WO1997017140A1

WO1997017140A1 - System for the surface treatment, in particular powder coating, of workpieces

Info

Publication number: WO1997017140A1
Application number: PCT/EP1996/004800
Authority: WO
Inventors: Gerhard Hestermann
Original assignee: Hestermann Gmbh & Co. Beschichtungsanlagen Kg
Priority date: 1995-11-07
Filing date: 1996-11-04
Publication date: 1997-05-15
Also published as: AU7563696A; DE19680942D2; DE19541409A1

Abstract

The invention concerns a system (11) for powder coating or similar surface treatment processes. The system (11) comprises a plurality of functional units (15) over which extends a continuous rectilinear overhead conveyer (14) in which the suspended carriages (13) with workpieces (12) suspended therefrom are hung. On both sides of the treatment region (17) the overhead conveyers (14) extend into a transfer region (16) in which change-over carriages (25) run on rails (26) transversely to the overhead conveyers (14). The change-over carriages (25) can insert and remove the suspended carriages (13) into and from the overhead conveyer (14) and convey them below the latter to the next conveyer. The functional units (15) are independent units with their own drives and are operationally interconnected by the change-over carriages (25) passing through the transfer region (16).

Description

Description:

Surface treatment device. especially powder coating, of workpieces

APPLICATION AREA AND PRIOR ART

The invention relates to a device for surface treatment, in particular powder coating, of workpieces, for example semi-finished products

Various treatment options are known for treatment operations in which relatively large workpieces have to travel longer distances and in particular several stations. So-called handrail tracks, in which hanging trolleys are manually shifted on rails arranged above the treatment area, allow great flexibility , however, require a high level of personnel and an organizational scheme to be followed by the personnel in order to work smoothly

So - called circular conveyors, in which the workpieces are arranged in a specified sequence after the

Conveyor belt system passing through the treatment stations are unsuitable for many parts because of the rigid interlinking of the treatment stations and also the resulting large deflection radii

So-called "power and free" conveyors (P + F), also called drag circuit conveyors, are very complex, which is due to the large number of different components and also the high assembly costs. This system works with a guide profile arranged below a circular conveyor , in the sledge carriage run The coupling between the circular conveyor and the carriage takes place by means of pawls, which can be released when they run onto a runner. nen. This enables the formation of stacks. However, this system requires switches. The danger of an accident with a need for repair is inherent in the system.

All systems are usually suspended from the hall ceiling, which requires a certain building construction and increases the cost of assembly.

TASK AND SOLUTION

The object of the invention is to provide a device for surface treatment, in particular powder coating, and a functional unit therefor, which allows great flexibility of the work processes with a relatively small space requirement and great reliability.

This object is solved by claim 1.

The device can preferably consist of a plurality of straight suspension brackets arranged parallel to one another, at the ends of which transfer sections are arranged. In these, the suspension trolleys are taken over by transfer trolleys that can be moved across the suspension trolley. The transfer trolleys take the trolleys from the overhead conveyors and transport them to any other hanging conveyor. If the adjoining transfer section is free, they can also jump over one or more hanging conveyors, which ensures greatest flexibility. They are preferably designed in such a way that, when empty, they can also pass under a loaded trolley in order to move back into an operating position.

The suspension conveyors can have an uninterrupted conveyor rail over their entire length, including in the transfer section, which does not require switches or other intermediate elements which are prone to failure. As a result, the suspension trolleys can also be moved cheaply in the middle of the hanging conveyor, ie between the ends of one conveyor rail. This allows sections of Ford rails to be flexibly ^" connected to one another

If a trailer truck is lifted from a first Ford rail by a transfer truck, the next trailer truck can move into the transfer area of the first Ford rail while the trailer truck is being transported to a second Ford rail.He does not have to wait until the transfer truck comes back.Moreover, the transfer truck can immediately after it has inserted the hanger carriage to another Ford rail, the transfer car is not needed for transport in the Ford rail. Since the time span for moving in a workpiece overlaps with the time span for the transverse transport of another workpiece to a second Ford rail, time can be saved and a higher output can be achieved. This has an advantageous effect, in particular, in the case of long workpieces which, because of their dimensions, have to travel a greater distance to enter the transfer area and thus require a longer time

In addition to saving time and the resulting saving of time, the systems can be made smaller and more compact since fewer buffer areas are required

In order to be able to drive at different speeds in the treatment and transfer sections and, for example, to be able to carry out the treatment uninterruptedly when a hanger trolley is stopped in the transfer section, separate drives are provided in the treatment and transfer section for trolleys which overlap one another in this way that a flawless transfer from the treatment to the transfer sections is possible.These drives can be drag conveyors, e.g. chain or rope conveyors. The coupling between the trailer carriage and its drive mechanism, for example the drag conveyors, can be done via latches, which do not need to be controlled separately , but can only be designed in such a way that they only cause entrainment in the towing direction. They therefore result in a freewheel in one direction It is particularly preferred to design the drive mechanism with push rods or toothed racks or toothed rack-like chains, which are attached to the suspension carriage and into which toothed wheels engage. For push rods, the stroke, if used in the transfer area, can be limited to a small fraction of the length of the stroller, for example 30 cm. It is therefore possible to use pneumatic cylinders or electric linear drives. The clinches can also be controlled so as not to interfere, for example, with the hanging trolleys being hung up. For this purpose, they can run onto a control cam in the end position, which swivels them out of engagement.

A gear / rack and pinion drive is very effective and easy to assemble in the treatment area. The freewheel gear drive can be arranged by partially movable arrangement, e.g. Avoid tooth-on-tooth interventions on a swing arm. Frequency-controlled electric motors enable an exact and precisely controllable drive.

