EP4197643A1 - Nozzle with adjustable beam geometry, nozzle assembly and method for operating a nozzle - Google Patents

Abstract

The invention relates to a device and a method for the adjustable influencing of a fluid as it exits a nozzle outlet (4), into which a first fluid line (8) flows in an axial direction (9) and a second fluid line (10) in a cylinder wall of the swirl chamber (6 ) enter. A first fluid flow (12) flows in the axial direction towards the nozzle outlet (4) and a second fluid flow (14) enters the swirl chamber (6). The combination of the two fluid flows (12, 14) in the swirl chamber (6) causes different jet geometries, which vary between a linear full jet (32) and a conical spray (30). According to the invention, the first fluid line (8) has a valve (20, 22, 24) for adjusting the volume flow. The cross sections of the first fluid line (8) and the swirl chamber (6) match and are constant along the axial direction (9). Alternatively, the cross sections of the first fluid line (8) and the swirl chamber (6) have a diameter ratio of between 1.5 and 0.5. According to a further alternative, the cross sections of the first fluid line (8) and the swirl chamber (6) are connected via a flow-constant entry area (7) with an angle of inclination β, β' at which the fluid flow (12) does not separate from the wall. The invention also relates to a nozzle arrangement with at least two nozzles.

Description

The invention relates to a device for the adjustable influencing of a fluid when it passes into the free space from a nozzle outlet, in particular a nozzle with adjustable jet geometry, comprising a first fluid line, at least one second fluid line, a swirl chamber, into which the first fluid line runs centrally in the axial direction and the at least one second fluid line entering a cylinder wall of the swirl chamber on a tangential plane at an entry angle deviating from an axial direction in order to generate a swirling flow which is oriented towards the nozzle outlet, with a first fluid flow in the first fluid line being in the axial direction flows towards a nozzle outlet and at least one second fluid flow in the at least one second fluid line on the cylinder wall enters the swirl chamber, the combination of both fluid flows in the swirl chamber causing different fluid flows depending on the difference between the volume flows of the first fluid flow and the second fluid flow Jet geometries emerge into the free space from the nozzle outlet connected to the swirl chamber, which can be varied between a linear full jet and a conical spray. The invention further relates to a nozzle arrangement, which comprises at least two nozzles, as well as a method for operating a device for the adjustable influencing of a fluid.

Hydraulic spray nozzles are used in many industrial processes, e.g. B. for cleaning, coating or cooling processes. Depending on the selected nozzle geometry, different jet shapes can be generated. While a full jet geometry generates a coherent full jet that enables large mechanical forces and mass flows in a small area, an atomizing nozzle can be used to create a droplet spray, hereinafter referred to as a spray, that wets a relatively large area in a short time. Atomizing nozzles usually have a geometry that causes an increase in turbulence and/or the creation of a swirl in the flow, so that a break-up of the jet can be induced as it leaves the nozzle exit. Measures to increase the turbulence are, for example, strong flow deflection, abrupt cross-sectional changes or a collision of several partial flows near the nozzle outlet. A swirl, on the other hand, can be generated by swirl inserts or a flow introduced tangentially into a swirl chamber. Swirl atomization allows for more uniform sprays with smaller droplets than turbulence atomization. Full jet nozzles, on the other hand, are designed in such a way that the exiting full jet remains coherent over as long a distance as possible. This can e.g. B. be realized by streamlined nozzle geometries and avoiding abrupt cross-sectional changes.

Because the jet shapes have different, sometimes conflicting properties, changing the jet shape as needed makes sense for processes with, in particular, changing process conditions and requirements in order to make the process efficient. There is potential, for example, in the cleaning of containers in industrial food production or in the cleaning of construction and vehicle parts where soiling with frequently changing and inhomogeneous properties has to be cleaned. Here are movable, z. B. rotating cleaning devices are used, for which a needs-based change in jet shape can be advantageous.

So far, however, unchangeable nozzle geometries have generally been used, which do not allow a change between spray and full jet or require additional control lines to enable the necessary switching or adjustment processes, which is particularly problematic for rotating systems. Changing the jet shape is currently mostly avoided. Instead, the beam shape is retained in different process steps and for different tasks. As a result, the process is often inefficient, as the resources of time, water and cleaning fluid are consumed excessively.

If different jet shapes are indispensable, processes are often designed in several stages and the cleaning devices are converted as required for each sub-process. This requires a lot of time and personnel to change over the nozzles or the entire cleaning device and also leads to an inefficient process.

In addition to an axial flow (fluid), it is also known to introduce a second flow (fluid or air) transversely into the axial flow in front of the nozzle outlet, which causes atomization. Atomization created by a collision of axial and transverse flows cannot achieve the physical atomization characteristics of a full cone or hollow cone nozzle become. Their atomization characteristics are based on the atomization of a flow that has previously been set in motion and does not collide with axial flows. As a result, even and finer atomization can be achieved. This concept is in the pamphlets DE 100 09 573 A1 , EP 1 885 910 B1 and WO 2004/056489 A1 tracked.

From the pamphlet DE 27 33 102 A1 a solution is known in which an axial and a transversely introduced flow collide, with the transverse flow being introduced explicitly tangentially, so that a swirl occurs. Two valves are provided for switching the flows separately. If only the axial channel is opened, the flow emerges as a full jet; if both channels are open, a spray is created. Two valves are required in order to be able to continuously adjust the partial flows, as proposed in the publication, which means that more space is required and there is a greater outlay in terms of design. With this solution, too, the tangentially introduced flow must inevitably be controlled by an additional valve in order to achieve the intended effects.

Furthermore, a solution from the publication EP 0121877 B1 known in which a tangentially introduced flow, which builds up a swirl, collides with an axially introduced flow, which reduces the swirl, in a swirl chamber. The angle of the emerging spray can be changed in the form of a hollow cone with the aid of operable valves, which are used to regulate the partial flows (and in particular also the tangentially introduced flow). According to the proposed application, however, the twist is not completely eliminated when the partial flows are superimposed, so that the resulting jet shape cannot be changed completely, but only the spray angle of the hollow cone-shaped spray can be varied. The nozzle described cannot therefore be used for processes in which extensively variable jet shapes are required.

According to another known solution, the nozzle outlet is designed to be variable in its cross section and thereby enables a variable atomization behavior when additional outlet geometries are opened or the area of the existing opening is changed. A nozzle with a variable nozzle opening is more complex to produce, more prone to failure and places higher demands on the technical implementation and use in comparison to a nozzle with a fixed outlet opening. This involves increased effort in the hygienic design, maintenance, housing and complexity of the assembly. Such a solution is in the references DE 43 24 731 A1 and DE 10 2016 203 769 A1 , where the aim is to change the volumetric flow, DE 10 2005 013 127 B4 , which has as its object a change in the direction of the spray jet, and in the references EP 0 724 913 A2 and EP 2 441 522 A2 , aimed at changing the beam shape.

The pamphlets DE 102 34 872 A1 and DE 101 49 981 A1 have two fluid lines, one of which is controllable, and which open into a swirl chamber from different angles. The jet shape emerging from the nozzle is varied by alternating control, but also by the joint entry of the fluid from both fluid lines. The axial and tangential entry of the fluid lines into the swirl chamber is also described (cf. DE 101 49 981 A1 , 2 , Paragraphs [0018]-[0021]), but the axial feed line and the swirl chamber have significant differences in diameter. Several valves, which are also designed as 3/2-way valves or 3/3-way valves, are required in order to achieve the change in jet shapes, at least in both cases there is no control over influencing the axial fluid line possible. In any case, the jet only occurs when the tangential flow is blocked and the axially introduced fluid runs through the swirl chamber with as little disruption and turbulence as possible in order to leave the nozzle as a directed jet. A superimposition of the axial flow with the tangential flow for jet generation, ie a change between spray and jet, is not provided and only leads to a "mixed form" or in this case a relatively undisturbed superimposition of (hollow) cone spray and jet occurs and thus ultimately a full cone spray. The latter is possible in particular when the swirl chamber is significantly larger than the axial orifice, since the tangential flow can flow around the axial flow on the wall of the swirl chamber relatively unhindered, without the swirl being reduced.

Other references that highlight ways to change a beam shape are the DE 10 2007 054 673 B4 with the description of a belt lubrication device and/or cleaning and disinfection system, the GB 720 859A with the description of a fire engine nozzle and the EP 0 927 562 A2 with the flat jet generation by means of a hollow jet nozzle, also for fire extinguishing purposes. Known solutions in which valves are used to affect fluid flow are from the references DE 102 59 563 A1 , DE 10 2007 054 673 B4 , EP 0 140 505 B1 , CN 206701530 UU , EP 2 059 347 B1 and DE 27 33 102 A1 known, also from the publications CN 108014935BB and DE 100 09 573 A1 . In this case, valves are always arranged either in both partial flows, so that two valves are required, or one valve is used exclusively for influencing the cross flow, the bypass. This makes the design of one valve more complex.

This also applies accordingly to the publication U.S. 3,746,262 A to, in which the swirl effect of the fluid is influenced by a lifting of the cup 30 from the annular seat 46 in the sense and in the function of a switchable valve, while the axial fluid flow alone does not or only together with the transverse flow through the valve (formed from O -Ring 22 and valve seat 24) can be interrupted.

