FI78402B - ANORDINATION FOR FRAMSTAELLNING AV FLERKOMPONENTSBLANDNINGAR. - Google Patents

Description

78402

Apparatus for preparing mixtures of several ingredients

Technology background

The invention relates to the general use of processing equipment and, more particularly, to an apparatus for preparing mixtures or combinations of several ingredients, preferably dry mixtures. In certain applications, the invention may also be used in the preparation of mixtures containing liquid ingredients.

The invention can be used in the chemical, pharmaceutical and other industries where there is a need to prepare or use powdered dry or wetted compositions.

State of the art

Mixing is one of the most common production process-15 stands. It is used to homogeneously distribute the starting ingredients throughout the volume of the final product.

Numerous mixing devices are known in the art.

Bulk mixers with rotating tanks are mainly used. Depending on the properties of the starting ingredients and the requirements for the final product, the shapes and locations of the vessel may be different with respect to the axis of rotation and may have different elements and devices to facilitate mixing.

Conveyor mixers are also known in the art. In such mixers, the working tank is generally fixed and the active mixing of the material is effected by a rotating or otherwise movable member, most often formed by various vanes, a belt or a screw.

In addition to overflow and tilting, mixing of the powders is performed in such mixers as the bulk mass moves horizontally.

The horizontal movement of the bulk mass is an essential advantage of conveyor mixers over mixers with rotating tanks, which are mainly batch mixers, and for this reason conveyor mixers are used in continuous processes.

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All other types of mixers for powdered materials can, subject to certain conditions, be considered as belonging to the two types of mixers described above.

The serious disadvantages of prior art mixers 5 are high energy consumption, high size and low throughput, as a large mass of material has to be moved at the same time to ensure a high quality distribution of components and only a fraction of the energy is used for proper mixing, the rest of the energy is used. unnecessary vertical movement of large masses of material.

In order to improve the quality of mixing, the current practice comprises a device (cf. U.S. Pat. No. 3,987,967, p. 241-1) in which there is a flow divider of the components between the agitator feed system and the rotor and agitator of the working chamber. a conveyor in which the conveying means are formed by a belt or screw extending under the metering device system to obtain the starting ingredients therefrom and to feed them into the working chamber of the mixer. Thus, premixed material is introduced into the working chamber, and much less energy is used to homogenize it, the size of the mixers is reduced and the throughput is increased.

But even in this case, a large amount of energy is used for non-energy producing work, while the quality requirements and homogeneity of the mixture, which require thorough transverse and longitudinal mixing, result in a larger mixer size and lower throughput.

In addition, separate units of the agitator system (dosing-30 devices, flow divider, and agitator rotor system) in the form of separate components require different connections to feed the material, which causes compaction and environmental contamination problems and leads to large production facilities.

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SUMMARY OF THE INVENTION

The invention is based on the problem of providing a device for the preparation of multi-component mixtures, the structural arrangement of the basic elements of which makes it possible to substantially reduce the energy consumption required for the preparation of the mixture, reduce the size of the mixer and improve its throughput.

This problem is solved by a working member having a vertical housing with channels for loading the ingredients at the top and channels at the bottom for removing the prepared mixtures therefrom, a working member having a drive shaft mounted thereon. coaxially with the housing, for the components of the dosing system 15 and in the housing between the dosing part and the working part of the device, the component flow divider comprises at least one annular trough having a rotation axis equal to the axis of rotation of the working part. the chute.

This construction of a device for preparing a mixture of several components provides that, when the device is in use, a multilayer annular strip is formed in an annular trough comprising alternating layers of starting materials. The layer of each component is in the form of a coil and the entire annular strip is in the form of a plurality of intertwined coils, the number of coils being equal to the number of simultaneous dispensing devices of the dosing system. Note that the thickness of the layer in each helix depends on the power of the given dosing device as well as the speed of the annular chute. The faster the annular chute rotates, the thinner all the coils and the greater the number of turns of the coils 35 in strips of the same height. Therefore, the quality of the mixture is substantially controlled by changing the speed of the annular trough, and, the thinner the layer of ingredients and the higher the number of component coils per unit height of strip in the trough, the better the homogeneity and mixing quality of the ingredients.

An embodiment of the invention comprises an annular trough divided into compartments with downspouts with adjusting flaps for removing material deposited on the bottom of the trough.

