EP2358480A1

EP2358480A1 - Station and method for reloading a mobile sprayer with coating material

Info

Publication number: EP2358480A1
Application number: EP09801750A
Authority: EP
Inventors: Patrick Ballu; Thierry Buquet; Cédric LE STRAT; Eric Prus; Hervé WALTER
Original assignee: Sames Technologies SAS
Current assignee: Sames Kremlin SAS
Priority date: 2008-12-09
Filing date: 2009-12-08
Publication date: 2011-08-24
Anticipated expiration: 2029-12-08
Also published as: FR2939335B1; EP2358480B1; JP2012511419A; KR101665074B1; CN102292162A; CN102292162B; BRPI0917613B1; ES2484323T3; US8584712B2; BRPI0917613A2; WO2010067015A1; FR2939335A1; US20110259431A1; KR20110104005A; JP5575796B2; RU2011128381A; RU2476274C1

Abstract

The invention relates to a station (S) for reloading a sprayer (1) provided with a tank (10), said station comprising: a means (121) for coupling to at least one coating material circuit (70-79); a clamping unit (200) that defines an area (250) for receiving a sprayer (1); at least one accumulator (110, 120, 130, 140, 150), the volume of which is greater than or equal to the volume of the tank (10), each accumulator (110, 120, 130, 140, 150) being connected to at least one respective circuit (20, 70-79) by the coupling means (121; 170-179); means (125, 120.1, 120.2) for pressurizing the accumulator (110, 120, 130, 140, 150); means (121, 123-153) for connecting each accumulator (110, 120, 130, 140, 150) to the clamping unit (200); and a member (222) for connecting the clamping unit (200) to the tank (10).

Description

STATION AND METHOD FOR REPAIRING PRODUCT

COATING A MOBILE PROJECTOR

The present invention relates to a station and a method for replenishing coating product at least one projector equipped with a reservoir and disposed on a mobile robot with respect to objects to be coated.

EP-A-0 274 322 discloses a coating product spraying apparatus on objects to be coated, such as motor vehicle bodies. By "coating product" is meant any product intended to be projected on an object to be coated, for example a primer, a paint, a varnish, etc. A station is used to refill coating product a projector equipped with a tank and placed on a mobile robot compared to car bodies. This station comprises means for connection to coating product circuits. The connection means are formed by connector elements each mounted at the end of a respective coating product circuit. Each circuit coating product can alternately feed the tank fitted to the projector.

The replenishment station described in EP-A-0 274 322 further comprises a docking unit defining a reception area for the projector equipped with its tank. After a projection phase on the objects to be coated, to replenish the projector and its reservoir coating product, the robot comes to place the projector in the reception area. Then, the tank is connected to the coating product circuit to be transferred into the tank via a corresponding connecting means of the docking unit. After filling the tank, the robot starts again to move the projector next to the objects to be coated.

When it is necessary to make a change of coating product, for example a change of color of paint, it is necessary, before filling, to rinse the projector and its reservoir with the cleaning product. For this purpose, the replenishing station described in EP-A-0 274 322 comprises another connector element fulfilling the function of connecting member to a cleaning product line. By «product cleaning means any suitable solvent to remove the coating product from the surfaces of the tank and the projector.

The prior art stations and processes achieve relatively long coating product changes because the pressure in conventional circuits is generally limited to 6 bar, which induces a tank fill rate of 3000 cm ³ / min. Thus, a replenishment lasts approximately 20 s for a 400 cm ³ tank, including 10 s for the docking of the headlamp and the connection of the tank to the docking unit. In the case of an installation for painting motor vehicle bodies, such a station and such a replenishment process can coat at most 50 vehicles / hour.

Moreover, to limit the sedimentation of a coating product, in particular a paint, when it stagnates in a circuit of a paint installation as described by WO-A-01 015 814, each coating product circuit must be composed of two separate strands to circulate the coating product regularly. A "go" strand brings the coating product from a pump to the station connection means, while a "return" strand returns the coating material from the connecting means to the pump. However, the costs of manufacturing, mounting and maintenance of such double-strand circuits are relatively high.

The present invention aims to overcome these disadvantages by providing a station for rapid replenishment, simple construction and limiting losses and sedimentation of coating products.

For this purpose, the subject of the invention is a station for replenishing coating product with at least one projector equipped with at least one reservoir and placed on a mobile robot with respect to objects to be coated.

