JPH03503025A - Stirred mill with separation means in the rotating cage - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Stirring Mill with Separation Means in a Rotating Cage The present invention comprises a grinding vessel and a rotating cage inside the grinding vessel. It is equipped with a rotatably arranged stirring shaft, which limits the grinding space and further increases the an inlet for the material to be crushed and a cage that rotates with the stirring shaft as part of the stirring shaft. and separation means disposed within the cage, the separation means separating the untreated material and the separation means. and, if necessary, the milling auxiliary media and flow the processed material to the material outlet. In addition, the crushing space is arranged adjacent to the material inlet. and a stirring shaft is arranged in the axial direction over at least a large part of its entire length. an inlet zone and a separation arranged around the cage periphery axially adjacent to the inlet zone This relates to a stirring mill that is divided into zones.

Known stirred mills of the type mentioned above (see European Patent No. 0146852B1) , the separation zone is an arrangement extending over a maximum of 25% of the total length of the grinding space. at least 75% of its total length is occupied by the entrance zone. The effective area of the zero separation means is generally determined by the area inside the grinding vessel which limits the grinding space. It is said to be 5 to 10% of the area. As a result, the separation means are capable of discharging the material to be crushed. considerably inhibits the production of Therefore, the speed of material flow in the axial direction of the grinding vessel The grain content is relatively small and each individual particle of the material to be crushed is separated by a material inlet and separation means. There is a high probability that it will be gradually reduced to the desired size over a long path between. However, the known mill The throughput per unit time cannot be said to be very high for the given overall dimensions of stomach. This is because a single process of material through the grinding space of an agitated mill requires less grinding. To achieve a sufficient material must be transferred repeatedly between the supply container and the grinding space. This is obvious from the necessity of reciprocating suction.

The problem underlying the present invention is to significantly improve the crushing performance per unit time. We propose a stirred mill that enables particularly uniform grinding of the material to be ground. It's there.

In order to solve this problem, the present invention provides a stirred mill of the type mentioned at the outset. The separation zone extends over 40-80% of the total length of the grinding space and The effective area of the separation means can be reduced by reducing the internal area of the crushing container (which limits the crushing space). 20%.

In this specification, the effective area of the separation means is defined as the area between the sieve mesh or the separation ring. means the surface area of the separating means provided with an annular gap located at .

The stirred mill according to the present invention has a relatively long separation zone and a relatively large effective area of the separation means. Due to the large size of the target, it can pass through relatively quickly, thus reducing the need for crushing. Each individual particle of the material being ground is properly ground in one pass through the grinding space. The probability of it happening is very low. Therefore, from a statistical average point of view, the individual particles of the material , in order to be ground to the desired particle size in the known stirred mill described in the preamble. It is necessary to pass through the grinding space much more frequently. Despite that, According to the stirred mill of the invention, it is considerably more The surprising effect of achieving high crushing power was confirmed. crushing The uniformity of can be further improved. Average residence time of individual particles in a stirred mill is shorter, so the risk of damage to the material due to overheating is substantially less than in the prior art. few.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Figures 1 to 11 1 and 2 respectively show the stirring mill in joint cross section.

Each of the illustrated stirring mills is a substantially cylindrical grinding mill with a stirring shaft 12 coaxially attached therein. It comprises a container 10, an inlet 14 for the material to be crushed, and separation means 16, the separation means having a A material outlet 18 is arranged on the downstream side. The crushing container 10 and the stirring shaft 12 A grinding chamber, that is, a grinding space 20 is formed between the In the mill, an inlet zone shall include a population zone 22 and a separation zone 24. 1 and 7 to 11). , or axially connected to the inlet (FIGS. 2-6). separation zone 24 arranged around the cage 25 axially connected to the inlet zone 22; is formed on the agitation shaft 12 and has at least a substantially cylindrical shape to form the separation means 16. The structure is such that it is surrounded and opened at one end. Note that the length of the separation zone 24 is Match the length of the cage 25.

The separating means 16 may be constituted by a plurality of individual separating rings or by a sieve mesh. In all the illustrated embodiments, it is formed at least approximately cylindrical. 0 to match the effective length with the length of the cage 25 and therefore with the length of the separation zone 24. In all the embodiments shown, the length of the separating means 16 measured in the axial direction of the stirring shaft 12 is , about 172 of the total length of the grinding space 20 (Figs. 1 to 8, 10 and 11) Figure) to approximately 273 (Figure 9), which plays a decisive role in the throughput. The outer diameter of the operating surface of the stage 16 is set slightly smaller than the inner diameter of the cage 25. separated hands The product of the length and diameter of the working surface of stage 16 is the product of the length and internal diameter of grinding vessel 10. Approximately 20-25%.

