EP0338944A1 - Method and device for controlling the resilience by bending of an elongated element such as a tube. - Google Patents

Method and device for controlling the resilience by bending of an elongated element such as a tube. Download PDF

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Publication number
EP0338944A1
EP0338944A1 EP89420106A EP89420106A EP0338944A1 EP 0338944 A1 EP0338944 A1 EP 0338944A1 EP 89420106 A EP89420106 A EP 89420106A EP 89420106 A EP89420106 A EP 89420106A EP 0338944 A1 EP0338944 A1 EP 0338944A1
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EP
European Patent Office
Prior art keywords
tube
elbow
bending
elastic return
located behind
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89420106A
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German (de)
French (fr)
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EP0338944B1 (en
Inventor
Jean Lafrasse
Jean-Paul Chastan
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Eaton Leonard Picot SA
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Eaton Leonard Picot SA
PICOT
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Publication date
Application filed by Eaton Leonard Picot SA, PICOT filed Critical Eaton Leonard Picot SA
Priority to AT89420106T priority Critical patent/ATE70473T1/en
Publication of EP0338944A1 publication Critical patent/EP0338944A1/en
Application granted granted Critical
Publication of EP0338944B1 publication Critical patent/EP0338944B1/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D7/00—Bending rods, profiles, or tubes
    • B21D7/14—Bending rods, profiles, or tubes combined with measuring of bends or lengths
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S72/00—Metal deforming
    • Y10S72/702—Overbending to compensate for springback

Definitions

  • the present invention relates to a method for controlling the elastic return, during a bending operation of a deformable elongated element.
  • the invention also relates to a device, associated with a bending tool, which is intended for the implementation of this control method.
  • This invention applies more particularly, but not exclusively, to the control of the elastic return of the tubes, on automatic machines for bending the tubes.
  • the bending of the tubes, aimed at forming on these tubes bends characterized by their radius and their angle, is carried out by means of tools usually comprising: a forming roller rotating around an axis orthogonal to the initial direction of the tube to be bent, having at its periphery an annular groove and supporting, or forming by itself, a first jaw - a second jaw carried by a bending arm mounted rotating around the axis of the forming roller, the second jaw being movable on the arm and cooperating with the first jaw to grip and drive the tube to be bent - a strip parallel to the initial direction of the tube, located behind the jaws and intended to be applied laterally against the tube to be bent.
  • this part is clamped between the two jaws and driven forward by the control of rotation of the bending arm, so as to wind in the groove of the forming roller, while that the strip, applied laterally against the tube behind the part being bent, avoids any unwanted deformation of the tube beyond the part to be bent, and ensures the reaction to bending forces.
  • the dimensional characteristics of the forming roller determine the radius of the bend thus formed on the tube, while the angle of rotation of the bending arm determines the angle of the bend.
  • the final angle of the elbow is always less than the angle of the controlled rotation of the bending arm.
  • a known method for controlling the elastic return consists in detecting the extent of this elastic return on the bending machine, by means of mechanical probes.
  • the implementation of this known method requires an opening of the jaws, releasing the tube in its part which has just been bent, the feelers coming into contact with the region of the tube situated in front of the bend formed.
  • the main drawback of the existing process lies in the fact that after detection of the elastic return, it is practically impossible to resume bending the tube, taking account of this elastic return, to bring the elbow exactly to the desired angle value. Indeed, the tube should be clamped again between the two previously opened jaws. However, it is impossible to pinch the tube again in a manner identical to the previous bending. This results in a marking of the tube by the jaws, which makes this tube unusable subsequently. Thus, the tube used to control the elastic return is a lost tube, which is difficult to accept in the case of expensive tubes due to their dimensions and / or their material.
  • the probes currently used for controlling the elastic return constitute on the bending machines additional bulky and annoying devices, located in the bending zone.
  • the elastic return of the tube takes place freely, while this tube remains clamped between the jaws of the bending tool.
  • the detection of the elastic return is made in the released part of the tube, located behind the elbow, away from the bending zone.
  • the bending can then be resumed, taking into account the elastic return, without at any time interrupting the tightening of the tube in its part located in before the elbow therefore without marking the tube; the tube used for controlling the elastic return is therefore never lost, and therefore the principle of such a procedure proves to be advantageous.
  • document DD-A-109331 only proposes, for measuring or locating the elastic return of the tube, a device comprising a part provided with an angular scale, mounted on the released part of the tube, and an optical sighting system. mounted on the frame of the bending machine.
  • Such a device therefore forms a kind of external measuring instrument, and its implementation requires the addition of complementary elements on the machine and on the tube to be bent, which constitutes a first drawback.
  • the aim of the present invention is to allow rapid and automatic measurement and correction of the elastic return, without the addition of external measurement elements, in particular on the tube, and also by eliminating human intervention such as aiming and reading a graduation, this by simple means and particularly suitable for bending machines with numerical control, currently very common, having means of calculation.
  • the invention relates to a method for controlling the elastic return, when bending an elongate deformable element such as a tube by winding this element around a forming member, with clamping of this element in a situated part. in front of an elbow to be formed, the method providing in known manner that after execution of the elbow, the part of the elongated element such as a tube situated in front of this elbow remains tight, while the part of said element situated in the rear of the elbow is released, and that a measurement or a marking, determining the extent of the elastic return, is carried out on the released part of said element located behind the elbow, and this method being characterized in that the detection of the elastic return is carried out, after release of the elongated element such as tube in its part situated behind the elbow, by making this element and the forming member describe a rotation around the axis of the elbow, and by detecting the instant when the part of said element situated behind the elbow reaches a determined position, as well as the angular position of the forming member at this instant; then
  • the part of the elongated element such as a tube, situated behind the elbow can in particular be released after the elbow has been executed by loosening the clamp holding said element and by spacing the strip applied laterally against this element during bending, in the case of a bending machine provided with a clamp and a strip.
  • the release of the part of the elongated element such as a tube, situated behind the elbow is carried out only after the forming member has described a rotation in the opposite direction to that of the bending previously carried out, and of value equal to the theoretical elastic return angle, reduced by a small angular difference.
  • the device according to the invention associated with a bending tool comprises in known manner a detection means disposed behind the bending tool, and capable of detecting at minus a position of the part of the curved element situated behind the elbow, after release of this part, the detection means being provided for detecting the instant of passage of the part of the curved element, situated behind the elbow , in a determined position, this during the rotation of this element and of the forming member, the angular position of the forming member at the time of this detection providing an indication of the extent of the elastic return.
  • the detection means is, for example, a photoelectric cell detecting the instant when the part of the curved element located behind the elbow intersects a light ray during its rotation.
  • the detection means is carried by the strip belonging to the bending tool, applied laterally against the elongated element such as a tube to be bent, this strip being spaced from said element and placed in a determined position, to release the part of the element under consideration located behind the elbow.
  • the detection means is carried by the rear end of the strip.
  • FIGS 1 to 5 of the drawing very schematically show the bending tool of a tube bending machine, and they illustrate the successive phases of a process for controlling the elastic return of a tube, in accordance with the present invention.
  • these figures show a tool comprising a forming roller 1, mounted rotating around its axis 2 and having, at its periphery, a groove 3 at least partially annular.
  • a bending arm 4 Around the axis 2 is also mounted rotating a bending arm 4, which carries a jaw 5 movable in the radial direction.
  • the jaw 5 cooperates with a part 6 of the forming roller 1, located opposite, to clamp a bending tube 7 which is initially rectilinear, the initial axis of the tube 7 being indicated at 8.
  • the bending tool further comprises a strip 9, extending parallel to the axis 8 of the tube to be bent 7, and itself having a longitudinal groove 10.
  • the strip 9 is movable transversely, as indicated by an arrow 11, to be able to be applied laterally against the tube 7, behind the part to be bent, or separated from the tube 7.
  • this strip 9 can be moved longitudinally, therefore parallel to the axis 8, to accompany the tube 7 in its advance movement described during bending.
  • the bending tube 7 is held, behind its bending part, by means of a clamp 12 carried by a carriage not shown, movable in the direction of the axis 8.
  • the movement of the carriage provided with the clamp 12 allows to bring, at the level of the tool previously described, the part of the tube 7 which must be bent.
  • this tube 7 is clamped between the movable jaw 5 and the part 6 of the forming roller 1, the strip 9 is also applied against the tube 7, and the bending arm 4 d is rotated '' a certain angle A around axis 2, in the direction of arrow F, as shown in Figure 1 which indicates the stop position of the arm 4 at the end of bending.
  • the tube 7 is first bent to a known value, by controlled rotation of the bending arm 4, according to the angle A, as described previously with reference to the figure 1.
  • the clamp 12 is loosened and the carriage, carrying this clamp 2, is moved backwards. Then, the strip 9 is slightly separated from the tube 7, as shown in Figure 4. Simultaneously, the strip 9 can be moved back (in the case of a strip 9 movable also longitudinally), so as to be returned to a position of reference, perfectly defined.
  • the bent tube 7 is entirely released in its part forming an elbow 7a, and also over its entire part 7b situated behind the elbow 7a.
  • the tube 7 remains pinched between the jaw 5 and the part 6 of the forming roller 1, in its part 7c situated in front of its elbow 7a, the jaw 5 being at no time loose.
  • the release of the elbow 7a from the tube 7 then allows it to complete its elastic return which was previously limited to the value of the angle B; this means that the direction of the part 7b of the tube 7, located behind the elbow 7a can deviate slightly from the axis 8.
  • the next phase involves a detection element, placed in a determined position behind the bending zone.
  • the detection element is a photoelectric cell 13, carried by the rear end of the strip 9.
  • This last phase consists in rotating the forming roller 1 and the bending arm 4, in the same direction as during bending, therefore in the direction of the arrow F, the rotation of the arm 4 being accompanied by a rotation of the 'assembly of the bent tube 7 around the axis 2, without the elbow 7a of this tube 7 is deformed.
  • the rotation is automatically stopped when the rear part 7b of the tube 7 cuts the light beam from the photoelectric cell 13, this part 7b then forming an angle C with the direction of the axis 8 - see FIG. 5.
  • the angular position of the forming roller 1 and the bending arm 4 is "read" automatically, by means of an encoder provided on the bending machine. It is understood that this angular position is a variable which depends on the position taken by the tube 7 after release of its elbow 7a, therefore a variable depending on the angular difference E defined above. Consequently, a calculation makes it possible to determine then, from the angular position of the forming roller 1, an indication of the effective value of the elastic return of the tube 7.
  • the method is thus applicable to the initial adjustment of a machine for bending tubes, before the execution of a series of all identical bends, with the advantage that the first tube, used for focusing, is neither lost, or even marked by a loosening of the jaw 5 which would be followed by a tightening.
  • This process can also be used to carry out a "sampling" check during the execution of a series of bends.
  • the implementation of the method can be done on automatic machines for bending tubes, new or existing, the addition of the detection element (cell 13) on an existing machine constituting only a very limited transformation, easily achievable .
  • the speed and automatism of the process make it possible, in certain cases, to apply this process not only for an initial adjustment of the machine but also for a control during the execution of each elbow. This is particularly the case for the bending of heterogeneous tubes, for example with differences in hardness, weld beads, a non-constant thickness or outside diameter.
  • the invention is not necessarily linked to the presence of the clamp 12 and the carriage carrying this clamp, and it can also be applied to a bending machine without a carriage.
  • the method of the invention is not limited to the bending of the tubes, and it also relates to any elongated element, such as a bar or profile, bent by similar means and also subject to the phenomenon of elastic return.

