EP1724022B1 - Stirring mill - Google Patents

Abstract

The radial gap width (g) of the outer grinding chamber (8a) is less than the gap width (h) of the inner grinding chamber (8b). The cross sectional surface area (Fa) of the outer grinding chamber is no greater than that (Fb) of the inner grinding chamber. Preferably Fb lies between 1.2 times Fa and 7 times Fa. The gap width of the outer grinding chamber is related to the diameter (i) of the largest grinding aid solids (38), which is preferably up to 1.5 mm. The gap width of the outer grinding chamber is preferably up to 5.0 mm.

Description

The invention relates to a stirred mill according to the preamble of claim 1.

In such an agitating mill known from EP 0 824 964 B1 (corresponding to US Pat. No. 5,950,943), both the inner grinding chamber and the outer grinding chamber are smooth-walled without perforations and are free of stirring tools. The gap width, ie the radial extent of the outer grinding chamber is significantly greater than that of the inner grinding chamber. This is intended to achieve that the grinding and dispersion of the flowable, slurried grind takes place predominantly by shear effects in such a way that the local stress intensity of the grind over the entire Mahlweg is substantially constant. Due to the smooth-walled configuration of the cylindrical boundary walls of the outer grinding chamber and the inner grinding chamber, a flow is generated in which the auxiliary grinding bodies are moved in layers relative to one another. The shear gradient and thus the local stress intensity is constant in the outer grinding chamber on the one hand and in the inner grinding chamber on the other hand above the respective Mahlraumhöhe. Since the gap width of the inner grinding chamber is smaller than the gap width of the outer grinding chamber, the shear gradient in the outer grinding chamber and in the inner grinding chamber can be made the same size; it is then constant over virtually the entire grinding space. It has turned out to be problematical that, with a high grinding auxiliary body filling level, it is difficult to start up the agitator mill. Because of the problems with starting up the agitator mill, it is operated with a reduced grinding aid filling, which in turn leads to an unfavorably wide grinding stock particle size distribution. Because of this reduction of Mahlhilfskörper the amount of through the Mahlhilfskörper-return channels is reduced back, the risk increases that a so-called Mahlgut-shot takes place, ie the Mahlgut feed chamber supplied to be ground or dispersing regrind can flow in the short circuit through the Mahlhilfskörper-return channels in the direction of the separator.

The invention has for its object to design a stirred mill of the generic type so that the startup of the stirred mill easier and during operation a narrow grinding material particle size distribution is achieved.

This object is achieved by the features in the characterizing part of claim 1. As a result of the measures according to the invention, when the agitator mill is switched off, in particular in the internal grinding space, there is no wedging of the downwardly settling grinding auxiliary bodies with the adjacent walls. When starting the agitator mill Mahlhilfskörper can therefore be very easily set in motion again. The inventive measures is further achieved that a jam Mahlhilfskörper does not occur in the outer grinding chamber in front of the inner grinding chamber, since the gap width of the inner grinding chamber is greater than that of the outer grinding chamber. In the outer grinding chamber, a shear grinding takes place. Since the Mahlhilfskörper strive to escape an increased shear, they flow through the expanding to the inner grinding chamber deflection into the inner grinding chamber. Due to the described effects, the agitator mill can be operated with a high Mahlhilfskörper filling level, ie the Mahlhilfskörper filling need not be reduced. This in turn leads to a particularly intensive grinding while avoiding a grinding stock pass, since Mahlhilfskörper be transported back in sufficient amount by the Mahlhilfskörper-return channels.

The inventively desired effects are still particularly favorably influenced by the development according to claim 2, wherein the development according to claim 3 continues to be supportive.

This effect of loosening the ground material in the internal grinding chamber and thus facilitating the flow of Mahlgut Mahlhilfskörper mixture is supported by the mounted at least on the inner stator according to claim 4 surveys, which may be formed according to claim 5 as tools. By at least the inner stator mounted elevations or tools takes place an intensive turbulence of Mahlhilfskörper and thus again an intensive use of the ground material. This intensive turbulence also counteracts the formation of a stationary boundary layer on the grinding chamber boundary walls, so that improved cooling of the ground material takes place.

