WO2003090935A1 - Device for the production of an aerosol - Google Patents

Abstract

The invention relates to a device (1) for producing an aerosol (4), which is used particularly for cooling and/or lubricating aerosol consumers (5) such as workpieces or tools and/or machine components. Said device comprises a nebulizer (14) that is provided with a mixing chamber (32) in which a liquid (13) and a gas (12) are mixed to form an aerosol. The aerosol is directed from the mixing chamber (32) into an aerosol chamber by means of an aerosol outlet (38) in the form of an aerosol jet. Said aerosol jet (34) hits an impact element (21) which is disposed inside the aerosol chamber at a distance from the aerosol outlet. In order to improve the quality of the aerosol and make the device more robust, the diameter (DP) of the impact element in a plane that is located perpendicular to the spraying direction of the aerosol jet is greater at least by 20 percent of the distance between said plane and the aerosol outlet than the diameter of the aerosol jet (DS) but the maximum diameter of the impact element is such that the aerosol continues to flow therearound. Said arrangement makes it possible to produce a surprisingly fine aerosol without requiring any complicated adjustment, and the impact element centers on its own within the aerosol jet.

Description

 Device for producing an aerosol

The invention relates to a device for producing an aerosol, in particular for the cooling and / or lubrication of aerosol consumers, such as workpieces, tools and / or machine elements, with a mixing chamber, through which at least one liquid and at least one gas can be mixed with the aerosol during operation with an aerosol chamber into which the aerosol is directed from the mixing chamber through an aerosol outlet essentially in the form of an aerosol jet and from which the aerosol is directed to an aerosol consumer, and with a baffle arranged at a distance from the aerosol outlet in the aerosol chamber and onto which the Aerosol jet is directed.

Nowadays, aerosols are used for minimal quantity lubrication for cooling and lubrication in many areas of mechanical engineering, because on the one hand they lead to low consumption of coolant or lubricant and on the other hand through rotating lines, for example through a work spindle, to the lubrication point can be transported without being mechanically influenced by the centrifugal acceleration, as would be the case with oil-water emissions. However, the smallest possible particle size of the sol should be aimed for in order to transport the aerosol as efficiently as possible through such rotating lines.

There are a number of solutions in the prior art for producing the finest possible aerosol.

For example, a device is known from US Pat. No. 3,084,874 in which a gas jet flowing at supersonic speed and a separate liquid jet enveloping this gas jet are directed onto a flow obstacle, where they mix to form an aerosol.

The device of CH-259242 uses the flow of the gas along a graduated packing to mix the liquid, which is brought separately to the packing, at an edge of the packing with the gas to form an aerosol. In other devices, in particular in US 3,061, 204, US 3,171, 602, GB 166,790 and US 1, 272,274, an impact body is used to split a liquid jet directed at it into drops and to expand the liquid jet and over a larger one Distribute space, for example for use in sprinkler systems. However, no aerosol is generated here, since the sprays produced in this way contain no droplets in the form of suspended particles with a diameter of at most 100 μm.

From GB 816,992 a spraying device is known, in which in a configuration for fire extinguishers and sprinkler systems, a diffuser in the form of a stepped cylindrical block is illuminated by a liquid-air mixture. The diffuser is spaced from the outlet from which the liquid-air jet emerges. However, this device does not serve to produce an aerosol, but rather to distribute a spray with drops larger than an aerosol over as large an area as possible in order to achieve the greatest possible extinguishing effect.

WO 91/16991 describes a nebulizing nozzle without a mixing chamber for producing an aerosol, in which the liquid to be nebulized is only brought to an outlet for a gas jet from the outside at the outlet of the nozzle. At the outlet of the gas jet there is a projecting lip, through which a flow is generated, with which liquid particles are entrained, and an expanding filler body with a projecting edge is provided. The protruding edges on the outlet and on the packing serve as tear-off edges, from which liquid particles in teardrop form are entrained by the gas jet and thus generate the aerosol. At the same time, the protruding edge creates a vortex that causes large drops to deposit on the packing.