Abstract

The invention relates to the monitoring of the spring-back of a tube (7), or other deformable elongate element, on it being bent by wrapping around a forming component (1), with clamping of the tube (in 5) at a portion (7c) located in front of the bend to be formed. <??>After producing the bend (7a), the portion (7c) of the tube located in front of this bend remains clamped, while its portion (7b) located to the rear of the bend (7a) is released. The extent of the spring- back is determined by a detection means (13) which carries out a measurement or a referencing on the released portion (7b) of the tube located to the rear of the bend (7a). The detection of the spring-back is made on rotation of the tube (7) and of the forming component (1) about the axis (2) of the bend (7a) by detecting the instant when the portion (7b) reaches a predetermined position. <??>This process enables the bending of the tube (7) to be resumed after detecting the spring-back. <IMAGE>

Description

La présente invention concerne un procédé pour le contrôle du retour élastique, lors d'une opération de cintrage d'un élément allongé déformable. L'invention a aussi pour objet un dispositif, associé à un outillage de cintrage, qui est destiné à la mise en oeuvre de ce procédé de contrôle. Cette invention s'applique plus particulièrement, mais non exclusivement, au contrôle du retour élastique des tubes, sur les machines automatiques à cintrer les tubes.The present invention relates to a method for controlling the elastic return, during a bending operation of a deformable elongated element. The invention also relates to a device, associated with a bending tool, which is intended for the implementation of this control method. This invention applies more particularly, but not exclusively, to the control of the elastic return of the tubes, on automatic machines for bending the tubes.

Le cintrage des tubes, visant à former sur ces tubes des coudes caractérisés par leur rayon et leur angle, est réalisé au moyen d'outillages comprenant habituellement : un galet formeur rotatif autour d'un axe orthogonal à la direction initiale du tube à cintrer, présentant à sa périphérie une gorge annulaire et supportant, ou formant par lui-même, un premier mors - un second mors porté par un bras de cintrage monté tournant autour de l'axe du galet formeur, le second mors étant mobile sur le bras et coopérant avec le premier mors pour enserrer et entraîner le tube à cintrer - une réglette parallèle à la direction initiale du tube, située en arrière des mors et prévue pour être appliquée latéralement contre le tube à cintrer.The bending of the tubes, aimed at forming on these tubes bends characterized by their radius and their angle, is carried out by means of tools usually comprising: a forming roller rotating around an axis orthogonal to the initial direction of the tube to be bent, having at its periphery an annular groove and supporting, or forming by itself, a first jaw - a second jaw carried by a bending arm mounted rotating around the axis of the forming roller, the second jaw being movable on the arm and cooperating with the first jaw to grip and drive the tube to be bent - a strip parallel to the initial direction of the tube, located behind the jaws and intended to be applied laterally against the tube to be bent.

