DE20105676U1 - System for treating, in particular for painting, objects, in particular vehicle bodies - Google Patents

Description

PATENT ATTORNEYS
DR. ULRICH OSTERTAG DR. REINHARD OSTERTAG

HBENWEG 10 D-70597 STUTTGAHT TEL.+49-71 1-766845 FAX+49-711-7655701

Plant for treating, in particular painting, objects, in particular vehicle bodies

Applicant:

Eisenmann Maschinenbau KG (General partner: Eisenmann Foundation) Tübinger Straße 81
71032 Boeblingen

Attorney file:

7558.. 1

AUN.253-180

·

7461.3

26.01.2001

Plant for treating, in particular painting, objects, in particular vehicle bodies

The invention relates to a system for treating, in particular for painting, objects, in particular vehicle bodies, with

(a) at least one bath containing a treatment liquid, in particular a varnish, in which the objects are to be immersed,

b) a conveyor device with which the objects can be guided through the system in a continuous or intermittent translational movement;

(c) a variety of immersion devices based on

a support structure connected to the conveyor via a connecting structure each carrying an object and being able to immerse this object in the bath.
25

Such a system is described in DE 196 41 048 C2. In this system, the immersion devices are designed in such a way that the objects to be treated, in the example shown, vehicle bodies to be painted, are immersed in the baths and then lifted out again by superimposing the translational movement and a rotational movement about an axis aligned perpendicular to the direction of transport. The connecting structures of these immersion devices are rigid holding frames in which, in the normal position,

AUN.253-088

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lower, middle area there is a single axis of rotation for the rotary movement. The purpose of this arrangement is to be able to completely immerse the objects to be treated in the baths over a relatively short path of translational movement, so that the front walls of the baths can be steep and the baths can be short overall. The disadvantage is that the objects to be treated have to be completely turned "upside down". For objects that are very heavy, this requires very complex support frames and great forces. If the objects to be treated are vehicle bodies, their moving parts, for example doors, trunks and engine hoods, have to be secured against opening. In addition, these known immersion devices only allow a single kinematics of the immersion movement, namely the rotary movement, which is not optimal for many objects that have unfavorable geometries for this.

The object of the present invention is to develop a system of the type mentioned at the beginning in such a way that, by using baths of essentially the same length, a rotation of the objects to be treated by 18 0° is not necessary and the kinematics of the immersion process

ganges can be made more variable if necessary.

This object is achieved according to the invention in that

d) the connecting structure comprises at least one pivot arm which is pivotably connected to the conveyor device about a first axis, and a drive device associated with the pivot arm, with which the pivot arm can be pivoted;

5 e) the supporting structure around a second axis which

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distance from the first axis, is pivotably connected to the swivel arm and

f) a drive device is provided with which the support structure can be pivoted about the second axis relative to the pivot arm.

According to the invention, a double pivoting option is provided within the connecting structure that each immersion device has: firstly, the pivot arm itself pivots relative to the conveyor device, and secondly, the support structure pivots relative to the pivot arm. Both pivoting movements can be effected independently of one another by a separate drive device. By coordinating the two drive devices accordingly, it is also possible to ensure that the object retains its orientation relative to the horizontal or vertical when the pivot arm pivots. The system according to the invention achieves particular flexibility when the two pivoting degrees of freedom are coupled with a suitable linear movement of the conveyor system.

It is advisable to arrange the drive device for pivoting the support structure relative to the pivot arm at a point that does not dip into the bath when the pivot arm is pivoted, and to connect it to the support structure via a mechanical adjustment device. The treatment fluids 0 within the baths, including paints, can be so aggressive that the drive device should not be exposed to these treatment fluids. The adjustment devices, on the other hand, can be designed to be so insensitive that they are not damaged by the treatment fluid.

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In this respect, it is particularly preferred that the adjustment device has a rod. Not only can considerable forces be transmitted via such a rod, it also works robustly and insensitively in an environment in which substances can deposit on it. Solidified deposits can be easily blasted off by such a rod.

It is particularly advantageous if the adjustment device comprises two rods which are hinged on one side to a part rigidly connected to the support structure and on the other side to a part rigidly connected to the output shaft of the drive device in such a way that they never reach a dead center at the same time. In this way, swivel angles greater than 18 0° can be easily generated.

In principle, however, the mechanical adjustment device 0 can also comprise a conventional chain.

