Machine for profile rolling with displaceable rollers . The invention relates to a profile rolling machine for bending of metal profiles.

Description of the Prior Art In section rolling where metal plates are transformed to curving plates, for example cylindrically or conically shaped, or to straight metal profiles, typically a bending machine which in its most simple form consists of three rollers, as shown in FIG. 1, is employed. The two lower rollers 1, 2, the transporting rollers, are only able to rotate, while the uppermost roller 3 can be displaced in vertical plane in dependence of the wanted diameter of the finished plate 4. Such bending machine can only provide a bending action in one direction. If S-shaped bending is wanted, this means that the metal 4 after rolling in one direction must be removed from the machine and become inverted and then be bent with an opposite bending. This means low precision and a more expensive operation.

It would be preferable if it was possible to bend plates into S-shape in a simple way without needing to remove the metal from the form.

Another principle is known from US Patent Application Nr. 1 857 325 to Ottenstein. In that case three pairs of rollers are situated in extension of each other, wherein the metal to be bent is passed through each pair of rollers. The uttermost pair of rollers is displaceable across the direction of the metals passing through the pair of rollers so as to provide a bending of the metal. The method has several disadvantages. Firstly the method is difficult with regard to controlling the appropriate bending radius during the metal's passing through the rollers. In fact the system causes that in the displaceable pair of rollers it is only one of the wheels which is shaping the metal. Also, the area between the rollers will be narrow with regard to the passing of the metal, when the bending radius is big, causing a pinching and stretching of the metal which finally is bringing more brittleness to the metal introducing risk of rupture during the bending process or during a following loading of the metal.

Description of the invention

It is therefore the object of the invention to provide an improved profile rolling machine, in particular a profile rolling machine without the above mentioned disadvantages. Especially a profile rolling machine is wanted, wherein it is possible to form metal plates to S-shape during one operation in a simple way, and wherein more precise control of the wanted bending radius is obtainable.

This object is achieved with a profile rolling machine for roller bending of metal profiles, comprising a first set of rollers with at least two rollers, said rollers being in- tended for abutting on each side of the metal profile, and a set of guiding rollers with at least two rollers intended for abutting on each side of the metal profile. The first set of rollers and the set of guiding rollers are spaced and have passing directions in continuation of each other for receiving and successive transport of the metal profile through the guiding rollers and the first set of rollers, wherein the profile rolling ma- chine is adapted to turning or both displacement and turning of the first set of rollers in relation to the guiding rollers so as to, during the passing of the metal profile through the two set of rollers, be imparting to the metal profile a bending which is determined by this turning and possibly displacement and turning.

By using rollers in sets, for example in pairs, so that each set of rollers surrounds the metal profile, it is possible to bend a metal profile to a concave and a convex bending in the same operation in as much as the metal profile is clamped between the rollers and may be moved/bent in one direction or the other direction in relation to the guiding rollers. This is in contradiction to the known embodiment, as shown in FIG. 1, wherein only bending in one direction is possible, in that there is no pair of rollers surrounding the metal profile. In relation to the afore mentioned document US 1 857 325 the rotation of the pairs of rollers causes that the metal not is affected by a single roller, but is affected by both rollers in the pair of rollers, leading to a better outcome of the rolling operation. If the pair of rollers is displaced at the same time, the metal may be guided in perpendicular direction through the pairs of rollers, wherein a clamping and stretching of the metal is avoided, hi this way is achieved a far more easy and precise observance of the wanted bending radius.

According to the above the metal profile is passed successively through the guiding rollers and the first set of rollers. But it does not mean that it is necessarily the guiding rollers through which the metal profile at first should be passed. The direction also could be such that the profile is passed in the opposite direction. Under certain cir- cumstances it could in fact be appropriate during the bending process that the metal profile is moved forward and backward between the rollers.

It should also be noted that the sets of rollers preferably consist of two rollers. However, the invention is generally not limited to two rollers in each set, but a set of rollers can also comprise more than two rollers, if it should be appropriate, hi the following the described set of rollers are considered, without limitation, as consisting of two rollers being placed opposite each other on both sides of the metal to be bent.

