EP4411298B1 - Drying device and method for drying a dip-coated body for a motor vehicle - Google Patents

Description

The invention relates to a drying device for drying a motor vehicle body following dip-coating of the body. The drying device has a holding zone designed to maintain a heated state of the body. Furthermore, the drying device has a cooling zone, wherein the cooling zone is arranged downstream of the holding zone in the conveying direction of the body through the drying device. The holding zone and the cooling zone are delimited from the surroundings of the drying device by a housing of the drying device. Furthermore, the invention relates to a method for drying a motor vehicle body using such a drying device.

If cathodic dip painting (CDP) is used to dip paint the vehicle body, a drying device immediately downstream of the dip painting process can also be referred to as a CDP dryer. In the manufacture of motor vehicles, it may be arranged that after leaving the cooling zone of such a CDP dryer, the body is transported to another processing station where the body is sealed. Sealing materials applied during this process can then be cured in a separate, subsequent dryer.

If pasty polyvinyl chloride (PVC) is used as a sealing material to seal the body, this Separate dryers are referred to as PVC dryers. In the PVC dryer, the body is reheated to cure the previously applied sealing material. Heating bodies twice in this way—once in the KTL dryer and then again in the PVC dryer—is disadvantageous, particularly given the associated increased energy consumption and space requirements.

The US 7 043 815 B2 describes a device for applying a flowable material to a vehicle body during the manufacture of a motor vehicle. The material expands at temperatures that may occur during a paint drying stage or in an electroplating process.

The US 2017/0203580 A1 describes a process for printing on a vehicle body. A paste-like sealing material is applied to the body at the end of a furnace section. A cooling process is then carried out, in which the body is conveyed through an oven to dry or cure a sealing film.

The DE10 2008 036322 A1 , DE 10 2013 004136 A1 , EP 2 422 153 B1 , US 2021/095923 A1 and DE 10 2020 213945 A1 describe drying devices for drying a body for a motor vehicle according to the preamble of claim 1.

The object of the present invention is to provide a drying device of the type mentioned at the outset, by means of which a particularly high efficiency can be achieved in motor vehicle production, and to provide a corresponding method for drying a body for a motor vehicle.

This object is achieved by a drying device having the features of patent claim 1 and by a method having the features of patent claim 10. Advantageous embodiments with expedient further developments of the invention are specified in the dependent patent claims and in the following description.

The drying device according to the invention for drying a motor vehicle body following dip-coating of the body comprises a holding zone. The holding zone is designed to maintain a heated state of the body. The drying device has a cooling zone, wherein the cooling zone is arranged downstream of the holding zone in the conveying direction of the body through the drying device. The holding zone and the cooling zone are delimited from an environment of the drying device by a housing of the drying device. The drying device has a processing zone arranged between the holding zone and the cooling zone. At least one robot is arranged in the processing zone, wherein the at least one robot is designed to arrange at least one sealing material on the body.

By means of the at least one robot, the at least one sealing material can be applied to the body during operation of the drying device or during the production of the motor vehicle, before active cooling of the body, which has previously been heated within the drying device, takes place in the cooling zone. Accordingly, during operation of the drying device, the at least one sealing material is applied to the still relatively hot body by means of the at least one robot. This means that an advantageous change in the state of the at least one sealing material can be achieved through the heat or residual heat of the body. In particular, this heat or residual heat of the body can be used to change the state of the at least one sealing material, whereby this change in state usually takes place in a separate dryer downstream of the drying device or downstream of the drying device during the production of motor vehicles.

Accordingly, a separate dryer, such as a PVC dryer, is no longer necessary. Consequently, there is no need to reheat the body in such a separate dryer. Since the additional heating of the body for curing or hardening the at least one sealing material in a separate dryer is no longer necessary, a considerable amount of energy can be saved during the production of the motor vehicle.

Furthermore, the space required for manufacturing the motor vehicle with the body is reduced because the additional dryer, which can be located downstream of the drying device comprising the processing zone with the at least one robot, is eliminated. Rather, such an additional, usually separate dryer is integrated into the drying device in the present case, utilizing the residual heat of the at least one body in the processing zone.

Particularly due to the reduced energy consumption and the reduced space requirement, a particularly high level of efficiency in motor vehicle production can be achieved by the drying device, which has the processing zone arranged between the holding zone and the cooling zone.

The passive cooling of the at least one body during operation of the drying device in the processing zone following the holding zone, in which the at least one body is exposed to heat, can thus be utilized for further added value. The passive release of heat by the at least one body takes place in the processing zone before reaching the cooling zone, in which the at least one body is preferably actively cooled during operation of the drying device.