This embodiment is preferred for the preparation of dry powder mixtures in which a small amount of a high quality mixture has to be prepared or the mixture has to be prepared in the form of a flow with low throughput.

In a device in which an annular gutter is divided into compartments with lower taps at the bottom, each control flap 15 preferably has a horizontal network surrounded by an alternating current solenoid on which ferromagnetic, kinematically detachable bodies are placed.

This construction of the device makes it possible to improve the quality of powder mixtures of finely divided and small-grained powdered materials. In addition, in order to remove material from the annular trough for guiding the stirrer into the working chamber, the ferromagnetic bodies moving in an intensely varying magnetic field also strongly influence the material in the compartments, thus also improving the mixing of the ingredients during their premixing step.

In the preparation of mixtures containing coarse-grained ingredients, the annular chute preferably comprises a series of conical sup-30 slots coaxially mounted with each other, each of which is connected to a dosing device in the dosing system and has outlet tubes equidistant from the vertical axis of rotation of the drive shaft.

This construction of the device makes it possible to achieve a higher throughput of the mixer and to increase its scope for mixing materials containing coarse-grained ingredients as well as the liquid phase.

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Both of the above-described embodiments of the annular chute in the form of compartments and a series of conical funnels provide good transverse mixing of the material, and the quality of the mixtures 5 prepared in such mixers depends only on the accuracy of the dosing devices.

In order to lower the requirements for the quality of the dosage, while maintaining the high quality of the mixture produced, the annular trough is preferably assembled from parts comprising an outer jacket and an inner jacket forming an adjustable space so that the outer jacket is movable and the inner jacket has a perforation. attached to the housing.

In addition to good cross-mixing, this design of the device provides high quality and easily controlled longitudinal mixing, thus facilitating and speeding up the production of mixtures of the desired class, while reducing the overall cost of the mixing system due to lower accuracy requirements for the dosing system.

The perforation of the inner sheath is preferably made in the form of rectangular, triangular or trapezoidal openings extending along the entire height of the sheath 20.

This embodiment ensures a high throughput of the mixer.

The perforation on the surface of the inner sheath is preferably made along a rising helical line.

This results in high quality longitudinal mixing of the mixture and high throughput of the device.

The device according to the invention and its embodiments are characterized by a simple structure and can be manufactured in any workshop. The device works reliably, is easy to maintain and does not require skilled operating personnel. Energy consumption is minimized and the specific permeability to unit volume is high and virtually any homogeneity of the mixture can be achieved. All embodiments of the mixer operate silently without disturbing the operating personnel. All units can be easily connected to adjacent 6,78402 devices. The vibrations are small and do not interfere with adjacent devices. The device is convenient to transport, assemble and disassemble, as well as easy to repair.

BRIEF DESCRIPTION OF THE DRAWINGS The structural arrangement, special features and other advantages of the invention will become apparent from the following detailed description with reference to the accompanying drawings, which show practical embodiments of the invention, in which Figure 1 schematically shows a sectional view of Figures 2 and 3 show embodiments of an annular trough of the device shown in Figure 1; Fig. 4 is a schematic sectional view of an embodiment of a device for producing a highly poorly flowing bulk material for the preparation of a multi-component mixture; Figures 5 and 6 show a perspective view of embodiments of the annular trough of the device shown in Figure 4; Fig. 7 shows a perspective view of a compartmentalized annular trough with landing taps with adjusting flaps; Fig. 8 is a partially sectioned plan view of the annular trough shown in Fig. 7; Fig. 9 is a general view of a mixer having a compartmentalized annular chute with downcomers with electromagnetic flaps; Fig. 10 schematically shows a section of the mixer shown in Fig. 9; Fig. 11 is a partially sectioned plan view corresponding to Fig. 10; Fig. 12 schematically shows a multi-deck device in which rotating and fixed gutters divided into compartments alternate; 7 78402 Fig. 13 schematically shows a perspective view of a device having an annular trough forming a series of sup-slits; Figures 14 and 15 schematically show sectional views of an embodiment of the device shown in Figure 13; Figures 16 and 17 show perspective views of the relative positions of the coaxial funnels, drive shaft, working part and other parts of the apparatus shown in Figure 13 directly involved in the mixing process; Fig. 18 schematically shows a perspective view of a device in which an annular chute is made in the form of a chute assembled from parts comprising an outer jacket and an inner jacket; Fig. 19 corresponds to Fig. 18 in section; Figures 20, 21, 22, 23 and 24 show some possible embodiments of the fixed inner sheath 15 and its perforation.

