EP0930093A2 - Apparatus for stirring a mixture as well as use of apparatus - Google Patents

Abstract

Stirring apparatus comprises a container (23) for the material to be stirred and a stirrer arranged in the container (23) to rotate about its vertical axis (47). The stirrer at the inner wall of the container (23) has paddles (28) connected to a swivel arm (29) rotating about the axis (47). A tongue (27) is arranged at a distance from the inner wall of the container (23) with the paddles (28) between the tongue and the inner wall of the container.

Description

TECHNICAL AREA

The present invention relates to the field of process engineering. she relates to a device for stirring a material to be stirred, comprising a container to hold the mix and one in the container around a vertical axis rotatably arranged stirring tool, which the material to be stirred during the stirring process transported up the inside wall of the container. Such a stirring device is e.g. as a screw cone mixer or dryer from the prior art Technology known and is from the company Hosokawa Micron B.V., Doetinchem, Holland, available on the market under the brand name Vrieco-Nauta.

STATE OF THE ART

• Mischen und Homogenisieren von Trockenstoffen, Pasten und Slurries;
• Ein- und Aufdüsen von Flüssigkeiten in Trockenstoffe;
• Granulieren und Agglomerieren von Pulvern mit Hilfe eines Bindemittels;
• Reagieren unter Normal-, Ueberdruck oder Vakuum;
• Kristallisieren
• Inertisieren;
• Entlüften oder Belüften;
• Lagern und Austragen von schwerfliessenden Schüttgütern;
• Egalisieren von Farben oder Korngrössen;
• Kühlen; und
• Aufheizen.

A known screw cone mixer 10 of the type mentioned at the outset is shown in a simplified side view (with the container cut open) in FIG. 1. The material to be mixed or stirred (powder, pastes, liquids, etc.) is filled from above through a filler opening (not shown) into a container 11 which tapers conically downwards and has a flange-like mixer base 13 through which the material to be mixed or Mix can be removed after the mixing process. The mixing is carried out by a three-dimensional mixing movement by means of a mixing tool, which comprises a mixing screw 15 rotating about an axis 46, which in turn is guided along a pivot arm 17 rotating about the container axis 45 on the inner wall of the container 11. The direction of rotation of the mixing screw 15 is selected so that the mixing screw transports the mix up the container wall and thus ensures convective random mixing. Compared to the mixing screw 15 conveying upwards, the mix sinks downward due to gravity. Due to the conical shape of the container 11, the flow rate of the mix changes depending on the container diameter. The mix is exposed to a constant change in shape, which leads to the formation of shear surfaces within the mix. The screw cone mixer 10 can be used to advantage

• Mixing and homogenizing dry substances, pastes and slurries;
• Injection and injection of liquids into dry substances;
• Granulating and agglomerating powders with the aid of a binder;
• Reaction under normal, positive pressure or vacuum;
• Crystallize
• Inerting;
• Venting or venting;
• Storage and discharge of poorly flowing bulk goods;
• Equalizing colors or grain sizes;
• Cool; and
• Warm up.

If the container of such a screw cone mixer 10 with heatable, e.g. provided by a heating medium through which the walls result Contact dryer. The material to be dried is transferred from the mixing screw to the heated one Run along the container wall where there is contact with the wall heats up and releases moisture.

The known screw cone mixer 10 shown in FIG. 1, however, has several Disadvantages resulting from its constructive structure: Drive of the swivel arm 17 is a through the lid 14 of the container 11 Shaft 18 guided via a gear unit arranged above the cover 14 19 is driven by a drive motor 20. The shaft 18 is as Hollow shaft executed. Likewise, the swivel arm 17 is hollow. Inside the Shaft 18 and the swivel arm 17 is the drive train for the mixing screw 15 housed for driving a separate drive motor 21 on the gear unit 19 is flanged. The necessary redirection in the drive train from the shaft 18 to the swivel arm 17 and from the swivel arm 17 to the mixing screw 15 (in the reversing gear 16) is usually done via gears, the one Lubricate with oil or grease. Because the mix in most cases (e.g. in the pharmaceutical or food sector under no circumstances the lubricant may be contaminated, are on the seal of the inside Drive train for the mixing screw 15 the highest demands put. This leads to high expenditure in the design and manufacture of the Mixer. Nevertheless, there remains a not negligible residual risk that is not in can be tolerated in all applications.

