EP3269454A1 - Skirt comprising at least three distinct series of shaping air ejecting nozzles, rotary projector of coating product with such a skirt and coating process using it - Google Patents

Abstract

Skirt (20) intended to equip a rotating projector coating product, and the rotating projector comprising this skirt. The skirt (20) has a plurality of air ejection nozzles (40, 42, 44, 46) formed in said skirt (20) for ejecting air jets forming conformation air adapted to conform the jet of air. coating material, said air ejection nozzles (40,42,44,46) comprising at least three sets of separate nozzles (41,43,45,47) each consisting of a plurality of ejection nozzles air (40, 42, 44, 46) fluidically connected to a common supply chamber, specific to said series of nozzles (41, 43, 45, 47). Method of using this skirt in which the series of air nozzles used is changed between two painting steps, thus obtaining a change in the configuration of the paint jet between the two paint streams, for example narrow and wide.

Description

The present invention relates to a skirt for a rotary coating product projector, of the type comprising a plurality of air ejection nozzles formed in said skirt for ejecting air jets forming a conformation air adapted to conform the jet of coating product, said air ejection nozzles comprising at least one series of nozzles consisting of a plurality of air ejection nozzles fluidly connected to a common supply chamber, specific to said series of nozzles.

Conventional spraying by means of rotating projectors is used to apply to objects to be coated, such as motor vehicle bodies, a primer, a base coat and / or a varnish. A rotary coating product projection projector comprises a spraying member rotating at high speed under the effect of a rotating drive system, such as a compressed air turbine.

Such a spraying member generally has the shape of a rotationally symmetrical bowl and it comprises at least one spraying edge capable of forming a jet of coating product. The rotating projector also comprises a fixed body housing the rotational drive system as well as means for supplying the spray member with a coating product.

The jet of coating material sprayed from the edge of the rotating member has a generally conical shape which depends on such parameters as the rotation speed of the bowl and the flow rate of the coating product. To control the shape of this product jet, the rotary projectors of the prior art are generally equipped with several air ejection nozzles formed in a skirt covering the body of the projector and arranged on a circle which is centered on the axis of symmetry of the bowl and which is located on the outer periphery of the bowl. The air ejection nozzles are intended to emit air jets together forming a conformation air of the product jet. This conformation air, which is sometimes referred to as "skirt air", makes it possible to conform the product jet, in particular to adjust the width of this jet, according to the desired application.

Such a rotating projector is known for example from EP 2 328 689 .

A disadvantage of known rotary projectors is that they do not allow to vary the product jet width over a large amplitude without skirt change. The variation of jet width is thus generally of an amplitude of between 50 and 300 mm or between 300 and 500 mm. If you want to be able to cover the entire spectrum ranging from 50 to 500 mm, it is necessary to change the skirt, which requires complex operations and in particular the preliminary stop of the rotating projector.

However, in several applications of the rotating projectors, it is desirable to allow the spraying of the coating product both in wide jet, that is to say with a jet width of between 300 and 500 mm, and in narrow jet , that is to say with a jet width of between 50 and 300 mm. This need is found particularly in the automotive industry, for which the bodywork interiors must be painted with a narrow jet and the exterior bodywork with a wide jet. Known rotary projectors do not allow this flexibility, the production lines used in the automotive industry usually include two paint booths: a first, dedicated to the painting of body interiors, including a paint projector adapted to make a width of narrow jet, and a second, dedicated to the painting of exterior bodywork, featuring a paint projector suitable for making a wide jet width. This double equipment in paint booths is expensive, both in terms of machine equipment than building space and energy necessary for the operation of the installation.

An object of the invention is thus to allow, with the same rotating projector, to project a coating product either wide jet or narrow jet, without having to change the skirt of the rotating projector.

To this end, the subject of the invention is a rotating projector skirt of the aforementioned type, in which the air ejection nozzles comprise at least three sets of separate nozzles.

• les buses d'éjection d'air comprennent un premier groupe de buses, constitué par au moins une première série de buses parmi les séries de buses, et un deuxième groupe de buses, constitué par au moins une deuxième série de buses parmi les séries de buses, le premier groupe de buses étant tel que, lorsque la ou chaque première série de buses est alimentée en air, les buses de la ou chaque première série de buses éjectent des premiers jets d'air formant ensemble un premier air de conformation adapté pour conformer le jet de produit de revêtement de manière étroite, et le deuxième groupe de buses étant tel que, lorsque la ou chaque deuxième série de buses est alimentée en air, les buses de la ou chaque deuxième série de buses éjectent des deuxièmes jets d'air formant ensemble un deuxième air de conformation adapté pour conformer le jet de produit de revêtement de manière large,
• le premier groupe de buses comprend une première série de buses primaires, constituée de premières buses primaires chacune adaptée pour éjecter un premier jet d'air primaire suivant une première direction primaire, et le deuxième groupe de buses comprend une deuxième série de buses primaires, distincte de la première série de buses primaires et constituée de deuxièmes buses primaires chacune adaptée pour éjecter un deuxième jet d'air primaire suivant une deuxième direction primaire différente de la première direction primaire,
• la première direction primaire est définie par un premier vecteur unitaire primaire présentant une première composante de divergence radiale primaire, et la deuxième direction primaire est définie par un deuxième vecteur unitaire primaire présentant une deuxième composante de divergence radiale primaire, la deuxième composante de divergence radiale primaire étant supérieure à la première composante de divergence radiale primaire,
• la première direction primaire est définie par un premier vecteur unitaire primaire présentant une première composante orthoradiale primaire, et la deuxième direction primaire est définie par un deuxième vecteur unitaire primaire présentant une deuxième composante orthoradiale primaire, la deuxième composante orthoradiale primaire étant supérieure à la première composante orthoradiale primaire,
• chacune des première et deuxième directions primaires est définie par un vecteur unitaire primaire présentant une composante orthoradiale primaire non nulle,
• le premier groupe de buses comprend une première série de buses secondaires, distincte des première et deuxième séries de buses primaires, et le deuxième groupe de buses comprend une deuxième série de buses secondaires, distincte des première et deuxième séries de buses primaires,
• les première et deuxième séries de buses secondaires sont distinctes l'une de l'autre,
• les premières buses des premières séries de buses primaires et secondaires sont disposées en alternance les unes par rapport aux autres, et/ou les deuxièmes buses des deuxièmes séries de buses primaires et secondaires sont disposées en alternance les unes par rapport aux autres ,
• chacune des buses de la première série de buses secondaires est adaptée pour éjecter un premier jet d'air secondaire suivant une première direction secondaire différente de la première direction primaire et de préférence sensiblement sécante à la première direction primaire en une première région d'intersection,
• chacune des buses de la deuxième série de buses secondaires est adaptée pour éjecter un deuxième jet d'air secondaire suivant une deuxième direction secondaire différente de la deuxième direction primaire et de préférence sensiblement sécante à la deuxième direction primaire en une deuxième région d'intersection,
• les premières buses sont disposées à l'intérieur d'un périmètre de séparation, les deuxièmes buses étant disposées à l'extérieur du périmètre de séparation, ou les premières buses sont disposées à l'extérieur d'un périmètre de séparation, les deuxièmes buses étant disposées à l'intérieur du périmètre de séparation, et
• chaque chambre d'alimentation est formée dans la jupe.

