DE102016100153A1 - Mixer and mixing tool - Google Patents

Abstract

The invention relates to a mixing device (1) for mixing mixed material with a container (2) rotatably mounted about a vertical axis (3) for receiving the mixture with an opening (4) and through the opening (4) into the container (2). reaching in and around a rotation axis (9) rotatable mixing tool (7) with at least one mixing coil (12) to transport the mix substantially along a container wall (15) of the container (2) upwards, wherein the axis of rotation (9) of the mixing tool (7) obliquely to the vertical axis (3) of the container (2). The container bottom (11) is cone-shaped and the mixing tool (7) carries a plurality of mixing arms (20), wherein at least one of the mixing arms (20) on the side facing away from the central shaft (13) has a freestanding end.

Description

The invention relates to a mixing device for mixing mixed material, such as dry and / or wetted solids and / or liquids, with a rotatably mounted about a vertical axis container for receiving the mix with an opening and a reaching through the opening into the container and rotatable about an axis of rotation Mixing tool with at least one mixing spiral to transport the mix substantially along a container wall of the container upwards, wherein the axis of rotation of the mixing tool is in operation obliquely to the vertical axis of the container. Furthermore, the invention relates to a mixing tool.

Such a mixer is for example in the DE 29 02 570 C2 described. The mixer has a downwardly tapered container which is closed by a rotatably mounted on the container lid. A rotatably disposed in the container screw is held off-center on the lid and extends obliquely to the central axis and parallel to the side wall of the container in the direction of the container bottom, which is formed as tapering upwards. The problem with this mixer is that, in particular in the bottom area of the container wall, material accumulations can occur and that the mix can not be effectively mixed.

From the DE 707 621 A a device for mixing powdery substances is known, comprising a container for receiving the mixed material and a mixing tool in the form of a mixing screw on a worm shaft. The container has at its lower end an outlet for the mix. By rotating the worm shaft, the mixing screw conveys the mix from the lower end to the upper end of the container. The worm shaft is hollow and provided with nozzles to introduce liquid or plastic substances under pressure into the interior of the vessel.

To guide the worm shaft close to the container wall, this is made in two parts, with the individual parts are coupled via a universal joint. At the bottom of the container, which is just shaped, as well as at the upper end of the worm shaft this is rotatably mounted centrally on the container in each case. At the lower end or part of the screw, this has a stirring or bluff body in the form of an L-shaped arm, which is arranged directly above the bearing of the worm shaft. The disadvantage here is that, especially in the area of storage material accumulation arises that is not mixed effectively. The two-part design of the shaft is difficult, because it makes an additional storage in the lower tank area necessary. In addition, the system is not suitable for mixing devices in which the container is provided not only as a mixing container but also as a transport container that can be removed from the mixing device. For industrial use, such a mixing device is inefficient, because with removal of the mixing container and the agitator is removed.

A similar concept describes the DE 24 25 727 C3 , The mixing device described therein comprises a mixing vessel which widens conically upwards and which rotates about its central axis and which comprises two spiral-shaped stirring members which project into the container obliquely and on opposite sides of the container wall. Centrally at the bottom of the container, a vortex device is provided, which consists of a rotatably mounted in the container bottom hub, which comprises a concentrically provided with a nozzle injection pipe and mixing arms. The container bottom extends from the side wall in the direction of the container center initially obliquely upwards and then goes over into a steeply upwardly extending point on which the hub is rotatably mounted.

The mixing arms are arranged at the upper end of the hub and thus spaced from the container bottom

The object of the present invention is to propose a mixing device which exhibits more efficient mixing properties in the bottom area of the container. Furthermore, the mixing device should have a simpler structure.

This object is solved by features of claim 1.

According to the invention it is provided that the container bottom is conical and that the mixing tool carries at a directed to the container bottom of the container end multiple mixing arms, which are fixed at one end to a central shaft of the mixing tool and which are guided by rotation of the mixing tool along the bottom, said at least one of the mixing arms has a freestanding end on the side facing away from the central shaft side.