Ainsi, pour réaliser un coude sur une partie du tube à cintrer, cette partie est serrée entre les deux mors et entraînée en avant par la commande de rotation du bras de cintrage, de manière à s'enrouler dans la gorge du galet formeur, tandis que la réglette, appliquée latéralement contre le tube en arrière de la partie en cours de cintrage, évite toute déformation non désirée du tube au-delà de la partie à cintrer, et assure la réaction aux efforts de cintrage.Thus, to produce an elbow on a part of the tube to be bent, this part is clamped between the two jaws and driven forward by the control of rotation of the bending arm, so as to wind in the groove of the forming roller, while that the strip, applied laterally against the tube behind the part being bent, avoids any unwanted deformation of the tube beyond the part to be bent, and ensures the reaction to bending forces.

Les caractéristiques dimensionnelles du galet formeur déterminent le rayon du coude ainsi formé sur le tube, tandis que l'angle de rotation du bras de cintrage détermine l'angle du coude. Toutefois, en raison du phénomène dit de "retour élastique", l'angle définitif du coude est toujours inférieur à l'angle de la rotation commandée du bras de cintrage.The dimensional characteristics of the forming roller determine the radius of the bend thus formed on the tube, while the angle of rotation of the bending arm determines the angle of the bend. However, due to the phenomenon known as "elastic return", the final angle of the elbow is always less than the angle of the controlled rotation of the bending arm.

Il résulte de ce qui précède que, pour cintrer un tube à une valeur d'angle bien précise, il convient de faire décrire au bras de cintrage une rotation selon un angle égal à cette valeur, augmentée du retour élastique. Ceci suppose que l'on puisse connaître ou déterminer le retour élastique pour le prendre en compte. Ce retour élastique peut certes être déterminé de façon théorique, mais il importe de pouvoir aussi contrôler sa valeur réelle, dans la pratique. Un tel besoin existe, notamment, lorsqu'il s'agit d'effectuer le réglage d'une machine à cintrer automatique, avant d'exécuter sur la machine une série de coudes tous identiques.It follows from the above that, to bend a tube at a very precise angle value, it is necessary to have the bending arm describe a rotation at an angle equal to this value, increased by the elastic return. This supposes that one can know or determine the elastic return to take it into account. This elastic return can certainly be determined from theoretically, but it is also important to be able to control its real value in practice. There is such a need, in particular, when it comes to adjusting an automatic bending machine, before executing on the machine a series of all identical bends.

Un procédé connu, pour le contrôle du retour élastique, consiste à détecter l'ampleur de ce retour élastique sur la machine à cintrer, au moyen de palpeurs mécaniques. La mise en oeuvre de ce procédé connu nécessite une ouverture des mors, libérant le tube dans sa partie qui vient d'être cintrée, les palpeurs venant en contact avec la région du tube située en avant du coude formé.A known method for controlling the elastic return consists in detecting the extent of this elastic return on the bending machine, by means of mechanical probes. The implementation of this known method requires an opening of the jaws, releasing the tube in its part which has just been bent, the feelers coming into contact with the region of the tube situated in front of the bend formed.

L'inconvénient principal du procédé existant, résumé ci-dessus, réside dans le fait qu'après détection du retour élastique, il est pratiquement impossible de reprendre le cintrage du tube, en tenant compte de ce retour élastique, pour amener exactement le coude à la valeur d'angle désirée. En effet, le tube devrait être de nouveau serré entre les deux mors précédemment ouverts. Or il est impossible de venir pincer de nouveau le tube d'une manière identique au cintrage précédent. Il en résulte un marquage du tube par les mors, qui rend ce tube inutilisable par la suite. Ainsi, le tube servant au contrôle du retour élastique est un tube perdu, ce qui est difficilement acceptable dans le cas de tubes coûteux en raison de leurs dimensions et/ou de leur matière.The main drawback of the existing process, summarized above, lies in the fact that after detection of the elastic return, it is practically impossible to resume bending the tube, taking account of this elastic return, to bring the elbow exactly to the desired angle value. Indeed, the tube should be clamped again between the two previously opened jaws. However, it is impossible to pinch the tube again in a manner identical to the previous bending. This results in a marking of the tube by the jaws, which makes this tube unusable subsequently. Thus, the tube used to control the elastic return is a lost tube, which is difficult to accept in the case of expensive tubes due to their dimensions and / or their material.

Par ailleurs, les palpeurs actuellement utilisés pour le contrôle du retour élastique constituent sur les machines à cintrer des dispositifs supplémentaires encombrants et gênants, situés dans la zone de cintrage.Furthermore, the probes currently used for controlling the elastic return constitute on the bending machines additional bulky and annoying devices, located in the bending zone.

On connaît aussi, par le document DD-A-109331 (brevet est-allemand), un autre procédé pour le contrôle du retour élastique d'un tube dans lequel, après exécution du coude, la partie du tube située en avant de ce coude reste serrée, tandis que la partie dudit tube située en arrière du coude est libérée, et dans lequel une mesure ou un repérage, déterminant l'ampleur du retour élastique, est effectué sur la partie dudit tube située en arrière du coude.Also known, from document DD-A-109331 (East German patent), another method for controlling the elastic return of a tube in which, after execution of the elbow, the part of the tube situated in front of this elbow remains tight, while the part of said tube located behind the elbow is released, and in which a measurement or a location, determining the extent of the elastic return, is carried out on the part of said tube located behind the elbow.

Ainsi, après le cintrage, le retour élastique du tube s'effectue librement, tandis que ce tube reste serré entre les mors de l'outillage de cintrage. La détection du retour élastique est faite dans la partie libérée du tube, située en arrière du coude, à distance de la zone de cintrage. Le cintrage peut être repris ensuite, en tenant compte du retour élastique, sans interrompre à aucun moment le serrage du tube dans sa partie située en avant du coude donc sans marquer le tube ; le tube utilisé pour le contrôle du retour élastique n'est donc jamais perdu, et par conséquent le principe d'un tel procéde se révèle avantageux.Thus, after bending, the elastic return of the tube takes place freely, while this tube remains clamped between the jaws of the bending tool. The detection of the elastic return is made in the released part of the tube, located behind the elbow, away from the bending zone. The bending can then be resumed, taking into account the elastic return, without at any time interrupting the tightening of the tube in its part located in before the elbow therefore without marking the tube; the tube used for controlling the elastic return is therefore never lost, and therefore the principle of such a procedure proves to be advantageous.

Toutefois, le document DD-A-109331 propose uniquement, pour la mesure ou le repérage du retour élastique du tube, un dispositif comprenant une pièce pourvue d'une échelle angulaire, montée sur la partie libérée du tube, et un système optique de visée monté sur le bâti de la machine à cintrer.However, document DD-A-109331 only proposes, for measuring or locating the elastic return of the tube, a device comprising a part provided with an angular scale, mounted on the released part of the tube, and an optical sighting system. mounted on the frame of the bending machine.

