EP0638354B1 - Totally self-cleaning mixer - Google Patents

Description

The invention relates to a multi-axis mixer or reactor with large free usable volume, which kinematically cleans itself, consisting of two or more parallel counter-rotating axes, on which helically offset, conveying blades are mounted, which by axially extended kneading bars with each other are connected and an enclosing housing and optionally an inlet and an outlet for the mix.

The invention is directed to devices for process engineering treatment of fluids and cohesive bulk materials. The device is completely kinematic self-cleaning and has a large free useful volume.

Among other things, in the production and processing of plastics need highly viscous liquids are treated procedurally. In particular equipment is needed for mixing and evaporation. These must be a good one Mischwirkung and in the case of evaporation also a rapid renewal of the free Surface of the mixer cause.

Product deposits on the walls of such mixers can lead to process impairments to lead. In the deposits become unwanted side reactions favored due to the much longer residence time in the reactor. This leads to contamination of the product. Product deposits on the walls can be avoided by kinematic self-cleaning of the mixer.

An example is the preparation of thermotropic, liquid-crystalline polyesters called. Determining the speed in the final stage of the polycondensation is the Mass transfer of the condensate into the gas phase of the reactor under vacuum. This requires the largest possible mass transfer area and one possible rapid renewal of the same. Due to the pronounced structural viscosity tends the product to wall deposits in non-stirred areas. By the here present longer residence times produce black cracking products which, when they enter the product stream, lead to non-salable goods.

With a view to minimizing the manufacturing and operating costs of a Reactor / mixer is also desired a large free usable volume, i.e. the ratio of Rühzwerkvolumen to housing volume should be as possible be low.

These requirements are met to some extent by the Publication DE 41 26 425 A1 described apparatus.

However, the apparatus described there has two serious weaknesses:

For absorbing bending forces, for example when mixing pasty fluids only the shaft of the rotors. But the wave should be as thin as possible, a big one to obtain free usable volume. This is in the also desired small games (because of the self-cleaning) due to the deflection of the shaft a ratio between length of device and center distance of more than 5 at best 7 barely reachable.

A heating of the blades and gears would be in said mixing device only possible through a complicated leadership of the heating channels, through each toothed foot supply and return line must be performed. This is manufacturing technology difficult to master or associated with high costs.

The object of the invention is to provide an apparatus which is completely kinematically is self-cleaning, has a large free volume, the said Does not have disadvantages and in which preferably a heating / cooling of the stripping easy to integrate.

The object is achieved in that in a mehrwelligen Mixer on each shaft helically offset conveying blades are arranged, which are interconnected by axially extended kneading bars.

daß die Knetbarren eines Rotors so gestaltet sind, daß ihre Flächen bei der durch das Antriebsmittel hervorgerufenen Rotation der Rotoren durch Kanten und/oder Flächen der Knetbarren und der Welle eines anderen Rotors vollständig überstrichen werden sowie an ihren in axialer Richtung des Rotors gesehenen Enden auch durch Flächen und/oder Kanten der Förderschaufeln des anderen Rotors überstrichen werden,

daß die Welle eines Rotors so gestaltet ist, daß ihre Flächen bei der durch das Antriebsmittel hervorgerufenen Rotation der Rotoren durch Kanten und/oder Flächen der Förderschaufeln und der Knetbarren des anderen Rotors überstrichen werden,

daß die Innenwand des Gehäuses so gestaltet ist, daß sie bei der durch das Antriebsmittel hervorgerufenen Rotation der Rotoren durch Kanten und/oder Flächen der Knetbarren und Förderschaufeln vollständig überstrichen wird,

daß die in einem Radialschnitt eines Rotors auftretenden Schnittkanten von Förderschaufeln und Knetbarren alle entweder Kreisbögen um den Rotationsmittelpunkt oder Epizykloidenabschnitte sind,

daß die in einem Radialschnitt eines Rotors auftretenden Schnittkanten von Förderschaufeln und Knetbarren alle konkav sind, wenn sie nach innen zeigen und

daß jede Förderschaufel ausgenommen an den Enden des Mischers auf der in axialer Richtung gesehenen Vorder- und Rückseite mit je einem Knetbarren verbunden ist, wobei der bezüglich der axialen Förderung durch die Förderschaufeln stromaufwärts befindliche Knetbarren mit dem bei der Rotation führenden Ende der Förderschaufel und der andere mit dem bei der Rotation folgenden Ende der Förderschaufel verbunden ist.

