WO2025031863A1 - Air circulation nozzle - Google Patents

Abstract

The invention relates to a nozzle (1) for activating a coating material (5) by means of a fluid, having a nozzle body (2) with a supply-air inlet (8), a supply-air line (4) and a first outlet (3), wherein the supply-air inlet (8) and the first outlet (3) have a flow connection (7) to one another through the supply-air line (4). In order to permit energy-saving operation of a nozzle, the nozzle body has a working surface (6) with an exhaust-air inlet (9) and an exhaust-air outlet (12), wherein the exhaust-air inlet (9) and the exhaust-air outlet (12) have a flow connection (10) to one another.

Description

Description recirculation nozzle

The invention relates to a nozzle for activating a coating material and a method for activating a coating material.

Such nozzles are known per se, e.g. from WO 2017/114792 Ai or DE 10 2015 004 015 Ai. They are used to activate a coating material, e.g. edge strips for coating a workpiece, in particular a narrow surface of a panel, typically a wood-based panel, plastic or metal panel. The coating material is then pressed onto the workpiece. This process of activation, usually heating or chemical activation and coating, must often be interrupted, e.g. in order to adapt the coating material to the workpiece to be coated in terms of thickness, material or decoration. The nozzle therefore often runs in standby mode. In known models, this leads to the nozzle cooling down or to high energy consumption, which is not productive. Devices for re-collecting heated air that escapes from these nozzles are known, e.g. B. from DE 10 2020 131506 Ai, but these devices are space-consuming and complex to manufacture.

It is therefore an object of the invention to propose a nozzle and a method for activating coating material that enables energy-saving operation of a nozzle.

This object is achieved with a nozzle according to claim 1 and a method according to claim 13.

The nozzle according to the invention for activating a coating material by means of a fluid has a nozzle body with

- a supply air inlet,

- a supply air line, and - a first outlet, wherein the supply air inlet and the first outlet are in flow connection with the supply air space, characterized in that according to a first alternative the nozzle body further comprises

- a first exhaust air inlet and

- a first exhaust air outlet, wherein the first exhaust air inlet and the first exhaust air outlet open into a working surface of the nozzle body and are in flow connection with one another via a first exhaust air line and/or according to a second alternative, the nozzle body further has a second exhaust air inlet which is in flow connection with a second exhaust air line in the nozzle body, and that the nozzle body has a second exhaust air outlet which does not open into the working surface and which is in flow connection with the second exhaust air line.

Both alternatives therefore provide that fluid that has escaped, usually at a temperate level, i.e. mostly heated, is returned to the nozzle body so that the latter remains at a constant temperature. In principle, the fluid can also be cooled, but in practice it is usually heated to temperatures above ambient temperature, advantageously up to 1,500 °C. An essential feature of the nozzle according to the invention is that at least one first inlet for exhaust air is provided, which at least partially takes in the exhaust air that exits from the first outlet for the fluid. This exhaust air usually no longer has the temperature that the heated fluid has when it exits the first outlet. However, in the case of a heated fluid, it still has a temperature that is significantly above the ambient temperature, or in the case of a cooled fluid, it still has a temperature that is significantly below the ambient temperature and which is used according to the invention to temper the coating material, the workpiece and/or the nozzle body. The repeated impact of the fluid on the coating material to be activated means that the energy used to activate the fluid, in this case to heat it, which was previously released into the environment, is better utilized. The nozzle according to the invention is extremely compact and space-saving, so that no heat energy is lost through transport routes for the exhaust air. The nozzle according to the invention provides for Preferably, no reheating or cooling of exhaust air is required. However, it is fundamentally possible to provide means for heating or cooling the exhaust air, for example means for heating or cooling the first and/or second exhaust air line in order to maintain, increase or reduce the temperature of the exhaust air. An unexpected advantage of the nozzle according to the invention is that it is particularly quiet during operation compared to known nozzles. This is a considerable advantage from the point of view of occupational safety. A further advantage of the nozzle according to the invention is that existing nozzles on devices for coating workpieces can be easily replaced by the nozzle according to the invention, since the nozzle according to the invention has a compact design with small dimensions.

The entry of the exhaust air, i.e. the fluid that has exited the first outlet and is usually heated and under pressure, into the first exhaust air inlet is supported in the operating state by the coating material being guided directly in front of the work surface. The coating material is advantageously guided between a lower and an upper guide. The upper and lower guides can be separate guides. However, a guide element that has an upper and a lower guide in particular is preferred in order to be able to process coating material of different widths. The upper guide is preferably adjustable in height so that coating material of different widths can be processed. The guide or the guide element is advantageously guided on the nozzle body, e.g. by the guide element engaging behind at least one edge of the nozzle body in sections. The guide element can also cover the outlet for the supplied fluid and/or the outlet(s) for exhaust air in sections, either on the work surface or in the nozzle body, e.g. in the supply air or exhaust air lines. The height adjustment for the guide can be arranged separately from the nozzle and the device to which the nozzle is attached. Preferably, however, the height adjustment of the guide is connected to the nozzle or the device for coating the workpiece. According to a first alternative, the height adjustment is possible by means of a spindle, which is connected in particular to the upper guide. According to a second alternative, the guide for the coating material is connected to the device for coating and is automatically adjusted, e.g. via a lever or lever and joint arrangement, depending on a Edge height of the workpiece to be coated. The width of the coating material is adjusted to the edge height of the workpiece so that the entire narrow surface of the workpiece is covered by the coating material.

A guide can be designed with a flat surface that preferably rests on the narrow side or that advantageously at least partially rests on the outside of the coating material that faces away from the nozzle. A guide can, however, also advantageously be designed at an angle, so that a first section of the guide element rests on the narrow side and a second section of the guide element rests at least partially on the outside of the coating material. The guide element preferably only rests on the upper and/or lower narrow surface of the coating material in order not to damage the surface that is on the outside after coating. The coating material is advantageously guided between the guide and the work surface so that a defined distance from the work surface can be set; alternatively, the distance can be "zero".

In standby mode, the return of the exhaust air to the first and/or possibly second exhaust air inlet is preferably supported by the guide having a cover element that is plate-shaped and that is pressed against the work surface in standby mode, e.g. by spring pressure, by a piston-cylinder arrangement or the like. The cover element is advantageously designed such that it is aligned parallel to the work surface and covers it at least in sections, wherein it preferably covers at least the first outlet for the fluid and/or rests against an upper and a lower end of the work surface or against an upper and a lower end of the outlets for fluid and exhaust air as well as the inlets for the exhaust air; it can be U-shaped, for example. The cover element can also cover the work surface completely.