Through the development according to claims 6 and 7 it is prevented that deposit on the inner wall of the rotor Mahlhilfskörper; due to the helical arrangement of the tools on the outer jacket of the inner stator, the inner wall of the rotor is completely swept over and thus kept free of such deposits.

By the development according to claim 8 can be achieved that a certain backpressure effect is exerted on the internal grinding chamber, so that the dispersing and the grinding intensity is increased. This effect can be achieved in particular by a development according to claim 9. By such a congestion device, a local increase in Mahlhilfskörper concentration be achieved in the upper end of the inner grinding chamber, which in turn leads to a particularly intensive grinding or dispersion and thereby to a very narrow Mahlgut particle size distribution. Such a separately installed storage device can be adapted according to claim 10 as a separate component of each specific application. In this case, the gap width of the outflow channel can be constant in the direction of the separating device, or else increase in accordance with claim 11.

In principle, it is particularly advantageous if the inner stator is provided in the region of the outflow channel according to claim 12 with a wear protection, which is particularly advantageous if the gap width of the outflow channel to the separating device, ie radially inwardly, not enlarged, so if the flow area is reduced with a corresponding acceleration of the Mahlgut Mahlhilfskörper flow.

The development according to claim 13 and in particular claim 14, it is possible to adjust the size of Mahlhilfskörper-return channels also in a simple way the grinding or dispersing goals. By forming these return channels in a Mahlhilfskörper-return module they can be incorporated from one side into the module, which is particularly easy to manufacture. This configuration also makes it possible to give the Mahlhilfskörper-return channels with simple manufacturing measures any desired contours. This simple production also makes it possible to optimize the flow cross sections of the grinding aid body return channels in their course from the inside to the outside, whereby claim 15 specifies optimal ranges for the ratio of the widths of the inlet openings and outlet openings to one another.

The fact that the height of the Mahlhilfskörper-return channels in the direction of the central longitudinal axis can be made relatively small, the risk of a passage through the Mahlhilfskörper can continue to be reduced without a good separation of Mahlhilfskörper is affected by the ground material. Claim 16 specifies optimum boundary conditions for this purpose. Such optimal conditions are further improved by the embodiment according to claims 17 and 18.

Fig. 1

eine schematische Darstellung einer Rührwerksmühle in einer Seitenansicht,

Fig. 2

einen Längsschnitt durch ein erstes Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 3

einen Querschnitt durch den Mahlbehälter gemäß der Schnittlinie III-III in Fig. 2,

Fig. 4

eine Seiten-Längs-Ansicht eines Innen-Stators der Rührwerksmühle,

Fig. 5

eine perspektivische Ansicht eines Mahlhilfskörper-Rückführ-Moduls der Rührwerksmühle nach den Fig. 2 bis 4,

Fig. 6

einen Längsschnitt durch ein zweites Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 7

eine perspektivische Ansicht des Mahlhilfskörper-Rückführ-Moduls der Rührwerksmühle nach Fig. 6,

Fig. 8

einen Längsschnitt durch ein drittes Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 9

einen Längsschnitt durch ein viertes Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 10

einen Längsschnitt durch ein fünftes Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 11

einen Längsschnitt durch ein sechstes Ausführungsbeispiel eines Mahlbehälters der Rührwerksmühle,

Fig. 12

eine Seitenansicht eines Mahlhilfskörper-Rückführ-Moduls der Rührwerksmühle nach Fig. 11, und

Fig. 13

eine Ansicht des Mahlhilfskörper-Rückführ-Moduls nach Fig. 12 von unten.

Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the drawing. It shows

Fig. 1

a schematic representation of a stirred mill in a side view,

Fig. 2

a longitudinal section through a first embodiment of a grinding container of the agitator mill,

Fig. 3

a cross section through the grinding container according to the section line III-III in Fig. 2,

Fig. 4

a side longitudinal view of an internal stator of the agitator mill,

Fig. 5

3 is a perspective view of a grinding aid return module of the agitator mill according to FIGS. 2 to 4,

Fig. 6

a longitudinal section through a second embodiment of a grinding container of the agitator mill,

Fig. 7

6 is a perspective view of the grinding aid return module of the agitator mill of FIG. 6, FIG.

