Device for applying hot-melt adhesive to articles

Abstract

The invention relates to a device (1) for applying hot-melt adhesive to articles, comprising at least one application head (5) having at least one adhesive nozzle (5.1), which comprises a nozzle opening (5.2), for applying the hot-melt adhesive to the articles in portions, further comprising at least one heating and / or cooling device (20) configured to heat and / or cool an adhesive thread forming between the nozzle opening (5.2) and the respective article during the application of the hot-melt adhesive in portions, in order to sever the adhesive thread.

Description

[0001] Device for applying hot melt adhesive to articles

[0002] The invention relates to a device for applying hot melt adhesive to articles. Furthermore, the present invention also relates to a packaging machine, in particular a container packaging machine, comprising at least one such device for applying hot melt adhesive.

[0003] Devices or systems for applying adhesives, in particular hot melt adhesives, are generally known. Such devices or systems typically have at least one application head, on which at least one nozzle, namely an adhesive nozzle, is provided, through which the adhesive or hot melt adhesive is dispensed.

[0004] Such devices or systems are also used in the beverage industry, for example, and particularly in packaging machines or systems for the production of container units. In this process, the items to be processed into containers, such as the containers themselves, are coated with spot adhesive to bond them together. Packaging machines or systems of this kind, equipped with a device for applying adhesive or hot melt adhesive, are known, for example, from German patent applications DE 10 2012 100810 A1 and EP 3245 141 B1.

[0005] In the beverage industry, for example, various aspects are particularly important when producing containers from beverage containers, such as PET bottles, in order to manufacture containers of the required quality.

[0006] In known systems, the volume of hot melt adhesive delivered to the adhesive nozzles is measured over an extended period. Furthermore, the opening cycles of one or more adhesive nozzles are monitored, allowing for the calculation of an average amount of hot melt adhesive dispensed per opening cycle based on the delivered volume of hot melt adhesive and the number of opening cycles. In practice, this often presents the problem that the sometimes highly viscous hot melt adhesives used tend to string – also known in technical jargon as "angel hair." This is due to the flow properties of these hot melt adhesives. To solve this problem, compressed air attachments with an integrated air channel system have become established on the application heads. These attachments generate a targeted jet of air that cuts through the angel hair.

[0007] With current technology, air blowers are used to blow threads onto the items in the package so that they adhere to the containers and can then exit the packaging machine. However, the higher the viscosity of the hot melt adhesive used, the larger the nozzle diameter must be, and consequently, the more stable the resulting threads become. Therefore, the air blowers used in the current technology are no longer able to sever the threads without excessive contamination of the items in the package in such a way that they can still be removed from the packaging machine.

[0008] The object of the invention is to provide a device for applying hot melt adhesive to articles which, regardless of the viscosity of the hot melt adhesive, allows reliable severance of the adhesive threads of the thread pull without contamination of the articles.

[0009] This problem is solved by a device for applying hot melt adhesive to articles according to the features of the independent claims. Advantageous further developments and embodiments of the invention are specified in the respective dependent claims.

[0010] According to a first aspect, the present invention relates to a device for applying hot melt adhesive to articles, comprising at least one application head with at least one adhesive nozzle having a nozzle opening for applying the hot melt adhesive to the articles in portions. The device may, for this purpose, include a hot melt adhesive line connected to the application head for supplying the hot melt adhesive to the application head.

[0011] The device can include a hot melt adhesive tank for storing the hot melt adhesive. The hot melt adhesive line can essentially be designed as an adhesive line, for example, as a hose or pipe, particularly as a hot melt hose. Advantageously, the hot melt adhesive line can be connected to the hot melt adhesive tank or storage container, which can be heated, for example, by means of a preferably provided heating device. The hot melt adhesive, which is also synonymously referred to as glue, adhesive, or hot melt adhesive, can be heated by the heating device to a predetermined temperature, in particular to a melting temperature and / or processing temperature, so that the hot melt adhesive is maintained in a viscous, flowable form. The hot melt adhesive is also conveyed in this viscous, flowable state in the hot melt adhesive line.

[0012] The at least one application head provided in the device, which in this case can also be referred to as an application head or applicator head, or as an adhesive application head or glue application head, is designed, for example, in a manner known to those skilled in the art. In the present system, several application heads can also be provided, connected in parallel or in series, each of the several application heads preferably being equipped with at least one adhesive nozzle.

[0013] The precise, predetermined quantity of hot melt adhesive is dispensed from the adhesive nozzle(s) at the applicator head(s) and applied to the containers to create pinpoint adhesive bonds. Each of these dispensing and application events can be referred to as an application process or a shot. The applicator head(s) of the device operate, for example, at a frequency of up to 500 application processes per minute. The "device" can also be understood, within the meaning of the present invention, as a system for applying hot melt adhesive and can be used, in particular, in a machine or system for the production of containerized units, such as multipacks, or can be a part of such a machine or system.In particular, the device can be used in the beverage industry and integrated into a treatment and / or packaging machine for treating and / or packaging beverage containers. The articles to which the hot melt adhesive is applied by means of the present device are, for example, containers (especially beverage containers, such as bottles, cans, or beverage cartons) or packaging material that at least partially surrounds the containers (e.g., cardboard blanks for forming a tray or a wrap-around carton). PET bottles are particularly preferred.

