CN117241901A

CN117241901A - Wire straightening machine and method for straightening wire or strip material

Info

Publication number: CN117241901A
Application number: CN202280031099.4A
Authority: CN
Inventors: A·穆伦费尔德; W·雷施
Original assignee: EVG Entwicklungs und Verwertungs GmbH
Current assignee: EVG Entwicklungs und Verwertungs GmbH
Priority date: 2021-04-27
Filing date: 2022-04-26
Publication date: 2023-12-15
Also published as: AT524979A1; EP4329959A1; WO2022229850A1; IL308038A; BR112023019770A2

Abstract

The invention relates to a method and a device for straightening wire/strip material by means of a trimming device, comprising correction rollers acting offset on opposite sides of the passing material (1), wherein the correction rollers are automatically positioned in dependence on a model determined by means of input data of the material in such a way that the linearity requirement is met, wherein the position of at least one correction roller is continuously adapted on the basis of data detected during the passing of the trimming device, said data representing the linearity achieved, wherein the deflection of the material in the Y-direction and in the Z-direction after passing through the arrangement of the correction rollers (3, 4, 6, 10) is measured by means of three sensors (13, 14, 15) arranged along the X-axis of the material, and the measured values obtained are input into the model controlling the positioning of the positionable correction rollers.

Description

Wire straightening machine and method for straightening wire or strip material

Technical Field

The invention relates to a method for straightening a wire or a strip by means of a trimming device, comprising correction rollers acting offset on opposite sides of a passing material, wherein, depending on a model determined by means of input data of the material, some of the correction rollers are automatically positioned such that the linearity requirement is met, wherein, on the basis of the data detected during the passing of the trimming device, the position of at least one correction roller is continuously adapted, the data representing the linearity achieved, wherein, within the model, an X axis is located in the passing direction of the material, and a Y axis and a Z axis are perpendicular to each other and to the X axis.

The invention further relates to a wire straightening machine or device for straightening wire or strip material, comprising a straightening device comprising two rows of non-driven straightening rollers arranged longitudinally offset relative to each other, which in operation act on the material passing between the rows in order to straighten the material, wherein some of the straightening rollers can be positioned onto the material in an automatically controlled manner depending on a mould in which an X-axis is located in the direction of passage of the material and a Y-axis and a Z-axis are perpendicular to each other and relative to the X-axis in such a way that the linearity requirements of the material discharged from the straightening device are fulfilled.

Background

WO 2020/172694 teaches a method and an apparatus wherein a wire can be straightened straight in an adaptable straightening device. For this purpose, the temperature of the wire, the force on the straightening rollers or the deflection of the straightened free wire is measured continuously after leaving the straightening device, which is fed into the mould and used to adapt the positioning of some of the straightening rollers on the wire. Disadvantageously, in the case of the measurement of wire deflection, free wires must be present, which cannot be directly processed further in an automated manner.

WO 2015/144539 A1 discloses a method in which the relation between the force acting on the correction roller and the "correction product properties", for example the flatness of the correction product, is mainly determined within test measurements. A model is then formed which allows the positioning of the correction rollers to be adapted to the characteristics of the correction product being run during the correction process, without measuring forces. Disadvantageously, the method only occurs in the range of the test measurement.

Disclosure of Invention

The object of the present invention is to provide a closed control loop for an autonomous method for straightening an unknown correcting product with a curvature change, wherein the wire ends are not free, wherein the straightening machine is not particularly long compared to conventional machines, and wherein no separate test measuring runs have to be carried out.

In the method described at the outset, the deviations of the material in the Y-direction and in the Z-direction after passing through the arrangement of the correction rollers are measured by means of three sensors arranged along the X-axis of the material, and the measured values obtained are fed into a model which controls the positioning of the positionable correction rollers.

In one embodiment of the method, the trimming devices are successively traversed by the wire or strip material, one trimming device having a horizontally disposed leveling roller and the other trimming device having a vertically disposed leveling roller.

