EP0907432B1 - Sheet metal bending machine with offset press rollers - Google Patents

Abstract

PCT No. PCT/FR97/00563 Sec. 371 Date Nov. 27, 1998 Sec. 102(e) Date Nov. 27, 1998 PCT Filed Mar. 28, 1997 PCT Pub. No. WO97/46336 PCT Pub. Date Dec. 11, 1997The invention features a sheet metal bending machine constituted by a smooth carrying roller around which the sheet metal is rolled, after bending, and by smooth press rollers against which the carrying roller presses, is characterized in that the carrying roller (2) is supported at one end by a fixed bearing (15) and at its other end by a retractable bearing (18), and in that the press rollers (3, 4) are supported, directly or indirectly (support rollers) by a plurality of bearings (5) supported by a control mechanism called "inclined blocks". (7, 8).

Description

The present invention is in the field working with sheet materials, such as sheets, with a view to bending them, and more precisely it has for object a machine, called "rolling machine", intended to bend the sheets according to the preamble of claim 1.

We know by a patent FR-974,789 (BIGWOOD) such sheet metal rolling machine with support roller upper pivoting and retractable bearing; however a such a machine implements a complex mechanism of bending radius adjustment by drive screw motorized.

We know by a patent FR-2.528.334 from the Applicant a roller rolling machine pivoting support, and akin to this arrangement to the aforementioned device, located above a couple of two smooth rolls of smaller diameter, called pressers, parallel to each other and separable from each other so to obtain different bending radii; these machines of more modest performances than the preceding ones, but of a lower cost suitable for boilermaking workshops in which bending is only part of the task. it is more precisely to such rolling machines that is similar to that of the present invention.

We don't know patents FR-2.528.335 and FR-2.637.206 of the same Applicant of so-called crenellated rollers made of a large said support roller and a double plurality of rollers said pressers of rather small diameter compared to that of the support roller and interpenetrating so as to be able have contact lines with the backing roller plus closer than full rolls would allow, in order to increase the bending precision and to decrease at most the parts remaining straight at the ends of the sheet metal at the inlet and at the outlet of the bending operation; in this type of machine the notched rollers, located at the above the big roll, are grouped in two trains parallel of rollers each train being itself composed several coaxial rollers; in some of the machines like, the bending radius is determined by varying the distance between the pressure rollers (crenellated) and the support roller, by means of a device with inclined planes (cams and wedges inclined) movable sliding against each other by a crank with gravitational indicator dial. These machines, of very high productivity and maneuverability, are generally intended for workshops specializing in mass production of ferrules (curved and welded sheets).

These latest machines have as common feature is that the pressure rollers and support always remain parallel; however in the case of thin sheets (for example of thickness less than two millimeters) or soft material (e.g. aluminum) they have the disadvantage of "marking" the sheets due to the crenellated nature of the pressure rollers.

The object of the present invention is to make available to non-specialized workshops a bending machine which authorizes the bending of sheets fairly wide, thin, and / or made of a material of low hardness.

According to the present invention this object is achieved by a sheet bending machine as defined in claim 1.

So it's in the combination news of known means, and verification of the effectiveness of such a combination, in order to achieve a result, namely the bending of molten sheets and / or thin, with the possibility of rapid and precise change of bending radius, you have to look for the activity inventive, more than in the novelty of the means taken independently.

Preferably the support roller fixed axis is arranged above the set of rollers pressers so that these can be maneuvered vertically from bottom to top by the chocks sloping when they are applied against the sheet metal to be bent, and from top to bottom by the effect of their weight after the bending operation.

It follows from these provisions that the choice of bending radius can be controlled simply by reading a graduation from the dial gravitational indicator of said adjustment means and that, in general, a single passage of the sheet between the rollers is sufficient to give it bending i desired; note however that the operator will always the choice to bend the sheet in a single pass or in several, whereas it is the rolling machine that will ensure the bending precision and no longer the operator himself.

We will note at this stage of the definition of the invention that there are two difficulties to be solved : one concerns the flexibility of the pressure rollers, the other the flexibility of the support roller.