An advantageous embodiment of the invention is characterized in that the output shaft of the drive device of the swivel arm is hollow and the output shaft of the drive device for swiveling the support structure is guided coaxially through the output shaft of the drive device of the swivel arm. This design is particularly space-saving.

0 The swivel arm conveniently carries a counterweight so that the torque required to swivel the swivel arm can be kept very small.

5 A similar aim is pursued in the design of the invention

7461.3 - 5 - 26.01.2001

in which the swivel arm interacts with an energy storage device which is able to temporarily store the energy released during the downward movement of the end of the swivel arm connected to the supporting structure in order to return it again during the upward movement.

An embodiment of the invention is explained in more detail below with reference to the drawing; 10

Figure 1: a perspective section of a dip-coating system for vehicle bodies;

Figure 2: a section through the system of Figure 1 perpendicular to the direction of movement of the vehicle

bodies, seen from bottom left;

Figure 3: a side view of the detail of the painting system from Figure 1;
20

Figure 4: a side view of a transport trolley used in the painting plant with a vehicle body attached thereto in the normal transport position;
25

Figure 5: a side view of the transport vehicle similar to Figure 4, but in which the vehicle body is pivoted 0 from the transport position for immersion in a bath or emergence from the bath;

Figure 6 : the top view of the trolley of Figure 5;

Figure 7: a perspective view of the trolley

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including vehicle body of Figure 4;

Figure 8: a section through Figure 6 according to the

Line VIII - VIII;
05

Figure 9: an enlarged detailed view in the area

of the one marked with the letter A

circle of Figure 2;

Figure 10: an enlarged detailed view in the area of the circle marked with the letter B in Figure 2.

The dip-painting system for vehicle bodies shown in the drawing comprises a steel structure 1 with a number of vertical stands and horizontal supports in which a bath tank 2 is suspended. The bath tank 2 is filled to a certain level with liquid paint into which vehicle bodies 4 are to be dipped. For this purpose, these vehicle bodies 4 are transported with the aid of individual transport carriages 5 in the direction of arrow 6 (see Figure 1), whereby this translational movement of the individual transport carriages 5 can take place independently of one another and during these independent movements, decelerations, accelerations, stops and also reversals of movement are possible. Overall, however, the vehicle bodies 4 are transported in the direction of arrow 6 in Figure 1.

The exact design of the transport carriages 5 is shown in more detail in Figures 4 to 10. As shown in particular in Figures 6 and 7, each transport carriage 5 has two longitudinal cross members 7, 8, on the underside of which two double wheels 9, 10 and 11, 12 are arranged to form a horizontal

7461.3 - 7 - 26.01.2001

Axle are rotatably mounted. In addition, the wheels 9 to 12 can each be rotated about a vertical axis with the help of a turntable (not shown in detail), so that the alignment of the double wheels 9 to 12 with respect to the respective longitudinal cross members 7, 8 can be changed.

The double wheels 9, 10 roll on a first running surface and the double wheels 11, 12 on a second running surface 14 parallel thereto. The running surfaces 13, 14 are in turn each mounted on an I-profile beam 15, 16 which is supported by the steel structure 1 (see in particular Figure 2).

In the middle of the second running surface 14 on the right in Figures 6 and 7, a guide rib 17 is attached, which is overlapped by guide members 18 having a complementary recess (see Figure 10). A guide member 18 is connected to the pivot of an associated double wheel 11 or 12 in such a way that it rotates this double wheel 11 or 12 around the vertical axis in accordance with the course of the guide rib 17. In this way, the double wheels 11, 12 follow the running surface 14. The double wheels 9, 10 associated with the first running surface 13 on the left in Figures 6 and 7, on the other hand, are designed as pure trailing wheels; that is, no separate guide means are provided for influencing the angular position of the wheels around their vertical axis of rotation. In this way, the accuracy requirements for the guide means with which the transport carriages 5 are held on the running surfaces 13, 14 0 can be kept low.

The vehicle bodies 4 are carried on the transport carriages 5 by means of a dipping device which comprises a swivel device 5 on each side of the vehicle bodies 4. Each of these swivel devices

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has a swivel arm 50, 51 which can swivel in a manner to be described in a vertical plane that runs parallel to the conveying direction. For this purpose, each swivel arm 50, 51 is connected to the output shaft of a gear 54, 55 via a stub shaft 52, 53 that runs perpendicular to the conveying direction. The gear 54, 55 is attached to the respective longitudinal cross member 7, 8 of the transport carriage 5 approximately in its middle area. It is driven by a motor 56 or 57 which is flanged to the side of the gear 54, 55.