In the stirring mills shown in FIGS. 1 to 5 and 7 to 11, the stirring shaft 12 is horizontal. It is placed horizontally. In contrast, Figure 6 shows a vertically placed stirring machine. This shows the

In the stirring mill shown in FIG. 1, the material inlet 14 is formed by a hole in the stirring shaft 12. Ru. In the region from the start to the end of the inlet zone 22, the stirring shaft 12 has a small diameter. That is, its outer diameter is about 1/4 to 1/3 of the inner diameter of the crushing container 10. Enter Towards the end of the mouth zone 22, the outer diameter of the stirring shaft 12 is approximately 2 times the inner diameter of the grinding container 10. 73: The stirring shaft 12 has its large diameter in the separation zone 24. The configuration is such that it is retained.

A stirring element 26 is supported by the region of the stirring shaft 12 arranged in the inlet zone 22 : In the embodiment of FIG. 1, the stirring element extends towards the cylindrical inner wall of the grinding vessel 10. formed by long radial bins. Stirring shaft 12 located within separation zone 24 A stirring element 28 is also supported by the cage 25 in the region of Formed by radial pins. As shown in FIG. 1, the grinding space 20 is Partially filled with material to be processed 30 and grinding auxiliary media 32.

The cage 25, in the embodiment of FIG. 1, comprises a slot 34 parallel to the axis; And, the zero separation means 16 is configured to be open at the end opposite to the material outlet 18. A cylindrical sieve arranged coaxially with the stirring shaft 12 and attached to the crushing container 10 Form. A packing body 36 coaxial with the separation means 16 is disposed inside the separation means 16, and this The packing has a relatively narrow gap between it and the separating means 16 that widens towards the outlet 18 of the material. The arrangement is such that the annular space 38 remains.

The material 30 to be crushed is primarily processed in the inlet zone 22 and In this case, the grinding support medium, that is, the auxiliary medium 32 is strongly activated by the long stirring element 26. be converted into Nevertheless, the material inlet 14 is relatively well protected. Because of this, many collisions occur with the crushing support medium 32 that moves at high speed. There is no risk of wear. The short stirring element 28 within the separation zone 24 substantially In this case, the function of avoiding or eliminating agglomeration of the crushing support medium 32 is fully exhibited. It is.

Material 30 mixed with grinding support media 32 is transferred from inlet zone 22 to separation zone 24 and flows through the open end of the stirring shaft 12 into its cage 25. Ke From the stage, the treated material 30 passes through a separating means 16 and an annular space 38. and flows to the material outlet 18.

In contrast, the grinding aid or grinding support medium 32 is passed through the slot 34. After being projected outward, the cycle repeats.

The stirring mill according to the embodiment of FIG. It differs from the one shown in FIG. There is. Further, an opposing element 4 is provided on the cylindrical inner wall in the inlet zone 22 of the crushing container 1o. 0 and these opposing elements are formed as radial pins between the stirring elements 260. It extends to just before the stirring shaft 12. Furthermore, a refrigerant flow path 42 is formed in the stirring shaft 12. : This flow path runs from the drive side of the stirring shaft 12 at the left end in the drawing to the inside of the packing body 36. In the embodiment shown in FIG. 2, the filling body is formed integrally with the stirring shaft 12 or Install on the stirring shaft. Although the separating means in the embodiment of FIG. 2 is also constituted by a sieve, the first Unlike in the figure, the sieve is adapted to rotate the separating means 16 together with the stirring shaft 12. , attached to the stirring shaft 12 instead of the crushing container 10.

In the embodiment of FIG. 3, the stirring element 26 is attached to the stirring shaft 12 in the inlet zone 22. formed by attached circular or non-circular discs. The separating means 16 includes a first It is attached to the grinding vessel 10 in the same way as in the figure, but in the example of FIG. With a zero separation zone 24 formed by a ring device with radial gears between In this case, the stirring shaft 12 is not provided with a stirring element; however, the cage 2 is installed around the separating means 16. 5, the slot 34 can accommodate various materials to be crushed. The material 30 and the grinding auxiliary medium 32 can be subjected to sufficient movement.

In particular, the embodiment shown in FIG. The fixed opposing element 40 is attached to the stirring vessel 10 between It differs from the one shown in Figure 3 in that it is formed by radial pins similarly to . As shown in FIG. 4, the stirring shaft 12 is provided with a solid shaft core 44, and on this core A disc-shaped stirring element 26, a spacer bush 46 disposed between the stirring elements, and a Then, the hollow shaft portion 48 supporting the cage 25 is attached.

