Stirring device

Abstract

A stirring device, in particular an axially conveying stirring device, is proposed for stirring, mixing, homogenizing, dispersing and/or suspending in particular abrasive media, with at least one stirring blade which is configured to rotate about a rotary axis, and with a contour unit which is configured for reducing wear-down of the at least one stirring blade.

Claims

1. An axially conveying stirring device, for stirring, mixing, homogenizing, dispersing and/or suspending, abrasive media, with at least one stirring blade, which is configured to rotate about a rotary axis, and with a contour unit, which is configured for reducing wear-down of the at least one stirring blade and which is embodied at least partly in a one-part-implementation with the at least one stirring blade, wherein the contour unit comprises at least one contour curvature element, which is implemented by a curved portion of the at least one stirring blade, a bending radius of the contour curvature element is smaller with respect to a further bending radius of a stirring blade curvature of a remaining portion of the at least one stirring blade, the at least one contour curvature element is curved in the same direction as the stirring blade curvature of the remaining portion, the contour unit comprises a first bending axis, which encloses a first angle with a stirring blade front edge, the stirring blade curvature of the remaining portion of the at least one stirring blade comprises a second bending axis, which encloses a second angle, which is different from the first angle, with the stirring blade front edge, the contour unit comprises at least one contour edge element, which is implemented at least partly by a stirring blade outer edge of the at least one stirring blade and is embodied, at least in a viewing direction in parallel to the rotary axis, along a circumferential direction at least substantially in a circular-arc shape, with a circular-arc center point being located on the rotary axis the bending radius of the contour curvature element is at least 5% smaller than the bending radius of the remaining portion of the stirring blade, and the bending radius of the contour curvature element corresponds to 10% of a stirring element diameter.

2. The stirring device according to claim 1, wherein the bending radius of the at least one contour curvature element is between 3% and 35% of a stirring element diameter.

3. The stirring device according to claim 1, wherein the at least one contour curvature element is arranged at least substantially on a stirring blade front edge of the at least one stirring blade and/or on a stirring blade outer edge of the at least one stirring blade.

4. The stirring device according to claim 1, wherein the at least one contour curvature element has a bending axis including, in a viewing direction along the rotary axis, an angle between 15 and 75 with the stirring blade front edge of the at least one stirring blade, subsequently to the stirring blade front edge in a rotary direction of the at least one stirring blade.

5. The stirring device according to claim 1, wherein the contour unit comprises at least one blade connection element, which connects the at least one stirring blade to at least one stirring element hub.

6. The stirring device according to claim 5, wherein the at least one blade connection element forms with the rotary axis an angle between 10 and 80.

7. The stirring device according to claim 5, wherein the at least one blade connection element is embodied at least substantially as a rod-shaped bar, a material thickness decreasing towards a stirring blade outer edge of the at least one stirring blade.

8. The stirring device according to claim 5, wherein the at least one blade connection element extends at least substantially in parallel along a stirring blade front edge of the at least one stirring blade.

9. The stirring device according to claim 5, wherein the at least one blade connection element is arranged in such a way that the at least one blade connection element ends flush with the stirring blade front edge of the at least one stirring blade.

10. A stirring element with the at least one stirring device according to claim 1.

11. A system with at least one container and with the at least one stirring device according to claim 1, which is arranged in the at least one container.

12. The stirring device according to claim 1, wherein the curvature of the stirring blade is contiguous.

13. The stirring device according to claim 1, wherein the curved portion of the stirring blade, which implements the curvature element, is contiguously curved.

14. The stirring device according to claim 1, wherein the contour curvature element is located only at a corner of the stirring blade where a front edge of the stirring blade meets an outer edge of the stirring blade.

15. The stirring device according to claim 1, wherein the contour curvature element is located only at a corner of the stirring blade where a front edge of the stirring blade meets an outer edge of the stirring blade.

16. The stirring device according to claim 1, wherein the stirring blade curvature features a bending axis and/or a curve axis which is at least substantially parallel to a stirring blade front edge and/or a stirring blade rear edge.