The first difficulty lies in the fact that, so that the contact lines of pressure rollers with the support roller can be fairly close to each other, relative to the measurement diameters of the pressure rollers, so that a sheet introduced between the first pressure roller and the support roller, comes into oblique contact with the upper quarter of the second pressure roller, it is necessary that the diameter pressure rollers is much lower (about 1/3) the diameter of the support roller, and that these rollers are as close as possible to each other; or expected that the flexural strength of a cylindrical beam varies roughly like the power four (D4) of its diameter, their small diameter will cause flexibility important, in practice unacceptable, rollers pressers.

To clarify the concepts mentioned above, the term "as close as possible" means that their center distance e is between d and 1, 5x d , d being the diameter, preferably identical for each, of the pressure rollers, d being itself between 0.2xD and 0.5xD, D being the diameter of the support roller, the effective length of the latter being between 5xD and 10xD, the smallest bending diameter it is possible to obtain with a specific machine being between approximately 1.2 and 1.4xD; it will be noted that the choice of these dimensional relationships also comes under the invention because of the innumerable theoretical possibilities which they offer, a large number of which would prove to be inappropriate in practice, and that only an intuitive appreciation based on a great experience has allowed to eliminate a priori.

A solution proposed by the invention to solve the problem of bending the rollers pressers, consisted in dividing the pressure rollers into sections, each section being supported in rotation, at its ends, by a support piece, the support pieces themselves resting on a beam, preferably in I, so-called intermediate, itself taking indirect support on the general frame of the machine.

However, the rollers being shaped in sections, the problem of the "marking" of the sheets by the end edges of the sections; this problem was solved by shifting the sections in the axial direction, so that the edge end of a section of a pressure roller either always opposite a cylindrical part of a section on the other roller, except for the ends of the rollers themselves; preferably the offset chosen is only slightly more than the thickness of the pieces support, which thickness has been minimized by a judicious choice of the suspension of the sections, and thanks a Z-shaped configuration of the support parts; thanks to what, even very thin sheets can be bent without being marked.

Finally, it remained to be resolved for such a machine the problem of bending, even a weak one, of the backing roller, as well as that of determining the bending radius; it was adapted to the rolling machine of the invention, a solution already applied in another machine type (see: FR-2.637.206, fig. 6 and 7)), namely the interposition between the general inflexible frame and the beam supporting the pressure rollers, with a mechanism "cam ramp" and "sloping wedges", the surfaces in contact of cams and sloping wedges being planes forming with the plane of the axes of the pressure rollers, dihedrons having their oblique edge with respect to the said axes; remember that the obliquity of the holds and their transverse movement allows compensation adjustment bending of the support roller; in the app new made, the mechanism is interposed, at below the pressure rollers, between the beam which supports these rollers and the frame.

All of these provisions combined, namely pressure rollers with reduced center distance, bending radius adjustment by cam ramp and shims sloping, and adjustable stop by graduated dial, allows a precise adjustment by an unqualified operator, and the bending in a single pass so with great productivity.

A second solution proposed by the invention, more particularly suitable for bending following a smaller radius, but always considering the problem of bending, consisted in adding to the pressure rollers divided into sections supported in rotation, a second stage of small diameter rollers arranged above the previous ones and also supported by the same support parts conformed in Z.

Finally according to a third solution proposed by the invention, more particularly adapted to bending thin and fragile sheets (thickness <0.6mm), the rolls of the second stage are continuous over the whole sheet passage width, and are based either on cut rollers with Z-shaped support pieces, more simply on rollers spread over the width of passage and supported by ordinary support parts.

• de caractéristiques permanentes du rouleau d'appui et de ses organes, de compensation de flexion, entraínement et de maintien, et des moyens de manoeuvre des rouleaux presseurs, et
• de caractéristiques alternatives, grosso modo au nombre de trois, des rouleaux presseurs proprement dits, et de leurs moyens support

It should therefore be understood that the rolling machine of the invention is represented as an assembly resulting from the combination

• permanent characteristics of the support roller and its members, of bending compensation, drive and maintenance, and of the maneuvers of the pressure rollers, and
• of alternative characteristics, roughly three in number, actual pressure rollers and their supporting means

