WO1997028914A1 - Method for making a wheel for a land motor vehicle - Google Patents

Method for making a wheel for a land motor vehicle Download PDF

Info

Publication number
WO1997028914A1
WO1997028914A1 PCT/FR1997/000243 FR9700243W WO9728914A1 WO 1997028914 A1 WO1997028914 A1 WO 1997028914A1 FR 9700243 W FR9700243 W FR 9700243W WO 9728914 A1 WO9728914 A1 WO 9728914A1
Authority
WO
WIPO (PCT)
Prior art keywords
wheel
stress
rim
impact
service
Prior art date
Application number
PCT/FR1997/000243
Other languages
French (fr)
Inventor
Guy Marron
Luc Moinier
Pascal Patou
Original Assignee
Sollac
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sollac filed Critical Sollac
Priority to EP97903421A priority Critical patent/EP0879105B1/en
Priority to DE69704052T priority patent/DE69704052T2/en
Priority to AT97903421T priority patent/ATE199070T1/en
Publication of WO1997028914A1 publication Critical patent/WO1997028914A1/en

Links

Classifications

    • 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
    • B21D53/00—Making other particular articles
    • B21D53/26—Making other particular articles wheels or the like

Definitions

  • the present invention relates to a method for producing a wheel for a motor vehicle comprising a wheel disc and a substantially cylindrical rim, the wheel disc being made up, of a substantially planar central part comprising a bearing which serves to center and to fix the wheel on the hub of the vehicle axle, a substantially conical interior rise, another inverted conical part defining, with the interior rise, a curve nose which has a large radius of curvature, the inverted conical part, rear part of the curved nose, ending with a fallen edge intended for the connection of the veil with the rim.
  • the wheel disc and the rim are generally obtained by stamping and / or flow turning from a homogeneous sheet blank.
  • the operations of forming a wheel wall from a single homogeneous sheet blank have the major drawback of not distributing, in particular, the thicknesses as desired. It is not possible to have physical and mechanical characteristics defined in areas for example, the most stressed or, to have thinning in areas of less mechanical stress. When the wheel is analyzed mechanically, it appears that in operation, the most stressed area of the wheel runout is the curve nose and the least stressed area of said runout is the fallen edge. To ensure in certain places a minimum admissible thickness, the sheet is oversized in thickness because it is necessary to take into account the localized thinning generated by the forming operation of the sheet blank. As a result, the wheel is overweight due to its design.
  • the stress is generated by a compression of the sheet by means of a wheel.
  • Compression of the work-hardening type causes surface plastic deformations which are detrimental to the visual appearance and the fatigue strength.
  • work hardening can lead to incipient fractures.
  • the stresses induced by this method are located in the extreme skin of the rim, which consequently limits their effect in the case in particular of the tensile-compression stresses encountered on the wheels in service.
  • the recommended type of work hardening must be carried out before painting the surface of the wheel.
  • a subsequent paint treatment associated with the thermal treatment of baking the paint has the effect of partially relaxing the stresses induced by the wheel and thereby reducing the effectiveness of the method.
  • the stress field resulting from the forming operation in the critical zone of the curve nose has a "Z" characteristic.
  • the lower skin of the shaping nose, or else, the concave part of the shaping nose is subjected to compression
  • the so-called upper skin, or else, the convex part of the shaping nose is subjected to tension.
  • the fatigue of the rotary bending type is locally assimilated to a bending of the alternating plane bending type at the level of the curve nose. That is to say that the loading of the wheel subjects the lower skin of the curve nose sometimes to a tensile force sometimes to a compression force, the behavior being reversed as regards the upper skin of the curve nose.
  • the profile of the stresses in service of the wheel is the superposition of the two stress profiles resulting on the one hand from the forming of the wheel face and on the other hand from the load of the wheel in service.
  • the object of the invention is to provide lightening of the wheel by locally improving the mechanical characteristics of said wheel, and this, by modifying the internal stress profile resulting from forming in certain parts of the wheel.
  • the subject of the invention is a method for producing a wheel for a motor vehicle in which:
