Method for Electrostatically Scattering an Abrasive Grain

20190366511 ยท 2019-12-05

    Inventors

    Cpc classification

    International classification

    Abstract

    A method for electrostatically scattering an abrasive grain includes applying at least one electro-conductive material to the abrasive grain. The electro-conductive material is in the form of at least one organic compound.

    Claims

    1. A method for electrostatic scattering of an abrasive grain comprising: applying at least one electrically conductive material to the abrasive grain, wherein the at least one electrically conductive material is at least one organic compound.

    2. The method as claimed in claim 1, wherein the applying the at least one electrically conductive material comprises: applying at least one ionic liquid to the abrasive grain.

    3. The method as claimed in claim 1, wherein the applying the at least one electrically conductive material comprises: applying an intrinsically conductive polymer to the abrasive grain.

    4. The method as claimed in claim 1, wherein a mass proportion of the at least one organic compound applied to the abrasive grain is less than 5% of a total mass of the abrasive grain covered with the at least one organic compound.

    5. The method as claimed in claim 1, wherein a maximum layer thickness of the at least one organic compound applied to the abrasive grain is less than thirty microns.

    6. An abrasive grain that is electrostatically scatterable, comprising: at least one coating including at least one electrically conductive organic compound applied to the abrasive grain.

    7. The abrasive grain as claimed in claim 6, wherein the at least one coating is at least one ionic liquid and/or at least one conductive polymer.

    8. The abrasive grain as claimed in claim 6, further comprising: an abrasive material containing diamond, ceramics, corundum, silicon carbide, tungsten carbide, zirconium oxide, and/or ceroxide.

    9. The abrasive grain as claimed in claim 6, wherein an abrasive grain diameter of the abrasive grain is more than ten microns.

    10. The abrasive grain as claimed in claim 6, wherein the at least one coating is of an at least partially hydrophobic form.

    11. (canceled)

    Description

    DRAWING

    [0021] Further advantages result from the following description of the drawing. An exemplary embodiment of the invention is shown in the drawing. The drawing, description and claims contain numerous features in combination. The person skilled in the art will consider the features appropriately and individually and will combine them into meaningful further combinations.

    [0022] In the figures:

    [0023] FIG. 1 shows an overview sketch of the method according to the invention for the electrostatic scattering of an abrasive grain,

    [0024] FIG. 2 shows a flowchart of the method,

    [0025] FIG. 3 shows a coated abrasive grain in a sectional view,

    [0026] FIGS. 4 (a) and (b) show an enlarged view of an abrasive means produced by means of the method, and

    [0027] FIG. 5 shows the grinding means in the form of a grinding wheel.

    DESCRIPTION OF THE EXEMPLARY EMBODIMENT

    [0028] FIG. 1 shows a schematic process of the method for the electrostatic scattering of an abrasive grain 10. In at least one process step 30, an electrically conductive material 14 is provided. The electrically conductive material 14 is in the form of an organic compound. The electrically conductive material 14 may in particular at least partly contain other liquids and/or may be diluted with water.

    [0029] In at least one process step 12, 16, 18, the electrically conductive material 14 is applied to the abrasive grain 10.

    [0030] In at least one process step 16, the electrically conductive material 14 is in the form of an ionic liquid. In at least one process step 16, the ionic liquid in the form of an organic compound is applied to the abrasive grain 10.

    [0031] In at least one process step 18, the electrically conductive material 14 is in the form of an intrinsically conductive polymer. In at least one process step 18, the intrinsically conductive polymer in the form of an organic compound is applied to the abrasive grain 10.

    [0032] A mass proportion of the organic compound applied to the abrasive grain 10 in at least one process step 12, 16, 18 is less than 5% of the total mass of the abrasive grain 10 covered by the organic compound. The mass proportion of the electrically conductive material 14 applied to the abrasive grain 10 in at least one process step 12, 16, 18 is less than 5% of the total mass of the abrasive grain 10 covered by the electrically conductive material 14. The mass proportion of the ionic liquid applied to the abrasive grain 10 in at least one process step 16 is less than 5% of the total mass of the abrasive grain 10 covered by the ionic liquid. The mass proportion of the intrinsically conductive polymer that is applied to the abrasive grain 10 in at least one process step 18 is less than 5% of the total mass of the abrasive grain 10 covered by the intrinsically conductive polymer.

    [0033] A maximum layer thickness 20 (cf. FIG. 3) of the electrically conductive material 14 that is applied to the abrasive grain 10 in at least one process step 12, 16, 18 is less than 30 microns.

