EP3311921A1 - Agitator ball mill - Google Patents

Abstract

An agitator ball mill has stirring discs (18) which are provided with driving profiles (35) on a stirrer shaft which can be driven in a rotational direction (38). These carrier profiles (35) are formed by channels (36) formed in the respective stirring disc (18), each of which has a wall (39) trailing in the direction of rotation (38) in a straight line radially to the central longitudinal axis (15) Inner channel portion (49) having a length f and then an opposite to the direction of rotation (38) bent outer channel portion (41). The outer channel sections (41) are radially outwardly closed by an outer region (42) of the stirring disc (18) with a radial width e.

Description

The invention relates to a stirred ball mill according to the preamble of claim 1 and a stirring disk for a stirred ball mill according to the preamble of claim 13.

In such from the DE 1 632 424 known agitator ball mill with horizontally arranged grinding container stirring discs with circular driving profiles are known, which may be formed by openings or slots or by shallow grooves. The entrainment profiles are circular and have a radius of 50% to 100% of the disc radius. Beginning at the edge of the window, the profile inflow angle increases by 30% to 50% in the direction of the center of the disk, larger than the angle of attack with a smooth stirrer disk. This is intended to achieve that the dispersing efficiency is significantly increased without destroying grinding media. Due to the large radius of the radius, the correspondingly shaped driving profiles end inside at a considerable radial distance from the stirrer shaft, in each case laterally thereof. At the radially inner end of the driving profiles are substantially tangential to the central longitudinal axis of the agitator shaft, so the rotation vector. Overall, there is no satisfactory entrainment of the grinding media in the inner region of the stirring disk corresponding to a radial extent of about 50% between the inner and peripheral boundary of the stirring disk surface located in the grinding chamber. An equipped with appropriate stirring discs agitator ball mill is suitable only for a comparatively small Mahlkörperfüllgrad of 40 to 60% based on the contents of the grinding chamber. In the area of the stirring disk periphery, the grinding bodies are perpendicular to the trailing walls of the carrier profiles, in each case in the plane of the stirring disks moved radially outward to the agitator shaft. In such a stirred ball mill, only a small power input can be realized, which is also distributed very unevenly in the grinding chamber. This results in a poor space-time yield for the milling process at relatively high, specific energy consumption.

The invention has for its object to provide a higher power input at a lower blade peripheral speed, further to achieve a better energy efficiency for the grinding process to produce a narrow particle size distribution of the treated millbase and at the same time a higher productivity.

The object underlying the invention is achieved in a stirred ball mill with the features of independent claim 1 and by a stirring disc having the features of independent claim 13. The basic solution of the invention is to produce particularly pronounced circular flows in the grinding cells, especially at high Mahlkörper Füllgraden, for more effective entrainment of the grinding this accelerating, already beginning at the agitator shaft, trailing walls of the entrainment profiles in inner region at right angles to the central longitudinal axis and - further outside - form backward curved, and the driving profiles not to the disk periphery, so the outer edge of the stirring disc to continue. Surprisingly, it has been shown that, with boundary conditions comparable to conventional stirred ball mills, a better grinding quality results in the sense of a narrower particle distribution in the treated millbase, when the driving profiles end before reaching the outer edge of the stirring disk. One explanation for this is that the through the driving profiles in the radially outer area accelerated to the outside Mahlkörper be deflected by the upstream in the flow direction of the agitator ball mill upstream stirring disk surface in the upstream grinding cell and by the respective back side stirring surface in the downstream downstream grinding cell. This results in a defined fanning of accelerated by the two sides of a stirring disc outward grinding body, instead of compressing them only as in the prior art in the area between the outer edge of the stirring disk and Mahlraumwand. There are adjacent to the outer edge of the stirring disc, ie no secondary vortex generated in the annular space or gap between the outer edge of the stirring disc and the wall of the grinding container. This results in a significantly improved smoothness of the agitator ball mill associated with a significantly reduced wear of stirring discs and outer Mahlraumwandung. By means of the entrainment profiles of the stirrer disks according to the invention, those parameters can be reliably set and moved, with which a predetermined grinding quality can be achieved with drastically reduced specific energy requirements for the grinding task. The parameters are, in particular, a high level of grinding media with simultaneously lower agitator speed.

