DE29715331U1 - System for the series production of body shells with body shell doors or flaps to be fastened thereon as well as body shell door or flap for fastening to a body shell - Google Patents

Description

PRINCE & PARTNERS

PATENT ATTORNEYS Manzingerweg 7

EUROPEANPATENTATTORNEYS D-81241 Munich

EUROPEAN TRADEMARK ATTORNEYS Tel. +49 89 89 69 80

Rennkamp Constructions GmbH
Senefelder Str. 17a,
86368 Gersthofen

Our reference: R 1483 DE G
AI/Gl
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Plant for the series production of body shells with
fastening shell doors or flaps and shell doors or
-flap for attachment to a body shell

The invention relates to a system for the series production of body shells with body shell doors and/or flaps to be attached thereto, with a first transport device for the body shells, a second transport device that conveys the body shell doors or flaps through various processing stations to an assembly station. The invention also relates to a body shell door or flap for attachment to a body shell, with an outer and an inner skin and a peripheral edge that, when mounted on the body shell, defines the gap visible from the outside to the body shell or to an adjacent door or flap.

To date, systems for manufacturing body shells and the doors and flaps to be attached to them have worked as follows: The body shell is produced with great technical effort so that its dimensions lie within tolerance ranges of 0.5 to 1 mm. The technical effort required to comply with these small tolerated deviations

is accepted because the doors and flaps to be installed later should have as small a gap as possible between the body and the vehicle when installed and visible from the outside. The gap widths that can be achieved so far are in the range of 3 to 5 mm. To achieve these gap widths, small tolerances must also be maintained during the manufacture of the doors and flaps. A great deal of effort is required, especially when flanging the sheet metal parts that form the inner and outer skin of the shell doors and flaps. Furthermore, the position of the hinge axis also determines the gap path, gap offset and the gap width, so that the position of the corresponding fastening points for the hinge must be closely tolerated. To ensure that the gap between the shell and the door or between adjacent doors is even, each door and each flap is aligned again relative to the shell during final assembly, which involves a great deal of effort.

The object of the invention is to create a cost-effective, technically simple system for the series production of body shells with doors and flaps for vehicles to be attached to them, which is also characterized by greater flexibility when changing models. In addition, the system should use known technologies and avoid disposable tools that are geared to the use of one type of vehicle. Furthermore, the invention should create a body shell door or flap that can be manufactured in a simple manner and that only creates a relatively narrow gap to the body shell or adjacent door or flap.

The task of creating a system is solved in a generic system in that it has at least one measuring station in which the door and/or flap cutouts of each incoming body shell are measured, which has at least one control unit in which, on the basis of the measured values obtained in the measuring station, a course of the peripheral edge of the door and/or flap to be manufactured specifically for the cutout can be calculated, which is tailored to each cutout, and which also has at least one cutting device controlled by the control unit, which trims the outer and/or inner skin of the corresponding door or flap to create the calculated course of the peripheral edge.

In the system according to the invention, the associated doors and flaps are tailored for each body shell by trimming the peripheral edge. The system according to the invention therefore offers the following advantages over previous systems:
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Extremely small gap widths and exact gap paths, which can also be predetermined, can be achieved.

Because the door or flap is adapted to the actual dimensions of the associated body shell anyway, the considerable technical effort required to maintain small tolerances in the body shell production of the body shell and the doors and flaps can be drastically reduced. This eliminates production fluctuations. The system according to the invention also makes it possible to make the device for trimming the peripheral edge flexible, i.e. easy to convert, e.g. by using a computer-controlled cutting device that can be adjusted to other model types and dimensions simply by reprogramming. The system according to the invention largely avoids the previously usual disposable tools. In particular, there is no provision for flanging the outer skin around the inner skin, so that the corresponding, very expensive flanging tool can be dispensed with, which previously involved a lot of effort in order to obtain doors and flaps that lie within small tolerances.

