EP1207964A1

EP1207964A1 - Method and station for changing product in a installation spraying coating product

Info

Publication number: EP1207964A1
Application number: EP00958682A
Authority: EP
Inventors: Caryl Thome; Philippe Provenaz; Louis Sentis
Original assignee: Sames Technologies SAS
Current assignee: Sames Kremlin SAS
Priority date: 1999-08-30
Filing date: 2000-08-11
Publication date: 2002-05-29
Anticipated expiration: 2020-08-11
Also published as: KR20020028222A; PT1207964E; KR100695867B1; CA2382699A1; DE60015569D1; BR0013587B1; US20020124799A1; DE60015569T2; CN1371308A; ATE281245T1; ES2230153T3; CN1158143C; US20020158149A1; FR2797788A1; EP1207964B1; US6391392B1; WO2001015814A1; TW526096B; US6702893B2; BR0013587A

Abstract

A process and station for changing product in an installation for spraying coating product, by bringing a first reservoir towards a suitable area of a cleaning/filling station, separating a sub-assembly composed of the first reservoir and a first spray associated therewith, with respect to the robot, connecting with the robot a second, similar sub-assembly composed of a second reservoir and a second spray, adapted to be used for spraying coating product during cleaning and/or filling of the first reservoir and the first spray, and proceeding with cleaning and/or filling of the first reservoir and the first spray in the area.

Description

PRODUCT CHANGE METHOD AND STATION IN A COATING PRODUCT SPRAYING INSTALLATION

The invention relates to a method and a product change station in a coating product spraying installation.

It is known, for example from EP-A-0 274 322, to use a reservoir, mounted at the end of an arm of a multi-axis robot, to supply coating product to a projector supported by this arm, in particular in the case of an installation for spraying an electrically conductive coating product by means of a projector of an electrostatic type. This state of the art provides for using a fixed projector on the robot arm and for cleaning and filling it with new coating product as required. According to a variant, the reservoir is removably mounted on the projector and several reservoirs are used depending on the coating product chosen. Finally, according to a second variant, two tanks are used alternately. In all cases, it is necessary to clean and prime the new coating product with the projector which is permanently mounted on the robot arm. These rinsing and priming operations for the headlight are relatively long, while the time allocated for changing the coating product tends to decrease. Indeed, in the case of a production chain of motor vehicles, the trend is to increase the production rates and therefore the advance speeds of the conveyors, the change of coating product being effected in a time interval. corresponding to the space separating two consecutive vehicle bodies, the available time being all the more reduced as the conveying speed increases.

It is to these problems that the invention intends to respond by proposing a new process and a new coating product change station which allow rapid change while the quality of the cleaning carried out remains optimal.

In this spirit, the invention relates to a method of change of product in a coating product installation, comprising at least one robot, capable of moving a first projector and a first associated reservoir facing objects to be coated, this method comprising a step of bringing this reservoir towards a zone adapted from a cleaning / filling station, characterized in that it consists in: separating a sub-assembly comprising the first tank and the first projector relative to the robot;

- securing with this robot a second similar sub-assembly comprising a second tank and a second projector, this second sub-assembly being suitable for being used for spraying coating product during the cleaning and / or filling of the first tank and the first headlamp and - clean and / or fill the first tank and the first headlamp in this area.

Thanks to the invention, the first tank can be cleaned and filled with new coating product in masked time. The projector is also cleaned, in masked time, and primed with the new coating product, so that the only steps in the cleaning / filling process that must be taken into account in calculating the duration of the change of product are the steps of separation of the first sub-assembly and of joining of the second sub-assembly on the arm of the robot. In other words, the time which was hitherto consumed for cleaning the projector and its priming as a new coating product is now available for projection by means of the second sub-assembly since these operations take place in masked time, on the first subset while the second subset is in use.

According to a first advantageous aspect of the invention, the method consists in supplying the first sub-assembly with air, cleaning product and / or coating product in the suitable zone of the cleaning / filling station, before its separation from with the robot. Thus, certain functions of the projector and / or of the tank can be kept there. understood during the separation between this sub-assembly and the robot.

