DE102004046351A1 - Automatic spraying of automobile hollow zones, at interiors and chassis, uses a simulation of the geometry produced by computer assisted design for the spraying robot parameter in a production line - Google Patents

Abstract

The automatic spraying action to preserve an automobile interior and chassis (23) with a wax coating against corrosion, by a robot at an automobile production line, takes the geometry of the hollow zones (1',1") of the automobile which is shown as a simulation by computer assisted design (CAD) to simulate the spraying action using the spraying assembly parameter. The simulation gives the zone to be covered by the coating and the optimum spray jet (3') and the optimum spray head (8) position for the spraying opening (9), which delivers the jet sprays (12).

Description

The The invention relates to a method for automatic preservation the cavities a motor vehicle with the aid of a spray system according to the preamble of the claim 1.

in the Automotive construction is one of the most possible in cavity preservation extensive automation of the preservation process in the foreground. There a motor vehicle body has a plurality of cavities, This means the parallel use of several spray nozzles for conservation one considerable time savings.

A Device for automatic preservation of cavities is from the genre-forming DE ... (not yet published, official act 102004037311.6) known. There is a nozzle frame proposed, are attached to the plurality of spray nozzles, with which simultaneously several cavities, which are adjacent in an area of the vehicle body, can be coated.

The Procedural steps, which so far cost a lot of time, are the actual spraying preliminary preparatory steps for the design of the spray unit. For each To preserve the cavity of the body, a suitable spray nozzle must be selected and be designed so that with it the desired spray result can be achieved. This has been done manually until now by having a prototype of the one to conserve Body type is studied in advance. Here are the corresponding cavities Physically cut in the prototype. In the respective cavity the places to be preserved such as flanges or welds with Marked. In a further step, be manual the appropriate spray nozzles selected and to attach to their nozzle heads Outlet holes to achieve an ideal spray pattern iteratively determined by several tests. Then the look is manually the nozzle body and the connection of the spray nozzles determined in the prototype tests as well as if robots are used, the travel distance of the robot during the robot may be exceeded Preservation process determined. These preparatory steps require, in addition to the high material value for the prototypes examined, which are unusable by the cutting of the cavities, very a lot of expert knowledge and experience.

Of the Invention is based on the object, a method for preservation the cavities of a Motor vehicle to propose with the at an early date automates the parameters without extensive tests on real bodies the spray system can be determined.

The The object is achieved by the Characteristics of claim 1 solved. After that takes place before the execution the spraying process based on a computer-internal geometry (CAD) model of the Automobile, an automated, computer-aided simulation of the spraying process during which the parameters of the spray system be determined.

So can even before the implementation the actual spraying process the important geometry and process parameters of the spray system reliable and without damaging Tests on real bodies are determined. The simulation can already at a very early age Time in the vehicle development take place. This allows the Vehicle developer support as well as an early one Receive feedback about if and how the selected ones Application points in the cavities can be coated.

amendments in the structural design of the cavities are at this early date in contrast to the generic method, in which the tests are carried out shortly before the start of production, still possible. Further The number of iterations can be used to determine optimal process parameters be significantly reduced by the process.

Farther can by the method according to the invention through the pre-simulation, the optimum amount of conductive through each spray nozzle Waxes are determined so that the desired spray pattern results. This can the amount of wax used over the generic method be lowered.

Further are the design data underlying the simulation (CAD data) of the motor vehicle always up to date, in contrast to Tests with real prototypes, which may be an outdated series version of the motor vehicle.

advantageously, be through the simulation as a parameter of the spray system for each to be coated cavity depending on its geometry and location as well as the areas of the cavity to be coated both the optimal spray nozzle selected as also the optimal position to be attached to the spray head of the spray nozzle Outlet holes for set the wax. These are the most important parameters the spray system (Claim 2).

advantageously, will the spray nozzle during the Coating process performed by a robot. This procedure allows an extensive automation of the spraying process with the associated Cost and time advantages. It is advantageously by the Simulation for each cavity to be coated an optimal trajectory for the robot before and after insertion the spray nozzle in the Cavity determined. So can the benefits of digital simulation for smooth automation of the process without consuming Manual device can be used (claim 3).