The use is already an alternative to the lubricated gear transmission an unlubricated toothed belt for the drive train of the mixing screw 15 been proposed. This eliminates the problem of contamination limit. However, this solution affects the power transmission, because the toothed belt does not allow direct power coupling and to compensate of the angle that the axis of rotation 46 of the mixing screw 15 with the axis of rotation 45 of the shaft 18 forms, a universal joint can also be provided got to.

Another disadvantage of the known screw cone mixer 10 is there too see that any one powered by a separate powertrain Mixing screw 15 is used to convey the mix. The inside installed, additional drive train for the mixing screw 15 not only requires an additional drive motor 21, but overall a complex and susceptible mechanics in the gear unit 19, in the shaft 18, in the swivel arm 17 and in the reversing gear 16, which causes high manufacturing costs and one high maintenance and repair costs.

Another disadvantage is that the mixing screw 15 is self-supporting is attached to the swivel arm 17. For mixers with large contents or relatively solid Mix material has high bending forces on the mixing screw 15, which leads to loads of the relatively sensitive drive train and either the Impair the operation of the mixer or, in extreme cases, costly damage being able to lead. It has already been suggested in such use cases the lower end of the mixing screw 15 on the mixer base 13 to support, but such storage does not only hinder the outlet of the mix, but also against the influences of the mix be carefully protected.

Another disadvantage arises directly from the rotating mixing screw 15: The Mixing screw 15 extends in a straight line and with a constant screw diameter along its axis of rotation 46. Since the screw as close as possible to the This has to be done along the inner wall of the container 11 necessarily a shape of the container with a straight wall contour, in particular in the form of a cone. Other container shapes, e.g. at the same Base area and height can enclose more volume than the pure cone are practically not used, which considerably increases the flexibility of the mixing principle restricted.

PRESENTATION OF THE INVENTION

It is therefore an object of the invention to provide a stirring device which At the same time, good mixing and stirring results are much simpler and is to be maintained, contamination of the mixed or agitated material is reliably avoided, is characterized by a low susceptibility to faults, and flexible to the can be adapted to a wide variety of applications.

The object is achieved in a stirring device of the type mentioned solved that the stirring tool along the inner wall of the container Includes blades which are rigid with at least one rotatable about the axis Swivel arm are connected. The essence of the invention is therefore that Rotary movement of the stirring tool around the container axis not only to be used to extend the stirring process over the entire container, but also at the same time by means of the blades the material to be stirred on the inner wall of the container to convey upwards. This eliminates the need for a separate drive train for an independent conveyor, as in the prior art by the Mixing screw is represented. This drives the stirrer significantly simplified and less prone to failure. The only remaining seal, namely the sealing of the shaft leading to the outside, on which the swivel arm is attached is simple and unproblematic. The shovels can be flexible in many different ways and adapted to different Container shapes can be arranged within the container.

A first preferred embodiment of the stirring device according to the invention is characterized in that the stirring tool at least one parallel to Inner wall of the container and with the at least one swivel arm rigidly connected sword, on which the blades laterally and in Longitudinal direction of the sword are arranged one above the other that the least a sword is spaced from the inner wall of the container, and that the blades are arranged between the sword and the inner wall of the container are. The design of the stirring tool as equipped with the blades Sword is particularly simple and stable and can be changed the sword shape can be flexibly adapted to different container geometries. If the sword is oriented parallel to the direction of rotation, it sets the rotary movement in Mixture comparatively little resistance. Number and distance of Blades lying one above the other are preferably selected such that the desired upward movement of the mix on the inside wall of the container results.

