[go: up one dir, main page]

EP0376001B1 - Agitator mill with a separating device in a rotating cage - Google Patents

Agitator mill with a separating device in a rotating cage Download PDF

Info

Publication number
EP0376001B1
EP0376001B1 EP89122340A EP89122340A EP0376001B1 EP 0376001 B1 EP0376001 B1 EP 0376001B1 EP 89122340 A EP89122340 A EP 89122340A EP 89122340 A EP89122340 A EP 89122340A EP 0376001 B1 EP0376001 B1 EP 0376001B1
Authority
EP
European Patent Office
Prior art keywords
zone
agitator mill
grinding
cage
inlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP89122340A
Other languages
German (de)
French (fr)
Other versions
EP0376001A1 (en
Inventor
Erwin Weber
Giacomo Dr. Canepa
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Erich Netzsch GmbH and Co Holding KG
Original Assignee
Erich Netzsch GmbH and Co Holding KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE19883844380 external-priority patent/DE3844380C1/en
Application filed by Erich Netzsch GmbH and Co Holding KG filed Critical Erich Netzsch GmbH and Co Holding KG
Publication of EP0376001A1 publication Critical patent/EP0376001A1/en
Application granted granted Critical
Publication of EP0376001B1 publication Critical patent/EP0376001B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16—Mills in which a fixed container houses stirring means tumbling the charge
    • B02C17/161—Arrangements for separating milling media and ground material

