in steps of a predetermined length.

45. The use of a device according to claim 44, in which the return device is a first reel (5).

46. The use of a device according to claim 44, in which the return device is a tong feed device (52).

47. The use of a device according to one of claims 44 to 46, in which a pulling device (6, 53) for the strip-shaped primary material is provided on the outlet side of the roll gap (13).

48. The use of a device according to claim 47, in which the pulling device is a second reel (6) for winding up the strip-shaped primary material.

49. The use of a device according to claim 47, in which the pulling device is a second forceps feed device (53).

50. The use of a device according to one of claims 44 to 49, in which the two rollers (11, 12) can be driven independently of one another.

51. The use of a device according to any one of claims 44 to 50, in which at least one roller (11, 12) has a cylindrical peripheral portion (36).

52. The use of a device according to claim 51, in which both rollers (11, 12) have a cylindrical peripheral portion (36).

53. The use of a device according to one of claims 44 to 52, in which the roll stand (2) is designed as a leveling roll mill.

54. The use of a device according to one of claims 44 to 53, in which the drive motor (7, 52) for the return device (5, 52) provided on the inlet side of the roll gap (13) is an electric servo motor.

55. The use of a device according to any one of claims 44 to 54, in which that provided on the outlet side of the roll gap (13) Pulling device (6, 53) is driven by an electric servo motor (8, 55).

56. The use of a device according to one of claims 44 to 55, in which the two rolls (11 and 12) are acted upon on their side facing away from the roll gap (13) by a respective supporting roll (14, 15), the

Roll pins (25) are preloaded in their roll pin bearings (26) to reduce their bearing play.

57. The use of a device according to one of claims 44 to 55, in which the first roller (11) and the second roller (12) are not acted upon by supporting rollers, but rather the roller journals (21, 22) of the first roller (11) and the second roller (12) in their roll neck bearings (22) are biased to reduce their bearing play.

58. The use of a device according to one of claims 44 to 57, in which the first and the second roller (11, 12) are driven discontinuously, such that they are in synchronism with the pulling device provided on the outlet side of the roll gap (13) during the strip feed (6, 53) are driven, whereas they temporarily stand still and / or are positioned individually or jointly by forward rotation or reverse rotation, if the return device (5, 52) provided on the inlet side of the roll gap (13) for returning the metal strip (16) is reversed is driven.

59. The use of a device according to one of claims 44 to 58, in which the peripheral speed of the two rollers (11, 12) and the speed of the pulling device (6, 53), preferably also that of the return device (5, 52), can be controlled at will are.

60. The use of a device according to one of claims 44 to 59, in which one of the two rollers (12, 13), preferably the upper roller (12), can be shifted up and down in a controlled manner during the rolling.

61. The use of a device according to claim 60, in which one or the other roller (11, 12) can be shifted up and down in a controlled manner during the rolling.

62. The use of a device according to claim 60 or 61, in which one or more servo drives (32, 33, 34, 44) are provided for moving the relevant roller (11, 12).

63. The use of a device according to claim 62, in which the servo drives (32, 33, 34, 44) each comprise an electric motor (34) or one or two short hydraulic cylinders.

64. The use of a device with a roll stand (2) with two rolls (11, 12) which delimit a roll gap (13), the height of which is variable, and with a return device (5,) arranged on the inlet side of the roll gap (13). 52) for a metal strip (16) to be rolled,

why one of the two rollers (11, 12) in the roll stand (2) during the Rolling can be moved up and down in a controlled manner, namely by a path determined by the desired profile depending on the feed of the metal strip (16), and for which purpose a drive motor (5, 52) for the return device (5, 52) provided on the inlet side of the roll gap (13). 7, 54) is provided, which enables the metal strip (16) to be retrieved in steps of a predeterminable length, in particular a servo motor.

65. The use of a device with a roll stand (2) with two rolls (11, 12) which delimit a roll gap (13) and with a return device (5, 52) arranged on the inlet side of the roll gap (13) for one rolling metal strip (16),

for producing a band-shaped primary material made of metal with a high surface quality by the method according to claim 1,

for which purpose a drive motor (7, 54) is provided for the return device (5, 52) provided on the inlet side of the roll gap (13), which enables the metal strip (16) to be returned in steps of a predetermined length, in particular a servo motor.

66. The use of a device according to claim 64 or 65, in which a pulling device (6, 53) for the strip-shaped primary material is arranged on the outlet side of the roll gap (13).

67. The use of a device according to claim 64, 65 or 66, in which the return device is a first reel (5).

68. The use of a device according to claim 64, 65 or 66, in which the return device is a first tong feed device (52).

69. The use of a device according to claim 66, in which the pulling device is a second reel (6) for winding the band-shaped pre-material.

70. Use of a device according to claim 66, in which the pulling device is a second tong feed device (53).

71. The use of a device according to one of claims 60 to 70, in which a servo motor (8, 55) is also provided for the pulling device (6, 53) provided on the outlet side of the roll gap (13).

72. The use of a device according to claim 71, in which an electronic control device (43) is provided, in which the displacement of the one roller (12) required for an intended profile is preferably stored digitally as a curve, and in that this control device (43) the servomotors (7, 8; 54, 55) of the return device (5, 52) and the pulling device (6, 53), one or two servomotors (41, 42) for rotating the two rollers (11, 12) and one or a plurality of adjusting drives (32, 33, 34) coupled to an incremental rotary encoder (44) for the displaceable roller (12) are connected.

73. The use of a device according to one of claims 59 to 72, in which the direction of rotation of the two rollers (11, 12) is reversible for rolling in both directions. The use of a device according to one of claims 50 to 57, in which the displaceable roller (12) has an axially parallel cut (45).