GRINDING BODY HAVING REDUCED WEIGHT

Abstract

A grinding body including a substantially cylindrical outer member for receiving an abrasive material, an inner member for attaching the grinding body to a drive unit, and a connecting structure for mechanical force transmission between the outer member and the inner member. The outer member, the inner member, and/or the connecting structure may be made at least in part of a fiber-plastic composite.

Claims

1.-23. (canceled)

24. A grinding body comprising: a cylindrical outer member for receiving an abrasive material; an inner member configured to be attached to a drive unit; and a connecting structure for mechanical force transmission between the cylindrical outer member and the inner member, wherein at least one of the outer cylindrical member, the inner member, or the connecting structure comprises a fiber-plastic composite.

25. The grinding body of claim 24 wherein the inner member is cylindrical.

26. The grinding body of claim 24 wherein fibers of the fiber-plastic composite are formed as at least one of a laid web, a woven fabric, braiding, a surface structure, or a winding structure.

27. The grinding body of claim 24 wherein fibers of the fiber-plastic composite of at least one of the cylindrical outer member or the inner member are oriented at least for a portion in a circumferential direction of the at least one of the cylindrical outer member or the inner member.

28. The grinding body of claim 24 wherein fibers of the fiber-plastic composite are oriented at least for a portion along a surface of the at least one of the outer cylindrical member, the inner member, or the connecting structure.

29. The grinding body of claim 24 wherein the fiber-plastic composite is comprised of one or more layers.

30. The grinding body of claim 24 wherein the connecting structure is configured as a flat connecting element.

31. The grinding body of claim 24 wherein the connecting structure has a quasi-isotropic layer structure.

32. The grinding body of claim 24 wherein the connecting structure comprises a plurality of elements disposed in a spokelike arrangement.

33. The grinding body of claim 32 wherein the plurality of elements of the spokelike arrangement each comprise a core of foam material.

34. The grinding body of claim 24 wherein at least one of the cylindrical outer member, the inner member, or the connecting structure is comprised of a preform.

35. The grinding body of claim 24 wherein the connecting structure is attached by at least one of integral bonding or a form fit to the cylindrical outer member or the inner member.

36. The grinding body of claim 24 wherein fibers of the fiber-plastic composite comprise at least one of carbon fibers, glass fibers, basalt fibers, or aramide fibers.

37. The grinding body of claim 24 wherein matrix material of the fiber-plastic composite comprises a thermoset or a thermoplastic.

38. The grinding body of claim 24 comprising a metal bushing disposed at least partially inside the inner member.

39. The grinding body of claim 24 wherein the cylindrical outer member has a larger axial extension than the inner member.

40. The grinding body of claim 24 wherein the abrasive material is applied to the cylindrical outer member.

41. A method for making a grinding body comprising: forming a cylindrical outer member to receive an abrasive material; forming an inner member for attaching the grinding body to a drive unit; and forming a connecting structure for the mechanical force transmission between the cylindrical outer member and the inner member, wherein at least one of the cylindrical outer member, the inner member, or the connecting structure is comprised at least in part of a fiber-plastic composite.

42. The method of claim 41 comprising forming at least one of the cylindrical outer member, the inner member, or the connecting structure by placing fibers on a mold and then infiltrating the fibers with plastic.

43. The method of claim 42 comprising stripping the grinding body by removing the at least one of the cylindrical outer member, the inner member, or the connecting structure from the mold after the infiltration with plastic.

44. The method of claim 42 wherein the mold comprises separate mold sections for the cylindrical outer member, the inner member, and the connecting structure.

45. The method of claim 41 comprising positioning and securing a metal bushing at least partially inside the inner member.

Description

[0042] The drawing shows in

[0043] FIGS. 1a, b a first exemplary embodiment of a grinding body according to the first aspect in a partial top view and in a partial longitudinal section;

[0044] FIGS. 2a, b a second exemplary embodiment of a grinding body according to the first aspect in a partial top view and in a partial longitudinal section;

[0045] FIG. 3 a schematic representation of an advantageous fiber orientation; and

[0046] FIG. 4a-d a schematic representation of an exemplary embodiment of a method of production according to the third aspect.

[0047] FIG. 1 shows first of all a first exemplary embodiment of a grinding body 1 according to the first aspect in partial top view (FIG. 1a) and in partial longitudinal section (FIG. 1b).

[0048] The grinding body 1 comprises a substantially cylindrical outer member 2 for receiving an abrasive material (not shown). The abrasive material may be applied, for example, flat against the outside of the outer member 2. Furthermore, the grinding body 1 has a substantially cylindrical inner member 4 for attaching the grinding body 1 to a drive unit (not shown) and a connecting structure 6 for the mechanical force transmission between the outer member 2 and the inner member 4. The outer member 2, the inner member 4 and the connecting structure 6 are all formed from a fiber-plastic composite, the fibers each being organic reinforcing fibers, in this case carbon fibers. Alternatively or additionally, however, other fibers may also be used, such as glass fibers, basalt fibers, or aramide fibers. The plastic or the matrix material of the fiber-plastic composite can be a thermoset or a thermoplastic.

