EP1746068B1 - Lift station in a surface treatment plant. - Google Patents

Abstract

The station has a stationary support structure (12) and a vertically displaceable lifting slide (22) that is supported on the support structure (12) and is arranged on a conveyer system (38). An electrical sliding contact (48) and two opposing contacts (52, 58) transmit electrical energy to the conveyer system only in a selected lifting position of the lifting slide (22). A lower and upper dead center of the slide pertains to the selected position. Energy storage is arranged on the slide to store the energy transmitted by the contacts. An independent claim is also included for a surface treatment plant comprising a lifting station.

Description

The invention relates to a lifting station for vertically moving an object, in particular a vehicle body, in a surface treatment system, comprising a stationary support structure and a vertically movable lifting carriage, which is supported on the support structure and is arranged on the at least one conveyor.

Surface treatment equipment serves to provide surfaces of articles in different ways, e.g. by applying paints and other coatings. Frequently such plants contain several individual treatment stations for different treatment steps, e.g. Prepare, varnish and dry. The objects to be treated, which may be, for example, motor vehicle bodies or other sheet metal parts, are conveyed for this purpose by means of a conveyor system from treatment station to treatment station.

For the surface treatment plant, such areas between and after the treatment stations are also counted here in which the articles to be treated are merely conveyed, stored or sorted. The promotion, storage and sorting of the objects to be treated is often done in several levels one above the other. In these cases, there is a need to implement the objects vertically between different levels.

Vertical conversion is also required when, for some reason, individual stations of the surface treatment facility are located at different levels relative to other stations. If the objects in a station are to be treated, for example, with gases which are heavier than a surrounding atmosphere, then such a treatment is often carried out in a lowered area, for example a kind of well, so that as few gases as possible are introduced through the inlet and outlet openings of the area escape. For a lighter gas or hot air treatment, for the same reasons, it is better to place the treatment area higher.

Known in the art lifting stations, which are provided for the vertical transfer of objects in surface treatment plants, have a lifting, which is guided by means of guide rollers in the vertical direction (stroke direction). This means that the lifting can move only in the vertical direction, in the directions perpendicular thereto, however, is fixed to a support structure. On the lifting a conveyor is arranged, which may be, for example, a roller conveyor or a chain conveyor. The conveyor makes it possible the objects from an upstream conveyor system on the lifting and from there - after the vertical transfer - to be transferred to a downstream conveyor system. In the place of the conveyor systems, of course, other feeding devices such as forklifts or similar. to step.

The conveyor requires energy during its operation during these transfer operations. In known lifting stations of the lifting carriage is therefore connected via a trailing cable with an external power supply.

The publication WO 2005/002998 A1 discloses a lifting station according to the preamble of claim 1.

However, it has been found that such trailing cables are disadvantageous in practice for various reasons. In order to prevent the trailing cable in the process of lifting the most or less unprotected surfaces of the objects touched or squeezed between moving parts of the lifting station, a guide structure with several moving parts is generally required, which movements of the trailing cable to a predetermined Limited space. In particular, in lifting stations, which can overcome greater heights, such guide structures can be quite expensive. In addition, tow cables that tolerate high bending stresses over long periods of time are quite expensive. If the lifting station with the lifting carriage is located in a warm area, eg before or after a dryer, the trailing cables are heavily stressed not only by the movement, but also by the ambient air, which may be over 200 ° C. Furthermore, dirt particles can accumulate on the trailing cables and their guide structures, which in the course of movement may again fall on freshly painted parts.

The object of the invention is therefore to improve a lifting station of the type mentioned in such a way that with the use of trailing cable related problems are at least partially avoided.

This object is achieved in a lifting station according to the preamble of claim 1 by an energy transfer device with which energy can be transferred to the conveyor only in at least one selected stroke position of the lifting.

The invention is based on the recognition that the conveyor in general anyway only in certain stroke positions of the lifting, which generally include the lower and upper dead center, is actuated. Therefore, it is sufficient to provide the conveyor with the help of an energy transfer device only energy available when this is actually needed. A trailing cable, which enables a power supply in all stroke positions, is then no longer required.

In the case of the energy which is transmitted to the conveyor with the aid of the energy transmission device, In principle, it can be any energy form which can be converted into the kinetic energy required by the conveyor. For example, electrical energy, mechanical energy or radiant energy may be considered.

Electrical energy is advantageous in that it can be used to transfer larger amounts of energy at selected stroke positions on the conveyor with inexpensive components. For example, the energy transfer device may comprise a stationary electrical contact and an electrical mating contact, which is arranged on the lifting carriage and in which cooperates at least one selected stroke position with the stationary contact.