[0014] Furthermore, the device according to the invention has at least one heating and / or cooling device designed to heat and / or cool an adhesive thread that forms between the nozzle opening and the respective article during the portion-wise application of the hot melt adhesive, in order to cut the adhesive thread.

[0015] The present invention offers a reliable solution to the frequently occurring problem in the application of high-viscosity hot melt adhesives, namely the uncontrolled formation of threads, also known as "angel hair". By using a heating and / or cooling device, the adhesive thread is selectively thermally treated so that it is cut precisely and reliably. In contrast to conventional compressed air systems, this is achieved regardless of the viscosity of the adhesive and without contaminating the contents of the container with adhesive residue.

[0016] A key advantage of this technology lies in its increased process reliability. Production errors caused by uncontrolled adhesive strands are avoided, thereby increasing the operational efficiency of the packaging machine. Simultaneously, the quality of the produced containers is improved, as cleanly cut adhesive strands ensure an aesthetically flawless bond. The device is also characterized by its flexibility. It can operate with various hot melt adhesives and viscosity grades without requiring any mechanical adjustments. This makes it suitable for a wide range of applications and increases versatility in the production process. A further advantage is the reduction in maintenance and production downtime. Since less adhesive residue adheres uncontrollably to the device or the products, cleaning requirements are significantly reduced. This saves not only time but also costs.In summary, the invention offers a technologically advanced solution that makes the adhesive application process more efficient, cleaner, and more reliable. It helps to reduce operating costs, increase production quality, and maximize flexibility in adhesive processing.

[0017] According to an advantageous embodiment, the applicator head may have at least one nozzle attachment provided on the adhesive nozzle, wherein the heating and / or cooling device is a component of the nozzle attachment and / or integrated into the nozzle attachment. Alternatively, the heating and / or cooling device may be designed as a nozzle attachment itself. Integrating the heating and / or cooling device directly into the nozzle attachment allows for a compact design of the applicator head. Additional external components or complex wiring and cables are eliminated, which reduces the space requirement and simplifies handling.

[0018] The nozzle attachment can be detachably and / or replaceably mounted on the applicator head in the area of ​​the adhesive nozzle. For example, the nozzle attachment can be screwed onto the applicator head or detachably fastened using a clip connection. Because the nozzle attachment is detachably and / or replaceably mounted on the applicator head in the area of ​​the adhesive nozzle, it can be quickly and easily replaced when worn or for cleaning. This reduces maintenance times and minimizes system downtime.

[0019] Furthermore, an integrated air duct system can be advantageously incorporated into the nozzle attachment, enabling it to not only thermally treat the adhesive threads but also sever them with a targeted air jet. This integrated air duct system effectively complements the thermal treatment of the adhesive threads with a focused air jet. This combination ensures that the forming adhesive threads are not only reliably severed by thermal action but also precisely directed away to prevent uncontrolled adhesion to the articles. The targeted combination of thermal and pneumatic treatment significantly reduces the risk of production defects. Adhesive threads are reliably separated and removed, thus increasing process stability and, consequently, production quality.However, this design variant offers an extremely efficient, flexible and maintenance-friendly solution that increases process reliability, reduces operating costs and sustainably improves production quality.

[0020] According to an advantageous embodiment, the nozzle attachment may comprise at least one base body, wherein the base body has a mounting section with a front and a rear opposite the front, as well as a free central area for the unimpeded flow of hot melt adhesive from the nozzle opening of the application head through the base body, and wherein the rear of the mounting section of the base body faces the nozzle opening. The free central area in the base body enables the unimpeded and precise flow of the hot melt adhesive from the nozzle opening to the target area. This ensures that the adhesive flow is not impaired or disrupted and enables uniform adhesive application. The clear separation of the mounting section and the free central area prevents adhesive from adhering to unwanted areas in the nozzle attachment or from forming residues.This minimizes the risk of blockages or uncontrolled adhesive application. The mounting section of the base body ensures stable and precise positioning of the nozzle attachment on the adhesive nozzle. This precise arrangement enables repeatable and consistent adhesive application. According to an advantageous embodiment, the free central area can be provided with a drainage section extending towards the underside of the base body, wherein the drainage section forms an opening on the underside for draining hot melt adhesive emanating from the application head, and wherein the drainage section preferably widens in a V-shape or arc towards the opening. The drainage section enables the controlled downward drainage of excess hot melt adhesive from the adhesive nozzle.This prevents uncontrolled flow or dripping of the hot melt adhesive and ensures precise adhesive application. The V-shaped or arc-shaped widening of the drain section prevents adhesive residue from accumulating on the inner walls or edges of the drain section. This reduces the risk of blockages and facilitates cleaning.