The cover element can have an inlet opening for the fluid and an exhaust air outlet and optionally an exhaust air duct for the fluid connected to it. In standby mode, the exhaust air emerging from the cover element can be directed in any direction through this exhaust air duct, e.g. away from the nozzle, but also back into the nozzle, e.g. in the direction of an exhaust air inlet. The exhaust air duct can be be designed according to the requirements of the respective nozzle or device for coating workpieces. The cover element can have at least one seal, which advantageously rests in standby mode on the nozzle body, in particular completely or partially on the work surface, at least the first outlet for the fluid or the area around the work surface.

In standby mode, the fluid exits the first outlet, hits the cover element or is collected in the inlet opening and is guided to the exhaust air outlet of the cover element, where the fluid either exits into the environment or is transferred to the exhaust air duct, which optionally allows the fluid to be returned to the nozzle or to exit the fluid at any point.

According to an alternative design, the cover element has a fluid channel that extends from an inlet opening that is opposite the first outlet to an outlet opening that is opposite the second exhaust air outlet of the nozzle body. The fluid is guided from the first outlet of the nozzle body through the cover element in the direction of the second outlet. The exhaust air then exits from the outlet opening of the cover element and into an exhaust air inlet of the nozzle body. The fluid then advantageously exits from an exhaust air outlet that does not open into the working surface of the nozzle body. This design of the cover element, which enables the fluid to be returned to the nozzle body, is particularly preferred if the nozzle body is to remain at a constant temperature in standby mode, i.e. if newly supplied coating material is to be reactivated as quickly as possible and without loss of performance. The cover element can be designed as a separate component, but it can also preferably be part of the guide element.

Alternatively, the advantage of a cover element is that, when it is in close contact with the working surface of the nozzle body in standby mode, the exhaust air is completely captured and diverted and that, particularly when the cover element is not completely sealed against the working surface, a suction is created that draws ambient air into the space between the cover element and the nozzle body, so that the cover or guide element and the surrounding device are cooled. The undesirable heating of the device and the area around the nozzle body, In particular, the cutting knife for the coating material and the pressure roller are avoided with minimal effort.

As described above, the exhaust air in working mode can pass one after the other through one or more first exhaust air inlets and outlets that open into the working surface and the connecting exhaust air lines in the nozzle body and then pass through an exhaust air inlet whose associated exhaust air outlet is not in the working surface of the nozzle body and thus leave the nozzle body at a freely selectable location. In working mode, the cover element is arranged at a distance from the working surface, typically up to 15 mm, preferably up to 10 mm, advantageously up to 5 mm, so that the coating material can be guided past the working surface between the cover element and the nozzle body. In the simplest case, switching between working and standby mode is done manually, but preferably automatically, e.g. via a pressure piston or a spring that controls the position of the cover element.

According to a further preferred embodiment, a guide element is used with an outer surface facing the nozzle body with at least two recesses and a closed guide space adjacent to the outer surface. The outer surface can preferably also serve as a cover element in standby mode, in particular as a spring-loaded cover element or a cover element that can be moved by a servomotor, which is guided close to the outside of the coating material in the operating state, i.e. is advantageously opposite it at a distance of up to 10 mm, preferably up to 5 mm, advantageously up to 0.1 mm. The outer surface has at least two recesses for exhaust air, namely a third exhaust air inlet that is opposite the first outlet for the fluid and directs the exhaust air into the guide space, and a third exhaust air outlet that is opposite the first and/or second exhaust air inlet and directs the exhaust air into one or more of these exhaust air inlets. The exhaust air is guided through a third exhaust air line that connects the third exhaust air inlet with the third exhaust air outlet. This design makes particularly effective use of the exhaust air in standby mode to temper the nozzle. The advantage of this design is the short distances between the outlet of the fluid and the inlet or re-entry of the exhaust air into the nozzle. The exhaust air hardly loses or gains any heat energy or temperature outside the nozzle body. Optionally, the exhaust air can also be heated or cooled when passing through the third exhaust air line.

It has been found to be a particular advantage of the invention that exhaust air which emerges from an exhaust air outlet of the nozzle body during operation can also be advantageously used for tempering, i.e. for preheating or precooling the coating material and/or the narrow side of the workpiece to be coated: During operation, the coating material, which can comprise a single- or multi-layer, preferably adhesive-free, in particular heat-activatable plastic or alternatively an adhesive-coated material, in particular a material coated with hot melt adhesive, is guided past the work surface at a distance of maximum 10 mm, advantageously at a distance of less than 5 mm, preferably at a distance of 0.1 mm or less. The smaller the distance between the coating material and the work surface, the better. The coating material is advantageously guided between a lower guide and an upper guide, the upper guide preferably being height-adjustable. The fluid emerging from the first outlet, usually heated and generally under pressure, or the exhaust air emerging from the first exhaust air outlet, which is still at a temperature above room temperature, impacts directly on the coating material, with thermal energy being exchanged between the fluid or the exhaust air and the coating material. When heating, energy is transferred from the fluid to the coating material, while when cooling, energy is transferred from the coating material to the fluid. In connection with the invention, heat energy is usually mentioned which is transferred from the fluid to the coating material, but cooling of the coating material is always also meant. In the working direction, exhaust air first hits the coating material and only then does the usually heated fluid which emerges from the first outlet. While the heat energy of the heated and pressurized fluid at the first outlet is so great that the surface of the coating material is fully activated, i.e. usually softened or melted, the impact of exhaust air probably only causes the coating material to be preheated. If the usually heated fluid hits a coating material preheated by exhaust air, less heat energy is than is required to activate a non-preheated coating material. The energy saved advantageously leads to a lower use of fluid or to a higher feed rate of a coating device in which the nozzle is inserted.

Optionally, the coating material can be pressed towards the nozzle body during operation using a spring, e.g. a leaf spring. Since activation using a heated fluid works better the smaller the distance between the outlet for the fluid and the surface to be activated, the spring contributes to optimal activation of the coating material.

The fluid that is usually heated is either a gas, preferably air, or a gas-liquid mixture, for example air enriched with water, whereby the fluid is usually under pressure. Compressed air or compressed air enriched with water is preferably used for activation, in this case for heating the coating material. Alternatively, other gases, e.g. nitrogen, can also be used and other liquids, e.g. acidic or alkaline solutions or liquids that chemically activate the coating material, can be used. The fluid is preferably heated to temperatures of approx. 250 °C to 1,500 °C. In the operating state, it is usually under a pressure of up to 10 bar; in general, the pressure can be selected as high as the material of the nozzle body allows. It has been found to be an unexpected advantage of the nozzle according to the invention that the coating material can be activated with an average of only up to approx. 50%, advantageously approx. 40%, of the amount of fluid usually used. For example, instead of around 1,0001/min of compressed air, only up to 5001/min of compressed air is required to activate the coating material. This saving not only reduces operating costs but also investment costs because a correspondingly small compressor is sufficient to provide the required fluid. Alternatively, only one compressor is required instead of the previous two compressors.

