Spraying member and rotary coating machine for coating products comprising such spraying member

Abstract

The invention relates to a spraying component and a coating product rotary spraying machine comprising the spraying component. The invention relates to a spraying member (30) for a rotary coating machine (2) for coating products, which carries at least one weight (40) for mechanical locking on a drive shaft (16) of the rotary coating machine. The weight is movable radially with respect to a central axis (A30) of the bowl and in a centrifugal direction with respect to said central axis between an unlocked position, in which the weight does not block the mounting of the spray member (30) on the drive shaft (16) or does not block the dismounting of the spray member with respect to the drive shaft, and a locked position, in which the weight does not block the mounting of the spray member (30) on the drive shaft (16) or does not block the dismounting of the spray member with respect to the drive shaft. The weight blocks detachment of the bowl relative to the drive shaft.

Description

Technical Field

[0001] The present invention relates to a spraying component for a rotary spraying machine for a paint product, and a rotary spraying machine for a paint product comprising the spraying component. Background Art

[0002] In the field of spraying paint products, a spray bowl is known, for example from document WO 2005 / 082542 A, which is equipped with a first magnetic connection device that can cooperate with a complementary second magnetic connection device fixed to a non-rotating part of the spray machine. The first and second magnetic connection devices exert an axial force relative to the axis of rotation of the spray bowl, thereby causing the spray bowl and the corresponding drive member to be connected in rotation.

[0003] Overall, the device is satisfactory.

[0004] However, one problem with this device is that the magnetic force between the first and second magnetic coupling means must be strong to ensure that the spray bowl remains in place on the spray machine, even though the spray machine may be subject to significant accelerations when mounted on the end of a multi-axis robot arm. This problem becomes more significant when the mass of the spray bowl is large.

[0005] The strength of the magnetic force between the first and second magnetic coupling means makes it difficult to remove the spray bowl during maintenance operations. In addition, the high magnetic force may be dangerous if an operator's fingers are caught when installing the spray bowl on the spray machine.

[0006] Similar problems also occur for spraying components of the disc type, in other words, such spraying components have an edge, the diameter of which is usually between 120 mm and 500 mm. These problems are aggravated by the relatively large mass of these discs.

[0007] Similar problems also occur for spray components which are mounted on a rotating shaft by means of a connection with non-magnetic connecting means, in particular by screwing, clamping or quarter-turn locking.

[0008] On the other hand, it is known from documents DE 10 2017 212 480 A1, DE 10 2021 127 163 A1 and DE 10 2017 102 965 A1 to mount locking members on the drive shaft of the spraying member. These locking members mounted on the drive shaft tend to wear as they cooperate with several spray bowls in succession. They also make balancing the drive shaft relatively complicated. Finally, if one of these locking members fails, it is necessary to disassemble the drive shaft, which constitutes a relatively complicated and time-consuming operation. Summary of the invention

[0009] It is precisely to address these shortcomings that the present invention more particularly aims to remedy them by proposing a new type of spraying component, which can be bowl-shaped, disc-shaped or other types, and its installation on the rotary spraying machine for coating products will become more reliable without necessarily requiring the use of a connecting device that causes a strong connecting force.

[0010] To this end, the object of the present invention is to provide a spraying member for a rotary spraying machine for coating products, characterized in that the spraying member carries at least one mechanical locking weight for mechanical locking on the drive shaft of the rotary spraying machine, the weight being movable radially relative to the central axis of the spray bowl and in a centrifugal direction relative to said central axis between the following positions:

[0011] an unlocked position, in which the weight does not hinder the installation of the painting member on the drive shaft or the removal of the painting member relative to the drive shaft; and

[0012] - a locked position, in which the weight blocks removal of the spray bowl relative to the drive shaft.

[0013] Thanks to the invention, the weight allows the use of the centrifugal force inherent in the rotational movement of the spraying member about its axis of rotation to lock the spraying member to the drive shaft. When the spray bowl rotates about its axis of rotation, the movement of the or each weight from its unlocked position to its locked position occurs automatically. Furthermore, by providing the weight on the spraying member, the drive shaft can be free of moving parts, which helps balance the drive shaft and prolongs its service life relative to a situation where the drive shaft would carry the locking member.

