DE102005016362A1 - Mixing unit for pourable materials, comprises an inlet for the pourable material, an outlet for the mixed material, and a mixing unit - Google Patents

Abstract

An arrangement for mixing pourable materials, especially powdered plastics, comprises an inlet for the pourable material, an outlet for the mixed material, and a motor driven mixing unit. The outlet pipe length is less than twice the hydraulic diameter of the pipe. The motor drive (8) is located outside the pipe. The arrangement has an additional supply line for a second powder material component. The mixture is supplied to an extruder, and a mixing module (16) is located between a funnel section (4) and the extruder inlet.

Description

The The invention relates to a device for continuous mixing pourable materials, in particular powdery approaches based on thermoplastic materials such as PVC approaches.

Technical area

at the extrusion powdered Plastic mixtures, in particular based on PVC, are usually so-called dry blends used by mixing the powdered PVC with Additives of the formulation, in particular fillers, stabilizers, Lubricants, etc., are produced in separate mixing plants. As far as colored approaches would be extruded every color change with a high cleaning effort of the entire mixing plant connected, would you already mix in the color in this process step.

It is therefore known, the color additives or other ingredients of the mixture that are changed for a product change have to, metered separately, with a metered addition in the task area the extruder is the easiest way.

A Addition of, for example, the color component is problematic, because with it the mixing and homogenization with the remaining ones Components takes place only in the field of extruder screws, so that concentration fluctuations in the final product are not always avoided can be.

A known possibility to avoid or reduce such concentration fluctuations it is, in a separate process step so-called color concentrates These are granular Premixes of the plastic used, in particular PVC, with highly concentrated color additive. The separate production of such However, color concentrates require an additional work step.

task The present invention is therefore to avoid these disadvantages and to provide a device or method that has a rapid change of an additional component to a pourable main component allowing, while minimizing cleaning work, an optimal mix the components is achieved and a low overall height of the device sufficient. Another concern of the invention is constructive and procedurally simplify the previous solutions.

Presentation of the invention

The Invention solves this object by a device (mixing module) according to claim 1, preferably in conjunction with one or more of the features the claims 2 to 6, or by a device according to claim 8, preferably in Connection with one or more of the features of the following Dependent claims.

The Device for mixing the pourable materials, especially powdery Plastic mixtures, such as mixtures based on PVC, have an initial effect Pipe part with an inlet for feeding the pourable material and an outlet for removal of the mixed material. This pipe part has a with his Rotary axis arranged transversely to the axis of the pipe part, motor driven mixing element on. As "transverse to the axis" are also arranged angles deviating from 90 °, however, an approximately rectangular installation is advantageous.

The Tube part can be circular with its cross section However, rectangular or square cross sections have the Advantage that the mixing element can be made easier. So far in the The following is the diameter of the pipe part is in non-round Cross sections so far the hydraulic or the same cross section meant corresponding diameter.

To a preferred embodiment of Invention is the length of the pipe part smaller than twice the hydraulic diameter of the pipe part. As a result, particularly small devices according to the invention possible, being the mixing quality nevertheless excellent. A particular advantage of this compact It is construction that the device according to the invention also in existing Plants in most cases be easily retrofitted can.

When Mixing organs for the device according to the invention can Various geometries are used, such as spirals, double spirals or others familiar to the person skilled in the art To shape. The geometry of the mixing device used is advantageous dependent on adapted from the demands made on the mixing process, the easy change the mixing organs is of particular advantage.

The at least one further pulverulent component may, according to a first variant of the invention, flow into the inlet for feeding the pourable material or into it together with the pulverulent plastic base mixture be added to the hopper of the overall device. Alternatively, the further powdery component with a separate module which is upstream of the mixing module according to the invention, the plastic base mixture may be added. However, the further powdery component is particularly preferably metered directly into the mixing module itself.

To an advantageous embodiment of the Invention, the mixing element is only one-sided in the pipe part stored, wherein the motor drive arranged outside of the pipe part is. This makes it possible on the opposite side of the motor drive, a supply of the second especially powdery To arrange material component.

It could do this if necessary, two or more additional components are added. The Metering is advantageously carried out by laterally attached to the pipe part openings by means of commercial Dosing, in particular dosing units, the main components of a hopper and having a motor driven screw insert. Such Dosing units are known in principle to the person skilled in the art.

It is particularly advantageous when these metering devices pivot across from the pipe part are arranged so that repairs or cleaning very easy to do can be.

To a preferred embodiment of Invention, the pipe part at the inlet and at the outlet in parallel to each other arranged flanges, so that the entire device according to the invention (Mixing module) easily into existing facilities for extrusion a plastic mixture inserted and can be replaced if necessary.

The inventive mixing module is preferably used in an overall device for extrusion a plastic mixture in which a powdered plastic base mixture via a hopper fed to an extruder The use is characterized in that the Mixing module between the feeding hopper of the extruder and the inlet opening of the Extruder is arranged. Here is the short length of the inventive mixing module especially advantageous.

Especially preferred is the second powdery Component a color component. Here are the benefits of inventive mixing module especially due to the short residence time of the dye batch a cleaning of the plant is either not necessary or very easy to do.

Prefers is the aforementioned mixing module according to the invention between the Feed hopper on the one hand and the inlet opening of the extruder on the other arranged, it being within the scope of the invention, if more Devices or units in the conveying direction of the material are arranged.

The Invention is used in extrusion plants, in particular for Extrusion of colored thermoplastics.