The nozzle body is preferably made of metal, but can also be made of a ceramic material, glass or another material, provided that the material can withstand the operating pressure of the heated and usually pressurized fluid and the respective operating temperature of e.g. up to 1,500 °C. The nozzle body is advantageously manufactured using an additive manufacturing process, particularly 3D printing. This process enables loss-free production of even complex structures. Nozzles manufactured using 3D printing are also lighter and therefore use less material.

The nozzle according to the invention has an air supply inlet for the heated and generally pressurized fluid and a first outlet, which are flow-connected to one another by an air supply line. The air supply line is designed such that the heated fluid exits the first outlet with as little change in temperature and pressure as possible. The first outlet is arranged in a working surface, with the area around the first outlet preferably being set back in the nozzle body by up to 3 mm, advantageously up to 0.1 mm, from the working surface. The first outlet can advantageously consist of one or more openings, with the individual opening having a mostly round or oval outlet and an elongated section, advantageously 5 mm to 15 mm long, set back from the working surface in the manner of a keyhole, which extends against the working direction. The first outlet can also have two or more rows of openings. In the operating state, the mostly heated fluid emerges directly from this first outlet, i.e. i.e., at a distance of a maximum of 10 mm, preferably at a distance of up to 1 mm, particularly preferably up to 0.1 mm from the coating material to be activated and exchanges part of its heat and pressure energy with the coating material. After exiting the first outlet and in the operating state after hitting the coating material to be activated, it becomes exhaust air.

The working surface, an outer surface of the nozzle body, which in the operating state faces the coating material to be activated, further comprises, according to the invention, according to the first alternative, a first exhaust air inlet through which the exhaust air, i.e. the fluid which is still heated and under pressure after hitting the coating material, is returned to the nozzle body. The first exhaust air inlet is assigned a first exhaust air outlet via a flow connection, the first exhaust air line, which advantageously runs in the nozzle body, which is preferably designed so that the exhaust air is directed at an angle of 90° ± 45 ⁰ , advantageously in a Angle of 90° ± 10° hits the coating material so that the exhaust air transfers a maximum of heat energy to the coating material. According to a particularly preferred embodiment, two or more first exhaust air inlets and outlets are provided. In the operating state, the first exhaust air outlet is arranged in front of the first exhaust air inlet and this in front of the first outlet in the working direction. The coating material is presumably heated by the exhaust air, but preferably not fully activated, in particular not softened or melted.

According to a second alternative, the working surface of the nozzle has a second exhaust air inlet, which is in flow connection with a second exhaust air outlet via a second exhaust air line, which preferably runs in the nozzle body. The second exhaust air outlet is not arranged in the working surface of the nozzle. It can be arranged at any point on the nozzle. The second exhaust air line advantageously extends on or through the nozzle body in order to regulate its temperature. The second exhaust air outlet is advantageously aligned so that the escaping exhaust air heats the surface of a workpiece to be coated with the coating material, e.g. a wood-based material, plastic or metal plate. With this alignment of the second outlet, it is advantageous if the second outlet has two or more outlet openings so that different areas of the surface to be coated can be heated in a targeted manner if necessary. Individual outlet openings of the second outlet can advantageously be closed or opened individually by means of closing means.

It is clear from the above description that the first and second alternatives can each be implemented individually on a nozzle. However, they are preferably implemented together on a nozzle. In the working direction, the second exhaust air inlet is arranged before the first exhaust air outlet. The exhaust air with the least heat content is therefore fed to the second exhaust air outlet. While according to an advantageous embodiment the flow connection between the first exhaust air inlet and outlet on the one hand and the second exhaust air inlet and outlet on the other hand are separated from one another, these two exhaust air flows can optionally also be connected to one another, e.g. by an opening between the flow connection between the first exhaust air inlet and outlet on the one hand and the exhaust air line that is assigned to the second inlet and outlet. According to a particularly preferred embodiment, the nozzle body has a guide element which is arranged behind a respective first or second exhaust air inlet when viewed in the direction of the flowing exhaust air, i.e. opposite to the working direction. The guide element should guide the exhaust air as completely as possible into the first or second exhaust air inlet. The guide element extends from the rear edge of an exhaust air inlet when viewed in the direction of the flowing exhaust air at least to the level of the working surface, but advantageously up to the coating material. The guide element also advantageously extends over the entire height of the exhaust air inlet or over the entire height of the nozzle body in order to guide the exhaust air as completely as possible into the exhaust air inlet.

To ensure that the coating material is not damaged by the guide element, it is advantageously shaped as a wedge that is directed in the working direction of the coating material, i.e. against the flow direction of the exhaust air. The tip of the wedge-shaped guide element can partially cover the associated exhaust air inlet.

The exhaust air that no longer exits the work surface can, according to the invention, be discharged from the nozzle body through an exhaust air outlet at any point - and thus in all directions. It is advantageously directed from the exhaust air outlet onto the workpiece to be coated. The exhaust air line can extend through the nozzle body to the desired exhaust air outlet, e.g. in order to optimally adapt to the desired installation situation of the nozzle. Optionally, an exhaust air duct can be connected to the nozzle body, which continues the exhaust air line so that the exhaust air is either directed onto the material to be coated or away from the device to avoid heating up. The exhaust air duct can optionally have a movable element to direct the exhaust air onto the workpiece to be coated during work mode, but away from the device during standby mode. Since the exhaust air usually has a lower temperature than the supply air, the exhaust air duct can be made of the same or a different material as the nozzle body, e.g. plastic. In particular, if an additive manufacturing process such as 3D printing is used to produce the exhaust air duct, any exhaust air duct, even complex ones, can be provided that can be individually adapted to the respective are adapted to the application situation of the nozzle.

In particular, when the exhaust air outlet or the exhaust air duct is directed towards the surface of the workpiece to be coated during operation, both the workpiece is optimally prepared and the coating material is optimally activated. This is reflected in improved strength and water resistance of the welded or adhesive bond between the workpiece and the coating material, which results in a bond between the workpiece and the coating material that still exists or is improved after storage in water that is at least three times longer.

According to a further preferred embodiment, the nozzle body is double-walled. The double-walled design reduces the cooling of the nozzle body in standby mode. The release of heat from the nozzle body into the environment is also advantageously reduced.