Definitions

  • the invention relates to an agitator mill with a grinding container and an agitator shaft rotatably arranged therein, which jointly delimit a grinding chamber, a grist inlet, a cage which rotates as part of the agitator shaft and is open at one end, and a separating device which in the Cage is arranged, holds back unprocessed regrind and any auxiliary grinding media contained in the grinding chamber, but allows processed regrind to flow out to a regrind outlet, the grinding chamber being subdivided into an inlet zone which adjoins the regrind inlet and at least for a substantial part of its length from the agitator shaft is axially penetrated, and a separation zone which adjoins the inlet zone in the axial direction and is arranged around the cage.
  • the separation zone extends over a maximum of 25% of the total length of the grinding chamber; at least 75% of this total length is taken up by the inlet zone.
  • the separating device has an effective surface, the size of which is generally between 5% and 10% of the size of the inner surface of the grinding container which delimits the grinding chamber. Consequently the separator significantly inhibits the discharge of the ground material from the grinding chamber.
  • the speed component of the regrind flow in the axial direction of the grinding container is therefore relatively low, and there is a high probability that each individual particle of the regrind is crushed to the desired size on the long way between the regrind inlet and the separating device.
  • the throughput per unit of time is not too great for a given size of the known mill. This is particularly evident in cases in which a single pass of the millbase through the grinding chamber of an agitator mill is not sufficient to achieve the desired size reduction, and it is therefore necessary to either pump the millbase several times through the grinding chamber or to pump it several times pump back and forth between a storage container and the grinding chamber.
  • the invention is based on the object of substantially increasing the size reduction per unit time in an agitator mill and thereby achieving a particularly uniform size reduction of the ground material.
  • the object is achieved based on an agitator mill of the type described above in that the separation zone extends over 40% to 80% of the total length of the grinding chamber and the separating device has an effective area, the size of which is at least 20% of the inner surface of the grinding container delimiting the grinding chamber is.
  • the effective area of the separating device is to be understood as that surface of the separating device which is provided with meshes or with annular gaps located between separating rings.
  • An agitator mill according to the invention is flowed through relatively quickly because of the relatively long length of the separation zone and the relatively large effective area of the separation device, so that for each individual regrind particle the likelihood of being sufficiently comminuted in a single pass through the grinding chamber is low. Therefore, the individual particles of the material to be ground have to be conveyed through the grinding chamber much more frequently than in known generic agitator mills before they have undergone the desired comminution. Surprisingly, it has been found that the agitator mill according to the invention can nevertheless achieve a significantly higher comminution performance than in known generic agitator mills. The uniformity of the shredding is further increased. Because of the short average residence time of the individual regrind particles in the agitator mill, the risk of the regrind being damaged by overheating is generally lower than in the prior art.
  • Each of the agitator mills shown has an essentially cylindrical grinding container 10, in which a stirring shaft 12 is mounted coaxially, as well as a grinding material inlet 14 and a separating device 16, to which a grinding material outlet 18 connects.
  • a grinding chamber 20 is formed between the grinding container 10 and the stirring shaft 12 each of the agitator mills shown includes an inlet zone 22 and a separation zone 24.
  • the inlet zone 22 contains the regrind inlet 14 (FIGS. 1 and 7 to 11) or it adjoins this in the axial direction (FIGS. 2 to 6).
  • the separation zone 24 follows the inlet zone 22 in the axial direction and is arranged around a cage 25 which is formed on the agitator shaft 12, is at least approximately cylindrical, encloses the separation device 16 and is open at one end at the end.
  • the length of the separation zone 24 is the same as the length of the cage 25.
  • the separating device 16 can be formed by individual separating rings or a mesh screen, is at least approximately cylindrical in all the examples shown and has an effective length which corresponds at least approximately to the length of the cage 25 and thus also to the length of the separating zone 24.
  • the length of the separating device 16, measured in the axial direction of the agitator shaft 12, is approximately half (FIGS. 1 to 8, 10 and 11) to two thirds (FIG. 9) of the total length of the grinding chamber 20. That for the throughput relevant active lateral surface of the separating device 16 has an outer diameter which is only slightly smaller than the inner diameter of the cage 25.
  • the product length by diameter of the active outer surface of the separating device 16 is approximately 20% to 25% of the product length by diameter of the inner outer surface of the grinding container 10.
  • the agitator mills shown in FIGS. 1 to 5 and in FIGS. 7 to 11 are arranged horizontally, that is to say with a horizontal agitator shaft 12; 6, on the other hand, a standing agitator mill is shown.
  • the regrind inlet 14 is formed by bores in the agitator shaft 12.
  • the agitator shaft 12 is slim; its outside diameter is about a quarter to a third of the inside diameter of the grinding container 10. Towards the end of the inlet zone 22, the outside diameter of the stirring shaft 12 increases steadily to approximately two thirds of the inside diameter of the grinding container 10; the agitator shaft 12 maintains this large diameter in the separation zone 24.
  • the part of the agitator shaft 12 arranged in the inlet zone 22 carries agitator elements 26; 1, these are formed by long radial pins which extend up to close to the cylindrical inner wall of the grinding container 10.
  • the cage 25 of the agitator shaft 12 arranged in the separation zone 24 also carries agitator elements 28 which, however, are formed by short radial pins.
  • the grinding chamber 20 is, as indicated in FIG. 1, partially filled with regrind 30 and auxiliary grinding bodies 32.
  • the cage 25 has slots 34 which are parallel to the axis and is open on its end face facing the regrind outlet 18.
  • the separating device 16 is formed by a cylindrical sieve which is arranged coaxially with the stirring shaft 12 and is fastened to the grinding container 10.
  • a packing 36 is arranged coaxially with it, which leaves a relatively narrow annular space 38, which widens towards the grinding material outlet 18, between itself and the separating device 16.
  • Processing of the grinding stock 30 takes place predominantly in the inlet zone 22, in which the auxiliary grinding bodies 32 are strongly activated by the long stirring elements 26.
  • the regrind inlet 14 is not endangered because of its relatively protected arrangement from fast moving Grinding auxiliary bodies 32 are hit in considerable numbers and are therefore quickly worn out.
  • the short stirring elements 28 in the separation zone 24 essentially only have the task of avoiding or loosening up aggregates of auxiliary grinding bodies 32.
  • the ground material 30 mixed with auxiliary grinding bodies 32 flows from the inlet zone 22 through the separation zone 24 and passes through the open end face of the agitator shaft 12 into its cage 25. From there, the processed ground material 30 flows through the separating device 16 and the annular space 38 to the ground material outlet 18.
  • the auxiliary grinding bodies 32 are thrown outwards through the slots 34 and then repeat their cycle.
  • the agitator mill according to FIG. 2 differs from that shown in FIG. 1 essentially in that the ground material inlet 14 is arranged on the end of the grinding container 10 and opens directly into the grinding chamber 20. Furthermore, counter elements 40 in the form of radial pins are attached to the cylindrical inner wall of the grinding container 10 in the inlet zone 22 and extend between the stirring elements 26 to close to the stirring shaft 12.
  • the agitator shaft 12 contains an axial coolant channel 42; this extends from the drive-side end of the agitator shaft 12 on the left in the drawings into the filler body 36 which, according to FIG. 2, is formed in one piece with the agitator shaft 12 or is fastened to it.
  • the separating device 16 is again a cylindrical sieve according to FIG. 2, but, in contrast to FIG. 1, is not attached to the grinding container 10 but to the stirring shaft 12, so that the separating device 16 rotates together with the stirring shaft 12.
  • 22 stirring elements 26 are attached to the agitator shaft 12 in the inlet zone, which are circular or else non-circular disks are formed.
  • the separating device 16 is, to the extent that it corresponds to FIG. 1, attached to the grinding container 10, but is formed according to FIG. 3 by a ring arrangement with radial gaps arranged between the individual rings.
  • the stirring shaft 12 is not provided with stirring elements; the cage 25 arranged around the separating device 16, however, because of its slots 34, ensures sufficient movement of the grinding material 30 and grinding auxiliary bodies 32 in the separation zone 24 for different types of grinding material.
  • the embodiment according to FIG. 4 differs from that shown in FIG. 3 primarily in that in the inlet zone 22 on the grinding container 10 between the disk-shaped stirring elements 26 are fixed counter-elements 40 which, as in FIG. 2, are formed by radial rods. 4, the stirrer shaft 12 has a solid shaft core 44, on which the disk-shaped stirrer elements 26, a spacer sleeve 46 arranged between them and a hollow shaft part 48 supporting the cage 25 are attached.
  • the outer contours of the agitator shaft 12 are the same as in FIG. 4 as in FIG. 3; the left-hand disc-shaped stirring element 26 in FIG.
  • the separating device 16 is designed as in FIGS. 3 and 4, but according to FIG. 5 it only has the task of retaining coarse regrind particles and only allowing processed regrind to reach the regrind outlet 18.
  • the agitator shaft 12 is overhung in all the examples shown; A bearing 52 and shaft seal 54 is therefore only, as indicated, arranged at one end of the grinding container 10. At this end or in the vicinity thereof, a drive of conventional design is coupled or can be coupled to the agitator shaft 12.
  • the separating device 16 is arranged in each of the agitator mills shown in FIGS. 1 to 5 and in FIGS. 7 to 11 in the half of the grinding container 10 remote from the drive and bearing 52.
  • the separating device 16 is arranged in the drive-side half of the grinding container 10 and connected to the grinding material outlet 18 via a discharge chamber 56 which adjoins the shaft seal 54.
  • the stirring elements 26 are accordingly attached to or in the vicinity of the free end of the stirring shaft 12.
  • the agitator shaft 12 is slim only in the area of the bearing 52 and shaft seal 54 up to the beginning of the inlet zone 22; here it has a diameter of the order of a quarter to a third of the inside diameter of the grinding container 10.
  • a cone 58 belonging to the agitator shaft 12 begins, which has a complementarily conical inner end wall 60 of the grinding container 10 conical friction gap 62 limited.
  • the conical friction gap 62 is followed by a cylindrical friction gap 64 of approximately the same width, which extends to the end of the inlet zone 22.
  • the ground material 30 is activated in the friction gaps 62 and 64 by friction between the walls of the grinding container 10 and the agitator shaft 12 that delimit these friction gaps.
  • the agitator shaft 12 In the separation zone 24, around the separation device 16, the agitator shaft 12 has an outer diameter that is slightly smaller than the largest diameter of the cone 58.
  • Fig. 8 agrees with Fig. 7 in that the outer diameter of the agitator shaft 12 increases axially within the shaft seal 54 at a short distance.
  • the stirring shaft 12 has an outer diameter which is approximately two thirds of the inner diameter of the grinding container 10.
  • the stirring shaft 12 carries stirring elements 26 in the form of relatively short radial pins.
  • Counter-elements 40 also in the form of short radial pins, but attached to the inner wall of the grinding container 10, are only present in the inlet zone 22; the entire separation zone 24 around the separation device 16 is free of such counter-elements 40.
  • the agitator mill according to FIG. 9 corresponds to that shown in FIG. 7 in the design of the cone 58 and the inner end wall 60 of the grinding container 10; thus a conical friction gap 62 and a cylindrical friction gap 64 are also present here.
  • the cylindrical friction gap 64 is, however, much shorter since the cone 58 ends with a collar 66 which is narrow in the axial direction and the cage 25 begins immediately behind it, to the right of this in accordance with FIG. 9. whose outer diameter is considerably smaller than that of the collar 66.
  • the length of the cage 25, and thus the separation zone 24, is approximately three quarters of the length of the grinding chamber 20.
  • the cage 25 is equipped with pin-shaped stirring elements 28, between those fastened to the grinding container 10, pin-shaped counter-elements 40 also project radially inwards.
  • regrind 30 and auxiliary grinding body 32 are relatively strongly activated in the separation zone 24; the auxiliary grinding bodies 32 activated in this way are, however, reliably prevented by the collar 66 from entering the region of the grinding material inlet 14. As a result, it is particularly well protected against wear.
  • the cage 25, starting from its open free end, is divided into three areas which adjoin one another in the axial direction, namely an area 66 starting near the open end of the cage and provided with axially parallel, radially continuous slots 34 is a closed central region 68 which is completely free of such slots and a region 70 which is distant from the open end of the cage and in which radially continuous axially parallel slots 34 are again provided.
  • the closed central region 68 of the cage 25 is approximately half as long as the separation zone 24.
  • the cage 25 is completely closed not only in its central region 68 but also in its region adjacent to the open end of the cage; Radially continuous, axially parallel slots 34 or other openings through which grinding aid bodies 32 can exit the cage 25 are arranged only in the region 70 which is distant from the open end of the cage and extends around the end region 72 of the separating device 16.

Landscapes

  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Crushing And Grinding (AREA)

Description

Die Erfindung betrifft eine Rührwerksmühle mit einem Mahlbehälter und einer in diesem drehbar angeordneten Rührwelle, die gemeinsam einen Mahlraum begrenzen, einem Mahlguteinlaß, einem Käfig, der als Bestandteil der Rührwelle mit dieser rotiert und an einem Ende offen ist, und einer Trennvorrichtung, die in dem Käfig angeordnet ist, unbearbeitetes Mahlgut und ggf. im Mahlraum enthaltene Mahlhilfskörper zurückhält, bearbeitetes Mahlgut jedoch zu einem Mahlgutauslaß abströmen läßt, wobei der Mahlraum unterteilt ist in eine Einlaßzone, die sich an den Mahlguteinlaß anschließt und mindestens auf einem wesentlichen Teil ihrer Länge von der Rührwelle axial durchsetzt ist, und eine Trennzone, die sich in axialer Richtung an die Einlaßzone anschließt und rings um den Käfig angeordnet ist.The invention relates to an agitator mill with a grinding container and an agitator shaft rotatably arranged therein, which jointly delimit a grinding chamber, a grist inlet, a cage which rotates as part of the agitator shaft and is open at one end, and a separating device which in the Cage is arranged, holds back unprocessed regrind and any auxiliary grinding media contained in the grinding chamber, but allows processed regrind to flow out to a regrind outlet, the grinding chamber being subdivided into an inlet zone which adjoins the regrind inlet and at least for a substantial part of its length from the agitator shaft is axially penetrated, and a separation zone which adjoins the inlet zone in the axial direction and is arranged around the cage.