The station comprises:

means for connecting to at least one coating product circuit;

- a docking unit defining a reception area for at least one projector;

The station also includes:

at least one accumulator whose volume is greater than or equal to the volume of the reservoir, the or each accumulator being adapted to be connected to at least one respective coating product circuit via the connecting means;

means for pressurizing the volume of the accumulator;

means for connecting the or each accumulator to the docking unit; and

- A connecting member of the docking unit to the tank.

According to other advantageous but optional features of the invention, taken separately or in any technically permissible combination: the station comprises a multipurpose accumulator connected to several circuits by means of connection means which comprise a product change block; coating, the multipurpose accumulator being connected, on the one hand, to the coating product change block and, on the other hand, to the docking unit; - The station comprises several accumulators each connected to a respective circuit via separate connecting means, the connecting member comprising, for each accumulator, a head valve configured for connection with the projector; the station further comprises at least one connecting member to at least one cleaning product line and that the docking unit further comprises a device for rinsing external surfaces of the headlamp, the device being connected to the line of cleaning product via the connecting member, the device being movable between several positions corresponding to the respective head valves; - The multipurpose accumulator is dedicated to the least frequently used coating products, while each other accumulator is dedicated to a coating product more often used; the or each accumulator operates in a reversible manner, so that it can transfer coating product either to the docking unit or to the connection means to the corresponding circuit; the pressurizing means comprise a connection and a respective thrust chamber belonging to the or each accumulator, the thrust chamber being intended to be pressurized so as to expelling the coating material from the corresponding accumulator, the fitting being adapted for connecting the thrust chamber to a compressed air line; the pressurizing means comprise a respective piston belonging to the or each accumulator, the piston delimiting the thrust chamber and being movable in translation in the corresponding accumulator; the station further comprises at least one pressure sensor for regulating the pressure in the or each accumulator and in the connection means.

Furthermore, the subject of the present invention is a method for restocking at least one projector equipped with at least one reservoir and placed on a mobile robot with respect to objects to be coated. The method implements a station. comprising: a docking unit defining a receiving area for at least one projector; at least one accumulator whose volume is greater than or equal to the volume of the reservoir, the or each accumulator being adapted to be connected to at least one respective circuit of coating product via connection means; means for connecting the or each accumulator to the docking unit; and a connection member of the docking unit to the tank; The method comprises the following steps: a) filling the or each accumulator with coating material via the connecting means; b) pressurizing the volume of the accumulator; c) place the projector in the reception area; d) connect the tank to the docking unit; e) transferring coating material from one of the accumulators to the docking unit so as to fill the tank. According to other advantageous but optional features of the invention, taken in isolation or in any technically permissible combination: step e) of filling consists of: f) isolating the accumulator from the circuit by closing the connection means; (g) effect the transfer at a transfer rate between

4000 cm ³ / min and 6000 cm ³ / min, the accumulator being put under a transfer pressure greater than the filling pressure prevailing in the circuit, the transfer pressure being between 10 bar and 30 bar, preferably equal to 15 bars; the method further comprises the steps of: h) prior to the placing step b), positioning a device for cleaning the exterior surfaces of the projector at a head valve corresponding to the accumulator for performing the step of transfer d); i) essentially during connection steps c) and transfer d), flush the outer surfaces of the projector by means of the device; the method further comprises the following steps: j) connecting the accumulator to the respective circuit by opening the connection means; k) driving back into the corresponding circuit the coating product contained in an accumulator, after a determined duration so as to limit the sedimentation of the coating product. The invention will be well understood and its advantages will also emerge in the light of the description which follows, given solely by way of nonlimiting example and with reference to the appended drawings, in which:

- Figure 1 is a perspective view of a station according to the invention; FIG. 2 is a perspective view, at a different angle, of the station of FIG. 1;

FIG. 3 is an enlarged view of detail III in FIG. 2;

- Figure 4 is a section along the plane IV in Figure 2; FIG. 5 is a view on a larger scale of detail V in FIG. 4.

FIG. 1 shows a station S comprising a docking unit 200 which defines a reception area 250 for a headlamp 1. The headlamp 1 is carried by a robot 2, whose envelope is symbolized in phantom. The robot 2 is movable so as to move the projector 1 relative to the objects to be coated, which may be automobile bodies moved by a conveyor, as shown in Figures 1 to 3 of EP-A-0 274 322.

