EP0801974A1 - Device for homogenizing and/or dispersing a flowable material - Google Patents

Abstract

The mixer for homogenising/dispersion liquids or pastes has a rotary mixer (4) at the base of the vessel. Material is driven by centrifugal action into the product chamber (10) from where it can recirculate to the vessel. A plate (15), concentric with a stator (7), which guides it, is notched at its circumference so that rotation opens, or closes, the recirculation passages (12). When passages (12) are closed the material is diverted to an external pump.

Description

The invention relates to a device for homogenizing and / or dispersing a flowable material, which is intended in particular for the production of viscous and semi-solid products, such as ointments, pastes, gels or doughs in the field of pharmacy, chemistry, cosmetics or the food industry is.

From EP 0 204 294 B1 a device for homogenizing and / or dispersing a flowable material with a container is known, in the bottom area of which a homogenizing and dispersing device is provided with a rotor / stator arrangement, each having through openings through which the Rotor suctioned material is driven outwards and exits radially outside of the stator in a product space enclosed by a housing. To switch over from a circulation homogenization or mixing or an internal circulation and a flow homogenization or mixing and vice versa, a shut-off device or a closing device for an outlet opening for the material in the area of the container bottom radially outside the stator is provided, which covers a covering the outlet opening Has plate and a lifting and lowering device for the plate. The lifting and lowering device for the plate is sealed through the bottom of the container. These seals can be difficult, and there is also one additional auxiliary energy required to operate the lifting and lowering device. The sealing bushings also tend to product deposits, which lead to a risk of contamination. Due to the lifting and lowering device provided, separate devices for the suction of additives, such as powder or the like, must be provided in the suction zone of the homogenizing and dispersing device, which is structurally relatively complex.

Furthermore, a homogenizer for the production of flowable products is known, for example, from EP 0 290 033, in which a plate is arranged in the center of the container base and has an access opening for the rotor / stator arrangement located underneath. Between the rim of the plate and the bottom of the container there is always an annular gap with a small cross section, which acts as a throttle opening. Since this annular gap cannot be closed even when the flow is mixed and homogenized, the pumping capacity is reduced by leakage losses. Since the annular gap must have a small cross section, highly viscous products cannot be conveyed back into the container near its bottom via this annular gap. This annular gap also presents difficulties when cleaning the device, and there are also difficulties with regard to cleaning a shut-off device in the region of a product outlet downstream and radially outside the rotor / stator arrangement. This shut-off device is used to switch over for continuous operation and internal circulation operation.

Furthermore, there is a device for homogenizing and / or dispersing a flowable material (DE-GM 84 28 385.8), in which the homogenizing and dispersing device is arranged in the center of the container bottom and can be raised and lowered. When the homogenizing and dispersing device is raised, an internal circulation can be realized and when the homogenizing and dispersing device is lowered, continuous operation can be achieved. Here, however, the entire homogenizing and dispersing device must be equipped with the appropriate additional aids are raised and lowered, which is extremely expensive to construct.

In the description and the claims, "continuous operation" is used when flow mixing and homogenization is carried out and, if necessary, external circulation takes place and the shut-off device is closed, and "internal circulation" or "internal circulation operation" when circulation mixing occurs or -homogenization is realized, in which the shut-off device is open and the product stream is conveyed back into the container after passing through the homogenizing and dispersing device.

In contrast, the invention aims to provide a device for homogenizing and / or dispersing a flowable material while overcoming the previously described difficulties and in particular overcoming sealing problems and possible contamination risks, which device provides a switch from internal circulation mixing or - in a structurally simple and operationally reliable manner. Homogenization and flow mixing and homogenization in the most energy-efficient manner possible and residue-free automatic cleaning of the entire device is made possible.

