Distribution metering device for a roller mill, roller mill with such a distribution metering device, method for grinding grinding stock, and roller mill comprising a switching cabinet with a cooling system

Abstract

A distribution metering device (1) for a roller mill which includes a housing (2) with at least one grinding stock inlet (3), at least one grinding stock outlet (4), and a feed roll (5) which is arranged in the housing (2) for metering grinding stock into a grinding gap of the roller mill through the grinding stock outlet (4). The feed roll is rotatable about a feed roll axis (SA). A conveyor shaft (6) is arranged in the housing (2) for distributing grinding stock along the feed roll (5). The conveyor shaft is rotatable about a conveyor shaft axis (FA). The conveyor shaft axis (FA) is substantially parallel to the feed roll axis (SA), and a first fill state sensor (7) is arranged in the housing (2) for ascertaining a first grinding stock fill state of the housing (2).

Claims

1. A milling installation, being a facility with a plurality of roller mills (14), wherein each roller mill (14) of the Plurality of roller mills comprises; at least two rollers arranged in a housing (2), a milling-material inlet (3), a milling-material outlet (4), a distributing and metering device (1) comprising a feeding roller, which is arranged in the housing, for metering milling material into a milling gap of the roller mill through the milling-material outlet, and a conveying shaft, which is arranged in the housing, for distributing milling material along the feeding roller, and wherein the roller mill (14) comprises a control unit (12) for controlling and/or regulating said roller mill (14), the control unit (12) being arranged in a switching cabinet (13) with a cooling system, which switching cabinet is arranged directly on the distributing and metering device (1) at the roller mill (14), and all connecting lines of the roller mill (14) are connected via the control unit (12) in the switching cabinet (13) at the roller mill (14).

2. The milling installation according to claim 1, wherein the cooling system comprises at least one Peltier element (17).

3. The milling installation according to claim 2, wherein the switching cabinet (13) additionally contains at least one power electronics component.

4. The milling installation according to claim 3, wherein the at least one power electronics component is selected from the group consisting of safety switches, main switches, soft starters, frequency converters (inverters) and heavy-current power lines.

5. The milling installation according to claim 1, wherein three lines are connected to the control unit (12).

6. The milling installation according to claim 1, wherein the switching cabinet isolates an interior of the switching cabinet (13) from an exterior of the switching cabinet.

7. The milling installation according to claim 6, wherein the switching cabinet (13) additionally contains at least one power electronics component.

8. The milling installation according to claim 7, wherein the at least one power electronics component is selected from the group consisting of safety switches, main switches, soft starters, frequency converters (inverters) and heavy-current power lines.

9. The milling installation according to claim 5, wherein the switching cabinet (13) additionally contains at least one power electronics component.

10. The milling installation according to claim 9, wherein the at least one power electronics component is selected from the group consisting of safety switches, main switches, soft starters, frequency converters (inverters) and heavy-current power lines.

11. The milling installation according to claim 1, wherein the switching cabinet isolates an interior of the switching cabinet (13) from an exterior of the switching cabinet.

12. The milling installation according to claim 11, wherein the switching cabinet (13) additionally contains at least one power electronics component.

13. The milling installation according to claim 12, wherein the at least one power electronics component is selected from the group consisting of safety switches, main switches, soft starters, frequency converters (inverters) and heavy-current power lines.

14. The milling installation according to claim 1, wherein the switching cabinet (13) additionally contains at least one power electronics component.

15. The milling installation according to claim 14, wherein the at least one power electronics component is selected from the group consisting of safety switches, main switches, soft starters, frequency converters (inverters) and heavy-current power lines.

Description

(1) The invention will be better described below on the basis of a preferred exemplary embodiment in conjunction with the figures, in which:

(2) FIG. 1 shows a schematic sectional view of the distributing and metering device according to the invention in a plane parallel to the feeding roller shaft;

(3) FIG. 2 shows a schematic sectional view of the distributing and metering device according to the invention in a plane perpendicular to the feeding roller shaft;

(4) FIG. 3 shows a schematic perspective view of the roller mill according to the invention with a distributing and metering device and a switching cabinet; and

(5) FIG. 4 shows a diagrammatic view of a milling installation having a plurality of roller mills.