For example, the sword can be made from a flat profile made of coated (e.g. enamelled) steel or stainless steel to which the blades, which are also made of steel or stainless steel sheets, welded on or screwed or otherwise attached. But it is just as good it is also conceivable for the sword to be made in one piece together with the laterally formed blades train and manufacture as a forging or casting. Should that Mixed material not only be transported upwards on the container wall, but also it can also generate an additional mixing movement inwards be advantageous if according to a development of the embodiment on the side of the sword facing away from the inner wall of the container Inner blades are arranged. The inner blades also ensure that the sword is not one-sided due to the agitated material acting on the blades Bend is loaded.

A second preferred embodiment of the stirring device according to the invention is characterized by the fact that several swords shoveled the axis is evenly distributed around and with associated swivel arms are rigidly connected, and that the swords on their by the swivel arms opposite ends are interconnected and a rigid cage form. By using two, three, four or more swords will not only the stirring or mixing performance increases, but that formed from the swords The cage (or frame in the case of two swords) is considerably less sensitive against the bending forces exerted by the mix.

According to a further, particularly simple embodiment, the blades are formed as sheets at an angle to the axis. The angle of attack of the Sheet metal scoops are chosen so that the mix depends on the Speed of rotation of the sword or swords in the necessary upward movement is moved without excessively blocking the stirrer.

Because the blades along the inside wall of the container are different the mixing screw of the well-known screw cone mixer over a longer one Line lie against the inner wall of the container, it is advantageous if according to a further embodiment of these blades on their facing the inner wall Edge have an edge contour that matches the contour of the inner wall is. This allows the distance between the entire blade length Minimize the bucket rim and inner wall so that, especially if the Stirring device is used as a dryer with heated container walls, the Contact of the agitated or mixed material with the container wall is particularly long and is intense.

In addition to special training and arrangement of the blades, this can also be done the shovel-carrying sword are specially designed and arranged to to influence the mixing or stirring process in a certain way. Becomes According to a further embodiment, a sword is used which is curved coaxially to the axis, the effective cross section of the Sword in the direction of rotation and thus further reduce the resistance. The resistance, which the mix opposes to the rotation of the stirring tool, can also be reduced if, according to another embodiment, the in Edge of the sword lying in the direction of rotation is designed as a cutting edge.

If according to a further embodiment of the stirring device according to the invention the sword is inclined relative to the direction of rotation, each result Different effects depending on the type of inclination: Is the inclination like this that the material to be stirred is transported outside by the rotating sword is the result of the result between the sword and the container wall Cross-sectional narrowing is a nozzle effect, which is particularly evident when stirring Liquids in a dryer or stirred tank is beneficial; the liquid is accelerated in the nozzle, which reduces the boundary layer and the heat transfer between liquid and (heated or cooled) container wall is increased. The flow breaks off behind the mixing tool and the heat transfer is increased again.

If, on the other hand, the inclination is selected so that the material to be stirred is rotated by the Sword transported inwards results between the sword and Container wall a cross-sectional expansion. As a result, in particular when Stirring powder greatly reduces the risk of the powder jamming become.

The container can be made by the inventive design of the stirring tool flexible in its form. Another preferred embodiment The stirring device according to the invention is therefore characterized in that the container into an overhead cylindrical container part and one thereon downward-tapering container part is divided, and that the Stirring tool or the at least one sword divided into two sections which are adapted to the inner walls of the respective container part. Hereby becomes the same cone shape with the same footprint and height significantly increased container content achieved without the advantages of a conical Outlet must be abandoned.

In a first application according to the invention, the stirring device is used as a mixer used. In a second application according to the invention, the Stirring device used as a contact dryer. In a third according to the invention Application, the stirring device is used as a stirred tank.

Further embodiments result from the dependent claims.