The suspension trolleys can preferably be designed such that they are designed for lateral removal, removal and insertion into the conveyor rail. The conveyor rail can be, for example, a prismatic rail in which appropriately designed wheels run, to which support brackets of the suspension carriage follow. The suspension trolleys can have a T-shaped side member, which is designed on the one hand to hang the workpieces and on the other hand can engage in a corresponding V-shaped receptacle on the arms of the transfer trolley. As a result, the suspension trolley is securely positioned on the transfer trolley for cross transport and can also be easily hung on a carrier rail of another overhead conveyor

The transfer trolley can drive on the floor. It can be guided in rails which are either laid on the floor or suspended from supporting structures at a distance from the floor. It preferably has a drive contained therein for the transverse movement, ie its travel on the floor or in the rails, and for the lifting movement of a lifting beam running horizontally and parallel to the overhead conveyors, on the arms receiving the suspension carriages are arranged. They protrude from it in the direction of travel of the transfer wagon and are advantageously automatically foldable away, that is to say they can be folded up against the lifting support, so that the lifting support can also move in between hanging trolleys which are closely adjacent.

Depending on the type and performance of the individual treatment stations, one or more overhead conveyors can also be arranged relatively close to each other in parallel. In this way, even several overhead conveyors can have common drives, particularly in the treatment area. For example, only one hanger carriage can be driven by the drag conveyor and the others can take the neighboring ones with them, for example, by interlocking arms. A corresponding offset of the driver arms can even achieve an automatic offset in the longitudinal direction of the individual suspension trolleys desired in the treatment area, for example in order to be able to treat the workpieces offset to one another.

It is also possible to arrange individual overhead conveyors in a laterally displaceable manner, for example in order to adapt these different workpiece widths in the case of several parallel overhead conveyors. Since the transfer carriages are essentially arranged to move freely, they can easily adapt to this change in the system by influencing their control program accordingly.

A great advantage is the extraordinary flexibility of the system. The individual drives of the transfer trolley and the tow conveyor can be controlled by a common electronic control which works together with sensors for the position of the individual sling and transfer trolleys. These can be any non-contact sensors, for example inductive or optical sensors. An optical system for avoiding collisions, for example sensors responding to certain distances, can also be provided. It is also possible to assign a detection system, for example a fixed or also changeable coding in the form of optical, magnetic or mechanical markings, to the suspension carriage assigned to this direct different ^'even in the treatment of various workpieces in sequence or certain objectives

The control unit can have a certain basic program, which contains the different driving and lifting speeds for empty travel or the loaded state, in particular the transfer car, as well as the individual movement sequences for lifting and reinserting the trailer carriages, etc. Through a treatment program which can be influenced by the user However, a certain sequence of operations, sorting, intermediate storage including the double approaching or skipping over of stations and the individual speeds in the processing area can easily be influenced. In spite of this flexibility, it should be possible to position the transfer wagons precisely during their journey transversely to the requirements they are driven in a form-fitting manner with their rails, although it would also be possible to precisely position them electronically with a correspondingly greater outlay, and it is particularly advantageous if the rails for the toothed wheel in this case r of the transfer car are covered with a toothed belt that is fastened to the rail. On this toothed belt, the transfer car runs in a form-fitting manner on the one hand and steamed on the other hand, so that its movement, particularly during acceleration and deceleration, is low in vibration and noise This is of great advantage for the workpieces, in particular in the case of powder coating, because the workpieces should be moved very gently between the powder application and the curing oven. Additional treatment devices can be arranged in the transfer sections into which the transfer carts move, for example, through Lowering in plunge pools, passing through cooling or curing devices, etc. The space is thus used economically

It is also possible, depending on the conditions in the individual treatment stations, including buffer stations, cooling stations or other more passive stations, to arrange the hanging conveyors in different heights. With a corresponding height of the transfer trolleys, only a corresponding basic programming in the electronic control is necessary for them, so that the transfer trolleys can accommodate the different height of the Ford rails can reach or drive under this case, the columns of the transfer car can also be designed telescopically.

A further particular advantage is that an entire device, for example for powder coating, can be assembled from several functional units in a modular manner. In contrast to other devices with the conveyor systems described at the outset, the invention makes it possible to place pretreatment chambers, cooling sections, powder application stations and curing ovens side by side in any number, the individual sections each forming an independent unit with regard to longitudinal conveying and a standardized one Can have length and height. As a result, they can preferably also be designed to be ground-supported, so that only installation is necessary for their assembly. These functional units arranged in parallel and at almost any intervals next to one another are then connected by the cross conveyors formed by the transfer carriages, in which only the rail length has to be adapted to the transverse dimensions of the overall device. It is thus possible for the first time to construct such treatment devices, in particular for powder coating, in a modular manner as a standardized "powder machine", whereby it is not only possible to save manufacturing and assembly costs through the modular production. The previously large expenditure of costs and time for the planning of the individually created systems can also be dispensed with.

Particularly noteworthy is the low space requirement and the adaptability to the respective space conditions, especially with a modular structure. For example, there is no need for space for swivel radii, especially in the case of long workpieces which occur in the case of circular and drag circle conveyors. Due to the possibility of the ground-based arrangement, the requirements for the building statics and training are also reduced, so that the overall device can also be produced much more cost-effectively. Up to now, building costs for devices with such a large area have often been in the order of the purchase costs for the device. The mechanical design of the overhead conveyors gives further advantages. Due to the lateral engagement of the support bracket in the overhead conveyor, this including the drag conveyor drives running therein can form a box which is closed at the bottom, which has the considerable advantage, especially for surface treatment systems, that no abrasion or dirt from the conveyor can fall onto the workpieces underneath . Mechanisms, such as switches, etc., which are constantly to be maintained, are not required, which in turn has a particularly advantageous effect if the treatment stations are at high temperatures or there is a risk of contamination by dusts or liquids. An essential advantage is the reduced precision requirements, in particular compared to P + F systems, which are there in the tenths of a millimeter range and need only be in the millimeter or even centimeter range in the invention. This results, among other things, from the self-centering of the hanger trolley in a V-shaped prism rail, which is simultaneously used to center the hanger trolley when inserted into the prism rail, and from a V-shaped recess in the transfer trolley, into which the hanger trolley is self-centering when it is lifted out can be.