17. The stirring device according to claim 1, wherein the curvature of the contour curvature element and the stirring blade curvature of the remaining portion of the at least one stirring blade form a smooth, edge-free transition.

Description

DRAWINGS

(1) Further advantages will become apparent from the following description of the drawings. The drawings show an exemplary embodiment of the invention. The drawings, the description and the claims contain a plurality of features in combination. The person having ordinary skill in the art will purposefully also consider the features separately and will find further expedient combinations.

(2) It is shown in:

(3) FIG. 1 a stirring element embodied as an axial agitator with a stirring device, in a perspective view,

(4) FIG. 2 the stirring element in a view from above,

(5) FIG. 3 the stirring element in a lateral view, and

(6) FIG. 4 a system with a container and with a plurality of identical stirring elements of FIGS. 1 to 3.

DESCRIPTION OF THE EXEMPLARY EMBODIMENT

(7) FIGS. 1 to 3 show a stirring element 42, which is embodied as an axial agitator, in a fully assembled state in a perspective view (cf. FIG. 1), in a view from above (cf. FIG. 2) and in a lateral view (cf. FIG. 3). The stirring element 42 comprises in the present case an axially conveying stirring device. The stirring device is intended for stirring, mixing, homogenizing, dispersing and/or suspending abrasive media, in particular fluids and/or solid matters. In the present case the stirring device is made entirely of grade 12 titanium.

(8) The stirring device comprises a stirring element hub 40. The stirring element hub 40 is in the present case embodied in a one-part implementation. As an alternative, it is however also conceivable to implement a stirring element hub in a multi-part implementation. The stirring element hub 40 is configured for accommodating a agitator shaft (not shown) in at least one operative state. The stirring element hub 40 is configured for mounting the stirring device to the agitator shaft axially. An orientation of the agitator shaft defines a rotary axis 12 of the stirring device.

(9) The stirring device moreover comprises four stirring blades 10. For the sake of a better view, only one of the stirring blades 10 is provided with reference numerals in FIGS. 1 to 3. The stirring blades 10 are embodied identically. The stirring blades 10 are fixated to the stirring element hub 40 indirectly. The stirring blades 10 are arranged spaced apart from the stirring element hub 40. The stirring blades 10 are arranged at 90 angular distances from each other. The stirring blades 10 are arranged on the stirring element hub 40 in such a way that the stirring blades 10 include an angle of approximately 45 with the rotary axis 12 (cf. in particular FIG. 3). Alternatively it is also conceivable to fixate the stirring blades to a stirring element hub directly. A stirring device could also comprise three stirring blades, which are in particular arranged at 120 angular distances from each other, and/or two stirring blades, which are in particular arranged at 180 angular distances from each other. In the following only one implementation of one of the stirring blades 10 is described, wherein the description may be applied to the other stirring blades 10, which are in particular embodied identically to each other.

(10) The stirring blade 10 is embodied plate-like. The stirring blade 10 has an at least substantially constant material thickness. Viewed from above, the stirring blade 10 is embodied at least substantially rectangular (cf. in particular FIG. 2). Furthermore the stirring blade 10 comprises, viewed from above, four rounded stirring blade corners. The stirring blade 10 comprises a stirring blade front edge 22, a stirring blade outer edge 24, a stirring blade rear edge 26 and a stirring blade inner edge 28. All edges of the stirring blade front edge 22, the stirring blade outer edge 24, the stirring blade rear edge 26 and the stirring blade inner edge 28 are rounded. The stirring blade 10 also comprises a suction side 46 as well as a pressure side 48, which is situated opposite the suction side 46. Moreover the stirring blade 10 comprises a stirring blade curvature 18. The stirring blade curvature 18 corresponds to a first cambering of the stirring blade 10. A bending radius of the stirring blade curvature 18 corresponds to approximately 36% of a stirring element diameter 20. The stirring element curvature 18 has in the present case a bending axis 50, which is arranged in parallel to the stirring blade front edge 22. The stirring blade curvature 18 is curved towards the pressure side 48. In the present case the stirring blade 10 comprises a concave pressure side 48 and a convex suction side 46.

