DE102015106005A1 - Device for mixing or moving substances - Google Patents

Abstract

The invention relates to a device (1) for mixing or moving substances, having at least one process space (3) in which the substances can be introduced in metered quantities in predetermined amounts, characterized in that the process space comprises at least first and second chambers (7, 8). each comprising at least one rotatable tool therein, wherein the chambers merge into each other and together form a closed shell or peripheral surface.

Description

The invention relates to a device for mixing or moving substances. In particular, the invention relates to a device for mixing sand with binders and / or additives for the production of foundry molds or cores.

Such a mixing device is for example from the DE 29 29 263 A1 known. Such a mixer has an upwardly open, substantially U-shaped mixing chamber, so that the substances to be mixed can be fed well from above. Advantages of this concept are a high mixing capacity and a short mixing time.

A common problem when mixing sand with binders, especially liquid binders, is the blending quality. There is therefore the object to provide a mixing device of the type mentioned, with which the mixing is improved.

This object is achieved by the invention defined in claim 1. Advantageous embodiments can be found in the dependent claims.

According to the invention, a device for mixing or moving substances is provided, having at least one process space in which the substances can be introduced in predetermined amounts, wherein the process space comprises at least first and second chambers, each with at least one tool rotatable therein, wherein the chambers merge into one another and together form a closed shell or peripheral surface.

In particular, apparatus for mixing sand with binders and / or additives for the production of foundry molds or cores is suitable or provided, wherein the process space forms a mixing chamber.

According to the invention, the chambers are open only in the direction of the adjacent chamber, and are otherwise closed towards the outside. If the chambers are arranged next to one another, this means that the mixing chamber is closed in particular upwards.

In an expedient embodiment, the chambers are circular cylindrical.

The present invention is based on the recognition that in the case of a process chamber or a mixing chamber with a closed lateral surface during operation, ie. H. during rotation of waves, where the tools can be provided and provided with mixing blades, in a transition region between the circular cylindrical chambers, a turbulence zone is formed, in which the sand is mixed particularly well with the binder and / or additives. In particular, it has been found that the closed ceiling of the mixing chamber contributes to the substances to be mixed are conducted into the fluidization zone. As a result, improved mixing quality is achieved. The better mixing results in less formation of lumps or deposits within the mixing chamber.

In one embodiment of the invention, the mixing chamber in cross section has the shape of two identical circular segments, which are adjacent to each other on the chords. In other words, the two circles of the circular cylindrical chambers overlap in cross section. The overlap area is traversed by the mixing blades of both shafts, so that a particularly good mixing is achieved there.

Preferably, the center angle of the circle segments is less than 180 °, in particular between 60 ° and 120 °. The overlapping area thus produced has proven to be particularly favorable.

In one embodiment of the invention, the first and second circular cylindrical chambers are arranged horizontally. A mixer of this type is characterized by a simple and low-maintenance construction.

Preferably, the mixing chamber has a closable opening arranged in a base area of the first and / or second circular-cylindrical chamber for feeding sand into the mixing chamber. Thus, the lateral surface of the mixing chamber can remain closed during the supply of sand, whereby an improved mixing result is achieved even at this stage.

In one embodiment, in at least one lateral surface, in particular an upper region of the lateral surface of the first and / or second circular cylindrical chamber, a nozzle, in particular a downwardly facing nozzle for supplying liquid binders into the mixing chamber is provided. This embodiment has the advantage that the liquid binder can be sprayed on the sand already in the mixing chamber and can be better mixed with it.

In addition, in a lateral surface of the first and / or second circular cylindrical chamber a closable, in particular downwardly facing opening for discharging the mixture may be arranged from the mixing chamber. Through this opening, the mixture may optionally be passed in rotating mixing blades from the mixing chamber in a container arranged underneath.

Advantageously, the tools are each provided with one or more mixing blades, each mixing blade at its free end an extension, which is formed in particular of plastic, wherein the projections moves upon rotation of the waves along the inner circumferential surface of the first and second circular cylindrical chambers be so that deposits on the inner circumferential surface of the first and second circular cylindrical chambers are removed. Preferably, the extensions on a small distance from the inner circumferential surface of the mixing chamber.

In one embodiment, the tools are each arranged on shafts that protrude into the process space and are rotatable in the opposite direction. By oppositely rotating the mixing blades in the two chambers, a particularly good turbulence in the mixing zone between the chambers is achieved. It has been found to be advantageous if four mixing blades are provided on each tool.

An embodiment of the invention will be described in more detail below with reference to the figures. In a schematic representation:

The 1 a mixing device according to an embodiment of the invention in a perspective view;

the 2 the mixing device off 1 without mixing housing; and

the 3 the mixing device off 1 in cross section.

The 1 to 3 show a mixing device 1 according to an embodiment of the invention. The mixing device 1 is used to mix sand with preferably liquid binders and additional additives such as solids to treat the sand so that it is suitable for the production of foundry molds and, above all, cores in foundries.

