Multi-color powder center for supplying at least one powder spraying device with different types of coating powder as required

Description

[0001] The invention relates to a multi-color powder center for supplying at least one powder spraying device with coating powder of different types as needed. See WO00 / 29124.

[0002] The multi-color powder center according to the invention is particularly suitable for supplying powder to powder spraying devices used for the electrostatic spray coating of objects with powder. Fresh coating powder (also referred to herein as "fresh powder") and optionally recovered coating powder (also referred to herein as "recovery powder") are located in powder containers and are supplied to one or more spraying devices or powder spraying devices by a pump unit with at least one powder pump, for example in the form of a powder injector or a dense-phase powder pump. The spraying devices / powder spraying devices can be, for example, manual guns or automatic guns.

[0003] The invention is based on the problem that powder coating systems and the associated powder supply devices must be carefully cleaned when changing powder (changing from one powder type to another powder type), and in particular when changing colors (changing from powder of a first color to powder with a different second color), since even a few powder particles of the previous powder type can result in coating defects when coating with the new powder type.

[0004] The invention is intended to solve the problem of creating a possibility by which a powder change can be carried out quickly and easily or by which a multi-colour spray coating can be carried out as efficiently as possible.

[0005] This object is achieved according to the invention by the features of independent patent claim 1. Advantageous developments of the multi-color powder center according to the invention are specified in the dependent patent claims.

[0006] Accordingly, in particular, a multi-color powder center is specified for supplying at least one powder spraying device with coating powder of a different type as needed, wherein the multi-color powder center has a first powder container for receiving coating powder of a first type and at least one second powder container for receiving coating powder of a second type. Furthermore, at least one powder dispensing device in the form of a pump unit with at least one powder pump, in particular a dense-phase powder pump or a dilute-phase powder pump, is provided. The pressure side of the powder pump is fluidly connected or connectable to the powder inlet of a powder spraying device, such as a manual gun or an automatic powder gun.

[0007] According to one aspect of the invention, it is particularly provided that the at least one pump unit and / or the powder containers are movable relative to one another in such a way that, if required, the suction side of the at least one powder pump is or can be connected in terms of flow either to the interior of the first powder container or to the interior of the at least one second powder container.

[0008] According to embodiments of the invention, for example, the pump unit is movable relative to the powder containers in such a way that, as required, the suction side of the at least one powder pump is or can be connected in terms of flow either to the interior of the first powder container or to the interior of the at least one second powder container.

[0009] Because the multi-color powder center according to the invention has at least one pump unit movable relative to the powder containers, powder changeover or multi-color spray coating operation is possible in an easy-to-implement and particularly effective manner. For this purpose, it is only necessary that the pump unit is transferred from a first powder container to a second powder container, so that the suction side of the pump unit can then be connected to the interior of the second powder container.

[0010] According to one aspect of the present invention, a cleaning station is further provided for cleaning the pump unit, a line system leading from the pump unit to at least one powder spray device, and / or at least one powder spray device as required. This cleaning as required takes place in particular when changing from a first powder type to a different second powder type. In this context, it is conceivable for the pump unit to be movable relative to the cleaning station in such a way that it can be cleaned in or at the cleaning station as required, and in particular rinsed with compressed cleaning air. Alternatively, it is conceivable for the cleaning station to be movable relative to the pump unit in such a way that the pump unit can be cleaned in or at the cleaning station as required, and in particular rinsed with compressed cleaning air.

[0011] According to embodiments of the multi-color powder center according to the invention, a drive is assigned to the cleaning station and / or the pump unit itself in order to be able to move the cleaning station relative to the pump unit in such a way that the pump unit can be cleaned in or at the cleaning station as needed and in particular can be rinsed with compressed cleaning air.

[0012] In preferred embodiments of the multi-color powder center according to the invention, a carriage or slide assembly is assigned to the at least one pump unit, by means of which the pump unit can be moved in a horizontal plane and above the powder containers, as well as guided relative to them. Alternatively or additionally, the pump unit can also be assigned a vertical guide unit for moving the pump unit or parts thereof vertically relative to the powder containers as needed.

[0013] According to embodiments of the multi-color powder center according to the invention, a drive, in particular a linear drive, is assigned to the first powder container and / or the at least one second powder container for moving the corresponding powder container relative to the pump unit as needed. In this context, it is particularly conceivable for the first powder container and the at least one second powder container to be movable independently of one another relative to the pump unit.

[0014] According to embodiments of the multi-color powder center according to the invention, the at least one pump unit has at least two powder pumps, in particular independently operable, which are arranged in the pump unit such that, in a state when the pump unit is coupled to a powder container or a cleaning station, the at least two powder pumps are each connected on the suction side to the interior of the powder container or the cleaning station.

[0015] For example, it is conceivable that a first and at least one further second pump unit are provided, each with at least one powder pump, in particular a dense phase or dilute phase powder pump, wherein the pump units are movable independently of one another relative to the powder containers in such a way that that, if required, the suction side of the at least one powder pump of the first pump unit and the suction side of the at least one powder pump of the at least one second pump unit are fluidly connected or connectable either to the interior of the first powder container or to the interior of the at least one second powder container; and / or that, if required, the suction side of the at least one powder pump of the first pump unit is fluidly connected or connectable to the interior of a first of the at least two powder containers and the suction side of the at least one powder pump of the second pump unit is fluidly connected or connectable to the interior of the other of the at least two powder containers.