Bei bekannten Rührwerksmühlen dieser Gattung (EP 0146852 B1) erstreckt sich die Trennzone über höchstens 25% der Gesamtlänge des Mahlraums; mindestens 75% dieser Gesamtlänge werden von der Einlaßzone eingenommen. Die Trennvorrichtung hat eine wirksame Fläche, deren Größe im allgemeinen zwischen 5% und 10% der Größe der den Mahlraum begrenzenden Innenfläche des Mahlbehälters beträgt. Infolgedessen hemmt die Trennvorrichtung den Abfluß des Mahlgutes aus dem Mahlraum erheblich. Die Geschwindigkeitskomponente der Mahlgutströmung in Achsrichtung des Mahlbehälters ist deshalb verhältnismäßig gering, und es besteht eine hohe Wahrscheinlichkeit, daß jedes einzelne Partikel des Mahlgutes auf dem langen Weg zwischen Mahlguteinlaß und Trennvorrichtung auf die gewünschte Größe zerkleinert wird. Der Durchsatz je Zeiteinheit ist jedoch bei gegebener Baugröße der bekannten Mühle nicht allzu groß. Dies zeigt sich vor allem in Fällen, in denen ein einziger Durchgang des Mahlgutes durch den Mahlraum einer Rührwerksmühle nicht ausreicht, um die gewünschte Zerkleinerung zu erreichen, und es deshalb nötig ist, das Mahlgut entweder im Kreislauf mehrere Male durch den Mahlraum hindurchzupumpen oder es mehrfach zwischen einem Vorratsbehälter und dem Mahlraum hin- und herzupumpen.In known agitator mills of this type (EP 0146852 B1), the separation zone extends over a maximum of 25% of the total length of the grinding chamber; at least 75% of this total length is taken up by the inlet zone. The separating device has an effective surface, the size of which is generally between 5% and 10% of the size of the inner surface of the grinding container which delimits the grinding chamber. Consequently the separator significantly inhibits the discharge of the ground material from the grinding chamber. The speed component of the regrind flow in the axial direction of the grinding container is therefore relatively low, and there is a high probability that each individual particle of the regrind is crushed to the desired size on the long way between the regrind inlet and the separating device. However, the throughput per unit of time is not too great for a given size of the known mill. This is particularly evident in cases in which a single pass of the millbase through the grinding chamber of an agitator mill is not sufficient to achieve the desired size reduction, and it is therefore necessary to either pump the millbase several times through the grinding chamber or to pump it several times pump back and forth between a storage container and the grinding chamber.

Der Erfindung liegt die Aufgabe zugrunde, bei einer Rührwerksmühle die Zerkleinerungsleistung je Zeiteinheit wesentlich zu steigern und dabei eine besonders gleichmäßige Zerkleinerung des Mahlgutes zu erreichen.The invention is based on the object of substantially increasing the size reduction per unit time in an agitator mill and thereby achieving a particularly uniform size reduction of the ground material.

Die Aufgabe ist erfindungsgemäß ausgehend von einer Rührwerksmühle der eingangs beschriebenen Gattung dadurch gelöst, daß die Trennzone sich über 40% bis 80% der Gesamtlänge des Mahlraums erstreckt und die Trennvorrichtung eine wirksame Fläche hat, deren Größe mindestens 20% der den Mahlraum begrenzenden Innenfläche des Mahlbehälters beträgt.The object is achieved based on an agitator mill of the type described above in that the separation zone extends over 40% to 80% of the total length of the grinding chamber and the separating device has an effective area, the size of which is at least 20% of the inner surface of the grinding container delimiting the grinding chamber is.

Unter wirksamer Fläche der Trennvorrichtung ist im Sinne dieser Erfindung diejenige Oberfläche der Trennvorrichtung zu verstehen, die mit Siebmaschen oder mit zwischen Trennringen liegenden Ringspalten versehen ist.For the purposes of this invention, the effective area of the separating device is to be understood as that surface of the separating device which is provided with meshes or with annular gaps located between separating rings.

Eine erfindungsgemäße Rührwerksmühle wird wegen der verhältnismäßig großen Länge der Trennzone und der verhältnismäßig großen wirksamen Fläche der Trennvorrichtung verhältnismäßig schnell durchströmt, so daß für jedes einzelne Mahlgutpartikel die Wahrscheinlichkeit, bei einem einzigen Durchgang durch den Mahlraum ausreichend zerkleinert zu werden, gering ist. Deshalb müssen die einzelnen Partikel des Mahlgutes im statistischen Mittel sehr viel häufiger als bei bekannten gattungsgemäßen Rührwerksmühlen durch den Mahlraum hindurchgefördert werden, ehe sie die gewünschte Zerkleinerung erfahren haben. Überraschenderweise hat sich herausgestellt, daß mit der erfindungsgemäßen Rührwerksmühle dennoch eine wesentlich höhere Zerkleinerungsleistung erreichbar ist als bei bekannten gattungsgemäßen Rührwerksmühlen. Dabei wird die Gleichmäßigkeit der Zerkleinerung noch gesteigert. Wegen der im Durchschnitt kurzen Verweilzeit der einzelnen Mahlgutpartikel in der Rührwerksmühle ist die Gefahr, daß das Mahlgut durch Überhitzung geschädigt wird, grundsätzlich geringer als beim vorausgesetzten Stand der Technik.An agitator mill according to the invention is flowed through relatively quickly because of the relatively long length of the separation zone and the relatively large effective area of the separation device, so that for each individual regrind particle the likelihood of being sufficiently comminuted in a single pass through the grinding chamber is low. Therefore, the individual particles of the material to be ground have to be conveyed through the grinding chamber much more frequently than in known generic agitator mills before they have undergone the desired comminution. Surprisingly, it has been found that the agitator mill according to the invention can nevertheless achieve a significantly higher comminution performance than in known generic agitator mills. The uniformity of the shredding is further increased. Because of the short average residence time of the individual regrind particles in the agitator mill, the risk of the regrind being damaged by overheating is generally lower than in the prior art.

Vorteilhafte Weiterbildungen der Erfindung sind Gegenstand der Unteransprüche.Advantageous developments of the invention are the subject of the dependent claims.

Ausführungsbeispiele der Erfindung werden im folgenden anhand schematischer Zeichnungen mit weiteren Einzelheiten erläutert. In Fig. 1 bis 11 ist je eine Rührwerksmühle in einem axialen Längsschnitt dargestellt.Exemplary embodiments of the invention are explained in more detail below with the aid of schematic drawings. 1 to 11 each show an agitator mill in an axial longitudinal section.