To adjust mechanisms or valve circuits, additional control lines for signal transmission are often required or have to be operated manually. This will be in the pamphlets DE 100 09 573 A1 and EP 0 927 562 A2 disclosed. The integration of control lines or the implementation of a manual adjustment require increased effort in their technical implementation. This applies in particular to technical systems that are mobile or rotating, that have higher requirements in terms of tightness (e.g. protection against water jets) or that are out of reach for manual intervention due to the process or for reasons of occupational safety.

Another obvious and already practiced solution is the use of different nozzle geometries side by side. The two different nozzle geometries are unchangeable in their geometry, separate and next to each other, so that a simultaneous operation of spray and full jet is possible via a previously branched line or they are switched by valves or a mechanism in such a way that the fluid only flows out of one of the two Nozzle geometries exits and either a spray or a full jet is generated. The simultaneous parallel operation of different nozzles is associated with an excessively high consumption of water and cleaning liquid. The paired design of a full jet and an atomizing nozzle as well as the optional valve system require space, since the jet axes are not identical, but side by side present. As a result, a relative shift between the nozzle and the intended target would be necessary if both jet shapes are to be directed at the same target one after the other. This increases the design and control effort with regard to local targeting accuracy.

It is therefore the object of the present invention to offer a nozzle, a nozzle arrangement and a method for operating the nozzle in order to achieve a simple possibility of controlling the jet shape of the fluid exiting the nozzle.

The object is achieved by a device for the adjustable influencing of a fluid as it passes into the free space from a nozzle outlet, comprising a first fluid line, at least one second fluid line and a swirl chamber. The first fluid line enters the swirl chamber centrally in the axial direction and the at least one second fluid line enters in a cylinder wall of the swirl chamber on a tangential plane at an entry angle deviating from an axial direction. This is done to create a swirling flow oriented toward the nozzle exit. A first fluid flow flows in the first fluid line in the axial direction towards a nozzle outlet. At least one second fluid flow enters the swirl chamber in the at least one second fluid line at the cylinder wall. The combination of both fluid flows in the swirl chamber causes different jet geometries to exit into the free space from the nozzle outlet connected to the swirl chamber, depending on the difference between the volume flows of the first fluid flow and the second fluid flow. The jet geometries can be varied between a linear full jet and a conical spray. According to the preferred embodiment, the cone-shaped spray emerges from the nozzle outlet as a full cone, with a hollow cone being provided according to an alternative embodiment.

According to the invention, the first fluid line has a valve for adjusting the volume flow of the first fluid flow that reaches the swirl chamber. This makes it possible to control the jet shape with a single valve and to initiate the change between full jet and spray. Surprisingly, it has been shown that influencing the first fluid flow is sufficient to bring about the change between full jet and spray. An additional influencing of the second fluid flow is not required. As a result, the device according to the invention be designed as a compact and simple nozzle with a single valve. The valve is also preferably designed as a simple 2/2-way valve that is sufficient for the desired function.

Furthermore, according to a first alternative, it is provided that the diameter of the axial channel, the first fluid line, is equal to the diameter of the swirl chamber and the cross section across the first fluid line and the swirl chamber, viewed in the axial direction, is constant. As a result, the axial flow is not impeded and no geometry-related turbulences or pressure losses are generated during or until the axial flow enters the swirl chamber. According to a second alternative, the cross sections of the first fluid line and the swirl chamber are different and have a diameter ratio, the ratio of the diameter of the first fluid line to the diameter of the swirl chamber, between 1.5 and 0.5, preferably between 1.3 and 0.7 or more preferably between 1.1 and 0.9.

If the cross sections of the first fluid line and the swirl chamber are different, it is alternatively or additionally provided that the different cross sections of the first fluid line and the swirl chamber are connected via a flow-constant entry area with an angle of inclination β or β′. The consequence of this is that the first fluid flow does not separate from the wall in the case of a laminar flow type, but instead flows laminarly along the wall and thereby eliminates the swirl of the incoming second fluid flow particularly effectively and with little loss.

• Querschnittsfläche aller zweiten Fluidleitungen (je größer, desto stärker wird der Drall reduziert);
• Anzahl der zweiten Fluidleitungen (bei gleicher Querschnittsgesamtfläche reduziert eine zweiten Fluidleitung den Drall stärker als zwei zweite Fluidleitungen);
• Eintrittswinkel α - Eintritt der zweiten Fluidleitung in die Zylinderwand der Drallkammer (je steiler der Eintrittswinkel α bzw. je näher an 90°, desto stärker wird der Drall reduziert im Vergleich zu flacherem Eintrittswinkel α, z. B. 60°);
• Länge des Abschnitts an der Düsenmündung mit kleinstem Durchmesser (je länger, desto mehr Reibung mit der Wand und desto stärker wird der Drall reduziert);
• Durchmesser des Düsenaustritts (je kleiner, desto stärker beeinflusst die Wandreibung die austretende Strömung und desto stärker wird Drall reduziert).

The borderline case for the diameter ratios at the limits of the areas specified above no longer depends primarily on the diameter ratio between the swirl chamber and the first fluid line as the areas are enlarged further, but also on the remaining nozzle geometry, which also has an influence, as there are others geometric variables can reduce or contribute to the elimination of the twist. These are e.g. e.g.:

• Cross-sectional area of all second fluid lines (the larger, the more the swirl is reduced);
• Number of second fluid lines (with the same overall cross-sectional area, one second fluid line reduces the swirl more than two second fluid lines);
• Entry angle α - Entry of the second fluid line into the cylinder wall of the swirl chamber (the steeper the entry angle α or the closer to 90°, the more the swirl is reduced compared to a flatter entry angle α, e.g. 60°);
• length of the section at the nozzle mouth with the smallest diameter (the longer, the more friction with the wall and the more the swirl is reduced);
• Diameter of the nozzle outlet (the smaller, the more the wall friction influences the exiting flow and the more the swirl is reduced).

The value of the spray angle γ is an indication of how much the swirl was reduced on the way through the nozzle under otherwise constant conditions (pressure, etc.): The smaller the angle at the exit, the more the swirl inside the nozzle was reduced.

This means that for a nozzle with a small diameter of the nozzle outlet, the swirl is already greatly reduced by this alone, so that even a rather unfavorable diameter ratio for the swirl chamber to the first fluid line of approximately 0.3, for example, results in the swirl nevertheless occurring when the first fluid line is switched on is completely eliminated, which would not have been the case with a larger outlet diameter. A small nozzle outlet diameter also leads to an overall smaller spray angle γ during spray operation, which then has to be accepted. All of the geometric variables specified above thus influence the twist both in jet and in spray operation, regardless of the valve position.

The features according to the invention, the diameter ratio of the swirl chamber to the first fluid line or the flow-constant transition, however, only have a swirl-reducing effect in jet operation, since the first fluid line is only open here. This means that the rest of the nozzle geometry can be designed favorably so that the swirl is hardly reduced and large spray angles are made possible when the spray emerges. As a result, it becomes possible to spray a large area and produce smaller, finer droplets that lead to better wetting behavior.

Even if the elimination of swirl can be achieved particularly efficiently with a laminar flow, which also minimizes pressure losses, it has surprisingly been shown that the device according to the invention can still make the change between the spray and the full jet when the flow is no longer laminar. Higher pressures result in higher flow velocities inside the nozzle, so that the critical Reynolds number is exceeded and the flow becomes turbulent. The elimination of swirl also takes place in the area of turbulent flows, with a successful change to the full jet being completed. Preventing flow separation, which causes turbulence, is advantageous, but not absolutely necessary for the elimination of swirl.

• Variante 1: konstante Querschnitte (entspricht einem "Neigungswinkel=0°" beim Übergang der ersten Fluidleistung in die Drallkammer);
• Variante 2: Querschnittsverhältnis erste Fluidleistung/Drallkammer mit sprunghaftem Übergang im Verhältnis 0,5... 1,5, vorzugsweise 0,7... 1,3;
• Variante 3: Übergang der ersten Fluidleistung in die Drallkammer mit dem Neigungswinkel β, β'.

In summary, twist elimination is reliable under all three basic constellations:

• Variant 1: constant cross-sections (corresponds to an "inclination angle=0°" when the first fluid power transitions into the swirl chamber);
• Variant 2: Cross-sectional ratio of the first fluid output/swirl chamber with an abrupt transition in the ratio 0.5...1.5, preferably 0.7...1.3;
• Variant 3: Transition of the first fluid output into the swirl chamber with the angle of inclination β, β'.

According to the preferred embodiment, the full jet emerges from the nozzle outlet when the valve releases the first fluid line. On the other hand, the spray emerges from the nozzle outlet when the valve blocks the first fluid line, so that only the at least one second fluid flow enters the swirl chamber.

It has proven to be particularly advantageous if the valve is applied in accordance with the fluid pressure that is present at the inlet of the valve on its side pointing towards the fluid connection. It works pressure-dependent and is either open in a first fluid pressure range in relation to a narrow switching point pressure or a wider transition range (to be assigned to the "first fluid pressure range") of the valve and closed in a second fluid pressure range or vice versa by being closed in the first fluid pressure range and in the second fluid pressure area is open. As a result, for example, a spray occurs at low pressures below the switching point pressure and a full jet at high pressures above the switching point pressure or vice versa. In any case, the valve can be designed in such a way that it opens at the switching point pressure when the fluid pressure increases and closes when the fluid pressure falls below the switching point pressure, or vice versa.

