Agitator device

Abstract

An agitator device, in particular a draft tube agitator device, with at least one stirring unit, which is rotatable around a rotary axis, which is configured for conveying a fluid in an axial conveying direction and which includes at least one rotor blade element, the projection of said rotor blade element onto a plane that is perpendicular to the rotary axis having an at least substantially circular-arc-shaped outer contour, the rotor blade element comprises at least one first region, which is situated in a blade plane and is at least substantially planar, and includes a second region, which is curved out of the blade plane.

Claims

1. An agitator device with at least one stirring unit, which is rotatable around a rotary axis, is configured for conveying a fluid in an axial conveying direction and comprises at least one rotor blade element, wherein a projection of said rotor blade element onto a plane that is perpendicular to the rotary axis has an at least substantially circular-arc-shaped outer contour, the rotor blade element comprises an inner edge facing toward the rotary axis, wherein the inner edge is embodied at least substantially in a shape of an ellipse arc, and the rotor blade element comprises at least one first region, wherein an outer surface of the first region is situated in a blade plane and is at least substantially planar, and a second region, wherein an outer surface of the second region is curved out of the blade plane.

2. The agitator device according to claim 1, wherein the second region is arranged radially farther outward than the first region.

3. The agitator device according to claim 1, wherein the inner edge faces toward the rotary axis and an outer edge faces away from the rotary axis, wherein the outer edge is longer than the inner edge.

4. The agitator device according to claim 1, wherein at least a large portion of the rotor blade element has an at least substantially constant blade thickness.

5. The agitator device according to claim 4, wherein there is at least one projection of at least a large portion of the rotor blade element onto at least one plane, for which the projected blade thickness is constant.

6. The agitator device according to claim 1, further comprising a sleeve unit, which is configured for a connection to a draft tube, wherein the sleeve unit comprises at least one guide sheet that is arranged in the conveying direction upstream of the stirring unit and defines an inner space wherein, in a mounted state, the stirring unit and at least one first region of the guide sheet are arranged in the inner space.

7. The agitator device according to claim 6, wherein the inner space is at least substantially cylinder-shaped.

8. The agitator device according to claim 6, wherein, in the mounted state, a main extension plane of the guide sheet is arranged at least substantially parallel to the conveying direction.

9. The agitator device according to claim 6, wherein a projection of the guide sheet onto a plane that is perpendicular to the rotary axis follows a curved course.

10. The agitator device according to claim 6, wherein the guide sheet comprises at least one second region, which is in the mounted state arranged upstream of the inner space in the conveying direction and which extends farther than the inner space in a radial direction.

11. The agitator device according to claim 6, wherein the sleeve unit has a radial extension that corresponds to a distance from the rotary axis to a point of the guide sheet that is radially the farthest away from the rotary axis at a frontal end of the sleeve unit with respect to the conveying direction.

12. The agitator device according to claim 11, wherein a radially farthest edge of a projection of the guide sheet onto a plane that is perpendicular to the rotary axis is situated on a smallest circle enclosing a projection of the sleeve unit onto the plane.

13. The agitator device according to claim 12, wherein the radially farthest edge of the guide sheet extends at least substantially parallel to the rotary axis.

14. The agitator device according to claim 6, wherein the sleeve unit has, on the conveying direction front side, an outer contour which is implemented at least substantially in the shape of a truncated-cone envelope.

15. The agitator device according to claim 6, wherein the sleeve unit has an extension along the conveying direction that is at least twice as large as an extension of the stirring unit along the conveying direction.

16. A mixer with at least one agitator device according to claim 6 and with the draft tube that comprises, in a region of the connection with the sleeve unit, an inner cross section corresponding at least substantially to an outer cross section of the sleeve unit in the region of the connection.

17. A method for a production of at least one intermediate and/or end product from at least one initial product, by means of an agitator device according to claim 1, wherein the initial product is stirred by means of the stirring unit.

18. The agitator device according to claim 1, wherein the second region is located radially outside and featuring a curved course with a constant curvature radius.

19. The agitator device according to claim 1, wherein the second region comprises two corners of the rotor blade element which are curved out of the blade plane.

Description

DRAWINGS

(1) Further advantages will become apparent from the following description of the drawings. In the drawings two exemplary embodiments of the invention are shown. The drawings, the description and the claims contain a plurality of features in combination. Someone skilled 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 mixer with an agitator device in a perspective sectional representation,

(4) FIG. 2 an arrangement of guide sheets of a sleeve unit of the agitator device, in a schematic top view,

(5) FIG. 3 a stirring unit of the agitator device, in a perspective view,

(6) FIG. 4 the stirring unit in a schematic top view,

(7) FIG. 5 a rotor blade element of the stirring unit, in a perspective view,

(8) FIG. 6 the rotor blade element, viewed along a direction VI in FIG. 5,

(9) FIG. 7 the rotor blade element, viewed along a direction VII in FIG. 5,

(10) FIG. 8 an exemplary flow chart for a method for a production of a product from an initial product by the agitator device, and

(11) FIG. 9 an alternative mixer with an alternative agitator device in a perspective sectional representation.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

(12) In the exemplary embodiment described below there is more than one item of some of the structural units and/or structural components, For the sake of simplification, analogously implemented structural components and/or structural units provided with the same reference numerals in the drawings will be described only once in the following description of the drawings.

