EP3189888B1 - Mixing device - Google Patents

Description

The present invention relates to a mixing device for mixing material to be mixed, such as dry and/or moistened solids and/or liquids, with a container for receiving the material to be mixed with an opening and a mixer lid that can be positioned on and/or over the opening.

Generic devices are used to mix substances such as flour, dough, porridge, yoghurt or other powdery, granular, pasty and/or liquid mixes. The container is filled with the material to be mixed, and a rotating agitator or mixing tool, such as a mixing shaft or the like, which is or can be arranged in the container, thoroughly mixes the material to be mixed.

Some mixing devices provide for the container to be rotated about its vertical axis relative to the lid during the mixing process, with the lid carrying the mixing tool and often also a drive for rotating the mixing tool. The mixing tool is removed from or introduced into the container by raising or lowering the lid. The advantage of these covers, generally referred to as mixer bells, is in particular that the container can be used not only as a pure mixing container but also as a transport container, in that the container is removed from the mixing device after the mixing process. The lid can also carry other devices, such as a chopper arranged on a rotatable shaft for chopping up the material to be mixed.

Such a mixer is, for example, from DE 33 14 727 C2 is known which has a mixing device with a mixing tool attached to the lid describes. The container is rotatably mounted on a mixer frame and the container opening at the top, through which the material to be mixed is introduced into the container, is closed by the lid, which is placed over or on the opening. The mixing tool extends through the lid into the container. A sliding seal bearing is provided between the lid and the rotatable container. The lid has a recess on the underside facing the container opening, and the top rim of the container is fitted into the recess. The problem here is the centering of the lid in relation to the container. The lid must sit correctly on the container so that it does not run out of true when the mixing tool mixes the material to be mixed by rotating and the container rotates around its vertical axis.

An alternative mixing device according to the preamble of claim 1, which can be used for paints, for example, is from U.S. 2,219,706A known. Next is from the U.S. 2008/279040 A1 a mixer for frozen beverages is known in which a lid can be placed sealingly on a container.

Especially in cases where the container is also used as a transport container, a quick and correct positioning of the lid and the mixing tool in the container is of crucial importance. If the lid is not positioned correctly on the hopper, mix may leak out. In the worst case, the mixing tool hits the inner wall of the container, which not only damages the container and impairs the quality of the material to be mixed, but above all creates a risk of explosion due to sparks or heating. In addition, the possible uses in the context of automation are limited because the correct positioning of the lid must always be done by hand to ensure that the lid is properly centered on or on the container.

It is the object of the present invention to propose a mixing device that enables the mixer lid to be positioned more easily and efficiently.

This object is achieved by a mixing device having the features of claim 1.

The invention provides that a guide is provided for positioning the mixer cover over the opening, that the mixer cover is mounted in a floating manner on the guide, so that the mixer cover can move transversely to the guide within a predetermined range of movement, and that the mixer cover has centering means in order to center the mixer lid on the container.

The floating bearing ensures easy, safe and efficient positioning of the mixer lid on the container while being centered to ensure a proper fit. This ensures that the lid is correctly aligned with the vertical axis of the container, which can also be the axis of rotation of the container. This is particularly true when it comes to a mixer bell, which also carries the stirring tool. Due to the floating storage, this is also properly positioned in the container. On the one hand, this increases the efficiency of the mixing process and, on the other hand, it prevents the stirring tool from coming into contact with the container wall. The floating bearing adapts to the normal manufacturing tolerances that can occur with the containers. This makes the system particularly suitable for automated processes, such as automated lowering of the mixer lid.

The centering means have three engagement sections, e.g. in the form of guide surfaces, which are designed in such a way that they center the mixer lid on the container when the engagement sections are at least partially and/or partially in contact with the container, preferably the outer container wall, and are thereby relative to the container , preferably in the direction of the bottom of the container. This can happen when the mixer lid is lowered onto the container. According to the centering can also be done when the mixer lid on the container in a first final position is brought. In this case, the centering means can, for example, comprise centering units which can be moved in the vertical direction relative to the container and on which the guide surfaces are formed. A plurality of centering means can be provided which successively engage the container wall when they are moved relative to the container.

