EP2383037B1 - Device for grinding feedstock - Google Patents

Description

The invention relates to a device for comminuting feed material according to the preamble of patent claim 1.

Such devices are assigned to the field of mechanical engineering, in particular the conversion of a starting material into a final product of a predetermined shape and size by means of comminution. Such devices include disc mills, such as those from the DE 202 16 056 U1 are known. Such disc mills have a rotor which cooperates within a housing with a stator. The rotor consists essentially of a carrier disk, which is equipped over its outer peripheral portion with lying in the disk plane grinding tools. The grinding tools are in axial distance while maintaining a Mahlspalts stationary stator opposite, which are arranged on the housing inner wall concentrically around the axis of rotation around.

Both rotor and stator tools can be formed by segments and are screwed to the carrier disk or the housing wall. This very time-consuming work not only increases the assembly costs for wear-related tool change, but also increases the proportion of downtime of the disc mill, which precludes efficient use. For this reason, disk mills already use rotor and stator tools, which consist of a complete ring that can be exchanged as a whole. Although the tool change times are thereby shortened, the profile of the grinding tools is limited to a substantially radial corrugation in terms of production technology.

The state of the art also includes mills, such as those in the EP 2 070 596 A1 are described. The mill disclosed therein has a cone-shaped housing, the inner circumference of which is provided with a hollow truncated cone-shaped Mahlbahneinsatz to form a stator. Within the Mahlbahneinsatzes coaxial with a rotor is arranged, whose rotor tools are formed by pendulum-mounted, radially aligned impact plates that stroke while maintaining a Mahlspalts on the inner circumference of the stator along. The hollow truncated cone-shaped Mahlbahneinsatz forms the stator and is used as a whole in the housing, with a clamping ring on the larger diameter end face of the housing securing against axial changes in position of the grinding track insert guaranteed. As with the aforementioned one-piece tool rings in disc mills, so here only a substantially coaxial corrugation on the inner circumference of the grinding track insert is possible due to the monolithic design of the Mahlbahneinsatzes here. Variations in the geometry of the corrugation in order to adapt the surface of the stator tools effective for the comminution to a specific feed material or to achieve a specific processing result are not possible.

The US 3,873,047 discloses a breaker with a rotor with clubs and a cylindrical housing surrounding the rotor. On the inner circumference of the housing a plurality of axially extending, an impact path forming crushing bars is arranged. The crushing bars are held in position on one side by a circumferential dovetail flange and on the other side by clips.

From the JP 53070471 U a cylindrical comminution device with a rotor-stator system is known in which the stator tools are fixed between an upper and lower mounting ring.

When in the DE 197 23 705 C1 described mill segments of a grinding path are arranged on the inner circumference of a cylindrical housing, which are defined between the housing bottom and the housing cover.

The from the DE 202 11 899 U1 and EP 2 070 596 A1 known eddy current mills each have a conical housing with a grinding path running along the inner circumference. While the grinding path along its upper edge is supported on the housing cover, the lower edge is clamped by means of a detachable flange.

Against this background, the object of the invention is to further develop known devices with regard to the shortest possible downtimes during the tool change and the greatest possible flexibility in the adaptation of the stator tools to the feed material and the properties of the end product.

This object is achieved by a device having the features of patent claim 1.

Advantageous embodiments will be apparent from the dependent claims.

Thanks to the invention, it is possible at the same time to satisfy the mutually exclusive requirements in the prior art for the fastest possible change of the comminution tools on the one hand and the greatest possible freedom in selecting the type of corrugation of the comminution tools within a device.

By segment-like design of the stator, it is possible that two successive segments have a different corrugation, whereby both the intensity of the crushing and the residence time of the feed material in the crushing can be controlled. At the same time the segments are placed for mounting only in the stator and then fixed with a clamping element in position. In this way, extremely short tool change-related downtimes can be achieved. Thus, the invention enables a more economical operation of the device according to the invention by a simplified tool change with simultaneous qualitative improvement of the processing result due to the ability to better adapt the stator to the respective conditions.

The invention is explained in more detail below with reference to an embodiment shown in the drawings, wherein further features of the invention and additional advantages will become apparent. Where appropriate find the same or similar features of different embodiments identical reference numerals use.