[0014] In the scope of the present invention, the spraying member for the rotary spraying machine for coating products can be a spray bowl, a spray disc or any other member intended to be driven to rotate to spray liquid or powder coating products. Such a spraying member can also be called a bell or a cup.

[0015] Taking into account the locking function obtained with the weight, the magnetic or mechanical connection force between the spray bowl and the drive shaft can be reduced relative to prior art devices.

[0016] Furthermore, the reduction in magnetic forces makes it easier to remove spray components during maintenance operations, reducing the risk of pinching the operator's fingers.

[0017] In the specific case of a spray disc, fixing the spray disc to the drive shaft allows the use of a conventional drive turbine, which is the same type as that used for the spray bowl, which typically has a diameter between 10 mm and 100 mm.

[0018] According to an advantageous but non-mandatory aspect of the invention, such a spraying member may comprise one or more of the following features, taken in any technically permissible combination:

[0019] The spraying member is provided with first magnetic connection means configured to cooperate with complementary second magnetic connection means to exert an at least partially axial force relative to the central axis of the spray bowl.

[0020] The spraying member comprises a plurality of weights distributed around a central axis, preferably in a regular pattern.

[0021] - the spraying member comprises a sleeve, and each weight is housed in a seat groove formed in the sleeve, the seat groove opening onto the outer radial surface of the sleeve; and,

[0022] • the weight is fully received in the seat in its unlocked position; and

[0023] • The weight protrudes from the seat beyond the outer radial surface of the sleeve in its locked position.

[0024] The housing opens into the outer radial surface of the sleeve through a hole, said hole being dimensioned so as to prevent the weight from escaping from the housing through said hole.

[0025] - Each weight comprises a section for axially abutting against the drive shaft, and the seat comprises a seat portion arranged on the outer radial surface of the sleeve, preferably the seat portion extends on both sides of the other seat portion in a radial direction orthogonal to the central axis of the spray bowl, so that the guide heel of the weight engages in the other seat portion.

[0026] The painting member comprises a sleeve and each weight is formed by a component integral with the sleeve and movable from the locked position towards the unlocked position under inertia by elastic deformation of a portion of the sleeve when the painting member is driven in rotation about its central axis.

[0027] The spraying member comprises an elastic return element for elastically returning the weight toward the unlocking position.

[0028] The elastic return element is an elastically deformable ring which surrounds the sleeve of the spraying member at the weight along the central axis of the spray bowl.

[0029] - An elastically deformable ring bears against the outer radial surface of each segment.

[0030] According to a second aspect, the present invention also relates to a rotary spray machine for paint products, which includes a spraying component, a drive shaft for driving the spraying component to rotate around a rotation axis, and a second magnetic connection device configured to cooperate with a first magnetic connection device of the spraying component, characterized in that the spraying component is a spraying component as described above, and due to the rotation of the spraying component driven by the drive shaft, each weight is brought to its locking position.

[0031] Advantageously, the drive shaft defines a bearing projection against which the or each weight of the spraying member bears in the locked position, preferably the bearing projection being an internal shoulder of the drive shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The invention will become more apparent from the following description given purely as a non-limiting example, with reference to the accompanying drawings, in which:

[0033] - Figure 1 is a partial axial principle cross-sectional view of a spraying machine according to the present invention, and shows a spray bowl according to the present invention being installed in the spraying machine from an exterior view;

[0034] - Figure 2 yes Figure 1 Partial axial principle cross-section diagram of the spray machine and spray bowl;

[0035] - Figure 3 The sprayer and the spray bowl according to the second embodiment of the present invention are in a first use configuration and Figure 2 The view corresponding to detail III in FIG.

[0036] - Figure 4 is in Figure 3 cross-sectional and perspective views of a portion of the spray bowl of the second embodiment in configuration;

[0037] - Figure 5 is similar to Figure 3 , but with the sprayer and spray bowl in a second operating configuration;

[0038] - Figure 6 In the plurality of sub-figures A), B), C) and D) there are shown axial cross-sections and enlarged details, side views, perspective cross-sections and partial views of a spray disc according to a third embodiment of the invention in a first configuration of use; and

[0039] - Figure 7 The sub-figures A), B), C) and D) show the same spray disc in a second configuration of use. DETAILED DESCRIPTION

[0040] Figure 1 and Figure 2 The rotary sprayer 2 shown in FIG. 1 extends along a longitudinal axis A2 and comprises a body 4 formed by a main portion 42 and a plate 44 for distributing air towards an air supply skirt 6 onto a surface 66 of the skirt 6 into which channels 62 arranged in the air supply skirt 6 open. The front surface 66 of the air supply skirt 6 is also the front surface of the sprayer 2.

