EP2340898A2 - Rolling machine - Google Patents

Abstract

A rolling mill with a new process control has work pieces forged between two profiled rollers. The speed and position is controlled on at least one roller with the rolling speed controlled w.r.t. the position of the work piece. The process cycle comprises a positioning phase at a slow speed, a rolling phase at a higher speed and a final phase in which the work piece is returned at a slower speed.

Description

The invention relates to a method for forming a workpiece and a rolling machine, which is suitable for carrying out the method.

For forming workpieces from a starting shape into a desired intermediate shape (semifinished product, preforming) or final shape (finished product, finished forms), there are, among many other processes, also rolling processes which are counted among the pressure forming processes. During rolling, the workpiece (rolling stock) is placed between two rotating rolls and changed in shape by exerting a forming pressure by the rotating rolls. When profile rolling process tool profiles are arranged on the circumference of the rollers, which allow the production of corresponding profiles in the workpiece. In flat rolling, the cylindrical or tapered outer surfaces of the rollers act directly on the workpiece.

With regard to the relative movement of the tools or rollers on the one hand and the workpiece on the other hand, one divides rolling processes in longitudinal rolls, transverse rolls and oblique rolls. During longitudinal rolling, the workpiece is moved perpendicular to the axes of rotation of the rollers in a translatory movement and usually without rotation through the gap between the rollers (nip). During transverse rolling, the workpiece does not translate with respect to the rollers or their axes of rotation, but rotates only about its own axis, which is usually a main axis of inertia, in particular the axis of symmetry in a rotationally symmetrical workpiece. When combining both types of movement during longitudinal rolling and cross rolling one speaks of skew rolls. The rollers are usually at an angle to each other and to the workpiece, which is translationally and rotationally moved.

Profile transverse rolling machines, in which two rollers with wedge-shaped profile tools arranged on the outer circumference rotate in the same direction about axes of rotation parallel to one another, are sometimes referred to as transverse wedge rolling. The tools have a wedge-shaped or triangular in cross-section geometry and can increase along the circumference in their radial dimension in one direction and / or extend obliquely to the axis of rotation of the rollers.

These cross wedge or cross-profile rollers allow a variety of forming workpieces in high precision or dimensional accuracy. As a result of the compressive force exerted by the wedge-shaped tools on the workpiece while the material distribution in the workpiece during the rotation of the rollers is changed by a flow in the workpiece. The wedge-shaped tools can create circumferential grooves and other tapers in the rotating workpiece. By the axial offset in the circumferential direction or the oblique arrangement of the tool wedges relative to the axis of rotation, for example, axially changing structures and tapers can be produced in the workpiece to the rotation axis. By the increase or decrease of the outer diameter of the tool wedges when passing around the axis of rotation can be generated in combination with the oblique arrangement axially extending slopes and continuous transitions between two tapers of different diameters in the workpiece. The wedge shape of the tools allows the production of fine structures through the wedge outer edges or outer surfaces. Particularly suitable are cross wedge rollers for producing elongate, rotationally symmetrical workpieces with constrictions or elevations such as cams or ribs.

The forming pressure and the forming temperature depend on the material of which the workpiece is made, as well as the dimensional accuracy and surface quality requirements after forming. Especially In iron or steel materials, the forming is usually carried out at elevated temperatures during rolling, in order to achieve the formability or flowability of the material required for forming. These temperatures, in particular occurring during forging, can be in the range of room temperature in the case of so-called cold forming, or between 550 ° C. and 750 ° C. in the case of warm forging, and above 900 ° C. in the case of so-called hot forming. The forming or forging temperature is usually also placed in a temperature range in which run recovery and recrystallization processes in the material and unwanted phase transformations are avoided.

Cross wedge rolling machines are known, in which the workpieces at the beginning of the rolling process by means of a positioning device comprising two positioning supports (so-called guide rulers), in an initial position between the two rollers, which usually corresponds to the geometric center or the center of the nip , positioned. Now, the positioning carriers of the positioning device are withdrawn, so that the workpiece rotates freely between the rollers and is kneaded between the tools in the desired shape. After this rolling or kneading process and the corresponding completion of the workpiece, the workpiece is detected and ejected via a recess in the rotating rolling tool.

Out DE 1 477 088 C is a cross wedge rolling machine for the transverse rolling of bodies of revolution or flat workpieces with two rotating in the same direction of rotation work rolls on the roll surfaces wedge tools are arranged interchangeable. The wedge tools each have wedge-shaped or triangular extending from the roll shell to a height adjusted to the produced workpiece end, by knurling or otherwise roughened reduction strips and extending at the same distance from the roll shell, wedge-shaped smooth form surfaces with calibration effect. The wedge tools are formed as deformation segments and extend only over a partial circumference of the associated roll surface. On the workpiece The mutually facing surfaces and tools of the two work rolls move in opposite directions or in opposite directions to each other.

The EP 1 256 399 A1 discloses a cross rolling machine with two parallel operated modules of two rollers rotating in the same direction of rotation, the half-shell-shaped tools having radially projecting tool wedges on its peripheral surface, wherein the deformation of a workpiece requires only the rotation of half the circumference of a pair of rollers. All four rollers are driven by only one drive motor via an interposed gear unit and drive shaft.

From the DE 195 26 071 A1 is a device for rolling profiles in a workpiece, in particular transverse rolls, longitudinal rolls and helical rolls of threads, knurls, Zahnwalzprofile or the like, known with two forming rollers which are rotated about mutually parallel axes of rotation in the same direction of rotation and each driven by an associated drive with drive motor be, with each drive is assigned a braking device.

The DE 21 31 300 B discloses a cross rolling machine with two axially parallel horizontal superimposed profiled rollers for forming and cutting rotationally symmetrical workpieces, in which the profile rollers touch the workpieces diametrically opposite circumferential points and the lower profile roller has a recess for discharging the rolled and cut workpieces from the nip.

The invention is based on the object of specifying a new rolling machine.

This object is achieved with the features of claim 1.