The dependent claims 2 to 12 specify advantageous embodiments of the inventive agitator ball mill. The embodiments according to the dependent claims 2 to 6 and 8 to 12 apply mutatis mutandis to the erfindungsgmässe stirrer disk.

Fig. 1

ein Ausführungsbeispiel einer erfindungsgemässen Rührwerkskugelmühle in schematischer Darstellung in einer Seitenansicht in teilweise aufgebrochener Darstellung,

Fig. 2

eine Draufsicht auf ein erstes Ausführungsbeispiel einer erfindungsgemässen Rührscheibe,

Fig. 3

einen Teilquerschnitt durch die Rührscheibe nach Fig. 2,

Fig. 4

eine Teildarstellung aus Fig. 1 in gegenüber Fig. 1 vergrössertem Massstab mit Rührscheiben nach den Fig. 2 und 3,

Fig. 5

ein zweites Ausführungsbeispiel einer erfindungsgemässen Rührscheibe in Draufsicht,

Fig. 6

einen Teilquerschnitt durch die Rührscheibe nach Fig. 5,

Fig. 7

eine Teildarstellung aus Fig. 1 in gegenüber Fig. 1 vergrössertem Massstab mit Rührscheiben nach den Fig. 5 und 6,

Fig. 8

ein drittes Ausführungsbeispiel einer erfindungsgemässen Rührscheibe in Draufsicht,

Fig. 9

einen Teilquerschnitt durch die Rührscheibe nach Fig. 8,

Fig. 10

ein viertes Ausführungsbeispiel einer erfindungsgemässen Rührscheibe in Draufsicht, und

Fig. 11

einen Teilquerschnitt durch die Rührscheibe nach Fig. 10.

Further advantages and details of the invention will become apparent from further subclaims and the following description of embodiments of the invention with reference to the drawing. It shows:

Fig. 1

1 shows an embodiment of an agitator ball mill according to the invention in a schematic representation in a side view in a partially broken-away view,

Fig. 2

a top view of a first embodiment of an inventive stirring disc,

Fig. 3

a partial cross section through the stirring disc after Fig. 2 .

Fig. 4

a partial view Fig. 1 in opposite Fig. 1 enlarged scale with stirring discs after the FIGS. 2 and 3 .

Fig. 5

A second embodiment of an inventive stirring disc in plan view,

Fig. 6

a partial cross section through the stirring disc after Fig. 5 .

Fig. 7

a partial view Fig. 1 in opposite Fig. 1 enlarged scale with stirring discs after the FIGS. 5 and 6 .

Fig. 8

A third embodiment of an inventive stirring disc in plan view,

Fig. 9

a partial cross section through the stirring disc after Fig. 8 .

Fig. 10

A fourth embodiment of an inventive stirring disc in plan view, and

Fig. 11

a partial cross section through the stirring disc after Fig. 10 ,

In FIG. 1 a horizontal agitator ball mill is shown. This has in the usual way a stand 1, which is supported on the bottom 2. In the stator 1 an optionally variable speed drive motor 3 is housed, which is provided with a V-belt pulley 4, from which via V-belt 5 and another V-belt pulley 6, a drive shaft 7 of the agitator ball mill is rotatably driven. The drive shaft 7 is rotatably supported in an upper portion 8 of the stator 1 by means of a plurality of bearings 9.

At the upper portion 8 of the stator 1, a substantially cylindrical grinding container 10 is releasably secured. The cylindrical grinding container 10 has an inner wall 11 and is closed at an end facing the upper section 8 by means of a first cover 12 and at the opposite end by means of a second cover 13. It encloses a grinding chamber 14. The inner wall 11 thus forms the Mahlraum-outer boundary.

Concentric with the common center-longitudinal axis 15 of the grinding container 10 and the drive shaft 7 is a rotationally fixed to the drive shaft 7 connected agitator shaft 16 is arranged in the grinding chamber 14. The grinding chamber 14 is sealed by means of seals 17 between the first cover 12 and the drive shaft 7. The composite of drive shaft 7 and agitator shaft 16 is cantilevered, so no longer stored in the region of the second lid 13. The agitator shaft 16 is provided over its full length in the grinding chamber 14 with stirring tools, which are circular stirring discs 18.