An embodiment with a valve that always opens and closes at the same pressure, i.e. there is no hysteresis, and in which the valve starts at a first fluid pressure that is lower than the switching point pressure of the valve and in the entire first fluid pressure range is particularly preferred is closed while open from a second fluid pressure greater than the switch point pressure of the valve and throughout the second fluid pressure range. As an alternative to this, an embodiment is provided in which the first fluid pressure or fluid pressure range is higher than the second.

Alternatively, a transition area with a partially closed valve is formed between the first fluid pressure area and the second fluid pressure area in place of the switching point. A cone-shaped spray forms in the transition area.

The valve can be used in different versions, which are divided into different functional groups according to the type of preload (pneumatic, hydraulic, mechanical, inherent), the material properties of a closing body (elastic, rigid, compressible, incompressible) and the geometry (membrane-shaped, designed as a flap , slider, needle or cylinder) can be subdivided. A combination of the functional groups enables a large number of embodiments of the valve.

According to a preferred embodiment, the valve is designed as a pneumatically prestressed membrane valve which is filled with compressed air once before operation to determine a switching point pressure and is then sealed off. This is particularly advantageous because variable adjustment of the function can be achieved by changing the pneumatic pressure, and thus the switching point pressure, in the simplest case the air pressure that acts against the membrane in the valve. The switching point pressure of the valve can thus be set particularly conveniently.

As an alternative to this, the valve is designed as a valve which is preloaded with a mechanical spring arrangement which acts on a rigid closing body (such as a flap, a slide, a needle or a cylinder). In addition, an elastic closing body, as z. B. embodies a membrane, are used. Another particularly simple and robust alternative is a valve that is designed as a compressible, elastic body. Other embodiments include rigid locking cylinders that are pneumatically preloaded, move and act as a valve.

Alternatively, instead of a mechanical spring arrangement, the valve has a pair of permanent magnets that attract one another and act on a rigid or flexible closing body. The fluid pressure p overcomes the magnetic force to open the valve, allowing the first fluid flow to pass through and into the swirl chamber. Instead of using a pair of permanent magnets, the valve can also be designed with a single magnet interacting with a ferromagnetic material. The magnet is preferably a permanent magnet because it is a very simple solution. Instead, however, an electromagnet can also be used.

It has proven to be advantageous if the entry angle α of the second fluid line or of the second fluid is between 60° and 90° in relation to the axial direction. The preferred swirl chamber is also designed to be flow-constant between the point at which the at least one second fluid line enters and the nozzle exit and without significant changes in geometry or cross-section that affect the flow and without abrupt changes. Accordingly, the cross section is essentially constant over the axial length of the swirl chamber.

In a preferred embodiment, the first fluid line and the at least one second fluid line result from at least one branch, in which a fluid flow entering the nozzle via the fluid connection is divided into partial flows, the first fluid flow and at least one second fluid flow. The at least one branch is arranged in front of the valve, ie between the fluid connection and the valve. This means that only one fluid connection is necessary and there is no need for a number of fluid lines to be routed to the valve, which is also more compact and simpler in construction.

The first fluid line preferably has a larger cross section than the second fluid line. With this and above all with the ratio of the cross sections of both fluid lines it is determined that the first fluid flow leaves the nozzle outlet as a full jet without being impaired by the second fluid flow in the swirl chamber. The consideration of the cross sections is one Prerequisite for switching between the two jet forms can be achieved solely with a single valve within the meaning of the invention.

Surprisingly, it has been shown that the nozzle outlet can be designed as a known and commonly used solid jet nozzle outlet. This component can therefore be installed in the device according to the invention as a standardized, inexpensive component without having to produce a special part for the nozzle outlet. In addition, however, it has been shown that additional effects can be achieved with various different nozzle geometries.

A cross section that tapers and then widens along a radius, similar to the bell of a trumpet, referred to below as the radius nozzle outlet, has proven to be a suitable nozzle geometry. Another suitable nozzle geometry has a cross section that tapers and then widens along a chamfer, similar to a counterbore, referred to below as the chamfer nozzle outlet. With these nozzle geometries, the full jet detaches from the wall at the point with the smallest cross-section and continues to emerge as a full jet with minor losses in stability, while the spray, by gliding along the outlet geometry, radius or bevel, which widens again in the cross-section, still can achieve a larger spray angle.

The device is preferably designed as a cleaning nozzle and is provided for dispensing a cleaning liquid. As explained at the beginning, it is often necessary to change the jet shape during cleaning processes in order to be able to clean efficiently and with high effectiveness.

The object of the invention is further achieved by a nozzle arrangement which comprises at least two nozzles of the type described above. A fluid enters this via a fluid connection which is at least fluidically connected to a supply line or alternatively via separate fluid connections with an adjustable fluid pressure in each supply line to one of the nozzles.

According to the invention, at least two of the nozzle devices are as described above and have valves, each with separately adjustable switching point pressures, which can also be set differently in order to to achieve the desired function. As a result, the valves can be switched differently depending on the applied fluid pressure. The output of the solid jet and the cone-shaped spray can be varied in such a way that all or part of the devices emit the linear solid jet or the spray.

With such an application of several nozzles in parallel operation, a valve controlled by the pressure of the operating liquid, the fluid, is used and several nozzles are connected to a pressure line, the fluid line. This allows various operating states to be implemented. If all nozzles have the same switching point, all nozzles can produce either the spray or the full jet. If the individual nozzles have different switching points, there are additional operating states in which spray and full jet are generated simultaneously with different nozzles (hybrid operation). In this case, only one control line (the fluid line) is necessary in order to set the desired operating state in a targeted manner. The overall system can therefore be used even more flexibly.

For example, different cleaning processes or, in the case of different supply lines, even the use of different cleaning agents can be carried out at the same time. If the valves are designed as pneumatically preloaded membrane valves, the different switching point pressures can be preset variably and as required and also changed later.

A further solution to the object of the invention consists in a method for operating a device for the adjustable influencing of a fluid when it passes into the free space from a nozzle outlet, as has been described above. The procedure includes two different settings or process stages.

According to the invention, the linear full jet emerges in the first setting, in that the first fluid passes through the open valve and enters the swirl chamber together with the second fluid flow. Surprisingly, it was shown that the influence of the second flow in the swirl chamber does not lead to the full jet being destroyed. The collision of the fluid flows and the configuration of the nozzle geometry, in particular the taper in the nozzle outlet, mean that the swirl introduced by the second fluid flow is greatly reduced in the subsequent nozzle section and the flow ultimately exits as a full jet. An additional Influencing of the second fluid flow can therefore be omitted, which leads to a significant simplification.

In the second setting, the cone-shaped spray exits by preventing the first fluid flow through the closed valve from entering the swirl chamber and disturbing the formation of the swirl of the second fluid flow there. The swirl experienced by the second fluid flow results in the formation of the spray as the desired jet shape at the nozzle outlet.

It has proven to be advantageous if the closed valve opens at a switching point pressure when an opening pressure range is reached and the open valve is closed when the first fluid flow reaches a closing pressure range. In the intermediate range between the opening pressure range and the closing pressure range, with the intermediate range defining the switching point pressure, the process of switching the valve from the closed position to the open position or vice versa takes place. Accordingly, the switching process takes place when an opening pressure range is reached or when a closing pressure range is reached, depending on the direction in which the fluid pressure changes. From reaching the opening pressure range, the valve is opened with increasing fluid pressure and vice versa, with decreasing fluid pressure, closed from reaching the closing pressure range. This applies when the cracking pressure range is above the closing pressure range, otherwise the behavior is reversed. Thus, depending on the fluid pressure applied to the pressure-sensitive valve, as described above, the first and the second adjustment of the jet shape are ultimately achieved via the control of the first fluid flow.

The intermediate range between the opening pressure range and the closing pressure range is very small, which is why the minimal hysteresis resulting from the intermediate range can be neglected and the small intermediate range can be regarded as the switching point. An example is the low-pressure range from p=1.0 bar to p=6.0 bar, which is primarily relevant for industrial cleaning in consumer goods production. In this range, the diaphragm valve switches when the pressure of the fluid changes by p=0.1 bar, i.e. in a very small intermediate range in relation to the entire working range, which is therefore regarded as the switching point or, in relation to the fluid pressure, as the switching point pressure. Accordingly, a variant is preferred in which no hysteresis occurs and the closing pressure range directly borders the opening pressure range, so that the above-described switching point occurs, at which the switching process takes place. In this case, either the opening pressure range of the first fluid flow is above the closing pressure range or alternatively the closing pressure range is above the opening pressure range.

The first fluid flow advantageously has a higher volume flow than the second fluid flow. This can be realized at the crossing point of the lines when the flows enter the swirl chamber by choosing a suitable ratio of the line cross-sectional areas to one another. A cross-sectional area of the first fluid line that is, for example, 2.5 times to 4.2 times larger than the added circular area of all second fluid lines or the tangential bores is particularly advantageous.

In particular when sprays are generated by means of two-component nozzles, in which the fluid is mixed with a gas phase, states arise in which the spray pulsates independently periodically without the introduction of additional energy. This phenomenon, called "self-pulsation", is characterized by clearly visible and audible oscillations in the spray. The pulsating spray forms clearly recognizable structures (often described as a "Christmas tree"-like structure).

During self-pulsation, there is a periodic variation in mass flow and spray angle. In comparison to non-pulsating sprays, this enables a more uniform local distribution of the mass flow over a longer period of time and thus a larger area overall is wetted. Studies have shown that the droplet size, measured by Sauter Mean Diameter (SMD), is larger on average for pulsating sprays compared to non-pulsating sprays.