Preferred Embodiments of the Invention All embodiments of the apparatus of the invention for explaining the idea of the invention described below form a system comprising the following three basic components: a dosing system 1 (Fig. 1), a component flow divider 2 and a mixer 3.

The dosing system 1 comprises dosing devices 4 which next feed the ingredients called by the letters A ... N in a predetermined amount into a mixture, hereinafter referred to as the letter M. The dosing devices 4 comprise hopper 5 with flaps 6, which may be any known type, as well as outlet pipes (not shown in the drawings) extending into the channels 7 for passing the ingredients to the mixer 3. The feeders 30 of the dosing devices 4 are fed the ingredients from the storage tanks 8 by means of 9.

The component flow divider 2 comprises an annular trough 10 (Figures 1-9) rigidly attached to a vertical drive shaft 11 connected to the rotary drive 12.

35 The lower part of the annular trough 10 has distribution openings 13 (Fig. 2) or 14 (Fig. 3).

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The agitator 3 (Fig. 1) comprises a vertical jacket 15 with a working chamber 16 of the agitator 3, a agitator drive shaft 17 and a working member 18. The drive shaft of the working member 18 may be aligned with the vertical drive shaft of the annular chute 10 of the component flow divider 2. In this case, the rotary drive 12 of the annular chute is also used as the drive member 18 of the mixer 3. If the working member 18 is driven by an independent drive shaft 17, it can be driven by a separate drive 19 10 (Fig. 10).

The annular trough 10 may be divided into compartments 20 (Fig. 7) having lowering taps 21 (Fig. 8) at the bottom provided with adjusting openings 22. An embodiment of the adjusting opening is formed by a disc 23 with openings 24 for covering the lowering taps 21 of the compartments 15 20.

The flaps 6 of the dosing device 4 and the flaps of the compartments 20 of the annular trough 10 may be electromagnetic flaps 25 (Fig. 9) comprising a horizontal net 26 (Figs. 10 and 11) and ferromagnetic kinematically detachable bodies 20 placed on the net. The network 26 with its parts 27 is placed inside the AC electromagnet 28.

A single device may have a plurality of annular troughs that may form a multi-cover arrangement (Figure 12). The movable annular troughs 10 may alternate with the fixed annular troughs 29.

The stirrer 3 can also be made into an electromagnetic device 30 similar to an electromagnetic flap.

As shown in Figures 13-16, the annular trough comprises a series of funnels 31 arranged coaxially with each other and simultaneously rotating about a vertical axis, each corresponding to one dosing device 4 of the dosing system 1, with extensions in the form of inclined tubes 32 at the bottom. 11 center axles at the same distance. Under the tubes 35, there may be means 33 (Fig. 17) for reducing the linear velocity of the flows, comprising a permeable 78402 9 partition wall 34 with vertical or oblique ribs. Below the permeable partition there is an annular flange which can engage the scraper 36. As shown in Figures 18-20, the annular trough is made of a membered assembly comprising an outer sheath 37 movable relative to the housing 15 and an inner sheath 38 mounted to form an adjustable space 39 therebetween. , so that the inner sheath 38 rigidly attached to the housing 15 has a perforation 40 connecting the space between the sheaths 37 and 38 to the interior of the sheath 38. The lower part of the jacket 37 and the jacket 38 terminates in conical funnels 41 and 42 (Fig. 19), respectively, and the space 39 between the jacks 37 and 38 or the funnels 41 and 42 can be adjusted by moving them vertically relative to each other by means of a screw mechanism 43. The central portions of the conical funnels 15 41 and 42 have openings 44 (Figures 21-24), the conical funnel 38 of the inner jacket 38 optionally also being provided with a corrugated surface 45. The perforation 40 may be circumferential, triangular, trapezoidal or otherwise shaped. , openings. The perforations-20 may have wings (Fig. 20) for the transport of the material to be treated.

The device works as follows.

Since the mixture M consists of the ingredients Ά ... Ν (Fig. 10), there is a dosing device 4A ... 4N for each ingredient. The ingredients 25 are loaded into the respective hopper 5 of the dosing devices 4 (Fig. 1), after which the working member 18 of the mixer and the vertical drive shaft 11 are started. If the mixer 3 has a separate drive 19, as shown in Figs. 10, 12 and 15, both drives 12 and 19 are started simultaneously.