[0049] The connecting structure 6 here is formed of several radially outwardly running spokelike arranged struts, of which only two struts 6a, 6b are represented here. This has the advantage that, due to the cutout areas, a depositing of grinding dust on the connecting structure 6 can be reduced. The struts 6a, 6b etc. may have a core of foam material, in order to make possible an especially lightweight variant of the grinding body 1.

[0050] The connecting structure 6 here is attached in particular by integral bonding to both the outer member 2 and to the inner member 4. This can be accomplished, in particular, by means of a plastic infiltration.

[0051] The outer member 2 and the inner member 4 are concentrically arranged and have a common cylinder axis 8. The outer member 2 and the inner member 4 extend respectively in both directions, starting from the connecting structure 6, substantially parallel to the axis 8. As can be seen, the outer member 2 has a greater axial extension than the inner member 4 on one side, or the inner member 4 has a correspondingly shorter axial extension on one side. Thanks to this asymmetrical configuration, a further weight reduction is accomplished in particular, which makes possible a reduction of the rotational mass and the centrifugal forces during the machining process and thus a higher acceleration.

[0052] The fibers of the fiber-plastic composite of the outer member 2, the inner member 4 and the connecting structure 6 are preferably formed as a laid web, woven fabric, braiding, surface structure and/or winding structure. Preferably the fiber-plastic composite of the outer member 2, the inner member 4 and the connecting structure 6 has a multilayer construction. The fibers of the outer member 2, the inner member 4 and the connecting structure 6 are made of preforms.

[0053] Inside the inner member 4 there is furthermore arranged a metal bushing 10 as a hub element, by which a shaft and hub connection can be produced. The inner member 4 has been shrunk-fit onto the metal bushing 10, so that the metal bushing 10 is fixed by means of a press fit in the inner member 4. The inner member 4 and/or the metal bushing 10 are/is formed conically tapering, looking along the cylinder axis 8.

[0054] FIG. 2 now shows a second exemplary embodiment of a grinding body 1 according to the first aspect in top view (2a) and in longitudinal section (2b). The second exemplary embodiment is similar to the exemplary embodiment represented in FIG. 1. Accordingly, reference is at first made to the remarks on FIG. 1 and the same reference numbers (with an added stroke) shall be used. The differences shall be discussed below.

[0055] In the exemplary embodiment represented in FIG. 2 the connecting structure 6 of the grinding body 1 in particular has a different configuration. The connecting structure 6 in this case is formed as a flat, disc-shaped connecting element 6. The disc-shaped connecting structure 6 in this case has a quasi-isotropic layer structure, so that the connecting structure 6 behaves in the plane in a similar manner to a metallic material.

[0056] The grinding body 1 furthermore has a cover 12. The cover 12 is provided at one end of the grinding body 1, so that the space between the outer member 2 and the inner member 4 is covered. In this way, an excessive accumulation of grinding dust between the outer member 2, the inner member 1 and the disc-shaped connecting structure 6 can be prevented.

[0057] FIG. 3 shows a schematic representation of one advantageous fiber orientation of a grinding body. The grinding body may be, for example, the grinding body 1 of FIG. 1 or the grinding body 1 of FIG. 2.

[0058] As indicated by the broken lines, the fibers of the fiber-plastic composite of the outer member 2, 2 and the inner member 4, 4 are oriented at least for a portion in the circumferential direction of the respective member. The fibers of the fiber-plastic composite of the outer member 2, 2, the inner member 4, 4 and the connecting structure 6, 6 are oriented at least partly along the respective surface.

[0059] FIG. 4a-d now show a schematic representation of an exemplary embodiment of a method of production according to the third aspect. In this case, the grinding body 1 shown in FIG. 2 is being produced. However, the production method shown may also be applied to the production of a different grinding body, such as the grinding body 1.

[0060] First of all, fibers 30 are applied as a disc-shaped preform on a mold section 20 in order to form the later connecting structure 6, 6 (FIG. 4a).

[0061] After this, fibers 32 are applied as a preform on a cylindrical mold section 22 in order to form the later inner member 4, 4 (FIG. 4b). The mold sections 20 and 22 may then be joined together.

[0062] Now, the mold sections 20, 22 are connected to a further cylindrical mold section 24. On the mold section, consisting of the mounted molds 20 and 24, the fibers 34 are applied by a braiding process to form the later outer member 2, 2 (FIG. 4c).

[0063] After this, an enclosing outer mold (not shown) is mounted in place, modeling the negative-shaped substantially cylindrical contour of the outer member 2, 2 being formed. The outer mold and the now inside molds 20, 22, 24 form the mold cavity for the fibers 30, 32, 34. The cylindrical contour may also have changes in diameter in order thus to be able to apply offset or stepped abrasive coatings, without having to machine by cutting (milling/turning) the offset outer contour of the consolidated fiber composite body.

[0064] Finally, the fibers 30, 32, 34 are infiltrated with plastic, so that the outer member 2, 2, the inner member 4, 4 and the connecting structure 6, 6 are formed from a fiber-plastic composite. After the infiltration and consolidation, the grinding body 1 can be stripped by removing the individual mold sections 20, 22, 24 (FIG. 4d).