A COMMINUTING MACHINE COMPRISING A ROTOR SYSTEM AND A METHOD FOR COMMINUTING FEEDSTOCK

Abstract

The invention relates to a comminuting machine (8) with a rotor system, in particular a knife ring flaker, in which the feedstock is conveyed pneumatically in the axial direction into the central region of the rotor (10) and is conveyed in the radial direction to the comminuting tools arranged around the rotor (10) in the manner of a ring. In order to uniformly wear the knives extending in the axial direction in such devices, it is proposed to provide in the central region (14) an insert (15) which is rotatably driven by a motor (22) and which has separate chambers (16, 17) with which the feedstock entering said chambers is dispensed at axially and radially to different regions. This insert (15) can, in particular, be designed as a rotor, which has a plurality of chambers which are especially shaped in the cross-section in the manner of a circular sector.

Claims

1. A comminuting machine comprising a rotor system in which feedstock is conveyed pneumatically in an axial direction into a central region of a rotor and is fed to comminuting tools which are arranged in a radial direction around the rotor in a form of a ring, wherein an insert is arranged in a central region, which is rotatably driven by a motor and which assigns an input surface of the central region to separate chambers, which each discharge the feedstock entering them to axially different regions.

2. The comminuting machine according to claim 1, wherein the insert covers an entire essentially vertically situated input surface of the central region.

3. The comminuting machine according to claim 1, wherein the separate chambers have side walls extending in the radial direction.

4. The comminuting machine according to claim 1, wherein the chambers have access openings having the form of circular sectors.

5. The comminuting machine according to claim 1, wherein the insert has chambers with outlet openings which are arranged on a jacket surface which delimits the insert in a circumferential direction.

6. The comminuting machine according to claim 1, wherein the insert has chambers with outlet openings which are arranged on a bottom which delimits the insert in the axial direction.

7. The comminuting machine according to claim 1, wherein the chambers have side walls which are provided with a wear-protection element.

8. The comminuting machine claim 1, further comprising an external air opening arranged upstream of the insert in a flow direction of the pneumatically conveyed feedstock.

9. The comminuting machine according to claim 1, wherein the insert is arranged outside an axis of the rotor and/or obliquely with respect to the input surface of the central region.

10. The comminuting machine according to claim 1, wherein the chambers have different geometries and/or different axial depths.

11. The comminuting machine according to claim 3, wherein the side walls are arranged at an angle to a perpendicular on the radial direction of the insert.

12. The comminuting machine according to claim 3, wherein the side walls are bent in the radial direction and/or perpendicularly thereto.

13. The comminuting machine according to claim 1, wherein the insert is integrated in a door of the comminuting machine.

14. The comminuting machine according to claim 1, further comprising drivers arranged in the chambers.

15. The comminuting machine according to claim 14, wherein the drivers are provided with a wear-protection element.

16. The comminuting machine according to claim 1, further comprising guide elements arranged in or on the insert, on a jacket surface and/or a bottom surface.

17. The comminuting machine according to claim 16, wherein a guide element is arranged outside the chambers.

18. The comminuting machine according to claim 1, wherein a rotational speed of the insert is configured to be controlled or regulated via a control device depending on a material flow.

19. The comminuting machine according to claim 1, wherein a rotational speed of the insert is independent of a rotational speed of a knife ring and/or the rotational speed of the rotor, and is lower than the rotational speed of the knife ring and/or the rotational speed of the rotor.

20. The comminuting machine according to claim 7, wherein the wear protection has a geometry which deviates from the side walls.

21. A method for comminuting feedstock in a comminuting machine, the method comprising: pneumatically conveying feedstock in an axial direction into a central region of a rotor; supplying the feedstock to comminuting tools arranged in a radial direction around the rotor in the manner of a ring, and assigning, in a central region of the comminuting machine, incoming feedstock to separate chambers via an insert, wherein the insert is rotatably driven by a separate motor and delivers the feedstock into axially and radially different regions.

22. The method according to claim 21, wherein the feedstock in the insert is deflected from its original movement and undergoes an acceleration.

23. The method according to claim 22, wherein the feedstock in the insert is at least partially accelerated counter to gravity.

24. The method according to claim 21, wherein a rotational speed of the insert is regulated or controlled depending on a material flow.

