WO2016206787A1

WO2016206787A1 - Folding device

Info

Publication number: WO2016206787A1
Application number: PCT/EP2016/001018
Authority: WO
Inventors: Ralf Vollnhals; Oliver Luxenburger; Anton Habermeier
Original assignee: Audi Ag
Priority date: 2015-06-22
Filing date: 2016-06-16
Publication date: 2016-12-29
Also published as: DE102015007966A1; DE102015007966B4

Abstract

The invention relates to a folding device for folding sheet metal parts (3, 5) lying on a folding bed (11) by means of a folding unit, which has at least a preliminary and/or final folding segment (8, 16) and a control unit (45), by means of which a folding force (F_F) can be applied to the folding bed (11) and/or the preliminary and/or final folding segment (8, 16) in the folding process in such a way that a folding joint extending over a folding length (l_F) is formed between the two sheet metal parts (3, 5). According to the invention, an evaluating unit (43) having pressure sensor elements (33, 35, 37, 39) is provided in order to sense a folding force distribution (F_F(l)) over the folding length (l_F), which pressure sensor elements are spaced apart from each other along the folding length (l_F) and are arranged in a force flow path between the folding bed (11) and the folding unit.

Description

folding device

The invention relates to a folding device according to the preamble of

Claim 1.

In vehicle bodywork sheet metal parts can be joined by means of a rabbet joint. By way of example, the overlapping peripheral edges of sheet metal parts, for example an inner sheet metal part and an outer sheet metal part of a vehicle door, can be joined together in a seaming process to form a seam joint running around the vehicle door outer periphery.

From DE 10 2006 009 292 A1 discloses a generic folding device is known in which lying on a folding bed sheet metal parts are joined together by means of a folding unit. The folding unit has a prefolding segment and a finished folding segment. With the prefold segment, an edge web of the first sheet metal part can be prefolded around the sheet edge of the second sheet metal part. Subsequently, by means of the Fertigfalzsegmentes the already bent edge web of the first sheet metal part can be fertiggefalzt in fixed abutment with the sheet edge of the second sheet metal part. For this purpose, the Fertigfalzsegment is acted upon with a predetermined folding force.

For a qualitatively perfect seam connection it is necessary that the folding force applied to the sheet metal parts is sufficiently large. If the folding force is too low, this does not result in a perfect seam connection, as a result of which the folded sheet metal part arrangement has to be fed to a broke.

CONFIRMATION COPY In the large-scale production of, for example, vehicle doors, the sheet metal parts to be joined together of a sheet metal batch can have slight fluctuations in the sheet thickness due to tolerances. With regard to process reliability, therefore, the sheet metal parts to be folded in the

Folding process with a greatly increased folding force (i.e., under high

Energy expenditure) folded to any sheet thickness tolerances

compensate. Accordingly, the drive unit of the folding segment must be operated in the folding process with an excessively large electrical power consumption in order to generate the excessive folding force.

From DE 10 2012 022 332 A1 a folding device is known, which has an evaluation unit, by means of which a material failure at folding edges can be detected. From WO 2013/149894 A1 is a robot-controlled

Folding tool known to which an evaluation unit is assigned, by means of the compensation of robot elasticities a pressing force can be nachsteuerbar during the folding process.

The object of the invention is a folding device

to provide, in which the process reliability is increased in a simple manner and / or in the simple manner, the energy consumption in the folding force generation in the folding process is reduced.

The object of the invention is solved by the features of claim 1. Preferred developments of the invention are in the

Subclaims disclosed.

The invention is based on the fact that in the prior art, the folding bed and / or the Vor- / Fertigfalzsegment are linearly delivered by means of a feed motor on a folding stroke, without precise knowledge of the resulting folding force distribution in the folding process on the Folding length acts on the sheet metal parts to be joined and varies depending on sheet thickness tolerances. Against this background, according to the characterizing part of claim 1 for detecting a

Falzkraftverteilung an evaluation provided with pressure sensor elements. The pressure sensing elements are spaced apart along the folding length and disposed in a folding force path between the folding bed and the folding unit.

