Rotary atomizer including rotary bowl and magnetic coupling means and assembly and / or disassembly method of the same

Abstract

To provide a rotary atomizer for a coating product which enables easy attachment of an air supply skirt and a bowl to a main body and enables automation.SOLUTION: An atomizer (2) of the invention includes: a main body (4); and a bowl (8) which is rotated around a rotation axis (A2) defined by the main body by a rotary member (10). The bowl includes first magnetic coupling means (82) and has a tendency to cooperate with consistent second magnetic coupling means (14) fixed to a non-rotary portion (6) of the atomizer (2). The first coupling means and the second coupling means have a tendency to apply force at least partially acting in an axial direction relative to the rotation axis (A2) of the bowl (8). The force induces rotational coupling of the bowl to the rotary member. The second magnetic coupling means (14) is supported by an air supply skirt (6) directly attached onto the main body (4).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotary atomizer for coating products, comprising a main body and a bowl rotated about an axis of rotation defined by the main body, and further to a method for assembling and / or disassembling such an atomizer. [Background technology]

[0002] From WO 2005 / 082542 A1 it is known to mount a bowl on a rotary atomizer by associating first and second magnetic coupling means fixed to the non-rotating parts of the bowl and the atomizer, respectively, which makes it possible to apply a net axial force, for example inducing a rotational coupling between the bowl and a drive member, for example the rotor of a turbine or a shaft driven by such a rotor. Such an arrangement is generally sufficient.

[0003] On the other hand, it is known to provide rotary atomizers with an air supply skirt, which serves to distribute an air flow in the vicinity of the bowl for guiding or shaping the cloud of droplets of the coating product emerging from the edge of the bowl. In this case, the second magnetic coupling means is often arranged in the central part of the main body of the atomizer, facing a central opening of the air supply skirt. The bowl is engaged in this central opening so as to cooperate with the rotation means. In such a case, the air supply skirt has to be mounted on the main body before the bowl is put in place and has to be accurately positioned by hand opposite the second magnetic coupling means. On the other hand, during maintenance operations, the bowl has to be separated from the main body and then the skirt has to be separated from the main body. These separations have to be carried out during two successive manual operations, which are difficult to carry out in environments that are not very suitable for handling, such as, for example, a paint booth.

[0004] Furthermore, in some applications, the bowl is of a relatively modest size and has a narrow grip that introduces a risk of dropping the bowl during manual handling, particularly when disassembling the bowl and air supply skirt, if an operator attempts to work on the skirt prior to removing the bowl, there is a high likelihood of dropping the bowl, which could damage the edge of the bowl. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] WO2005 / 082542A1 [Patent Document 2] WO2005 / 082542A Summary of the Invention [Problem to be solved by the invention]

[0006] In such devices, assembly and disassembly of the bowl and air delivery skirt is a complex operation that is difficult to automate.

[0007] More specifically, the present invention seeks to overcome such shortcomings by proposing a new rotary atomizer for coating products in which the installation of the air supply skirt and bowl on the main body is easy and such installation can be automated to a large extent. [Means for solving the problem]

[0008] To this end, the subject of the present invention relates to a rotary atomizer for coating products, comprising a main body and a bowl rotated by a rotating member about an axis of rotation defined by the main body. The bowl comprises first magnetic coupling means, which tend to cooperate with a matching second magnetic coupling means fixed relative to a non-rotating part of the atomizer for coating products. The first and second coupling means tend to apply a force at least partially axial to the axis of rotation of the bowl, which force induces a rotational coupling of the bowl to the rotating member. The atomizer is characterized in that the second magnetic coupling means is supported by an air supply skirt mounted directly on the main body.

[0009] According to the invention, the first and second magnetic coupling means allow the assembly of the air delivery skirt and bowl into a sub-assembly that can be handled as a unit during installation on the main body or during its own disassembly. The size of the sub-assembly is larger than the size of the bowl alone and therefore easier to grasp. There is also less chance of dropping the sub-assembly. Furthermore, the first and second coupling means ensure that the bowl is accurately positioned relative to the air delivery skirt, so that proper installation of the skirt on the main body ensures that the bowl is properly positioned relative to the main body and thus relative to the rotating member that rotates the bowl.

[0010] In accordance with advantageous but non-essential aspects of the invention, such an atomizer may incorporate one or more of the following features separately or in any technically permitted combination. - the second magnetic coupling means is mounted on or formed by an internal collar flange of the air supply skirt and bears against the forward face of the main body. the first magnetic coupling means are formed by a ferromagnetic part of the bowl and the second magnetic coupling means are formed by at least one permanent magnet; the first magnetic coupling means are formed by at least one permanent magnet and the second magnetic coupling means are formed by a ferromagnetic portion of the air supply skirt; - the atomizer comprises a magneto-pneumatic or magneto-hydraulic system, the magneto-pneumatic or magneto-hydraulic system being a magnetic device for hooking the air supply skirt onto the main body; a pneumatic or hydraulic mechanism for locking and clamping the air supply skirt onto the main body; Equipped with. - the magnetic latching device is configured to apply an axial magnetic force of a first intensity parallel to the longitudinal axis of the atomizer between the air delivery skirt and the main body, and the pneumatic or hydraulic clamping mechanism is configured to apply an axial mechanical force of a second intensity parallel to the longitudinal axis of the atomizer between the air delivery skirt and the main body, the second intensity being strictly higher than the first intensity. - The atomizer includes a seal disposed between the air supply skirt and the main body, the seal being compressed by a mechanical force applied by a pneumatic or hydraulic clamping mechanism to isolate the conduit for circulation of the shaping air from the exterior of the atomizer. The air supply skirt is provided with a screw-fitting relief onto a matching relief formed on the main body. The air delivery skirt is clamped to the main body by a magnetic force applied between a portion of the main body and a portion of the air delivery skirt.