The rear ends of the swivel arms 50, 51 in the direction of movement are connected in an articulated manner to a bracket 58, 59 which extends vertically downwards from the corresponding swivel arm 50, 51 in the normal transport position shown in Figure 4. The lower ends of the brackets 58, 59 are connected to one another via a cross-beam 60 which runs vertically to the direction of movement and which in turn is rigidly connected to the middle area of a

Support platform 61 for the vehicle body 4. The extension direction of the two tabs 58, 59 runs perpendicular to the plane of the support platform 61.
25

The angular position which the brackets 58, 59 assume in relation to the swivel arms 50, 51 is determined by an adjustment device which bears the reference number 62 or 63. Each of these adjustment devices 62, 63 comprises a rod with two parallel push rods 64, 65 or 66, 67, which are connected to one another at their opposite ends via a connecting bracket 68, 69 or 70, 71. The connecting brackets 69 and 71 which are at the rear in the direction of movement are rigidly attached to the cross member 60 at their lower end.

J «

7461.3 - 9 - 26.01.2001

fixed.

The connecting plates 70, 71 located at the front in the direction of movement, however, are each rigidly connected to a stub shaft, which is not visible in the drawing because it extends coaxially through the associated stub shaft 52, 53, which is designed as a hollow shaft. These additional stub shafts also run through the gears 54, 55 and are coupled to the output shafts of further gears 78, 79, which are attached to the sides of the gears 54, 55. Drive motors 80, 81 are also flanged to the gears 78, 79.

The front ends of the two pivot arms 50, 51 together carry a counterweight 88, so that the torques acting on the stub shafts 52, 53 are approximately balanced when the vehicle body 4 is attached.

The double wheels 19 to 12 of the transport carriages 5 are not driven themselves. Rather, the forward propulsion of the transport carriages 5 is achieved via a separate drive, which is explained in more detail below with reference to Figures 5 to 10.

Two vertically aligned, stationary drive flanges 26, 27 extend parallel to the two running surfaces 13, 14. These each interact with a press roller drive 28 or 29, which is attached to the side surface of the adjacent longitudinal cross member 7, 8 by means of a bracket 0 3 0 or 31. The press roller drives 28, 2 9 each comprise an electric drive motor 32 and a drive gear 34, 35. The latter drives the parallel, vertical axes of two press rollers 36, 37 or 38, 3 9, which are pressed from both sides against the respective associated drive flange 26 or 27.

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- 10 -

7461.3 - 10 - 26.01.2001

■If the drive motors 32, 33 are energized, the press rollers 36, 3 7 and 38, 3 9 run on the respective side surfaces of the drive flanges 26, 2 7 and thereby move the transport carriage 5 forward on the running surfaces 13, 14.

Each transport carriage 5 comprises its own carriage control, under the regime of which it carries out both its translational movement along the running surfaces 13, 14 and the immersion movement of the vehicle bodies 4.

The overall function of the dip coating system described above is as follows:

The vehicle bodies 4 to be painted are each placed on their own transport carriage 5 and thus fed into bath 2. If the leading end of a vehicle body 4 has reached the beginning of bath 2, the carriage control decides whether this vehicle body 4 should be immersed in this bath 2. If this is the case,

the immersion process is initiated. This can be carried out with the help of the described swivel device in very different kinematics, as will now be explained in more detail with reference to Figures 4 and 5. 25

The starting point for the analysis is Figure 4, which, as already mentioned, represents the "normal" transport position of the transport carriage 5. In this position, the swivel arms 50, 51 as well as the support platform 610 and the body 4 attached to it run horizontally.

Now it is assumed that the swivel arms 50, 51 are swiveled by a certain angle by supplying the motors 56, 57 acting on the gears 54, 55. The drive motors 80, 81 of the adjustment devices 62, 63 should be supplied with current during this movement in such a way that

- Ii -

7461.3 - 11 - 26.01.2001

so that the tabs 58, 59 rotate by the same angle. Then the geometrical arrangement of the individual components of these adjustment devices, namely the push rods 64, 65, 66, 67 and the connecting tabs 68, 69, 70, 71, does not change with respect to the pivot arms 50, 51. The support platform 61 and the body 4 therefore initially continue to run parallel to the direction of the pivot arms 50, 51; they follow the pivoting movement of the pivot arms 50, 51 by the same angle. The support platform 61 is raised in the process. The articulation points between the pivot arms 50, 51 and the connecting tabs 58, 59 at the rear in the direction of movement move in circles whose diameter corresponds to the distance between these articulation points and the axes of the stub shafts 52, 53.

