WO2005070580A1

WO2005070580A1 - Bending device comprising compensator rollers

Info

Publication number: WO2005070580A1
Application number: PCT/EP2005/000161
Authority: WO
Inventors: Walter E. SPÄTH
Original assignee: Palima W. Ludwig & Co.; Klingelnberg Ag
Priority date: 2004-01-24
Filing date: 2005-01-11
Publication date: 2005-08-04
Also published as: MXPA06008167A; RU2349405C2; US20080257004A1; DE102004003681A1; KR20060126791A; CA2553737A1; JP2007518570A; RU2006130468A; EP1706227A1; CN1909990A

Abstract

Disclosed is a device for bending open, half-open, and closed hollow profiled members (11'). Said bending device operates with a central roller (3) that rests against the inner surface of the bent profiled member, a milling roller (4) which leans on the outer surface of the bend, and a bending roller (11) located at the discharge end of the profiled member. Said bending roller (11) acts upon the outer surface of the bend, counter to the supporting effect of a support roller (5, 6) that rests against the outer surface of the bend at the feeding end. In order to allow also thin-walled, sensitive profiled members to be shaped, additional milling rollers (12, 13) that act upon the top and bottom sidewall of the profiled member are disposed on a plane extending perpendicular to the bending plane in relation to the opposite central rollers and milling rollers (3, 4).

Description

Bending device with pendulum roller

The invention relates to a bending device with pendulum rolling rollers according to the preamble of claim 1.

The invention discloses a new bending method, which is also referred to below as cold flow form bending.

When cold forming, when bending hollow profiles, in particular open and half-open profiles, there is the problem that the profile tends to bulge, buckle, undulate or break.

In DE 197 17 472 A1, a solution to this problem has been proposed in such a way that a four-roll bending machine is equipped with a mandrel shaft which is positioned in the interior of the profile in the bending zone. The bending machine consists of a center roller bearing on the inside of the curved profile, a rolling roller resting on the outside of the arch and a bending roller arranged on the outlet side of the profile, which acts on the outside of the arch, against the supporting action of one on the inlet side on the outside of the arch support roller.

It was found that with this known bending device a rolling effect of the horizontal sheet sides (sheet inside and outside) of the profile takes place, in such a way that the roll roller lying on the sheet outside thins out the profile in this area and that lying on the inside of the sheet The central roller absorbs the reaction forces, which can lead to an increase in the wall thickness in the area of the inside of the arch due to a compression effect of the curved profile.

Up to now, material changes in the thickness of the material wall of the profile to be bent in the area of the inside and outside of the arch have been accepted without these material changes being able to be controlled in a controlled manner. The associated stretching and compression forces on the inside and outside of the arch accordingly have a correspondingly negative influence on the shape of the profile and the material structure.

This means that the material flow from the outside of the arch to the inside of the arch, or in the direction of the outside and inside of the arch (transverse, longitudinal flow of the structure in the profile cross section) could not be influenced in a controlled manner. Therefore bulges and faults could take place in the walls.

When this profile is bent, there is accordingly a stretching area in the outer curve and a compression area in the inner curve.

Stretching and upsetting are events that result from the application of force to overcome the section modulus of a section to be bent; these forces cause a material flow in the section to be bent.

The stretching and upsetting flow is caused by large tensile and compressive forces in the outside and inside of a profile sheet production when the elastic limit is exceeded.

In conventional bending of profiles according to DE 197 17 472 A1, deformations in the profile cross-section occur in the border area of a bend, whereby according to the subject of DE 197 17 472 A1 influence has already been exerted on these deformations to the extent that the inner and outer walls of the Profiles was given a clean guide through a mandrel shaft positioned in the bending zone.

However, so-called micro or macro crack formation could occur in the side wall of the curved profile, or shear forces at the transitions between rolled and unground walls, which could result in separation of the material. The homogeneity of the structure was disturbed or even interrupted. The invention is therefore based on the object of developing a bending device of the type mentioned in such a way that an optimal shaping of a profile is achieved without disturbing the homogeneity of the structure while avoiding micro or macro crack formation in the side walls of the profile.

This is to achieve a clean and dimensionally correct cross-sectional shape of the curved profile and a clean surface.

To achieve the object, the invention is characterized by the technical teaching of the claim.

It is essential that in the plane perpendicular to the bending plane with respect to the mutually opposite middle and rolling rolls, so-called pendulum rolling rolls are arranged, which act on the upper and lower side walls of the profile.

With this technical teaching, a new kind of flow form bending is proposed, which induces a structure flow in the bending axis of a profile. This structure flow arises from the rolling process at the moment when the bending process is started, along with the introduction of the rolling effect.

In this way, stretching and compression forces are reduced to a minimum or completely eliminated, depending on the rolling force to be applied and the depth of penetration of the rolling rollers into the material.

The homogeneity of the material during the bending process is largely maintained or is even improved by the compression according to the invention of all walls (outside of the arch, inside of the arch, top side wall and bottom side wall).