For two-substance nozzles, in which the operating liquid is mixed with a gas phase, the self-pulsation is assumed to be triggered by a periodic blocking of the gas gap by the liquid film. The phenomenon is also known for single-substance nozzles. Investigations focused in particular on spill-return or spillback nozzles, in which the fluid is introduced tangentially into a swirl chamber and part of the fluid via one or more axial Openings can flow back against the outflow direction from the swirl chamber. Strong pulsation can occur even if there is no axial opening. The cause is assumed to be that in these cases the air core, which forms inside the swirl chamber of such nozzles, becomes unstable under certain conditions and thus causes self-pulsation.

Depending on the requirements of the process, self-pulsation is regarded as a phenomenon to be avoided or as a useful one. If the focus is on atomization into the smallest possible droplets, it is not advisable to use pulsating sprays. If, however, a large-area, uniform wetting and the transfer of mechanical impact forces through the droplets to the surface being impacted are desired, self-pulsation is advantageous over non-pulsating sprays.

Since the design of self-pulsating nozzles is still the subject of current research due to the complex interrelationships, pulsating sprays in industrial processes are usually generated by valves placed in front of the nozzle in the inflow, which switch periodically and thus interrupt the liquid supply. However, this is accompanied by considerable pressure losses and, compared to self-pulsation, smaller droplet sizes are observed, so that a different atomization characteristic prevails than when using self-pulsating nozzles.

The pulsation generally occurs preferentially in the transition area. In this area, the spray angle γ of the spray without pulsation becomes increasingly smaller as the pressure increases, until the full jet is reached at a spray angle γ of 0°. In the transition area there is a pulsating spray and a pulsating solid jet. Sometimes a pulsating spray is generated first and a further increase in pressure creates a pulsating full jet. This is caused by the approaching transition of the jet shape from spray to full jet. During the pulsation, there are periodic pressure fluctuations inside the nozzle (up to 0.3 bar), so that the switching pressure point is exceeded and a full jet is created, at least for a short time.

The non-pulsating, clearly recognizable jet is always designated as the full jet and the associated fluid pressure as the switching point pressure, which allows the transition to the jet area to be recognized. The pulsating jet that occurs in the transition area, is associated with the first fluid pressure range since the transition range is a sub-range of the first fluid pressure range.

There are ranges of fluid pressure where the nozzle operated in spray mode, where only the second fluid flow enters the swirl chamber, exhibits the phenomenon of self-pulsation. The self-pulsation at the nozzle exit occurs under a pulsation pressure, a substantially constant fluid pressure in the second fluid line, which nevertheless surprisingly causes the exiting spray to pulsate. Since the effect occurs not only under a discrete fluid pressure but over a range of pressures, the pressure range in question is referred to as the pulsation pressure range. Depending on the selected nozzle geometry, there can be no, one or more such pulsation pressure ranges in which the pulsation effect occurs. There are often a maximum of two pulsation pressure ranges.

It was found that the range of fluid pressure in which self-pulsation occurred depends on the nozzle geometry, in particular the diameter of the nozzle exit and the ratio of the summed cross-sectional areas of all second fluid lines to the cross-sectional area of the first fluid line. Furthermore, the preload of the valve has an impact on the range of fluid pressure in which self-pulsation occurs.

If only the diameter of the nozzle outlet is increased for an otherwise constant nozzle geometry, for example by retooling, a tendency towards more pronounced pulsation can be achieved.

This means that the nozzle presented can be designed differently depending on the process requirements. Either the nozzle is designed so that it does not have a range of fluid pressure in which self-pulsation occurs, so that when the valve is closed only a non-pulsating spray is produced and when the valve is open a solid jet is produced. Or the nozzle is designed to have one or more ranges of fluid pressure in which self-pulsation occurs such that when the valve is closed a non-pulsating or a pulsating spray is produced depending on the operating pressure and when the valve is open a solid jet is produced.

The possibility of designing a nozzle with self-pulsation has the advantage that no additional valves are used to implement the pulsation Need to become. This also eliminates the need for additional control lines and the state of the pulsating spray can be conveniently set via the pressure line by adjusting the fluid pressure, just as it is possible to switch between spray and full jet.

In particular for cleaning processes, as is also the aim of the present invention, the use of a pulsating spray can offer advantages over a continuous spray, since some types of dirt typical of industry can be demonstrably cleaned more efficiently if the liquid hits the surface to be cleaned discontinuously. In contrast to continuous sprays, there is no stationary film flow on the exposed surface, but the amount of fluid flows off to the side after impacting the soiled surface. The amount of fluid that follows hits the dirt directly and undamped, thereby enabling the transmission of larger impact forces. The droplets, which are on average larger than non-pulsating sprays, also enable the transfer of increased impulses to the dirt. These properties of the pulsating spray have an advantageous effect in particular on soiling that can be cleaned better under the influence of mechanical forces. In the case of swellable soiling in particular, swelling processes are increasingly stimulated when using pulsating sprays thanks to the larger spray angle and more even wetting over a large area of the soiled surface. These weaken the binding forces within the dirt and also reduce the mechanical forces required for cleaning.

The nozzle according to the invention enables an adjustable change between the jet forms "spray" and "full jet" even without pulsation effects, in order to be able to use the respective jet form as required. As a result, the opening at the nozzle exit remains unchanged in terms of area and geometry, but both spray and full jet can exit. According to an advantageous development, the switching of the nozzle between the jet forms is controlled solely by the pressure of the fluid, the operating fluid (e.g. water or cleaning fluid), so that no additional control lines are necessary.

In parallel operation with several nozzles of the same type, the nozzle also allows hybrid operation of full jet and spray, especially when one of the pressure of the Operating fluid-controlled valve is used and the switching pressures of the individual nozzles are set differently, so that more than just two operating modes for the entire system can be set as required.

Particular advantages lie in the working principle of the nozzle with branching, valve and merging in the swirl chamber, whereby superimposed geometries for full jet and spray can be achieved depending on the direction of flow introduction. The spray is generated with an exclusively tangential inflow and the full jet is created with a superimposed inflow of axial and tangential inflow. The preferred embodiment of the valve enables pressure-controlled switching. The intermediate range between the opening pressure range and the closing pressure range, in which the switchover between open and closed valve takes place, or the switching point when the switchover between open and closed valve takes place hysteresis-free with practically no intermediate range worth mentioning, is determined by the geometric parameters of the nozzle or the preload of the spring element or by means of pneumatic pressure. After a one-off setting, reliable and repeatable switching takes place.

In contrast to previously known nozzles, however, a full jet is created when the partial flows overlap, which represents a decisive difference for the function and handling of the nozzle. As a result, the use of just one valve in the axial inlet is sufficient to ensure the function. In addition, the spray is realized without flow collision in the present invention, so that pressure losses caused by collision can be avoided.

Further advantages are the simple need-based change of jet form (full jet or spray), which can be controlled directly via the pressure line if a valve controlled by the pressure of the operating liquid is used. The pressure of the operating fluid, which is used to actuate the valve, is a variable that can be controlled very easily, which does not require an additional control line and therefore has advantages over electrical control lines or manual adjustment.

Due to the possibility of switching the jet shape by adjusting the pressure of the operating liquid, the nozzle can easily be retrofitted to existing devices. There are advantages in particular for devices that work mobile or rotating, such as rotating cleaning devices or robots, which have higher requirements in terms of tightness (e.g. jet water protection) or are out of reach for manual intervention due to the process or for reasons of occupational safety.

Since the jet shape is switched over in a very small pressure range according to the particularly preferred embodiment, this can be regarded as a switching point that has advantages for the industrial design of the system according to the invention, since the entire adjustable pressure range can be used as a process window. There are practically no pressure ranges that cannot be used for the process due to switching, because there is always a spray or full jet.

The desired switching pressure can be set very easily by changing the preload of the valve or the nozzle geometry (e.g. nozzle diameter) once. After that, switching is always reliable and repeatable at the same switching point pressure.

In addition to the special geometries described above, commercially available solid jet nozzles can be used as the nozzle outlet, which can be easily exchanged if the geometric properties of the nozzle outlet, for example the nozzle diameter, are to be changed.

Since the atomization when generating the spray is based on a swirling flow, similar atomization properties can be generated as with industrial, also swirl-based full cone nozzles or hollow cone nozzles. Uncontrolled atomization or pressure losses, as with atomization due to the collision of two flows, are thus avoided. Known nozzles usually emit a spray that has the shape of a hollow cone. With the invention, on the other hand, the spray regularly has the shape of a full cone, with the result that the entire surface is wetted evenly overall.

As an alternative to the shape of a full cone, however, the shape of a hollow cone can also be aimed at, if this is desired. A hollow cone is achieved by making the cross section of the tangential flow very small or the taper at the nozzle exit very short, which would correspond to the design guidelines for hollow cone nozzles. Fundamentally allows a hollow cone opposite a full cone atomizes the spray into even smaller droplets because there is more opportunity for the droplets to interact and rub with the surrounding air. It is also planned to use appropriately designed nozzles to switch between the hollow cone and the solid jet, in order to combine the advantages of both jet shapes and use them alternately.

Parallel operation with several nozzles, each of which has different switching points, enables other operating states in addition to spray and full jet, in which spray and full jet are generated simultaneously with different nozzles (hybrid operation). As before, only one control line, the pressure line for supplying the fluid, is necessary in order to set the desired operating state in a targeted manner. This allows many new applications for an overall system in which the nozzles are embedded.