The rolling machine according to claim 1 comprises for each of the rollers an associated drive, wherein the drives are independent of each other, and comprises at least one permanent magnet motor, in particular a torque motor for driving the rollers.

Advantageous embodiment and development of the rolling machine resulting from the dependent of claim 1 claims.

In a particularly advantageous embodiment, the rolling machine is a profile cross rolling machine or cross wedge rolling machine. Due to the speed-controllable and reversible drive, the rolling or cross wedge rolling machine can also be used as a stretching or short stretch roll.

The permanent magnet motor preferably accelerates to the rated speed for operation of the rollers within a rotation angle of a maximum of 3 °, 2.2 °, 1 ° or 0.5 °. Furthermore, the permanent magnet motor preferably has a nominal torque between about 5,000 Nm and about 80,000 Nm, in particular between about 35,000 Nm and about 60,000 Nm, and / or a rated speed between about 20 U / min and 800 U / min, in particular about 30 U / min or 500 rpm.

In a development of the rolling machine, the drive comprises, in addition to the at least one permanent magnet motor, at least one transmission for transmitting the torque or the rotational movement of the permanent magnet motor to the at least two rollers. In particular, the transmission comprises at least one central drive gearwheel coupled to the output shaft of the permanent magnet motor and two roller gearwheels which engage or can be brought into engagement with the drive gearwheel and are coupled to one of the rollers. The gear ratio of the transmission from the drive motor to each of the rollers is then generally the same, and preferably selected in a range between 1: 1 and 1: 1.5. Such a drive is therefore in particular mechanically synchronized via the transmission.

In independent drives for the rollers, however, the rollers are electronically synchronized or controlled, in particular via inverters, which convert, for example, a mains voltage of 400 V and 50 Hz in an AC voltage or an AC of suitable amplitude and frequency. Here is particularly advantageous that in cross wedge rollers, the force load on both motors because of the symmetrical structure of the tools / rollers and / or the symmetrical forming process is relatively low and thus the synchronization of the drives is favored.

1. 1. Verfahren zum Umformen eines Werkstücks, bei dem
   1. a) das Werkstück zwischen wenigstens zwei rotierenden, mit Werkzeugen bestückten Walzen angeordnet wird und
   2. b) die Rotationsgeschwindigkeit wenigstens einer der Walzen in Abhängigkeit von der Drehposition wenigstens einer der Walzen gesteuert oder geregelt wird.

The following claims from the parent application as filed could also be (partially) the subject of the present divisional application:

1. 1. A method for forming a workpiece, wherein
   1. a) the workpiece between at least two rotating, equipped with tools rollers is arranged and
   2. b) the rotational speed of at least one of the rollers is controlled or regulated as a function of the rotational position of at least one of the rollers.

1. a) Anordnen des Werkstücks zwischen wenigstens zwei rotierenden, mit Werkzeugen versehenen (bestückten) Walzen und
2. b) Einstellen (Steuern oder Regeln) der Rotationsgeschwindigkeit, insbesondere der Winkelgeschwindigkeit, Drehzahl oder Umfangsgeschwindigkeit, wenigstens einer der Walzen in Abhängigkeit von der Drehposition wenigstens einer der Walzen.

The method for forming a workpiece accordingly comprises the following method steps:

1. a) arranging the workpiece between at least two rotating, provided with tools (equipped) rollers and
2. b) adjusting (controlling or regulating) the rotational speed, in particular the angular speed, rotational speed or circumferential speed, of at least one of the rollers as a function of the rotational position of at least one of the rollers.