When measuring the body shell in the area of the cutouts, it may be sufficient to determine only individual points and calculate the course of the cutout between these individual points, which can speed up the measurement. According to one embodiment, the measuring station carries out an in-line laser measurement.

The measurement is preferably used to create a data set specific to the respective body shell, which is processed in a control unit. The control unit is used to determine the optimal course of the peripheral edge of the door or flap, taking into account the actual geometry of the cutout in the body shell. The control unit, which also consists of sub-units

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can control the subsequent processing of the peripheral edge in a cutting device.

Since the position of the pivot bearing(s) between the door or flap and the body, which are usually designed as a hinge connection, also has a strong influence on the position of the door or flap relative to the cutout and thus on the optimal course of the peripheral edge, the position of the pivot bearing is preferably used as a reference point when measuring the body shell and processing the peripheral edge. This is done by determining the position of the pivot bearings in a door or flap measuring station when they are already attached to the door or flap in the body shell state. The pivot bearing(s) can be firmly attached to the body shell, door or flap before assembly, e.g. by welding, and can be screwed to the corresponding opposite when the door or flap is assembled. Taking into account the calculated future position of the pivot bearing, the optimal course of the peripheral edge to be achieved is determined and the outer and/or inner skin on the peripheral edge is trimmed accordingly.

It is not absolutely necessary that all fastening openings are made before the peripheral edge is trimmed. Rather, it can be advantageous, after measuring the relevant cutout, to calculate the specific fastening points for the swivel bearing on the inner or outer skin or the body for the vehicle to be manufactured and to produce fastening openings at these fastening points in one station. The position of the fastening openings is therefore preferably only determined together with the trimming of the peripheral edge, so that more adjustment options are available when determining the optimal course of the peripheral edge.

In order to avoid rejects on shell doors due to excessive trimming, the untrimmed peripheral edge must of course be wider than the maximum tolerances of the door or flap cutout in the shell production. Preferably, the tolerances of the position of the pivot bearing must also be taken into account when determining the peripheral edge.

In the system according to the invention, the circumferential edge is preferably trimmed using a laser that is simply arranged in a 5-axis laser processing center and can traverse any geometry. This results in a high level of flexibility for the system that works with the method according to the invention. Alternatively, trimming can also be done using machining, e.g. using a high-speed milling cutter, which can also round off the circumferential edge in the same work step.

Preferably, the outer skin and the inner skin are joined after trimming the peripheral edge, to avoid tolerances, preferably in the same clamping in which the trimming is carried out. The joining can be carried out by gluing or welding in a joining station. The welding preferably takes place in the area of the peripheral edge, i.e. the outer and inner skin each have a peripheral edge in the area of which they lie against each other and thus form a common peripheral edge, which is also trimmed in the position of the outer and inner skin to be joined. This has the advantage that the outer and inner skin are no longer moved relative to each other between trimming and joining and have an outer edge that runs flush with each other after trimming. One embodiment provides that a laser welding device is provided for this purpose, which allows the angle of attack of the laser beam to be adjusted and the focus to be changed.

After joining, it is advantageous to round off the trimmed peripheral edge to avoid sharp cutting edges, which can be done by thermally or by machining the peripheral edge in a post-processing station, in the first case e.g. by means of a laser.

Joining and rounding can also be carried out in a common station, for example by using the laser welding mentioned above to create a round outer contour of the peripheral edge in cross-section. With the joining and rounding described, the previously usual adhesive application and the previously usual gelling station for sealing the flanged peripheral edge of the outer skin can also be omitted.

However, joining can also take place before trimming, so that doors and flaps are conveyed into the corresponding cutting device with the outer and inner skin locked together.

In the system according to the invention, the shell doors or shell flaps are manufactured after the shell body has been manufactured, so that gap widths of 1 mm can be easily achieved. The system can be converted to other model series very quickly, meaning that the entire system can be seen as a long-term investment that pays for itself within a few model cycles due to extremely low conversion costs.

