EP3278891A1 - Die for bending a boilermaking part - Google Patents

Abstract

The invention relates to a folding die (1) of a boiler room (4) for a folding machine. The matrix comprises two main supports (2, 3) spaced from each other by a distance (dl) dimensioned to allow the passage of said part during its folding between said supports, and two parallel rollers (5, 6). between them in a horizontal plane (P1), pivot connecting means (11, 14, 15) being configured between the rollers and the main supports for pivotably connecting said rollers with respect to said supports with at least one spacing between these rollers, said spacing being dimensioned so that the boiler part bears on said rollers during a force exerted down on said part. 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.

Description

Technic field

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

State of the art

A folding tool arranged on a press brake is made up of a punch having a particular shape with a vee or rounded head, depending on the shape that is to be given to the piece of boilermaking when it is folded, and a folding die that supports the piece of boiler 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 operated vertically by exerting strong pressures of several tons.

Folding dies currently on the market consist of a solid block having a longitudinal v and two longitudinal edges disposed on each side of the longitudinal v, on which bears the piece of boiler before folding. When the punch is actuated, the boiler part is deformed according to the shape of the punch, bearing on the edges formed between the longitudinal edges and the upper ends of the longitudinal v, then the folded portion of this piece enters the vee longitudinal of the matrix.

This folding die design has drawbacks. Indeed, the possibilities of folding of the boiler room are conditioned by the shape of the longitudinal vee and the width of the longitudinal flanges disposed on each side of the vee, especially when it is desired to make counterbends on this piece. In order to reduce the bending angle of the part, it is necessary to use a vee of smaller width, which, conversely, requires increasing the pressure exerted by the punch. Moreover, matrices with a wide vee are expensive because of their design in massive steel blocks requiring extensive machining for the formation of vee. In addition, when folding the piece boiler, it rubs directly on the aforementioned edges of the matrix and undergoes, as a result, significant degradation on these lower outer sides, due to crushing and abrasion. It is then necessary to grind the degraded areas or reload the material in the degraded areas and then machine these areas reloaded, which increases the time and cost of manufacture.

In order to overcome in part these aforementioned drawbacks, those skilled in the art have developed a folding matrix which provides, in addition to the aforementioned characteristics, two rollers arranged at locations corresponding to the two edges. For this, the matrix of the mass comprises two bores partially open over their entire length, machined along the length of the solid in the areas corresponding to the two previous edges, that is to say in the corners formed between the longitudinal edges and the upper ends of the longitudinal vee. Two rollers are mounted pivotally connected respectively in these two open bores, so that two longitudinal portions of said rollers protrude from these open bores, which allows the boiler part to bear on these portions of rollers during its folding. This conception appears for example in the titles US3914972A and JPH0428419A .

A similar design also appears in the titles WO9718907A1 , FR2916991A1 and DE1452813B1 . In these documents, the folding matrix consists of a plurality of supports, these supports being adjacent to each other or slightly spaced apart, and distributed over the entire width of the part to be folded. These supports comprise a shape more or less Vee or U and receive in combination two rollers mounted in pivot connection, in the same manner as described above.

These designs described in the titles US3914972A , JPH0428419A , WO9718907A1 , FR2916991A1 and DE1452813B1 to partially reduce the pressure exerted by the punch during folding and also to reduce the degradation of the workpiece due to the presence of the pivotally mounted rollers. However, the results are not satisfactory enough.

Indeed, particles of material and calamine, due to the abrasion of the boiler part during its folding, penetrate into the open bores constituting the pivot connections with the rollers; As a result, the rollers lock in these open bores and, as a result, no longer fulfill their primary function correctly, namely to reduce the friction against the boiler part during its folding. This piece of boilermaking is therefore always damaged on its outer sides resting on the rollers of the matrix, which further requires grinding the outer sides or reloading material followed by machining.

In addition, the pressures to be exerted with the punch remain high.

Moreover, these types of folding dies have even greater manufacturing costs than the previous type, without a roll.