[0016] In a further development of the last-mentioned embodiment of the multi-color powder center according to the invention, the first and at least one further second pump units are movable relative to one another and relative to the powder containers in at least one horizontal direction. Alternatively or additionally, it can be provided that the first and at least one second powder containers are movable relative to one another and relative to the first and at least one second pump units in at least one horizontal direction.

[0017] In a conceivable implementation of the multi-color powder center according to the invention, a plurality of powder containers arranged in a matrix relative to one another is provided, wherein the at least one pump unit is movable relative to the powder containers in a first horizontal direction and in a second horizontal direction orthogonal to the first horizontal direction such that, if required, the suction side of the at least one powder pump is or can be connected in terms of flow to the interior of a powder container of the plurality of powder containers.

[0018] Alternatively, a plurality of powder containers arranged in a matrix relative to one another can be provided, wherein the powder containers are movable relative to the at least one pump unit in a first horizontal direction and in a second horizontal direction orthogonal to the first horizontal direction such that, if required, the suction side of the at least one powder pump is or can be connected in terms of flow to the interior of a powder container of the plurality of powder containers.

[0019] Alternatively, a plurality of powder containers arranged in a matrix relative to one another can be provided, wherein the powder containers are movable in a first horizontal direction and the at least one pump unit is movable in a second horizontal direction orthogonal to the first horizontal direction such that, if required, the suction side of the at least one powder pump is or can be connected in terms of flow to the interior of a powder container of the plurality of powder containers.

[0020] According to a further aspect of the present disclosure, the pump unit comprises a docking unit, via which the suction side of the at least one powder pump can be fluidly connected to the interior of one of the powder containers, as needed. In this context, it is conceivable for the docking unit to be associated with a vertical guide unit, with which the docking unit can be moved vertically relative to the at least one powder pump of the pump unit and the powder containers, as needed.

[0021] The invention further relates to a multi-color powder center for supplying at least one powder spraying device with different types of coating powder as needed. The multi-color powder center has at least one powder container for receiving coating powder and a pump unit with at least one powder pump, in particular a dense-phase or dilute-phase powder pump, the pressure side of which is fluidly connected or connectable to the powder inlet of a powder spraying device. According to this aspect of the invention, the pump unit is assigned a docking unit, via which the suction side of the at least one powder pump can be fluidly connected to the interior of the powder container as needed.

[0022] Preferably, the docking unit is movable in the vertical direction relative to the pump unit and relative to the powder container as required for fluidly connecting or separating the suction side of the at least one powder pump with or from the interior of the powder container.

[0023] For example, the powder container can have at least one intake channel, preferably formed in an intake pipe, which has a suction opening opening into the interior of the powder container and an opposite discharge opening opening opening into a connection, wherein the suction side of the at least one powder pump can be fluidly connected to the connection of the powder container via the docking unit. In this context, it is conceivable for the connection to be arranged in an upper region and in particular in a lid region of the powder container, in such a way that the connection can be fluidly connected to the suction side of the at least one powder pump of the pump unit via the docking unit.

[0024] According to embodiments, the docking unit has a first connection associated with the suction side of the at least one pump unit and at least one second connection associated with the powder container. The first connection is fluidly connected to the second connection via a line section, and the line section is designed to be flexible such that the second connection is movable relative to the first connection over a predetermined distance. The predetermined distance corresponds, in particular, at least substantially to a vertical distance between the second connection of the docking unit and a connection of the powder container.

[0025] According to embodiments of the docking unit according to the invention, the second connection of the docking unit is designed to complement a connection of the powder container in such a way that it can be connected to the connection of the powder container in such a way that the at least one powder pump of the pump unit can be fluidly connected to a corresponding intake opening of a suction channel assigned to the powder container. For example, the second connection of the docking unit and / or the connection of the powder container are / is designed as a preferably self-closing hose coupling, in particular a bayonet coupling.

[0026] It is conceivable that a cleaning station is also provided for cleaning the at least one pump unit and / or a line system leading from the pump unit to at least one powder spray device and / or at least one powder spray device as needed, particularly when changing from a first powder type to a different second powder type. The docking unit assigned to the pump unit is preferably designed to fluidly connect the suction side of the at least one powder pump to a cleaning connection of the cleaning station as needed.

[0027] According to embodiments of the docking unit according to the invention, the docking unit and / or the at least one powder container are / are movable relative to each other, preferably in the vertical direction. In this context, it is advantageous if a vertical guide unit is assigned to the docking unit for moving the docking unit or parts thereof in the vertical direction as required.

[0028] The invention further relates to a multi-color powder center for supplying at least one powder spraying device with different types of coating powder as needed, wherein the multi-color powder center has at least one powder container for receiving coating powder and at least one pump unit with at least one powder pump, in particular a dense-phase or dilute-phase powder pump, the pressure side of which is or can be connected in terms of flow to the powder inlet of a powder spraying device. According to this aspect, it is particularly provided that the at least one powder container has at least one intake channel, preferably formed in an intake pipe, which has an intake opening opening into the interior of the powder container and an opposite discharge opening opening into a connection, wherein the intake side of the at least one powder pump can be connected in terms of flow to the connection of the powder container.

[0029] In this context, it is conceivable that the connection is arranged in an upper region and in particular in a lid region of the powder container, in such a way that the connection can be fluidly connected to the suction side of the at least one powder pump of the pump unit.