In a further advantageous alternative, the material is cut to a predetermined length behind the third sensor, seen in the direction of penetration.

The position of the material is measured behind all correction rollers, seen in the direction of passage, by measuring the deviation of the material from the axis of passage (X axis) in the direction of positioning of the correction rollers (Y axis) and perpendicular to the two axes (Z axis). For this purpose, known optical measuring methods are considered, for example, by means of laser distance sensors (so-called laser scanners) or ultrasonic sensors. It is conceivable that the position measurement is carried out only at the beginning of the method for calibration purposes, while in continuous operation the measurement of the forces acting on the correction rollers is sufficient for carrying out the method according to the invention.

The invention further relates to a device for carrying out the method according to the invention. The invention also consists in such a device in that three sensors for measuring the deflection of the material in the Z-direction and in the Y-direction, which are spaced apart from one another in the X-direction, are arranged behind the dressing device, as seen in the direction of movement of the material, wherein all the measured values obtained can be fed to a model which controls the positioning of the positionable correction rollers.

In an alternative embodiment of the invention, a wire cutter is arranged behind the third sensor, as seen in the direction of penetration.

In a further embodiment, the two trimming devices are passed successively through the wire, one trimming device having a horizontally disposed leveling roller and the other trimming device having a vertically disposed leveling roller.

In the alternative, it is also conceivable to provide a second trimming device, which comprises two rows of non-driven correction rollers arranged opposite each other in a longitudinally offset manner, which in operation act on the material passing between the rows, after the third sensor, wherein the second trimming device acts on the material offset by 90 ° relative to the first trimming device.

Drawings

The invention is further explained with the aid of the figures, wherein fig. 1 shows a trimming device, comprising a wire running through it, fig. 2 shows the same trimming device, comprising the indicated measuring points, fig. 3 shows a graphical model of the wire deflection and fig. 4 shows a regulating circuit as a block diagram.

Detailed Description

The finishing assembly according to fig. 1, which belongs to the prior art, has two rows of horizontal correcting rollers 3, 4, 6, 10 which are arranged horizontally offset with respect to one another. One row acts on the wire material 1 to be straightened below and the other row acts on the wire to be straightened above. The wire material 1 to be straightened may also be a strip material (not shown); the wire or ribbon material is then represented by the expression wire material. The correction rollers 3, 4, 6, 10 have no rotary drive, which is penetrated by a wire as the material 1, which is moved in the direction of arrow 2 by a feed roller, not shown. The wire is typically passed successively through two trimming devices each offset by 90 ° from each other, one having a horizontal leveling roller and the other having a vertical leveling roller. The primary working area of the present invention has a wire diameter of between about 4mm and about 20 mm.

The two first correction rollers 3 of the lower row in fig. 1 have a fixed rotation axis. The lower leveling roller 4 adjoining the first leveling roller can be positioned on its own on the passing material 1 by means of an adjusting device indicated with 5. The three first straightening rollers 6 of the upper row can be positioned jointly on the material 1 and for this purpose are supported on a common support 7, which can be adjusted in height by means of a lever 8 by means of an adjustment motor 9. The upper leveling roller 10 on the adjacent upper leveling roller 6 can be positioned on the material itself by means of an adjusting device indicated by 11.

Fig. 2 shows diagrammatically that three sensors 13, 14, 15 are installed in the correction device after the correction rollers 3, 4, 6, 10, which sensors determine the position of the corrected wire in the Y-direction and in the Z-direction (not plotted, since perpendicular to the paper plane). The magnitude and direction of the curvature that is also present is determined by the three sensors 13, 14, 15 that are spaced apart from each other in the X-direction. Fig. 3 shows the model for this purpose, wherein the curvature b relates to a predetermined length l. l is a path section along the X-axis, which starts after the correction roller of the finishing device. The path section may also be located between two trimming devices that are offset or rotated by 90 °. Ideally, all three sensors 13, 14, 15 are located in the path section 1.