In particular, due to the lack of switches, there is no dependency of the running properties on the different weight of the sledge carriages.

The possibility of driving one or more lanes in one device also improves the effectiveness of the individual treatment stations. For example, a push-through principle can be used to work much more effectively in a chamber furnace and a more precise temperature distribution can be set if, for example, several suspension trolleys move in and out at the same time. The heat losses when opening can also be reduced proportionately. These advantages also result in other stations, for example in pretreatment, where the problem of so-called bath carryover is easier to master than in the case of the more inflexible continuous systems. It should also be emphasized that the use of small, inexpensive individual drives instead of the large central drive required in P + F systems not only reduces manufacturing and assembly costs, but also reduces the need for maintenance. This makes it possible not only to set up the individual functional units but also the individual components largely without mechanical connection to one another and to make the connection only by means of an electrical connection. For example, the individual functional units could be coupled to one another by plug connections and possibly even by a data bus. It is also possible to assign individual control units to the individual functional units, which, for example, contain the basic program settings in the sense of their own operating system and which are supplied with the user programs or settings from a common operating device. The automatic control also avoids loading errors, such as can occur with manual overhead conveyors, and enables perfect process documentation, which is of great importance for quality control.

These and further features emerge from the claims and also from the description and the drawings, the individual features being implemented individually or in groups in the form of sub-combinations in one embodiment of the invention and in other fields and being advantageous and capable of being protected Can represent versions for which protection is claimed here. The subdivision of the application into individual sections and subheadings do not limit the generality of the statements made under these.

BRIEF DESCRIPTION OF THE DRAWINGS

Some exemplary embodiments are shown in the drawings and are explained in more detail below. Show it

Fig. 1 is a schematic perspective view obliquely from above on a

Surface treatment device,

2 is a schematic plan view, partly broken away, of the conveyors in the treatment and transfer sections,

3 to 5 cross sections through a overhead conveyor in the individual areas, according to lines III-V in Fig. 2,

6 is a view of a transfer car,

7 shows a schematic, vertical section through a transfer car according to line VII in FIG. 2,

8 shows a detail of the rail guide for the transfer car in partial section, FIG. 99 shows a schematic diagram in top view of three parallel sling cars with mutual coupling of their towing drive,

9a shows a variant of a driver,

10 is a view along the line X in Fig. 9,

11 and 12 cross sections through the overhead conveyor in the transfer area with variants of the traction drive,

13 to 19 a variant of a transfer trolley in the representation corresponding to FIG. 7 and different working positions of the transfer and trolley in operation, FIG. 20 a transfer trolley which can be moved in rails which are at a distance from the ground,

FIG. 21 is a top view of the transfer truck from FIG. 20. DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

The device 11 shown in the drawings serves for the surface treatment of workpieces 12, in particular for their powder coating. However, it can also be used for other surface treatment processes. The workpieces 12, for which the device 11 is particularly suitable, are usually larger workpieces 12, such as Semi-finished products in the form of tubes, profiles, plates or the like, with a length of more than 3 m to 7 m and possibly also over it

The workpieces 12 are attached to hanger carriages 13, which run on hangers 14. The device 11 is constructed in a modular manner from individual functional units 15, each of which has at least one hanger 14. The hanger 14 are arranged parallel to one another and end on both sides a transfer section 16, between which a treatment section 17 lies

A wide variety of treatment stations are provided in the treatment sections 17. For example, in the case of a powder coating system in the treatment section 17 of a first functional unit 15, a pretreatment chamber 18 for wet cleaning of the workpieces can be provided, which is followed by a water dryer 19 in the same functional unit 15 to dry the workpieces 12 after cleaning

The adjoining functional unit 15 is a cooling section 20, in which the workpieces 12 dried in the water dryer 19 with the use of heat can cool them. At the same time, they serve as a buffer section between the pretreatment chamber 18 and the subsequent two functional units 15 with powder booths 21, in which a plastic - Coating powder is applied automatically and / or with hand guns to the workpieces 12, on which it adheres by electrostatic action. It can be seen that the powder booths 21 do not take up the entire length of the hanging conveyor 14, so that the remaining sections of the Suspenders 14 can also serve as a buffer section. The powder booths 21 are staggered in such a way that a very space-saving arrangement of the two Powder chamber functional units is possible. If the treatment to be carried out there requires more time, they can work in parallel to better utilize all the other functional units 15, or they can be equipped for different powder colors, so that it is possible to carry out the coating in several colors simultaneously in one device 11

In the exemplary embodiment, this is followed by a functional unit 15 with a curing oven 22, in which the plastic powder adhering to the workpieces 12 is melted and hardened under the action of heat. The respective directions of passage of the individual functional units 15 are identified by the arrows 24 in FIG. 1.

The individual functional units 15 are functionally coupled in their transfer sections 16 each by a transfer carriage 25 which can be moved on rails 26 transversely to the overhead conveyors 14. These rails 26 run over the entire transfer area 16 and possibly also a little further, for example in order to load the suspension trolleys 13 with workpieces 12. However, a separate functional unit 15 can also be provided for this, as well as for unloading. Additional treatment devices 89 can also be arranged in the transfer areas 16, into which the transfer carriages 25 drive workpieces 12.

