Patent Application
20210001363
The invention concerns a method for through-type coating of a device that may rotate, preferably rotates, during coating according to the preamble of claim 1, a coating installation for performing such a method according to the preamble of claim 7 and a coating installation system comprising such coating installation according to the preamble of claim 12.
The known installations for through-type coating have a conveyor that extends through the coating booth, from the outside of the loading opening to the outside of the unloading opening. The conveyor must be protected against overspray or other contamination from coating. For that purpose, usually several movable or fixed masks or covers are used in order to shield the surface of the conveyor from this overspray. The masks or covers often have a rather complicated continue and they rather often leave slots through which the overspray can deposit on the surface of the conveyor, so that a complete shielding is not always guaranteed.
The problem becomes even worse if the devices to be coated have to rotate during coating. In this case the frames rotatably holding and driving the devices to be coated have to be moved along with the devices on the conveyor through the coating booth. That leads to an excessive shielding and cleaning effort.
Contamination of carriers and framework may lead to transfer and deposit of coating material into machine section arranged downstream of the machine structure. Such contamination and transfer reduces the quality of the coating. Another problem is that the air flow is obstructed by the conveyor and mask (or covers) which extends through the coating booth.
It is an object of the invention to provide for a method for performing a through-type coating which requires no or less shielding of parts that are not allowed to be coated.
The method described by the independent method claim provides a solution for that issue.
The inventive method is a method for through-type coating of a device that may rotate, preferably rotates, during coating—preferably around itself—in a closed coating booth and that is conveyed to and away from the coating booth by means of a carrier which is holding the device in a defined position. Under rotation similar movements to rotation can be understood as that the device is rotated swiveled or presented in a multi position way during coating. Preferably the device does not only but also rotate.
The method consists of or comprises at least the following steps:
The loaded carrier is picked off from a supplying conveyor. The supplying conveyor is preferably a belt conveyor or chain conveyer or any conveyor designed for to transfer devices sitting on a carrier. The carrier, loaded with at least one and preferably a multiplicity of devices to be coated, is moved together with the forks of a fork-type loader through a loading opening of a painting booth into this painting booth.
Such a device to be coated is normally a holder that holds itself a single or a number of substrates to be coated.
Arrived in the painting booth, the device to be coated is coupled to a system providing the device in appropriate manner during coating, preferably the device is rotated. Synchronously with coupling—or at the latest directly hereinafter—, the device to be coated is separated from its carrier, preferably by lowering the fork-type loader. Advantageously the fork-type loader of the invention comprises a very compact mechanism.
The carrier, which is now unloaded, is preferably lowered further over to the forks of a second fork-type unloader that extends through the unloading opening into the painting booth. In this action the carrier is preferably handed over from the fork-type loader to the fork-type unloader.
With other words, the forks of the loader and of the unloader extend through different openings of the booth into the interior of the booth.
Next, the empty forks of the loader are completely withdrawn out of the booth through the loading opening of the booth. Also, and preferred at least partially at the same time, the forks of the unloader are completely withdrawn out of the booth through the unloading opening of the booth. Over that, the independent actuated compact-loaders integrating the special arrangement of the forks will be able to pull out the one empty carrier off the spray booth while the other one is getting prepared to take over a new carrier with uncoated devices. Preferably an independent working with parallel processes is possible. Preferably the independent working is done in parallel processes.
The loading and the unloading opening of the booth are closed by means of shutters. The device to be coated is already rotating or starts rotating during or after the closing of the shutters. Now, the coating starts. After the coating is done and rotation has come to an end, at least the unloading opening of the booth is opened again.
The unloaded carrier is moved together with the forks of the unloader through an unloading opening of the painting booth into the painting booth. Now the coated device is coupled off from the system that has rotated the device during coating and synchronously or right after the coated device is joined with the carrier so that it can be moved together with the carrier.
The forks of the unloader are withdrawn together with the loaded carrier out of the booth through the unloading opening of the booth and the loaded carrier is handed over to a discharging conveyor.