• 2. Verfahren nach Anspruch 1, bei dem die Abhängigkeit der Rotationsgeschwindigkeit von der Drehposition der Walze(n) abhängig vom bearbeiteten Werkstück gewählt ist.
• 3. Verfahren nach Anspruch 1 oder Anspruch 2, bei dem das Werkstück
  1. a) während einer ersten Prozessphase, vorzugsweise mittels einer Positioniereinrichtung, zwischen den Walzen positioniert wird,
  2. b) während einer zweiten Prozessphase zwischen den Werkzeugen der Walzen umgeformt wird und
  3. c) während einer dritten Prozessphase wieder aus dem Zwischenraum zwischen den Walzen entnommen oder ausgeworfen wird.
• 4. Verfahren nach Anspruch 3, bei dem die Rotationsgeschwindigkeit in der ersten Prozessphase wenigstens im Mittel geringer ist als während der zweiten Prozessphase und/oder bei dem die Rotationsgeschwindigkeit der Walzen während der zweiten Prozessphase zumindest im Mittel größer ist als während der dritten Prozessphase.
• 5. Verfahren nach Anspruch 3 oder Anspruch 4, bei dem das Werkstück zu Beginn der zweiten Prozessphase von dem oder den Werkzeug(en) wenigstens einer Walze erfasst wird und während der zweiten Prozessphase zwischen den Werkzeugen der beiden Walzen umgeformt wird und zu Beginn der dritten Prozessphase aus dem Zwischenraum zwischen den Walzen ausgeworfen wird.
• 6. Verfahren nach Anspruch 5, bei dem die Rotationsgeschwindigkeit nach Erfassen des Werkstückes durch die Werkzeuge der Walze(n) in der zweiten Prozessphase erhöht wird und/oder bei dem die Rotationsgeschwindigkeit vor dem Auswerfen des Werkstückes in der dritten Prozessphase erniedrigt wird und/oder bei dem die Rotationsgeschwindigkeit beim Erfassen des Werkstückes zu Beginn der zweiten Prozessphase und zum Ende der zweiten Prozessphase etwa gleich ist.
• 7. Verfahren nach einem oder mehreren der Ansprüche 3 bis 6, bei dem die Rotationsgeschwindigkeit wenigstens einer der Walzen während der zweiten Prozessphase zumindest teilweise konstant gehalten wird oder bei dem die Rotationsgeschwindigkeit wenigstens einer der Walzen während der zweiten Prozessphase, insbesondere gemäß einem vorgegebenen Verlauf oder einer vorgegebenen Abhängigkeit, verändert wird.
• 8. Verfahren nach einem der Ansprüche 3 bis 7, bei dem die zweite Prozessphase einzelne Teilprozessphasen umfasst, während der vorzugsweise das Werkstück von verschiedenen Werkzeugen auf den Walzen umgeformt wird, wobei vor oder nach einer Teilprozessphase und/oder zwischen den Teilprozessphasen und/oder während der Teilprozessphasen die Rotationsgeschwindigkeit verändert wird und/oder wobei die Rotationsgeschwindigkeit vor wenigstens einer oder vor jeder, Teilprozessphase reduziert wird.
• 9. Verfahren nach einem oder mehreren der vorhergehenden Ansprüche, bei dem die Rotationsgeschwindigkeit und/oder Drehrichtung der Walzen wenigstens phasenweise im Wesentlichen gleich zueinander eingestellt werden bzw. wird und/oder bei dem die Rotationsgeschwindigkeit und/oder Drehrichtung der Walzen wenigstens phasenweise unterschiedlich zueinander eingestellt werden bzw. wird.
• 10. Verfahren nach einem oder mehreren der vorhergehenden Ansprüche, bei dem die aktuelle Drehposition der Walze(n) aus einer Ausgangsposition oder Referenzposition der Walze(n) und dem Verlauf der Rotationsgeschwindigkeit ermittelt wird oder bei dem die Drehposition der Walze(n) mittels wenigstens einer Positionserfassungseinrichtung bestimmt wird.
• 11. Verfahren nach einem oder mehreren der vorhergehenden Ansprüche, bei dem die Rotationsgeschwindigkeit bei wenigstens einer Drehposition verringert wird, um eine Überbeanspruchung des Werkstücks bei dieser Drehposition zu vermeiden, und/oder bei dem die Rotationsgeschwindigkeit bei wenigstens einer Drehposition so gesteuert oder geregelt wird, dass das auf die zugehörige Walze ausgeübte Drehmoment bei dieser Drehposition einen vorgegebenen Wert annimmt oder nicht überschreitet.
• 12. Verfahren nach einem oder mehreren der vorhergehenden Ansprüche, bei dem die aktuelle Position der Werkzeuge auf den Walzen bestimmt wird und eine Referenzdrehposition der Walzen abhängig von der bestimmten aktuellen Position der Werkzeuge eingestellt wird.
• 13. Verfahren nach einem oder mehreren der vorhergehende Ansprüche, bei dem das Werkstück kaltumgeformt oder warmumgeformt oder heißumgeformt wird und/oder bei dem das Werkstück aus einem eisenhaltigen Werkstoff oder aus einem nicht eisenhaltigen metallischen Werkstoff besteht.
• 14. Walzmaschine, insbesondere zum Durchführen eines Verfahrens nach einem der vorhergehenden Ansprüche, mit
  1. a) wenigstens zwei rotierbaren oder rotierenden, mit Werkzeugen bestückbaren oder bestückten Walzen zum Umformen eines zwischen den Walzen anordenbaren oder angeordneten Werkstücks,
  2. b) wenigstens einem Antrieb zum Antreiben der Walzen, wobei
  3. c) der wenigstens eine Antrieb wenigstens einen Permanentmagnet-Motor, insbesondere einen Torque-Motor, umfasst.
• 15. Walzmaschine nach Anspruch 14, bei der jeder Permanentmagnet-Motor auf die Nenndrehzahl zum Betrieb der Walze(n) innerhalb eines maximalen Drehwinkelintervalls von höchstens 3° oder von höchstens 2,2° oder höchstens 1° oder sogar höchstens 0,5° beschleunigt oder verzögert.
• 16. Walzmaschine nach Anspruch 14 oder Anspruch 15, bei der wenigstens ein oder jeder Permanentmagnet-Motor ein Nenndrehmoment zwischen etwa 5.000 Nm und etwa 80.000 Nm oder zwischen etwa 35.000 Nm und etwa 60.000 Nm aufweist und/oder bei der wenigstens ein oder jeder Permanentmagnet-Motor eine Nenndrehzahl zwischen etwa 20 U/min und 800 U/min oder zwischen etwa 30 U/min und 500 U/min aufweist.
• 17. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 16, bei der ein gemeinsamer Antrieb für wenigstens zwei der Walzen vorgesehen ist, der neben dem wenigstens einen Permanentmagnet-Motor wenigstens ein Getriebe umfasst zur Übertragung der Drehkraft oder der Drehbewegung des Permanentmagnet-Motors auf die wenigstens zwei Walzen, wobei vorzugsweise das Getriebe wenigstens ein mit der Abtriebswelle des Permanentmagnet-Motors gekoppeltes zentrales Antriebszahnrad sowie zwei mit dem Antriebszahnrad in Eingriff stehende oder bringbare und mit jeweils einer der Walzen gekoppelte Walzenzahnräder umfasst und/oder vorzugsweise das Übersetzungsverhältnis des Getriebes vom Antriebsmotor auf jede der Walzen gleich ist oder in einem Bereich zwischen 1 : 1 und 1 : 1,5 liegt.
• 18. Walzmaschine nach Anspruch 17, bei der das Zahnflankenspiel oder der Zahneingriff der Walzenzahnräder zum Antriebszahnrad einstellbar oder korrigierbar ist, vorzugsweise Mittel zum Bewegen des Antriebszahnrades, vorzugsweise zusammen mit dem Permanentmagnet-Motor, relativ zu den Walzenzahnrädern vorgesehen sind, insbesondere wenigstens ein Verstellantrieb.
• 19. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 18 mit Mitteln zum Einstellen der relativen Winkelposition der beiden Walzen zueinander, die vorzugsweise ein mit einer der Walzen gekoppeltes Schneckenrad umfassen.
• 20. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 19 und/oder zum Durchführen eines Verfahrens nach einem der Ansprüche 1 bis 13 mit
  1. a) wenigstens zwei rotierbaren oder rotierenden, mit Werkzeugen bestückbaren oder bestückten Walzen zum Umformen eines zwischen den Walzen anordenbaren oder angeordneten Werkstücks,
  2. b) wobei jeder Walze wenigstens ein Antrieb zugeordnet ist zum unabhängigen Antreiben der Walzen.
• 21. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 20, bei der wenigstens ein Antrieb einen Umrichter zum Versorgen des Motors mit elektrischer Energie aufweist.
• 22. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 21, umfassend wenigstens eine Positionserfassungseinrichtung zum Erfassen oder Bestimmen der Drehposition wenigstens einer der Walzen.
• 23. Walzmaschine nach einem oder mehreren der Ansprüche 14 bis 22, die als Profilquerwalzmaschine oder Querkeilwalzmaschine ausgebildet ist und/oder bei der die Walzen im Querschnitt keilförmige oder dreieckförmige Profilwerkzeuge aufweisen, die entlang des Umfangs in ihrer radialen Abmessung in einer Richtung zunehmen und/oder schräg zur Drehachse der zugehörigen Walze verlaufen.