    [0034] In at least one process step 26, the coated abrasive grain 10 is dried. During drying, water and/or solvents from the electrically conductive material 14 and/or a coating 22 of the abrasive grain 10 evaporate (see FIG. 3).

    [0035] In at least one process step 28, coated abrasive grain 10 is electrostatically scattered. In electrostatic scattering, the abrasive grain 10 is accelerated in an electric field 42. The abrasive grain 10 moves in the electric field 42 towards a base 36. The base 36 comprises a binding agent 40. The binding agent 40 is provided to produce an adhesive force between the base 36 and the abrasive grain 10. Under the influence of the binding agent 40, the abrasive grain 10 adheres to the base 36. The electric field 42 also serves to align the abrasive grain 10 on the base 36, in particular before generating the adhesive force. In addition, a further alignment can take place in the electric field 42, in particular along electric field lines after and/or during an adhesive process and/or during the build-up of the adhesive force, in particular after the abrasive grain 10 has arrived on the base 36. Thus, uniform alignment of the abrasive grains 10 can be advantageously achieved, wherein for example, the abrasive grain 10 can have at least one pointed edge 44, which points away from the base 36, in particular due to the alignment in the electric field 42.

    [0036] FIG. 2 shows a schematic flow diagram of the method for electrostatic scattering of the abrasive grain 10. In at least one process step 46, the abrasive grain 10 is aligned relative to the base 36 by means of the electric field 42. In particular, it is conceivable that a person skilled in the art may also make use of an alternative sequence of process steps 12, 16, 18, 26, 28, 30, 32, 34, 46, 48, 50 that seems sensible to him.

    [0037] In at least one process step 32, a frictional connection between the base 36 and the abrasive grain 10 is made by means of the binding agent 40.

    [0038] In at least one process step 34 the electrically conductive material 14 diffuses in particular to a large extent, preferably completely. Preferably, the electrically conductive material 14 diffuses into the binding agent 40. This can advantageously produce a hard surface for grinding, in particular formed by the abrasive grain 10.

    [0039] Alternatively, in at least one process step 48 the electrically conductive material 14 is flushed out. Preferably, the electrically conductive material 14 is in a water-soluble form.

    [0040] In at least one process step 50, an abrasive means 24, for example a grinding wheel 52 (cf. FIG. 5), is made from the base 36 to which a plurality of abrasive grains 10 adhere.

    [0041] FIG. 3 shows a section through an abrasive grain 10. The abrasive grain 10 has the coating 22. The coating 22 comprises an electrically conductive material 14 and/or an electrically conductive organic compound and/or an ionic liquid and/or an intrinsically conductive polymer. The coating 22 has a layer thickness 20. The layer thickness 20 is less than 30 microns. The abrasive grain 10 has a pointed edge 44. The coating 22 is of at least partially hydrophobic form.

    [0042] The abrasive material of the abrasive grain 10 contains diamond, ceramic, corundum, silicon carbide, tungsten carbide, zirconium oxide and/or ceroxide.

    [0043] The abrasive grain 10 has an abrasive grain size, in particular an abrasive grain diameter, of more than 10 microns.

    [0044] FIG. 4a and FIG. 4b each show an enlarged view of the abrasive means 24. The abrasive means 24 each comprise a base 36 and a plurality of abrasive grains 10. The abrasive grains 10 of the abrasive means 24 shown in FIG. 4a have an irregular form 58.

    [0045] The abrasive grains 10 of the abrasive means 24 shown in FIG. 4a are arranged in an unaligned way. The abrasive grains 10 of the abrasive means 24 shown in FIG. 4b essentially have a three-sided prism shape 60.

    [0046] The abrasive grains 10 of the abrasive means 24 shown in FIG. 4b are arranged in an aligned way. The pointed edge of the three-sided prism shape 60 is oriented in a direction essentially pointing away from the base 36.

    [0047] FIG. 5 shows a full view of the abrasive means 24 with the plurality of abrasive grains 10. The abrasive means is in the form of a grinding wheel 52. The grinding wheel 52 has an at least substantially round, flat disc shape 38. A hub 54 is disposed in the center of the grinding wheel 52. The hub 54 is in the form of a hole in the grinding wheel 52. The hub 54 is used to attach the grinding wheel 52 to a tool. In a grinding operation, the grinding wheel 52 is provided to rotate about a rotary axis 56 that is disposed in particular in the center of the hub 54, perpendicular to the base 36.