FR3078274A1 - FOLDING MATRIX OF A CHAUDRONNERIE PIECE WITH REINFORCING BARS - Google Patents

Abstract

The invention relates to a folding die (1) of a boiler room (4) for a folding machine. The die comprises two supports (2, 3) spaced apart from one another to allow the said piece to be folded between these supports, and two rollers (5, 6) mounted in pivot connection on the supports with a spacing between these rollers allowing the boiler room to bear on said rollers during folding. The matrix makes it possible to increase the folding and counter-bending capabilities of the parts by increasing the radii of curvature, and reduces the degradation of the part during its folding. The folding die comprises two reinforcing bars which extend between the two supports so as to stiffen them, said reinforcing bars being arranged respectively below the rollers (5, 6) with a spacing between them, said spacing being dimensioned to release said reinforcing bars outside the deformation zone of the boiler room.

Description

FOLDING MATRIX OF A BOILER WORKPIECE WITH BARS

BRACE

Technical area

The present invention relates to the field of tools for machines for bending sheet metal parts such as bars or thick sheets, and relates particularly to a bending die for such sheet metal parts, the die being mounted on the folding machine table. Such a folding machine is of the press brake type.

State of the art

A folding tool arranged on a press brake consists of a punch and a folding die. The punch has a particular shape with a vee or rounded head, depending on the shape that one wishes to give to the sheet metal part when it is folded; the folding die supports the sheet metal part during the action of the punch.

The folding die is mounted on a table or a base of the press brake and the punch is mounted on a tool holder configured to be actuated vertically by exerting high pressures, of several tons.

A folding matrix has already been developed which has been the subject of patent applications published under the numbers FR3032367A1 and EP3278891A1. The design of this folding matrix overcomes the many drawbacks of the existing previous folding dies and mentioned in these patent applications FR3032367A1 and EP3278891A1.

Summary of the invention

The present invention aims to further optimize the performance of the folding matrix which has been the subject of patent applications published under the numbers FR3032367A1 and EP3278891A1, in particular with the aim of allowing the bending of bars of larger sections or of sheets (or plates) of greater thickness. Another object is to guarantee the proper rotation of the rollers when bending these bars of larger sections or of these thicker sheets.

To this end, the invention relates to a folding die for a piece of sheet metal work of the bar or thick sheet metal type. Such a folding die is used on a folding machine of the press brake type.

The folding matrix according to the invention incorporates all the essential characteristics of the folding matrix described in the patent applications published under the numbers FR3032367A1 and EP3278891A1.

The folding matrix comprises two supports spaced from each other by a dimensioned distance to allow passage between said supports of the sheet metal part during its folding. Thus, the spacing between these two supports will depend in particular on the width of the sheet or the diameter of the bar to be folded.

The folding die also includes two rollers parallel to each other and arranged in a horizontal plane.

In addition, pivot connection means are configured between the rollers and the supports to mount said rollers in pivot connection with respect to said supports with at least one spacing between these rollers. This spacing between the rollers is dimensioned so that the sheet metal work piece is supported on said rollers during a downward force exerted on said piece by a tool of the punch type.

Thus, the folding die according to the invention makes it possible to offset the two supports as well as the pivot connections between the rollers and said two supports, outside the working and lowering area of the punch-type tool and outside the bearing areas between said rollers and the sheet metal part.

This prevents deposits of material or scale from becoming lodged in these pivot connections due to abrasion of said part rubbing on the rollers during deformation. The absence of material or scale deposits in the pivot connections prevents the rollers from jamming.

In addition, the punch type tool which is of dimension adapted to the part, can descend more significantly between the two supports due to their offset on the sides, outside the working area, which allows deformation larger of the sheet metal part by means of said punch. Indeed, this deformation of the part is no longer conditioned by the depth of a vee located in the working area of the tool on the dies of the prior art, which allows the punch to descend more deeply between the two rollers. This offers more possibilities for bending sheet metal parts using the same die, and enables smaller bending angles to be achieved on the part, without the need to replace the die with another one having two closer rollers.

According to the invention, the folding die comprises two reinforcing bars extending between the two supports so as to stiffen between them said two supports, said reinforcing bars being arranged respectively below the rollers with a spacing therebetween, said spacing being dimensioned for said reinforcing bars is clear of the deformation zone of the sheet metal work piece.