The term "forming" is understood to mean any transformation of the shape of a workpiece into another form, as also described at the outset, including preforming and finish forming.

• 2. The method of claim 1, wherein the dependence of the rotational speed of the rotational position of the roller (s) is selected depending on the machined workpiece.
• 3. The method of claim 1 or claim 2, wherein the workpiece
  1. a) is positioned between the rollers during a first process phase, preferably by means of a positioning device,
  2. b) is formed during a second process phase between the tools of the rolls and
  3. c) is removed or ejected again from the space between the rollers during a third process phase.
• 4. The method of claim 3, wherein the rotational speed in the first process phase is at least on average less than during the second process phase and / or in which the rotational speed of the rollers during the second process phase is at least on average greater than during the third process phase.
• 5. The method of claim 3 or claim 4, wherein the workpiece is detected at the beginning of the second process phase of the tool or tools at least one roller and is formed during the second process phase between the tools of the two rolls and at the beginning of the third Process phase is ejected from the space between the rollers.
• 6. The method of claim 5, wherein the rotation speed after detecting the workpiece by the tools of the roller (s) is increased in the second process phase and / or in which the rotational speed is lowered before ejecting the workpiece in the third process phase and / or wherein the rotational speed when detecting the workpiece at the beginning of the second process phase and the end of the second process phase is about the same.
• 7. The method according to one or more of claims 3 to 6, wherein the rotational speed of at least one of the rollers during the second process phase is kept at least partially constant or in which the rotational speed of at least one of the rollers during the second process phase, in particular according to a predetermined course or a given dependence, is changed.
• 8. The method according to any one of claims 3 to 7, wherein the second process phase includes individual sub-process phases, during which preferably the workpiece is formed by different tools on the rollers, wherein before or after a sub-process phase and / or between the sub-process phases and / or during the sub-process phases, the rotational speed is changed and / or wherein the rotational speed is reduced before at least one or before each, sub-process phase.
• 9. The method according to one or more of the preceding claims, wherein the rotational speed and / or direction of rotation of the rollers are set at least in phases substantially equal to each other and / or in which set the rotational speed and / or direction of rotation of the rollers at least in phases different from each other be or will.
• 10. The method according to one or more of the preceding claims, wherein the current rotational position of the roller (s) from a starting position or reference position of the roller (s) and the course of the rotational speed is determined or in which the rotational position of the roller (s) by means of at least a position detection device is determined.
• 11. The method according to one or more of the preceding claims, wherein the rotational speed is reduced in at least one rotational position to overstress the workpiece in this To avoid rotational position, and / or in which the rotational speed in at least one rotational position is controlled or regulated so that the force exerted on the associated roller torque at this rotational position assumes a predetermined value or not.
• 12. The method according to one or more of the preceding claims, wherein the current position of the tools is determined on the rollers and a reference rotational position of the rollers is adjusted depending on the determined current position of the tools.
• 13. The method according to one or more of the preceding claims, wherein the workpiece is cold-formed or hot-formed or hot-formed and / or wherein the workpiece consists of a ferrous material or of a non-ferrous metal material.
• 14. Rolling machine, in particular for carrying out a method according to one of the preceding claims, with
  1. a) at least two rotatable or rotating, can be fitted with tools or equipped rollers for forming a can be arranged between the rollers or arranged workpiece,
  2. b) at least one drive for driving the rollers, wherein
  3. c) the at least one drive comprises at least one permanent magnet motor, in particular a torque motor.
• 15. A rolling machine according to claim 14, wherein each permanent magnet motor accelerates to the rated speed for operation of the roll (s) within a maximum rotation angle interval of at most 3 ° or at most 2.2 ° or at most 1 ° or even at most 0.5 ° or delayed.
• 16. Rolling machine according to claim 14 or claim 15, wherein the at least one or each permanent magnet motor has a nominal torque of between about 5,000 Nm and about 80,000 Nm or between about 35,000 Nm and about 60,000 Nm and / or wherein at least one or each permanent magnet Motor has a rated speed between about 20 U / min and 800 U / min or between about 30 U / min and 500 U / min.
• 17. Rolling machine according to one or more of claims 14 to 16, wherein a common drive is provided for at least two of the rollers, in addition to the at least one permanent magnet motor comprises at least one gear for transmitting the rotational force or the rotational movement of the permanent magnet motor the at least two rollers, wherein preferably the transmission comprises at least one coupled to the output shaft of the permanent magnet motor central drive gear and two meshing with the drive gear or engageable and coupled to each one of the rollers roller gears and / or preferably the transmission ratio of the transmission from the drive motor is equal to each of the rolls or is in a range between 1: 1 and 1: 1.5.
• 18. Rolling machine according to claim 17, wherein the backlash or the meshing of the roller gears to the drive gear is adjustable or correctable, preferably means for moving the drive gear, preferably provided together with the permanent magnet motor, relative to the roller gears, in particular at least one adjustment.
• 19. Rolling machine according to one or more of claims 14 to 18 with means for adjusting the relative angular position of the two rollers to each other, which preferably comprise a coupled with one of the rollers worm wheel.
• 20. Rolling machine according to one or more of claims 14 to 19 and / or for carrying out a method according to any one of claims 1 to 13 with
  1. a) at least two rotatable or rotating, can be fitted with tools or equipped rollers for forming a can be arranged between the rollers or arranged workpiece,
  2. b) wherein each roller is associated with at least one drive for independently driving the rollers.
• 21. Rolling machine according to one or more of claims 14 to 20, wherein at least one drive comprises a converter for supplying the motor with electrical energy.
• 22. Rolling machine according to one or more of claims 14 to 21, comprising at least one position detecting means for detecting or determining the rotational position of at least one of the rollers.
• 23. Rolling machine according to one or more of claims 14 to 22, which is designed as a profile cross rolling or cross wedge rolling machine and / or in which the rollers in cross-section wedge-shaped or triangular profile tools, which increase along the circumference in their radial dimension in one direction and / or run obliquely to the axis of rotation of the associated roller.