Un tel dispositif forme donc une sorte d'instrument de mesure extérieur, et sa mise en oeuvre nécessite l'adjonction d'éléments complémentaires sur la machine et sur le tube à cintrer, ce qui constitue un premier inconvénient.Such a device therefore forms a kind of external measuring instrument, and its implementation requires the addition of complementary elements on the machine and on the tube to be bent, which constitutes a first drawback.

De plus, l'utilisation pratique d'un tel dispositif de mesure du retour élastique nécessite une double intervention humaine, d'une part pour procéder à la visée et à la lecture de graduation au moyen du système optique, et d'autre part pour commander une action correctrice sur la machine en fonction de la lecture réalisée à l'aide du système de visée.In addition, the practical use of such an elastic return measurement device requires a double human intervention, on the one hand to carry out the aiming and reading of graduation by means of the optical system, and on the other hand to order corrective action on the machine based on the reading taken using the sighting system.

Ainsi, l'utilisation de ce dispositif demande un temps important, et le processus de détermination du retour élastique et de correction en fonction de la valeur de ce retour élastique ne peut être automatisé.Thus, the use of this device requires significant time, and the process of determining the elastic return and of correction as a function of the value of this elastic return cannot be automated.

Le but de la présente invention est de permettre une mesure et une correction rapides et automatiques du retour élastique, sans adjonction d'éléments de mesure extérieurs notamment sur le tube et aussi en supprimant les interventions humaines telles que visée et lecture d'une graduation, ceci par des moyens simples et particulièrement adaptés aux machines à cintrer avec commande numérique, actuellement très courantes, disposant de moyens de calcul.The aim of the present invention is to allow rapid and automatic measurement and correction of the elastic return, without the addition of external measurement elements, in particular on the tube, and also by eliminating human intervention such as aiming and reading a graduation, this by simple means and particularly suitable for bending machines with numerical control, currently very common, having means of calculation.

A cet effet, l'invention concerne un procédé pour le contrôle du retour élastique, lors du cintrage d'un élément allongé déformable tel que tube par enroulement de cet élément autour d'un organe formeur, avec serrage de cet élément dans une partie situee en avant d'un coude à former, le procédé prévoyant de façon connue qu'après exécution du coude, la partie de l'élément allongé tel que tube située en avant de ce coude reste serrée, tandis que la partie dudit élément située en arrière du coude est libérée, et qu'une mesure ou un repérage, déterminant l'ampleur du retour élastique, est effectué sur la partie libérée dudit élément située en arrière du coude, et ce procédé étant caractérisé en ce que la détection du retour élastique est effectuée, après libération de l'élément allongé tel que tube dans sa partie située en arrière du coude, en faisant décrire à cet élément ainsi qu'à l'organe formeur une rotation autour de l'axe du coude, et en détectant l'instant où la partie dudit élément située en arrière du coude atteint une position déterminée, ainsi que la position angulaire de l'organe formeur à cet instant ; connaissant alors la position angulaire de l'organe formeur, un calcul simple permet d'obtenir la valeur du retour élastique, ce calcul étant effectué de façon automatique.To this end, the invention relates to a method for controlling the elastic return, when bending an elongate deformable element such as a tube by winding this element around a forming member, with clamping of this element in a situated part. in front of an elbow to be formed, the method providing in known manner that after execution of the elbow, the part of the elongated element such as a tube situated in front of this elbow remains tight, while the part of said element situated in the rear of the elbow is released, and that a measurement or a marking, determining the extent of the elastic return, is carried out on the released part of said element located behind the elbow, and this method being characterized in that the detection of the elastic return is carried out, after release of the elongated element such as tube in its part situated behind the elbow, by making this element and the forming member describe a rotation around the axis of the elbow, and by detecting the instant when the part of said element situated behind the elbow reaches a determined position, as well as the angular position of the forming member at this instant; then knowing the angular position of the forming member, a simple calculation makes it possible to obtain the value of the elastic return, this calculation being carried out automatically.

La partie de l'élément allongé tel que tube, située en arrière du coude, peut être notamment libérée après exécution du coude par desserrage de la pince maintenant ledit élément et par écartement de la réglette appliquée latéralement contre cet élément lors du cintrage, dans le cas d'une machine à cintrer pourvue d'une pince et d'une réglette.The part of the elongated element such as a tube, situated behind the elbow, can in particular be released after the elbow has been executed by loosening the clamp holding said element and by spacing the strip applied laterally against this element during bending, in the case of a bending machine provided with a clamp and a strip.

Avantageusement, la libération de la partie de l'élément allongé tel que tube, située en arrière du coude, est effectuée seulement après que l'organe formeur a décrit une rotation de sens inverse à celui du cintrage précédemment réalisé, et de valeur égale à l'angle théorique de retour élastique, diminué d'un petit écart angulaire.Advantageously, the release of the part of the elongated element such as a tube, situated behind the elbow, is carried out only after the forming member has described a rotation in the opposite direction to that of the bending previously carried out, and of value equal to the theoretical elastic return angle, reduced by a small angular difference.

Le dispositif selon l'invention associé à un outillage de cintrage, et destiné à la mise en oeuvre du procédé défini ci-dessus, comprend de façon connue un moyen de détection disposé en arrière de l'outillage de cintrage, et apte à détecter au moins une position de la partie de l'élément cintré située en arrière du coude, après libération de cette partie, le moyen de détection étant prévu pour détecter l'instant de passage de la partie de l'élément cintré, située en arrière du coude, dans une position déterminée, ceci au cours de la rotation de cet élément et de l'organe formeur, la position angulaire de l'organe formeur à l'instant de cette détection fournissant une indication de l'ampleur du retour élastique.The device according to the invention associated with a bending tool, and intended for the implementation of the method defined above, comprises in known manner a detection means disposed behind the bending tool, and capable of detecting at minus a position of the part of the curved element situated behind the elbow, after release of this part, the detection means being provided for detecting the instant of passage of the part of the curved element, situated behind the elbow , in a determined position, this during the rotation of this element and of the forming member, the angular position of the forming member at the time of this detection providing an indication of the extent of the elastic return.

Le moyen de détection est, par exemple, une cellule photoélectrique détectant l'instant où la partie de l'élément cintré située en arrière du coude coupe un rayon lumineux au cours de sa rotation.The detection means is, for example, a photoelectric cell detecting the instant when the part of the curved element located behind the elbow intersects a light ray during its rotation.

Dans une forme de réalisation particulière du dispositif objet de l'invention, le moyen de détection est porté par la réglette appartenant à l'outillage de cintrage, appliquée latéralement contre l'élément allongé tel que tube à cintrer, cette réglette étant écartée dudit élément et placée dans une position déterminée, pour libérer la partie de l'élément considéré située en arrière du coude. De préférence, le moyen de détection est porté par l'extrémité arrière de la réglette. Le dispositif possède ainsi un encombrement minimal, et il se situe à l'écart de la zone de cintrage ; bien que porté par un organe mobile, à savoir la réglette, ce dispositif occupe une position fixe, parfaitement définie, au moment où il intervient pour déterminer l'ampleur du retour élastique du tube, ou autre élément allongé.In a particular embodiment of the device which is the subject of the invention, the detection means is carried by the strip belonging to the bending tool, applied laterally against the elongated element such as a tube to be bent, this strip being spaced from said element and placed in a determined position, to release the part of the element under consideration located behind the elbow. Preferably, the detection means is carried by the rear end of the strip. The device thus has a minimal bulk, and it is located away from the bending zone; although carried by a movable member, namely the slide, this device occupies a fixed position, perfectly defined, when it intervenes to determine the extent of the elastic return of the tube, or other elongated element.