According to the invention, a device for homogenizing and / or dispersing a flowable material with a container is provided, in the bottom area of which a homogenizing and dispersing device is provided with a rotor / stator arrangement, each of which has through-openings through which the air sucked in by the rotor Is well driven outwards and exits radially outside of the stator in a product space enclosed by a housing, a shut-off device in the open position an internal circulation mixing or homogenization with return of the goods into the container near its bottom and in the closed position a flow mixing and Homogenization, if necessary, by pumping (external Circulation) allowed. This device is characterized in that the shut-off device comprises a disc which is rotatably mounted centrally on the stator and which has recesses on the outer peripheral edge which are aligned with peripheral recesses on the stator in the open position and are closed by turning the disc in the closed position. The peripheral recesses of the disk and / or the stator are preferably arranged regularly.

Thanks to the design of the shut-off device according to the invention, a switchover from continuous operation, that is to say with flow mixing and homogenization, and internal circulation operation, that is, circulation mixing or homogenization without the implementation of mechanical force transmission elements by the device for homogenizing and / or dispersing or the container is possible , so that sealing problems can be avoided more effectively. The actuation of the shut-off device for switching is also free of any risk of contamination which may be caused thereby. Therefore, the device according to the invention can also be reliably cleaned completely and automatically without residues. Furthermore, material deposits and crust formation can be avoided, since all parts of the homogenizing and dispersing device are constantly and adequately washed by the material. In addition to a rapid changeover from continuous operation and internal circulation operation, this changeover process is also realized in conjunction with extremely low auxiliary energy thanks to the shut-off device according to the invention. Since the recesses on the outer peripheral edge of the disk of the shut-off device are assigned corresponding to the circumferential recesses on the stator, a slight twisting movement of the disk rotatably mounted centrally on the stator is sufficient to either bring the shut-off device into the closed position, in which the recesses are closed, or into an open position to bring in which the assigned recesses are aligned, so that an internal circulation operation with return conveying into the container can be realized. Since no good can pass through in the closed position of the shut-off device, Avoid leakage losses during continuous operation, and the pumping capacity is available without restriction for continuous operation. Furthermore, the shut-off device can be reliably cleaned in the open position without difficulty, and thanks to the design of the shut-off device according to the invention there is also no risk of deposits in its effective area.

In particular, the shut-off device is arranged in the vicinity of the bottom of the container. This enables the product flow to be reliably shut off as close as possible to the point of exit to the container during continuous operation.

According to a preferred embodiment, the rotatable disk has, preferably regularly, arranged webs which protrude into the product space adjoining the outlet from the rotor / stator arrangement and by means of which the shut-off device can be brought into its open and closed position and in each case can be held there is. It is thus possible to actuate the shut-off device in a hydrodynamic manner, since the material flow exiting the stator with a certain angular momentum hits the webs attached to the circumference of the rotatable disk. As a result, the shut-off device is held reliably in its respective open position or closed position. If the direction of rotation of the rotor of the rotor / stator arrangement is reversed, the direction of action of the angular momentum is reversed and the rotatable disk is brought into the corresponding other position by the flow forces of the crop flow and held there.

In an alternative embodiment, permanent magnets are attached to the webs, which cooperate with a ring of permanent magnets arranged outside the housing in such a way that opposing permanent magnets attract each other and thereby impart a torque to the disk without contact. Thus, by turning the ring arranged outside the housing, there is a contactless switchover between continuous operation and internal circulation operation.

In order to increase the mixing during the internal circulation operation, the product flow is returned into the container tangentially to the container bottom by means of a deflection device. As a result, the product stream returned to the container during the internal circulation operation can be separated from the intake stream of the homogenizing and dispersing device, which is directed centrally in the bottom region of the container. Short-circuit flows between the product flow returned to the interior of the container and the suction area of the homogenizing and dispersing device can be avoided. Furthermore, this deflection device also allows the angular momentum imparted to the product stream by the rotor of the rotor / stator arrangement to be reduced before the product stream is returned to the container during the internal circulation operation. In this way, unfavorable rotational flows of the material flow inside the container can be avoided.