The mixer cover is moved relative to the guide by the centering means in a direction that does not correspond to the guide direction of the guide. The mixer lid therefore does not have to be placed on the container. The floating bearing allows relative shifts or movements between the mixer cover and the guide and can be formed, for example, by two sliding surfaces that can be moved relative to one another, one sliding surface being connected to the guide and guided purely vertically and the second sliding surface on the mixer cover provided and is movable relative to the first sliding surface in the horizontal direction. In a direction transverse to the direction in which the two sliding surfaces can be displaced relative to one another, the second sliding surface is preferably firmly connected to the first sliding surface or at least supported on it, so that a movement in the vertical direction from the first sliding surface to the second sliding surface is transferred. The floating bearing is designed in such a way that the possible range of relative displacements takes place within a predetermined range with fixed limits.

The guide is designed in such a way that it guides the mixer lid towards the opening. It can be formed, for example, by a guide rail or the like, which initially excludes a transverse movement of the mixer cover. This basically carries the risk that the lid will not be correctly positioned over the container. The floating bearing that connects the mixer cover to the guide allows transverse movements and compensates for the possible deviations that can occur during operation.

The range of motion within which the mixer cover can move relative to the guide can be a horizontal range of motion that lies in a plane perpendicular to the vertical axis of the container.

The guide is preferably a vertical guide, but it can also be an inclined guide. The container lid can be coupled to the guide by means of a coupling device, the coupling device being part of the floating bearing. The guide preferably comprises a vertical guide lifting frame. This can include one or more guide rails that are aligned vertically.

The guide can also comprise a lifting device, or a lifting device can be provided on the guide which raises or lowers the cover. The lifting device can include pneumatic or hydraulic drives and/or have a chain hoist.

The mixer lid preferably hovers over the container during operation. It can then be positioned at a preferably small distance from the container opening in order to avoid contact between the container and the mixer lid when the container rotates relative to the mixer lid.

According to a further embodiment, it is provided that the mixer cover has at least one mixing tool and is therefore designed as a mixer bell. This can, for example, be a mixing shaft with a mixing helix, but also a chopper or the like. In this case, the container is preferably mounted such that it can rotate about its vertical axis, and a drive is provided for driving the container in rotation about the vertical axis.

According to a further embodiment, the floating bearing comprises at least one bolt which is connected to the guide and at one end of which a washer is arranged. The disc is in turn arranged on a holding section of the mixer cover, so that the disc supports the holding section, and thus the mixer cover, in the vertical direction, with the holding section being designed in such a way that the disc can move in a predetermined range of motion relative to the holding section transverse to the guide direction .

The terms horizontal and vertical are to be understood in such a way that they essentially define two mutually perpendicular directions of the mixer cover and the guide. In this case, the bolt and the washer form a coupling device, via which the mixer cover is coupled to the guide for lowering the mixer cover. The mixing device preferably comprises a plurality of retaining bolts for lifting and lowering the mixer cover. The bolt is guided in the guide and can move in the vertical direction while being prevented from moving in the horizontal direction. The vertical guide lifting frame is rigid, whereas the mixer bell is slidably guided in the vertical direction on the vertical guide lifting frame and is mounted floating in the horizontal direction relative to the vertical guide lifting frame. The bolts serve as suspension bolts. The floating bearing is preferably designed in such a way that the possible freedom of movement can take place in a range of +/- 40 mm.

According to a further embodiment, the holding section can comprise an annular space in which the disk is arranged, the inner diameter of the space being larger than the diameter of the disk. In other words, the holding section can be circular in shape. The disc can also have a circular shape. The pane may be arranged such that the holding portion abuts the pane. The holding section may have a circular opening through which the pin extends towards the guide, the circular opening in the holding portion being larger than the diameter of the pin so that the holding portion can move in a horizontal direction relative to the pin. The holding portion of the mixer lid is larger than the holding portion of the disc, so that the holding portion can move in the horizontal direction relative to the disc. Preferably, the mixer lid is floating on three sections on the guide. Preferably, these three sections are evenly distributed around the vertical axis of the container.

The centering means comprise at least three centering units which are connected to the mixer cover and which are distributed around a vertical axis of the tank. The centering units each have an engagement section which is designed to rest against the container wall. The engagement portions cause the mixer lid to be properly aligned and direct the lid to the correct position relative to the container when the engagement portion is slid along the container wall. The engaging portion is preferably formed to extend in the vertical direction to gently urge the mixer lid into position.

It has proven to be particularly advantageous if the centering units are conically shaped, at least in sections. In a further development of this idea of the invention, the conical section can transition into a cylindrical section in the vertical direction, so that a defined end position of the mixer cover is assumed relative to the container.

