Mixing device with integrated delivery pump

Abstract

The invention relates to a mixing device (1) for intermixing powder particles and/or granular particles, or a similar free-flowing solid with at least one liquid. The mixing device comprises a feed duct (5) for a solid, an inlet (17) for the liquid, at least one mixing implement (8) that is rotatable about an axis in a mixing chamber (7), and an outlet for the mixture. The device is characterised by a delivery pump (14) which is arranged between the inlet (17) and the mixing implement (8).

Claims

1. A mixing device (1) for intermixing powder particles and/or granular particles or a similar free-flowing solid with at least one liquid, the mixing device comprising: a feed duct (5) for the solid; an inlet (17) for the liquid; a mixing chamber (7), wherein the feed duct (5) leads directly into the mixing chamber (7); at least one mixing implement (8) rotatable about an axis in the mixing chamber (7), wherein the mixing implement (8) is formed by a rotor (9) and a stator (10), the stator (10) surrounding the feed duct (5) in the mixing chamber (7) to bound an inner volume in the mixing chamber (7), the rotor (9) including an upstanding rotor rim (11) positioned radially outwardly from the stator (10) away from the axis, wherein the solid is discharged from the feed duct (5) into the inner volume; an outlet (6) for a mixture of the solid and the liquid, wherein the outlet (6) is in direct communication with the mixing chamber (7); and a delivery pump (14) arranged between the inlet (17) and the mixing implement (8), wherein the liquid is delivered from the inlet (17) into the inner volume by the delivery pump (14), wherein the solid and the liquid in the inner volume are mixed by the mixing implement (8) with the rotor (9) rotating relative to the stator (10).

2. The mixing device according to claim 1, wherein the outlet (6) is arranged horizontally and the feed duct (5) is arranged vertically.

3. The mixing device (1) according to claim 1, wherein the delivery pump (14) is arranged above the inlet (17) with respect to the delivery direction of the solid.

4. The mixing device (1) according to claim 1, wherein the feed duct (5) is arranged eccentrically with respect to the axis of rotation of the mixing implement (8).

5. The mixing device according to claim 1, wherein the feed duct (5) is selectively closable by means of a seal or a plug or a pressure piston (26), wherein the seal or the plug or the pressure piston (26) is movable in the feed duct (5) along the feed direction of the solid and is flush with the walls of the feed duct (5).

6. The mixing device (1) according to claim 1, wherein a further connection (22) exists between the delivery pump (14) and the mixing chamber (7).

7. The mixing device according to claim 6, wherein the further connection (22) is arranged inside a housing (23) of the mixing device (1).

8. The mixing device (1) according to claim 1, wherein the delivery pump (14) is formed by a centrifugal pump comprising a delivery wheel (15) comprising a plurality of conveying vanes (16).

9. The mixing device (1) according to claim 1, wherein the rotor (9) is arranged between the stator (10) and the delivery pump (14).

10. The mixing device (1) according to claim 1, wherein the delivery pump (14) is arranged on the same drive shaft (12) as the mixing implement (8).

11. The mixing device (1) according to claim 1, wherein the outlet (6) empties into an outline line, which leads back into a container for the liquid, which is connected to the inlet (17) via a feed line.

12. The mixing device (1) according to claim 1, wherein the mixing device is embodied in a modular manner, with a mixing module (2) comprising the mixing implement (8), a delivery module (3) comprising the delivery pump (14), and an inlet module (4) comprising the inlet (17), wherein the delivery module can be arranged between the mixing module and the inlet module.

13. The mixing device (1) according to claim 7, wherein the further connection (22) is a connecting channel embodied in the housing (23).

14. The mixing device (1) according to claim 6, wherein the further connection (22) is formed by at least one bore.

15. The mixing device (1) according to claim 6, wherein the further connection (22) is formed by at least one nozzle.

16. The mixing device (1) according to claim 8, wherein the plurality of conveying vanes (16) includes four conveying vanes.

17. The mixing device (1) according to claim 8, wherein the plurality of conveying vanes (16) includes eight conveying vanes.

18. The mixing device (1) according to claim 8, wherein the conveying vanes (16) are curved.

19. The mixing device (1) according to claim 8, wherein the conveying vanes (16) are arranged on the side of the delivery pump (14) facing away from the mixing implement (8).