: After the annular chute 10 and the working member of the agitator 3 have reached a stable speed, the flaps 6 of the feed nozzles 5 of all the dosing devices 4 open simultaneously to feed the materials 35 to the annular chute 10.

78402 ίο

Due to the rotational movement of the annular trough 10, each component settles into this thin layer shape along the entire annular path and due to the fact that the annular trough 10 bypasses all distribution tubes of all flaps 6 of all dosing devices 4 in one revolution. along coils alternating in a precisely predetermined sequential order.

10 To explain this phenomenon, consider the operation of a device having an annular chute divided into compartments 20, as shown in Figures 7-12.

Assuming that at the time the flaps of the dosing device 4 were opened, the compartment 20 of the dosing device 2 was

15 tea 4A under the distribution tubes and compartment 20 was component B

under the distribution pipe of the dosing device 4B and so on, a strip is formed in the compartment 20 ^ during one revolution of the annular chute 10, which is formed in the order A, B ... N

variable constituents and at the same time form a constituent 2 *. The strip formed in the 20th order in a different order from the following ingredients B, ... N, A. In the same way, the successive order of the ingredients in the compartment 20 becomes "4

order to be C, ... N, A, B, in section 20 d, ... N, A, B, C

OF

In Title 3a 20 N, A, B, C, D ....

For simplicity, in this embodiment, the number of compartments 20 in the annular trough 10 is the same as the number of components in the mixture M, but it is clear that such similarity is not necessary and the component distribution pattern in the annular trough 10 remains similar to that described above.

Therefore, all the components of the mixture M are fed from the annular chute 10 to the working chamber 16 of the mixer 3 (Fig. 1) simultaneously, and since they are distributed and placed substantially throughout the interior of the mixer 3, the mixing process is substantially facilitated and accelerated.

78402 11

It should also be noted that the components of the mixture falling from the annular chute 10 still retain their helical trajectory for some time due to the inertia in the working chamber 16 of the mixer 3, which then also contributes to the mixing.

The adjustable flaps 6 in the compartments 20 of the annular chute 10 make it possible to adjust the supply of ingredients from the annular chute 10 to the working chamber 16 of the mixer 3 and to ensure the timing of operation of all three basic parts 10 of the device.

The control flaps 22 of the compartments 20 are preferably made as electromagnetic flaps 25 comprising a network 26 and ferromagnetic bodies 27 located in the field-15 of the electromagnet 28 supplied by the AC supply lines. Under the influence of an alternating electromagnetic field, the ferromagnetic bodies 27 make a strong movement to open the way for the material towards the net 26, and the mechanical effect of the bodies on the material contributes to the removal of the substance. At the same time, the ferromagnet-20 pieces have a mixing effect on the component strips wound in the compartment 20, so that a premixed mixture enters the working chamber 16 of the mixer 3.

The use of these types of electromagnetic flaps 25 is very convenient for handling dry finely divided granular and powdered materials that tend to form lumps and agglomerates. The splitting operation of the moving ferromagnetic bodies 27 allows as much split material as possible to enter the mixer 3, thus ensuring their best mixing with each other and high quality homogenization.

The device with the electromagnetic flaps 25 may be either the single-headed device shown in Figure 10 or the multi-headed device shown in Figure 12. In the multi-lid embodiment, a plurality of annular troughs 35 are superimposed on different planes, some of which are fixed annular troughs 29 rigidly attached to the jacket 15 of the mixer 3.

78402 12

The movable annular troughs 10 and the fixed troughs 29 are preferably arranged alternately in the direction of material flow.

An electromagnetic device 30 similar to the electromagnetic flaps 30 of the compartments of the annular chute 10 can also be used as the main stirrer 3.

The advantage of this device is based on the fact that the materials can be fed either continuously or intermittently and that the quality of the mixing is greatly improved due to the repeated weight dosing. The main mixer 3 can operate continuously to remove the mixture in the form of a continuous stream.

The mixers described above ensure high-quality and intensive cross-mixing of the ingredients, so that the dosing devices 4 for dispensing the ingredients must be very precise in order to obtain high-quality mixtures.

For coarse-grained ingredients or mixtures containing a liquid phase, the mixer shown in Figures 13-17 is preferably used.