De toute façon, l'invention sera mieux comprise à l'aide de la description qui suit, en référence au dessin schématique annexé illustrant, à titre d'exemple non limitatif, un mode de mise en oeuvre de ce procédé pour le contrôle du retour élastique, lors du cintrage d'un élément allongé.In any case, the invention will be better understood with the aid of the description which follows, with reference to the appended schematic drawing illustrating, by way of nonlimiting example, an embodiment of this method for controlling the return. elastic, when bending an elongated element.

Les figures 1 à 5 du dessin montrent très schématiquement l'outillage de cintrage d'une machine à cintrer les tubes, et elles illustrent les phases successives d'un processus de contrôle du retour élastique d'un tube, conforme à la présente invention.Figures 1 to 5 of the drawing very schematically show the bending tool of a tube bending machine, and they illustrate the successive phases of a process for controlling the elastic return of a tube, in accordance with the present invention.

Plus particulièrement, ces figures montrent un outillage comprenant un galet formeur 1, monté tournant autour de son axe 2 et présentant, à sa périphérie, une gorge 3 au moins partiellement annulaire. Autour de l'axe 2 est aussi monté tournant un bras de cintrage 4, qui porte un mors 5 mobile en direction radiale. Le mors 5 coopère avec une partie 6 du galet formeur 1, située en vis-à-vis, pour serrer un tube à cintrer 7 qui est initialement rectiligne, l'axe initial du tube 7 étant indiqué en 8.More particularly, these figures show a tool comprising a forming roller 1, mounted rotating around its axis 2 and having, at its periphery, a groove 3 at least partially annular. Around the axis 2 is also mounted rotating a bending arm 4, which carries a jaw 5 movable in the radial direction. The jaw 5 cooperates with a part 6 of the forming roller 1, located opposite, to clamp a bending tube 7 which is initially rectilinear, the initial axis of the tube 7 being indicated at 8.

L'outillage de cintrage comprend encore une réglette 9, s'étendant parallèlement à l'axe 8 du tube à cintrer 7, et présentant elle-même une gorge longitudinale 10. La réglette 9 est déplaçable transversalement, comme indiqué par une flèche 11, pour pouvoir être soit appliquée latéralement contre le tube 7, en arrière de la partie à cintrer, soit écartée du tube 7. De plus, cette réglette 9 peut être déplacée longitudinalement, donc parallèlement à l'axe 8, pour accompagner le tube 7 dans son mouvement d'avance décrit au cours du cintrage.The bending tool further comprises a strip 9, extending parallel to the axis 8 of the tube to be bent 7, and itself having a longitudinal groove 10. The strip 9 is movable transversely, as indicated by an arrow 11, to be able to be applied laterally against the tube 7, behind the part to be bent, or separated from the tube 7. In addition, this strip 9 can be moved longitudinally, therefore parallel to the axis 8, to accompany the tube 7 in its advance movement described during bending.

Le tube à cintrer 7 est maintenu, en arrière de sa partie à cintrer, au moyen d'une pince 12 portée par un chariot non représenté, déplaçable dans la direction de l'axe 8. Le déplacement du chariot pourvu de la pince 12 permet d'amener, au niveau de l'outillage précédemment décrit, la partie du tube 7 qui doit être cintrée.The bending tube 7 is held, behind its bending part, by means of a clamp 12 carried by a carriage not shown, movable in the direction of the axis 8. The movement of the carriage provided with the clamp 12 allows to bring, at the level of the tool previously described, the part of the tube 7 which must be bent.

Pour procéder au cintrage du tube 7, on serre ce tube 7 entre le mors mobile 5 et la partie 6 du galet formeur 1, on applique aussi la réglette 9 contre le tube 7, et l'on fait tourner le bras de cintrage 4 d'un certain angle A autour de l'axe 2, dans le sens de la flèche F, comme le montre la figure 1 qui indique la position d'arrêt du bras 4 en fin de cintrage.To bend the tube 7, this tube 7 is clamped between the movable jaw 5 and the part 6 of the forming roller 1, the strip 9 is also applied against the tube 7, and the bending arm 4 d is rotated '' a certain angle A around axis 2, in the direction of arrow F, as shown in Figure 1 which indicates the stop position of the arm 4 at the end of bending.

Lors d'un processus de contrôle du retour élastique du tube 7, on cintre d'abord le tube 7 à une valeur connue, par rotation commandée du bras de cintrage 4, selon l'angle A, comme décrit précédemment en référence à la figure 1.During a process of controlling the elastic return of the tube 7, the tube 7 is first bent to a known value, by controlled rotation of the bending arm 4, according to the angle A, as described previously with reference to the figure 1.

Ensuite, on commande une rotation du bras de cintrage 4 autour de l'axe 2, dans le sens inverse de celui de la flèche F et selon un angle B, dont la valeur est égale à l'angle théorique de retour élastique du tube 7, diminué d'un petit écart E - voir figure 2.Then, a rotation of the bending arm 4 is controlled around the axis 2, in the opposite direction to that of the arrow F and at an angle B, the value of which is equal to the theoretical angle of elastic return of the tube 7 , minus a small deviation E - see Figure 2.

Jusqu'à ce stade, le tube 7 reste serré par la pince 12, et la réglette 9 reste appliquée contre ce tube 7.Up to this stage, the tube 7 remains clamped by the clamp 12, and the strip 9 remains applied against this tube 7.

Dans la phase suivante, illustrée par la figure 3, la pince 12 est desserrée et le chariot, portant cette pince 2, est déplacé vers l'arrière. Ensuite, la réglette 9 est légèrement écartée du tube 7, comme le montre la figure 4. Simultanément, la réglette 9 peut être reculée (dans le cas d'une réglette 9 déplaçable aussi longitudinalement), de manière a se trouver ramenée dans une position de référence, parfaitement définie.In the following phase, illustrated by FIG. 3, the clamp 12 is loosened and the carriage, carrying this clamp 2, is moved backwards. Then, the strip 9 is slightly separated from the tube 7, as shown in Figure 4. Simultaneously, the strip 9 can be moved back (in the case of a strip 9 movable also longitudinally), so as to be returned to a position of reference, perfectly defined.

A ce stade, le tube 7 cintré est entièrement libéré dans sa partie formant un coude 7a, et aussi sur toute sa partie 7b située en arrière du coude 7a. Par contre, le tube 7 reste pincé entre le mors 5 et la partie 6 du galet formeur 1, dans sa partie 7c située en avant de son coude 7a, le mors 5 n'étant à aucun moment desserré. La libération du coude 7a du tube 7 lui permet alors d'achever son retour élastique qui était précédemment limité à la valeur de l'angle B ; ceci signifie que la direction de la partie 7b du tube 7, située en arrière du coude 7a peut s'écarter légèrement de l'axe 8.At this stage, the bent tube 7 is entirely released in its part forming an elbow 7a, and also over its entire part 7b situated behind the elbow 7a. On the other hand, the tube 7 remains pinched between the jaw 5 and the part 6 of the forming roller 1, in its part 7c situated in front of its elbow 7a, the jaw 5 being at no time loose. The release of the elbow 7a from the tube 7 then allows it to complete its elastic return which was previously limited to the value of the angle B; this means that the direction of the part 7b of the tube 7, located behind the elbow 7a can deviate slightly from the axis 8.