Fig. 1

einen Vertikalschnitt durch eine erfindungsgemäße Vorrichtung entlang der in Fig. 2 dargestellten Linie I - I,

Fig.2

einen Horizontalschnitt durch die in Fig. 1 dargestellte Vorrichtung entlang der dortigen Linie II - II,

Fig.3

ein Detail der in Fig. 1 dargestellten Vorrichtung in den mit III gekennzeichneten Bereichen, die

Fig. 4 bis 6

alternative Ausführungsformen zu der in Fig. 3 gezeigten Lösung und die

Fig. 7 bis 13

Detaillösungen in Verbindung mit Vorrichtungen in Form von Scheibenmühlen.

It shows

Fig. 1

a vertical section through a device according to the invention along the in Fig. 2 illustrated line I - I,

Fig.2

a horizontal section through the in Fig. 1 shown device along the local line II - II,

Figure 3

a detail of in Fig. 1 illustrated device in the areas marked with III, the

4 to 6

alternative embodiments to those in Fig. 3 shown solution and the

Fig. 7 to 13

Detailed solutions in connection with devices in the form of disk mills.

The Fig. 1 and 2 give a vertical and horizontal section through a device according to the invention in the form of a mill 1 again. One sees a frame-like, made of steel profiles substructure 2, which forms with its top a horizontal platform 3 with a central opening 4. The substructure 1 carries the mill 1 according to the invention, whose axis of rotation 5 is oriented perpendicular to the platform 3 and extends through the central opening 4.

The mill 1 comprises a housing 6 with a lower part 7, which is formed by a cylindrical trough. The bottom 8 of the tub has a circular, concentric with the axis of rotation 5 opening 9. Upwards, the lower part 7 is open, wherein the edge is formed by a circumferential annular flange 10. The annular flange 10 serves as a support and Attachment of a concentric bearing ring 11, which is formed angularly in cross-section and the horizontal leg is connected to the annular flange 10.

Upwards, the housing 6 continues in a bell-shaped, hollow truncated cone-shaped upper part 12, the larger diameter underside of which is open and assigned to the lower part 7 and whose smaller diameter upper side has an opening 14 which is bounded by a circumferential, radially inwardly pointing collar 13. A removable lid 15 is detachably screwed to the collar 13 and has a concentric feed opening 16, to which a supply nozzle 17 connects. The arrow 18 embodies the feed material which is fed axially to the mill 1 through the feed pipe 17.

The larger diameter underside of the upper part 12 has a circumferential on the outer circumference annular flange 19, which is supported by adjusting screws 20 on the vertical leg of the bearing ring 11. In the housing portion between the annular flange 19 and the larger diameter end face of the upper part 12 of the outer housing shell is cylindrical in order to be accurately guided and axially displaceable within the bearing ring 11. About the adjusting screws 20, the distance between the lower part 7 and upper part 12 can be adjusted.

The housing upper part 12 forms with its inner circumference the stator, along which fifteen, the crushing path-forming segments 21 are arranged. The longitudinal sides 22 of the segments 21 are designed for this purpose so that they each extend in axial planes with respect to the axis of rotation 5. The circumferentially butted segments 21 form in this way the stator of the rotor-stator system. To secure the relative position of the segments 21 to each other, it is also possible to provide the mutually associated longitudinal sides 22 of two adjacent segments 21 with positive locking elements, for example in the form of tongue and groove, which is not shown in the drawing.

The cross section of the segments 21 is above all Fig. 2 out. Accordingly, the segments 21 have a plane rear side 23 and lie only with their longitudinal sides formed by the rear side 23 and longitudinal sides 22 in each case linearly on the conical inner jacket of the upper part 12, resulting in a polygonal-like course of the back of the crushing path. The linear bearing along the longitudinal edges also facilitates mounting against flat storage, since production-related inaccuracies within the storage area would hinder a rich resting of the segments 21. Since the inside of the upper housing part 12 has a constant curvature, formed between the upper housing part 12 and the rear sides 23 of the segments 21 cavities 58 with a circular segment-shaped cross section, which can serve for example for the passage of a cooling medium. The front side 24 of the segments 21 has a circular arc-shaped curvature and is equipped with a corrugation.