If flammable gases or solids are present in the surroundings of the lifting station, then it may be better to use an energy transmission device which allows inductive transmission of electrical energy. In an inductive energy transfer, it can not practically come to the creation of sparks, as they often occur in electrical contacts, eg with loose contacts. A power transmission device based on the induction principle may comprise a first fixed induction loop and a second induction loop arranged on the lifting slide.

If energy is to be available on the lifting carriage even when it is not in the at least one selected lifting position, then it may be expedient to provide an energy store arranged on the lifting carriage, with which the energy transmitted via the energy transfer device is temporarily stored and stored, for example. can be passed to the conveyor. With such an energy storage, the conveyor can also be operated in lifting positions in which no energy transfer is possible. This energy can be used, for example, for control or measuring systems.

The energy store may be, for example, a pressure accumulator or a flywheel, if the energy is transmitted by mechanical means. In the case of transmission of electrical energy, the energy storage can be an accumulator.

An example of the transmission of mechanical energy by means of the energy transmission device is the supply of a pressurized gas that drives the conveyor via a docking station in a pneumatic manner.

However, it will be simplest in the transmission of mechanical energy, when the lifting station comprises a fixed drive unit and a clutch, with the kinetic energy from the drive unit to the conveyor can be transferred. The coupling may be, for example, a friction clutch, a toothed clutch or a magnetic clutch. The fixed drive unit can also be formed by a forward or downstream of the lifting station conveyor system.

Figur 1

eine Vorderansicht eines ersten Ausführungsbeispiels einer erfindungsgemäßen Hubstation, bei der Energie über elektrische Schleifkontakte übertragen wird, wobei sich ein Hubschlitten in einer unteren Hubposition befindet;

Figur 2

die in der Figur 1 gezeigte Hubstation, wobei sich der Hubschlitten in einer oberen Hubposition befindet;

Figur 3

eine Vorderansicht eines zweiten Ausführungsbeispiels einer erfindungsgemäßen Hubstation, bei der Energie induktiv übertragen wird, wobei sich ein Hubschlitten in einer unteren Hubposition befindet;

Figur 4

die in der Figur 3 gezeigte Hubstation, wobei sich der Hubschlitten in einer oberen Hubposition befindet;

Figur 5

eine Vorderansicht eines dritten Ausführungsbeispiels einer erfindungsgemäßen Hubstation, bei der Energie mechanisch über Reibrollen übertragen wird, wobei sich ein Hubschlitten in einer unteren Hubposition befindet;

Figur 6

die in der Figur 5 gezeigte Hubstation, wobei sich der Hubschlitten in einer oberen Hubposition befindet.

Further advantages and features of the invention will become apparent from the following description of exemplary embodiments with reference to the drawings. Show:

FIG. 1

a front view of a first embodiment of a lifting station according to the invention, in which energy is transmitted via electrical sliding contacts, wherein a lifting slide is in a lower stroke position;

FIG. 2

the in the FIG. 1 shown lifting station, wherein the lifting carriage is in an upper stroke position;

FIG. 3

a front view of a second embodiment of a lifting station according to the invention, in which energy is transmitted inductively, wherein a lifting slide is in a lower stroke position;

FIG. 4

the in the FIG. 3 shown lifting station, wherein the lifting carriage is in an upper stroke position;

FIG. 5

a front view of a third embodiment of a lifting station according to the invention, in which energy is transmitted mechanically via friction rollers, wherein a lifting slide is in a lower stroke position;

FIG. 6

the in the FIG. 5 shown lifting station, wherein the lifting carriage is in an upper stroke position.

The FIG. 1 shows a first embodiment of a total of 10 designated lifting station in a front view. The lifting station 10 has a support structure 12, which is composed of two vertical guide posts 14, 16 and these connecting crossbeams 18, 20. The guide posts 14, 16 and the transverse members 18, 20 can be made, for example, from steel profiles with a rectangular or round cross-section.

On the support structure 12, a lifting carriage 22 is supported in a manner not shown on several guide rollers. The guide rollers rest on the guide posts 14, 16 from several sides and ensure that the lifting carriage 22 can move freely in the vertical direction, while it is fixed perpendicular to the support structure 12.

On the lifting 22 engage two steel cables 24, 26, which are mounted on the upper cross-beam 18 pulleys 28, 30 guided down and there on cable drums 32, 34 are rolled up. The cable drums 32, 34 can be rotated by means of a drive motor 36 in rotation, whereby the lifting slide 22 is lowered or raised depending on the direction of rotation of the cable drums 32, 34.