• la fig.1 ; est une élévation de coté d'une rouleuse de l'invention en comportant, à ce titre, les caractéristiques premières et secondes, ces dernières relevant d'une première solution de réalisation des rouleaux presseurs,
• la fig.2 est une coupe selon AA de la rouleuse de la figure précédente, illustrant schématiquement et à plus grande échelle la disposition et les rapports dimensionnels des différents rouleaux,
• la fig.3 illustre en plan et à plus grande échelle la disposition constructive des rouleaux presseurs et de leurs pièces support,
• la fig.4 est illustration en perspective d'un palier de la figure précédente, et
• la fig.5 est une vue partielle en perspective écorchée de la rouleuse de la fig.1,
• la fig.6 est illustration schématique en coupe transversale d'une rouleuse selon la deuxième solution de réalisation des rouleaux presseurs,
• la fig.7 est un coupe selon AA de la figure précédente
• la fig.8 est illustration en perspective d'un palier de la figure précédente, et
• la fig.9 est une illustration schématique simplifiée en perpective des rouleaux d'une rouleuse selon la troisième solution de réalisation des rouleaux presseurs, et
• les fig.10 et 11 illustrent, vus en bout, les rouleaux presseurs de la figure précédente avec leur galets support et leur pièces support d'extrémité (fig.10) et intermédiaire (fig.11), et
• la fig.12 illustre dans une direction perpendiculaire à celle des figures précédentes, l'agencement des galets support sur leur pièce support.

The present invention will be better understood, and details will be apparent from the description which will be given of the solutions proposed by the invention, in relation to the figures of the appended plates in which:

• fig.1; is a side elevation of a rolling machine of the invention comprising, as such, the first and second characteristics, the latter pertaining to a first solution for producing the pressure rollers,
• FIG. 2 is a section along AA of the rolling machine of the previous figure, schematically and on a larger scale illustrating the arrangement and the dimensional relationships of the different rollers,
• Fig.3 illustrates in plan and on a larger scale the constructive arrangement of the pressure rollers and their support parts,
• Fig. 4 is a perspective illustration of a bearing in the previous figure, and
• fig.5 is a partial cutaway perspective view of the rolling machine of fig.1,
• FIG. 6 is a schematic illustration in cross section of a rolling machine according to the second solution for producing the pressure rollers,
• fig.7 is a section along AA of the previous figure
• Fig. 8 is a perspective illustration of a landing in the previous figure, and
• FIG. 9 is a simplified schematic illustration in perspective of the rollers of a rolling machine according to the third solution for producing the pressure rollers, and
• Figs. 10 and 11 illustrate, seen at the end, the pressure rollers of the previous figure with their support rollers and their end (fig.10) and intermediate (fig.11) support pieces, and
• Fig.12 illustrates in a direction perpendicular to that of the previous figures, the arrangement of the support rollers on their support piece.

In fig. 1 and / or 2, a rolling machine of the invention consists mainly of a frame made of a massive 1-I frame beam, a roller upper large diameter D, called support roller 2, towards which can be requested from bottom to high, two trains 3,4 of smaller diameter rollers, said pressure rollers, each consisting of a plurality sections of rollers; pressure rollers are supported through support parts such as 5 by an I-beam called intermediate 6.

The intermediate beam 6 can be operated in vertical translation, between guides ends 26, by an operating device of the kind ramp 7 of cams and sloping wedges 8 resting on the beam-frame 1; the ramp 7 is moved in horizontal translation by a couple of jacks such as 9; the setting of the amplitude of the vertical displacement of the support beam, so the gap between the pressure rollers and the support roller, gap which determines the bending radius, is operated by the horizontal displacement of a stop 10, by means of a screw 11 which can be driven manually in rotation by a crank with gravitational indicator dial 12.

Support roller 2 is supported at a first end 13, from which it is rotated by a hydraulic motor 14, by a first bearing 15 very robust with double span, and at its other end 16 by a retractable bearing 17 formed in a tiltable part called "gate" 18; this arrangement allows the axial removal of the sheets after bending

d :

diamètre des rouleaux presseurs (113 mm),

e :

entraxe des rouleaux presseurs (120 mm),

D :

diamètre du rouleau0 d'appui (310 mm),

L :

longueur efficiente du rouleau d'appui 2080 mm);

on notera que les dimensions données entre parenthèses sont celle d'une rouleuse particulière, qu'elles répondent aux rapports sus définis, et qu'elles ne doivent en aucun cas être considérées comme limitatives de la portée de l'invention.In relation to fig. 1 or 2, we locate the following dimensional quantities

d :

diameter of the pressure rollers (113 mm),

e :

center distance of the pressure rollers (120 mm),

D:

diameter of the support roller (310 mm),

L:

efficient support roller length 2080 mm);

it will be noted that the dimensions given in brackets are that of a particular rolling machine, that they respond to the above-defined ratios, and that they should in no case be considered as limiting the scope of the invention.