(13) FIG. 1 shows a mixer 54a with an agitator device in a perspective sectional representation. The mixer 54a comprises a draft tube 38a. In the present case, a main extension direction of the draft tube 38a extends in a vertical direction. The agitator device is embodied as a draft tube agitator device. The agitator device comprises a stirring unit 12a, which is embodied to be rotatable around a rotary axis 10a. The stirring unit 12a comprises a centrally arranged hub element 62a. Furthermore the stirring unit 12a comprises, in the present case, three rotor blade elements 18a. However, a different number of rotor blade elements is also conceivable like, for example, two or four or five or six or eight or ten. The stirring unit 12a is configured for conveying a fluid (not shown in FIG. 1) in a conveying direction 16a. In the present case, the conveying direction 16a extends at least substantially parallel to a vertical direction. The conveying direction 16a extends in the present case parallel to the rotary axis 10a. The conveying direction 16a extends in the present case upwards. It is however also conceivable that a conveying direction extends downwards.

(14) In the present case the agitator device comprises a bottom unit 64a. The bottom unit 64a comprises a circumferential flange 68a. The agitator device further comprises a container unit 66a. The container unit 66a comprises a circumferential flange 70a. The container unit 66a is connected to the flange 68a of the bottom unit 64a via the flange 70a of the container unit 66a.

(15) The agitator device comprises a sleeve unit 36a. In the present case the sleeve unit 36a comprises a wall element 76a. Furthermore, the sleeve unit 36a is in the present case connected to the bottom unit 64a. The sleeve unit 36a defines an inner space 42a. In the present case the wall element 76a defines the inner space 42a. Moreover, the inner space 42a is in the present case embodied to be cylinder-shaped. Moreover, the rotary axis 10a implements in the present case a cylinder axis 72a of the inner space 42a. The sleeve unit 36a is configured for a connection to the draft tube 38a. The draft tube 38a has, in a region 56a of the connection with the sleeve unit 36a, an inner cross section 58a which corresponds at least substantially to an outer cross section 60a of the sleeve unit 36a in the region 56a of the connection.

(16) The sleeve unit 36a comprises a guide sheet 40a. A main extension plane of the guide sheet 40a extends in parallel to the conveying direction 16a. The guide sheet 40a comprises a first region 44a, which is arranged within the inner space 42a. A projection of the first region 44a onto a plane that is parallel to the rotary axis 10a has an at least substantially rectangular cross section. The guide sheet 40a comprises a second region 46a, which is arranged upstream of the inner space 42a in the conveying direction 16a. The second region 46a extends farther than the inner space 42a in the radial direction. The guide sheet 40a is connected to the wall element 76a in a form-fit fashion. In the present case the sleeve unit 36a comprises in total five guide sheets 40a, which are embodied at least substantially identically (cf. FIG. 2). In a case when a conveying direction is oriented in an opposite direction, at least one guide sheet may have a curvature that differs from the one described here and/or may be embodied in such a way that it is adapted to a changed flow.

(17) On an in the conveying direction 16a front end 74a, the sleeve unit 36a has a radial extension that corresponds to a distance of a point 48a of the guide sheet 40a, which is radially the farthest away from the rotary axis 10a, from the rotary axis 10a. In the present case the point 48a is located on a radially outer edge 77a of the guide sheet 40a.

(18) On an in the conveying direction 16a front side 50a, the sleeve unit 36a has an outer contour 52a which is implemented at least substantially in the shape of a truncated cone envelope. In the present case an angle between the truncated-cone envelope and a cone axis is approximately 18. Furthermore, the cone axis is in the present case equivalent to the rotary axis 10a. Furthermore the sleeve unit 36a has, along the conveying direction 16a, an extension that is at least twice as great, in the present case approximately seven times as great as an extension of the stirring unit 12a along the conveying direction 16a.

(19) In the present case the stirring unit 12a, the sleeve unit 36a, the bottom unit 64a, the container unit 66a and the draft tube 38a are embodied at least to a large extent of stainless steel.

(20) FIG. 2 shows an arrangement of the guide sheets 40a of the sleeve unit 36a in a schematic top view, viewed towards the rotary axis 10a (cf. FIG. 1). The guide sheets 40a are distributed equally along a circumference of the bottom unit 64a. Viewed towards the rotary axis 10a (cf. FIG. 1), the guide sheets 40a respectively have a first region 78a, located radially inside and featuring a straight course, and have a second region 80a, located radially outside and featuring a curved course. The second region 80a respectively has a constant curvature radius. In the present case all points of the first region 78a are located radially farther inside, with respect to the rotary axis 10a, than an inner wall 81a of the wall element 76a (cf. FIG. 1).