The outer diameter profile shape of the stirring shaft 12 shown in FIG. 4 is the same as that shown in FIG. 3. deer However, the disk-shaped stirring element 26 located on the left side of FIG. A radial slot 50 is formed which corresponds to the counter element in the form of a ring. These slots are , with the shaft core 44 already installed in the grinding container 10, or with the shaft core 44 already installed in the grinding container 10, or Before inserting the stirrer 44 from the right side to the left side as shown in FIG. 6 to be able to fit onto the shaft core 44.

The stirred mills shown in Figures 1 to 4 and 6 to 11 use grinding auxiliary media. In contrast, the stirred mill shown in Figure 5 is A stirring element 26 formed as a dispersing disk with a grinding aid is provided to avoid the use of a grinding aid medium. The zero separation means 16, which allows for easy operation, is shown in FIGS. 3 and 4. , but in the example of Figure 5 retains the coarse particles of the material and is processed. It functions to allow only the material to reach the material outlet 1B.

In all the embodiments shown, the stirring shaft 12 is mounted in the form of a cantilever. , so the bearing 52 and shaft seal 54 are located at one end of the grinding vessel 10 as shown. It is located only in Connect a drive of normal configuration to or near this end. or can be combined. Each stirring shown in Figures 1 to 5 and Figures 7 to 11 In an agitated mill, the separating means 16 is a grinding vessel separate from the drive and the mount. Placed within 10 halves.

However, in the vertical stirring mill shown in FIG. 6, the separation means 16 is a discharge chamber located within the drive half of the container 10 and adjacent to the shaft seal 54; 56 to the material outlet 18.

Therefore, the stirring element 26 is attached at or near the free end of the stirring shaft 2.

In the stirred mill shown in FIG. 7, the stirring shaft 12 ends at the beginning of the inlet zone 22. The diameter is small only in the area of the bearing 52 and shaft seal 54. Its diameter is crushed It is approximately 1/4 to 1/3 of the inner diameter of the container 10. Slightly from the shaft seal 54 in the axial direction The conical portion 58 forming part of the stirring shaft 12 is started at a distance of The conical portion and the corresponding inner end wall of the crushing container 10 formed in a conical shape. Defining a more conical friction gap 62. The material population 14 is placed near the shaft seal 54. 0 conical friction opening into the radially inner region of the tangential conical friction gap 620 A cylindrical friction gap 64 of approximately the same width is connected to the gap 62, and this cylindrical friction The gap extends to the end of the entrance zone 22. The material 30 to be crushed is Friction with the walls of the grinding vessel and stirring shaft, which limits the friction gap 62.64, activated within the friction gap. Separation zone 24 around the separation means 16 The outer diameter of the stirring shaft 12 is set to be slightly smaller than the maximum diameter of the conical portion 58.

In the embodiment shown in FIG. 8, the outer diameter of the stirring shaft 12 is at a small axial distance from the shaft seal 54. This corresponds to the example in FIG. 7 in that it decreases significantly within the range. Entrance zone 2 2 and the entire separation zone 24, the outer diameter of the stirring shaft 12 is equal to or smaller than the grinding volume. It is approximately 2/3 of the inner diameter of the vessel 10. Inlet zone 22 and separation zone 24 The stirring shaft 12 is provided with a stirring element 26 consisting of a relatively short radial pin.

However, the opposing elements mounted on the inner wall of the grinding vessel as short radial pins as well 40 is arranged only in the inlet zone 22: such a counter element 40 16 is not arranged in the separation cylinder 24 around the periphery.

The stirred mill shown in FIG. In accounting, this corresponds to the example shown in FIG.

That is, also in this example, the conical friction gap 62 and the cylindrical friction gap 64 is provided. However, the conical portion 58 terminates in an axially narrow collar 66. At the same time, there is a cage with an outer diameter smaller than the collar 66 immediately after that, that is, on the right side in FIG. By connecting the groove 25, the cylindrical friction gap 64 is made very short. Ru. The length of the cage 25 and therefore the length of the separation zone 24 is the same as that of the grinding space 20. It should be about 3/4 of the length of. Attaching a bottle-shaped stirring element 28 to the cage 25 and , A bottle-shaped opposing element 40 is similarly attached to the crushing vessel 0 between these, and the radial direction Protrude inward. As a result, material 30 and grinding aid medium 32 are relatively strongly activated.

However, the activated grinding auxiliary medium 32 is reliably controlled by the collar 66. It is blocked and does not reach the area of material population 14. Therefore, the material inlet is especially It is effectively protected from wear.

In the embodiment shown in FIG. 10, the cage 25 is moved in the axial direction from its free end Starting from the three interconnecting regions, i.e. close to the open cage end, a region 66 provided with a radially continuous slot 34 parallel to the axial direction; A closed central region 68 with no such slots and a closed central region 68 separated from the open cage ends. A region 7 located at a diagonal position and provided with radially continuous slots 34 0 and 0. As in FIG. 1, the length of the closed central region 68 of the cage 25 The length is approximately 172 mm of the length of the separation zone 24.