A further embodiment of the invention provides that the centering units are rotatably mounted so that they can rotate about their vertical axis. This type of centering ensures that the container is effectively centered relative to the Mixer lid can rotate while maintaining contact between the centering unit and the container. The centering units can be shaped like a drum or roller, for example.

On the outer wall of the container, the container can have one or more radially outwardly extending rims, edges, projections or the like, which can serve, among other things, for the positioning of the centering units.

A further embodiment of the invention provides that the mixer cover has a cylindrical ring element on the side facing the container. This can be coupled to the mixer cover in such a way that the ring element can be placed on a container edge surrounding the opening by lowering the mixer cover. This so-called “shot” can be, for example, a sheet metal ring that initially hangs on the mixer bell in the starting position. When the mixer lid is lowered, the section touches the edge of the container and is decoupled from the mixer lid. Fastening means familiar to the person skilled in the art, such as a suspension, hooks, screw connections, quick-release fasteners or the like, can be used to couple the ring element and mixer cover. The ring element effectively increases the container wall. When the container rotates, it is rotated about its central axis. During operation, a gap is preferably provided at least in sections between the mixer cover and the ring element. This lies horizontally between the bottom of the mixer cover and the top of the ring element, creating a defined air gap that contributes to dust aspiration.

According to a further embodiment of the invention, means are provided for bracing the mixer cover over the container. These can be used to prevent the mixer bell or the mixer cover from tipping over. For this purpose, the means for bracing at least one pivotable Have roller, which can be pivoted against the container, preferably against a molded or attached to the outer wall of the container board and / or a peripheral edge. The roller is firmly connected to the mixer cover, preferably to the centering units. When the roller is pivoted against the rim of the container, it can effectively prevent the lid from tilting relative to the container.

According to the invention, the means for bracing can have a pivoting/lifting cylinder device or the like for pivoting the roller, so that the degree of automation of the system can be increased. The roller can then be swiveled in directly on the centering unit from below against the container, shelf or flange and preferably clamped pneumatically. According to the invention, the centering means can each comprise a second roller arranged to bear against the top of the shelf or the like.

Furthermore, the mixing device can have an adjustment unit, such as a pneumatic actuator or the like, which is set up to bring the mixer lid back into a relative zero position relative to the guide after it has been removed from the container. This ensures that the mixer lid can move relative to the guide within the predetermined range of movement.

Further advantages, features and exemplary embodiments of the invention result from the following description of an exemplary embodiment and the drawings. All of the features described and/or illustrated form the subject matter of the invention, either alone or in any combination, even independently of their summary in the claims or their back-references.

Fig. 1

in einer Schnittansicht eine Mischvorrichtung nach einer ersten Ausführungsform der Erfindung;

Fig. 2

einen Ausschnitt der Mischvorrichtung aus Figur 1; und

Fig. 3

einen weiteren Ausschnitt der Mischvorrichtung aus Figur 1 in perspektivischer Ansicht.

Show it:

1

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

2

a section of the mixing device figure 1 ; and

3

Another section of the mixing device figure 1 in perspective view.

The one in the figure 1 The mixing device 1 shown comprises a mixing container 2 with a vertical axis 3. At the upper end, the container 2 has an opening 4 over which a cover 5 is arranged. The container 2 can be filled with material to be mixed (not shown) through the opening 4 . A mixing tool in the form of a mixing shaft 6 , which has two mixing helices 7 for mixing the material to be mixed, is arranged inside the container 2 . The mixing shaft 6 extends from a bottom area 8 of the container 2 obliquely to the vertical axis 3 through the cover 5, where it is held by the cover 5 or mounted on it. A drive 9 is attached to the mixer cover 5 and drives the mixing shaft 6 in rotation about an axis of rotation 9a extending in the longitudinal direction of the mixing shaft 6 , so that the material to be mixed is mixed by the mixing spirals 7 . By lifting the mixer lid 5 upwards (away from the opening 4), the mixing shaft 6 is also removed from the container 2. It is then possible to replace the container 2 with another container that is filled with the material to be mixed. The lid 5 with the mixing shaft 6 can then be lowered onto the new container, as a result of which the mixing shaft 6 is introduced into the container.