According to particular embodiments of the invention, the skirt also has one or more of the following characteristics, taken separately or in any combination (s) technically possible (s):

• the air ejection nozzles comprise a first group of nozzles, constituted by at least a first series of nozzles from the series of nozzles, and a second group of nozzles, constituted by at least a second series of nozzles from the series of nozzles; nozzle, the first group of nozzles being such that, when the or each first series of nozzles is supplied with air, the nozzles of the or each first series of nozzles eject first air jets together forming a first conformation air adapted to conforming the coating material jet in a narrow manner, and the second group of nozzles being such that, when the or each second series of nozzles is supplied with air, the nozzles of the or each second series of nozzles eject second spray nozzles. air together forming a second conformation air adapted to conform the coating product jet broadly,
• the first group of nozzles comprises a first series of primary nozzles, consisting of first primary nozzles each adapted to eject a first primary air jet in a first primary direction, and the second group of nozzles comprises a second series of primary nozzles, separate of the first series of primary nozzles and consisting of second primary nozzles each adapted to eject a second primary air jet in a second primary direction different from the first primary direction,
• the first primary direction is defined by a first primary unit vector having a first primary radial divergence component, and the second primary direction is defined by a second primary unit vector having a second primary radial divergence component, the second primary radial divergence component. being greater than the first component of primary radial divergence,
• the first primary direction is defined by a first primary unit vector having a first primary orthoradial component, and the second primary direction is defined by a second primary unit vector having a second primary orthoradial component, the second primary orthoradial component being greater than the first component orthoradial primary,
• each of the first and second primary directions is defined by a primary unit vector having a non-zero primary orthoradial component,
• the first group of nozzles comprises a first series of secondary nozzles, distinct from the first and second series of primary nozzles, and the second group of nozzles comprises a second series of secondary nozzles, distinct from the first and second series of primary nozzles,
• the first and second series of secondary nozzles are distinct from one another,
• the first nozzles of the first series of primary and secondary nozzles are arranged alternately with respect to each other, and / or the second nozzles of the second series of primary and secondary nozzles are arranged alternately with respect to each other,
• each of the nozzles of the first series of secondary nozzles is adapted to eject a first jet of secondary air in a first secondary direction different from the first primary direction and preferably substantially secant to the first primary direction to a first intersection region,
• each of the nozzles of the second series of secondary nozzles is adapted to eject a second secondary jet of air in a second secondary direction different from the second primary direction and preferably substantially secant to the second primary direction in a second intersection region,
• the first nozzles are disposed within a separation perimeter, the second nozzles being disposed outside the separation perimeter, or the first nozzles are disposed outside a separation perimeter, the second nozzles being arranged inside the perimeter of separation, and
• each feeding chamber is formed in the skirt.

The subject of the invention is also a rotary projector for a coating product comprising at least one spraying member for the coating product, a drive system for driving the first spraying member in rotation about an axis, and a fixed skirt. , the skirt being constituted by a skirt as described above, and each of the supply chambers being formed in the rotating projector.

• l'organe de pulvérisation présente au moins une arête globalement circulaire, chacune des buses d'éjection d'air étant à une distance de l'axe de rotation supérieure ou égale au demi-diamètre de l'arête.

According to a particular embodiment of the invention, the recovery method also has the following characteristic:

• the spraying member has at least one generally circular edge, each of the air ejection nozzles being at a distance from the axis of rotation greater than or equal to the half-diameter of the edge.

The invention further relates to a spray robot comprising an articulated arm, a wrist mounted at one end of the articulated arm, and a rotating projector attached to the wrist, wherein the rotating projector is a rotating projector as described above.

• projection d'un premier jet de produit de revêtement au moyen du projecteur rotatif, seules les buses d'éjection d'air du premier groupe de buses étant alimentées en air, lesdites buses d'éjection d'air éjectant des premiers jets d'air formant ensemble un premier air de conformation conformant le premier jet de produit de revêtement de manière étroite, et
• avant ou après l'étape de projection d'un premier jet de produit de revêtement, projection d'un deuxième jet de produit de revêtement au moyen du projecteur rotatif, seules les buses d'éjection d'air du deuxième groupe de buses étant alimentées en air, lesdites buses d'éjection d'air éjectant des deuxièmes jets d'air formant ensemble un deuxième air de conformation conformant le deuxième jet de produit de revêtement de manière large.

Finally, the invention also relates to a method of covering at least a portion of at least one object with a coating product projected by means of a rotating projector as described above, in which the nozzles of air ejection comprises a first group of nozzles, consisting of at least a first series of nozzles from the series of nozzles, and a second group of nozzles, consisting of at least a second series of nozzles from the series of nozzles, the method comprising the following steps:

• projecting a first coating product jet by means of the rotating projector, only the air jet nozzles of the first group of nozzles being supplied with air, said air ejection nozzles ejecting first jets of air forming together a first conformation air conforming the first coat of coating product in a narrow manner, and
• before or after the step of projecting a first coating product jet, projecting a second coating product jet by means of the rotating projector, only the air jet nozzles of the second group of nozzles being fed in air, said air ejection nozzles ejecting second air jets together forming a second conformation air conforming the second coating product jet broadly.

• le procédé comprend, entre l'étape de projection du premier jet de produit de revêtement et l'étape de projection du deuxième jet de produit de revêtement, une étape de remplacement de l'organe de pulvérisation par un autre organe de pulvérisation,
• le premier jet de produit de revêtement est projeté sur une première surface étroite et le deuxième jet de produit de revêtement est projeté sur une deuxième surface large,
• le premier jet de produit de revêtement est projeté sur un premier objet de petites dimensions et le deuxième jet de produit de revêtement est projeté sur un deuxième objet de grandes dimensions, et
• lors de la projection du premier jet de produit de revêtement, le projecteur rotatif est équipé d'un organe de pulvérisation mixte et, lors de la projection du deuxième jet de produit de revêtement, le projecteur rotatif est équipé du même organe de pulvérisation mixte.