[0030] The at least one intake channel is formed in a dip tube projecting into the interior of the at least one powder container or in a side wall of the at least one powder container.

[0031] According to embodiments of the multi-color powder center according to the invention, the at least one powder container has a substantially cuboidal or cylindrical powder chamber for coating powder and a fluidizing device for introducing fluidizing compressed air into the powder chamber. At least one inlet opening leading into the interior of the powder container can be provided in a side wall or in a lid of the at least one powder container for supplying coating powder as needed during a powder coating operation of the multi-color powder center or optionally for introducing cleaning compressed air during a cleaning operation of the multi-color powder center or of the at least one powder container.

[0032] It is advantageous if at least one outlet leading out of the interior of the at least one powder container is provided for discharging fluidizing compressed air introduced into the powder chamber of the at least one powder container or optionally for discharging cleaning air introduced into the powder chamber during a cleaning operation, optionally together with residual powder transported by the cleaning compressed air.

[0033] The powder chamber of the at least one powder container preferably has at least one fluidizing compressed air outlet with an outlet opening for discharging the fluidizing compressed air introduced into the powder chamber. The fluidizing compressed air outlet can have a vent line, which is connected or connectable to a riser pipe outside the powder container to prevent powder discharge from the powder chamber of the at least one powder container in a powder coating operation of the multi-color powder center. In this context, it is conceivable for the at least one fluidizing compressed air outlet to have a vent line, which, on the one hand, is connected or connectable to the outlet opening of the fluidizing compressed air outlet and, on the other hand, opens into an extraction funnel of an extraction system, preferably designed as an air volume amplifier.

[0034] Preferably, at least one level sensor is also provided for detecting at least one powder level inside the at least one powder container. The at least one level sensor is, in particular, a contactless level sensor arranged outside the powder container, separate from the interior of the powder container.

[0035] The powder containers can be fixed, self-cleaning containers arranged in series, or individual, movable or mobile powder containers. In this context, it is particularly conceivable for the powder containers to be integrated into an automatic powder feed system, so that the powder containers can be fed with the appropriate coating powder automatically or optionally automatically as needed. The powder feed system can be designed, for example, as a paternoster system.

[0036] Each powder container can be equipped with the following functions: Level sensor for level monitoring and corresponding communication; fluidization or preconditioning of the powder when changing powder type so that the powder is conveyed immediately after docking; integration of a sieve; integration of a vibration unit; sensors for detecting the correct positioning of the powder container; code plate, barcode, RFID card, or the like for detecting and / or identifying the powder container or its contents; connection to a larger fresh powder container (e.g. big bag station) outside the multi-color center for automatic refilling of powder; and / or connection to a powder return system.

[0037] In this context, it is conceivable for a recovery powder return system to be assigned to the multi-color powder center for returning recovery powder to the first powder container and / or to the at least one second powder container as needed. The recovery powder return system can have at least one return line, in particular in the form of a return hose, which is or can be connected, in particular as needed, in terms of flow to a powder coating booth or coating workstation on the one hand and to the first powder container and / or to the at least one second powder container for returning recovery powder to the corresponding powder container. The at least one return line is preferably movable, in particular horizontally movable, on a carriage or slide arrangement relative to the first powder container and / or the at least one second powder container.

[0038] Furthermore, the at least one return line can be movable relative to the first powder container and / or the at least one second powder container, in particular vertically movable, in order to form a flow connection with the corresponding powder container.

[0039] According to embodiments, a powder container venting system is assigned to the multi-color powder center for venting the first powder container and / or the at least one second powder container as needed. The powder container venting system can have at least one venting line, in particular in the form of a venting hose, which is fluidly connected, in particular as needed or permanently, to the first powder container and / or the at least one second powder container for venting the corresponding powder container. Here, too, it is advantageous if the at least one venting line is movable, in particular horizontally movable, on a carriage or slide arrangement relative to the first powder container and / or the at least one second powder container.

[0040] The powder container size is preferably between 5 and 150 liters, depending on the container type.

[0041] Further powder supply devices such as devices for conveying directly from the powder box or powder barrel are conceivable.

[0042] According to embodiments of the powder containers used in the multi-color center according to the invention, these are each equipped with a vibrating sieve device for spray coating powder. The vibrating sieve device can comprise a sieve and a vibrator for vibrating the sieve. For example, the vibrator is designed as a compressed air vibrator or an ultrasonic sieve.

[0043] In a further development, at least one device for measuring the air pressure prevailing inside the at least one powder container is provided.

[0044] In this context, it is advantageous if: the quantity of fluidizing compressed air supplied to the at least one powder container per unit of time is preferably automatically adjustable depending on the air pressure prevailing inside the at least one powder container; and / or the quantity of cleaning compressed air supplied to the at least one powder container per unit of time is preferably automatically adjustable depending on the air pressure prevailing inside the at least one powder container; and / or the quantity of fluidizing compressed air discharged from the at least one powder container per unit of time is preferably automatically adjustable depending on the air pressure prevailing inside the at least one powder container; and / or the quantity of cleaning compressed air discharged via at least one residual powder outlet per unit of time is preferably automatically adjustable depending on the air pressure prevailing inside the at least one powder container.

[0045] In the following, exemplary embodiments of the solution according to the invention are described with reference to the accompanying drawings.