In the device of DE 196 54 321 A1, a baffle formed as a step cone is arranged in an aerosol jet, so that large drops impact and wet the baffle, while small drops flow around the baffle. At the steps of the impact body, the liquid collecting there is carried along in the form of small droplets. In the device of JP 06226145, a liquid jet is directed onto a filling body, mixing only to an aerosol taking place on the filling body.

Finally, in the device of US Pat. No. 4,637,493, a baffle plate arranged in the mixing chamber serves to separate large droplets in the aerosol.

The devices known from the prior art have the disadvantage that they only produce a fine aerosol under very controlled environmental conditions. If the operating conditions change, they produce an aerosol of uneven quality if they are not readjusted with great effort. In the known cooling lubrication devices, a change in the viscosity of the aerosol liquid can already lead to poor aerosol quality.

The present invention is therefore based on the object of providing a robust device for aerosol generation which can reliably produce an aerosol with a small droplet size over a wide range of uses without the need for complex adjustments of the device.

This object is achieved according to the invention for the above-mentioned device for producing an aerosol in that the diameter of the impact body in a plane transverse to the jet direction of the aerosol jet is at least 0.2 times the distance of this plane from the aerosol outlet which is greater than the diameter of the Aerosol jet at the aerosol outlet and at most so large that the impact body is still surrounded by the aerosol jet.

Surprisingly, tests have shown that, in contrast to the devices known from the prior art, with such an arrangement of the impact body, a uniform aerosol quality can be produced regardless of the aerosol liquids used. The flow around the aerosol jet should be such that a force is exerted on the impact body by the aerosol jet that automatically centers the impact body when it is not arranged centrally in the aerosol jet. As a result, the adjustment of the impact body in the aerosol jet is considerably simplified compared to the prior art. In particular at high speeds of the aerosol jet, it is advantageous if the diameter of the impact body is at least 0.3 times the distance from the aerosol outlet larger than the diameter of the aerosol jet at this point.

It is also advantageous if the impact body is still located in the core jet of the aerosol jet, which tapers from the aerosol outlet in a substantially conical shape. In particular, the distance of the impact body from the aerosol outlet can be at most 0.3 times the diameter of the aerosol jet at the aerosol outlet. In this configuration, particularly high restoring forces are generated by the aerosol jet.

In an advantageous development, the impact body can be designed such that the above dimensions for the diameter are also met at every point of the impact body.

Due to the configuration of the impact body according to the invention, it is possible to obtain a fine aerosol even if the impact body has an essentially smooth surface. It is therefore possible to dispense with the step structure known from the prior art, which can only be produced with great effort.

In a further advantageous embodiment, the impact body can be designed as a hemisphere facing the aerosol outlet. With this configuration, an improved aerosol quality compared to a step cone was observed in experiments. The same quality is achieved if the impact body is designed as a sphere, the configuration of the impact body according to the invention being used in this case for the hemisphere facing the aerosol outlet.

Alternatively, the impact body can also be designed as a sieve. The design as a sieve is in particular an advantageous solution per se, which can be independent of the diameter-dependent arrangement of the sieve in the aerosol jet. The mesh size of the sieve can advantageously correspond at least to the mean nominal particle size of the aerosol to be directed to the aerosol consumer. With this configuration, one can be used to supply the aerosol consumer. pass a sufficiently large aerosol flow through the sieve without negatively affecting the average particle size of the aerosol.

It is also advantageous if the mesh size of the sieve corresponds at most to 1.5 times the average target particle size of the aerosol to be directed to the aerosol consumer. Surprisingly, it has been shown that, despite a mesh size that is larger than the average desired particle size, the particle size of the aerosol to be directed to the aerosol consumer, smaller particles can nevertheless be obtained.