  • a stress field opposing the stress field induced by the shaping and loading of the wheel in service is generated in the critical stress zones of the wheel in service, to compensate for the internal stress profile resulting from the forming wheel disc and / or rim so that the stress in service remains less than or equal to the maximum allowable stress.
  • a coating is deposited on the area which absorbs part of the energy of the LASER radiation, - a layer transparent to the LASER radiation is deposited on the coating.
  • the invention also relates to a wheel for a motor vehicle obtained by implementing the method.
  • Figure 1 is a sectional view of a wheel of a land motor vehicle having the different parts of said wheel.
  • Figure 2 is an explanatory sketch of the physical phenomenon generated by the impact of LASER radiation.
  • Figure 3 is a sectional view of a vehicle wheel according to the invention subjected to the impact of LASER radiation.
  • the invention relates to a method of producing a wheel 1 for a motor vehicle comprising, as shown in FIG. 1, a wheel disc 2 and a substantially cylindrical rim 3, the wheel disc 2 being made up of a substantially flat central part 4 having a bearing surface 5 which serves to center and fix the wheel 1 on a hub of an axle, a interior rise 6 substantially conical, another inverted conical part 7 defining, with the interior rise 6 a curved nose 8 which has a large radius of curvature, the inverted conical part 7, rear part of the curved nose 8, ending in a dropped edge 9, intended for the connection of the web 2 with the rim 3.
  • the invention relates to a method for producing a wheel wall in which:
  • the main dimension parameters of the wheels are the thickness of the starting blank and the steel grade used. Taking into account the choice of steel grade, the thickness of the starting blank is chosen by calculating the stress value at the level of the critical zone, for example of the curve nose.
  • an internal stress field opposing the stress field induced by the shaping of the web and / or the rim and the load in service are generated in a critical stress area of the wheel in service. said wheel.
  • - at least one critical zone of stress of the wheel is subjected to an impact inducing in the zone, compressive stresses by shock wave.
  • At least one critical zone of stress of the wheel is subjected to the impact of a water jet. In another example of application of the invention, at least one critical zone of stress of the wheel is subjected to the impact of LASER radiation.
  • the method of the invention does not in any way modify the visual appearance of the critical zone.
  • the impact does not produce a macroscopic surface defect, which avoids any initiation of induced rupture.
  • the impact based on the principle of a shock wave, generates induced stresses in depth, which can influence 8 mm in depth under critical area, the process is therefore well suited for the loading of a sheet.
  • the method of the invention can be used on a wheel which has already been coated with a paint and subjected to baking temperature.
  • Zone 1 1 focused is transformed into plasma and the high pressure generated is transmitted to the metal surface 1 2 via a very strong shock wave.
  • a coating 1 3 absorbing the radiation of the beam 10 LASER.
  • a layer transparent to the radiation of the LASER can be deposited on the coating 13.
  • the residual stress value generated by the shock can reach 300 MPa at the surface, 100 MPa at 0.5 mm deep and around 1 mm, the stress level is practically zero.
  • the pressure of the jet is more than 4000 Kg / cm 2 for a flow rate of 6 liters / min.
  • two modes can be envisaged from the point of view of the distribution of the impact.
  • a first mode the wheel is fixed.
  • the impact for example of a LASER radiation can be generated by a localized beam 10 deflected by a conical prism, a fixed annular mirror directing the beam, for example, on the inner part 12 of the curve nose.
  • the impact can be punctual, the beam 10 directed on a mirror 1 6 rotating for the scanning for example of the interior part 1 5 of the curve nose 8.
  • the wheel In a second mode, the wheel is in rotation.
  • the impact, for example, of LASER radiation is generated by a continuous or pulsed fixed beam, the target of which is a point on a generator of the veil of the wheel, a generator belonging for example to the curve nose.
  • the level of stress in service in the critical zone of a wheel disc requires a sheet blank thickness of 4.4 mm when the method according to the invention is not implemented.
  • a reduction in the thickness of the sheet blank of the order of 1.4 mm can be accepted by compressing the critical zone of the curve nose by approximately 160 MPa.
  • the weight gain is then 1.5 kg, for a wheel which, according to the invention will weigh approximately 3.5 kg, which generates a gain of 30%.