[0041] For example, a coating product is a liquid paint, primer or clearcoat that is intended to be sprayed onto the body or components of a motor vehicle.

[0042] The sprayer 2 is of an internally charged electrostatic type, and includes a not-shown high-voltage unit configured to raise the paint product sprayed by the sprayer 2 to a given potential.

[0043] The front side of the sprayer component or the sprayer 2 is defined as the side facing the workpiece to be sprayed when the sprayer 2 is in use, and the rear side is defined as the side facing the opposite direction to the front side. Figure 1 and Figure 2 In the embodiment, the front part of the sprayer 2 faces upward and the rear part faces downward.

[0044] The pins 46 allow the elements 42 , 44 and 6 to be fixed and oriented relative to each other.

[0045] The spraying machine 2 also comprises an air turbine 8 which itself comprises a stator 10 and a rotor 12 carrying blades 122 which are subjected to the air flow and drive the rotor 12 in rotation about the longitudinal axis A2.

[0046] The body 4 and the stator 10 are fixed together by screws 13 passing through the elements 44 , 42 and 10 .

[0047] The rotating shaft 16 is fixed to the rotor 12 and rotates together with the rotor 12 about a longitudinal axis A2 , which forms a rotation axis of the rotor 12 and the rotating shaft 16 .

[0048] The rotation axis 16 is provided with a frustoconical surface 162 which is centered on the longitudinal axis A2 and diverges toward the front.

[0049] The rotating shaft 162 is hollow and defines a central bore 164 in which the paint product injector 18 is arranged, supported by a plate 20 on which the turbine 8 and the body 4 of the sprayer 2 are mounted.

[0050] When the spraying machine 2 is in use, the stator 10 does not rotate about the axis A2 and is provided with a support 102 on which the annular permanent magnet 22 is mounted, centered on the longitudinal axis A2.

[0051] The central bore 164 of the rotating shaft 16 comprises a first front portion 164A radially defined by a frustoconical surface 162 , and a second rear portion 164B defined by a cylindrical surface 166 also centered on the axis A2 .

[0052] The smallest diameter of the frustoconical surface 166 is smaller than the diameter of the cylindrical surface 166. Thus, a rearwardly facing shoulder 168 is defined in the bore 164 at the junction between the front portion 164A and the rear portion 164B thereof.

[0053] A spray bowl 30 according to the invention is provided for mounting on a spraying machine 2. The spray bowl 30 is centred on a centre axis A30 which, in the configuration in which the spray bowl 30 is mounted on the spraying machine 2, coincides with the longitudinal axis of rotation A2.

[0054] The spray bowl 30 includes a front portion 32 defining a surface 322 for dispensing a liquid coating product to a spraying edge 324 forming a front end of the spray bowl 30. The spray bowl 30 also includes a sleeve 34 for engagement in the central bore 164 of the rotating shaft 16. The outer peripheral surface 342 of the sleeve 34 is configured to abut against the frustoconical surface 162 of the rotating shaft 16, thereby ensuring that the spray bowl 30 and the rotating shaft 16 are rotationally fixed about the coinciding axes A2 and A3.

[0055] The spray bowl 30 is provided with a flow deflector 36 which is screwed into the sleeve 34 and allows the flow of liquid coating product leaving the syringe 18 to be directed towards the dispensing surface 322 .

[0056] The spray bowl 30 is also provided with a ring 38 made of ferromagnetic material, which is intended to interact with the magnet 22 .

[0057] For example, the ring 38 may be made of steel, while the integral front portion 32 and sleeve 34 are made of aluminum.

[0058] In an alternative embodiment of the invention that is not shown, the front portion 32 and / or the sleeve 34 are made of ferromagnetic material, the portion corresponding to the ring 38 being integral with one or the other of these elements.