On pointing in the direction of the viewer support arms of the lifting carriage 22, a roller conveyor 38 is fixed, can be promoted with the vertically umzusetzende objects along the longitudinal direction of the transverse members 18, 20. The roller conveyor 38 comprises for this purpose a plurality of rollers 40, which are connected via an only partially and dashed lines shown for reasons of clarity chain 42 with an electric roller drive 44. Of course, instead of a chain 42, a toothed belt or similar can also be used. be used. The roller drive 44 is connected via a line 46 with sliding contacts, which is attached to an end face of the roller conveyor 38. The number of sliding contacts required depends on the selected voltage supply (eg direct current or three-phase current). In the FIG. 1 For the sake of clarity, only one sliding contact is shown and designated 48.

In the FIG. 1 It can also be seen a part of a lower conveyor system 50, which is also designed as a roller conveyor. On the lower conveyor system 50, a first mating contact 52 is attached, which via a feed line 54 with one in the FIG. 1 not shown voltage source is connected, which is controlled by a total control, also not shown.

Top right in the FIG. 1 an upper conveyor system 56 is indicated, which is also designed as a roller conveyor. For example, the upper conveyor system 56 may lead to a drying area where painted articles are dried.

On the opposite side of the roller conveyor 38 is at the height of the upper conveyor system 56, a second mating contact 58 on a stationary support assembly 60, which may be, for example, a surrounding steel construction attached. The second mating contact 58 is also connected via a further supply line 62 to the controllable power supply.

In the following, the function of the above-described lifting station 10 with reference to the FIGS. 1 and 2 explained.

Let it be assumed that the object to be vertically transposed is a painted motor vehicle body, which in the FIG. 1 indicated by dashed lines 64 and attached to a designated as Skid 66 carrier. The vehicle body 64 is to be vertically transferred from the lower conveyor system 50 to the upper conveyor system 56 by means of the lifting station 10 to the To transfer vehicle body 64 in a drying area through which the upper conveyor system 56 extends.

First, the overall control ensures that the lifting slide 22 is transferred to its lower lifting position, in which the roller conveyor 38 is at the same height as the lower conveyor system 50. When lowering the lifting carriage 22, the sliding contact 48 comes into contact with the first mating contact 52, which is attached to the lower conveyor system 50. As soon as the contact is established, the higher-level control device switches on the power supply. Via the supply line 54, a current can now flow via the contacts 48, 52 to the roller drive 44. This drives via the chain 42, the rollers 40. The motor vehicle body 64 can now be transferred via the lower conveyor system 50 to the roller conveyor 38. If required, control information can also be transmitted via the now closed circuit, as is known per se in the prior art in connection with trailing cables.

As soon as the skid 66 is conveyed exclusively by the rollers 40 of the roller conveyor 38, the overall control causes a continuous reduction of the electrical voltage which can be tapped off at the mating contact 52. In this way, the rollers 40 and thus also the guided thereon Skid 66 are brought to a standstill. This condition is in the FIG. 1 shown.

The overall control now causes the drive motor 36 to lift the lift carriage 22 with the vehicle body 64 disposed thereon until the upper lift position is reached. When approaching the upper stroke position of the sliding contact 48 comes into contact with the second mating contact 58 which is fixed to the support assembly 60. After the lifting carriage 22 has reached its upper stroke position, a continuously increasing voltage is applied to the supply line 62, whereby a current flows through the contacts 48, 58 and the line 46. The roller drive 44 now sets the rollers 40 in motion, whereby the skid 66 is moved with the body 64 mounted thereon to the upper conveyor system 56 out. Its rollers finally take over the skid 66 and transfer the motor vehicle body 64 into the subsequent drying area. The state during the transfer of the vehicle body 64 to the upper conveyor system 56 is in the FIG. 2 shown.

The Figures 3 and 4 show a further embodiment of a lifting station in the FIGS. 1 and 2 ajar representations. The same or corresponding parts are provided with the same reference numerals.

In the in the Figures 3 and 4 shown and generally designated 210 lifting station, the energy for driving the roller drive 44 is not transmitted via electrical contacts, but inductively on the lifting carriage 22. For this purpose, a first induction coil 68 is attached to the lifting carriage 22, which can cooperate in the upper and the lower lifting position with second induction coils 70 and 72, respectively. By applying an alternating electric field to the two second induction coils 70, 72, a current can be induced by induction in the first induction coil 68, with which the electric roller drive 44 can be fed. The induction only occurs when the first induction coil 68 is located directly opposite one of the two second induction coils 70, 72.

The roller conveyor 38 of the lifting station 210 additionally contains an accumulator 73, which is connected between the first induction coil 68 and the roller drive 44. The accumulator 73, which is charged in the upper and lower lifting position, in the illustrated embodiment, the roller drive 44 and additional control or measuring systems, even with electrical energy supply, even if the lifting 22 in both the upper and in the lower stroke position located. The accumulator 73 can also be switched so that it supplies only such additional systems on the lifting carriage 22 position independent with electrical energy, while the energy required for the roller drive 44 is always provided directly from the first induction coil 68.