[0046] The drawings show: FIG. 1a schematically and in an isometric view a first exemplary embodiment of the multi-color powder center according to the invention; FIG. 1b schematically and in an isometric view a second exemplary embodiment of the multi-color powder center according to the invention; FIG. 2a schematically and in an isometric view a detailed view of a in the exemplary embodiment according to FIG. 1a used pump unit; FIG. 2b schematically and in an isometric view a detailed view of a pump unit used in the exemplary embodiment according to FIG. 1b used pump unit; FIG. 3a schematically and in an isometric view a further detailed view of a pump unit used in the exemplary embodiment according to FIG. 1a used pump unit; FIG. 3b schematically and in an isometric view a further detailed view of a pump unit used in the exemplary embodiment according to FIG. 1b used pump unit; FIG. 4 schematically and in a side view the pump unit according to FIG. 2b ; FIG. 5a-d schematically shows further exemplary embodiments of the multi-color powder center according to the invention; FIG. 6 schematically and in an isometric view a third exemplary embodiment of the multi-color powder center according to the invention (without powder container); and FIG. 7 schematically and in an isometric view a detailed view of a in the exemplary embodiment according to FIG. 6 pump unit used.

[0047] In FIG. 1a and FIG. 1b Exemplary embodiments of the multi-color powder center 1 according to the invention are shown schematically and in an isometric view.

[0048] In short, the exemplary embodiments of this multi-color powder center 1 each have a plurality (in the case of FIG. 1a The device comprises a plurality of (for example, eight) powder containers 2.1-2.8, which are designed to hold coating powders of different types. According to the illustrated embodiment, each of the plurality of powder containers 2.1-2.8 has a substantially cuboid-shaped powder chamber for holding the corresponding coating powder.

[0049] The structure of the exemplary embodiments of the multi-color powder center 1 according to the invention consists in detail of a frame 15 with several powder containers 2.1-2.8 arranged next to one another and a carriage (carriage / slide arrangement 6) moving above the powder containers 2.1-2.8, consisting of several powder pumps 4 (here: dense phase pumps) combined to form a pump unit 3.1-3.6 and a vertically moving docking unit 8 with a corresponding docking plate 9.

[0050] The powder containers 2.1-2.8 are typically filled with different types of powder. The powder containers 2.1-2.8 are designed to be removable from the container row. Guides and the like ensure that the position of the powder container is centered and indexed. All powder containers 2.1-2.8 are connected to a central suction device, which vents any excess pressure in the powder containers 2.1-2.8 caused by a fluidization process of the powder. In addition to its lid function, the lid 11 of each powder container 2.1-2.8 has integrated suction pipes with docking interfaces (connections 10) located at the upper end.

[0051] The driven and precisely positionable carriage (carriage / slide assembly 6) with the pump unit 3.1-3.6 and the docking unit 8 moves along a guide rail 16 and positions itself directly above a powder container 2.1-2.8. A vertical movement of the entire docking plate 9 of the docking unit 8 connects the intake sides of the powder pumps 4 with the intake pipes of the powder containers 2.1-2.8. The latter is preferably a self-centering construction.

[0052] Although not shown in the drawings, multiple powder spray guns can be connected simultaneously to the single powder container 2.1-2.8. The powder pumps 4 then start pumping the powder from the powder container 2.1-2.8 toward the guns.

[0053] When changing the powder (color change), the mechanism of the "old" powder container 2.1-2.8 is undocked, and the carriage (carriage / slide assembly 6) moves into a cleaning position, where several pneumatic valves clean the powder-carrying components (both toward the gun and the intake hose). The "new" powder container 2.1-2.8 is then moved to the new position.

[0054] The consistent powder feed quality is achieved with the advantages of a dense phase pump and its integration into the system with the shortest possible suction distances.

[0055] In FIG. 1a An example of a design with a total of eight powder containers 2.1-2.8 is shown. An application with fewer, up to only two, powder containers is also conceivable. For example, in FIG. 1b an embodiment with a total of four powder containers 2.1-2.4 is shown.

[0056] In particular, if there are more than ten powder containers, a second and further row can be set up parallel to the first row of containers (see FIG. 5d . In this case, the container rows are mounted on a separate support on the floor and the frame 15 with the carriage (carriage / slide arrangement 6) becomes a portal, ie it is equipped with an additional drive and moves in the X direction to the corresponding container row.

[0057] The FIG. 5a The variant shown schematically is according to the draft according to FIG. 1 , in which a pump unit 3.1 (or gun) uses a single powder type. This requires a (single) slide assembly 6.

[0058] The FIG. 5b The schematically shown variant allows for the formation of groups: a first group of pump units 3.1 or a first pump unit 3.1 uses one type of powder, and another group of pump units 3.2 or a further pump unit 3.2 simultaneously uses a different or the same type of powder. In this example, two carriage arrangements 6 are required for this purpose. The practical application behind this is, for example, supplying two booth spray stations with a multi-color powder center 1.

[0059] At the FIG. 5c In the schematically shown variant, each individual pump unit 3.1-3.6 (or gun) can be assigned to an individual powder type. This requires a carriage assembly 6 for each pump unit 3.1-3.6. In practical applications, manual guns are typically used for coating very small quantities (e.g., individual metal furniture parts that are processed according to the FIFO principle and therefore have different color requirements).

[0060] For a large number of powder containers 2.1-2.12 or powder types, the FIG. 5d schematically shown, the complete pump unit 3.1 can also be moved to another row of powder containers.