Abstract

A method for making a wheel for a land motor vehicle, comprising a wheel disc and a substantially cylindrical wheel rim. The wheel disc consists of a substantially planar central portion with a bearing for centring and fixing the wheel on an axle hub, a substantially tapered inner connecting portion, and a further oppositely tapered portion defining a bulge with said inner connecting portion. The bulge has a large radius of curvature and the oppositely tapered portion behind the bulge ends in a flange for joining the disc to the rim. The method comprises selecting, for a given grade of steel, a sheet metal blank with a thickness defined by calculating the stress value in the critical stress areas of the wheel in use; shaping and assembling the wheel disc and rim; and generating an internal stress field in the critical stress areas of the wheel in use, which field counters the stress field induced during the shaping step and by the working load on the wheel, in order to compensate for the induced stress arising from the wheel disc or rim forming step, and so that the working stress does not exceed the maximum allowable stress.

Description

Procédé de réalisation d'une roue pour véhicule terrestre à moteur. Method for producing a wheel for a land motor vehicle.
La présente invention concerne un procédé de réalisation d'une roue pour véhicule à moteur comportant un voile de roue et une jante sensiblement cylindrique, le voile de roue étant constitué, d'une partie centrale sensiblement plane comportant une portée qui sert à centrer et à fixer la roue sur le moyeu de l'essieu du véhicule, une montée intérieure sensiblement conique, une autre partie conique inversée définissant, avec la montée intérieure, un nez de galbe qui présente un rayon de courbure important, la partie conique inversée, partie arrière du nez de galbe, se terminant par un bord tombé destiné à la liaison du voile avec la jante.The present invention relates to a method for producing a wheel for a motor vehicle comprising a wheel disc and a substantially cylindrical rim, the wheel disc being made up, of a substantially planar central part comprising a bearing which serves to center and to fix the wheel on the hub of the vehicle axle, a substantially conical interior rise, another inverted conical part defining, with the interior rise, a curve nose which has a large radius of curvature, the inverted conical part, rear part of the curved nose, ending with a fallen edge intended for the connection of the veil with the rim.
Le voile de roue et la jante sont généralement obtenus par emboutissage et/ou fluotournage à partir d'un flan de tôle homogène.The wheel disc and the rim are generally obtained by stamping and / or flow turning from a homogeneous sheet blank.
Les différentes opérations de formage donnent en final, un profil du voile de roue généralement constitué de cinq zones circulaires concentriques, qui sont :The different forming operations ultimately give a profile of the wheel disc generally consisting of five concentric circular zones, which are:
- la partie centrale qui sert à fixer la roue sur le moyeu de l'essieu du véhicule,- the central part which is used to fix the wheel on the hub of the vehicle axle,
- la montée intérieure conique reliant la partie centrale et le sommet de la roue appelé nez de galbe,- the conical internal rise connecting the central part and the top of the wheel called the curve nose,
- le nez de galbe qui présente un rayon de courbure important,- the curved nose which has a large radius of curvature,
- la partie arrière du nez de galbe sur laquelle se situe des ajourages d'allégement,- the rear part of the curve nose on which there are lightening openings,
- le bord tombé de la partie arrière par lequel est généralement réalisée la liaison du voile de roue avec la jante.- the fallen edge of the rear part by which the wheel disc is generally connected with the rim.
Les opérations de formage d'un voile de roue à partir d'un flan de tôle unique homogène, ont pour inconvénient majeur de ne pas distribuer notamment, les épaisseurs comme on le désirerait. Il n'est pas possible d'avoir des caractéristiques physiques et mécaniques définies dans des zones par exemple, les plus sollicitées ou encore, d'avoir des amincissements dans des zones de moindres contraintes mécaniques. Lorsqu'on analyse mécaniquement la roue, il apparaît qu'en fonctionnement, la zone la plus sollicitée du voile de roue est le nez de galbe et la zone la moins sollicitée dudit voile est le bord tombé. Pour assurer en certains endroits une épaisseur minimale admissible, la tôle est sur-dtmensionnée en épaisseur car il faut tenir compte des amincissements localisés généré par l'opération de formage du flan de tôle. De ce fait la roue présente un excès de poids de par sa conception. La zone critique en fatigue du voile de roue est la partie concave du nez de galbe. Cette zone a tendance à se fissurer lorsque la roue est soumise à fatigue. Il est connu qu'une contrainte en compression est favorable à la tenue en fatigue. Le document US 4 448 053 traite d'une méthode pour générer une contrainte de compression sur une jante d'une roue de véhicule.The operations of forming a wheel wall from a single homogeneous sheet blank have the major drawback of not distributing, in particular, the thicknesses as desired. It is not possible to have physical and mechanical characteristics defined in areas for example, the most stressed or, to have thinning in areas of less mechanical stress. When the wheel is analyzed mechanically, it appears that in operation, the most stressed area of the wheel runout is the curve nose and the least stressed area of said runout is the fallen edge. To ensure in certain places a minimum admissible thickness, the sheet is oversized in thickness because it is necessary to take into account the localized thinning generated by the forming operation of the sheet blank. As a result, the wheel is overweight due to its design. The critical zone in fatigue of the wheel disc is the concave part of the curve nose. This area tends to crack when the wheel is subjected to fatigue. It is known that a compressive stress is favorable to fatigue resistance. Document US 4,448,053 deals with a method for generating a compressive stress on a rim of a vehicle wheel.
