FEEDING UNIT AND POWDER COATING SYSTEM WITH SUCH A FEEDING UNIT

Description

[0001] The present invention relates to a unit for supplying a powder coating station with powder coating product.

[0002] The technical field of the invention is that of powder coating stations or installations, in which one or more sprayers project a powder coating product onto objects to be coated. This or these sprayers can be manual or automatic, in which case they are advantageously moved by a robot of the multi-axis or reciprocating type.

[0003] In this type of station, it is known to provide a unit or central unit for supplying the powder coating station, more particularly its sprayer(s), with a powder coating product. Such a unit generally comprises a carcass or casing, installed in the vicinity of a coating booth and which defines an internal volume in which a reservoir of fluidized coating product is arranged. This reservoir of fluidized coating product is supplied by a pump which sucks the powder coating product into a container placed on a support, for example a vibrating table.

[0004] Prior art power supply units are known from US2019 / 314836A1, US7074274B1, US7325750B2 and US 2007 / 235558 A1.

[0005] The powder coating product is often available packaged in a cardboard box or bag weighing around 20 kilograms (kg) or more. During a working day, several full containers of powder must be successively loaded onto the support, in a confined space, close to the fluidized coating product reservoir, in the internal volume of the carcass. When a container has been completely or partially emptied, it must be unloaded from the support and removed from this confined space, to allow the installation of another container, for example in the event of a change in the color of the coating product to be sprayed. Depending on the coating product consumption of the powder coating station, loading / unloading operations of coating product containers onto the support may take place up to ten times during an eight-hour shift.These operations take place in a confined space, which can lead to increased fatigue and musculoskeletal disorders for an operator.

[0006] It is these problems that the invention more specifically intends to remedy by proposing a new supply unit for a powder coating station, the loading of which with powder coating product is facilitated.

[0007] To this end, the invention relates to a unit for supplying a powder coating station with powder coating product, this supply unit comprising a reservoir of fluidized coating product, a support for receiving a container of coating product, a pump for supplying the reservoir of fluidized coating product from the container carried by the support and a carcass which defines an internal volume for receiving the reservoir of fluidized coating product and which is provided with an opening for access to this internal volume. According to the invention, the support is movable in rotation or in circular translation around at least one axis, in both directions, at least between a first loading / unloading position, in which the support protrudes outside the internal volume of the carcass, through the access opening; and a second coating product transfer position, in which the support and a container in place on the support are included in the internal volume of the carcass.

[0008] By virtue of the invention, the rotation or circular translation of the support makes it possible to bring it into its first position, in which it is easily accessible for an operator since it protrudes outside the carcass, which facilitates the loading of the support with the container filled with powder coating product. This avoids the operator having to carry the container of coating product to the inside of the supply unit. This makes it possible to greatly limit fatigue and avoid musculoskeletal disorders for the operator. The same advantages are induced when it is necessary to unload a container from the support, this container being able to be empty or partially filled with powder coating product, in particular in the event of a change of color.In the second position, the support and the container in place on this support are correctly arranged, in the internal volume of the carcass, so that the pump can suck the coating product into the container. As the support and the container are included in the internal volume of the carcass, they do not hinder the passage of operators or transport trolleys near the supply unit, which improves the safety of the powder coating station. The rotation or circular translation implemented for the movement of the support between its two positions has the advantage of being a simple, well-controlled movement, which does not cause any obstruction of the space outside the carcass.

[0009] According to advantageous but not mandatory aspects of the invention, such a power supply unit may incorporate one or more of the following features taken in any technically admissible combination: The axis of rotation is vertical and preferably arranged, in part, in the internal volume of the carcass. The support is equipped with a vibrating table. The support is movable in rotation or in circular translation, from one of its first and second positions, to a third position for purging the fluidized coating product reservoir, and vice versa from the third position to one of its first and second positions. In the third position of the support, the coating product container is arranged under the fluidized coating product reservoir. A rotation angle of the support between its first and second positions is between 100 and 180°, preferably between 120° and 160°, more preferably of the order of 135°. Preferably, a rotation angle of the support, between its first and third positions is between 70 and 110°, preferably between 80° and 100°, more preferably of the order of 90°.The container is equipped with a cover provided with a tube for passing a suction rod for the coating product when the support is in its second position, while this tube is arranged under a drain opening of the fluidized coating product reservoir when the support is in its third position. The support is equipped with at least one handle for driving the support in rotation between its first and second positions, and possibly between these first and second positions and the third position. The support is configured to receive containers of the tray type, in particular a rigid tray for a bag of coating product, or of the cardboard type.

