EP2952268B1 - Bending machine and bending method - Google Patents

Description

The invention relates to a bending machine and method for bending round material.

Bending machines of this type are generally used for bending round material, which may be formed in particular as a pipe material. Furthermore, solid material can also be processed with these bending machines. Generally, such bending machines include a bending head by means of which the round material can be bent. The bending head is arranged stationary. The round material to be bent is mounted on a workpiece holder, which is in particular a chuck. The chuck is moved to perform a bending operation so that the round material mounted thereon is brought into a desired position on the bending head, so that then the bending head can perform a bending operation.

In bending machines of modern design, the aforementioned steps are automated. The assembly of the chuck with round material can be done by a robot standing or driving on the floor of a factory floor, so as to fix the respective round material to be machined on the chuck. Then the chuck is also automatically moved to supply the round material to the bending head. Since the bending head and the chuck are arranged with the Zustellmittel also on the floor of the factory, the supply of the round material takes place in the horizontal direction. Adapted to the round material is arranged in the horizontal direction on the chuck.

Such bending machines work flawlessly and with high precision, as long as the round materials to be bent form relatively short parts.

Often, however, it is necessary to work with such bending machines and long parts. Examples of this are pipelines that are installed in motor vehicles, in which cables can be performed in these pipes or gaseous or liquid media are transported in these pipelines. Such pipelines are to be adapted to the conditions specified in the motor vehicle. As a result, pipelines with lengths in the meter range are required there, which have to be bent several times, possibly in different planes, and thus run along a complex three-dimensional path.

The production of such complex bent parts, in particular piping, is insufficiently feasible with known bending machines. Since the round material to be bent on the chuck is mounted to extend in a horizontal direction and the weight of the round material is considerable due to its length, this is deformed during storage on the chuck by this large weight, so that the bending process to be performed is correspondingly unreproducible and inaccurate. This effect is exacerbated by the fact that when performing several bending operations and the resulting complex geometries of the round material this begins to vibrate strong and uncontrolled during transport with the chuck.

In principle, these effects can be partially reduced if a robot, in addition to supporting the round material on the chuck, holds and supports this round material in the area of the free end. However, since the round material is bent in a short time sequence and thus changes the orientation of the round material in space quickly and drastically, a tracking of a robot is possible only with disproportionate effort.

The DE 41 24 356 C1 relates to a bending machine for long, thin strands, especially pipes. In this bending machine, the base frame is designed as a support column pivotable about a vertical axis, which has a horizontal cantilever at its upper end. A rotatably drivable clamping head is rotatably mounted at the free end of the cantilever arm about a vertically arranged main axis. A bending head carriage with a bending head is vertically displaceable below the cantilever on the support column. The support column is pivotable with the cantilever from a loading position, in which the chuck is in the vicinity of a magazine, about the vertical axis in a bending position remote from the magazine and optionally in an unloading position. The arranged outside the pivoting range of the cantilever magazine is designed as a hanging magazine, in which the strands are each held at its upper end and arranged vertically hanging. By means of a loading device, the strands can be removed individually from the hanging magazine and brought to the main axis.

The invention is based on the object, a bending machine and a method of the type mentioned in such a way that even round material can be processed efficiently and precisely with large lengths with low design effort.

To solve this problem, the features of the independent claims are provided. Advantageous embodiments and expedient developments of the invention are described in the subclaims.

The invention relates to a bending machine for bending round material according to claim 1. Furthermore, the invention relates to a corresponding method.

With the bending machine according to the invention or with the method according to the invention, even very long round materials can be processed in a surprisingly simple manner quickly and with high precision.

The basic idea of the invention consists in supporting the round material to be processed hanging on the workpiece holder, which is preferably formed by a chuck. In this case, the workpiece holder forms a stationary unit in the bending operation to be carried out in each case, while the bending head forms a unit movable with respect to the workpiece holder, the process affecting vibrations of the round material are minimized at the Werkstückaufhahme.