The at least one mixing arm is free-standing at the other end, which is opposite to the one end, which is fixed to the central shaft and, for example, not attached to the mixing helix. It extends from the central shaft in the direction of the container wall and ends in a section which in particular does not carry the mixing helix. He is to be distinguished from a holding arm. Retaining arms are provided on the central shaft to keep the mixing coil at a distance from the central shaft. she are attached at one end to the central shaft and at the other end they carry the mixing coil.

The conical bottom is formed so that it tapers upwards or tapers upwards and effectively directs the mixture in the direction of mixing helix or mixing arms. Due to the inclination of the axes of rotation, the mixing arms rotate obliquely to the container axis. When the container is rotated, a mixing arm and a section of the container bottom pass one another or pass each other and then move away from one another again. The additional mixing arms sequentially pass a bottom section and a mixing arm past each other. Deposition or even sticking to the floor are excluded. Ideally, a bottom section and a mixing arm pass very close together, effectively draining the material from the bottom.

The fact that the mixing arms move along the floor past this in rapid succession, this sensitive area is better mixed and material accumulation in the floor area are efficiently avoided. The mix therefore does not have time to settle. The additional mixing arms have a boosting effect in terms of mixing efficiency and act as a kind of booster that enhances the mixing effect before the material is transported up through the helix. The mixing tool preferably terminates at a distance from the ground, so that abrasion is avoided. The mixing tool thus projects only from above into the interior of the container. The mixing arms can be guided at a distance from the bottom along, which may be preferably 3 mm to 20 mm. In contrast to other constructions, the construction of the mixing device is significantly simplified.

The Mischarmkonstruktion differs from the mixing spiral in particular in that the mixing arms do not extend helically around the central shaft. The mixing arms may extend radially outward or towards the container wall from the central shaft of the mixing tool. It is also possible that the mixing arms are offset from the central shaft, so that the extension of the mixing arm or its longitudinal axis spaced from the axis of rotation of the central shaft and this does not intersect.

It has proven to be advantageous if the container is designed so that it tapers conically down to the container bottom. Opposite the container bottom is the opening through which the mix can be introduced and through which the mixing tool is also introduced into the container so that it floats above the floor. The container may be connectable to a drive which rotates the container about its vertical axis. Ideally, the upper end of the conical bottom converges with the vertical axis of the container, which may also be the axis of rotation of the container. In cross section, the container bottom may at least partially have the shape of a triangle.

Preferably, the number of mixing arms is greater than the number of mixing helices. This ensures that the mix is whirled up before it is transported up through the coil. The mixing arms provide turbulence effects between the coils, which further improves the mixing result. In particular, the rapid sequence of the mixing arms, which can cause considerable turbulence, comes into play in comparison with a mixing spiral.

Preferably, the mixing arms converge in a common portion of the central shaft. They can be distributed in a cone-shaped plane corresponding to the cone-shaped plane around the central shaft, so that the mixing arms open obliquely, that is not perpendicular to the rotation shaft in the central shaft.

The section of the central shaft, which carries the mixing arms, can connect directly to the helix or mixing helix. Accordingly, the helix can extend in the axial direction of the mixing shaft up to the section which carries the mixing arms. An advantageous embodiment provides to end the helix in one of the mixing arms. This means that at least one of the mixing arms is also designed as a holding arm.

To realize a mixer bell to easily remove the lid and mixing tool from the container, the mixing tool can be attached to the container lid. Preferably, this carries the drive for the mixing tool. The mixing tool can be mounted on the container lid and / or stored and extend from the direction of the upper container opening in the direction of the container bottom, without being supported on this. Due to the oblique arrangement of the mixing tool, the axis of rotation of the mixing tool moves in the direction of the container opening from the high and medium and / or rotational axis of the container. The mixing tool may be formed as a mixing screw and having one or more helically upwardly extending coils that transport the material from the lower end of the mixing vessel to the upper end of the mixing vessel. Ideally, the helix is designed such that it runs along the inner container wall or inner lateral surface of the container during rotation of the central shaft and thereby transports the mix upwards.

The mixing coil can be formed continuously in the axial direction of the central shaft. But it can also be divided into individual, spaced apart helical segments, similar to an interrupted helical flight.