Another advantage lies in the fact that there is only one nozzle outlet, the geometry of which cannot be changed. The jet axes of both jet forms are identical, so that no relative displacement between the system and the aimed local target has to be made and calculated, as is the case when a local target is to be hit successively with both jet forms of a nozzle. If a valve that opens at high pressure is used, a spray can be generated at low operating pressure and a full jet at high operating pressure. This has particular advantages for processes in which large mechanical forces are to be transmitted with the solid jet. This primarily includes cleaning processes.

• Fig. 1: schematisch eine längs geschnittene Ansicht einer Ausführungsform einer erfindungsgemäßen Düse mit einem längs und einem quer geschnittenen Detail;
• Fig. 2: schematisch eine längs geschnittene Ansicht einer Ausführungsform einer erfindungsgemäßen Düse mit zwei unterschiedlichen Ventilstellungen und den resultierenden Strahlformen;
• Fig. 3: schematisch eine längs geschnittene Ansicht einer Ausführungsform einer erfindungsgemäßen Düse mit zwei unterschiedlichen Ventilstellungen eines Membranventils und den resultierenden Strahlformen;
• Fig. 4: schematisch eine längs geschnittene Ansicht einer Ausführungsform einer erfindungsgemäßen Düse mit zwei unterschiedlichen Ventilstellungen eines Federventils und den resultierenden Strahlformen;
• Fig. 5: schematisch eine längs geschnittene Ansicht einer Ausführungsform einer erfindungsgemäßen Düse mit zwei unterschiedlichen Ventilstellungen eines Ventils mit kompressiblem Ventilkörper und den resultierenden Strahlformen;
• Fig. 6: schematisch drei längs geschnittene Ansichten einer Ausführungsform einer erfindungsgemäßen Düse in Doppelanordnung mit einer Fluidzuführung;
• Fig. 7: schematisch vier längs geschnittene Ansichten einer Ausführungsform einer erfindungsgemäßen Düse in Doppelanordnung mit separater Fluidzuführung;
• Fig. 8: schematisch eine geschnittene Seitenansicht einer Ausführungsform eines Düsenaustritts, ausgeführt als ein Vollstrahldüsenaustritt;
• Fig. 9: schematisch eine geschnittene Seitenansicht einer Ausführungsform eines Düsenaustritts, ausgeführt als ein Fasendüsenaustritt;
• Fig. 10: schematisch eine geschnittene Seitenansicht einer Ausführungsform eines Düsenaustritts, ausgeführt als ein Radiusdüsenaustritt;
• Fig. 11: schematisch eine geschnittene Seitenansicht einer Ausführungsform einer erfindungsgemäßen Düse und
• Fig. 12: schematisch eine Ansicht von oben einer Ausführungsform einer erfindungsgemäßen Düse.

The invention is explained in more detail below on the basis of the description of exemplary embodiments and their representation in the associated drawings. Show it:

• 1 1: schematically a view in longitudinal section of an embodiment of a nozzle according to the invention with a detail in longitudinal section and a detail in transverse section;
• 2 : schematically a longitudinal section view of an embodiment of a nozzle according to the invention with two different valve positions and the resulting jet shapes;
• 3 : a schematic longitudinal section view of an embodiment of a nozzle according to the invention with two different valve positions of a membrane valve and the resulting jet shapes;
• 4 : a schematic view of a longitudinal section of an embodiment of a nozzle according to the invention with two different valve positions of a spring valve and the resulting jet shapes;
• figure 5 1: schematically shows a longitudinally sectioned view of an embodiment of a nozzle according to the invention with two different valve positions of a valve with a compressible valve body and the resulting jet shapes;
• 6 : schematically three longitudinally sectioned views of an embodiment of a nozzle according to the invention in a double arrangement with a fluid supply;
• 7 : schematically four longitudinally sectioned views of an embodiment of a nozzle according to the invention in a double arrangement with separate fluid supply;
• 8 1: schematically shows a sectional side view of an embodiment of a nozzle outlet, designed as a solid jet nozzle outlet;
• 9 1: schematically a sectional side view of an embodiment of a nozzle outlet, designed as a chamfered nozzle outlet;
• 10 1: schematically shows a sectional side view of an embodiment of a nozzle outlet, designed as a radius nozzle outlet;
• 11 : schematically a sectional side view of an embodiment of a nozzle according to the invention and
• 12 : schematic view from above of an embodiment of a nozzle according to the invention.

1 shows schematically a longitudinal section view of an embodiment of a nozzle 1 according to the invention with a transverse section detail, the section AA, and a longitudinal section detail, the section from frame B, which illustrates what is happening in the swirl chamber 6 of the nozzle body 2. The representation was made appropriately for simplification and for a better overview of all essential lines in deviation from a standard representation by a second fluid line 10 being shown in section in the view on the left, although it is not in the centrally selected sectional plane. A swirl chamber 6 with a central section would also not show the vertical section of the second fluid line 10 in section, but only the opening of its entry into the swirl chamber 6, which would have an oval contour due to the tangential entry point when penetrating the wall of the swirl chamber 6 .

The nozzle 1 includes a fluid port 3, which is the interface to the upstream device such. B. a tank cleaner or a robot, and a nozzle outlet 4, from which the fluid flows out in the desired jet shape 30, 32, as well as a branch 16 for dividing the fluid flow into two partial flows and a combination in the swirl chamber 6 for the partial flows to flow together again. Of the two partial flows, one partial flow, the first fluid flow 12, runs approximately axially to the main flow direction along the axis direction 9, while another partial flow, the second fluid flow 14, at the branching 16 and the merging in the swirl chamber 6 is not axial to the main flow direction, here aligned perpendicularly is. The non-axial partial flow, the second fluid flow 14, runs tangentially into the junction, the swirl chamber 6, in order to generate a swirling flow for exit from the nozzle outlet 4, the desired jet shape 30, 32.

The area between the merging of the fluid flows 12, 14 in the swirl chamber 6 and the nozzle outlet 4 is preferably designed to be approximately constant in flow, without sudden changes in geometry, and preferably has a constant cross-section over the entire course until the taper is reached near the nozzle outlet 4 in the axial direction 9 on. In the case of laminar flow, the flow does not detach from the wall and remains laminar. Even for cross sections of the first fluid line 8 and the swirl chamber 6 that differ from one another, a flow-constant entry region 7 is preferably implemented, via which the first fluid flow 12 enters the first fluid line 8 into the swirl chamber 6 in laminar flow without detaching from the wall. As a result, the fluid flows smoothly and evenly into the swirl chamber 6 and thus completely eliminates the swirl, so that a full jet 32 is formed at the nozzle outlet 4 . In order to achieve this, the entry area 7 has an angle of inclination β, β′ which is selected as a function of the rheological parameters, above all the flow rate of the first fluid flow 12, so that the laminar flow maintains the laminar state.

Located between the branch 16 and the swirl chamber 6 in the first fluid line 8 is a valve 20 with which the axial partial flow, the first fluid flow 12, can either be blocked or switched through. The valve 20 preferably opens and closes as a function of a set constant preload and as a function of the fluid pressure of the operating liquid, the fluid. The nozzle outlet 4 can be designed as a commercial full jet nozzle outlet, so that available Purchased parts can be used to z. B. to be able to adjust the nozzle diameter very easily by retrofitting and using a different nozzle.

• Zustand "Spray": Das Ventil 20 ist geschlossen und nur die nichtaxiale Teilströmung, die zweite Fluidströmung 14, gelangt in die Zusammenführung, die Drallkammer 6. Die aufgrund der tangentialen Einleitung in Drall versetzte zweite Fluidströmung 14 zerstäubt am Düsenaustritt 4 zu einem Spray 30.
• Zustand "Vollstrahl": Das Ventil 20 ist geöffnet, die beiden Teilströmungen, die Fluidströmungen 12 und 14, treffen in der Drallkammer 6 aufeinander und das Fluid tritt als Vollstrahl 32 aus dem Düsenaustritt 4 aus.

The following operating states occur when the nozzle is operated individually:

• "Spray" state: The valve 20 is closed and only the non-axial partial flow, the second fluid flow 14, reaches the junction, the swirl chamber 6. The second fluid flow 14, which is caused to swirl due to the tangential introduction, atomizes at the nozzle outlet 4 to form a spray 30.
• "Full jet" state: the valve 20 is open, the two partial flows, the fluid flows 12 and 14, meet in the swirl chamber 6 and the fluid emerges from the nozzle outlet 4 as a full jet 32.

The nozzle outlet 4, which is preferably designed as a full jet nozzle outlet, is arranged on the nozzle body 2, and the nozzle body 2 also has a first fluid line 8, in which the valve 20 is inserted, and a second fluid line 10, which bridges the valve 20. For this purpose, the fluid flow entering the nozzle 1 at the fluid connection 3 is divided at the branch 16 and a part flows via the second fluid line 10 until it enters the swirl chamber 6. The second fluid line 10 enters at the entry angle α, which is 90° in the illustrated embodiment ° is, in the area of the cylinder wall of the cylindrical swirl chamber 6 a.