In Figs. 3 and 4, the pressure rollers each consist of a plurality of sections 31, .32, 33 .. of equal length, and it is noted that the adjacent ends of four adjacent sections are supported by a common support part, such as 51, consisting of a thin wall 53 in Z forming with a sole 54 an angle bracket assembly, this conformation gives the support part a particularly high rigidity, which allows the desired small thickness of the wall and allows two adjacent ends of two sections of the same roller to be as close as possible and thus to have to offset two facing rollers, for example 31 and 41, only by a minimum distance l

Due to the thinness of the wall which does not allow the constitution of stages for the rotating support of a hub, the roller sections each consist of a hollow cylinder, such as 44 visible in section, rotatably mounted on a coaxial central shaft 45 by bearings such as 46 arranged in the vicinity of each end of the section; the tree being itself fixedly engaged in a bore opening 57 of the wall adjacent 53 of a support piece 5 (fig.4); each bore, except for those of the end support parts rollers, supports two neighboring trees coaxial.

In fig. 5, we have taken some elements of the preceding figures with the same references; we also notice the steep wedges such as 8 are maneuverable in oblique directions by relative to the cam ramp 7 and the intermediate beam 6 which supports them by means of a sliding base oblique (see Figure 6 of the aforementioned patent), cranks gravitational crank indicator dials such as 24 and 25, analogous to the 12 sus dial mentioned, which allow, each, the displacement of the respective sloped shim, such as 8, to which it is connected, so as to compensate for the bending of the support roller according to the thickness or nature of the sheet subjected to bending.

Ramp 7 itself is maneuverable in thrust by a couple of hydraulic cylinders such as 9 through a cross piece called "stirrup" 23, to which the ramp is connected.

The gate 18 to bearing 17 is articulated on the frame 1 to be able to tilt (arrow 19) under the effect of a jack 20 between a vertical position in which the bearing 17 encloses the cylindrical-conical end 16, of the support roller 2, and a horizontal position (not shown) in which it releases the end roller to allow removal of the bent sheet. Note that the cylindro-conical shape, even rounded, from the end 16 of the support roller, allows the axis of it to remain fixed during the maneuver of the gate, or again during the extraction of the bent sheet.

The gate cylinder 20, the cylinders 9 for operating the ramp 7 and the hydraulic motor 14 for driving the support roller 2 are supplied with fluid under pressure by a common hydraulic power plant not shown but which is advantageously fixed in the vicinity from the end of the general frame where the engine is located.

So thanks to the adjustment means mainly constituted by gravitational dials, the operator, who does not have to have a particular qualification, to make the various adjustments from an empirically established table, for obtain the desired bend.

Note that, without going outside the framework of the invention, the hydraulic motor can be replaced by a simple electric gear motor or by a brushless type electric motor, and the cylinders hydraulic by ball screws and spindle motor; we also note that the manual operating device can adjustment means can be replaced by a set placed under digital control so that you can do vary the bending radius in a programmed manner during of the passage of the same sheet, and thus finally obtain an oval, elliptical or polygonal shell with angles rounded.

In fig. 6, a rolling machine relaunch of the second solution, has a stage lower rollers such as 31, of axis 31 ′, which are at number of three and which serve as support for the two pressure rollers 32, of axis 32 ', of small diameter and enough close together, located above them.

In fig.7 it appears that roller 32 of the previous figure is a full roller while a support roller 31 is mounted on a bearing balls on a fixed shaft 33; rollers 31 and 32 are supported by support parts 34 in Z such as the part of fig. 8, similar to that of fig, 4, on which are shown the axes 31 'and 32' of the rollers

It is clear from fig. 7 that the rollers, both presser 32 and support 31, of the rolling machine of fig. 6 to 8 are discontinuous sections.