Instead of the pivoting movement described above, in which the support platform 61 and pivot arms 50, 51 remain parallel, it is possible to use the adjusting devices 62, 63 to change the angular position of the connecting plates 58, 59 and thus the angular position of the support platform 61 and the vehicle body 4 relative to the pivot arms 50, 51. This is done by appropriately supplying current to the drive motors 80 and 81. This pivots the connecting plates 68, 70 located at the front in the direction of movement. The pivoting movement of these connecting plates 68, 70 is transferred via the push rods 64, 65, 66, 67 to the rear connecting plates 69, 71, which leads to a pivoting of the support platform 61 and the vehicle body 4 relative to the pivot arms 50, 51. In this way it is e.g. For example, it is possible to obtain the position of the vehicle body 4 shown in Figure 5.

Of course, the movements achieved by pivoting the pivot arms 50, 51 and by operating the

¹²

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The movements caused by the adjustment devices 62, 63 are carried out simultaneously and thus superimposed. The translational movement of the transport carriages 5 can be superimposed on all of this, again independently.

A possible sequence of movements when immersing a vehicle body 4 in a bath 2 is as follows: First, the transport carriage 5 is driven over the bath 2 until the front area of the support platform 61 is above the bath 2 up to approximately behind the connecting strap 71. The support platform 61 is now positioned approximately vertically by appropriately supplying current to the motors 80, 81 which actuate the adjustment devices 62, 63. The front area of the vehicle body 4 is immersed in the bath 2 a short distance behind the front wall of the bath 2. The swivel arms 50, 51, which have previously run horizontally, are now swiveled anti-clockwise with the aid of the electric motors 56, 57, so that the rear ends of the swivel arms 50, 51 which support the support platform 61 are brought downwards into the bath 2. During this swiveling movement, the adjustment devices 62, 63 are simultaneously actuated so that the vertical alignment of the support platform 61 is maintained. At the same time, the drives 28, 29 of the transport carriage 5 are activated; the transport carriage 5 moves backwards during the described swiveling movements of the swivel arms 50, 51 and the transport platform 61 so that the distance between the support platform 61 and the adjacent front wall of the bath 2 remains approximately constant. In this way, the vehicle body 4 is immersed practically vertically into the bath 2.

Once a sufficient immersion depth has been reached, the swiveling of the swivel arms 50, 51 is stopped. Now, with the help of the two adjustment devices 62, 63, a

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Pivoting movement of the support platform 61 back to the horizontal is initiated. To ensure that the support frame 61 does not hit the adjacent front wall of the bath 2 during this pivoting movement, the transport carriage 5 is moved linearly by activating the drives 28, 29 5 so that the rear end of the support frame 61 moves downwards at an approximately constant distance from the front wall of the bath 2. Once the support frame 61 has reached the horizontal alignment, the adjustment devices 62, 63 are stopped. The body 4 now moves through the bath 2 in a horizontal alignment with the help of the transport carriage 5. If necessary, a rocking movement of the support platform 61 can be caused during this movement by appropriately energizing the motors 80, 81 of the adjustment devices 62, 63 in opposite directions.

Once the transport carriage 5 has reached the end of the bath 2, the support platform 61 is lifted out of the bath 2 again by a combined pivoting movement of the pivoting arms 50, 51, the adjustment devices 62, 63 and, if necessary, a superimposed linear movement of the entire transport carriage 5 and brought into the "normal" transport position of Figure 4. The movement sequence can be the opposite of the immersion process or can also take place with completely different kinematics.

Depending on requirements, the translational movement of the transport carriage 5 can be slowed down or stopped when the vehicle body 4 is submerged.

If necessary, the vehicle body 4 can be brought into different angular positions above the bath 2 in order to allow the paint to run off and drip off as completely as possible into the associated bath 2 and in this way to minimize the carryover of paint.

·* . &iacgr; 2

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¹ ren. Then, by actuating the press roller drives 28, 29, the translational movement of the transport carriage 5 is resumed, if necessary at a higher speed, until the vehicle body 4 has reached, for example, another bath 3 following in the direction of movement.

There, the same processes can be repeated as described for the first bath 2.

In certain painting systems, different vehicle bodies 4 follow one another and have to be treated in different ways. This is easily possible with the painting system described. For example, a bath 2 can be completely driven over; the vehicle body 4 can also be immersed in the bath 2, 3 in question with a backwards, combined swivel and translation movement.