Dans cette méthode, la contrainte est générée par une compression de la tôle au moyen d'une molette. La compression de type par écrouissage entraîne des déformations plastiques superficielles qui sont préjudiciables à l'aspect visuel et à la tenue en fatigue. En effet, l'écrouissage peut entraîner des amorces de rupture. De plus, les contraintes induites par cette méthode sont localisées en extrême peau de la jante, ce qui limite de façon conséquente leur effet dans le cas notamment des sollicitations en traction-compression rencontrées sur les roues en service. Dans un autre domaine, le traitement de type par écrouissage préconisé doit être effectué avant traitement en peinture de la surface de la roue. Un traitement de peinture ultérieur associé au traitement thermique de cuisson de la peinture a pour effet de relaxer partiellement les contraintes induites par la molette et réduire de ce fait l'efficacité de la méthode.In this method, the stress is generated by a compression of the sheet by means of a wheel. Compression of the work-hardening type causes surface plastic deformations which are detrimental to the visual appearance and the fatigue strength. In fact, work hardening can lead to incipient fractures. In addition, the stresses induced by this method are located in the extreme skin of the rim, which consequently limits their effect in the case in particular of the tensile-compression stresses encountered on the wheels in service. In another field, the recommended type of work hardening must be carried out before painting the surface of the wheel. A subsequent paint treatment associated with the thermal treatment of baking the paint has the effect of partially relaxing the stresses induced by the wheel and thereby reducing the effectiveness of the method.
Le champ de contrainte issu de l'opération de formage dans la zone critique du nez de galbe a une caractéristique en "Z". Au point mort bas de l'opération de formage la peau inférieure du nez de galbe, ou encore, la partie concave du nez de galbe, est soumise à compression, la peau dite supérieure, ou encore, la partie convexe du nez de galbe, est soumise à traction. On remarque que la fatigue de type flexion rotative s'assimile localement à une flexion de type flexion plane alternée au niveau du nez de galbe. C'est à dire que le chargement de la roue soumet la peau inférieure du nez de galbe tantôt à un effort en traction tantôt à un effort en compression, le comportement étant inversé en ce qui concerne la peau supérieure du nez de galbe. En d'autres termes, le profil des contraintes en service de la roue est la superposition des deux profils de contrainte issus d'une part du formage du voile de roue et d'autre part de la charge de la roue en service. Le but de l'invention est d'assurer un allégement de la roue en améliorant localement, les caractéristiques mécaniques de ladite roue, et cela, en modifiant le profil de contrainte interne issu du formage dans certaines parties de la roue. L'invention a pour objet un procédé de réalisation d'une roue pour véhicule à moteur dans lequelle :The stress field resulting from the forming operation in the critical zone of the curve nose has a "Z" characteristic. At the bottom dead center of the forming operation, the lower skin of the shaping nose, or else, the concave part of the shaping nose, is subjected to compression, the so-called upper skin, or else, the convex part of the shaping nose, is subjected to tension. It is noted that the fatigue of the rotary bending type is locally assimilated to a bending of the alternating plane bending type at the level of the curve nose. That is to say that the loading of the wheel subjects the lower skin of the curve nose sometimes to a tensile force sometimes to a compression force, the behavior being reversed as regards the upper skin of the curve nose. In other words, the profile of the stresses in service of the wheel is the superposition of the two stress profiles resulting on the one hand from the forming of the wheel face and on the other hand from the load of the wheel in service. The object of the invention is to provide lightening of the wheel by locally improving the mechanical characteristics of said wheel, and this, by modifying the internal stress profile resulting from forming in certain parts of the wheel. The subject of the invention is a method for producing a wheel for a motor vehicle in which:
- on choisit, pour une nuance d'acier donnée, un flan de tôle dont l'épaisseur est définie par le calcul de la valeur de contrainte au niveau des zones critiques de contrainte de la roue en service,- a sheet blank whose thickness is defined by the calculation of the stress value at the critical stress zones of the wheel in service is chosen for a given steel grade,
- on forme le voile de roue et la jante que l'on assemble,- we form the wheel disc and the rim that we assemble,
- on génère dans les zones critiques de contraintes de la roue en service un champ de contrainte s'opposant au champ de contrainte induit par la mise en forme et le chargement en service de la roue, pour compenser le profil de contraintes internes issu du formage du voile de roue et ou de la jante de manière que la contrainte en service reste inférieure ou égale à la contrainte maximaie admissible. Les autres caractéristiques de l'invention sont:- a stress field opposing the stress field induced by the shaping and loading of the wheel in service is generated in the critical stress zones of the wheel in service, to compensate for the internal stress profile resulting from the forming wheel disc and / or rim so that the stress in service remains less than or equal to the maximum allowable stress. The other characteristics of the invention are:
- on génère dans au moins une zone critique de contraintes de la roue un champ de contrainte de compression par impact et onde de choc,- a compressive stress and impact wave stress field is generated in at least one critical stress zone of the wheel,
- on soumet au moins une zone critique de contraintes de la roue à l'impact d'un jet d'eau,- at least one critical zone of wheel stresses is subjected to the impact of a water jet,
- on soumet au moins une zone critique de contraintes de la roue à l'impact d'un rayonnement LASER, - on soumet la partie concave du nez de galbe du voile de roue à l'impact induisant dans cette partie, des contraintes de compression par impact et onde de choc,- at least one critical zone of wheel stresses is subjected to the impact of LASER radiation, - the concave part of the curve of the wheel runout is subjected to the impact inducing in this part, compression stresses by impact and shock wave,