In this mixer, an annular chute 10 is made into coaxial hoppers 31 rotatable about a vertical axis 11, each of which communicates with its dispensing device 4 and the ends of the discharge tubes 32 of which are spaced from a vertical axis of rotation equal to the central axis of the drive shaft 11.

This construction of the device makes it possible to produce high-quality dry mixtures containing ingredients of different grain sizes in low-power mixers which operate with high permeability, and also to use such devices for preparing moistened mixtures containing liquid ingredients.

The outlets of the tubes 32 are preferably in the same plane. This possibility ensures the continuous access of all the layers 35 to the working chamber 16 of the mixer 3, since in such a case the layers are vertically superimposed.

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The outlet pipes 32 of the hoppers 31 can run obliquely. This capability makes it possible to take advantage of gravity and centrifugal acceleration to remove materials.

The working chamber 16 of the mixer 3 has, on the downstream side of the pipes 32, a means 33 preferably comprising a permeable partition 34 for reducing the velocity of the component flows. This rate-reducing means makes it possible to avoid the separation of the mixture containing components of different specific gravity by the action of centrifugal force and to prevent other undesired phenomena associated with centrifugal forces.

The partition wall passing through the component flow rate reducing means 33 may be made of blocks, as shown in Figures 13 and 14. The vertical or oblique ribs dividing the blocks of the permeable partition 34 into blocks help to reduce the tangential component of the centrifugal acceleration.

Below the partition wall 34 passing through the component flow rate reducing means 33, there is preferably a continuous annular flange 35 associated with the scraper 36 movable relative to the flange 35, as shown in Figures 13 and 17. This possibility improves the conditions for long-term mixing of the mixture.

The possibilities of other structural embodiments of the hoppers 31 do not end with the embodiments 25 described above, each of the hoppers can be assembled from parts comprising a movable part and a fixed part and may be provided with a special scraper to facilitate material flow towards the tubes 32. These elements and accessories are not shown in the drawings.

In this apparatus, the metered substance portions of the mixture from each dosing device 4 are fed directly to their respective hoppers 31 and through pipes 32 to a block-assembled septum 34 passing through their ends to lose their horizontal velocity components and deposit into strips 35 in an annular chute 35. into the working chamber 16 of the mixer 3.

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To ensure the functionality of the device, it is necessary that the rate of removal of ingredients from the hoppers 31 through the tubes 32 is higher than the rate of entry of ingredients to the hoppers 31 from the dosing device 4. This condition prevents material 5 from crosslinking into the hoppers 31.

As with the device with a compartmentalized annular trough, this device involves intensive mixing of the ingredients, so that the dosing devices feeding the ingredients to the hoppers 4 must be very accurate and ensure a uniform and continuous supply of ingredients to the hoppers 31.

The dosing device 4 shown in Figures 18 and 19 is subject to much lower accuracy requirements.

This device has an annular trough 10 assembled from 15 parts and comprises an outer jacket 37 and an inner jacket 38 forming an adjustable space therebetween so that the outer jacket 37 is movable and mounted on the drive shaft 11, and the inner jacket 38 is rigidly attached to a fixed housing 15 and provided with a peripheral hole. 40. The lower end of each jacket terminates in tapered conical funnels 41, 42 which form a space 39 therebetween which can be adjusted by moving the inner jacket 38 and the outer jacket 37 relative to each other, for example by means of a screw mechanism 43. To improve longitudinal mixing, the conical funnel 41 of the outer jacket 37 is preferably made less inclined and provided with a smaller center hole 44 (Fig. 21) than the conical funnel 42 of the inner jacket, and the space 39 between the hoppers 1 and 42 should pass only a portion of the mixture through all dispensers. 4 with the lowest total power.

In order to ensure the functionality of the device, the total area of all the perforations 40 of the inner jacket 38 and the space between the hoppers 41 and 42 should guarantee the passage of all material fed to the ring-gutter at the maximum power of the dosing devices 4 used in the dosing system (Figure 1).

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To improve the transverse mixing of the mixture, the surface of the hopper 42 of the inner jacket 38 may be corrugated by radial, e.g. triangular, corrugations 45, as shown in Figures 21, 22 and 23.

To improve the conditions for homogenization of the mixture and its longitudinal mixing, round, triangular, rectangular, rectangular or other openings are made in the surface of the inner hopper 42 extending either over the entire surface of the inner jacket 38 or only to certain portions thereof.