The stirrers 18 are mounted on the agitator shaft 16 and there in a conventional manner, for example by a keyway-groove connection, not shown rotatably held on the agitator shaft 16 and axially held by spacer sleeves 19 at a distance from each other. The agitator shaft 16 with the spacers 19 and the stirring discs 18 form an agitator 20. The spacer sleeves 19 define the substantially annular cylindrical grinding chamber 14 on its inner side, thus forming a Mahlraum-inner boundary.

In the region of the first lid 12, a grinding material feed 21 opens into the grinding chamber 14. From the end of the grinding container 10 opposite the grinding material feed 21, a grinding material discharge 22 issues from the second cover 13.

On the outer circumference of the second cover 13 adjacent last stirring disc 18, a cylindrical cage 23 is formed. He has distributed over its circumference openings 24. In the delimited by the last stirring disc 18 and the cage 23 separating chamber 25, a screen body 26 is arranged, which is attached to the second cover 13 and connected to the grinding stock removal 22. These parts form one of the EP 2 178 642 A1 known Mahlgut-Mahlkörper-separating device 27, enter the regrind (eg grinding suspension) and grinding media 33 through an opening 28.

Adjacent stirring discs 18 each have a same axial distance a to each other. Furthermore, adjacent stirring discs 18 define a separation angle .alpha. Which is defined in each case by a line 29 between the outer edge 30 of a stirring disc 18 and the base of an adjacent stirring disc 18 on the agitator shaft 16, ie at the respective Distance sleeve 19 and formed by a line 15 parallel to the axis 31. The following applies: 30 ° ≤ α ≤ 60 °.

The gap width b of the annular gap 32 between the outer edge 30 and the wall 11 is at most 20% of the free radius R14 of the grinding chamber 14 between its inner boundary and its outer boundary, that is: b ≦ 0.2 · R14.

The grinding chamber 14 is substantially filled with grinding media 33, preferably with grinding media 33 of relatively high density materials, for example ZrO ₂ (zirconia) high performance ceramics having a solids density of 6.0 g / cm ³ . The grinding media degree of filling is in the range of 50% to 90%, in particular in the range of 80% to 90%. The high solids density of the grinding bodies 33 relative to the density of the grinding suspension is important for the desired effects, namely to promote the grinding media 33 even at relatively low agitator speeds in the area of the surfaces of the respective stirring disks 18 in the Mahlkörperverdichtete zone to the outside. Between each adjacent stirring discs 18 are grinding cells 34 (see, eg Fig. 4 ) educated.

The stirring discs 18 are integrated into the respective stirring disc 18, so not over the surface projecting carrier profiles 35 (see, eg Fig. 2 ) are provided for the grinding bodies 33, which begin immediately on the inner wall of the grinding chamber, ie on the spacer sleeves 19. In order for the effects described below to occur to an optimum extent, the width c of the carrier profiles 35 preferably corresponds to 0.5 to 1.5 times the thickness d of the stirring disks 18. Thus, 0.5 · d ≦ c ≦ 1.5 · d. In the embodiment of the FIGS. 2 and 3 These entrainment profiles 35 are formed as flat groove-like channels 36 which are formed on both sides of the corresponding stirring disc 18 overlapping each other, so that between them - like Fig. 3 is removable - a thin wall portion 37 remains. The respective channel 36 has a wall 39, which travels in relation to the direction of rotation 38 of the stirring disk 18 and runs parallel to the central longitudinal axis 15, which is also the center longitudinal axis 15 of the respective stirring disk 18. As Fig. 2 can be removed, this channel 36 at a right angle, radially to the central longitudinal axis 15 outwardly extending inner rectilinear channel section 40, to which radially outwardly opposite to the direction of rotation 38 bent outer channel section 41 connects , which ends at a distance e to the outer edge 30 of the stirring disk 18. The outer channel portion 41 thus terminates at an annular outer region 42 of the stirring disc 18. The distance e or the radial extent e of the enclosing annular outer region 42 is advantageously 0.5 to 1.5 times the thickness d of the stirring discs 18. Thus 0.5 · d ≤ e ≤ 1.5 · d.