The projector 1 is equipped with a tank 10 which is described as "internal" because it is incorporated in a body 11 defining the external envelope of the projector 1. When the projector 1 is in the reception zone 250, the station S can proceed to replenish the tank 10 coating product.

The docking unit 200 comprises a frame 201 and a plate 210 mounted at the top of the frame 201. The frame 201 and the plate 210 support a part of the components of the docking unit 200, as well as some other components of station S.

The station S further comprises five accumulators 110, 120, 130, 140 and 150 which are stationary relative to the station S. The accumulators 110, 120, 130, 140 and 150 have identical structures, so that only the structure of the accumulator 120 will be detailed below. The description given below of the accumulator 120 and its peripheral components can be directly transposed to the accumulators 110, 130, 140 and 150, with the exception of the differences explicitly mentioned concerning the accumulator 150.

The accumulators 110, 120, 130 and 140 are arranged in the lower part of the frame 201, while the accumulator 150 is mounted near the plate 210. Each accumulator 110, 120, 130, 140 and 150 has a substantially tubular shaped body. circular base. The accumulators 110, 120, 130 and 140 extend vertically and juxtaposed, while the accumulator 150 extends horizontally. The accumulators 110, 120, 130 and 140 thus form a set of accumulators 100. Each accumulator 110, 120, 130, 140 or 150 is made of an electrically conductive material, for example metal, and brought to the electric potential of the earth. by means of conducting wires or fastening screws (not shown), so as to ensure the safety of the operators. As shown in Figure 4, the tubular body of the accumulator 120 has a volume V120 which is delimited at both ends by respective flanges 127 and 128. The accumulator 120 is connected to a circuit 20, symbolized in phantom in Figure 4, which contains a coating product, in this case a liquid paint of specific color. The accumulator 120 is connected to the circuit 20 via a connection 121 on which is fixed the tip of the circuit 20. The connection 121 forms a connection means of the accumulator 120 to the circuit 20.

In the present application, the verbs "connect", "connect" and "connect" refer to a fluid communication, that is to say to a link that allows a fluid, gaseous or liquid, to flow. or to move between two or more points or parts. Such a link can be direct or indirect, that is to say realized by a pipe, a pipe, a pipe and so on. Similarly, the nouns derived from these verbs, such as "connection" and "connection" relate to such fluid communication.

Like the accumulator 120, each accumulator 110, 120, 130 and 140 is connected to a respective painting circuit, such as the circuit 20, not shown, by means of respective connectors visible in FIG. not referenced. In other words, each accumulator 110, 120, 130 or 140 may be dedicated to a specific shade of paint.

The circuit 20 has the first function of supplying the accumulator 120 with paint. Such a circuit is usually designated by the English word "circulating". The circuit 20 may be formed by a flexible pipe, in which the paint is subjected to a pressure of about 6 bar by a pump not shown. The circuit 20 belongs to the paint spray installation in the same way as the station S.

On the other hand, the accumulator 120 is connected to the docking unit 200 by connection means which comprise a coupling 122, a pipe 123 and a coupling 222.1. The coupling 122 is fixed in the flange 127. The coupling 222.1 is fixed in a base 220 belonging to the docking unit 200. The pipe 123 extends between the connectors 122 and 222.1.

The base 220 is disposed on the plate 210 near the receiving zone 250. As shown in FIG. 3, the base 220 includes several head valves juxtaposed, including the head valves 221, 222, 223, 224 and 225 which respectively correspond to the accumulators 110, 120, 130, 140 and 150. Each valve 221, 222, 223, 224 or 225 has a conventional structure and it is maneuvered by unrepresented pneumatic members. Alternatively, each valve 221, 222, 223, 224 or 225 may be configured to be operated by the projector 1, either mechanically or by means of a pneumatic control, which makes it possible to open the valve 221,

222, 223, 224 or 225 respectively after connection of the projector 1.

As shown in Fig. 5, the head valve 222 controls, i.e., allows or prevents, product flow in an output channel 232. The output channel 232 is defined in the base 220 where it forms the downstream end of the docking unit 200, therefore of the station S. Each head valve 221, 222,

223, 224 or 225 form a connecting member of the docking unit to the tank 10. In practice, the head valve 222 or equivalent connects an outlet channel 232 or equivalent of the base 220 to the tank 10 via the headlight 1.

