EP1121309B1 - Device for dosing and/or mixing highly viscous and non-flowable materials - Google Patents

Abstract

A device for dosing and/or mixing highly viscous and non-flowable materials, especially pigment pastes. The device includes a funnel which revolves about its own axis and a twin screw arranged inside the funnel. The twin screw arranged in a horizontal position in the funnel and contacts the interior wall thereof. This arrangement ensures that all moveable parts of the device mutually strip and clean one another.

Description

The present invention relates to a device for dosing and / or for mixing of highly viscous and non-flowable materials, especially pigment pastes.

The device is used in continuous and closed systems, especially for dosing the highly viscous and non-flowable materials in an extruder.

The material can be added in a continuously working and closed system, for example using a Buhler pump SRB-83076, whereby the paste-like mass has to be pressed into the pump from a funnel, since it is only poorly sucked in by the pump itself. This can be done by a slide or an auger. It has been shown that sticky, non-flowing pastes stick the funnel and feed elements (feed screws, slide). The glued paste can only be detached from the elements by stripping. According to the principle of the invention, all parts in contact with the product should strip each other and at the same time press the material into the pump. For pastes that only get a pumpable consistency by shearing, such as pigment press cake, the material should be sheared by the stripping elements.
Some devices for dosing, possibly filling or discharging the goods are known from the prior art.

German publication No. 1 180 321 discloses a silo with a discharge device, which has a rotatable bottom surface with driver strips, so that a considerable Part of the fuel in the silo is turned. As a discharge device becomes a snail that lies directly over the contact surface is arranged, and arranged radially from the center of the bottom to an outside of the silo Delivery line system that conveys material used.

In Austrian Patent No. 217959 is a device for discharge described by masses from silos and the like. In a cylindrical container with a an emptying opening is provided towards the center of the inclined floor. A radial arranged snail circles around the container means and brushes the entire Container bottom. In addition to the circular movement, the screw spiral leads another rotary movement around its own longitudinal axis.

German publication DE 3304026 A1 discloses a silo with a discharge device, which has a screw that moves so that the silo is moved against a feeder. When used as a distribution device the snail is driven in the opposite sense. In contrast, is at the top a conveyor shaft arranged a further screw, which is opposite the Conveyor shaft can be pivoted vertically and rotated in it.

French Patent No. 1572866 describes a metering funnel with a Device for dosing powder material which is difficult to flow. A material grant consisting of a transport screw and a dosing screw on the one hand for loosening up and on the other hand for dosing the powdery material. The loosening of the material takes place through the whole Hopper-extending, upward-conveying transport screw with leaves or blades is provided with the material inside by the transport screw of the funnel is moved a little from the bottom up, but then inside of the funnel falls further down or higher from the leaves / blades, which ultimately leads to a certain loosening of the material. The dosage and further promotion of this loosened material takes place through the down promotional dosing screw, which is not inside the actual funnel, but inside a cylindrical sleeve at the funnel outlet below the actual one Funnel stretches. The axes of the transport screw and the metering screw are inserted into each other and therefore identical and form with a cone surface line the funnel an acute angle. This does with increasing height in the funnel Blades / blades getting bigger with the loosening screw necessary so that at least when turning the transport screw get close to the tapered surface area to in the rotating funnel capture and loosen at least a large part of the entire material.

Soviet Patent No. 173584 describes a device with one Funnel and a screw conveyor lying parallel to the inner wall of the funnel, whereby the funnel can rotate about its axis. This device is used to move abrasive or ceramic masses in powder form. While transporting pasty, sticky masses would stick this snail.

The German disclosure DE 3029684 A1 relates to a mixing and filtration apparatus, in which a thickened suspension by means of a predominantly after twin shaft screw conveying above is constantly moved and circulated. This Double-shaft screw is self-cleaning, but cleaning the inner conical surface of the apparatus by stripping by means of the twin screw not provided. Here is a thorough mixing for emptying the apparatus, Swirling etc. is important, which in the case of the thickened but still flowable Suspension in the apparatus is easily the case. For loosening up or Smoothing the filter cake is suggested, the two worm shafts extendable by flexible, elastic attachments or wings that rotate create an inner surface of the apparatus and loosen the filter cake or smooth out.

The object of the present invention is to maintain a constant dosage of highly viscous and non-flowable materials, e.g. Pigment concentrates of all Type (pigment press cake, offset pastes, offset concentrates, flush pastes), aerosil pastes, Steel engraving colors, all types of putty, gel pastes, gelled binders, etc. to ensure. With the developed device, the above should be Disadvantages (clumping of bricks, possibly bridging) are avoided.