The invention is a multiaxial mixer or reactor consisting of two or more parallel counter-rotating shafts on which helically offset conveyor blades are mounted, which are interconnected by axially extended kneading bars (the entirety of interconnected shaft, blades and kneading is hereinafter referred to as Rotor referred.), With a drive means for the opposite rotation of adjacent rotors, an enclosing housing with an inlet and an outlet for the mix and in particular with an additional vent pipe for degassing, characterized in that seen in the axial direction of the front and back each bucket of a rotor is designed to be completely swept by the rotation of the rotors caused by the drive means by the edges and / or surfaces of the buckets of another rotor, with the exception of the faces of Conveying blades, which are swept over by the rotation of the rotors of the housing end wall,

in that the kneading bars of a rotor are designed so that their surfaces are completely swept over by the rotation of the rotors caused by the drive means by edges and / or surfaces of the kneading bars and the shaft of another rotor and also by their ends viewed in the axial direction of the rotor Surfaces and / or edges of the conveying blades of the other rotor are swept over,

that the shaft of a rotor is designed so that its surfaces are swept by the edges of and / or surfaces of the conveying blades and the kneading of the other rotor in the rotation of the rotors caused by the drive means,

that the inner wall of the housing is designed so that it is completely swept by the rotation of the rotors caused by the drive means by edges and / or surfaces of the kneading and conveying blades,

that the cutting edges of conveying blades and kneading bars occurring in a radial section of a rotor are all either circular arcs around the center of rotation or epicycloid sections,

that the cutting edges of conveying blades and kneading bars occurring in a radial section of a rotor are all concave when they point inwards and

that each bucket, except at the ends of the mixer, is connected to a kneading bar on the axially facing front and rear sides, the kneading bar upstream of the conveying blades being axially conveyed by the rotating end of the bucket and the other is connected to the following at the end of rotation of the conveyor blade.

The viewed in the axial direction front and back of each bucket a rotor except at the ends of the mixer are by the Feed vanes of another rotor kinematically completely cleaned.

Each kneading bar of a rotor becomes at its ends seen in the axial direction also by the conveyor blades, otherwise by the kneading bars and the shaft another rotor kinematically completely cleaned.

Each wave of a rotor is through the impeller blades and the kneading of a Other rotor kinematically completely cleaned.

The housing is made on its inner wall by the kneading and conveying blades Kinematic completely cleaned.

The occurring in a radial section of a rotor cutting edges of Conveyor blades and kneading bars are all concave when pointing inward (i.e., if the normal vector on the cut edge is a component to Having rotational axis).

Each bucket is except at the ends of the mixer on the in axial direction seen front and back, each with a kneading connected with respect to the axial conveyance through the conveyor blades upstream Knetbarren with the leading end of the rotation of the Bucket and the other with the end of the rotation following Conveying blade is connected.

In this mixer, seen in the axial direction of the front and Rear of each blade of a rotor (except at the ends of the mixer) through the impeller blades of the adjacent rotors, the kneading bars a rotor at their (seen in the axial direction) ends also by the Conveyor blades, otherwise by the kneading bars and the shaft of the adjacent Rotors, the waves through the blades and the kneading of each adjacent rotor and the housing by kneading and conveying blades Kinematic completely cleaned.

Under kinematic cleaning, the smallest possible approach of the moving Parts of the mixer understood, taking into account the manufacturing tolerance can be achieved during mixing, so that the parts without Blocking can slip past each other.

As described overall, a complete kinematic self-cleaning all surfaces of the mixing chamber can be achieved.