To replenish its tank 10, the projector 1 must be connected to an output channel 232 or equivalent. The selected output channel is the one that matches the required paint tint.

In the present application, the terms "downstream" and "upstream" are used by reference to the flow direction of the fluid, coating product, compressed air or cleaning product.

Unlike the accumulators 110, 120, 130 and 140, the accumulator 150 is connected to several circuits 70 to 79 where different coating products circulate, in this case paints of different hues. The paint circuits 70 to 79 are shown in phantom in Figures 1 and 2.

The accumulator 150 is connected to the circuits 70 to 79, in particular via a block 152 for changing the coating product. Block 152 has a conventional structure and functions.

As shown in FIG. 1, the block 152 is composed of a juxtaposition of several elementary modules 160 to 169, at the rate of one elementary module 160 to 169 per circuit 70 to 79. On each elementary module 160 to 169 is fixed a connection 170 to 179 respectively. The ends of the paint circuits 70 to 79 are respectively fixed in the connections 170 to 179. The means for connecting the accumulator 150 to the paint circuits 70 to 79 comprise the block 152 and the connections 170 to 179.

These connection means also comprise a connection 151 fixed in a flange 157 mounted at one end of the accumulator 150. The connection 151 is connected to the block 152 via a pipe 154 which is shown in phantom in the figure 2.

In addition, as shown in FIGS. 1, 2 and 4, the accumulator 150 is connected to the base 220 via connection means which comprise: a connector 156 fixed in the flange 157;

a connector 225.1 fixed in the base 220 and similar to the coupling 222.1;

a pipe 153 which extends between the connections 156 and 225.1.

Since the accumulator 150 is connected to several paint circuits 70 to 79, it is described as "versatile". In other words, the accumulator 150 is not dedicated to a specific paint, but to several different paints having different hues. The accumulator 150 is dedicated to the less frequently used paints, while each accumulator 110, 120, 130 or 140 is dedicated to a hue paint more often used. In other words, the accumulator 150 is dedicated to so-called "rare" shades, while each accumulator 110, 120, 130 or 140 is dedicated to a so-called "main" shade.

Furthermore, the docking unit 200 comprises a device 251 for rinsing the outer surfaces of the projector 1. The device 251, known per se, is connected to a not shown cleaning product line, via a connecting member or connector 252 visible in Figure 1. The receiving zone 250 comprises the upper rectangular opening of the frame 201, through which a portion of the projector 1 can pass to enter the device 251. In addition, the device 251 is connected to a not shown compressed air line, so as to dry the previously injected cleaning product.

The device 251 is mounted on a carriage 253 which is movable in translation relative to the frame 201, along the double-arrow X ₂₅ I, by means of a not shown actuator. The device 251 is thus movable between positions corresponding to the alignment of the body 11 of the projector 1 on each head valve 221, 222, 223, 224 or 225 respectively. In addition, the docking unit 200 comprises a jack 215 configured to move the plate 210, thus the base 220, in translation along the double-arrow X220, so as to connect and disconnect the base 220 and the projector 1.

As shown in Figures 2 and 3, the docking unit 200 further comprises a plate 204 secured to the docking unit 200. When connecting the projector 1, the plate 204 is located opposite the end Distal from the projector 1. The plate 204 is fixed on the carriage 253, so that it is also movable in translation relative to the frame 201 according to the double arrow X251. The adjective "distal" designates an element of the projector 1 relatively far from the robot 2, while the adjective "proximal" designates an element that is closer to it.

The plate 204 has a through opening 206. The plate 204 has a lug 207 on each of its faces, so as to guide the projector 1 and the base 220 to make a sealed contact. The plate 204 serves as an interface between the projector 1 and the docking unit 200, more precisely each head valve 221, 222, 223, 224 or 225.

When connecting the docking unit 200 to the projector 1 and its reservoir 10, on the one hand, the cylinder 215 moves the plate 210 until the contact between the base 220 and the plate 204. The plate 204 and the head valve 222 are placed in sealing contact by a relative movement, which can be carried out in translation by the robot 2 and / or by the cylinder 215. When one of the lugs 207 has penetrated into a corresponding bore of the valve of head 222, the output channel 232 is connected to the port 206.