In a further advantageous embodiment, which can also be an invention that is independent of the diameter-dependent spacing of the impact body, a jet deflection device can be formed on the impact body, which adjoins the impact body in the flow direction of the aerosol jet and through which the aerosol is deflected such that the Aerosol is specifically mixed in the aerosol chamber by the aerosol jet. The beam deflection section can be configured as a baffle plate and / or as one piece with the impact body or as a separate part or body.

The deflection section essentially serves for the flow-technically favorable deflection of the aerosol jet in one direction, which leads to a large-scale circulation flow in the aerosol chamber and avoids stagnation areas in which the flow velocity essentially rests the aerosol in the aerosol chamber. The circulating flow can be designed in the form of large vortices which extend through the aerosol chamber and are driven by the deflected aerosol jet. In this advantageous embodiment, the aerosol accumulating in the aerosol chamber is constantly mixed by the aerosol jet, so that agglomeration of the aerosol drops in the aerosol chamber is avoided.

This embodiment can advantageously be combined with the fact that the aerosol jet is directed onto a wall of the aerosol chamber, which thus forms a second impact body of a second filter stage, in which large drops remaining in the aerosol jet are separated from the aerosol. At the same time, the aerosol jet impinging on the wall leads to a slow flow of aerosol along the wall and thus also to thorough mixing of the aerosol chamber. Additionally or alternatively the aerosol jet can also be directed through the jet deflecting section in the direction of at least one corner of the aerosol chamber.

In particular, the aerosol chamber can be configured as a pressure container in which the aerosol is kept under pressure above the external environment, so that a constant supply of aerosol consumers with the aerosol is ensured.

Due to the arrangement of the baffle body around which the aerosol jet flows, it is possible, according to a further advantageous embodiment, to arrange the baffle body so that it can move freely in relation to the aerosol outlet in the direction transverse to the aerosol jet direction. On account of the embodiment according to the invention, the aerosol jet can be used as a restoring element which, when the impact body is deflected from its rest position, preferably a central jet, generates a restoring force and automatically centers the impact body. As a result, an optimal position of the aerosol generator can always be achieved for aerosol generation. In addition, the slight movements of the impact body transversely to the aerosol jet result in an unsteadiness of the flow in the aerosol chamber, which likewise leads to better mixing of the aerosol chamber and an improvement in the aerosol quantity.

In a further advantageous embodiment, the impact body can be held by spring elements which generate a restoring force when the impact body is deflected from its rest position. The restoring force can be directed both in the beam direction, but preferably transversely to the beam direction. In an advantageous development, the spring elements can be designed as rod springs which extend in the aerosol jet direction and hold the impact body against a housing of the mixing chamber and / or the pressure vessel.

Instead of or in addition to the spring elements, an automatic adjustment device can also be provided, in which the current position of the impact body is monitored transversely and along the aerosol jet by means of a sensor and is compared with a desired position. If the position detected by the sensor deviates from the desired position, an adjusting device is actuated by which the impact body is moved in such a way that this deviation is eliminated or reduced. The adjusting device can have a drive element in the form of a motor, which has a thread and / or transmission moves a holding element, for example a fixed rod, to which the impact body is attached.

The invention is explained below by way of example using exemplary embodiments with reference to the drawings.

Show it:

Figure 1 is a perspective and schematic representation of an apparatus for aerosol generation.

Figure 2 is a schematic representation of a first embodiment of an impact body according to the invention.

3 shows a schematic illustration of a second exemplary embodiment of an impact body according to the invention;

4 shows a schematic illustration of a third exemplary embodiment of an impact body according to the invention;

5 shows a plan view along arrow V of the impact body of FIG. 4;

Fig. 6. is a schematic representation of a fourth embodiment of an impact body according to the invention.

First, the structure of a device 1 for aerosol generation will be described with reference to FIG. 1. The device can be functionally divided into an aerosol generator 2, in which aerosol is generated, and a control device 3, under whose control the aerosol generator 2 generates the aerosol.