According to particular embodiments of the invention, the method of recovery also has one or more of the following characteristics, taken separately or in any combination (s) technically possible (s):

• the method comprises, between the step of spraying the first coating product jet and the step of projecting the second coating product jet, a step of replacing the atomizer member with another spray member,
• the first coating product jet is projected onto a first narrow surface and the second coating product jet is projected onto a second wide surface,
• the first coating product jet is projected onto a first small object and the second coating product jet is projected onto a second large object, and
• during the projection of the first coating product jet, the rotating projector is equipped with a mixed spray member and, during the projection of the second coating product jet, the rotating projector is equipped with the same mixed spray member.

• la Figure 1 est une vue en perspective d'une installation de revêtement selon l'invention,
• la Figure 2 est une vue en coupe axiale d'un projecteur rotatif de l'installation de revêtement de la Figure 1, selon un premier mode de réalisation de l'invention,
• la Figure 3 est une vue de dessus de la jupe du projecteur rotatif de la Figure 2, le plan de coupe de la Figure 2 étant matérialisé par la ligne marquée II sur cette Figure,
• la Figure 4 est une vue de dessus de la jupe d'un projecteur rotatif de l'installation de revêtement de la Figure 1, selon un deuxième mode de réalisation de l'invention,
• la Figure 5 est un schéma illustrant une première variante d'un premier exemple de réalisation d'un système d'alimentation en air de l'installation de revêtement de la Figure 1,
• la Figure 6 est un schéma illustrant une deuxième variante du système d'alimentation en air de la Figure 5,
• la Figure 7 est un schéma illustrant une troisième variante du système d'alimentation en air de la Figure 5, et
• la Figure 8 est un schéma illustrant un deuxième exemple de réalisation du système d'alimentation en air de l'installation de revêtement de la Figure 1.

Other characteristics and advantages of the invention will emerge more clearly on reading the description which follows, given solely by way of example and with reference to the appended drawings, in which:

• the Figure 1 is a perspective view of a coating plant according to the invention,
• the Figure 2 is an axial sectional view of a rotating projector of the coating plant of the Figure 1 according to a first embodiment of the invention,
• the Figure 3 is a top view of the skirt of the rotating projector of the Figure 2 , the cutting plane of the Figure 2 being marked by the marked line II in this Figure,
• the Figure 4 is a top view of the skirt of a rotating projector of the coating plant of the Figure 1 according to a second embodiment of the invention,
• the Figure 5 is a diagram illustrating a first variant of a first embodiment of an air supply system of the coating plant of the Figure 1 ,
• the Figure 6 is a diagram illustrating a second variant of the air supply system of the Figure 5 ,
• the Figure 7 is a diagram illustrating a third variant of the air supply system of the Figure 5 , and
• the Figure 8 is a diagram illustrating a second embodiment of the air supply system of the coating plant of the Figure 1 .

The coating plant 2 shown on the Figure 1 is intended for spraying a coating product on a surface to be coated. It comprises, in known manner, a multi-axis sprayer robot 4 and an electropneumatic control cabinet 6 for controlling the robot 4.

The spraying robot 4 comprises an articulated arm 8, a wrist 9 mounted at one end of the articulated arm 8, and a rotating projector 10 attached to the wrist 9.

With reference to the Figure 2 , the rotating projector 10 comprises a spraying member 12, a body 14, a system 16 for driving the spraying member 12 in rotation about an axis AA 'with respect to the body 14, a feed system 18 of the spraying member 12 in coating product, and a skirt 20 covering the outside of the body 14.

• « axial » désigne des éléments orientés parallèlement à l'axe A-A',
• « radial » désigne des éléments orientés perpendiculairement à l'axe A-A', et
• « orthoradial désigne des éléments orientés orthogonalement à l'axe A-A' et perpendiculairement à une direction radiale.

In the following, the terms of orientation are to be understood as follows:

• "Axial" designates elements oriented parallel to the axis A-A ',
• "Radial" means elements oriented perpendicular to the axis A-A ', and
• "Orthoradial means elements oriented orthogonally to the axis AA 'and perpendicular to a radial direction.

Furthermore, the terms "upstream" and "downstream" are to be understood in reference to the direction of flow of the coating product through the rotating projector 10.

The spraying member 12 has a symmetry of revolution, that is to say that there exists an axis, referred to as the axis of the first spraying member, such as any image of the spraying member 12 obtained by rotation of the spraying member 12 around said axis, whatever the angle of this rotation, is identical to the spraying member 12.

The spraying member 12 has a distribution surface 22, oriented towards the axis of the first spraying member, which flares from a bottom 24 of the spraying member 12, close to the body 14, to a ridge 26, remote from the body 14 and defining a downstream end of the spray member 12 opposite the body 14.

The edge 26 is substantially circular and has a diameter, hereinafter referred to as "diameter of the spray member 12".

The spray member 12 also has an outer surface 28 facing away from the axis of the first spray member. This outer surface 28 also flattens, in the example shown, from the bottom 24 to the edge 26. The spraying member 12 thus has a general shape of a bowl and will, therefore, designated in the continuation under the term of "bowl".

The bottom 24 has a coating substance introduction orifice 30, fluidly connected to the supply system 18. A distributor 31 is secured to the bowl 12, facing the orifice 30, so as to channel and distribute the coating product. on the distribution area 22.

In the example shown, the bowl 12 is mounted on the body 14 so that its axis is substantially coaxial with the axis of rotation AA 'and so as to be connected to the drive system 16, so that the system drive 16 can drive the bowl 12 in rotation about the axis A-A '. Advantageously, the bowl 12 is connected to the drive system 16 by means of a reversible connection member (not shown) identical to that described in the patent FR 2,868,342 , the contents of which should be considered as part of this application.

In the example shown, the bowl 12 is a mixed spraying device, that is to say adapted for the projection of the coating product both in wide jet and narrow jet. For this purpose, the diameter of the bowl 12 is preferably between 30 and 90 mm, advantageously between 50 and 65 mm.

Alternatively (not shown), the bowl 12 is adapted only for the projection of the narrow jet coating product. The rotating projector 10 also then comprises a second spraying member, separated from the body 14 and identical to the bowl 12 except for its diameter which, for this second spraying member, is greater than the diameter of the bowl 12.

The body 14 is attached to the wrist 9 of the spray robot 4.