[0011] According to a second aspect, the subject of the invention is a method for assembling and / or disassembling an atomizer for a coating product such as described above, wherein: - When assembling the atomizer, in a first assembly step, the air delivery skirt and the bowl are assembled and held together by magnetic forces between the first magnetic coupling means and the second magnetic coupling means; In a second assembly step, the subassembly formed by the air supply skirt and the bowl is mounted directly onto the main body in one operation; - When disassembling the atomizer, In a first disassembly step, the subassembly formed by the air supply skirt and the bowl is separated from the main body in one operation; In a second disassembly step, the air delivery skirt and bowl are separated from each other against the magnetic force between the first magnetic coupling means and the second magnetic coupling means.

[0012] The invention will be clearer on reading the following description, given solely by way of example and without limitation, and with reference to the drawings, in which: [Brief description of the drawings]

[0013] [Figure 1] 1 is a partially exploded longitudinal cross-sectional view of an atomizer according to a first embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective exploded longitudinal section of a magnetopneumatic system belonging to the atomizer shown in FIG. 1; [Figure 3A] 2) Insert A) showing the atomizer shown in FIG. 1 during the first substep of mounting the subassembly comprising the air supply skirt and bowl on the main body. [Figure 3B] 2B) shows the atomizer shown in FIG. 1 during a first substep of mounting the subassembly comprising the air delivery skirt and the bowl on the main body. Insert B) is an enlarged view of detail B in Insert A). [Figure 4A] 3B is a view similar to FIG. 3A during a second substep of the assembly method. [Figure 4B] 3B during a second substep of the assembly method. FIG. [Figure 5A] 3B is a view similar to FIG. 3A during a third substep of the assembly method. [Figure 5B] 3B during a third substep of the assembly method. FIG. [Figure 6A] 3B is a view similar to FIG. 3A during a fourth substep of the assembly method. [Figure 6B] 3B during a fourth substep of the assembly method. FIG. [Figure 7] 2 is a cross-sectional view similar to FIG. 1 of an atomizer according to a second embodiment of the present invention. [Figure 8] 2 is a cross-sectional view similar to FIG. 1 of an atomizer according to a third embodiment of the present invention. [Figure 9] 1 for an atomizer according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The atomizer 2 for coating products shown in FIGS. 1 to 6B comprises a main body 4 formed by the assembly of an outer part 42, an inner part 44 and a base 46.

[0015] For example, the coating product may be a liquid paint, primer, or varnish intended to be applied to an automotive vehicle body or component.

[0016] The screws 48 secure the main body parts 42, 44 and 46. The screws 48 protrude from the front face 428 of the outer part 42.

[0017] The atomizer 2 is an internally charged electrostatic atomizer, and includes a high voltage unit (not shown) configured to bring the coating product atomized by the atomizer 2 to a given potential.

[0018] A2 denotes the longitudinal axis of the atomizer 2.

[0019] The front side of the atomizer 2 or atomizer component is defined as the side that is oriented toward a workpiece to be coated during use of the atomizer 2, and the rear side is defined as the side that is oriented opposite the front side. In the drawings, the front of the atomizer 2 is oriented upward and the rear is oriented downward.

[0020] In the assembled configuration of the atomizer 2, the air delivery skirt 6 is mounted on the main body 4. The air delivery skirt 6 comprises a skirt body 62 and a sleeve 64 which is threadedly attached to the skirt body 62.

[0021] In one variation, the skirt body 62 and the sleeve are rigidly attached by crimping, welding, and / or bonding.

[0022] The connection between the skirt body 62 and the sleeve 64 is made at the forward end 641 of the sleeve.

[0023] The sleeve 64 is made from a ferromagnetic material, such as, for example, steel.

[0024] Furthermore, an atomizer bowl 8 belongs to the atomizer 2 and is intended to be rotated about a longitudinal axis A2 by a turbine, the rotor of which is indicated with 10. The stator of the turbine is constituted by an internal part 44 of the main body 4.

[0025] The bowl 8 defines a male frusto-conical surface 88 that converges towards the rear, while the rotor 10 defines a female frusto-conical surface 108 that diverges towards the front and generally matches the male frusto-conical surface 88 .

[0026] An annular magnet 14 is supported by an internal radial collar flange 649 of the air supply skirt 6. More precisely, the magnet 14 is disposed in a groove 650 provided in the internal radial collar flange 649 and oriented towards the front of the air supply skirt 6.

[0027] In the configuration in which the bowl 8 is mounted on the air delivery skirt 6, and before the air delivery skirt is mounted on the main body 4, an annular surface 82 of the bowl 8 made from a ferromagnetic material is located opposite a permanent magnet 14, which has the effect of rigidly mounting the parts 6 and 8 together. These rigidly mounted parts 6 and 8 form a subassembly 22 that is unitary and easy to manipulate when being put into place on the atomizer 2 or removed.

[0028] In one variant, as shown in the third embodiment, only the portion of the bowl 8 that defines the annular surface 82 is made from a ferromagnetic material, such as in the form of a steel ring mounted directly on a bowl 8 made from aluminium or the like.

[0029] The ferromagnetic portion of the bowl defining surface 82 forms the first magnetic coupling means. The magnets 14 form the second magnetic coupling means. When the air delivery skirt 6 with the bowl 8 is mounted and fixed on the main body 4, the first magnetic coupling means 82 and the second magnetic coupling means 14 cooperate to press a surface 88 of the bowl 8 against a surface 108 of the rotor 10, thereby fixing the bowl and rotor for rotation about the axis of rotation A2.