Jede der dargestellten Rührwerksmühlen hat einen im wesentlichen zylindrischen Mahlbehälter 10, in dem eine Rührwelle 12 gleichachsig gelagert ist, sowie einen Mahlguteinlaß 14 und eine Trennvorrichtung 16, an die sich ein Mahlgutauslaß 18 anschließt. Zwischen Mahlbehälter 10 und Rührwelle 12 ist ein Mahlraum 20 ausgebildet, der bei jeder der dargestellten Rührwerksmühlen eine Einlaßzone 22 und eine Trennzone 24 enthält. Die Einlaßzone 22 enthält den Mahlguteinlaß 14 (Fig. 1 und 7 bis 11) oder sie schließt sich in axialer Richtung an diesen an (Fig. 2 bis 6). Die Trennzone 24 folgt in axialer Richtung auf die Einlaßzone 22 und ist rings um einen Käfig 25 angeordnet, der an der Rührwelle 12 ausgebildet ist, mindestens annähernd zylindrisch ist, die Trennvorrichtung 16 umschließt und an einem Ende stirnseitig offen ist. Die Länge der Trennzone 24 ist der Länge des Käfigs 25 gleich.Each of the agitator mills shown has an essentially cylindrical grinding container 10, in which a stirring shaft 12 is mounted coaxially, as well as a grinding material inlet 14 and a separating device 16, to which a grinding material outlet 18 connects. A grinding chamber 20 is formed between the grinding container 10 and the stirring shaft 12 each of the agitator mills shown includes an inlet zone 22 and a separation zone 24. The inlet zone 22 contains the regrind inlet 14 (FIGS. 1 and 7 to 11) or it adjoins this in the axial direction (FIGS. 2 to 6). The separation zone 24 follows the inlet zone 22 in the axial direction and is arranged around a cage 25 which is formed on the agitator shaft 12, is at least approximately cylindrical, encloses the separation device 16 and is open at one end at the end. The length of the separation zone 24 is the same as the length of the cage 25.

Die Trennvorrichtung 16 kann von einzelnen Trennringen oder einem Maschensieb gebildet sein, ist in allen dargestellten Beispielen mindestens annähernd zylindrisch und hat eine wirksame Länge, die mindestens annähernd mit der Länge des Käfigs 25, und somit auch mit der Länge der Trennzone 24 übereinstimmt. In allen dargestellten Ausführungsbeispielen beträgt die Länge der Trennvorrichtung 16, in Achsrichtung der Rührwelle 12 gemessen, ungefähr die Hälfte (Fig. 1 bis 8, 10 und 11) bis zwei Drittel (Fig. 9) der Gesamtlänge des Mahlraums 20. Die für den Durchsatz maßgebliche aktive Mantelfläche der Trennvorrichtung 16 hat einen Außendurchmesser, der nur wenig kleiner als der Innendurchmesser des Käfigs 25 ist. Das Produkt Länge mal Durchmesser der aktiven Mantelfläche der Trennvorrichtung 16 beträgt ungefähr 20% bis 25% des Produkts Länge mal Durchmesser der inneren Mantelfläche des Mahlbehälters 10.The separating device 16 can be formed by individual separating rings or a mesh screen, is at least approximately cylindrical in all the examples shown and has an effective length which corresponds at least approximately to the length of the cage 25 and thus also to the length of the separating zone 24. In all of the illustrated exemplary embodiments, the length of the separating device 16, measured in the axial direction of the agitator shaft 12, is approximately half (FIGS. 1 to 8, 10 and 11) to two thirds (FIG. 9) of the total length of the grinding chamber 20. That for the throughput relevant active lateral surface of the separating device 16 has an outer diameter which is only slightly smaller than the inner diameter of the cage 25. The product length by diameter of the active outer surface of the separating device 16 is approximately 20% to 25% of the product length by diameter of the inner outer surface of the grinding container 10.

Die in Fig. 1 bis 5 sowie in Fig. 7 bis 11 dargestellten Rührwerksmühlen sind liegend, also mit waagerechter Rührwelle 12, angeordnet; in Fig. 6 ist hingegen eine stehende Rührwerksmühle dargestellt.The agitator mills shown in FIGS. 1 to 5 and in FIGS. 7 to 11 are arranged horizontally, that is to say with a horizontal agitator shaft 12; 6, on the other hand, a standing agitator mill is shown.

Bei der in Fig. 1 dargestellten Rührwerksmühle ist der Mahlguteinlaß 14 von Bohrungen der Rührwelle 12 gebildet.In the agitator mill shown in FIG. 1, the regrind inlet 14 is formed by bores in the agitator shaft 12.

Vom Anfang bis gegen Ende der Einlaßzone 22 ist die Rührwelle 12 schlank; ihr Außendurchmesser beträgt etwa ein Viertel bis ein Drittel vom Innendurchmesser des Mahlbehälters 10. Gegen Ende der Einlaßzone 22 steigt der Außendurchmesser der Rührwelle 12 stetig auf ungefähr zwei Drittel des Innendurchmessers des Mahlbehälters 10; diesen großen Durchmesser behält die Rührwelle 12 in der Trennzone 24 bei.From the beginning to the end of the inlet zone 22, the agitator shaft 12 is slim; its outside diameter is about a quarter to a third of the inside diameter of the grinding container 10. Towards the end of the inlet zone 22, the outside diameter of the stirring shaft 12 increases steadily to approximately two thirds of the inside diameter of the grinding container 10; the agitator shaft 12 maintains this large diameter in the separation zone 24.

Der in der Einlaßzone 22 angeordnete Teil der Rührwelle 12 trägt Rührelemente 26; diese sind gemäß Fig. 1 von langen radialen Stiften gebildet, die sich bis nahe an die zylindrische Innenwand des Mahlbehälters 10 erstrecken. Der in der Trennzone 24 angeordnete Käfig 25 der Rührwelle 12 trägt ebenfalls Rührelemente 28, die jedoch von kurzen radialen Stiften gebildet sind. Der Mahlraum 20 ist, wie in Fig. 1 angedeutet, mit Mahlgut 30 und Mahlhilfskörpern 32 teilweise gefüllt.The part of the agitator shaft 12 arranged in the inlet zone 22 carries agitator elements 26; 1, these are formed by long radial pins which extend up to close to the cylindrical inner wall of the grinding container 10. The cage 25 of the agitator shaft 12 arranged in the separation zone 24 also carries agitator elements 28 which, however, are formed by short radial pins. The grinding chamber 20 is, as indicated in FIG. 1, partially filled with regrind 30 and auxiliary grinding bodies 32.

Der Käfig 25 weist gemäß Fig. 1 achsparallele Schlitze 34 auf und ist an seiner dem Mahlgutauslaß 18 zugewandten Stirnseite offen. Die Trennvorrichtung 16 ist von einem zylindrischen Sieb gebildet, das gleichachsig mit der Rührwelle 12 angeordnet und am Mahlbehälter 10 befestigt ist. Innerhalb der Trennvorrichtung 16 ist gleichachsig mit ihr ein Füllkörper 36 angeordnet, der zwischen sich und der Trennvorrichtung 16 einen verhältnismäßig schmalen, sich zum Mahlgutauslaß 18 erweiternden Ringraum 38 freiläßt.According to FIG. 1, the cage 25 has slots 34 which are parallel to the axis and is open on its end face facing the regrind outlet 18. The separating device 16 is formed by a cylindrical sieve which is arranged coaxially with the stirring shaft 12 and is fastened to the grinding container 10. Within the separating device 16, a packing 36 is arranged coaxially with it, which leaves a relatively narrow annular space 38, which widens towards the grinding material outlet 18, between itself and the separating device 16.