BRIEF EXPLANATION OF THE FIGURES

Fig. 1

einen Schneckenkonusmischer aus dem Stand der Technik in der Seitenansicht;

Fig. 2

ein zu Fig. 1 vergleichbares erstes bevorzugtes Ausführungsbeispiel einer Rührvorrichtung nach der Erfindung mit einfach konischem Behälter und einem einzigen mit Schaufeln besetzten Schwert;

Fig. 3

ein zu Fig. 2 entsprechendes zweites Ausführungsbeispiel mit zwei zu einem Rahmen verbundenen Schwertern;

Fig. 4

ein Schwert mit Schaufeln gemäss Fig. 2 bzw. 3 in der Seitenansicht;

Fig. 5a-d

ausgehend von einer Rührvorrichtung mit einem Schwert gemäss Fig. 2 (Fig. 5(a)) die Anordnung der Schwerter in der Draufsicht von oben bei einem Schwert (Fig. 5(b)), bei zwei Schwertern (Fig. 5(c); und bei drei Schwertern (Fig. 5(d));

Fig. 6

ein weiteres bevorzugtes Ausführungsbeispiel einer Rührvorrichtung nach der Erfindung mit einer aus Zylinder-Oberteil und Konus-Unterteil zusammengesetzten Behälterform;

Fig. 7

ein anderes bevorzugtes Ausführungsbeispiel einer Rührvorrichtung nach der Erfindung mit einer zylindrischen Behälterform und ebenem Behälterboden;

Fig. 8

ein anderes bevorzugtes Ausführungsbeispiel einer Rührvorrichtung nach der Erfindung mit einer zylindrischen Behälterform und gewölbtem Behälterboden;

Fig. 9

eine speziell als Rührkessel ausgebildete Rührvorrichtung nach der Erfindung mit langer Welle, am unteren Ende der Welle befestigten Schwertern und zusätzlichen von oben in den Behälter hineinragenden Stromstörelementen; und

Fig. 10a-h

verschiedene Ausgestaltungen des Schwertes einer erfindungsgemässen Rührvorrichtung (Fig. 10(b)-(h)) im Vergleich zur Mischschnecke des bekannten Schneckenkonusmischers (Fig. 10(a)).

The invention will be explained in more detail below on the basis of exemplary embodiments in connection with the drawing. Show it

Fig. 1

a worm cone mixer from the prior art in side view;

Fig. 2

a comparable to Figure 1 first preferred embodiment of a stirring device according to the invention with a simple conical container and a single blade with blades;

Fig. 3

a corresponding to Figure 2 second embodiment with two swords connected to a frame.

Fig. 4

a sword with blades according to Figures 2 and 3 in side view.

5a-d

starting from a stirring device with a sword according to FIG. 2 (FIG. 5 (a)), the arrangement of the swords in plan view from above with one sword (FIG. 5 (b)), with two swords (FIG. 5 (c)) and with three swords (Fig. 5 (d));

Fig. 6

a further preferred exemplary embodiment of a stirring device according to the invention with a container shape composed of a cylinder top part and a cone bottom part;

Fig. 7

another preferred embodiment of a stirring device according to the invention with a cylindrical container shape and flat container bottom;

Fig. 8

another preferred embodiment of a stirring device according to the invention with a cylindrical container shape and a curved container bottom;

Fig. 9

a stirring device specially designed as a stirring vessel according to the invention with a long shaft, swords fastened to the lower end of the shaft and additional baffle elements protruding from above into the container; and

10a-h

different configurations of the blade of a stirring device according to the invention (FIGS. 10 (b) - (h)) in comparison to the mixing screw of the known screw cone mixer (FIG. 10 (a)).

WAYS OF CARRYING OUT THE INVENTION

FIG. 2 shows a first preferred exemplary embodiment that is comparable to FIG. 1 a stirring device according to the invention in side view with cut Container shown. The stirring device 22 has a comparable to FIG. 1 simply conical container 23, the top through a lid 26 and the bottom through a container bottom 25 is limited. Inside the container 23 (in the interior 24) rotates a plurality of inclined ones arranged one above the other Scoops 28 (Fig. 4) which are attached to a sword 27 and over the Sword 27 rigidly connected to a swivel arm 29 rotatable about axis 47 are. The swivel arm 29 is via a shaft guided through the cover 26 30 and a gear unit 31 arranged above the cover 26 with a Drive motor 32 connected and is driven by the drive motor. The on the sword 27 seated blades 28 are close to the inner wall of the Container 23 guided around in a circle. The inclination of the blades 28 4 is chosen such that when the sword moves 27 in Direction of rotation (arrow in Fig. 4) the material to be stirred from the blades 28 on the inner wall of the container is successively transported upwards and in the central part of the container 23 sinks down again. The sword 27 with the blades 28 replaced functionally, the mixing screw 15 from FIG. 1. The swivel arm 29 can for example be designed as a tube. As a sword 27 is preferred a flat profile (e.g. made of stainless steel) is used, the thickness of which is large enough is grown to the mechanical loads during the stirring process be small enough to avoid unnecessary resistance when moving through to cause the mix.