As Fig. 2 can still be removed, the grinding media 33 are tangentially entrained in the respective channel 36 of the trailing in the direction of rotation 38 wall 39 and thereby accelerated centrifugally. The tangential velocity and thus the resulting radially outwardly directed centrifugal accelerations increase radially outwardly, as indicated by the radially outwardly increasing length of the velocity arrows 43. Because of the comparatively lower tangential velocity in the vicinity of the stirrer shaft 16 or the spacer sleeve 19, it has proven to be particularly effective in terms of increasing the power input into the grinding chamber 14 when the wall 39 accelerating the grinding bodies 33 to the local peripheral speed is vertical to the rotational vector, ie the central longitudinal axis 15, is oriented. This is effected by the straight, radially disposed inner channel section 40. From the peripheral speed of the grinding bodies 33 results in a corresponding centrifugal acceleration.

According to the invention, the straight, inner channel section 40 has a length f which corresponds to 25% to 60%, preferably 30% to 50%, of the free radius R18 of the stirring disc 18 from the spacer sleeve 19 to the outer edge 30. It is therefore 0.25 · R18 ≤ f ≤ 0.6 · R18 and preferred
0.3 · R18 ≤ f ≤ 0.5 · R18. It has been found that a radial section 40 of the driving profile 35 which goes well beyond 60% of the free radius R18 of the stirring disk 18 leads to unfavorable turbulence of the grinding bodies 33 which is not usable for the grinding process.

By the opposite direction of rotation 38 backward curved formation of the channel portion 41 and in particular its trailing acting as a driving surface wall 39 results in addition to the centrifugal acceleration due to the local peripheral speed tangential radial entrainment of the grinding body 33 located in engagement with the wall 39. These are quasi form-fitting promoted to the outside. The radial entrainment component advantageously increases continuously outwards. In order to achieve an energy-efficient grinding process, it has proved to be particularly advantageous if the radius of curvature r41 is less than 40% of the radius r18 of the stirring disk 18. It should be noted that the channel 36 and in particular the channel portion 41 at the outer end over its full width c expires. The trailing wall 39 passes with a very small transition radius r41 / 42, so to speak, at an acute angle, in the concentric with the outer edge 30 of the stirring disc 18 extending outer boundary of the channel portion 41 through which annular outer region 42 is formed. The transition radius r41 / 42 should advantageously be less than 20% of the width c of the driving profile 35. The following applies: r41 / 42 ≤ 0.2 · c. In the embodiment according to the invention, the trailing wall 39 thus exerts exclusively outward accelerations on the grinding bodies 33 up to its outermost end. This embodiment has proved to be particularly conducive to the formation of undisturbed circular flows, that is, pigtail flows 44 (see, for example, US Pat Fig. 4 ), while avoiding secondary vortexes in the milling cells 34, which in turn is a prerequisite for efficient operation with high media fill levels.

As Fig. 4 can be removed, formed in the individual grinding cells 34 double circular flows, so-called Zopfströmungen 44, from. In this case, the grinding bodies 33 and the grinding stock to be treated, ie the grinding suspension, flow outwards in the direction of the internal wall 11 delimiting the grinding chamber 14 in the region of a stirring disk 18 due to the tangential accelerations caused by the stirring disks 18 and then in the axially middle region the refining cell 34 in accordance with back inside towards the agitator shaft 16 back. The stirring disc 18 acts on both sides radially outside of the groove-like channels 36 formed driving profiles 35 as a kind of deflection device. This outer region 42 of the stirring disc 18, in which this has the same thickness as in the region of the spacer sleeve 19, causes a fanning and change in direction of the accelerated outward mixture of grinding media 33 and ground material. The - related to the total flow direction 45 of the agitator ball mill - upstream side of the outer region 42 of the corresponding stirring disc 18 directs the grinding media-millbase mixture upstream. This action on the grinding bodies 33 opposite to the total throughflow direction 45 causes that these are not transported by the latter in the downstream grinding cell 34 even with increased grinding media filling level and conventional grinding suspension flow rate. This results in a uniform Mahlkörperverteilung throughout the grinding chamber 14. The downstream side of the outer region 42 of the Mahlzelle 34 limiting stirring disc 18, however, causes a corresponding deflection in the downstream direction. The grinding suspension flows through the annular space of the gap 32, which is reduced in terms of the grinding body due to the effect of the inventive design of the stirring discs 18, and is drawn into the circular flow 44 in the downstream grinding cell 34. To support the respective deflections can - like Fig. 4 can be removed - the outer channel sections 41 are provided at the transition to the outer region 42 with a guide bevel 46.