The proposed mixing device is particularly suitable for mixing powdered, granular, pasty and / or liquid mix and can be used for example in dough production with great efficiency.

A particularly advantageous embodiment of the invention provides that the mixing tool has at least six mixing arms preferably uniformly distributed in the circumferential direction of the central shaft. These can be attached to the central shaft as indicated above and extend in a star-shaped outward direction. In particular, adjacent mixing arms can each have the same angular distance from each other.

The mixing arms can be designed so that a flat bottom of the mixing arms on the ground is long. According to a further embodiment of the invention, the underside of the mixing arms is guided parallel to the conical surface of the container bottom or on a portion of the conical surface of the container bottom.

A further embodiment of the invention provides that the mixing arms have an inclined surface in the direction of rotation intended for operation. The inclined surface may be formed on a front portion of the mixing arms and, upon rotation of the central shaft, form the front or a frontal portion of the mixing arms. In order to generate a kind of planing effect, the mixing arms can have a profiled, in particular sharp, acute-angled edge, so that the frontal section of the mixing arms extends at an angle of less than 90 ° to the underside or to the top of the mixing arms. In particular, the settling of unfused and compacted masses on the container bottom is prevented. Other pointed shapes of the front are possible, whereby the mixing arms drive in the manner of a knife through the mix and can provide additional homogenization of the mix.

In order to achieve a higher mixing efficiency, the at least one helix may be arranged at a distance from the central shaft. Thus, the mixing tool can have at least one holding arm, which connects the lower end of the mixing spiral with the central shaft. For this purpose, holding arms, which extend in the radial direction from the central shaft to the outside, keep the helix. The holding arms can additionally contribute to the mixing. According to the invention, at least one mixing arm can be designed as a holding arm for the at least one helix, so that the helix terminates at a distance from the central shaft.

According to a further embodiment of the invention, the mixing tool, in particular the central shaft, a passage and at least one nozzle or the like for supplying gases, liquids or solids into the container. Thus, additional loosening air can be passed through the mixing tool and introduced into the mix. This ensures that the mixing components are thoroughly mixed. The loosening air can also generate additional turbulence, which further increases the mixing effect.

Advantageously, at least one of the mixing arms has at its outer end such a nozzle for supplying gases, liquids or solids into the container. The introduction of substances at the outermost point of the circular path, which describes the mixing arm, ensures that even difficult to reach areas of the container, in particular the outermost edge of the container bottom, are mixed.

The object underlying the invention is further achieved by a mixing tool for a mixing device for mixing mixed material. The features and embodiments described herein with respect to the mixing tool of the mixing apparatus apply equally to the mixing tool. Suitable mixing devices are in particular those which have a container rotatably mounted about a vertical axis, in which the mixing tool extends obliquely to the vertical axis of the container in the container, and in which the container bottom is conical.

Further developments, advantages and applications of the invention will become apparent from the following description of an embodiment and the drawings. All described and / or illustrated features alone or in any combination form the subject matter of the invention, regardless of their summary in the claims or their back references.

Show it:

1 in a sectional view of a mixing device according to a first embodiment of the invention;

2 in Perspective view the blending tool 1 ; and

3 in perspective view, the bottom section of the blending tool 2 ,

1 shows part of a mixing device 1 for mixing mix with a mixing container 2 with a high or middle axis 3 , At the top of the container 2 an opening 4 on top of which the container 2 can be filled with mix. Over the opening 4 is one on the container 1 Applicable lid 5 arranged. By means of a lifting device 6 can the lid 5 from the container 2 removed or positioned above and / or on this. In the lid 5 is the mixing tool 7 in a drive unit 8th rotatably mounted. The drive unit 8th drives the mixing tool 7 in operation, rotatory about one through the longitudinal axis of the mixing tool 7 extending axis of rotation 9 at. The drive unit 8th is on the lid 5 firmly attached, so by lifting the lid 5 also the mixing tool 7 from the container 2 can be removed. Such covers are referred to as a mixer bell.