Due to the provision of the processing zone, the cooling of the body during operation of the drying device is slower than would be the case if the cooling zone followed immediately after the holding zone, i.e. if the processing zone were not provided between the holding zone and the cooling zone. This very slow cooling of the Body, which initially takes place in the processing zone in which the at least one robot applies the at least one sealing material during motor vehicle production, and which is then continued in the cooling zone, advantageously leads to a particularly extensive avoidance of distortion of the body.

This is based on the realization that at least partial distortion of body components can occur if the body cools down very quickly, for example by providing a comparatively short cooling zone with a correspondingly high cooling rate. This is avoided in this case by providing the processing zone, so that the problems associated with body distortion can be largely avoided.

Furthermore, by applying the at least one sealing material to the body using the at least one robot arranged in the processing zone, the formation of bubbles or air pockets in the sealing material can be advantageously avoided. This is based on the finding that such bubble formation can occur if a volume of comparatively cold air is trapped during the application of the sealing material to the body, as would be the case if the sealing material were applied to a body that had already cooled down.

If, in such a case, the enclosed, previously cold air volume is heated in a subsequent dryer (which may be provided in the painting process, for example, to dry another coating material applied to the body), this can lead to undesirable bubble formation in the sealing material. This is because, in this case, the bodywork coated with the sealing material is introduced into the subsequent dryer when the sealing material has already gelled, or has reduced flowability, or the sealing material has already at least partially cured.

Precautions can be taken to prevent such blistering. For example, a heating device, such as an induction heater and/or an infrared radiator, can be used to heat the bodywork at the points where the sealing material is to be applied before applying the sealing material. Additionally or alternatively, it is possible to use a two-component sealing material to prevent blistering at sealing points on the bodywork, such as sealing seams or the like. However, such measures are costly and/or energy-intensive, particularly due to the separate heating or the use of complex sealing materials.

In the present case, the effort associated with such measures can be advantageously avoided. This is because when the at least one sealing material is applied to the still relatively hot body by means of the at least one robot, a volume of relatively cold air is not trapped. Rather, even if air is trapped by the sealing material, the trapped air is comparatively hot. This prevents a heat-induced expansion of the volume of air possibly trapped in the body by the at least one sealing material during a subsequent heating process. Consequently, the formation of bubbles in the sealing material is easily and reliably avoided. This is advantageous.

By providing the housing of the drying device in the holding zone, it can be advantageously achieved that heat, which is applied to the body during operation of the drying device in the holding zone in order to maintain the heated state of the body, does not escape into the environment of the drying device or is at least prevented from escaping into the environment of the drying device.

The provision of the enclosure in the cooling zone advantageously ensures that the body does not cool down too quickly while the drying device is in operation. Furthermore, the provision of the enclosure in the cooling zone makes it very easy to ensure that, for example, usable fresh air for actively cooling the body in the cooling zone remains in the vicinity of the body, allowing this fresh air to effectively absorb the heat emitted by the body. This ensures efficient cooling of the body in the cooling zone while the drying device is in operation.

Due to the provision of the housing at least in the area of the holding zone and the cooling zone of the drying device, the drying device is designed in the manner of a tunnel, i.e. as a device which is essentially closed in the circumferential direction and through which the bodies of the motor vehicles are conveyed in the conveying direction during operation of the drying device.

If cathodic dip painting (CDP) is used for the dip painting of at least one body, the drying device can be referred to as a CDP dryer. This is because the drying device is installed downstream of the cathodic dip painting and serves to dry the dip paint applied to the body during the cathodic dip painting.

Preferably, the processing zone is separated from the surroundings of the drying device by the housing of the drying device. This ensures, on the one hand, that heat from the body in the processing zone is prevented from escaping into the surroundings of the drying device. Consequently, the heat from the body can be used particularly advantageously during operation of the drying device to change the state of the sealing material that can be applied in the processing zone by means of the at least one robot.

Furthermore, the enclosure of the drying device, preferably provided in the processing zone, ensures that exhaust gases generated during the drying of the dip paint do not enter the area surrounding the drying device unhindered. This is particularly advantageous given that, in motor vehicle manufacturing or during the painting process, the drying device is usually located in a closed building in the form of a paint shop, in which people are working. Accordingly, the provision of the enclosure in the processing zone prevents these people from being affected by exhaust gases escaping from the processing zone.

Preferably, in the processing zone, at least one inner side of at least one wall of the enclosure is spaced further from a central axis of the drying device oriented in the conveying direction than in the holding zone. Accordingly, the drying device can be extended or enlarged in at least one direction, such as the lateral direction and/or the vertical direction, in the processing zone.