[0010] According to a second aspect, the invention relates to a powder coating station which comprises at least one powder coating product sprayer installed in a coating booth and supplied with coating product by a supply unit as mentioned above.

[0011] Such a powder coating station induces the same advantages as those mentioned above regarding the supply unit, in particular in terms of reduction of musculoskeletal disorders for the operator and safety.

[0012] The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of two embodiments of a supply unit and a powdering station in accordance with its principle, given solely by way of example and with reference to the appended drawings in which: [ Fig.1 ] There figure 1 is a schematic perspective representation of a powdering station and a supply unit according to a first embodiment of the invention; [ Fig.2 ] There figure 2 represents, on two inserts A) and B), the power supply unit in front view and in vertical section according to plane B at the figure 1 , in the configuration of the figure 1 ; [ Fig.3 ] There figure 3 is a view analogous to the figure 2 , when a support of the power unit is in the loading position; [ Fig.4 ] There figure 4 is a view analogous to the figure 2 when the support of the supply unit is in the purge position of a reservoir of fluidized coating product; [ Fig.5 ] There figure 5 is a view analogous to the figure 1 , for an installation and a power supply unit in accordance with a second embodiment of the invention; [ Fig.6 ] There figure 6 is a view analogous to the figure 2 , for the second embodiment; [ Fig.7 ] There figure 6 is a view analogous to the figure 3 , for the second embodiment; and [ Fig.8 ] There figure 8 is a view analogous to the figure 4 , for the second embodiment.

[0013] There figure 1 represents a powder coating station or installation 2 which comprises a coating booth 4 in which objects, not shown, are moved along a conveyor axis A4, by a conveyor, also not shown, whose swings pass through a longitudinal slot 42 made in the ceiling 44 of the booth 4. The booth 4 contains one or more sprayers 6, only one of which is shown, very schematically, at the figure 1 and which is oriented towards the objects moved by the conveyor, inside cabin 4.

[0014] In the example of the figures, the sprayer 6 is an automatic sprayer moved by a multi-axis robot not shown, along the three axes X, Y, Z of an orthogonal reference frame XYZ, the X axis being parallel to the conveying axis A4. Alternatively, the robot is of the reciprocating type or of another type and the movement of the sprayer 6 took place along some or all of the axes X, Y, Z. According to another alternative, the sprayer 6 is a manual sprayer carried by a painter who stands in the booth 4.

[0015] The sprayer 6 can be of the electrostatic or triboelectric type.

[0016] The number of sprayers 6 in cabin 4 is adapted to its volume and the size of the parts to be coated.

[0017] The powder coating station 2 also comprises a supply unit 10 which serves to supply each sprayer 6 with a mixture of air and powder coating product, from a reservoir 102 arranged in the internal volume V104 of a carcass 104 which constitutes the outer casing of the supply unit 10 and which, in the example of the figures, is parallelepipedal and attached to the coating booth 4.

[0018] Unit 10 may also be referred to as the powder coating plant.

[0019] A bracket 103 supports the tank 102 in the internal volume V104, in a fixed position relative to the carcass 104. The tank 102 is thus relatively isolated from the external environment of the powdering station 2 and mechanically protected against shocks.

[0020] The carcass 104 also has the function of limiting the diffusion of powder grains out of the feeding station 10.

[0021] A supply conduit 106 connects the reservoir 102 to each sprayer 6.

[0022] As visible to the figures 2 à 4 , a connection plate 108 is fixed on a bottom wall 110 of the carcass 104 and a first part 106A of the conduit 106 extends between the reservoir 102 and the plate 108, in the internal volume V104, while a second part 106B of this conduit extends between the plate and the sprayer 6, outside the internal volume V104.