The task of creating a shell door or flap, which is also stated in the introduction to the description, is solved in a shell door or flap of the type mentioned at the beginning in that the peripheral edge is defined by the outer or inner skin or by a flush lateral end of the outer and inner skin and the peripheral edge of the shell door or flap is trimmed in the area of the peripheral edge. In the previous doors or flaps, the peripheral edge is always defined by the outer skin that is beaded inwards. In the object according to the invention, however, a trim is provided on the peripheral edge, so that beading is no longer necessary. Although it is possible for the peripheral edge to be defined only by the outer or inner skin, depending on which of the two protrudes further outwards, the preferred embodiment provides that the inner and outer skin are flush and together define the peripheral edge. This results in greater stability in the area of the peripheral edge and a greater thickness of the door or flap in this area. Due to the greater thickness, cross-sectional contours can be achieved during rounding that exclude damage to the peripheral edge by avoiding sharp edges and borders.

Further features and advantages of the invention emerge from the following description and from the following drawings, to which reference is made. In the drawings:

Fig. 1 is a side view of a body shell manufactured in the plant according to the invention with attached body shell doors and flaps according to the invention, which are also manufactured in the plant according to the invention,
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Fig. 2 is a schematic plan view of a first embodiment of the system according to the invention,

Fig. 3 the body shell alone, where the cutouts for the front and rear doors are marked separately and measuring points for determining the geometry of the door cutouts are shown,

Fig. 4 a top view of a cutting device in the form of a 5-axis laser machining center, which is equipped with a CO2 laser as a cutting device,

Fig. 5 a cross-section through a not yet assembled shell door, which is trimmed by a laser at the peripheral edge,

Fig. 6a a cross-section through a joined and rounded shell door, which consists of a galvanized outer sheet and a galvanized inner sheet, in the area of the peripheral edge,

Fig. 6b is a view corresponding to Fig. 6a of a peripheral edge of a shell door having an inner and outer sheet made of aluminum,

Fig. 6c is a view corresponding to Fig. 6a, in which the inner and outer sheets are attached to each other by gluing, and

Fig. 7 is a plan view of a second embodiment of the system according to the invention.

In Fig. 1, a body shell 3 is shown on which numerous

Shell flaps and doors are attached, namely a trunk lid 5, a bonnet 7 as well as front doors 9 and rear doors 11. The criterion for a high quality of the shell is a gap 13 that is as narrow and consistent as possible between the outer

edges or peripheral edges 15 of the doors or flaps and the adjacent, associated cutout in the body shell into which the door or flap is inserted. In addition, a section of the gap 13, namely the gap at the B-pillar, is defined by the rear peripheral edge of the front door and the front peripheral edge of the rear door.

In the system outlined in Fig. 2, body shells with attached body shell doors and flaps can be manufactured, whereby gaps with a width of 1 mm can be achieved.

The system shown in Fig. 2 has a first transport device 17 for body shells and several second transport devices 19, of which only one is shown, for the doors and flaps, which are mounted on the body shell in a later assembly station 29. The transport device 17 works with so-called component carriers, on which the body shell parts or body shells are positioned in a fixed position and aligned with the component carrier. The individual component carriers are designated 21. The transport device 19 conveys clamping pallets 22, on which the outer skin and the inner skin made of sheet metal are already positioned relative to one another for the right front and right rear doors. The outer and inner skins lie against one another in the area of their peripheral edges 15, as will be explained later. 23 designates a 5-axis laser processing center, which is shown in more detail in Fig. 4. The corresponding laser, which is used to cut the peripheral edges 15 of the doors, is a CO2 laser, which has an output of approx. 2600 watts. The cutting speed of this machining center is approx. 5.6 m/min, so that with a length of the peripheral edge 15 of 3.5 m per door, the machining time is approx.

40 seconds is reached.