The invention may preferably be realized in a folding device (folding machine) which has both a prefolding segment and a finished folding segment, which are each subdivided into individual folding jaws. In a first Vorfalzhub an upward protruding, before the beginning of

Folding by, for example, 90 ° angled edge web of the first sheet metal part by the prefolding segment to the sheet edge of the second

Sheet metal part pre-folded. This is followed by a Fertigfalzhub, in which the

Fertigfalzsegment with a folding force presses the pre-folded edge web of the first sheet metal part in rabbet connection with the second sheet metal part, whereby the sheet edge of the second sheet metal part is completely covered by the fold of the first sheet metal part.

As already mentioned above, it is necessary for a perfect seam connection that the seaming segment acts on the sheet metal parts at least with a predetermined folding force. The folding force is by appropriate control of the actuator to a feed electric motor

Fold segment generated. For monitoring and / or readjustment of the folding force generated there, at least one folding force threshold value can be stored in the evaluation unit. In the folding process, the folding force threshold value is compared with the detected folding force distribution. If the detected

Falzkraftverteilung is at least partially smaller than the folding force threshold, the evaluation unit generates a signal on the basis of which on the Sheet metal parts acting folding force is increased until the folding force distribution, consistently over the entire folding length, above the folding force threshold. Preferably, the monitoring and / or optionally readjustment of the folding force can take place in a fully automatic readjustment process. In this case, the evaluation unit can be integrated in a control loop in which the evaluation unit is in signal connection with the folding segment setting unit. By means of the control loop, the size of the folding force acting on the sheet metal parts in the folding process in dependence on the detected, distributed over the folding length Falzkraftverteilung is automatically adjustable.

In a technical embodiment, in the control loop that of the

Evaluation unit generated signal as a control signal for controlling the

Folding segment actuator can be used. In the presence of the actuating signal, the folding force is increased by means of the adjusting unit. In NichtVorliegen the

Actuator signal, however, remain unchanged by the actuator folding force generated during the folding process. The invention is both in a Einrichtprozess as well as in a

Series process applicable. The setup process is before the start of the

Serial production can be carried out in a spotting or testing folder press. Here, a toolmaker in a simple way by optical

Evaluation of the detected folding force distribution rework the folding segments manually to achieve the most constant folding force distribution above the folding force threshold. In the series process, on the other hand, in a fully automatic readjustment process, the folding force acting on the sheet metal parts can be increased until reaching the folding force threshold value. Overall, with the invention, a perfect folding quality and a Reduction of rejects achieved in comparison to the prior art accelerated.

In a technical implementation, the folding unit can at least one

Have fold segment with a support frame. Mounted on the support frame are a number of folding jaws spaced along the folding length. In the folding process, the folding jaws act with the interposition of a common, flat shaped body on the sheet metal parts to be folded. Preferably, each of the folding jaws can be mounted with the interposition of a pressure sensor element on the support frame. In this way, the partial folding force acting on each folding jaw in the folding process can be detected. The entirety of the partial folding forces forms folding force distribution.

To further increase the process reliability (that is to the other

Reduction of rejects), the folding jaws under

Intermediate circuit of a floating rocker element to be mounted on the support frame of the folding unit. The rocker element can be articulated in a technical realization about a tilt axis pivotally mounted on the support frame. In the folding process can thus under tilting movement of the

Rocker element a sheet thickness tolerance in the sheet metal parts to be folded are compensated. The sheet thickness tolerance can be in one

Magnitude of, for example, 5/100 mm, so that even a very small compensation movement of the folding jaws in a range of a 1/10 mm is sufficient,

The above-explained and / or in the subclaims

reproduced advantageous embodiments and / or developments of the invention may - except, for example, in the case of clear dependencies or incompatible alternatives - individually or in any

Combination with each other are used. The invention and its advantageous embodiments and further developments and advantages thereof are explained in more detail below with reference to drawings.

Show it:

Figs. 1 and 2 are schematic diagrams, the one with a folding machine

illustrate feasible folding process;

Fig. 3 shows a detail of a folding machine with a

Fertigfalzsegment and a folding bed;

4 is a diagram showing a folding force distribution resulting during the folding process; and Fig. 5 is a view corresponding to Fig. 2 according to a second

Embodiment.