(6) FIGS. 1 and 2 schematically illustrate a distributing and metering device 1. The distributing and metering device 1 comprises a housing 2 having a milling-material inlet 3 and a milling-material outlet 4. In the housing 2 there are arranged a feeding roller 5, which can be rotated about a feeding roller axis SA, and, above the feeding roller 5 in the milling-material flow direction, a conveying shaft 6. The conveying shaft in this case takes the form of a screw conveyor and can be rotated about the conveying shaft axis FA, which is parallel to the feeding roller axis SA. To drive the feeding roller 5 and the conveying shaft 6, respective motors 15 and 16 are present. The motors 15 and 16 are operatively connected to a control unit 12 (schematically illustrated by the dashed line).

(7) In the housing 2 there are arranged two filling level sensors 7 and 8 which are designed to determine the milling-material filling level in the housing and are likewise operatively connected to the control unit 12.

(8) The first filling level sensor 7 is arranged in the region of the milling-material inlet 3 at a first end of the feeding roller 5 and of the conveying shaft 6. The second filling level sensor 8 is arranged at the other end of the feeding roller 5 and of the conveying shaft 6. Two filling level sensors 7 and 8 are thus arranged at the two ends of the feeding roller 5 and of the conveying shaft 6. The milling-material inlet 3 is likewise situated not centrally as in the case of known devices, but is arranged above the first end of the feeding roller 5 and of the conveying shaft 6.

(9) In FIG. 2 there can also be seen the construction of a throttle device 10 which is used for setting a gap 9 which serves as a milling-material outlet 4 of the housing 2. The throttle device 10 comprises, in addition to actuators and bearings, an elongate profile 11 with a circular segment-shaped cross section. Rotating the profile 11 (schematically illustrated by the dashed position) allows the gap width of the gap 9 to be set.

(10) Also visible in FIG. 2 is the arrangement of the guiding arrangement 18 which takes the form of a chute. The guiding arrangement ends with an edge 19 close to the surface of the feeding roller 5. The edge 19 is arranged such that no milling material can pass under the feeding roller 5 or no milling material can remain in the feeding space; for example, the edge 19 can for this purpose be arranged at an angular distance of 0 to 90 with respect to a perpendicular through the feeding roller axis SA. This arrangement reduces any dead space around the feeding roller and facilitates residue emptying/cleaning of the distributing and metering device 1. A shroud 20 adjoins the edge 19 for sealing purposes. In the prior art, the feeding space encloses the feeding roller (discharge roller) for the most part, with the result that a dead zone is formed below the feeding roller (discharge roller) that cannot be completely emptied during operation and would thus have to be cleaned manually at a standstill. This dead zone can be an unwanted home for insects etc. Given the arrangement of the edge 19, it should therefore ideally be ensured that no such dead zone can form.

(11) During operation of the distributing and metering device 1, milling material is supplied through the milling-material inlet 3. Rotation of the conveying shaft 6 causes the milling material to be conveyed from the first end in the direction of the second end of the feeding roller 6. This distribution is monitored by the second filling level sensor 8. If the second milling-material filling level (actual value) measured by the second filling level sensor 8 deviates from a desired value of the second milling-material filling level, the rotational speed of the conveying shaft 6 is correspondingly adapted such that more or less milling material is conveyed to the other end of the feeding roller 5.

(12) The feeding roller 5 is driven at the same time. If the first milling-material filling level (actual value) measured by the first filling level sensor 7 deviates from a desired value of the first milling-material filling level, the rotational speed of the feeding roller 5 is correspondingly adapted such that more or less milling material is discharged to ensure that the filling height of the housing remains constant.

(13) In FIG. 3 there can be seen a roller mill 14 having a distributing and metering device 1. Emphasis should be placed on the switching cabinet 13 which is arranged on the roller mill and which accommodates the control unit 12 and is cooled by Peltier elements 17 (of which only cooling ribs are visible). Other ATEX-compliant cooling systems are also conceivable, for example liquid cooling systems, in particular water cooling systems; ATEX-compliant fans; etc.

(14) FIG. 4 diagrammatically illustrates a milling installation 22 or facility having a plurality of roller mills 14. As each of these roller mills 14 are described above with reference to the singular roller mill 14 and distributing and metering device 1 of FIGS. 1-3, no further description of the same is believed to be necessary.