Another disadvantage remains with these designs described in the titles US3914972A , JPH0428419A , WO9718907A1 , FR2916991A1 and DE1452813B1 . Indeed, the possibilities of folding of the boiler room remain conditioned by the shape of the longitudinal v or U of the solid block or supports arranged next to each other and distributed over the entire length of the piece to be bent.

Summary of the invention

The present invention aims to overcome the aforementioned drawbacks, or at least to reduce them. For this purpose, the invention relates to a folding die of a piece of boilermaking type bar or thick sheet for a folding machine type press brake. The folding die comprises two main supports spaced from each other by a distance dimensioned to allow the passage of said part, during its folding between said supports. Thus, the spacing between these two main supports will depend in particular on the width of the sheet or the diameter of the bar to be folded, when the latter is cylindrical. The folding die also comprises two rollers parallel to each other and arranged in a horizontal plane. In addition, pivot connection means are configured between the rollers and the main supports for pivotally connecting said rollers to said supports with at least a spacing therebetween. This spacing between the rollers is dimensioned so that the boiler part bears on said rollers during a force exerted down on said workpiece.

Thus, the design of the matrix according to the invention consists of moving the two main supports as well as the pivot links between the rollers and said two main supports, outside the work and descent area of the punch-type tool and outside the bearing areas between said rollers and the boiler room.

This prevents deposits of material or calamine become lodged in these pivot connections due to abrasion of said piece rubbing on the rollers during deformation.

The absence of deposition of material or calamine in the pivot links avoids that the rollers are blocked.

In addition, the punch-type tooling which is of dimension adapted to the workpiece, can descend more significantly between the two main supports deported on the sides, which provides a greater deformation of the boiler part by means of said punch . In fact, this deformation of the piece is no longer conditioned by the depth of the vee or the U-shape which is in the working zone of the tooling on the abovementioned dies of the prior art. This vee or this U-shape is offset on the sides of the folding die according to the invention and is no longer below the workpiece, which allows the punch to go deeper between the two rollers. This offers more possibilities of folding boiler parts by means of the same matrix, and makes it possible to achieve lower bending angles on the part, without the need to replace the matrix with another having two rollers closer together.

According to a first embodiment of the folding matrix which is the subject of the invention, the pivot connection means comprise at least two pivot connection sets implemented between the two rollers and the two main supports, for pivotally connecting the rollers. vis-à-vis said supports with at least two different spacings between these rolls, sized so that the boiler part bears differently on said rollers during a force exerted down on said piece. This increases the possibilities of folding boiler parts by means of the same folding die. One could, however, provide an embodiment of the folding die according to the invention comprising a single pivot connection set which, in this case, provides a single possible spacing between the rollers.

According to a design of this first embodiment of the folding matrix, a first pivot connection set is implemented at a first height and a second pivot connection set is implemented at a second height, on the main supports. Preferably, according to this design, the main supports comprise first fixing means on their lower sides and second fixing means on their upper sides. These first and second fixing means are configured to assemble said main supports on a table of the folding machine, in two opposite directions to interchange the position of the two sets of pivot connection, to use one or the other of these two sets of pivot link. These first and second fixing means will depend on the design of the folding machine; they can be identical or different.

Depending on the folding die object of the invention, it may comprise at least one intermediate support configured to be positioned between the two main supports, below the two rollers. This at least one intermediate support comprises on its upper side two semi-cylindrical cavities configured to receive in support the two rollers mounted in pivot connection vis-à-vis the two main supports.

In one embodiment, this at least one intermediate support comprises on its upper side a notch configured between the two cavities to receive the boiler part during its folding. Preferably this notch is vee-shaped. This notch has the advantage of positioning the intermediate piece under the boiler room, without preventing its folding. The notch will indeed be sized to minimize the descent of the boiler room between the two rollers, during its folding and taking into account the recommendation of use.