An essential aspect of the invention is further that the workpiece holder holds the round material at the upper end and the round material stored so hanging down. This avoids unwanted deformation of the round material during storage on the workpiece holder solely by utilizing gravity. Since, because of the hanging support of the round material whose center of gravity is below the workpiece holder, only an extremely low torque is exerted on the round material by the weight of the round material. But this reduces the forces that lead to deformation of the round material minimized, whereby the precision of the bending operations to be performed is significantly increased.

The suspended storage of the round material is advantageously realized in that the linear drive forms a vertical arrangement, at the upper end of the workpiece holder is arranged so that is attached to this round material hanging down.

In this case, the linear drive on a line extending along a guide and a drive means, wherein the workpiece holder is firmly connected to the guide. By means of the drive means of the bending head along the guide for performing bending operations is movable.

In particular, before starting the processing of the round material, if this runs along a straight line, the workpiece holder and the center of gravity of the round material are exactly on a straight line extending in the vertical direction, that is, the center of gravity of the round material is exactly below the workpiece holder, so that in this case no torque acts on the round material, which would lead to its deformation.

When performing the bending operations, however, the round material is bent away laterally so that the center of gravity of the round material is still below the workpiece holder is, but now laterally offset to this. For round materials with long lengths in the meter range, this lateral offset can be significant, so that then by acting torques, the round material can be deformed.

To compensate for this effect, the entire linear drive can be tilted and / or pivoted with the workpiece holder arranged thereon as a whole unit.

Advantageously, the linear drive with the workpiece holder on a frame about a first axis of rotation is pivotable and / or arranged tiltable on a second axis of rotation.

As positioning according to the invention a positioning means is provided with a control unit. By means of the control unit, the pivoting and / or tilting movement of the linear drive is controlled so that the deviation of the center of gravity of the round material to be bent from a passing through the workpiece holder, extending in the vertical direction is minimal.

In this way, preferably after each bending operation by pivoting and / or tilting the arrangement of the linear drive with the workpiece holder, the position of the round material at its geometry changed by the bending process adapted so that the center of gravity of the round material is as accurately as possible below the workpiece holder. By this control, not only undesirable deformations of the round material are significantly reduced, but also vibrations of the round material, after this has been bent.

Thus, with the bending machine according to the invention also round materials can be accurately machined with long lengths, wherein the round materials can be formed as solid or tube materials.

In order to realize geometrically complex structures of the round material in the implementation of the bending process, it is advantageous if the bending head is designed to perform in several planes bending operations.

Figur 1:

Ausführungsbeispiel der erfindungsgemäßen Biegemaschine in einer Längsschnittdarstellung.

Figur 2:

Frontansicht der Biegemaschine gemäß Figur 1.

Figur 3:

Einzeldarstellung des Biegekopfs der Biegemaschine gemäß den Figuren 1 und 2.

Figur 4a, b:

Schematische Darstellung der Positionierung des Linearantriebs mit dem Spannfutter der Biegemaschine gemäß den Figuren 1 und 2 bei unterschiedlichen Bearbeitungsschritten zur Bearbeitung einer Rohrleitung.

The invention will be explained below with reference to the drawings. Show it:

FIG. 1:

Embodiment of the bending machine according to the invention in a longitudinal sectional view.

FIG. 2:

Front view of the bending machine according to FIG. 1 ,

FIG. 3:

Individual representation of the bending head of the bending machine according to the FIGS. 1 and 2 ,

FIG. 4a, b:

Schematic representation of the positioning of the linear drive with the chuck of the bending machine according to the FIGS. 1 and 2 at different processing steps for processing a pipeline.

The Figuren1 and 2 show an embodiment of the bending machine according to the invention 1. The bending machine 1 comprises a frame 2, with which the bending machine 1 is parked on a floor B of a factory floor or the like.