The hanging conveyors 14 thus extend over the entire treatment area 17 and both transfer areas 16 at the ends of the treatment area 17. They stand on support structures 28 which are supported on the floor 69 by means of columns 29. The individual treatment stations 18 to 22 are also ground-based, as is the transfer carriage 25 via its rails 26, so that the entire device 11 is independent of a building construction and only requires a suitable floor 69 for installation. In Fig. 1, the support structure 28 is provided together for a plurality of functional units 15. Since this is a simple portal support construction, this can make sense. However, it is also possible to assign each functional unit 15 its own support structure 28 to be set up independently on the floor 69. Each overhead conveyor 14 can be designed as a continuous longitudinal beam and can thus be self-supporting over longer distances. Intermediate supports are possible without hindering the workpiece flow.

The structure of the overhead conveyor 14 is shown in FIGS. 2 to 5. Each overhead conveyor 14 has in a U-shaped or C-shaped box support 30 a conveyor rail 31 which can run continuously over the entire length of the overhead conveyor 14 including the transfer sections 16. It is a V-shaped prism rail 31, which can come about by arranging an L-profile in the box girder 30, for example at an angle of 45 °. In it run wheels 32 of the suspension carriage 13, which is constructed from a longitudinal member 33 running in the longitudinal direction of the overhead conveyor 14, designed as a T-profile, and attached to it support brackets 34, which have the shape of a lying U, with one end on the longitudinal member 33 are attached and carry at their other end a likewise U-shaped wheel carrier 35 with the bearings for the wheels 32. The wheels 32 have a profile which is pointed or has an annular cutting edge, which preferably includes a more acute angle than the 90 ° angle of the upwardly open prism rail 31 in the example shown. This results in self-centering in the inner apex 36 of the conveyor rail 31 Furthermore, the wheels 32 are distributed substantially uniformly over the entire length of the suspension carriage 13. The suspension trolley 13 is thereby supported over its entire length and can be made less rigid and thus lighter, as a result of which the components carrying the suspension trolley 13 can also be dimensioned weaker and lighter, for example transfer trolleys 25, conveyor rails 31, etc. According to the invention, the wheels 32 can be joined together in groups in an articulated manner, as a result of which the suspension carriage 13 can adapt well to unevenness in the conveyor rail 31.

The workpieces 12 are suspended on the longitudinal member 33 via wire hooks, ropes or chains. The longitudinal member 33 has corresponding holes or hooks. It can be seen that due to the fact that the wheels 32 run vertically above the side member 33 due to the U-shaped support bracket 34, the hanger carriage 13 hangs in a stable position, although its engagement into the conveyor rail 31 from the side and the conveyor rail 31 is closed at the bottom.

The hanging carriages 13 running in the conveyor rail 31 are moved by a drive mechanism, which in the example of FIGS. 2 to 5 consists of drag conveyors 37, 38, each of which is designed as a circulating cable or chain conveyor. FIG. 2 shows that the drag conveyor 37 sweeps over the treatment area 17, while in the transfer areas 16 the drag conveyor 38 runs along the overhead conveyor 14. Both drag conveyors 37, 38 overlap in an area 40 on each side of the treatment area 17 and take over the drive of a hanger carriage 13 from the other tow conveyor 37, 38 there.

Fig. 3 shows that the drag conveyor 37 contains a chain conveyor with a chain 39, which is endlessly guided around a deflection and drive wheel, not shown, on each side. Driver links 41, to which driver 42 are attached, are attached to one or some points of the chain 39 which are spaced apart from one another. They consist of pawls pivotable about an axis 43; which act in one direction, namely in the respective transport direction 24, on the hanger carriage 13, namely on the support bracket 34, but are resiliently or by gravity so that they can be pivoted away in the opposite direction and thus have a longitudinal drive effective in one direction only form. 9a shows a driver 42a which only engages in one direction. After it has snapped in, the driver 42a guides the hanger carriage 13 so that it is pulled in the transport direction 24 and, if the drag conveyor 37, 38 decelerates, is braked in the opposite direction. After the path to be conveyed, the driver 42a is pivoted upward by a run-up 86 and the driver arm 65 is released.

The driver links 41 are guided in a C-shaped profile 44 which runs along the suspension conveyor 14 and which receives the chain 39. The strand of the chain 39 opposite the drive strand carrying the drive links 41 runs on a U-shaped carrier, which also covers the chain 39 downwards. The towing device 37, 38 is designed as an oscillating drive, because the chain 39 does not run continuously, but is moved back and forth, pushing a hanger carriage 13 in front of it. When the towing device 37, 38 returns, the Mit¬ skip 42 take their stops on the hanger carriage 13 or are in a position so that they do not snap in. Therefore, the chain conveyor is very easy to extend, since the driver links 41 and drivers 42, 42a do not need to be equipped to run around the deflection wheels 42, 42a can thus run inside between the two chain runs, which contributes to a space-saving arrangement. From FIG. 3 it can also be seen that the guides 44 of the towing device 37, ie the profile surrounding the chain 39, in the treatment area 17 so runs close above the wheel carrier 35 of the hanger carriage 13 so that it secures the wheels 32 against lifting out of the Ford rail 31