20. The mixing device (1) according to claim 6, wherein the further connection (22) is formed by a pipe or a hose line on the outside of a housing (23) of the mixing device (1), and has an opening (24) into the mixing chamber (7).

21. The mixing device (1) according to claim 20, wherein the opening (24) of the further connection (22) is formed by an annular gap (25).

22. The mixing device (1) according to claim 21, wherein the annular gap (25) is arranged above the mixing chamber (7) with respect to the delivery direction of the liquid and around the feed duct (5).

23. The mixing device (1) according to claim 1, wherein a radial gap is defined between the stator (10) and the rotor rim (11), wherein first portions of the rotor (9) are axially spaced from the stator (10), in a direction parallel to the axis, to define an axial spacing between the first portions of the rotor (9) and the stator (10), and, wherein the radial gap is in communication with the axial spacing.

24. The mixing device (1) according to claim 1, wherein the inlet (17) is arranged horizontally and the feed duct (5) is arranged vertically.

Description

(1) Exemplary embodiments of the invention will be described in more detail below by means of the drawings. In partly schematized illustration:

(2) FIG. 1 shows a mixing device according to an embodiment of the invention in cross section;

(3) FIG. 2 shows the mixing device from FIG. 1 without delivery module;

(4) FIG. 3 shows a perspective view of the delivery wheel of the mixing device from FIG. 1;

(5) FIG. 4 shows a top view onto the delivery wheel from FIG. 3;

(6) FIG. 5 shows a mixing device according to a further embodiment of the invention in cross section;

(7) FIG. 6 shows a mixing device according to a further embodiment of the invention comprising a bypass line in cross section;

(8) FIG. 7 shows a mixing device according to an embodiment of the invention comprising an eccentric feed duct in cross section;

(9) FIG. 8 shows a mixing device according to a further embodiment of the invention comprising an internal bypass line in cross section; and

(10) FIG. 9 shows a mixing device according to a further embodiment of the invention in cross section.

(11) FIG. 1 shows a mixing device 1 according to one embodiment of the invention. The mixing device is of modular construction and comprises a mixing module 2, a delivery module 3 and an inlet module 4. The modules 2, 3 and 4 are connected to one another, but can be detached from one another and can be connected to one another in a different way. FIG. 2 shows an alternative, in the case of which provision is not made for a delivery module 3 and the mixing module 2 is directly connected to the inlet module 4.

(12) The mixing module 2 has a vertical central feed duct 5 for feeding a solid as well as a horizontal lateral outlet 6 for the mixture. The feed duct 5 and the outlet 6 empty into a mixing chamber 7, in which a mixing implement 8 is arranged, which is formed by a rotor-stator device 9, 10 comprising a rotor rim 11 and a stator rim. The rotor 9 is connected to a rotating drive shaft 12, which is driven by means of a motor 13.

(13) In the delivery module 3, which is connected to the mixing module 2, provision is made for a delivery pump 14, which is embodied as centrifugal pump, comprising a delivery wheel 15 and a plurality of conveying vanes 16, which are arranged on the delivery wheel 15. The conveying vanes 16 are arranged on the side of the delivery wheel 15, which faces away from the mixing module 2. The delivery wheel 15 as well as the rotor is connected to the drive shaft 12 and is rotated by rotation of the drive shaft 12.

(14) The inlet module 4 is connected on the end of the delivery module 3, which is shown on the bottom in image orientation. The inlet module 4 comprises a horizontal lateral inlet 17 for the liquid.

(15) The inlet 17 is connected to a liquid container, which is not shown. The outlet 6 can also be connected to the liquid container, so that a closed circuit is formed and the mixture can be delivered back into the liquid container and can be fed to the mixing process again.

(16) During operation, i.e. in response to the rotation of the rotor 9 and of the delivery wheel 15, the solid is sucked into the mixing chamber 7 through the feed duct 5. Due to the particle acceleration by means of the rotor 9, an underpressure is in particular created in the mixing chamber 7, which has the effect that powders or granules are sucked through the feed duct 5. The rotor 9 is embodied and arranged in such a way that the solid is initially delivered separately from the liquid and encounters the liquid only in a predetermined area with a high turbulence. The solid is thereby accelerated within the rotor 9 and is finely distributed prior to the dispersion into the liquid due to the volume increase towards the edge area of the rotor 9. The finely distributed solid particles then encounter a liquid jacket comprising a relatively large surface, so that they are dispersed into the liquid in an agglomerate-free manner.