25. The method according to claim 21, wherein the insert rotates at a rotational speed which is independent of a rotational speed of a knife ring and/or a rotational speed of the rotor, and is lower than the rotational speed of the knife ring and/or the rotational speed of the rotor.

Description

[0047] The drawings show as follows:

[0048] FIG. 1 shows a sectional view of a comminuting machine with an upstream heavy material separator,

[0049] FIG. 2 shows an insert with separate chambers in the sectional view,

[0050] FIG. 3 shows a further embodiment of an insert in the sectional view;

[0051] FIG. 4 shows an insert in top view, and

[0052] FIG. 5 shows a further embodiment of an insert in the top view.

[0053] FIG. 1 shows a comminuting machine 8 according to the invention with an upstream heavy material separator 4. Material or feedstock to be comminuted, in particular coarser wood parts, is fed onto a vibrating channel 1 and conveyed by the latter by means of an unbalanced motor 2. The material is guided in this case via a magnetic roller 3, with which ferromagnetic contaminants are separated from the material falling from the vibrating channel 1.

[0054] The material flow 29 falls into a heavy material separator 4, where it is guided in a cascade-like fashion via pivotable guide plates 5.

[0055] By means of a blower 6, an air stream 30 is blown from below at the side into the heavy material separator 4 at a speed of about 15 to 20 m/s and is diverted via a guide plate 7 in such a way that feedstock falling from the guide plates 5 onto the guide plate 7 is blown upwards along the guide plate 7. The speed of the air stream 30 is adjusted in this case in such a way that, depending on the specific weight, impurities such as stones or the like cannot be moved upwards by the air stream 30 along the guide plate 7, but instead drop downwards out of the heavy material separator 4.

[0056] The feedstock detected by the laterally inflowing air stream 30 is blown or transported into the actual comminuting machine 8.

[0057] This comminuting machine 8 has externally a knife ring 9 which has a plurality of radially inwardly extending blades, the cutting edges of which extend in the axial direction. The knife ring 9 can either be fixed or be rotated about its central axis by a corresponding drive.

[0058] A rotor 10, which is set in rotation via a shaft 11, is arranged coaxially with this knife ring 9. Optionally, the rotational direction of this rotor 10 is preferably counter to the direction of rotation of the knife ring 9.

[0059] Radially on the outside, this rotor 10 has rotor blades 12 which extend parallel to the knives of the knife ring 9 and pass close to these knives so that the feedstock moved past the blades of the rotor blades is shaved. The shavings are removed from the comminuting machine 8 by a discharge chute 13 arranged below the knife ring 9.

[0060] In the example shown here, an insert 15 in the form of a distributor rotor sits in the central region 14 of the rotor 10. This distributor rotor is shown separately in FIGS. 2 to 5. It essentially has the shape of a truncated cone but can also be designed in a different way.

[0061] It can be seen that the insert 15 has several separate chambers 16, 17. Feedstock enters said chambers in a respective axial-parallel manner from the direction 18 through the access openings arranged on the top surface of the insert 15.

[0062] While the feedstock, in the chamber 16 shown in FIGS. 2 and 3 above, is discharged in the radial direction via a side opening 19 located on the conically extending peripheral surface of the insert 15 from the chamber 16 out of the insert 15, the feedstock entering the chamber 17 is discharged through a bottom opening 20 with an axial component, said bottom opening being located on the end face of the insert 15 forming the base area of the insert 15.

[0063] In this way, as shown in FIG. 1, the portion of the material flow 29 guided through the chamber 16 is guided in an axially front area A onto the rotor and thus onto the knife ring 9, while the portion of the material flow guided through the chamber 17 is guided to an axially rear region B onto the rotor 10 and thus onto the knives of the knife ring 9.

[0064] Through the arrangement of the side opening 19 or the bottom opening 20, it is in particular also ensured that the feedstock emerging from the insert 15 or the emerging material flow 29 precisely hits the rotor 10 in the regions provided which are assigned to them.