This is particularly advantageous for easily accommodating the at least one robot in the processing zone. Furthermore, it is particularly easy to ensure that the at least one robot is minimally restricted in its mobility and can perform movements that serve to arrange the at least one sealing material on the bodywork without hindrance. It is therefore advantageous if the processing zone is configured as an enlarged region of the housing in at least one direction oriented perpendicular to the central axis.

Preferably, during operation of the drying device, at least two car bodies can be conveyed side by side through the processing zone perpendicular to the conveying direction. Accordingly, a conveying path coming from the holding zone, along which the car bodies are conveyed during operation of the drying device, can be arranged in the processing zone in at least two conveyor lines may be branched, split, or divided. In this way, it is possible, in particular, to reduce the conveying speed in the processing zone at which the car bodies are conveyed in the conveying direction through the drying device during operation of the drying device. This facilitates the application of the at least one sealing material to the respective car body by means of the at least one robot.

The drying device preferably has at least one temperature control means in the processing zone, which is designed to control the temperature of a partial area of the processing zone comprising the at least one robot. By means of the temperature control means, it can be ensured during operation of the drying device that a temperature prevails in the partial area of the processing zone in which the at least one robot is arranged, which is advantageous for the uninterrupted operation of the at least one robot. By means of the at least one temperature control means, it can also be advantageously achieved that the at least one robot is not adversely affected by heat emitted by the heated bodywork.

In addition, the temperature control means can advantageously prevent undesirably rapid cooling of the body in the processing zone. Relative to a typical room temperature of, for example, approximately 25°C, the temperature control means can accordingly increase the temperature in the sub-region of the processing zone in which the at least one robot of the drying device is located. However, relative to the temperature of the holding zone, the temperature control means preferably reduces the temperature in that sub-region to ensure unimpaired operation of the at least one robot.

The at least one temperature control means can be designed in particular as a blower, because a blower can be used to very reliably and the part of the processing zone in which the at least one robot is arranged can be tempered with little effort.

By designing the temperature control medium as a fan, thermal shielding of the portion of the processing zone in which the at least one robot is located can also be achieved simply and effectively. The warm air envelope provided by the fan particularly effectively prevents the undesirably rapid release of heat from the at least one body into the environment in the processing zone.

In particular, the temperature control means can be configured to set a temperature of approximately 30°C to approximately 60°C, in particular a temperature of approximately 40°C to approximately 50°C, in the partial region. For example, the temperature control means can set a maximum temperature of approximately 50°C in the partial region. At such temperatures, a largely unimpaired operation of the at least one robot, which arranges the at least one sealing material on the body during operation of the drying device, is possible. This is advantageous.

Preferably, the temperature control means is designed to introduce exhaust air originating from the cooling zone and used in the cooling zone to cool the body into the sub-region of the processing zone. In this way, the exhaust air already generated in the cooling zone can be advantageously used to temperature-control the sub-region of the processing zone in which the at least one robot is arranged. This is conducive to efficient, in particular energy-efficient, operation of the drying device. Furthermore, by means of the exhaust air originating from the cooling zone and used in the cooling zone to cool the body, a temperature suitable for trouble-free operation of the at least one robot can be set very easily and with little effort in the sub-region of the processing zone in which the at least one robot is arranged.

By ensuring that the temperature control agent sets a temperature in the partial area during operation of the drying device that is higher than normal room temperature, i.e., higher than a temperature of, for example, approximately 25°C, undesirably rapid cooling of the body in the processing zone can be advantageously avoided. This is particularly advantageous, in particular, for preventing warping of the body or parts of the body. Preventing warping is particularly advantageous for body parts with thin walls.

The drying device preferably has at least one shielding device in the processing zone, which is designed to reduce the exposure of the at least one robot to heat emitted by the body. For example, the at least one shielding device can be designed in the manner of a partition wall or the like. The shielding device makes it particularly easy to ensure that the bodies emerging from the holding zone during operation of the drying device do not cause any heat-related impairment of the operation of the at least one robot.

Preferably, the at least one shielding device is designed to be mobile, so that the shielding device can be arranged where necessary, wherever this is advantageous for the purpose of thermally shielding the at least one robot. In particular, this ensures that the at least one shielding device does not impede movements of the at least one robot during the application of the sealing material, yet still ensures thermal shielding of the at least one robot.

For example, the at least one shielding device can then release access to the robot if this is useful for applying the at least one sealing material and otherwise ensure particularly extensive shielding of the robot against exposure to heat.