- on dépose sur la zone un revêtement qui absorbe une partie de l'énergie du rayonnement LASER, - on dépose sur le revêtement une couche transparente au rayonnement LASER.- a coating is deposited on the area which absorbs part of the energy of the LASER radiation, - a layer transparent to the LASER radiation is deposited on the coating.
L'invention concerne également une roue pour véhicule à moteur obtenue par la mise en oeuvre du procédé.The invention also relates to a wheel for a motor vehicle obtained by implementing the method.
La description qui suit et les figures annexées, le tout donné à titre d'exemple non limitatif fera bien comprendre l'invention.The following description and the appended figures, all given by way of nonlimiting example will make the invention better understood.
La figure 1 est une vue en coupe d'une roue de véhicule terrestre à moteur présentant les différentes parties de ladite roue.Figure 1 is a sectional view of a wheel of a land motor vehicle having the different parts of said wheel.
La figure 2 est un croquis explicatif du phénomène physique généré par l'impact d'un rayonnement LASER. La figure 3 est une vue en coupe d'une roue de véhicule selon l'invention soumise à l'impact d'un rayonnement LASER.Figure 2 is an explanatory sketch of the physical phenomenon generated by the impact of LASER radiation. Figure 3 is a sectional view of a vehicle wheel according to the invention subjected to the impact of LASER radiation.
L'invention traite d'un procédé de réalisation d'une roue 1 pour véhicule à moteur comportant, comme représenté sur la figure 1 , un voile 2 de roue et une jante 3 sensiblement cylindrique, le voile 2 de roue étant constitué, d'une partie centrale 4 sensiblement plane comportant une portée 5 qui sert à centrer et à fixer la roue 1 sur un moyeu d'un essieu, une montée 6 intérieure sensiblement conique, une autre partie conique inversée 7 définissant, avec la montée 6 intérieure un nez de galbe 8 qui présente un rayon de courbure important, la partie conique inversée 7, partie arrière du nez de galbe 8, se terminant par un bord tombé 9, destiné à la liaison du voile 2 avec la jante 3.The invention relates to a method of producing a wheel 1 for a motor vehicle comprising, as shown in FIG. 1, a wheel disc 2 and a substantially cylindrical rim 3, the wheel disc 2 being made up of a substantially flat central part 4 having a bearing surface 5 which serves to center and fix the wheel 1 on a hub of an axle, a interior rise 6 substantially conical, another inverted conical part 7 defining, with the interior rise 6 a curved nose 8 which has a large radius of curvature, the inverted conical part 7, rear part of the curved nose 8, ending in a dropped edge 9, intended for the connection of the web 2 with the rim 3.
L'invention traite d'un procédé de réalisation d'un voile de roue dans lequel :The invention relates to a method for producing a wheel wall in which:
Le paramètres dimensionneis principaux des roues sont l'épaisseur du flan de départ et la nuance d'acier utilisée. Compte tenu du choix de la nuance d'acier, on choisit l'épaisseur du flan de départ par calcul de la valeur de contrainte au niveau de la zone critique par exemple du nez de galbe.The main dimension parameters of the wheels are the thickness of the starting blank and the steel grade used. Taking into account the choice of steel grade, the thickness of the starting blank is chosen by calculating the stress value at the level of the critical zone, for example of the curve nose.
Selon l'invention, on génère dans une zone critique de contrainte de la roue en service un champ de contrainte interne s'opposant au champ de contrainte induit par la mise en forme du voile et/ou de la jante et la charge en service de ladite roue. Selon l'invention, - on soumet au moins une zone critique de contrainte de la roue à un impact induisant dans la zone, des contraintes de compression par onde de choc.According to the invention, an internal stress field opposing the stress field induced by the shaping of the web and / or the rim and the load in service are generated in a critical stress area of the wheel in service. said wheel. According to the invention, - at least one critical zone of stress of the wheel is subjected to an impact inducing in the zone, compressive stresses by shock wave.
Dans un exemple d'application de l'invention, on soumet au moins une zone critique de contrainte de la roue à l'impact d'un jet d'eau. Dans un autre exemple d'application de l'invention, on soumet au moins une zone critique de contrainte de la roue à l'impact d'un rayonnement LASER.In an example of application of the invention, at least one critical zone of stress of the wheel is subjected to the impact of a water jet. In another example of application of the invention, at least one critical zone of stress of the wheel is subjected to the impact of LASER radiation.
Le procédé de l'invention ne modifie en rien l'aspect visuel de la zone critique. L'impact ne produit pas de défaut macroscopique de surface, ce qui évite toute amorce de rupture induite. L'impact, basé sur le principe d'une onde de choc, génère des contraintes induites en profondeur, pouvant influer sur 8 mm en profondeur sous zone critique, le procédé est donc bien adapté pour la sollicitation d'une tôle.The method of the invention does not in any way modify the visual appearance of the critical zone. The impact does not produce a macroscopic surface defect, which avoids any initiation of induced rupture. The impact, based on the principle of a shock wave, generates induced stresses in depth, which can influence 8 mm in depth under critical area, the process is therefore well suited for the loading of a sheet.
De plus, le procédé de l'invention peut être utilisé sur une roue ayant déjà été revêtue d'une peinture et soumise à température de cuisson.In addition, the method of the invention can be used on a wheel which has already been coated with a paint and subjected to baking temperature.
