DEVICE AND METHOD FOR SEPARATION OF GLUE PARTICLES FROM AN AEROSOL

Description

[0001] The invention relates to a device and a method for separating glue particles from a glue aerosol, as well as correspondingly designed labeling units, labeling machines and labeling methods.

[0002] It is generally known that labels for containers can be glued not only by means of gluing devices based on glue rollers, but also contactlessly by means of glue jets, which are emitted, for example, from a multitude of nozzles of a glue jet printer, similar to the function of an inkjet printer.

[0003] However, this has the disadvantage that not all of the ejected glue particles can be placed on the respective label. A small proportion of the glue particles are carried away by air currents, creating a glue aerosol that lingers in the vicinity of the glue-jet printer. Over time, this leads to considerable contamination of surrounding machine parts in production and necessitates correspondingly costly cleaning.

[0004] For the separation of glue particles from aerosols collected in the area of ​​hot melt rollers, for example, a device based on a cyclone separator with a funnel-shaped tapered separation area for guiding a cyclone flow and a collection container arranged below the cyclone separator for collecting glue particles running down from the cyclone separator is known from DE 10 2019 203581 A1.

[0005] In such cyclone separators, particles are separated by the cyclone flow of the raw gas at the essentially funnel-shaped side wall and can then migrate from there, driven by gravity and / or the cyclone flow, to the so-called expansion chamber. In this chamber, the cyclone flow calms down, allowing the clean gas produced by the separation process to flow out in the opposite direction at the center of the cyclone flow. The separated particles can be collected in a collection container connected to the expansion chamber.

[0006] To maintain a functioning cyclone flow, the cyclone separator must be airtightly sealed against the environment in the area of ​​the expansion chamber and / or the connected collection container. Furthermore, the collected particles must be removed regularly.

[0007] For this purpose, collected particles can, in principle, be discharged from the cyclone separator via a rotary valve. While this allows emptying during the cyclone separator's operation, it is technically comparatively complex. Furthermore, due to the inherent stickiness of separated adhesive particles, this necessitates difficult and / or frequent cleaning of such valves. If, on the other hand, collection containers are connected and replaced without such valves, the cyclone flow cannot be maintained. During this time, an operational interruption is therefore required.

[0008] US Patent 2006 / 086253 A1 discloses a cyclone separator, for example for flue gas, in which a cooling liquid, which also binds separated particles, flows along the inner wall into a collection container located below. Depending on the embodiment, the cooling liquid can be recirculated to the gas inlet of the separator via a filter and a pump. The lower end of the cyclone separator is designed as a drain line and extends downwards into the upper part of the collection container. Depending on the fill level, the collected cooling liquid can reach the drain line and thus hydrostatically seal it. The cyclone separator includes a restrictor located in the drain line, which creates a back pressure for the discharge of the cleaned gas and simultaneously allows the cooling liquid to drain through the restrictor. There is no extraction system for the cleaned gas; consequently, a back pressure or pressure is present during operation.There is positive pressure above the throttle, and essentially ambient pressure below.

[0009] US Pat. No. 5,053,082 A discloses a cyclone separator located at the top of a solvent-filled extraction column. During operation, the outlet pipe of the cyclone separator is immersed in the solvent to create a seal and create the necessary backflow and overpressure for the removal of the purified gas.

[0010] The invention is based on the object of providing a device and a method for separating glue particles from a glue aerosol, which enable the discharge of separated and collected glue particles with the least possible technical effort while maintaining continuous cyclone operation, i.e. maintaining a functional cyclone flow.

[0011] The problem is solved with a device according to claim 1, labelling units and labelling machines equipped therewith, and with a method according to claim 8.

[0012] The device is therefore used to separate glue particles from a glue aerosol and for this purpose comprises a cyclone separator with a funnel-shaped separation area, in particular tapering downwards, for guiding a cyclone flow and a collecting container arranged below the cyclone separator for collecting glue particles flowing down from the expansion chamber.