5 shows the cross section of the suspension conveyor 14 in the transfer area 16. While in the treatment area 17 the tow conveyor 37 is formed above the supporting bow 34 and the running gear of the hanging carriage 13 formed by the wheels 32, with the chain center lying horizontally next to one another, it is in the transfer area 16 provided drag conveyors 38 are arranged laterally next to the Ford rail 31 with the chain strands lying essentially vertically one above the other, on the side opposite the support bracket 34. The lower strand of the chain 39, which, like the upper one, has a U-shaped guide 44 is located, the driver links 41, which projects upwards into the space between the runs. The driver 42, as described with reference to FIG. 3, is resiliently mounted on one side and engages a driver tab 45 on the wheel carrier 35

It can be seen that the towing device 38 leaves one side of the Ford rail 31 completely free. In this area the upper towing device 37 is also missing, in the transfer area 16 the hanger carriage 13 can be unhooked by moving upwards and in the drawing to the right, ie be disengaged from the guide 31 4 shows the arrangement in the intermediate area 40 between the treatment area 17 and the transfer area. There are both towing devices 37, 38 so that the hanger carriage 13 can be taken over from one towing device 37, 38 to the other. It can be seen that the two towing devices 37, 38 do not interfere with one another. In this area 40, too, the drive is still secured against being lifted out of the conveyor rail 31. As in the treatment area 17, the box girder 30 can also be closed here except for the passage for the support bracket 34.

In this intermediate area 40 non-contact sensors 46 are provided for the drivers 42 of the towing devices 37 and 38 as well as for the hanger carriage 13. They work together with the driving members 41 or projections 47 provided thereon and the driving tab 45. Their signals are used to coordinate the transfer movements in a schematically indicated control unit 48, which controls the drive motors 49, 50 of the towing devices 37, 38 and can also be connected to the control of the transfer vehicle 25 in order to provide a signal about the presence and the correct positioning of a trolley 13 in

To deliver transfer area 16 as a prerequisite for the action of the transfer car 25.

6 and 7 show the transfer carriage 25. It has a chassis 51 with a chassis 51, which is transverse to the transport direction 52 of the transfer carriage 25 and is in the form of a box girder, and two side cheeks 53 projecting on one side in the transport direction 52. In each of the side walls 53 two running wheels 54 are arranged one behind the other, which run in the rails 26. They can be driven by a drive controlled by a common control unit via a drive (not shown in detail, possibly synchronizing all wheels 26 with one another).

A lifting column 55 extends above the side cheeks 53 on both sides of the transfer carriage 25. In slots 56 on the inside of the likewise box-shaped lifting columns 55, a lifting beam 57 in the form of a crossbar is guided so as to be vertically movable. The corresponding drive can be any longitudinal drives, for example one in the form of a dash-dotted line indicated screw spindle in the lifting column 55, which can be actuated by a drive 59 independently of the travel drive 60 of the transfer carriage 25. The linear drives 58 on both sides of the transfer carriage 25 are synchronized with one another. Arranged on the lifting beam 57 are a plurality of arms 61, in the example shown three arms 61, which protrude substantially horizontally in the same direction as the side cheeks 53. They each have a receptacle 62 on their upper side for the longitudinal beams 33 of the device hanging trolley 13. For this purpose, the receptacle 62 in the example shown is designed in the form of a V-shaped recess, so that the T-profile is centered appropriately therein. 6 and 7 show the transfer carriage 25 with a suspended carriage 13 and workpiece 12 attached to it.

FIG. 7 shows that the arms 61 can be pivoted about an axis 63 that runs vertically close to the lifting beam 57, so that they are pivoted towards the lifting beam 57 by a pivot drive 64 arranged in the lifting beam 57, for example a pneumatic cylinder or an electric motor can be. As a result, the width of the transfer carriage 25 in its upper region is reduced, and it is possible to use the lifting beam 57 to also move between closely adjacent overhead conveyors 14 without influencing adjacent workpieces 12.

1 and 2 it can be seen that each functional unit 15 can have any number of parallel and side-by-side overhead conveyors 14, which can be combined in a common mounting rail. For example, in FIGS. 1 and 2 the respective outer units 15 are provided with three hanging conveyors 14 arranged next to one another. They can be selectively loaded and unloaded if they have the necessary distance to drive the transfer truck 25 in between. If they are very close together, they can be loaded and unloaded successively. Its drive, as shown in FIG. 2, can consist of a set of towing conveyors 37, 38 per hanging conveyor 14. However, it is also possible to provide a common drive for all overhead conveyors 14 of a functional unit 15. The entrainment can then take place either directly, for example by a plurality of driver pawls 42 arranged in the manner of a comb, or indirectly. Such a variant is shown in FIGS. 9 and 10. A towing device 37 takes with its driver pawl 42 a hanger carriage 13 via a lateral driver arm 65 with each of the three hanger cars 13 running parallel to one another in hanger devices 14 has on one side the driver arm 65, which 10 shows a bend 66 downward and on the opposite side two driver arms 67 at a distance from one another, between which the bend 66 engages. If the pawl 42 now takes the uppermost hanger carriage 13 in the transport direction 24, it takes they, with a longitudinal offset determined by the distance between the driver arms 67, also the adjacent hanger carriages 13, and this, also with the corresponding offset, the following ones. In the intermediate area 40, for example, the transfer towing device 38 can be designed such that he grabs all three trolleys 13 and again in the longitudinal direction from each other or three different transfer towing devices 38 can also be provided