The drive system 16 is typically formed by a compressed air turbine. Alternatively, the drive system 16 is formed by an electric motor.

The feed system 18 is fluidly connected to a source (not shown) of coating material, typically a paint, and is adapted to drive this coating material to the feed port 30 of the bowl 12.

The skirt 20 is fixed relative to the body 14 and covers at least partly an outer surface of the body 14. In addition, in the example shown, the skirt 20 radially surrounds the bottom 24 of the bowl 12, so that the bowl 12 is partially inserted into the skirt 20.

The skirt 20 has a plurality of air ejection nozzles 40, 42, 44, 46 formed in said skirt 20.

Each nozzle 40, 42, 44, 46 is formed in a planar radial surface 32 of said skirt 20. This radial surface 32 is, in the example shown, common to all the nozzles 40, 42, 44, 46, and forms a downstream end of the skirt 20. Alternatively (not shown), at least one of the nozzles 40, 42, 44, 46 is formed in a radial surface axially offset relative to another radial surface in which is formed at least one other nozzles 40, 42, 44, 46.

Alternatively, at least one of the nozzles 40, 42, 44, 46 is formed on a three-dimensional surface of any revolution around A-A '.

The air ejection nozzles 40, 42, 44, 46 communicate fluidly with air supply chambers 40A, 42A, 44A, 46A of said air ejection nozzles 40, 42, 44, 46, each of which is formed. in the rotating projector 10. In particular, each of these feed chambers 40A, 42A, 44A, 46A is, in the example shown, formed in the skirt 20. As a variant, at least one of these feed chambers 40A , 42A, 44A, 46A is formed at the interface between the skirt 20 and the body 14. In another variant, at least one of these feed chambers 40A, 42A, 44A, 46A is formed in the body 14.

Each air ejection nozzle 40, 42, 44, 46 is preferably constituted by a through orifice formed in the skirt 20. In the example shown, this through orifice opens, at a first end, into the radial surface 32 and, at a second end, in the air supply chamber 40A, 42A, 44A, 46A of said air ejection nozzle 40, 42, 44, 46. In a variant, each ejection nozzle of FIG. 40, 42, 44, 46 is constituted by an insert on the skirt 20.

For the sake of simplicity, only a portion of these air nozzles 40, 42, 44, 46 are shown in the Figures, in particular on the Figures 3 and 4 .

The air ejection nozzles 40, 42, 44, 46 comprise four series of nozzles 41, 43, 45, 47 distinct, each series of nozzles, respectively 41, 43, 45, 47, being constituted by a plurality of nozzles, respectively 40, 42, 44, 46, fluidically connected to a common supply chamber, respectively 40A, 42A, 44A, 46A, specific to said series of nozzles 41, 43, 45, 47. The Series of nozzles 41, 43, 45, 17 thus comprise a first series of primary nozzles 41, constituted by first primary nozzles 40 fluidly connected to a first primary chamber 40A, a first series of secondary nozzles 43, constituted by first secondary nozzles 42 fluidically connected to a first secondary chamber 42A, a second series of primary nozzles 45, constituted by second primary nozzles 44 fluidly connected to a second primary chamber 44A, and a second series of secondary nozzles 47, constituted by second secondary nozzles 46 fluidically connected to a second secondary chamber 46A.

With reference to Figures 3 and 4 , the first primary and secondary nozzles 40, 42 are, in the example shown, disposed on an inner ring 50, and the second primary and secondary nozzles 44, 46 are disposed on an outer ring 52. The first primary and secondary nozzles 40 , 42 will therefore in the following also be referred to as "internal air ejection nozzles", and the second primary and secondary nozzles 44, 46 will also be referred to as "external air ejection nozzles".

The inner and outer rings 50, 52 are substantially concentric and both have substantially centrally the axis of rotation A-A '. The inner ring 50 is placed inside a separation perimeter 54 and the outer ring 50 is placed outside this separation perimeter 54, so that the outer ring 52 radially surrounds the inner ring 50.

The separation perimeter 54 is convex, that is, for any pair of points belonging to the perimeter 54, there is no point of the perimeter 54 interposed between the rope segment connecting said two points and the axis A-A '. In particular, the separation perimeter 54 is, as shown, substantially circular. Moreover, the separation perimeter 54 is substantially centered on the axis A-A '.

Each of the inner and outer rings 50, 52 is delimited, on the side of the axis A-A ', by an inner perimeter and, on the opposite side to the axis A-A', by an outer perimeter. The separation perimeter 54 constitutes the outer perimeter of the inner ring 50, and the inner perimeter of the outer ring 52. The inner perimeter 56 of the inner ring 50 is constituted by a convex perimeter flush with at least a portion of the ejection nozzles indoor air 40, 42; it is preferably circular. The outer perimeter 58 of the outer ring 52 is constituted by a convex perimeter flush with at least a portion of the outer air ejection nozzles 44, 46; it is preferably also circular.

Each of the air ejection nozzles 40, 42, 44, 46 is at a distance from the axis of rotation A-A 'taken as the distance from the center of the nozzle 40, 42, 44, 46 to 'axis of rotation A-A', greater than or equal to the half-diameter of the edge 26. In particular, the inner ring 50 has a minimum radial distance d to the axis of rotation A-A ', constituted by the distance radial minimum of the inner perimeter 56 to the axis of rotation A-A ', greater than or equal to the half-diameter of the edge 26 of the bowl 12.

Each of the first primary nozzles 40 is adapted to eject a first primary air jet in a first primary direction defined by a first primary unit vector 60 having a first primary axial component 60A, a first primary radial divergence component 60B, and a first primary orthoradial component 60C.

By "unit vector", it is understood that the vector 60 has a norm, equal to the square root of the sum of the squares of the axial components 60A, 60B of the radial divergence and orthoradial 60C, substantially equal to 1, some of said components 60A, 60B, 60C being zero. The radial divergence component 60B is a relative value counted positively when the vector 60 is oriented away from the axis of rotation A-A ', and negatively when the vector 60 is oriented towards the axis of rotation A-A . These definitions also apply to the other vectors described as unitaries in the following.

Preferably, the first axial and orthoradial primary components 60A, 60C are each non-zero.

The diameter of the orifices constituting the first primary nozzles 40 is between 0.5 and 1.2 mm.

Each of the first secondary nozzles 42 is adapted to eject a first secondary air jet in a first secondary direction defined by a first secondary unit vector 62 having a first primary axial component 62A, a first primary radial divergence component 62B, and a first primary orthoradial component 62C. The first secondary direction is different from the first primary direction, i.e. at least one of said components 62A, 62B, 62C of the first secondary unit vector 62 is different from the component 60A, 60B, 60C of the first vector corresponding primary unit 60.