It is considered particularly advantageous that the nozzle body of the nozzle according to the invention has a standby device with a standby inlet, a standby space and a standby outlet. The standby device is advantageously not connected to other flow connections, here e.g. the supply air line of the fluid or an exhaust air line. It is preferably designed as an independent device of a nozzle body. It can also be arranged on nozzles that do not correspond to the nozzle according to the invention. In a double-walled nozzle, the space between the two outer walls of the nozzle body can be used as the standby space, which is provided with its own standby inlet and a standby outlet. A tempered fluid, i.e. a mostly heated or cooled and usually pressurized fluid, is introduced through the standby inlet, flows through the standby space and flows out again from the standby outlet. This keeps the nozzle body tempered in standby mode. According to a particularly preferred embodiment, the standby space can pass through the nozzle body without being in flow connection with the lines for the fluid or the exhaust air. When designing the standby space, care can be taken to ensure that the nozzle body is evenly tempered. The nozzle according to the invention can be used in a device for coating workpieces, in particular for coating the narrow surfaces of plate-shaped workpieces. Such a device has means for conveying the workpiece, means for conveying the coating material, the nozzle according to the invention for at least sectional activation, e.g. for melting or liquefying the coating material, and pressure means for pressing or pressing the coating material onto the workpiece. A known disadvantage of such devices is that the heated exhaust air emerging from the nozzle heats surrounding tools such as a cutting knife for cutting the coating material to length or the pressure means for pressing the coating material onto the workpiece, usually a pressure roller. However, a heated pressure means often causes undesirable deformation and/or discoloration of the coating material because a heated pressure means also introduces thermal energy into the coating material. Coating material that is located just in front of the nozzle in the working direction can also soften or discolor. A particular advantage of the nozzle according to the invention is that by guiding the exhaust air through the nozzle, heating or warming of surrounding tools or the coating material is largely avoided. Using the nozzle according to the invention therefore results in less waste when coating workpieces with the coating material, since undesirable discoloration and/or deformation no longer occurs.

The nozzle for activating the coating material is usually arranged on the complex device for coating the workpiece. It is usually undesirable for the heated fluid used to activate the coating material to heat the device. It is therefore considered a particularly advantageous design of the nozzle if the nozzle body does not rest fully on the more complex device and thus introduces heat into this device. Accordingly, the nozzle body advantageously rests on only one, preferably two or more support points that are small in relation to the nozzle body. The support points create a distance from the device so that the nozzle body is almost completely surrounded by the ambient air. This prevents heat from being transferred to the device and keeps the heat in the nozzle body. The support points can be molded onto the nozzle body or attached as components, e.g. screwed on. They have a height of e.g. 0.5 mm to 15 mm and can be adapted to the individual requirements of the respective device.

The invention further relates to a method for activating a coating material by means of a fluid by means of a nozzle body with

- a supply air inlet,

- a supply air line, and

- a first outlet, wherein the supply air inlet and the first outlet are in flow connection with each other through the supply air line, characterized in that according to a first alternative the nozzle body further comprises

- a first exhaust air inlet and

- a first exhaust air outlet, wherein the first exhaust air inlet and the first exhaust air outlet open into the work surface and are in flow connection with one another via a first exhaust air line and/or according to a second alternative, the nozzle body further has a second exhaust air inlet which is in flow connection with a second exhaust air line in the nozzle body, and that the nozzle body has a second exhaust air outlet which does not open into the work surface and which is in flow connection with the second exhaust air line, wherein the fluid flows through the supply air inlet into the supply air line and from there to the first outlet, in order to then flow as exhaust air into the first exhaust air inlet and from there to the first exhaust air outlet, according to a first alternative, and/or according to a second alternative, flow as exhaust air to a second exhaust air inlet and from there into an exhaust air line and to a second exhaust air outlet.

According to a preferred embodiment, the method according to the invention provides that in the operating state the coating material is guided directly along the work surface or at a distance of a maximum of 10 mm, preferably a maximum of 0.1 mm in front of the work surface, so that the exhaust air, after bouncing off the coating material, is guided in the direction of the nozzle body and thus in the direction of the first and/or second exhaust air inlet. In addition, a An upper and/or lower guide and optionally a pressure surface, usually an outer wall of a guide element, form an air space in front of the working surface, which creates a flow connection between the first outlet and the first or second inlet. This is supported by a guide element if necessary, as described above.

It has surprisingly been found that the fact that the fluid hits the coating material several times from the nozzle body apparently activates the material very effectively and the coating material can therefore also eliminate the previously required overhang of the coating material of 4 cm to 8 cm. When using known nozzles, it is a known problem that, particularly if the device is not set up precisely, the last 4 to 6 cm of the coating material are not sufficiently activated, so that a corresponding overhang of coating material must be provided, which is then separated as waste. This is not the case with the nozzle according to the invention, particularly if the narrow surface of the workpiece to be coated is also heated by exhaust air before coating with the activated coating material. Even the already cooled exhaust air, which no longer exits from the work surface but in the direction of the narrow surface of the workpiece to be coated, thus contributes advantageously to an optimized coating.

In the standby state, according to a preferred embodiment, a guide or a guide element is arranged in front of the work surface, either directly adjacent to the work surface, in particular if the first outlet and the first and/or second exhaust air inlet are recessed into the nozzle body by a recess, or at a short distance in front of the work surface, in any case such that the fluid emerging from the first outlet, usually heated, can be fed as exhaust air through the air space that creates a flow connection to the first or second exhaust air inlet, if possible without exhaust air losses occurring. Here too, an upper and/or lower guide and optionally a pressure surface of the guide element, in particular if they are pressed against the work surface by spring load or by the action of a servomotor, can help to limit the air space in front of the work surface. The distance between the work surface and Guide element maximum o,i mm.

According to an advantageous development of the method according to the invention, in standby mode according to a first alternative, a reduced amount of fluid, which is usually heated, is introduced into the nozzle body and passed through the first outlet, the first exhaust air inlet and the first exhaust air outlet or the second exhaust air inlet and outlet and/or according to a second alternative, fluid heated by a standby device is passed through a standby inlet into a standby space in the nozzle body and a standby outlet from the nozzle body. Here too, the first and second alternatives can be combined.

According to a further alternative, in standby mode, the fluid from the first outlet of the nozzle body can be guided through the cover element to a first fluid outlet through an opening of a cover element opposite the first outlet, in order then, according to a first alternative, to exit from the fluid outlet into a fluid channel which is formed in the cover element or adjoining it and to leave the nozzle or, according to a second alternative, to be guided back into the nozzle body.

The above-described embodiments of the nozzle according to the invention and of the method according to the invention can, as mentioned above, be freely combined with one another, depending on the requirements resulting from the nature of the fluid, the coating material and/or the workpiece to be coated.