FIG 1

eine Walzmaschine mit zwei Walzen und einem gemeinsamen Antrieb in einer teilweise geschnittenen Längsansicht,

FIG 2

die Walzmaschine gemäß FIG 1 in einer teilweise geschnittenen Draufsicht von oben,

FIG 3

die Walzmaschine gemäß FIG 1 und FIG 2 in einer Seitenansicht,

FIG 4

die beiden Arbeitswalzen einer Walzmaschine im Querschnitt vor Einbringen des Werkstückes,

FIG 5

die beiden Arbeitswalzen der Walzmaschine beim Einbringen des Werkstückes,

FIG 6

die Arbeitswalzen mit dem bearbeiteten Werkstück im Querschnitt,

FIG 7

die beiden Arbeitswalzen beim Auswerfen des Werkstückes und

FIG 8

eine mögliche Abhängigkeit der Winkelgeschwindigkeit einer Arbeitswalze vom Drehwinkel in einem Diagramm

FIG 9

eine weitere mögliche Abhängigkeit der Winkelgeschwindigkeit einer Arbeitswalze vom Drehwinkel in einem Diagramm

FIG 10

eine Ausführungsform einer Walzmaschine mit zwei Walzen und unabhängigen Antrieben für die Walzen in einer teilweise geschnitten Längsansicht und

FIG 11

die Walzmaschine gemäß FIG 10 in einer Seitenansicht,

jeweils schematisch dargestellt sind. Einander entsprechende Teile und Größen sind in den FIG 1 bis 11 mit denselben Bezugszeichen versehen.The invention will be explained below with reference to exemplary embodiments. Reference is made to the drawings, in which

FIG. 1

a rolling machine with two rolls and a common drive in a partially sectioned longitudinal view,

FIG. 2

the rolling machine according to FIG. 1 in a partially sectioned top view from above,

FIG. 3

the rolling machine according to 1 and FIG. 2 in a side view,

FIG. 4

the two work rolls of a rolling machine in cross section before introduction of the workpiece,

FIG. 5

the two work rolls of the rolling machine when introducing the workpiece,

FIG. 6

the work rolls with the machined workpiece in cross section,

FIG. 7

the two work rolls when ejecting the workpiece and

FIG. 8

a possible dependence of the angular velocity of a work roll on the angle of rotation in a diagram

FIG. 9

Another possible dependence of the angular velocity of a work roll from the angle of rotation in a diagram

FIG. 10

an embodiment of a rolling machine with two rolls and independent drives for the rolls in a partially cut longitudinal view and

FIG. 11

the rolling machine according to FIG. 10 in a side view,

are each shown schematically. Corresponding parts and sizes are in the 1 to 11 provided with the same reference numerals.

The in the 1 to 3 illustrated embodiment of a designed as a cross wedge roller or cross wedge rolling machine 1 comprises a first work roll 2 which is rotatable about an axis of rotation A or rotating and a second work roll 3, which is rotatable about a rotational axis B or rotating. The sense of rotation of both work rolls 2 and 3 is illustrated and the same with the arrows shown. The axes of rotation A and B are arranged substantially parallel to each other, in the example of 1 to 3 seen in the direction of gravity on top of each other, so that the work rolls 2 and 3 are arranged one above the other. The work rolls have a substantially cylindrical outer surface. The distance between the cylindrical outer surfaces of the two work rolls 2 and 3 is designated by W.

On the outer surface or lateral surface of the work rolls 2 and 3 wedge-shaped tools 20 and 21 or 30 and 31 are respectively fixed in cross-section, in particular braced. In the illustrated embodiment, the tools 20 and 21 of the first work roll 2 and the tools 30 and 31 of the second work roll 3 are each oblique and at an angle to the respective one Rotary axis A and B are arranged, wherein the tools 20 and 21 of the work roll 2 with respect to the parallel between the two rollers parallel to the axes of rotation extending, the geometric center defining central axis M are arranged axially in the substantially same positions. The tools 20 and 21 and 30 and 31 take in the circumferential direction seen in its cross section, wherein the increase of the cross section in the tools 20 and 21 in the same direction of rotation or orientation and in the tools 30 and 31 of the second work roll 3 opposite or opposite directions to which the tools 20 and 21 of the first work roll 2 is.

Each work roll 2 and 3 is releasably held in a two-part holding device and can be removed from the holding device in its unlocked state to replace the tools 20 and 21 or 30 and 31 or the entire work rolls 2 and 3 with the tools 20 and 21 and 30 and 31. The holding device for the work roll 2 is denoted by 12 and the holding device for the work roll 3 with 13. A in 1 and 2 The left-hand arranged first part 12A of the holding device 12 comprises a conical receptacle 14 for receiving a axially to the rotation axis A outwardly from the work roll 2 extending frusto-conical extension 24 (stub shaft). The second part 12B accordingly comprises a receptacle 15 for receiving a corresponding conically tapered away from the work roll 2 and axially to the axis of rotation A extending extension 25 of the work roll 2. Under the resulting wedge and clamping action, the work roll 2 is fixed in the receptacles 14 and 15 of the holding device 12 clamped, wherein the axial force is generated on the receptacle 15 in the direction of the axis of rotation A to the work roll 2 towards the support of the work roll 2 by a spring 16 or other an axial force-exerting element. The receptacles 14 and 15 are rotationally symmetrical to the axis of rotation A and stored in unspecified pivot bearings.