When the wire has a curvature in the cut state (e.g. according to fig. 3b/l >2 mm/m), this is already visible in the clamped state of the material 1 before the shears 16 or other elements of the straightening machine. Although the curvature does not appear exactly as well in the clamped state after being sheared by the scissors 16. But already seen on the wire material 1 visible after the first trimming means of the (perhaps two) trimming means, the presence or absence of curvature. It can even be seen if there is a strong curvature.

However, the relationship is non-linear and also not directly proportional, as the wire works against the clamped state and can deflect in all directions. It is therefore the prevailing opinion in the prior art that the curvature of a wire can be determined with sufficient accuracy only when the wire ends are free.

It is unexpected that characteristics of the wire rod having curvature in a state of being clamped on both ends can be modeled. In the method to be used for this purpose, the curvature of the wire material 1 in the Y-direction and Z-direction is determined from three position measurements. The curvature b from fig. 3 becomes a vector in three-dimensional space. The vector is entered into a non-linear model from which a prediction of the actual curvature is calculated, which curvature is to be compensated by the new positioning of the correction rollers 3, 4, 6, 10. The study has been directed to a non-linear model by which the difference between the actual curvature and the predictions in the range of the mean value of the curvature of the straight wire is sufficiently small, i.e. the predictions are sufficiently accurate to identify deviations from the desired corrective result.

By means of curvature prediction, a state estimation in the predicted control loop is achieved according to fig. 4. The adjustment itself takes place by means of a model which maps the deviations in the correction result to the required adjustment corrections of the correction unit.

Claims

1. Method for straightening wire or strip material by means of a finishing device comprising correction rollers acting offset on opposite sides of a passing material (1), some of which correction rollers are automatically positioned in dependence on a model determined by means of input data of the material (1) such that the requirement for linearity is fulfilled, wherein the position of at least one correction roller is continuously adapted based on the data detected while passing the finishing device, which data represent the linearity achieved, wherein within the model the X-axis is located in the passing direction of the material (1) and the Y-axis and Z-axis are perpendicular to each other and to the X-axis, characterized in that the deflection of the material (1) in the Y-direction and Z-direction after passing the arrangement of the correction rollers (3, 4, 6, 10) is measured by means of three sensors (13, 14, 15) arranged along the X-axis of the material (1), and the obtained measured values are input into the model controlling the positioning of the positionable correction rollers (6, 4, 10).

2. A method according to claim 1, characterized in that two trimming devices are passed successively by the wire or strip, wherein one trimming device has a horizontally arranged straightening roll (3, 4, 6, 10) and the other trimming device has a vertically arranged straightening roll.

3. A method according to claim 1 or 2, characterized in that the material (1) is cut to a predetermined length after the third sensor (15) seen in the direction of passage.

4. Apparatus for carrying out the method for straightening wire or strip material according to one of claims 1 to 3, comprising a trimming device comprising two rows of non-driven straightening rollers (3, 4, 6, 10) which are arranged offset relative to one another in the longitudinal direction and which in operation act on a material (1) passing between the rows in order to straighten the material, wherein some of the straightening rollers (6, 4, 10) can be positioned onto the material (1) in an automatically controlled manner in dependence on a model in which an X-axis is located in the direction of passage of the material (1) and a Y-axis and Z-axis is perpendicular relative to the X-axis, characterized in that three sensors (13, 14, 15) for measuring the deflection of the material (1) in the X-direction and Y-direction are arranged behind the trimming device, seen in the direction of movement of the material, wherein all obtained measured values which can be fed to the model (6, 10) which can be positioned are provided.

5. The device according to claim 4, characterized in that a wire cutter (16) is arranged behind the third sensor (15) as seen in the direction of penetration.

6. An apparatus according to claim 4 or 5, characterized in that two trimming devices are passed successively by the wire (1), wherein one trimming device has a horizontally arranged straightening roll (3, 4, 6, 10) and the other trimming device has a vertically arranged straightening roll.