Details of the invention are explained in more detail below with reference to drawings. They show:

Fig. 1 Cross section through a first embodiment of the nozzle according to the invention, Fig. 2 Perspective view of a second embodiment of the nozzle according to the invention,

Fig. 3 Cross section through a guide element and a nozzle according to the invention, Fig. 4 View of the guide element according to Fig. 3, Fig. 5 Side view of a guide element,

Fig. 6a Section through a third embodiment of the nozzle according to the invention in working mode,

Fig. 6b Section of the nozzle according to Fig. 6a in standby mode,

Fig. 7a Top view of a fourth embodiment of the nozzle according to the invention in working operation and

Fig. 7b Top view of the nozzle from Fig. 7a in standby mode

Fig. 1 shows a nozzle 1 according to the invention with a nozzle body 2 made of metal, ceramic, plastic or glass, whereby the respective material in this embodiment can withstand a pressure of up to 10 bar and a temperature of up to 1,500 °C. The nozzle 1 was manufactured using 3D printing.

The nozzle 1 has a first outlet 3, which here is designed in the form of several openings in the nozzle body arranged one above the other and/or next to one another. The first outlet 3 is connected to a supply air line 4, which extends perpendicular to the cutting plane and which opens into a supply air inlet outside the cutting plane.

The first outlet 3 is preferably inclined against the working direction Ai of a coating material 5, wherein the inclination strikes the coating material at an angle of 90° ± 45 ⁰ , advantageously at an angle of 90 ° ± 10 °. Inclining the first outlet in this direction has the effect of reducing the escape of exhaust air in the working direction Ai from the nozzle 1. The coating material 5 can be made of plastic, paper, veneer or other flat material. It can be single-layered or multi-layered, it can consist of a single material or of several materials which can be arranged in layers, for example. It can be coated with adhesive, in particular hot melt adhesive. The coating material 5 is preferably strip-shaped with a width of e.g. 5 mm to 70 mm and two or more layers and can be activated by heat, wherein the layer facing the nozzle 1 can preferably be activated at a lower temperature than an outer layer facing away from the nozzle. The coating material 5 is guided past a working surface 6 of the nozzle 1 in the working direction Ai, whereby the distance between the working surface 6 and the coating material 5 or a guide element is a maximum of 10 mm, preferably a maximum of 5 mm, particularly preferably a maximum of 0.1 mm, whereby a first flow connection 7 between the first outlet 3, the work surface 6, the coating material 5 or a guide element and a first exhaust air inlet 9 is ensured.

The fluid, which is usually heated and generally under pressure, is typically a gas or gas mixture such as air or nitrogen, which may be enriched with liquid. If a liquid is used, it can be water, an alkaline or acidic solution, or a solution for chemically activating the coating material. The fluid is usually heated to temperatures of up to 1,500 °C, typically between 350 °C and 650 °C; alternatively, it can be cooled. It is generally fed into the nozzle at a pressure of 0.1 bar to 10 bar. It is fed to the first outlet 3 through an air supply line 4 and exits the first outlet 3 towards the coating material 5, where it transfers heat energy and pressure energy to the coating material. The exhaust air bouncing off the coating material 5 is fed through the first flow connection 7 to the first exhaust air inlet 9, through which the exhaust air re-enters the nozzle 1. In the nozzle body 2, the exhaust air is led through a first exhaust air line 10 to a first exhaust air outlet 12. The first exhaust air outlet 12 is advantageously designed so that the exhaust air hits the coating material at an angle of 90° ± 45 ^° , preferably 90° ± 10°, in order to ensure an optimal transfer of heat and possibly pressure energy to the coating material. The nozzle 1 described here corresponds to the first alternative of the nozzle according to the invention.

In order to optimise the guidance of the exhaust air, Fig. 1 shows an optional component, a guide element 13. The guide element 13 extends from the nozzle body 2 to the coating material. It is advantageously wedge-shaped, with the wedge preferably being inclined in the working direction Ai so that it cannot cut into the coating material. By narrowing or closing the air space between the working surface 6 and the coating material 5, the exhaust air is effectively guided in the direction of the first exhaust air inlet 9. In Fig. 1, the arrangement of a first exhaust air inlet 9, a first Exhaust air line io and a first exhaust air outlet 12. This means that the exhaust air is guided through the nozzle body 2 several times and the heat and, if applicable, pressure energy contained therein is optimally utilized. An optional guide element 13 is also arranged here. The repeated arrangement is optional and is particularly useful when working at high temperatures and pressures of the fluid. The arrangement of a guide element 13 also reduces the escape of exhaust air flowing against the working direction Ai from the nozzle 1.

Fig. 1 also shows a second exhaust air inlet 14, starting from the first exhaust air outlet 12 and running against the working direction Ai. This second exhaust air inlet is in flow connection with an exhaust air line 15, which opens into a second exhaust air outlet 16. In contrast to the first exhaust air outlet 12, this second exhaust air outlet 16 does not open into the working surface of the nozzle body, but at a different point on the nozzle body 2. In the present embodiment of the nozzle 1 according to the invention, the second exhaust air outlet 16 opens at a point where the escaping exhaust air strikes the surface of a workpiece 17 to be coated, here the narrow surface of a wood-based material, plastic, glass or metal plate, and preheats it for the coating process. This explains the second alternative of the nozzle 1 according to the invention. Fig. 1 clearly shows that the first and second alternatives can be implemented both individually and together in a nozzle 1 according to the invention. It is also conceivable for the second alternative to be implemented not in a single embodiment as shown in Fig. 1, but also in multiple embodiments in a nozzle according to the invention; in particular if no guide elements are used.

Coating material 5 and workpiece 17 meet in the working direction Ai, A2 immediately after the nozzle 1 according to the invention and are connected to one another by a force P which generally acts on the coating material and is usually exerted by a pressure roller. The workpiece which is held by the coating device (not shown here) exerts a counterforce. When the nozzle 1 according to the invention is used, the pressure roller or another tool which exerts the force P is essentially no longer subject to the influence of exhaust air, so that the pressure roller or the tool no longer The same applies to the cutting knife K arranged in front of the nozzle 1 in the working direction Ai.

At the same time, the exhaust air passed through the nozzle body 2 several times causes a tempering of the nozzle body 2. This ensures that optimally heated fluid reaches the first outlet 3 or the coating material, so that an optimal connection of the coating material with the workpiece is achieved.

Fig. 2 shows a view of a second embodiment of the nozzle 1 according to the invention, in which, as in the other figures, the same reference numerals are used for the same components as in Fig. 1. The nozzle body 2 has a working surface 6. The first outlet 3 is arranged in the working surface 6, which here consists of a number of individual openings that are distributed over a height H of the working surface. While in Fig. 2 they are evenly distributed over the height H, according to an alternative embodiment not shown here they can also be distributed unevenly, e.g. at a closer distance at the upper and/or lower end of the working surface 6 and at a further distance in the middle of the working surface.