(11) The stirring blade 10 is configured to rotate about the rotary axis 12 for the purpose of homogenizing and/or dispersing an abrasive medium, in particular a suspension of sulfuric acid and nickelous ore. The stirring blade front edge 22 herein faces toward a rotary direction 52. For the purpose of reducing wear-down of the stirring blade 10 and of lengthening a service life of the stirring element 42, the stirring device herein comprises at least one contour unit 14. In the present case the stirring device comprises four contour units 14, which are embodied identically to each other. Each contour unit 14 is allocated to one of the stirring blades 10. In the following the description is limited to only one of the contour units 14.

(12) The contour unit 14 comprises a contour curvature element 16. The contour curvature element 16 is implemented by a curved portion of the stirring blade 10. The contour curvature element 16 is implemented as a geometric shaping of the stirring blade 10. The contour curvature element 16 is thus embodied in a one-part implementation with the stirring blade 10. The contour curvature element 16 corresponds to a second cambering of the stirring blade 10. The contour curvature element 16 is arranged in an abrasion-prone place. In the present case the contour curvature element 16 is arranged in a proximity of the stirring blade corner in which the stirring blade front edge 22 and the stirring blade outer edge 24 meet. The contour curvature element 16 has a bending radius. The bending radius of the contour curvature element 16 is smaller than the bending radius of the stirring blade curvature 18. The bending radius of the contour curvature element 16 corresponds in the present case to 10% of the stirring element diameter 20. Further the contour curvature element 16 has a bending axis 30, which includes, in a viewing direction along the rotary axis 12, an angle of approximately 30 with the stirring blade front edge 22 of the stirring blade 10. In the present case the contour curvature element 16 is curved in the same direction as the stirring blade curvature 18.

(13) The contour unit 14 moreover comprises a contour edge element 32. The contour edge element 32 is implemented by the stirring blade outer edge 24 of the stirring blade 10. The contour edge element 32 is embodied as a geometric shaping of the stirring blade 10. The contour edge element 32 is thus embodied in a one-part implementation with the stirring blade 10. The contour edge element 32 is arranged in an abrasion-prone place. In the present case the contour edge element 32 is embodied, at least in a viewing direction in parallel to the rotary axis 12, circular-arc-shaped along a circumferential direction 34, with a circular-arc center point 36 that is located on the rotary axis 12. The contour edge element 32 is embodied in such a way that the stirring blade outer edge 24 and/or the stirring element 42 describes a circle in an operative state. Herein the diameter of said circle equals the stirring element diameter 20.

(14) Furthermore the contour unit 14 comprises a blade connection element 38. The blade connection element 38 is configured for connecting the stirring blade 10 to the stirring element hub 40. For this purpose the blade connection element 38 is fixated on the one hand to the stirring element hub 40 and on the other hand to the stirring blade 10. In the present case the blade connection element 38 is embodied in a one-part implementation with the stirring element hub 40. The blade connection element 38 is furthermore embodied in one-part implementation with the stirring blade 10. In the present case the stirring blade 10 is fixated to the blade connection element 38 centrally, in particular at half height of the blade connection element 38. Alternatively, however, any further fixation options are conceivable which are deemed expedient by someone skilled in the art. A blade connection element could also be entirely dispensed with, resulting in particular in a stirring blade being fixated to a stirring element hub directly. The blade connection element 38 is in the present case embodied as a rod-shaped bar. The blade connection element 38 extends in parallel along the stirring blade front edge 22. Herein the blade connection element 38 is arranged in such a way that the blade connection element 38 ends flush with the stirring blade front edge 22. In the present case the blade connection element 38 further includes with the rotary axis 12 an angle of approximately 75 (cf. in particular FIG. 3). The stirring blade 10 includes the same angle with the rotary axis 12. Hence the stirring blade 10 includes an angle of approximately 75 with the rotary axis 12.