Furthermore, since there are no lifting and lowering shut-off devices in the device according to the invention, a feed device for additives such as powder, in particular a powder suction device, can be integrated into the homogenizing and dispersing device. For this purpose, in the device according to the invention, an intake pipe, which opens into the intake area of the homogenizing and dispersing device and penetrates the stator, is provided for the supply of liquids, powder or the like, which, in order to avoid deposits in the supply area, has a defined leakage gap between the pressure side and the suction side of the Homogenizing and dispersing device.

Fig. 1

eine vergrößerte Ausschnittsansicht einer Vorrichtung zum Homogenisieren und/oder Dispergieren eines fließfähigen Guts in einem Behälterbodenbereich,

Fig. 2

eine schematische Draufsicht auf eine drehbare Scheibe einer Absperreinrichtung in Figur 1 unter Zuordnung zum schematisch in gebrochener Linie dargestellten Stator, und

Fig. 3

eine Figur 1 ähnliche vergrößerte Schnittansicht einer Ausführungsvariante einer Vorrichtung zum Homogenisieren und/oder Dispergieren eines fließfähigen Guts.

The invention is explained below with reference to preferred embodiments with reference to the accompanying drawings. It shows:

Fig. 1

2 shows an enlarged sectional view of a device for homogenizing and / or dispersing a flowable material in a container bottom area,

Fig. 2

2 shows a schematic plan view of a rotatable disk of a shut-off device in FIG. 1 with assignment to the stator shown schematically in broken lines, and

Fig. 3

an enlarged sectional view similar to Figure 1 of an embodiment of a device for homogenizing and / or dispersing a flowable material.

In the figures of the drawing, identical or similar parts are provided with the same reference symbols.

A first preferred embodiment of a device for homogenizing and / or dispersing a flowable material, generally designated 1, is explained with reference to FIGS. 1 and 2. This comprises a schematically indicated container 2, in the bottom region 3 of which a homogenizing and dispersing device, generally designated 4, is arranged, preferably below the bottom region 3 of the container 2. The homogenizing and dispersing device 4 comprises a rotor 5 which is fixedly connected to a shaft 6 which is driven by a motor (not shown in more detail) which is preferably provided further down in the illustration in FIG. The rotor 5 forms several passage openings for the flowable material which are distributed in the circumferential direction and are not shown in detail. Furthermore, the homogenizing and dispersing device 4 comprises a stator 7, which is provided in a stationary manner on the container 2 in the bottom region 3. The stator 7 also has through openings (not shown) for the flowable material. The flowable material, as illustrated by an arrow A in FIG. 1, is drawn in from above in the central area of the homogenizing and dispersing device 4 in the suction area via the stator 7 and is then homogenized by the arrangement comprising the rotor 5 and the stator 7 - And dispersing device 4 and the passage openings present there are driven radially outward to the pressure region 9 in a product space 10, which from a housing 11th is enclosed. A passage gap 12 (see left-hand side in FIG. 1) is formed between the stator 7 and the bottom region 3 of the container 2, which has a deflection device 13, which in the example shown is formed on the stator 7, through which the internal passage gap 12 is open when the passage gap 12 is open Circulation operation of the product stream tangential to the bottom region 3 of the container 2 is conveyed back into the same after passing through the homogenizing and dispersing device 4. This passage gap 12 is assigned a shut-off device 14, which comprises a disc 15 which is rotatably mounted centrally on the stator 7. According to FIG. 2, the disk 15 preferably has regularly arranged recesses 16 on the circumferential edge, and circumferential recesses, which are preferably not regularly shown, are also provided on the circumferential edge of the stator 7. As can be seen from Figure 1, the recesses 16 of the disc 15 are aligned with the associated recesses on the circumferential edge of the stator 7, so that the passage gap 12 is released, and the flow of material after passing through the homogenizing and dispersing device 4 and out of the product space 10 at the pressure area 9 via the aligned recesses 16 and via the deflection device 13 tangential to the bottom area 3 of the container 2 and the passage gap 12 to the container in order to realize an internal circulation operation.