In fig. 9, the pressure rollers 42, according to the third solution, and unlike those of the preceding figures, are continuous, that is to say that they extend over the entire width of passage of the sheets, lengthwise of the rolling machine; Rolls; Coils 42 are supported from place to place by couples rollers such as 58 arranged on either side of a intermediate support part such as 44, or on one side an end support piece such as 45.

Finally, note that the machine can be equipped with automatic variation means radius of curvature during the rolling operation, so as to produce ferrules (rolled sheets) with profile non-circular (for example elliptical, or triangular to rounded corners, etc.).

Claims (9)

1. Machine for bending metal sheets, called a bending machine, of the type of bending machine which consists principally of an upper roll, called a support roll (2), around which the sheet is to be rolled after bending, supported at one end, called the second end (16), by a retractable bearing (17) so that the rolled sheet can be extracted by moving it axially, and of lower smooth rolls, called presser rolls (3,4), intended to press against the support roll, characterized:

   in that the support roll (2) around which the sheet is rolled after bending is connected at its other end, called the first end (13), to a motor (14) and is supported at this first end by a fixed bearing (15), the axis of the support roll remaining fixed, and

   in that the presser rolls (3,4) are arranged in pairs with fixed distances (e) between their axes and are supported by numerous bearings (5), or rolls (31), themselves supported by a beam (6) which itself rests on the frame (1) via a manoeuvring device in vertical translation
2. Machine according to claim 1, characterized :
      in that the distance e between the axes of the presser rolls (3,4) is between d and 1.5 d, d being their diameter, d itself being 0.2D and 0.5D, D being the diameter of the support roll (2), the effective length L of the latter itself being between 5D and 10D.
3. Machine according to either one of claims 1 and 2, characterized :
      in that the presser rolls (3, 4, 32) are divided into sections (31, 32, 32', 33,...), each section being supported for rotation at its ends, by a support component (5, 51, 52,...), the support component (5, 51, 52,...), the support components themselves resting on the intermediate beam (6);
4. Machine according to claim 3, characterized :

   in that the sections (31, 32, 33) of one roll are offset relative to those (41, 42, 43) of the other roll in the axial direction, and are supported by support components (51) consisting of a Z-shaped thin partition (53) forming an angle-bracket-shaped assembly with a sole (54),

   so that the end edge of one section of a presser roll is always opposite a cylindrical part of a section of the other roll, except for the ends of the rolls themselves ; (fig 1-4).
5. Machine according to claim 3, characterized :
      in that the presser rolls (32) divided into sections form a second stage of rolls of small diameter (32, axis 32') positioned above previous rolls (31, axis 31'), and supported themselves also by Z-shaped support components (51), the presser rolls (32) and support (31) being in discontinuous sections.
6. Machine according to either one of claims 1 and 2, characterized :
      in that the presser rolls (42) of the second stage are continuous over the entire sheet passage width and form a second stage of rolls resting either on sectioned rolls (31) either on rollers (58);
7. Machine according to either one of claims 3 to 6, characterized :
      in that the sections of the roll each consist of a hollow cylinder (44) mounted so as to rotate on a coaxial central shaft (45) via rolling bearings (46) positioned in the vicinity of each of the ends of the section ,the shaft itself being engaged securely in an open bore (57) in the adjacent partition (53) of a support component (5,51), each bore, except for those in the support components for the ends of the rolls, supporting two neighbouring coaxial shafts.
8. Machine according to either one of the previous claims, characterized:

   in that the support roll is supported at a first end (13) by a double-length first bearing (15) and at its other end (16) by a retractable bearing (17) made in a tiltable component (18) called a gate, and

   in that the gate (18) with the bearing (17) is articulated to the frame (1) so that it can tilt (arrow 19), under the effect of a jack (20), between a vertical position, in which the bearing (17) fits snugly on a tapered end (16) of the support roll (2), and a horizontal position in which the end of the roll is free so that the bent sheet can be extracted.
9. Machine according to either one of the previous claims, characterized :
      in that the manoeuvring device in vertical translation is a mechanism with "a ramp of cams" (23) and "sloped wedges" (8).

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