In a preferred embodiment the leading rollers are situated as displaceable in a dis- placement direction perpendicular to the metal profile's direction of passage between the leading rollers. The leading rollers can for example be situated on a leading block which can be displaced in a recess, wherein the leading block is provided with a threaded hole with internal thread, so rotation of the threaded bar causes the leading block to be displaced in the recess. By displacing the leading rollers and at the same time rotating the first set of rollers the bending radius will be modified, and the metal can be rolled by passing between the first set of rollers in a direction perpendicular to a line which connects the rotation centres of two rollers situated mutually opposite on each side of the metal.

Li a specific embodiment the first set of rollers are displaceable in only one direction perpendicular to the displacement direction of the leading rollers. By simultaneous turning of the first set of rollers the bending radius of the bent metal will be modified. Said displacement is practically equivalent to the provided displacement of the leading rollers, perpendicular to it.

According to a practical embodiment the roller of the first set of rollers which is intended for abutting on the one side of the metal profile by means of a spacer- connection is connected with the leading roller which is intended for abutting on the

opposite side of the metal profile. This is a simple measure to secure that the space between the first pair of rollers follows the bent metal profile. As it has turned out, it causes very satisfactory results when such an arrangement, connecting displacement of the leading rollers with the rotation of the first set of rollers, is applied.

The first set of rollers can also be placed on a flange so that the roller-shaft is perpendicular to the flange, and the flange can be turned in a plane which is perpendicular to the shafts of the rollers. For example the flange can be turned according to a rotation axis in the middle between the roller-shafts.

As an alternative way of turning a set of rollers this flange may be provided with a tooth profile with a first set of teeth which either is engaging in other teeth on a sliding block so as to cause a turning of the flange when the sliding block is displaced, or is engaging the thread on a toothed bar so as to cause a turning of the flange, when the toothed bar is turned.

While it according to the invention is sufficient to apply a set of rollers in addition to the leading rollers, it has turned out that a higher precision of the manufactured product can be achieved, if the profile rolling machine also includes another set of rollers, wherein the first and the second set of rollers are placed on each side of the leading rollers concerning successive transport of the metal profile through the three sets of rollers.

For example the leading rollers can be placed so that they are displaceable in a dis- placing direction perpendicular to the metal profile's passing direction between the leading rollers. A displacement of the leading rollers on a slide will then result in a bending of the metal profile in relation to the two sets of rollers on each side of the leading rollers.

In order that the first set of rollers and the second set of rollers can follow the bended metal profile optimally, it is preferred that the first set of rollers and the second set of rollers are situated on their own flanges, wherein the axis of the rollers is perpendicu-

lar to the flange, and the flanges can be turned in a plane which is perpendicular to the axis of the rollers.

To modify the bending radius it is preferred that the leading rollers are displaceable in a displacement direction perpendicular to the passing direction of the metal profile between the leading rollers, and that both the first set of rollers and the second set of rollers can only be displaced in a direction perpendicular to the displacement direction of the leading rollers or can only be displaced in a direction along the connection line between the rotation axis of the flanges.

It is possible within the scope of the invention that the first and the second set of rollers are designed for mutually independent movement, allowing for many degrees of freedom for bending, especially in the case of bending of metal during one operation, where the metal is passed through the roller arrangement in only one direction. Such an independent movement, for example turning and displacement, can for example be controlled from a computer and provided with appropriate actuators so as to achieve a high precision of the bending of the metal profile.

hi most cases, however, it is preferable that the first and the second set of rollers are designed for synchronic and mirror inverted movement in relation to the leading roll- ers. This is especially the case when the metal during the bending process is passed forward and backward between the rollers and not only through the rollers in one operation.

For the first and the second set of rollers to follow the movement of the bended profile, the following measure can be taken to achieve the same effect in a very simple way. hi this embodiment the roller from the second set of rollers which is intended for being abutting on the one side of the metal profile, by means of spacer-connections connected with the leading roller intended to be abutting on the opposite side of the metal profile. Also the leading roller intended for being abutting on the one side of the metal profile, is by means of spacer-connections connected with the roller from the first set of rollers and the roller from the second set of rollers which is intended for abutting on the opposite side of the metal profile. This has turned out to be a simple

measure to achieve precise bending with, synchronic movements of the first and the second set of rollers.