The use of only one sword 27 according to FIG. 2 results in a turning Unbalance, which has an adverse effect on the bearings. In addition, that is free End of the sword sensitive to bending loads from the agitated material, see above that the gap between the blades 28 and the container inner wall is sufficient must be chosen large in order to grind the blades on the wall avoid. However, a large gap width worsens the contact of the material to be stirred with the container wall, which is particularly disadvantageous for contact dryers. It it is therefore advantageous, according to FIG. 3, at least two equipped with blades 28 Swords 27a and 27b to use, which have associated swivel arms 29a and 29b are attached to the common shaft 30. The two swords 27a, b are arranged opposite one another (FIG. 5 (c)) and preferably joined together at their lower ends. They form a stable one Frame that is comparatively insensitive to bending loads caused by the agitated material and has a significantly reduced imbalance. The gap widths between blades 28 and the inner wall of the container can therefore be significantly smaller here to get voted.

A further stabilization and improvement of the synchronism can be achieved if three (or more) swords 27a, b, c on corresponding swivel arms 29a, b, c can be arranged in a star shape (Fig. 5 (d)). Because with each additional Sword also increases the number of blades 28 and thus the stirring power the mixing time (mixing time, Drying time). The geometry of the sword arrangement for one or two and three swords can be seen in Figs. 5 (b) - (c). If the mix does not filled through the cover 26 from above into the container 23, can instead of Swivel arms 29 and 29a, b, c also one in the center of the circle with the shaft 30 connected circular disc can be used on which the swords 27th and 27a, b, c are attached. The blades 28 are preferred according to FIG. 4 formed as a simple, flat sheet metal parts, which are welded to the sword 27 or screwed on. The blades 28 can also be curved in themselves or be rotated about an axis, as is the case, for example, with turbine blades the case is.

The swords 27 and 27a, b, c can - unlike the mixing screw in the known Screw cone mixer - by bending or folding or by angled Easily connect straight sections to different container shapes be adjusted. Preferred examples of those from the simple cone deviating container shapes are shown in FIGS. 6, 7 and 8. At 6 is the container 23 of the stirring device 22 in an overhead cylindrical container part 33 and one thereon downwards adjoining conical container part 34 divided. The stirring tool accordingly has a sword 27 which is divided into two sections 35 and 36 is divided. The section 35 is on the wall of the cylindrical container part 35 adjusted, i.e. it is vertical. The section 36 is on the conical Adjusted container part 34, i.e. it runs obliquely. The one shown in Fig. 6 The shape of the container has the advantage that the container 23 has the same base area and Height compared to the purely conical container of FIG. 2, an increased capacity having. Assuming that the container parts 33 and 34, respectively take up half of the total height of the container 23, results in opposite the purely conical container by an increase in capacity the factor 2.

In the exemplary embodiments shown in FIGS. 7 and 8, the container 23 the stirring device 22 has a purely cylindrical shape. It is different in both Cases the formation of the container bottom: In FIG. 7 the container bottom is 39 just. In Fig. 8 the container bottom 42 is curved. In both cases the sword is 27 into a vertical section 37 or 40 and a parallel to Container bottom 39 and 42 extending section 38 and 41 divided and with correspondingly adapted blades 28 or 28a and 28b. Of course are other container shapes than that within the scope of the invention Fig. 2, 6, 7 and 8 shown possible. In particular, it is advantageous also in the Examples from FIGS. 6-8 to use several swords with blades, to increase stability and the gap widths between the blades and the container wall to be able to reduce. At this point it should be noted that the drive of the stirring tool can not only be done from above through the lid, such as this is the case in the exemplary embodiments explained here, but just as well also from below through the tank bottom. Especially with the containers 7 or 8, this drive alternative can be used with advantage.