Short description of drawing

The Invention will be described below with reference to some embodiments and the drawings explained in more detail. It show:

1 a cross section through an extrusion plant with combination mixing module (symbolic);

2 a cross section through an extrusion plant with inclined mixing module and separate metering (symbolic);

3 a mixing module in cross section;

4 a mixing module in cross section;

5 a mixing module in cross section;

6 a mixing module in cross section;

7 a cross section through an extrusion plant with mixing module and separate metering, mixer disassembled (symbolic);

Ways to execute the invention

In 1 is an extrusion plant for the production of window profiles for processing a colored PVC approach in cross section symbolically shown. The main components known to the person skilled in the art are the storage container 1 for the undyed PVC dryblend 18 , the stage 2 as a base of the reservoir 1 , the pipe inlet 3 and the hopper 4 and finally the extruder 10 with extruder screw 11 , The PVC dryblend 18 gets out of the reservoir 1 over the pipe inlet 3 in the hopper 4 ,

At the in 1 illustrated embodiment of the invention is a high-dose color batch 19 from the color batch funnel 5 by means of the dosing screw 6 from the side of the combination merge module 7 - referred to as combined mixing module - supplied and in this with the PVC-Dry glare 18 intimately mixed. The dryblend / color batch mixture is then immediately into the inlet port of the extruder 10 conveyed and in the extruder 10 melted, homogenized and processed via a tool not shown to a window profile.

The combi-mixing module 7 from this example has the drive as main components 8th , the housing forming the pipe part 12 and as a double spiral or double spiral mixing element 9 executed on mixing part. Due to the laterally flanged drive 8th On the one hand, and the color batch feeder on the other, the overall height is so low that the combi blender module 7 As a rule, retrofitting can also be retrofitted in an existing extrusion line. The combi-mixing module 7 is between the hopper of the extruder and the inlet opening of the extruder 10 arranged. The mixing module 16 with double helix mixer 9 is - without color batch dosing - in 5 and 6 again shown separately in two sections. The housing 12 has an approximately rectangular cross-section, so that the formation of dead spaces is avoided and optimum mixing is favored.

The entire combi-mixing module 7 according to the embodiment in 1 is with flanges between the fixed hopper and the inlet port of the extruder 10 attached, so that it can be removed laterally for cleaning or maintenance purposes from the plant. The drive 8th and the mixing organ 9 form, in particular from 7 It can be seen, a unit that is laterally through the opening 17 from the mixing module 7 can be pulled out. So is a targeted cleaning z. B. especially easy after a color change. Similarly, the color batch addition ( 5 . 6 ) horizontally pivotable on the combi-mixing module 7 attached so that they can be cleaned by the combi-mixing module 7 can be swung.

In 2 and 7 in each case an alternative embodiment of the invention is shown as a schematic diagram. Here, the addition of two Farbbatche via the color batch funnels 5 . 5a . 5c by means of dosing screws 6 . 6a . 6c in a separate module 15 , above the mixing module 16 is arranged. The mixing module 16 according to 2 is arranged at an angle of 45 ° relative to the otherwise vertical flow direction of the dryblend. At the in 7 variant shown is in the module 15 through the leadership 13 ensure that the two pourable components - dryblend from the feed chute and color batch from the dosing screws 6a . 6c - separated from above the mixing module 16 be supplied.

How out 3 and 4 can be found, z. B. propeller mixing organs 14 be used instead of helical or spiral mixing organs.

1

Reservoir (dryblend)

2

stage

3

pipe supply

4

hopper

5

Color batch hopper

6

dosing screw

7

Combined mixing module

8th

drive

9

Double helix mixing element

10

extruder

11

extruder screw

12

Mixer housing

13

guide

14

Propeller mixing member

15

separate Color metering

16

mixing module

17

opening

18

PVC dry blend

19

color batch

Claims (10)

Device for mixing pourable materials, in particular powdery Plastic mixtures (mixing module) - with an inlet to the Respectively of the pourable material and an outlet for discharging the mixed material having tubular part - and one with its axis Arranged transversely to the axis of the pipe part, motor-driven mixing element. Device according to claim 1, characterized in that that the length of the pipe part is smaller than twice the hydraulic diameter of the pipe part. Device according to Claim 1 or 2, characterized that the mixing element is mounted only on one side. Device according to one of claims 1 to 3, characterized that the motor drive outside the pipe part is arranged. Device according to one of claims 1 to 4, characterized through an additional Feeding at least a second powdered Material component within the pipe part. Apparatus according to claim 5, characterized in that the additional supply of the second material component by a laterally on Pipe part arranged metering device takes place, the inlet is arranged in the pipe part diametrically opposite to the motor drive of the mixing element. Device according to one of claims 1 to 6, characterized that the inlet for feeding of the pourable material and the outlet for removal of the mixed material as mutually parallel flanges are formed. Device for extruding a plastic mixture, when a powdered Plastic base compound together with a second powdery component fed to an extruder characterized by the use of one between the hopper of the extruder and the inlet opening of the extruder arranged mixing module according to one of claims 1 to 7th Device according to claim 8, characterized in that that the second powdery Component is a color component. Apparatus according to claim 8 or 9, characterized that between the feed hopper of the extruder and the inlet port of the Extruder arranged mixing module - A pipe part with an inlet for feeding of the pourable material and an outlet for removal the mixed material, - one arranged with its axis transverse to the axis of the pipe part, motor driven mixing element - and at least one metering device for metering at least one second powdered component having, the metering device being pivotable with respect to Extruder and the hopper arranged unit formed is.