[0061] Although not shown in the drawings, at least one cleaning compressed air inlet can be provided in a side wall of each powder container 2.1-2.12, to which a compressed air source can be connected via a compressed air line during a cleaning operation of the powder container 2.1-2.12 to remove residual powder from the corresponding powder chamber in order to introduce cleaning compressed air into the powder chamber. Furthermore, it is conceivable that a residual powder outlet is provided on the aforementioned side wall or bottom of the corresponding powder container 2.1-2.12, which has an outlet opening through which residual powder can be expelled from the powder chamber with the aid of the cleaning compressed air introduced into the powder chamber during the cleaning operation of the powder container 2.1-2.12.

[0062] The respective powder containers 2.1-2.12 of the exemplary embodiment of the multi-color powder center 1 according to the invention shown in the drawings preferably also have an inlet opening for the on-demand supply of fresh powder and / or recovery powder. Of course, it is also conceivable in this context to provide a separate powder inlet for fresh powder and recovery powder.

[0063] Preferably, the respective powder containers 2.1-2.12 of the exemplary embodiment of the multi-color powder center 1 according to the invention are each assigned a fluidizing device for introducing fluidizing compressed air into the corresponding powder chamber. The fluidizing compressed air can be introduced into the corresponding powder chamber through an end wall, a side longitudinal wall, a bottom wall, or a top wall. In particular, it is advisable to design the bottom wall of the corresponding powder chamber as a fluidizing bottom. The fluidizing bottom should have a plurality of open pores or small through-openings through which fluidizing compressed air can flow upwards from a fluidizing compressed air chamber arranged below the bottom wall into the corresponding powder chamber in order to place the coating powder therein into a suspended state during powder coating operation of the multi-color powder center 1 (i.e.(to fluidize) so that it can be easily extracted using a powder dispensing device in the form of a pump unit 3.1-3.6. The fluidizing compressed air is supplied to the fluidizing compressed air chamber through a fluidizing compressed air inlet.

[0064] To ensure that the pressure within the corresponding powder chamber does not exceed a predetermined or definable maximum pressure during operation of the fluidizing device, each powder chamber of the multi-color powder center 1 has at least one fluidizing compressed air outlet with an outlet opening for discharging the fluidizing compressed air introduced into the powder chamber and for achieving pressure equalization. In particular, the outlet opening of the at least one fluidizing compressed air outlet of each powder chamber of the plurality of powder containers 2.1-2.12 should be dimensioned such that, during operation of the fluidizing device, a maximum overpressure of 0.5 bar prevails in the corresponding powder chamber compared to atmospheric pressure.

[0065] A valve or the like can also be attached to the outlet opening to vent only the powder containers under fluidization pressure.

[0066] To discharge the fluidizing compressed air introduced into the respective powder chambers of the powder containers 2.1-2.12, a central vent line connecting the powder chambers is preferably provided, which leads to a central extraction system.

[0067] At the FIG. 1a In the schematically illustrated exemplary embodiment, each powder container 2.1-2.8 has a preferably contactless level sensor 17 for detecting the maximum permissible powder level in the corresponding powder chamber. It is conceivable to provide a further level sensor 17, which is arranged with respect to the powder container 2.1-2.12 in such a way as to detect a minimum powder level and, as soon as this minimum powder level is reached or undershot, to send a corresponding message to a control unit in order to preferably automatically supply fresh powder or recovery powder to the corresponding powder chamber via an inlet opening.

[0068] Preferably, the level sensor 17 for detecting the powder level in the corresponding powder chamber is a non-contact level sensor 17 and is arranged outside the powder chamber, separate from it. This prevents contamination of the level sensor 17. The level sensor 17 generates a signal when the powder level has reached a certain height. Several such powder level sensors can also be arranged at different heights, for example, for detecting predetermined maximum levels and for detecting a predetermined minimum level.

[0069] The signals of the at least one level sensor 17 are preferably used to control an automatic powder feed of coating powder through corresponding powder inlets into the corresponding powder chambers in order to maintain a predetermined level or a predetermined level range therein even during the period while the pump unit 3.1-3.6 sucks coating powder from the corresponding powder chamber and pneumatically conveys it to powder spray devices or an individual powder spray device (or in other containers).

[0070] During such a powder spray coating operation, compressed cleaning air is not fed into the corresponding powder chambers or is only fed at reduced pressure.

[0071] Although not explicitly shown in the drawings, it is also conceivable to provide a device for measuring or determining the air pressure prevailing in the respective powder chambers. This is important insofar as it must be ensured that excessive overpressure cannot build up inside the corresponding powder containers 2.1-2.12 due to the introduction of fluidizing compressed air during powder coating operation of the multi-color powder center 1, since the powder containers 2.1-2.12 are generally not designed as high-pressure containers. Therefore, it is preferable if the maximum permissible overpressure in the powder chamber does not exceed 0.5 bar.

[0072] In the last-mentioned embodiment, it is particularly conceivable that the air pressure measured in the corresponding powder chamber of the individual powder containers 2.1-2.12 is fed to a control unit continuously or at predetermined times or events, wherein the amount of fluidizing compressed air fed to the powder chamber per unit of time and / or the amount of fluidizing compressed air discharged from the powder chamber per unit of time via the at least one fluidizing compressed air outlet is / is preferably automatically adjusted depending on the air pressure prevailing in the powder chamber.In the cleaning operation of the multi-color powder center 1, however, it is preferred if, with the aid of the control device, the amount of cleaning compressed air supplied per unit of time to the respective powder chamber and / or the amount of cleaning compressed air discharged per unit of time via the at least one residual powder outlet are / is preferably automatically adjusted as a function of the air pressure prevailing in the powder chamber.