The working surface 6 also has a first outlet 3 for the fluid, which is usually heated and usually under pressure. The first supply air inlet 8 can be seen on the top of the nozzle body 2, which is in flow connection with the first outlet 3 via the supply air line 4 (not visible here).

In the work surface 6, the first outlet 3 is followed by a double sequence of the first exhaust air inlet 9, next to which the first exhaust air outlet 12 is arranged, which are connected to each other by a first exhaust air line 10. This is followed by the second exhaust air inlet 14, to which the second exhaust air line 15 and the second exhaust air outlet 16 are connected. Here, too, the second exhaust air outlet 16 is arranged outside the work surface 6.

Fig. 2 further clearly shows that the outlets 3 and 12 as well as the inlets 9 and 14 are advantageously arranged in a recess 11 of the working surface 6. The recess 11 serves to create a first flow connection 7, with which a Flow connection for exhaust air from the first outlet 3 to the first exhaust air inlet 9 is to be ensured. Preferably, the cross-section of the first flow connection is not larger than the cross-section of the first outlet or the first or second exhaust air outlet. If no guide elements 13 are used, the cross-section of the first flow connection 7 should advantageously not be larger than the cross-section of the inlets and outlets. Fig. 2 also shows that guide elements 13 preferably protrude beyond the recess 11 into the work surface 6 or slightly beyond it in order to guide exhaust air into the respectively assigned exhaust air inlet 9 or 14. The guide elements 13 narrow or close the first flow connection 7 so that the exhaust air flows as completely as possible into the exhaust air inlet assigned to the guide element 13. The nozzle 1 according to the embodiment shown in Fig. 2 also shows an optional opening 18a, which is usually designed as a threaded hole and which serves to attach a guide element (not shown here). The recess 11 relative to the working surface can be a maximum of 10 mm. However, it is preferred if the recess 11 is up to 1 mm, particularly preferably up to 0.1 mm.

Fig. 3 shows a cross-section through a third embodiment of the nozzle 1 according to the invention. This nozzle 1 has a nozzle body 2 in which an air supply channel 4 is built in, which is in flow connection with the first outlet 3, so that a tempered, usually heated and generally pressurized fluid can exit from the first outlet. Fig. 3 also shows a nozzle body 2 with a first exhaust air inlet 9 and with a second exhaust air inlet 14. The first exhaust air inlet 9 is followed by the first exhaust air line 10, which opens into the first exhaust air outlet 12. This arrangement is repeated against the working direction Ai. The exhaust air outlet 12, which is designed so that the exiting exhaust air hits the coating material at an angle of 90° ± 45°, preferably 90° ± 10°, is followed by the second exhaust air inlet 14, which is in flow connection with the second exhaust air line 15, which opens into the second exhaust air outlet 16. The nozzle 1 according to Fig. 3 thus also shows both alternatives of the nozzle according to the invention. Here too, the inlets and outlets in the work surface 6 are each arranged in an optional recess 11, while the optional guide elements 13 extend up to the work surface 6 or beyond. The guide elements 13 can rest on the coating material 5 in the operating state. Since they only heat the coating material, but not fully activated, contact between the guide element 13 and the coating material 5 is harmless.

Both in Fig. 2 and in Fig. 3, receptacles 27 for fastening elements can be seen, which can be provided at suitable locations in the nozzle body 2, in particular in an additive manufacturing process, e.g. in order to connect the nozzle to a coating device.

Fig. 3 also shows a nozzle 1 with a guide element 19, which is arranged opposite the nozzle body 2 and which is detachably or permanently connected to the nozzle body 2. The guide element 19 has an outer wall 20, which is opposite the working surface 6. A channel 21 for the coating material is formed between the working surface 6 and the outer wall 20, which is guided through this channel in the operating state. The coating material 5 is preferably located at a distance of less than 0.1 mm in front of the working surface. Fig. 3 shows the nozzle 1 with nozzle body 2 and guide element 19 in the standby state, i.e. without coating material.

To ensure that the nozzle body 2 does not cool down during standby operation, a fluid, which is usually heated and usually under pressure, is also introduced into the nozzle body through the supply air inlet 8 and flows out of the first outlet 3 through the supply air line 4. In the absence of the coating material, the outflowing fluid immediately becomes exhaust air, which enters the guide element 19 through the third exhaust air inlet 22 and passes through this in a third exhaust air line 23 to exit at a third exhaust air outlet 24. The third exhaust air inlet 22 is preferably located opposite the first outlet 3 and the third exhaust air outlet 24 is advantageously located opposite the second exhaust air inlet 14. The second exhaust air inlet 14 opens into a second exhaust air line 15, which passes through the nozzle body 2 and opens into a second exhaust air outlet 16, which is not located in the work surface 6. The exhaust air, which is passed through the nozzle body 2 in this way, tempers it and thus prevents it from cooling down or heating up. Cooling down or heating up the nozzle body 2 leads to an undesirable, extended start-up phase after starting operation, because the coating material is not immediately supplied with sufficient tempered, usually heated and generally pressurized fluid. Here too, a very short path outside the nozzle body 2 is specified for the exhaust air by the guide element 19, so that it can re-enter the nozzle body 2 with minimal heat or pressure loss. Furthermore, the heating of tools in the vicinity of the nozzle 1, e.g. the cutting blade K and pressure roller, is also advantageously avoided here.

Fig. 4 shows a guide element 19 with an outer wall 20 that is arranged essentially parallel to a work surface 6 (not shown here). This outer wall 20 serves as a cover element in standby mode. A third exhaust air inlet 22 and a third exhaust air outlet 24 are incorporated into the outer wall 20, which are in flow connection with one another via a third exhaust air line 23 in the guide element 19. The guide element 19 also has an optional opening 18b that is aligned with the bore 18a and that can be used to connect the guide element 19 and the nozzle body 2 to form a nozzle 1.

Fig. 5 shows a side view of the guide element 19. It is clear that the guide element protrudes in a contact section 25 above the outer wall 20 and, when mounted, rests against the upper area of the work surface 6, i.e. above the inlets and outlets of the work surface. This means that exhaust air cannot escape upwards. A projection 25 is arranged at the lower end of the guide element 19, or alternatively at the lower end of the nozzle body 2 in the area of the work surface 6, on which the coating material 5 is supported. The contact section 25, which is arranged above the inlets and outlets for fluid and exhaust air, serves as a guide for the upper narrow surface and preferably guides the adjacent outside of the coating material 5 in sections in connection with the outer wall 20. The projection 26, which is arranged below or at the lower end of the working surface 6, guides the lower narrow surface of the coating material 5 and, if necessary, in sections in connection with the outer wall 20, also the adjacent outside of the coating material 5. The contact section 25 and projection 26, in particular in conjunction with the recess 11, seal off the first flow connection 7 from the environment in such a way that the exhaust air can be discharged both in the presence of the coating material and in the absence of the coating material 5 can be returned to the nozzle body 2 and thus tempers the nozzle body 2.