[0023] The reservoir 102 is supplied with powder coating product by a pump 112 which also belongs to the supply unit 10 and which is fixed to the outside of a first side wall 114 of the carcass 104. A second conduit 116 connects the outlet 112B of the pump 112 to the reservoir 102 and comprises a first part 116A which extends inside the internal volume V104, between the reservoir 102 and the plate 108, and a second part 116B which extends between the plate 108 and the pump 112, outside the internal volume V104.

[0024] The positioning of the pump 112 shown in the figures is not limiting. Alternatively, the pump 112 can be installed on the inside of the side wall 114, on the bottom 110, in particular on the side of this bottom facing the outside of the carcass 104, opposite the volume V104, on the floor 111, on the ceiling 113 or on the second side wall 115 of the carcass 104.

[0025] A front-rear direction of the power supply unit 10 is defined as a direction parallel to the Y axis and oriented in the same direction as this axis. An opening O104 for access to the volume 104 is defined by the front edges of the floor 111, the ceiling 113 and the side walls 114 and 115, these front edges being those visible at figure 1 and on inserts B) of the figures 2 à 4 .

[0026] The inlet 112A of the pump 112 is supplied with powdered coating product contained in a carton 118 placed on a support 120.

[0027] In the configuration of the figure 1 , the powder coating product can be conveyed to the sprayer 6 in fluidized form. This position is therefore a position for transferring the coating product, from the carton 118 to the reservoir 102, then from the reservoir 102 to the sprayer 6. In this position, the support 120 and the carton 118 are completely included in the internal volume V104 of the carcass 104. In other words, the carton 118 and the support 120 do not protrude from the volume V104, through the opening O104. The carton 118 and the support 120, which do not protrude outside the volume V104, do not risk hindering operators or transport trolleys moving in the vicinity of the powder coating station 2.

[0028] Advantageously, the support 120 is equipped with a vibrating table 121 which makes it possible to shake the cardboard 18 in the configuration of the figures 1 And 2, in order to facilitate the grouping of the coating product in its lower corner. An upper face of the vibrating table 121 is inclined and allows the cardboard 118 to rest with an inclined configuration facilitating the concentration of the coating product in a lower corner of the cardboard 118.

[0029] In the configuration of the power supply unit 10 shown in figures 1 And 2 , a suction rod 122 plunges into the cardboard 118 while being held in place by means of a bracket 124 fixed to the second side wall 115 of the carcass 104.

[0030] A third conduit 126 connects the upper end of the suction pipe 122 to the inlet 112A of the pump 112. A first part of the conduit 126 extends between the suction pipe 122 and a connection plate 128 fixed to the bottom wall 110, in the internal volume V104, while a second part of this conduit extends between the plate 128 and the inlet 112A of the pump 112, outside the internal volume V104.

[0031] A sheath 130 is arranged on the internal face of the wall 115 facing the volume V104 and configured to receive the suction rod 122 when it is not in place on the bracket 124 to plunge into the cardboard 118.

[0032] For clarity of the drawing, the conduits 106, 116 and 126 are shown as directly connecting the parts 6, 102, 112 and 122 of the powdering station 2 to the figure 1 . The different parts of these conduits are visible on the inserts A) of the figures 2 à 4 and are not shown in the inserts B) of these figures.

[0033] The reservoir 102 is equipped with means known per se for fluidizing the coating product coming from the pump 112, so that it can be conveyed easily and with a controlled flow rate to the, or to each, sprayer(s) 6. To do this, the reservoir 102 may comprise a porous plate (not shown) above which the coating product coming from the pump 112 is poured and through which an upwardly directed air flow extends, which has the effect of suspending the coating product in the air.

[0034] In the configuration of the power supply unit 10 shown in figures 1 et 2 , the cardboard 118 in place on the support 120 is arranged on one side of the volume V104, being offset, parallel to the X axis, relative to the reservoir 102 and being located below this reservoir, along the Z axis. In this configuration, the cardboard 118 is correctly positioned with respect to the bracket 124, being located completely inside the volume V104, so that the suction rod 122 can plunge into the interior volume of this cardboard.