The receptacle 14 continues as a hollow shaft axially to the axis of rotation A and has in its facing away from the work roll 2 end portion of a gear 18, which as well as a corresponding gear 19, the second work roll 3 is associated with a control gear (pinion, drive gear) 5 is engaged. The gear 18, which serves to drive the first work roll 2 via the holding device 12, engages from above into the control gear 5 and the gear 19, which is coupled to the second work roll 3 via the holding device 13, engages from below into the control gear fifth ,

The control gear 5 is now coupled via an output shaft 45 with a drive motor 4. The control gear 5, the output shaft 45 and the - not shown - rotor of the drive motor 4 are rotatable about a common axis of rotation R or rotating. The built-up of the drive motor 4, the output shaft 45 and the control gear 5 drive for the gears (roller gears) 18 and 19 and thus the synchronously with the gears 18 and 19 rotating work rolls 2 and 3 is thus a direct drive.

The mechanical power supplied by the drive motor 4 corresponds to the product of torque and angular velocity or angular frequency ω, the angular frequency ω being equal to the product of 2π and the rotational speed n. The drive motor 4 is preferably a torque motor and has a high torque even at a comparatively low speed n of the drive motor 4 for generating the required drive power for the drive rollers 2 and 3.

The transmission ratio of the control gear 5 to the gears 18 and 19 can thus be selected in the range of 1, in particular between about 1: 1 and about 1: 2. At a transmission ratio of 2, the drive rollers 2 and 3 rotate twice as fast as that Control gear 5 and the drive motor 4, at a transmission ratio of 1: 1 just as fast. Typical speeds of work rolls 2 and 3 are between about 10 revolutions per minute (RPM) and about 40 RPM, typically at 15 RPM.

With such a low-speed or low-speed rotating drive motor 4, a very dynamic adaptation or control or regulation of the speed of the work rolls 2 and 3 can now be realized.

A preferred embodiment of the drive motor 4 is a permanent magnet motor, in which, usually on the rotor, permanent magnets (permanent magnets) are arranged, which generate a magnetic flux generated in the induction field generated by electromagnets or windings of the stator, wherein by interaction of the magnetic flux of the permanent magnets and the induction field, the rotation of the rotor on the basis of the induction principle or electromotive principle arises. In general, a torque motor is a synchronous motor, that is, the rotor rotates synchronously with the rotating magnetic flux. The induction windings of the stator are usually connected to the phases of a three-phase connection and arranged offset by 120 ° to each other. Preferably, permanent magnets are used with the highest possible energy product, such as rare earth cobalt magnets. The stator usually has an iron core with the three-phase winding package, while the rotor has a cylindrical iron core with the permanent magnets. Such a torque motor can have a torque of up to 80,000 Nm. The high torque also causes a very fast spin. In particular, the permanent magnet motor or torque motor can accelerate the rollers within a rotation angle of only 1 °, preferably even only 0.5 °, to the rated speed, for example 30 rpm. This high dynamics or rotational acceleration of the torque motor allows a very dynamic control of the speed.

The control or regulation of the speed n of each other and synchronously rotating work rolls 2 and 3 is now adapted according to the invention with a special control method or control method to the rolling process. For this purpose, the rotational speed n or angular velocity ω of the work rolls 2 and 3 is adapted to the respective rotational position or angular position φ of the work rolls 2 and 3 and controlled in dependence on this rotational position φ.

Thus, depending on the respective process, the respective rolling machine and, above all, depending on the workpiece to be machined, the deformation by the work rolls 2 and 3 can be optimized by controlling the rotational speed n or the angular velocity ω = dφ / dt.

The 4 to 7 Now show a possible sequence of a rolling process with such a rotational position-dependent speed control or regulation in a workpiece 10. A positioning device for the workpiece 10 is designated 60 and comprises two relatively movable positioning parts (guide rulers) 61 and 62nd

FIG. 4 shows a position of the work rolls 2 and 3 before the introduction of the workpiece. The same direction of rotation of the two rollers 2 and 3 about the respective axes of rotation A and B are marked with corresponding arrows. In the tool 20, which extends in segments around the outer surface of the work roll 2 and about the axis of rotation A, a recess 23 is provided. In the second work roll 3, a further recess 33 is also provided in the segment-like tool 30.

The workpiece 10 is now taught by means of two guide ruler of a positioning device not shown in a position between the work rolls 2 and 3, in which it is detected by the recess 23 in the tool 20 of the first work roll 2. This process phase with incorporated tool 10 in the starting position shows FIG. 5 , On the workpiece 10, the mutually facing surfaces of the work rolls 2 and 3 move in opposite directions or opposite to each other.

Upon further rotation of the work rolls 2 and 3 to each other, the workpiece 10 is now placed between the tools 20 and 30 and under the pressure of the tools 20 and 30, which have a smaller distance w to each other than the original diameter of the workpiece 10 in a smaller diameter spent. The resulting after forming reduced diameter (recess) of the workpiece 10 at the in cross section The position shown corresponds largely to the minimum distance w between the tools 20 and 30 of the work rolls 2 and 3. A position of the work rolls 2 and 3 with the intermediate kneaded workpiece 10 during the actual rolling process is in FIG. 6 shown.

In FIG. 7 Finally, the position of the work rolls 2 and 3 is illustrated, in which the workpiece 10 falls into the recess 33 of the tool 30 of the second work roll 3 and, upon further rotation of the work roll 3, is ejected from the gap between work rolls 2 and 3.