In the device 1 shown in FIG. 1, the aerosol is schematically represented by points 4. The aerosol 4 is directed from the device 1 to aerosol consumers 5, the device 1 in the embodiment shown in FIG. 1 being used as a cooling-lubricating device and as an aerosol consumer 5 cutting tools. In particular, in the embodiment of FIG. 1, drills 6 are used as aerosol consumers 5, which are attached to machine tool spindles 7. Other types of aerosol consumers 5 include, for example, spray heads for, for example, paints or adhesives. The aerosol consumers 5 themselves are not part of the device 1 for aerosol generation.

The aerosol generator 2 has a liquid container 8 which contains a reservoir 9 of the liquid forming the aerosol. Depending on the application, the liquid can be a dye, varnish, an adhesive or a cooling lubricant or a lubricant, such as an oil or an oil emulsion. The liquid is dissolved in the aerosol 4 as a sol in the form of suspended particles, the suspended particles being in the form of droplets or particles with a diameter of not more than 100 μm.

The container 8 is closed in a pressure-tight manner by a cover 10 and is designed as a pressure container in which there is a different pressure, preferably an overpressure, from the environment of the aerosol generator 2.

The space 11 above the liquid supply 9 in the container 8 contains the aerosol 4, which is generated by mixing a gas volume flow, shown schematically by the arrow 12, and a liquid volume flow, shown schematically by the arrow 13, in a mixing chamber (no reference number) of a nebulizer 14 becomes. The space 11 forms an aerosol chamber, which represents a temporary store for the aerosol 4, so that a sufficient supply of aerosol is available for delivery to the aerosol consumers 5.

Inert gases, for example noble gases, or gas mixtures such as air, in particular compressed air, can be used as gases.

The gas volume flow 12 is conducted under pressure through a gas line 15 via a metering device 16 and a further gas line 17 to the nebulization device 14.

A negative pressure is generated by the gas flow in the nebulizer 14, through which liquid from the liquid supply 9 via a liquid line 18, a metering device 19 and a further line 20 is sucked into the mixing chamber 14.

In the nebulizer 14, the liquid in the gas stream 12 is dissolved drop by drop and, while still under pressure, is passed in the form of an aerosol jet onto an impact body 21. The impact body 21 can, as shown in FIG. 1, be arranged completely in the aerosol chamber 11. The aerosol jet strikes the impact body 21, so that fine droplets of constant size are generated by the mechanical interaction between the impact body 21 and the aerosol jet. Drops that are too large are deposited on the impact body and drip back into the liquid reservoir 9.

The impact body 21 thus acts as a filter stage through which aerosol particles above a certain size are filtered out.

The aerosol 4 collects in the aerosol chamber 11 and is conducted out of the aerosol generator 2 via an aerosol line 22. The aerosol 4 is conveyed through the aerosol line 22 in particular by the internal pressure prevailing in the container 8. Alternatively, a delivery device such as a pump can also be provided in the aerosol line.

In addition, the aerosol line 22 can have a suction nozzle (not shown) in the area of its inlet opening 22 ', with which aerosol is actively sucked into the aerosol line 22 from the aerosol chamber 11 via compressed air.