According to a further embodiment not shown here, the outer wall 20 is spring-loaded as a cover element, possibly also as a separate component, and lies close to the work surface 6 in standby mode. Alternatively, and also not shown in Figs. 1 to 5, the guide element 19 can be moved in the direction of the work surface 6 and away from the work surface 6, e.g. either by a pressure spring or by a servomotor, so that in the operating state it creates space for the coating material 5 to pass through, while in standby mode the outer wall 20 as a cover element is brought so close to the work surface 6 that the first flow connection 7 has a cross-section that is preferably not significantly larger than that of the first flow connection in the presence of the coating material 5 present in the operating state.

Fig. 6a and Fig. 6b each show a section through a third embodiment of the nozzle 1 according to the invention. Here too, the same reference numerals denote the same components. The nozzle body 2 has a first outlet 3, which is supplied with fluid through a first supply air line 4. The first supply air line 4 extends from the first outlet 3 to the supply air inlet 8 and thus creates a first flow connection 7 for the fluid. Next to the outlet 3, the first exhaust air inlet 9 is arranged, from which a guide element 13 extends in the direction of the work surface in order to guide the exhaust air into the first exhaust air inlet 9. The first exhaust air inlet 9 is in flow connection with the first exhaust air outlet 12. The first exhaust air outlet 12 directs the escaping exhaust air onto the coating material to be activated. The angle at which the exhaust air hits the coating material can be adjusted by designing the first exhaust air outlet 12 to ensure optimal activation of the fluid. The design of the other fresh and exhaust air outlets can be designed in the same way. An optimal angle for the fluid to hit is between 80° and 100° in relation to the work surface 6. The second exhaust air inlet 14 is arranged next to the second exhaust air outlet 12. The second exhaust air inlet is in flow connection with a second exhaust air line, which is not shown here. This second exhaust air line opens into a second exhaust air outlet, which Exhaust air is directed away from the nozzle body 2, preferably in the direction of the workpiece to be coated, as shown, for example, in Fig. 1.

The fluid used for activation flows in working mode, as shown in Fig. 6a, through the supply air inlet 8 to the first outlet 3, through the first exhaust air inlet 9 to the first exhaust air outlet 12, from there to the second exhaust air inlet 12 and through a second exhaust air line away from the nozzle body 2. This guidance of the fluid is very efficient in working mode. In standby mode, when no coating material is being guided past the work surface, the fluid would flow out of the first outlet 3 and heat both the nozzle body 2 and the surrounding area, including the surrounding device parts such as a cutting knife for the coating material and the pressure roller for pressing the activated coating material onto the workpiece. This is undesirable and also represents a waste of energy.

Therefore, the third embodiment according to Fig. 6a and Fig. 6b has a piston-cylinder arrangement 29, preferably a pneumatically operated arrangement, which here is arranged above the nozzle body 2. A piston 30 of the piston-cylinder arrangement leaves the first flow connection 7 and thus the supply air line 4 free during operation according to Fig. 6a, so that the fluid can flow as described above. The piston 30, on the other hand, blocks a fluid channel 28 for standby operation, which leads the fluid not required for activation away from the nozzle body 2 to a fluid outlet 28a. The fluid outlet 28a can end at any point, depending on the requirements of the respective coating device. The fluid outlet 28a can end in the area of the coating device, it can be further away, e.g. B. end outside the building, but the heated fluid that is not needed in standby mode can also be advantageously circulated and, if necessary, fed back to the supply air inlet 8 after being heated up again.

Fig. 6b shows that the piston 30 in standby mode not only blocks the fluid channel 28, but also the supply air line 4. In this position of the piston 30, a flow connection is created between the supply air line 4 and the fluid channel 28, so that the fluid, which is at operating temperature at this time, does not enter the interior of the nozzle body 2 and heat or cool it. Rather, the fluid is preferably transferred into the fluid channel 28 before entering the nozzle body 2. According to a preferred embodiment shown here in Fig. 6a and Fig. 6b, the piston-cylinder arrangement 29 has a cooling device 31 which prevents heat or cold transfer from the fluid to the piston-cylinder arrangement 29.

The fourth embodiment of the nozzle 1 according to the invention shown in Figs. 7a and 7b also deals with the guidance of the fluid in working mode (Fig. 7a) and in standby mode (Fig. 7b). Fig. 7a shows a nozzle 1 with a nozzle body 2 and a working surface 6 in which (not visible here) a first outlet 4, a first exhaust air inlet 9, a first exhaust air outlet 12 and a second exhaust air inlet 14 are arranged, approximately as shown in Fig. 1, for example. The nozzle 1 also has an air supply line 4, which is part of the first flow connection that opens into the first outlet 3.

Furthermore, Fig. 7a shows the second exhaust air line 15, with which used fluid is guided away from the nozzle body 15 during operation, preferably in the direction of a surface of a workpiece to be coated.

A covering device 32 is arranged opposite the working surface 6 of the nozzle 1. The covering device 32 has a covering element 33 which is arranged directly opposite the working surface 6, as well as a deflector 34 connected to the covering element 33 and a piston-cylinder arrangement 35 which in turn is connected to the deflector 34.

The cover element 33 is arranged at a distance of approximately 3 mm to 15 mm, often between 5 mm and 10 mm, from the work surface 6. A contact surface 38 of the cover element 33 faces the work surface and covers at least the first outlet 3; optionally, the work surface 6 is covered completely or partially. The distance between the work surface 6 and the contact surface 38 must be sufficiently dimensioned to guide the coating material to be activated past the work surface 6 during operation.

Fig. 7b shows that the cover element 33 in standby mode on the work surface 6 and covers at least the first outlet 3, preferably part or all of the working surface 6. The contact surface 38 preferably has a seal which seals the covered area towards the contact surface 6. In a simple embodiment, the cover element 33 can be moved directly, e.g. by a piston-cylinder device or another actuating device, in the direction of the working surface 6 until it rests there. Often such direct actuation is not possible because the coating device in which the nozzle according to the invention is inserted does not offer any space for this. Therefore, the arrangement shown in Fig. 7 is often recommended, which is explained below: The distance between the cover element 33 and the contact surface 6 is closed by actuating the piston-cylinder arrangement 35, the piston of which extends. The deflector 34, which is connected to the piston at a pivot point 36, is composed of two sections which are preferably rigidly connected to one another, a first section 34a which extends from the pivot point 36 to a rotation axis 37 and a second section 34b which extends from the rotation axis 37 to the cover element 33 and is fastened to it. The extending piston of the piston-cylinder arrangement 35 causes the deflector 34 to rotate about the rotation axis 37, so that the cover element 33 closes the distance to the work surface 6 and rests against it, as shown in Fig. 7b.