The previously mentioned harmful influences in the cross-sectional structure in the bending axis can therefore no longer arise. The invention accordingly proposes further rollers which bear against the upper and lower side walls, which are referred to below as oscillating roller rollers. However, the invention is not restricted to the term "pendulum roller". In the simplest embodiment of the invention, these rolling rolls (with or without a contour) are arranged in a non-oscillating manner, but rather rigidly.

The invention is primarily concerned with the induced structure flow that runs from the outside of the profile to the inside of the profile and controls this flow by attaching upper and lower roller rollers to the upper and lower side walls so as to redirect the flow from the outside of the arch to the inside of the arch and initiate there.

In addition, the volume shift causes a longitudinal flow with the consequence of an elongation above the bending line.

If, for example, an open, semi-open or closed hollow profile is bent two-dimensionally, an arch-shaped profile that lies in the XY plane results after the bending process. It is defined by an outer side of the sheet and an inner side of the sheet, the so-called rolling roller being in contact with the outside of the sheet, while the so-called center roller is in contact with the inside of the sheet.

When such a curve is produced, the profile on the outside of the curve is lengthened by the dimension l + ΔI, while the length I remains on the inside of the curve. This applies in the event that the bending line is on the inside of the sheet. This means that the entire profile cross-section is rolled out from the inside of the bend.

As a result of the rolling effect of the roller on the outside of the sheet, the material is elongated, along with a controlled flow of material in length, so as to produce the outside of the sheet. In the following, for the sake of clarity, the two walls (which are usually assigned plane-parallel to each other) on which the roller roll and the center roller abut, referred to as "end walls". The walls extending perpendicularly thereto are referred to as "side walls".

The invention is now concerned with the material flows which arise in the end wall on the outside of the bow and which, according to the invention, are deflected via the novel pendulum rolling rollers, which act on the side walls, over the associated side walls up to the end wall on the inside of the bow.

According to the invention, upper and lower oscillating roller rolls are now arranged, each of which lies on the upper and lower side walls. These take that

Material flow from the inside and outside of the sheet and distribute it depending on the penetration depth and inclination of the pendulum roller in the entire

Contact surface of the upper and lower side wall.

Therefore, the previously described disadvantageous structural changes due to stretching, shearing and compressive forces no longer occur because a structural flow of the material, induced by the upper and lower oscillating roller rolls, takes place in the upper and lower side walls.

If, for example, the wall thicknesses of a profile to be bent are of equal strength, the cross-section can be laid so that the compression area on the inside of the profile arch is largely eliminated due to the corresponding cross-sectional changes based on the previously described and calculated material shifts on the profile wall. There are therefore no longer any compressive forces that can cause deformation. Such laying of the bending line is achieved by rolling out on the side walls. For this reason, this process is also known as roll bending.

In this roll bending, the upper and lower oscillating roller rolls are tapered in their axial position against the plane parallelism of the profile to be bent. A greater rolling depth is therefore achieved on the two upper and lower side walls on the outside of the sheet than is comparatively on the inside of the sheet.

The adjustment of the axial position of the two upper and lower spherical rollers is therefore such that the spherical rollers on the upper and lower side wall on the outside of the arch have a relative depth of penetration into the material, whereas this depth of penetration towards the inside of the arch can be set to 0.

This ensures that even the bending roll, which is in itself necessary, can be omitted and only by this adjustment of the two pendulum rolling rolls in cooperation with the horizontal rolling and center roll, an arcuate shaping of the profile already takes place. There is no longer any need for a further bending roller, which rests on the outside of the arc of the profile at an axial distance from the previously mentioned center and roller rollers and reshapes it.

Of course, the invention is not limited to the elimination of the bending roller. It can also be provided that the bending roller is still present and that the pendulum rolling rollers according to the invention which are provided here and which act on the upper and lower side walls of the profile are additionally present.

It is important in this version that the bending line is laid on the inside of the arch and this induces a structure flow from the outside of the arch towards the inside of the arch. This is achieved by means of differently adjustable axial longitudinal angles of the pendulum roller and their depth of penetration into the material to be formed.

With this roll bending, it is also important that the material shifts taking place on the inside and outside of the sheet are also taken into account. For this purpose it is envisaged that the the roll on the outside of the arc (roller roll) is fed plane-parallel (or with an inclined position) against the outside of the profile, while the roll (center roll) lying on the inside of the sheet is fed plane-parallel or with an inclined position against the inside of the curve.

Here, the depth of penetration of the roll (roller roll) lying on the outside of the sheet is taken up by the pendulum rolling rolls lying perpendicularly to it and acting on the side walls and diverted into the side walls and passed over the side walls to the inside of the sheet.

It is important that there is no gap or free space in the profile to be formed between the roller (roller roller) on the outside of the sheet (roller roller) and the pendulum roller roller that is vertically connected to it. These rollers should therefore, if possible, enclose the profile to be formed in a form-fitting manner in order to avoid evasion, bulging and the like in this gap area.