[0030] The atomizer 2 further comprises a coating product injector 16 having a downstream end 162 that extends into the central bore 84 of the bowl 8 in a configuration in which the bowl is mounted on the turbine rotor 10.

[0031] A cover 18 is fitted around the main body 4 to protect the main body from splashes of the coating product.

[0032] The skirt body 62 includes a plurality of channels 622 which, in the configuration in which the air delivery skirt 6 is mounted on the main body 4, extend entirely through the skirt body 62 along a direction parallel to the longitudinal axis A2, each channel feeding into an exit orifice 624 through which an air jet can be directed toward the cloud of coating product exiting the edge 86 of the bowl 8, thereby shaping the coating product jet and / or directing the coating product toward the object to be coated. The orifices 624 are formed on a circular forward face 626 of the skirt body 62.

[0033] The skirt body 62 defines a recessed housing 628. In the configuration in which the air delivery skirt 6 is mounted on the main body 4, the front portion of the outer part 42 of the main body 4 is received within this recessed housing 628. The recessed housing 628 is provided on the rear part of the skirt body 62.

[0034] The outer part 42 of the main body 4 comprises a conduit 422 for conveying air towards the air supply skirt 6. The channel 422 is supplied with air by a channel 442 which essentially extends in a plane different from the plane of Figures 1 and 3A to 6B and in which only its downstream end is visible.

[0035] The bottom 628a of the concave housing 628 comprises two annular grooves 628c and 628d serving as dispensers for the supply of the two groups of conduits 622 from the outlets 424 of the conduits 422. To ensure a seal against the passage of air between the conduits 422 and the grooves 628c and 628d, an O-ring 20 is placed in annular groove 426 formed on the front face 428 of the outer part 42 of the main body 4, i.e. in the boundary zone between the main body 4 and the skirt 6. The O-ring 20 is intended to be pressed against the bottom 628a of the concave housing 628.

[0036] In the example shown, the O-rings 20 and annular grooves 426 are concentric and number three. In a variation (not shown), the number and / or shape of the O-rings 20 and annular grooves 426 are different.

[0037] The sleeve 64 is designed to be engaged in a central housing L2 of the atomizer 2, defined radially with respect to the longitudinal axis A2 between the outer part 42 and the inner part 44 of the main body 4.

[0038] 642 denotes the rear edge of the sleeve 64, i.e. the edge of the sleeve on the opposite side of the skirt body 62. 644 denotes the end of the sleeve 64 that is closest to the rear edge 642. The rear edge 642 defines a rear end 644 on the opposite side of the skirt body 62. The rear end 644 is located opposite the front end 641 of the sleeve 64.

[0039] The radially outer surface of the sleeve 64 is designated S64. This radially outer surface is provided with a peripheral groove 646 which forms a concave housing on the exterior of the sleeve 64. 646a denotes the rear edge of the peripheral groove 646, i.e. the edge of the groove which is located closest to the end 644 of the sleeve 64.

[0040] 647 denotes an outer peripheral rib of the sleeve 64 which separates the peripheral groove 646 from the end 644. 647a denotes the rear edge of the rib, i.e. the edge of the rib which is located nearest the end 644 of the sleeve 64.

[0041] To ensure that the subassembly 22 is hung on the main body 4 and that the skirt 6 is clamped on the main body, a magnetic-pneumatic system 100 is provided in the central housing L2. The magnetic-pneumatic system 100 comprises a magnetic hanging device 100A and a pneumatic mechanism 100B for clamping the air supply skirt 6 on the main body 4.

[0042] The latching provided by the magnetic latching device 100A ensures that the air delivery skirt 6 with the bowl 8 remains in place on the main body 4 even when the main body 4 is moved by a multi-axis robot or reciprocator to which the atomizer is attached. This movement of the atomizer can cause an acceleration on the air delivery skirt 6 and the bowl 8, which can have the effect of pushing the sleeve 64 out of the central housing L2. The magnetic latching force is dimensioned to prevent such an acceleration.

[0043] The clamping force makes it possible to determine the positioning of the air supply skirt 6 on the main body 4 and to ensure the sealing of the outlet orifice 624 of the circuit supplying shaped air to the cloud of coating product by compressing the O-ring 20.

[0044] The magneto-pneumatic system 100 extends along a longitudinal axis A100 which coincides with the longitudinal axis A2 of the atomizer 2 in the configuration in which the magneto-pneumatic system 100 is mounted.

[0045] The magnetic-pneumatic system 100 comprises a cap 102 that is secured onto the main body 4 by screws that extend through one or more tabs 102a on the exterior of the cap 102. One of these screws is represented in Figure 2 by its centerline 103.

[0046] The cap 102 defines an annular volume V102 centered about the longitudinal axis A100. The annular volume V102 is bounded by a radially inner wall 102b and a radially outer wall 102c.

[0047] A passage 102d is provided in the thickness of the radially outer wall 102c and serves to fluidly connect the volume V102 with a conduit 446 provided in the inner part 44 of the main body 4.

[0048] On the other hand, the inner wall 102b of the cap 102 terminates in a chamfered edge 102e that is oriented towards the volume V102 and converges towards the longitudinal axis A100, i.e. towards the rear of the cap 102, on the opposite side of the bottom 102f of the volume V102.

[0049] The magnetic-pneumatic system 100 further comprises a cup 104 arranged on the rear bottom of the central housing L2. In the example of the drawing, the bottom of the central housing L2 is located on the opposite side of the front mouth of the central housing L2 and is defined by the internal part 44.

[0050] The magneto-pneumatic system 100 further comprises an annular piston 106 provided with two sealing rings 107a and 107b. In this example, these sealing rings are formed by two O-rings housed in two external and internal peripheral grooves 106a and 106b, respectively, formed on the piston 106. These O-rings 107a and 107b are not shown in FIG. 1 in order to better visualize the grooves 106a and 106b.