Since, as mentioned, successive vehicle bodies 4 can be treated in different ways in the baths, different distances can arise between successive transport carriages 5. These different distances can be equalized again if desired by corresponding acceleration or deceleration of successive transport carriages 5.

At the beginning of the painting system there is a loading station (not shown) at which the individual vehicle bodies 4 are placed on a stationary transport trolley 5 and secured to it. In a corresponding manner, at the end of the painting system there is a removal station at which the vehicle bodies 4 are removed from a stationary transport trolley 5. Both the loading and the removal stations can be designed as lifting stations. In the removal station 5, the emptied transport trolley 5 is lowered downwards,

is -

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until the running surfaces 13, 14, which also continue into the receiving station, are aligned with parallel running surfaces that extend back to the loading station in a basement of the steel structure 1. The empty transport carriages 5 are brought to the loading station on these running surfaces below the baths 2 in the opposite direction of the arrow 6, which can be done at a higher speed. In the loading station, the transport carriages 5 are brought back to the level of the upper running surfaces 13, 14 and, as already described, equipped with new vehicle bodies 4 to be painted.

Of course, the transport trolleys 5 can also be returned to the entrance of the facility in another way.

As can be seen in particular from Figure 1, all conveyor technology components of the described painting system are located to the side of the bath 2, so that the liquid in the bath 2 cannot be contaminated by these conveyor technology components.

Claims (8)

1. Plant for treating, in particular painting, objects, in particular vehicle bodies, with (a) at least one bath containing a treatment liquid, in particular a varnish, in which the objects are to be immersed; b) a conveyor device with which the objects can be guided through the system in a continuous or intermittent translational movement; c) a plurality of immersion devices, each of which carries an object on a support structure connected to the conveyor device via a connecting structure and is capable of immersing this object in the bath, characterized in that a) the connecting structure comprises at least one pivot arm ( 50 , 51 ) which is pivotably connected to the conveyor device ( 5 ) about a first axis, and a drive device ( 54 , 55 , 56 , 57 ) associated with the pivot arm ( 50 , 51 ) with which the pivot arm ( 50 , 51 ) can be pivoted; b) the support structure ( 61 ) is pivotably connected to the pivot arm ( 50 , 51 ) about a second axis which is at a distance from the first axis; and c) a drive device ( 78 , 79 , 80 , 81 ) is provided, with which the support structure ( 61 ) can be pivoted about the second axis relative to the pivot arm ( 50 , 51 ). 2. Installation according to claim 1, characterized in that the drive device ( 78 , 79 , 80 , 81 ) for pivoting the support structure ( 61 ) relative to the pivot arm ( 50 , 51 ) is arranged at a point which does not dip into the bath ( 2 ) when the pivot arms ( 50 , 51 ) are pivoted, and is connected to the support structure ( 61 ) via a mechanical adjustment device ( 62 , 63 ). 3. Installation according to claim 2, characterized in that the adjusting device ( 62 , 63 ) has a rod ( 64 , 65 , 66 , 67 ). 4. Installation according to claim 3, characterized in that the adjusting device ( 62 , 63 ) comprises two rods ( 64 , 65 , 66 , 67 ) which are articulated on the one hand to a part ( 70 , 71 ) rigidly connected to the support structure ( 61 ) and on the other hand to a part ( 68 , 69 ) rigidly connected to the output shaft of the drive device ( 78 , 79 , 80 , 81 ) in such a way that they never reach a dead center at the same time. 5. Installation according to claim 2, characterized in that the mechanical adjusting device comprises a chain. 6. Installation according to one of claims 2 to 5, characterized in that the output shaft ( 52 , 53 ) of the drive device ( 54 , 55 , 56 , 57 ) of the pivot arm ( 50 , 51 ) is hollow and the output shaft of the drive device ( 78 , 79 , 80 , 81 ) for pivoting the support structure ( 61 ) is guided coaxially through the output shaft ( 52 , 53 ) of the drive device ( 54 , 55 , 56 , 57 ) of the pivot arm ( 50 , 51 ). 7. Installation according to one of the preceding claims, characterized in that the pivot arm ( 50 , 51 ) carries a counterweight. 8. Installation according to one of the preceding claims, characterized in that the swivel arm cooperates with an energy storage device which is able to temporarily store the energy released during the downward movement of the end of the swivel arm connected to the support structure in order to return it again during its upward movement.