From the aerosol line 22, the aerosol volume flow 24 passed through the aerosol line 22 is distributed to branch lines 25, which lead to the aerosol consumers 5. Any number of aerosol consumers 5 can be connected to a device 1 for aerosol generation, as long as the amount of aerosol generated by the device 1 is sufficient to supply the aerosol consumers 5. In the embodiment of FIG. 1, the aerosol flows distributed on the branch line 25 are guided through a line (not shown) in the rotating machine tool spindle 7 to the drills 6 up to the cutting edges or the location of the chip removal. The control device 3 regulates the function of the aerosol generator 2. It comprises an input device 26a and an output device 26b, for example a conventional computer 26 with a screen and keyboard, and data readers for reading data carriers such as CD-ROMs, floppies, removable disks, tapes and the like. Like. Via the input and output device 26a, 26b, a user can interact with the device 1 and set parameters and setpoints important for aerosol generation. Such parameters are, for example, the aerosol volume flow 24 required to supply the aerosol consumers 5, the average droplet size of the aerosol and the fatness of the aerosol, ie the proportion of the liquid phase in the aerosol. Further parameters or status variables that can be entered by the operator via the input / output device are, for example, the aerosol temperature and the substance variables, such as the viscosity, of the starting materials used to generate the aerosol. The mixing process to be set in the atomizing device 14, ie the volume flows fed to the mixing chamber, the speeds of the volume flows and the temperatures of these volume flows, are determined as a function of these substance sizes. The state of the aerosol generator 2 as well as deviations from the desired state and operational malfunctions are displayed to the operating personnel via the input / output device 26b.

The regulation of the aerosol generation itself takes place in a controller 27, which is shown schematically in FIG. 1. The controller 27 can comprise a microprocessor which is designed as part of a conventional computer or as an electronic circuit specially designed for control tasks.

The controller 27 is connected via a first signal path 28 to the metering device 16 for the gas volume flow 12. The controller 27 is connected to the metering device 19 for the liquid volume flow 13 via a second signal path 29. A third signal path 30 connects the controller 27 to an adjusting device 31, via which intervention in the aerosol generation process in the mixing chamber 14 can be made directly. For example, the adjusting device 31 comprises a motor, by means of which the geometry of an atomizing nozzle (not shown) can be changed. Finally, the controller 27 is connected to the aerosol 23 via a fourth signal path 32.

The signal paths 28, 29, 30, 32 can be designed as an electrical signal line, light-conducting fiber or radio transmission paths for unidirectional and / or bidirectional data transmission.

Furthermore, volume flow measuring devices can be provided in the area of the metering devices 16 and 19 and in the aerosol line 22, by means of which the volume flows 12, 13 through the lines 15, 17 and 18, 20 can be set. Such volume flow measuring devices can include impeller amimometers, hot film superheat wire probes, laser or ultrasound Doppler sensors or differential pressure sensors.

Exemplary embodiments for the configuration of the impact body 21 according to the invention are described below. The same reference numerals are used for components whose structure and function are similar in all exemplary embodiments. The different features of the individual exemplary embodiments can be combined with one another as desired.

2 shows a schematic cross section through a nebulizing device 14. The gas volume flow 12 and, separately from it, the liquid volume flow 13 are fed to the nebulization device 14, both of which mix into the aerosol 4 in a mixing chamber 32. Compressed air with a pressure of about 5 bar is supplied as the gas and oil as the liquid.

The mixing chamber ends in an aerosol outlet 33, through which the aerosol 4 generated in the mixing chamber 32 exits in the form of an aerosol jet 34 and strikes the impact body 21, which is arranged at a distance from the aerosol outlet 33 such that the liquid particles impinging on the impact body 21 Aerosols 4 flow along this and drip into the liquid reservoir 9 on the rear side thereof facing away from the aerosol outlet 33. As can be seen in FIG. 2, the diameter Dp of the impact body 21 in the direction transverse to the aerosol jet direction 35 is dimensioned such that the aerosol jet 34 flows completely around the impact body 21.

At the same time, the diameter D _{P of} the impact body is at least 0.2 times the distance b of the plane of the diameter D _P from the aerosol outlet 33 greater than the diameter D _{s of} the aerosol jet 35 at the aerosol jet or, if the aerosol jet is applied to the aerosol outlet, the diameter D _{A of} the aerosol outlet. The maximum diameter D _{P of} the impact body 21 is preferably at least 0.35 times the distance b of the plane of the diameter D _P from the aerosol outlet 33 greater than that of the diameter D _{s of} the aerosol jet 35 at the aerosol jet or diameter D _{A of} the aerosol outlet.