(21) FIG. 3 shows the stirring unit 12a of the agitator device in a perspective view. The rotor blade elements 18a of the stirring unit 12a are in the present case welded to the hub element 62a of the stirring unit 12a. In the present case the stirring unit 12a has a diameter of approximately 500 mm. It is however also conceivable that a stirring unit has a different diameter like, for example, a diameter of approximately 250 mm or a diameter of approximately 1000 mm or a diameter of approximately 1500 mm or a diameter of approximately 2000 mm or a diameter of approximately 3000 mm.

(22) FIG. 4 shows the stirring unit 12a in a schematic top view, viewed along the rotary axis 10a (cf. FIG. 1). Viewed towards the rotary axis 10a (cf. FIG. 1), each rotor blade element 18a respectively has a circular-arc shaped outer contour 20a.

(23) FIG. 5 shows one of the rotor blade elements 18a of the stirring unit 12a in a perspective view. The rotor blade element 18a has a constant blade thickness 32a. In the present case the blade thickness of the rotor blade element 18a is approximately 5 mm. It is however also conceivable that a rotor blade has a different blade thickness like, for example, a blade thickness of approximately 2 mm or a blade thickness of approximately 10 mm or a blade thickness of approximately 20 mm or a blade thickness of approximately 30 mm or a blade thickness of approximately 50 mm or a blade thickness of approximately 70 mm. The rotor blade element 18a comprises a planar first region 24a situated in a blade plane 22a and comprises a second region 26a that is curved out of the blade plane 22a. The first region 24a and the second region 26a together form the rotor blade element 18a. In the present case two corners 82a, 84a of the rotor blade element 18a are curved out of the blade plane 22a. Furthermore, the second region 26a comprises in the present case the two corners 82a, 84a. An imaginary delimitation line 86a between the first region 24a and the second region 26a features a straight course. The first region 24a comprises an ellipse-arc-shaped partial region 88a, which is configured for a form-fit connection to the hub element 62a of the stirring unit 12a. Relative to the rotary axis 10a (cf. FIG. 1), the second region 26a is arranged radially farther outwards than the first region 24a.

(24) The rotor blade element 18a comprises an inner edge 28a that faces towards the rotary axis 10a (cf. FIG. 1) as well as an outer edge 30a that faces away from the rotary axis 10a (cf. FIG. 1) and is longer than the inner edge 28a.

(25) FIG. 6 shows the rotor blade element 18a, viewed along a direction VI of FIG. 5. A projection of the rotor blade element 18a onto a plane that is perpendicular to the direction VI of FIG. 5 features a constant projected blade thickness 34a. In the present case the projected blade thickness 34a corresponds to the blade thickness 32a.

(26) FIG. 7 shows the rotor blade element 18a, viewed along a direction VII of FIG. 5. A projection of the inner edge 28a of the rotor blade element 18a onto a plane that is perpendicular to the direction VII of FIG. 5 has a straight course.

(27) FIG. 8 shows an exemplary flow chart for a method for a production of a product and/or of an intermediate product from at least one initial product, by means of the agitator device. In a first method step 90a the initial product is provided. In a second method step 92a the initial product is stirred by the stirring unit 12a of the agitator device. In a third method step 94a a further processing and/or a finalization of the product and/or the intermediate product are/is carried out. It is conceivable that the method steps 90a, 92a, 94a are passed through iteratively. Furthermore, permanent in-feeding of the initial product and/or permanent conveying away of the intermediate product and/or of the product are/is conceivable.

(28) In FIG. 9 another exemplary embodiment of the invention is shown. The following description and the drawing are substantially limited to the differences between the exemplary embodiments, wherein regarding structural components having the same designation, in particular regarding structural components having the same reference numerals, the drawings and/or the description of the other exemplary embodiment, in particular of FIGS. 1 to 8, may principally also be referred to. To distinguish between the exemplary embodiments, the letter a has been added to the reference numerals of the exemplary embodiment of FIGS. 1 to 8. In the exemplary embodiment of FIG. 9 the letter a has been substituted with the letter b.

(29) FIG. 9 shows an alternative mixer 54b with an alternative agitator device in a perspective sectional view. The agitator device comprises a stirring unit 12b, which is configured for conveying a fluid (not shown) in a vertical conveying direction 16b. The alternative agitator device comprises a sleeve unit 36b. The sleeve unit 36b defines an inner space 42b. The sleeve unit 36b comprises rear guide sheets 96b, which are arranged downstream of the stirring unit 12b in the conveying direction 16b. The guide sheets 96b are arranged in the inner space 42b.

REFERENCE NUMERALS

(30) 10 rotary axis 12 stirring unit 16 conveying direction 18 rotor blade element 20 outer contour 22 blade plane 24 first region 26 second region 28 inner edge 30 outer edge 32 blade thickness 34 projected blade thickness 36 sleeve unit 38 draft tube 40 guide sheet 42 inner space 44 first region 46 second region 48 point 50 side 52 contour 54 mixer 56 region 58 cross section 60 cross section 62 hub element 64 bottom unit 66 container unit 68 flange 70 flange 72 cylinder axis 74 front end 76 wall element 77 edge 78 first region 80 second region 81 wall 82 corner 84 corner 86 delimitation line 88 partial region 90 method step 92 method step 94 method step 96 guide sheet