In order to achieve this effect, it is necessary from a mechanical engineering point of view to design the pendulum roller to be displaceable in its longitudinal axis, so that it follows the profile to be formed during the bending process.

Thus, only the wall volume ΔV of the front and side walls of the curved profile is shifted from the outside of the arch towards the inside of the arch with decreasing ΔV to an increase in length. This ensures that there is no longer any material accumulation on the inside of the bend, but that these material changes on the outside of the bend ΔVmax to the inside of the bend are converted into a corresponding increase in length with ΔVmin.

The invention is not limited to the fact that in the case of so-called roll bending, only the pendulum rollers resting on the side walls are conically set against one another. In a further embodiment, it can also be provided that, in the case of certain profile shapes and special wall thicknesses, the rolling and center rollers which bear against the inside and outside of the arch are designed to be commuting accordingly and can accordingly also be used against one another.

If you have different wall thicknesses in the profile to be bent during roll-out bending, it is advisable to adjust the depth of penetration into the profile of the rolling and center rollers, which rest against the inside and outside of the arch, to be inclined.

The so-called gravity bending is shown below as the second embodiment of the teaching according to the invention.

With this gravity bending, the bending line remains in the gravity line, i.e. H. approximately in the middle of the profile to be bent if it is a symmetrical profile.

It is important with this gravity bend that the upper and lower pendulum rolling rollers, which are in contact with the upper and lower side walls, can either be placed at an angle to one another, or that they have a double conical running surface.

Gravity bending describes a state of bending in which the profile is thinned and elongated beyond the neutral line, i.e. the line of gravity, by stretching and elongating the wall thickness beyond the line of gravity.

At the location of the gravity line, the wall thickness begins to increase with volume, which has been displaced from the gravity line to the outside of the arch.

In other words: 1. What decreases in volume on the outside increases in volume on the inside. 2. What increases in elongation on the outside decreases in elongation on the inside. This rule applies to a profile with a symmetrical cross-section and wall. This physical process also results in a, albeit minimal, reduction in settlement due to the inward shift of the line of gravity.

The line of gravity, i. H. the center of gravity shifts by the dimension X towards the inside of the arch; caused by the material volume shift.

The internal profile cross section is largely preserved by the mandrel shank tool.

This knowledge forms the basis for the volume calculation to determine the various roll penetration depths on the profile walls and the radii of a profile to be bent that can be adjusted in a controlled manner.

The pendulum rolling rollers are now adjusted in accordance with the physical displacement phenomena mentioned above and the volume changes in the end and side wall area calculated from this.

The thinning in the outer area of the arch, the thickening in the inner area of the arch and the conical side wall changes are now rolled out in a targeted manner with the dimensionally accurate setting of the pendulum roller.

The advantage of gravity bending is:

1. A highly ductile structure (i.e. no distortions, micro or macro cracks in the structure). 2. Clean outer and inner contour of the profile cross-section (i.e. no warping, bulges, corrugations in the profile wall).

3. High dimensional accuracy of the profile arch and the profile cross-section.

4. Better surface quality of the profile after bending.

5. Higher bending performance. 6. Bent parts bent in a single operation.

7. Freely selectable bending contour.

8. Smallest possible radii and curves are bent with a single bending tool. The upsetting forces result in an increase in the material from the bending center line of the profile towards the inside of the arch in the same size as the decrease in material on the outside of the arch.

The so-called upsetting roll bending is described in more detail as a third embodiment of the invention. Here again upper and lower pendulum rolling rollers are present, in connection with a bending roller arranged axially offset from the aforementioned rollers.

The bending line is moved to the outside of the arch and the conical material thickening of the side walls is deflected into the inner wall of the arch. The main upsetting forces arise on the inner wall of the arch by shortening the sheet processing.

The upsetting roll bending uses opposed, braked center and roll rolls, i. that is, the speed of the respective roll on the inside and outside of the profile is lower than the speed of the profile through the bending gap. In addition, so-called brake shoes are arranged on the inside and outside of the bend, which increase the resistance to the profile to be bent and thus create a strong compression effect in the bending axis.

In general, all three bending processes are based on the knowledge that a symmetrical or asymmetrical volume shift of a profile cross-section by rolling out with pendulum rolling pollen, which abuts the upper and lower side walls, prevents a disruption of the structure.

The internal geometry (this is the internal cross-sectional shape) of a profile remains unchanged in terms of dimensions. It is important that the internal dimensions of the profile are maintained and only the external dimensions of the profile are changed in the sense of a volume shift. The inside dimension of the profile remains constant.

Alternatively, it is described below as a further possibility that the external profile dimension remains constant. This is achieved by means of a flexible, adjustable mandrel shaft, which absorbs the changes in wall thickness that occur inside the profile. From the outside you can therefore not see the curved profile that it has differently rolled wall thicknesses in the curved interior.