Eine Bearbeitung des Mahlgutes 30 findet vorwiegend in der Einlaßzone 22 statt, in der die Mahlhilfskörper 32 von den langen Rührelementen 26 kräftig aktiviert werden. Der Mahlguteinlaß 14 ist wegen seiner verhältnismäßig geschützten Anordnung dennoch nicht gefährdet, von schnell bewegten Mahlhilfskörpern 32 in erheblicher Anzahl getroffen und dadurch rasch verschlissen zu werden. Die kurzen Rührelemente 28 in der Trennzone 24 haben im wesentlichen nur die Aufgabe, Zusammenballungen von Mahlhilfskörpern 32 zu vermeiden oder aufzulockern.Processing of the grinding stock 30 takes place predominantly in the inlet zone 22, in which the auxiliary grinding bodies 32 are strongly activated by the long stirring elements 26. The regrind inlet 14 is not endangered because of its relatively protected arrangement from fast moving Grinding auxiliary bodies 32 are hit in considerable numbers and are therefore quickly worn out. The short stirring elements 28 in the separation zone 24 essentially only have the task of avoiding or loosening up aggregates of auxiliary grinding bodies 32.

Das mit Mahlhilfskörpern 32 durchmischte Mahlgut 30 strömt von der Einlaßzone 22 durch die Trennzone 24 und gelangt durch die offene Stirnseite der Rührwelle 12 in deren Käfig 25. Von dort aus strömt das bearbeitete Mahlgut 30 durch die Trennvorrichtung 16 und den Ringraum 38 zum Mahlgutauslaß 18. Die Mahlhilfskörper 32 werden hingegen durch die Schlitze 34 hindurch nach außen geschleudert und wiederholen dann ihren Kreislauf.The ground material 30 mixed with auxiliary grinding bodies 32 flows from the inlet zone 22 through the separation zone 24 and passes through the open end face of the agitator shaft 12 into its cage 25. From there, the processed ground material 30 flows through the separating device 16 and the annular space 38 to the ground material outlet 18. The auxiliary grinding bodies 32, on the other hand, are thrown outwards through the slots 34 and then repeat their cycle.

Die Rührwerksmühle gemäß Fig. 2 unterscheidet sich von der in Fig. 1 dargestellten im wesentlichen dadurch, daß der Mahlguteinlaß 14 stirnseitig am Mahlbehälter 10 angeordnet ist und unmittelbar in den Mahlraum 20 mündet. Ferner sind an der zylindrischen Innenwand des Mahlbehälters 10 in der Einlaßzone 22 Gegenelemente 40 in Form radialer Stifte befestigt, die sich zwischen den Rührelementen 26 bis nahe an die Rührwelle 12 erstrecken. Außerdem enthält die Rührwelle 12 einen axialen Kühlmittelkanal 42; dieser erstreckt sich vom antriebsseitigen, in den Zeichnungen linken Ende der Rührwelle 12 bis in den Füllkörper 36 hinein, der gemäß Fig. 2 mit der Rührwelle 12 einstückig ausgebildet oder an ihr befestigt ist. Die Trennvorrichtung 16 ist gemäß Fig. 2 wiederum ein zylindrisches Sieb, ist aber im Gegensatz zu Fig. 1 nicht am Mahlbehälter 10, sondern an der Rührwelle 12 befestigt, so daß die Trennvorrichtung 16 sich zusammen mit der Rührwelle 12 dreht.The agitator mill according to FIG. 2 differs from that shown in FIG. 1 essentially in that the ground material inlet 14 is arranged on the end of the grinding container 10 and opens directly into the grinding chamber 20. Furthermore, counter elements 40 in the form of radial pins are attached to the cylindrical inner wall of the grinding container 10 in the inlet zone 22 and extend between the stirring elements 26 to close to the stirring shaft 12. In addition, the agitator shaft 12 contains an axial coolant channel 42; this extends from the drive-side end of the agitator shaft 12 on the left in the drawings into the filler body 36 which, according to FIG. 2, is formed in one piece with the agitator shaft 12 or is fastened to it. The separating device 16 is again a cylindrical sieve according to FIG. 2, but, in contrast to FIG. 1, is not attached to the grinding container 10 but to the stirring shaft 12, so that the separating device 16 rotates together with the stirring shaft 12.

Gemäß Fig. 3 sind an der Rührwelle 12 in der Einlaßzone 22 Rührelemente 26 befestigt, die von kreisförmigen oder auch unrunden Scheiben gebildet sind. Die Trennvorrichtung 16 ist, insoweit übereinstimmend mit Fig. 1, am Mahlbehälter 10 befestigt, ist jedoch gemäß Fig. 3 von einer Ringanordnung mit zwischen den einzelnen Ringen angeordneten radialen Spalten gebildet. In der Trennzone 24 ist die Rührwelle 12 nicht mit Rührelementen versehen; der rings um die Trennvorrichtung 16 angeordnete Käfig 25 sorgt aber wegen seiner Schlitze 34 für eine bei verschiedenen Mahlgutarten ausreichende Bewegung von Mahlgut 30 und Mahlhilfskörpern 32 in der Trennzone 24.3, 22 stirring elements 26 are attached to the agitator shaft 12 in the inlet zone, which are circular or else non-circular disks are formed. The separating device 16 is, to the extent that it corresponds to FIG. 1, attached to the grinding container 10, but is formed according to FIG. 3 by a ring arrangement with radial gaps arranged between the individual rings. In the separation zone 24, the stirring shaft 12 is not provided with stirring elements; the cage 25 arranged around the separating device 16, however, because of its slots 34, ensures sufficient movement of the grinding material 30 and grinding auxiliary bodies 32 in the separation zone 24 for different types of grinding material.

Die Ausführungsform gemäß Fig. 4 unterscheidet sich von der in Fig. 3 dargestellten vor allem dadurch, daß in der Einlaßzone 22 am Mahlbehälter 10 zwischen den scheibenförmigen Rührelementen 26 ortsfeste Gegenelemente 40 befestigt sind, die wie in Fig. 2 von radialen Stäben gebildet sind. Die Rührwelle 12 hat gemäß Fig. 4 einen massiven Wellenkern 44, auf den die scheibenförmigen Rührelemente 26, eine zwischen diesen angeordnete Distanzbüchse 46 sowie ein den Käfig 25 tragender hohler Wellenteil 48 aufgesteckt sind. Die äußeren Umrisse der Rührwelle 12 sind gemäß Fig. 4 die gleichen wie gemäß Fig. 3; das in Fig. 4 linke scheibenförmige Rührelement 26 hat jedoch radiale Schlitze 50, die in ihrer Form und Anordnung den stiftförmigen Gegenelementen 40 entsprechen und erforderlich sind, damit sich dieses Rührelement 26 auf den Wellenkern 44 aufstecken läßt, während dieser schon in den Mahlbehälter 10 eingebaut ist oder bevor der Wellenkern 44 gemäß Fig. 4 von rechts nach links eingeschoben wird.The embodiment according to FIG. 4 differs from that shown in FIG. 3 primarily in that in the inlet zone 22 on the grinding container 10 between the disk-shaped stirring elements 26 are fixed counter-elements 40 which, as in FIG. 2, are formed by radial rods. 4, the stirrer shaft 12 has a solid shaft core 44, on which the disk-shaped stirrer elements 26, a spacer sleeve 46 arranged between them and a hollow shaft part 48 supporting the cage 25 are attached. The outer contours of the agitator shaft 12 are the same as in FIG. 4 as in FIG. 3; the left-hand disc-shaped stirring element 26 in FIG. 4 has radial slots 50 which correspond in shape and arrangement to the pin-shaped counter elements 40 and are necessary for this stirring element 26 to be plugged onto the shaft core 44 while it is already being installed in the grinding container 10 4 or before the shaft core 44 is pushed in from right to left according to FIG. 4.