Farther can while the simulation of the formation of the wax jet generated by the spray nozzle as well as the spray pattern created by him be visualized. This is how the designer and the production planner receive their services at an early age Timing an insight into the future coating process and recognize possible weaknesses or potential for improvement (Claim 4).

advantageously, is during the simulation the accessibility of the respective cavity for the Spray nozzle examined. Should a cavity prove difficult or impossible to access, can constructive changes are still made at the time of the simulation, what in the generic method not possible is (claim 5).

In an advantageous embodiment is due to the during The simulation generated coordinates for the trajectory of the robot carried out an off-line programming of the robot. So can be saved the time normally for a manual Programming the robot involved in the coating process would be required (claim 6).

Further Embodiments and advantages of the invention will become apparent from the description out.

In The drawings, the invention with reference to several embodiments explained in more detail.

there demonstrate:

1 a spray system for automated cavity preservation,

2 a schematic representation of a spray nozzle used for cavity preservation,

3 an overview of an embodiment of a simulation method and

4 an embodiment of a visualization of a cavity coating.

1 shows an embodiment of a spray system 14 as used for automated or semi-automated preservation of cavities 1 of motor vehicles 2 For example, in the mass production of motor vehicles 2 , is used. The spray system 14 includes funding 15 , Spray nozzles 3 , Control devices and means for supplying and storing coating material.

When cavity preservation is a motor vehicle 2 with the help of a conveyor 15 into a workspace 16 the spray system 14 transported. There is every single space provided for conservation cavity 1 of the motor vehicle 2 or the body 23 preserved by a spray nozzle 3 through an opening 17 in the cavity 1 is introduced. Through the spray nozzle 3 then coating material is passed in the form of wax, which consists of in a nozzle head 8th the spray nozzle 3 provided exit holes 9 emerges again and according to the arrangement of the exit holes 9 on an interior wall 5 of the cavity 1 reflected.

This Operation is hereinafter referred to as spraying.

The spray system 14 includes in this embodiment, in addition to the above-mentioned components and robots 10 for automatic cavity coating. Depending on the location and accessibility of the cavity 1 becomes the spray nozzle 3 then either, as in 1 shown with the help of a robot 10 handled or manually by a worker in the cavity 1 introduced. For reasons of saving time, several robots can also be used 10 used simultaneously, as in 1 using the example of two parallel robots 10 shown.

2 shows as an essential part of the spray system 14 an embodiment of a spray nozzle 3 , This includes the spray nozzle 3 a nozzle body 18 , at the end of which is a nozzle head 8th located. In the nozzle head 8th are the exit holes 9 through which the wax from the spray nozzle 3 exit. Between a nozzle base 19 which in the case of automatic application of the wax with the robot 10 is connected, and the nozzle body 18 there is a nozzle tube 20 , This nozzle tube 20 is made of a flexible material and can be designed by bending so that the area to be coated 7 of the respective cavity 1 is reached as well as possible, or the nozzle 3 in the intended opening 17 at the right angle into the cavity 1 can be introduced.

The design of a spray nozzle 3 depending on the cavity to be preserved 2 , which must take place before the spraying process, so in principle has the two degrees of freedom of the design of the nozzle head 8th and the nozzle tube 20 ,

As explained above, the design of the spray unit is decreasing 14 , which precedes the spraying in the cavity preservation, so far took a lot of time: For each cavity 1 or for each area to be coated 7 of the cavity 1 must have a matching spray nozzle 3 must be selected and designed, then when using robots 10 the connection of the spray nozzle 3 to a robot 10 and one from the robot 10 Traversing path to be covered during the procedure 11 be determined. Furthermore, the other process parameters of the spray system such as waxing and pressure must be set. So far, this has been done iteratively with the help of elaborate tests on real bodies 23 , where the bodies 23 must be partially destroyed during the experiments.

These problems are overcome by the method according to the invention with the aid of an upstream simulation. A schematic overview of a possible embodiment of the simulation method is in 3 shown.