The establishment of the two reinforcing bars consolidates the two supports therebetween, which makes it possible to maintain the pivot connections implemented between the rollers and the two supports along pivot axes which are substantially coaxial and horizontal. This consolidation of the supports is opposed to the bending of the rollers when the sheet metal work piece rests on its rollers and is deformed by the tool. This guarantees proper rotation of the rollers despite the high forces exerted by the tool on the workpiece and transferred to the folding die.

According to one embodiment of the folding die that is the subject of the invention, the pivot connection means comprise at least two sets of pivot connection implemented between the two rollers and the two supports, to mount the screw rollers in pivot connection. opposite said supports with at least two different spacing between these rollers. These spacings are dimensioned so that the sheet metal part bears differently on said rollers during a bending force exerted by the tool on said part. This increases the possibilities of folding sheet metal parts using the same folding die. However, an embodiment of the folding die could be provided according to the invention comprising a single pivot connection set which, in this case, offers only one possible spacing between the rollers.

According to one embodiment of the folding matrix, a first pivot connection set is implemented at a first height on the supports, preferably near their lower sides, and a second pivot connection set is implemented at a second height on the supports, preferably near their upper sides. The supports include first fixing means on their lower sides and second fixing means on their upper sides. These first and second fastening means are configured to assemble said supports on a table of the folding machine, in two opposite directions making it possible to invert the positions of the two sets of pivot connection, to use one or the other of these two sets of pivot links. These first and second fixing means will depend on the design of the folding machine; they can be the same or different.

According to this embodiment, preferably, the folding die comprises two pairs of rollers, the two pairs of rollers being arranged respectively in the two sets of pivot connection. According to the direction of positioning of the supports on the table of the folding machine, one of the two pairs of rollers - the one located above - receives in support the piece of sheet metal during its deformation by the punch and the other of the two pairs of rollers the one located below - constitutes the pair of reinforcement bars making it possible to consolidate the two supports between them during the deformation of the sheet metal work piece.

In an embodiment of the folding die according to the invention, the rollers receiving in support the sheet metal part during its deformation are removable from the supports.

In one embodiment, with such removable rollers of the supports, the folding die comprises at least one pair of rings configured to add said rings to the rollers so as to reduce the spacing between these rollers, the sheet metal part bearing on said said rings. Thus, the rollers receive the sheet metal work piece indirectly, by means of the rings. The rings are of lengths less than the spacing between the two supports and greater than the width of the sheet metal part so that the latter is properly supported on said rings. Preferably, the matrix comprises at least two pairs of rings, the rings being added concentrically on the rollers, the sheet metal part bearing on the external rings added on the rollers, during its deformation by the punch. This implementation makes it possible to modify the spacing between the rollers by adding one or more rings concentrically on each of said rollers. One could also provide several sets of rings added individually to the rollers, the thicknesses of the rings varying so as to modify the spacing between the rollers.

In one embodiment of the folding die, the pivot connection means are implemented by bores on the supports, these bores being configured to receive directly in pivot connection, each, a portion of roller. In an alternative embodiment, these pivot connection means are implemented by rolling bearings arranged on the supports and configured to receive, each, a portion of roller.

According to the invention, the term “pivot connection” means a pivot connection as such or a sliding pivot connection, the conceivable designs of the pivot connection means not being limiting.

Brief description of the figures

The following description highlights the characteristics and advantages of the folding die according to the invention, with the aid of figures among which:

FIG. 1 illustrates a three-dimensional view of an embodiment of the folding die according to the invention, during the folding of a sheet metal work piece;

Figures 2 and 3 illustrate two plan views of alternative carrier designs.

detailed description

In the following description, the same references are used to designate the same characteristics or their equivalents in the figures.

In Figure 1 is illustrated a folding die 1 according to the invention, called in the following description "die". This matrix 1 is designed to be fixed on a table of a folding machine, of the press brake type (not shown). The matrix 1 comprises a first support 2 and a second support 3, which are spaced from each other by a distance dl greater than the width 11 of a piece of sheet metal that should be folded, in the occurrence a plate 4 having for example a thickness between 10 mm and 40 mm.