For the description of the embodiment of the Fig. 5 to 7 In the case of identical parts, the same reference numbers and, as far as comparable parts are concerned, the same reference numbers are used with a suffix a, without requiring a new description in detail. The stirring disc 18a after the FIGS. 5 and 6 differs from the stirring disc 18 after the FIGS. 2 and 3 in that the channels 36a are not formed as grooves with a wall section 37 separating them from each other, but that they are designed as through slots having a wall 39 extending from surface to surface of a stirring disc 18a as a driving profile 35a. The mechanism of action basically corresponds to that of the embodiment according to the Fig. 2 to 4 , The considerably reduced by the elimination of the intermediate wall 37 surface of the grinding body 33 accelerating wall 39, leads to a further increase in power consumption of the ball mill or allows a constant power input already at reduced agitator speed. Of course, can be directly transferred from a grinding cell 34 in a downstream adjacent grinding cell 34 through the trained as a continuous slots channels 36a with the corresponding channel sections 40a and 41a. The extent to which this basically undesired effect occurs depends on the selected operating parameters, in particular on the volume throughput per unit time of the grinding suspension and the Mahlkörperfüllgrad. Again, is in Fig. 7 - as well as in Fig. 4 - Recognizable that the grinding media concentration decreases sharply toward the agitator shaft 16 and increases greatly toward the wall 11.

There are mixed configurations between closed groove-like channels and continuous slots formed as slots possible, which lead to further advantages in the sense of the inventive concept.

For the description of the embodiment of the 8 and 9 In the case of identical parts, the same reference numbers and, as far as comparable parts are concerned, the same reference numbers are used with a suffix b, without requiring any further description. When the stirring disc 18b after the 8 and 9 is the two congruent channels 36b separated from each other wall portion 37b approximately over the length of the rectilinear channel portion 40b, while the wall portion 37b in the radially outer, opposite to the direction of rotation 38 curved, groove-like channel portion 41 is still present. This embodiment has the advantage that the entrainment action with respect to the grinding bodies 33 in the region of the lower circumferential speed - ie just where it is particularly required - is intensified by the omission of the separating wall. In the outer grinding media-richer zone in the area of Curved channel section 41, however, prevents the separating wall section 37b an uncontrolled transfer of grinding suspension and grinding media 33 from a grinding cell 34 in an adjacent. This measure serves to narrow the particle size distribution and thus to increase the grinding quality or the grinding efficiency. Otherwise, the previous statements on the mechanism of action also apply here.

Also in the embodiment of the FIGS. 10 and 11 are - as far as identical parts are concerned - the reference numbers from the Fig. 2 to 3 used. As far as similar parts are concerned, the reference numbers from the FIGS. 2 and 3 each subordinate a c. A further detailed description is not required in this respect. When the stirring disc 18c after the 10 and 11 are in the closed wall portions 37c of the groove-like channels 36c respectively immediately adjacent to the agitator shaft 16, so the spacer sleeve 19, regrind passage openings 47 formed by the due to the low concentration of grinding media 33 adjacent to the agitator shaft 16 in Essentially, only ground material passes from a grinding cell 34 into a grinding cell 34 adjacent to an overall throughflow direction 45. For the ratio of the radial extension R47, ie the extension of the grinding material passage openings 47 from the grinding chamber inner boundary in the radial direction of the stirring disc 18c, to the radial extent R18 of the stirring discs 18c of the grinding chamber inner boundary, so the distance sleeves 19th , to the outer edge 30: 0.05 · R18 ≤ R47 ≤ 0.25 · R18. Preferably, R47 ≦ 0.20 * R18, and more preferably: R47 ≦ 0.15 * R18.

The regrind passage openings 47 are arranged only in the immediate vicinity of the spacer sleeve 19 (grinding chamber inner boundary). "In close proximity" means that the radially inner boundary of the regrind passage openings 47 are either adjacent to the spacer sleeve 19 or that the radially inner boundary of the grinding material passage openings are arranged at a small radial distance to the spacer sleeve 19, so that in general that this distance is either zero (adjacent) or up to may be about one tenth of the radial extent R18 of the stirring discs 18c and 18b, respectively (≤ 0.1 * R18).