[0021] According to an advantageous embodiment, the heating and / or cooling device can be arranged on the front of the mounting section, particularly adjacent to the free central area, or it can be integrated into the base body. Preferably, the mounting section is plate-shaped. The plate-shaped mounting section ensures a stable and robust attachment of the nozzle attachment to the adhesive nozzle. This prevents vibrations or unwanted movements that could impair the accuracy of the adhesive application. Arranging the heating and / or cooling device on the front of the mounting section or directly in the base body allows for precise thermal treatment of the forming adhesive filament. This ensures that the filament is heated or cooled precisely at the critical point to guarantee reliable severance.The proximity of the heating and / or cooling unit to the open central area ensures direct and efficient heat transfer to the adhesive filament. Energy losses due to long transmission paths are minimized, reducing energy consumption and increasing system efficiency. Integrating the heating and / or cooling unit into the base or positioning it on the front allows for a space-saving design. This reduces the overall size of the application head, facilitating installation in confined production environments. The combination of the targeted positioning of the heating and / or cooling unit and the plate-shaped mounting section enables precise, efficient, and reliable thermal treatment of the adhesive filaments. This results in greater process stability, reduced downtime, increased operational efficiency, and overall improved production quality.

[0022] According to an advantageous embodiment, the base body may further comprise a sleeve section that connects to the front of the mounting section and at least partially encloses the free central area. The sleeve section, in particular, coaxially encloses a central axis that runs substantially perpendicular to the front and preferably through the center of the free central area of ​​the mounting section of the base body. The sleeve section ensures precise and stable guidance of the adhesive thread along the central axis. This prevents uncontrolled spreading or deviation of the adhesive thread during the dispensing process and ensures that the adhesive is applied precisely to the target position. The partially coaxial arrangement of the sleeve section stabilizes the adhesive thread, which is particularly advantageous for high-viscosity hot melt adhesives.This prevents the adhesive filament from vibrating uncontrollably or from unintentionally coming into contact with adjacent surfaces. The sleeve section protects the adhesive filament from external disturbances such as air currents or ambient temperature fluctuations. This increases process reliability and ensures a consistent adhesive application. The coaxial arrangement along the central axis ensures that the adhesive filament always exits the nozzle opening centered and uniformly. This contributes to higher precision in adhesive application. The sleeve section can be designed to be adaptable or interchangeable, depending on application requirements. This allows for flexible adaptation to different adhesive types, viscosities, or process conditions. The sleeve section improves the precise guidance, stabilization, and targeted thermal treatment of the adhesive filament along the central axis.In an advantageous embodiment, the heating and / or cooling unit can be integrated into the sleeve section. Integrating the heating and / or cooling unit directly into the sleeve section enables precise thermal treatment of the adhesive filament immediately at the nozzle opening of the adhesive nozzle. This allows the adhesive filament to be heated or cooled with pinpoint accuracy, ensuring a reliable and clean cut. Because the heating and / or cooling unit is housed directly within the sleeve section, the heat or cooling is transferred to the adhesive filament efficiently and without significant energy loss. This increases the energy efficiency of the system. Integration into the sleeve section allows for a space-saving and compact design. Additional components or external parts for thermal treatment are eliminated, making the assembly simpler and less prone to errors.Furthermore, direct integration into the spool section ensures a uniform temperature distribution across its surface. This prevents temperature variations and improves the consistency of the thermal treatment. Integrating the heating and / or cooling unit into the spool section provides targeted, efficient, and reliable thermal treatment of the adhesive thread. This results in improved process stability, reduced stringing, higher energy efficiency, and overall enhanced product quality.

[0023] In an advantageous embodiment, thermal insulation can be provided between the heating and / or cooling unit and a wall of the sleeve section. This thermal insulation prevents heat or cold from being dissipated uncontrollably to the environment through the sleeve section wall. As a result, the energy remains focused on the treatment of the adhesive thread, significantly improving energy efficiency. The insulation also ensures that the temperature of the heating and / or cooling unit remains stable and constant. External temperature or environmental influences have less of an impact, increasing the precision and reliability of the thermal treatment. Because the heating and / or cooling unit is thermally insulated, its components react more quickly to temperature changes. This allows for more precise control of the heating or cooling processes, which is particularly advantageous in highly dynamic processes.Since thermal insulation minimizes temperature losses, the adhesive filament remains under stable thermal conditions. This results in more reliable severance and cleaner adhesive application. The thermal insulation between the heating and / or cooling unit and the sleeve section wall enables targeted and energy-efficient thermal treatment of the adhesive filament. This leads to consistent temperature control, greater energy savings, improved process stability, and safer, longer-lasting operation of the device. Integrating the insulation thus optimizes the performance, reliability, and cost-effectiveness of the entire adhesive application system.