The bending line is the line on which the forces for stretching and upsetting build up and deform the corresponding profile.

It is important for the invention in all embodiments that the present invention is not only directed to a two-dimensional shaping of a profile, but that it can additionally be achieved with the arrangement of either contoured or oscillating rolling rollers that a helix (in three-dimensional shape) can be bent. In the case of spiral bending, even the bending roller and also the other known additional devices can be dispensed with, because this spiral shape is achieved solely by the volume shift (due to the pendulum rolling rollers).

This is achieved by conically positioning the center roller and the opposite roller.

The upper and lower pendulum roller rolls are still used for this purpose for the desired structural flow and for the radius of the bend.

The subject matter of the present invention results not only from the subject matter of the individual patent claims, but also from the combination of the individual patent claims with one another. All of the information and features disclosed in the documents, including the summary, in particular the spatial configuration shown in the drawings, are claimed to be essential to the invention, insofar as they are new to the prior art, individually or in combination.

In the following, the invention will be explained in more detail with reference to drawings showing several possible embodiments. Further features and advantages of the invention which are essential to the invention emerge from the drawings and their description.

Show it:

1: schematically shows the bending of a two-dimensional profile;

FIG. 2: the deformation of a profile during the bending according to FIG. 1 if there is no mandrel shaft carried in the bending zone;

3: schematically shows a top view of a bending device in a first embodiment;

Fig. 4: Section along the line A-A in Figure 3;

5: the enlarged representation of the profile to be bent under the influence of the rollers during gravity bending;

Fig. 6: the enlarged view of the profile to be bent under the influence of the various rollers during roll bending;

7: a second embodiment of a bending device in plan view;

Fig. 8: section along the line A-A in Figure 7;

9: Section along the line BB in Figure 7; 10: an enlarged representation of a profile to be bent during upsetting rolling bending with a device according to FIGS. 7 to 9.

Fig. 11: Section through the bending roll zone of the profile with the four adjacent rolls

Fig. 12: Schematic representation of the forming processes in section

In Figure 1, a symmetrical hollow profile (referred to as profile 1) is formed into a bent profile by symmetrical bending.

For the sake of simplification, it is not shown that additional support rollers 5, 6 according to FIG. 3 are arranged on the inlet side of the profile 1.

When comparing FIG. 1 with FIG. 3, it is important that a roller roll 4 rests on the outside of the sheet (outer end wall), while a middle roll 3 rests on the inside of the sheet (inner end wall). The two rollers are either both or only one of the two is driven in rotation.

In the interior of the hollow profile runs a mandrel rod 7, at the front end of which a mandrel shaft 8 is arranged, which has corresponding support elements 9, 10.

These support elements 9, 10 are highly wear-resistant support bodies which rest on the inside of the profile 1 in the region of the bending zone.

The bending zone is formed by the juxtaposition of the central rollers 3 and 4.

The profile can also be pushed through the bending zone in the direction of arrow 2 with a pushing device, not shown. FIG. 1 shows that the roller 4 rests on the outside of the sheet 53, while the middle roll 3 rests on the inside 52 of the sheet. It is thereby achieved that, for example, the inside of the arc is bent with a bending radius 15, while the outside of the arc 53 is bent with a bending radius 14.

In order to enable the bending at all, a bending roller 11 is arranged on the outside of the arch 53 at an axial distance from the bending zone, which can be moved into the position 11 'as shown so as to act with an adjustable force on the outside of the arch 53 of the profile to be bent ,

The bending roller 11 acts in principle against the resistance of the support rollers 5, 6, in particular the support roller 6, while the support roller 5 has only management tasks.

According to the invention, it is now provided that an upper pendulum roller 12 bears in a shaping manner on the upper side wall 50, while a lower pendulum roller 13 bears in a shaping manner on the lower side wall 51.

This is new and was previously described in the prior art.

The arrangement of the upper and lower oscillating roller rolls 12, 13 is also shown schematically in FIG. 1.

According to the invention, it is now provided in a first embodiment that these two oscillating rolling rollers 12, 13 are designed to oscillate in their axial position (with respect to the horizontal axis 21), i. H. the upper pendulum roller 12 can be pivoted in the arrow direction 18 on the pivot axis 22a and the lower pendulum roller 13 can be pivoted in the arrow direction 19 on the lower pivot axis 22b.

This makes it clear that the two pendulum rolling rollers 12, 13 are conically placed against each other and have a greater depth of penetration into the respective side wall 50, 51 on the outside of the sheet 53 than comparatively on the side wall 50, 51 in the direction of the inner side 52 of the arch.

Rather, it is provided in a preferred embodiment that the depth of penetration on the outside of the sheet 53 is at a maximum, while it runs towards 0 on the inside of the sheet 52.