[0013] Furthermore, the device includes at least one drain line connected to the separation area, in particular by means of a pressure relief chamber, in a gas-tight manner, which extends downwards into the collection container in order to hydrostatically seal the cyclone separator on the drain side by means of a solvent held in the collection container.

[0014] At least one drainage line consists, for example, of at least one pipe and / or hose.

[0015] The glue particles are essentially free-flowing and / or free-flowing, thus enabling gravity-driven collection after cyclone separation.

[0016] The solvent serves to absorb and remove the adhesive particles. The solvent is, for example, an aqueous cleaning solution, in the simplest case water. Aqueous solutions are particularly suitable due to their relatively low volatility and ease of disposal. However, other solvents are also conceivable in principle, such as alcohols or other organic solvents.

[0017] Preferably, the drain line extends into the collection container to below a predetermined minimum solvent level during ongoing separation / cyclone flow. The outlet of the drain line remains consistently below this minimum level during operation. This creates a hydrostatic seal on the drain side. This prevents the undesirable intake of ambient air through the drain line and ensures reliable separation of the adhesive by the cyclone flow of the adhesive aerosol.

[0018] Preferably, the device further comprises a suction system connected to the clean gas outlet of the cyclone separator, the suction capacity of which is limited and / or regulated in such a way that a negative pressure generated in the drain line draws the solvent through the drain line only to such an extent that a predetermined minimum fill level of the solvent in the collection container outside the drain line is not undercut.

[0019] The negative pressure in the pressure relief chamber and the drain line raises the internal solvent level in the drain line above its external level in the surrounding collection container. This level difference can thus be adjusted appropriately while maintaining the minimum fill level.

[0020] According to the invention, the collection container comprises a level monitor located outside the drain line for measuring the solvent level. The solvent level in the collection container surrounding the drain line can thus be continuously measured. If the level falls below a corresponding threshold, in particular the minimum level, a warning signal could be issued, prompting manual refilling of solvent or automatically triggering a corresponding mechanical refill.

[0021] Preferably, the collection container includes at least one overflow channel for the solvent to define a maximum solvent level and to drain excess solvent from the device. When fresh solvent is added, the fill level initially rises, if necessary, to the lower edge of the overflow channel. This allows the solvent, laden with adhesive particles, to be adequately diluted and, with further refilling, to flow out through the overflow channel and thus be replaced.

[0022] Preferably, the collection container is designed as a depression in a solvent tray, which is configured as a drain with a suitable slope towards the depression / collection container, similar to a funnel. The solvent can then be poured manually from a storage container into the solvent tray, for example. There, it collects (provided the solvent tray is properly aligned) by flowing down into the recessed collection container.

[0023] Preferably, the cyclone separator is arranged in an upright position, and the discharge line is positioned centrally below it and, in particular, coaxially with the separation area. This promotes a cyclone flow suitable for separation, subsequent flow stabilization in the expansion chamber, and gravity-driven drainage of the adhesive particles.

[0024] Preferably, the device further comprises an extraction unit with an extraction line connected to the raw gas inlet of the device and, in particular, with an aerosol shield arranged on the inlet side of the extraction line, especially in the form of an extraction hood, to delimit an extraction area for the glue aerosol.

[0025] Preferably, the device according to at least one of the embodiments described above and / or below is a component of a labeling unit for labeling containers, in particular bottles. The labeling unit then further comprises an associated gluing unit, in particular in the form of a glue jet printer for dispensing glue onto labels for the containers, and a suction unit, in particular as described above, for extracting the aerosol from a working area of ​​the gluing unit. Glue aerosols generated during the gluing process and dispersed in the working area can thus be selectively extracted with relatively low suction power, and the glue particles contained therein can be separated as described.

[0026] Preferably, the labeling unit is then part of a labeling machine, which further includes a container carousel for the continuous transport of the containers during the transfer of the labels to the containers.

[0027] The described process is used to separate glue particles from a glue aerosol. For this purpose, the aerosol is passed through a funnel-shaped separation section of a cyclone separator, which tapers downwards. The glue particles separated there by cyclone flow run / trickle down into a collection container located below.