As can easily be seen in FIG. 7, the blades 28 promote the material to be stirred along the tank wall in the vertical direction while the blades 28a the material to be stirred in the horizontal direction over the container bottom 39 of Transport inside out, where it is then used as a supply for the bottom of the Blades 28 acts. Such horizontally operating feed blades can also with other, in particular conical, container geometries (e.g. according to Fig. 2 or 3) favorably influence the wake and thus the overall efficiency increase.

If the stirring device according to the invention is used in particular as a stirrer (stirred tank) for liquids (crystallization, viscous liquids, drying of Liquids until dry) or fluid powder is used Fig. 9 embodiment shown is advantageous. Here too, the container is 23 in divides a cylindrical container part 33 and a conical container part 34. The stirring tool is equipped with swords 27a, b, the shape of the container adapted and each divided into corresponding sections that are related 6 have already been described. The swords 27a, b are in this case attached (welded) with their lower end to a shaft 43, which is passed from above through the cover 26 and through the interior 24 of the container 23 extends almost to the container bottom 25. By the Elimination of the swivel arms makes it possible to use the upper cylindrical part of the container 33 within the circle described by the swords 27a, b strip-shaped, projecting downward from the cover 26 into the container 23 To provide current disturbance elements 44, which undesirably rotate the liquid or the fluid powder with the stirrer or completely prevent it.

The advantage of the inventive, particularly in applications as a dryer Solution with rigid blades compared to the conventional rotating one Mixing screw is a comparison of Figures 10 (a) and 10 (b) in plan view clear from above: The mixing screw 15 according to FIG. 10 (a) affects the screw rotating about the axis 46 with its edge only in a narrow (almost punctiform) area the wall of the container 11 and also transported only there the material to be stirred in contact with the wall upwards. On the sword 27 attached blade 28 as shown in FIG. 10 (b), however, the edge contour over the entire blade width of the contour of the wall of the container 23 is adjusted become. The agitated or mixed material conveyed by the blade 28 is therefore clear longer contact to the (heated) container wall than that of the mixing screw funded good. In addition to that between sword 27 and wall of the container 23 arranged blades 28 can also according to FIG. 10 (c) on the inside of the sword 27 inner blades 48 are provided. The inner blades 48 result in an additional stirring effect and at least partially compensate for the from the blades 28 originating and acting on the sword 27 one-sided Bending forces.

Not only the number, shape and arrangement of the blades determine the Stirring or mixing or drying characteristics of the stirring device. Also the Formation of the sword 27 itself has an influence on the operating behavior. Is the sword 27 formed as a straight flat profile, results from the Width of the sword and the rotating movement an effective cross section, which is larger than the actual cross section (thickness x length) of the sword 27. The effective cross section can be reduced to the actual cross section, if the sword 27 is curved coaxially to the axis of rotation according to FIG. 10 (d). A further influence on the stirring characteristics results when the sword is inclined relative to the direction of rotation (tangent to the turning circle). Is the 10 (e) selected so that the material to be stirred is rotated by the rotating Sword 27 is transported to the outside due to the narrowing of the cross-section between sword 27 and container wall the one mentioned above Nozzle effect, which improves especially when used as a dryer Heat transfer between the material to be stirred and the container wall. Is against 10 (f) selected so that the material to be stirred is by the rotating sword 27 is transported inwards, due to the cross-sectional expansion especially when stirring powdery substances Reduced risk of jamming of the mix.