This type of intermediate support is used as an option in order to reduce the bending of the rollers, without preventing their rotation, when the boiler room exerts significant effort on them. The presence of this intermediate support will however limit the descent of the punching tool, and will therefore be used in rare cases of necessity, when the conditions of descent of the tool allow it. In the opposite case, it will be necessary to replace the supports and rollers of the matrix according to the invention by others more adapted to the forces, without requiring the addition of such an intermediate support.

In another embodiment, this at least one intermediate support is without V-notch. In this case, the at least one intermediate support is configured on the die to be disposed offset from the bearing position of the boiler part on these two rolls, that is to say that it is deported outside the area of support and descent of the punching tool and outside the deformation zone of the boiler room. When such intermediate supports are necessary to reduce the bending of the rollers, it would be possible, for example, to provide two intermediate supports each placed close to the main supports, outside the working zone, with a spacing between these two intermediate supports greater than the width. the piece to be deformed and that of the tool, to allow the passage of said part during its folding between said supports by the tool.

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

According to a first embodiment of the folding die which is the subject of the invention, the two main supports are independent of one another and can be fixed independently on a table of the folding machine. This has the advantage of being able to easily change the spacing between these two main supports, depending on the width of the boiler room.

On the contrary, according to a second embodiment of this folding die, it comprises a sole forming a monoblock element with the two main supports, fixing means being implemented on the sole to assemble the monobloc assembly on a table of the folding machine. This second embodiment makes it possible to increase the stability of the main supports, under the action of the bending forces of the boiler room.

In another variant, one could even consider a matrix comprising a sole and several pairs of main supports attached to the sole or forming a monoblock element therewith, each pair of main supports pivotally receiving two rollers in a similar manner to those described above, with different spacings between the two rollers disposed on each pair of main supports.

According to the invention, a pivot connection is understood to mean 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

• La figure 1 illustre une vue tridimensionnelle d'un mode de réalisation de la matrice de pliage selon l'invention, en cours de pliage d'une pièce de chaudronnerie ;
• Les figures 2 et 3 illustrent deux vues en plan de variantes de conception de supports principaux ;
• Les figures 4 et 5 illustrent deux vues en plan de variantes de conception de supports intermédiaires.

The following description highlights the characteristics and advantages of the folding matrix according to the invention, in support of figures among which:

• The figure 1 illustrates a three-dimensional view of an embodiment of the folding die according to the invention, during the bending of a piece of boiler;
• The Figures 2 and 3 illustrate two plan views of main support design variants;
• The Figures 4 and 5 illustrate two plan views of intermediate media design variants.

detailed description

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

On the figure 1 is illustrated a folding die 1 according to the invention, hereinafter referred to as the "matrix" description. This die 1 is designed to be fixed on a table of a folding machine, the press brake type (not shown). The matrix 1 comprises a first main support 2 and a second main support 3, which are spaced from each other by a distance d1 greater than the width 11 of a piece of boiler which must be bent, the occurrence a plate 4 having for example a thickness of between 10 mm and 40 mm.

The matrix 1 also comprises two rollers 5, 6 which, as illustrated in FIG. figure 1 , are arranged parallel in the same horizontal plane P1. These two rollers 5, 6 extend longitudinally between the two main supports 2, 3 and are mounted in pivot connection on these two main supports 2, 3. The 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 outer sides 4b, 4c of the plate 4 are then supported against the rollers 5, 6. On the figure 1 , the lower outer sides 4b, 4c are deliberately offset from the 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 with the punch 7 which has a width corresponding to the width 11 of the plate 4.