Typically, the first set of rollers and the second set of rollers are each placed on its own flange and with their axes perpendicular to the flange. The flanges can be rotated in a plane which is perpendicular to the axes of the rollers.

In a specific embodiment the flanges can be rotated in a plane perpendicular to the axes of the rollers and be displaceable while the leading rollers are stationary. The displacement of the two sets of rollers, typically pairs of rollers, is replacing a displacement of the leading rollers by combination of the simultaneous rotation of the two sets of rollers.

hi a preferred embodiment the leading rollers, however, are displaceable in a direction perpendicular to the metal's passing direction between the leading rollers, and the first and the second set of rollers are displaceable in a direction perpendicular to the displacement direction of the leading rollers.

Alternatively the first and the second set of rollers can be connected with the leading rollers for providing synchronic movement by means of toothed wheels. Every set of rollers can for example be fixed on a flange by means of a toothed wheel which by its teeth is meshing with matching teeth on the side of a slide, carrying the leading rollers. A linear movement of the slide is causing a rotational movement of the flanges.

Concerning production of helically formed bends one or more sets of rollers can be tilting. Preferably the leading rollers are placed on a tilting slide which is adapted to tilting movement in a plane which is parallel with the axes of the leading rollers.

For example the leading rollers are placed on a tilting slide which is adapted to tilt in a plane which is parallel with the axes of the leading rollers.

The tilting slide can be suspended in a curved bearing in a tilting house and comprise a row of first set of teeth following the curved bearing, wherein part of the teeth are

meshing with other teeth for tilting of the tilting slide. The tilting house might further comprise a sliding block having other teeth meshing with the first set of teeth, wherein a displacement of the tilting slide results in tilting of the tilting slide.

hi order to measure if the rolling process makes it possible to achieve the proper bending radius, the profile rolling machine according to the invention can be equipped with one or more cameras, said cameras functionally connected to a computer comprising an analysis program, wherein the computer is programmed to analyze the bending radius and thereafter correct the position of the rollers and their orientation, if the meas- ured radius is not concordant with the stored tolerances.

An alternative measurement of the radius can be taken with two swivelling measuring- arms, both of them mounted on a level with a set of rollers, so that the outermost ends of the arms are resting at their respective sides of the rolled metal. The two arms are also in connection with a measuring unit measuring the deflection from a zero, wherein the deflection via a calculating algorithm can be translated to a value of the bending radius.

Applications of a profile rolling machine are multiple in all branches using profiled metal items in their products, for example the car industry, the train industry and the aviation industry.

Short description of the drawing

The invention is described in more detail with reference to the drawing where

FIG. 1 shows the principle of a profile rolling machine according to the known art,

FIG. 2, a and b, shows views of the front side of a profile rolling machine according to the invention, without and with rollers,

FIG. 3 shows a sketch of the backside of a profile rolling machine according to the invention,

FIG. 4, a and b, shows sketches of the tilting slide,

FIG. 5 shows a cross-sectional view of the profile rolling machine,

FIG. 6 illustrates another embodiment of the invention,

FIG. 7 illustrates a third embodiment of the invention, FIG. 8, a and b, shows examples of tools for the profile rolling machine, FIG. 9 shows an embodiment with measuring-arms,

FIG. 10 shows an alternative principle for rotating movement of the rolling pairs.

Detailed description of the invention

FIG. 2 shows a profile rolling machine 10 according to the invention. The profile rolling machine 10 comprises a first set of bending wheels 11, 11' and a second set of bending wheels 12, 12' suspended in ball bearings 50, and a leading block 13 in a re- cess 26 between the to sets of bending wheels. Each of the bending wheels 11, 11 ', 12, 12' in the first 11, 11 ' and the second set of bending wheels 12, 12' comprises a shaft 14, 14', 15, 15', on which shaft can be mounted a tool in the form of a roller for rolling of a metal profile 4, for example a plate, a tube or another form of metal profile 4. The leading block 13 also comprises a pair of shafts 16, 16', on which can be mounted an appropriate tool for performing rolling, such as rollers 114, 114', 115, 115', 116, 116' with an adapted profile, as shown in FIG. 2b. Examples of rollers 48, 49 are shown in FIG. 8.