Preferably, the at least one robot is designed to arrange at least one sealing plug on the body as the at least one sealing material, which sealing plug is designed to close an opening in the body. This is based on the knowledge that such openings in the body are usually provided so that dip paint can drain out of the body or run out after the body has been dip-coated. Furthermore, dip-coating is usually preceded by at least one cleaning process, in which the body can be immersed in a cleaning bath, for example. A corresponding cleaning fluid used in the cleaning bath can also drain easily out of the body via the at least one opening formed in the body.

If the at least one robot is configured to close corresponding openings in the body using the at least one sealing plug, the heat present in the processing zone or residual heat of the body can be used to create a particularly tight connection between the sealing plug and the body. This is advantageous.

Additionally or alternatively, the at least one robot is preferably configured to arrange at least one damping means on the body as the at least one sealing material. Such damping means are particularly advantageous for improving the acoustic behavior of the body and/or damping vibrations or the like introduced into the body, for example, during operation of the motor vehicle. Furthermore, such damping means can advantageously provide thermal insulation of the body.

If the at least one robot is designed to arrange the at least one damping means on the body, the heat of the body present in the processing zone can advantageously be used for this purpose used to achieve a robust and secure mounting of the damping device to the body. This is advantageous.

The at least one sealing material, which can be arranged on the body in the processing zone of the drying device by means of the at least one robot, preferably ensures that the areas of the body exposed to the at least one sealing material are sealed against the ingress of water. For example, this can prevent water originating from the environment of the motor vehicle from entering a passenger compartment and/or an engine compartment of the motor vehicle during operation. This is particularly advantageous in the area of an underbody of the motor vehicle.

Additionally or alternatively, corrosion protection can be advantageously provided by the at least one sealing material, which is applied to the body by the at least one robot during operation of the drying device. This is also particularly advantageous in the area of the underbody of the motor vehicle.

Preferably, the at least one robot is configured to apply at least one flowable sealant to the body as the at least one sealing material. The at least one flowable sealant can be brought into a state of at least reduced flowability in the processing zone by heat emitted by the body. This allows a particularly good bond between the sealant and the body to be achieved.

For example, the heat emitted by the bodywork can cause the sealant to gel or harden, although this gelling or hardening is accompanied by a reduced flowability of the sealant. This promotes a good adhesion of the sealing material to the bodywork and a good sealing effect.

Additionally or alternatively, the at least one robot can be configured to arrange at least one plastic material on the body as the at least one sealing material, which plastic material can be cured in the processing zone by heat emitted by the body. This eliminates the need for an additional dryer to cure the at least one plastic material. This is advantageous in terms of space and energy requirements, since the space and energy requirements for such an additional dryer are then eliminated.

In particular, the at least one robot can be configured to apply the at least one plastic, polyvinyl chloride (PVC), to the body. This plastic is a sealant that is still pasty during application, but which gels or hardens when exposed to heat, i.e., at higher temperatures. For example, the PVC can be used on the body as a sealant and/or as underbody protection. In particular, PVC monomers can be present in the pasty state, which bond with one another via polycondensation when gelling or hardening occurs.

Additionally or alternatively, it is possible to use at least one acrylate and/or at least one polyurethane as the at least one plastic that can be cured by heat emitted by the body. A dryer used to cure such plastics can be referred to as a PVC dryer even if a different plastic than the PVC, which is still pasty upon application, is applied to the body.

Accordingly, the processing zone can be designed in the manner of a PVC dryer, which is thus integrated into the drying device. Therefore, a separate PVC dryer is no longer necessary. This is advantageous, particularly in view of the resulting reduced space and energy requirements.

Preferably, the at least one robot arranged in the processing zone has three translational axes and three rotational axes. This advantageously makes the at least one robot, in particular an industrial robot, particularly suitable for applying the at least one sealing material to designated locations on the body. Such a robot with six axes offers very high and versatile mobility.

In the method according to the invention for drying a motor vehicle body following dip-coating of the body, the body is introduced into a holding zone of a drying device. In the holding zone, a heated state of the body is maintained. The body is introduced into a cooling zone of the drying device, wherein the cooling zone is arranged downstream of the holding zone in the conveying direction of the body through the drying device. The holding zone and the cooling zone are delimited from an area surrounding the drying device by a housing of the drying device. In the method, the body is introduced into a processing zone of the drying device, wherein the processing zone is arranged between the holding zone and the cooling zone. In the processing zone, the at least one robot arranges at least one sealing material on the body.

Accordingly, the at least one robot utilizes the still relatively high temperature of the body coming from the holding zone, which is still present in the processing zone, to apply the at least one sealing material to the still hot or heated body. This advantageously eliminates the need for a separate heating device for changing the state of the at least one sealing material. Consequently, the method enables particularly high levels of efficiency, in particular energy efficiency, to be achieved in motor vehicle production.