[0024] According to an advantageous embodiment, the heating and / or cooling device can be arranged at least partially coaxially around the central axis within the sleeve section. This coaxial arrangement ensures a uniform temperature distribution around the adhesive filament. This prevents local overheating or underheating and enables precise thermal treatment of the adhesive filament. The coaxial arrangement ensures that the adhesive filament is guided stably under uniform thermal conditions throughout its entire path through the sleeve section. This prevents the filament from deviating from the center or moving uncontrollably.

[0025] According to an advantageous embodiment, the heating and / or cooling device can be designed and controlled to maintain a constant temperature within a sleeve chamber defined by the wall of the sleeve section. Maintaining a constant temperature within the sleeve chamber ensures precise and stable thermal treatment of the adhesive thread, resulting in reliable severing of the forming adhesive threads. Different adhesives have different temperature requirements. The adjustable constant temperature allows the device to be flexibly adapted to the specific properties and viscosities of various adhesive types. Targeted and constant temperature maintenance ensures efficient energy use. Heat or cooling losses are minimized, reducing energy consumption and operating costs.The ability to maintain a constant temperature within the sleeve space limited by the wall of the sleeve section leads to high process stability, precise temperature control and optimized adhesive application.

[0026] According to an advantageous embodiment, the heating and / or cooling device can be designed as an electric heating device, in particular as a heating coil device, as a device for generating an electric arc or as a heating ceramic, or as an optical heating device, in particular as a laser beam device.

[0027] The heating coil assembly can comprise at least one electrically conductive heating wire that heats up thermally when an electric current is applied. This heating wire can be designed as a heating coil, particularly a spiral heating coil. Its spiral structure ensures a homogeneous temperature distribution within the sleeve. Heating coils are relatively inexpensive and easy to replace.

[0028] The heating ceramic can be made of a ceramic material that directly converts electrical energy into heat. Heating ceramics are wear-resistant and resistant to thermal stress. The device for generating an electric arc can, in particular, comprise two high-voltage electrodes that are supplied with electrical energy from a transformer in such a way that an electric arc forms between the two high-voltage electrodes.

[0029] Advantageously, the laser beam device can be configured as a diode laser or a fiber laser. The diode laser can be configured to generate laser light through semiconductor materials, which is directed directly or via a fiber onto the forming adhesive filament. The fiber laser can generate the laser radiation through an active optical fiber and direct it onto the forming adhesive filament. Preferably, the laser beam is directed directly onto the adhesive filament without redirection. Advantageously, the heating and / or cooling device can be configured for continuous or pulsed heating and / or cooling, and in particular, can be controlled for continuous or pulsed heating and / or cooling.

[0030] Electric heating devices, especially heating coils or ceramic heating elements, enable rapid and precise temperature increases. Optical heating devices, such as laser beam systems, allow for the creation of targeted heating zones that react instantly to temperature changes. Laser beam systems, in particular, enable pinpoint heating of the adhesive filament or specific areas within the sleeve cavity. This minimizes unnecessary energy losses and prevents undesirable thermal effects on adjacent areas. Electric ceramic heating elements and heating coils ensure uniform heat distribution along the walls of the sleeve section. This prevents local hotspots or temperature variations that could impair adhesive quality. The heating and / or cooling device can be configured as an electric heating element (e.g., heating coil, arc, or ceramic heating element) or as an optical heating element (e.g., laser beam).The laser beam system offers high flexibility, precision, and energy efficiency in temperature control. These technical advantages contribute to stable, reliable, and economical adhesive application, reduce downtime and maintenance, and enable optimal adaptation to various production requirements.

[0031] According to an advantageous embodiment, the heating and / or cooling device can be designed as a fluid cooling device, in particular as a gas supply device. A fluid cooling device, especially a gas supply device, offers an effective way to selectively cool the temperature of the adhesive filament. The fluid cooling device can directly influence the temperature in the area of ​​the adhesive filament through the targeted use of gaseous media such as compressed air or inert gases (e.g., nitrogen or CO2). The directed application of a gas to the adhesive filament achieves immediate and localized cooling. This makes it possible to quickly and effectively influence the viscosity of the hot melt adhesive, thereby causing the adhesive filament, which is still flexible, to solidify.The gas supply unit can be designed so that the airflow, in both quantity and direction, can be precisely adjusted to the adhesive thread. This flexibility allows for precise adaptation to different adhesive types and viscosities, as well as to the varying requirements of the packaging machine. The fluid cooling unit, particularly in the form of a gas supply unit, offers a powerful way to precisely control the temperature of the adhesive thread.

[0032] According to an advantageous embodiment, the base body may be provided with a gas channel system with at least one outlet opening, wherein the gas channel system with the outlet opening is configured to supply the adhesive filament with a gas for cooling. Advantageously, the gas channel system may also have several outlet openings, for example, opposite and converging outlet openings. The gas channel system directs the gas, in particular the cooling gas, preferably directly to the adhesive filament exiting the nozzle opening of the adhesive nozzle and supplies it with the gas, in particular the cooling gas. This enables precise cooling of the adhesive filament directly in the area of ​​the nozzle opening, without affecting the entire application area.This targeted guidance improves cooling performance and enables rapid temperature regulation, which is advantageous for operation with different adhesive types and viscosities.