[0028] Furthermore, a solvent for the glue particles is stored in the collection container. The glue particles run / trickle down into the solvent via a drain line that is gas-tightly connected to the separation area, particularly by means of a pressure-reducing chamber. The drain line is immersed in the solvent, creating a hydrostatic seal. This reliably prevents the intake of outside air through the drain line, thus maintaining a cyclone flow that separates the glue particles.

[0029] Preferably, fresh solvent is refilled mechanically and / or manually via a solvent tray sloping down towards the collection container to maintain a minimum fill level and / or to replace loaded / used solvent in the collection container.

[0030] The solvent level in the collection container outside the drain line is monitored automatically. When the level approaches or reaches the minimum, a warning signal is preferably issued or a mechanical refill of the solvent is triggered.

[0031] Preferably, the solvent is discharged through at least one overflow channel to maintain a maximum fill level in the collection container and to remove the adhesive particles. This enables a technically simple and reliable limitation of the fill level.

[0032] In this process, the extraction rate for the pure gas resulting from the separation of the glue particles is also limited and / or regulated, whereby: a negative pressure generated in the drain line draws in the solvent only to such an extent that a predetermined minimum fill level of the solvent in the collection container outside the drain line is not undercut; or the minimum fill level is adjusted accordingly to the extraction rate.

[0033] Preferably, the solvent stored in the collection container is at least partially replaced with fresh solvent while maintaining the cyclone flow in the cyclone separator. This allows the separation of the glue particles to be carried out continuously, i.e., without interruption for the discharge / disposal of the separated glue particles.

[0034] Preferably, the described method is part of a method for labeling containers, wherein labels are glued in particular by means of glue jet printing and glue aerosols released into the environment are sucked off and glue particles are deposited therefrom using the method according to at least one of the embodiments described above or below.

[0035] The glue aerosol contains, for example, cold glue particles for labeling containers. However, in principle, any type of glue and / or glue mixture suitable for cyclone separation is conceivable.

[0036] A preferred embodiment of the invention is illustrated in the drawings. Figure 1 shows a longitudinal section through the device; Figure 2 shows a detailed view of the collecting container; and Figure 3 shows a schematic plan view of a labeling machine with the device.

[0037] As the Figure 1As can be seen, the device 1 for separating glue particles 2 from a glue aerosol 3 comprises a cyclone separator 4 with a raw gas inlet 4a, a funnel-shaped tapered separation area 4b, an adjoining expansion chamber 4c and a clean gas outlet 4d.

[0038] The basic structure and function of these components of the cyclone separator 4 are generally known and therefore not described in detail. The dimensions and shapes shown are merely examples and can be adapted to suit the properties of the glue aerosol 3 and its glue particles 2.

[0039] The device 1 further comprises a collection container 5 arranged below the cyclone separator 4 for collecting the glue particles 2 separated in the cyclone separator 4 and running off from the separation area 4b and / or the area of ​​the relaxation chamber 4c.

[0040] The device 1 further comprises a separating area 4b which is connected downwards (in the Figure 1 (indicated by dashed lines) or the drain line 6 adjoining the relaxation chamber 4c, which extends downwards into the collection container 5 and hydrostatically seals the cyclone separator 4 on the drain side by means of a solvent 7 held in the collection container 5.

[0041] For this purpose, the drain line 6 is immersed in the solvent 7 at least to a level below a minimum fill level 8. The minimum fill level 8 relates to an area of ​​the collection container 5 immediately surrounding the drain line 6.

[0042] By maintaining the minimum fill level 8 of the solvent 7 in the collecting container 5, unwanted suction of external air on the drain side through the drain line 6 is prevented.

[0043] In the Figure 1Furthermore, an inner fill level 9 of the solvent 7 in the drain line 6 and an outer fill level 10 of the solvent 7 outside the drain line 6 during operation are indicated by way of example. Accordingly, the inner fill level 9 is higher than the outer fill level 10, above which the ambient pressure essentially prevails, due to a negative pressure 11 prevailing in the area of ​​the expansion chamber 4c and the drain line 6 during operation of the cyclone separator 4.