FIG. 8 shows a detail of the transfer carriage 25, specifically an impeller 54, which is rotatably mounted in a side cheek 53 and is connected to the motor 60 (FIG. 7) in a drivable manner via a drive shaft 68. The impeller 54 runs in an essentially U-shaped rail 26, which is fastened on the bottom 69. A toothed belt 70 is mounted lengthwise inside the rail 26, with its teeth 71 pointing upwards and with these in corresponding teeth 72 on the outside - Catches of the impeller 54 engages a diagonally inclined flange 73 on each side of the impeller 54 guides it on both sides of the toothed belt 70 so that it also takes over the lateral guidance. This results in a form-fitting and yet elastic, vibration-damped drive. A side flange 74 on one side of the rail 26 can cooperate with a corresponding projection 75 on the side cheek such that the flange 74 of the rail 26 engages over the projection 75 and thus prevents the impeller 54 from lifting off. The transfer carriage 25 can thus be secured against tipping over

FIG. 11 shows a variant of the drive mechanism of the suspension conveyor 14 in the transfer section 16. Instead of the chain drag conveyor 38 shown in FIG. 5, there is a push rod conveyor 38a Its push rod 77 can be moved in the longitudinal direction of the conveyor 14 by an electric, pneumatic or hydraulic linear drive and then carries at its end the driver 42 in the form of the pawl already described for FIG. 5. This embodiment is good for the transfer section 16 Suitable because there is a limited length of axial movement. If necessary, a hanger carriage 13 could also be transported in several movement sections, in which the pawl 42 engages successively on support brackets 34. It is also possible to push the push rod 77 in the top right in FIG. next to the position of the towing device 37a in FIG. 12). The pawl 42, 42a can then engage directly on the support bracket 34. In the end position of the push rod 77, the pawl 42, 42a can be forcibly moved into its "exception" by means of a control curve or bevel, not shown - Engagement position "can be swiveled to secure when hanging a hanger ¬ gens 13 not to bother

Fig. 12 shows a variant of the drive mechanism, in which a gear / rack conveyor 37a is used. A gear 79 is driven by a gear motor 78 arranged on the suspension conveyor 14, which engages in a chain or rack 80 which runs along the suspension carriage 13 via the Carrying brackets 34 or the wheel carriers 35 are arranged. This embodiment secures the hanger carriages 13 against lifting out like the embodiment of the towing device 37 according to FIG. 3 and is therefore suitable for the treatment section 17 of the suspension device 14 by correspondingly different arrangements, for example intervention from the side this version can also be used for the transfer section 16. Instead of a gear 79, a friction wheel or other drive means could also be provided. The drive 78, 79 is arranged on a rocker 90 about the axis 91 so as to be vertically movable to such an extent that a gear engagement is also possible which comes about at the beginning of tooth-on-tooth position

13 shows a transfer carriage 25a which is similar to that described with reference to FIG. 7, with the difference that the arms 61 project horizontally considerably longer and three receptacles 62 are provided one behind the other on this upper side. With this embodiment it is possible to to lift and reinsert three suspension trolleys 13 from three hanging conveyors 14 running parallel to one another.

The rails 26 arranged on the floor 69 of the transfer car 25 interfere in some cases, for example if they frequently have to be climbed or driven over them. FIGS. 20 and 21 show a transfer carriage 25 which can be moved in rails 26 which are arranged at a distance from the floor 69. Two rails 26 are preferably arranged just below the overhead conveyor 14, one being fastened directly next to or being formed by the supporting structure 28 and one being displaced further inwards. So that the hanger carriage 13 with the workpiece 12 can be moved between the rails 26 and then be taken up by the arms 61, the inner rail 26 is interrupted in this area 92. There is a danger if the transfer carriage 25 moves over this area 92 that it tilts sideways to the front. In order to avoid this, according to the invention, the transfer carriage 25 is configured on one side with at least 3, preferably 4, wheels 54, each of which has a greater distance 94 from one another than that the interrupted area 92 is 95 wide. As a result, there are always at least 2, preferably 3, running wheels 54 on the rail 26, as a result of which the transfer carriage 25 is guided in a stable manner. Another possibility is to use an internal rail 26 which guides the wheels 54 of the transfer carriage 25 from above and below. Furthermore, the transfer carriage 25 has at least on this side four running wheels 54, which are arranged at a distance in the transport direction 52 such that two running wheels 54 are always guided in the rail 26, between which there is also a distance in the transport direction 52. As a result, the resulting tipping moment can be absorbed by the guided impellers 54. Despite the fact that two running wheels 54 are always in engagement, it can happen, for example, due to play, that the transfer carriage 25 tilts slightly, which means that the running wheels 54 can get caught when they run back into the rail 26. This is prevented by entry ramps 93 which are arranged on the rail ends in the interrupted area 92. It is also conceivable that the transfer carriage 25 is only guided in a rail 26, which can also be interrupted. This saves material and assembly effort. FUNCTION

The device 11 is operated according to the following method explained with reference to FIGS. 14 to 19

Assuming that the hanger carriages 13, as shown in FIG. 1 in the entrance area 81, are received on the arms 61 of a transfer carriage 25, they are brought into the position shown in FIG. 14. The hanger carriages 13 can be in the position shown in FIG Workpieces 12 have been loaded or come from a separate loading station, for example the same as the cooling section 20

The hanger carriage 13 stands below the lower edge 82 of the hanging conveyor 14 and the columns 55 also end below this lower edge 82. The transfer carriage 25 can therefore also be loaded with a hanger carriage 13 and pass under the hanging conveyor 14 in FIG. 14, the hanger carriage 13 is on the loading side 83 of the Hangefbrderers 14 (right) and below

Fig. 15 shows that it is now raised further, so that it stands with its wheels 32 higher than the limitation of the Ford rail 31 on the loading side 83, since the Ford rail 31 is an isosceles L-profile, the shorter leg of which points towards the loading side 83 , the additional stroke over the later long demand position is not so great. The lifting takes place via the stroke drive 59