It is important that the sword 27 points to the direction of travel (direction of rotation) related very small cross section. It can therefore be beneficial 10, if the edge of the sword lying in the direction of rotation according to FIG. 10 (g) 27 is designed as a cutting edge 49. This ensures that the resistance of the (especially powdery) mix does not become too large. The same applies the blades 28, which also have the smallest possible cross-section in the direction of movement should have. The goal is to move the mix upwards promote and thrust as little as possible. By not quite avoiding resistance always results in a promotion of Mix in the direction of rotation of the swords. Should this entrainment in the direction of rotation however, to increase the mixing strengthened and made usable 10, it is advantageous to have a take-along element on the sword 27 according to FIG. 10 (h) 50 e.g. in the form of a longitudinally extending sword 27 welded sheet metal strip. Other forms of Driving elements are of course also conceivable.

The size and performance of the inventive can be in a wide range can be selected and are comparable to the size and performance of the known Screw cone mixer. The well-known screw cone mixer or dryer 1 with cantilevered mixing screw is used with container sizes, the a diameter of the base of about 1.45 m to about 2.60 m and have a height of about 1.70 m to about 3.55 m and depending on the container size have a useful volume of about 450 liters to 4000 liters. Will the mixing screw additionally stored at the lower end, containers are used that a diameter of the base of about 2.10 m to about 4.80 m and one Have a height of about 2.80 m to about 7.00 m and one depending on the container size Have useful contents of about 1700 liters to 32000 liters. Comparable container sizes and useful contents are also in the stirring device according to the invention accessible and provided.

If the known screw cone mixer is based on a mixing screw diameter of 200 mm, a mixing screw speed of 90 rpm and a screw pitch of 15 °, this results in a volumetric delivery rate of approximately 28.6 m ³ / h. In order to achieve a comparable delivery rate of 28.8 m ³ / h in the stirring device according to the invention, a stirring tool can be used in which three swords acc. Fig. 5 (d) are arranged on a rotating circle with a diameter of 1800 mm, which rotate at a speed of 30 rpm around the container axis and are equipped with blades which have a length (≈ spacing of the sword-container inner wall) of 100 mm and one Have an angle of attack of 15 °.

Depending on the application and need, the angle of attack of the blades (delivery angle) be between 1 ° and 45 ° and also over the length of the respective Sword vary. The speed for the swords can be between 5 and 300 Rpm. The number of swords is preferably between 1 and 20, the number of blades between 3 and 100. The blade length can be between 5 and 500 mm, the bucket width between 2 and 500 mm.

The stirring device according to the invention can in principle be used in all methods use where a mix has to be stirred. In particular, can the stirring device in the same way and in the same applications as more robust and inexpensive mixer can be used, as in the known Cone screw mixer is the case. The same applies to use as a dryer, in which the container is equipped with heatable walls in a manner known per se is and in addition suction devices or the like. to the container can be connected. The rigidly fixed and rotating around the container axis Shovels take on the function of the mixing screw. Against Above the mixing screw, they have the main advantage of a greatly simplified one and robust mechanics, in which the risk of contamination of the Mix is practically eliminated.

LIST OF DESIGNATIONS

10th

Screw cone mixer

11

container

12th

Mixing room

13

Mixer floor

14

cover

15

Mixing screw

16

Deflection gear

17th

Swivel arm

18th

Shaft (swivel arm)

19th

Gear unit

20th

Drive motor (swivel shaft)

21

Drive motor (mixing screw)

22

Stirrer

23

container

24th

Interior (container)

25th

Tank bottom

26

cover

27; 27a, b, c

sword

28; 28a, b

shovel

29; 29a, b, c

Swivel arm

30th

wave

31

Gear unit

32

Drive motor

33

Container part (cylindrical)

34

Container part (conical)

35.36

Section (sword 27)

37.38

Section (sword 27)

39

Tank bottom (flat)

40.41

Section (sword 27)

42

Tank bottom (curved)

43

wave

44

Current disturbance element

45

Axis (mixer)

46

Axis (mixing screw)

47

Axis (stirring device 22)

48

Inner blade

49

Cutting edge

50

Driving element

Claims (23)