Because of the present here very low flow resistance in contrast to the conditions in the grinding element-compressed zone in the region adjacent to the outer edge 30 of the stirring discs 18c this embodiment is also suitable for highest Mahlkörper fill levels and particularly high flow rates, while maintaining a uniform grinding media distribution along the grinding chamber 14. A high power input can be effected even at reduced agitator speed. Because of the clearly defined delimitation of the grinding cells 34 against each other, an uncontrolled transfer of grinding suspension from a grinding cell 34 into an adjacent grinding cell 34 is completely prevented. Because of this configuration, particularly high grinding qualities with respect to homogeneity result, which can be detected by a narrow particle size distribution of the treated grinding suspension. Otherwise, the mechanism of action is as described above.

Claims (15)

stirred ball mill with a horizontally arranged grinding container (10), - enclosing a ring-cylindrical, by a grinding container wall (11) and a Mahlraum-inner boundary limited grinding chamber (14) having a free radius R14, - In the one end of a regrind feeder (21) opens and - From which at the other end a regrind discharge (22) with an upstream Mahlgut-Mahlkörper-separating device (27) opens, - With an in the grinding chamber (14) arranged agitator (20), the - In one direction of rotation (38) rotatably driven agitator shaft (16) having a central longitudinal axis (15) and - on the agitator shaft (16) rotatably mounted, an axial distance (a) from each other arranged stirring discs (18, 18a, 18b, 18c), --- wherein the stirring discs (18, 18a, 18b, 18c) have an outer edge (30) and a thickness d, --- wherein the stirring discs (18, 18a, 18b, 18c) have a free radius R18 between the grinding chamber inner boundary and the outer edge (30), --- wherein between the outer edge (30) of the stirring discs (18, 18a, 18b, 18c) and the grinding container wall (11), a gap (32) is formed with a radial width b, --- Wherein each two adjacent stirring discs (18, 18 a, 18 b, 18 c) delimiting a grinding cell (34) and --- Wherein the stirring discs (18, 18a, 18b, 18c) each within the stirring discs (18, 18a, 18b, 18c) formed driving profiles (35, 35a, 35b, 35c) for grinding media (33), each formed by a wall (39), trailing in relation to the direction of rotation (38) and trailing parallel to the central longitudinal axis (15), of channels (36, 36a, 36b, 36c) formed in the agitating disc, each of which relative to the central longitudinal axis (15) are formed - radially outer region by a against the rotational direction (38) bent channel portion (41, 41a, 41b, 41c), characterized,
that the channels (36, 36a, 36b, 36c) each with their in the direction of rotation (38) trailing wall (39) has a radially to the central longitudinal axis (15) rectilinear inner channel portion (40, 40a, 40b, 40c ) with a length f and then the opposite to the direction of rotation (38) bent outer channel section (41, 41a, 41b, 41c), and
in that the outer channel sections (41, 41a, 41b, 41c) are closed radially outwards by an outer region (42) of the stirring disc (18, 18a, 18b, 18c) with a radial width e. Agitator ball mill according to claim 1, characterized in that the stirring disc (18, 18a, 18b, 18c) on both sides of the stirring disc (18, 18a, 18b, 18c) formed channels (36, 36a, 36b, 36c), wherein in each case two the channels (36, 36a, 36b, 36c) formed on different sides of the agitating disc (18, 18a, 18b, 18c) are arranged in pairs congruently. Agitator ball mill according to claim 2, characterized in that the pairs of congruently arranged channels (36, 36 b, 36 c) are formed like a groove and by means of a wall portion (37, 37 b, 37 c) of the stirring disc (18, 18 b, 18 c) are separated from each other. Agitator ball mill according to claim 3, characterized in that the wall section (37b, 37c) in each case in the region of the rectilinear channel section (40b, 40c) by means of a Mahlgut-passage opening (47) is opened, which has a radial extent R47 in the radial direction the stirring disc (18b, 18c). Agitator ball mill according to claim 2, characterized in that the pairwise congruent arranged channels (36a) are connected to each other like a slot. Agitator ball mill according to one of claims 1 to 5, characterized
in that the channels (36, 36a) are provided with guide bevels (46, 46a) at their transition to the outer region (42) of the agitating disc (18, 18a), which deflect the grinding bodies (33) into the refining cell (34) which separates them Channels (36, 36a) are facing. Agitator ball mill according to one of claims 1 to 6, characterized
that the gap (32) applies to the free radius R14 of the grinding chamber (14) when the ratio of the radial width b: b ≤ 0.2 · R14. Agitator ball mill according to one of claims 1 to 7, characterized
that for the ratio of the thickness of the stirring disc d (18, 18a, 18b, 18c) and the radial width e of the outer region (42) of the agitating disc (18, 18a, 18b, 18c) applies: 0.5 x d ≤ e ≤ 1.5 x d , Agitator ball mill according to one of claims 1 to 8, characterized
in that the ratio of the free radius R18 of the stirring disc (18, 18a, 18b, 18c) and the length f of the rectilinear inner channel section (40, 40a, 40b, 40c) is as follows: $$\mathrm{12:25}\cdot \mathrm{R}\mathrm{18}\le \mathrm{f}\le \mathrm{0.6}\cdot \mathrm{R}\mathrm{18}.$$