In particular, the first secondary orthoradial component 62C is smaller than the first primary orthoradial component 60C. Preferably, the first Secondary orthoradial component 62C is chosen so that the angle formed in an orthoradial plane between the first secondary unit vector 66 and the axial direction passing through the first secondary nozzle 42 is less than 30 °.

Advantageously, the positions of the first primary nozzles 40 and the first secondary nozzles 42, as well as the components 60A, 60B, 60C of the first primary unit vector 60 and the components 62A, 62B, 62C of the first secondary unit vector 62, are chosen so that that the first primary and secondary directions are substantially intersecting one another in a first intersection region (not shown) located upstream of the edge 26

The diameter of the orifices constituting the first secondary nozzles 42 is between 0.5 and 1.2 mm.

The first primary and secondary nozzles 40, 42 are alternately arranged relative to one another, that is, for any pair of adjacent first primary nozzles 40, there is a first secondary nozzle 42 angularly interposed between said nozzles 40, and vice versa. The first primary and secondary nozzles 40, 42 are thus in equal numbers.

In the first embodiment, shown in the Figures 2 and 3 , the first primary and secondary nozzles 40, 42 are arranged on different contours 61, 63, said contours 61, 63 being substantially centered on the axis AA 'and being homotheties of each other, the first primary nozzles 40 being offset radially towards the axis AA 'relative to the first secondary nozzles 42. In a variant, the first primary and secondary nozzles 40, 42 are arranged on the same contour 68, substantially centered on the axis A-A', as in the second embodiment.

Each of the second primary nozzles 44 is adapted to eject a second primary air jet along a second primary direction defined by a second primary unit vector 64 having a second primary axial component 64A, a second primary radial divergence component 64B, and a second primary orthoradial component 64C.

Preferably, the second axial and orthoradial primary components 64A, 64C are each non-zero.

The diameter of the orifices constituting the second primary nozzles 44 is between 0.5 and 1.2 mm.

Each of the second secondary nozzles 46 is adapted to eject a second secondary jet of air in a second secondary direction defined by a second secondary unit vector 66 having a second axial component. secondary 66A, a second secondary radial divergence component 66B, and a second secondary orthoradial component 66C. The second secondary direction is different from the second primary direction, i.e. at least one of the components 66A, 66B, 66C of the second secondary unit vector 66 is different from the component 64A, 64B, 64C of the second vector corresponding primary unit 64.

In particular, the second secondary orthoradial component 66C is smaller than the second primary orthoradial component 64C. Preferably, the second secondary orthoradial component 66C is chosen such that the angle formed in an orthoradial plane between the second secondary unit vector 66 and the axial direction passing through the second secondary nozzle 46 is less than 30 °.

Advantageously, the positions of the second primary nozzles 44 and the second secondary nozzles 46, as well as the components 64A, 64B, 64C of the second primary unit vector 64 and the components 66A, 66B, 66C of the second secondary unit vector 66, are chosen so that that the second primary and secondary directions are substantially intersecting one another in a second intersection region (not shown) located upstream of the edge 26.

The second primary and secondary nozzles 44, 46 are alternately arranged relative to each other, that is, for any pair of adjacent second primary nozzles 44, there is a second secondary nozzle 46 angularly interposed between said nozzles 44, and vice versa. The second primary and secondary nozzles 44, 46 are thus in equal numbers.

The number of external air ejection nozzles 44, 46 is greater than or equal to the number of inner air ejection nozzles 40, 42.

The diameter of the orifices constituting the second secondary nozzles 66 is between 0.5 and 1.2 mm.

In the first embodiment, the second primary and secondary nozzles 44, 46 are arranged on different contours 65, 67, said contours 65, 67 being substantially centered on the axis AA 'and being homotheties of one of the other, the second primary nozzles 44 being radially offset towards the axis AA 'relative to the second secondary nozzles 46. In a variant, the second primary and secondary nozzles 44, 46 are arranged on the same contour 69, substantially centered on the axis A-A ', as in the second embodiment.

The first series of primary nozzles 41 and the first series of secondary nozzles 43 together constitute a first pair of series 48 adapted so that, when said series 41, 43 are fed simultaneously with air, the first air jets ejected by the nozzles 40, 42 constituting these series 41, 43 together form a first conformation air adapted to conform the coating product jet in a narrow manner. As for the second series of primary nozzles 45 and the second series of secondary nozzles 47, they together constitute a second pair of series 49 adapted so that, when said series 45, 47 are simultaneously supplied with air, the second jets of air ejected by the nozzles 44, 46 constituting these series 45, 47 together form a second conformation air adapted to conform the coating product jet broadly.

For this purpose, the first and second primary directions are different, that is to say that at least one of the components 64A, 64B, 64C of the second primary unit vector 64 is different from the component 60A, 60B, 60C of the first corresponding primary unit vector 60. In particular, the second orthoradial primary component 64C is greater than the first primary orthoradial component 60C, and the second primary radial divergence component 64B is greater than the first primary radial divergence component 60B.

Thus, the first orthoradial primary component 60C is chosen such that the angle formed in an orthoradial plane between the first primary unit vector 60 and the axial direction passing through the first primary nozzle 40 is between 20 ° and 50 °, preferably between 35 ° and 45 °, the first primary radial divergence component 60B being chosen such that the angle formed in a radial plane between the first primary unit vector 60 and the radial direction passing through the first primary nozzle 40 is substantially equal to 90 °, while the second orthoradial primary component 64C is chosen such that the angle formed in an orthoradial plane between the second primary unit vector 64 and the axial direction passing through the second primary nozzle 44 is between 40 ° and 80 ° , preferably between 50 ° and 60 °, the second primary radial divergence component 64B being chosen so that the angle formed in a radial plane in the second primary unit vector 64 and the radial direction passing through the second primary nozzle 44 is less than 85 ° and preferably between 75 ° and 85 °.

In addition to the robot 4 and the cabinet 6, the coating installation 2 comprises, as shown in FIGS. Figures 5 to 8 , a system 70 for supplying the nozzles 40, 42, 44, 46 in air.