The advantages and preferred embodiments described for the drying device according to the invention also apply to the method according to the invention and vice versa.

The invention therefore also includes further developments of the method according to the invention that have features already described in connection with the further developments of the drying device according to the invention. For this reason, the corresponding further developments of the method according to the invention are not described again here.

The motor vehicle that can be manufactured using the body is preferably designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle.

The invention also encompasses combinations of the features of the described embodiments. The invention therefore also encompasses implementations that each have a combination of the features of several of the described embodiments, unless the embodiments are described as mutually exclusive.

Fig. 1

in einer schematischen, seitlichen Schnittansicht eine als KTL-Trockner ausgebildete Trocknungsvorrichtung für eine Lackieranlage zum Lackieren von Karosserien für Kraftfahrzeuge, wobei die Trocknungsvorrichtung zwischen einer Haltezone und einer Abkühlzone eine Bearbeitungszone aufweist, in welcher Roboter Dichtmaterialien applizieren beziehungsweise an den Karosserien anordnen;

Fig. 2

in einer schematischen Schnittansicht von oben eine Variante der Trocknungsvorrichtung gemäß Fig. 1, bei welcher eine Förderstrecke im Bereich der Bearbeitungszone in eine Mehrzahl von nebeneinander angeordneten Bearbeitungslinien oder Förderlinien aufgesplittet ist;

Fig. 3

eine weitere Variante der Trocknungsvorrichtung gemäß Fig. 1, bei welcher die Förderstrecke sowohl im Bereich der Haltezone und der Abkühlzone als auch im Bereich der dazwischen angeordneten Bearbeitungszone eine einzige, durchgängige Förderstrecke beziehungsweise Förderlinie aufweist; und

Fig. 4

schematisch einen vergrößerten Ausschnitt der Bearbeitungszone, welche der Trocknungsvorrichtung gemäß Fig. 3 zugehörig ist.

Exemplary embodiments of the invention are described below. Shown are:

Fig. 1

in a schematic, side sectional view, a drying device designed as a cathodic dip-dryer for a painting system for painting motor vehicle bodies, wherein the drying device has a processing zone between a holding zone and a cooling zone, in which robots apply sealing materials or arrange them on the bodies;

Fig. 2

in a schematic sectional view from above a variant of the drying device according to Fig. 1 in which a conveyor line in the area of the processing zone is split into a plurality of processing lines or conveyor lines arranged next to one another;

Fig. 3

another variant of the drying device according to Fig. 1 , in which the conveyor section has a single, continuous conveyor section or conveyor line both in the area of the holding zone and the cooling zone and in the area of the processing zone arranged therebetween; and

Fig. 4

schematically an enlarged section of the processing zone, which is assigned to the drying device according to Fig. 3 belongs to.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that can be considered independently of one another, each of which also develops the invention independently of one another. Therefore, the disclosure is intended to encompass combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

In the figures, the same reference symbols denote functionally identical elements.

In Fig. 1 In a highly schematic side sectional view, a drying device 10 for drying bodies 12 is shown. Of the bodies 12 for respective motor vehicles, which pass through the drying device 10 in a conveying direction 14, For reasons of clarity, only some are provided with a reference symbol. The conveying direction 14 is Fig. 1 illustrated by an arrow.

Within the context of motor vehicle production, the drying device 10 is particularly associated with a painting system in which the bodies 12 are painted. In this case, the drying device 10 is connected downstream of a painting facility (not shown) in which the bodies 12 are dip-coated. If cathodic dip painting (CDP) is used during the dip-coating process, the drying device 10 can be referred to as a CDP dryer.

The drying device 10 is designed as a continuous-flow dryer. Accordingly, the car bodies 12 enter the drying device 10 at an inlet 16 or inlet. The car bodies 12 exit the drying device 10 again at an outlet 18 of the drying device 10. The drying device 10, apart from an inlet opening in the form of the inlet 16 and an outlet opening in the form of the outlet 18, is essentially closed to the surroundings 20 of the drying device 10 and is thus designed in the manner of a tunnel.

The drying device 10 can be designed such that the bodies 12 the drying device 10 in the vertical direction z (compare Fig. 1 ) at a constant level. However, it is also possible to design the drying device 10 as a so-called A-dryer. In this design of the drying device 10, the inlet 16 and the outlet 18 are arranged lower in the vertical direction z than a partial area of the drying device 10 in which, during operation of the drying device, the bodies 12 are heated and the heated state of the bodies 12 10 is maintained.