(15) Moreover a material thickness of the blade connection element 38 decreases towards the stirring blade outer edge 24. In the present case the blade connection element 38 comprises at least substantially four portions. In a first portion facing the stirring element hub 40 the blade connection element 38 is embodied cylinder-shaped. In the first portion a material thickness of the blade connection element 38 corresponds to a maximum material thickness of the blade connection element 38. The maximum material thickness approximately corresponds to a five-fold material thickness of the stirring blade 10. In a second portion, which in particular directly follows the first partial section, the blade connection element 38 tapers on a first side facing towards the suction side 46. Herein a material thickness of the blade connection element 38 decreases continuously, in particular linearly. At an end of the second portion the blade connection element 38 merges flush into the stirring blade 10. At the end of the second portion the material thickness of the blade connection element 38 approximately corresponds to a three-fold material thickness of the stirring blade 10. In a third portion, which in particular directly follows the second portion, the blade connection element 38 is embodied at least substantially half-cylinder shaped. In the third portion the material thickness of the blade connection element 38 approximately corresponds to a three-fold material thickness of the stirring blade 10. In a fourth portion, which in particular directly follows the third portion, the blade connection element 38 tapers on a second side which faces the pressure side 48. Herein a material thickness of the blade connection element 38 decreases continuously, in particular linearly. At one end of the fourth portion the blade connection element 38 merges flush into the stirring blade 10 on the second side. At the end of the fourth portion the material thickness of the blade connection element 38 corresponds to a minimum material thickness of the blade connection element 38. The minimum material thickness corresponds to the material thickness of the stirring blade 10.

(16) FIG. 4 shows an exemplary system for ore-processing, with a container 44, which is embodied as an autoclave and is arranged horizontally, and with a plurality of stirring elements 42 arranged in the container 44. The container 44 is in the present case divided into three container regions by two fluid-permeable dividing walls 54. The stirring elements 42 are in the present case embodied identically. The stirring elements 42 correspond to the stirring element 42 of FIGS. 1 to 3. Each of the stirring elements 42 hence comprises a stirring device according to the invention. The stirring elements 42 are arranged in the container 44 in such a way that their respective rotary axis 12 is arranged perpendicularly to a horizontally arranged container axis. In the present case the system comprises four stirring elements 42. In a first container region a first stirring element 42 of the four stirring elements 42 is arranged. The first stirring element 42 is arranged on a first agitator shaft. In a second container region a multi-step agitator 56 is arranged. In the present case the multi-step agitator 56 comprises two steps. The multi-step agitator 56 comprises a second stirring element 42 of the four stirring elements 42 and a third stirring element 42 of the four stirring elements 42. The second stirring element 42 and the third stirring element 42 are arranged on second agitator shaft, in particular a common agitator shaft. In a third container region a fourth stirring element 42 of the four stirring elements 42 is arranged. The fourth stirring element 42 is arranged on a third agitator shaft. In an operative state, the abrasive medium (not shown) is arranged in the container 44. The abrasive medium is in the present case embodied as a suspension having a major solid-matter load. Alternatively it is also conceivable to arrange a differing number of stirring elements and/or differently arranged and/or differently implemented stirring elements, which may in particular comprise a stirring device according to the invention, in a container.

REFERENCE NUMERALS

(17) 10 stirring blade 12 rotary axis 14 contour unit 16 contour curvature element 18 stirring blade curvature 20 stirring element diameter 22 stirring blade front edge 24 stirring blade outer edge 26 stirring blade rear edge 28 stirring blade inner edge 30 bending axis 32 contour edge element 34 circumferential direction 36 circular-arc center point 38 blade connection element 40 stirring element hub 42 stirring element 44 container 46 suction side 48 pressure side 50 bending axis 52 rotary direction 54 dividing wall 56 multi-step agitator angle angle angle