[0035] In this configuration, the carton 118 is relatively difficult to access. In particular, if an operator were to install the carton 118 on the support in the configuration of the figures 1 And 2, he would have to contort himself and work partly in a cantilever, unless he himself entered the volume V104, where he would be hindered by the tank 102 and by the brackets 103 and 124 against which he could injure himself. By repeating this operation several times per workstation, the operator would risk tiring prematurely and suffering from musculoskeletal disorders.

[0036] To overcome this difficulty, the support 120 is movable in rotation around an axis Z120, which is vertical and parallel to the Z axis in the example of the figures. A rotation is a simple movement, easy to implement with known means, such as bearings.

[0037] The axis Z120 passes through the floor 111, such that its portion located between the floor 111 and the ceiling 113 is located in the internal volume V104 of the carcass 104. This gives good compactness to the power supply unit 10.

[0038] The support 120 can thus move from the position shown to the figures 1 And 2 to that represented in the figure 3 , in which the support 120 protrudes outside the volume V104, through the opening O104, such that a carton 118 is also arranged at least partly outside the volume V104 while being easily accessible for an operator, to load a carton onto the support 120 or unload a carton from the support 120. This position is therefore a position for loading / unloading the support 120 with containers which, in this embodiment, are cartons 118.

[0039] The passage of the support 120 from its transfer position of the figures 1 And 2 to its loading / unloading position of the figure 3 is reversible. It can take place in both directions.

[0040] To facilitate the work of the operator and the rotation of the support 120 around the axis Z120, the support 120 is equipped with two handles 132 and 134 which extend upwards from the support, in particular up to above a cardboard box placed on the support. Given their geometry, the handles are easily accessible, without the operator having to bend over. They make it possible to exert on the support 120 a driving torque in rotation of this support around the axis Z120, without having to bend over significantly. This torque can be exerted in the direction of the arrow R1 at figure 3 , to move from the loading / unloading position to the transfer position, or in the direction of arrow R2 to the figure 2 , to move from the transfer position to the loading / unloading position.

[0041] The support 120 therefore takes, depending on its orientation around the axis Z120, a first position for loading / unloading the cardboard 118 onto the support 120, which is shown in figure 3 , and a second position for transferring the coating product, which is shown in figures 1 And 2 .

[0042] The operator's work is made easier because access to the support 120 to place the cardboard 118 containing the powder coating product there is facilitated in the loading / unloading position of the figure 3 , whereas the cardboard 118 and the support 120 do not protrude outside the volume 104 in the transfer position of the support 120, which is advantageous in terms of safety and in terms of compactness of the supply unit 10, therefore of the powdering station 2.

[0043] In practice the angle α of rotation of the support 120, in the anti-trigonometric direction in top view shown on the inserts B) of the figures 2 And 3 , between its first and second positions can be between 100 and 180°, preferably between 120° and 160°, more preferably of the order of 135°. Alternatively, the rotation of the support 120 between its first and second positions can be carried out in the trigonometric direction in top view to reach the same point. In this case, the angle of rotation of the support has a value equal to the difference between 360° and the value of the angle in the case of a rotation in the anti-trigonometric direction.

[0044] Advantageously, a third position is provided for the support 120. This third position is shown in figure 4 . In this third position, the carton 118 is located below the reservoir 102, which makes it possible to purge the reservoir by letting the powdered coating product it contains fall by gravity into the carton 118. A purge sleeve valve 105 is provided in the lower part of the reservoir 102 and makes it possible to control the discharge of the residues of coating product present in the reservoir 102, through an opening controlled by the sleeve valve 105, towards the carton 118 in place on the support 120 in its third position.

[0045] In this third purge position of the tank 102, the support 120 protrudes outside the carcass 104, in a less marked manner than in the loading / unloading position of the figure 3 The carton 118 is not actually accessible but this is not important since, in this configuration, it is not a question of loading or unloading the carton 118 onto the support 120 but of recovering the powder coating product remaining in the tank 102 and flowing through the opening controlled by the sleeve valve 105.