Comme représenté sur la figure 2, la zone critique est exposée à un puissant faisceau 10 LASER pendant un. temps très court. La zone 1 1 focalisée est transformée en plasma et la forte pression engendrée est transmise à la surface 1 2 métallique via une très forte onde de choc. Pour augmenter l'efficacité du choc, on peut déposer sur la surface 1 2 soumise à l'impact un revêtement 1 3 absorbant le rayonnement du faisceau 10 LASER.As shown in Figure 2, the critical area is exposed to a strong 10 LASER beam for one. very short time. Zone 1 1 focused is transformed into plasma and the high pressure generated is transmitted to the metal surface 1 2 via a very strong shock wave. To increase the effectiveness of the impact, one can deposit on the surface 1 2 subjected to the impact a coating 1 3 absorbing the radiation of the beam 10 LASER.
Pour confiner le choc, une couche transparente 14 au rayonnement du LASER peut être déposé sur le revêtement 13.To confine the shock, a layer transparent to the radiation of the LASER can be deposited on the coating 13.
La valeur de contrainte résiduelle engendrée par le choc peut atteindre 300 MPa en surface, 100 MPa à 0,5 mm de profondeur et vers 1 mm, le niveau de contrainte est pratiquement nul.The residual stress value generated by the shock can reach 300 MPa at the surface, 100 MPa at 0.5 mm deep and around 1 mm, the stress level is practically zero.
Dans le cas de l'utilisation d'un impact par jet d'eau, la pression du jet est de plus de 4000 Kg/cm2 pour un débit de 6 litres/mn.In the case of the use of a water jet impact, the pressure of the jet is more than 4000 Kg / cm 2 for a flow rate of 6 liters / min.
L'utilisation d'une buse appropriée couplée à des paramètres spécifiques de l'installation permet de générer des chocs sur la tôle d'acier dont est formée la roue sans avoir d'arrachement de matière.The use of an appropriate nozzle coupled to specific parameters of the installation makes it possible to generate shocks on the steel sheet of which the wheel is formed without having material tearing.
On peut définir par calcul l'épaisseur minimale en chaque point par exemple du voile de roue pour qu'il soit correctement dimensionné en contrainte. Il suffit donc de modifier le profil de contraintes internes issu du formage dans la zone critique du nez de galbe pour que finalement le niveau de contraintes en service soit homogène dans tout le voile. Par conséquent, l'épaisseur de la zone critique ne nécessite plus un sur dimentionnement lors du choix de l'épaisseur de la tôle à l'origine.We can define by calculation the minimum thickness at each point for example of the wheel disc so that it is correctly dimensioned in stress. It therefore suffices to modify the internal stress profile resulting from the forming in the critical zone of the contour nose so that finally the level of stresses in service is homogeneous throughout the veil. Consequently, the thickness of the critical zone no longer requires oversizing when choosing the thickness of the sheet at the origin.
Dans le principe de la mise en oeuvre du procédé, deux modes peuvent être envisagés du point de vue de la distribution de l'impact. Dans un premier mode, la roue est fixe. L'impact par exemple d'un rayonnement LASER peut être généré par un faisceau 10 localisé dévié par un prisme conique, un miroir annulaire fixe dirigeant le faisceau, par exemple, sur la partie 12 intérieure du nez de galbe .In the principle of implementing the method, two modes can be envisaged from the point of view of the distribution of the impact. In a first mode, the wheel is fixed. The impact for example of a LASER radiation can be generated by a localized beam 10 deflected by a conical prism, a fixed annular mirror directing the beam, for example, on the inner part 12 of the curve nose.
L'impact peut être ponctuel, le faisceau 10 dirigé sur un miroir 1 6 tournant pour le balayage par exemple de la partie 1 5 intérieure du nez de galbe 8.The impact can be punctual, the beam 10 directed on a mirror 1 6 rotating for the scanning for example of the interior part 1 5 of the curve nose 8.
Dans un second mode, la roue est en rotation. L'impact par exemple d'un rayonnement LASER est généré par un faisceau fixe continu ou puisé dont la cible est un point d'une génératrice du voile de la roue, génératrice appartenant par exemple au nez de galbe.In a second mode, the wheel is in rotation. The impact, for example, of LASER radiation is generated by a continuous or pulsed fixed beam, the target of which is a point on a generator of the veil of the wheel, a generator belonging for example to the curve nose.
Le fait de modifier localement le profil de contraintes internes par le procédé selon l'invention et suivant les modes exposés ci dessus, permet de définir le choix d'une épaisseur de tôle d'acier au départ non surdimenssioπnée. Le gain de poids est de ce fait notable.The fact of locally modifying the internal stress profile by the method according to the invention and according to the modes described above, allows you to define the choice of a steel sheet thickness at the start not oversized. The weight gain is therefore noticeable.
Il est possible de cumuler les moyens d'impact comme un rayonnement LASER et un jet d'eau. Par exemple, l'impact LASER sous une pélicule d'eau améliore notamment l'effet de compression.It is possible to combine impact means such as LASER radiation and a water jet. For example, the LASER impact under a film of water notably improves the compression effect.
Le niveau de contrainte en service dans la zone critique d'un voile de roue nécessite une épaisseur de flan de tôle de 4,4 mm lorsque le procédé selon l'invention n'est pas mis en oeuvre.The level of stress in service in the critical zone of a wheel disc requires a sheet blank thickness of 4.4 mm when the method according to the invention is not implemented.
Selon le procédé de l'invention, une diminution de l'épaisseur du flan de tôle de l'ordre de 1 ,4 mm peut être acceptée par une mise en compression de la zone critique du nez de galbe d'environ 160 MPa . Le gain de poids est alors de 1 ,5 Kg, pour une roue qui, selon l'invention pèsera environ 3,5 Kg, ce qui génère un gain de 30%. According to the method of the invention, a reduction in the thickness of the sheet blank of the order of 1.4 mm can be accepted by compressing the critical zone of the curve nose by approximately 160 MPa. The weight gain is then 1.5 kg, for a wheel which, according to the invention will weigh approximately 3.5 kg, which generates a gain of 30%.