If the valve 20 is closed, the entire volume flow of the incoming fluid flow flows via the second fluid line 10. Since the second fluid line 10 enters the swirl chamber 6 in the area of a tangential surface, the entering second fluid flow 14 receives a twist, it flows around the Axis 9. On the tangential surface, the entry angle α is preferably set between 60° and 90°. The fluid retains its swirl when it progresses out of the swirl chamber 6 to the nozzle outlet 4 and leaves the nozzle outlet 4 there in the form of a conical spray 30 . However, as soon as the valve 20 is opened, the swirl of the second fluid flow 14 is influenced or disturbed by the first fluid flow 12 also entering the swirl chamber 6 . The jet pattern leaving the nozzle outlet 4 changes, as again in the following 2 explained in more detail.

2 shows schematically a longitudinal section view of an embodiment of a nozzle 1 according to the invention with two different positions of the valve 20 and the resulting jet shapes, the conical spray 30 and the full jet 32. The full jet 30 according to the illustration above results when the valve 20 is closed, which means that there is no flow can enter the swirl chamber 6 in the axial direction. The entire volume flow of the fluid is set into a swirl and generates the conical spray 30 with a spray angle γ when it exits the nozzle outlet 4 .

In contrast to this, the lower illustration shows the open valve 20 through which the first fluid flow 12 enters the swirl chamber 6 and influences the swirl of the second fluid flow 14 there in such a way that a full jet leaves the nozzle outlet 4 .

• das Ventil ist bei niedrigem Fluiddruck geschlossen und ist bei hohem Fluiddruck geöffnet oder
• das Ventil ist bei niedrigem Fluiddruck geöffnet und bei hohem Fluiddruck geschlossen.

The valve 20 preferably opens and closes depending on the fluid pressure of the operating liquid, the fluid. This results in possible design variants for the switching behavior:

• the valve is closed at low fluid pressure and is open at high fluid pressure or
• the valve is open at low fluid pressure and closed at high fluid pressure.

Possible design variants of the closing body of the valve 20 are a flexible, elastic membrane, a compressible closing body, a rigid closing body (e.g. flaps, sliders, needles, cylinders) or an elastic closing body, each in connection with a prestress. The valve mechanism is designed for repeatable and reliable opening and closing. The range of fluid pressure (also referred to as fluid pressure range) in which switching takes place is very small and can therefore practically be ignored as a range, so that one can speak of a switching point or switching point pressure in relation to the entire working pressure range.

• pneumatisch vorgespanntes Ventil, das einmalig vor Betrieb mit Druckluft befüllt und dann abgeriegelt wird oder
• mit mechanischer Feder vorgespanntes Ventil oder
• mittels Magnetkraft vorgespanntes bzw. geschlossenes Ventil oder
• kompressibler, elastischer Körper mit inhärenter Vorspannung.

Possible design variants for realizing the preload are:

• Pneumatically preloaded valve that is filled with compressed air once before operation and then locked or
• valve preloaded with mechanical spring or
• valve prestressed or closed by means of magnetic force or
• compressible, elastic body with inherent prestress.

• bei geringem Fluiddruck bleibt das Ventil 20 geschlossen und nur der tangentiale Teilstrom oder die tangentialen Teilströme werden zusammengeführt. Die dadurch in Drall versetzte zweite Fluidströmung 14 erzeugt am Düsenaustritt 4 eine Strahlform Spray 30 mit einem Sprühwinkel γ,
• bei hohem Fluiddruck ist das Ventil 20 geöffnet und das Fluid tritt als Vollstrahl 32 aus (entspricht Sprühwinkel γ=0°).

The preferred embodiment variant for the valve 20 has the following alternately adjustable function:

• when the fluid pressure is low, the valve 20 remains closed and only the tangential partial flow or the tangential partial flows are combined. The second fluid flow 14, which is caused to swirl as a result, generates a jet shape spray 30 with a spray angle γ at the nozzle outlet 4,
• at high fluid pressure, the valve 20 is open and the fluid emerges as a full jet 32 (corresponds to spray angle γ=0°).

The closing body of the prestressed diaphragm valve 22 is designed as an elastic diaphragm 21, with the prestressing being achieved by means of compressed air. This structure allows a simple design of the switching behavior for the industrial application of the nozzle 1.

3 shows schematically a longitudinally sectioned view of an embodiment of a nozzle 1 according to the invention with two different positions of a valve 20 with a prestressed membrane body 22 and the resulting jet shapes. In the illustration on the left, the valve 20 is closed, in which the membrane body 22 was charged with compressed air via a compressed air supply 23 . Accordingly, the first fluid line 8 is closed and all of the fluid that enters the nozzle 1 flows via the second fluid line 10 into the swirl chamber 6, where it is swirled and leaves the nozzle outlet 4 as a conical spray 30. In contrast, at the right Representation of the pressure introduced via the compressed air into the membrane body of the valve 20 is reduced to such an extent that the valve 20 opens and the first fluid line 8 opens. The fluid line 8 , which is larger than the second fluid line 10 , thus disrupts the formation of the swirl in the swirl chamber 6 , with the result that a full jet is produced at the nozzle outlet 4 .

Alternatively, to change the air pressure in the diaphragm valve 22 during operation, a space filled with compressed air can also be provided as a compressed air reservoir, the initial air pressure of which is only changed to change the operating point before the nozzle 1 is operated and remains sealed off during operation. In that case, the diaphragm valve 22 is controlled by the pressure of the fluid entering the nozzle. At a high fluid pressure p it opens, as soon as the fluid pressure p decreases below the set operating point, the membrane valve 22 (like any other valve 20 used with a preload) closes again, as shown in the illustration on the left.

Figure 4a shows schematically a longitudinal section view of a further embodiment of a nozzle 1 according to the invention with a spring valve 24, with two different valve positions of the spring valve 24 being shown, and the resulting jet shapes, conical spray 30 and full jet 32. Instead of the effects of the compressed air, as above 3 explained, a spring 25 is used here, the force of which determines the operating point of the prestressed spring valve 24 .

If the fluid pressure p overcomes the spring force, as shown in the illustration on the right, the axial first fluid flow 12 enters the swirl chamber 6 and generates the full jet 32 at the nozzle outlet 4. If the fluid pressure p falls below the operating point of the spring valve 24, then the spring valve 24 and closes the fluid flow takes its way as a second fluid flow 14 via the second fluid line 10 into the swirl chamber 6, where the swirl caused thereby leads to the exit of a conical spray 30.

At Figure 4b magnetic force is used instead of the spring force, which in the illustrated embodiment is caused and implemented as two mutually attracting magnets, a pair of permanent magnets 29. The fluid pressure p overcomes the magnetic force to open the valve 20, so that the first fluid flow 12 can enter the swirl chamber 6. Instead of a pair of permanent magnets 29, a single magnet can also be provided in interaction with a ferromagnetic material, with the permanent magnet being a very simple solution, but an electromagnet can also be used instead.

The magnet-driven valve 20 is preferably designed in such a way that a flexible membrane or the like is prestressed by two magnetic bodies which are arranged in such a way that they attract each other, in particular due to their polarity, so that the first fluid line 8 is closed . As soon as the first fluid flow 12 reaches a higher pressure, the magnetic force is overcome and the valve opens. Thus, in the illustrated embodiment, the valve is embodied as a "high pressure opening valve".

figure 5 shows schematically a longitudinally sectioned view of an alternative embodiment of a nozzle 1 according to the invention with two different valve positions of a valve with a compressible valve body 26 and the resulting jet shapes, conical spray 30 and full jet 32, as also in FIGS Figures 2 to 4 shown. In contrast to this, however, no additional means is used here that determines the working point of the valve 20, but a compressible elastic valve body 26 closes against the pressure of the first fluid flow 12 in the first fluid line 8 and thereby blocks it. If, on the other hand, the fluid pressure p exceeds the working point of the valve 20 against the force of the elastic valve body 26, the valve 20 opens and the full jet 32 emerges from the nozzle outlet 4 after the first fluid flow 12 has flown through the swirl chamber 6 axially.

6 shows schematically three longitudinally sectioned views of an embodiment of a nozzle 1 according to the invention in a double arrangement with a common fluid supply for both nozzles 1. Two nozzles are connected to the same pressure line. As a result, the same pressure p is applied to both nozzles. According to the illustrated embodiment, however, the two valves 20 have different operating points, so that a variable jet pattern can be achieved at the two nozzles 1 (nozzle A and nozzle B).

• alle Düsen befinden sich im Zustand "Spray",
• alle Düsen befinden sich im Zustand "Vollstrahl",
• Düsen befinden sich in verschiedenen Zuständen "Spray und Vollstrahl liegen gleichzeitig und nebeneinander vor".

If a valve 20 controlled by the pressure p of the fluid, the operating liquid, is used and the nozzles 1 have different switching points, the following operating states are possible for the entire system:

• all nozzles are in the "Spray" state,
• all nozzles are in the "full jet" state,
• Nozzles are in different states "spray and full jet are present simultaneously and next to each other".

The pressure line, which carries the fluid entering the nozzle, also serves as a control line, so that several states can be implemented very flexibly and easily with just one signal (pressure of the fluid).

In the illustration on the left, the pressure p at the entrance to the two nozzles 1 is in the closing pressure range, so that both valves 20 are closed and all of the fluid in enters the two swirl chambers 6 via the second fluid line 10 and generates the conical spray 30 in both nozzles 1 .

In the middle illustration, the pressure p is chosen so that it is in the opening pressure range for one of the nozzles 1 and opens the valve 20, but remains closed for the other. As a result, a full jet 32 and a cone-shaped spray 30 emerge.