La phase suivante fait intervenir un élément de détection, placé dans une position déterminée en arrière de la zone de cintrage. Dans l'exemple représenté, l'élément de détection est une cellule photoélectrique 13, portée par l'extrémité arrière de la réglette 9.The next phase involves a detection element, placed in a determined position behind the bending zone. In the example shown, the detection element is a photoelectric cell 13, carried by the rear end of the strip 9.

Cette dernière phase consiste à entraîner en rotation le galet formeur 1 et le bras de cintrage 4, dans le même sens que lors du cintrage donc dans le sens de la flèche F, la rotation du bras 4 s'accompagnant d'une rotation de l'ensemble du tube cintré 7 autour de l'axe 2, sans que le coude 7a de ce tube 7 soit déformé. La rotation est arrêtée automatiquement lorsque la partie arrière 7b du tube 7 coupe le faisceau lumineux de la cellule photoélectrique 13, cette partie 7b formant alors un angle C avec la direction de l'axe 8 - voir figure 5.This last phase consists in rotating the forming roller 1 and the bending arm 4, in the same direction as during bending, therefore in the direction of the arrow F, the rotation of the arm 4 being accompanied by a rotation of the 'assembly of the bent tube 7 around the axis 2, without the elbow 7a of this tube 7 is deformed. The rotation is automatically stopped when the rear part 7b of the tube 7 cuts the light beam from the photoelectric cell 13, this part 7b then forming an angle C with the direction of the axis 8 - see FIG. 5.

A ce moment, la position angulaire du galet formeur 1 et du bras de cintrage 4 est "lue" automatiquement, au moyen d'un codeur prévu sur la machine à cintrer. On comprend que cette position angulaire est une variable qui dépend de la position prise par le tube 7 après libération de son coude 7a, donc une variable dépendant de l'écart angulaire E défini plus haut. Par conséquent, un calcul permet de déterminer alors, à partir de la position angulaire du galet formeur 1, une indication de la valeur effective du retour élastique du tube 7.At this time, the angular position of the forming roller 1 and the bending arm 4 is "read" automatically, by means of an encoder provided on the bending machine. It is understood that this angular position is a variable which depends on the position taken by the tube 7 after release of its elbow 7a, therefore a variable depending on the angular difference E defined above. Consequently, a calculation makes it possible to determine then, from the angular position of the forming roller 1, an indication of the effective value of the elastic return of the tube 7.

L'intérêt principal du procédé réside dans le fait que cette valeur réelle du retour élastique est déterminée en maintenant le tube 7 toujours serré, au même point, entre le mors 5 et la partie 6 du galet formeur 1. Il devient ainsi possible de reprendre le même coude 7a, pour l'amener à la valeur exacte désirée : à cet effet, la réglette 9 est à nouveau appliquée latéralement contre le tube 7, et le bras de cintrage 4 est actionné une nouvelle fois dans le sens du cintrage, en décrivant une rotation d'un angle égal à la valeur, précédemment déterminée, du retour élastique.The main interest of the process lies in the fact that this real value of the elastic return is determined by keeping the tube 7 always tightened, at the same point, between the jaw 5 and the part 6 of the forming roller 1. It thus becomes possible to resume the same bend 7a, to bring it to the exact desired value: for this purpose, the strip 9 is again applied laterally against the tube 7, and the bending arm 4 is actuated again in the direction of bending, describing a rotation of an angle equal to the value, previously determined, of the elastic return.

Le même processus peut être répété, de façon itérative, jusqu'à obtention très précise de l'angle de cintrage désiré.The same process can be repeated iteratively until the desired bending angle is very precise.

Le procédé est ainsi applicable au réglage initial d'une machine à cintrer les tubes, avant l'exécution d'une série de coudes tous identiques, avec l'avantage que le premier tube, utilisé pour la mise au point, n'est ni perdu, ni même marqué par un desserrage du mors 5 qui serait suivi d'un resserrage. Ce procédé peut aussi être utilisé pour effectuer un contrôle "par prélèvement", au cours de l'exécution d'une série de coudes.The method is thus applicable to the initial adjustment of a machine for bending tubes, before the execution of a series of all identical bends, with the advantage that the first tube, used for focusing, is neither lost, or even marked by a loosening of the jaw 5 which would be followed by a tightening. This process can also be used to carry out a "sampling" check during the execution of a series of bends.

La mise en oeuvre du procédé peut se faire sur des machines automatiques à cintrer les tubes, nouvelles ou existantes, l'adjonction de l'élément de détection (cellule 13) sur une machine existante ne constituant qu'une transformation très limitée, facilement réalisable.The implementation of the method can be done on automatic machines for bending tubes, new or existing, the addition of the detection element (cell 13) on an existing machine constituting only a very limited transformation, easily achievable .

De plus, la rapidité et l'automatisme du procédé permettent, dans certains cas, d'appliquer ce procédé non seulement pour un réglage initial de la machine mais aussi pour un contrôle lors de l'exécution de chaque coude. C'est notamment le cas pour le cintrage des tubes hétérogènes, par exemple avec des différences de dureté, des cordons de soudure, une épaisseur ou un diamètre extérieur non constants.In addition, the speed and automatism of the process make it possible, in certain cases, to apply this process not only for an initial adjustment of the machine but also for a control during the execution of each elbow. This is particularly the case for the bending of heterogeneous tubes, for example with differences in hardness, weld beads, a non-constant thickness or outside diameter.

Il est à noter qu'on ne s'éloignerait pas du cadre de l'invention en remplaçant la cellule photoélectrique 13 par tout moyen de détection équivalent, tel qu'un détecteur mécanique actionnant un contact électrique, le moyen de détection étant associé à la réglette 9 ou indépendant de cette réglette. Par ailleurs, l'invention n'est pas liée obligatoirement à la présence de la pince 12 et du chariot portant cette pince, et elle peut être aussi appliquée à une machine à cintrer dépourvue de chariot. Enfin, le procédé de l'invention n'est pas limité au cintrage des tubes, et il concerne aussi tout élément allongé, tel que barre ou profilé, cintré par des moyens analogues et également sujet au phénomène du retour élastique.It should be noted that it would not depart from the scope of the invention by replacing the photoelectric cell 13 by any equivalent detection means, such as a mechanical detector actuating an electrical contact, the detection means being associated with the strip 9 or independent of this strip. Furthermore, the invention is not necessarily linked to the presence of the clamp 12 and the carriage carrying this clamp, and it can also be applied to a bending machine without a carriage. Finally, the method of the invention is not limited to the bending of the tubes, and it also relates to any elongated element, such as a bar or profile, bent by similar means and also subject to the phenomenon of elastic return.