[0033] According to an advantageous embodiment, it can be provided that at least one foaming device is provided for applying a foaming gas, in particular nitrogen, to the hot melt adhesive to produce a foam adhesive, and that the device is designed for applying foam adhesive to articles.

[0034] Preferably, a foam adhesive with a defined foaming rate is applied to the articles. Embodiments are also conceivable in which the hot melt adhesive tank and the foaming device are arranged spatially adjacent to each other in such a way as to form an essentially integrated or combined structural unit. For example, the foaming device connects directly to the hot melt adhesive tank, so that the hot melt adhesive line is limited to a minimal transition between an outlet of the hot melt adhesive tank and an inlet of the foaming device.

[0035] Preferably, the foaming device for producing a foam adhesive is designed with a defined foaming rate, which in this case can also be referred to as the foaming rate or the foaming rate.

[0036] The foaming rate essentially indicates the volume ratio in which gas is introduced into the hot melt adhesive when it is applied. The foaming rate thus provides information about the volume increase of the hot melt adhesive during foaming, i.e., the relative increase in volume experienced by the hot melt adhesive during foaming, particularly due to gas inclusions or the gas introduced into the hot melt adhesive by applying the gas. This increase is determined by the relative amount of gas in the hot melt adhesive-gas mixture and by the corresponding expansion of the introduced gas upon pressure release at the nozzle outlet of the applicator head.

[0037] The foaming action increases the volume of the hot melt adhesive while reducing the actual amount of material used. Because the hot melt adhesive is mixed with gas, less adhesive is needed to cover the same area. This reduction in adhesive consumption lowers production costs and conserves resources. Significant material savings can be achieved, especially in high-volume applications such as the production of multipacks for the beverage industry. A key advantage of using foam adhesive with thin-walled PET bottles is the protection of the delicate material structure, particularly preventing delamination of the laminate layers. PET bottles, especially thin-walled versions, are often composed of multiple layers of material that provide specific properties such as durability and protection.In particular, when opening the packs, i.e. separating the containers, conventional hot melt adhesives can damage the sensitive laminate layers, which can lead to delamination.

[0038] According to a further aspect, the present invention relates to a packaging machine, in particular a container packaging machine, comprising at least one device for applying hot melt adhesive according to the above description.

[0039] According to an advantageous embodiment, it can be provided that the at least one device for applying hot melt adhesive is designed to apply the hot melt adhesive to containers in order to produce containers from containers connected to each other by means of adhesive points.

[0040] According to an advantageous embodiment, the packaging machine may include a gluing station, which has at least one device for applying hot melt adhesive, and a setting station downstream of the gluing station for joining the containers provided with adhesive dots to form bundles. The packaging machine preferably has an orientation device arranged upstream of the gluing station for aligning the containers according to a predetermined target orientation and / or an application device arranged downstream of the setting station for applying a carrying handle to the bundles. In particular, the packaging machine is designed for forming packaging units from articles, especially containers.

[0041] The packaging machine can, for example, comprise a treatment station, which is, for instance, a gluing station with at least one device for applying hot melt adhesive as described above, with at least two rotating conveying rotors driven by a rotary drive, wherein the conveying rotors are provided on their circumference with receptacles for the articles, and with a setting and compaction station downstream. For example, the setting and compaction station can have at least two parallel setting guides for the articles, which open between the two conveying rotors, and with a guide device for transferring the articles from the conveying rotors to the setting and compaction station.Preferably, the setting and compaction station can have at least two supports arranged side by side, and each support can include at least one setting guide, wherein each setting guide contains at least one endless guide belt running between at least two deflections, at least one of which is driven.

[0042] The invention will be explained in more detail below with reference to exemplary embodiments shown in the figures. The figures show:

[0043] Fig. 1, in an exemplary and highly simplified manner, sketches an embodiment of a device for applying hot melt adhesive to articles using a rough schematic block diagram and

[0044] Fig. 2 shows a roughly schematic view of an application head with an exemplary embodiment of a nozzle attachment provided thereon with a heating and / or cooling device;

[0045] Figs. 3a to 3c show, in roughly schematic form, different views of an exemplary embodiment of a freestanding nozzle attachment with a heating and / or cooling device;

[0046] Fig. 4 shows a rough schematic view of an applicator head with a further exemplary embodiment of a heating and / or cooling device; and

[0047] Fig. 5 shows, in a rough schematic representation, another exemplary embodiment of a freestanding nozzle attachment with a heating and / or cooling device. For identical or similarly functioning elements of the invention, identical reference numerals are used in the figures where appropriate. Furthermore, for the sake of clarity, only those reference numerals necessary for describing the respective figure are shown in the individual figures. The invention is also presented in the figures only as a schematic view to illustrate its operation. In particular, the illustrations in the figures serve only to explain the fundamental principle of the invention.