In the transport direction, a station 25 is arranged after the cutting device 23, which represents a combination of a post-processing station and a joining station.
35

On the side of the transport device 17 for the body shells, a measuring station 27 is provided in which the cutouts of each body shell are measured using known measuring devices by in-line laser measurement

-9-become,
into which the doors and flaps are installed.

In the assembly station 29, several robots 55 assemble the

supplied doors and flaps are attached to the body shell 3. A

Control unit 31 is connected to all stations and

controls the process flow.

In the measuring station 27, the geometries of all door and flap cutouts of all incoming body shells 3 are determined by inline laser measurement. The aim of the measurement is to determine the exact geometry of each cutout in the external area, which together with the peripheral edge of the door or flap that is later installed, which is visible from the outside, determines the gap that results between the door or flap and the body or between adjacent doors.

So that the entire contour of the cutout does not have to be traced, the body shell is scanned at individual points 33 (Fig. 3) and the course of the contour is determined to determine the overall geometry. In addition, the position of the fastening openings 35 is measured, by means of which the pivot bearings in the form of hinges already attached to the body shell door are later attached, e.g. screwed or pinned, in the assembly station 29. The fastening openings 35 serve as reference points for determining the geometry of the door and flap cutouts. A data set is created for each cutout either in the measuring station 27 or in the control unit 31. On the basis of this data set, the course of the peripheral edge of each door and flap is then calculated in the control unit 31, coordinated with the assigned cutout or with the immediately adjacent door, taking into account a predeterminable, very narrow gap 13 in the vehicle to be manufactured. When calculating the optimal outer circumference, the future position of the swivel bearings is also taken into account.

The corresponding data for the desired course of the outer circumference of each door and flap are forwarded from the control unit 31 to the cutting device 23. The control unit 31

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can also control the cutting device 23 or only supply the corresponding data to a separate control unit of the cutting device 23.

On each clamping pallet 22 that is moved into the cutting device 23, the outer skin 37 of the doors shown in Fig. 4 is pressed against the inner skin underneath by suitable positioning and clamping elements on the clamping pallet. In Fig. 4 it can be seen that the outer skin 37 and inner skin 39 lie against one another in the area of a peripheral edge 15, whereby the peripheral edge 15 is formed by the peripheral edges of the outer skin 37 and the inner skin 39. The width of the peripheral edge 15 in the not yet machined state is greater than the maximum tolerances of the door or flap cutout in the bodyshell production, taking into account the tolerances of the position of the pivot bearing(s), which are otherwise designated 43 in Fig. 4.

By providing a sufficient width of the peripheral edge 15 to be machined, the tolerances in the bodyshell production, which can be specified very generously, and tolerances of the door or flap itself are absorbed. The CO2 laser shown in Fig. 5 trims the peripheral edge 15 of each door and cuts its course to the geometry of the associated cutout.

Nitrogen is used as the cutting gas in the laser 45. As an alternative to the embodiment shown in Fig. 4, several cutting devices 23 can also be provided, which process doors or flaps positioned on individual clamping pallets 22. In the embodiment shown in Fig. 4, however, both the front door 9 and the rear door 11 are trimmed with a laser.

In the same clamping in which the circumferential edge 15 is trimmed, the circumferential edge 15 trimmed in this way is reworked in the downstream station 25. Furthermore, the outer and inner skin 37 and 39 are joined together, which is shown in Figures 6a to 6c. In order to obtain a rounded outer contour of the circumferential edge 15 in cross-section and to prevent moisture from penetrating between the outer and inner skin 37 and 39 via the circumferential edge 15,

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the outer and inner skin 37 and 39 are welded together and thus joined by a CO2 laser (not shown). The CO2 laser (not shown) is part of a multi-axis machining center, which can be constructed essentially in the same way as the cutting device 23.

The CO2 laser is aimed at the front, i.e. in the direction of the arrow, at the trimmed peripheral edge 15, whereby the angle of attack of the laser beam and the focus are adjustable. Furthermore, other parameters can also be changed so that an outwardly rounded contour of the weld seam 47 is achieved. In station 25, the outer skin 37 or 39 is joined to the inner skin and the peripheral edge 15 is rounded.