In FIG. 16, the converter carriage 25 is now moved so far in its rails 26 via the travel drive 60 (FIG. 7) that the wheels 32 are above the Ford rail 31

Fig. 16 shows that by actuating the lifting drive in the downward direction, the lifting bracket 57 with the arms 61 and thus also the hanger carriage 13 is lowered. The wheels 32 center themselves in the Ford rails 31. Finally, the hanger carriage 13 comes from the arms 61 free because the side members 33 detach from the receptacles 62 when the arms 61 are lowered further. The transfer carriage 23 is now free and, as shown in FIG. 18, can already begin its movement, provided that it moves to the left from the hanging conveyor 14 in FIG. 18, ie does not have to pass the workpieces 12 with its lifting support 57. If it is to be moved to the right, then the lifting carrier 57, as shown in FIG. 19, is moved under the lower edge of the workpieces 12 and passes underneath them. The lifting columns 55 do not interfere because they pass the side of the suspension carriage 13 and workpieces 12. It is preferred to arrange the transfer carriage 25 as shown in FIG. 1, ie with the arms 61 pointing in the transfer area 16 against the main transport direction 52. The loaded suspension trolleys 13 are transported in this direction, so that the start of the transfer trolley 25 can be started earlier in this direction.

A suspension trolley 13 is unhooked in reverse order: the transfer carriage 25 is brought with the receptacle 62 under the suspension trolley 13, either from the underride position in FIG. 19 (if coming from the right) or from the position according to FIG. 18 from (coming from the left). The arms 61 then move up. The longitudinal member 33 or another intended receiving section on the suspension carriage 13 lies in the receptacle 62 (FIG. 17) and the wheels 32 are lifted out of the conveyor rail 31 by further lifting (FIG. 16). The transfer carriage 25 then moves to the right, so that the section of the suspension carriage 13 carrying the wheels 32 comes free from the hanging conveyor 14 (FIG. 15). Thereafter, the lifting bracket 57 is moved with the arms 61 downward via the lifting drive, so that the suspension carriage 13 is below the lower edge 82 of the hanging conveyor 14. In this position, in which the workpieces 12 still hang freely from the floor 69, they can now be moved transversely to it under the overhead conveyor 14 and other overhead conveyors 14.

The acceleration, deceleration and speed values can differ from the operating program of the associated control device and above all as a function of the fact be determined whether the transfer car 25 is loaded with a hanger carriage 13 or not

After a hanger carriage 13 is suspended in the suspension conveyor 14 in the transfer section 16, it is moved by the associated tow conveyor 38 in the direction of the treatment section 17. For this purpose, the associated pawl 42 engages on the driving tab 45 of the hanger carriage 13 approached so that the workpieces 12 do not vibrate as much as possible. In the intermediate area 40, the towing device 37 takes over the further transport. The overlap area could also be missing if it is ensured that, for example, the transfer towing device 38 on the rear support bracket 34 and the towing device 37 in the Treatment section 17 engages the front bracket 34 of a hanger carriage 13

The described transfer carriages 25, because of their lateral arrangement of the lifting columns 55 and the lowerability of the lifting bracket 57 to below the workpieces 12, enable a loaded trailer carriage 13 to be passed under if this is not necessary due to the organization scheme of the overall device 11, for example, by all trailer vehicles 13 are always removed immediately from the transfer area, then the stroke of the lifting bracket 57 can be limited to the hooking-in and hooking-out movement (between the position according to FIGS. 14 and 15). Simpler, short-stroke linear drives 58, 59 can then be used and that Lifting pillars 55 need not be arranged entirely on the outside. This enables a structurally simpler construction and also facilitates a smaller track width of the rails 26

In the treatment area 17 the hanger carriage 13 with the workpieces 12 can now be moved continuously or discontinuously at different speeds depending on the treatment conditions

When he leaves the treatment area 17, a transfer towing device 38 again takes over his transport to the transfer position, where a transfer cart 25 takes him out of the suspension. can lift out challenger 14 in order to place it in the next or another hanging conveyor 14 Instead of the described prism rail 31 with an adapted profile of the wheels 32, other self-centering rails / wheel combinations can also be used, for example a triangular rail with an upper apex and corresponding to V -shaped grooved (diabolo-shaped) wheels or two wheels with V-shaped axes

A data processing program in the control device 48 ensures that the risk of collisions or misdirections is practically excluded. However, if manual action in the treatment area is desired and possible, an optical or collision avoidance system working with proximity sensors can be activated to rule out errors

Claims

Device for surface treatment, in particular powder coating, of workpieces

Expectations

Device for the surface treatment, in particular powder coating, of workpieces (12), for example semi-finished products, consisting of a plurality of functional units (15), each of which contains treatment and transfer sections (16, 17) and has suspension devices (14), the suspension devices (14 ) running on conveyor rails (31) to

Transport of even more than three meter long workpieces (12) suitable, with a drive mechanism (37, 38) connectable trolleys (13) and with their transfer sections (16) extend into at least one transfer area in which at least one mobile transfer trolley ( 25) is arranged such that it can move transversely to the Ford rails (31) and is designed to remove the suspension carriages (13), remove them or insert them into the conveyor rails (31)

Apparatus according to claim 1, characterized in that the hanging conveyors (14) are stretched straight and are arranged approximately parallel to one another and / or transfer sections (16) are provided at their two ends

Device according to claim 1 or 2, characterized in that the hanging conveyors 14 are arranged at different heights

Device according to one of the preceding claims, characterized in that the hanging conveyors (14) are designed for the lateral removal of the hanger carriages (13), for removal or for lateral insertion into the conveyor rails (31) 5. Device according to one of the preceding claims, characterized ^"in that the drive mechanism (37, 38) for the suspension carriage (13) towing device (37, 38), in particular oscillating chain or rope conveyor with only in the towing latching pawls ( 42), preferably separate, partially overlapping drives (37, 38) are provided in the treatment (17) and transfer sections (16), which can be controlled independently of one another.