The container 2 has an outer casing or an outer container wall 10 . The mixer lid 5 extends over an outer edge of the container 2 and ends in a section 11 on which the mixer cover 5 is mounted in a floating manner on a guide 12 . The guide 12 includes a traversing element 13 in the form of a frame and a base element 14 in the form of a vertical guide. The traversing element 13 is guided vertically in the base element 14, so that the traversing element 13 can only move in the vertical direction but not in the horizontal direction. Pivoting movements of the displacement element 13 are also excluded. The connection between the moving element 13 and the base element 14 is designed as a guide rail connection, so that the unit is designed as a vertical guide lifting frame.

A drive 15 (lifting device) for raising and lowering the mixer cover 5 is arranged at the upper end of the base element 14 . This is connected to the drive 15 via a chain 16 .

The figure 1 1 shows the mixing device in a ready-to-use state, in which the mixer lid 5 is positioned above the opening 4 of the container 2. FIG. Between the mixer cover 5 and the opening 4 there is a ring element 16 which is designed as a sheet metal ring.

The container wall 10 comprises an upper container section with a cylindrical outer container wall 17 and a container wall section 18 adjoining in the downward direction with a conical inner shape, which tapers towards the container bottom 8 .

The container 2 is rotatably mounted on a bearing 19 so that it can rotate about its vertical axis 3 . A drive 20 which acts on the underside of the container 2 serves to drive the container in rotation about its vertical axis 3 .

In an outer area of the mixer cover 5 there are centering means 21 which ensure that the mixer cover 5 is centered on the container when it is lowered onto the container 2 . A total of three centering means 21 distributed uniformly around the vertical axis 3 are provided in the exemplary embodiment shown.

As the figure 2 shows, the floating bearing 11 comprises a bolt 22 which is firmly connected to the traversing element 13 and is thus guided vertically in the guide rails in the base element. At the lower end of the bolt 22 a circular disc 23 is attached. The bolt 22 extends through an opening 24 formed in the mixer lid 5, the inner diameter of which is larger than the outer diameter of the bolt 22. The disc 23 is arranged in a space 25 with a circular cross-section. The outside diameter of disc 23 is smaller than the inside diameter of circular space 25.

The diameter of the opening 24 is in turn smaller than the outer diameter of the disc 23, so that a holding section 26 is formed in the mixer cover 5, via which the mixer cover 5 bears against the disc 23 or is supported. The holding section 26 also forms part of the upper wall of the space 23. The lower wall 27 of the space 25 is formed below the disk 23. FIG. Lower wall 27 and holding section 26 are designed as sliding surfaces, on which disc 23, which is also designed as a sliding surface, can slide within space 25 in the horizontal direction.

Due to the sliding surfaces and the larger inner diameter of the space 25, the opening 24 and the outer dimension of the disc 23, the mixer cover 5 can move in the horizontal direction relative to the bolt 22 until an outer portion of the disc 23 on an inner wall portion of the space 25 to the plant comes. In the vertical direction, a movement of the bolt 22 transferred to the holding section 26 of the mixer cover 5 via the disk 23 . In this way, the mixer cover 5 can be moved in the vertical direction, while the mixer cover 5 is at the same time floating relative to the guide in the horizontal direction.

The centering means 21 each comprise a rotatable centering unit 28 with a cylindrical section 29 and a conically shaped engagement section 30 adjoining it at the bottom , so that it comes to rest on the underside of a rim 36 protruding radially outwards from the container wall 10 . The centering unit 28 is also mounted such that it can rotate about the vertical axis 33 .

The shaft 32 is part of a pneumatic actuator 34 and is designed as a piston in the upper section. By controlling hydraulic air in and out of a chamber 35, the shaft 32 can be moved up and down. When the mixer lid 5 is lowered onto the opening of the container, the centering unit 28 can be moved downwards relative to the mixer lid 5 by means of compressed air. In the process, the downwardly tapering engagement section 30 first comes into contact with the rim 36 of the container 2 . As a result of a movement of the centering unit 28 downwards, the inclined guide surface 30 moves the cover 5 in the horizontal direction. The floating bearing 11 allows the mixer cover 5 to move in the horizontal direction relative to the guide. Because at least three centering units are distributed over the circumference of the container 2 on the mixer lid 5, at least one of the centering units always comes into contact first with an outer edge or the rim 36 of the container 2 and begins to move the mixer lid 5 in a horizontal direction. so that finally all centering units in come into contact with the container 2. The cooperation of the individual centering units causes the mixer lid 5 to be centered on the container 2.