The size of the resulting between the segments 21 and the inside of the housing upper part 12 cavities 58 depends inter alia on the number of segments 21. The invention thus prefers a number of segments between 12 and 20, preferably between 15 and 18. A segment 21 thus extends over a 1/12 to 1/20, preferably over 1/15 to 1/18 of the inner circumference of the stator.

The special design of the two transverse sides 25 of the segments 21 will later under the Fig. 3 to 6 described in more detail.

Inside the housing 6, one sees a rotor 26 rotating about the rotation axis 5. The rotor 26 comprises a shaft 27, which is held coaxially with the rotation axis 5 within a cylindrical shaft bearing 28 in bearing groups 29. Here, the shaft bearing 28 is inserted over part of its length in the opening 9 in the bottom 8 of the lower part 7, wherein the shaft bearing 28 outer circumferential annular flange 30 for positionally accurate attachment of the rotor 26 relative to the housing 6 is used. On the outside of the housing 6 lying end of the shaft 27 is seated a multi-pulley 31 which is coupled to a drive not shown.

At the opposite end of the drive shaft 27, a baffle plate 32 is fixed concentrically to the rotation axis 5 frontally. The top of the feed opening 16 facing upper side arranged in the peripheral region Schlagklötze 33 form a first crushing stage for the reaching over the supply nozzle 17 into the mill 1 feed.

At an axial distance to the baffle plate 32 is also a concentric sitting on the shaft 27 first carrier disk 34, on the circumference of pairs rotor tools in the form of impact plates 35 are arranged. In this case, the effective edges of the impact plates 35 run while maintaining a radial working gap parallel to generatrices of the Stator. Plan parallel and at an axial distance is arranged concentrically on the drive shaft 27 in the direction of the lower part 7 a first baffle plate 36. The first baffle plate 36 serves to control the residence time and the material flow through the mill 1 according to the invention.

A further comminution stage is formed by a second carrier disk 37, which is fastened concentrically on the shaft 27 and, like the first carrier disk 34, is equipped with impact plates 35 on its circumference. In the direction of flow through the mill 1 finally follows a second, concentric on the shaft 27 seated baffle plate 38th

Out Fig. 3 the attachment of the segments 21 on the upper part 12 of the housing 6 is shown in detail. It shows Fig. 3 a cut, as in Fig. 2 is indicated with III - III and thus falls into the butt joint of two adjacent segments 21.

Each segment 21 has its attachment to the upper part 12 along the two transverse sides 25.1 and 25.2 each have a circular arc-shaped strip portion 39.1 and 39.2. In the installed state, the strip sections 39.1 and 39.2 of all segments 21 form a ring strip which runs concentrically around the axis of rotation 5.

For positive reception of the strip portions 39.1 on the first transverse side 25.1 is in the upper housing part 12 on the inside of the collar 13 a likewise concentric with the axis of rotation 5 circumferential annular groove 40 is arranged. This allows when turning the upper part 12 for insertion of the segments 21 with their strip portions 39.1 in the annular groove 40. The segments 21 arrive only with the longitudinal edges formed by the longitudinal sides 22 and the back 23 on the inside of the upper part 12.

For attachment of the segments 21 in the region of the larger diameter underside of the upper part 12 there is also a concentric extending clamping ring 41 is provided which can be clamped by means of screws 42 against the end face of the upper part 12. The clamping ring 41 extends with its inner circumference radially inwardly over the opening on the underside of the upper part 12 and has an annular projection 43 projecting axially out of the ring plane, which when placing the clamping ring 41 onto the upper part 12 already fitted with segments 21, the strip sections 39 engages behind the second transverse side 25.2 of the segments 21 and thus ensures their positionally accurate position.

Opposite the in Fig. 3 The embodiment shown in FIG Fig. 4 represented a simplified in terms of the preparation of the device solution. The positive connection in the region of the first transverse side 25.1 is not generated via a tongue and groove construction. Instead, the first transverse side 25.1 and the upper housing part 12 in the common contact surface are flat and lie in a radial plane with respect to the axis of rotation 5. In the region of the clamping ring 41, the two embodiments are the same 3 and 4 , so that what is said there applies.