Each bucket, with the exception of the bucket at the ends of the Mischers, is connected on its front and back with a kneading bar. Here, with respect to the axial conveyance through the conveyor blades upstream Knetbarren with the leading end of the rotation of the Bucket and the other with the end of the rotation following Conveying bucket connected. Each kneading bar is (except at the ends of the Mischers) connected with two conveyor blades. This arises over the entire mixer length reaching consequences of connected by kneading bars Conveying blades.

These consequences of impeller blades connected by kneading bars take in essentially the bending forces of the rotor due to deflection.

According to their arrangement on the circumference of the rotor is a maximum Area of inertia and thus achieved a minimum deflection of the waves.

The occurring in a radial section edges of the rotors can be mathematically describe:

und

Dann kann die Bewegung eines Punktes

des Rotors 1 im Koordinatensystem des Rotors 11 beschrieben werden als: x 11 y 11 = cos(ω11 *t)-sin(ω11 *t) sin(ω11 *t)cos(ω11 *t) * cos(ω1 *t)sin(ω1 *t) -sin(ω1 *t)cos(ω1 *t) * x 1 y 1 + a 0 . Let 1 and 11 be two rotors with the angular velocities ω ₁ and ω ₁₁ and the midpoints

and

Then the movement of a point

of the rotor 1 in the coordinate system of the rotor 11 are described as: x 11 y 11 = cos (ω 11 * t ) -sin (ω 11 * t ) sin (ω 11 * t ) cos (ω 11 * t ) * cos (ω 1 * t ) sin (ω 1 * t ) -sin (ω 1 * t ) cos (ω 1 * t ) * x 1 y 1 + a 0 ,

In a preferred embodiment, the rotors rotate at the same speed. Here applies ω 1 = -ω 11 ,

n

die Gangzahl,

m

den Grad der Rotationssymmetrie,

ϕ

einen Teilwinkel zwischen nächstbenachbarten Knetbarren,

π

die Zahl 3,14159.... (π) und

ψ

den Versatz zwischen Knetbarren auf Vorder- und Rückseite einer Förderschaufel bedeutet.

A goal in the kinematic cleaning is to achieve the smallest possible clearance of the moving parts. This can be achieved if the torsion angle of all rotors over the length is equal in magnitude, so the torques are equal. This is made possible with a preferred embodiment of the invention by equipping the rotors with identical repeating elements. With gleichschneller opposite rotation this leads to the fact that the partial angle between the next adjacent Kneadbarren a rotor determined to: φ = 2π-2 mψ n . in which

n

the number of gears,

m

the degree of rotational symmetry,

φ

a partial angle between next adjacent kneading bars,

π

the number 3.14159 .... (π) and

ψ

means the offset between kneading bars on the front and back of a bucket.

To avoid vibration excitation, a constant over time is also Desired torque. This is in a particularly preferred embodiment achieved in that to equalize the drive torque of the offset between the kneading bars on the front and on the back of a bucket (ψ) no integer multiple of the partial angle between two nearest neighbors Kneading bar (φ) is. The offset between kneading bars on the front and back of a Shovel is the angle about which a kneading bar around the axis of rotation of the connected shaft must be rotated so that its imaginary axial extension exactly in the kneading bar passes.

The partial angle between two kneading bars is the angle around which a kneading bar the axis of rotation of the connected shaft must be rotated so that it with the other kneading bars comes to cover.

ϕ

den Teilwinkel zwischen zwei nächstbenachbarten Knetbarren,

i

eine ganze Zahl ungleich 0 ohne gemeinsamen Teiler mit o,

l_i

den axialen Abstand zwischen zwei durch Knetbarren verbundenen Förderschaufeln,

l_Σ

die Länge des Mischers und

ψ

den Winkelversatz zwischen Knetbarren auf Vorder- und Rückseite einer Förderschaufel bedeutet.

If the mixer length is an integer multiple of the axial distance between two blades connected by kneading bars, the following should apply to the preferred embodiment of the reactor / mixer: ψ = i O φ, o = l Σ l i in which

φ

the partial angle between two adjacent kneading bars,

i

an integer not equal to 0 without a common divisor with o,

_i

the axial distance between two conveying blades connected by kneading bars,

l _Σ

the length of the mixer and

ψ

means the angular offset between kneading bars on the front and back of a bucket.