Fig. 8

a longitudinal section through a third embodiment of a grinding container of the agitator mill,

Fig. 9

a longitudinal section through a fourth embodiment of a grinding container of the agitator mill,

Fig. 10

a longitudinal section through a fifth embodiment of a grinding container of the agitator mill,

Fig. 11

a longitudinal section through a sixth embodiment of a grinding container of the agitator mill,

Fig. 12

a side view of Mahlhilfskörper-return module of the agitator mill of FIG. 11, and

Fig. 13

a view of the Mahlhilfskörper feedback module of FIG. 12 from below.

The agitator mill shown in Fig. 1 has in the usual way a stand 1, to which a cylindrical grinding container 2 can be attached. In the stator 1, an electric drive motor 3 is housed, which is provided with a V-belt pulley 4, of which via V-belt 5 with a drive shaft 6 rotatably connected V-belt pulley 7 is rotationally driven.

As is apparent in particular from FIGS. 2 and 3, the grinding container 2 consists of a cylindrical inner wall 9 surrounding a grinding chamber 8, which is surrounded by a substantially cylindrical outer jacket 10. The lower wall of the grinding chamber 8 is formed by an annular bottom plate 12, which is fastened to the grinding container 2 by means of screws 13.

The grinding container 2 has an upper annular flange 14, by means of which it is attached to the underside of a support housing 15 by means of screws 16 which is mounted on the stator 1 of the agitator mill. The grinding chamber 8 is closed by means of a lid 17. The support housing 15 has a central bearing and seal housing 18 which is arranged coaxially to the central longitudinal axis 19 of the grinding container 2. This bearing and seal housing 18 is penetrated by the likewise coaxial to the axis 19 extending drive shaft 6, to which a stirrer 20 is mounted. In the grinding chamber 8 adjacent region of the bearing and seal housing 18 opens a regrind supply line 21 a.

On the annular bottom plate 12 a projecting into the grinding chamber 8, approximately cup-shaped, cylindrical inner stator 22 is attached, consisting of a grinding chamber 8 bounding, coaxial to the axis 19, cylindrical outer shell 23 and a likewise coaxial to the axis 19, cylindrical inner shell 24 exists. They limit between a cooling space 25. The cooling space 25 is connected to a cooling space 26 in the bottom plate 12, the cooling water via a cooling water supply port 27 is supplied, which is discharged via a cooling water discharge port 28. The cooling space 11 of the grinding container 2 is supplied with cooling water via a cooling water supply pipe 29, which is discharged via a cooling water discharge pipe 30.

At the upper, located above the grinding chamber 8 annular end portion 31 of the inner stator 22, a Mahlgut Mahlhilfskörper-separating device 32 is arranged, which is connected to a regrind discharge line 33. Between the separator 32 and the drain line 33, a grinding stock hopper 34 is provided. The drain line 33 is provided in the region of the bottom plate 12 with a mounting bracket 35, which is releasably connected by means of screws 36 with the bottom plate 12 and the fixedly connected to this inner stator 22. The separating device 32 is sealed relative to the annular end portion 31 of the inner stator 22 by means of a seal 37 and can be pulled out after loosening the screws 36 together with the drain line 33 and the collecting hopper 34 from the inner stator 22 down. The separating device 32 can thus be pulled out of the grinding chamber 8, without the Mahlhilfskörper located in this 38 must be removed from the grinding chamber 8, since the filling of the grinding chamber 8 with these Mahlhilfskörpern 38 with non-driven agitator 20 does not reach to the front part 31.

The agitator 20 is cup-shaped in its basic structure, ie it has a substantially annular cylindrical rotor 39. The rotor 39 has a cylindrical inner wall 41, which has a cylindrical outer wall 40 and a coaxial with it and coaxial with the axis 19. The outer wall 40 and the inner wall 41 are smooth-walled and as closed surfaces trained, so have no openings. Between the outer wall 40 and the inner wall 41 of the rotor 39, a cooling space 42 is formed.

At its upper end, the agitator 20 is provided with a cover-like termination part 43, to whose bottom side facing the rotor 39, a closure plate 44 is attached. The termination part 43 and the end plate 44 are attached to the drive shaft 6.