On the figure 1 the die 1 comprises an intermediate support 9, optional, its presence being possibly recommended to limit the bending of the rollers 5, 6 during the actuation of the punch 7, said rollers 5, 6 bearing on this intermediate support 9. Reading of the figure 1 , it is understood that the absence of this intermediate support 9 allows the plate 4 to descend in the spacing 8 located between the two rollers 5, 6, to the bottom of the matrix 1 shown schematically by the plane P2, which allows to make the folding of the plate 4 with low angles of folding. In the presence of this intermediate support 9, it can be shifted with respect to the plate 4, so as not to interfere with the folding of this plate 4. When the intermediate support 9 is disposed under the plate 4, that comprises a notch 10 which avoids any interference on the folding of this plate 4. The dimensioning of this notch 10 will be made taking into account the recommendations for use of the matrix 1. It could also consider two intermediate supports 9 spaced apart from each other a distance greater than the width 11 of the plate 4 and that of the punch 7, to be offset from the working area of the punch 7 on the plate 4.

The Figures 2 and 3 illustrate two variants of non-limiting embodiments of the main supports 2, 3. On the figure 2 , two bores 11, 12 are arranged on the upper portion 2a, 3a of the main support 2, 3 and partially open on its upper edge 13. Similarly, two bores 14, 15 are arranged on the lower part 2b, 3b of said support 2 , 3 and partially open on its lower edge 16. These bores 11, 12, 14, 15 are dimensioned to receive in pivot connection the ends 5a, 5b, 6a, 6b of the two rollers 5, 6. These bores 11, 12, 14 Are rectified and preferably have a surface treatment which reduces the friction of the rollers 5, 6. This design facilitates possible lubrication of the bores 11, 12, 14, 15 to further reduce friction with the rollers 5, 6.

The first two bores 11, 12 constitute a first pivot connection set with the rollers 5, 6 which have a first gap E1, for example 120 mm. The second two bores 14, 15 constitute a second set of pivot connection with the rollers 5, 6 which have a second gap E2, for example 100 mm. The main 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 fastening system implemented on the table of the press brake, which is already known on the former folding dies. However, the design according to the invention makes it possible, unlike the previous folding dies, to turn the main supports 2, 3 and fix them on the press brake table, to adjust either a spacing E1 or a spacing E2 between the two rollers 5.6.

The principle is exactly the same on the embodiment of the main support 2, 3 illustrated in figure 3 . There are indeed four bores 11, 12, 14, 15, the only difference being that the two bores 14, 15 are solid and offset in the material relative 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 rollers 5, 6 which have a third gap E3, for example 80 mm. The second two bores 14, 15 constitute a second set of pivot connection with the rollers 5, 6 which have a fourth gap E4, for example 45 mm. We also finds 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 also being adapted to the fastening system implemented on the press brake, as already exists on the previous folding dies. This mode of designing the figure 3 it is also possible to turn the main support 2, 3 to adjust the rollers 5, 6 either at a spacing E3 or at a spacing E4.

On the Figures 4 and 5 two non-limiting variants of intermediate supports are illustrated. Figures 4 and 5 , the intermediate support 9 comprises on its upper side 9a two semi-cylindrical cavities 21, 22 which are preferably also ground and treated in order to reduce the friction of the rollers 5, 6 which simply rest on said cavities 21, 22, as shown in FIG. illustrates the figure 1 . These two cavities 21, 22 have a spacing E5 which corresponds to one of the four spacings E1, E2, E3, E4 above, or to any other spacing that can be implemented. On the figure 4 , the intermediate support 9 comprises on its lower edge 19, a shoulder 23 similar to the shoulders 17, 18 implemented on the main support 2, 3 of the figure 2 . On the figure 5 , the intermediate support 9 comprises on its lower edge 19, a groove 24 similar to the groove 20 implemented on the main support 2, 3 of the figure 3 . On these Figures 4 and 5 the intermediate support 9 comprises a notch 10 arranged between the two cavities 21, 22, this notch 10 having the shape of a vee, other forms being conceivable such as a rectangular shape. It is also possible to envisage intermediate support variants 9, without notch 10, as explained above.