Claims

REVENDICATIONS
1. Procédé de réalisation d'une roue pour véhicule à moteur comportant un voile (2) de roue et une jante (3) sensiblement cylindrique, le voile (2) de roue étant constitué, d'une partie centrale (4) sensiblement plane comportant une portée (5) qui sert à centrer et à fixer la roue (1 ) sur un moyeu de l'essieu, une montée (6) intérieure sensiblement conique, une autre partie conique inversée (7) définissant, avec la montée (6) intérieure un nez de galbe (8) qui présente un rayon de courbure important, la partie conique inversée (7), partie arrière du nez de galbe (8), se terminant par un bord tombé (9) destiné à la liaison du voile (2) avec la jante (3), caractérisé en ce que :1. Method for producing a wheel for a motor vehicle comprising a wheel cover (2) and a substantially cylindrical rim (3), the wheel cover (2) consisting of a substantially flat central part (4) comprising a bearing surface (5) which serves to center and fix the wheel (1) on an axle hub, a substantially conical internal rise (6), another inverted conical part (7) defining, with the rise (6 ) inside a curve nose (8) which has a large radius of curvature, the inverted conical part (7), rear part of the curve nose (8), ending in a fallen edge (9) intended for the connection of the web (2) with the rim (3), characterized in that:
- on choisit, pour une nuance d'acier donnée, un flan de tôle dont l'épaisseur est définie par le calcul de la valeur de contrainte au niveau des zones critiques de contrainte de la roue en service,- a sheet blank whose thickness is defined by the calculation of the stress value at the critical stress zones of the wheel in service is chosen for a given steel grade,
- on forme le voile de roue et la jante que l'on assemble,- we form the wheel disc and the rim that we assemble,
- on génère dans les zones critiques de contrainte de la roue en service un champ de contrainte s'opposant au champ de contrainte induit par la mise en forme et la charge en service de la roue pour compenser les contraintes induites issues du formage du voile de roue et ou de la jante, de manière que la contrainte en service de la roue reste inférieure ou égale à la contrainte maximale admissible.- A stress field opposing the stress field induced by the shaping and the load in service of the wheel is generated in the critical stress zones of the wheel in service to compensate for the stresses induced by the forming of the web of wheel and / or rim, so that the service stress of the wheel remains less than or equal to the maximum allowable stress.
2. Procédé selon la revendication 1 , caractérisé en ce que, on génère dans au moins une zone critique de contrainte de la roue un champ de contrainte de compression par impact et onde de choc,2. Method according to claim 1, characterized in that, in at least one critical zone of stress of the wheel, a compressive stress field by impact and shock wave is generated,
3. Procédé selon les revendications 1 et 2 caractérisé en ce que, on soumet au moins une zone critique de contrainte de la roue à l'impact d'un jet d'eau.3. Method according to claims 1 and 2 characterized in that, at least one critical zone of stress of the wheel is subjected to the impact of a water jet.
4. Procédé selon les revendications 1 et 2 caractérisé en ce que, on soumet au moins une zone critique de contrainte de la roue à l'impact d'un rayonnement LASER.4. Method according to claims 1 and 2 characterized in that, at least one critical zone of stress of the wheel is subjected to the impact of LASER radiation.
5. Procédé selon les revendications 1 à 4 caractérisé en ce que, on soumet la partie concave du nez de galbe du voile de roue à l'impact induisant dans cette partie, des contraintes de compression par onde de S choc de manière que la contrainte en service de la roue reste inférieure ou égale à la contrainte maximale admissible,5. Method according to claims 1 to 4 characterized in that, the concave part of the curve of the wheel face is subjected to the impact inducing in this part, compressive stresses by wave of S impact so that the service stress of the wheel remains less than or equal to the maximum allowable stress,
6. Procédé selon les revendications 1 à 5 caractérisé en ce que, on dépose sur la zone critique de contrainte un revêtement qui absorbe une partie de l'énergie du rayonnement LASER,6. Method according to claims 1 to 5 characterized in that, a coating is deposited on the critical stress zone which absorbs part of the energy of the LASER radiation,
7. Procédé selon les revendications 1 à 6 caractérisé en ce que, on dépose sur le revêtement une couche transparente au rayonnement LASER.7. Method according to claims 1 to 6 characterized in that, is deposited on the coating a layer transparent to LASER radiation.
8. Roue pour véhicule à moteur comportant un voile (2) de roue et une jante (3) sensiblement cylindrique, le voile (2) de roue étant constitué, d'une partie centrale (4) sensiblement plane comportant une portée (5) qui sert à centrer et à fixer la roue ( 1 ) sur le moyeu de l'essieu, une montée (6) intérieure sensiblement conique, une autre partie conique inversée (7) définissant, avec la montée (6) intérieure un nez de galbe (8) qui présente un rayon de courbure important, la partie conique inversée {7), partie arrière du nez de galbe (8) se terminant par un bord tombé (9) destiné à la liaison du voile (2) avec la jante, ladite roue étant réalisée par le procédé selon les revendications 1 à 7, caractérisé en ce que le niveau de contrainte en service du voile de la roue est homogène. 8. Wheel for a motor vehicle comprising a wheel cover (2) and a substantially cylindrical rim (3), the wheel cover (2) consisting of a substantially flat central part (4) having a seat (5) which is used to center and fix the wheel (1) on the axle hub, a substantially conical interior rise (6), another inverted conical part (7) defining, with the interior rise (6), a curve nose (8) which has a large radius of curvature, the inverted conical part (7), rear part of the curve nose (8) ending in a fallen edge (9) intended for the connection of the web (2) with the rim, said wheel being produced by the method according to claims 1 to 7, characterized in that the level of stress in service of the web of the wheel is uniform.
PCT/FR1997/000243 1996-02-08 1997-02-07 Method for making a wheel for a land motor vehicle WO1997028914A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP97903421A EP0879105B1 (en) 1996-02-08 1997-02-07 Method for making a wheel for a land motor vehicle
DE69704052T DE69704052T2 (en) 1996-02-08 1997-02-07 METHOD FOR PRODUCING A MOTOR VEHICLE WHEEL
AT97903421T ATE199070T1 (en) 1996-02-08 1997-02-07 METHOD FOR PRODUCING A MOTOR VEHICLE