[0044] In the Figure 1 Furthermore, a cyclone flow 12, known in principle, is schematically indicated, with which the glue aerosol 3 flows helically towards the expansion chamber 4c in the form of a raw gas. Also schematically indicated is the flow of a pure gas 13 resulting from the glue aerosol 3 after the glue particles 2 have been separated.

[0045] The cyclone flow 12 is generated in a generally known manner by extracting the clean gas 13. The described hydrostatic seal of the discharge line 6 serves to maintain the functionality of the cyclone flow 12 and to calm it appropriately in the expansion chamber 4c.

[0046] As the Figure 1 As indicated, the discharge line 6 is preferably designed as a pipe coaxially connected to the expansion chamber 4c. However, several discharge lines 6 extending from the expansion chamber 4c are also conceivable, as is the design of at least one discharge line 6 in the form of a hose or the like. The decisive factor is that the respective discharge line 6 is immersed in the solvent 7 present there to below the minimum fill level 8 in order to maintain the cyclone flow 12.

[0047] The drain line 6 is preferably an integral part of the cyclone separator 4, for example, formed as a single piece with it or otherwise permanently connected to it. However, it would also be conceivable to flange the drain line 6 to the cyclone separator 4 in a liquid-tight and gas-tight manner, to insert it into a corresponding fitting on the separator, or the like.

[0048] In the Figure 1 It can also be seen that the collecting container 5 is preferably integrated into a solvent tray 14, which slopes downwards towards the collecting container 5 at a suitable gradient 15 in the sense of a drain for solvent 7 filled into the solvent tray 14. Fresh solvent 7 can then, for example, be manually refilled from a storage container 16 into the solvent tray 14 during ongoing operation of the device 1.

[0049] Likewise, mechanical refilling into the collection container via a supply line and dosing device (not shown) for fresh solvent 7 would be conceivable.

[0050] The collection container 5 is preferably designed as a recess 14a of the solvent tray 14 and then preferably forms the deepest area of ​​the solvent tray 14 with respect to the minimum fill level 8 for the corresponding collection of the solvent 7.

[0051] As the Figure 2As can be seen in a partial view of the device 1, the collection container 5 preferably includes an overflow channel 17 for excess solvent 7'. When fresh solvent 7 is added, it at least partially replaces the solvent 7 already present in the collection container 5, which is loaded with adhesive particles 2, as soon as a maximum fill level 18 of the solvent 7 in the collection container 5, predetermined by the lower edge of the overflow channel 17, is reached. If more fresh solvent 7 is added, solvent 7 loaded with adhesive particles 2 flows out of the device 1 in the form of the schematically indicated excess solvent 7'.

[0052] This renewal process for the solvent 7 held in the device can be carried out without interrupting the cyclone flow 12, i.e. during the ongoing operation of the device 1, which also ensures sufficient cleaning / rinsing of the drain line 6 and the collection container 5 and avoids interruptions in operation for the purpose of removing glue particles 2 from the device 1.

[0053] The collection container 5 could also have other structures for this purpose, for example, a substantially flexible wall structure in the form of a bag or the like. Likewise, the collection container 5 could be designed as a replaceable component of the solvent tray 14 during maintenance.

[0054] It is also conceivable to design the collection container 5 not as a component of, or in combination with, the solvent tray 14. For example, the collection container 5 could be supplied directly with fresh solvent 7 via a supply line, either manually or mechanically, at suitable intervals. In principle, any dosing device for refilling with fresh solvent 7 would be conceivable for this purpose.

[0055] It would also be conceivable to determine the external fill level 10 by means of a [measurement / method] in the Figure 2The level of the solvent 10 is monitored by the level sensor 19, which is shown only schematically and as an example. The level sensor 19 would then allow continuous monitoring during operation to determine whether the external level 10 is adequately above the minimum level 8. If this is not the case, for example, if the external level 10 falls below a suitable threshold, a warning message can be issued to manually refill with fresh solvent 7, or refilling can be triggered automatically, for example, via an associated dosing device for the solvent 7.