The quality of the longitudinal mixing is improved by making perforations in the surface of the inner jacket along a rising helical line, for example as shown in Figures 22 and 24.

The leading edges of the perforations preferably have either rectangular or triangular wings 46 (Fig. 20) extending to all or part of the opening to facilitate the flow of material into the interior of the inner sheath 38.

Using this embodiment, the dosing devices 4 of the dosing system are first adjusted to a certain output power to prepare a predetermined mixture composition, the respective hopper 20 are filled with the mixture ingredients for each dosing device and more specifically, its movable outer jacket 37. its components flow in thin layers down along the surface of the conical outer jacket 37 towards its conical funnel 41 and space 39. Since not all material can flow through the space 39, the material begins to accumulate as a multilayer strip in the annular chute 10. in the space between the jacket 37 and the fixed jacket 38.

When the height of the multilayer strip in the space between the movable jacket 37 and the fixed jacket 38 reaches the height of the first opening of the perforation of the inner jacket 38, part of the material begins to flow through the perforation 40 and is forced into the conical funnels 41 and 42. from the material passing through the space 39, into the working chamber 16 of the mixer 3, where it is acted upon by the working member 18. However, since the space 39 between the conical cones 41 and 42 and the area of the first opening 40 allow only a portion of the material fed to the annular chute 10 to pass through, its accumulation in the space between the image shell 37 and the fixed shell 38 continues, and the material flows above through the perforations 40, and so on until the total amount of material removed from the annular chute 10 is equal to the total amount of ingredients fed from the dosing devices 4.

Therefore, batches of material are fed to the working part 18 of the mixer 3 simultaneously from different layers of multilayer strip formed of material fed to the annular chute 10 at different times, whereby the longitudinal mixing of the components of the mixture is improved. It is the quality of the long-term mixing that determines the choice of the shape of the perforations 40, which should be performed depending on the desired penetration power, the grain size of the mixture and the physical and mechanical properties of the individual components and the overall mixture.

At the same time, the cross-mixing is affected by the same factors 20 discussed with reference to other embodiments, i.e. the speed of the annular chute 10, the accuracy of the dosing devices 4 and the like and the shape of the guide vanes 46 and 42 of the conical hoppers 41 and 42.

25 Industrial applicability

The device according to the invention ensures the intensive production of high-quality powdered products at a much lower manufacturing cost, which is due to the simpler operation, adjustment and repair of the equipment.

Claims (7)

17 78402 Apparatus for preparing a mixture of several ingredients, comprising a vertical housing 5 (15) with channels (7) for loading the ingredients at the top and channels for removing the prepared mixtures therefrom at the bottom, a working member (18) having a drive shaft (17) , mounted in the housing (15) coaxially therewith, for the components 10 of the dosing system (1) and the component flow divider (2) arranged in the housing (15) between the dosing part (1) and the working part (18), characterized in that the component flow divider (2) 2) comprises at least one annular trough (10), the axis of rotation of which is the same as the axis of rotation of the working part (18), the feed channels (7) being arranged directly opposite said annular trough (10). Device according to Claim 1, characterized in that the annular chute (10) is divided into compartments (20) with downcomers (21) with adjusting flaps (22) for removing the material 20 deposited on the lower part of the chute. Device according to claim 2, characterized in that each control flap (22) is a horizontal network (26) surrounded by an alternating current electromagnet (28) on which ferromagnetic, kinematically detachable bodies (27) are arranged. Device according to claim 1, characterized in that the annular trough (10) comprises a series of conical coaxially mounted cones (31), each of which communicates with one of the dosing devices (4) of the dosing system (1) and has outlet pipes (32), the ends of which are equidistant from the vertical axis of rotation of the drive shaft (11). Device according to claim 1, characterized in that the annular trough (10) is assembled from 35 parts comprising an outer jacket (37) and an inner jacket (38) forming an adjustable space (39) between them, so that ie the 7 840 2 outer jacket (37) 37) is movable and the inner jacket (38) with the perforation (40) is attached to the housing (15). Device according to Claim 5, characterized in that the perforations (40) in the inner jacket (38) are made in the form of rectangular, triangular or trapezoidal openings extending along the entire height of the jacket (38). Device according to Claim 5, characterized in that the perforation (40) on the surface of the inner jacket (38) extends along a rising helical line. 78402