[0059] The ring 38 defines an annular surface 382 perpendicular to the central axis A30 , which is arranged facing the permanent magnet 22 when the spray bowl 30 is in the configuration mounted on the spray machine 2 .

[0060] In this configuration, the magnetic flux from the permanent magnet 22 is closed in the ring of ferromagnetic material 38, thereby having the effect of applying a connecting force E1 generally parallel to the coincident axes A2 and A30, which has the effect of pressing the outer peripheral surface 342 firmly against the frustoconical surface 162, thereby rotationally fixing the spray bowl 30 and the rotating shaft 16.

[0061] During operation of the sprayer 2, since the permanent magnet 22 is fixed relative to the body 4 while the spray bowl 30 must be able to rotate, an axial play must be created between the elements 22 and 38, obtained by injecting an air flow between the rear face 163 of the rotating shaft 16 and the front face 203 of the plate 20, which has the effect of creating an air bearing between the parts 16 and 20. For clarity of the drawings, Figure 2 The air bearing is not shown in Figure 2 , surface 382 is shown bearing on front surface 222 of magnet 22.

[0062] In summary, the ring 38 forms a first magnetic connection means and the permanent magnet 22 forms a second magnetic connection means, allowing the application of a magnetic force E1 which is axial and causes the spray bowl 30 to be connected in rotation with the rotating shaft 16, while an air flow, not shown, allows the creation of an air bearing between the rotating shaft and the fixed part of the sprayer 2, which has the effect of pushing the rotating shaft 16 and the spray bowl 30 carried by it forward. As a result, an axial gap is created between the surfaces 222 and 382, ​​allowing the spray bowl 30 to rotate about the axis of rotation A2.

[0063] Here, force E1 is purely axial relative to the rotation axis A2. In an alternative of the invention not shown, force E1 is partially axial relative to the rotation axis, in other words it is oblique relative to the rotation axis, as envisaged in document WO 2005 / 082542 A.

[0064] The sleeve 34 is provided with six grooves 344, each of which is opened to the outer peripheral surface 342 through a first hole 344A.

[0065] A weight 40 is arranged in each seat groove 344. Figure 1 and Figure 2 In the example shown in FIG. 4 , the weight 40 is a ball with a diameter indicated as Φ40.

[0066] Each first hole 344A is circular, and its diameter is denoted by Φ344.

[0067] The diameter Φ344 is slightly smaller than the diameter Φ40, for example 10% smaller, so that there is no risk of the ball 40 being ejected from the seat groove 344 through the first hole 344A, even under the action of centrifugal force when the rotating shaft 16 drives the spray bowl to rotate around the rotation axis A2.

[0068] In the case where the weight 40 alternatively has a non-circular shape, the geometry of the seat groove 344 and the hole 344A is also adjusted. In all cases, the size of the hole 344A can prevent the weight 40 from escaping the seat groove 344 through the hole.

[0069] On the other hand, each seat groove 344 opens to the central channel 346 of the sleeve 34 through a second hole 344B opposite to the first hole 344A thereof. When the deflector 36 is screwed into the sleeve 34, the deflector 36 partially closes each second hole 344B so that the weight 40 cannot leave its seat groove 344 and fully engage in the central channel 346.

[0070] At rest, in other words, when the turbine 8 is not running, the spray bowl 30 does not rotate about the axis of rotation A2, and the weights 40 can be in any position between the holes 344A and 344B in the housings 344. In particular, they can be fully engaged in these housings 344, such as Figure 2 As shown on the left, in this case they neither hinder the placement of the spray bowl 30 on the rotation axis 16 nor its removal therefrom.

[0071] During operation of the sprayer 2, when the spray bowl is driven to rotate about the axis of rotation A2 at a speed of several thousand revolutions per minute, the centrifugal force exerted on the weights 40 has the effect of moving these weights to the position in the spray bowl. Figure 2 The effect of the configuration shown on the right side is that each weight protrudes relative to the outer peripheral surface 342 through the first hole 344A of the corresponding seat groove 344.

[0072] exist Figure 1 and Figure 2 In the embodiment of FIG. 5 , each seat groove 344 extends in a direction radial to the central axis A30 and perpendicular to the central axis. The weight moves in this direction.