On the other hand, the robot 2 places the projector 1 near the plate 204. A valve 12 is incorporated in the projector 1 to control the replenishment of the reservoir 10. The plate 204 and the distal portion 13 of the valve 12 are brought into contact with each other. sealed by a relative movement, which can be carried out in translation by the robot 2 and / or by the cylinder 215.

Each accumulator 120 or equivalent comprises a piston 120.2 and a thrust chamber 120.1. The piston 120.2 is movable in translation in the accumulator 120. The thrust chamber 120.1 is delimited by the piston 120.2 and by the walls of the accumulator 120. The paint is contained in the chamber, referenced V120, which is delimited by the piston 120.2 and which is situated above the thrust chamber 120.1. Alternatively, the chamber of thrust 120.1 can be placed above the chamber containing the paint.

The thrust chamber 120.1 is intended to be pressurized to exert a pressing force F ₁₂ o on the piston 120.2, so as to expel the paint from the accumulator 120. To increase the pressure in the thrust chamber 120.1, a pressure fluid, in this case compressed air, is supplied by the air duct 25. The air duct 25 is connected to the flange 127 via a coupling 125, then to the flange 128 by through a conduit and a fitting not shown. The thrust fluid flows from the pipe 25, in the connection 125, then into the flange 127, before being introduced into the thrust chamber 120.1, via the pipe and the connection not shown. Alternatively, a type connection 125 can be mounted directly on the flange 128.

An unillustrated pneumatic distributor, such as a three-way valve, controls the inflow of compressed air into the thrust chamber 120.1, via the air line 25. This pneumatic distributor also controls the escape of the compressed air outside the thrust chamber 120.1, preferably in the atmosphere, to cancel the thrust force F ₁₂ o, which allows to fill the accumulator 120 in paint.

Each accumulator 110, 120, 130, 140 or 150 operates reversibly, that is to say it can transfer paint either to the docking unit 200 via the pipe 123 and the coupling 122, or to the circuit 20 through the connector 121. The selection of the direction of the paint delivered by the accumulator 120 is by means of a selection valve 129.1 housed in the flange 127. The selection valve 129.1 can alternately and simultaneously close the connections 121 and 122. The valve 129.1 thus controls the arrival of paint in the accumulator 120 from the paint circuit 20, as well as the exit of the paint from the accumulator 120 towards the pipe 123.

The pipes 123 and 153, which connect the base 220 respectively to the accumulators 110, 120, 130, 140 and 150, have relatively short lengths, which makes it possible to minimize the pressure losses in the flow of the paint, therefore of limit the duration of replenishment of the tank 10 by the accumulator 120 or equivalent. The station S operates according to a replenishment method according to the invention. This method comprises a step of performing, in masked time, the filling of one or more of the accumulators 110, 120, 130, 140 and 150, according to the paint colors selected for the next cycle (s) ( s) paint projection. For example, the accumulator 120 is filled with the paint which is in the circuit 20. The expression "in masked time" indicates that the step is carried out during a paint projection cycle, that is to say say without slowing down the rate of the paint installation. To perform this filling, the pneumatic distributor is piloted at the exhaust, so as to establish in the accumulator 120 a pressure lower than the pressure in the pipe 20. The thrust force F ₁₂₀ is zero and the paint may enter the accumulator 120 by pushing the piston 120.2. In this state, the pressure in the accumulator 120 is the same as the pressure in the circuit 20, typically 6 bars.

Then the selector valve 129.1 is piloted to "open" the connector 121, so that the paint flows from the line 20 into the accumulator 120. As the piston 120.2 does not withstand the entry of the paint into the chamber. 120, the filling of the accumulator 120 can be performed in masked time, during the phase of projection of paint by the projector 1. When coating a body, the projection phase lasts about 1 min.

To completely fill the volume Vi ₀ of the tank 10, the volume Vi ₂ o of the accumulator 120 or equivalent must be greater than or equal to the volume Vi ₀ . For example, for a volume to be filled V ₁₀ of 400 cm ³ , it is possible to use an accumulator 120 whose volume V ₁₂₀ is 600 cm ³ , or even 1000 cm ³ .

After filling the accumulator 120, the connection 121 is closed by controlling the selector valve 129.1 so as to interrupt the flow communication between the recess 20 and the accumulator 20. or equivalent. The accumulator 120 is then isolated from the circuit 20. Then, the pressurizing means of the volume V ₁₂ o is actuated: a pneumatic distributor is fitted to the thrust chamber 120.1 via the connector 125, so as to increase the pressure in the accumulator 120, to a pressure substantially greater than the pressure of the circuit 20. When the thrust chamber 120.1 of the accumulator 120 is at a pressure of approximately 15 bar, the accumulator 120 is ready to deliver the paint it contains to the docking unit 200, to replenish the tank 10.