[0073] The multi-color powder center 1 according to the invention, as shown in an exemplary embodiment in the accompanying drawings, has at least one pump unit 3.1-3.6. In the exemplary embodiment shown in the drawings, the pump unit 3.1-3.6 comprises a plurality of dense phase powder pumps, which are preferably individually controllable via the aforementioned control unit and each have a powder inlet for sucking coating powder from one of the powder containers 2.1-2.12 as needed, as well as a powder outlet. The respective powder outlets of the powder pumps 4 of the pump unit 3.1-3.6 are fluidly connected or connectable to a powder spray device.

[0074] As schematically shown, the pump unit 3.1-3.6 is assigned a carriage or slide assembly 6, by means of which the pump unit 3.1-3.6 can be moved in a horizontal plane and above the respective powder containers 2.1-2.12, guided relative to them. For this purpose, the carriage or slide assembly 6 assigned to the pump unit 3.1-3.6 has a corresponding linear drive, which can be controlled via the aforementioned control unit and positioned with respect to the respective powder containers 2.1-2.12 of the multi-color powder center 1.

[0075] The pump unit 3.1-3.6 is further assigned a vertical guide unit in order to be able to move the pump unit 3.1-3.6 or parts thereof in the vertical direction relative to the powder containers 2.1-2.12 of the multi-color powder center 1, if required.

[0076] According to the embodiment of the multi-color powder center 1 according to the invention schematically illustrated in the drawings, the pump unit 3.1-3.6 has a docking unit 8, via which the powder inlets (suction sides) of the powder pumps 4 belonging to the pump unit 3.1-3.6 can be fluidly connected to the interior of one of the powder containers 2.1-2.12, as needed. For this purpose, the docking unit 8 is assigned a vertical guide unit, with which the docking unit 8 can be moved vertically relative to the respective powder pumps 4 of the pump unit 3.1-3.6 and the powder containers 2.1-2.12, as needed.

[0077] The docking unit 8 is movable in the vertical direction relative to the pump unit 3.1-3.6 and relative to the powder container 2.1-2.12 as required for fluidly connecting or separating the suction side of the at least one powder pump 4 with or from the interior of the powder container 2.1-2.12.

[0078] As the detailed representations in FIGs. 2a bis 4 can be removed, the powder containers 2.1-2.8 each have at least one suction channel, preferably formed in a suction pipe, which has a suction opening opening into the interior of the powder container 2.1-2.8 and an opposite discharge opening which opens into a connection 10, wherein the suction side of the at least one powder pump 4 can be fluidly connected to the connection 10 of the powder container 2.1-2.12 via the docking unit 8. The connection 10 is arranged in an upper region and in particular in a cover region 11 of the powder container 2.1-2.8, in such a way that the connection 10 can be fluidly connected to the suction side of the at least one powder pump 4 of the pump unit 3.1-3.6 via the docking unit 8.

[0079] As shown, the docking unit 8 has a first connection 12 assigned to the suction side of the at least one pump unit 3.1-3.6 and at least one second connection 13 assigned to the powder container 2.1-2.12. The first connection 12 is fluidly connected to the second connection 13 via a line section 14, and the line section 14 is designed to be flexible such that the second connection 13 can be moved relative to the first connection 12 over a predetermined distance. The predetermined distance here corresponds to a vertical distance between the second connection 13 of the docking unit 8 and a connection 10 of the powder container 2.1-2.12.

[0080] The second connection 13 of the docking unit 8 is designed to be complementary to a connection 10 of the powder container 2.1-2.12 in such a way that it can be connected to the connection 10 of the powder container 2.1-2.12 in such a way that the at least one powder pump 4 of the pump unit 3.1-3.6 can be fluidly connected to a corresponding intake opening of an intake channel assigned to the powder container 2.1-2.12.

[0081] In particular, the second connection 13 of the docking unit 8 and / or the connection 10 of the powder container 2.1-2.12 are / is designed as a preferably self-closing hose coupling, in particular a self-centering and sealing coupling.

[0082] Although not shown in detail in the drawings, it is advantageous if a cleaning station 5 is also provided in order to be able to clean the pump unit 3.1-3.6 or the components belonging to the pump unit 3.1-3.6 as required, in particular when changing from a first powder type to a different second powder type.

[0083] For this purpose, it is advisable if the pump unit 3.1-3.6 is movable relative to the cleaning station 5 in such a way that it can be cleaned in the cleaning station 5 as needed and, in particular, rinsed with compressed cleaning air.

[0084] Within the scope of this cleaning, it is further conceivable that, with the aid of the cleaning station 5, not only the pump unit 3.1-3.6 and the components belonging to the pump unit 3.1-3.6, in particular the powder pumps 4, but also the line systems leading from the pump unit 3.1-3.6 or the powder pumps 4 to the powder spraying devices can be cleaned. Furthermore, it is advantageous if the cleaning station 5 can also be used to at least partially clean the powder spraying devices assigned to the multi-color powder center 1.

[0085] In particular, it is advantageous if the docking unit 8 assigned to the pump unit 3.1-3.6 is designed to fluidly connect the suction side of the at least one powder pump 4 to a cleaning connection of the cleaning station 5, if required.