The object of the invention is achieved with the features of claim 1. The invention is based on the above-mentioned funnel, which is used as a metering device is the closest prior art. The task becomes solved that a double screw is arranged inside the funnel, and itself the funnel rotates around its own vertical axis. The snail currently replaces it used slide, possibly wipers, mostly on the inner wall of the funnel are arranged. The snails brush against each other and the funnel wall constantly off. By rotating the funnel, the product from the whole Funnel wall stripped again and again.

The further advantageous embodiments of the invention are with the subclaims protected and arise from these claims themselves or their combinations.

It is advantageous that the distance between the inner wall of the funnel and the Double screw is in the range 0-3 cm.

It is advantageous that the screws of the twin screw run in the same direction or in opposite directions are driven.

It is advantageous that the twin screw in the same direction or in opposite directions to that Funnel is driven.

It is expedient that the conveying capacity of the twin screws is higher than the conveying capacity the pump is.

It is expedient that the rotational frequencies of the screw are in the range of 20-100 rpm and of the funnel are in the range 1-5 / min.

Fig. 1 schematisch in Seitenansicht einen Trichter mit der Doppelschnecke,

Fig. 2 eine Draufsicht des Trichters mit den Drehrichtungen beider beweglichen Teile.

The invention is explained in more detail below with reference to the figures. Show it:

1 schematically in side view a funnel with the twin screw,

Fig. 2 is a plan view of the funnel with the directions of rotation of both moving parts.

The materials arrive e.g. from containers or by means of suitable transport devices, both not visible, into a funnel 2. Promotion of the product downwards in the direction of the product outlet opening 4 takes place on the one hand in proportion small extent, by the rotating funnel 2 itself, on the other hand by the Twin screw 1. The screw has two functions, namely wiping and promoting the product. The stripping of the funnel on the inner wall 6 glued pasty mass is caused by the mutual rotations of the funnel 2 and causes the screws 1a, 1b. These rotations can be coordinated may be regulated. It has been shown that the material rotates in the same direction Operation in Fig. 2 is strongly sheared and within a few minutes entire material contained in the funnel 2 is mixed.

Fig. 2 shows the individual screws 1a, 1b, which are driven in the same direction or in opposite directions. These rotations convey the product downwards in the direction of the product outlet opening 4 in FIG. 1 and at the same time shear it. This arrangement has the effect that all parts of the device, including the funnel wall, wipe off one another and, if necessary, clean themselves. For operation with the pump 5, it is important that the delivery capacity of the twin screw 1 is higher than the delivery capacity of the pump. The product then backs up into funnel 2.
Full-leaf and concave snails are particularly suitable for the present device. The Bühler pump SRB-83076 is also used.

List of characteristics

1

twin screw

1a, 1b

snails

2

funnel

3

casing

4

Product outlet opening

5

pump

6

Inner funnel wall

Claims (8)

1. A device for metering and/or mixing highly viscous and non-free flowing materials, in particular pigment pastes, with a funnel that can rotate around its own axis, and a material conveying means situated in the funnel, which extends into the inner funnel wall, characterized in that the material conveying means is a twin worm (1) comprised of two worms (1a, 1b), extends along the inner funnel wall (6) and into a product outlet opening (4) at the lower end, and is guided under the funnel (2) through a casing (3) up to a pump (5) of the device, wherein the conveying capacity of the twin worm (1) exceeds the conveying capacity of the pump (5), wherein all parts (1a, 1b, 2) coming into contact with the material during operation continuously strip each other, and simultaneously press material into the pump (5).
2. The device according to claim 1, characterized in that the distance between the inner wall (6) of the funnel and the twin worm (1) lies within a 0 to 3 cm range.
3. The device according to one of the preceding claims, characterized in that the worms (1a, 1b) of the twin worm (1) are driven in the same direction.
4. The device according to one of claims 1 to 2, characterized in that the worms (1a, 1b) of the twin worm (1) are driven in opposite directions.
5. The device according to one of the preceding claims, characterized in that the twin worm (1) is driven in the same or opposite directions relative to the funnel (2).
6. The device according to one of the preceding claims, characterized in that the speeds lie in a range of 20 to 100 RPM for the worm, and 1 to 5 RPM for the funnel.
7. An extruder with a device according to one of the preceding claims.
8. A continuously operating and self-contained system with a device according to one of claims 1 to 7.

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