Während die in Fig. 1 bis 4 sowie die in Fig. 6 bis 11 dargestellten Rührwerksmühlen dazu vorgesehen sind, mit Mahlhilfskörpern 32 betrieben zu werden, weist die in Fig. 5 dargestellte Rührwerksmühle Rührelemente 26 in Form gezahnter Dispergierscheiben auf, die einen Betrieb ohne Mahlhilfskörper ermöglichen. Die Trennvorrichtung 16 ist wie in Fig. 3 und 4 gestaltet, hat jedoch gemäß Fig. 5 nur die Aufgabe, grobe Mahlgutpartikel zurückzuhalten und nur bearbeitetes Mahlgut zum Mahlgutauslaß 18 gelangen zu lassen.1 to 4 and the stirrer mills shown in FIGS. 6 to 11 are intended to be operated with auxiliary grinding bodies 32, the stirrer mill shown in FIG. 5 has stirring elements 26 in the form toothed dispersing disks, which enable operation without auxiliary grinding bodies. The separating device 16 is designed as in FIGS. 3 and 4, but according to FIG. 5 it only has the task of retaining coarse regrind particles and only allowing processed regrind to reach the regrind outlet 18.

Die Rührwelle 12 ist in allen dargestellten Beispielen fliegend gelagert; eine Lagerung 52 und Wellendichtung 54 ist also nur, wie angedeutet, an einem Ende des Mahlbehälters 10 angeordnet. An diesem Ende oder in dessen Nähe ist ein Antrieb üblicher Bauart mit der Rührwelle 12 gekuppelt oder kuppelbar. Die Trennvorrichtung 16 ist bei jeder der in Fig. 1 bis 5 sowie in Fig. 7 bis 11 dargestellten Rührwerksmühlen in der von Antrieb und Lagerung 52 entfernten Hälfte des Mahlbehälters 10 angeordnet.The agitator shaft 12 is overhung in all the examples shown; A bearing 52 and shaft seal 54 is therefore only, as indicated, arranged at one end of the grinding container 10. At this end or in the vicinity thereof, a drive of conventional design is coupled or can be coupled to the agitator shaft 12. The separating device 16 is arranged in each of the agitator mills shown in FIGS. 1 to 5 and in FIGS. 7 to 11 in the half of the grinding container 10 remote from the drive and bearing 52.

Bei der in Fig. 6 dargestellten stehenden Rührwerksmühle ist die Trennvorrichtung 16 hingegen in der antriebsseitigen Hälfte des Mahlbehälters 10 angeordnet und mit dem Mahlgutauslaß 18 über eine Austragkammer 56 verbunden, die an die Wellendichtung 54 angrenzt. Die Rührelemente 26 sind dementsprechend an oder in der Nähe des freien Endes der Rührwelle 12 befestigt.In the standing agitator mill shown in FIG. 6, on the other hand, the separating device 16 is arranged in the drive-side half of the grinding container 10 and connected to the grinding material outlet 18 via a discharge chamber 56 which adjoins the shaft seal 54. The stirring elements 26 are accordingly attached to or in the vicinity of the free end of the stirring shaft 12.

Bei der in Fig. 7 dargestellten Rührwerksmühle ist die Rührwelle 12 nur im Bereich der Lagerung 52 und Wellendichtung 54 bishin zum Anfang der Einlaßzone 22 schlank; sie hat hier einen Durchmesser in der Größenordnung von einem Viertel bis ein Drittel des Innendurchmessers des Mahlbehälters 10. In geringem Abstand axial innerhalb der Wellendichtung 54 beginnt ein zur Rührwelle 12 gehörender Konus 58, der mit einer komplementär konisch geformten inneren Stirnwand 60 des Mahlbehälters 10 einen kegelförmigen Reibspalt 62 begrenzt. In einem radial inneren Bereich des kegelförmigen Reibspalts 64, nahe der Wellendichtung 54, mündet der Mahlguteinlaß 14. An den kegelförmigen Reibspalt 62 schließt sich ein zylindrischer Reibspalt 64 von ungefähr gleicher Breite an, der sich bis zum Ende der Einlaßzone 22 erstreckt. Das Mahlgut 30 wird in den Reibspalten 62 und 64 durch Reibung der diese Reibspalte begrenzenden Wände des Mahlbehälters 10 und der Rührwelle 12 aktiviert. In der Trennzone 24, rings um die Trennvorrichtung 16, hat die Rührwelle 12 einen Außendurchmesser, der etwas kleiner ist als der größte Durchmesser des Konus 58.In the agitator mill shown in FIG. 7, the agitator shaft 12 is slim only in the area of the bearing 52 and shaft seal 54 up to the beginning of the inlet zone 22; here it has a diameter of the order of a quarter to a third of the inside diameter of the grinding container 10. At a short distance axially inside the shaft seal 54, a cone 58 belonging to the agitator shaft 12 begins, which has a complementarily conical inner end wall 60 of the grinding container 10 conical friction gap 62 limited. In a radially inner one The region of the conical friction gap 64, near the shaft seal 54, opens the grist inlet 14. The conical friction gap 62 is followed by a cylindrical friction gap 64 of approximately the same width, which extends to the end of the inlet zone 22. The ground material 30 is activated in the friction gaps 62 and 64 by friction between the walls of the grinding container 10 and the agitator shaft 12 that delimit these friction gaps. In the separation zone 24, around the separation device 16, the agitator shaft 12 has an outer diameter that is slightly smaller than the largest diameter of the cone 58.

Fig. 8 stimmt mit Fig. 7 darin überein, daß der Außendurchmesser der Rührwelle 12 in geringem Abstand axial innerhalb der Wellendichtung 54 stark zunimmt. In einem Hauptteil der Einlaßzone 22 und in der gesamten Trennzone 24 hat die Rührwelle 12 einen Außendurchmesser, der etwa zwei Drittel des Innendurchmessers des Mahlbehälters 10 beträgt. In der Einlaßzone 22 und in der Trennzone 24 trägt die Rührwelle 12 Rührelemente 26 in Gestalt verhältnismäßig kurzer radialer Stifte. Gegenelemente 40, ebenfalls in Gestalt kurzer radialer, jedoch an der Innenwand des Mahlbehälters 10 befestigter Stifte, sind nur in der Einlaßzone 22 vorhanden; die gesamte Trennzone 24 rings um die Trennvorrichtung 16 ist von solchen Gegenelementen 40 frei.Fig. 8 agrees with Fig. 7 in that the outer diameter of the agitator shaft 12 increases axially within the shaft seal 54 at a short distance. In a main part of the inlet zone 22 and in the entire separation zone 24, the stirring shaft 12 has an outer diameter which is approximately two thirds of the inner diameter of the grinding container 10. In the inlet zone 22 and in the separation zone 24, the stirring shaft 12 carries stirring elements 26 in the form of relatively short radial pins. Counter-elements 40, also in the form of short radial pins, but attached to the inner wall of the grinding container 10, are only present in the inlet zone 22; the entire separation zone 24 around the separation device 16 is free of such counter-elements 40.