Since in the embodiment according to Fig. 6a two galvanized sheets are welded together, care must be taken to ensure that there is always a space 49 between the sheets for the zinc that evaporates during welding. For this purpose, impressions are provided at certain intervals on the inner skin 39, which result in projections 51 on the side facing the outer skin 37, which serve as spacers.

In the embodiment shown in Fig. 6b, two aluminum sheets are welded together as outer and inner skins 37 and 39, respectively, with no space 49 being provided between them.

As an alternative to the joining process described above, the outer skin 37 and the inner skin 39 can also be glued together, as shown in Fig. 6c. Instead of station 25, several stations are provided for this purpose, namely, as shown in Fig. 7, a joining station 61 in which adhesive is applied, and a post-processing station 63 in which the peripheral edge trimmed in the cutting device 23 arranged between them is rounded. This rounding can be carried out, for example, by a solid-state laser, which produces the weld seam 47 and, together with the adhesive 53, serves to fasten the sheets and the seal. It is also possible to arrange the joining station after the cutting device 23. In this case, however, the outer skin must be lifted off the inner skin in order to apply the adhesive and then repositioned in the exact position after the adhesive has been applied.

Furthermore, between the measuring station 27 and the assembly station 29 and/or between the cutting device 23 and the assembly

station 29, a further processing station can be provided in which fastening openings on the body shell 3 and on the body shell door or flap for the pivot bearings 47 are created with precision, which is done, for example, by a laser. This creation of fastening openings can also be done by the cutting device 23, depending on when and to which part the pivot bearings 43 are to be attached first.

The precisely dimensioned door or flap, which is manufactured in just a few minutes, is then fixed to the body shell 3 in the assembly station 29, e.g. by screwing it on, with robots 55 also aligning the doors and flaps. The body shell thus completed is then transferred to the paint shop.

It is also conceivable to combine the cutting device 23 and the station 25 according to Fig. 2 into one station in which, immediately after the circumferential edge 15 has been trimmed, a rounding is carried out by a trailing laser with simultaneous joining. It is also advantageous in the system shown in Fig. 7 to combine the cutting device 23 and the post-processing station 63 into one station by for example, trimming and rounding the circumferential edge 15 with a high-speed milling cutter.

The system shown, which works with the method described above, is characterized by a high degree of flexibility, since all stations can be quickly converted to other models without a long downtime, which can mainly be done by reprogramming the control unit 31. This results in even reduced production costs over several model generations with a higher quality than has been achieved so far.

For replacing doors or flaps, e.g. after an accident,

Very simple measuring gauges are provided in the repair shops, with which the cutout to be fitted with the new door or flap is measured at a few points. These points are then sent to the car manufacturer.

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The entire course is determined on the basis of the individual specified points and a precisely dimensioned door is manufactured. This also shows the advantage of the invention: small deviations from the standard dimensions are tolerable when repairing the body, since the door or flap does not have standard dimensions, but is adapted to the repaired body.

Claims (26)