The metal profile 4 is passing between the respective sets of rollers during the rolling, which means that a metal profile 4 passes between the first set of shafts 14, 14' and hereafter between the shafts 16, 16' of the leading block and thereafter through the second set of shafts 15, 15'. Compared with the profile rolling machine according to the prior art, as shown in FIG. 1, it is obvious that a tool on the bottom shaft 11 ' of the first set of shafts is functionally equivalent to the lower right roller in FIG. 1 in case of the profile rolling machine being applied in a way where the leading block 13 is guided downwards to create an upwards hollow bending of a metal profile. In the same way a roller on the bottom shaft 15' is equivalent to the bottom roller to the left in FIG. 1, and a roller on the top shaft 16 of the leading block 13 is equivalent to the top roller in FIG. 1.

The first set of bending wheels 11, 11 ' with the shafts 14, 14' are with ball bearings 50 suspended in a first flange comprising a bending wheel plate 17 which can rotate and to a certain degree also be displaced in a first recess 18. A corresponding second

flange comprising a bending wheel plate 19 and a second recess 20 is provided for the second set of bending wheels 12, 12'. In profile rolling with the leading block 13 passed downwards to bend a metal profile, for example a metal profile or a metal bar, the outermost bending wheel plates 17, 19 are going to rotate synchronically with the bending, so that the tools on the two sets of shafts, 14, 14' and 15, 15' are following the bendt metal profile.

By using sets of rollers 114, 114', 115, 115', 116, 116' on the shafts 14, 14', 15, 15', 16, 16', the rollers providing spaces corresponding to the cross-section of the metal profile which is going to be rolled, several advantages can be achieved as described in the following.

If an S-shaped item is going to be produced, it is possible to achieve this in a single operation. With this purpose firstly the leading block 13 is displaced downwards, re- suiting in an upwards directed bending. During the bending, while the metal profile 4 is running through the profile rolling machine in one direction, the leading block now can be moved upwards at first causing a reduction of the bending radius until the bending is going on in the opposite direction. The result is an S-shaped bending.

By letting the leading block run periodically up and down, it is possible to produce a corrugated profile. By having different movements of the leading block 13 in one direction or the other, it is thus possible to produce profiles by variation of the bending in the one direction or the other. The invention thus makes it possible that complex bends can be produced in a simple way and in the same operation. In this way it is avoided that the metal profile 4 must be taken out (removed) and be inverted during the process, or more machines must be applied to produce such complex, bended profiles.

It is a further advantage that only one set of rollers are needed in the process of both concave and convex bending. This is in contrast to those machines necessitating a turning of the item, because in this case, two sets of mirror inverted rollers are needed.

A remarkable advantage by using pairs of tools instead of a three-point-rolling machine, as shown in FIG. 1, is explained in the following. In the three-point-rolling machine, the top side is compressed, while the bottom side is stretched in the bending process. If then, in the machine, the profile is laterally reversed to achieve a bend in the opposite direction, for example to achieve an S-shaped profile, the sides will be compressed and stretched opposite the first process. In this way, control is quickly lost of how much a side has been stretched and compressed in total. To achieve specified bending radii in the final product, it is necessary to carry out several experiments, or a very detailed and complicated calculation has to be done. In praxis, the produced pro- files are not very precise. In a profile rolling machine according to the invention, the metal profile 4 is stretched and compressed in a far more controlled way, as the centreline of the metal profile is known during the whole process, because the metal profile passes in the middle between the three sets of tools. Therefore, experiments and calculations are needed to a far lower degree, and the final product has a high degree of precision.

