Forage harvester with a magnetic assebmly

Patent metadata

Field	Value
Publication number	US-11109537-B2
Application number	US-201816217537-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Dec 13, 2017
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A forage harvester comprising an edge sharpness detection device for detecting a degree of edge sharpness of a cutting mechanism. The cutting mechanism comminutes a stream of harvested material, with a material inflow area being defined where the cutting blades interact with the shear bar to comminute the harvested material. The edge sharpness detection device excites one or more magnetic circuits, with the respective magnetic circuit being closed by the respective cutting blade during rotation of the cutter drum once one of the cutting blades passes the magnetic assembly. The edge sharpness detection device detects the magnetic flux in the respective magnetic circuit and, based on a detected change, determines a degree of edge sharpness of the respective cutting blade. Further, the magnetic flux of the magnetic circuit may be guided lengthwise in the cutting blade at least along a longitudinal section of the respective cutting blade.

First claim

The invention claimed is:

1. A forage harvester comprising:
a cutting mechanism configured to comminute a harvested material stream, the cutting mechanism including a cutter drum with a plurality of cutting blades and at least one shear bar configured to interact with the plurality of cutting blades in order to comminute the harvested material stream, wherein the cutting mechanism is supplied the harvested material stream by a prepressing unit, wherein a location at which the plurality of cutting blades interact with the at least one shear bar to comminute the harvested material stream comprises a material inflow area; and
an edge sharpness detection device configured to detect at least one aspect of edge sharpness of the cutting mechanism and comprising at least one magnetic circuit and a magnetic assembly;
wherein the edge sharpness detection device is configured to excite the at least one magnetic circuit using the magnetic assembly, wherein the at least one magnetic circuit is closed by a respective cutting blade during a rotation of the cutter drum once the respective cutting blade passes the magnetic assembly;
wherein at least part of a magnetic flux of the at least one magnetic circuit closed by the respective cutting blade is guided lengthwise at least along a longitudinal section of the respective cutting blade;
wherein the edge sharpness detection device is configured to detect the magnetic flux in the at least one magnetic circuit and, based on a detected change of a magnetic measurement relating to the magnetic flux, determine the at least one aspect of edge sharpness of the respective cutting blade; and
wherein the magnetic assembly is positioned at least partly outside of the material inflow area of the cutting mechanism.

2. The forage harvester of claim 1 , wherein the magnetic assembly is entirely outside of the material inflow area of the cutting mechanism.

3. The forage harvester of claim 1 , wherein the magnetic assembly is positioned at a location at which the harvested material stream passes by after its comminution by the plurality of cutting blades and the at least one shear bar.

4. The forage harvester of claim 1 , wherein the cutting mechanism includes a housing drum in which the cutter drum rotates; and
wherein the harvested material stream is guided away from the at least one shear bar after its comminution by the interaction of the plurality of cutting blades and the at least one shear bar between the cutter drum and the housing drum.

5. The forage harvester of claim 4 , wherein the magnetic assembly is positioned outside of an area between the cutter drum and the housing drum through which the harvested material stream is guided after its comminution.

6. The forage harvester of claim 5 , wherein the magnetic assembly is positioned outside of the housing drum, which surrounds the cutter drum.

7. The forage harvester of claim 4 , wherein the magnetic assembly is positioned within an area between the cutter drum and the housing drum through which the harvested material stream is guided after its comminution.

8. The forage harvester of claim 1 , wherein the magnetic assembly is positioned relative to the material inflow area such that the magnetic assembly does not come into contact with the harvested material stream before its comminution effectuated by the interaction of the plurality of cutting blades and the at least one shear bar or after its comminution effectuated by the interaction of the plurality of cutting blades and the at least one shear bar.

9. The forage harvester of claim 1 , wherein the magnetic assembly is positioned relative to the material inflow area such that the magnetic assembly does not come into contact with the harvested material stream before its comminution effectuated by the interaction of the plurality of cutting blades and the at least one shear bar and after its comminution effectuated by the interaction of the plurality of cutting blades and the at least one shear bar.

10. The forage harvester of claim 1 , wherein, in a direction of rotation of the cutter drum, the magnetic assembly is positioned behind the at least one shear bar or vertically below the at least one shear bar.

11. The forage harvester of claim 1 , wherein, in a direction of rotation of the cutter drum, the magnetic assembly is positioned behind the at least one shear bar and vertically below the at least one shear bar.

12. The forage harvester of claim 1 , wherein the cutting mechanism includes a housing drum in which the cutter drum rotates;
wherein the housing drum comprises a drum floor, a drum top and a drum rear wall; and
wherein after its comminution, the harvested material stream is guided out of the housing drum into a discharge channel through an opening between the drum floor and the drum top.

13. The forage harvester of claim 12 , wherein the magnetic assembly is positioned on at least one of the drum floor, the drum top, or the drum rear wall of the housing drum.

14. The forage harvester of claim 13 , wherein at least a part of the housing drum is composed of non-magnetic material.

15. The forage harvester of claim 13 , wherein the drum floor, the drum top, and the drum rear wall are composed of non-magnetic material.

16. The forage harvester of claim 1 , wherein the magnetic assembly comprises a pole assembly positioned stationary relative to the cutter drum that forms a first magnetic pole, a second magnetic pole and a third magnetic pole, each of the first magnetic pole, the second magnetic pole and the third magnetic pole comprising a respective pole surface to discharge the magnetic flux;
wherein the edge sharpness detection device comprises an exciter assembly configured to generate at least a first magnetic circuit and a second magnetic circuit, the first magnetic circuit flowing through the first magnetic pole and the second magnetic pole, the second magnetic circuit flowing through the second magnetic pole and the third magnetic pole;
wherein each of the first magnetic circuit and the second magnetic circuit are closed by the respective cutting blade during the rotation of the cutter drum;
wherein at least a part of the magnetic flux of the first magnetic circuit is guided lengthwise along a first section of the respective cutting blade;
wherein at least a part of the magnetic flux of the second magnetic circuit is guided lengthwise along a second section of the respective cutting blade; and
wherein the first section of the respective cutting blade and the second section of the respective cutting blade are not co-extensive.

17. The forage harvester of claim 16 , wherein the edge sharpness detection device includes only a single magnetic assembly in order to generate a magnetic field in the first magnetic circuit and the second magnetic circuit sufficient to perform edge sharpness detection along the first section of the respective cutting blade and the second section of the respective cutting blade.

18. The forage harvester of claim 16 , wherein the first section of the respective cutting blade and the second section of the respective cutting blade abut one another.

19. The forage harvester of claim 16 , wherein the edge sharpness detection device is configured to detect the at least one aspect of edge sharpness by:
determining a change in the magnetic flux of the first magnetic circuit as a representation of a degree of edge sharpness of the first section of the respective cutting blade; and
determining a change in the magnetic flux of the second magnetic circuit as a representation

Assignees

• Claas Selbstfahrende Erntemaschinen Gmbh

Inventors

• Neitemeier Dennis
• Heitmann Christoph
• Huster Jochen
• Brune Markus
• Kettelhoit Boris

Classifications

• A01D43/085

  Control or measuring arrangements specially adapted therefor · CPC title

• A01F29/095

  Mounting or adjusting of knives · CPC title

• G01B7/293

  for measuring radius of curvature · CPC title

• A01F29/22 Primary

  Arrangement of knife sharpening devices · CPC title

• A01F29/06

  having rotating knives with their cutting edges on a cylinder surface, e.g. of the helical-type · CPC title