According to another advantageous aspect of the invention, the sub-assembly is supplied with air, electric current, cleaning product and / or coating product by means of two mobile units, a first unit being connected to the sub-assembly before its separation from the robot while a second unit is connected to the sub-assembly after its separation from the robot, instead of the connection part of the robot.

In particular, provision may be made to permanently supply the projector with air forming a bearing between parts in relative movement of the projector, which proves to be particularly advantageous in the case of a rotary projector, since the supply continuous bearing prevents any risk of tightening or seizing of this bearing.

The invention also relates to a product changing station in a coating product spraying installation which makes it possible to implement the method as described above. This station, which comprises at least two zones for cleaning / filling a reservoir, is characterized in that these zones are each capable of receiving a sub-assembly formed by a reservoir and a sprayer while this sub-assembly is detached from the robot, means being provided for cleaning and / or filling the tank and the sprayer in each of these zones.

Thus, the cleaning and / or filling of each sub-assembly can take place in masked time, while a similar sub-assembly is in use on the robot. According to a first advantageous aspect of the invention, the means for cleaning / filling the tank and the projector comprises two mobile units able to be connected independently in two connection zones of the sub-assembly, a first unit being able to be connected to the sub - assembly mounted on the robot while the second unit is able to be connected to the sub-assembly in place of the connection part of the robot. The first unit advantageously comprises means of connection between an air source compressed and a bearing formed in the projector, between two parts in relative motion. Thus, the bearing can be powered permanently, which avoids the risks of seizing or tightening of this bearing. In particular, the second unit may include a jack, the rod of which is capable of operating a piston of the reservoir, in particular for the purging of this reservoir.

According to another advantageous aspect, the station comprises means for locking a sub-assembly in each of the cleaning / filling zones, by rotation of a ring surrounding this sub-assembly, and capable of cooperating with reliefs of this sub -assembly to move it in rotation relative to the robot. This ring is advantageously controlled in movement, between a locking position and an unlocking position of the sub-assembly, by a jack.

The invention will be better understood and other advantages of it will appear more clearly in the light of the following description of an embodiment of a product change station and its method of implementation in accordance to the invention, given solely by way of example and made with reference to the accompanying drawings in which:

- Figure 1 is a schematic representation of the principle of an installation for spraying coating product during operation;

- Figure 2 is a perspective view with partial cutaway of the product change station of the installation of Figure 1 during a first step of the method of the invention; - Figure 3 is a similar view of Figure 2 during a second step of the method of the invention;

- Figure 4 is a section on plane IV in Figure 3;

- Figure 5 is a section similar to Figure 4 during a third step of the method of the invention;

- Figure 6 is a view similar to Figure 2 during a fourth step of the method of the invention;

- Figure 7 is a view similar to Figure 2 during a fifth step of the method of the invention;

- Figure 8 is a view similar to Figure 2 during a sixth step of the method of the invention;

- Figure 9 is a view similar to Figure 2 during a seventh step of the method of the invention;

FIG. 10 is a section on plane X in FIG. 9 and

- Figure 11 is a view similar to Figure 2 during an eighth step of the method of the invention. In FIG. 1, an automaton or robot 1 is placed near a conveyor 2 transporting objects to be coated, in this case bodies 3 of motor vehicles. The robot 1 is of the multi-axis type and comprises a chassis 4 movable on a guide 5 'extending parallel to the conveying direction X-X'. An arm 6 is supported by the chassis 4 and comprises several segments 6a, βb and 6ç_ articulated with respect to each other. The chassis 4 also consists of parts 4a and 4b articulated with respect to each other around a substantially vertical axis Z. The segment 6c of the arm 6 supports a subassembly 7 in which a reservoir 8 of coating product and a projector 9 are provided. The projector 9 is of the electrostatic and rotary type and it carries a bowl 9a intended to be driven at high speed by an air turbine provided in the projector 9.