Thus, the coupling 125 and the thrust chamber 120.1 form means for pressurizing the volume V ₁₂ o of the accumulator 120 or equivalent, at a pressure (15 bar) strictly greater than the pressure prevailing in the circuit 20 ( 6 bars).

At the end of a paint projection cycle, after the step of filling the accumulator 120 or equivalent, the connection of the projector 1 and the base 220 is made, by moving the robot 2 and the plate 210 towards 204. More precisely, the headlamp 1 and the base 220 are brought together until the contact between the plate 204, on the one hand, and the front part 13 of the valve 12 and the head valve 222, 'somewhere else.

The volume Vi ₀ is brought to a low or zero relative pressure, for example at atmospheric pressure. Then "fitting" 122 is opened to dispense the paint in the pipe 123 to the tank 10 via the docking unit 200.

When the reservoir 10 is filled, the projector 1 and the base 220 are disconnected and the robot releases the projector 1 out of the reception area 250. The projector 1 thus leaves the station S to join the paint projection space.

At the end of a paint spray cycle, the tank 10 fitted to the projector 1 is partially or totally empty. It is then necessary to refill the reservoir 10 in paint, filling it as described above. For this purpose, the robot 2 places the projector 1 in the reception zone 250.

Previously, the device 251 is positioned at the head valve 222 corresponding to the accumulator 120 or equivalent which is intended to carry out the transfer of paint according to the selected shade. When the projector 1 is in the device 251, it controls the emptying of any paint residue out of the tank 10. This paint residue is collected by the device 251 and then routed to a waste treatment center not shown.

When it is necessary to change the color of the paint, the inside of the tank 10 is rinsed by means of a solvent line, not shown, which can be connected to the plate 204. As is known per se, the device 251 cleans, with solvent brought via the connection 252, the outer surfaces of the part of the projector 1 which carries the projection member and which may have been soiled. .

As described above, when the thrust chamber 1 20.1, thus the paint contained in the volume V ₁₂₀ of the accumulator 120, is pressurized, the head valve 222 and the coupling are "opened". 121, by the selector valve 129.1, so that the paint flows from the accumulator 120 into the reservoir 10 via the pipe 123, which transfers the paint from the accumulator 120 to the unit 200 and the tank 10. The flow rate of this transfer from the volume Vi ₂₀ to the volume Vi ₀ depends on the pressure prevailing in the volume V ₁₂₀ or equivalent. When the volume V ₁₂ o is placed under 15 bars of pressure via the coupling 125, the filling rate of the volume Vi ₀ can reach 6000 cm ³ / min during the entire replenishment phase of the reservoir 10. Such a flow rate of filling makes it possible to fill a volume V ₁₀ of 400 cm ³ in less than 5 s. This filling time, added to the docking time of the projector 1, makes it possible to mimic the total duration of replenishment of the projector 1 to less than 12 seconds. By "total duration of replenishment" means the time between the stop and the resumption of the projection of paint on the objects to be coated.

A station and a method according to the present invention therefore make it possible to achieve a replenishment of substantially shorter duration than the stations and methods of the prior art. The duration of change of hue is thus also shortened. Therefore, a station and method according to the present invention can achieve a projection rate of about 60 to 70 vehicles / hour.

In practice, the transfer pressure may be between 10 bar and 30 bar and the transfer rate may be between 4000 cm ³ / min and 6000 cm ³ / min. In the present application, the mentioned pressures are relative and static pressures.

To regulate this pressure of 15 bar prevailing in the accumulator 120 or equivalent, as well as in the connection means such as the pipe 123 or 153, the station S further comprises at least one pressure sensor 208 shown diagrammatically in FIG.

Moreover, in a paint installation, the selection of the paint color to be sprayed on each body of a motor vehicle is carried out by a supervision unit. This supervision unit defines highly variable hue sequences, so that a hue may not be selected for a relatively long time, during which the paint stagnates in one or more of the accumulators 110, 120, 130, 140 or 150.

