EP1909962B1 - Knife mill - Google Patents

Abstract

The invention relates to a knife mill which comprises an annular sieve (40) in which a knife rotor (74) is driven to rotate therein. In order to increase the effectiveness of such a knife mill (10), especially for grinding spices, the annular sieve (40) is also driven to rotate and/or the central knife rotor (74) is surrounded by a plurality of knife sets (22-24). The annular sieve ring (40) and/or the knife sets (22-24) can be driven so as to rotate in a direction opposite to that of the knife rotor (74) but can also be driven in the same direction of rotation but at different rotational speeds.

Description

The invention relates to a knife cutting mill, in particular for grinding spices, with a sieving ring, in which a knife rotor is driven in rotation.

Such a knife cutting mill with the superordinate features of claim 1 is for example from the U.S. Patent 6,585,178 known. This vertical type with a driven blade rotor that rotates within a sieve ring has been known for decades. The material to be ground is supplied from above, is crushed and ground by the knife rotor, and then leave the grinding chamber mostly in the radial direction via the sieve openings. A disadvantage of such knife cutting mills is often the heat generated by friction, which can damage delicate regrind, such as spices. Also, in such knife cutting mills often a long grinding time is required so that spices can be additionally damaged.

The DE 26 13 455 A1 describes a knife cutting mill with a sieve ring (4) in which a blade rotor (3) is driven in rotation, wherein the sieve ring is also driven in rotation according to the preamble of claim 1.

The EP-A-0 163 084 describes a knife cutting mill with a Siebring (6) in which a blade rotor (23) is driven in rotation, wherein the central blade rotor (23) of a plurality of blade sets (17) is surrounded.

The DE 88 04 662 U1 shows a knife cutting mill with a sieve ring (1) in which a blade rotor (4) is driven in rotation, wherein a blade rotor of several sets of blades (rotors 4) is surrounded.

Accordingly, the invention has for its object to provide a knife cutting mill of the type mentioned, which avoids the above disadvantages and allows a short grinding time.

This object is achieved by a knife cutting mill according to the features of claim 1. Preferred developments of the invention are subject of the dependent claims.

The proposed knife cutting mill is characterized by a particularly high efficiency. In particular, a shortening of the grinding time is achieved by the Gegenläufige.Rotation (or in the same direction) of the Siebringes in addition to the blade rotor, which is important for the preferred embodiment for the grinding of spices. As a result, a slight damage to the flavorings is achieved, which has an overall positive effect on the quality. Alternatively or additionally, a plurality of planet blade sets may be provided between the central blade rotor and the screen ring, which are driven in rotation and thus further improve comminution.

It should be noted that the proposed knife cutting mill is suitable for various materials. In this case, several sets of blades can be provided. These knife sets enable effective grinding in the knife cutting mill. Of particular importance in the realization of the knife-edge mill is that a quick conversion of the knife cutting mill is made possible in order to adapt to the respective ground material in a simple manner. The essential advantage of this granulator is that no heat is generated during the milling and thus the quality of the heat-sensitive products is not impaired, e.g. the aroma of spices.

Fig. 1

eine Seitenansicht einer Messerschneidmühle für Gewürze;

Fig. 2

eine Darstellung der Messerschneidmühle gemäß Fig. 1 im angehobenen Zustand; und

Fig. 3

eine vergrößerte Unteransicht auf einen Vorschneidering.

Fig. 4

eine abgewandelte Ausführungsform mit mehreren Messersätzen; und

Fig. 5

eine Draufsicht auf die Messersätze gemäß Fig. 4.

Hereinafter, an embodiment will be explained and described in more detail with reference to the accompanying drawings. Herein show:

Fig. 1

a side view of a knife cutting mill for spices;

Fig. 2

an illustration of the knife cutting mill according to Fig. 1 in the raised state; and

Fig. 3

an enlarged bottom view of a pre-cutting ring.