Die Rührwerksmühle gemäß Fig. 9 entspricht der in Fig. 7 dargestellten in der Gestaltung des Konus 58 und der inneren Stirnwand 60 des Mahlbehälters 10; somit sind auch hier ein kegelförmiger Reibspalt 62 und ein zylindrischer Reibspalt 64 vorhanden. Der zylindrische Reibspalt 64 ist jedoch sehr viel kürzer, da der Konus 58 mit einem in axialer Richtung schmalen Bund 66 endet und unmittelbar dahinter, gemäß Fig. 9 rechts davon, der Käfig 25 beginnt, dessen Außendurchmesser erheblich kleiner ist als derjenige des Bundes 66. Die Länge des Käfigs 25, und somit der Trennzone 24, beträgt annähernd drei Viertel der Länge des Mahlraums 20. Der Käfig 25 ist mit stiftförmigen Rührelementen 28 besetzt, zwischen die am Mahlbehälter 10 befestigte, ebenfalls stiftförmige Gegenelemente 40 radial nach innen ragen. Infolgendessen werden Mahlgut 30 und Mahlhilfskörper 32 in der Trennzone 24 verhältnismäßig stark aktiviert; die so aktivierten Mahlhilfskörper 32 sind jedoch durch den Bund 66 mit Sicherheit daran gehindert, in den Bereich des Mahlguteinlasses 14 zu gelangen. Dieser ist infolgedessen gegen Verschleiß besonders gut geschützt.The agitator mill according to FIG. 9 corresponds to that shown in FIG. 7 in the design of the cone 58 and the inner end wall 60 of the grinding container 10; thus a conical friction gap 62 and a cylindrical friction gap 64 are also present here. The cylindrical friction gap 64 is, however, much shorter since the cone 58 ends with a collar 66 which is narrow in the axial direction and the cage 25 begins immediately behind it, to the right of this in accordance with FIG. 9. whose outer diameter is considerably smaller than that of the collar 66. The length of the cage 25, and thus the separation zone 24, is approximately three quarters of the length of the grinding chamber 20. The cage 25 is equipped with pin-shaped stirring elements 28, between those fastened to the grinding container 10, pin-shaped counter-elements 40 also project radially inwards. As a result, regrind 30 and auxiliary grinding body 32 are relatively strongly activated in the separation zone 24; the auxiliary grinding bodies 32 activated in this way are, however, reliably prevented by the collar 66 from entering the region of the grinding material inlet 14. As a result, it is particularly well protected against wear.

Gemäß Fig. 10 ist der Käfig 25, ausgehend von seinem offenen freien Ende, in drei Bereiche unterteilt, die sich in axialer Richtung aneinander anschließen, nämlich einen in der Nähe des offenen Käfigendes beginnenden Bereich 66, der mit achsparallelen, radial durchgehenden Schlitzen 34 versehen ist, einen geschlossenen mittleren Bereich 68, der von solchen Schlitzen vollständig frei ist und einen vom offenen Käfigende entfernten Bereich 70, in dem wiederum radial durchgehende achsparallele Schlitze 34 vorgesehen sind. Der geschlossene mittlere Bereich 68 des Käfigs 25 ist gemäß Fig. 1 ungefähr halb so lang wie die Trennzone 24.10, the cage 25, starting from its open free end, is divided into three areas which adjoin one another in the axial direction, namely an area 66 starting near the open end of the cage and provided with axially parallel, radially continuous slots 34 is a closed central region 68 which is completely free of such slots and a region 70 which is distant from the open end of the cage and in which radially continuous axially parallel slots 34 are again provided. 1, the closed central region 68 of the cage 25 is approximately half as long as the separation zone 24.

Gemäß Fig. 11 ist der Käfig 25 nicht nur in seinem mittleren Bereich 68, sondern auch in seinem dem offenen Käfigende benachbarten Bereich vollständig geschlossen; radial durchgehende, achsparallele Schlitze 34 oder andere Öffnungen, durch die Mahlhilfskörper 32 aus dem Käfig 25 austreten können, sind nur in dem vom offenen Käfigende entfernten Bereich 70 angeordnet, der sich rings um den Endbereich 72 der Trennvorrichtung 16 erstreckt.11, the cage 25 is completely closed not only in its central region 68 but also in its region adjacent to the open end of the cage; Radially continuous, axially parallel slots 34 or other openings through which grinding aid bodies 32 can exit the cage 25 are arranged only in the region 70 which is distant from the open end of the cage and extends around the end region 72 of the separating device 16.

Mit den in Fig. 10 und 11 dargestellten Ausgestaltungen des Käfigs 25 gelingt es, die Gleichmäßigkeit der Umströmung der verhältnismäßig langen und großflächigen Trennvorrichtung 16 zu verbessern und dadurch die Zerkleinerungsleistung je Zeiteinheit noch weiter zu steigern. Mahlgut 30 und Mahlhilfskörper 32 sind gehindert, den Käfig 25 in seinem mittleren Bereich radial zu durchströmen. Dort kann somit nur eine von radialen Komponenten im wesentlichen freie Strömung stattfinden. Es hat sich herausgestellt, daß gerade dadurch Verstopfungen im Ringraum 38 zwischen der Trennvorrichtung 16 und der Innenwand des Käfigs 25 vermieden werden und die Leistungsfähigkeit der Trennvorrichtung auf deren gesamter Länge unter allen üblichen Betriebsbedingungen weitestgehend ausgenützt wird.With the embodiments of the cage 25 shown in FIGS. 10 and 11, it is possible to improve the uniformity of the flow around the relatively long and large-area separating device 16 and thereby to further increase the size reduction per unit time. Grist 30 and auxiliary grinding body 32 are prevented from flowing radially through the cage 25 in its central region. Only a flow that is essentially free of radial components can therefore take place there. It has been found that blockages in the annular space 38 between the separating device 16 and the inner wall of the cage 25 are avoided in this way and that the performance of the separating device over its entire length is largely utilized under all normal operating conditions.

Claims (13)

  1. Agitator mill comprising a grinding container (10) and an agitating shaft (12) arranged rotatably therein which together define a grinding space (20), an inlet (14) for the material to be ground, a cage (25) which as constituent of the agitating shaft (12) rotates with the latter and is open at one end, and a separating means (16) which is arranged in the cage (25) and retains unprocessed material (30) and possibly grinding auxiliary bodies (32) contained in the grinding space (20) but allows processed material (30) to flow off to a material outlet (18), the grinding space (20) being divided into an inlet zone (22) which follows the material inlet (14) and is axially traversed at least over a substantial part of its length by the agitating shaft (12) and a separating zone (24) which follows the inlet zone (22) in the axial direction and is arranged around the cage (25), characterized in that the separating zone (24) extends over 40 to 80 % of the total length of the grinding space (20) and the separating means (16) has an effective area with a magnitude at least 20 % of the internal surface of the grinding container (10) defining the grinding space (20).
  2. Agitator mill according to claim 1,
    characterized in that the separating means (16) has an effective area having a magnitude which is 25 to 50 % of the internal surface of the grinding container (10) defining the grinding space (20).
  3. Agitator mill according to claim 1 or 2,
    characterized in that the grinding container (10) and the agitating shaft (12) are formed in such a manner that within the inlet zone (22) at least 90 % and within the separating zone (24) at the most 10 % of the total drive power of the agitating shaft (12) is introduced into the material (30) to be ground.
  4. Agitator mill according to any one claims 1 to 3 of which the agitating shaft (12) carries agitating elements (26) with which counter elements (40) secured to the grinding container (10) are associated, characterized in that the counter elements (40) are arranged solely in the inlet zone (22).
  5. Agitator mill according to any one of claims 1 to 3, of which the agitating shaft (12) carries agitating elements (26),
    characterized in that the agitating elements (26) are arranged solely in the inlet zone (22).
  6. Agitator mill according to any one of claims 1 to 5,
    characterized in that the diameter of the agitating shaft (12) in the inlet zone (22) near the material inlet (14) is considerably smaller than in the separating zone (24).
  7. Agitator mill according to claim 6,
    characterized in that the diameter of the agitating shaft (12) increases gradually over at least a part of the length of the inlet zone (22) in the direction of the separating zone (24) to at least twice the smallest diameter which the agitating shaft (12) has in the inlet zone (22).
  8. Agitator mill according to claim 6 or 7,
    characterized in that the agitating shaft (12) comprises a smooth cone (58) in the inlet zone (22).
  9. Agitator mill according to claim 8,
    characterized in that the cone (58) is directly adjacent the material inlet (14).
  10. Agitator mill according to any one claims 1 to 9,
    characterized in that the agitating shaft (12) comprises in an end region of the inlet zone (22) near the separating zone (24) a collar (66) having a diameter which is greater than the diameter of the cage (25).
  11. Agitator mill according to any one of claims 1 to 10,
    characterized in that the cage (25) is closed in a centre region (68) which extends over at least a quarter of the total length of the separating zone (24).
  12. Agitator mill according to claim 11,
    characterized in that the closed region (68) of the cage (25) extends over a third to two thirds of the total length of the separating zone (24).
  13. Agitator mill according to claim 12,
    characterized in that the cage (25) is radially outwardly open only around an end region (72) of the separating means (16) remote from the open end of the cage (25).
EP89122340A 1988-12-30 1989-12-04 Agitator mill with a separating device in a rotating cage Expired - Lifetime EP0376001B1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE3844380 1988-12-30
DE19883844380 DE3844380C1 (en) 1988-12-30 1988-12-30 Agitator mill with separating device in a rotating cage
DE3938171A DE3938171C1 (en) 1988-12-30 1989-11-16
DE3938171 1989-11-16