Thus, in the rolling process, it is fundamentally possible to distinguish three process phases, namely a first process phase for preparing the rolling process and positioning the workpiece in the starting position, that is to say a process phase which occurs in the process 4 and 5 is shown, further a second process phase, during which the actual rolling process takes place and the workpiece is formed between tools of the two work rolls, according to FIG. 6 , and finally a third process phase, during which the workpiece is removed again from the tools, accordingly FIG. 7 ,

FIG. 8 now shows a diagram in which the speed n of the work rolls 2 and 3 as a direct measure of the rotational speed in the unit Hertz (Hz) = 1 / s or in revolutions per second (or: revolutions per minute) on the rotational position or the angle of rotation φ of the work roll 2 is applied. There are nine consecutive angular positions φ1 to φ9 drawn on the φ-axis and between the angular positions φ1 and φ9 the rotational speed n as a function of n (φ) of the rotational angle φ plotted. The resulting curve is labeled K. This curve K is in turn subdivided into seven sub-curves K1 to K7, the first sub-curve K1 between the angular positions φ1 and φ2, the second sub-curve K2 between the angular positions φ2 and φ3, the third sub-curve K3 between the angular positions φ3 and φ4, the fourth sub-curve K4 between the angular positions φ4 and φ5, the fifth sub-curve K5 between the angular positions φ5 and φ6, the sixth sub-curve K6 between the angular positions φ6 and φ7 and the seventh sub-curve K7 is between the angular positions φ7 and φ8. The first part curve K1 and the second part curve K2 show a possible time profile of the speed n of the work rolls 2 and 3 in the lying between the angular positions φ1 and φ3 first process phase for preparation and positioning of the workpiece 10. Between the angular positions φ1 and φ2 is in a quite steep rise according to the sub-curve K1 increases the speed from 0 to a first speed n1> 0 and then held substantially constant between the angular positions φ2 and φ3, corresponding to the part curve K2. In the period between φ2 and φ3, corresponding to the part curve K2, the workpiece 10 is positioned between the work rolls 2 and 3 and finally detected at approximately the angular position φ3 of the recess 23 of the tool 20 of the first work roll 2.

The angular position φ3 is now the angular position of the first rotary roller 2, in which the workpiece 10 is fixed in the recess 23 and the rolling process can begin. It should be noted that the angular position or rotational position of the second work roll 3 is directly correlated with the angular position of the work roll 2 and changes synchronously, but in opposite directions with the angular position of the first work roll, wherein the rotation of the work rolls 2 and 3 takes place in the same direction. Therefore, it is sufficient to consider the rotational position of the first work roll 2. Of course, it could just as the angular position of the second work roll 3 are taken as a variable or parameter, of which the speed n is made dependent. In any case, it is sufficient to provide on one of the two work rolls 2 or 3 a position detection device for determining the angle of rotation φ relative to a reference or zero position φ0, which in the 4 to 7 is selected down and drawn.

Upon reaching the angular position φ3 and the engagement of the workpiece 10 in the recess 23, the rotational speed n between the angular position φ3 and a subsequent angular position φ4 is now increased rapidly in the curve section K3 with a correspondingly high rotational acceleration or slope of the characteristic K. The angular position φ4 is then reaches a higher speed n2, on which the speed n during the part curve K4 up to a new one Angular position φ6 is held. This partial curve K4 between the angular positions φ4 and φ6 marks the actual rolling process. The FIG. 6 shows a snapshot of this rolling cut to the angular position φ5 of the work roll second

Shortly before the recess 33 of the tool 30 of the second work roll 3 reaches the workpiece 10, the rotational speed n is reduced again during the part curve K5, preferably again with a angle φ6 of the first work roll 2 lying in front of the associated angular position φ7 of the first work roll 2 high braking acceleration and then with a lower braking acceleration, corresponding to a flatter slope in the sub-curve K6 between the angular positions φ7 and φ8 further lowered. It is therefore carried out the ejection of the workpiece at a lower speed n and a lower spin to gently eject the workpiece. The ejection of the workpiece is completed at the end of the part curve K6 at the angular position φ8 of the first work roll 2 and the rotational speed n is now at the termination of the machining process of this workpiece 10 between the rotation angles φ8 and φ9 corresponding to the part curve K7 back to speed n = 0 Hz scaled back. A work cycle or a forming process is thus completed.

Of course, other angular position-dependent profiles of the speed n can be driven. So it is also possible to rotate the two work rolls 2 and 3 during partial phases of the process with mutually different speeds or even different directions of rotation. Further, depending on the number and arrangement of the tools on the work rolls, the profile n (φ) can be controlled.

FIG. 9 shows a dependence n (φ), during which a more complicated profile is driven during the forming process. First, starting from the angular position φ0 and a rotational speed n = n2, decelerated to a rotational speed n1 at an angular position φ1. This rotational speed n1 is maintained up to an angular position φ2 and then back to the rotational speed n2 at the angular position accelerates φ3 and maintain this speed n2 up to the angular position φ4. This lowering of the rotational speed n is advantageous when threading or gripping the workpiece 10. For a first forming phase with a first tool is now accelerated between the angular positions φ4 and φ5 of a speed n2 to a higher speed n8 and maintain this speed n8 up to an angular position φ6. Then is braked again from the speed n8 to a speed n5 between the angular positions φ6 and φ7. The rotational speed n5 is maintained between the angular positions φ7 and φ8 and then accelerated again between φ8 and φ9 to a rotational speed n7, which is maintained again during a plateau phase between φ9 and φ10. This plateau phase between φ9 and φ10 with the speed n7 corresponds to another forming phase with another tool. Finally, braked again by the rotational speed n7 to a rotational speed n4 between the angular positions φ10 and φ11, the rotational speed n4 up to the angular position φ12 maintained and then accelerated again to a rotational speed n6 in the interval between φ12 and φ13. The speed n6 is kept constant up to the angular position φ14. Then it is again accelerated to a maximum speed n9 between the angular positions φ14 and φ16 and the speed n9 is maintained during a final forming phase between φ16 and φ17. Finally, at the end of the forming process, between φ17 and φ18 is decelerated to the original speed n2. We have 0 <n1 <n2 <n3 <n4 <n5 <n6 <n7 <n8 <n9.