With systems rotating at different speeds, the demand for the most possible leads constant torsional ratios to the approach that the degree of rotational symmetry inversely proportional to the amount of angular velocity of the waves is.

A complete heating or cooling of the rotors, conveyor blades and Kneading is possible in a preferred embodiment of the invention, if the Heating / cooling medium is passed through a shaft end, each a partial flow of the Medium through the respective first bucket of a sequence of each other connected kneading and conveying blades to the subsequent kneading, the Following kneading bars and conveying blades over the entire rotor length, through the respective last bucket back to the shaft and from there through the Entrance opposite shaft end is performed, wherein a further partial flow of the Heating / cooling medium is guided through a longitudinal bore of the shaft to the To heat or cool the shaft. In contrast to the one in DE 41 26 425 A1 described apparatus no points on where supply and return line of the Heating medium are passed through a Förderschaufelfuß or a tooth root have to. Accordingly, the production is easily manageable.

Fig. 1

zeigt die Darstellung des prinzipiellen Aufbaus eines erfindungsgemäßen Mischers im Schnittbild in Aufsicht (Fig. 1b) Vorder- (Fig.1c) und Seitenansicht (Fig. 1a).

Fig. 2

zeigt die Darstellung eines erfindungsgemäßen Mischers.

Fig. 3

zeigt die Darstellung eines Radialschnittes durch den Mischer nach Fig. 2, wie er auch als Frontfläche des Mischers erscheint.

Fig. 4a und 4b

zeigen die Darstellung der Drehbewegung in einem Radialschnitt entsprechend Fig. 3 in 18 Momentaufnahmen.

Fig. 5

zeigt eine weitere bevorzugte Ausführungsform des erfindungsgemäßen Mischers.

The invention will be explained in more detail by way of example with reference to the accompanying drawings, in which:

Fig. 1

shows the representation of the basic structure of a mixer according to the invention in a sectional view in plan view (Fig. 1b) front (Fig.1c) and side view (Fig. 1a).

Fig. 2

shows the representation of a mixer according to the invention.

Fig. 3

shows the representation of a radial section through the mixer of Fig. 2, as it also appears as the front surface of the mixer.

Fig. 4a and 4b

show the representation of the rotational movement in a radial section corresponding to FIG. 3 in 18 snapshots.

Fig. 5

shows a further preferred embodiment of the mixer according to the invention.

Examples

In Fig. 1, the basic structure of a mixer according to the invention is shown. In a housing 4 there are two shafts 1, 11. These are each a simple spiral following conveyor blades 2, 7, 12, 17 ... connected. The illustration in Fig. 1 is simplified in so far that the edges occurring in a radial section are not epicycloids and the mixer shown is not completely self-cleaning.

Fig. 2 shows the spatial representation of a mixer according to the invention. The housing is only partially shown. On each shaft of a two-fold spiral following conveyor blades 2, 7, 12, 17 ... are arranged. The front and back sides of the conveying blades are not in planes perpendicular to the axes of rotation, as in FIG. 1, but rather the conveying blades are employed in such a way that they increasingly contribute to the axial transport. The conveying blades are connected by the kneading bars 3, 13 ... on each shaft to 7 sequences of alternating kneading bars and conveying blades. The mixer is designed for an equally fast opposite rotation.

The free usable volume is 68.5% of the housing internal volume.