[0065] In addition, as shown in FIG. 3, guide elements 31, 32 can be arranged in or on the insert 15 in order to be able to selectively guide the incoming and outgoing material. The guide elements 32 arranged in the insert 15 give the material an additional impulse in the direction of the side opening 19 or the bottom opening 20. The shape of the guide elements 32 can be straight or curved. Furthermore, these can also be arranged in sections. The guide elements 31 arranged on and thus outside the insert 15 serve, on the one hand, to guide the material to the comminuting tools, here the knives of the knife ring 9, into the region A, B. On the other hand, these guide elements 31 can influence the swirling onto the feedstock after exiting from the side opening 19 and the bottom opening 20. Furthermore, the guide elements 31 can additionally be used for wear protection, such as, for example, the guide element 31 arranged behind a bottom opening 20, as shown in FIG. 3. This guide element 31 prevents the material emerging from the insert 15 from being guided to the rear wall of the comminuting machine 8, but rather is directed in the region B towards the comminuting tools. The arranged guide elements 31, 32 can all be realized individually or in any combination with one another.

[0066] In the exemplary embodiment illustrated here, it is provided that the distributor rotor has a total of four chambers, each forming a quadrant of the frustoconical insert 15. In the example illustrated here, chambers 16, 17, which have side openings 19 on the circumferential surface of insert 15, and such which have bottom openings 20 on the front or bottom surface of insert 15, thus alternate in the circumferential direction.

[0067] In principle, it is also possible to divide the insert 15, for example, into six or more chambers 16, 17 which essentially cover circular sectors. These chambers 16, 17 each have assigned side openings corresponding to different axial depths in the jacket surface of the distributor rotor. This is accompanied by an even greater equalization of the feedstock distribution in the axial direction of the comminuting machine 8.

[0068] As a result, the knives of the knife ring 9 are uniformly loaded over their length and therefore wear off evenly.

[0069] An essential aspect is that the insert 15 rotates, as shown in FIGS. 4 and 5 by the direction of rotation 21. This rotation is preferably in the same direction as the direction of rotation of the rotor 10. The insert 15 is thereby driven by a motor 22 via a shaft 23. This leads to the fact on the one hand that the material flow 29 guided through the insert 15 is directed outwards in the radial direction and, on the other hand, the material flow 29 is distributed in the circumferential direction via the rotor 10 or via the knife ring 9 by the rotary movement of the insert 15 in the direction of rotation 21. As a result, the wear of the blades of the knife ring 9 is thus further provided in a more uniform manner.

[0070] Since, as a result of the rotation of the insert 15, the individual particles of the feedstock impact the side walls 24 of the chambers 16 and 17, they are provided with flat wear-protection elements 25 which are screwed on in the present case. Should these wear-protection elements 25 be worn, they can be replaced so that the service life of the device is correspondingly prolonged.

[0071] Furthermore, it can be advantageous that one or more drivers 33 are arranged within the insert 15 or a chamber 16, 17. The drivers 33 additionally exert an impulse on the feedstock and thereby improve the distribution of the material flow in the comminuting machine 8. The drivers 33 preferably have a length expansion which does not extend as far as the circumferential surface of the insert 15. Furthermore, the size of the access opening into the chamber 16, 17 is not reduced by the drivers 33, as would be the case with the use of an insert with a larger number of chambers 16, 17. These drivers 33 can additionally comprise a wear-protection element 25.

[0072] It has been found that it is advantageous to optionally enrich the material flow 29, when entering the insert 15, with external air 26 from external air openings 27 arranged in front of the insert 15. In this way, it is to be prevented that unwanted sub-pressures or fluid-technical dead spaces form within the rotating insert 15, in which feedstock can accumulate. Thus, the distribution of the feedstock along the axial length of the rotor 10 is improved by this external air 26.

[0073] It should also be mentioned that the insert 15 proposed here, with its motor 22, etc., can also be mounted on a door 28 which carries it. Thus, comminuting machines 8, which optionally may be comparable in their basic concept, can be retrofitted with a corresponding rotatable insert 15.

TABLE-US-00001 List of reference numerals P0183WO 1 Vibrating channel 2 Unbalanced motor 3 Magnetic roller 4 Heavy material separator 5 Guide plate 6 Blower 7 Guide plate 8 Comminuting machine 9 Knife ring 10 Rotor 11 Shaft 12 Rotor blade 13 Discharge chute 14 Central region 15 Insert 16 Chamber 17 Chamber 18 Direction 19 Side opening 20 Bottom opening 21 Direction of rotation 22 Motor 23 Shaft 24 Side walls 25 Wear-protection elements 26 External air 27 External air opening 28 Door 29 Material flow 30 Air stream 31 Guide element 32 Guide element 33 Driver A Region B Region