Between the rotor 39 and the end plate 44 of the agitator 20, a Mahlhilfskörper-return module 45 is arranged. The rotor 39, the return module 45 and the end plate 44 are detachably connected together by tie rods 46. The supply and removal of cooling water to the cooling chamber 42 via formed in the shaft 6 and in the return module 45 cooling water channels 47, 48th

Due to the smooth-walled configuration of the inner wall 9 of the grinding container 2, which thus has no tools, and the likewise smooth-walled configuration of the outer wall 40 of the rotor 39, an outer grinding chamber 8a is formed. By the likewise tool-free smooth-walled configuration of the inner wall 41 of the rotor 39 and the outer jacket 23 of the inner stator 22, an inner grinding chamber 8b is limited. In this inner grinding chamber 8b protrude on the outer surface 23 of the inner stator 22 mounted, designed as a pin-shaped tools 49 surveys in which - as is apparent in particular from Fig. 4 - are arranged helically over the circumference and the length of the outer shell 23. As can be seen in particular from FIG. 4, adjacent tools 49 in the circumferential direction of the inner stator 22 overlap one another in the direction of the central longitudinal axis 19 arranged so that in one revolution of the rotor 39 whose inner wall 41 is completely swept by the tools 49.

As can be seen from the above, the grinding chamber 8 is thus divided into a cylindrical outer grinding chamber 8a on the one hand and a cylindrical annular grinding chamber 8b on the other hand, connected by a constantly widening from outside to inside deflection space 50 in the vicinity of the bottom plate 12 are.

As is apparent from Figs. 2 and 4, the cylindrical separator 32 consists of a stack of annular disks 51, between each of which a separating gap 52 is left free, the width of which is generally smaller than the diameter of the smallest grinding auxiliary body 38 used; However, the width can also be greater, since the separation of the Mahlhilfskörper 38 takes place before reaching the separator 32. The stack of annular discs 51 is the end side, ie at the end plate 44 facing side, completed by a closure plate 53. The separator 32 is disposed within the return module 45.

• d > c und bevorzugt
• d ≥ 1,5 c.

As is apparent from FIGS. 2 and 5, grinding aid body return channels 54 are formed in the grinding aid body return module 45. Their respective inlet opening 55 is located immediately adjacent to the separating device 32. Their respective outlet opening 56 opens into a ring-cylindrical grinding material feed area 57, which is formed between the return module 45 and the inner wall 9 of the grinding container 2. The return channels 54 have their smallest width c at the inlet opening 55 and their largest width d at the outlet opening 56, wherein the widths c and d are respectively measured in the circumferential direction. The return channels 54 are opposite to the direction of rotation 58 from the inlet 55 to the outlet 56 of the agitator 20, seen from the inside out, convexly curved. For the width c applies in relation to the width d:

• d> c and preferred
• d ≥ 1.5 c.

In the embodiment of FIGS. 2 to 5, the return channels 54 extend in the direction of the axis 19 almost over the full height of the return module 45, wherein its axial height e is greater than the axial height f of the separator 32. Die Return channels 54 extend in this embodiment except via the separator 32 in the direction of the axis 19 still obliquely upward from the upper end of the inner grinding chamber 8b and inside to the separator 32 leading, so tapering in the direction of the end plate 44 towards frustoconical Outflow channel 59. In this embodiment, the return channels 54 are also open to the outflow channel 59, as Fig. 2 reveals. The outflow channel 59 is therefore not spatially limited upwards. Rather, it is open in the direction of the central longitudinal axis 19 towards the internal grinding chamber 8b and thus permeable to the exit of the grinding auxiliary bodies 38, while the millbase flows through the outflow channel 59 in the direction of the separating device 32.