The function of in the Figures 3 and 4 Lifting station 210 shown otherwise corresponds to those of the lifting station 10, as described above with respect to the FIGS. 1 and 2 was explained.

The Figures 5 and 6 show a third embodiment of a lifting station also in the FIGS. 1 and 2 ajar representations. Same or corresponding parts are also here with the same reference numerals as in the FIGS. 1 and 2 referred to the first embodiment shown.

The chain 42, shown here in full, which drives the rollers 40 of the roller conveyor 38, is guided by gears 74, 76, which, however, are not connected to a motor drive. Instead, that is in the FIG. 5 Links recognizable gear 74 connected via a toothed gear with a friction wheel 78 which extends beyond the rear end face of the roller conveyor 38 slightly.

Mounted near the lower conveyor system 50 is a drive friction wheel 80 which is controllably driven by an electric motor 82 and cooperates with the friction wheel 78 when the lift carriage 22 is in the lower lift position. Another drive friction wheel 86, which may be driven by an electric motor 88, is attached to the support assembly 60.

Is the lifting slide 22 in one of the in the Figures 5 and 6 illustrated stroke positions, the friction wheel 78 of the roller conveyor 38 is frictionally engaged on one of the drive wheels 80 or 84 at. The associated motor 82 or 86 may then rotate, via appropriate drive friction wheels 80, 84, the friction wheel 78 and the gears 74, 76, to rotate the rollers 40 of the roller track 38 to convey the article on the roller track 38.

The task of the motors 82, 86 can also be taken over by the conveyor systems 50 and 56, respectively. The Antriebsreibräder 80, 84 are in this case only to be coupled to the drive for the conveyor systems 50 and 56 in a suitable manner. The rollers 40 of the roller conveyor 38 then move in the corresponding stroke position at the same speed as the rollers of the upstream and downstream conveyor system. It is also possible to provide a separate drive in a stroke position and to use the drive of the adjacent conveyor system in the other stroke position. In this way you may u.U. as a coupling only a friction wheel 78 on the roller conveyor 38th

Claims (15)

1. Lifting station for vertically moving an object in a surface treatment installation, comprising a fixed support structure (12) and a vertically movable lifting cradle (22) which is supported on the support structure (12) and on which at least one conveying device (38) is arranged,
   characterised by
   an energy transfer device (48, 52, 58; 68, 70, 72; 78, 80, 84) with which energy can be transferred to the conveying device (38) only in at least one selected lifting position of the lifting cradle (22).
2. Lifting station according to claim 1, characterised in that the at least one selected lifting positions include a lower and an upper dead centre position of the lifting cradle (22).
3. Lifting station according to claim 1 or 2, characterised in that the energy is electrical energy.
4. Lifting station according to claim 3, characterised in that the energy transfer device includes a fixed electrical contact (52, 58) and an electrical counter-contact (48) which is arranged on the lifting cradle (22) and cooperates with the fixed contact (52, 58) in the at least one selected lifting position.
5. Lifting station according to claim 3, characterised in that the energy transfer device (68, 70, 72) makes possible inductive transfer of electrical energy.
6. Lifting station according to claim 5, characterised in that the energy transfer device includes a first, fixed induction loop (70, 72) and a second induction loop (68) arranged on the lifting cradle (22).
7. Lifting station according to any one of the preceding claims, characterised by an energy accumulator (73) arranged on the lifting cradle (22), with which energy accumulator (73) energy transferred via the energy transfer device (48, 52, 58; 68, 70, 72; 78, 80, 84) can be temporarily stored.
8. Lifting station according to claim 7, characterised in that the energy accumulator is a storage battery (73).
9. Lifting station according to claim 1 or 2, characterised in that the energy is mechanical energy.
10. Lifting station according to claim 9, characterised in that it includes a fixed drive unit (82, 86) and a coupling (78, 80, 84) with which kinetic energy can be transmitted from the drive unit to the conveying device (38).
11. Lifting station according to claim 10, characterised in that the coupling (78, 80, 84) is a friction clutch.
12. Lifting station according to claim 10, characterised in that the coupling is a magnetic clutch.
13. Lifting station according to claim 10, characterised in that the coupling is a toothed clutch.
14. Lifting station according to any one of the preceding claims, characterised in that the conveying device is a roller conveyor (38) or a chain conveyor.
15. Surface treatment installation having a lifting station according to any one of claims 10 to 13, characterised in that the fixed drive unit is formed by a conveyor system located before or after the lifting station.

Images