In the sketch in FIG. 3, an example shows how the turning of the two bending- wheel plates 17, 19 synchronic with the guiding block 13 can be accomplished in a simple way. The upper shafts 14, 15 are by means of control bars 21, 22 connected to the bot- torn shaft 16' in the guiding block 13. In a corresponding way, the bottom shafts 14', 15' are connected to the top shaft 16 in the guiding block 13 by means of control bars 23, 24. hi this way is achieved a cross connection, causing turning of the bending- wheel plates 17, 19 synchronic with the upward or downward directed movement of the guiding block 13. To secure an unhindered turning of the bending- wheel plates 17, 19, said plates are suspended in the recesses 18, 20 in the plate 47, said recesses being elongate in the one direction perpendicular to the direction of movement of the guiding block 13.

The movement of the guiding block 13 is achieved by means of a threaded bar 25, which is meshing with a corresponding internal thread in the guiding block 13, this being shown in greater details in Fig. 4, wherein the threaded bar 25 is meshing with a block 45, said block embedded in the guiding block 45 - shown more detailed in FIG. 4b - said block having internal thread. Rotating the threaded bar 25 causes the guiding

block 13 to move in its recess 26. A ball bearing 29 is causing an appropriate easy going of the threaded bar.

By means of the profile rolling machine 10 according the invention, it is then possible to manufacture bended profiles with an arbitrary number of bends in the one or the other direction. Regarding manufacture of spirals, for instance a banister for a spiral staircase, the guiding block, as indicated in FIG. 2 and in more detail shown in FIG. 4, is provided with a tilting arrangement comprising a tilting slide 27 in a tilting house 28. As described in the preceding, the tilting house 28 can be moved forward and backward in the recess 26. The tilting slide 27 can tilt in the tilting house 28 so as to move the tools on the shafts 16, 16' a definite angle in relation to that plane which is defined by the surface on the profile rolling machine so as to provide the metal profile 4 with a rotation, resulting in a spiral.

The tilting slide 27 is illustrated in FIG. 4a and 4b, FIG. 4a showing the tilting slide 27 in a non-tilted position, whereas FIG. 4b shows the tilting slide 27 in a tilted end position. The tilting slide 27 is on the bottom side provided with a row of teeth 30 meshing with corresponding teeth in a sliding block 31 on a plain bearing 47 being displaced by means of a bar 32. Such a displacement causes a tilting of the tilting slide 27. In the bottom in FIG. 4a and b is shown a threaded bar 25, which is used by moving the tilting house 28 forward and backward in the recess 26 as described in more detail in connection with FIG. 2.

In a practical embodiment, the tilting slide is provided with a tilting groove having a radius of 33 is 35 mm, and the centre of turning has a distance of 15 mm from the edge 34 of the tilting slide. Those tools being placed on the shafts 16, 16' are then so designed that the metal profile to be worked has its centreline passing trough the centre of turning.

A cross-sectional view of the profile rolling machine is shown in FIG. 5 with the same reference numbers as in FIG. 2, 3 and 4. It should be noted that bending- wheels 11, 11', 12, 12' are not shown.

In the above is made use of a cross-connection between the to sets of shafts 14, 14' and 15, 15' to achieve a synchronic movement between the guiding block 13 and the two external sets of tools. This cross-connection is not a must, in as much as between the guiding block 13 and the bending wheel plates 17, 19 can be provided a toothed connection with first set of teeth 51 on the bending- wheel plates 17, 19 and other teeth 52 on the guiding block 13 so as to make a displacement of the guiding block 13, which is caused of the rotation of the threaded bar 25 to cause a turning of the bending- wheel plates 17, 19.

It is also possible to control each set of tools on the two set of shafts 14, 14' and 15, 15' individually - eventually mutual independent - in relation to the guiding block 13. For example can the one set of tools 114, 114' be employed in an initial bending of the metal profile 4 with a relative big bending radius, whereas the second set of tools 115, 115' can be employed in a final bending with a minor bending-radius. Such different movements of the tools an the guiding block 13 can in appropriate way be controlled by means of a computer and actuators being electronically connected to the computer, said actuators in appropriate way acting on the bending- wheel plates 17, 19.