The main component of the process is a digital simulation of the coating process, in the course of which the parameters for the spray system 14 be determined. This simulation takes place before the actual coating, ie at an early stage of the vehicle development process. The simulation has the in 3 displayed input variables 21 and output variables 22 ,

As input 21 serves on the one hand the exact specification of the cavity to be coated 1 , For this purpose, in this embodiment, on the one hand, the geometry and the position of the cavity 1 in terms of the body 23 and, on the other hand, the location of the area or areas to be coated 7 inside the cavity 1 needed. Location and geometry of the cavity 1 become from an already existing in digital form geometry model of the motor vehicle 2 taken. This model has been developed in the course of the previous vehicle development process as a CAD model and is always kept up to date with changes in the course of further development so that it reliably and up-to-date provides the required data. Based on this CAD data, the areas to be coated now become 7 of the cavity 1 established. These are, for example, corrosion-prone areas such as flanges, welds or areas in which the body panel is exposed to specific environmental pollution, for example by splashing. These areas are determined based on expertise and experience from other vehicle models.

Cavity preservation is done with the help of a robot 10 , must also be the geometry data of the robot or robots 10 in digital form as input variables 21 be available.

• – Auskonstruierte Sprühdüse 3, d.h. durch die Simulation findet die digitale Auslegung der gesamten Sprühdüse 3 mit der Festlegung der Düsengeometrie, der Lage und der Anzahl der am Düsenkopf 8 anzubringenden Austrittsbohrungen 9 sowie die Geometrie des Düsenrohrs 20 und gegebenenfalls dessen Anbindung an den Roboter 10,
• – die Festlegung des Sprühbildes 13, welches durch die Sprühdüse 3 erzeugt wird. Dieses Sprühbild 13 ist so optimiert, dass die zu beschichtenden Bereiche 7 gemäß den Vorgaben mit der entsprechenden Menge Wachs bedeckt sind, sowie
• – die Festlegung der Wachsmenge, d.h. der minimalen Menge an Wachsmaterial, welches durch die Sprühdüse 3 geleitet werden muss, so dass ein gutes Sprühbild 13 entsteht.

Are all input variables 21 consistent, the simulation and optimization begins. The aim of the simulation and optimization is primarily the generation of the output variables 22 drawn parameters of the spray unit 14 , In this embodiment, these are essentially the following three parameters:

• - Constructed spray nozzle 3 , ie through the simulation finds the digital design of the entire spray nozzle 3 determining the nozzle geometry, the location and the number of nozzles on the nozzle head 8th to be mounted exit holes 9 as well as the geometry of the nozzle tube 20 and optionally its connection to the robot 10 .
• - the definition of the spray pattern 13 passing through the spray nozzle 3 is produced. This spray picture 13 is optimized so that the areas to be coated 7 covered according to the specifications with the appropriate amount of wax, as well
• - The determination of the amount of wax, ie the minimum amount of wax material, which through the spray nozzle 3 must be directed, so that a good spray picture 13 arises.

The simulation also allows the other process parameters, such as the ideal spraying times for each spray nozzle 3 be determined.

If a robot is used, this results in a further output variable 22 In addition to the pure nozzle and wax parameters, the simulation also connects the spray nozzles 3 to the robots 10 as well as the trajectories 11 on which the robots 10 during handling of the nozzles 3 before and after insertion into the cavities 1 should ideally be moved. These are the ways of a storage position in which a spray nozzle 3 is in an opening when not in use 17 in the cavity 1 and back again or the path between two different cavities 1 , provided this with the same spray nozzle 3 be coated.

The simulation takes into account a number of external factors influencing the spray system 14 , which is used for the cavity preservation, are already given. These influencing factors include the specific parameters of the wax material used, the air pressure of the air flow, the pressure under which the wax passes through the spray nozzle is directed, the Lackskid, as well as the parameters for the transport of the body 23 used funds 15 like speed and cycle times.