[0056] As the Figure 3 As can be seen, the device 1 can include an electronic control unit 20 for controlling and / or regulating the performance of the cyclone separator 4.

[0057] The Figure 3Figure 21 schematically shows a top view of a labeling unit 21 for labeling containers 22 with labels 23. These labels are stored, for example, in a label container 24 in stacks and picked up individually by means of vacuum pallets 25 in a manner known in principle. The vacuum pallets 25 circulate on a pallet carousel 26 in a manner known in principle and transport the labels 23 through the working area 27 of a glue-jet printer 28.

[0058] For the extraction of the glue aerosol 3 from the working area 27 of the glue jet printer 28, the device 1 preferably further comprises an extraction unit 30 with an extraction line 31 and an aerosol shield 32, which may, for example, be designed in the form of an extraction hood.

[0059] A suction unit 33 for drawing in the clean gas 13, for the indirect suction of the glue aerosol 3 and for generating the cyclone flow 12 is also shown schematically.

[0060] It would also be conceivable to design the extraction unit 30 with a separate extraction system (not shown), which would then be arranged upstream of the raw gas inlet 4a of the cyclone separator 4.

[0061] The control unit 20 regulates the suction power of the extraction system 33, preferably such that a suitable negative pressure 11 is generated in the area of ​​the expansion chamber 4c and / or the drain line 6. This allows a suitable level difference between the inner fill level 9 and the outer fill level 10 to be set in order to keep the outer fill level 10 always above the minimum fill level 8. This prevents the fill level from falling below the minimum fill level 8.

[0062] Furthermore, the one in the Figure 2The level monitor 19 shown is connected to the control device 20 to prevent the level from falling below the minimum level 8, for example by issuing suitable warning messages, triggering an automatic refilling process and / or adjusting the suction power.

[0063] In the Figure 3 It can also be seen schematically that the labeling unit 26 with the described device 1 is preferably a component of a labeling machine 41 of a rotating design, in which the containers 22 to be labeled continuously rotate on a container carousel 42 during the transfer of the labels 23 to the containers 22. Such labeling processes are known in principle and therefore will not be explained in detail.

[0064] The described device 1 and the described method enable a substantially continuous labeling of the containers 22 with continuously rotating pallet carousel 26 and container carousel 42 with intermittent cyclone flow 12 in the cyclone separator 4.

[0065] In this way, the separated glue particles 2 can be discharged from the glue aerosol 3 collected in the working area 27 of the glue jet printer 28 without having to interrupt the continuous labeling operation for cleaning or emptying of the collection container 5.

[0066] The hydrostatic seal on the outlet side of the cyclone separator 4 can be implemented with components that are simple in design and easy to clean and / or replace during maintenance work. For example, the solvent tray 14 and the collection container 5 could be cleaned or replaced relatively inexpensively. Similarly, the collection container 5 and / or the corresponding outlet pipe 6 could be replaced separately during maintenance work, i.e., outside of regular production operations. Furthermore, the outlet pipe 6 has no moving parts or surfaces that might be difficult to clean.

[0067] Thus, a cost-effective and, in practice, permanently maintenance-friendly device 1 for continuous operation in the labeling of containers 22 is provided.