When a motor vehicle body 3 is in place at the level of the robot 1, the subassembly 7 is moved opposite the body and the headlight 9 is activated in order to coat this body with the product contained in the reservoir 8. The the quantity of product present in the reservoir 8 is adapted to the surface to be coated of the bodywork 3.

At the end of the coating of a body, and while a second body is in the process of progressing towards the robot 1, the latter is oriented towards a cleaning / filling station 10 located in its vicinity, inside the projection booth.

As appears more clearly in FIG. 2, this station 10 is provided with two zones 11 and 12 for receiving during a fifth step of the method of the invention;

FIG. 10 is a section on plane X in FIG. 9 and

- Figure 11 is a view similar to Figure 2 during an eighth step of the method of the invention. In FIG. 1, an automaton or robot 1 is placed near a conveyor 2 transporting objects to be coated, in this case bodies 3 of motor vehicles. The robot 1 is of the multi-axis type and comprises a chassis 4 movable on a guide 5 'extending parallel to the conveying direction X-X'. An arm 6 is supported by the chassis 4 and comprises several segments 6a, 6b and 6ç_ articulated with respect to each other. The chassis 4 also consists of parts 4a and 4b articulated with respect to each other around a substantially vertical axis Z. The segment 6ç_ of the arm 6 supports a subassembly 7 in which a reservoir 8 of coating product and a projector 9 are provided. The projector 9 is of the electrostatic and rotary type and it carries a bowl 9a intended to be driven at high speed by an air turbine provided in the projector 9.

As appears more clearly in FIG. 2, this station 10 is provided with two zones 11 and 12 for receiving sub-assemblies of the type of sub-assembly 7. More specifically, the zone 11 is empty and ready to accommodate the sub-assembly 7, while the zone 12 contains a similar sub-assembly 7 ′ which comprises a reservoir 8 ′ and a projector 9 'similar to those of the subassembly 7. The subassemblies 7 and 7' can be alternately mounted on the segment 6ç_ of the arm 6, as will be seen from the explanations which follow.

In the process step represented in FIG. 2, the arm 6 is in an approach phase in which it brings the subassembly 7 above the zone 11 of the station 10. From the position represented at FIG. 2, the arm 6 gives the sub-assembly 7 a vertical downward movement represented by the arrow F _{1 #} which makes it possible to bring the sub-assembly 7 into the zone 11 as shown in FIG. 3. A jack 13 allows to order a rod 14 secured to two links 15 and 16 themselves secured to crowns 17 and 18 disposed respectively around the outlets 11a and 12a of the zones 11 and 12. In fact, the zones 11 and 12 are formed by receptacles 11b and 12b, of internal shape adapted to the external shape of the subassembly 7 and 7 ', and which are connected by evacuation ducts 11c and 12c to a drain not shown.

The subassembly 7 is mounted on the segment 6c of the arm 6 by means of a ring 7a capable of a rotational movement around the axis X _x of the subassembly 7.

When the sub-assembly 7 is in place in the zone 11, the jack 13 is activated so that the rod 14 is moved axially as shown by the arrow F ₂ in FIG. 3, which has the effect of causing the rods 15 and 16 and to rotate the crowns 17 and 18 around the axes X _1X and X ₁₂ of the zones 11 and 12. The crowns 17 and 18 are provided, on their respective internal faces, with reliefs 17a and 18a. These reliefs are able to cooperate with corresponding reliefs 7b and 7'b provided on the rings 7a and 7 'has subassemblies 7 and 7'. Thus, the actuation of the jack 13 makes it possible to rotate the ring 7a of the subassembly 7 present in the zone 11 around the axis X ₁ and it is expected that this makes it possible to separate the subassembly 7 from the arm 6 of the robot 1. We are then in the position of FIG. 6 where the segment 6c of the arm 6 is lifted as represented by the arrow F ₃ , then moved in the direction of the zone 12 as represented by the arrow F ₄ , then lowered in the direction of the sub- set 7 'as shown by arrow F ₅ . It is then possible to maneuver the cylinder 13 again to impart to the crown 18 a rotational movement around the axis X ₃ as represented by the arrow F ₆ in FIG. 7 so that the ring 7 ′ a makes it possible to lock the sub-assembly 7 ′ on the segment 6 bras of the arm 6, the sub-assembly 7 ′ then being able to be used by the robot 1 to put on a new bodywork after leaving the station 10, as represented by the arrow F ₇ at the figure 8.