The mixing tool 7 protrudes from the lid 5 in the interior 10 or mixing space of the container 2 and extends to the bottom of the container 11 where the mixing tool 7 at a distance to the tank bottom 11 ends, so that the mixing tool 7 not on the bottom of the container 11 supported. Further, the mixing tool 7 diagonally to the vertical axis 3 of the container 2 arranged.

The mixing tool 7 carries two mixing spirals 12 , which are helical around the axis of rotation 9 at a distance to a central shaft 13 of the mixing tool 7 from the bottom of the mixing tool 7 that the tank bottom 11 facing upwards towards the lid 5 extend.

The container 2 includes starting from the upper opening 4 a downwardly extending cylindrical portion 14 a container wall 15 , The cylindrical section 14 goes over into the tank bottom 11 towards the tapered container section 16 , where the container wall 15 in this section diagonally to the vertical axis 3 of the container 2 is inclined. The outer sections of the coils 12 become during the rotation of the mixing tool 7 on the inside of the inclined container wall section 16 guided along, they mix due to their helical shape in the container 2 from the tank bottom 11 from the top and mix this.

The tank bottom 11 is cone-shaped. Starting from corner areas or an edge area 17 in which the container wall 14 in the container bottom 11 passes over and in which the deepest points of the container interior 10 lies, the container bottom extends 11 tapering upwards. The container 2 is about a storage 18 rotatable about the vertical axis 3 stored. A drive 19 drives rollers, which are at the bottom of the container 2 attack and through which the container 2 for the mixing process about its vertical axis or axis of rotation 3 is rotationally driven.

At the bottom of the mixing tool 7 ends the mixing tool 7 at a distance to the tank bottom 11 in a section containing a number of mixing arms 20 having. The mixing arms 20 extend from the central shaft 13 essentially in the radial outward direction, but are slightly offset from the axis of rotation 9 arranged. The arrangement of the mixing arms 20 at the central shaft 13 also results from the perspective view in the 2 ,

The 2 shows the lower end of the mixing tool 7 , At the distal end or at the end of the mixing tool directed towards the container bottom 7 are six mixing arms 20 with the central shaft 13 connected. The mixing arms 20 extend in a star shape from the mixing shaft 13 and each have the same angular distance to the adjacent mixing arm. Four of the mixing arms 20 have a freestanding end. As the 2 also continues to point to the mixing tool 7 two mixing spirals 12 assembled. The mixing spirals 12 are at a distance to the central shaft 13 arranged, wherein the mixing spirals 12 over retaining arms 21 with the central shaft 13 are connected. The holding arms 21 provide an additional mixing effect.

The 3 shows in an enlarged view the distal end of the mixing tool 7 , Here are two essentially opposite mixing arms 20 as a holding arm for the lower end of the mixing spirals 12 formed, wherein the mixing helices 12 at the back of the support arms 20 end up. This ensures improved absorption of the mix. The intended for the operation direction of rotation of the mixing tool 7 around the axis 9 is by the arrow marked there 22 characterized. The frontal section 23 the mixing arms 20 has a profiled edge with a sloping surface 24 , This is how the mixing arm cuts 20 like a knife through the mix when the mixing tool 7 rotates. At the extreme end of the mixing arms 20 , which are formed as holding arms, is a nozzle 25 arranged with an unillustrated air passage in the central shaft 13 communicating so that air or other gases or even solids and the like through the central shaft 13 and the mixing arm 20 from the nozzle 25 can be introduced into the mix.

During operation, the mixing tool rotates 7 around the axis of rotation 9 while the container 2 around its axis of rotation 3 rotates. As the 1 shows, happens in each case one of the mixing arms 20 one Section of the conical container bottom 11 at the in the 1 shown right side of the container bottom 11 , The mixing arms are at a distance 26 to the surface of the container bottom 11 guided. The number of mixing arms 20 is greater than the number of mixing spirals 12 , Upon rotation of the mixing tool 7 There is strong turbulence and turbulence effects in the bottom area of the container 2 , This effect prevents material accumulation in the floor area. This is supported by the container bottom 11 has a tapered shape, which ensures that the mix moves towards the container wall 14 is directed. The nozzles 25 are in the corner area 17 of the tank bottom 11 directed. As a result, in this sensitive area, material accumulations that would otherwise not be mixed up are whirled up and directed into the mixing area. The nozzles 25 thus provide additional turbulence, which significantly improves the mixing result.