The material to be ground flows through the grinding chamber 8 corresponding to the flow direction arrows 60 coming from the grinding material supply line 21 through a Mahlgut feed chamber 61 between the end portion 43 of the agitator 20 on the one hand and the lid 17 and the adjacent region of the inner wall 9 on the other hand, the grinding material feed Area 57, the outer grinding chamber 8a down, by the steadily widening deflection space 50 radially inwardly and from there through the inner grinding chamber 8b after on the way up to the outflow channel 59 and from there to the separator 32. On the way through the outer grinding chamber 8a, the deflection space 50 and the inner grinding chamber 8b, the material to be ground is milled in rotationally driven agitator 20 in cooperation with the auxiliary grinding bodies 38. The ground material leaves the interior grinding chamber 8 b through the separating device 32, from where it flows through the grinding stock discharge line 33.

• g ≥ 3i,

wobei für den Durchmesser i gilt:

• i ≤ 3,0 mm und bevorzugt 1 ≤ 1,5 mm.

Absolut gilt für die Spaltweite g des Außen-Mahlraums 8a:

• g ≤ 9,0 mm und bevorzugt g ≤ 5,0 mm.

As can be seen in particular from FIG. 2, the radial gap width g of the outer grinding chamber 8a is significantly smaller than the radial gap width h of the inner grinding chamber 8b. The gap widths g and h are related to each other so that the cross-sectional area Fb of the inner grinding space 8b is equal to or larger than the cross-sectional area Fa of the outer grinding space 8a. Both the outer grinding chamber 8a and the inner grinding chamber 8b are formed as grinding gaps. The following applies to the gap width g of the outer grinding chamber 8a in relation to the diameter i of the largest grinding aid body 38 located in the agitator mill:

• g ≥ 3i,

where for the diameter i:

• i ≤ 3.0 mm and preferably 1 ≤ 1.5 mm.

Absolutely true for the gap width g of the outer grinding chamber 8a:

• g ≤ 9.0 mm and preferably g ≤ 5.0 mm.

• Fa ≤ Fb und bevorzugt 1,2 Fa ≤ Fb ≤ 7 Fa.

For the cross-sectional area Fa of the outer grinding chamber 8a, in relation to the cross-sectional area Fb of the inner grinding chamber 8b:

• Fa ≤ Fb and preferably 1.2 Fa ≤ Fb ≤ 7 Fa.

The embodiment of FIGS. 6 and 7 differs from that of FIGS. 2 to 5 essentially in that between the end plate 44 and the rotor 39 except a Mahlhilfskörper feedback module 45 'still a jam device 62 is provided as part of the agitator 20'. Between the front part 31 of the inner stator 22 and this storage device 62 of the outflow channel 59 'is limited, so deviating from the embodiment of FIGS. 2 to 5 not only on its underside by the front part 31, but also at Unlike in the embodiment according to FIGS. 2 to 5, the inner grinding chamber 8b does not open at its upper end directly into the return channels 54 ', but instead feeds the grinding material. Mahlhilfskörper mixture is forced by the jam device 62 obliquely upwards and inwards in the direction of the separator 32 '. In this embodiment, the gap width j of the outflow channel 59 'is constant.

• e' ≤ f' und insbesondere
• e' ≤ 0,8 f' und ganz besonders
• e' < 0,5 f'.

As far as parts are otherwise identical to those of the embodiment of FIGS. 2 to 5, the same reference numerals are used. Otherwise, the same reference numerals are used for functionally identical and structurally similar parts, to which a superscript bar is added. The same applies to further embodiments with correspondingly several elevated strokes. The height e 'of the return channels 54' is significantly less than the height e in the embodiment of FIGS. 2 to 5. Furthermore, the height e 'is significantly less than the axial height f of the separator 32'. It is thus possible in a simple manner to adjust the height e 'of the return channels 54' to lower grinding stock throughputs and, in addition, to reduce the risk of grinding stock particle passages, in particular with low grinding material throughput or a low rotational speed of the agitator 10. The following applies:

• e '≤ f' and in particular
• e '≤ 0.8 f' and especially
• e '<0.5 f'.

Furthermore, the separating device 32 'does not extend over the full area above the end portion 31. Rather, a closed ring portion as wear protection 63 is provided between the end portion 31 and the separator 32', which is formed integrally with the separator 32 '. Before him or on him the outflow channel ends 59 ', so that from the outflow channel 59' exiting and deflected in an axis-parallel motion Mahlhilfskörper 38, the separator 32 'do not hit.