To limit the sedimentation of this stagnant paint, a process according to the invention also comprises a step during which the stagnant paint in the accumulator 1 10, 120, 130, 140 or 150 is forced back into the respective paint circuit. , after a duration that is determined according to the characteristics of the painting.

In order to effect this backflow of paint, the accumulator 120 or equivalent is connected to the circuit 20 by opening the connection 121 by means of the selection valve 129.1. As the volume Λ ₂ o is at a higher pressure, typically 15 bar, at the pressure in the circuit 20, typically 6 bar, the paint flows from the accumulator 120 to the circuit 20, until complete emptying volume v ₁₂ o- This discharge thus limits the stagnation of paint in the accumulator 120 or equivalent. Subsequently, it is possible to refill the accumulator 120, following the steps described above, to respond to a command from the supervision unit.

According to a variant not shown, instead of repressing the paint through the connector 121, a station according to the invention may comprise, for each accumulator, a specific connection and discharge pipe whose supply is controlled by valves.

Furthermore, a station according to the invention may comprise, for each accumulator, a circuit and a so-called "purge" valve, in order to recover the solvent circulated in the accumulator during the cleaning phase. This reversible operation of the accumulators limits the sedimentation of paint. Thus, a replenishing station according to the invention can be connected to coating product circuits each composed of a single strand for the "out" and "return" circulation of the coating product. Nevertheless, a replenishing station according to the invention can be connected to double-strand coating product circuits, a "go" strand and a "return" strand, which generally exist in a conventional paint installation. In addition, a replenishing station according to the invention does not require coating product circuits with increased dimensions, because they are brought to usual pressures, of the order of 6 bars.

The structure of the station and that of the installation of which it forms part are therefore simpler than those of the prior art, which substantially reduces the costs of manufacture, assembly and maintenance.

On the other hand, despite complex hue sequences, a station and method in accordance with the present invention improves the handling of paints of different hues, since "rare" hues are supported by the multi-purpose accumulator and because "main" shades are taken care of by dedicated accumulators. This improved management of paints of different colors also makes it possible to reduce the losses of coating product and cleaning product.

Station S has been represented with five dedicated accumulators. However, a replenishment station according to the invention may comprise as many dedicated accumulators as "main" shades. For example, a replenishment station according to the invention may comprise between one and thirty dedicated accumulator (s), preferably sixteen.

According to a variant not shown, the means for pressurizing the volume of each accumulator comprises a thrust chamber formed directly above the coating product. Such an accumulator is devoid of piston and the compressed air then exerts its pressure directly on the coating product that it expels out of the accumulator. Each accumulator then functions as a pressure pot.

Claims

Station (S), for restocking at least one projector (1) equipped with at least one reservoir (10) and arranged on a robot (2) movable with respect to objects to be coated, the station ( S) comprising:

connection means (121, 170-179) to at least one coating material circuit (20, 70-79);

- a docking unit (200) defining a receiving area (250) for at least one projector (1); the station (S) being characterized in that it further comprises:

- at least one accumulator (110, 120, 130, 140, 150) whose volume (V ₁₂ o) is greater than or equal to the volume (Vi ₀ ) of the reservoir (10), the or each accumulator (110, 120, 130 , 140, 150) being adapted to be connected to at least one respective coating material circuit (20, 70-79) via the connecting means (121, 170-179);

means (125, 120.1, 120.2) for pressurizing the volume (V ₁₂ o) of the accumulator (110, 120, 130, 140, 150);

connection means (121, 123-156, 153) of the or each accumulator (110, 120, 130, 140, 150) to the docking unit (200); and

- a connecting member (221, 222, 223, 224, 225) of the docking unit (200) to the tank (10).

2. Station (S) according to claim 1, characterized in that it comprises a multipurpose accumulator (150) connected to several circuits (20, 70-79) via connecting means (170-179) which comprise a coating product changing block (152), the multipurpose accumulator (110, 120, 130, 140, 150) being connected, on the one hand, to the coating product changing block (152) and, on the other hand, to the docking unit (200).

3. Station (S) according to claim 1 or 2, characterized in that it comprises several accumulators (110, 120, 130, 140) each connected to a respective circuit (20) via connection means (121). ) separate, the connecting member (221, 222, 223, 224, 225) comprising, for each accumulator (110, 120, 130, 140, 150), a head valve configured for connection with the projector (1).