1 and 2 is for simplifying the understanding of the invention, first roughly schematically illustrates a sequence of work in a folding machine during the folding process, in which the workpiece to be folded 1 is a vehicle door, which is composed of an inner sheet metal part 3 and an outer sheet metal part 5 , In Fig. 1, the two loose on one

Fold bed 7 lying sheet metal parts 3, 5 fixed by means of a hold-7.

Subsequently, a Vorfalzhub A, in which an upwardly projecting and bent before the start of Vorfalzhubes by 90 ° relative to the inner sheet metal part 3 fold web 9 by a einschwenkendes

Vorfalzsegment 8 is bent. This is followed by a Fertigfalzhub B (Fig. 2), in which the prefolded sheet metal parts 3, 5 are pressed with a hold-down 13 against the folding bed 11. In Fertigfalzhub B the folding bed 11 by means of a feed motor 15 (Fig. 2) with a predefined folding force F _F and with the interposition of the sheet metal parts 3, 5 to be joined against a stationary held Fertigfalzsegment 16 delivered. In Fertigfalzhub B of pre-folded fold web 9 of the outer sheet metal part 5 is pressed against the inner sheet metal part 3, namely to form a folded length over a fold length IF (Fig. 2) elongated hinge connection between the two sheet metal parts 3, 5th

2, the basic structure of the Fertigfalzsegmentes 16 is illustrated. Consequently, the Fertigfalzsegment 16 a

Supporting frame 19, which in FIG. 2 is an example of an angle profile with an upper horizontal support leg 21 and a vertical support leg 23 angled therefrom. On the support frame 19 of the Fertigfalzsegmentes 16 a total of four, along the folding length l _F spaced from each other folding jaws 25 are mounted. The folding jaws 25 act with the interposition of a common flat shaped body 27 on the sheet metal parts 3, 5 to be folded. In FIG. 2, the sheet-like molding 27 is shown spaced from the lower folding bed 11 by a tool gap 29.

The four folding jaws 25 are not mounted directly in Fig. 2 on the support frame 19 of the folding unit, but with the interposition of a

Rocker element 31, which is hinged about a tilting axis K slightly pivotable on the vertical support leg 23 of the support frame 19. During the folding process can by a compensating movement of the rocker element 31, a sheet thickness tolerance in the sheet metal parts to be folded 3, 5

be compensated.

The folding jaws 25 are each with the interposition of a

Pressure sensor element 33, 35, 37, 39 and with the interposition of shell plates 41 mounted on the rocker element 31, with the help of additional component or sheet thickness tolerances are compensated. The

Pressure sensor elements 33 to 39 are in Fig. 2 in signal communication with an evaluation unit 43. During the folding process the capture

Pressure sensor elements 33 to 39 acting on the individual folding jaws 25 Teilfalzkräfte Fi, F ₂ , F ₃ , F ₄ , from which the evaluation unit 43 determines a folding force distribution F _F (I) on the folding length IF. Such

Folding force distribution F _F (I) is exemplary in the later described

Diagram of Fig. 3 shown.

The evaluation unit 43 is in FIG. 2 part of a control loop R, in which the evaluation unit 43 is in signal communication with an actuating unit 45. By means of the adjusting unit 45 is in the folding process of the feed motor 15 of the

Folding bed 1 1 controllable. With appropriate control the folding bed 1 1 in Fertigfalzhub B with the folding force F _F against the stationary held Fertigfalzsegment 16 is deliverable. With the help of the control loop R, the folding force F _F acting on the folding bed 1 1 can be readjusted fully automatically during a folding operation, specifically as a function of the value detected by the evaluation unit 43

Folding force distribution F _F (I). For example, the Falzkraftverteilungskurve shown in the diagram of Fig. 3 with a solid line F _F (I), which is defined by the sensor-detected Teilfalzkräfte F- _\ ₄ to F obtained during the folding process in Fertigfalzhub B.