[0086] In FIG. 6 A further exemplary embodiment of the multi-color powder center 1 according to the invention is shown schematically and in an isometric view, although for the sake of clarity the powder containers and the cleaning station are not shown.

[0087] In FIG. 7 is a schematic and isometric view of a detailed view of an exemplary embodiment according to FIG. 6 The pump unit 3.1 used is shown.

[0088] In brief, the solution according to the invention is characterized in particular by the fact that a color change can be carried out very flexibly, particularly during an ongoing coating operation, i.e., as quickly as possible, while simultaneously ensuring the quality of the powder supply. In particular, a color change can be carried out within a maximum period of 45 seconds, whereby the multi-color powder center 1 can provide a plurality of different colors or powder types, for example, a total of eight or more powder colors or powder types, simultaneously.

[0089] The powder pumps 4 of the pump units 3.1-3.6 ensure that a plurality of spray coating devices, such as powder spray guns, can be supplied simultaneously from the multi-color powder center 1. According to preferred implementations of the multi-color powder center according to the invention, up to 24 spray guns are connected to the corresponding powder pumps of the multi-color center.

[0090] The individual powder containers are preferably equipped with a fluidization system, whereby the individual powder containers are vented via a preferably centralized venting system.

[0091] The invention is not limited to the exemplary embodiments shown in the drawings, but results from a combination of all features disclosed herein.

[0092] Thus, according to implementations of the multi-color powder center 1 according to the invention, a recovery powder return system is assigned to the multi-color powder center 1 for returning recovery powder to at least one of the powder containers 2.1-2.12 as needed. The recovery powder return system can have at least one return line, in particular in the form of a return hose, which is or can be connected, in particular as needed, to a powder coating booth or a powder coating workstation on the one hand and to one of the powder containers 2.1-2.12 for returning recovery powder to the corresponding powder container 2.1-2.12.

[0093] The at least one return line of the recovery powder return system can be arranged on a carriage or slide arrangement so as to be movable relative to the powder containers 2.1-2.12, in particular so as to be horizontally movable.

[0094] Alternatively or additionally, the at least one return line can be movable relative to the powder containers 2.1-2.12, in particular vertically movable, to form a flow connection with the corresponding powder container 2.1-2.12.

[0095] It is also conceivable for the multi-color powder center 1 to be assigned a powder container venting system for venting the powder containers 2.1-2.12 as needed. The powder container venting system can have at least one venting line, in particular in the form of a venting hose, which is fluidly connected to the powder containers 2.1-2.12, in particular as needed or permanently, for venting the powder containers 2.1-2.12. In this case, the at least one venting line can be movable, in particular horizontally movable, relative to the powder containers 2.1-2.12 on a carriage or slide arrangement.

Claims

1. A multicolor powder center (1) for supplying at least one powder spraying device with different types of coating powder as required, the multicolor powder center (1) comprising: - a first powder container (2.1) for accommodating a first type of coating powder; - at least one second powder container (2.2-2.12) for accommodating a second type of coating powder; and - at least one pump unit (3.1-3.6) having at least one powder pump (4), particularly a dense phase or dilute phase powder pump, the pressure side of which is fluidly connected or connectable to the powder inlet of a powder spraying device, wherein the at least one pump unit (3.1-3.6) and / or the powder containers (2.2-2.12) is / are movable relative to each other such that the suction side of the at least one powder pump (4) is fluidly connected or connectable to either the interior of the first powder container (2.1) or to the interior of the at least one second powder container (2.2-2.12) as required, characterized in that a recovery powder recirculation system is assigned to the multicolor powder center (1) for returning recovery powder into the first powder container (2.1) and / or into the at least one second powder container (2.2-2.12) as needed, wherein the recovery powder recirculation system comprises at least one return line, particularly in the form of a return hose, which is on the one hand fluidly connected or connectable, in particular as needed, to a powder coating booth and the first powder container (2.1) and / or into the at least one second powder container (2.2-2.12) for returning recovery powder into the respective powder container (2.1; 2.2-2.12), wherein the at least one return line is movable, particularly horizontally movable, on a carriage or slide assembly relative to the first powder container (2.1) and / or the at least one second powder container (2.2-2.12), wherein the at least one return line is movable preferably relative to the first powder container (2.1) and / or the at least one second powder container (2.2-2.12), particularly vertically movable, for forming a fluidic connection with the respective powder container (2.1; 2.2-2.12).

2. The multicolor powder center (1) according to claim 1, wherein a cleaning station (5) is further provided for cleaning the pump unit (3.1-3.6) and / or a line system leading from the pump unit (3.1-3.6) to at least one powder spraying device and / or at least one powder spraying device when needed, particularly when changing from a first type of coating powder to a different second type of coating powder.

3. The multicolor powder center (1) according to claim 2, wherein the pump unit (3.1-3.6) is movable relative to the cleaning station (5) such that it can be cleaned and in particular flushed with cleaning compressed air in or at the cleaning station (5) when needed; or wherein the cleaning station (5) is movable relative to the pump unit (3.1-3.6) such that the pump unit (3.1-3.6) can be cleaned and in particular flushed with cleaning compressed air in or at the cleaning station (5) when needed.