In the embodiment shown in FIG. It is also completely closed in the area adjacent to the released cage end. Half parallel to the axial direction An opening, such as a radially continuous slot 34, allows the grinding support media 32 to pass through the cage 2. 5, but only in the area 70 away from the open cage end. and extend around the end region 72 of the separation means 16.

According to the configuration of the cage 25 shown in FIGS. 10 and 11, the cage 25 is relatively long and has a large area. improves the uniformity of the flow around the separation means, thereby reducing the amount of milling per unit time. It becomes possible to further increase the power. The material 30 and the grinding support media 32 are radial flow is blocked in the central region of the cage. in its central area can produce only flows that do not contain a radial component. the result , the blockage in the annular space 38 between the separating means 16 and the inner wall of the cage 25 is prevented. can be prevented, and under any normal operating conditions, the separation means can be This makes it possible to achieve maximum efficiency.

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Claims (1)

[Claims] 1. A grinding container (10) and a stirring shaft (12) rotatably arranged inside the grinding container (10). These limit the grinding space (20) and also allow the material to be ground to be an inlet (14) and a cage (2) rotating with the stirring shaft as part of the stirring shaft (12); 5) and separating means (16) disposed within the cage (25), said separating means holds unprocessed material (30) and optional grinding aid media (32) In addition, the treated material (30) is configured to be able to flow out to the material outlet (18). , furthermore, a grinding space (20) is arranged adjacent to the material inlet (14). In addition, a stirring shaft (12) is disposed in the axial direction over at least a large portion of its entire length. a cage (22) axially adjacent the inlet zone (22); 25) and a separation zone (24) arranged around the stirred mill. The separation zone (24) extends over 40-80% of the total length of the grinding space (20). and extend the effective area of the separation means (16) to the crushing space (2). 0) is at least 20% of the internal area of the crushing container (10). A stirring mill with a characteristic. 2. A stirred mill according to claim 1, wherein the effective area of the separating means (16) is 25 to 50% of the internal area of the crushing container (10) which limits the crushing space (20). A stirring mill characterized by: 3. The stirring mill according to claim 1 or 2, wherein the grinding container (10) and the stirring At least 90% of the total driving power of the stirring shaft (12) In the zone (22) and up to 10% in the separation zone (24) the material to be crushed A stirred mill characterized in that it is configured to be introduced into a feedstock (30). 4. The stirring mill according to any one of claims 1 to 3, wherein the stirring shaft (12) The stirring element (26) is supported by a counter element (4) in relation to the stirring element. 0) attached to the crushing container (10), the opposing element (40) is exclusively Stirring mill, characterized in that it is arranged in the inlet zone (22). 5. The stirring mill according to any one of claims 1 to 3, wherein the stirring shaft (12) In those that support the stirring element (26) more, the stirring element (26) is exclusively included. Stirring mill, characterized in that it is arranged in the mouth zone (22). 6. Stirred mill according to any one of claims 1 to 5, in which the material inlet (14) The diameter of the stirring shaft (12) in the inlet zone (22) adjacent to the separation zone A stirring mill characterized in that the diameter is set considerably smaller than the diameter in (24). 7. A stirred mill according to claim 6, wherein the diameter of the stirring shaft (12) is adjusted to the diameter of the inlet zone. a stirring shaft in the inlet zone (22) over at least part of the length of the tube (22); gradually increasing in the direction of the separation zone (24) up to at least twice the minimum diameter of (12). A stirring mill characterized by the addition of additives. 8. The stirring mill according to claim 6 or 7, wherein the stirring shaft (12) has an inlet zone. A stirred mill characterized in that a smooth conical section (58) is provided within the tube (22). 9. Stirred mill according to claim 8, in which the conical portion (58) is connected to the material inlet (14). A stirring mill characterized in that it is located directly adjacent to. 10. The stirring mill according to any one of claims 1 to 9, wherein the stirring shaft (12) In the end area of the inlet zone (22) adjacent to the separation zone (24), the cage is It is characterized by having a collar (66) having a larger diameter than the diameter of (25). Stirring mill. 11. The stirred mill according to any one of claims 1 to 10, wherein the cage (25 ) is formed in a closed shape in a central region (68), which central region is defined by a separation zone (2 4) A stirred mill characterized in that it extends over at least 1/4 of the total length of the mill. 12. Stirred mill according to claim 11, in which the closed area (68) of the cage (25) extending over 1/3 to 2/3 of the total length of the separation zone (24). Stirring mill. 13. Stirred mill according to claim 12, in which the cage (25) is exclusively a cage. radially outwardly around an end region (72) remote from the open end of (25); A stirring mill characterized by being formed into an open shape.