[0051] In one variant, the sealing ring is formed by a lip seal. According to another variant, the sealing ring is mounted on a wall of the cap 102 located opposite the piston 106.

[0052] The piston 106 is movable parallel to the coincident axes A2 and A100 and is partially engaged in the volume V102 of the cap 102. With the piston 106 partially engaged in the housing V102 and the seal segments 107a and 107b bearing against the walls 102c and 102b, a variable volume sealed chamber C100 is defined between the elements 102 and 106. The variable volume chamber C100 is supplied with compressed air coming from the conduit 446 through the passage 102d. Means such as a compressed air source, a proportional valve, and a bleed valve (not shown) are used to supply compressed air to or open the variable volume chamber C100 depending on the assembly or disassembly sequence of the skirt 6 on the main body 4. The pressure of the air present in the conduit 446 is controlled independently of the pressure of the air driving the rotor 10 and the pressure of the skirt air in the conduit 442.

[0053] In one variant, part of the air driving the rotor 10 is redirected towards the conduit 446. In such a case, the variable volume chamber C100 can be supplied with compressed air as soon as the turbine is in operation. According to another variant, the conduit 446 can be supplied with compressed air from air used in the atomizer 2 for another function, for example from the skirt air circulating in the conduit 442.

[0054] Additionally, the piston 106 defines a volume V 106 for accommodating a ball 108 which forms a member for engaging the piston 106 in the outer peripheral groove 646 of the sleeve 64 .

[0055] Advantageously, a ball 108 is mounted within each volume V106.

[0056] Each ball 108 is contained within a volume V106 and may or may not protrude from this volume V106 through an opening O106 that forms the outlet of each volume V106 on the inner peripheral surface S106 of the piston 106.

[0057] Each volume V106 is defined, on the opposite side of the opening O106 of that volume V106, by a surface S106 that converges forwards towards the longitudinal axis A100 and is inclined at an angle α with respect to the longitudinal axis, said angle α being non-zero and preferably between 15° and 60°, or preferably between 30° and 50°.

[0058] The surface S106 of each volume V106 forms a cam surface for guiding the ball 108.

[0059] The magnetic-pneumatic system 100 further comprises a support 110. This support 110 has an annular shape centered on a longitudinal axis A100 and is formed by a solid body 110a and a profile 110b made of ferromagnetic material. The parts 110a and 110b of the support 110 are fixed together by suitable means, in particular by bonding, crimping and / or welding.

[0060] In one variation, the support 110 is a single piece.

[0061] The support 110 includes a pin 110c for indicating a fixed position for the piston 106 about the longitudinal axis A100.

[0062] Furthermore, the support 110 comprises a stopper 110d intended to engage from the rear of the piston 106 into the volume V106, thereby holding the ball 108 in a fixed position within said volume.

[0063] The support 110 carries an annular permanent magnet 112 arranged radially inward of the support 110. In this example, the permanent magnet is fixed relative to the profile 110b, for example by bonding.

[0064] On the other hand, the support 110, and more specifically the body 110a of the support 110, defines a first frusto-conical inner surface S110 centered on the longitudinal axis A100 and converging toward the piston 106, and a second frusto-conical inner surface S'110 centered on the longitudinal axis A100 and diverging toward the piston 106.

[0065] The magnetic-pneumatic system 100 further comprises a leaf spring 114 forming a resilient member for returning the piston 106 and preferably the support 110 towards the front.

[0066] The leaf spring 114 is formed from steel blades. The use of a leaf spring such as the one shown in the drawings has the advantage that it allows for a relatively large axial stroke of the piston 106 while minimizing the axial bulk of the spring 114.

[0067] In one variant, the leaf spring 114 may be replaced by other elastic members, in particular by an elastomeric block or a spiral spring.

[0068] Next, a method of assembling the atomizer 2 will be described.

[0069] In a first step, the subassembly 22 is formed by engaging the bowl 8 in the central opening O6 of the air supply skirt 6 until the magnet 14 and surface 82 provide a magnetic clamping fixation between the elements 6 and 8. This step can be carried out in a workshop in an environment suitable for precision work.

[0070] Then, in a second step, the subassembly 22 is mounted on the main body 4 as described hereinafter, i.e. directly in one operation, said step can be carried out at the location where the atomizer 2 is used, for example in a paint booth.

[0071] This assembly is performed by axial translation of the subassembly 22 parallel to the longitudinal axis A2. This axial translation is represented by the arrow T in Figures 1 and 3A-6B. No further movement of the air delivery skirt 6 and thus of the subassembly 22 is necessary to mount the air delivery skirt 6, and thus of the subassembly 22, on the main body 4.

[0072] Thereby, the mounting of the subassembly 22 on the main body 4 is effected only by relative translational movements between said elements of the atomizer 2 .

[0073] 3A and 3B, the subassembly 22 is aligned on the axis A2 and brought closer to the main body 4. In said step, the rear end 644 of the sleeve 64 is engaged in the central housing L2 without coming into contact with any component of the magneto-pneumatic system 100.

[0074] Continuing the mounting of the subassembly 22 onto the main body 4 brings the sleeve 64 to the substep shown in Figures 4A and 4B where the rear end 644 of the sleeve 64 abuts the permanent magnet 112 by means of the edge 642 of the rear end 644, while the edge 647a abuts the surface S'110, thereby preventing plastic deformation of the end 644 at the end of the stroke.