[0048] The figures show exemplary embodiments of a device 1 for applying hot melt adhesive to articles, each in a highly simplified and roughly schematic, diagrammatic representation. The device 1 is preferably used in a packaging machine, in particular a container packaging machine, for the production of container packages, for example in the beverage industry, and is not shown in detail in the figures. The device 1 can also be a component of such a packaging machine and, as such, can be structurally integrated into the packaging machine.

[0049] In particular, the packaging machine can comprise a gluing station which has at least one device (1) for applying hot melt adhesive, and a setting station following the gluing station for joining the containers provided with adhesive dots to form bundles, wherein the packaging machine preferably has an orientation device arranged upstream of the gluing station for aligning the containers according to a predetermined target orientation and / or an application device arranged downstream of the setting station for applying a carrying handle to the bundles.

[0050] The device 1 shown in Figure 1 for applying hot melt adhesive to articles comprises at least one application head 5 with at least one adhesive nozzle 5.1 having a nozzle opening 5.2 for applying the hot melt adhesive to the articles in portions. Furthermore, the device 1 comprises at least one heating and / or cooling device 20, which is designed to heat and / or cool an adhesive thread that forms between the nozzle opening 5.2 and the respective article during the portioned application of the hot melt adhesive, in order to cut the adhesive thread.

[0051] The device 1 generally includes an adhesive supply for providing a hot melt adhesive, specifically an adhesive supply with a hot melt adhesive tank 2 for storing the hot melt adhesive. In the illustrated examples, the hot melt adhesive tank 2 is associated with a pre-melter in which the hot melt adhesive can be heated, for example, to a suitable temperature corresponding to a melting or processing temperature, so that the hot melt adhesive is in a viscous, flowable form and is available for use in this state. For this purpose, a heating device (not shown and not further described in the figures) is provided, by which, in particular, the hot melt adhesive tank 2 can be heated.

[0052] Furthermore, the device 1 has at least one applicator head 5 for applying the hot melt adhesive to the articles, in particular the containers, and a hot melt adhesive line 3 fluidically connecting the at least one applicator head 5 with the hot melt adhesive tank 2 for supplying the hot melt adhesive to the at least one applicator head 5.

[0053] However, the device 1 can also have an optional foaming device 7 and is thus designed for applying foam adhesive to articles, since a foam adhesive is produced from the hot melt adhesive by means of the respective foaming device 7 and applied to the articles as foam adhesive.

[0054] Starting from and connected to the hot melt adhesive tank 2, the hot melt adhesive line 3 leads to the foaming device 7 belonging to the device 1, which is also connected to the hot melt adhesive line 3. The hot melt adhesive tank 2 is thus fluidically sealed to the foaming device 7 via the hot melt adhesive line 3, so that the hot melt adhesive, which is present in viscous, flowable form in the hot melt adhesive tank 2, can be supplied to the foaming device 7 via the hot melt adhesive line 3. The hot melt adhesive is supplied to the foaming device 7 at the inlet side via a hot melt adhesive inlet 11 of the foaming device 7.

[0055] The foaming device 7, which can also be referred to as a foaming device, is designed to pressurize the hot melt adhesive supplied by means of a pump unit 14 belonging to the device 1 with a gas, in particular nitrogen, and in this way to produce a hot melt adhesive-gas mixture from the supplied hot melt adhesive in order to create a foam adhesive.

[0056] To supply the hot melt adhesive-gas mixture or the foam adhesive produced in the foaming unit 7 to the at least one application head 5 intended for applying the foam adhesive to the containers, the hot melt adhesive line 3 has a supply line 3a which is connected to the foaming unit 7 at its outlet, namely to an outlet 12 of the foaming unit 7 in a fluidically tight manner. The hot melt adhesive-gas mixture produced in the foaming unit 7 is conveyed out of the foaming unit 7 via the supply line 3a of the hot melt adhesive line 3 and transported towards the application head(s) 5.

[0057] In the example shown in Figure 1, the device 1 has one applicator head 5. However, embodiments of the device 1 with multiple applicator heads 5 are also conceivable. The applicator head 5(s) is / are fluidically connected to the foaming device 7 via the supply line 3a of the hot melt adhesive line 3, with each applicator head 5 being equipped with a respective adhesive nozzle 5.1 with a respective nozzle opening 5.2, through which the foam adhesive is dispensed or applied during operation of the device 1 and applied to the articles. In particular, an adhesive thread can form between the respective nozzle opening 5.2 and the respective article, which is cut by means of the heating and / or cooling device 20. As can be seen particularly in Figures 2 and 3, the applicator head 5 has at least one nozzle attachment 21 provided on the adhesive nozzle 5.1.Advantageously, the heating and / or cooling device 20 is a component of the nozzle attachment 21 and / or integrated into the nozzle attachment 21. In more detail, the nozzle attachment 21 is preferably detachably arranged on the application head 5, such that the nozzle attachment 21 is functionally assigned to, or provided on, the adhesive nozzle 5.1.