Fig. 4

a modified embodiment with multiple sets of blades; and

Fig. 5

a plan view of the blade sets according to Fig. 4 ,

In Fig. 1 an embodiment of a knife cutting mill 10 is shown. This knife-cutting mill 10 has a tubular housing 11 or interconnected housing parts, in which case the upper end side serves as an inlet 12 and the left side as an outlet 13 for the forwarding of the ground material. In this case, the inlet 12 to the housing 11 can be designed in adaptation to the material to be ground, in particular with respectively desired Zuführwinkein, passage cross sections, etc. This mill is suitable for grinding all granules in the spice, plastics and food industries, but also for minerals, rubber, rubber, or similar natural products.

The mill consists of generally two assemblies, which in Fig. 2 shown pulled apart, so with raised top, as required for example for the replacement of knives.

The lower part consists of a frame with a motor 102 for driving a plurality of horizontal blades in the housing 11, whereby a central blade rotor 74 is formed.

The upper part has an overhead motor 103, which has a shaft. 9 drives a round sieve ring 40. At the top of the sieve ring 40 are four openings 41 (see. Fig. 3 ) and there four knives 35 are attached as a pre-cutter to form a Vorschneidering 34. This one is in Fig. 3 across from Fig. 1 and 2 shown enlarged approximately twice. Immediately below a flat pre-screen 117 is attached and provided in turn below the Vorschneidemesser 35 slots, so that the pre-shredded granules can flow through. On the housing 11, in particular the lid 67, also standing to support the rotating Vorschneidemesser standing knife 118 may be attached to.

Attached to the sieve ring 40 is a strainer basket, which also rotates according to the invention so that the ground material (powder) is ejected more effectively out of the chamber. The drive motors 102 and 103 are powered by a frequency converter, so that these motors can be controlled continuously up to maximum speed, even during the run. Likewise, the direction of rotation from the left or right for each of the motors 102 and 103 is separately adjustable.

The material is to be filled through the inlet channel 12, which is fixed to the lid 67 of the housing 11, on the upper side of the mill. The shape of the inlet channel is rectangular here, but can also be designed round or elliptical as needed. The material is first processed by the upper pre-cutting ring 34, which is fixed to the upper shaft 9 by means of a screw 17. This upper Vorschneidering 34 is here with four identical blades 35 (see. Fig. 3 ) fitted. But it can also be provided with one, two or three knives. On the side part of the filling opening here a fixed knife 118 is attached to the cover 67, which is intended to prevent larger pieces of material failing by larger pieces of material, if necessary, are crushed by the pre-cutting ring 34. If necessary, a plurality of such knives 118 may be provided.

Below the upper pre-cutting ring 34 is a flat Vorsieb 117 with small incisions in front of the knife edge and with larger openings behind each knife blade attached. The hole pattern of the preliminary screen 117 may be round, square, triangular or elliptical and the size may vary between one or ten millimeters. Depending on the nature of the material to be processed, other hole pattern sizes can be used. For example, a hole pattern similar to the pre-cutting ring 34 may be used, as in FIG Fig. 3 is shown. This Vorsieb 117 is to prevent too fast falling through large pieces of material, which in turn depends on the inlet speed. In addition, labyrinth-like webs or grooves may be provided for this purpose in this cutting area.

After being processed by the pre-cutting ring 34, the partially comminuted material passes to lower knives 22, 23, 24 of the knife rotor 74, which are fastened to the lower shaft 65 by means of a screw. The first of these knives 22 is straight in the horizontal plane, the second 23 bent downwards and the third 24 is bent upwards. The angle at which the knife is bent depends on the material to be machined and can range between 0 ° and 30 °. There are numerous combinations of knives of this type. On the shaft 65 not all blades must be mounted. The knives can be oriented in the same direction or rotated 45 ° or 90 ° to each other. On these knives 22-24, the material is additionally comminuted with the cutters positioned so as to crush the material as well as to move it down and radially outwards. The resulting turbulences lead to additional ventilation and thus reduce the processing temperature. These knives 22-24 may be arranged planetary instead of one above the other also parallel to the central knife rotor 74, as shown in FIG Fig. 4 and 5 is shown.