Kante 314 reinigt die Fläche 445-447,

Kante 414 reinigt die Fläche 345-347,

Kante 324 reinigt die Fläche 455-457,

Kante 424 reinigt die Fläche 355-357,

Kante 334 reinigt die Fläche 465-467,

Kante 434 reinigt die Fläche 365-367,

Kante 344 reinigt die Fläche 475-477,

Kante 444 reinigt die Fläche 375-377,

Kante 354 reinigt die Fläche 416-417,

Kante 454 reinigt die Fläche 316-317,

Kante 364 reinigt die Fläche 425-427,

Kante 464 reinigt die Fläche 325-327,

Kante 374 reinigt die Fläche 435-437,

Kante 474 reinigt die Fläche 335-337,

Kante 315 reinigt die Fläche 443-447,

Kante 415 reinigt die Fläche 343-347,

Kante 315 reinigt die Fläche 442-448,

Kante 415 reinigt die Fläche 342-348,

Kante 325 reinigt die Fläche 457-462,

Kante 425 reinigt die Fläche 357-362,

Kante 325 reinigt die Fläche 463-464,

Kante 425 reinigt die Fläche 363-364,

Kante 335 reinigt die Fläche 462-472,

Kante 435 reinigt die Fläche 362-372,

Kante 335 reinigt die Fläche 463-467,

Kante 435 reinigt die Fläche 363-367,

Kante 335 reinigt die Fläche 473-474,

Kante 435 reinigt die Fläche 373-374,

Kante 345 reinigt die Fläche 414-472,

Kante 445 reinigt die Fläche 314-372,

Kante 345 reinigt die Fläche 473-474,

Kante 445 reinigt die Fläche 373-374,

Kante 355 reinigt die Fläche 422-417,

Kante 455 reinigt die Fläche 322-317,

Kante 355 reinigt die Fläche 423-424,

Kante 455 reinigt die Fläche 323-324,

Kante 365 reinigt die Fläche 423-427,

Kante 465 reinigt die Fläche 323-327,

Kante 365 reinigt die Fläche 432-442,

Kante 465 reinigt die Fläche 332-342,

Kante 365 reinigt die Fläche 433-434,

Kante 465 reinigt die Fläche 333-334,

Kante 375 reinigt die Fläche 432-442,

Kante 475 reinigt die Fläche 332-342,

Kante 375 reinigt die Fläche 433-437,

Kante 475 reinigt die Fläche 333-337,

Kante 375 reinigt die Fläche 443-444,

Kante 475 reinigt die Fläche 343-344,

Kante 316 reinigt die Fläche 451-454,

Kante 416 reinigt die Fläche 351-354,

Kante 317 reinigt die Fläche 454-455,

Kante 417 reinigt die Fläche 354-355,

Kante 327 reinigt die Fläche 464-465,

Kante 427 reinigt die Fläche 364-365,

Kante 337 reinigt die Fläche 474-475,

Kante 437 reinigt die Fläche 374-375,

Kante 347 reinigt die Fläche 414-415,

Kante 447 reinigt die Fläche 314-315,

Kante 357 reinigt die Fläche 424-425,

Kante 457 reinigt die Fläche 324-325,

Kante 367 reinigt die Fläche 434-435,

Kante 467 reinigt die Fläche 334-335,

Kante 377 reinigt die Fläche 444-445,

Kante 477 reinigt die Fläche 344-345,

Fläche 351-316 reinigt die Fläche 448-451,

Fläche 451-416 reinigt die Fläche 348-351.

Fig. 3 shows a radial section corresponding to A in Fig. 1c through the mixer of Fig. 2, as it also shows on the front surface of the mixer in Fig. 2. Thus, wiper 9 of Fig. 2 appears as a line trace 414, 415, 416, 417 and wiper 19 as 314, 315, 316, 317 in Fig. 3. In Figs. 4a and 4b, the same radial section is shown in 18 temporally successive phase images shown during a whole turn of the waves. Here, the cleaning effect becomes clear:

Edge 314 cleans surface 445-447,

Edge 414 cleans the surface 345-347,

Edge 324 cleans surface 455-457,

Edge 424 cleans the surface 355-357,

Edge 334 cleans the surface 465-467,

Edge 434 cleans the surface 365-367,

Edge 344 cleans surface 475-477,

Edge 444 cleans the surface 375-377,

Edge 354 cleans the surface 416-417,

Edge 454 cleans the surface 316-317,

Edge 364 cleans surface 425-427,

Edge 464 cleans the surface 325-327,

Edge 374 cleans surface 435-437,

Edge 474 cleans the surface 335-337,

Edge 315 cleans surface 443-447,

Edge 415 cleans the surface 343-347,

Edge 315 cleans the surface 442-448,

Edge 415 cleans surface 342-348,

Edge 325 cleans the surface 457-462,

Edge 425 cleans the surface 357-362,

Edge 325 cleans the surface 463-464,

Edge 425 cleans the surface 363-364,

Edge 335 cleans the surface 462-472,

Edge 435 cleans the surface 362-372,

Edge 335 cleans the surface 463-467,

Edge 435 cleans the surface 363-367,

Edge 335 cleans the surface 473-474,

Edge 435 cleans the surface 373-374,

Edge 345 cleans the surface 414-472,

Edge 445 cleans the surface 314-372,

Edge 345 cleans the surface 473-474,

Edge 445 cleans the surface 373-374,

Edge 355 cleans the surface 422-417,

Edge 455 cleans the surface 322-317,

Edge 355 cleans the surface 423-424,

Edge 455 cleans the surface 323-324,

Edge 365 cleans the surface 423-427,

Edge 465 cleans the surface 323-327,

Edge 365 cleans surface 432-442,

Edge 465 cleans the surface 332-342,

Edge 365 cleans surface 433-434,

Edge 465 cleans the surface 333-334,

Edge 375 cleans surface 432-442,

Edge 475 cleans the surface 332-342,

Edge 375 cleans surface 433-437,

Edge 475 cleans the surface 333-337,

Edge 375 cleans surface 443-444,

Edge 475 cleans the surface 343-344,

Edge 316 cleans surface 451-454,

Edge 416 cleans surface 351-354,

Edge 317 cleans surface 454-455,

Edge 417 cleans the surface 354-355,

Edge 327 cleans the surface 464-465,

Edge 427 cleans the surface 364-365,

Edge 337 cleans surface 474-475,

Edge 437 cleans the surface 374-375,

Edge 347 cleans surface 414-415,

Edge 447 cleans surface 314-315,

Edge 357 cleans the surface 424-425,

Edge 457 cleans the surface 324-325,

Edge 367 cleans surface 434-435,

Edge 467 cleans the surface 334-335,

Edge 377 cleans the surface 444-445,

Edge 477 cleans the surface 344-345,

Surface 351-316 cleans surface 448-451,

Surface 451-416 cleans surface 348-351.

As can be seen, all circumferential surfaces are cleaned.

Likewise, it is clear that the housing inner walls by the edges 445, 435, 345, 335 ... are cleaned.

The end faces of the housing are e.g. through edges of the terminal blades 9, 19 ... completely cleaned.

A further preferred variant of the mixer according to the invention is shown in FIG. 5 played. This differs from the mixer of FIG. 2 above all in that the conveyor blades 2, 12, 7, 9, 17, 19 ... formed as flat discs are, whose front and back are perpendicular to the axes of rotation 1, 11.

An advantage of this preferred mixer is the simpler construction conditional simpler technical manufacturability of the mixer.

Conveyor blades and kneading bars are prismatic and therefore easily e.g. by milling manufacture.

Claims (8)

1. Mixer or reactor with two or more parallel rotors (1, 2, 3 or 11, 12, 13), with a drive means for rotation of adjacent rotors in opposite directions, consisting of shafts (1, 11), on which are mounted, helically offset, feed blades (2, 12) which are connected to one other by means of axially extended kneading bars (3, 13), and consisting of a surrounding casing (4) with an inlet (5) and an outlet (6) for a material to be mixed, characterised

   in that the front and rear sides, viewed in the axial direction, of each feed blade (2, 12) of a rotor (1, 2, 3 or 11, 12, 13) are so designed that in the event of rotation of the rotors brought about by the drive means they are fully swept by edges and/ or surfaces of the feed blades (12, 2) of another rotor (11, 12, 13 or 1, 2, 3), with the exception of the surfaces of the feed blades (12, 2) that in the event of rotation of the rotors (1, 2, 3 or 11, 12, 13) are swept by the front wall of the casing;

   in that the kneading bars (3, 13) of a rotor (1, 2, 3 or 11, 12, 13) are so designed that in the event of rotation of the rotors brought about by the drive means their surfaces are fully swept by edges and/or surfaces of the kneading bars (13, 3) and of the shaft (11, 1) of another rotor (11, 12, 13 or 1, 2, 3) and are also swept at the ends, viewed in the axial direction of the rotor (1, 2, 3 or 11, 12, 13), by surfaces and/or edges of the feed blades (12, 2) of the other rotor (11, 12, 13 or 1, 2, 3);