The matrix 1 also comprises two first rollers 5, 6 which, as illustrated in FIG. 1, are arranged in parallel in the same horizontal plane P1. These two first rollers 5, 6 extend longitudinally between the two supports 2, 3 and are mounted in pivot connection on these two supports 2,3. The first two rollers 5, 6 are spaced from each other. When the punch 7 exerts pressure on the upper side 4a of the plate 4, the latter bends along the line of contact with the punch 7, the two lower external sides 4b, 4c of the plate 4 are then pressed against the first rollers 5, 6. In FIG. 1, the lower external sides 4b, 4c are deliberately offset from the first rollers 5, 6, for a better reading of this figure 1. It can be seen that the folded portion of the plate 4 penetrates into the 'spacing 8 between the two rollers 5, 6. It is the same for the punch 7 which has a width corresponding more or less to the width 11 of the plate 4. During its folding, the plate 4 can descend into the spacing 8 located between the first two rollers 5, 6, to the bottom of the die 1 shown diagrammatically by the plane P2, which makes it possible to fold the plate 4 with small folding angles.

As illustrated in FIG. 1, the die 1 comprises two second rollers 9, 10 arranged below the first rollers 5, 6, preferably with a spacing different from that of the first rollers 5, 6. These two second rollers 9, 10 are arranged in the same horizontal plane P3 and are mounted in pivot connection on the two supports 2,3, as for the first rollers 5, 6. During the deformation of the plate 4 bearing on the first two rollers 5, 6, both second rollers 9, 10 constitute reinforcing bars making it possible to consolidate the two supports 2, 3 mounted on the table of the press brake.

Figures 2 and 3 illustrate two alternative embodiments, not limiting, of the supports 2, 3. In Figure 2, two first bores 11, 12 are arranged on the upper part 2a, 3a of the support 2, 3 and partially open on its upper edge 13. Similarly, two second bores 14, 15 are arranged on the lower part 2b, 3b of said support 2, 3 and partially open on its lower edge 16. The first bores 11, 12, are dimensioned to receive in pivot connection the ends 5a, 5b, 6a, 6b of the first two rollers 5, 6. Similarly, the second bores 14, 15 are dimensioned to receive in pivot connection the ends 9a, 9b, 10a, 10b of the two second rollers 9, 10. These bores 11, 12, 14, 15 are rectified and preferably have a surface treatment which reduces the friction of the first and second rollers 5, 6, 9, 10. This design facilitates possible lubrication of the bores 11, 12, 14, 15 for red follow even more friction with the rollers 5, 6.

Preferably, the rollers 5, 6, 9, 10 all have an identical diameter, for example equal to twenty-five centimeters (25cm). One could however provide first rollers 5, 6 with a first diameter and second rollers 9, 10 with a second diameter.

The first two bores 11, 12 constitute a first set of pivot connection with the first rollers 5, 6 which have a first spacing El, for example of 120 mm. The two second bores 14, 15 constitute a second set of pivot connection with the second rollers 9, 10 which have a second spacing E2, for example of 100 mm. Each support 2, 3 has on its upper edge 13 and on its lower edge 16 two shoulders 17, 18 whose dimensions are adapted to the fixing system implemented on the press brake table, which is already known on anterior folding dies. The design according to the invention allows, however, unlike previous folding dies, to turn the supports 2, 3 and fix them on the press brake table, to invert the first rollers 5, 6 and the second rollers 9, 10 and adjust either a spacing El or a spacing E2 between the two rollers 5, 6 or 9, 10 used for the deformation of the plate

4. It is therefore understood that, according to the direction of positioning of the supports 2, 3 on the table of the press brake, either the first two rollers 5, 6 serve as support for the plate 4 during its deformation and the two second rollers 9, 10 constitute the reinforcement bars consolidating the supports 2, 3 during said deformation of the plate 4, or the reverse.