Like the profiles according to FIG. 8 and 9 show, the angle-dependent speed control according to the invention allows a variety of adapted rolling rotational movements for different processes, tools and workpieces.

FIG. 1 and 3 further show a worm wheel 9, which is coupled to the gear 18 for the work roll 2 and allows adjustment or adjustment of the relative angular position of the work roll 2 relative to the work roll 3. Thus, in adaptation to different tools or for correction, the angular positions of the work rolls 2 and 3 can be adjusted relative to each other.

For setting or correcting the backlash or tooth engagement between the roller gears 18 and 19 and the central control gear 5 may also be provided an adjusting drive, not shown, the rotational drive with the permanent magnet motor 4 and the transmission to the output shaft 45 and the control gear 5 relative to can move the two roller gears 18 and 19. As a result, an asymmetric engagement or backlash can be corrected. Furthermore, it is also possible to provide separate drives for adjusting the rollers 2 and 3 with their roller gears 18 and 19, so that the meshing of the roller gears 18 and 19 can be set to the central control gear 5 each independently.

The holding devices 12 and 13 of the two work rolls 2 and 3 are supported by a support means 6 and stored or anchored in this. The support means 6 comprises four columnar support members 6A to 6D arranged in a rectangular arrangement and mounted or fixed on a common floor panel 6E supported on the floor 50. In each of the support members 6A to 6D, an associated tie rod 7A to 7B is vertically arranged in the longitudinal direction of the respective support member which is fixed to the bottom of the support plate 6E and above by means of an associated lock nut, preferably a hydraulically operated lock nut (9B, 9C in FIG. 3 ) is biased. In this case, a slotted Unterlagringsegment is placed under the hydraulic nut when the hydraulic nut is in the released state and then pressed by applying the hydraulic pressure, the nut on the Unterlagsringsegment. Thereby, the support means forming the frame of the rolling machine can be set under a certain tension. This leads to a stiffening of the roll stand.

FIG. 10 and 11 show a further embodiment of a cross wedge rolling machine 1, in which unlike the embodiment according to FIG 1 to 3 a first drive 42 for the first work roll 2 and a second, independent of the first drive 42 drive 43 for the second work roll 3. Each drive 42 and 43 includes an associated permanent magnet motor 44 and 45 and a - not shown - gear, for example, one, in particular three-stage, gear transmission, for transmitting the torque of the motor to the associated work roll 2 and 3. The reduction ratio of each transmission, for example, be 1:35. In the illustrated embodiment according to FIG. 10 and 11 are the rotation axis C of the output shaft of the permanent magnet motor 44 of the first drive 42 and the rotation axis D of the output shaft of the permanent magnet motor 45 of the second drive 43 orthogonal to the axes of rotation A and B of the respective work rolls 2 and 3 directed and the motors accordingly laterally Roll stand arranged.

Each of the permanent magnet motors 44 and 45 is controlled electronically, in particular via a converter. As a result, the work rolls 2 and 3 can be driven either electronically synchronously or asynchronously.

LIST OF REFERENCE NUMBERS

1

rolling machine

2.3

Stripper

4

drive motor

5

timing gear

6

support means

6A to 6D

support element

6E

baseplate

7A to 7D

tie rods

8A to 8D

guide

9

worm

9B, 9C

locknut

10

workpiece

12

holder

12A, 12B

part

13

holder

13A, 13B

part

14, 15

admission

16

feather

18, 19

gear

20, 21

Tool

23

recess

24, 25

extension

30, 31

Tool

33

recess

42, 43

rotary drive

45

output shaft

46, 47

Rotary drive gear

50

ground

60

positioning

61, 62

positioning parts

A, B

axis of rotation

C, D

drive axle

G

gravitational force

M

central axis

P

positioning

R

axis of rotation

w

tool clearance

W

Platen Gap

Claims (7)

Rolling machine with a) at least two rotatable or rotating, can be fitted with tools or equipped rollers for forming a can be arranged between the rollers or arranged workpiece, b) each roller being associated with at least one drive for independently driving the rollers, c) wherein each drive comprises at least one permanent magnet motor, in particular a torque motor. A rolling machine according to claim 1, wherein each permanent magnet motor is accelerated or decelerated to the rated speed for operating the roller (s) within a maximum rotational angle interval of at most 3 ° or at most 2.2 ° or at most 1 ° or even at most 0.5 ° , Rolling machine according to claim 1 or claim 2, wherein the at least one or each permanent magnet motor has a nominal torque of between about 5,000 Nm and about 80,000 Nm or between about 35,000 Nm and about 60,000 Nm and / or at least one or each permanent magnet motor Rated speed between about 20 U / min and 800 U / min or between about 30 U / min and 500 U / min. Rolling machine according to one or more of claims 1 to 3, wherein at least one drive comprises a converter for supplying the motor with electrical energy. Rolling machine according to one or more of claims 1 to 4, comprising at least one position detecting means for detecting or determining the rotational position of at least one of the rollers. Rolling machine according to one or more of claims 1 to 5, which is designed as a profile cross rolling machine or cross wedge rolling machine and / or wherein the rollers have in cross-section wedge-shaped or triangular profile tools which increase along the circumference in their radial dimension in one direction and / or extend obliquely to the axis of rotation of the associated roller. Rolling machine, in particular according to one or more of the preceding claims, with a) at least two rotatable or rotating, can be fitted with tools or equipped rollers for forming a can be arranged between the rollers or arranged workpiece, b) each roller being associated with at least one drive for independently driving the rollers, c) wherein the rolling machine is designed as a cross wedge rolling machine and due to the speed controllable and reversible drive is also used as a stretching roll machine.

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