As can also be seen from FIG. 1, the rotatable disk 15 has webs 17 on the circumference, preferably arranged regularly, and projecting into the product space 10. In the hydrodynamic actuation of the shut-off device 15 illustrated in FIG. 1, it comes from the homogenizing and dispersing device 4 emerging product stream with a certain angular momentum on the webs 17, so that depending on the direction of rotation of the rotor 5 by means of the action of the webs 17 by the product stream, the disk 15 is reliably held in the open position shown, for example, in FIG. If the direction of rotation of the rotor 5 is now reversed, the product stream emerging from the homogenizing and dispersing device 4 causes the webs 17 are applied in such a way that the disc 15 is rotated slightly so that the recesses 16 of the disc 15 and the recesses on the stator 7 are no longer in alignment and the shut-off device 14 assumes its closed position. In this closed position, a continuous operation, if necessary with external circulation, is then carried out, in which the material flow leaves the device via an outlet 18 and is conveyed, for example, to a collecting container (not shown), or in turn by means of a pumping line at a greater height into container 2 is initiated in the event of external revolution. In this closed position, the disc 15 is also held reliably by the product stream that strikes the webs 17. In this embodiment, the shut-off device 14 is thus adjusted into its open position and into its closed position in a hydrodynamic manner.

A device for additionally introducing an additive, for example in the form of a powder suction 21, is shown at 20 in FIG. Of course, other liquid or solid substances or mixtures thereof can also be supplied in the same or a similar manner. The feed line takes place in the suction area 8 of the homogenizing and dispersing device 4. This device 20 for the additional introduction of an additive, such as powder or the like, includes, among other things, an suction pipe 22 integrated in the homogenizing and dispersing device 4. The suction pipe 22 passes through the stator 7 in an area above the rotor 5 and is sealed there. This suction pipe 22 opens into the suction area 8 of the homogenizing and dispersing device 4. This suction pipe 22 has a leakage gap 23 between the suction area 8 and the pressure area 9, formed by the product space 10 and the homogenizing and dispersing device 4. This defined leakage gap 23 maintain a targeted leakage flow between the pressure area 9 and the suction area 8 of the homogenizing and dispersing device 4 in order to keep the device 20 free from deposits for the additional introduction of an additive, when a suction valve of this device 20 is closed. This avoids contamination when an additive is added by means of suction.

With reference to FIG. 3, an embodiment variant of a device for homogenizing and / or dispersing a flowable material, denoted overall by 1 ', is explained. For reasons of clarity, the same or similar parts as in the preferred embodiment described above are provided with the same reference numerals and are not explained again.

As a significant difference from the embodiment according to FIG. 1, the webs 17 'have permanent magnets 30 and outside of the housing 11 there is a ring 31, which likewise comprises permanent magnets 32. The assignment of the permanent magnets 30 and the permanent magnets 32 is made in such a way that the poles of opposing permanent magnets 30, 32 attract each other. If the ring 31 arranged outside the housing 11 is now rotated, the permanent magnets 30 run on the webs 17 'due to the attraction movement and impart a torque to the rotatable disk 15. Thus, in this embodiment, the disk 15 can be brought into the open or closed position of the shut-off device 14 in a contactless manner by rotating the ring 31. Thus, in this embodiment, too, no additional auxiliary drive energy and no additional auxiliary drive devices are required for actuating the shut-off device 14.