[0075] In said substep, a closed magnetic flux FM is established through the rear end 644 of the sleeve 64, the parts 110a and 110b of the support 110 and the magnet 112, which has the effect of joining the air-delivery skirt 6 to the support 110 by means of an axial magnetic attraction. This support 110 is held in place in the central housing L2, since the movement between the cap 102 and the cup 104 is restricted. This fixes the entire subassembly 22 relative to the support 110. The axial magnetic attraction between the parts 12 and 64 is parallel to the longitudinal axis A2, preferably centered on this axis, and results in the latching of the air-delivery skirt 6 and thus the subassembly 22 to the main body. This force therefore serves to latch these parts together.

[0076] The permanent magnets 112 are selected to apply a magnetic latching force on the sleeve 64 of sufficient strength to hold the subassembly 22 in place on the main body 4, even when the main body 4 is moved, such as when the subassembly 22 is mounted on the wrist of a multi-axis robot arm or on a reciprocator, thereby subjecting the subassembly 22 to accelerations that may be in the direction of withdrawal of the sleeve 64 relative to the central housing L2.

[0077] In practice, the magnetic latching force applied by the permanent magnet on the sleeve has a strength I1 between 10 and 20 daN, preferably around 15 daN, which allows an effective latching of the air supply skirt 6 and thus of the subassembly 22 to the main body 4. On the other hand, if the strength I1 of this magnetic latching force is of a relatively moderate value, this limits the risk of injury due to pinching the operator when he provides the subassembly 22 and engages the sleeve 64 in the central housing L2.

[0078] 4A, 4B, the subassembly 22 is latched onto the main body 4 by this magnetic force, but the bottom 628a of the concave housing 628 remains spaced apart from the front face 428 of the outer part 42 by a non-zero axial distance D8, which axial distance D8 is measured parallel to the longitudinal axis A2. In particular, in said substep, the seal 20 is not compressed and the sealing between the air circuits formed by the conduits 422 and 622 and the grooves 628c and 628d is not ensured against the outside.

[0079] In the steps and sub-steps shown in Figures 1, 3A, 3B, 4A and 4B, the spring 114 applies a moving force to the support 110 in a direction away from the cup 104. This force has the effect of engaging the stopper 110d in the various volumes V106 until the stopper 110d abuts the ball 108 and thus the ball 108 abuts the cam surface S106 of the piston 106, which has the effect of pushing the piston 106 back towards the bottom 102f of the volume V102. At this time, the variable volume chamber C100 has a minimum volume, which can be seen specifically in the insert B) of Figure 3B.

[0080] In such a position, each ball 108 abuts against the chamfered edge 102e of the cap 102, thereby holding each ball 108 in place within the corresponding volume V106 without protruding radially from the wall 102b along the radial and centripetal directions relative to the longitudinal axis A100. Under such circumstances, the balls 108 do not impede the sliding of the sleeve 64 within the central housing L2 during the sequence of steps shown in Figures 1, 3A, 3B, 4A, and 4B in particular. More specifically, in the sub-steps shown in Figures 4A and 4B, the balls 108 are not engaged within the outer peripheral groove 646.

[0081] Starting with the substeps of Figures 4A and 4B, the passage 102d is supplied with compressed air, as indicated by arrow A in Figures 4A-6B. This has the effect of pressurizing the variable volume chamber C100 and expanding or expanding it towards the cup 104, as can be seen from a comparison of Figures 4A, 4B and 5A, 5B. This axial expansion of the chamber C100 results from the axial movement of the piston 106 parallel to the longitudinal axis A2 towards the cup 104, as indicated by arrow D in Figures 5B and 6B, which movement is due to the difference between the pressure inside the variable volume chamber C100 and the external atmospheric pressure.

[0082] Movement D of the piston 106 has the effect of moving the individual balls 108 towards the cup 104 and thus towards the bottom of the central housing L2, where they are offset relative to the chamfered edge 102e of the wall 102b so that this edge does not impede the centripetal radial movement of the balls 108 through the opening O106. However, because the cam surface S106 of each volume V106 is inclined, movement of the piston 106 towards the cup 104 has the effect of applying a centripetal force on the individual balls 108 about the longitudinal axis A2, indicated by arrow F in FIG. 5B and directed towards the outer peripheral groove 646. This allows the supply of air to the chamber C100 to clamp the individual balls 108 around the sleeve 64 and engage it, i.e., to at least partially penetrate into the outer peripheral groove 646. The ball 108 thus forms a member for engaging the piston 106 in the external relief of the sleeve 64 defined by the outer peripheral groove 646 .

[0083] During the sequence of sub-steps shown in Figures 4A, 4B and 5A, 5B, the ball 108 presses the support 110 towards the cup 104 against the elastic force applied by the spring 114. This has the effect of axially separating the spring 114 and the end 644 of the sleeve 64. In other words, in the sub-steps shown in Figures 5A, 5B, the rear edge 642 of the sleeve 64 does not bear against the magnet 112, and the edge 647a does not bear against the surface S'110. This does not matter, because the ball 108 engaged in the outer peripheral groove 646 now effectively holds the sleeve 64 in the central housing L2.

[0084] At the end of the sub-step of FIGS. 5A and 5B, the value of distance D8 is reduced compared to the same value in the sub-step of FIGS. 4A and 4B, but said value remains non-zero.

[0085] With the continued supply of compressed air to the variable volume chamber C100 through the passage 102d, the piston 106 continues to move toward the cup 104 in the direction of arrow D in FIG. 6B against the elastic force applied by the spring 114. During said movement, the ball 108 abuts the rear edge 646a of the outer peripheral groove 646 and transmits to the sleeve 64 the moving force it experiences due to the movement of the piston 106 toward the arrow D. This causes the sleeve 64 to move toward the bottom of the central housing L2 simultaneously and over the same stroke as the piston 106. This is represented in FIG. 6B by the moving direction arrow D'.