PRINCE & PARTNERS PATENT ATTORNEYS Manzingerweg 7 european patent attorneys D-81241 Munich EUROPEAN TRADEMARK ATTORNEYS Tel. +49 89 89 69 80 Rennkamp Constructions GmbH
Senefelder Str. 17a,
86368 Gersthofen Our reference: R 1483 DE G
AI/Ge Protection claims 1. System for the series production of body shells (3) with body shell doors (9, 11) and/or flaps (5, 7) to be attached thereto, with a first transport device (17) for the body shells (3), a second transport device (19) which conveys the doors (9, 11) or flaps (5, 7) through various processing stations to an assembly station (29), characterized by at least one measuring station (27) in which the door and/or hatch openings of each arriving body shell (3) are measured, at least one control unit (31) in which, on the basis of the the measured values obtained from the measuring station (27) can be used to calculate a profile of the peripheral edge (15) of the door (9, 11) or flap (5, 7) to be manufactured specifically for each cutout, and a cutting device (23) controlled by the control unit (31) which trims the outer and/or inner skin (37, 39) of the corresponding door (9, 11) or flap (5, 7) to create the calculated course of the peripheral edge (15). 2. System according to claim 1, characterized in that the first transport device (17) conveys the body shell (3) into the measuring station (27) and from there to an assembly station (29) in which the -2- assigned door (9, 11) or flap (5, 7) specially manufactured to the dimensions of the assigned cutout is mounted on the body shell (3). 3. Installation according to claim 1 or 2, characterized in that the measuring station (27) can carry out an in-line laser measurement. 4. Installation according to one of claims 1 to 3, characterized in that the cutting device (23) is a multi-axis machining center. 5. System according to one of claims 1 to 4, characterized in that the cutting device (23) carries out a machining operation. 6. System according to claim 4, characterized in that the cutting device (23) has at least one cutting laser (45). 7. System according to claims 4 and 6, characterized in that the cutting device (23) is a 5-axis laser machining center. 8. System according to one of claims 1 to 7, characterized in that the cutting device (23) is followed by a joining station in which the outer and inner skin (37, 39) are fastened to one another. 9. System according to one of claims 1 to 7, characterized in that a joining station is provided in front of the cutting device (23), in which the outer and inner skin (37, 39) are fastened to one another. 10. System according to claim 8 or 9, characterized in that the joining station is a bonding station in which the outer and inner skin (37, 39) are bonded together. 11. System according to claim 8 or 9, characterized in that a post-processing station is provided after the cutting device (23) or the joining station, in which the trimmed peripheral edge (15) is rounded. -3- 12. System according to claims 9 and 11, characterized in that the cutting device (23) also carries out the rounding. 13. System according to claims 8 and 10, characterized in that the post-processing station and the joining station are a common station in which a welding device welds the outer and inner skin together at the peripheral edge. 14. System according to claim 8, characterized in that the joining station has a welding device (23) which welds the outer and inner skin (37, 39) together at the peripheral edge (15). 15. System according to claim 14, characterized in that the welding device is a laser welding device, wherein the angle of attack of the laser beam and the focusing are adjustable. 16. Plant according to claim 15, characterized in that the laser welding device is a CO2 laser welding device. 17. Installation according to one of claims 13 to 16, characterized in that the cutting device is part of the common station. 18. System according to claim 11, characterized in that the post-processing station is provided after the joining station and a laser is provided for rounding the trimmed peripheral edge. 19. System according to claim 18, characterized in that the laser for rounding is a solid-state laser. 20. System according to one of the preceding claims, characterized in that a door or flap measuring station is provided in which the position of the pivot bearings (43) attached to the door or flap or the corresponding attachment points is determined. -4- 21. System according to one of the preceding claims, characterized in that a station for producing openings for the attachment of the pivot bearings (43) to the shell door, shell flap or shell body is provided. 22. Shell door or flap for fastening to a shell body, with an outer and an inner skin (37, 39) and a peripheral edge (15) which, when mounted on the shell body (3), defines the gap (13) visible from the outside to the shell body (3) or to an adjacent door (9, 11) or flap (5, 7), characterized in that the peripheral edge is defined by the outer or inner skin or by a flush lateral termination of the outer and inner skin (37, 39) and that the peripheral edge of the shell door or flap is trimmed. 23. Shell door or flap according to claim 22, characterized in that the outer and inner skin (37, 39) are connected to one another in the region of the peripheral edge (15). 24. Shell door or flap according to claim 23, characterized in that the outer and inner skin (37, 39) are connected to one another by gluing or welding. 25. Shell door or flap according to one of claims 21 to 24, characterized in that the peripheral edge (15) is rounded. 26. Shell door or flap according to claim 25, characterized in that the rounding is achieved by means of a circumferential weld seam (47).