and preferred $$\mathrm{0.3}\cdot \mathrm{R}\mathrm{18}\le \mathrm{f}\le \mathrm{0.5}\cdot \mathrm{R}\mathrm{18th}$$

Agitator ball mill according to one of claims 1 to 9, characterized
in that the outer channel sections (41, 41a, 41b, 41c) with a radius of curvature r41 / 42 pass into the outer region (42) of the stirring disc (18, 18a, 18b, 18c), in relation to a width c of the channels (36): $$\mathrm{r}\mathrm{41}/\mathrm{42}\le \mathrm{0.2}\cdot \mathrm{c}\mathrm{,}$$

Agitator ball mill according to claim 4, characterized in that the grinding material passage openings (47) are formed only in the immediate vicinity of the grinding chamber inner boundary. Agitator ball mill according to claim 4, characterized in that for the ratio of the radial extent R47 of the respective regrind passage opening (47) to the radial extent R18 of the stirring discs (18, 18a, 18b, 18c), in each case from the grinding chamber inner boundary applies : 0.05 * R18 ≤ R47 ≤ 0.25 * R18, and thereby preferably R47 ≤ 0.20 * R18, and more preferably R47 ≤ 0.15 * R18. Stirrer disk for a stirred ball mill according to one of the preceding claims, which stirrer disc (18, 18a, 18b, 18c) has an outer edge (30) and a thickness d, and which stirrer disc (18, 18a, 18b, 18c) respectively within the stirrer discs (18, 18a, 18b, 18c) formed driving profiles (35, 35a, 35b, 35c) for grinding media (33), each by a - with respect to the direction of rotation (38) of the stirring disc (18, 18a, 18b, 18c) - trailing, parallel to a central longitudinal axis (15) of the stirring disc (18, 18a, 18b, 18c) formed wall (39) formed in the stirring disc (18, 18a, 18b, 18c) channels (36, 36a, 36b, 36c) are formed, each of which - in relation to the central longitudinal axis (15) - in the radially outer region by a against the rotational direction (38) bent channel portion (41, 41a, 41b, 41c) are formed,
characterized,
in that the channels (36, 36a, 36b, 36c), each with its wall (39) trailing in the direction of rotation (38), have an inner channel section (40, 40a, 40b) extending rectilinearly to the central longitudinal axis (15). 40c) and then the opposite to the direction of rotation (38) bent outer channel section (41, 41a, 41b, 41c), and
in that the outer channel sections (36, 36a, 36b, 36c) are closed radially outward by an outer region (42) of the stirring disc (18, 18a, 18b, 18c). Stirrer disc according to claim 13, characterized
in that the stirrer disc (18, 18a, 18b, 18c) has channels (36, 36a, 36b, 36c) formed on both sides of the stirrer disc (18, 18a, 18b, 18c), two of which on each of the two sides of the stirrer disc (18, 18a, 18b, 18c) formed channels (36, 36a, 36b, 36c) are arranged in pairs congruent. Stirrer disc according to claim 13 or 14, characterized in that the channels (36, 36a) are provided at their transition to the outer region (42) with guide bevels (46, 46a).

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