[0073] In an alternative embodiment of the present invention, which is not shown, the seat groove extends in a direction inclined toward the front of the spray bowl 3, in which direction the weight 40 moves under the action of the centrifugal force. Advantageously, the angle of inclination between the longitudinal direction of the seat groove 344 and the plane perpendicular to the central axis A30 is between 0 and 45°, preferably between 0 and 30°.

[0074] By protruding in this manner relative to the outer peripheral surface 342 , each weight 40 will face the shoulder 168 , so that the weight blocks the spray bowl 30 from being pulled out relative to the rotation axis 16 in a direction opposite to the direction of the force E1 .

[0075] Therefore, once the rotary sprayer 2 drives the spray bowl 30 to rotate about its rotation axis A2, the weight constituted by the ball 40 fixes the spray bowl 30 to the rotation shaft 16. Therefore, when the spray bowl 30 is driven to rotate about the rotation axis A2 by the rotation shaft 16, the mechanical locking force generated by the interaction between the ball 40 and the shoulder 168 is added to the magnetic force E1 between the first and second magnetic connection devices 38 and 22. Therefore, the strength of the magnetic force E1 can be reduced relative to the strength of the same type of magnetic force in the prior art device.

[0076] Under these conditions, the operation of the spray machine 2 is reliable and the installation of the spray bowl 30 on the rotating shaft 16 is durable even if the magnet 22 generates a relatively low strength magnetic force on the ferromagnetic ring 38. Therefore, the use of the weight 40 can reduce the size, mass and cost of the permanent magnet 22, as well as reduce the air flow required to create an air bearing between the surfaces 222 and 382.

[0077] When the spraying machine 2 stops, the centrifugal force is no longer applied to the weight 40, and the weight 40 can be restored to the state as shown in FIG. Figure 2The position shown on the left is a position in which the weight does not hinder the spray bowl 30 from being pulled out relative to the rotation axis 16 under the action of a force opposing the magnetic force E1.

[0078] Since the magnetic force E1 is not as great as in the prior art due to the smaller magnetic interaction between the elements 22 and 38, the force required to remove the spray bowl 30 is also less.

[0079] Furthermore, since the magnetic force E1 between the elements 22 and 38 is not as strong as in the prior art, there is less risk of injury to the user, in particular of pinching fingers, when mounting the spray bowl 30 to the spray machine 2 .

[0080] exist Figure 3 In the second and third embodiments of the present invention shown in the following figures, elements similar to those in the first embodiment have the same reference numerals. Figures 3 to 7 If a component is labeled on one of the figures, or is labeled in one of the figures but not mentioned in the corresponding description, it indicates the same component as the component in the first embodiment.

[0081] Hereinafter, the points in which the second embodiment differs from the first embodiment are mainly described.

[0082] In the second embodiment, the ball 40 of the first embodiment is replaced by weights 140 , each of which includes a heel 142 and an arcuate section 144 .

[0083] Each heel 142 is oblong, with its longest dimension parallel to the central axis A30 when the weight 40 is in the configuration mounted on the spray bowl 30. In the configuration in which the weight 40 is mounted on the spray bowl 30, each segment 144 extends around the axis A30 over an angular extent of approximately 120°.

[0084] exist Figures 3 to 5 In the example shown, the spray bowl 30 is equipped with three weights, so that the angular amplitude of the section 144 amounts to 120°.

[0085] Alternatively, the number of weights 140 is different, for example equal to one, two, four or six, in which case the angular amplitude of the segment 144 is adjusted, for example equal to 180°, 90° or 60°.

[0086] Preferably, the number of weights 40 is strictly greater than 1 and they are distributed around the central axis A30 .

[0087] In this case, the weights are advantageously evenly distributed around the central axis A30 , which allows balancing the locking forces of the spray bowl 30 on the axis of rotation, the locking forces being obtained with these weights and as will be explained below.

[0088] Each weight 140 extends in a seat groove 344 which includes a first central portion 344C that passes directly through the sleeve 34 and is used to accommodate the heel 142 and a second peripheral portion 344D in the form of a peripheral groove segment arranged on the outer peripheral surface 342 of the sleeve 344 for accommodating the segment 144.