Publications (2)

Publication Number Publication Date
EP0376001A1 EP0376001A1 (en) 1990-07-04
EP0376001B1 true EP0376001B1 (en) 1993-04-28

Family

ID=25875826

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89122340A Expired - Lifetime EP0376001B1 (en) 1988-12-30 1989-12-04 Agitator mill with a separating device in a rotating cage

Country Status (4)

Country Link
EP (1) EP0376001B1 (en)
JP (1) JP2680738B2 (en)
DE (2) DE3938171C1 (en)
WO (1) WO1990007378A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2744212C2 (en) * 2017-01-30 2021-03-03 Неч-Файнмальтехник Гмбх Bead mill

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5080293A (en) * 1990-10-15 1992-01-14 Union Process, Inc. Continuous wet grinding system
US5199656A (en) * 1990-10-15 1993-04-06 Union Process, Inc. Continuous wet grinding system
DE19510807C2 (en) * 1994-03-24 1997-04-17 Netzsch Erich Holding Agitator mill
DE4432198A1 (en) * 1994-09-09 1996-03-14 Evv Vermoegensverwaltungs Gmbh Agitator mill
DE19538476C2 (en) * 1995-10-16 1997-09-11 Netzsch Erich Holding Device for producing a pasty suspension
DE19819967B4 (en) * 1998-05-05 2007-04-26 BüHLER GMBH agitating mill
JP2006205136A (en) * 2005-01-31 2006-08-10 Tdk Corp Disperser
JP4684000B2 (en) * 2005-05-11 2011-05-18 アシザワ・ファインテック株式会社 Medium stirring type crusher
JP4741931B2 (en) 2005-05-17 2011-08-10 アシザワ・ファインテック株式会社 Circulation type media stirring mill
JP4583387B2 (en) * 2007-01-30 2010-11-17 オリバー イー バトレ ソシエダッド アノニマ Vertical stirring pulverizer
DE102010049827A1 (en) * 2010-10-27 2012-05-03 Netzsch-Feinmahltechnik Gmbh stirred ball mill
EP2999543B1 (en) 2013-05-21 2023-03-15 FLSmidth A/S Methods and apparatus for the continuous monitoring of wear in grinding circuits
DE102013021757A1 (en) * 2013-12-20 2015-06-25 Netzsch Trockenmahltechnik Gmbh Machine with floating rotor
US10493464B2 (en) 2014-12-18 2019-12-03 Aaron Engineered Process Equipment, Inc. Rotary mill
US10086379B2 (en) 2015-02-27 2018-10-02 Aaron Engineered Process Equipment, Inc. Rotary mill
EP3283204B1 (en) 2015-04-17 2020-12-23 Bühler AG Method and device for mixing, in particular for dispersion
JP6423988B2 (en) * 2016-01-28 2018-11-14 株式会社広島メタル＆マシナリー Stirring mill and dispersion method of particles in slurry
JP7378253B2 (en) * 2019-09-18 2023-11-13 日本コークス工業株式会社 Grinding method
DE102021123408A1 (en) * 2021-09-09 2023-03-09 Netzsch-Feinmahltechnik Gmbh agitator mill

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3172609A (en) * 1960-11-03 1965-03-09 Kaiser Aluminium Chem Corp Apparatus for disintegrating aggregates of solid material
DE1184188B (en) * 1961-06-21 1964-12-23 Draiswerke Gmbh Agitator mill for the production of solid dispersions
DE3345680A1 (en) * 1983-12-16 1985-06-20 Gebrüder Netzsch, Maschinenfabrik GmbH & Co, 8672 Selb AGITATOR MILL
DE3844380C1 (en) * 1988-12-30 1990-01-18 Erich Netzsch Gmbh & Co Holding Kg, 8672 Selb, De Agitator mill with separating device in a rotating cage

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2744212C2 (en) * 2017-01-30 2021-03-03 Неч-Файнмальтехник Гмбх Bead mill

Also Published As

Publication number Publication date
DE3938171C1 (en) 1991-01-03
EP0376001A1 (en) 1990-07-04
DE58904209D1 (en) 1993-06-03
JP2680738B2 (en) 1997-11-19
WO1990007378A1 (en) 1990-07-12
JPH03503025A (en) 1991-07-11

Similar Documents

Publication Publication Date Title
EP0376001B1 (en) Agitator mill with a separating device in a rotating cage
DE102018123096B4 (en) Agitator ball mill and method for operating an agitator ball mill
EP2178643B1 (en) Stirrer mill
DE4432200C1 (en) Agitator mill
EP3311922B1 (en) Agitator ball mill
WO1985002559A1 (en) Mixing mill
DE3709623C2 (en)
DE19727663B4 (en) comminution device
EP0529434A1 (en) Agitator ball mill and method of operation thereof
EP1534435B1 (en) Ball mill provided with an agitator
EP0913200B1 (en) Agitator mill
DE102004050003B4 (en) Device for crushing feed with cooling air duct
DE3844380C1 (en) Agitator mill with separating device in a rotating cage
DE4448043B4 (en) agitating mill
DE3308390C2 (en) Grinding grinder
DE4217316A1 (en) DEVICE FOR GRINDING RUBBER
EP0665059B1 (en) Agitator ball mill
EP0640397B1 (en) Agitator mill
DE4213608C2 (en) Device for crushing rubber chunks
DE4216939C2 (en) Agitator mill with dynamic grinding media separation
EP0260604B1 (en) Agitator mill
DE102021101527B4 (en) agitator mill
DE3927076C2 (en)
CH679461A5 (en) Stirrer type grinding mill
DE9420964U1 (en) Agitator mill with separator to retain grinding beads

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE CH DE FR GB LI

17P Request for examination filed

Effective date: 19900523

17Q First examination report despatched

Effective date: 19911104

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE CH DE FR GB LI

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19930405

REF Corresponds to:

Ref document number: 58904209

Country of ref document: DE

Date of ref document: 19930603

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19951211

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19970829

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20081223

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 20081218

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20081230

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20081217

Year of fee payment: 20

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20091203

BE20 Be: patent expired

Owner name: ERICH *NETZSCH G.M.B.H. & CO. HOLDING K.G.

Effective date: 20091204

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20091203