In this embodiment, in addition to the determination of the output variables 22 based on the input variables 21 another part of the process in 3 as an additional result illustrated visualization of the spraying process. The vehicle body is visualized 23 with all cavities to be coated 1 , the spray system 14 with the robots used 10 and spray nozzles 3 as well as those of the spray nozzles 3 generated wax rays 12 ,

An example of a possible visualization is in 4 shown. The figure shows a detail of a body 23 , in this case an area of the subsoil, with two cavities to be preserved 1' and 1'' which have different geometries. The data for visualization are from a CAD model of the vehicle body 23 taken. Both cavities 1' . 1'' have openings 17 on, through which the spray nozzles 3 ' . 3 '' for coating the interior walls 5 ' respectively. 5 '' can be introduced. These openings 17 also have different geometries. In the case of the first cavity 1' it is a relatively large section 24 while the second cavity 1'' only a smaller hole 25 as an opening 17 Has. Furthermore, for visualization, the area to be coated must be 7 of the cavity 1 be known. This one is for the cavity 1' exemplified by a dashed highlighted flange 26 shown. Exemplary is in 4 a spray nozzle 3 ' shown in the cavity 1' is introduced. Their nozzle head 8th has three exit holes 9 on, and the course of through these exit holes 9 emerging wax rays 12 is visualized in the form of conical objects, their size and opening angle depending on the properties of the wax and the exit holes 9 is calculated. Furthermore, this is due to this wax jets 12 generated spray pattern 13 visualized. So can be visually assessed whether the spray pattern 13 the desired coating result for the flange 26 equivalent.

In this way, the user of this simulation method is easily and clearly possible, using virtual spray nozzle, robot and body models an overview of the parameters of the spray system 14 to win for the now following real spraying. Also the effects of changes in the process, such as the use of another spray nozzle 3 or another arrangement of the exit holes 9 are to be assessed directly in the simulation in this way. With this additional visualization expert knowledge is easily and clearly available even for non-specialists.

Of course, the method is not limited to automatic coating. Rather, it is also possible by the simulation, a design of the spray nozzles 3 for those cavities 1 perform which must be coated manually. In addition, the method also offers the possibility for each cavity 1 to investigate whether it is accessible to an automatic coating or not. Manually coated cavities 1 can be detected immediately.

Furthermore, by the simulation method for each cavity 1 its accessibility are studied at a very early stage. It can namely happen the case that a cavity 1 or its opening 17 is arranged so unfavorable that it is not possible, the areas to be coated 7 cover with wax of sufficient quality. In this case, since the simulation takes place early, feedback can be sent to the designers with the result that design changes, such as changes in the diameter or the position of the opening 17 up to a constructive transformation of the cavity 1 , at this stage can still be performed.

After the digital simulation of the coating process, the transition to the real coating process now takes place. The parameters for the spray system determined in the simulation 14 are converted into real components and process parameters, which can then be used directly for the real preservation process after a relatively short real test phase.

The Procedure is not limited to the presented embodiments.

Claims (6)

Method for the automatic preservation of cavities of a motor vehicle with the aid of a spray system, wherein a spray nozzle is introduced into a cavity to be preserved and sprayed onto the interior walls of the cavity by the spray nozzle, characterized in that before the spraying operation is carried out based on a computer-internal geometry (CAD) model of the motor vehicle ( 2 ) an automated, computer-aided simulation of the spraying process takes place during which the parameters of the spraying system ( 14 ) be determined. A method according to claim 1, characterized in that by the simulation as a parameter of the spray system ( 14 ) for each cavity to be coated ( 1 ) depending on its geometry and location as well as the areas to be coated ( 7 ) of the cavity ( 1 ) both the optimal spray nozzle ( 3 ) as well as the optimal position of the on a nozzle head ( 8th ) of the spray nozzle ( 3 ) exit bores ( 9 ) for the wax. A method according to claim 2, characterized in that by the simulation of a by a robot ( 10 ) guided spray nozzle ( 3 ) for each cavity to be coated ( 1 ) an optimal trajectory ( 11 ) for the robot ( 10 ) before and after insertion of the spray nozzle ( 3 ) in the cavity ( 1 ) is determined. Method according to one of claims 1 to 3, characterized in that during the simulation, the formation of the through the spray nozzle ( 3 ) produced wax beam ( 12 ) as well as the spray pattern ( 13 ) is visualized. Method according to one of claims 1 to 4, characterized in that during the simulation, the accessibility of the respective cavity ( 1 ) for the spray nozzle ( 3 ) is examined. Method according to one of claims 3 to 5, characterized in that due to the coordinates generated during the simulation for the trajectory ( 11 ) of the robot ( 10 ) an off-line programming of the robot ( 10 ) is carried out.