Comminuting device

Abstract

The invention relates to a comminuting device including a cylinder casing which surrounds a comminuting chamber, in which several rotors can be operated independently from each other with individual drives, said rotors being driven by concentric shafts which are arranged concentrically to the central axis (z) of the comminuting chamber, said concentric shafts having a central shaft and at least one outer hollow shaft surrounding said central shaft. At least one lubricant line for connecting to a lubricant supply is arranged in the central shaft and/or in a shaft casing, the lubricant line being connected by at least one radial lubricant through guide to at least one bearing of the rotors.

Claims

1. A comminution device comprising a cylinder surrounding a comminution chamber, in which a plurality of rotors are driven independently from each other by their own drives, the plurality of rotors are driven via a plurality of concentrical shafts which are arranged concentrically to a central axis (z) of the comminution chamber, the plurality of concentrical shafts comprises a central shaft as well an outer hollow shaft surrounding the central shaft, whereby in the central shaft at least one lubricant pipe connected with a lubricant supply is arranged, the lubricant pipe is connected with a plurality of bearings of the plurality of rotors via a radial lubricant duct, wherein the plurality of concentrical shafts comprises in the area of the plurality of concentrical shafts' lubricant ducts, one radial extending lubricant channel which abuts to a wall of the plurality of concentrical shafts in an area of the the plurality of concentrical shafts lubricant ducts located therein.

2. The comminution device according to claim 1, wherein the plurality of concentrical shafts' lubricant duct leads to an annular section in which a shaft bearing is located.

3. The comminution device according to claim 2, wherein the annular section is defined in a first axial direction by a bearing and in an opposite second axial direction by a lubricant seal.

4. The comminution device according to claim 3, wherein the lubricant seal is permeable to gas.

5. The comminution device according to claim 1, in which the radial extending lubricant channel comprises at least in an area abutting to the wall a contact material which has a low friction with respect to a material of the shaft.

6. The comminution device according to claim 1, wherein at an end face of the plurality of rotors the lubricant pipe is connected with an annular feed chamber.

7. The comminution device according to claim 1, wherein in the central shaft there is an inner space and/or between the plurality of concentrical shafts there is a plurality of intermediate spaces, the plurality of intermediate spaces are provided as at least partially gas feed spaces in connection with a gas supply, the gas feed spaces are connected with at least one shaft bearing arranged between the plurality of concentrical shafts.

8. The comminution device according to claim 7, wherein the gas feed space is connected to a rotary mounted end piece comprising a gas feed opening to be connected with the gas supply.

9. The comminution device according to claim 7, wherein at least one of the plurality of concentrical shafts comprise a radially extending gas duct being connected to a shaft bearing.

10. The comminution device according to claim 9, wherein the gas leads to a first annular gas section which is defined in a first axial direction by a bearing and in an opposite second axial direction by an annular gas seal.

11. The comminution device according to claim 7, wherein all of the plurality of intermediate spaces between the plurality of concentrical shafts are connected to a gas supply.

12. The comminution device according to claim 1, wherein the central shaft comprises an axial hollow space which is on one hand connected with an intermediate space via a gas duct extending radially in the central shaft and is connected with a gas supply.

13. The comminution device according to claim 12, wherein the gas supply is realized by a fan.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows a partially cutaway view of a comminuting device with three rotors and three shafts which are concentric to one another with a combined gas and lubricant feed.

DETAILED DESCRIPTION OF THE INVENTION

(2) FIG. 1 shows a comminuting device 10 in a schematic partially cutaway view along its longitudinal axis z. The cylinder material and the entire bottom region of the comminuting device are not shown. The comminuting device 10 includes a motor/bearing block 12 which rotationally supports three shafts which are concentric to one another, and which drives specifically a central hollow shaft 14, a first outer hollow shaft 16 which surrounds the latter, and a second outer hollow shaft 18 which surrounds the first outer hollow shaft 16. The three hollow shafts 14, 16, 18 are located concentrically around the central axis Z of the comminuting chamber. At least one, preferably two, and most preferably each concentric shaft 14, 16, 18 bears striking tools 20 in order to crush material supplied from above (for example mineral conglomerates). The three shafts 14, 16, 18 can be controlled individually via three separate motors in the motor/bearing block 12 so that they can each be driven in opposite directions and with increasing speed. In this way very effective comminution of the supplied material can be achieved. The drawing does not show a cylinder jacket which surrounds the rotors 14, 16, 18 and a comminuting chamber defined in its interior. The central hollow shaft 14 on its lower end is supported on the motor/bearing block 12 and on the opposite upper end by means of a first bearing 22 on a fixed structure 24 of the comminuting device 10, for example a wall. The first outer hollow shaft 16 is radially supported and centered relative to the central hollow shaft 14 with a second bearing 26. The second outer hollow shaft 18 is radially supported and centered relative to the first outer hollow shaft 16 with a third bearing 28. The three bearings 22, 26, 28 provide for the concentric shafts to remain concentrically aligned when material is being comminuted. The sections of the concentric shafts 14, 16, 18 which are not covered to the outside form rotors 30, 32, 34 on which the striking tools 20 are anchored in a manner which is not detailed. Preferably the striking tools 20 are held interchangeably on the rotors 30, 32, 34. The striking tools 20 can be bars or chains or similar known functional elements, as are known from German Patent No. DE 10 2013 110 352 A. When materials are being comminuted, in particular mineral-containing materials, a large amount of dust is formed which could rapidly adversely affect or destroy the bearings of the shafts.