[0089] In other words, Figures 4 to 5 In the embodiment, the three segments 144 of the three weights 140 equipped with the spray bowl 30 together occupy an outer annular groove 348 of the sleeve 34, and the peripheral groove 348 extends 360° around the central axis A30 and is formed by connecting three second peripheral portions 344D of the three seat grooves 344 configured to accommodate the segments 144.

[0090] The cooperation between the portion 344C and the heel 142 allows each weight 140 to be guided in translation in a radial direction relative to the axis A30 .

[0091] Each segment 144 is provided with a peripheral groove 144A extending over the entire angular extent of the segment. The combination of these peripheral grooves 144A forms an annular groove 146 extending 360° around the central axis A30.

[0092] On the other hand, the O-ring 150 is engaged in the annular groove 146 .

[0093] The O-ring 150 surrounds the sleeve 34 of the spray bowl 30 at the weight 140 and the seat groove 344. It rests against the bottom of the annular groove 146 formed by the coupling of the bottoms of the peripheral grooves 144A of the segments 144, which are the outer radial surfaces of these segments.

[0094] The diameter of the seal 150 is selected so that, by default, it presses the weight 140 toward its deepest position in the seat groove 344, which is Figure 3 and Figure 4 In this position, the inner radial surface of the segment 144 abuts against the bottom of the second peripheral portion 344D of the three seat grooves 344.

[0095] In this position, the weight 140 and the O-ring 150 do not protrude radially beyond the outer peripheral surface 342 of the sleeve 34, so that the weight 140 does not obstruct the installation or removal of the spray bowl 30 on the spray machine 2.

[0096] In this position, each weight 140 is in an unlocked position.

[0097] When the spraying machine 2 is running and drives the spray bowl 30 to rotate around the rotation axis A2, the weight 140 is subjected to the centrifugal force in the seat groove 344 and moves radially relative to the axis A2 to reach Figure 5 , in which the section 144 of the weight protrudes radially relative to the outer peripheral surface 342 of the sleeve 34 and is aligned with the inner shoulder 168 of the rotating shaft 16 in a direction parallel to the axis A2.

[0098] Thus, depending on whether the spray bowl 30 is driven in rotation or not, the section 144 selectively faces the shoulder 168 and, where appropriate, abuts against it. The section 144 is the section that abuts axially against the drive shaft 16 .

[0099] In this configuration, the weight 140 blocks the pulling-out movement of the spray bowl 30 relative to the rotation axis 16 in the direction opposite to the direction of the magnetic force E1 as defined in the first embodiment.

[0100] Once the rotation of the spray bowl 30 stops, the elastic force applied by the O-ring 150 to the weights 140 will restore these weights to their original positions. Figure 3 and Figure 4 Thus, the O-ring 150 ensures that once the rotation of the spray bowl 30 has stopped, the weight returns to its unlocked configuration.

[0101] Furthermore, the seating grooves 344 do not need to have openings on the outer peripheral surface 342 that are smaller than the size of the weight 140 because the seal 150 blocks the weight 140 from completely moving out relative to these seating grooves.

[0102] On the other hand, the shape of the segment 144 also prevents the movement of the weight 144 towards the central hole 346, wherein the segment 144 has a width in an orthoradial direction relative to the central axis A30 that is greater than the orthoradial dimension of the portion 344C.

[0103] In this respect, the fact that the sum of the angular sectors over which the various segments 144 extend is approximately equal to 360° also prevents the weight 144 from engaging in the central bore 346 .

[0104] exist Figure 6 and Figure 7 In the third embodiment shown, the spraying member 30 is a spray disc which also comprises a front portion 32 and a sleeve 34 defining three housings 344, each housing being formed by two portions 344C and 344D.

[0105] The weights 140 are the same as those of the second embodiment, and each weight includes a heel 142 and a segment 144 .

[0106] The seating grooves 344 are the same as those of the second embodiment, and each seating groove includes a first central portion 344C and a second peripheral portion 344D.

[0107] Each segment 144 defines a peripheral groove 144A that forms part of the annular groove 146. Figure 6 and Figure 7 As shown in sub-figure D in FIG. , the O-ring 150 is engaged in the annular groove.

[0108] exist Figure 6 In the rest configuration shown, the weights 140, and in particular their sections 144, do not protrude radially from the housing 344 beyond the peripheral surface 342 so that they do not obstruct the positioning of the spray disc 30 on the axis of rotation of a spray machine similar to the first and second embodiments.