In a development of the invention, it is provided that not only the pendulum rolling rollers 12, 13, which are assigned to the upper and lower side walls 50, 51, are designed to be pivotable and bevelled, but also that the rolling roller 4 and / or the central roller are also additionally provided 3 are also designed to be pivotable. Such pivoting can take place in the direction of the arrows 16, 17.

In the exemplary embodiment according to FIGS. 1 and 4, the upper pendulum roller 12 is pivoted clockwise in the direction of arrow 18 against the upper side wall d 50, while the lower pendulum roller 13 is pivoted counterclockwise (arrow direction 19) against the corresponding side wall 51.

FIG. 2 now shows that if the profile is reshaped when the corresponding guide means are removed, the profile 1 ′, which is undesirably deformed, results from a profile 1, which undergoes a corresponding indentation on the outside 53 of the arch with a corresponding reduction in the width dimension, whereby a simultaneous thinning of the material takes place.

An increase in material can be visualized on the inside of the arch 52, this increase being distributed in a corresponding dent and thickening of the wall thickness.

This phenomenon occurs especially when no mandrel shaft 8 is carried in the interior of the profile and stretching forces outside and compression forces inside deform the profile in the form shown. According to the invention, it is now provided according to FIG. 4 that the pendulum rolling rollers 12, 13 abutting the side walls 50, 51 are each guided with the rolling force F ₂ and F ₃ against the side wall 50, 51 and are simultaneously pivoted in the direction of the arrow 18, 19.

In the case of roll bending, a conical side wall profile of the curved profile 1 'thus results, as is shown in FIG. 4.

There is a thickening of the profile cross section in the area of the center roll 3 on the inside of the sheet, while in the area of the outside of the sheet there is a thinning of the profile. The material is distributed conically in the side wall area of the side walls 50, 51.

FIG. 5 shows the profile deformation on an enlarged scale during gravity bending.

The respective rollers 3, 4, 12, 13 are only shown in a hint, and only in the area of their running surfaces when they act on the respective outer sides of the profile 1 to be formed.

The transfer of the drawing figure 5 to the drawing figure 1 means that practically from the drawing plane of FIG. 5 the profile is bent upwards in the direction of arrow 26.

It is important here that the roller 4 is fed into the outer sheet 29 in the direction of arrow 46 (feed direction). The bending axis 54 runs through the zero line 30.

The previous, undeformed outer arch 29 transforms into the deformed outer arch 29 '. This is connected to a material thinning 43. The

Material thinning 43 results from the difference between the undeformed outer arch 29 and that which results after the bending Outer arch 29 '. The stretching forces that arise during the forming process result in said material thinning 43.

In the area of the side walls, where the corresponding pendulum rolling rollers 12, 13 act, there is a conical material thinning 31, as shown as thin, wedge-shaped surfaces 31, which extend perpendicularly from the vertical material thinning 43 on the outside of the sheet towards the inside of the sheet.

This wedge-shaped material thinning 31 disappears on the bending axis 54 in the region of the zero line 30.

Beyond the bend line 30 in the direction of the inner bend 28, there is again an increase in material 32 which, starting from the bend line 30 as a narrow, wedge-shaped wedge, increases in the direction of the inner side 52 of the bend.

This results in the same volume change between the material thinning 31 and the material increase 32.

It is now important that the respective pendulum rolling rollers 12, 13 have a specially contoured running surface and that they cannot be delivered to the respective side walls in a pendulum or beveled manner.

The tread 25 of the respective pendulum roller 12, 13 is chamfered in such a way that the tread part 25a rises conically from the bending line 30 to the outer curve 29. A maximum penetration depth of the pendulum rolling rollers 12, 13 acting in the outer curve is thus achieved. This depth of penetration supports arch elongation, i.e. H. the increase in length on the outside 53.

On the other hand, running from the bending line 30 to the right, in the direction of the inner side 52 of the sheet or the inner sheet 28, the running surface 25b of the respective oscillating roller 12, 13 is of exactly cylindrical design. This leads to the material increase 32 occurring in the side wall region 50, 51 in a conical shape in FIG Direction of arrow 33 is deflected into the inner arc 28. This takes place in that the respective pendulum rolling rollers 12, 13 are symmetrically and not beveled against the respective side wall 50, 51, as a result of which the increase in material 32 in the arrow direction 33 is displaced into the inner arch 28 and assumes the later inner arch shape 28 ′ there.

Therefore, there is an increase in material 32 'on the inside 52 of the sheet, so that the thinning dimension 36 on the left of the roller 4 is shifted to the right via the pendulum rollers 12, 13 towards the inside of the sheet, namely on the line of increase 32'.

Due to the conical material increases of the material increases 32, a material thickening 34 is created in the area of the inner wall of the inner arch 28.

The center roll 3 has only a shaping character in such a way that the profile of the inside 52 of the arch is only supported accordingly.

The resulting increase in material 44 results from the volume shift from the two wedges of the increase in material 32 occurring in the side wall.