In the embodiment according to Fig. 5 corresponds to the anchoring of the first transverse side 25.1 in the upper housing part 12 of the below Fig. 3 described. By contrast, the second transverse side 25.2 has a plane surface extending in a radial plane, on which a correspondingly designed clamping ring 41.1 acts.

The greatest degree of simplification is shown by the embodiment according to FIG Fig. 6 , There, both the first upper side 25.1 and the second upper side 25.2 of the segments 21 are flat and are held in the axial direction by corresponding planar bearing surfaces in the upper housing part 12 and on the clamping ring 41.1. The embodiment according to Fig. 6 is sort of a combination of in the 4 and 5 A position assurance of the segments 21 in the radial direction results from the annular arrangement of the segments 21 about the axis of rotation 5, wherein the segments 21 support each other over their longitudinal sides 22 and movements are prevented radially inwardly by the vault formation.

The Fig. 7 to 13 relate to different arrangements of the segments 21 on stationary or rotating support elements of disc mills, for example, according to the mentioned in the introduction to the description DE 202 16 056 U1 , wherein the fastening planes each lie in a radial plane with respect to the axis of rotation 5.

In Fig. 7 is denoted by the reference numeral 44, a support member, such as a rigid or rotating carrier disk or a rigid housing wall. On the side of the support element 44 facing the refining gap, the comminution tools in the form of segments 21 arranged in a circle about the axis of rotation 5 can be seen. In order to fasten the segments 21, a recess 45 which is rectangular in cross-section and runs concentrically around the axis of rotation 5 is arranged in the surface of the support element 44. The recess 45 is formed by a bottom 46, an outer wall 47 and an inner wall 48.

The recess 45 serves to receive the segments 21 which abut with their rear side 23 over the entire surface of the bottom 46 and with its first transverse side 25.1 over the entire surface of the outer wall 47. The radial size of the recess 45 is chosen so that there is an annular space between the inner wall 48 and the segments 21, which serves to receive a clamping ring 41.3. In this case, the clamping ring is supported 41.3 with its inner circumference on the inner wall 48, while the outer periphery decreases to form an oblique peripheral surface in the direction of the bottom 46 side facing. About this inclined surface of the clamping ring 41 cooperates with the segments 21, the second transverse side 25.2 extends linearly to form a correspondingly inclined surface to the rear side 23. In this way, with the tightening of the screws 42 via the clamping ring 41.3 a radially outwardly against the outer wall 47 and axially against the bottom 46 acting on the clamping force transmitted to the segments 21.

Fig. 8 differs therefrom only in that the outer wall 47 is undercut towards the bottom 46. The complementarily shaped first transverse side 25 of the segment 21 engages behind the undercut wall 47 and is additionally secured in this way against axial lifting.

In the Fig. 9 The arrangement shown differs from the two previously described in that the support member 44 has no channel-like recess 45, but a substantially planar surface, which has only on the outer peripheral edge protruding from the plane of an annular wall 50, the radially inwardly facing side 49 undercut is such that these areas correspond to the corresponding outer peripheral area of the Fig. 8 correspond to the arrangement shown.

The clamping ring 41.4 has an outer circumference corresponding to the in Fig. 8 So described acts with the inclined second transverse side 25.2 as in the Fig. 8 described together. By contrast, the inner circumference of the clamping ring 41.4 in the direction of the support member 44 toward greatly expanded to form a slope 57 to a To obtain the largest possible support surface 56 of the clamping ring 41 on the flat top of the support member 44.

The arrangement according to Fig. 10 corresponds in many parts of the under Fig. 7 described. Differences exist in the region of the second transverse side 25.2 of the segments 21, which widens stepwise to the rear side 23 of the segments 21 to form a rectangular strip section 39.1. The clamping ring 41 has a complementarily shaped outer periphery with an annular flange 51, which biases the strip portion 39.1 axially against the bottom 46.