[0058] The nozzle attachment 21 comprises at least one base body 22 (see Figures 3a to 3c), wherein the base body 22 has a mounting section 23 with a front face VS and a rear face RS opposite the front face VS, as well as a free central area MB for the unimpeded passage of hot melt adhesive from the nozzle opening 5.2 of the adhesive nozzle 5.1 of the application head 5 through the base body 22. The rear face RS of the mounting section 23 of the base body 22 faces the nozzle opening 5.2.

[0059] As can also be seen particularly in Figures 3a to 3c, the free central area MB has a drainage section 24 extending towards a bottom surface US of the base body 22. The drainage section 24 forms an opening 25 on the bottom surface US of the base body 22, which is designed to drain hot melt adhesive emanating from the application head 5. The drainage section 24 preferably widens in a V-shape or arc shape towards the opening 25.

[0060] It is particularly advantageous for the heating and / or cooling device 20 to be arranged on the front side VS of the mounting section 23, and especially adjacent to the free central area MB. Alternatively, the heating and / or cooling device 20 can also be integrated into the base body 22.

[0061] The base body 22 can also have a sleeve section 28 which connects to the front of the mounting section 23 and at least partially encloses the free central area MB. In particular, the sleeve section 28 encloses a central axis MA, which runs essentially perpendicular to the front face VS and preferably through the center of the free central area MB of the mounting section 23 of the base body 22, at least partially coaxially. As can be seen particularly in Figures 3a to 3c, the heating and / or cooling device 20 is received, in particular arranged or integrated, in the sleeve section 28 of the base body 22. In addition, thermal insulation 32 is provided between the heating and / or cooling device 20 and a wall 30 of the sleeve section 28. The heating and / or cooling device 20 is arranged at least partially coaxially around the central axis MA in the sleeve section 28.

[0062] However, the heating and / or cooling device 20 is advantageously designed and controllable in such a way that a constant temperature can be set in a sleeve space limited by the wall 30 of the sleeve section 28.

[0063] The heating and / or cooling device 20 can be configured as an electric heating device, in particular as a heating coil device 34 (shown in Figures 3a to 3c), as a device for generating an electric arc 36 (shown in Figure 4), or as a heating ceramic 38 (shown in Figure 2). Alternatively, the heating and / or cooling device 20 can also be configured as an optical heating device, in particular as a laser beam device.

[0064] In more detail, the heating coil assembly 34 of Figures 3a to 3c can be integrated into the sleeve section 28 of the nozzle attachment 21 and may comprise at least one electrically conductive heating wire that is thermally heated by a current applied (as schematically indicated). The heating wire can be designed as a heating coil, in particular as a spiral heating coil. Due to its spiral structure, the heating coil ensures a homogeneous temperature distribution in the sleeve chamber of the sleeve section 28.

[0065] The heating and / or cooling device 20, designed as a heating ceramic 38 in the embodiment shown in Figure 2, can be made of a ceramic material that directly converts electrical energy into heat. The device for generating an electric arc 36, shown schematically in Figure 4, can in particular comprise two high-voltage electrodes which are supplied with electrical energy by an indicated transformer such that an electric arc is formed between the two high-voltage electrodes.

[0066] Figure 5 shows an embodiment in which the heating and / or cooling device 20 is designed as a fluid cooling device 40, in particular as a gas supply device. Embodiments are also conceivable in which a heating device and a cooling device 20 are provided. This allows the adhesive thread formed during application to be selectively thermally treated. In particular, the cooling device shown in Figure 5 can be provided in addition to an embodiment of a heating device according to one of Figures 2 to 4 – the embodiments can therefore be combined. For this purpose, a gas channel system 42 with at least one outlet opening 43 can be formed in the base body 21, wherein the gas channel system 42 with the outlet opening 43 is designed to supply the adhesive thread with a gas for cooling.

[0067] The invention has been described above using exemplary embodiments. It is understood that numerous modifications or adaptations are possible without departing from the underlying inventive concept. Reference numerals