In the standby state according to Fig. 7b, the fluid at operating temperature is guided through the supply air line 4, exits from the first outlet 3 and enters an opening (not visible here) in the contact surface 38 of the cover element 33. The fluid exits through an exhaust air outlet 39 of the cover element 33, either directly into the area surrounding the nozzle 1 or into an exhaust air channel, which either conveys the fluid further to another outlet at a greater distance from the nozzle 1 or back in the direction of the supply air inlet 8 of the nozzle 1, if necessary after the fluid has been heated or cooled to the operating temperature again. The shape of the deflector 34 can easily be adapted to the requirements of the respective nozzle 1 or coating device. list of reference symbols

1 nozzle 28 exhaust air duct

2 nozzle body 28a exhaust air outlet

3 first outlet (standby)

4 Supply air line 29 Piston-cylinder

5 Coating material arrangement

6 working surface 30 pistons

7 first flow connection 31 cooling device

8 Supply air inlet 32 Cover device

9 first exhaust air inlet 33 cover element

10 first exhaust air line 34 deflector

11 Return 34a first section

12 first exhaust air outlet 34b second section

13 guide elements 35 piston-cylinder

14 second exhaust air inlet arrangement

15 second exhaust air line 36 articulation point

16 second exhaust air outlet 37 rotation axis

17 Workpiece 38 Contact surface

18a Hole 39 Exhaust air outlet

18b opening

19 guide element

20 exterior wall

21 channel for coating material

22 third exhaust air inlet

23 third exhaust air line Ai working direction

24 third exhaust air outlet A2 working direction

25 Plant Section H Height

26 Vorsprung P Kraft

27 shots K cutting knife

Claims

claims 1. Nozzle (1) for activating a coating material (5) by means of a fluid, comprising a nozzle body (2) with - a supply air inlet (8), - a supply air line (4), and - a first outlet (3), wherein the supply air inlet (8) and the first outlet (3) are in flow connection (7) with each other through the supply air line (4), characterized in that according to a first alternative, the nozzle body (2) further comprises a working surface (6) with - a first exhaust air inlet (9) and - a first exhaust air outlet (12), wherein the first exhaust air inlet (9) and the first exhaust air outlet (12) are in flow connection with one another through a first exhaust air line (10) and/or according to a second alternative, the nozzle body (2) on the work surface (6) further has a second exhaust air inlet (14) which is in flow connection with a second exhaust air line (15) in the nozzle body (2), and that the nozzle body (2) has a second exhaust air outlet (16) which is in flow connection with the second exhaust air line (15) and which does not open into the work surface (6). 2. Nozzle (1) according to claim 1, characterized in that each exhaust air inlet (9, 14) is assigned a guide element (13) which supplies exhaust air to the exhaust air inlet (9, 14). 3- Nozzle (1) according to claim 1 or 2, characterized in that the first Outlet 3 and/or the first exhaust air outlet (12) are shaped so that the exhaust air exits at an angle of 90° ± 45 ⁰ relative to the working surface (6). 4. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle body (2) has a height (H), and that the first outlet (3) extends as a series of openings over a part of the height (H) of the nozzle body (2), wherein the series of openings do not extend evenly distributed over a part of the height (H). 5. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle body (2) is double-walled at least in sections in the region of its outer walls. 6. Nozzle (1) according to one of the preceding claims, characterized in that a supply air arrangement adjoins the supply air inlet (8), wherein the supply air arrangement is equipped with means for adjusting the supply air quantity. 7. Nozzle (1) according to one of the preceding claims, characterized in that a guide element (19) is provided which is pressure-loaded. 8. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle body (2) has a standby device which comprises a standby inlet and a standby outlet as well as a standby space for heated fluid. 9. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle (1) has a cover element (33) with an opening in a contact surface (38) and with a fluid outlet (39). 10. Nozzle (1) according to claim 9, characterized in that the cover element (33) has a fluid channel which is formed in the cover element (33) between the opening and the fluid outlet (39) or adjacent to the fluid outlet (39). 11. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle (i) has at least one support point which is intended for support on a device for activating coating material. 12. Nozzle (1) according to one of the preceding claims, characterized in that the nozzle body (2) is manufactured by an additive manufacturing process. 13. Method for activating a coating material (5) by means of a fluid by means of a nozzle body (2) with - a supply air inlet (8), - a supply air line (4), and - a first outlet (3), wherein the supply air inlet (8) and the first outlet (3) are in flow connection with each other through the supply air line (4), characterized in that according to a first alternative the nozzle body (2) further comprises - a first exhaust air inlet (9) and - a first exhaust air outlet (12), wherein the first exhaust air inlet (9) and the first exhaust air outlet (12) open into the work surface (6) and are in flow connection with one another through a first exhaust air line (10) and/or according to a second alternative, the nozzle body (2) further comprises a second exhaust air inlet (14) which is in flow connection with a second exhaust air line (15) in the nozzle body (2), and that the nozzle body (2) comprises a second exhaust air outlet (16) which does not open into the work surface (6) and which is in flow connection with the second exhaust air line (15), wherein the fluid flows through the supply air inlet (8) into the supply air line (4) and from there to the first outlet (3), in order to then flow into the first exhaust air inlet (9) and from there to the first exhaust air outlet (12) according to a first alternative. and/or according to a second alternative to a second exhaust air inlet (14) and from there into a second exhaust air line (15) and to a second exhaust air outlet (16). 14- Method according to claim 13, characterized in that in standby operation according to a first alternative a reduced amount of fluid is introduced into the nozzle body (2) and is passed through the first outlet (3), the exhaust air inlet (9) and the exhaust air outlet (12) or the second exhaust air inlet (14) and/or according to a second alternative fluid is passed through a standby device through a standby inlet into a standby space in the nozzle body (2) and a standby outlet from the nozzle body. 15. Method according to claim 13, characterized in that the fluid in standby mode is guided from the first outlet (3) through an opening of a cover element (33) opposite the first outlet to a fluid outlet (39), in order then, according to a first alternative, to exit from the fluid outlet into a fluid channel and leave the nozzle (1) or, according to a second alternative, to be guided back into the nozzle body (2).