The arrangement accordingly Fig. 11 resembles the under Fig. 10 described with the difference that the segments 21 in the region of the first transverse side 25.1 to the rear side 23 towards stepwise wide and thereby form a strip portion 39.2, which engages positively in a corresponding groove 52 in the outer wall 47. The segments 21 thus have an axisymmetric cross section.

This differs from the in Fig. 12 shown arrangement by a cross-sectionally axisymmetric clamping ring 41.6. The clamping ring 41.6 has as in Fig. 11 described a circumferential on the outer circumference annular flange 51. In addition, there is a second annular flange 53, which is arranged in an analogous manner on the inner circumference of the clamping ring 41.6. The inner wall 48 has an annular recess 55 to a complementary geometry, so that when tightening the screws 42 of the clamping ring 41.6 is supported both on the strip portion 39.1 of the second transverse side 25.2 and recess 55 in the inner wall 48 and thus symmetrical is charged.

A variant of this is the subject of in Fig. 13 disclosed arrangement. Here, the transverse sides 25.1 and 25.2 which extend in the direction of the rear side 23 each have strip sections 39.3 and 39.4, with bevels 54 inclined towards the outer circumference or inner circumference in the direction of the rear side 23. During clamping of the clamping ring 41.7, which is complementary in the contact region to the segment 21, it additionally becomes to the directed against the bottom 46 clamping force generates a radially outward component. For a symmetrical loading of the clamping ring 41.7 provide an axisymmetric configuration of the clamping ring 41.7 in cross section and a complementary shape of the wall 48th

It is understood that the invention is not limited to the individual feature combinations of the respective embodiments according to the Fig. 1 to 6 is limited. Rather, such feature combinations are within the scope of the invention, which consist of individual features of different embodiments according to the Fig. 1 to 6 put together.

Claims (9)

1. Device for the comminution of feedstock with a rotor (26) rotating around an axis (5) within a housing (6) with rotor tools (35) arranged on a circumferential circle in the outer circumferential zone and a stator matching the rotor (26) with stator tools arranged concentrically on the outer circumferential zone and forming a comminution track wherein the rotor tools (35) and the stator tools are facing each other with a spacing in between thus forming a comminution gap and the stator tools being formed by segments (21) which abut with their rear side (23) on the stator and lean against each other with their longitudinal side (22) to form the comminution track, wherein the segments (21) are fastened on the stator by positive-locking fit with their first transversal side (25.1) and their second transversal side (25.2), wherein the stator shows a clamping element (41) interacting with the first transversal side (25.1) and/or the second transversal side (25.2) to clamp the segments (21) against the stator and wherein the rotor (26) and the stator have a cylindrical or conical shape, characterized in that the segments (21) show a plane rear side (23) and abut on the stator along the longitudinal edges formed by the rear sides (23) and the longitudinal side (22) thus forming cavities (58).
2. Device according to claim 1, characterized in that the first transversal side (25.1) and/or the second transversal side(s) (25.2) of a segment (21) widen(s) from the front side (24) of the segment (21) towards its rear side (23).
3. Device according to claim 2, characterized in that the first transversal side (25.1) and/or the second transversal side(s) (25.2) widen(s) gradually while forming a ledge section (39).
4. Device according to claim 2, characterized in that the first transversal side (25.1) and/or the second transversal side(s) (25.2) widen(s) linearly while forming a slanted surface (47).
5. Device according to one of the claims 1 to 4, characterized in that the shape of one of both transversal sides (25.1, 25.2) of a segment (21) remains the same from the segment's (21) front side towards its rear side (23), and the other transversal side (25.1, 25.2) widens.
6. Device according to one of the claims 1 to 5, characterized in that the first transversal side (25.1) and/or the second transversal side (25.2) and the respectively matching clamping element show(s) contact surfaces having complementary shapes.
7. Device according to one of the claims 1 to 6, characterized in that the clamping element shows a symmetric section.
8. Device according to one of the claims 1 to 7, characterized in that the clamping element consists of a clamping ring (41, 41.1, 41.2, 41.3, 41.4, 41.5, 41.6, 41.7).
9. Device according to claim 1, characterized in that the shapes of the first transversal side (25.1) and of the second transversal side (25.2) of a segment (21) remain the same.

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