The upper faces 1a and 7′c of the subassemblies 7 and 7 ′ in fact constitute joint planes allowing the mounting of these subassemblies alternately on the arm 6 of the robot 1. In particular, orifices 7d and 7'd fluid passage are provided, as are electrical connectors 7e and 7'e and, in the central part, an orifice 7f_ or 7'f for passage of an operating rod of a piston 8a of the reservoir 8.

As is apparent from FIG. 4, when the subassembly 7 is received in the zone 11, and before the actuator 13 is maneuvered, a unit 21, movable radially with respect to the axis X _{11 #} is located at a distance d sufficient not to interfere with the movement of introduction of the sub-assembly 7 into the receptacle 11b. This unit 21 is then moved by a jack 22 as shown by the arrow F ₈ in FIG. 4, so that it is connected to a connection zone 7g of the subassembly 7, as shown in FIG. 5.

The unit 21 is connected to a coating product change block 23 by a flexible conduit 24. The unit 21 is also connected, by a flexible conduit 25 to a source of compressed air not shown and, by a conductor 26 , to an electronic control unit, also not shown. Thus, when it is connected to the area 7g of the subassembly 7 as shown in FIG. 5, the unit 21 allows supplying the reservoir 8 and the projector 9 with coating product, current and air. In particular, an air bearing formed in the headlight 9 can thus be supplied before the segment 6ç_ of the arm 6 is disconnected from the subassembly 7, so that this air bearing is permanently sufficiently "rigid" to maintain moving parts apart and thus avoid interference between them.

A second unit 27, similar to unit 21, is provided opposite zone 12.

Furthermore, the structure of the station 10 comprises a carriage 30 movable in a direction parallel to a plane containing the axes X _X1 and X ₁₂ . The carriage 30 is supported by rails 31 and 32 which are generally horizontal and carries a jack 33 able to move vertically, that is to say perpendicular to the direction of movement of the carriage 30, a plate 34 which itself supports a set of connection 35 comprising orifices 35d and connectors 35e provided to cooperate with the orifices 7d, 7d 'and the connectors 7e and 7e' of the subassemblies 7 and 7 '. In fact, the elements 35d and 35e are arranged in the same configuration as the corresponding elements in the segment 6c of the arm 6. The plate 35 also carries a jack 36 capable of actuating a rod 37 capable of penetrating into orifices 7f or 7 ' f of one of the subsets 7 and 7 '.

Thus, when the carriage 30 has been moved in the direction of the zone 11 as represented by the arrow F ₉ in FIG. 9 and when the plate 34 has been lowered as represented by the arrow F ₁₀ in this figure, the orifices 35d and the connectors 35e which are connected, by a bundle 38 of pipes and flexible cables received in an unwinder 39, to power supply assemblies not shown, make it possible to control the subassembly 7 in place of the robot 1. In particular, the rod 37 is able to penetrate into the subassembly 7 as shown in FIG. 11 so as to push the piston 8a of the reservoir 8 in order to purge the reservoir.

Tank 8 and projector 9 cleaning operations can take place according to a pre-established sequence in particular through the unit 21, the control of the operating parameters of the reservoir 8 and of the projector 9 can be carried out through the connection assembly 35, as when the sub-assembly 7 is mounted on the robot 1. For example , the speed of rotation of a turbine of the headlight 9 can be controlled by means of a tachometer.

The tank 8 is filled by the unit 21 because it is located as close as possible to the bottom of the tank 8 in the position of FIG. 11, which means that the internal conduits of the connection area 7g are short. The unit 21 also makes it possible to clean the headlight 9, by circulating therein a rinsing product, then to initiate it with the new coating product, by circulating in it a small amount of the new product of coating which is then poured into the bottom of the receptacle 11b and discharged through the conduit lie.