   in that the shaft (1, 11) of a rotor (1, 2, 3 or 11, 12, 13) is so designed that in the event of rotation of the rotors brought about by the drive means its surfaces are swept by edges and/or surfaces of the feed blades (12, 2) and of the kneading bars (13, 3) of the other rotor (1, 2, 3 or 11, 12, 13);

   in that the inner wall of the casing (4) is so designed that in the event of rotation of the rotors (1, 2, 3 or 11, 12, 13) brought about by the drive means it is fully swept by edges and/or surfaces of the kneading bars (3, 13) and feed blades (2, 12);

   in that the cutting edges of feed blades (2, 12) and kneading bars (3, 13) arising in a radial section of a rotor (1, 2, 3 or 11, 12, 13) are all either arcs of a circle about the centre of rotation or epicycloid sections;

   in that the cutting edges of feed blades (2, 12) and kneading bars (3, 13) arising in a radial section of a rotor (1, 2, 3 or 11, 12, 13) are all concave when they point inward; and,

   in that each feed blade (2, 12) is connected, except at the ends of the mixer on the front and rear sides, viewed in the axial direction, to a respective kneading bar (3, 13), whereby the kneading bar located upstream in relation to the axial feed by means of the feed blades (2, 12) is connected to that end of the feed blade which leads in the course of rotation and the other kneading bar is connected to that end of the feed blade which trails in the course of rotation.
2. Mixer or reactor according to Claim 1, characterised in that the rotors (1, 2, 3 or 11, 12, 13) are connected to a drive means for rotation of the rotors (1, 2, 3 or 11, 12, 13) at an equal speed in terms of magnitude.
3. Mixer or reactor according to Claims 1 to 2, characterised in that the rotors (1, 2, 3 or 11, 12, 13) exhibit the same number n of series of feed blades (2, 12) distributed over the periphery and connected to one another by means of kneading bars (3, 13), whereby the angular pitch between the respective adjacent kneading bars of a rotor is determined by the equation:  = 2π-2mψn where

   

   is the angular pitch between adjacent kneading bars,

   n

   is the number of threads,

   m

   is the degree of rotational symmetry,

   ψ

   is the offset between kneading bars on the front and rear sides of a feed blade,

   π

   is the number π (3.14159).

4. Mixer or reactor according to Claims 1 to 3, characterised in that, with a view to making the driving torque uniform, the offset (ψ) between the kneading bars (3), (8) on the front and rear sides of a feed blade (7) is not an integer multiple of the angular pitch () between two adjacent kneading bars.
5. Mixer or reactor according to Claims 1 to 4, characterised in that the length of the mixer is an integer multiple o of the axial distance between two feed blades (2) and (7) connected by means of kneading bars (3) and ψ = io  o = lΣll where

   

   is the angular pitch between adjacent kneading bars,

   i

   is an integer not equal to 0 without a common divisor with o,

   l_i

   is the axial distance between two feed blades connected by means of kneading bars,

   ^lΣ

   is the length of the mixer,

   ψ

   is the angular offset between kneading bars on front and rear sides of a feed blade.

6. Mixer or reactor according to Claims 1 to 5, characterised in that its feed blades (2) and kneading bars (3) can be comprehensively heated or cooled.
7. Mixer or reactor according to Claim 6, characterised in that at one shaft end an inlet for a heating or cooling medium is provided, from which a line for heating or cooling medium is guided through the respective first feed blade of a series of feed blades connected by means of kneading bars through the series of feed blades and kneading bars which are connected to one another as far as the end of the rotor and from there is guided out at the end of the shaft opposite the medium inlet and in that another line for heating or cooling medium is guided through a longitudinal bore in the shaft from the inlet to the outlet for the medium.
8. Mixer or reactor according to Claims 1 to 7, characterised in that it comprises an additional vapour port for degassing processes.

Images