(17) The delivery pump 14 creates an additional suction effect, so that it is ensured that sufficient liquid and solid reach into the mixing chamber 7, even if the liquid has a high viscosity or if the viscosity thereof increases during the mixing process.

(18) FIGS. 3 and 4 show the delivery wheel 15 according to the embodiment of the invention illustrated in FIG. 1. The delivery wheel 15 has eight conveying vanes 16, each of which have a curvature and extend from the radially outer edge of the delivery wheel in the direction of a hub 18, wherein the radially inner end of the conveying vanes 16 is spaced apart from the hub 18.

(19) FIG. 5 shows a mixing device 1 according to a further embodiment of the invention at hand. The embodiment in FIG. 5 differs from the embodiment in FIG. 1 in that the delivery pump 14 is formed by a rotor/stator device comprising a rotor 19 and a stator 20. The rotor 19 comprises at least one rotor rim 21. A particularly fine dispersion is attained by means of this embodiment. This is in particular the case, when the mixture recirculates, i.e. is fed to the mixing process again.

(20) FIG. 6 shows an embodiment of the invention comprising a further connection 22 between the delivery module 3 and the mixing chamber 7. The further connection runs outside of a housing 23 on the outside thereof, from a horizontally external side of the delivery module 3 to an outside of the mixing module 2. The further connection 22 forms a bypass line for the liquid delivered by the delivery pump 14. The terms further connection and bypass line will be used synonymously hereinafter. A portion of the delivered liquid can bypass the delivery duct along the axis of the delivery pump 14 between the delivery module 3 and the mixing module 2 via the further connection 22 and can reach directly back into the mixing module 2. The further connection 22 is formed by a hose or pipe line. The further connection 22 has an opening 24, which leads into the mixing chamber 7. The opening 24 is located on the side located opposite the mixing implement 8in the illustrated orientation on the upper sideof the mixing chamber 7, so that the liquid can run into the mixing chamber 7 with the aid of gravity. The opening 24 is formed by means of an annular gap 25. The annular gap 25 surrounds the feed duct 5 concentrically. In this embodiment, the feed duct 5 is aligned with the axis of the mixing implement 8.

(21) FIG. 7 shows an embodiment of the invention comprising an eccentric feed duct 5 and an exterior bypass line 22. The feed duct 5 is arranged so as to be displaced with respect to the axis of the mixing implement 8. The opening 24 of the bypass line 22, which is embodied as annular gap 25, is expanded inside the housing 23 of the mixing device 1 in such a way that the annular gap 25 also runs concentrically around the feed duct 5.

(22) FIG. 8 shows an embodiment of the invention, wherein the further connection 22, which forms the bypass line, inside the housing 23 of the mixing device 1 runs along the delivery direction of the liquidascending in the illustrated orientationfrom the delivery module 3 to the mixing module 2. The opening 24 is also located completely in the interior of the housing 23 of the mixing device 1. The bypass line 22 is completely integrated into the housing 23 of the mixing device 1 and forms a channel, which is completely surrounded by the housing 23.

(23) FIG. 9 shows an embodiment comprising an eccentric feed duct 5. The feed duct 5 is closed by means of a piston 26. The piston 26 is arranged so as to be capable of being displaced along the feed direction of the solid in the feed duct 5. The piston 26 is flush with the walls of the feed duct 5 and forms a closed hollow space with the housing 23 and the mixing chamber 7. By means of a corresponding integration of the piston 26, the seal of the mixing chamber 7 is embodied in a pressure-resistant manner. Solid to be fed is guided into the mixing chamber 7 by moving the piston 26 along the feed duct 5.

LIST OF REFERENCE NUMERALS

(24) 1 mixing device 2 mixing module 3 delivery module 4 inlet module 5 feed duct 6 outlet 7 mixing chamber 8 mixing implement 9 rotor 10 stator 11 rotor rim 12 drive shaft 13 motor 14 delivery pump 15 delivery wheel 16 conveying vane 17 inlet 18 hub 19 rotor 20 stator 21 rotor rim 22 further connection (bypass line) 23 housing of the mixing device 24 opening 25 annular gap 26 piston