[0068] 1 Device for applying hot melt adhesive 2 Hot melt adhesive tank

[0069] 3 Hot melt adhesive line

[0070] 3a Supply lines

[0071] 5 applicator head

[0072] 5.1 Adhesive nozzle

[0073] 5.2 Nozzle opening

[0074] 6 additional pump units

[0075] 7 Foam forming device

[0076] 11 Hot melt adhesive inlet

[0077] 12 Exit

[0078] 13 Gas supply

[0079] 13a Gas storage tank

[0080] 14 Pump unit

[0081] 20 Heating and / or cooling equipment

[0082] 21 nozzle attachment

[0083] 22 Basic shapes

[0084] 23 Fastening section

[0085] 24 Drainage section

[0086] 25 Opening

[0087] 28 Sleeve section

[0088] 30 wall

[0089] 32 Insulation

[0090] 34 Heating coil device

[0091] 36 Device for generating an electric arc 38 Heating ceramic

[0092] 40 Fluid cooling unit

[0093] 42 Gas duct system

[0094] 44 Exit opening MA Center axis MB Center area VS Front RS Rear US Bottom

Claims

25 Patent claims 1. Device (1) for applying hot melt adhesive to articles, comprising at least one application head (5) with at least one adhesive nozzle (5.1) having a nozzle opening (5.2) for applying the hot melt adhesive to the articles in portions, further comprising at least one heating and / or cooling device (20) designed to heat and / or cool an adhesive thread that forms between the nozzle opening (5.2) and the respective article during the portion application of the hot melt adhesive in order to cut the adhesive thread.

2. Device (1) according to claim 1, characterized in that the application head (5) has at least one nozzle attachment (21) provided on the adhesive nozzle (5.1), wherein the heating and / or cooling device (20) is a component of the nozzle attachment (21) and / or is integrated into the nozzle attachment (21).

3. Device (1) according to claim 2, characterized in that the nozzle attachment (21) comprises at least one base body (22), wherein the base body (22) has a mounting section (23) with a front (VS) and a rear (RS) opposite the front (VS) as well as a free central area (MB) for the unimpeded passage of hot melt adhesive from the nozzle opening (5.2) of the application head (5) through the base body (22) and wherein the base body (22) faces the nozzle opening (5.2) with the rear (RS) of the mounting section (23).

4. Device (1) according to claim 3, characterized in that the free central area (MB) has a drainage section (24) extending towards a bottom side (US) of the base body (22), wherein the drainage section (24) forms an opening (25) on the bottom side (US) for draining hot melt adhesive emanating from the application head (5), wherein the drainage section (24) preferably widens in a V-shape or arc shape towards the opening (25).

5. Device (1) according to claim 3 or 4, characterized in that the heating and / or cooling device (20) is arranged on the front side (VS) of the fastening section (23), in particular adjacent to the free central area (MB), or that the heating and / or cooling device (20) is integrated into the base body (22).

6. Device (1) according to one of claims 3 to 5, characterized in that the base body (22) further comprises a sleeve section (28) which connects to the front of the fastening section (23) and at least partially encloses the free central area (MB), wherein the sleeve section (28) in particular coaxially encloses a central axis (MA) which is substantially perpendicular to the front (VS) and preferably extends through a center of the free central area (MB) of the fastening section (23) of the base body (22).

7. Device (1) according to claim 6, characterized in that the heating and / or cooling device (20) is accommodated in the sleeve section (28).

8. Device (1) according to claim 7, characterized in that thermal insulation (32) is provided between the heating and / or cooling device (20) and a wall (30) of the sleeve section (28).

9. Device (1) according to one of claims 7 to 8, characterized in that the heating and / or cooling device (20) is arranged at least partially coaxially around the central axis (MA) in the sleeve section (28).

10. Device (1 ) according to one of claims 7 to 9, characterized in that the heating and / or cooling device (20) is designed and controllable in such a way that a constant temperature can be set in a sleeve space limited by the wall (30) of the sleeve section (28).

11. Device (1) according to one of the preceding claims, characterized in that the heating and / or cooling device (20) is designed as an electric heating device, in particular as a heating coil device (34), as a device for generating an electric arc (36) or as a heating ceramic (38), or that the heating and / or cooling device is designed as an optical heating device, in particular as a laser beam device.

12. Device (1) according to one of the preceding claims, characterized in that the heating and / or cooling device is designed as a fluid cooling device (40), in particular as a gas supply device.

13. Device (1) according to one of claims 3 to 12, characterized in that a gas channel system (42) with at least one outlet opening (44) is formed in the base body (21), wherein the gas channel system (42) with the outlet opening (44) is designed to supply the adhesive thread with a gas for cooling.

14. Device (1) according to one of the preceding claims, characterized in that at least one foaming device (7) is further provided for applying a foaming gas, in particular nitrogen, to the hot melt adhesive to produce a foam adhesive, and that the device is designed for applying foam adhesive to articles.

15. Packaging machine, in particular container packaging machine, comprising at least one device (1) for applying hot melt adhesive according to one of the preceding claims.

16. Packaging machine according to claim 15, wherein the at least one device for applying hot melt adhesive is configured to apply the hot melt adhesive to containers in order to produce bundles from containers joined together by means of adhesive dots.

17. Packaging machine according to claim 15 or 16, comprising a gluing station which has at least one device (1) for applying hot melt adhesive, and a setting station following the gluing station for joining the adhesive-point-provided 28 Containers for forming bundles, wherein the packaging machine preferably has an orientation device arranged in front of the gluing station for aligning the containers according to a predetermined target orientation and / or an application device arranged behind the setting station for applying a carrying handle to the bundles.

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