In the diagram of FIG. 3, the partial folding force Fi lies in the fold force distribution curve F _F (I) shown in a solid line below one in FIG

Evaluation unit 43 stored folding force threshold value F _s , which should not be fallen below for a perfect hinge connection. To increase the Teilfalzkraft F-ι the evaluation unit 43 generates a control signal S, on the basis of which the setting unit 45 a folding force specification for the

Feed motor 15 of the folding bed 1 1 increases, and while until the

Partial folding force Fi is above the folding force threshold value F _s . These Operating situation is illustrated in Fig. 3 by the dotted force distribution curve F _F (I) shown in dotted lines in Fig. 3, which results after the Fälzkraft- increase. The dotted force distribution curve FF (I) shown in dotted lines lies continuously over the entire folding length IF, above the folding force threshold value Fs, so that a perfect hinge connection is ensured.

4, a second embodiment is shown in the

Essentially identically constructed as that shown in FIG

Embodiment. In contrast to FIG. 2 in Fig. 4 is the

Evaluation unit 43 is not involved in a closed loop R, so that no fully automatic adjustment of the folding force F _F is made possible during the folding process. Instead, the in the

Evaluation unit 43 detected Falzkraftverteilung F _F (I), for example, during a Einrichtprozesses be evaluated by the toolmaker optically and on the basis of which optionally using

Schimsplatten 41 the folding force distribution F _F (I) can be influenced.

Claims

claims

Folding device for folding on a folding bed (1 1) lying sheet metal parts (3, 5) by means of a folding unit, which has at least one pre and / or Fertigfalzsegment (8, 16) and an adjusting unit (45) by means of the folding bed (1 1) and / or the pros and / or

Fertigfalzsegment (8, 16) in the folding process with a folding force (F _F ) can be acted upon, to form an over a fold length (l _F ) elongated hinge connection between the two sheet metal parts (3, 5), characterized in that for detecting a

Falzkraftverteilung (F _F (I)) over the folding length (l _F ) an evaluation unit (43) with pressure sensor elements (33, 35, 37, 39) is provided, which are spaced along the fold length (IF) and in a folding force path between the Fold bed (11) and the folding unit are arranged.

Folding device according to claim 1, characterized in that in the evaluation unit (43) a folding force threshold (F _s ) can be stored, and that in the folding process of the folding force threshold (F _s ) with the

Falzkraftverteilung (F _F (I)) is comparable, and that means of

Evaluation unit (43) is a signal (S) can be generated if the detected folding force distribution (F _F (I)) is at least partially smaller than the folding force threshold (F _s ).

Folding device according to claim 1 or 2, characterized in that the evaluation unit (43) in a control loop (R) is integrated, in which the evaluation unit (43) in signal communication with the

Actuator (45) is, and that by means of the control loop (R)

in particular the size of the sheet metal parts in the folding process (3, 5) acting folding force (F _F ) depending on the detected

Force distribution (FF (IF)) is adjustable.

Folding device according to claim 3, characterized in that the evaluation unit (43) generated signal (S) is a control signal for controlling the actuating unit (45), and that in the presence of the actuating signal (S), the folding force (F _F ) by means of the adjusting unit (45) can be increased.

Folding device according to Claim 4, characterized in that the evaluation unit (43) generates the actuating signal (S) until the force distribution (F _F (I)), throughout the entire folding length (I _F ), above the folding force threshold value (F _s ) is located.

Folding device according to one of the preceding claims, characterized in that the folding unit has at least one Fertigfalzsegment (16) with a support frame (19) on which a number of along the fold length (IF) spaced Falzbacken (25) is mounted, and that the Falzbacken (25) with the interposition of a common shaped body (27) on the sheet metal parts (3, 5) act.

Folding device according to claim 6, characterized in that each of the folding jaws (25) with the interposition of a

Pressure sensor element (33, 35, 37, 39) on the support frame (19) is mounted, with which in the folding process on the respective folding jaws (25) acting Teilfalzkraft (Fi, F ₂ , F ₃ , F ₄ ) is detectable, and that the

Entity of Teilfalzkräfte (Fi, F ₂ , F ₃ , F ₄ ) forms the folding force distribution (FF (IF)). Folding device according to claim 6 or 7, characterized in that the folding jaws (25) with the interposition of a tilting axis (K) pivotable rocker element (31) is mounted on the support frame (19) of the folding unit, and that in the folding process any sheet thickness tolerance in the sheet metal parts (3, 5) by a

Tilting movement of the rocker element (31) is compensated.