[0086] The movement D' of the sleeve 64 inside the central housing L2 has the effect of pressing the bottom 628a of the concave housing 628 firmly against the front face 428 of the outer part 42 of the body 4, which compresses the seal 20 and fluidically isolates the conduits 422 and 622 and the grooves 628c and 628d from the outside. In other words, the pneumatic mechanism 100B applies an axial mechanical clamping force parallel to the longitudinal axis A2 against the sleeve 64 and by means of the ball 108, which presses the bottom 628a of the concave housing 628 of the air supply skirt 6 firmly against the front face 428.

[0087] Thus, the positioning and fixing of the subassembly 22 on the main body 4 is performed in two steps by the magnetic-pneumatic system 100. The pneumatic mechanism 100B is therefore also a mechanism for locking the subassembly 22 on the main body 4.

[0088] Once in position, the bowl 8, which is rigidly mounted to the air supply skirt 6 by the interaction of the first coupling means 82 and the second coupling means 14, is compressed by a magnetic force E1 applied by these coupling means parallel to the axis of rotation A2 and against the rotor 10, until the frictional force between the surfaces 88 and 108 fixes the bowl and rotor for rotation about the axis of rotation A2.

[0089] Here, this force E1 is fully axial with respect to the axis of rotation A2. In a variant of the invention (not shown), the force E1 is partially axial with respect to the axis of rotation, i.e. inclined with respect to the axis of rotation as envisaged in WO2005 / 082542A.

[0090] 6A and 6B, as the magnetic coupling means 82 and 14 cooperate to accurately position the bowl 8 on the air supply skirt 6, thereby ensuring that in said position the bowl is accurately positioned relative to the rotor 10, specifically at the interface between the surfaces 88 and 108. The bowl 8 is then ready to be driven by the rotor 10.

[0091] According to the technique of WO2005 / 082542A1, when the turbine is in operation, i.e. when the rotor 10 is rotating about the axis of rotation A2, an air bearing is formed between the surface 82 and the magnets 14 by injecting an air flow between these parts, which enables the rotor 10 to rotate the bowl 8 about the axis of rotation A2.

[0092] The mechanical latching device 100A comprising elements 110 and 112 serves to hold the subassembly 22 in place on the main body 4 by supplying compressed air to the variable volume chamber C100, thereby effectively clamping the air supply skirt 6 and thus the subassembly 22 in place on the main body 4, and more specifically by compressing the seal 20, before the pneumatic clamping mechanism 100B comprising elements 102, 106, 108, and 110 is used. The cup 104 and spring 114 are accessories of the mechanical latching device 100A and the pneumatic clamping mechanism 100B in the magnetic-pneumatic system 100.

[0093] The mechanical clamping force provided by the pneumatic clamping mechanism 100B has a strength I2 strictly greater than the strength of the magnetic force mentioned above.

[0094] For example, the mechanical force provided by the pneumatic clamping mechanism 100B may have a magnitude between 80-200 daN, preferably between 100-150 daN, or preferably about 120 daN.

[0095] When it is appropriate to disassemble the subassembly 22 from the main body 4, the supply of compressed air to the variable volume chamber C100 is stopped and the passage 102d is vented. The spring 114 then pushes the support 110, ball 108, and piston 106 towards the bottom 102f of the volume V102, reducing the volume of the variable volume chamber C100.

[0096] The ball 108 then abuts against the chamfered edge 102e of the wall 102b, which has the effect of withdrawing the ball from the outer peripheral groove 646 by moving it back towards the interior of the volume V106. In other words, the ball 108 is no longer engaged in the outer peripheral groove 646. The elastic force applied by the spring 114 then tends to return the piston to a position where the ball 108 can be disengaged from the outer peripheral groove 646 of the sleeve 64.

[0097] Pushed back by spring 114, support 110 is driven along with magnet 112 which comes into contact with rear edge 642 of sleeve 64, which has the effect of re-establishing the magnetic latching force between sleeve 64 and magnet 112. Magnetic-pneumatic system 100 then assumes a configuration similar to that of Figures 4A and 4B, seal 20 is no longer compressed, and subassembly 22 remains latched onto main body 4 by the magnetic force resulting from magnetic flux FM, indicated by arrows F. Subassembly 22 is securely held onto main body 4 for the reasons discussed above.

[0098] During a first disassembly step, it is then possible to remove the subassembly 22 by applying an axial force in a direction opposite to that of the arrow T in Figures 1 and 3A-6B.

[0099] In this regard, a disassembly tool (not shown) may be used for this purpose.

[0100] Then, during a second disassembly step, bowl 8 is separated from air supply skirt 6 against the magnetic force between magnet 14 and surface 82. As with the first step of the assembly process, the second step of the disassembly method can be carried out in a workshop in an environment suitable for precision work.

[0101] The structure of the subassembly 22 and magnetic-pneumatic system 100 of the present invention is compatible with robotic placement of the subassembly 22 on the main body 4 and robotic removal of the subassembly 22. Thus, according to one particular embodiment, the present invention allows for the automation of the assembly and disassembly of the air delivery skirt and bowl on and from the main body of the atomizer.

[0102] In one variant, the variable volume chamber C100 of the magneto-pneumatic system 100 can be supplied with a pressurized gas different from air.

[0103] According to one variant of the invention (not shown), the variable volume chamber C100 of the system 100 can be supplied with a liquid, in particular water, to control the movement D of the piston 106. In such a case, the system 100 is a magneto-hydraulic system.

[0104] According to another variant, during the substeps shown in Figures 4A and 4B, the edge 642 of the sleeve 64 abuts against the support 110 rather than against the magnet 112. This makes it possible to generate a closed magnetic flux, such as the closed magnetic flux FM shown in Figure 4B.