Such a design, modelled on the letter A, in which the drying device 10 is accordingly designed as an A-dryer, is shown schematically and by way of example in Fig. 1 shown. This design has the advantage over a dryer through which the bodies 12 pass at a constant level or at a constant height, that heated air can escape less easily from the partial area in which the heating of the bodies 12 and subsequent maintenance of the heated state takes place. However, the structure of the drying device 10 explained below can be applied analogously to a dryer through which the bodies 12 pass during operation of the drying device 10 at a constant level or at a consistently constant height.

The drying device 10 comprises a heating zone 22 in which the car bodies 12 conveyed through the drying device 10 along the conveying direction 14 are exposed to heated air. In the A-design of the drying device 10, which is shown in Fig. 1 As shown, this heating zone 22 is connected to a lifting device 24, which serves to lift the bodies 12 or vehicle bodies from the level of the inlet 16 to the higher level, in which the heating of the bodies 12 takes place during operation of the drying device 10. In the heating zone 22, the bodies can first be exposed to heating air or heated air which has a temperature of approximately 120 °C. While passing through the heating zone 22, the bodies 12 can be further heated during operation of the drying device 10, for example to a temperature of approximately 200 °C to approximately 220 °C.

The heating zone 22 is followed by a so-called holding zone 26. The holding zone 26 is designed to maintain the heated state of the bodies 12. Accordingly, in the holding zone 26, the bodies 12 are exposed to heating air or heated air, whereby the heated air or heating air can have a temperature of about 200 °C to about 220 °C.

Heating devices of the drying device 10, for example in the form of burners for providing the heated air with which the bodies 12 are exposed in the heating zone 22 and in the holding zone 26, are in Fig. 1 not shown in detail for reasons of clarity.

By means of a further lifting device 28, the bodies 12 or vehicle bodies are lowered again to the lower level after passing through the holding zone 26, for example to the level of the inlet 16 or the outlet 18. At this lower level, the bodies 12 are cooled down.

For the purpose of actively cooling the bodies 12, the bodies 12 can be exposed to fresh air in a cooling zone 30 of the drying device 10, i.e., unheated air, which can originate, for example, from the environment 20 of the drying device 10 and/or from the environment of a building in which the drying device 10 is preferably arranged. In this case, the cooling zone 30 is located downstream of the holding zone 26 in the conveying direction 14 of the bodies 12 through the drying device 10. In particular, the outlet 18 of the drying device 10 adjoins the cooling zone 30.

In the present case, the drying device 10 has a processing zone 32 between the holding zone 26 and the cooling zone 30. At least one robot 34 is arranged in the processing zone 32. By way of example and schematically, Fig. 1 two such robots 34 are shown. The robots 34 are designed to arrange at least one sealing material 36 on the bodies 12 passing through the processing zone 32. The sealing material 36 applied by one of the robots 34 to one of the bodies 12 is shown in a highly schematic manner in an enlarged detail 38, which (as well as the entire drying device 10) in Fig. 1 is shown.

In the processing zone 32, the bodies 12, which come directly from the upstream holding zone 26, still have a comparatively high level of heat or residual heat. This residual heat can be advantageously used to gel and/or cure the at least one sealing material 36, which is applied to the respective body 12 in the processing zone 32 by means of the at least one robot 34. In this way, the residual heat of the bodies 12 can be used effectively and in a value-adding manner.

Therefore, a separate dryer downstream of the cooling zone 30 can be dispensed with. Such a separate dryer can, in principle, be provided to dry or cure sealing materials that can be applied to the bodies 12 after the bodies 12 have left the cooling zone 30 at the outlet 18. With such a design of the painting system, the at least one sealing material 36 would have to be applied to the bodies 12 after they leave the drying device 10.

In the present case, however, this step of applying the sealing material 36 is integrated into the drying process during operation of the drying device 10. This is advantageous because it eliminates the need to reheat the car bodies 12 in a separate dryer, such as a PVC dryer, following cathodic dip drying. Because the drying device 10 in this case has the processing zone 32, the provision of the separate dryer can advantageously be dispensed with. This is accompanied by a reduced space requirement and a reduced energy consumption of the paint shop comprising the drying device 10.

In the present case, the holding zone 26 and the cooling zone 30 are separated from the surroundings 20 of the drying device 10 by a housing 40 of the drying device 10. This prevents the heating air in the holding zone 26 and the fresh air in the cooling zone 30 can escape unhindered into the environment 20. In an analogous manner, the heating zone 22 and/or the processing zone 32 are preferably delimited from the environment 20 of the drying device 10 by the housing 40. In the present case, in particular, the processing zone 32 is not designed as an open processing area, but as a closed processing area in which the at least one robot 34 is arranged.