As can be seen in FIG. 2, the impact body 21 is designed as a hemisphere facing the aerosol outlet 33. The surface of the impact body 21 is smooth with a medium to low surface roughness. For easier assembly, the impact body 21 can be exchangeably fastened on a holding plate, which is only shown schematically by the dashed line, so that it is possible to mount different types of impact bodies 21 on the nebulizing device 14 during series production of the device 1.

The impact body 21 is held so as to be displaceable in the direction transverse to the jet direction 35 relative to the aerosol outlet 33.

In particular, spring bars 37, which are transversely elastic and thus allow a deflection of the impact body 21 in the direction of the arrows 38, serve to hold the impact body 21 or the holding plate 36. In the exemplary embodiment in FIG. 2, the spring bars 37 are fastened to the nebulization device 14 and are preferably designed in terms of flow technology so that they do not lead to an interaction with the aerosol jet, for example swirling or a stagnation area, and thus to an enlargement of the aerosol particles.

Instead of the spring bars 37, a positioning device or position control, not shown in FIG. 2, can also be used, by means of which positioning means during operation an optimal position of the impact body in the aerosol jet is maintained for aerosol generation. For this purpose, a position sensor is provided, through which the current position can be detected and passed on in signal form to a control device. In the control device, the detected position is compared with a target position, the target position being dependent on flow parameters of the aerosol jet, such as the speed of the aerosol jet, the gas-liquid ratio or / and the target droplet size. The position control also has an adjustment device controlled by the control device and at least one holding element for the impact body 21, which is movably held by the adjustment device. The adjustment device is operated in such a way that the deviation between the actual, measured position and the target position of the impact body is regulated to zero.

The spring bars 37 form a restoring element which, when deflected along the arrows 38, centers the impact body 21 back into its original position. The spring elements 37 support the restoring effect of the aerosol jet 34 which, due to the inventive design of the impact body 21, leads to an independent centering of the impact body 21 without complex holding means. Such an automatic resetting is also possible without the additional force of the spring bars solely through the aerosol jet 34.

A trouble-free and robust generation of the restoring force generated by the aerosol jet 34, acting on the deflected impact body 21, is made possible in particular by the configuration of the impact body 21 as a sphere or hemisphere.

Next, a second exemplary embodiment of a device according to the invention will be described with reference to FIG. 3.

For the sake of simplicity, only the differences from the exemplary embodiment in FIG. 2 will be discussed in the description of the exemplary embodiment in FIG. 3.

In the exemplary embodiment in FIG. 3, the impact body 21 is designed as a ball, in which the distance b of the center M from the aerosol outlet 33 is at least 0.1 to 0.3 times the diameter of the aerosol jet 34 at the aerosol outlet 33. Representing the diameter D _{s of} the aerosol jet 34, the Diameter D _{A of} the aerosol outlet 33 can be used when the aerosol jet rests on the wall of the aerosol outlet, so that the diameter does not differ greatly from one another.

The impact body 21 of the embodiment of FIG. 3 is attached to the container 8 via a spring rod 37. The spring bar 37 runs on the side of the impact body 21 facing away from the aerosol outlet 33 along the jet axis of the aerosol jet 34. The spring bar 37 supports the impact body 21 so that it can move in the direction transverse to the jet direction 35. In a further development, the spring bar 37 can also have elasticity in the jet direction 35, so that the impact body 21 can react to pressure fluctuations in the aerosol jet by moving in the jet direction 35. This leads to an even more even aerosol quality. In addition, the movement of the impact body 21 of the aerosol jet 34 creates an unsteady flow in the aerosol chamber 11, which leads to better mixing of the aerosol chamber 11.

Alternatively or additionally, further spring bars 37 can be provided, which are shown in FIG. 3 with dashed lines. The spring bars can extend transversely to the beam direction 35, so that only a displaceability of the impact body 21 in the beam direction 35 is possible.