The mixing device 1 has a mixing housing 2 with a mixing chamber formed therein 3 on. In the mixing chamber 3 extend into two driven waves 4 , at the axial ends of each four mixing blades 5 . 5 ' are arranged. The waves 4 be about a gearbox 6 driven by a drive, not shown.

In the 1 and 3 you can see that the mixing chamber 3 by two overlapping, overlapping circular-cylindrical chambers 7 and 8th is formed. In other words, the distance between the axes of the waves 4 less than the sum of the radii of the circular cylindrical chambers 7 and 8th , As a result, an overlap area is created, which in mixed operation, both the mixing blades 5 as well as the mixing blades 5 ' run through. The waves are turning 4 in opposite directions, with the mixing blades 5 . 5 ' are arranged such that it is in the overlapping area of the chambers 7 and 8th no collision occurs.

The mixing chamber 3 is closed at the top. This results between the chambers 7 . 8th a mixing zone 9 with particularly good turbulence or mixing of the substances to be mixed.

As in particular in the 3 To see, point the free ends of the mixing blades 5 . 5 ' each a kellartige extension 10 on, which is preferably made of plastic. The extension is opposite the radial extent of the mixing blades 5 . 5 ' tilted in the direction of rotation, with the direction of rotation of the waves 4 through the arrows 11 . 11 ' is shown. In operation, the trowel-like extensions 10 at a small predetermined distance (eg, 1-2 cm) from the inner circumferential surface of the chambers 7 and 8th moved, so that deposits are removed from the lateral surface.

In the transition area between the chambers 7 and 8th is in the rear wall of the mixing chamber facing the gearbox 3 in the upper area a closable opening 12 for feeding sand into the mixing chamber 3 intended. Furthermore, at the top of the chambers 7 . 8th each provided a nozzle for injecting liquid binder. In the bottom of the chambers 7 . 8th each is a closable outlet 13 for discharging the mixture from the mixing chamber 3 intended.

LIST OF REFERENCE NUMBERS

1

mixing device

2

mixed housing

3

mixing chamber

4

waves

5, 5 '

mixing blades

6

transmission

7

first circular cylindrical chamber

8th

second circular cylindrical chamber

9

mixing zone

10

kellike processes

11, 11 '

Direction of rotation of the waves

12

lockable opening

13

jet

14

outlet

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 2929263 A1 [0002]

Claims (12)

Contraption ( 1 ) for mixing or moving substances, with at least one process space ( 3 ), in which the substances can be introduced in metered quantities in predetermined amounts, characterized in that the process space comprises at least first and second chambers ( 7 . 8th ), each comprising at least one rotatable tool therein, wherein the chambers merge into each other and together form a closed shell or peripheral surface. Contraption ( 1 ) according to claim 1, for mixing sand with binders and / or additives for the production of foundry molds or cores, wherein the process space ( 3 ) forms a mixing chamber. Contraption ( 1 ) according to claim 1 or 2, wherein the chambers ( 7 . 8th ) are each circular cylindrical. Contraption ( 1 ) according to one of the preceding claims, wherein the process space ( 3 ) has in cross-section the shape of two identical circle segments which lie against each other at the chords. Contraption ( 1 ) according to claim 4, wherein the center angle of the circle segments is less than 180 °, in particular between 60 ° and 120 °. Contraption ( 1 ) according to any one of the preceding claims, wherein the first and second chambers ( 7 . 8th ) are arranged horizontally. Contraption ( 1 ) according to one of the preceding claims, with at least one in a base area of the first and / or second chamber ( 7 . 8th ) arranged closable opening ( 12 ) for feeding sand into the process room. Contraption ( 1 ) according to one of the preceding claims, with at least one in a lateral surface, in particular an upper region of the lateral surface of the first and / or second chamber ( 7 . 8th ), in particular downwardly pointing nozzle ( 13 ) for supplying liquid binders into the process space ( 3 ). Contraption ( 1 ) according to one of the preceding claims, with at least one in a lateral surface of the first and / or second chamber ( 7 . 8th ) arranged closable, in particular downwardly facing opening ( 14 ), for discharging the mixture from the process space ( 3 ). Contraption ( 1 ) according to one of the preceding claims, wherein the tools are each provided with one or more mixing blades ( 5 . 5 ' ), each mixing blade ( 5 . 5 ' ) at its free end an extension ( 10 ), which is formed in particular from plastic, wherein the projections upon rotation of the waves along the inner circumferential surface of the first and second circular cylindrical chambers ( 7 . 8th ) are moved, so that deposits are removed on the inner circumferential surface of the first and second circular cylindrical chambers. Contraption ( 1 ) according to one of the preceding claims, wherein the tools are in each case connected to shafts ( 4 ) are arranged in the process space ( 3 protrude) and which are rotatable in the opposite direction. Contraption ( 1 ) according to one of the preceding claims, wherein on each tool four mixing blades ( 5 . 5 ' ) are provided.

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