When these operations are completed, and as shown in FIG. 11, the connection assembly 35 is detached from the sub-assembly 7, the plate 34 is lifted as represented by the arrow F _X1 and the carriage 30 is brought back to a middle position between the zones 11 and 12 as represented by the arrow F ₁₂ , while the arm 6 of the robot 1 brings the subassembly 7 ′ towards the reception zone 12 as shown with the arrow F ₁₃ . In view of the above, the time available for cleaning and filling the reservoir 8 and the headlight 9 included in the sub-assembly 7 is less than or equal to the time of use of the sub-assembly 7 ′, ie approximately 1 mm in the case of an installation for spraying coating products on vehicle bodies during scrolling.

This time is much greater than the time usually available, so that these cleaning operations, filling the tank and starting the projector can be carried out with great care, while the change of sub-assembly as it is shown in Figures 6 and 7, is particularly fast, the production rates can be increased accordingly.

Claims

1. Method for changing a product in a coating product spraying installation comprising at least one robot (1), capable of moving a first projector (9) and a first reservoir (8) associated opposite objects to be coated

(3), said method comprising a step of bringing said first tank to a zone (11) adapted from a cleaning / filling station (10), characterized in that it consists in:

- Separating a sub-assembly (7) comprising said first tank (8) and said first projector (9) relative to said robot;

- securing with said robot, a second sub-assembly (7 ') similar comprising a second tank (8') and a second projector (9 '), said second sub-assembly being suitable for being used for the projection of coating product during the cleaning and / or filling of said first tank and of said first projector, and - cleaning and / or filling of said first tank and of said first projector in said zone (11).

2. Method according to claim 1, characterized in that it consists in supplying said first sub-assembly (7) with air, in cleaning product and / or in coating product, in said zone (11) before its separation from 'with said robot

(1) •

3. Method according to one of claims 1 or 2, characterized in that it consists in supplying said subassembly (7) with air, electric current, cleaning product and / or coating product, by means of two mobile units (21, 35), a first unit (21) being connected to said subassembly before its separation from said robot (1) and a second unit being connected to said subassembly after its separation from said robot robot, instead of the connection part (6ç_) of said robot.

4. Method according to one of the preceding claims, characterized in that it consists in permanently supplying said projector (9) with air forming a bearing between moving parts of the projector.

5. Product change station (10) in a coating product projection installation, said installation comprising at least one robot (1), capable of moving a projector (9) and a reservoir (8) associated opposite one another. objects to be coated (3), said station comprising at least two zones (11, 12) for cleaning and filling said tank (8), characterized in that said zones are each capable of receiving a sub-assembly (7, 7 ') formed of a reservoir (8, 8 ') and a projector (9, 9') while this sub-assembly is detached from said robot (1), means (21, 27, 35) being provided for cleaning and / or fill said tank and said sprayer in each of said zones.

6. Station according to claim 5, characterized in that said means comprise two mobile units (21, 27,

35) able to be independently connected in two connection zones of said sub-assembly (7), a first unit (21, 27) being able to be connected to said sub-assembly mounted on said robot (1) while a second unit (35) is able to be connected to said sub-assembly in place of the connection part (6ç_) of said robot.

7. Station according to claim 6, characterized in that said first unit (21, 27) comprises means of connection between a source of compressed air and a bearing formed in said projector (9) between two parts in relative movement.

8. Station according to one of claims 6 or 7, characterized in that said second unit (35) carries a jack (36) whose rod (37) is capable of operating a piston (8a) of said tank (8), especially for purging said tank.

9. Station according to one of claims 5 to 8, characterized in that it comprises means for locking a sub-assembly in each of said zones by rotation of a ring (17, 18) surrounding said sub-assembly (7, 7 ') and able to cooperate with reliefs (7b, 7'b) of said subassembly to drive said subassembly in rotation (F ₆ ) relative to said robot.

10. Station according to claim 9, characterized in that said ring (17, 18) is controlled in rotation, between a locking position and an unlocking position of said subassembly, by a jack (13).

moving parts of the projector.