On the frame 2 a movable on a linear actuator 3 bending head 4 is mounted. The linear actuator 3 is in the in FIGS. 1 and 2 aligned arrangement in the vertical direction. The linear drive 3 comprises a guide 5 and a drive means in the form of a belt drive. The guide 5 consists in the present case of a metal carrier running along a straight line. The thus formed linear drive 3 is controlled by a control unit, not shown, which is preferably housed in a control cabinet, also not shown. The belt drive points a servo drive, not shown, which moves a belt 6, which is arranged along the guide 5. As a result, the bending head 4 is moved along the guide 5.

At the upper end of the guide 5, a workpiece holder in the form of a chuck 7 is provided. The chuck 7 is fixedly connected to the guide 5 and thus arranged stationary with respect to this. In the chuck 7 is in the FIGS. 1 and 2 not shown round material clamped with its upper end, so that it is mounted hanging on the chuck 7.

To carry out a bending operation, the bending head 4 is moved along the guide 5 by means of the linear drive 3 against the mounted on the chuck 7 round material.

The essential components of the bending head 4 are in FIG. 3 shown. The bending head 4 is designed for a multi-level machining of the round material. Correspondingly, the bending head 4 comprises a bending tower 8 and components assigned to it as a clamping jaw holder 9 and a counter holder 10. To carry out different bending operations, the clamping jaw holder 9 has a plurality of clamping jaws 9a-9d in different planes, which interact with the bending tower 8 and the counter holder 10.

The linear drive 3 with the movable bending head 4 and the chuck 7 can be pivoted and tilted as a complete unit with respect to the frame 2 during processing of the round material. In this case, the linear drive as in FIG. 2 are pivoted by an angle of ± 40 ° with respect to a pivot axis 12 extending to the right to the plane of the drawing, wherein the pivot axis in FIG. 1 denoted by 12. As in FIG. 1 illustrated, the linear drive 3 can be tilted during processing of the round material by up to 25 ° with respect to a plane perpendicular to the plane tilting axis 13, wherein the tilting axis is denoted by 13. For maintenance purposes, the linear drive 3 even by 90 ° tilted forward, so that the linear drive 3 is oriented in the horizontal direction and all components are easily accessible for maintenance.

For tilting and pivoting of the linear drive 3 this is fixed by means of a tilt and pivot bearing 11 on the frame 2. How out FIG. 1 it can be seen, the tilting and pivot bearing 11 has a first shaft for forming the pivot axis 12 and a second shaft for forming the pivot axis 13 oriented perpendicular to the pivot axis 12.

To carry out the tilting movement, a guide carriage runs along a horizontal direction through a servo drive, not shown.

The tilting and pivoting movement is given by a two-point bearing of the linear drive 3, which is formed on the one hand by the pivot axis 12 and the other by the element 14. By this two-point bearing a stable, vibration-free mounting of the linear drive 3 is obtained.

The pivoting movement about the pivot axis 12 is again via a servo drive, not shown. When pivoting the linear drive 3, the element 14 must perform corresponding compensating movements in the form of a rotary movement and a linear movement in a guide element 15. The guide element is arranged on an adjustable plate 16.

The tilting and pivoting movement of the linear drive 3 is controlled by the control unit during processing of the round material. The control is such that the center of gravity of the round material is as directly as possible under the chuck 7, so the storage of the upper end of the round material. This is achieved during the bending operations performed with the bending head 4 that the center of gravity of the round material is as directly as possible below the chuck 7. This, in turn, ensures that the suspension of the round material on the chuck 7 is stabilized in such a way as a result of gravity that as few oscillations as possible occur in the round material. In addition, torques acting on the round material due to the inherent weight of the round material are minimized, and thus also possible deformations of the round material, which would lead to impairment of the quality of the bending operations.

Such a tracking of the tilting and pivoting position of the linear drive 3 is shown schematically in the FIGS. 4a, 4b illustrated. The FIGS. 4a, 4b schematically show the linear drive 3 with the chuck arranged there 7. The chuck 7 is a round material in the form of a long pipe 17 is arranged.