(3) So that the bearings are well lubricated, lubricant is fed to the bearings 22, 26, 28. In the comminuting device 10 shown the central cavity 62 of the central hollow shaft 14 is made as a lubricant line which is connected via a lubricant feed line 64 to a lubricant feed 66, for example a pressurized lubrication apparatus. In the region of the first bearing 22 the central cavity 62 has a first radial lubricant duct 68 which leads directly to the first bearing 22 and thus leads to lubrication of the first bearing 22. A second lubricant duct 68 leads into an inner annulus 70 which is made between the second bearing 26 and an annular lubricant seal 72. The lubricant seal 72 causes the lubricant to be fed only to the inner annulus 70 and thus to the bearing 26 and not into the underlying first intermediate space 44. In the central hollow shaft 14 there is moreover another lubricant duct 68 which discharges into a lubricant channel 74 which is attached radially outside on the central hollow shaft 14. The lubricant channel 74 adjoins the inside wall 76 of the first outer hollow shaft 16 on the outside and is located at a height at which the lubricant channel 74 can be aligned with an outer lubricant duct 78 in the first outer hollow shaft 16. In this way the lubricant channel 74 will align in a certain rotational position of the central hollow shaft 14 relative to the first outer hollow shaft 16 with the outer lubricant channel 78 of the first outer hollow shaft 16. Thus lubricant is supplied to an outer annulus 80 between the first outer hollow shaft 16 and the second outer hollow shaft 18, which outer annulus 80 is bordered to the bottom by a ring-shaped lubricant seal 72 and to the top by the third bearing 28. In this way enough lubricant is also fed to the third bearing 28 which lies farthest to the outside. If the short alignment of the lubricant channel 74 with the outer lubricant duct 78 is too short to feed enough lubricant to the outer annulus 80 and thus to the third bearing 28, it can be provided that an electronic control determines the position of the shafts 14, 16, 18 to one another via corresponding sensors and can position the central outer hollow shaft 14 and the first outer hollow shaft 16 in one lubricant position relative to one another such that the lubricant channel 74 is aligned with the outer lubricant duct 78. In this position the third bearing 28 can be lubricated. If it is not aligned with the outer lubricant duct 78, the lubricant channel 74 is closed by the inside wall 76 of the first outer hollow shaft 16. The lubricant channel 74 in this sense can slide either gently along the inside wall 76 of the first outer hollow shaft 16 or it has a minimum distance to the latter which prevents the escape of lubricant.

(4) Moreover the central cavity 62 is connected to a third lubricant duct 68 which feeds lubricant to the uppermost bearing 22. Thus lubricant is supplied to all bearings 22, 26, 28 via the central cavity 62 and the lubricant ducts 68.

(5) In addition or alternatively to the central cavity 62, a lubricant line 63 (shown by the broken line) can be located in one shaft wall 14 in the form of an axial bore which is connected to the lubricant ducts 68, preferably all of them. In this way then the central cavity 62 can be used for gas feed. This alternative can also be used when the central shaft 14 does not have a central cavity 62.

(6) The first intermediate space 44 is connected via a gas line 38 to a gas feed 40, for example a fan. The lubricant seal 72 between the central hollow shaft 14 and the first outer hollow shaft 16, as well as between the first outer hollow shaft 16 and the second outer hollow shaft 18, are permeable to gas. Moreover, in the first outer hollow shaft 16 there is a gas duct 42 through which the gas, for example air, which has been supplied from a gas feed 40 is also fed to the second intermediate space 52 between the first outer hollow shaft 16 and the second outer hollow shaft 18. In this way the second bearing 26 as well as the third bearing 28 are supplied with gas. In this embodiment the two bearings 26, 28 are not only supplied with lubricant, but also with a gas, for example ambient air, so that they are not fouled with dust of the comminuted matter and thus have a long service life.

(7) On the free end of the central hollow shaft 14 there is a central cover 46 which closes the central cavity 36 towards the free end. On the end of the first outer hollow shaft 16 there is a first ring cover 48 which is spaced apart from the central hollow shaft 14 by a first gap 50. This first ring cover 46 on the one hand affects a mechanical barrier against the penetration of dust from the comminuting chamber. On the other hand, due to the narrowing of the exit in the first gap 50 between the central hollow shaft 14 and the first ring cover 48 the available flow space is extremely reduced; this leads to the gas emerging there with a correspondingly increased velocity. The safeguarding of the second bearing 26 against the penetration of dust is greatly improved. In the first outer hollow shaft 16 there is a radial gas duct 42 so that the gas is routed into a second intermediate space 52 which is located between the first outer hollow shaft 16 and the second outer hollow shaft 18. From there the gas is fed to the third bearing 28 and travels through a second gap 54 between the first outer hollow shaft 16 and a second ring cover 49 into the comminuting chamber. In the second gap 54 the gas velocity is in turn increased so that this offers very good protection against the penetration of dust and larger material grains into the third bearing 28.

(8) The first bearing can be located outside of the comminuting chamber, in which case gas flushing is not unconditionally necessary.

(9) This invention is not limited to the described exemplary embodiments, but can be varied in any way within the protective domain of the attached claims.

REFERENCE NUMBER LIST

(10) 10 comminuting device (first embodiment) 12 motor/bearing block 14 central hollow shaft 16 first outer hollow shaft 18 second outer hollow shaft 20 striking tools 22 first bearing 24 fixed structure 26 second bearing 28 third bearing 30 first rotor 32 second rotor 34 third rotor 36 central cavity 38 gas line 40 gas feed 42 gas duct 44 first intermediate space 46 central cover 48 first ring cover 49 second ring cover 50 first gap 52 second intermediate space 54 second gap 60 comminuting device (second embodiment) 62 central cavity 64 lubricant feed line 66 lubricant feed 68 lubricant duct 70 inner annulus 72 lubricant seal 74 lubricant channel 76 inside wall of the first outer hollow shaft 78 outer lubricant duct 80 outer annulus