Of course, the invention is not limited to the details described above, but numerous changes and modifications are possible, which the person skilled in the art will make if necessary, without departing from the inventive concept. In particular, the arrangement and the mounting of the rotatable disk 15 can be carried out in a different way than that shown be realized. It is essential, however, that a shut-off device 14 is obtained by means of a fixed plate and a plate or disk 15 that can be rotated for this purpose at the outlet area for returning in the area of the bottom 3 of the container 2, which shut off a passage gap for the changeover from continuous operation to internal circulation operation or can release. The switchover is carried out in the most energy-saving manner possible with a short switching travel, for example by only slightly rotating the rotatable disk with respect to a fixed plate or a corresponding design of the stator 7. Since the passage gaps 12 of this shut-off device 14 are reliably closed during continuous operation, pumping over may be necessary can be effectively implemented in external continuous operation without leakage losses. As a result, the efficiency of pumping devices that may be provided can be improved. In particular, however, such a device 1, 1 'allows processing to be carried out reproducibly and contamination to be effectively avoided. In addition, the entire device 1, 1 'can also be automatically and reliably cleaned, which is particularly important in the field of pharmacy, cosmetics, chemistry and the food industry because of the sterility.

Reference list

1, 1 '

Device for homogenizing and / or dispersing a flowable material as a whole

2nd

container

3rd

Floor area

4th

Homogenizing and dispersing device overall

5

rotor

6

wave

7

stator

8th

Suction area

9

Pressure range

10th

Product space

11

casing

12th

Passage gap to container 2

13

Deflection device

14

Shut-off device

15

disc

16

Recesses

17, 17 '

Walkways

18th

Outlet

20th

Device for the additional introduction of an additive as a whole

21

Powder suction

22

Intake pipe

23

Leakage gap

30th

Permanent magnets on web 17 '

31

ring

32

Ring 31 permanent magnets

A

Arrow for suction direction

U

Arrow for internal circulation

Claims (9)

Device for homogenizing and / or dispersing a flowable material with a container (2), in the bottom area (3) of which a homogenizing and dispersing device (4) with a rotor / stator arrangement (5, 7) is provided, each of which has passage openings , through which the material sucked in by the rotor (5) is driven outwards and exits into a product space (10) enclosed by a housing (11), a shut-off device (14) in the open position internal mixing or homogenization with recirculation of the material In the container (2) near its bottom and in the closed position, flow mixing and homogenization, if necessary by pumping (external circulation), characterized in that the shut-off device (14) has a disc (15) rotatably mounted on the stator (7). comprises, which has recesses (16) on the outer peripheral edge, which are aligned with peripheral recesses on the stator (7) in the open position and are closed in the closed position by turning the disc (15). Device according to claim 1, characterized in that the shut-off device (14) is arranged in the vicinity of the bottom (3) of the container (2). Device according to claim 1 or 2, characterized in that the recesses (16) of the disk (15) and / or the peripheral recesses on the stator (7) are arranged regularly. Device according to one of claims 1 to 3, characterized in that the rotatable disc (15) has webs (17, 17 ') arranged on the circumference and projecting into the product space (10), through which the shut-off device (14) moves into its open position. and closed position can be brought and is durable in this. Device according to claim 4, characterized in that the webs (17, 17 ') are regularly arranged on the circumference of the rotatable disc (15). Apparatus according to claim 4 or 5, characterized in that the webs are acted upon by the flow of material emerging from the stator (7) for actuating the shut-off device (14). Apparatus according to claim 4 or 5, characterized in that the webs (17 ') have permanent magnets (30) which cooperate with a ring (32) arranged outside the housing (11) with permanent magnets in such a way that opposing permanent magnets (30, 32 ) and thereby give the disc (15) a torque without contact. Device according to one of claims 1 to 7, characterized in that the product stream emerges tangentially to the tank bottom (3) during the internal circulation mixing or homogenization by means of a deflection device (13). Device according to one of the preceding claims, characterized by an opening into the suction area (8) of the homogenizing and dispersing device (4) and the stator (7) penetrating suction pipe (22) for the supply of liquids, powder or the like, which has a defined leakage gap (23) between the pressure (9) and the suction side (8) of the homogenizing and dispersing device (4 ) Has.

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