[0046] This third position makes it easier and faster to drain the reservoir 102 and recover the coating product remaining in this reservoir, which facilitates a coating product change operation. Indeed, the coating product used previously can be recovered in its original carton 118, this carton being able to be stored until a next powder coating operation during which this product will be used. Changes of coating product, in particular color changes, are therefore facilitated.

[0047] The third position represented in the figure 4 is an intermediate position between the first position represented in figure 3 and the second position represented in figures 1 And 2 , in the sense that, when passing from the first position to the second position with a rotation in the trigonometric direction, and vice versa from the second position to the first position with a rotation in the anti-trigonometric direction, the support 120 passes through the third position.

[0048] This third position of the support 120 can be reached by the support 120, by a rotation in the direction of the arrow R1 from the first loading / unloading position, of lesser amplitude than that corresponding to the passage from the first loading / unloading position to the second transfer position. A rotation in the opposite direction makes it possible to move the support 120 from its third purge position to its first loading / unloading position. This third position of the support 120 can also be reached by the support 120, by a rotation in the direction of the arrow R2 from the second transfer position, of lesser amplitude than that corresponding to the passage from the second transfer position to the first loading / unloading position. A rotation in the opposite direction makes it possible to move the support 120 from its third purge position to its second transfer position.

[0049] In practice the angle β of rotation of the support 120, in the trigonometric direction in top view shown on the inserts B) of the figures 2 And 4 , between its first and third positions can be between 70 and 110°, preferably between 80° and 100°, more preferably of the order of 90°. Alternatively, the rotation of the support 120 between its first and third positions can be carried out in the anti-trigonometric direction in top view to reach the same point.

[0050] In the above, when an angle is defined as of the order of a value, it is equal to that value to within 5°.

[0051] Whatever the position of the support 120, at least one of the handles 132 and 134 is accessible to the operator from outside the carcass 104, through the opening O104, in order to exert a rotational torque around the axis Z120, in the direction of the arrow R1 or in the direction of the arrow R2, depending on the desired movement.

[0052] In the second embodiment shown in figures 5 and following, elements similar to those of the first embodiment bear the same references and are not described in detail. In the following, if a reference is mentioned in the description without being shown in a figure or if it is shown in a figure without being mentioned in the description, it corresponds to the same element as that bearing the same reference in the first embodiment. In the following, we mainly describe what distinguishes the second embodiment from the previous one.

[0053] This embodiment differs from the previous one in that a rigid container 119 is mounted on the support 120 in order to receive a bag of coating product, which corresponds to certain coating product packaging configurations sometimes called "big bags". The container 119 is preferably made of welded polymer, lacquered steel or polished stainless steel. This container 119 is closed by a cover 139 equipped with a tube 141 which forms a chimney through which a suction rod 122 plunges into the container 119, in order to take therefrom the sprayed coating product sucked by the pump 112 through the conduit 126, in the configuration of figures 5 And 6 where the support 120 is in a transfer position defined as in the first embodiment.

[0054] Parts 102 to 116 and 121 to 134 of the powdering station 2 are identical to those of the first embodiment.

[0055] In particular, the support 120 is movable in rotation, in the two directions represented by the arrows R1 and R2 respectively at figures 7 And 6 , between a first position for loading / unloading a bag of coating product into the tank 119 and a position for transferring coating product from the internal volume of the tank 119 to the sprayer 6, passing through the reservoir 102 of fluidized coating product.

[0056] In the first loading / unloading position of the support 120 shown in the figure 7 and according to an aspect which is not shown, the cover 139 is removed before evacuating a bag of partially or totally consumed coating product and before placing a new bag of coating product in the tank 119. After this operation, the cover 139 is replaced on the tank 119, still in this position.

[0057] The cover 139 and the tube 141 make it possible to confine the internal volume of the tank 119. This prevents powder coating product from being deposited on the internal parts of the supply unit 10. This limits the risks of pollution of this powder coating product by external particles.

[0058] The tube 141 is positioned on the cover 139 such that it is aligned with the suction rod 122 in the second transfer position shown in figures 5 And 6 , as well as with the outlet opening of the tank 102 controlled by the sleeve valve 105, in the third configuration shown in figure 8 , which is optional as in the first embodiment.