Claims (8)

1. Procédé pour le contrôle du retour élastique, lors du cintrage d'un élément allongé déformable tel que tube (7) par enroulement de cet élément autour d'un organe formeur (1), avec serrage de cet élément (en 5) dans une partie (7c) située en avant d'un coude (7a) à former, ce procédé prévoyant qu'après exécution du coude (7a), la partie (7c) de l'élément allongé tel que tube (7) située en avant de ce coude (7a) reste serrée, tandis que la partie (7b) dudit élément (7) située en arrière du coude (7a) est libérée, et qu'une mesure ou un repérage, déterminant l'ampleur du retour élastique, est effectué sur la partie libérée (7b) dudit élément (7) située en arrière du coude (7a), caractérisé en ce que la détection du retour élastique est effectuée, après libération de l'élément allongé tel que tube (7) dans sa partie (7b) située en arrière du coude (7a), en faisant décrire à cet élément (7) ainsi qu'à l'organe formeur (1) une rotation autour de l'axe (2) du coude (7a), et en détectant l'instant où la partie (7b) dudit élément (7) située en arrière du coude (7a) atteint une position déterminée, ainsi que la position angulaire de l'organe formeur (1) à cet instant.1. Method for controlling the elastic return, when bending an elongate deformable element such as a tube (7) by winding this element around a forming member (1), with clamping of this element (at 5) in a part (7c) located in front of an elbow (7a) to be formed, this method providing that after execution of the elbow (7a), the part (7c) of the elongated element such as tube (7) located in front of this elbow (7a) remains tight, while the part (7b) of said element (7) located behind the elbow (7a) is released, and that a measurement or a location, determining the extent of the elastic return, is carried out on the released part (7b) of said element (7) located behind the elbow (7a), characterized in that the detection of the elastic return is carried out, after release of the elongated element such as tube (7) in its part (7b) located behind the elbow (7a), making this element (7) and the forming member (1) describe a rotation around the axis (2) of the elbow (7a), and detecting the instant when the part (7b) of said element (7) located behind the elbow (7a) reaches a determined position, as well as the angular position of the forming member (1) at this instant. 2. Procédé selon la revendication 1, caractérisé en ce que la partie (7b) de l'élément allongé tel que tube (7), située en arrière du coude (7a), est libérée après exécution du coude (7a) par desserrage d'une pince (12) maintenant ledit élément (7) et par écartement d'une réglette (9) appliquée latéralement contre cet élément (7) lors du cintrage.2. Method according to claim 1, characterized in that the part (7b) of the elongated element such as tube (7), located behind the elbow (7a), is released after execution of the elbow (7a) by loosening d 'a clamp (12) holding said element (7) and by spacing a strip (9) applied laterally against this element (7) during bending. 3. Procédé selon la revendication 1 ou 2, caractérisé en ce que la libération de la partie (7b) de l'élément allongé tel que tube (7), située en arrière du coude (7a), est effectuée seulement après que l'organe formeur (1) a décrit une rotation de sens inverse à celui du cintrage précédemment réalisé (F), et de valeur (B) égale à l'angle théorique de retour élastique, diminué d'un petit écart angulaire (E).3. Method according to claim 1 or 2, characterized in that the release of the part (7b) of the elongated element such as tube (7), located behind the elbow (7a), is carried out only after the forming member (1) has described a rotation in the opposite direction to that of the bending previously carried out (F), and of value (B) equal to the theoretical angle of elastic return, reduced by a small angular deviation (E). 4. Procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce que, après détermination de l'ampleur du retour élastique, le cintrage de l'élément allongé tel que tube (7) est repris en tenant compte du retour élastique, sans interrompre à aucun moment le serrage de cet élément (7) dans sa partie (7c) située en avant du coude (7a).4. Method according to any one of claims 1 to 3, characterized in that, after determining the extent of the elastic return, the bending of the elongated element such as tube (7) is resumed taking into account the elastic return , without interrupting at any time the tightening of this element (7) in its part (7c) located in front of the elbow (7a). 5. Dispositif pour le contrôle du retour élastique, lors du cintrage d'un élément allongé tel que tube (7), pour la mise en oeuvre du procédé selon l'une quelconque des revendications 1 à 4, ce dispositif étant associé à un outillage de cintrage (1,4,5,9) et comprenant essentiellement un moyen de détection (13) disposé en arrière de l'outillage de cintrage (1,4,5,9) et apte à détecter au moins une position de la partie (7b) de l'élément cintré (7) située en arrière du coude (7a), après libération de cette partie (7b), caractérisé en ce que le moyen de détection (13) est prévu pour détecter l'instant de passage de la partie (7b) de l'élément cintré (7), située en arrière du coude (7a), dans une position déterminée, ceci au cours de la rotation de cet élément (7) et de l'organe formeur (1), la position angulaire de l'organe formeur (1) à l'instant de cette détection fournissant une indication de l'ampleur du retour élastique.5. Device for controlling the elastic return, during the bending of an elongated element such as a tube (7), for implementing the method according to any one of claims 1 to 4, this device being associated with a tool bending (1,4,5,9) and essentially comprising a means of detection (13) disposed behind the bending tool (1,4,5,9) and capable of detecting at least one position of the part (7b) of the curved element (7) located behind the elbow ( 7a), after release of this part (7b), characterized in that the detection means (13) is provided for detecting the instant of passage of the part (7b) of the curved element (7), located behind of the elbow (7a), in a determined position, this during the rotation of this element (7) and of the forming member (1), the angular position of the forming member (1) at the instant of this detection providing an indication of the extent of elastic return. 6. Dispositif selon la revendication 5, caractérisé en ce que le moyen de détection est une cellule photoélectrique (13), détectant l'instant où la partie (7b) de l'élément cintré (7) située en arrière du coude (7a) coupe un rayon lumineux au cours de sa rotation.6. Device according to claim 5, characterized in that the detection means is a photoelectric cell (13), detecting the moment when the part (7b) of the curved element (7) located behind the elbow (7a) cuts a ray of light during its rotation. 7. Dispositif selon la revendication 5 ou 6, caractérisé en ce que le moyen de détection (13) est porté par une réglette (9) appartenant à l'outillage de cintrage, appliquée latéralement contre l'élément allongé tel que tube (7) lors du cintrage de cet élément allongé (7).7. Device according to claim 5 or 6, characterized in that the detection means (13) is carried by a strip (9) belonging to the bending tool, applied laterally against the elongated element such as tube (7) during the bending of this elongated element (7). 8. Dispositif selon la revendication 7, caractérisé en ce que le moyen de détection (13) est porté par l'extrémité arrière de la réglette (9).8. Device according to claim 7, characterized in that the detection means (13) is carried by the rear end of the strip (9).
EP89420106A 1988-04-21 1989-03-24 Method and device for controlling the resilience by bending of an elongated element such as a tube. Expired - Lifetime EP0338944B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89420106T ATE70473T1 (en) 1988-04-21 1989-03-24 METHOD AND DEVICE FOR CHECKING THE RESILIENCE WHEN BENDING AN LONG PART SUCH AS A PIPE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8805714 1988-04-21
FR8805714A FR2630358B1 (en) 1988-04-21 1988-04-21 PROCESS AND DEVICE FOR CONTROLLING THE ELASTIC RETURN WHEN BENDING AN ELONGATED ELEMENT SUCH AS A TUBE

Publications (2)

Publication Number Publication Date
EP0338944A1 true EP0338944A1 (en) 1989-10-25
EP0338944B1 EP0338944B1 (en) 1991-12-18

Family

ID=9365803

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89420106A Expired - Lifetime EP0338944B1 (en) 1988-04-21 1989-03-24 Method and device for controlling the resilience by bending of an elongated element such as a tube.