[0109] exist Figure 7 The configuration shown, according to operations similar to those described above with respect to the second embodiment, assumes that the spray disc 30 is rotating until the centrifugal force exerts a force on the weight 140 radially relative to the central axis A30, which force causes the segments 144 to partially leave the seats 344, more specifically, the second portions 344D of these seats, so that these segments block the removal of the spray disc relative to the axis of rotation of the sprayer.

[0110] from Figure 7 As can be seen from the sub-graph D in FIG. 1 , under the action of the centrifugal force, the segments 144 of the weight 140 may no longer be connected, but they are Figure 6 In the unlocked configuration.

[0111] In fact, in the second and third embodiments, the O-ring 50 is made of an elastomer, in particular a FKM type fluororubber, acrylonitrile butadiene rubber, ethylene propylene diene monomer (EPDM) or other rubber.

[0112] As an alternative of the present invention not shown, in the second and third embodiments, the O-ring 50 may be replaced by an elastically deformable rope, rod, square or other cross section, and solid or hollow section.

[0113] According to another alternative solution of the present invention, not shown, an elastic return member similar to the O-ring 150 may be used in the first embodiment.

[0114] According to an alternative solution of the invention, not shown, in the second and third embodiments, the weight 140 does not have the heel 142. In this case, the housing 344 does not have the first central portion 344C, and the weight 140 is not guided in radial translation relative to the central axis A30 by the cooperation of the portions 144 and 344D, thereby accommodating a possible rotation of the segment 144 around the axis A30.

[0115] According to another alternative, no elastic return means for elastically returning the weight 140 to the unlocked configuration is provided. In other words, the O-ring 150 is absent in the second and third embodiments.

[0116] The shape of the weight shown in the figure is not restrictive, and the weight can take other shapes compatible with the weight moving between the unlocked position and the locked position under the centrifugal force generated by the rotation of the spraying member 30. The shape of the seat groove 344 is adapted to the shape of the weights 40 and 140. For example, the weight can take one of the following shapes: parallelepiped, pointed arch or hemispherical.

[0117] According to an alternative of the invention, not shown, each weight is formed by a part integral with the sleeve 34. This integral part can be produced by machining the sleeve or by additive manufacturing, connected to the sleeve by elastically deformable tongues also integral with the sleeve, which connect the weight to the main part of the sleeve and allow the weight to move radially relative to the central axis A30 under the effect of centrifugal force when the spraying member is driven in rotation about its central axis A30.

[0118] The invention has been described above in the context of using the connecting magnetic force E1 to clamp the coating member 30 to the rotating shaft 16 and the locking obtained with the weight allowing the strength of this magnetic force E1 to be limited.

[0119] According to an alternative not shown of the invention, the rotational connection of the spray bowl and the rotating shaft is obtained by tightening. In this case, the locking obtained by the weight allows limiting the tightening torque required to connect the spray bowl and the rotating shaft.

[0120] According to another alternative of the present invention, not shown, the rotational connection of the spray bowl and the rotating shaft is obtained by a quarter-turn locking, in particular with a bayonet. In this case, the locking obtained by the weight allows limiting the torque applied to connect the spray bowl and the rotating shaft.

[0121] According to another alternative of the invention, not shown, the rotational connection of the spray bowl and the rotating shaft is obtained by clamping, in particular according to the technical teaching of document WO 94 / 12286 A. In this case, the locking obtained by the weight allows limiting the rigidity of the clamping member, which helps to position the spray bowl on the rotating shaft.

[0122] In all cases, the locking obtained by the centrifugal weight allows the connection of the spray bowl to the rotating shaft, which is achieved by other magnetic and / or mechanical means, to be made more reliable.

[0123] Alternatively, regardless of the embodiment, the sprayer 2 is of an externally charged electrostatic type, comprising a high voltage unit and a charging electrode (not shown) configured to raise the paint product sprayed by the sprayer 2 to a given potential.

[0124] According to another alternative, applicable to all embodiments, the sprayer 2 is not of the electrostatic type.

[0125] Alternatively, instead of a single annular permanent magnet 22, a plurality of permanent magnets distributed around the axis of rotation may be used as magnetic connection means.