Finally, in FIG. 3 the nebulization device 17 is configured in two stages, which leads to a particularly fine aerosol in the aerosol stream 34. In the two-stage nebulization device 14, a first aerosol is generated in a first mixing chamber 32a from a first gas volume flow 12a and a first liquid flow 13a, into which a second gas volume flow 12b is then introduced. The already generated first aerosol is then mixed with a second liquid volume flow 13b in a second aerosol chamber 32b.

In the embodiment of FIG. 3, the front portion of the impact body 21 is still arranged within the core jet of the aerosol jet, the length of which is approximately 20 mm at a Reynolds number Re = (v D) / v of approximately 3000. The Reynolds number is formed from the diameter of the aerosol jet at the aerosol outlet, the exit velocity at this point and the kinematic viscosity of the Ae rosol gas. In the operation of the aerosol generator of FIG. 3, Reynolds numbers between 4500 and 15000 can be realized.

4 schematically shows a third exemplary embodiment of an impact body 21 according to the invention. Only the differences between the exemplary embodiment in FIG. 4 and the previous exemplary embodiments are discussed below.

In the embodiment of FIG. 4, the impact body 21 is designed as a sieve surface, the mesh size of the sieve being between 1 and 1.5 times the nominal particle size of the aerosol guided through the aerosol line 22 to the aerosol consumers 5. The arrangement of the sieve 21 in the aerosol jet 34 and its distance b from the aerosol outlet 33 follow the exemplary embodiments in FIGS. 2 and 3. The sieve is thus also automatically centered in the aerosol jet.

FIG. 5 shows a view of the impact body 21 of FIG. 4 along the arrow V pointing in the beam direction 35. As can be seen in FIG. 5, the screen surface 39 is surrounded by a retaining ring 40. The retaining surface 40 stabilizes the screen surface 39 in the aerosol jet.

6 shows a fourth exemplary embodiment of an impact body 27 according to the invention. Only the differences between the exemplary embodiment in FIG. 6 and the previous exemplary embodiments are discussed below.

In the exemplary embodiment in FIG. 6, the impact body 21 has an elliptical, oval or parabolic outer surface facing the aerosol outlet 33, which opens into a beam deflection device 41. The jet deflection device 41 is arranged in an area in which large particles of the aerosol jet 34 are virtually no longer present, since they have already been sieved out by the impact body 21. The combination of the deflection device 41 with the impact body 21 results in a sombrero-like, rotationally symmetrical shape with the centrally projecting impact body. Due to the beam deflection 41, the aerosol jet 34 is diverted on all sides into the aerosol chamber 11, where it leads to a thorough mixing. The aerosol jet 34 can in particular be directed onto a wall 42 of the aerosol chamber 11, against which it impacts and where, after the impact, it leads to a flow 43 along the wall of the aerosol chamber 11. As a result of this configuration, the wall 42 acts as a second impact body, through which large drops are again filtered out of the aerosol jet 34. In addition, the all-round deflection of the aerosol jet leads to vortex-shaped, large-scale circulation flows 44 in the aerosol chamber 11, so that the aerosol is always well mixed and has an approximately uniform distribution of the particle sizes at all points.

In order to allow the aerosol liquid impinging on the impact body 21 to drain, drain openings 45 can be provided at locations where the aerosol liquid would otherwise collect, for example at the transition between the impact body and the deflection device.