Alternative embodiments are possible within the scope of the invention. It is possible, for example, to provide rolling bearings arranged between the bores 11, 12, 14, 15 and the ends 5a, 5b, 6a, 6b of the rollers 5, 6. According to the designs previously described through the Figures 1 to 3 , the main supports 2, 3 are independent of one another, which offers great flexibility in adjusting the distance d1 spacing between these two main supports 2, 3, depending on the width l1 of the plate 4. Alternatively, it is possible, in a variant, to provide a sole (not shown) forming with the two main supports 2, 3 a single-piece element, this sole comprising a groove or a shoulder similar to the grooves 20, 24 or the shoulders 17, 18, 23 described above, for fixing this soleplate on the press brake. It would also be possible, in another variant, to provide a sole such as that mentioned above, with several pairs of main supports 2, 3 which receive respectively pivotally connecting several pairs of rollers 5, 6 having different spacings.

The main supports 2, 3 and the intermediate support 9 are in the form of a thick plate. This thickness will be sized according to several characteristics such as the distance d1 between the two main supports 2, 3, the pressures exerted by the punch 7, the spacing between the rollers 5, 6, or other characteristics.

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

Claims (12)

Folding die (1) of a boiler room (4) for a folding machine, comprising two supports (2, 3), two rollers (5, 6) parallel to each other in a horizontal plane (P1) and means pivot connecting means (11, 12, 14, 15) configured between the rollers and the main supports for pivotally connecting said rollers to said carriers with at least one spacing (E1, E2, E3, E4) therebetween rollers, said spacing being dimensioned so that the boiler part bears on said rollers during a downward force exerted on said part, characterized in that the two main supports (2, 3) are spaced apart from each other; other a distance (d1) dimensioned to allow the passage of said part during its folding between said supports. Folding die (1) according to claim 1, wherein 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 main supports (2, 3), for pivotally connecting the rollers with respect to said supports with at least two different spacings (E1, E2, E3, E4) between these rollers, dimensioned so that the piece of boiler (4 ) bears differently on said rollers during a force exerted downwardly on said workpiece. Folding die (1) according to claim 2, wherein a first pivot linkage set (11, 12) is implemented at a first height and a second pivot linkage set (14, 15) is implemented at a first second height, on the main supports (2, 3). Folding die (1) according to claim 3, wherein the main supports (2, 3) comprise first fixing means (18) on their lower sides (16) and second fastening means (17, 20) on their upper sides (13), configured to assemble said supports on a folding machine, in two opposite directions to interchange the position of the two sets of pivot connection (11, 12, 14, 15). Folding matrix (1) according to one of claims 1 to 4, which comprises at least one intermediate support (9) configured to be positioned between the two main supports (2, 3), below the two rollers (5, 6), said at least one intermediate support comprising on its upper side (9a) two semi-cylindrical cavities (21, 22) configured to receive in abutment the two rollers mounted in pivot connection (11, 12, 14, 15) and with respect to the two main supports (2, 3). Folding matrix (1) according to claim 5, wherein the at least one intermediate support (9) comprises on its upper side, a notch (10) configured between the two cavities (21, 22) for receiving the boiler room (4) during its folding. Folding die (1) according to claim 6, wherein the notch (10) has the shape of a vee. Folding die (1) according to claim 5, wherein the at least one intermediate support (9) is configured to be offset from the boiler room to be folded. Folding die (1) according to claim 8, which comprises two intermediate supports (9) spaced from each other by a distance dimensioned to allow the passage of the boiler part (4) during its folding between said supports intermediate. Folding matrix (1) according to one of claims 1 to 9, wherein the pivot connection means are implemented by bores (11, 12, 14, 15) on the main supports (2, 3) configured to receive directly in pivot connection, each, a portion (5a, 5b, 6a, 6b) of roll (5, 6). Folding matrix (1) according to one of claims 1 to 9, wherein the pivot connection means are implemented by rolling bearings arranged on the main supports (2, 3) and configured to each receive a portion ( 5a, 5b, 6a, 6b) of roll (5, 6). Folding matrix (1) according to one of claims 1 to 11, which comprises a sole forming a monobloc element with the two main supports (2, 3), fastening means being implemented on the sole to assemble the monobloc assembly on the folding machine.

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