This feed system 70 comprises, according to a first exemplary embodiment shown on the Figures 5 to 8 , an air source 72, a primary channel 74 for supplying the primary air nozzles 40, 44 with air, specific to said primary air nozzles 40, 44, a secondary channel 76 for supplying the air nozzles secondary 42, 46 in air, specific to said secondary air nozzles 42, 46, a first primary valve 80 for regulating the supply of the first primary nozzles 40 with air, a first secondary valve 82 for regulating the supply of the first secondary nozzles 42 with air, a second valve primary 84 to regulate the supply of the second primary nozzles 44 in air, and a second secondary valve 86 to regulate the supply of the second secondary nozzles 46 in air.

The air source 72 is typically an air compressor.

The primary channel 74 comprises a first primary branch 90 specific to the first primary nozzles 40 and a second primary branch 94 specific to the second primary nozzles 44. The first primary branch 90 is equipped with the first primary valve 80 so that said valve 80 regulates the flow of air flowing in the first primary branch 90. The second primary branch 94 is equipped with the second primary valve 84 so that said valve 84 regulates the flow of air flowing in the second primary branch 94.

In the first variant of the Figure 5 , the primary channel 74 consists of said specific branches 90, 94. Each of the valves 80, 84 is then constituted by a variable valve.

In the second and third variants of Figures 6 and 7 the primary channel 74 also comprises a branch 91 common to all the primary air nozzles 40, 44, extending between the source 72 and each of the specific branches 90, 94. This common branch 91 is equipped with a primary valve common 93, preferably constituted by a variable valve, adapted to regulate the flow of air flowing in the common branch 91. The valves 80, 84 are then constituted by all or nothing valves. This makes it possible, in comparison with the first variant, to simplify the management of the air supply at the PLC level, to reduce the number of pipes entering the rotating projector 10, and to reduce the material and integration cost.

The secondary channel 76 comprises a first secondary branch 92 specific to the first secondary nozzles 42 and a second secondary branch 96 specific to the second secondary nozzles 46. The first secondary branch 92 is equipped with the first secondary valve 82 so that said valve 82 regulates the flow of air flowing in the first secondary branch 92. The second secondary branch 96 is equipped with the second secondary valve 86 so that said valve 86 regulates the flow of air flowing in the second secondary branch 96.

In the first variant of the Figure 5 the secondary channel 76 consists of said specific branches 92, 96. Each of the valves 82, 86 is then constituted by a variable valve.

In the second and third variants of Figures 6 and 7 the secondary channel 76 also comprises a branch 95 common to all the secondary air nozzles 42, 46, extending between the source 72 and each of the specific branches 92, 96. This common branch 95 is equipped with a primary valve common 97, preferably constituted by a variable valve, adapted to regulate the flow of air flowing in the common branch 95. The valves 82, 86 are then constituted by all or nothing valves. This makes it possible, in comparison with the first variant, to simplify the management of the air supply at the PLC level, to reduce the number of pipes entering the rotating projector 10, and to reduce the material and integration cost.

The valves 80, 82, 84, 86 are preferably integrated with the rotating projector 10, in particular with the skirt 20. In a variant, the valves 80, 82, 84, 86 are integrated in the articulated arm 8, or in the cabinet of electropneumatic control 6.

The coating installation 2 also comprises a system 100 for controlling the supply system 70. This control system 100 is adapted to control each of the valves 80, 82, 84, 86.

The control system 100 preferably comprises two separate control modules 102, 104: a first control module 102 for controlling the supply of the first air nozzles 40, 42, and a second control module 104 for controlling the supplying the second air nozzles 44, 46, as in the third variant shown in FIG. Figure 7 . The first control module 102 is then adapted to simultaneously control the valves 80 and 82 but not the valves 84 and 86, and the second control module 104 is adapted to simultaneously control the valves 84 and 86 but not the valves 80 and 82.

Each of the control modules 102, 104 has a connection for a control member (not shown) and is adapted to actuate the valves 80, 82, 84, 86 which it controls when said control member is connected to said connection. For example, the control member is a pneumatic actuator, the control module 102, 104 then comprising a pneumatic circuit connecting the connection of said module 102, 104 to the valves 80, 82, 84, 86 controlled by said module 102, 104, said valves 80, 82, 84, 86 then being constituted by pneumatically controlled valves. In a variant, the control member is a hydraulic actuator, the control module 102, 104 then comprising a hydraulic circuit connecting the connection of said module 102, 104 to the valves 80, 82, 84, 86 controlled by said module 102, 104, said valves 80, 82, 84, 86 then being constituted by hydraulically controlled valves. In another variant, the control member is an electric actuator, the control module 102, 104 then comprising an electrical circuit connecting the connection of said module 102, 104 to the valves 80, 82, 84, 86 controlled by said module 102, 104 said valves 80, 82, 84, 86 then being constituted by electrically controlled valves.

Having thus common control modules 102, 104 for several valves 80, 82, 84, 86 makes it possible to reduce the number of control connections, as well as perfect synchronization of the control of the first valves 80, 82 of one side and second valves 84, 86 on the other hand.

Alternatively, the control system 100 comprises a control module 110, 112, 114, 116 specific for each of the valves 80, 82, 84, 86, as in the second variant shown in FIG. Figure 6 . Each of these control modules, respectively 110, 112, 114, 116, is then adapted to control only one valve, respectively 80, 82, 84, 86.

Each of the control modules 110, 112, 114, 116 has a branch for a control member (not shown) and is adapted to actuate the valve 80, 82, 84, 86 which it controls when said control member is connected to said connection. For example, the control member is a pneumatic actuator, the control module 110, 112, 114, 116 then comprising a pneumatic circuit connecting the connection of said module 110, 112, 114, 116 to the valve 80, 82, 84, 86 controlled by said module 110, 112, 114, 116, said valve 80, 82, 84, 86 then being constituted by a pneumatically controlled valve. In a variant, the control member is a hydraulic actuator, the control module 110, 112, 114, 116 then comprising a hydraulic circuit connecting the connection of said module 110, 112, 114, 116 to the valve 80, 82, 84, 86 controlled by said module 110, 112, 114, 116, said valve 80, 82, 84, 86 then being constituted by a hydraulically controlled valve. In another variant, the control member is an electric actuator, the control module 110, 112, 114, 116 then comprising an electrical circuit connecting the connection of said module 110, 112, 114, 116 to the valve 80, 82, 84 , 86 controlled by said module 110, 112, 114, 116, said valve 80, 82, 84, 86 then being constituted by an electrically controlled valve.