4. Station (S) according to claim 3, characterized in that it further comprises at least one connecting member (252) to at least one cleaning product line and that the docking unit (200) further comprises a device (251) for rinsing outer surfaces of the projector (1), the device (251) being connected to the cleaning product line via the connecting member (252), the device ( 251) being movable between several positions corresponding to the respective head valves.

5. Station (S) according to claims 2 and 3 or 4, characterized in that the multipurpose accumulator (150) is dedicated to the least frequently used coating products, while each other accumulator (110, 120, 130, 140 ) is dedicated to a coating product more often used.

6. Station (S) according to one of the preceding claims, characterized in that the or each accumulator (110, 120, 130, 140, 150) operates reversibly, so that it can transfer the coating product is to the docking unit (200) or to the connecting means (121, 170-179) to the corresponding circuit (20, 70-79).

7. Station (S) according to one of the preceding claims, characterized in that the means (125, 120.1, 120.2) for pressurizing comprise a connection (125) and a respective thrust chamber (120.1) belonging to the each accumulator (110, 120, 130, 140, 150), the thrust chamber (120.1) being intended to be pressurized so as to expel the coating material from the accumulator (110, 120, 130, 140, 150), the fitting (125) being adapted for connection of the thrust chamber (120.1) to a compressed air line (25).

Station (S) according to Claim 7, characterized in that the pressurizing means (125, 120.1, 120.2) comprise a respective piston (120.2) belonging to the or each accumulator (110, 120, 130, 140, 150), the piston (120.2) delimiting the thrust chamber (120.1) and being movable in translation in the corresponding accumulator (110, 120, 130, 140, 150).

9. Station (S) according to one of the preceding claims, characterized in that it further comprises at least one pressure sensor (208) for regulating the pressure in the or each accumulator (110, 120, 130, 140 , 150) as well as in the connection means (121, 123 - 156, 153).

Method for restocking at least one projector (1) equipped with at least one reservoir (10) and disposed on a robot (2) movable with respect to objects to be coated, the method being characterized in that it implements a station (S) comprising: a docking unit (200) defining a reception zone (250) for at least one projector (1); at least one accumulator (110, 120, 130, 140, 150) whose volume (V ₁₂ o) is greater than or equal to the volume (V ₁₀ ) of the reservoir (10), the or each accumulator (110, 120, 130, 140, 150) being adapted to be connected to at least one respective coating material circuit (20, 70-79) via connecting means (121, 170-179); connection means (121, 123-156, 153) of the or each accumulator (110, 120, 130, 140, 150) to the docking unit (200); and - a connection member (221, 222, 223, 224, 225) of the docking unit (200) to the tank (10); the method being characterized in that it comprises the following steps: a) filling the or each accumulator (110, 120, 130, 140, 150) with coating material via the connecting means (121, 170-179); b) pressurizing the volume (V ₁₂ o) of the accumulator (110, 120, 130, 140, 150); c) placing the projector (1) in the receiving area (250); d) connecting the tank (10) to the docking unit (200); e) transferring coating material from one of the accumulators (110, 120, 130, 140, 150) to the docking unit (200) so as to fill the reservoir (10).

11. The method of claim 10, characterized in that the filling step e) comprises: f) isolating the accumulator (110, 120, 130, 140, 150) of the circuit (20, 70-79) by sealing the connecting means (121, 170-179); g) perform the transfer at a transfer rate between 4000 cm ³ / min and 6000 cm ³ / min, the accumulator (1 10, 120, 130, 140, 150) being put under a transfer pressure greater than the pressure filler prevailing in the circuit (20, 70-79), the transfer pressure being between 10 bar and 30 bar, preferably 15 bar.

12. Method according to one of claims 10 to 1 1, characterized in that it further comprises the following steps: h) before the placement step b), position a device (251) for cleaning the outer surfaces of the projector (1) at a head valve corresponding to the accumulator (110, 120, 130, 140, 150) for performing the transfer step d); i) essentially during connection steps c) and transfer d), flush the outer surfaces of the projector (1) by means of the device (251).

13. Method according to one of claims 10 to 12, characterized in that it further comprises the following steps: j) connecting the accumulator (1 10, 120, 130, 140, 150) to the circuit (20, 70 -79) respectively by opening the connection means (121, 170-179); k) driving the coating product contained in an accumulator (1 10, 120, 130, 140, 150) into the corresponding circuit (20, 70-79) after a period of time so as to limit the sedimentation of the coating product.