If the pressure p is changed further, for example increased, a picture as shown in the illustration on the right results, where the opening pressure range of both valves 20 is reached, these are permeable and the entire fluid flow enters the swirl chamber 6 via the first fluid line 8 and the nozzle outlet 4 leaves as a solid jet 32 at both nozzles. In the illustrated embodiment, a valve 20 can be used which is closed at low pressure and open at high pressure. As an alternative to this, an inverse characteristic can also be provided, in which the valve is closed at high pressure and open at low pressure.

The parallel operation is z. B. is particularly important for container cleaning. Several nozzles 1 are operated in parallel on a rotating cleaning device that has only one pressure line.

7 shows schematically four longitudinal section views of an embodiment of a nozzle 1 according to the invention in a double arrangement with a separate fluid supply, which differs from the illustration from 6 has the consequence that the spray pattern can be set individually for both nozzles 1, depending on the fluid pressure with which the fluid hits the nozzle 1. The fluid pressure p ₁ is identified as a low fluid pressure and the fluid pressure p ₂ as a high fluid pressure, in each case in relation to the operating point of the valve 20 . In contrast to this, an alternative embodiment provides for the valve 20 to be closed at high pressure and open at low pressure.

State 1 shows the low fluid pressure p ₁ for both nozzles 1, which is below the operating point of the valve 20, so that the latter remains closed. The result is cone-shaped sprays 32 at both nozzle outlets 4. In state 2, the left-hand nozzle 1 receives the higher fluid pressure p ₂ so that the valve 20 allows the fluid flow to pass axially and a full jet 32 is produced at the nozzle outlet 4, while the right-hand nozzle 1 continues to deliver the spray 30 with the valve 20 closed. For state 3, this is exactly the opposite with respect to state 2; the pressure conditions at the entrance of the two nozzles 1 are reversed. In state 4, on the other hand, the higher fluid pressure p ₂ is present at both nozzles 1, the valve opens and both nozzles emit the full jet 32.

8 shows a full jet nozzle outlet 4 of a nozzle 1 in detail. The full jet nozzle outlet 4 is a standard component that is easily and inexpensively available. The solid jet 32 emerges from the nozzle outlet 4 (cf. Figures 2 to 7 ) off when valve 20 (cf. Figures 1 to 7 ) the first fluid line 8 releases. In contrast, the spray 30 emerges from the nozzle outlet 4 when the valve 20 blocks the first fluid line 8 , so that only the at least one second fluid flow 14 enters the swirl chamber 6 .

9 shows a bevel nozzle exit 42 and 10 shows a radius nozzle outlet 46 of a nozzle 1 in detail. With these nozzle geometries, the full jet 32 separates from the wall at the point with the smallest cross-section and continues to emerge as a full jet 32 with a slight loss of stability, while the spray 30 slides along the outlet geometry, radius or bevel, which again widens in cross-section , can achieve an even larger spray angle.

11 shows a sectional side view with details A(1) to A(5), the variants of the transition from the first fluid line 8 to the swirl chamber 6, and 12 shows a view from above of an embodiment of a nozzle 1 according to the invention. The fluid connection 3, where the fluid enters, can be seen on the left side of the nozzle body 2, followed in the direction of flow (arrow) by the branch 16 at which the fluid flows between the first fluid line 8 and the second fluid line 10 splits. A push-in fitting 17 is provided for this purpose, with which the second fluid line 10 is inserted on the nozzle body 2 . In the further course, the second fluid line 10 is designed as a media hose 11 until it re-enters the nozzle body 2 in the area of the swirl chamber 6 by means of a further push-in screw connection 17 . The nozzle outlet 4 is attached to the right-hand side of the nozzle body 2 and, in the preferred embodiment shown here, is designed as a full jet nozzle that is available as standard. According to an alternative embodiment, an inlet area 7 is provided between the first fluid line 8 and the swirl chamber 6, via which the first fluid flow from the first Fluid line 8 enters the swirl chamber 6 and its function already 1 was executed.

For the inlet area 7, in addition to the smooth transition, with identical diameters of the first fluid line 8 and the swirl chamber 6, the ratio of the diameter D8 of the first fluid line 8 to the diameter D6 of the swirl chamber 6 is shown as detail variant A(1) at 0.7 in the Detail variants A(2) and A(4) and 1.3 shown in detail variants A(3) and A(5). Diameter D8 and diameter D6 are also indicated in detail variant A(1), which has been omitted in the other representations of detail variants A(2) to A(5) and also in the associated description for the sake of a better overview.

The design of the transition to A(1) to A(5) favors an effective superimposition of the first fluid flow with the second fluid flow in the swirl chamber. The first fluid flow 12 has predominantly axial velocity components and flows through the cross section of the swirl chamber 6 as a core flow primarily in the center, coaxially to the nozzle axis, the axis of symmetry of the nozzle 1, while the second fluid flow 14 has predominantly radial velocity components and the cross section of the swirl chamber 6 primarily at the outer edge area flows radially in a circular path. An "effective superimposition" of the fluid flows 12, 14 is characterized in that the axial velocity components of the first fluid flow 12 reduce the radial velocity components of the second fluid flow 14 sufficiently so that the resulting twist in the combined fluid flow (due to e.g. additional friction losses with the wall of the swirl chamber 6) can be completely eliminated up to the nozzle outlet 4 and as a result a full jet 32 exits. "Effective superimposition" takes place in particular when the first fluid flow 12 and the second fluid flow 14 can intersect or overlap over a large area in relation to the cross section of the swirl chamber 6 .

An effective superimposition of the fluid flows 12, 14 takes place when the entry area 7 is designed as a uniform transition with identical diameters according to detail variant A(1). With its axial velocity components, the first fluid flow 12 penetrates the first fluid line 8 in its entire cross section. During the transition to the swirl chamber 6, the first fluid flow 12 remains largely unchanged due to the smooth transition, so that the first Fluid flow 12 with its axial velocity components also penetrates the swirl chamber 6 in the entire cross section. The axial velocity components of the first fluid flow 12 , which are pronounced throughout the cross section of the swirl chamber 6 , therefore superimpose the radial velocity components of the second fluid flow 14 in the edge region of the swirl chamber 6 over a large area and very effectively.

The fluid flows 12, 14 are also effectively superimposed if the entry area 7 is designed as a small jump with a ratio of the diameter of the first fluid line 8 to the diameter of the swirl chamber 6, the ratio being as shown in detail variant A(2) by way of example , is 0.7 or, as shown in detail variant A(3), is 1.3.

If, as shown in detail variant A(2), the cross section of the first fluid line 8 is smaller in comparison to the swirl chamber 6, after the first fluid flow 12 enters the swirl chamber 6, flow separation and vortices are formed. The axial velocity components of the first fluid flow 12 therefore no longer penetrate the cross section of the swirl chamber 6 in the area of separation as effectively as they did in the first fluid line 8 , but are somewhat weakened in the edge region of the swirl chamber 6 . The area on which the first and second fluid flows 12, 14 overlap and an interaction of axial and radial velocity components takes place is somewhat reduced in terms of effective interaction compared to detail view A(1), but is still effective enough to reduce the swirl so to reduce far that this can be completely eliminated up to the nozzle outlet 4 (due to z. In this case, the effectiveness of the overlay can be increased by e.g. B. the swirl chamber 6 is lengthened in the area between the inlet region 7 and the junction to such an extent that the first fluid flow 12 rests against the wall of the swirl chamber 6 until it overlaps with the second fluid flow 14 . After the flow has been created, the first fluid flow 12 with its axial velocity components penetrates the swirl chamber 6 in the entire cross section without weakening in the edge region due to separation and can superimpose the radial velocity components of the second fluid flow 14 in the edge region of the swirl chamber 6 over a large area and very effectively.

If, as shown in detailed variant A(3), the cross section of the first fluid line 8 is larger in comparison to the swirl chamber 6, flow separation and vortex formation occur before the first fluid flow enters the swirl chamber. The separation area extends into the swirl chamber 6 . The axial velocity components of the first fluid flow 8 no longer penetrate the cross section of the swirl chamber 6 in the region of the separation as effectively as in the first fluid line 8 before the separation, but are somewhat weakened in the edge region of the swirl chamber 6 . Here, too, the area on which the first and second fluid flows 12, 14 overlap and an interaction of axial and radial velocity components takes place is somewhat reduced in terms of effective interaction compared to detail view A(1), but is still effective enough to Swirl to reduce so far that this can be completely eliminated up to the nozzle outlet 4 (by z. B. wall friction) and a full jet 32 exits. As in the case of the detail view A(2), the effectiveness of the overlay can be increased by e.g. B. the swirl chamber 6 is lengthened in the area between the inlet region 7 and the junction to such an extent that the first fluid flow 12 rests against the wall of the swirl chamber 6 until it overlaps with the second fluid flow 14 . After the flow has been created, the first fluid flow 12 with its axial velocity components penetrates the swirl chamber 6 in the entire cross section without weakening in the edge region due to separation and can superimpose the radial velocity components of the second fluid flow 14 in the edge region of the swirl chamber 6 over a large area and very effectively.

A ratio of 0.7 to 1.3 of the diameter of the first fluid line 8 to the diameter of the swirl chamber 6 is particularly recommended when the diameter of the nozzle outlet 4 is between 0.85 and 3.2 mm and the ratio of the cross-sectional area of the first Fluid line 8 to cross-sectional area of all second fluid lines 14 combined is between 1.2 to 7.0.