The principle is exactly the same on the embodiment of the support 2, 3 illustrated in FIG. 3. There are indeed the four bores 11, 12, 14, 15, the only difference being that the two bores 14, 15 are full and offset in the material with respect to the lower edge 16 of said support 2, 3. The first two bores 11, 12 constitute a first set of pivot connection with the first rollers 5, 6 which have a third spacing E3, for example of 80 mm. The two second bores 14, 15 constitute a second pivot connection set with the second rollers 9, 10 which have a fourth spacing E4, for example of 45 mm. There is also the shoulder 18 on the lower edge 16 of the support 2, 3. A groove 20 replaces the shoulder 17 on the upper edge 13 of said support 2, 3, this groove 20 being also adapted to the fixing system used on press brakes, as it already exists on previous folding dies. This design mode of FIG. 3 also makes it possible to return the supports 2, 3 to either use the first rollers 5, 6 at a spacing E3 as support for the deformation of the plate 4 while the second rollers 9, 10 stiffen the supports 2, 3 during the deformation of this plate 4, or use the second rollers 9, 10 at a spacing E4 as support for the deformation of the plate 4 while the first rollers 5, 6 stiffen the supports 2, 3 during the deformation of this plate 4.

The first rollers 5, 6 and the second rollers 9, 10 are mounted in pivoting connection sliding on the bores 11, 12, 14, 15, which allows them to slide very easily for their disassembly of the supports 2, 3 and their mounting on these supports 2, 3. This removable nature of the first and second rollers 5, 6, 9, 10 advantageously makes it possible to be able to add on these rollers sets of rings 21 to artificially modify the diameters of the rollers 5, 6, 9, 10. On this FIG. 1, two first rings 211, 212 are arranged directly on the first rollers 5, 6 and constitute a first set of rings 21 and two second rings 213, 214 are arranged on the rollers 5, 6 by means of the first rings 211,

212 and constitute a second set of rings 21. The first rollers 5, 6, the first rings 211, 212 and the second rings 213, 214 are concentric with one another. In this case, the plate 4 is supported on the second rings 213, 214 arranged outside. Thus, the addition of the first rings 211, 212 on the first rollers 5, 6 makes it possible to reduce the spacing between these rollers 5, 6 for the first time; and the addition of the second rings 213, 214 on the first rings 211, 212 makes it possible to further reduce the spacing between these first rollers 5, 6. In addition, the installation of these sets of rings 21 makes it possible to limit the deflection of the first rollers 5, 6 during the deformation of the plate 4, which promotes proper rotation of the first rollers 5, 6 when folding a plate 4 of significant thickness, of the order of 30 to 40 mm. In FIG. 1, sets of rings 21 are added only on the first rollers 5, 6, but similar sets of rings can be provided on the second rollers 9, 10. As illustrated in FIG. 1, the first rings 211, 212 and the second rings 213, 214 have a length less than the distance dl separating the two supports 2, 3 and greater than the width 11 of the plate 4. The number of ring sets 21 is not limited to two, we could provide one, three or four, for example. One can also play on the thickness of the rings 211, 212, 213, 214 to more or less reduce the spacing between the first rolls 5,6.

Alternative embodiments are possible within the scope of the invention. One can for example provide rolling bearings arranged between the bores 11, 12 and the ends 5a, 5b, 6a, 6b of the first rollers 5, 6 similarly between the bores 14, 15 and the ends 9a, 9, 10a, 10b second rollers 9, 10.

According to the designs described above through Figures 1 to 3, the supports 2, 3 are consolidated vis-à-vis each other thanks to the reinforcing bars formed either by the first rollers 5, 6 or by the second rollers 9, 10, according to the direction of positioning of the supports 2, 3 on the table of the press brake.

One could however envisage an alternative embodiment with only the first rollers 5, 6 on which the sets of rings 21 are optionally mounted, and with reinforcement bars other than the second rollers 9, 10, that is to say with sections other than cylindrical or not fulfilling the function of rollers receiving the part during its bending. These reinforcing bars will be arranged respectively below the first rollers 5, 6 with a spacing therebetween, in a more or less similar manner to the two second rollers 9, 10, said spacing being dimensioned to release said reinforcing bars outside the deformation zone of the plate 4.