[0059] In this third position, the tube 141 ensures the guidance of the coating product towards the interior volume of the tank 119 and limits the risks of pollution of the volume V104.

[0060] Whatever the embodiment, the number of handles 132, 134 or equivalent equipping the support 120 to apply a rotational torque between its positions mentioned above, may be other than two, in particular equal to one or greater than or equal to three. In addition, these handles may have a geometry different from that shown in the figures.

[0061] Alternatively, the carcass 104 may have a geometry different from that shown in the figures and its opening may be oriented differently.

[0062] Alternatively, the movement of the support between its first and second positions and, possibly between these positions and the third position, is a circular translational movement, around two axes of rotation. In this case, the angle of rotation between the different positions is limited to 180°.

[0063] Whether with a rotational or circular translational movement, the movement of the support between its positions is well controlled and does not cause any obstruction of the space outside the carcass 104, which would be the case with a translational movement.

[0064] According to another variant not shown, applicable to a rotational or circular translational movement, means are provided for indexing, that is to say stopping, the support in each of its first and second positions, and possibly in its third position.

[0065] According to yet another variant not shown, the support 120 is driven electrically, by a motor, or pneumatically, by a rotary cylinder, between its positions. In this case, the handles 132 and 134 can be omitted.

[0066] The invention is not limited to the embodiments described. In particular, the embodiments and variants envisaged above can be combined with each other.

Claims

1. A feeding unit (10) for a powdering station (2), of powder coating product, said feeding unit comprising - a fluidized coating product reservoir (102); - a support (120) for receiving a container (118, 119) of coating product; - a pump (112) for feeding the fluidized coating product reservoir from the container carried by the support; and - a casing (104) which defines an internal volume (V104) for receiving the fluidized coating product reservoir and which is provided with an opening (0104) for access to this internal volume, characterized in that the support (120) is movable in rotation or circular translation about at least one axis of rotation (Z120), in both directions (R1, R2), at least between - a first loading / unloading position, wherein the support (120) projects outside the internal volume (V104) of the casing (104), through the access opening (O104); and - a second coating transfer position, wherein the support and a container (118, 119) in place on the support are included in the internal volume of the casing.

2. The feeding unit according to claim 1, characterized in that the axis of rotation (Z120) is vertical and preferably arranged, in part, within the internal volume (V104) of the casing (104).

3. The feeding unit according to any one of the preceding claims, characterized in that the support (120) is equipped with a vibrating table (121).

4. The feeding unit according to any one of the preceding claims, characterized in that the support (120) is movable in rotation or circular translation from one of its first and second positions toward a third position for purging the fluidized coating product reservoir (102), and vice versa from the third position toward one of its first and second positions.

5. The feeding unit according to claim 4, characterized in that, in the third position of the support, the coating product container (118, 119) is arranged below the fluidized coating product reservoir (102).

6. The feeding unit according to any one of the preceding claims, characterized in that an angle of rotation (α) of the support (120) between its first and second positions is between 100 and 180°, preferably between 120° and 160°, more preferably of the order of 135°, and in that, preferably, an angle of rotation (β) of the support, between its first and third positions is between 70 and 110°, preferably between 80° and 100°, more preferably of the order of 90°.

7. The feeding unit according to any one of the preceding claims, characterized in that the container (119) is equipped with a cover (139) provided with a tube (141) for the passage of a coating product suction tube (122) when the support is in its second position, and in that this tube is arranged below an opening (105) for emptying the fluidized coating product reservoir when the support is in its third position.

8. The feeding unit according to any one of the preceding claims, characterized in that the support (120) is equipped with at least one handle (132, 134) for moving the support in rotation (R1, R2) between its first and second positions, and optionally between these first and second positions and the third position.

9. The feeding unit according to any one of the preceding claims, characterized in that the support (120) is configured to receive containers of the tray type (119), in particular a rigid tray for a bag of coating product, or of the carton type (118).

10. A powdering station (2) comprising at least one powder coating product sprayer (6) installed in a spray booth (4) and supplied with coating product by a supply unit (10), characterized in that the supply unit (10) is according to one of the preceding claims.