[0105] The magneto-pneumatic system 100 can be used automatically, using the magnetic force generated by the permanent magnets 112 and controlling the supply of compressed air into the variable volume chamber C100 or its casing by valves controlled by an electronic control unit (not shown). This allows the automation of the operation of the magneto-pneumatic system 100 during the assembly or disassembly of the subassembly 22, thereby eliminating operator work near the atomizer 2 and reducing the risks of operator work.

[0106] In one variant of the invention (not shown), the O-ring 20 is mounted in a groove formed in the bottom 628a of the recessed housing 628 and / or grooves equivalent to grooves 628c and 628d are provided on the front face 428 of the outer part 42 of the main body 4.

[0107] In the second, third and fourth embodiments of the present invention shown in Figures 7 to 9, elements similar to those in the first embodiment have the same reference numerals. Hereinafter, when a reference numeral is used in the description without being shown in any of Figures 7 to 9, or when it is shown in any of said drawings without being mentioned in the description, this reference numeral refers to the same element as the element having the same reference numeral in the first embodiment.

[0108] In the second, third and fourth embodiments, a magneto-pneumatic or magneto-hydraulic system of the type of system 100 of the first embodiment is not provided.

[0109] In the second embodiment, a permanent magnet 14 is mounted on the bowl 8 while an annular front surface 682 of a collar flange 649 made from a ferromagnetic material is positioned opposite the magnet 14 in the mounted configuration with a subassembly 22 defined similarly to the first embodiment. The magnet 14 and the surface 682 of the collar flange 649 form a first magnetic coupling means and a second magnetic coupling means between the parts 6 and 8.

[0110] The sleeve 64 of the air-delivery skirt 6 is provided with a thread 650 on its radially outer surface 64, while the outer part 42 of the main body 4 is provided with tappings 421 in the housing L2 that match the thread 650, so that the subassembly 22, once formed, can be screwed onto the main body 4 by using the thread 650 and the tappings 421 until the rear edge of the sleeve abuts against the bottom 423 of the housing L2 or the bottom 628a of the concave housing 628 abuts against the front face 428 during mounting of the air-delivery skirt 6 and the bowl 8 on the atomizer 2.

[0111] On the other hand, during disassembly, the subassembly 22 is removed by unscrewing.

[0112] In the third embodiment, the permanent magnet 14 is positioned on the collar flange 649 as in the first embodiment. The surface 82 is formed by a ring 83 made of a ferromagnetic material mounted directly on the bowl 8. This bowl 8 does not necessarily have to be made of a ferromagnetic material, for example made of aluminium.

[0113] In this case, the sleeve 64 of the air-delivery skirt 6 is mainly composed of the collar flange 649, but does not include the part that extends into the concave housing 628. The skirt 651 surrounding the concave housing 628 is provided with tappings 653 on its radially inner surface, while the outer part 42 of the main body 4 is provided with threads 421 on its radially outer surface, so that the subassembly 22, once formed, can be screwed onto the main body 4 by using the threads 421 and the tappings 653, until the bottom 628a of the concave housing 628 comes into abutment against the front face 428, during the installation of the air-delivery skirt 6 and the bowl 8 on the atomizer 2.

[0114] On the other hand, during disassembly, the subassembly 22 is removed by unscrewing.

[0115] In the fourth embodiment, the surface 82 of the bowl 8 is a single piece with the remainder of the bowl, and the permanent magnet 14 is positioned on the collar flange 649 as in the first embodiment.

[0116] In this case, a permanent magnet 441 is housed in the bottom of the housing L2 and cooperates with the rear edge 642 of the sleeve 64 to apply a magnetic clamping force to the main body 4 for the subassembly 22 defined in the same manner as in the first embodiment.

[0117] In a variant of the fourth embodiment, the magnet 441 is mounted on the rear of the sleeve 64 and can cooperate with a rotor made at least partly from a ferromagnetic material in this case.

[0118] In the second, third and fourth embodiments, the atomizer 2 is assembled in two stages, similar to the first embodiment. In a first assembly step, the air delivery skirt 6 and the bowl 8 are assembled and held together by the magnetic force between the magnet 14 and the surface 82 or 682 to form the subassembly 22. In a second assembly step, the subassembly 22 is mounted directly on the main body 4 in one operation. During disassembly, in the first step, the subassembly 22 is separated from the main body in one operation. Then, in a second disassembly step, the air delivery skirt 6 and the bowl 8 are separated from each other against the magnetic force between the magnet 14 and the surface 82 or 682.

[0119] In one variant, and in any embodiment, the atomizer 2 is an externally charged electrostatic atomizer, comprising a high voltage unit and a charged electrode (not shown) configured to bring the coating product atomized by the atomizer 2 to a given potential.

[0120] According to another variant applicable to all embodiments, the atomizer is not an electrostatic atomizer.

[0121] In one variant, instead of a single annular permanent magnet 14, it is possible to use a number of permanent magnets distributed around the axis of rotation as magnetic coupling means.

[0122] In one variant, the surface 108 is not created directly on the rotor 10, but on another rotating member, for example a hollow shaft driven by the rotor.

[0123] In the above, the invention is explained within the framework of its use for spraying liquid coating products, but the invention also applies to the spraying of powder coating products.