In Fig. 1 the at least one sealing material 36 is shown only schematically. In fact, the at least one robot 34 is preferably designed to apply a plurality of sealing materials 36, for example in the form of sealing plugs and/or an underbody protection and/or a damping agent and/or a flowable sealant and/or a heat-curable plastic, in particular polyvinyl chloride (PVC) which is still pasty upon application, to the hot body 12 or vehicle body. These different embodiments of the sealing materials 36 are not shown separately in the figures. In the present case, the residual heat of the bodies 12 in the processing zone 32 causes the sealing materials 36 mentioned above by way of example to gel and/or harden.

During operation of the drying device 10, it is preferably ensured that an operating temperature of the at least one robot 34 is not exceeded. This ensures high functionality of the robots 34. In particular, it can be ensured that in a sub-region 42 of the processing zone 32 in which the robots 34 are located, although the temperature is higher than the temperature in the environment 20 of the drying device 10, the permissible operating temperature or working temperature of the robots 34 is nevertheless not exceeded.

For example, a temperature in the range of 30 °C to 50 °C can be set in the partial area 42 of the processing zone 32. This ensures, on the one hand, a permanently undisturbed temperature The functionality of the robots 34 is ensured. On the other hand, the temperature in the partial area 42, which is higher than the temperature in the environment 20, prevents an undesirably rapid cooling of the bodies 12 in the processing zone 32.

A tempering means 44, which can be designed in particular as a fan, and by means of which the above-mentioned tempering of the partial area 42 can be realized, is in Fig. 1 shown highly schematically as an arrow. In particular, the temperature control means 44 can be designed as a fan, which introduces exhaust air originating from the cooling zone 30 and previously used in the cooling zone 30 to cool the car bodies 12 into the sub-area 42 of the processing zone 32 in which the robots 34 are located.

Accordingly, in the processing zone 32, the bodies 12 are not cooled by the temperature control medium 44 by blowing on them. Rather, only the area surrounding the robots 34, i.e., the subarea 42 in which the at least one robot 34 is located, is temperature-controlled by the temperature control medium 44. This allows the automated application of the sealing material 36 performed by the robots 34 to be carried out reliably and with process reliability. Furthermore, this ensures that the bodies 12 or bodies cool down significantly more slowly than would be the case without the provision of the temperature control medium 44.

In addition, the exhaust air, which is already heated by blowing air onto the car bodies 12 in the cooling zone 30, can be used very effectively in this way, namely for tempering the partial area 42 of the processing zone 32 comprising the at least one robot 34. The exhaust air from the cooling zone 30 is therefore preferably not simply discharged into the surroundings 20 of the drying device 10 or even (for example, via a chimney) into the surroundings of the building in which the drying device 10 is preferably located. Rather, a sensible use of the exhaust air takes place. In the application zone or processing zone 32, An elevated room air temperature is maintained, which does not impair the functionality of the robots 34 and at the same time prevents rapid cooling of the bodies 12. This is advantageous.

In Fig. 2 a variant of the drying device 10 is shown, in which, during operation of the drying device 10, several bodies 12 can be conveyed perpendicular to the conveying direction 14 side by side through the processing zone 32. Accordingly, a Fig. 2 The conveyor line 46 of the drying device 10, illustrated by a line, is split or divided into a plurality of conveyor lines 48 in the processing zone 32.

This entails that the drying device 10 is wider in the processing zone 32 than in the holding zone 26 and the cooling zone 30. Accordingly, inner sides 50 of walls 52 of the housing 40 are spaced further apart from a central axis of the drying device 10 oriented in the conveying direction 14 in the processing zone 32 than, for example, in the holding zone 26 or in the cooling zone 30.

The central axis of the drying device 10 is not shown in detail in the figures, but essentially corresponds to the axis shown in Fig. 2 conveying direction illustrated by the continuous arrow 14. In Fig. 2 Furthermore, for reasons of clarity, only some of the robots 34 which the drying device 10 has in the processing zone 32 are provided with a reference number.

In Fig. 3 A further variant of the drying device 10 is shown, in which the conveyor line 46 is designed as a single, continuous line. Accordingly, there is no provision for dividing the conveyor line 46 into a plurality of conveyor lines 48 in the processing zone 32. Nevertheless (unlike in Fig. 3 shown), the drying device 10 may be widened in the processing zone 32, in particular to provide sufficient space for the robots 34 which are arranged in the processing zone 32.