Below these knives, a plate 26 is mounted with small central knives 27, which are also mounted on the lower shaft 65. On the plate 26 are thus either straight or upwardly curved central knife 27, which are mounted so that a separate attachment is not necessary. Depending on the nature of the material, this plate 26 can also be removed from the granulator 1 with the central knives 27. These knives 27 crush the material already through the knives 22 - 24 has passed, in addition, especially the proportion of material, which is closer to the shaft 65. The occurring turbulences lead to an additional ventilation.

Just below, another plate 47 is fastened with screws to the base plate 30 of the knife rotor 74. The angle of the upwardly bent blades 43, 44 depends on the type of material to be machined and can range from 0 ° to 45 ° (up to a maximum of 90 °). This results in numerous combinations of these Nachschneidemesser 43 and 44, which additionally comminute the material with the centrifugal force before exiting the granulator. These knives are e.g. alternately aligned with 70 ° and 90 ° angles. Each knife is here separately fastened because of the simpler maintenance. If necessary, the knives 43, 44 may also be connected to the plate 47. Each individual knife can be replaced and is fastened with screws on the underside of the base plate 30. These knives 43 and 44 additionally shred the material as they cut it once more and move it down and out. The resulting turbulence in turn lead to additional ventilation. Below the knife is another plate attached, which covers the screws and thus prevents shredded material from hanging on the knives 43 and 44.

Below the blades 43, 44 are vanes 53, which additionally strengthen the crushing of the finer material, with the tools mounted here pivoting (or rotating) about their own axis and aligning themselves with the centrifugal force to the position for cutting. For example, five knives can be used, the number can be changed more or less according to the application. The knives or tools are ground in such a way that they additionally reinforce the conveyance of the material to the outside in the lower part of the mill, and the resulting turbulences in turn promote the desired ventilation. The blades 53 are attached by means of screws below the base plate 30 of the knife rotor 74. They are after opening of the housing 11 (see. Fig.2 ) freely accessible and easily interchangeable.

Finally, the finished material passes through the interchangeable sieve ring 40. The hole pattern of the sieve ring 40 can be round, square, elliptical or triangular and the hole size can be between 1-10 mm, which can be varied as needed. The sieve ring 40 is attached to an upper ring 36 and to a lower ring 88 attached with appropriate brackets. The upper ring 36 is fastened to the upper pre-cutting ring 34 with screws. The distance between the two rings 36 and 88 secure round and Kantbolzen 42, which are fastened with screws. The material then passes through the annular gap S and the outlet channel 13 which is hinged to ensure better accessibility for cleaning.

The entire blade rotor 74 is located above a bottom plate 54, to which the housing 11 is fastened with screws. The bottom plate 54 is mounted on a frame plate 76A, on which the lower shaft 65 is mounted with ball bearings in a bracket 57, as well as lower V-belt pulleys 58 and 79. A V-belt 84 and the motor 102 serves to drive the entire lower knife rotor 74th

On the lid 67, a carrier 56 is provided for the upper motor 103 in a similar manner. This is connected to the shaft 9 and serves to drive the upper Vorschneiderings 34 and the associated Siebrings 40th

In Fig. 2 the partially open position of the mill 10 is shown, with the entire upper assembly (with the sieve ring 40) being raised from the housing 11 on spring-assisted guides. This assembly can still be completely pivoted about the axis A, as indicated by the arrow in the region of the motor 103, so that then the upper and lower assembly (with the blade rotor 74), for example, to change the knife 22 - 24 is optimally accessible , For larger cutting mills this lifting can also be supported by pneumatic or hydraulic cylinders.