An effective superimposition of the fluid flows 12, 14 can also be realized with an entry region 7, which is designed according to the detail variants A(4) and A(5). The inlet area 7 is designed to be flow-constant, in that the transition from the first fluid line 8 to the swirl chamber 6 is designed via the angle of inclination β (decreasing towards the swirl chamber 6) or β′ (decreasing towards the first fluid line 8, therefore increasing towards the swirl chamber 6). . The inclined transition avoids detachment of the fluid flow 12 and in the case of a laminar flow kept them in the laminar state. If a laminar and non-viscous flow flows through a cross-sectional enlargement or a diffuser (the swirl chamber 6) without separation from the wall and the angle of inclination is sufficiently flat, there are no vortices or hardly any friction losses due to turbulence. The design of a diffuser is known per se from the prior art. The opening angle is a key figure for the broadening of the flow cross section of the diffuser. For centrifugal pumps, the critical value is usually around 8° to 10°. If the opening angle is too large (supercritical diffuser), dissipation occurs due to the flow detaching from the diffuser wall, which leads to strong turbulence in the transition areas to the dead spaces. In the case of a sudden strong expansion of the cross-section, one also speaks of a "Carnot collision loss", the corresponding diffuser is called a jump diffuser. In such a diffuser, the flow comes to rest again after a distance of about eight to ten times the large diameter

When the flow detaches from the wall in the entry area 7, turbulences occur. The detailed variant A(4) shows a gradual enlargement of the cross section in the entry area 7, in which the axial velocity components decrease as the cross section enlarges. The detailed variant A(5) shows a gradual narrowing of the cross section in the entry area 7, in which the axial velocity components increase as the cross section decreases. For both cases according to the detailed variants A(4) and A(5), the axial velocity components of the first fluid flow 12 penetrate the cross section of the swirl chamber 6 very effectively, without flow separation and thus weakening of the axial velocity components in the edge region of the swirl chamber 6 occurring. The axial velocity components of the first fluid flow 12 , which are pronounced throughout the cross section of the swirl chamber 6 , therefore superimpose the radial velocity components of the second fluid flow 14 in the edge region of the swirl chamber 6 over a large area and very effectively. As a result, it becomes possible to increase the ratio of the diameter of the first fluid line 8 to the diameter of the swirl chamber 6 beyond the aforementioned limits in both directions without impairing the proper function according to the invention.

While the detail variant A(2) is actually executed in the overall representation of the nozzle 1, the detail variants A(1), A(3), A(4) and A(5) can be used as alternatives take their place in each case and take their place depending on the requirement. Requirements can be, for example, a short installation space for the nozzle or a low pressure drop.

Arranged centrally in the nozzle body 2 is the valve 20 which, in the preferred embodiment shown, has a diaphragm sleeve 28 and the diaphragm 21 . The valve 20 is held by a nozzle fitting 3 which joins the two parts of the nozzle body 2 together. A sealing ring 5 is inserted between the nozzle screw connection 3 and the nozzle body 2 .

The nozzle also has a non-return valve 18 which is also connected to the nozzle screw connection 3 via a push-in screw connection 17 . The check valve 18 is used for tool-free rapid filling of the valve with a gas such. B. compressed air, without this flowing back (locking function). Filling with compressed air is possible without tools, for venting a vent screw (not shown) is provided on the opposite side of the nozzle screw connection.

Reference List

1

device, nozzle

2

nozzle body

3

fluid connection

4

Nozzle outlet, full jet nozzle outlet

5

sealing ring

6

swirl chamber

7

entry area

8th

first fluid line

9

axis direction

10

second fluid line

11

media hose

12

first fluid flow

14

second fluid flow

16

branch

17

push-in fitting

18

check valve

20

Valve

21

membrane

22

preloaded diaphragm valve

23

compressed air supply

24

preloaded spring valve

25

spring assembly

26

compressible, elastic valve body

28

membrane sleeve

29

pair of permanent magnets

30

Spray shape Cone-shaped spray

32

Jet form full jet

42

exit breakthrough

44

bevel nozzle outlet

46

radius nozzle exit

a

entry angle

β, β'

tilt angle

g

spray angle

p

fluid pressure

Claims (15)

Device for the adjustable influencing of a fluid when it passes into the free space from a nozzle outlet (4), comprising a first fluid line (8), at least one second fluid line (10), a swirl chamber (6) into which the first fluid line (8) is located centrally in an axial direction (9) and the at least one second fluid line (10) enter a cylinder wall of the swirl chamber (6) on a tangential plane at an entry angle α deviating from an axial direction, with a first fluid flow (12) in the first fluid line (8 ) flows in the axial direction towards the nozzle outlet (4) and at least one second fluid flow (14) in the at least one second fluid line (10) on the cylinder wall enters the swirl chamber (6), the combination of the two fluid flows (12, 14) in the swirl chamber (6) causes, depending on the difference between the volume flows of the first fluid flow (8) and the second fluid flow (10), different jet geometries into the free space from the nozzle outlet (4) adjoining the swirl chamber (6). emerge, which can be varied between a linear full jet (32) and a conical spray (30), characterized in that the first fluid line (8) has a valve (20, 22, 24) for adjusting the volume flow of the first fluid flow (12), which reaches the swirl chamber (6), wherein the cross sections of the first fluid line (8) and the swirl chamber (6) coincide and are constant along the axial direction (9), or wherein the cross sections of the first fluid line (8) and the swirl chamber ( 6) have a diameter ratio between 1.5 and 0.5, preferably between 1.3 and 0.7 or particularly preferably between 1.1 and 0.9, and / or wherein the different cross sections of the first fluid line (8) and the Swirl chamber (6) are connected via a flow-constant inlet region (7) with an angle of inclination β, β', at which the first fluid flow (12) does not separate from the wall. Device according to claim 1, wherein the full jet (32) emerges from the nozzle outlet (4) when the open valve (6) releases the first fluid line (12), and the spray (30) emerges from the nozzle outlet (4) when the closed valve (20, 22, 24) blocks the first fluid line (12), so that only the at least one second fluid flow (14) enters the swirl chamber (6). Device according to Claim 2, in which the valve (20, 22, 24) operates in a pressure-dependent manner in accordance with the fluid pressure p which is present at the inlet of the valve (20, 22, 24) and in a first fluid pressure range in relation to a switching point pressure or a transition range of the Valve (20, 22, 24) is open and in a second Fluid pressure area is closed, the transition area between the first fluid pressure area and the second fluid pressure area being formed with a partially closed valve in which a conical spray (30') is formed. Device according to claim 2 or 3, wherein the valve (20) comprises a compressible and elastic valve body (26) or as a prestressed membrane valve (22) or as a spring valve (24) prestressed with a mechanical spring arrangement (25) or with a pair of permanent magnets that attract one another (29), which act on a rigid or flexible closing body, is executed. Device according to one of the preceding claims, in which the entry angle α of the second fluid line (10) is between 60° and 90° in relation to the axial direction (9). Device according to one of the preceding claims, wherein the first fluid line (8) and the at least one second fluid line (10) result from at least one branch (16), in which a fluid flow entering at the fluid connection (3) is divided into partial flows, the first fluid flow (12 ) and at least one second fluid flow (14), wherein the at least one branch (16) is arranged upstream of the valve (20, 22, 24). Device according to one of the preceding claims, wherein the first fluid line (8) has a larger cross section than the second fluid line (10) or the sum of the cross sections of the second fluid lines (10). Device according to one of the preceding claims, wherein the nozzle outlet is designed as a solid jet nozzle outlet (4), a chamfered nozzle outlet (44) and/or a radius nozzle outlet (46). Device according to one of the preceding claims, wherein the device (1) is designed as a cleaning nozzle and is provided for dispensing a cleaning liquid. Nozzle arrangement comprising at least two nozzles (1), into which a fluid enters via a fluid connection (3) connected at least in terms of flow to a supply line or via separate fluid connections for the at least two nozzles (1), each with an adjustable fluid pressure (p), characterized in that the at least two nozzles (1) are devices according to one of claims 2 to 9 and have valves (20, 22, 24) each with separately adjustable switching point pressures, so that the valves (20, 22, 24) depending on the fluid pressure (p) switched differently and the Exit of the full jet (32) and the conical spray (30) can be varied in such a way that all or part of the nozzles (1) deliver the linear full jet (32) or the spray (30). Method for operating a device for the adjustable influencing of a fluid when it passes into the free space from a nozzle outlet (4) according to one of Claims 1 to 9, comprising a first and a second setting, characterized in that in the first setting the linear full jet ( 32) exits in that the first fluid flow (12) passes the opened valve (20, 22, 24) and enters the swirl chamber (6) together with the second fluid flow (14), wherein in the second setting the cone-shaped spray (6) exits in that the first fluid flow (12) is prevented by the closed valve (20, 22, 24) from entering the swirl chamber (6) and influencing the formation of the swirl of the second fluid flow (14) there. Method according to Claim 11, in which the valve (20, 22, 24) changes its switching state at a switching point pressure or across a transition range in that it opens when an opening pressure range of the first fluid flow (12) is reached and when it reaches a closing pressure range of the first fluid flow (12 ) closes. The method of claim 12, wherein the opening pressure range of the first fluid flow (12) is above the closing pressure range. The method according to any one of claims 11 to 13, wherein the conical spray (30) or the linear full jet (32) is superimposed by a pulsation effect when the valve (20, 22, 24) is closed, the second fluid flow (14) is under a pulsation pressure . The method of claim 14, wherein the pulsation pressure extends over at least one pulsation pressure range and the pulsation changes characteristics across the pulsation pressure range.

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