The forces generated by stretching and compressing are the same, but with different signs. This is symbolized by the bevel, which means that the forces in the area of the central axis 23 and the bending axis 54 are at 0, while they are indicated with a minus in the area of the outer curve 29.

Decreasing means that they are indicated with a plus on the inner arch 28 and are therefore maximum.

A stretching force therefore arises on the outside of the arch, while a compression force arises on the inside of the arch. The thinning 27a that arises on the outer arch 29 is consequently converted into the same size in the compression thickness 27 on the inner arch 28.

With 35 the lateral limitation of the running surface 35 of the pendulum roller is described, which is shifted with the movement of the rolling roller in the direction of the running surface 35 '.

An arrangement for roll bending is described in FIG.

In this arrangement, it is essential that the pendulum rolling rollers 12, 13 do not have a specially contoured running surface 25, but that the pendulum rolling rollers 12, 13 are chamfered by an angle 45 (angle α) overall, namely from the outer curve 29 in the direction of the inner arch 28.

The bending line now shifts from the center of gravity in the central axis 23 in the direction of the bending line 30 to the inner arch 28.

It is important in the case of roll bending that a bending roller 11 is not absolutely required, but that the shaping bending is carried out only by the conical adjustment of the oscillating roller rollers 12, 13 with the aid of the feed of the roller roller 4 and center roller 3.

In this case, the center roll 4 is advanced in the direction of the arrow 46 (infeed direction) against the outer sheet 29, which results in a thinning of the material 43 and this thinning 43 is converted into an increase in length on the outer sheet 29.

At the same time, the material thinning 43 in the area of the side walls is converted into a wedge-shaped material thinning 31, which runs out towards the inside of the arch 28 on the inner arch 28. In the case of this roll-out bend, the bending line 30 is located on the inner side of the inner bend 28.

It is important here that the two pendulum rolling rollers 12, 13 are chamfered against each other in the direction of the arrows 18, 19, the depth of penetration on the left corresponding to the profile of the material thinning 43. All three rollouts, namely the rollout with the roller 4 and the oscillating roller 12, 13, take place at the same time.

For this reason, there is an increase in material 56 on the inside of the sheet.

The surface pressure of the roller 4 on the outer sheet 29 is approximately three times higher than the surface pressure of the center roll 3 resting on the inner sheet 28. This results in a penetration depth of z. B. 4 mm in the area of the outer sheet 29 and to a penetration depth of 1, 3 mm in the area of the inner sheet 28 for the corresponding rollers 4th, 3rd

The embodiment according to FIG. 6 is thus characterized in that the upper pendulum roller 12 is tapered relative to the lower pendulum roller 13, so that a greater depth of penetration of these two pendulum rollers 12, 13 takes place on the outer bow 29 than on the inner bow 28.

The penetration depth is 0 on the inner bend 28, where the bend line 30 runs.

The entire bending process takes place in the bending axis 54. In all three exemplary embodiments, it is essential, moreover, that the interior of the profile 1, 1 ′ in this bending axis 54 is always stabilized by the mandrel shaft 8 held there in a precise position, so that the internal dimension of the profile 1 is always achieved maintain stable. The action force of the roller 4 is consequently transmitted to the central roller via the profile and the mandrel shaft 8 held in the interior of the profile. Likewise, according to the invention, the pendulum rolling rollers 12, 13 are fed against the corresponding side walls 50, 51 of the profile with an adjustable feed force, this feed force being in the range of 100 kN.

The feed force of the roller 4 on the outer sheet 29 could be in the range of 400 kN, while the center roller 3 only experiences a reaction force. The center roll 3 takes up a total of 800 kN.

This is due to the fact that the roller 4 applies 4,400 kN, the bending roller 11, not shown, applies 200 kN to the profile, and this creates a reaction force on the support roller 5, 6. Furthermore, corresponding action forces of 100 kN each arise on the pendulum roller rolls 12, 13, so that the center roll takes up a total of 3,800 kN, the action forces of the pendulum roll rolls 12, 13 having no influence on the center roll 3.

FIG. 7 shows a second exemplary embodiment of a pendulum roller roll bending machine, which describes the upsetting roll bending.

The same device is used here as has already been explained with reference to FIG. 3. The explanations given there therefore also apply to FIG. 7.

However, FIG. 7 additionally shows that a link chain 39 is arranged at the front free end of the mandrel shaft 8, which links individual roller elements 40 to one another in an articulated manner.

This ensures that the roller elements 40 are arranged in the region of the bending axis 54 and in the outlet direction behind the bending axis 54 in order to additionally support the inner cross section of the profile V. A strong compressive force arises from the fact that the profile is pushed into the bending zone in the direction of arrow 2 and the speed at which the central roller 3 and the roller roller 4 drive the profile 1 is lower than the pushing speed in the direction of the arrow 2 one Squeezing effect on profile 1, which is additionally supported by two opposing brake shoes 37, 38.

The brake shoe 37 bears against the outside of the bow 53, while the brake shoe 38 bears against the inside of the bow 52.