According to the embodiment which is described above, a metal profile 4 can be bended by moving the guiding block in a direction perpendicular to the movement of the metal profile through the profile rolling machine 10. This principle, however, is not limiting the invention, as much as a comparable result can be achieved for an embodiment, wherein the two bending- wheel plates 17, 19 are moved in relation to the guiding block 13. This is illustrated in a- principle-sketch in FIG. 6. Initially, the two outermost sets of tools 36, 37 are placed in a position, wherein their direction of passage 38, 40 is aligned with the direction of passage 39 for that set of tools 41 being mounted on the guiding block 13. With the purpose to achieve a bending of the metal profile 42, both set of tools 36, 37 are moved downwards, which is illustrated by the numbers 36' and 37', simultaneously with turning them to follow the bending- direction of the metal profile 42. hi the figure is also indicated the respective cross- connections (21, 22, 23, 24) between the shafts 15 and 16', 14 and 16', 15' and 16, 14' and 16, respectively.

According to the above embodiments, there are shown a set of tools 36, 37 on each side of the guiding block 13. To illustrate the principle of the invention it is only necessary to make use of a single set of tools 36 in addition to the guiding block 13. This is illustrated in FIG. 7. In this illustration, the metal profile 42' has been bended in an upwards directed curve by moving and turning of the first set of tools 36 during the passing of the metal profile from the left to the right. After this initial bending 42', the tools 36 are being moved down to a new position 36', which is indicated by the arrow 43, causing a variation of a bending direction to a downwards directed bending 42", thus, finally, a S-shaped bending 42', 42" is achieved as the total result. It is here im- portant to notice, that the bending is made possible for reasons of the fact that the metal profile is embedded between the tools 36a, 36b on each side of the metal profile 42'.

Compared to known principles of rolling, the invention according to the embodiment in FIG. 7 is very simple and can be realized at relative low costs. If only one set of tools 36 and one guiding block 13 is employed, the incoming metal profile will show a tendency to be easier displaced in dependence of the bending, which is illustrated with an arrow 44 in FIG. 7. This is a disadvantage in relation to the embodiments illustrated above with one set of tools 36, 37 on each side of the guiding block 13. However, this can in some instances be accepted, so that this simple embodiment, as shown in FIG.

7, is preferred before the other, more expensive and more complicated embodiment of the invention.

It should be noticed that the principle according to the embodiment in FIG. 7 can be retained even in case that the profile rolling machine is further reduced, if only bending in one direction is wanted. If only an upwards directed bending in the metal profile 42' is wanted, it is adequate to have only one set of tools 41 on the guiding block and a single tool 36b. Alternatively one set of tools 36 and only the bottom tool 41b on the guiding block may be employed.

It is noticed, that the tools may be cylindrical rollers or rollers with another profile, wherein the profile is adapted to the cross-section of the metal profile. Different examples of sets of rollers are shown in FIG. 8a and 8b. The illustrated sets of tools each

comprises to rollers 48, 48' and 49, 49' in combination surrounding a cavity 51, 52 equivalent to the cross-section of the metal profile, hi the figure is also indicated the holes 53 for the shafts 14, 14', 15, 15'.

Especially in cases where the bending- wheel plates 17, 19 are not cross-connected to the guiding block 13, the different movements of the tools and the guiding block in appropriate way may be controlled by means of a computer and electronic actuators, connected to it, said actuators acting on the bending-wheel plates and the guiding block in an appropriate way. In this case, it will be possible to pre-program the com- puter with reference to bending of a specific profile and next letting the profile rolling machine according to the invention do the bending-operation under computer control. An eventual tilting of the tilting slide in the guiding block may in that case in appropriate way be implemented in the computer program.

FIG. 9 shows an embodiment of the profile rolling machine 10, wherein on the one pivoting flange 17 is placed a set of pivotable measuring-arms 53, 53', which is indicated with the arrows 54, 54'. The measuring-arms 53, 53' are mounted opposite the one set of rollers 114, 114' in such way that there outermost ends 55, 55' are resting against the surface of the rolled metal. The two arms 53, 53' further are in connection with a measuring device, measuring the deflection in relation to a zero, wherein the deflection by means of a calculating-algorithm can be converted to a value of a bending radius.