The embodiment according to FIG. 8 differs from that according to FIGS. 6 and 7 only in that the grinding aid return channels 54 "have a minimum required height e" for trouble-free operation at low grinding stock throughputs. Otherwise, the Mahlhilfskörper feedback module 45 "includes here to the jam means 62, wherein in this embodiment, as in the two aforementioned embodiments, the return channels 54" are bounded on their upper side by the end plate 44. The axial height k is the same in the return modules 45 'and 45 ".

• e" ≥ 3 i mindestens aber e" ≥ 4 mm.

For the minimum axial height e "of the return channels 54", the following applies:

• e "≥ 3 i but at least e" ≥ 4 mm.

The embodiment of FIG. 9 corresponds to that of FIG. 6 with the difference that no wear protection 63 is provided and that on the other hand the outflow channels 59 '' extend towards the grinding aid separator 32, ie the gap width j '' of the outflow channel 59 '' increases inwards to such an extent that the total cross-sectional area of this channel 59 '' In any case, it does not become smaller in the direction of the separating device 32 so that there is no acceleration of the grinding stock auxiliary body flow in the outflow channel 59 '' to the separating device 32. For this reason, the separating device 32 can extend to the front part 31, since the auxiliary grinding bodies 38 do not hit the separator 32.

The embodiment of FIG. 10 substantially corresponds to that of FIG. 9, wherein the Mahlhilfskörper feedback module 45 "" is not brought up to the separator 32. The inlet openings 55 "" of the grinding auxiliary body return channels 54 "" thus have a clear radial distance from the separating device 32. In this annular space 64 a plurality of scrapers 65 are provided, which are attached to the end plate 44 and rotate with the agitator 20 "".

The exemplary embodiment according to FIGS. 11 to 13 has a grinding aid body return module 45 ""'which bears against an intermediate ring 66 toward the accumulation device 62. The module 45 ""'is thus down to the grinding chamber 8, ie to an end face 67, open. The axial height e ""'is constant from the respective inlet opening 55 ""' to the outlet opening 56 ""'and is significantly smaller than the height f' of the separating device 32 '. The scrapers 65 '''merge seamlessly with the return channels 54 "'', so that a continuous transition from these scrapers 65""' is given in the return channels 54""', as Fig. 13 in particular is removable , This leads to optimal flow conditions. As can be seen in FIG. 11, the wipers 65 '''extend in the direction of the axis 19 about the height f 'of the separator 32'.

Claims (18)