In Fig. 3 is shown attached to the top of the rotating Siebrings 40 Vorschneidering 34. From this, the symmetrical arrangement of the four openings 41 and associated knife 35 can be seen. As indicated above, the number of blades 35 and / or apertures 41 or their course and size can be varied in adaptation to the material to be ground. The same applies to the size of the screen openings schematically shown here, in particular for the hole pattern of the sieve ring 40th

In Fig. 4 is a modified version of the mill 10 'shown in the continuation of the idea of using multiple sets of knives, these planets around the central knife rotor 74 are arranged. These knife sets 22, 22 ', 23, 23', 24, 24 '(see. Fig. 5 with 6 such sets of blades) are driven in rotation from below via a transfer case 104, preferably in the opposite direction to the direction of rotation of the central knife rotor 74; which is driven via the shaft 9 here from above. The blade sets 22-24 are driven by shafts W from below, these blades intervening in knife interstices of the central blade rotor 74 and also mesh with the respective adjacent blade sets.

In this case, the supplied grinding stock is crushed particularly intense before it exits via the sieve ring 40, which can stand still in this case, since the crushing is similar to the knives 43, 44 in the interaction of the individual sets of knives. This embodiment is particularly suitable for the comminution of rubber or scrap tires, which can be largely dispensed with by the turbulence in the housing 11 to a cooling, in particular to the use of otherwise conventional nitrogen cooling.

In Fig. 5 is a plan view of the here 6 sets of knives 22, 22 ', 23, 23', 24 and 24 'shown, planetary surround the central knife rotor 74, whose axis is aligned parallel to the upright axes or waves W. These knife sets run in rotation (see circulation circle U) with each other and in cooperation with the knives of the central knife rotor 74 just past the sieve ring 40, resulting in small dead volumes. These can be further reduced if more knife sets (eg 12) are used. Due to the considerable turbulence in the housing 11, however, a sticking of the ground material is avoided, although the sieve ring 40 can be fixed in this case. However, it can also be rotated by a pivot drive, for example by 60 ° about the vertical axis, as indicated by the arrow X, or as in Fig. 1 be formed circumferentially.

Claims (9)

1. Knife mill, in particular for milling spices, with a filter ring in which a knife rotor is rotationally driven, wherein the filter ring (40) is also rotationally driven and/or the central knife rotor (74) is surrounded by several cutting blades (22-24),
   characterised in that
   the bottom range of the knife rotor (74) has blades (53), which include tools at their outer range adapted to pivot to the filter ring (40) under centrifugal force.
2. Knife mill according to claim 1, characterised in that
   the filter ring (40) and/or the cutting blades (22 24) and the knife rotor (74) are driven in opposite directions.
3. Knife mill according to claim 1, characterised in that
   the filter ring (40) and/or the cutting blades (22 24) and the knife rotor (74) are driven with different rotational speeds in parallel.
4. Knife mill according to one of claims 1 to 3, characterised in that controllable motors (103, 102) are provided for driving the filter ring (40) and/or the cutting blades (22 - 24) as well as the knife rotor (74), in particular by means of a frequency inverter.
5. Knife mill according to one of claims 1 to 4, characterised in that the filter ring (40) includes a pre-cut ring (34) at its top.
6. Knife mill according to claim 5, characterised in that
   a pre-sieve (117) is arranged directly below the pre-cut ring (34).
7. Knife mill according to one of claims 1 to 6, characterised in that the cutting blades (22 - 24) are arranged around the central knife rotor (74) like planets, each with upright shafts (W).
8. Knife mill according to claim 7, characterised in that
   the cutting blades (22, 23, 24) are bent in horizontal plane in a straight, upwardly and/or downwardly manner.
9. Knife mill according to one of claims 1 to 8, characterised in that the knife rotor (74) includes several upwardly bent central knifes (27) and/or re-cutting knifes (43, 44) that rotate close to the filter ring (40).

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