4. The multicolor powder center (1) according to claim 2 or 3, wherein the powder containers (2.2-2.12) and the cleaning station (5) are in a straight-line and side-by-side arrangement; and / or wherein a drive is assigned to the pump unit (3.1-3.6) and / or the cleaning station (5) for moving the pump unit (3.1-3.6) relative to the cleaning station (5) such that the pump unit (3.1-3.6) can be cleaned and in particular flushed with cleaning compressed air in or at the cleaning station (5) when needed.

5. The multicolor powder center (1) according to one of claims 1 to 4, wherein a vertical guide unit (7) is assigned to the pump unit (3.1-3.6) for the vertical moving of the pump unit (3.1-3.6) or parts thereof as needed; and / or wherein the pump unit (3.1-3.6) comprises a docking unit (8) via which the suction side of the at least one powder pump (4) can be fluidly connected to the interior of one of the powder containers (2.2-2.12) as required, wherein a vertical guide unit (7) is preferably assigned to the docking unit (8), by means of which the docking unit (8) is vertically movable as needed relative to the at least one powder pump (4) of the pump unit (3.1-3.6) and the powder containers (2.2-2.12).

6. The multicolor powder center (1) according to one of claims 1 to 5, wherein a drive, in particular a linear drive, is assigned to the first powder container (2.1) and / or the at least one second powder container (2.2-2.12) for moving the respective powder container (2.2-2.12) relative to the pump unit (3.1-3.6) as needed, wherein the first powder container (2.1) and / or the at least one second powder container (2.2-2.12) are each preferably able to move relative to the pump unit (3.1-3.6) independently of each other.

7. The multicolor powder center (1) according to one of claims 1 to 6, wherein the pump unit (3.1-3.6) has at least one, in particular independently operable, powder pump (4) arranged in the pump unit (3.1-3.6) such that in a state of the pump unit (3.1-3.6) being coupled to a powder container (2.2-2.12) or a cleaning station (5), the suction side of the at least one powder pump (4) is connected to the interior of the powder container (2.2-2.12) or a cleaning station (5).

8. The multicolor powder center (1) according to one of claims 1 to 7, wherein a first and at least one further second pump unit (3.1-3.6) are in each case provided with at least one powder pump (4), particularly a dense phase powder pump, wherein the pump units (3.1-3.6) are movable relative to the powder containers (2.2-2.12) independently of each other such that - the suction side of the at least one powder pump (4) of the first pump unit (3.1-3.6) and the suction side of the at least one powder pump (4) of the at least one second pump unit (3.1-3.6) are fluidly connected or connectable to either the interior of the first powder container (2.1) or to the interior of the at least one second powder container (2.2-2.12) as required; and / or - the suction side of the at least one powder pump (4) of the first pump unit (3.1-3.6) is fluidly connected or connectable to the interior of a first of the at least two powder containers (2.2-2.12) and the suction side of the at least one powder pump (4) of the second pump unit (3.1-3.6) is fluidly connected or connectable to the interior of the other of the at least two powder containers (2.2-2.12) as required.

9. The multicolor powder center (1) according to claim 8, wherein the first and the at least one further second pump unit (3.1-3.6) are movable relative to each other and relative to the powder containers (2.2-2.12) in at least one horizontal direction; and / or wherein the first and the at least one second powder container (2.2-2.12) are movable relative to each other and relative to the first and the at least one second pump unit (3.1-3.6) in at least one horizontal direction.

10. The multicolor powder center (1) according to one of claims 1 to 9, wherein a plurality of powder containers (2.2-2.12) arranged together in a matrix is provided, and wherein the at least one pump unit (3.1-3.6) is movable in a first horizontal direction and in a second horizontal direction orthogonal to the first horizontal direction relative to the powder containers (2.2-2.12) such that the suction side of the at least one powder pump (4) is fluidly connected or connectable to the interior of one powder container of the plurality of powder containers (2.2-2.12) as required; and / or wherein a plurality of powder containers (2.2-2.12) arranged together in a matrix is provided, and wherein the powder containers (2.2-2.12) are movable in a first horizontal direction and in a second horizontal direction orthogonal to the first horizontal direction relative to the at least one pump unit (3.1-3.6) such that the suction side of the at least one powder pump (4) is fluidly connected or connectable to the interior of one powder container of the plurality of powder containers (2.2-2.12) as required; and / or wherein a plurality of powder containers (2.2-2.12) arranged together in a matrix is provided, and wherein the powder containers (2.2-2.12) are movable in a first horizontal direction and the at least one pump unit (3.1-3.6) is movable in a second horizontal direction orthogonal to the first horizontal direction such that the suction side of the at least one powder pump (4) is fluidly connected or connectable to the interior of one powder container of the plurality of powder containers (2.2-2.12) as required.

11. The multicolor powder center (1) according to one of claims 1 to 10, wherein a powder container venting system is assigned to the multicolor powder center (1) for venting the first powder container (2.1) and / or the at least one second powder container (2.2-2.12) as needed.

12. The multicolor powder center (1) according to claim 11, wherein the powder container venting system comprises at least one vent line, particularly in the form of a venting hose, which is fluidly connected, particularly when required or permanently, to the first powder container (2.1) and / or the at least one second powder container (2.2-2.12) for venting the respective powder container (2.1; 2.2-2.12).

13. The multicolor powder center (1) according to claim 11 or 12, wherein the at least one vent line is movable, particularly horizontally movable, on a carriage or slide assembly relative to the first powder container (2.1) and / or the at least one second powder container (2.2-2.12).