Claims

claims 1. Device (1) for generating an aerosol (4), in particular for the cooling and / or lubrication of aerosol consumers (5), such as workpieces, tools and / or machine elements, with a mixing chamber (32) in which a liquid and a gas can be mixed with the aerosol (4), with an aerosol chamber (11) into which the aerosol (4) from the mixing chamber (32) through an aerosol outlet (33) essentially in the form of an aerosol jet (34) and from which Aerosol is directed to an aerosol consumer (5) and with a baffle (21), which is arranged at a distance from the aerosol outlet (33) in the aerosol chamber (11) and onto which the aerosol jet (34) is directed, characterized in that the diameter (D _P ) of the impact body (21) in a plane transverse to the jet direction (35) of the aerosol jet (34) is at least 0.2 times the distance (6) of the plane from the aerosol outlet (33) larger than the diameter of the aerosol jet (34) at the location of the aerosol outlet (33) and is at most so large that the impact body (21) is still surrounded by the aerosol jet (34). 2. Device (1) according to claim 1, characterized in that the diameter (Dp) is at least 0.3 times the distance (b) larger than the diameter of the aerosol jet (D _A ) at the location of the aerosol outlet (33 ). 3. Device (1) according to one of the above claims, characterized in that the distance (b) is at least 0.1 times the diameter of the aerosol jet (D _A ) at the aerosol outlet (33). 4. The device (1) according to claim 3, characterized in that the distance (b) is at least 0.3 times the diameter (D _A ) of the aerosol jet (34) at the aerosol outlet (33). 5. Device (1) according to one of the above claims, characterized in that the impact body (21) has a substantially smooth surface. 6. Device (1) according to one of the above claims, characterized in that the impact body (21) is designed as a hemisphere facing the aerosol outlet (33). 7. Device (1) according to one of the above claims, characterized in that the impact body (21) is designed as a ball. 8. Device (1) according to one of the above claims, characterized in that the impact body (21) is designed as a sieve, the sieve surface of which extends essentially transversely to the beam direction (35). 9. The device (1) according to claim 8, characterized in that the sieve has a mesh size (s) which corresponds at least to the average target particle size of the aerosol consumer (5) directed aerosol (4). 10. The device (1) according to claim 8 or 9, characterized in that the mesh size (s) of the sieve corresponds at most to 1.5 times the average target particle size. 11. The device (1) according to one of the above claims, characterized in that a beam deflection device (41) is provided on the impact body (21), through which the aerosol jet (34) is deflected, so that the aerosol chamber (11) by the aerosol jet ( 34) is mixed. 12. The device (1) according to claim 11, characterized in that the beam deflection device (41) is formed in one piece from the impact body (21). 13. The device (1) according to claim 11, characterized in that the beam deflection (41) is designed as a separate part. 14. The device (1) according to one of claims 11 to 13, characterized in that the aerosol jet (34) is directed onto a wall (42) of the aerosol chamber (11) and impacts it. 15. The device (1) according to any one of claims 11 to 14, characterized in that the aerosol jet is directed into the corners of the aerosol chamber (11). 16. The device (1) according to any one of the above claims, characterized in that the aerosol chamber (11) is designed as a pressure vessel (8). 17. The device (1) according to any one of the above claims, characterized in that the impact body (21) is arranged in the direction of gravity below the aerosol outlet (33). 18. Device (1) according to one of the above claims, characterized in that the impact body (21) is arranged concentrically to the aerosol outlet (33). 19. Device (1) according to one of the above claims, characterized in that the impact body (21) is held relatively freely displaceable relative to the aerosol outlet (33) in the direction transverse and along the aerosol jet direction during operation. 20. Device (1) according to one of the above claims, characterized in that the impact body (21) relative to the aerosol outlet (33) in the direction along the aerosol jet direction is held in operation substantially freely. 21. The device (1) according to one of the above claims, characterized in that the impact body (21) is held by at least one restoring element (34, 37), which in operation when the impact body (21) is deflected from its rest position into the rest position indicative restoring force generated. 22. The device (1) according to claim 21, characterized in that the restoring element is designed as a spring element. 23. The device (1) according to claim 21 or 22, characterized in that the spring element is designed as a bar spring (37). 24. The device (1) according to claim 23, characterized in that the bar spring (37) is attached to the nebulization device (14). 25. The device (1) according to any one of the above claims, characterized in that the device (1) comprises a position control by which the current position of the impact body (21) in the aerosol jet (34) can be detected and a deviation of the current position from one Desired position can be compensated for by a displacement of the impact body (21).