One could also envisage another alternative embodiment with supports 2, 3 similar to those of FIGS. 2 and 3, as described above, the first pivot connection set implemented by the first two bores 11, 12 and the second set of pivot connection implemented by the two second bores 14, 15 allowing both to receive the first rollers 5, 6. Reinforcement bars, other than the second rollers 9, 10, that is to say with sections other than cylindrical or not fulfilling the function of rollers receiving the part during its bending, will be arranged more or less halfway between the first bores 11, 12 and the second bores 14, 15, outside the deformation zone of plate 4.

In the embodiment of Figures 1 to 3, the rollers 5, 6, 9, 10 are slidably mounted on the supports 2, 3, which offers great flexibility in adjusting the distance dl of spacing between these two supports 2 , 3, depending on the width 11 of the plate 4.

The supports 2, 3 have the form of a thick plate. This thickness will be dimensioned as a function of several characteristics such as the distance dl between the two supports 2, 3, the pressures exerted by the punch 7, the spacing between the rollers 5, 6, or even other characteristics.

The supports 2, 3 and the rollers 5, 6, 9, 10 will be made of treated metals comparable to those used for the matrices of the prior art.

Claims (10)

1. Folding die (1) of a sheet metal part (4) for a folding machine, comprising two supports (2, 3) spaced from each other by a distance (dl) dimensioned to allow the passage of said piece during its folding, two rollers (5, 6) parallel to each other in a horizontal plane (PI) and pivot connection means (11, 12) configured between the rollers and the supports for pivotally mounting said rollers with respect to said supports with at least one spacing (E1, E3) between these rollers allowing the sheet metal work piece to bear on said rollers during its folding, characterized in that said folding matrix comprises two reinforcing bars (9, 10) which extend between the two supports (2, 3) so as to stiffen them between them, said reinforcing bars being disposed respectively below the rollers (5, 6) with a spacing therebetween, said spacing being dimensioned to release said barr reinforcement outside the deformation zone of the sheet metal part. 2. folding matrix (1) according to claim 1, in which the pivot connection means comprise at least two pivot connection sets (11, 12, 14, 15) implemented between the two rollers (5, 6) and the two supports (2, 3), for pivotally mounting the rollers with respect to said supports with at least two different spacings (El, E2, E3, E4) between these rollers, dimensioned so that the piece of sheet metal work ( 4) take support differently on said rollers during a force exerted downwards on said part. 3. Folding die (1) according to claim 2, wherein a first pivot connection set (11, 12) is implemented at a first height and a second pivot connection set (14, 15) is implemented at a second height, on the supports (2, 3). 4. Folding die (1) according to claim 3, in which the supports (2, 3) comprise first fixing means (18) on their lower sides (16) and second fixing means (17, 20) on their upper sides (13), configured to assemble said supports on a table of the folding machine, in two opposite directions making it possible to invert the position of the two sets of pivot connections (11, 12, 14, 15). 5. folding die (1) according to one of claims 2 to 4, which comprises two pairs of rollers (5, 6, 9, 10), the two pairs of rollers being disposed respectively in the two sets of pivot connection, one (5, 6) of the two pairs of rollers located above receiving the sheet metal work piece during its deformation and the other (9, 10) of the two pairs of rollers located below constituting the pair of bars reinforcement. 6. Folding die (1) according to one of claims 1 to 5, in which the rollers (5, 6) are removable from the supports. 7. Folding die (1) according to claim 6, which comprises at least one pair of rings (21) configured to be added to the rollers (5, 6) so as to reduce the spacing between these rollers, the piece of boilermaking supported on the rings (211, 212, 213, 214). 8. Folding die according to claim 7, in which the rings (211, 212, 213, 214) are of lengths less than the distance (dl) between the two supports and greater than the width (11) of the piece of boilermaking (4). 9. folding die (1) according to one of claims 7 or 8, which comprises at least two pairs of rings (21), the rings (211, 212, 213, 214) being added concentrically on the rollers ( 5, 6), the sheet metal part (4) resting on the outer rings (213, 214). 10. folding matrix (1) according to one of claims 1 to 9, in which the pivot connection means are implemented by bores (11, 12, 14, 15) on the supports (2, 3), these bores being configured to receive directly in pivot connection, each, a portion (5a, 5b, 6a, 6b, 9a, 9b, 10a, 10b) of roller (5, 6, 9, 10).