6. Device according to one of the preceding claims, characterized in that the drive mechanism (38), in particular in the transfer section (16), is designed as a push rod drive (38a), preferably a drag pawl (42) which only engages in the towing direction End region of the movement of the push rod (77) is forcibly movable into an out-of-engagement position.

7. Device according to one of the preceding claims, characterized in that the drive mechanism, in particular in the treatment section (17), is designed as a toothed wheel / rack and pinion drive (37a), preferably the rack (80) on the suspension carriage (13) is arranged and / or the gear wheel (79) is provided with a freewheel and / or is arranged to be movable at least transversely to its axis (91) for engagement self-adaptation.

Device according to one of the preceding claims, characterized in that the suspension carriage (13), to which the workpieces (12) can be attached, runs in a conveyor rail (31) which forms the longitudinal guide and is preferably in the form of a prismatic rail have wheels (32) which can be lifted out and are mounted on carrying brackets (34)

Device according to one of the preceding claims, characterized in that numerous wheels (32) are arranged substantially uniformly distributed over the entire length of the suspension carriage (13). Device according to Claim 9, characterized in that the wheels (32) are arranged in separate groups

Device according to Claim 10, characterized in that the groups are each articulated on the hanger carriage (13)

Device according to one of the preceding claims, characterized in that the towing devices (37, 38) in treatment and transfer sections (17, 16) run on two different levels, the towing device (38) in the transfer section (16) with strands arranged one above the other the Ford rail (31) and the

Towing device (37) in the treatment section (17) runs alongside one another above the Ford rail (31), its guides securing the trolleys (13) in the treatment section (17) against lifting

Device according to one of the preceding claims, characterized in that the transfer carriage (25), in the manner of a ground-based lifting carriage, is arranged on a track arranged in the transfer section (16) on the floor (69), driving it and possibly securing it against lifting is, preferably in at least one rail (26), optionally covered with a toothed belt (70)

Device according to one of claims 1 to 12, characterized in that the converter carriage (25) can be moved in at least one rail (26) which is arranged at a distance from the floor (69) and at least one rail (26) in regions (92) is interrupted

Device according to Claim 14, characterized in that the transfer carriage (25) has at least 3 running wheels (54) at least on the side of the interrupted rail (26), each of which has a greater distance (94) from one another than the width (95) of the interrupted area (92) of the rail (26) 16. Device according to one of the preceding claims, characterized in that the transfer carriage (25) has height-movable, preferably laterally foldable arms (61) on which receptacles (62) for one or more suspension carriages (13) are provided, the Interacting recordings (62) and suspension trolleys (13) in particular self-centering, possibly by means of a V-shaped receptacle (62) and an adapted one

T-profile (33) on the trolley (13).

17. The apparatus according to Anspmch 16, characterized in that the arms (61) of the converting carriage (25) can be moved into the following positions: - an upper lifting position in which at least one suspension carriage (13) can be moved out of the

Conveyor rail (31) is lifted (Fig. 16), a hanging position in which the hanger carriage (13) is suspended in the conveyor rail (31) (Fig. 17), a transverse transport position in which the transfer carriage (25) a possibly can move the loaded trolley (13) under the overhead conveyors (14) transversely

(Fig. 14) and possibly an underride position in which the transfer carriage (25) loaded, hanging on the conveyor rails (31) hanging carriage (13) and workpieces (12) hanging thereon can pass under (Fig. 19), and - if necessary, a retracted position in which the arms (61) are in a substantially in

Lifting carriers (57) of the transfer carriage (25) which extend in the direction of the conveyor rails (31) are arranged in order to carry out a vertical movement also between conveyor rails (31) arranged closely next to one another.

18. Device according to one of the preceding claims, characterized in that the transfer carriage (25) has a chassis (51), laterally projecting columns (55), ei¬ NEN vertically movable on these columns (55), extending between these lifting beams ( 57) and arms (61) hinged to it, if necessary. 19 Device according to one of the preceding claims, characterized in that treatment devices (89) are provided in the transfer sections (16) into which the transfer carriages (25) workpieces (12) can move

20 Device according to one of the preceding claims, characterized by a common electronic control of a plurality of functional units (15) with a programmable control device (48) which controls the suspension devices (14), the at least one transfer carriage (25) with driving Controls, lifting and, if necessary, folding movements depending on sensor signals and, if necessary, an optical monitoring system to avoid collisions as well as a detection system for target identification on the hanger carriage

(13)

21 Device according to one of the preceding claims, characterized in that a plurality of parallel Ford rails (31) are provided in a functional unit (15)

22 Device according to Anspmch 21, characterized in that in the presence of several Hangefbrderem (14) arranged in a functional unit (15), individual da¬ are arranged laterally displaceable

23 Device according to Anspmch 22, characterized in that a common towing device (37, 38) is provided for a plurality of Ford rails (31), the hanger carriages (13) preferably being coupled to one another by lateral driver arms (65, 87) which may be connected by a Allow a dead center for a mutual drag offset

24. Functional unit for a device for surface treatment, in particular for powder coating, of workpieces (12), in particular according to one of the preceding claims, characterized by a modular structure, the functional unit (15) with other functional units (15) in a modular manner to form a device (11) can be assembled and can be coupled to one another via at least one transfer carriage (25).

25. Functional unit according to Anspmch 24, characterized in that the functional units (15) are floor-supported.