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9601526A FR2744657B1 (en) 1996-02-08 1996-02-08 METHOD FOR PRODUCING A WHEEL FOR A MOTOR LAND VEHICLE
FR96/01526 1996-02-08

Publications (1)

Publication Number Publication Date
WO1997028914A1 true WO1997028914A1 (en) 1997-08-14

Family

ID=9488968

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FR1997/000243 WO1997028914A1 (en) 1996-02-08 1997-02-07 Method for making a wheel for a land motor vehicle

Country Status (6)

Country Link
EP (1) EP0879105B1 (en)
AT (1) ATE199070T1 (en)
DE (1) DE69704052T2 (en)
ES (1) ES2154024T3 (en)
FR (1) FR2744657B1 (en)
WO (1) WO1997028914A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2810922B1 (en) * 2000-06-30 2002-09-13 Usinor LIGHTWEIGHT AND WIDE BRAKE SPACE

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4448053A (en) * 1982-05-18 1984-05-15 Rockwell International Corporation Method of stress rolling a metallic rim
GB2154492A (en) * 1984-02-22 1985-09-11 Odonnell & Ass Mechanical stress improvement process

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2561144B1 (en) * 1984-03-16 1987-08-07 Barras Provence ALUMINUM ALLOY VEHICLE WHEELS AND METHOD AND DEVICES FOR MANUFACTURING THE SAME

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4448053A (en) * 1982-05-18 1984-05-15 Rockwell International Corporation Method of stress rolling a metallic rim
GB2154492A (en) * 1984-02-22 1985-09-11 Odonnell & Ass Mechanical stress improvement process

Also Published As

Publication number Publication date
ES2154024T3 (en) 2001-03-16
DE69704052T2 (en) 2001-08-23
FR2744657B1 (en) 1998-03-06
DE69704052D1 (en) 2001-03-15
EP0879105B1 (en) 2001-02-07
EP0879105A1 (en) 1998-11-25
FR2744657A1 (en) 1997-08-14
ATE199070T1 (en) 2001-02-15

Similar Documents

Publication Publication Date Title
CA2363302C (en) Shot-peening of cooled blade tops
EP1752234B1 (en) Metallic workpiece treated by compressing its underlayers and method for manufacturing such a workpiece
EP1101827B1 (en) Process for ultrasonic shotpeening large annular surfaces of thinwalled workpieces
EP0733000B1 (en) Tyre, rim, supporting ring and assembly comprising same
EP1109702A1 (en) Bumper beam for motor vehicles
EP2507010A1 (en) Method for making a metal reinforcement for a turbine engine blade
WO2002024411A1 (en) Transverse ultrasound peening of blades on a rotor
FR2465601A1 (en) Two part construction wheel rim for road vehicles - has larger section with disc and part rim and small rim edge
EP0949092A1 (en) Bumper for motor vehicle
EP0786312A1 (en) Process treatment for a metallic surface and the manufacturing of a cooking utensil
FR3027256A1 (en) DEVICE FOR PROTECTING A TIRE FLANK
EP0778093A1 (en) Motor vehicle wheel
EP0879105B1 (en) Method for making a wheel for a land motor vehicle
EP0912352B1 (en) Sound absorbing wheel
CA2302849A1 (en) Shock absorbing device and manufacturing process
FR2810922A1 (en) LIGHTWEIGHT AND WIDE BRAKE SPACE
WO2018211194A1 (en) Device for protecting a tyre sidewall
FR2827548A1 (en) Tubeless tire and wheel rim assembly, especially for bicycles, has stepped rim making contact with tire bead at two or more points
EP3455023B1 (en) Method of joining very thick tubular parts by magnetic pulses
EP1638726B1 (en) Means for assembling parts, comprising at least one welding cord created by transparency
EP0622150A1 (en) Laser welding method of stamped workpieces flanges
EP4071001B1 (en) Foam schock absorber for automobile vehicle
FR2664223A1 (en) STEERING WHEEL FRAME FOR MOTOR VEHICLE OR THE LIKE.
CA2164906A1 (en) Energy absorbing beam; thin metal blank for said beam
FR2780463A1 (en) METHOD FOR ASSEMBLING A CLUTCH FLYWHEEL TO A CLUTCH HOUSING

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1997903421

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1997903421

Country of ref document: EP

WWG Wipo information: grant in national office

Ref document number: 1997903421

Country of ref document: EP