This variant allows a greater flexibility in the control of the valves 80, 82, 84, 86, and therefore in the use of the air nozzles 40, 42, 44, 46, and allows in In particular, the primary inner nozzles 40 may be used simultaneously with the primary outer nozzles 44 and / or the secondary inner nozzles 42 with the secondary outer nozzles 46 and / or the inner primary nozzles 40 with the secondary outer nozzles 46 and / or the inner nozzles. with the primary outer nozzles 44 and / or the inner primary nozzles 40 with the secondary inner nozzles 42 and / or the primary outer nozzles 44 with the secondary outer nozzles 46.

With reference to the Figure 8 , the power supply system 70 according to the second embodiment differs from the first embodiment in that it does not include a primary supply path of the primary air nozzles 40, 44 in air, specific to said nozzles primary air 40, 44, and no secondary supply path of the secondary air nozzles 42, 46 with air, specific to said secondary air nozzles 42, 46, nor of clean valve for each of the series of nozzles 41, 43 , 45, 47. Instead, the power supply system 70 comprises a first feed channel 120, specific to the first pair of series 48, a second feed path 122, specific to the second pair of series 49, a first valve 124 for regulating the supply of the first pair of series 48 in air, and a second valve 126 for regulating the supply of the second pair of series 49 in air.

The first primary channel 120 comprises a first primary branch 130 specific to the first primary nozzles 40 and a first secondary branch 132 specific to the first secondary nozzles 42. The first primary branch 130 is equipped with a first primary rate reducer 140, preferably not adjustable, to reduce the flow in the branch 130 downstream of the flow restrictor 140. The first secondary branch 132 is equipped with a first secondary flow restrictor 142, preferably non-adjustable, to reduce the flow in the branch 132 downstream flow reducer 142.

The first channel 120 also comprises a first common branch 131, common to all the first air nozzles 40, 42, extending between the source 72 and each of the specific branches 130, 132. This common branch 131 is equipped with the first valve 124.

The second primary track 122 comprises a second primary branch 134 specific to the second primary nozzles 44 and a second secondary branch 134 specific to the second secondary nozzles 46. The second primary branch 134 is equipped with a second primary flow restrictor 144, preferably not adjustable, to reduce the flow in the branch 134 downstream of the flow restrictor 144. The second secondary branch 136 is equipped with a second secondary flow restrictor 146, preferably non-adjustable, to reduce the flow in the branch 136 downstream of the flow restrictor 146.

The second channel 122 also comprises a second common branch 135, common to all the second air nozzles 40, 42, extending between the source 72 and each of the specific branches 134, 136. This common branch 135 is equipped with the second valve 126.

Each of the first and second valves 124, 126 is advantageously constituted by an on-off valve.

Furthermore, in this second exemplary embodiment, the control system 100 comprises a first control module 154 for controlling the first valve 124, and a second control module 156 for controlling the second valve 126.

Each of the control modules 154, 156 has a branch for a control member (not shown) and is adapted to actuate the valve 124, 126 which it controls when said control member is connected to said branch. For example, the control member is a pneumatic actuator, the control module 154, 156 then comprising a pneumatic circuit connecting the connection of said module 154, 156 to the valve 124, 126 controlled by said module 154, 156, said valve 124 , 126 then being constituted by a pneumatically controlled valve. Alternatively, the control member is a hydraulic actuator, the control module 154, 156 then comprising a hydraulic circuit connecting the connection of said module 154, 156 to the valve 124, 126 controlled by said module 154, 156, said valve 124 , 126 then being constituted by a hydraulically controlled valve. In another variant, the control member is an electric actuator, the control module 154, 156 then comprising an electrical circuit connecting the connection of said module 154, 156 to the valve 124, 126 controlled by said module 154, 156, said valve 124, 126 then being constituted by an electrically controlled valve.

A method of covering an object (not shown), typically a motor vehicle body, with the coating product, by means of the coating plant 2, will now be described.

The coating installation 2 is first provided with the bowl 12 mounted on the body 14. A first narrow surface, constituting for example the edge of a roof of the bodywork, is then placed facing the rotating projector 10 and the control module 102 (or 154 if it is in the second embodiment) is actuated, so as to open the supply of the inner air nozzles 40, 42 in air.

The rotating projector 10 is then activated, that is to say that the supply system 18 is turned on, and that the variable valves 93, 97 are open to allow the supply of the air nozzles 40, 42 in air. The rotating projector 10 then starts to project a jet of coating product which, thanks to the air ejected by the inner nozzles 40, 42, is shaped in a narrow manner. The narrow surface can thus be covered without wasting coating product.

Once the narrow surface is covered, the rotating projector 10 is deactivated, and is placed in front of the rotating projector a second extended surface of the object, for example the center of the roof of the body. The control module 102 (or 154 if it is in the second embodiment) is then deactivated so as to close the supply of the air nozzles 40, 42 in air, and the control module 104 (or 156 if it is in the second embodiment) is actuated to open the supply of the outside air nozzles 44, 46 in air, the bowl 12 remaining mounted on the body 14. Alternatively, in the when the bowl 12 is adapted only for the projection of the narrow jet coating product, the bowl 12 is removed from the body 14 and replaced by the second pulverizer of diameter greater than that of the bowl 12.

Once these changes are made, the rotating projector 10 is reactivated. The jet of coating product projected by the rotating projector 10 is then shaped broadly by the air ejected by the outer nozzles 44, 46. The extended surface can thus be covered quickly and with a high quality of recovery.

When it is desired to return to a stream of narrow coating product, the rotary projector 10 is deactivated, the control module 104 (or 156 if it is in the second embodiment) is deactivated so as to close the supplying the outside air nozzles 44, 46 with air, and operating the control module 102 (or 154 if it is in the second embodiment) so as to open the supply of the interior air nozzles 40 , 42 in air, the rotating projector 10 then being reactivated.

Note that it is also possible to coat, by means of the method described above, various objects, some large and some small, the adjustment of the width of the jet being made when passing from a small object to a large object, and vice versa.

Thanks to the invention described above, it is thus possible to produce wide and narrow coating product jets with the same rotating projector, which gives a very great flexibility in the use of this rotating projector.

It will be noted that, although the description given above is reduced to the case in which the series of nozzles 41, 43, 45, 47 are four in number, the invention is not limited to this embodiment alone, and also extends to all cases in which the series of nozzles 41, 43, 45, 47 are at least three in number, the pairs of series 48, 49 sharing, in the case where the series of nozzles 41, 43, 45, 47 are three in number, a series of common nozzle.

It should also be noted that, rather than being grouped in pairs, as described above, the nozzle series 41, 43, 45, 47 can be grouped into groups of three series 41, 43, 45, 47 or more. to form a conformation air, and / or some of the series 41, 43, 45, 47 may be isolated from the others to form a conformation air.