In Fig. 4 It is shown in a highly schematic manner that the drying device 10 can have shielding devices 54 in the processing zone 32, for example, designed in the manner of, in particular, flexible or mobile partition walls. The at least one shielding device 54 of the drying device 10 is designed to reduce the exposure of the at least one robot 34 to heat emitted by the body 12.

The at least one shielding device 34 can at least assist in ensuring that the at least one robot 34 does not exceed a predetermined operating temperature or working temperature. Furthermore, the at least one shielding device 34 at least helps prevent undesirably rapid cooling of the car bodies 12 in the processing zone 32.

Overall, the examples show how the drying device 10 can be used to provide a paint dryer, in particular a cathodic dip-dryer, to a painting system with integrated robot application of sealing materials 36, for example in the form of sealing plugs, underbody protection, sealing compounds and damping compounds.

Claims (10)

1. Drying device for drying a body (12) for a motor vehicle, following a dip-coating of the body (12), wherein the drying device (10) has a holding zone (26), configured to maintain a heated state of the body (12), and a cooling zone (30), wherein the cooling zone (30) is mounted downstream of the holding zone (26) in the conveying direction (14) of the body (12) through the drying device (10), and wherein the holding zone (26) and the cooling zone (30) are delimited from the surroundings (20) of the drying device (10) by an enclosure (40) of the drying device (10), characterized in that
   the drying device (10) has a processing zone (32) arranged between the holding zone (26) and the cooling zone (30), in which processing zone at least one robot (34) is arranged, wherein the at least one robot (34) is configured to dispose at least one sealing material (36) on the body (12).
2. Drying device according to claim 1,
   characterized in that
   the processing zone (32) is delimited from the surroundings (20) of the drying device (10) by the enclosure (40) of the drying device (10).
3. Drying device according to any one of the preceding claims, characterized in that
   in the processing zone (32) at least one inner side (50) of at least one wall (52) of the enclosure (40) is spaced further apart from a central axis of the drying device (10) oriented in the conveying direction (14) than in the holding zone (26), wherein during the operation of the drying device (10) in the processing zone (32) at least two bodies (12) can be conveyed through the processing zone (32) next to one another perpendicular to the conveying
   direction (14).
4. Drying device according to any one of the preceding claims,
   characterized in that
   the drying device (10) in the processing zone (32) has at least one temperature control means (44), configured in particular as a fan, which is configured to control the temperature of a subregion (42) of the processing zone (32) comprising the at least one robot (34).
5. Drying device according to claim 4,
   characterized in that
   the temperature control means (44), which is configured in particular to set a temperature of approx. 30°C to approx. 60°C in the subregion (42), is configured to introduce exhaust air originating from the cooling zone (30) and used in the cooling zone (30) for cooling the body (12) into the subregion (42) of the processing zone (32).
6. Drying device according to any one of the preceding claims,
   characterized in that
   the drying device (10) has in the processing zone (32) at least one, in particular mobile, shielding device (54), which is configured to reduce an exposure of the at least one robot (34) to heat emitted by the body (12).
7. Drying device according to any one of the preceding claims,
   characterized in that
   the at least one robot (34) is configured to dispose, as the at least one sealing material (36), at least one sealing plug configured to seal an opening in the body (12) and/or to dispose at least one damping means on the body (12).
8. Drying device according to any one of the preceding claims,
   characterized in that
   the at least one robot (34) is configured to dispose, as the at least one sealing material (36),

   - at least one flowable sealing means on the body (12), which sealing means can be brought into a state of at least reduced flowability in the processing zone (32) by heat that can be emitted by the body (12), and/or

   - to dispose at least one plastic, in particular polyvinyl chloride, on the body (12), which can be cured in the processing zone (32) by heat emitted by the body (12).
9. Drying device according to any one of the preceding claims,
   characterized in that
   the at least one robot (34) arranged in the processing zone (32) has three axes of translation and three axes of rotation.
10. Method for drying a body (12) for a motor vehicle, following a dip-coating of the body (12), wherein the body (12) is introduced into a holding zone (26) of a drying device (10), wherein a heated state of the body (12) is maintained in the holding zone (26), and wherein the body (12) is introduced into a cooling zone (30) of the drying device (10), wherein the cooling zone (30) is arranged downstream of the holding zone (26) in the conveying direction (14) of the body (12) through the drying device (10), and wherein the holding zone (26) and the cooling zone (30) are delimited from the surroundings (20) of the drying device (10) by an enclosure (40) of the drying device (10),
    characterized in that
    the body (12) is introduced into a processing zone (32) of the drying device (10), wherein the processing zone (32) is arranged between the holding zone (26) and the cooling zone (30), and wherein at least one robot (34) arranges at least one sealing material (36) on the body (12) in the processing zone (32).

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