[0124] As far as it is technically feasible, the above-described embodiments and variants can be combined. [Explanation of symbols]

[0125] 2. Atomizer 4 Main body 6 Air supply skirt 8. Atomizer Bowl 10 Rotor, turbine rotor 12 parts 14 Annular permanent magnet, second magnetic coupling means 16 Coating Product Injector 18 Cover 20 O-ring, seal 22 Subassembly 42 External parts, outer parts 44 Internal parts, inner parts 46 Base 48 Screw 62 Skirt body 64 Sleeve, internal radial collar flange, radial outer surface 82 Annular Surface, First Magnetic Coupling Means 83 Ring 84 Center Bore 86 Edge 88 Male truncated cone surface 100 Magnetic-Pneumatic System 100A Magnetic Locking Device, Mechanical Locking Device 100B Pneumatic mechanism, pneumatic clamp fixing mechanism, pneumatic tightening mechanism 102 Cap 102a Tab 102b Radial inner wall 102c Radial outer wall 102d aisle 102e Beveled Edge 102f bottom 103 Center line 104 Cups 106 Annular Piston 106 Piston 106a Groove 106b Groove 107a Seal rings, O-rings, seal segments 107b Seal rings, O-rings, seal segments 108 Ball, female frustoconical surface 110 Support 110a solid body 110b profile 110c pin 110d Stopper 112 Annular permanent magnet 114 Leaf spring 162 Downstream end 421 Thread, tapping 422 Conduits, Channels 423 Bottom 424 Exit 426 Circular Groove 428 Front side 441 Permanent Magnets 442 Conduits, Channels 446 Conduit 622 Conduits, Channels 624 Exit orifice 626 Circular front surface 628 Concave Housing 628a bottom 628c Groove 628d Groove 641 Front end 642 Rear Edge 644 Rear end 646 Outer peripheral groove 646a Rear Edge 647a Edge 649 Internal radial collar flange 650 groove, thread 651 Skirt 653 Tapping 682 Annular Front Surface A100 Longitudinal axis A2 Longitudinal axis, rotation axis C100 Variable Volume Sealed Chamber D8 Axial distance E1 Magnetic force I1 strength I2 strength L2 Center Housing O106 Opening O6 center opening S106 Inner peripheral surface, cam surface S110 First frustoconical inner surface S'110 Second frustoconical inner surface V102 Annular volume, housing V106 Volume section

Claims

1. A rotary atomizer for a coating product (2), comprising a main body (4) and a bowl (8) rotated by a rotating member (10) about an axis of rotation (A2) defined by said main body, said bowl comprising first magnetic coupling means (82; 14) tending to cooperate with matching second magnetic coupling means (14; 682) fixed with respect to a non-rotating part (6) of the atomizer for the coating product (2), said first coupling means and said second coupling means tending to apply a force (E1) at least partially axial with respect to said axis of rotation (A2) of the bowl (8), said force inducing a rotational coupling of the bowl (8) with respect to the rotating member, characterised in that the second magnetic coupling means (14; 682) are supported by an air supply skirt (6) mounted directly on the main body (4), Rotary atomizer for coating products (2).

2. 2. An atomizer according to claim 1, characterized in that the second magnetic coupling means (14; 682) is mounted on or formed by an internal collar flange (649) of the air supply skirt (6) and bears against a front face (428) of the main body (4).

3. 2. An atomizer according to claim 1, characterized in that the first magnetic coupling means (82) are formed by a ferromagnetic part (82; 83) of the bowl and the second magnetic coupling means are formed by at least one permanent magnet (14).

4. 2. The atomizer according to claim 1, characterized in that the first magnetic coupling means are formed by at least one permanent magnet (14) and the second magnetic coupling means are formed by a ferromagnetic portion (682) of the air supply skirt (6).

5. The atomizer comprises a magneto-pneumatic or magneto-hydraulic system (100), the magneto-pneumatic or magneto-hydraulic system comprising: a magnetic device (100A) for hooking said air supply skirt (6) onto said main body (4); a pneumatic or hydraulic mechanism (100B) for locking and clamping the air supply skirt onto the main body; 5. An atomizer according to claim 1, characterized in that it comprises:

6. 6. The atomizer for a coating product according to claim 5, characterized in that the magnetic latching device (100A) is configured to apply an axial magnetic force with a first intensity (I1) parallel to the longitudinal axis (A2) of the atomizer between the air supply skirt (6) and the main body (4), and the pneumatic or hydraulic clamping mechanism (100B) is configured to apply an axial mechanical force with a second intensity (I2) parallel to the longitudinal axis of the atomizer between the air supply skirt (6) and the main body, the second intensity being strictly higher than the first intensity.

7. 7. The atomizer for a coating product according to claim 6, characterized in that the atomizer comprises a seal (20) arranged between the air supply skirt (6) and the main body (4), and the seal, compressed by the mechanical force applied by the pneumatic or hydraulic clamping mechanism (100B), isolates conduits (422, 622) for the circulation of shaping air provided in the main body (4) and in the body (62) of the air supply skirt (6) from the outside of the atomizer (2).

8. 5. An atomizer for a coating product according to any one of claims 1 to 4, characterized in that the air supply skirt (6) is provided with reliefs (650, 653) for screwing into matching reliefs (421, 423) formed on the main body (4).

9. 5. An atomizer for a coating product according to claim 1, wherein the air supply skirt (6) is clamped relative to the main body (44) by a magnetic force applied between a part (441) of the main body (44) and a part (642) of the air supply skirt.

10. A method for assembling and / or disassembling an atomizer for a coating product according to any one of claims 1 to 9, comprising the steps of: When assembling the atomizer, in a first assembly step, the air supply skirt (6) and the bowl (8) are assembled and held together by magnetic forces between the first magnetic coupling means (14, 82) and the second magnetic coupling means (14, 682); in a second assembly step, the subassembly (22) formed by the air supply skirt (6) and the bowl (8) is mounted directly onto the main body (4) in one operation; When disassembling the atomizer, In a first disassembly step, the subassembly (22) formed by the air supply skirt (6) and the bowl (8) is separated from the main body in one operation; In a second disassembly step, the air supply skirt (6) and the bowl (8) are separated from each other against the magnetic force between the first magnetic coupling means (14, 82) and the second magnetic coupling means (14, 682).

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