Device (22) for stirring a material to be stirred, comprising a container (23) for receiving the mix and one in the container (23) around a vertical Axis (47) rotatably arranged stirring tool (27; 27a, b, c; 28; 28a, b; 29; 29a, b, c; 48), which the material to be stirred during the stirring process on the inner wall of the container (23) transported upwards, characterized in that the stirring tool Shovels (28; along the inner wall of the container (23); 28a, b; 48), which is rigid with at least one rotatable about the axis (47) Swivel arm (29; 29a, b, c) are connected. Stirring device according to claim 1, characterized in that the Stirring tool at least one running parallel to the inner wall of the container (23) and rigidly connected to the at least one swivel arm (29; 29a, b, c) Sword (27; 27a, b, c) on which the blades (28; 28a, b; 48) laterally and in the longitudinal direction of the sword (27; 27a, b, c) one above the other are. Stirring device according to claim 2, characterized in that the at least a sword (27; 27a, b, c) spaced from the inner wall of the container (23) and that the blades (28; 28a, b) between the sword (27; 27a, b, c) and the inner wall of the container (23) are arranged. Stirring device according to claim 3, characterized in that on the side of the sword (27) facing away from the inner wall of the container (23) additional inner blades (48) are arranged. Stirring device according to one of claims 2 to 4, characterized in that that several swords (27a, b, c) with blades (28; 28a, b) evenly distributed around the axis (47) and with associated Swivel arms (29a, b, c) are rigidly connected. Stirring device according to claim 5, characterized in that the Swords (27a, b, c) at their ends facing away from the swivel arms (29a, b, c) are interconnected and form a rigid cage. Stirring device according to one of claims 1 to 6, characterized in that that the blades (28; 28a, b; 48) are placed at an angle to the axis (47) Sheets are formed. Stirring device according to claim 7, characterized in that the blades (28; 28a, b) guided along the inner wall of the container (23) the inner wall facing edge have an edge contour that the contour is adapted to the inner wall. Stirring device according to claim 2, characterized in that the at least a sword (27; 27a, b, c) is designed as a flat profile. Stirring device according to claim 9, characterized in that the at least one sword (27; 27a, b, c) is curved coaxially to the axis (47) (Fig. 10 (d)). Stirring device according to claim 9, characterized in that the at least one sword (27; 27a, b, c) is inclined relative to the direction of rotation. Stirring device according to claim 11, characterized in that the Inclination is selected so that the material to be stirred is turned by the rotating sword (27; 27a, b, c) is transported outside (Fig. 10 (e)). Stirring device according to claim 10, characterized in that the Inclination is selected so that the material to be stirred is turned by the rotating sword (27; 27a, b, c) is transported inwards (Fig. 10 (f)). Stirring device according to claim 9, characterized in that the in Edge of rotation of the at least one sword (27; 27a, b, c) as Cutting edge (49) is formed (Fig. 10 (g)). Stirring device according to claim 9, characterized in that on the An additional entrainment element on the inside of the at least one sword (27; 27a, b, c) (50) arranged to take agitated material during the rotary movement is. Stirring device according to one of claims 1 to 15, characterized in that the container (23) is simply conical in shape tapered at the bottom. Stirring device according to one of claims 1 to 15, characterized in that the container (23) in an overhead cylindrical container part (33) and a conical container part (34) adjoining it downwards is divided, and that the stirring tool or the at least one sword (27; 27a, b, c) is divided into two sections (35, 36) which cover the inner walls of the respective container part (33 or 34) are adapted. Stirring device according to one of claims 1 to 15, characterized in that the container (23) is cylindrical, and that the stirring tool or the at least one sword (27; 27a, b, c) in two sections (37, 38 or 40, 41) is divided, one of which is against the inner wall of the container (23) and the other is adapted to the container bottom (39 or 42). Stirring device according to one of claims 1 to 18, characterized in that the walls of the container (23) and / or the stirring tool can be heated are trained. Stirring device according to claim 19, characterized in that in Inside of the mixing tool or at least one sword (27; 27a, b, c) circle described at least one current disturbance element (44) is arranged. Use of the stirring device (22) according to one of claims 1 to 18 as a mixer. Use of the stirring device (22) according to one of claims 1 to 19 as a contact dryer. Use of the stirring device (22) according to one of claims 1 to 20 as a stirred kettle.

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