Claims

1. A device (1) for separating glue particles (2) from a glue aerosol (3), comprising a cyclone separator (4) having a funnel-shaped tapering separating region (4b) for guiding a cyclone flow (12), a collecting container (5) arranged below the cyclone separator for collecting glue particles running out of the cyclone separator, a discharge line (6) connected in a gas-tight manner to the separating region and projecting downwards into the collecting container (5), to hydrostatically seal the cyclone separator (4) on the outlet side by means of a solvent (7) held in the collecting container (5), in that the outlet line (6) is immersed in the solvent (7) at least to below a minimum filling level (8) of the solvent (7), and a suction device (33) connected to the clean gas outlet (4d) of the cyclone separator (4), the suction power of which is limited and / or regulated in such a way that a vacuum (11) generated in the outlet line (6) draws the solvent (7) through the outlet line (6) only to such an extent that the minimum filling level (8) of the solvent in the collecting container (5) in an area directly surrounding the discharge pipe (6) is not undershot, and wherein the collecting container (5) comprises a level monitor (19) arranged / measuring outside the discharge pipe (6) for measuring the level of the solvent (7).

2. The device according to claim 1, wherein the collecting container (5) has an overflow channel (17) for the solvent (7) in order to predetermine a maximum filling level (18) of the solvent and to conduct glue particles (2) laden / excess solvent (2') out of the device (1).

3. The device according to one of the previous claims, wherein the collecting container (5) is formed as a recess (14a) in a solvent trough (14) which has a slope (15) towards the recess.

4. The device according to one of the previous claims, wherein the cyclone separator (4) is arranged in an upright position and the outlet line (6) is arranged centrally thereunder and in particular coaxially with respect to the separating region (4b).

5. The device according to at least one of the previous claims, further comprising an extraction unit (30) having an extraction line (31) connected to the raw gas inlet (4a) of the cyclone separator (4) and, in particular, having an aerosol shield (32), in particular an extraction hood, arranged on the inlet side with respect to the extraction line (31), for defining an extraction area for the glue aerosol (3).

6. A labeling unit (21) for labeling containers (22), in particular bottles, comprising the device (1) according to at least one of the previous claims, an associated gluing unit (28), in particular in the form of a glue jet printer for ejecting glue onto labels (23) for the containers, and an extraction unit (30) for extracting the aerosol (3) from a working area (27) of the gluing unit.

7. A labeling machine (41) with the labeling unit (21) according to claim 6 and with a container carousel (42) for, in particular, continuously transporting the containers (22) during the transfer of the labels (23) to the containers.

8. A method for separating glue particles (2) from a glue aerosol (3) comprising the device (1) according to at least one of claims 1-5, wherein the latter is passed through a downwardly funnel-shaped tapering separating region (4b) of a cyclone separator (4) and separated glue particles there run down into a collecting container (5) arranged thereunder by means of a cyclone flow (12), wherein a solvent (7) for the glue particles is provided in the collecting container and the glue particles run down into the solvent (7) in a discharge line (6) connected in a gas-tight manner to the separating region (4b), the outlet line being immersed in the solvent (7) in a hydrostatically sealing manner at least to below a minimum filling level (8) with respect to an area of the collecting container (5) directly surrounding the outlet line (6), wherein the filling level (10) of the solvent (7) in the collecting container (5) outside the discharge line (6) is monitored by machine, wherein a suction power for the clean gas (3) resulting after the separation of the glue particles (2) is limited and / or regulated, and wherein: a vacuum (11) resulting therefrom in the discharge line (6) draws in the solvent (7) only to such an extent that the minimum filling level (8) of the solvent in the collecting container (5) outside the discharge line (6) is not fallen below.

9. The method according to claim 8, wherein fresh solvent (7) is added to maintain a minimum level (8) in the collecting container (5) either mechanically and / or manually via a solvent trough (14) sloping down to the collecting container.

10. The method according to claim 8 or 9, wherein the solvent (7) is discharged through at least one overflow channel (17) to maintain a maximum filling level (18) in the collecting container (5) and to discharge the glue particles (2).

11. The method according to one of the claims 8 to 10, wherein the solvent (7) held in the collecting container (5) is at least partially replaced while maintaining the cyclone flow (12) in the cyclone separator (4).

12. A method for labeling containers (22), wherein labels (23) are glued, in particular by means of glue jet pressure, and a glue aerosol (3) that is thereby released into the environment in a stray manner is sucked off and glue particles (2) are deposited therefrom by means of the method according to at least one of claims 8 to 11.