FIG. 8 further shows that not only are the pendulum rolling rollers 12, 13 designed to be pivotable, but that it is also possible to also design the center roller 3 and the roller 4 to be pivotable. The latter rollers 3, 4 are then designed to be pivotable when not only a two-dimensional bending of the profile 1 is required, but when this profile is to be bent in a helical shape. This is symbolized by the arrow directions in FIG. 8.

FIG. 9 shows a section in the direction of line B-B in FIG. 7, where it can be seen that the brake shoe 38 is applied to the inside of the bow 52 to increase friction and thereby achieve a strong compression effect.

In the manner described above, the upper pendulum roller 12 bears against the upper side wall 50, while the lower pendulum roller 13 bears against the lower side wall 51, as shown in FIG.

It is characteristic of this exemplary embodiment that the bending line 30 is now laid on the outer curve 29. Here, the bending line 30 is understood such that no force acts on the profile 1 in this area. Accordingly, it is a neutral line.

From this bending line 30 on the outer bend 29, the compression onto the side walls 50, 51 in the direction of the inner bend 28 now begins, a conical increase in material 32 occurring in the region of these side walls. The pendulum rolling rollers 12, 13 have a straight, cylindrical running surface and are aligned plane-parallel to the original, unbent profile 1. During the bending, the wedge-shaped material increase 32 occurs and, at the same moment, this excess material 32 is deflected into the area of the inside of the sheet 52 where the pendulum rolling rollers are kept unchanged, where there is an additional increase in material 48 on the inner sheet 28.

The previously undeformed inner arch 28 is positioned radially outward in the direction of the inner arch 28 ', as shown in FIG. 10.

If the cone 32 were left in the area of the side walls 51, 52, then it would remain with the increase in material 48. However, if this material 32 is displaced from the side walls into the inner area of the arch, there is an additional increase in material 32 '.

If these two wedges of the material increase 32 are placed on top of one another in the region of the side walls 50, 51, this volume corresponds exactly to the volume of the material increase 32 'in the region of the inner curve 28'.

The tread 57 of the center roller has only a shaping character in order to form the enlarged inner arch 28 ".

The increase in material 48, 32 'on the inner arch 28 does not interfere with the use of such a profile.

Due to the violent shape and the rolling effect of the pendulum rolling rollers 12, 13, however, the conical material increase 32 in the side walls is displaced inward, so that the side walls 50, 51 of the deformed profile 1 maintain their absolute plane parallelism.

The development of a sheet is generally always measured from a bending line 30, which is on the outside of the sheet 29 in the exemplary embodiment shown. There is no material rolling effect on the outside of the sheet (outer sheet 29) and the material displacement phenomena are displaced into the inner sheet 28 via the side walls 15, 51.

Such upsetting roll bending is used when the statics of the bent profile make it necessary to keep the wall thickness of the outer curve 29 and the wall thickness of the side walls 50, 51 the same even after the forming. The increase in the wall thickness in the area of the inner arch 28 is harmless and increases the section modulus of the curved profile.

FIGS. 11 and 12 show an exemplary embodiment of roll bending with volume shift using the example of a square tube 200 x 200 x 20 mm:

Calculation of the volume shift:

Ua / 4 = Da x π / 4 = (200 x 3.14): 4 = 1,570 mm Ui / 4 = Di x π / 4 = (1600 x 3.14): 4 = 1,256 mm L = 314 mm

At 100% roll bending, the bending line lies on the inner curve, i.e. the development length does not change.

Fi = Ui x Si = 1256 x 20 = 25.120 mm 2

Sa = Fa / Ua = 25 120 mm ² / 1,570 mm = 16 mm wall thickness on the outside of the arch wall, ie 20 - 16 = 4 mm must be rolled out, the sum of the volumes remains constant, ie Fi = Fa.

The side walls are rolled symmetrically from the outside 4 mm inwards to 0. In the inverse ratio 200: 600 = 1/3 with a penetration depth from the outside of 4 mm, the penetration depth inside = 4/3 = 1.33 mm. This elongation on the inside is canceled out by the bending roller via upsetting. In this case, the penetration depth is denoted by 60 and the rolling depth by 61 in FIG. The amount of penetration depth on the inlet side is designated by 60, while the amount on the outlet side (opposite in sign) is designated by 60 '. The shift of the gravity line 58 to the further radially inward gravity line 58 'takes place in the form of a small step 59 in the bending roll zone.

drawing Legend

Profile 1 '

arrow

Central role

roller

supporting role

mandrel

spike shaft

support element

Bending roller 11 'upper pendulum roller lower pendulum roller

Bending radius outside

Bending radius inside

arrow

Central axis (roll)

Horizontal axis

Swivel axis 22a, 22b

Central axis (profile)

arrow

Tread 25a, 25b

arrow

Upset thickness 27a

Inner arch 28 ', 28 "