Next to the first roller 31, a second roller 39 is rotatably mounted on the mixer lid 5 and contacts a running surface on the top of the shelf 36 when the lid is lowered onto the container 5. The first roller 31 can pivot when the lid 5 is centred, contacts a running surface on the underside of the shelf 36 and can then be braced against the shelf 39, effectively avoiding tipping of the lid over the opening in use becomes.

In order to bring the mixer cover 5 back into a central zero position in relation to the guide 12 after the mixing process, ie the disc 23 is concentric to the opening 24 again figure 2 to bring, the mixing device has a plate slide 40. This is in figure 3 shown. In the example shown, a disk slide is provided on each centering unit. The disk slide 40 has an arm 41 that can be moved in the horizontal direction. The arm 41 has a trough-shaped depression 43 for receiving the sleeve 42 . The arm 41 uses this to grip the sleeve 42 in the horizontal direction and displaces the mixer cover 5 in the floating bearing 11 relative to the displacement element 13. The interaction of all disk slides moves the mixer cover 5 back into a central zero position.

Reference List

1

mixing device

2

container

3

Vertical axis / axis of rotation

4

opening

5

Lid

6

mixed shaft

7

helix

8th

floor area

9

drive

9a

axis of rotation

10

container wall

11

Floating storage

12

guide

13

traversing element

14

basic element

15

drive

16

ring element

17

cylindrical container wall section

18

conical container wall section

19

storage

20

drive

21

centering means

22

bolt

23

disc

24

opening

25

Space

26

Holding section / upper sliding surface

27

lower sliding surface

28

centering unit

29

cylindrical section of the centering unit

30

conical section of the centering unit

31

role

32

Wave

33

vertical axis

34

actuator

35

chamber

36

board

39

role

40

plate slider

41

poor

42

sleeve

43

deepening

Claims (11)

1. A mixing device (1) for the mixing of mixing material, having a container (2) for accommodating the mixing material, with an opening (4) and a mixer lid (5), which can be positioned over the opening (4),

   a guide (12) being provided for positioning the mixer lid (5) over the opening (4),

   and the mixer lid (5) having centring means (21) in order to centre the mixer lid (5) on the container (2),

   characterized in that the mixer lid (5) is mounted on the guide (12) in a floating manner, so that the mixer lid (5) can move within a predetermined movement range transversely to the guide (12), and in that the centring means (21) comprise at least three centring units (28), which are distributed around a vertical axis (3) of the container (2) and in each case have an engagement section (30), which is constructed to rest on the container outer wall (10), wherein the centring unit (28) can be moved relatively to the mixer lid (5) in the vertical direction.
2. The mixing device according to Claim 1, characterized in that the centring means (21) have one or more engagement sections (30), wherein the engagement sections (30) are designed in such a manner that they centre the mixer lid (5) on the container (2) if the engagement sections (30) rest at least partially on the container (2), preferably the outer container wall, and move relatively to the container (2).
3. The mixing device according to Claim 1 or 2, characterized in that the mixer lid (5) has at least one mixing tool (6).
4. The mixing device according to one of the preceding claims, characterized in that the guide (12) has a vertical guide travel frame.
5. The mixing device according to one of the preceding claims, characterized in that the floating bearing (11) comprises at least one bolt (22), which is connected to the guide (12) and at the one end of which a disc (23) is arranged, which is arranged on a holding section (26) of the mixer lid (5) such that the disc (23) supports the holding section (26) in the vertical direction, wherein the holding section (26) is designed such that the disc (23) can move transversely within a predetermined movement range relatively to the holding section (26).
6. The mixing device according to Claim 5, characterized in that the holding section (26) comprises an annular space (25), in which the disc (23) is arranged, and in that the internal diameter of the space (25) is greater than the diameter of the disc (23).
7. The mixing device according to one of the preceding claims, characterized in that the centring units (28) are conically shaped at least in certain sections.
8. The mixing device according to one of the preceding claims, characterized in that the centring units (28) are mounted in a rotatory manner.
9. The mixing device according to one of the preceding claims, characterized in that centring units (28) comprise at least one roller (31) which can be pivoted towards a rim (36) of the container (2).
10. The mixing device according to one of the preceding claims, characterized in that the mixer lid (5) has a cylindrical ring element (16) on the side facing the container.
11. The mixing device according to Claim 10, characterized in that a gap is provided at least in certain sections between the mixer lid (10) and the ring element (16).

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