Country Status (7)

Country Link
US (1) US4979385A (en)
EP (1) EP0338944B1 (en)
JP (1) JPH01306021A (en)
AT (1) ATE70473T1 (en)
DE (2) DE68900564D1 (en)
ES (1) ES2028465T3 (en)
FR (1) FR2630358B1 (en)

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EP0384477A2 (en) * 1989-02-23 1990-08-29 Rasi Maschinenbau Und -Handels Gmbh Method and machine for bending tubes
EP0461006A1 (en) * 1990-06-08 1991-12-11 ETAT-FRANCAIS représenté par le Délégué Général pour l' Armement Method and apparatus for bending tubes
EP0719603A1 (en) * 1994-12-26 1996-07-03 Toyota Jidosha Kabushiki Kaisha Supplemental bending method for correcting already bent workpiece, and apparatus for determining information for supplemental bending on the workpiece
WO2005016567A1 (en) * 2003-08-05 2005-02-24 Rosenberger Ag Method for determining the elastic recovery value of a workpiece that is bent in a bending machine equipped with at least one bending arm
WO2007121985A1 (en) * 2006-04-24 2007-11-01 Rasi Maschinenbau Gmbh Method for the mechanical tensile bending of bars, more particularly pipes
CN102632118A (en) * 2012-05-08 2012-08-15 古河奇宏电子（苏州）有限公司 Automatic bending device for heat pipe
CN110883268A (en) * 2019-12-24 2020-03-17 刘义 Steel bar bending device for building engineering

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JP2947362B2 (en) * 1989-09-07 1999-09-13 臼井国際産業株式会社 Tube bending equipment
US5275031A (en) * 1992-06-05 1994-01-04 Stark Manufacturing, Inc. Bend correction apparatus and method
US5835684A (en) 1994-11-09 1998-11-10 Amada Company, Ltd. Method for planning/controlling robot motion
US5761940A (en) * 1994-11-09 1998-06-09 Amada Company, Ltd. Methods and apparatuses for backgaging and sensor-based control of bending operations
US5969973A (en) * 1994-11-09 1999-10-19 Amada Company, Ltd. Intelligent system for generating and executing a sheet metal bending plan
EP1236546A3 (en) * 1994-11-09 2002-12-11 Amada Company, Ltd. Gripper movement control method and apparatus
EP0744046B1 (en) 1994-11-09 2003-02-12 Amada Company Limited Intelligent system for generating and executing a sheet metal bending plan
JPH09225542A (en) * 1996-02-23 1997-09-02 Usui Internatl Ind Co Ltd Device for bending tube to be bent
US5836188A (en) * 1997-04-09 1998-11-17 Pilot Industries, Inc. Method and apparatus for bending an elongated member to a target angle
CA2221324A1 (en) * 1997-11-17 1999-05-17 Eagle Precision Technologies Inc. Tub bending apparatus and method
US6434995B1 (en) 1999-10-15 2002-08-20 Usui Kokusai Sangyo Kaisha Limited Method of bending small diameter metal pipe and its apparatus
US20050005666A1 (en) * 2003-07-10 2005-01-13 Blurton-Jones Timothy John Tube bending apparatus and method
US9767234B2 (en) * 2006-08-31 2017-09-19 Nippon Steel & Sumitomo Metal Corporation Method of identification of cause and/or location of cause of occurrence of springback
US8151427B1 (en) * 2009-03-31 2012-04-10 Honda Motor Co., Ltd. Method of accurately fixturing stamped work parts after trim and bend process
CN105642758A (en) * 2016-02-22 2016-06-08 浙江金禾成汽车空调有限公司 Forming die for U-shaped bent pipes of condensers
CN114210787A (en) * 2021-12-11 2022-03-22 大庆珑达建工集团有限公司 Auxiliary assembly for laying water and electricity pipelines for building construction
CN116020921A (en) * 2023-03-29 2023-04-28 山东津晨佳金属制品有限公司 Real-time angle detection device and control method for seamless steel pipe bending machine
CN117259518B (en) * 2023-11-21 2024-02-23 成都源流立创科技有限公司 Pipe bending device and method for precisely controlling pipe bending angle

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0384477A2 (en) * 1989-02-23 1990-08-29 Rasi Maschinenbau Und -Handels Gmbh Method and machine for bending tubes
EP0384477A3 (en) * 1989-02-23 1991-06-05 Rasi Maschinenbau Und -Handels Gmbh Method and machine for bending tubes
EP0461006A1 (en) * 1990-06-08 1991-12-11 ETAT-FRANCAIS représenté par le Délégué Général pour l' Armement Method and apparatus for bending tubes
FR2662958A1 (en) * 1990-06-08 1991-12-13 France Etat Armement METHOD AND DEVICE FOR BENDING PIPING.
US5127248A (en) * 1990-06-08 1992-07-07 Etat Francais Represente Par Le Delegue General Process and device for pipe bending
EP0719603A1 (en) * 1994-12-26 1996-07-03 Toyota Jidosha Kabushiki Kaisha Supplemental bending method for correcting already bent workpiece, and apparatus for determining information for supplemental bending on the workpiece
US5634362A (en) * 1994-12-26 1997-06-03 Toyota Jidosha Kabushiki Kaisha Supplemental bending method for correcting already bent workpiece, and apparatus for determining information for supplemental bending on the workpiece
WO2005016567A1 (en) * 2003-08-05 2005-02-24 Rosenberger Ag Method for determining the elastic recovery value of a workpiece that is bent in a bending machine equipped with at least one bending arm
WO2007121985A1 (en) * 2006-04-24 2007-11-01 Rasi Maschinenbau Gmbh Method for the mechanical tensile bending of bars, more particularly pipes
CN102632118A (en) * 2012-05-08 2012-08-15 古河奇宏电子（苏州）有限公司 Automatic bending device for heat pipe
CN102632118B (en) * 2012-05-08 2014-04-02 古河奇宏电子（苏州）有限公司 Automatic bending device for heat pipe
CN110883268A (en) * 2019-12-24 2020-03-17 刘义 Steel bar bending device for building engineering
CN110883268B (en) * 2019-12-24 2021-05-25 中国建筑第五工程局有限公司 Steel bar bending device for building engineering

Also Published As

Publication number Publication date
DE338944T1 (en) 1990-07-05
DE68900564D1 (en) 1992-01-30
EP0338944B1 (en) 1991-12-18
ES2028465T3 (en) 1992-07-01
JPH01306021A (en) 1989-12-11
ATE70473T1 (en) 1992-01-15
US4979385A (en) 1990-12-25
FR2630358A1 (en) 1989-10-27
FR2630358B1 (en) 1993-12-10

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