Outer arch 29 '

elastic line

material thinning Material increase 32 'arrow direction material thickening tread 35' thinning dimension brake shoe outside brake shoe inside link chain roller element profile thickening

Material thinning Material increase Angle α Infeed direction (left) Infeed direction (right) Material increase in arrow direction Side wall up Side wall down Inside arc Inside outside curve Axis line Material increase Tread gravity line 58 'Level penetration depth 60' Rolling depth

Claims

claims

1. Bending device for bending closed, semi-open and open hollow profiles with a center roller (3) lying on the inside of the bent profile (1, 1 '), a roller roller (4) lying on the outside of the arch and one on the outlet side of the profile arranged bending roller (11), which acts on the outside of the sheet, counter to the supporting action of a supporting roller (5, 6) lying on the inlet side on the outside of the sheet, characterized in that in the plane perpendicular to the bending plane with respect to the opposite center and roller rolls ( 3, 4) further rolling rollers (12, 13) are arranged which act on the upper and lower side walls (50, 51) of the profile.

2. Bending device according to claim 1, characterized in that the rolling rollers acting on the side walls (50, 51) are designed as oscillating rolling rollers (12, 13).

3. Bending device according to claim 1 or 2, characterized in that the material flows arising in the outside of the end wall are deflected via the pendulum rolling rollers (12, 13) acting on the side walls (50, 51) via the associated side walls into the inside end wall.

4. Bending device according to one of claims 1 to 3, characterized in that during roll bending, the upper and lower oscillating rolling rollers (12, 13) are conical in their axial position against the plane parallelism of the profile to be bent.

5. Bending device according to claim 4, characterized in that on the two upper and lower side walls (50, 51) on the outside of the sheet a greater rolling depth is achieved than comparatively on the inside of the sheet.

6. Bending device according to claim 4 or 5, characterized in that the pendulum rollers (12, 13) on the upper and lower side wall (50, 51) on the outside of the sheet have a relative depth of penetration into the material, whereas the depth of penetration towards the inside of the sheet expires to 0.

7. Bending device according to one of claims 4 to 6, characterized in that the bending line is laid on the inside of the arch and a structure flow is induced from the outside of the arch towards the inside of the arch.

8. Bending device according to one of claims 4 to 7, characterized in that the outer sheet-side roll (rolling roll) is fed plane-parallel against the outside of the profile sheet, and that the adjacent roller (center roll) is fed plane-parallel against the inside of the sheet.

9. Bending device according to one of claims 4 to 8, characterized in that the rolling and center rollers lying on the inside and outside of the sheet are designed to be oscillating and are set against one another.

10. Bending device according to one of claims 1 to 9, characterized in that when gravity bending of a symmetrical profile, the bending line remains in the line of gravity, approximately in the middle of the profile to be bent.

11. Bending device according to one of claims 1 to 10, characterized in that the upper and lower oscillating roller rolls (12, 13) have an at least partially conical running surface.

12. Bending device according to claim 11, characterized in that in the area on a central (middle) center line from the bending line to the outside the contour has a slope, and that from the bending line towards the inside of the curve, the contour of the upper and lower oscillating roller (12, 13) is plane-parallel to the profile shape of the original undeformed profile.

13. Bending device according to one of claims 1 to 12, characterized in that during upsetting rolling bending, the bending line is laid toward the outside of the sheet and the thickened material of the side walls are deflected into the inside wall of the sheet.

14. Bending device according to one of claims 1 to 13, characterized in that the speed of the respective roll on the inside and outside of the profile is lower than the speed of the profile through the bending gap.

15. Bending device according to one of claims 1 to 14, characterized in that brake shoes are arranged on the inside and outside of the bend, which increase the resistance to the profile to be bent and a strong compression effect occurs in the bending axis.

16. Bending device according to one of claims 1 to 15, characterized in that in addition to the pendulum rolling rollers (12, 13), the center roller (3) and the roller roller (4) are pivotable.

17. Bending device according to one of claims 1 to 16, characterized in that the center roller and the opposite roller roller are conically inclined.

18. The method with a device according to one or more of claims 1 to 17, characterized in that the material flows which arise in the end wall on the outside of the bend are deflected into the end wall on the inside of the bend via the associated side walls.

19. The method according to claim 18, characterized in that during flow form bending, a structural flow is induced in the bending axis of a profile, which runs from the outside of the profile of the profile towards the inside of the profile (roll bending).

20. The method according to claim 18, characterized in that during flow form bending, a structural flow is induced in the bending axis of a profile, which runs from the inside of the profile towards the outside of the sheet (upsetting roll bending).

21. The method according to claim 18, characterized in that the gravity line (= approximately bending line) remains unchanged when the flow form is bent, that due to the compression forces from the bending center line of the profile an increase in the material takes place in the direction of the inside of the bend and that in the same volume size one Material is removed by rolling out on the outside of the sheet (), with the result that the rolling effects eliminate crushing and stretching forces by rolling out (gravity bending).