LIST OF REFERENCE NUMBERS

1

 mixing device

2

 container

3

 vertical axis

4

 opening

5

 cover

6

 lifting device

7

 mixing tool

8th

 drive

9

 axis of rotation

10

 inner space

11

 ground

12

 mixing shaft

13

 central shaft

14

 cylindrical section

15

 container wall

16

 tapered container section

17

 edge region

18

 storage

19

 drive

20

 mixing arm

21

 holding arm

22

 Rotation direction of the central shaft

23

 front section

24

 sloping surface

25

 jet

26

 distance

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 2902570 C2 [0002]
• DE 707621 A [0003]
• DE 2425727 C3 [0005]

Claims (10)

Mixing device ( 1 ) for mixing mix with one around a vertical axis ( 3 ) rotatably mounted container ( 2 ) for receiving the mixed material with an opening ( 4 ) and one through the opening ( 4 ) in the container ( 2 ) and around a rotation axis ( 9 ) rotatable mixing tool ( 7 ) with at least one mixing spiral ( 12 ) to the mix substantially along a container wall ( 15 ) of the container ( 2 ), whereby the axis of rotation ( 9 ) of the mixing tool ( 7 ) obliquely to the vertical axis ( 3 ) of the container ( 2 ), characterized in that the container bottom ( 11 ) is cone-shaped and that the mixing tool ( 7 ) at one of the container bottom ( 11 ) of the container ( 2 ) directed end several mixing arms ( 20 ) with one end at a central shaft ( 13 ) of the mixing tool ( 7 ) and by rotation of the mixing tool ( 7 ) at the container bottom ( 11 ) are guided along, wherein at least one of the mixing arms ( 20 ) at the of the central shaft ( 13 ) facing away from a freestanding end. Mixing device according to claim 1, characterized in that the number of mixing arms ( 20 ) is greater than the number of mixing spirals ( 12 ). Mixing device according to one of the preceding claims, characterized in that the mixing tool ( 7 ) at least six in the circumferential direction of the mixing tool ( 7 ) preferably evenly distributed mixing arms ( 20 ) having. Mixing device according to one of the preceding claims, characterized in that the mixing tool ( 7 ) on a container lid ( 5 ) and that the container lid ( 5 ) a drive ( 8th ) for the mixing tool ( 7 ) wearing. Mixing device according to one of the preceding claims, characterized in that the mixing arms ( 20 ) in the direction of rotation ( 22 ) an inclined surface ( 23 ) exhibit. Mixing device according to one of the preceding claims, characterized in that the mixing arms ( 20 ) a profiled, in particular sharp, acute-angled edge ( 24 ) exhibit. Mixing device according to one of the preceding claims, characterized in that at least one mixing arm ( 20 ) as a holding arm for the at least one mixing spiral ( 12 ) is trained. Mixing device according to one of the preceding claims, characterized in that the mixing tool ( 7 ) a passage and at least one nozzle ( 25 ) or the like for supplying gases, liquids or solids into the container ( 2 ) having. Mixing device according to one of the preceding claims, characterized in that at least one of the mixing arms ( 20 ) at its outer end a nozzle ( 25 ) for supplying gases, liquids or solids into the container ( 2 ) having. Mixing tool ( 7 ) for a mixing device ( 1 ) for mixing mix with a container ( 2 ) for receiving mixed material, wherein the mixing tool ( 7 ) at least one mixing helix ( 12 ) to the mix by rotation of the mixing tool ( 7 ) substantially along a container wall ( 15 ) of the container ( 2 ), characterized in that the mixing tool ( 7 ) at one of the container bottom ( 11 ) of the container ( 2 ) directed end several mixing arms ( 20 ) with one end at a central shaft ( 13 ) of the mixing tool ( 7 ) and by rotation of the mixing tool ( 7 ) are guided along the ground, wherein at least one of the mixing arms at the of the central shaft ( 13 ) facing away from a freestanding end.

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