The inventive method does not require any longer that a conveyor belt or a conveyor chain or any transfer element, such as for example cable conveyor technology, lifting beam conveyor technology, linear pushers etc., needs to be extended through the coating booth during coating. So the complicated shielding of the conveyor against overspray is not necessary anymore and no periodical cleaning of the conveyor from overspray that has deposited on the conveyor despite the masking is necessary anymore. Moreover, there is no necessity anymore that the carrier stays positioned in the coating booth during coating.
An important advantage is that nevertheless, the carriers are transported through the coating booth in order to take up the devices after coating again. That way, it is not necessary anymore to collect and to send back again the carriers in front of the coating booth and it is not necessary anymore to continuously make available “fresh” carriers right after the coating booth. Advantageously it is not required that any part of the conveyor system is placed in the coating booth.
It is preferred to operate the forks in a way that the forks of the loader and the unloader, coming from opposite sides each, meet and laterally pass (or mesh) each other underneath the carrier for handover of the carrier. Thus, it is very easy to accomplish the handover of the carrier from one fork to the other by means of moving at least the fork of the loader relatively to the other fork of the unloader in vertical direction. Thereby, only one of the forks moves while the other stand still or preferably both forks move in opposite vertical directions.
The carrier is moved by means of the forks across through the coating booth as long as no coating takes place.
Preferably, the method is carried out so that the forks of the loader and of the unloader carry out a synchronous transversal movement during loading and/or unloading of the booth. With other words: In order to save time it is advantageous, for example, if during the withdrawal of the unloader's fork having picked up the carrier and the coated device(s) already the loaders fork having picked up a new carrier and the device(s) to be coated next moves into the coating booth.
Preferably, the coupling of the device to the system rotating the device during coating and the separation of the device from its carrier is accomplished by coupling to the ends of the device and then lowering the carrier. For that purpose the fork actually carrying the carrier moves in vertical downward direction. The uncoupling of the device to the system having rotated the device during coating and the fixing of the device to its carrier for further transportation preferably takes place in opposite direction.
For sake of completeness it has to be noticed that obligatory or preferred features that have been by now expressed in terms of a method can lead to a corresponding physical design of the installation for performing this method.
Moreover, the invention results in a coating installation according to the first device claim.
The inventive coating installation is physically designed so that it is fit for performing the method as explained before.
The coating installation includes a coating booth with a loading opening and a separate unloading opening. Moreover, the coating installation comprises a rotating unit positioned in the booth. The device to be coated can be coupled to the rotating unit. That way, the device to be coated can rotate during coating, preferably around itself. Moreover the inventive coating installation comprises a fork-type loader with forks that can reach through the loading opening into the booth and a separate fork-type unloader with forks that can reach—in opposite direction—through the unloading opening into the booth.
According to the invention, the forks of the loader and of the unloader are—relative to one another—movable in such a way that an empty carrier can be handed over from the forks of the loader to the forks of the unloader within the interior of the coating booth itself. That way it becomes possible to move a carrier across the coating booth without a conveyor chain or belt being fixedly mounted in the booth for crossing it.
Preferably, the loader and the unloader have at least a fork each that is movable back and forth in horizontal direction and that is movable in vertical direction up and down. A very preferred solution is to design the forks in such a way that the arms of the respective fork are positioned laterally beside and below a belt-like or chain-like conveyor so that a carrier positioned by the conveyor above the forks can be lifted off from the conveyor by moving the forks in upward direction or so that a carrier can be deposited on the conveyor by moving the forks in downward direction in preferred embodiment passing the transportation surface of the carrier in that way.
Self expanding fork is part of the complete device providing the features to realize the course to be run for charging and discharging the coating booth with the afore mentioned devices. Integrating such functionality preferably allows to bridge the free span between the booth integrated rotation device and the gates of the booth. Such compact design preferably reduces the impact of machine design for the process to be run. Still getting the fork-loader-system integrated in a small booth protecting the process equipment and substrates is mainly protected against contamination as mentioned above.