It will further be noted that although the description given above is reduced to the case where the first nozzles 40, 42 are disposed within a separation perimeter 54, the second nozzles 44, 46 being disposed at the outside this separation perimeter 54, the invention is not limited to this single embodiment, and extends to all the relative positions of the nozzles 40, 42, 44, 46 possible, especially at the positions for which the second nozzles 44, 46 are arranged inside a separation perimeter, the first nozzles 40, 42 being disposed outside this separation perimeter, and at the positions for which the first and second nozzles 40, 42, 44, 46 are arranged on a common contour.

Claims (15)

A skirt (20) for a rotating coating product projector (10) for projecting a coating material jet onto a surface to be covered, the skirt (20) having a plurality of air jet nozzles (40, 42 , 44, 46) formed in said skirt (20) for ejecting air streams forming a conformation air adapted to form the coating product stream,
characterized in that the air ejection nozzles (40, 42, 44, 46) comprise at least three separate sets of nozzles (41, 43, 45, 47), each set of nozzles (41, 43, 45, 47) consisting of a plurality of air ejection nozzles (40, 42, 44, 46) fluidly connected to a common supply chamber (40A, 42A, 44A, 46A) specific to said series of nozzles ( 41, 43, 45, 47). The skirt (20) according to claim 1, wherein the air ejection nozzles (40, 42, 44, 46) comprise a first group of nozzles (48), consisting of at least a first set of nozzles (41, 43) of the plurality of nozzles (41, 43, 45, 47), and a second group of nozzles (49) consisting of at least a second series of nozzles (45, 47) out of the series of nozzles (41, 43). , 45, 47), the first group of nozzles (48) being such that when the or each first set of nozzles (41, 43) is supplied with air, the nozzles (40, 42) of the or each first set of nozzles nozzles (41, 43) eject first air streams together forming a first conformation air adapted to closely conform the coating product stream, and the second group of nozzles (49) being such that when the or each second series of nozzles (45, 47) is supplied with air, the nozzles (44, 46) of the or each second series of nozzles (45, 47) eject second air jets forming emble a second conformation air adapted to conform the coating product jet broadly. The skirt (20) of claim 2, wherein the or each first set of nozzles (41, 43) is separate from the or each second set of nozzles (45, 47). A skirt (20) according to claim 2 or 3, wherein the first group of nozzles (48) comprises a first series of primary nozzles (41), consisting of first primary nozzles (40) each adapted to eject a first stream of air in a first primary direction, and the second group of nozzles (49) comprises a second series of primary nozzles (45), distinct from the first series of primary nozzles (41) and consisting of second primary nozzles (44) each adapted to ejecting a second primary air jet in a second primary direction different from the first primary direction. The skirt (20) of claim 4, wherein the first primary direction is defined by a first primary unit vector (60) having a first primary radial divergence component (60B), and the second primary direction is defined by a second unit vector primary (64) having a second primary radial divergence component (64B), the second primary radial divergence component (64B) being greater than the first primary radial divergence component (60B). The skirt (20) of claim 4 or 5, wherein the first primary direction is defined by a first primary unit vector (60) having a first primary orthoradial component (60C), and the second primary direction is defined by a second unit vector primary (64) having a second primary orthoradial component (64C), the second primary orthoradial component (64C) being greater than the first primary orthoradial component (60C). The skirt (20) according to any one of claims 4 to 6, wherein each of the first and second primary directions is defined by a primary unit vector (60, 64) having a non-zero primary orthoradial component (60C, 64C). A skirt (20) according to any one of claims 4 to 7, wherein the first group of nozzles (48) comprises a first series of secondary nozzles (43), distinct from the first and second series of primary nozzles (41, 45) , and the second group of nozzles (49) comprises a second series of secondary nozzles (47), distinct from the first and second series of primary nozzles (41, 45). Skirt (20) according to claim 8, wherein the first nozzles (40, 42) of the first series of primary and secondary nozzles (41, 43) are arranged alternately with respect to each other, and / or the second nozzles ( 44, 46) of the second series of primary and secondary nozzles (45, 47) are alternately arranged relative to one another. A skirt (20) according to any one of claims 4 to 9, wherein the first nozzles (40, 42) are disposed within a separation perimeter (54), the second nozzles (44, 46) being disposed outside the separation perimeter (54), or the first nozzles (40, 42) are disposed outside a separation perimeter (54), the second nozzles (44, 46) being disposed at the inside the separation perimeter (54). Rotating projector (10) for coating material, comprising at least one coating material spraying member (12), a drive system (16) for driving the first spraying member (12) in rotation about an axis (A-A '), and a fixed skirt (20),
characterized in that the skirt (20) is constituted by a skirt according to any one of the preceding claims, each of the supply chambers (40A, 42A, 44A, 46A) being formed in the rotating projector (10). Rotary projector (10) according to claim 11, wherein the atomizer member (12) has at least one generally circular edge (26), each of the air jet nozzles (40, 42, 44, 46) being at a distance from the axis of rotation (A-A ') greater than or equal to the half-diameter of the edge (26). A spray robot (4) comprising an articulated arm (8), a wrist (9) mounted at one end of the articulated arm (8), and a rotatable projector (10) attached to the wrist (9), wherein the rotating projector (8) 10) is a rotating projector according to claim 11 or 12. A method of covering at least a portion of at least one object with a projected coating material by means of a rotatable projector (10) according to claim 11 or 12, wherein the air ejection nozzles (40) , 42, 44, 46) comprise a first group of nozzles (48), consisting of at least a first series of nozzles (41, 43) among the series of nozzles (41, 43, 45, 47), and a second group nozzle arrangement (49) consisting of at least a second series of nozzles (45, 47) out of the series of nozzles (41, 43, 45, 47), the method comprising the steps of: - projecting a first coating product stream by means of the rotating projector (10), only the air ejection nozzles (40, 42) of the first group of nozzles (48) being supplied with air, said nozzles ejection of air (40, 42) ejecting first air jets together forming a first conformation air conforming the first coating product jet in a narrow manner, and before or after the step of projecting a first coating product jet, projecting a second coating product jet by means of the rotating projector (10), only the air ejection nozzles (44, 46) of the second group of nozzles (49) being supplied with air, said air ejection nozzles (44, 46) ejecting second air jets together forming a second conformation air conforming to the second coating product jet; in a broad way. A method of coating according to claim 14, comprising, between the step of projecting the first coating material jet and the projecting step of second coating product jet, a step of replacing the spray member (12) by another spray member.

Images