1. An agitator mill for treating free-flowing grinding stock, comprising
   a grinding receptacle (2) which defines a substantially closed grinding chamber (8) by means of an inner wall (9); and
   an agitator (20) which is rotarily drivably disposed therein and which is cup-shaped in relation to a common central longitudinal axis (19), having an annular cylindrical rotor (39) which has a closed wall (40, 41); and
   an interior stator (22) which is disposed within the rotor (39) and fixedly joined to the grinding receptacle (2);
   wherein an annular cylindrical exterior grinding chamber (8a) in the form of an annular gap is formed between the inner wall (9) of the grinding receptacle (2) and an outer wall (40) of the rotor (39), the exterior grinding chamber (8a) having a radial gap width g;
   wherein an annular cylindrical interior grinding chamber (8b) in the form of an annular gap is formed between an inner wall (41) of the rotor (39) and an outer casing (23) of the interior stator (22), the interior grinding chamber (8b) being arranged coaxially within the exterior grinding chamber (8a) and connected thereto via a deflection chamber (50) and having a radial gap width h;
   wherein the exterior grinding chamber (8a), the deflection chamber (50) and the interior grinding chamber (8b) constitute the grinding chamber (8) which is partially filled with auxiliary grinding bodies (38);
   wherein a grinding-stock supply area (57), which is disposed upstream of the exterior grinding chamber (8a) and opens into the exterior grinding chamber (8a) in the direction of flow (60) of the grinding stock, and a separator device (32), which is disposed downstream of the interior grinding chamber (8b) in the direction of flow (60), are disposed approximately on the same side of the grinding receptacle (2) for the grinding stock to pass through;
   wherein auxiliary-grinding-body return conduits (54) are provided in the agitator (20) for returning the auxiliary grinding bodies (38) from the vicinity of the separator device (32) into the grinding-stock supply area (57), the return conduits (54) connecting the end of the interior grinding chamber (8b) to the beginning of the exterior grinding chamber (8a);
   wherein the inner wall (9) of the grinding receptacle (2) and the outer wall (40) and the inner wall (41) of the rotor (39) are free of interruptions, and the inner wall (9) of the grinding receptacle (2) and the outer wall (40) of the rotor (39) are smooth and free of agitator implements;
   characterized
   in that g < h applies to the radial gap width g of the exterior grinding chamber (8a) in relation to the radial gap width h of the interior grinding chamber (8b).
2. An agitator mill according to claim 1, characterized
   in that Fa ≤ Fb, and preferably 1.2 Fa ≤ Fb ≤ 7 Fa, applies to the cross-sectional area Fa of the exterior grinding chamber (8a) in relation to the cross-sectional area Fb of the interior grinding chamber (8b).
3. An agitator mill according to claim 1 or 2, characterized
   in that g ≥ 3i applies to the gap width g of the exterior grinding chamber (8a) in relation to the diameter i of the biggest auxiliary grinding bodies (38) in the grinding chamber (8);
   wherein i ≤ 3.0 mm, and preferably i ≤ 1.5 mm, applies to the diameter i of the auxiliary grinding bodies (38);
   and wherein g ≤ 9.0 mm, and preferably g ≤ 5.0 mm, applies to the gap width g of the exterior grinding chamber (8a).
4. An agitator mill according to any of claims 1 to 3, characterized
   in that the outer casing (23) of the interior stator (22) is equipped with elevations which project into the interior grinding chamber (8b).
5. An agitator mill according to claim 4, characterized
   in that the elevations are implements (49), in particular implements in the form of pegs.
6. An agitator mill according to claim 4, characterized
   in that the elevations are disposed helically on the interior stator (22).
7. An agitator mill according to any of claims 1 to 6, characterized
   in that the inner wall (41) of the rotor (39) is smooth, free of agitator implements.
8. An agitator mill according to any of claims 1 to 7, characterized
   in that the interior grinding chamber (8b) is followed by a discharge conduit (59) in the shape of a truncated cone which is directed towards the separator device (32).
9. An agitator mill according to claim 8, characterized
   in that the discharge conduit (59) is defined by a face (31), neighbouring the separator device (32), of the interior stator (22) and a dam-up device (62).
10. An agitator mill according to claim 9, characterized
    in that the dam-up device (62) is an independent component part of the agitator (20).
11. An agitator mill according to claim 8, characterized
    in that the gap width j of the discharge conduit (59) grows in a direction towards the separator device (32).
12. An agitator mill according to any of claims 8 to 11, characterized
    in that the interior stator (22) is provided with a wearing protection (63) in the vicinity of the discharge conduit (59).
13. An agitator mill according to any of claims 8 to 12, characterized
    in that the auxiliary-grinding-body return conduits (54) are formed in an independent auxiliary-grinding-body return module (45).
14. An agitator mill according to claim 13,
    wherein the auxiliary-grinding-body return conduits (54) are open towards a front (67) of the return module (45).
15. An agitator mill according to any of claims 1 to 14, characterized
    in that the return conduits (54) have an inlet (5) of a width c and an outlet (56) of a width d; and
    in that d > c, and preferably d ≥ 1.5 c, applies to the width c of the inlet (55) in relation to the width d of the outlet (56).
16. An agitator mill according to any of claim 1 to 15, characterized
    in that the auxiliary-grinding-body return conduits (54) have a height e and the separator device (32) has a height f - each in the direction of the central longitudinal axis (1); and
    wherein e ≤ f, and preferably e < 0.5 f, applies to the height e in relation to the height f.
17. An agitator mill according to any of claims 13 to 16, characterized
    in that the return module (45), in vicinity to the separator device (32), is provided with wipers (65) which pass continuously without interruption into the return conduits (54).
18. An agitator mill according to claim 17, characterized
    in that the wipers (65) extend along the height (f) of the auxiliary-grinding-body separator device (32).

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