Another preferred embodiment provides that the rotating system is designed so, that each device to be coated can be coupled and uncoupled to and from the rotating system by performing nothing else than a vertical movement. For that purpose, it is advantageous if the device to be coated is a spindle with two shaft stubs extending therefrom in opposite directions. A preferred embodiment of the rotating system comprises at least two pairs of rollers. Between the two opposite rollers of each pair a cone-shaped gap is embodied. By means of said cone-shaped gap the rollers of each pair can pick up said shaft stub between each other so that the shaft stub is forced to rotate along with the rollers. The cone-shaped gap can also be described as v-shaped gap. The expression “shaft stub” says nothing about the shaft length. It means a shaft that has one free end while the other end is fixed to the said spindle.
Preferably, the system rotating the device during coating is driven by at least one motor that is positioned outside of the booth. Said motor preferably drives a shaft that extends through a wall of the booth into the booth, whereas the breakthrough is preferably sealed. The end of said shaft protruding into the coating booth normally carries one of said rollers supporting the said shaft stub.
Moreover, the invention results in a coating installation according to the second independent device claim.
The according coating installation system comprises a coating installation as explained before and, in addition, a multiplicity of carriers. Each carrier comprises at least two recesses into each of which a shaft stub can be inserted from above so that the spindle—from which the shaft stubs protrude—is held by the carrier, whereas the recesses are positioned and designed that way that the end portion of each shaft stub that is provided for being coupled with the said system rotating the spindle during coating freely protrudes from the corresponding recess in outward direction, so that the end of each shaft stub can be coupled to the rotating system.
Further options for design, further technical effects and further benefits are taught by the following example for an inventive embodiment that is explained in greater detail by means of the figures illustrating this embodiment.
As it can be seen, in
An important aspect is that the coating booth 6 can be completely closed during coating so that no or no relevant amount of solvents, overspray and/or dust or other emissions can escape the coating booth. For that purpose, shutters are provided with which the loading opening 7 and the unloading opening 8 can be closed.
Right in front of the loading opening a loader 4 is positioned. The loader 4 is normally of the fork-lift type. That means loader 4 possesses at least two arms that together form a loading fork which can perform a translatory movement back and forth so that the arms are at least almost completely within the coating booth 6 or completely out of the coating booth. In addition, at least two arms can be moved in vertical direction up and down.
For that purpose, in most cases, the two arms are guided together in a translatory fashion along a common frame, whereas the common frame as a whole can be moved up and down.
As it will be shown in more detail later, it is preferred to design the loading in that way, that one arm can be positioned laterally below the belt or chain of supplying conveyor 2 while the other arm can be positioned laterally below the belt or chain of the supplying conveyor on the other side. Thus, the belt or chain of the supplying conveyor can position a carrier with a device to be coated above the forks of the loader. That way the loader has a possibility to pick up a carrier with a device to be coated from the belt or chain of the supplying conveyor 2.
Right behind the unloading opening 8 an unloader 10 is positioned. The unloader 5 is normally of the fork-lift type, too. All the details that have been described in regard to the design of the loader 4 may apply analogously to the unloader 5. In particular, the at least two arms of the unloader 5 can be moved into a position laterally and below the belt or chain of the discharge conveyor 3 so that a carrier 11 with the coated device can be handed over by the unloader 5 the discharge conveyor by positioning it on the top of the belt or chain.
An important aspect is that the arms of the loader 4 and the arms of the unloaders 5 are positioned with the necessary offset. That means that the arms of the loader 4 and the unloader 5 can pass each other when the arms of the loader move through the loading opening into the paint booth 6 while the arms of the unloader are moved through the unloading opening into the paint booth 6. The situation is shown by
For the sake of completeness it has to be said that the arms forming together the loading fork 44 and the unloading fork 55 are preferably designed that way that they are telescoping. There is for example the possibility that arms are realised, each by a plunger of a pneumatic cylinder or telescopic rails driven by a electrical motor.
Looking at
This visualises that it is rather easy to bring the spindle by means of the carrier 11 in a position where the carrier is not required anymore because the spindle is sole and only held by the rotating system, so that the carrier can be removed out of the coating booth 6.
As roughly sketched by
The following sequence of the
The loader 4 has already picked up or is about, preferably on train, to pick up a carrier 11 which carries preferably two or more devices to be coated 12 and which are waiting for coating. The unloader 5 holds an empty carrier 11 in wait state.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/053445 | 2/12/2019 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62629199 | Feb 2018 | US |