[0126] The invention has been described above in the context of its use in spraying liquid coating products. The invention is also applicable to the spraying of powder coating products.

[0127] As long as technically feasible, any features described above for one embodiment or alternative may be used in other embodiments and alternatives described above.

Claims

1. A spraying component (30) for a rotary spraying machine (2) for coating products, characterized in that: The spraying member carries at least one weight (40; 140) for mechanical locking on the drive shaft (16) of the rotary spraying machine for coating products, the weight being movable radially relative to the central axis (A30) of the spray bowl and in a centrifugal direction relative to said central axis between the following positions: an unlocked position, in which the weight does not hinder the installation of the spraying member (30) on the drive shaft (16) or the removal of the spraying member relative to the drive shaft; and - a locked position, in which the weight blocks removal of the spray bowl relative to the drive shaft.

2. The spraying component according to claim 1, characterized in that: The spraying member is provided with a first magnetic connection device (38) configured to cooperate with a complementary second magnetic connection device (22) to apply an at least partially axial force (E1) relative to a central axis (A30) of the spray bowl.

3. The spraying component according to claim 1, characterized in that: The spraying member includes a plurality of weights (40; 140) distributed around a central axis (A30).

4. The spraying component according to claim 3, characterized in that: The plurality of weights (40; 140) are distributed in a regular pattern around the central axis (A30).

5. The spraying component according to claim 1, characterized in that: The spraying member comprises a sleeve (34); each weight is received in a seat groove (344) formed in the sleeve, the seat groove opening to the outer radial surface (342) of the sleeve; and, - in the unlocked position of the weight, the weight (40; 140) is completely housed in the seat (344); and In the locked position of the weight, the weight (40; 140) protrudes from the seat (344) beyond the outer radial surface (342) of the sleeve (34).

6. The spraying component according to claim 5, characterized in that: The seat groove (344) opens to the outer radial surface (342) of the sleeve through a hole (344A), and the hole has a size (Φ344) that can prevent the weight (40) from escaping from the seat groove through the hole.

7. The spraying component according to claim 5, characterized in that: Each weight (140) includes a section (144) for axially abutting against the drive shaft (16); and the seat groove includes a seat groove portion (344D) arranged on the outer radial surface (342) of the sleeve.

8. The spraying component according to claim 7, characterized in that: The seat groove portion (344D) extends on both sides of the other seat groove portion (344C) in a radial direction orthogonal to the central axis (A30) of the spray bowl, and the heel portion (142) is engaged in the other seat groove portion to guide the weight.

9. The spraying component according to claim 1, characterized in that: The spraying member comprises a sleeve (34); and each weight is formed by a component integral with the sleeve, which can move from a locked position toward an unlocked position under inertia through elastic deformation of a portion of the sleeve when the spraying member is driven to rotate about its central axis.

10. The spraying component according to any one of claims 1 to 9, characterized in that: The spraying component comprises an elastic return element (150) for elastically returning the weight (40; 140) toward an unlocking position.

11. The spraying component according to claim 10, characterized in that: The elastic return element is an elastically deformable ring (150) which surrounds the sleeve (34) of the spraying component (30) at the weight (40; 140) along the central axis (A30) of the spray bowl.

12. The spraying component according to claim 11, characterized in that: - Each weight (140) comprises a section (144) for axially abutting against the drive shaft (16); - the housing comprises a housing portion (344D) arranged on the outer radial surface (342) of the sleeve; and An elastically deformable ring (150) bears against the outer radial surface (144A) of each segment (144).

13. A rotary spraying machine (2) for coating products, comprising a spraying member (30) and a drive shaft (16) for driving the spraying member to rotate around a rotation axis (A2), characterized in that: The spraying member (30) is a spraying member according to any one of the preceding claims; and each weight (40; 140) is brought into its locking position due to the rotation of the spraying member driven by the drive shaft (16).

14. The coating product rotary spraying machine according to claim 13, characterized in that: The drive shaft (16) defines a bearing projection (168) against which each weight (40; 140) of the spraying member rests in the locked position.

15. The coating product rotary spraying machine according to claim 14, characterized in that: The bearing projection is an inner shoulder (168) of the drive shaft (16).

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