FIG. 4a shows the arrangement at a first time after the pipe 17 has just been bent at a second location by about 90 °. Together with the first bending point results in a Z-shape of the pipe 17 so that it protrudes laterally far beyond the region of the linear drive 3, wherein in the arrangement of FIG. 4a the linear drive 3 is still in the vertical direction.

In the arrangement according to FIG. 4a Although the focus of the pipe 17 is still below the chuck 7 but laterally offset to this. Due to this, high torques act on the pipe 17, which can lead to deformation of the pipe 17. To avoid this, the linear actuator 3 is in the position according to FIG. 4b pivoted. In this position, the center of gravity of the pipe 17 is almost exactly below the chuck. 7

LIST OF REFERENCE NUMBERS

(1)

bending machine

(2)

frame

(3)

linear actuator

(4)

bending head

(5)

guide

(6)

belt

(7)

chuck

(8th)

bending tower

(9)

Jaw holder

(9a-9d)

jaws

(10)

backstop

(11)

pivot bearing

(12)

swivel axis

(13)

tilt axis

(14)

element

(15)

guide element

(16)

plate

(17)

pipeline

(B)

ground

Claims (8)

1. Bending machine (1) for bending round material, comprising a workpiece mount on which the round material is mounted, and a bending head (4) for carrying out bending processes of the round material, wherein the bending head (4) is movable by means of a linear drive (3) and the workpiece mount is arranged to be stationary with respect to the linear drive (3), wherein positioning means are provided by means of which the workpiece mount is so positionable that when the bending processes are carried out the centre of gravity of the round material mounted on the workpiece mount can lie below the workpiece mount, characterised in that the positioning means comprises a control unit by means of which the linear drive (3) is pivotable or tiltable together with the workpiece mount and wherein control of the pivoting and/or tilting movement of the linear drive (3) can take place in such a way by means of the control unit that the departure of the centre of gravity of the round material to be bent from a straight line passing through the workpiece mount and extending in vertical direction can be minimised.
2. Bending machine according to claim 1, characterised in that the linear drive (3) comprises a guide (5) extending along a straight line and a drive means, wherein the workpiece mount is fixedly connected with the guide (5) and wherein the bending head (4) is movable by way of the drive means along the guide (5) to carry out bending processes.
3. Bending machine according to claim 2, characterised in that the drive means is a belt drive.
4. Bending machine according to any one of claims 1 to 3, characterised in that the workpiece mount is a chuck (7).
5. Bending machine according to any one of claims 1 to 4, characterised in that the bending head (4) is constructed to carry out bending processes in a plurality of planes.
6. Bending machine according to any one of claims 1 to 5, characterised in that the linear drive (3) forms a vertical arrangement, at the upper end of which the workpiece mount is so arranged that round material is secured thereto to hang down.
7. Bending machine according to any one of claims 1 to 6, characterised in that the linear drive (3) together with the workpiece mount is arranged at a frame (2) to be pivotable about a first axis of rotation and/or tiltable at a second axis of rotation.
8. Method for bending round material by means a bending machine, in which the round material to be bent is mounted on a workpiece mount and bending processes for bending the round material are carried out by a bending head (4), wherein the workpiece mount is arranged in stationary positon at the linear drive (3) and the bending head (4) is moved towards the workpiece mount for carrying out bending processes, wherein positioning means are provided by way of which the workpiece mount is so positioned that when the bending processes are carried out the centre of gravity of the round material mounted on the workpiece mount lies below the workpiece mount, characterised in that the positioning means comprises a control unit by way of which the linear drive (3) is pivotable or tiltable together with the workpiece mount, and wherein control of the pivoting and/or tilting movement of the linear drive (3) is carried out by means of the control unit in such a way that the departure of the centre of gravity of the round material to be bent from a straight line passing through the workpiece mount and extending in vertical direction is minimal.

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